Fate and potential environmental effects of methylenediphenyl diisocyanate and toluene diisocyanate released into the atmosphere.

PubMed

Tury, Bernard; Pemberton, Denis; Bailey, Robert E

2003-01-01

Information from a variety of sources has been collected and summarized to facilitate an overview of the atmospheric fate and potential environmental effects of emissions of methylenediphenyl diisocyanate (MDI) or toluene diisocyanate (TDI) to the atmosphere. Atmospheric emissions of both MDI and TDI are low, both in terms of concentration and mass, because of their low volatility and the need for careful control over all aspects of their lifecycle from manufacture through disposal. Typical emission losses for TDI are 25 g/t of TDI used in slabstock foam production. MDI emission losses are lower, often less than 1 g/t of MDI used. Dispersion modeling predicts that concentrations at the fenceline or beyond are very low for typical releases. Laboratory studies show that TDI (and by analogy MDI) does not react with water in the gas phase at a significant rate. The primary degradation reaction of these aromatic diisocyanates in the atmosphere is expected to be oxidation by OH radicals with an estimated half-life of one day. Laboratory studies also show that this reaction is not expected to result in increased ground-level ozone accumulation.

Assessing the concentrations and risks of toxicity from the antibiotics ciprofloxacin, sulfamethoxazole, trimethoprim and erythromycin in European rivers.

PubMed

Johnson, Andrew C; Keller, Virginie; Dumont, Egon; Sumpter, John P

2015-04-01

This study evaluated the potential concentrations of four antibiotics: ciprofloxacin (CIP), sulfamethoxazole (SUF), trimethoprim (TRI) and erythromycin (ERY) throughout the rivers of Europe. This involved reviewing national consumption rates together with assessing excretion and sewage treatment removal rates. From this information, it was possible to construct best, expected and worst case scenarios for the discharge of these antibiotics into rivers. Consumption data showed surprising variations, up to 200-fold in the popularity of different antibiotics across different European nations. Using the water resources model GWAVA which has a spatial resolution of approximately 6×9 km, river water concentrations throughout Europe were predicted based on 31-year climate data. The modelled antibiotic concentrations were within the range of measurements reported previously in European effluents and rivers. With the expected scenario, the predicted annual-average antibiotic concentrations ranged between 0 and 10 ng/L for 90% by length of surface waters. In the worst case scenario concentrations could reach between 0.1 and 1 μg/L at the most exposed locations. As both predicted and observed sewage effluent concentrations were below reported effect levels for the most sensitive aquatic wildlife, no direct toxicity in rivers is expected. Predicted river concentrations for CIP and ERY were closest to effect levels in wildlife, followed by SUF which was 2-3 orders of magnitude lower. TRI appeared to be of the least concern with around 6 orders of magnitude difference between predicted and effect levels. However, mixture toxicity may elevate this risk and antibiotic levels of 0.1-1 μg/L in hotspots may contribute to local environmental antibiotic resistance in microorganisms. Copyright © 2014 Elsevier B.V. All rights reserved.

Quantification of four artificial sweeteners in Finnish surface waters with isotope-dilution mass spectrometry.

PubMed

Perkola, Noora; Sainio, Pirjo

2014-01-01

The artificial sweeteners sucralose (SCL), acesulfame (ACS), saccharin (SAC), and cyclamate (CYC) have been detected in environmental waters in Europe and North America. Higher environmental levels are expected in view of the increasing consumption of these food additives. In this study, an isotope-dilution mass spectrometry (IDMS) LC-MS/MS method was developed and validated for quantifying the four artificial sweeteners in boreal lakes (n = 3) and rivers (n = 12). The highest concentrations of ACS, SAC, CYC and SCL were 9,600, 490, 210 and 1000 ng/L, respectively. ACS and SAC were detected in all studied samples, and CYC and SCL in 98% and 56% of the samples. Seasonal trends of ACS and SAC were observed in some rivers. ACS and SCL concentrations in rivers correlated linearly with population equivalents of the wastewater treatment plants in the catchment areas, whereas SAC and CYC concentrations depend more on the source. Copyright © 2013 Elsevier Ltd. All rights reserved.

Combining monitoring data and modeling identifies PAHs as emerging contaminants in the arctic.

PubMed

Laender, F De; Hammer, J; Hendriks, A J; Soetaert, K; Janssen, C R

2011-10-15

Protecting Arctic ecosystems against potential adverse effects from anthropogenic activities is recognized as a top priority. In particular, understanding the accumulation and effects of persistent organic pollutants (POPs) in these otherwise pristine ecosystems remains a scientific challenge. Here, we combine more than 20,000 tissue concentrations, a food web bioaccumulation model, and time trend analyses to demonstrate that the concentrations of legacy-POPs in the Barents/Norwegian Sea fauna decreased 10-fold between 1985 and 2010, which reflects regulatory efforts to restrict these substances. In contrast, concentrations of fossil fuel derived PAHs in lower trophic levels (invertebrates and fish) increased 10 to 30 fold over the past 25 years and now dominate the summed POP burden (25 POPs, including 11 PAHs) in these biota. Before 2000, PCBs dominated the summed POP burden in top predators. Our findings indicate that the debate on the environmental impacts of fossil fuel burning should move beyond the expected seawater temperature increase and examine the possible environmental impact of fossil fuel derived PAHs.

Mapping chemicals in air using an environmental CAT scanning system: evaluation of algorithms

NASA Astrophysics Data System (ADS)

Samanta, A.; Todd, L. A.

A new technique is being developed which creates near real-time maps of chemical concentrations in air for environmental and occupational environmental applications. This technique, we call Environmental CAT Scanning, combines the real-time measuring technique of open-path Fourier transform infrared spectroscopy with the mapping capabilitites of computed tomography to produce two-dimensional concentration maps. With this system, a network of open-path measurements is obtained over an area; measurements are then processed using a tomographic algorithm to reconstruct the concentrations. This research focussed on the process of evaluating and selecting appropriate reconstruction algorithms, for use in the field, by using test concentration data from both computer simultation and laboratory chamber studies. Four algorithms were tested using three types of data: (1) experimental open-path data from studies that used a prototype opne-path Fourier transform/computed tomography system in an exposure chamber; (2) synthetic open-path data generated from maps created by kriging point samples taken in the chamber studies (in 1), and; (3) synthetic open-path data generated using a chemical dispersion model to create time seires maps. The iterative algorithms used to reconstruct the concentration data were: Algebraic Reconstruction Technique without Weights (ART1), Algebraic Reconstruction Technique with Weights (ARTW), Maximum Likelihood with Expectation Maximization (MLEM) and Multiplicative Algebraic Reconstruction Technique (MART). Maps were evaluated quantitatively and qualitatively. In general, MART and MLEM performed best, followed by ARTW and ART1. However, algorithm performance varied under different contaminant scenarios. This study showed the importance of using a variety of maps, particulary those generated using dispersion models. The time series maps provided a more rigorous test of the algorithms and allowed distinctions to be made among the algorithms. A comprehensive evaluation of algorithms, for the environmental application of tomography, requires the use of a battery of test concentration data before field implementation, which models reality and tests the limits of the algorithms.

Measurement systems and indices of miners' exposure to radon daughter products in the air of mines.

PubMed

Domański, T

1990-01-01

This paper presents the classification of measurement systems that may be used for the assessment of miners' exposure to radiation in mines. The following systems were described and characterized as the Air Sampling System (ASS), the Environmental Control System (ECS), the Individual Dosimetry System (IDS), the Stream Monitoring System (SMS) and the Exhaust Monitoring System (EMS). The indices for evaluation of miners' working environments, or for assessment of individual or collective miners' exposure, were selected and determined. These are: average expected concentration (CAE), average observed concentration (CAO), average expected rate of exposure cumulation rate (EEXP), average observed exposure cumulation rate (EOBS), average effective exposure cumulation rate (EEFF). Mathematical formulae for determining all these indicators, according to the type of measurement system used in particular mines, are presented. The reliability of assessment of miners' exposure in particular measurement systems, as well as the role of the possible reference system, are discussed.

Environmental factors during adolescence associated with later development of psychotic disorders - a nested case-control study.

PubMed

Bratlien, Unni; Øie, Merete; Haug, Elisabeth; Møller, Paul; Andreassen, Ole A; Lien, Lars; Melle, Ingrid

2014-03-30

Etiologies of psychotic disorders (schizophrenia and bipolar disorder) are conceptualized as interplay between genetic and environmental factors. The adolescent period is characterized by changes in social roles and expectations that may interact with biological changes or psychosocial stressors. Few studies focus on the adolescents' own reports of perceived risk factors. To assess differences at age 16 between persons who later develop psychotic disorders ("Confirmed Psychosis", CP) and their class-mates ("Population Controls", PC) we collected information on: (1) Social support factors (size of social network and expectancies of social support from friends), (2) Cognitive functioning (concentrating in the classroom, actual grades and expectancies of own academic achievements) and (3) Problems and stressors in families (illness or loss of work for parents), and in relationship with others (exposure to bullying, violence or sexual violation). Self-reported data from students at 15-16 years of age were linked to the case-registers from the "Thematically Organized Psychosis (TOP) Study". The CP group reported more economic problems in their families, smaller social network and lower academic expectation than the PC group. The results support the notion that long-term socioeconomic stressors in adolescence may serve as risk factors for the development of psychotic disorders. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Addressing the complexity of water chemistry in environmental fate modeling for engineered nanoparticles.

PubMed

Sani-Kast, Nicole; Scheringer, Martin; Slomberg, Danielle; Labille, Jérôme; Praetorius, Antonia; Ollivier, Patrick; Hungerbühler, Konrad

2015-12-01

Engineered nanoparticle (ENP) fate models developed to date - aimed at predicting ENP concentration in the aqueous environment - have limited applicability because they employ constant environmental conditions along the modeled system or a highly specific environmental representation; both approaches do not show the effects of spatial and/or temporal variability. To address this conceptual gap, we developed a novel modeling strategy that: 1) incorporates spatial variability in environmental conditions in an existing ENP fate model; and 2) analyzes the effect of a wide range of randomly sampled environmental conditions (representing variations in water chemistry). This approach was employed to investigate the transport of nano-TiO2 in the Lower Rhône River (France) under numerous sets of environmental conditions. The predicted spatial concentration profiles of nano-TiO2 were then grouped according to their similarity by using cluster analysis. The analysis resulted in a small number of clusters representing groups of spatial concentration profiles. All clusters show nano-TiO2 accumulation in the sediment layer, supporting results from previous studies. Analysis of the characteristic features of each cluster demonstrated a strong association between the water conditions in regions close to the ENP emission source and the cluster membership of the corresponding spatial concentration profiles. In particular, water compositions favoring heteroaggregation between the ENPs and suspended particulate matter resulted in clusters of low variability. These conditions are, therefore, reliable predictors of the eventual fate of the modeled ENPs. The conclusions from this study are also valid for ENP fate in other large river systems. Our results, therefore, shift the focus of future modeling and experimental research of ENP environmental fate to the water characteristic in regions near the expected ENP emission sources. Under conditions favoring heteroaggregation in these regions, the fate of the ENPs can be readily predicted. Copyright © 2014 Elsevier B.V. All rights reserved.

Dimensionless Analysis Applied to Bacterial Chemotaxis towards NAPL Contaminants

NASA Astrophysics Data System (ADS)

Wang, X.; GAO, B.; Zhong, W.; Kihaule, K. S.; Ford, R.

2017-12-01

The use of chemotactic bacteria in bioremediation may improve the efficiency and decrease the cost of restoration, which means it has the potential to address environmental problems caused by oil spills. However, most previous studies were focused at the laboratory-scale and there lacks a formalism that can use these laboratory-scale results as input to evaluate the relative importance of chemotaxis at the field scale. In this study, a dimensionless equation is formulated to solve this problem. First, the main influential factors were extracted based on previous researches in environmental bioremediation and then five sets of dimensionless numbers were obtained according to Buckingham theory. After collecting basic parameter values and supplementary calculations to determine the concentration gradient of the chemoattractant, all dimensionless numbers were calculated and categorized into two types, those that were sensitive to chemotaxis or those to groundwater velocity. The bacteria ratio (BR), defined as the ratio of maximum bacteria concentration to its original value, was correlated with a combination of dimensionless numbers to yield, BR=cP1-0.085P20.329P30.1P4-0.098. For a bacterial ratio greater than one, the bioremediation strategy based on chemotaxis is expected to be effective, and chemotactic bacteria are expected to accumulate around NAPL contaminant sources efficiently.

Low impact of exposure to environmentally relevant doses of 226Ra in Atlantic cod (Gadus morhua) embryonic cells.

PubMed

Olsvik, Pål A; Berntssen, Marc H G; Hylland, Ketil; Eriksen, Dag Ø; Holen, Elisabeth

2012-07-01

The aim of this study was to investigate whether (226)Ra, a radionuclide present in produced water from oil platforms in the North Sea and other offshore drilling areas, could affect vulnerable early life stages of Atlantic cod (Gadus morhua). Blastula-stage embryonic cells (EC) from fertilized eggs of Atlantic cod were isolated and exposed to environmental relevant concentrations of (226)Ra and transcription of selected genes quantified. The results showed a weak, but significant up-regulation of GPx3 and HSP70 transcripts after 48 h of exposure to 2.11 Bq/L. In EC exposed to three (226)Ra concentrations (2.11, 23 and 117 Bq/L) for 12 h, metallothionein, HSP90AA, thioredoxin and caspase 8 were significantly up-regulated in cells exposed to 117 Bq/L, whereas thioredoxin was also significantly up-regulated in EC exposed to 23 Bq/L. When EC were exposed to the same (226)Ra concentrations for 48 h, only heme oxygenase was significantly up-regulated in the 23 Bq/L exposure group. The results suggest that environmentally relevant activities of (226)Ra may induce oxidative stress and apoptosis in fish ECs. Exposure of Atlantic cod EC to Cd, selected as a model toxicant, supported the ability of EC around blastula stage to respond to toxicants by altered transcription. Due to dilution, environmentally relevant concentrations of radionuclides present in produced water would be expected to pose a minor threat to early life stages of fish. Copyright © 2012 Elsevier Ltd. All rights reserved.

Application of mixed based membrane technology from component materials bintaro, zeolite and bentonite to reduction of songket waste liquid cloth

NASA Astrophysics Data System (ADS)

Dahlan, Muhammad Hatta; Saleh, Abdullah; Asip, Faisol; Makmun, Akbar; Defi

2017-11-01

Application of membrane technology based on clay mixture, Activated Carbon from Bintaro, Zeolite and Bentonit to process the waste water of Songket cloth is Palembang traditionally cloth. The applied research is into the superior field of industrial and household waste processing with membrane ceramic technology. The objective of this research is to design the liquid waste separation tool of jumputan cloth using better and simpler ceramic membrane so that it can help the artisans of Palembang songket or songket in processing the waste in accordance with the standard of environmental quality standard (BML) and Pergub Sumsel no. 16 in 2005. The specific target to be achieved can decrease the waste of cloth jumputan in accordance with applicable environmental quality standards the method used in achieving the objectives of this study using 2 processes namely the adsorption process using activated carbon and the separation process using a ceramic membrane based on the composition of the mixture. The activated carbon from bintaro seeds is expected to decrease the concentration of liquid waste of Songket cloth. Bintaro seeds are non-edible fruits where the composition contains organic ingredients that can absorb because contains dyes and filler metals. The process of membranization in the processing is expected to decrease the concentration of waste better and clear water that can be used as recycled water for household use. With the composition of a mixture of clay-based materials: zeolite, bentonit, activated carbon from bintaro seeds are expected Find the solution and get the novelty value in the form of patent in this research

Whole-cell bioreporters and risk assessment of environmental pollution: A proof-of-concept study using lead.

PubMed

Zhang, Xiaokai; Qin, Boqiang; Deng, Jianming; Wells, Mona

2017-10-01

As the world burden of environmental contamination increases, it is of the utmost importance to develop streamlined approaches to environmental risk assessment in order to prioritize mitigation measures. Whole-cell biosensors or bioreporters and speciation modeling have both become of increasing interest to determine the bioavailability of pollutants, as bioavailability is increasingly in use as an indicator of risk. Herein, we examine whether bioreporter results are able to reflect expectations based on chemical reactivity and speciation modeling, with the hope to extend the research into a wider framework of risk assessment. We study a specific test case concerning the bioavailability of lead (Pb) in aqueous environments containing Pb-complexing ligands. Ligands studied include ethylene diamine tetra-acetic acid (EDTA), meso-2,3 dimercaptosuccinic acid (DMSA), leucine, methionine, cysteine, glutathione, and humic acid (HA), and we also performed experiments using natural water samples from Lake Tai (Taihu), the third largest lake in China. We find that EDTA, DMSA, cysteine, glutathione, and HA amendment significantly reduced Pb bioavailability with increasing ligand concentration according to a log-sigmoid trend. Increasing dissolved organic carbon in Taihu water also had the same effect, whereas leucine and methionine had no notable effect on bioavailability at the concentrations tested. We find that bioreporter results are in accord with the reduction of aqueous Pb 2+ that we expect from the relative complexation affinities of the different ligands tested. For EDTA and HA, for which reasonably accurate ionization and complexation constants are known, speciation modeling is in agreement with bioreporter response to within the level of uncertainty recognised as reasonable by the United States Environmental Protection Agency for speciation-based risk assessment applications. These findings represent a first step toward using bioreporter technology to streamline the biological confirmation or validation of speciation modeling for use in environmental risk assessment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental whole-lake increase of dissolved organic carbon concentration produces unexpected increase in crustacean zooplankton density

USGS Publications Warehouse

Kelly, Patrick T.; Craig, Nicola; Solomon, Christopher T.; Weidel, Brian C.; Zwart, Jacob A.; Jones, Stuart E.

2016-01-01

The observed pattern of lake browning, or increased terrestrial dissolved organic carbon (DOC) concentration, across the northern hemisphere has amplified the importance of understanding how consumer productivity varies with DOC concentration. Results from comparative studies suggest these increased DOC concentrations may reduce crustacean zooplankton productivity due to reductions in resource quality and volume of suitable habitat. Although these spatial comparisons provide an expectation for the response of zooplankton productivity as DOC concentration increases, we still have an incomplete understanding of how zooplankton respond to temporal increases in DOC concentration within a single system. As such, we used a whole-lake manipulation, in which DOC concentration was increased from 8 to 11 mg L−1 in one basin of a manipulated lake, to test the hypothesis that crustacean zooplankton production should subsequently decrease. In contrast to the spatially derived expectation of sharp DOC-mediated decline, we observed a small increase in zooplankton densities in response to our experimental increase in DOC concentration of the treatment basin. This was due to significant increases in gross primary production and resource quality (lower seston carbon-to-phosphorus ratio; C:P). These results demonstrate that temporal changes in lake characteristics due to increased DOC may impact zooplankton in ways that differ from those observed in spatial surveys. We also identified significant interannual variability across our study region, which highlights potential difficulty in detecting temporal responses of organism abundances to gradual environmental change (e.g., browning).

Improving tritium exposure reconstructions using accelerator mass spectrometry

PubMed Central

Hunt, J. R.; Vogel, J. S.; Knezovich, J. P.

2010-01-01

Direct measurement of tritium atoms by accelerator mass spectrometry (AMS) enables rapid low-activity tritium measurements from milligram-sized samples and permits greater ease of sample collection, faster throughput, and increased spatial and/or temporal resolution. Because existing methodologies for quantifying tritium have some significant limitations, the development of tritium AMS has allowed improvements in reconstructing tritium exposure concentrations from environmental measurements and provides an important additional tool in assessing the temporal and spatial distribution of chronic exposure. Tritium exposure reconstructions using AMS were previously demonstrated for a tree growing on known levels of tritiated water and for trees exposed to atmospheric releases of tritiated water vapor. In these analyses, tritium levels were measured from milligram-sized samples with sample preparation times of a few days. Hundreds of samples were analyzed within a few months of sample collection and resulted in the reconstruction of spatial and temporal exposure from tritium releases. Although the current quantification limit of tritium AMS is not adequate to determine natural environmental variations in tritium concentrations, it is expected to be sufficient for studies assessing possible health effects from chronic environmental tritium exposure. PMID:14735274

Is it the time to study air pollution effects under environmental conditions? A case study to support the shift of in vitro toxicology from the bench to the field.

PubMed

Gualtieri, Maurizio; Grollino, Maria Giuseppa; Consales, Claudia; Costabile, Francesca; Manigrasso, Maurizio; Avino, Pasquale; Aufderheide, Michaela; Cordelli, Eugenia; Di Liberto, Luca; Petralia, Ettore; Raschellà, Giuseppe; Stracquadanio, Milena; Wiedensohler, Alfred; Pacchierotti, Francesca; Zanini, Gabriele

2018-09-01

Air pollution and particulate matter are recognised cause of increased disease incidence in exposed population. The toxicological processes underlying air pollution associated effects have been investigated by in vivo and/or in vitro experimentation. The latter is usually performed by exposing cells cultured under submerged condition to particulate matter concentration quite far from environmental exposure expected in humans. Here we report for the first time the feasibility of a direct exposure of air liquid interface cultured cells to environmental concentration of particulate matter. Inflammatory proteins release was analysed in cell medium while differential expression of selected genes was analysed in cells. Significant association of anti-oxidant genes was observed with secondary and aged aerosol, while cytochrome activation with primary and PAHs enriched ultrafine particles. The results obtained clearly show the opportunity to move from the lab bench to the field for properly understanding the toxicological effects also of ultrafine particles on selected in vitro models. Copyright © 2018 Elsevier Ltd. All rights reserved.

A field evaluation of a piezo-optical dosimeter for environmental monitoring of nitrogen dioxide.

PubMed

Wright, John D; Schillinger, Eric F J; Cazier, Fabrice; Nouali, Habiba; Mercier, Agnes; Beaugard, Charles

2004-06-01

Measurements of 8-hour time-weighted average NO(2) concentrations are reported at 7 different locations in the region of Dunkirk over 5 consecutive days using PiezOptic monitoring badges previously calibrated for the range 0-70 ppb together with data from chemiluminescent analysers in 5 sites (4 fixed and one mobile). The latter facilities also provided data on ozone and NO concentrations and meteorological conditions. Daily averages from the two pairs of badges in different types of sampling cover in each site have been compared with data from the chemiluminescent analysers, and found largely to agree within error margins of +/-30%. Although NO(2) and ozone concentrations were low, rendering detailed discussion impossible, the general features followed expected patterns.

Terra incognita: The unknown risks to environmental quality posed by the spatial distribution and abundance of concentrated animal feeding operations.

PubMed

Martin, Katherine L; Emanuel, Ryan E; Vose, James M

2018-06-18

Concentrated animal feeding operations (CAFOs) pose wide ranging environmental risks to many parts of the US and across the globe, but datasets for CAFO risk assessments are not readily available. Within the United States, some of the greatest concentrations of CAFOs occur in North Carolina. It is also one of the only states with publicly accessible location data for classes of CAFOs that are required to obtain water quality permits from the U.S. Environmental Protection Agency (EPA); however, there are no public data sources for the large number of CAFOs that do not require EPA water quality permits. We combined public records of CAFO locations with data collected in North Carolina by the Waterkeeper and Riverkeeper Alliances to examine the distribution of both permitted and non-permitted CAFOs across the state. Over half (55%) of the state's 6646 CAFOs are located in the Coastal Plain, a low-lying region vulnerable to flooding associated with regular cyclonic and convective storms. We identified 19% of CAFOs ≤ 100 m of the nearest stream, and some as close as 15 m to the nearest stream, a common riparian buffer width for water quality management. Future climate scenarios suggest large storm events are expected to become increasingly extreme, and dry interstorm periods could lengthen. Such extremes could exacerbate the environmental impacts of CAFOs. Understanding the potential impacts of CAFO agroecosystems will require remote sensing to identify CAFOs, fieldwork to determine the extent of environmental footprints, and modeling to identify thresholds that determine environmental risk under changing conditions. Copyright © 2018 Elsevier B.V. All rights reserved.

Estimated probability of arsenic in groundwater from bedrock aquifers in New Hampshire, 2011

USGS Publications Warehouse

Ayotte, Joseph D.; Cahillane, Matthew; Hayes, Laura; Robinson, Keith W.

2012-01-01

The statewide maps generated by the probability models are not designed to predict arsenic concentration in any single well, but they are expected to provide useful information in areas of the State that currently contain little to no data on arsenic concentration. They also may aid in resource decision making, in determining potential risk for private wells, and in ecological-level analysis of disease outcomes. The approach for modeling arsenic in groundwater could also be applied to other environmental contaminants that have potential implications for human health, such as uranium, radon, fluoride, manganese, volatile organic compounds, nitrate, and bacteria.

Online Serum PFOA Calculator for Adults

PubMed Central

2017-01-01

Summary: Perfluorooctanoic acid (PFOA) is a persistent environmental contaminant that has been detected in >100 public water systems in the United States alone. A variety of epidemiological investigations of PFOA have been published, mostly using measured or modeled serum PFOA concentrations as the exposure metric. Comparison of drinking water PFOA concentrations to those study findings or to typical serum concentrations requires pharmacokinetic modeling. This brief communication describes an online Javascript calculator that easily plots the expected serum PFOA concentration over time and at steady state for adults after starting or stopping consumption of PFOA-contaminated water. Two examples of usage are provided, including increasing serum PFOA after ongoing consumption of contaminated water at the federal limit, and decreasing serum PFOA after carbon filtration began in a contaminated water system. https://doi.org/10.1289/EHP2820 PMID:29068316

Comparative effects of pH and Vision herbicide on two life stages of four anuran amphibian species.

PubMed

Edginton, Andrea N; Sheridan, Patrick M; Stephenson, Gerald R; Thompson, Dean G; Boermans, Herman J

2004-04-01

Vision, a glyphosate-based herbicide containing a 15% (weight:weight) polyethoxylated tallow amine surfactant blend, and the concurrent factor of pH were tested to determine their interactive effects on early life-stage anurans. Ninety-six-hour laboratory static renewal studies, using the embryonic and larval life stages (Gosner 25) of Rana clamitans, R. pipiens, Bufo americanus, and Xenopus laevis, were performed under a central composite rotatable design. Mortality and the prevalence of malformations were modeled using generalized linear models with a profile deviance approach for obtaining confidence intervals. There was a significant (p < 0.05) interaction of pH with Vision concentration in all eight models, such that the toxicity of Vision was amplified by elevated pH. The surfactant is the major toxic component of Vision and is hypothesized, in this study, to be the source of the pH interaction. Larvae of B. americanus and R. clamitans were 1.5 to 3.8 times more sensitive than their corresponding embryos, whereas X. laevis and R. pipiens larvae were 6.8 to 8.9 times more sensitive. At pH values above 7.5, the Vision concentrations expected to kill 50% of the test larvae in 96-h (96-h lethal concentration [LC50]) were predicted to be below the expected environmental concentration (EEC) as calculated by Canadian regulatory authorities. The EEC value represents a worst-case scenario for aerial Vision application and is calculated assuming an application of the maximum label rate (2.1 kg acid equivalents [a.e.]/ha) into a pond 15 cm in depth. The EEC of 1.4 mg a.e./L (4.5 mg/L Vision) was not exceeded by 96-h LC50 values for the embryo test. The larvae of the four species were comparable in sensitivity. Field studies should be completed using the more sensitive larval life stage to test for Vision toxicity at actual environmental concentrations.

Impacts and Policy Implications of Metals Effluent Discharge into Rivers within Industrial Zones: A Sub-Saharan Perspective from Ethiopia

NASA Astrophysics Data System (ADS)

Zinabu, E.; Kelderman, P.; van der Kwast, J.; Irvine, K.

2018-04-01

Kombolcha, a city in Ethiopia, exemplifies the challenges and problems of the sub-Saharan countries where industrialization is growing fast but monitoring resources are poor and information on pollution unknown. This study monitored metals Cr, Cu, Zn, and Pb concentrations in five factories' effluents, and in the effluent mixing zones of two rivers receiving discharges during the rainy seasons of 2013 and 2014. The results indicate that median concentrations of Cr in the tannery effluents and Zn in the steel processing effluents were as high as 26,600 and 155,750 µg/L, respectively, much exceeding both the USEPA and Ethiopian emission guidelines. Cu concentrations were low in all effluents. Pb concentrations were high in the tannery effluent, but did not exceed emission guidelines. As expected, no metal emission guidelines were exceeded for the brewery, textile and meat processing effluents. Median Cr and Zn concentrations in the Leyole river in the effluent mixing zones downstream of the tannery and steel processing plant increased by factors of 52 (2660 compared with 51 µg Cr/L) and 5 (520 compared with 110 µg Zn/L), respectively, compared with stations further upstream. This poses substantial ecological risks downstream. Comparison with emission guidelines indicates poor environmental management by industries and regulating institutions. Despite appropriate legislation, no clear measures have yet been taken to control industrial discharges, with apparent mismatch between environmental enforcement and investment policies. Effluent management, treatment technologies and operational capacity of environmental institutions were identified as key improvement areas to adopt progressive sustainable development.

Detection limits of quantitative and digital PCR assays and their influence in presence-absence surveys of environmental DNA

USGS Publications Warehouse

Hunter, Margaret; Dorazio, Robert M.; Butterfield, John S.; Meigs-Friend, Gaia; Nico, Leo; Ferrante, Jason A.

2017-01-01

A set of universal guidelines is needed to determine the limit of detection (LOD) in PCR-based analyses of low concentration DNA. In particular, environmental DNA (eDNA) studies require sensitive and reliable methods to detect rare and cryptic species through shed genetic material in environmental samples. Current strategies for assessing detection limits of eDNA are either too stringent or subjective, possibly resulting in biased estimates of species’ presence. Here, a conservative LOD analysis grounded in analytical chemistry is proposed to correct for overestimated DNA concentrations predominantly caused by the concentration plateau, a nonlinear relationship between expected and measured DNA concentrations. We have used statistical criteria to establish formal mathematical models for both quantitative and droplet digital PCR. To assess the method, a new Grass Carp (Ctenopharyngodon idella) TaqMan assay was developed and tested on both PCR platforms using eDNA in water samples. The LOD adjustment reduced Grass Carp occupancy and detection estimates while increasing uncertainty – indicating that caution needs to be applied to eDNA data without LOD correction. Compared to quantitative PCR, digital PCR had higher occurrence estimates due to increased sensitivity and dilution of inhibitors at low concentrations. Without accurate LOD correction, species occurrence and detection probabilities based on eDNA estimates are prone to a source of bias that cannot be reduced by an increase in sample size or PCR replicates. Other applications also could benefit from a standardized LOD such as GMO food analysis, and forensic and clinical diagnostics.

Morphology, Spatial Distribution, and Concentration of Flame Retardants in Consumer Products and Environmental Dusts using Scanning Electron Microscopy and Raman Micro-spectroscopy

PubMed Central

WAGNER, JEFF; GHOSAL, SUTAPA; WHITEHEAD, TODD; METAYER, CATHERINE

2013-01-01

We characterized flame retardant (FR) morphologies and spatial distributions in 7 consumer products and 7 environmental dusts to determine their implications for transfer mechanisms, human exposure, and the reproducibility of gas chromatography-mass spectrometry (GC-MS) dust measurements. We characterized individual particles using scanning electron microscopy / energy dispersive x-ray spectroscopy (SEM/EDS) and Raman micro-spectroscopy (RMS). Samples were screened for the presence of 3 FR constituents (bromine, phosphorous, non-salt chlorine) and 2 metal synergists (antimony and bismuth). Subsequent analyses of select samples by RMS enabled molecular identification of the FR compounds and matrix materials. The consumer products and dust samples possessed FR elemental weight percents of up to 36% and 31%, respectively. We identified 24 FR-containing particles in the dust samples and classified them into 9 types based on morphology and composition. We observed a broad range of morphologies for these FR-containing particles, suggesting FR transfer to dust via multiple mechanisms. We developed an equation to describe the heterogeneity of FR-containing particles in environmental dust samples. The number of individual FR-containing particles expected in a 1-mg dust sample with a FR concentration of 100 ppm ranged from <1 to >1000 particles. The presence of rare, high-concentration bromine particles was correlated with decabromodiphenyl ether concentrations obtained via GC-MS. When FRs are distributed heterogeneously in highly concentrated dust particles, human exposure to FRs may be characterized by high transient exposures interspersed by periods of low exposure, and GC-MS FR concentrations may exhibit large variability in replicate subsamples. Current limitations of this SEM/EDS technique include potential false negatives for volatile and chlorinated FRs and greater quantitation uncertainty for brominated FR in aluminum-rich matrices. PMID:23739093

Multimedia Environmental Distribution of Nanomaterials

NASA Astrophysics Data System (ADS)

Liu, Haoyang Haven

Engineered nanomaterials (ENMs), which may be released to the environment due to human-related activities, can move across environmental phase boundaries and be found in most media. Given the rapid development and growing applications of nanotechnology, there is concern and thus the need to assess the potential environmental impact associated with ENMs. Accordingly, a modeling platform was developed to enable evaluation of the dynamic multimedia environmental distribution of ENMs (MendNano) and the range of potential exposure concentrations of ENMs. The MendNano was based on a dynamic multimedia compartmental modeling approach that was guided by detailed analysis of the agglomeration of ENMs, life-cycle analysis based estimates of their potential release to the environment, and incorporation of mechanistic sub-models of various intermedia transport processes. Model simulations for various environmental scenarios indicated that ENM accumulation in the sediment increased significantly with increased ENMs attachment to suspended solids in water. Atmospheric dry and wet depositions can be important pathways for ENMs input to the terrestrial environment in the absence of direct and distributed ENM release to soil. Increased ENM concentration in water due to atmospheric deposition (wet and dry) is expected as direct ENM release to water diminishes. However, for soluble ENMs dissolution can be the dominant pathway for suspended ENM removal from water even compared to advective transport. For example, simulations for Los Angeles showed that dry deposition, rain scavenging, and wind dilution can remove 90% of ENMs from the atmospheric airshed in ~100-230 days, ~2-6 hrs, and ~0.5-2 days, respectively. For the evaluated ENMs (metal, metal oxides, carbon nanotubes (CNT), nanoclays), mass accumulation in the multimedia environment was mostly in the soil and sediment. Additionally, simulation results for TiO2 in Los Angeles demonstrates that the ENM concentrations in air and water increases rapidly to reach steady state, in 72 hrs and 8 days after the start of source release, respectively. After termination of source release, ENM concentrations would decrease by 90% in ~1 and ~4 days. In contrast, steady state for ENM concentrations in soil would not be expected to occur until after about 10 years. MendNano was further integrated with a sub-model of lifecycle environmental assessment for the release of ENMs (LearNano). Estimation of the releases of various ENMs and their environmental distributions in various regions in the U.S. and countries throughout the world revealed that the exposure concentrations for most ENMs (e.g., metal, metal oxides and carbon nanotubes) are expected to be in the range of 0.0003 - 30 ng m-3 (air), 0.006 - 150 ng L-1 (water), 0.01 - 40 mug kg-1 (soil), and 0.005 - 100 mg kg-1 (sediment). It is important to note that the environmental transport of ENMs is governed by particulate transport processes; and thus the transport rates of ENMs are dependent on their particle size distribution. Accordingly, a computational constant-number Direct Simulation Monte Carlo (DSMC) model was also developed to assess the ENM agglomeration in aqueous systems, by solving the Smoluchowski coagulation equation coupled with particle-particle interaction energies provided by the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and non-DLVO hydration repulsion interaction energy. Prediction of ENM agglomerate PSDs demonstrated excellent agreement with experimental measurements for TiO 2, CeO2, alpha-Fe2O3, SiO2, and C60 ENMs over a wide range suspension conditions. Simulations also demonstrated, in quantitative agreement with DLS measurements, that nanoparticle agglomerate size increased both with ionic strength (IS) and as the solution pH approached the isoelectric point (IEP). Additionally, evaluation of experimental DLS measurements for TiO2, CeO2, SiO2, and alpha-Fe 2O3 (hematite) at high IS (up to 900 mM) or low |zeta-potential| (>=1.35 mV) revealed that non-DLVO hydration repulsion energy can be above electrostatic repulsion energy such that the increased overall repulsion energy (contributed by hydration repulsion energy) can significantly lower the agglomerate diameter relative to the classical DLVO prediction. The classical DLVO theory, which is reasonably applicable for agglomeration of NPs of high |zeta-potential| (~>35 mV) in suspensions of low IS (~1 mM) or low |zeta-potential| (~< 40 mV) conditions. In summary, the MendNano-LearNano integrated modeling platform was implemented as a web-based software application that enables rapid "what-if?" scenario analysis, in order to assess the response of environmental system to various scenarios of ENM releases, investigate the impact of geographical and meteorological parameters on ENM distribution in the environment, compare the impact of ENM production and potential releases on different regions, as well as estimate source release rates based on monitored ENM concentrations. It is envisioned that the present integrated modeling platform can serve as a decision support tool to rapidly and critically assess the potential environmental implications of ENMs and thus ensure that nanotechnology is developed in a productive and environmentally responsible manner.

Spatiotemporal Variability of Dimethylsulphoniopropionate on a Fringing Coral Reef: The Role of Reefal Carbonate Chemistry and Environmental Variability

PubMed Central

Burdett, Heidi L.; Donohue, Penelope J. C.; Hatton, Angela D.; Alwany, Magdy A.; Kamenos, Nicholas A.

2013-01-01

Oceanic pH is projected to decrease by up to 0.5 units by 2100 (a process known as ocean acidification, OA), reducing the calcium carbonate saturation state of the oceans. The coastal ocean is expected to experience periods of even lower carbonate saturation state because of the inherent natural variability of coastal habitats. Thus, in order to accurately project the impact of OA on the coastal ocean, we must first understand its natural variability. The production of dimethylsulphoniopropionate (DMSP) by marine algae and the release of DMSP’s breakdown product dimethylsulphide (DMS) are often related to environmental stress. This study investigated the spatiotemporal response of tropical macroalgae (Padina sp., Amphiroa sp. and Turbinaria sp.) and the overlying water column to natural changes in reefal carbonate chemistry. We compared macroalgal intracellular DMSP and water column DMSP+DMS concentrations between the environmentally stable reef crest and environmentally variable reef flat of the fringing Suleman Reef, Egypt, over 45-hour sampling periods. Similar diel patterns were observed throughout: maximum intracellular DMSP and water column DMS/P concentrations were observed at night, coinciding with the time of lowest carbonate saturation state. Spatially, water column DMS/P concentrations were highest over areas dominated by seagrass and macroalgae (dissolved DMS/P) and phytoplankton (particulate DMS/P) rather than corals. This research suggests that macroalgae may use DMSP to maintain metabolic function during periods of low carbonate saturation state. In the reef system, seagrass and macroalgae may be more important benthic producers of dissolved DMS/P than corals. An increase in DMS/P concentrations during periods of low carbonate saturation state may become ecologically important in the future under an OA regime, impacting larval settlement and increasing atmospheric emissions of DMS. PMID:23724073

Plant zonation in a tropical irregular estuary: can large occurrence zones be explained by a tradeoff model?

PubMed

Ribeiro, J P N; Matsumoto, R S; Takao, L K; Lima, M I S

2015-08-01

Estuaries present an environmental gradient that ranges from almost fresh water conditions to almost marine conditions. Salinity and flooding are the main abiotic drivers for plants. Therefore, plant zonation in estuaries is closely related to the tidal cycles. It is expected that the competitive abilities of plants would be inversely related to the tolerance toward environmental stress (tradeoff). Thus, in estuaries, plant zonation tends to be controlled by the environment near the sandbar and by competition away from it. This zonation pattern has been proposed for regular non-tropical estuaries. For tropical estuaries, the relative importance of rain is higher, and it is not clear to what extent this model can be extrapolated. We measured the tidal influence along the environmental gradient of a tropical irregular estuary and quantified the relative importance of the environment and the co-occurrence degree. Contrary to the narrow occurrence zone that would be expected for regular estuaries, plants presented large occurrence zones. However, the relative importance of the environment and competition followed the same patterns proposed for regular estuaries. The environmental conditions allow plants to occur in larger zones, but these zones arise from smaller and infrequent patches distributed across a larger area, and most species populations are concentrated in relatively narrow zones. Thus, we concluded that the zonation pattern in the Massaguaçu River estuary agrees with the tradeoff model.

Modeling short-term concentration fluctuations of semi-volatile pollutants in the soil-plant-atmosphere system.

PubMed

Bao, Zhongwen; Haberer, Christina M; Maier, Uli; Beckingham, Barbara; Amos, Richard T; Grathwohl, Peter

2016-11-01

Temperature changes can drive cycling of semi-volatile pollutants between different environmental compartments (e.g. atmosphere, soil, plants). To evaluate the impact of daily temperature changes on atmospheric concentration fluctuations we employed a physically based model coupling soil, plants and the atmosphere, which accounts for heat transport, effective gas diffusion, sorption and biodegradation in the soil as well as eddy diffusion and photochemical oxidation in the atmospheric boundary layer of varying heights. The model results suggest that temperature-driven re-volatilization and uptake in soils cannot fully explain significant diurnal concentration fluctuations of atmospheric pollutants as for example observed for polychlorinated biphenyls (PCBs). This holds even for relatively low water contents (high gas diffusivity) and high sorption capacity of the topsoil (high organic carbon content and high pollutant concentration in the topsoil). Observed concentration fluctuations, however, can be easily matched if a rapidly-exchanging environmental compartment, such as a plant layer, is introduced. At elevated temperatures, plants release organic pollutants, which are rapidly distributed in the atmosphere by eddy diffusion. For photosensitive compounds, e.g. some polycyclic aromatic hydrocarbons (PAHs), decreasing atmospheric concentrations would be expected during daytime for the bare soil scenario. This decline is buffered by a plant layer, which acts as a ground-level reservoir. The modeling results emphasize the importance of a rapidly-exchanging compartment above ground to explain short-term atmospheric concentration fluctuations. Copyright © 2016 Elsevier B.V. All rights reserved.

Concentration-dependent polyparameter linear free energy relationships to predict organic compound sorption on carbon nanotubes

PubMed Central

Zhao, Qing; Yang, Kun; Li, Wei; Xing, Baoshan

2014-01-01

Adsorption of organic compounds on carbon nanotubes (CNTs), governed by interactions between molecules and CNTs surfaces, is critical for their fate, transport, bioavailability and toxicity in the environment. Here, we report a promising concentration-dependent polyparameter linear free energy relationships (pp-LFERs) model to describe the compound-CNTs interactions and to predict sorption behavior of chemicals on CNTs in a wide range of concentrations (over five orders of magnitude). The developed pp-LFERs are able to capture the dependence of the ki on equilibrium concentration. The pp-LFERs indexes [r, p, a, b, v] representing different interactions are found to have a good relationship with the aqueous equilibrium concentrations of compounds. This modified model can successfully interpret the relative contribution of each interaction at a given concentration and reliably predict sorption of various chemicals on CNTs. This approach is expected to help develop a better environmental fate and risk assessment model. PMID:24463462

Chemical gradients in sediment cores from an EPA reference site off the Farallon Islands - Assessing chemical indicators of dredged material disposal in the deep sea

USGS Publications Warehouse

Bothner, Michael H.; Gill, P.W.; Boothman, W.S.; Taylor, B.B.; Karl, Herman A.

1998-01-01

Heavy metal and organic contaminants have been determined in undisturbed sediment cores from the US Environmental Protection Agency reference site for dredged material on the continental slope off San Francisco. As expected, the concentrations are significantly lower than toxic effects guidelines, but concentrations of PCBs, PAHs, Hg, Pb, and Clostridium perfringens (a bacterium spore found in sewage) were nearly two or more times greater in the surface sediments than in intervals deeper in the cores. These observations indicate the usefulness of measuring concentration gradients in sediments at the San Francisco deep ocean disposal site (SF-DODS) where a thin (0.5 cm thick) layer of dredged material has been observed beyond the boundary. This thin layer has not been chemically characterized by the common practice of homogenizing over the top 10 cm. An estimated 300 million cubic yards of dredged material from San Francisco Bay are expected to be discharged at the SF-DODS site during the next 50 years. Detailed depth analysis of sediment cores would add significant new information about the fate and effects of dredged material in the deep sea.

A regional assessment of chemicals of concern in surface waters of four Midwestern United States national parks

USGS Publications Warehouse

Elliott, Sarah M.; VanderMeulen, David

2017-01-01

Anthropogenic chemicals and their potential for adverse biological effects raise concern for aquatic ecosystem health in protected areas. During 2013–15, surface waters of four Midwestern United States national parks were sampled and analyzed for wastewater indicators, pharmaceuticals, personal care products, and pesticides. More chemicals and higher concentrations were detected at the two parks with greater urban influences (Mississippi National River and Recreation Area and Indiana Dunes National Lakeshore) than at the two more remote parks (Apostle Islands National Lakeshore and Isle Royale National Park). Atrazine (10–15 ng/L) and N,N-diethyl-meta-toluamide (16–120 ng/L) were the only chemicals detected in inland lakes of a remote island national park (Isle Royale National Park). Bisphenol A and organophosphate flame retardants were commonly detected at the other sampled parks. Gabapentin and simazine had the highest observed concentrations (> 1000 ng/L) in three and two samples, respectively. At the two parks with urban influences, metolachlor and simazine concentrations were similar to those reported for other major urban rivers in the United States. Environmental concentrations of detected chemicals were often orders of magnitude less than standards or reference values with three exceptions: (1) hydrochlorothiazide exceeded a human health-based screening value in seven samples, (2) estrone exceeded a predicted critical environmental concentration for fish pharmacological effects in one sample, and (3) simazine was approaching the 4000 ng/L Maximum Contaminant Level in one sample even though this concentration is not expected to reflect peak pesticide use. Although few environmental concentrations were approaching or exceeded standards or reference values, concentrations were often in ranges reported to elicit effects in aquatic biota. Data from this study will assist in establishing a baseline for chemicals of concern in Midwestern national parks and highlight the need to better understand the sources, pathways, and potential adverse effects to aquatic systems in national parks.

A regional assessment of chemicals of concern in surface waters of four Midwestern United States national parks.

PubMed

Elliott, Sarah M; VanderMeulen, David D

2017-02-01

Anthropogenic chemicals and their potential for adverse biological effects raise concern for aquatic ecosystem health in protected areas. During 2013-15, surface waters of four Midwestern United States national parks were sampled and analyzed for wastewater indicators, pharmaceuticals, personal care products, and pesticides. More chemicals and higher concentrations were detected at the two parks with greater urban influences (Mississippi National River and Recreation Area and Indiana Dunes National Lakeshore) than at the two more remote parks (Apostle Islands National Lakeshore and Isle Royale National Park). Atrazine (10-15ng/L) and N,N-diethyl-meta-toluamide (16-120ng/L) were the only chemicals detected in inland lakes of a remote island national park (Isle Royale National Park). Bisphenol A and organophosphate flame retardants were commonly detected at the other sampled parks. Gabapentin and simazine had the highest observed concentrations (>1000ng/L) in three and two samples, respectively. At the two parks with urban influences, metolachlor and simazine concentrations were similar to those reported for other major urban rivers in the United States. Environmental concentrations of detected chemicals were often orders of magnitude less than standards or reference values with three exceptions: (1) hydrochlorothiazide exceeded a human health-based screening value in seven samples, (2) estrone exceeded a predicted critical environmental concentration for fish pharmacological effects in one sample, and (3) simazine was approaching the 4000ng/L Maximum Contaminant Level in one sample even though this concentration is not expected to reflect peak pesticide use. Although few environmental concentrations were approaching or exceeded standards or reference values, concentrations were often in ranges reported to elicit effects in aquatic biota. Data from this study will assist in establishing a baseline for chemicals of concern in Midwestern national parks and highlight the need to better understand the sources, pathways, and potential adverse effects to aquatic systems in national parks. Copyright © 2016. Published by Elsevier B.V.

Environmental factors and flow paths related to Escherichia coli concentrations at two beaches on Lake St. Clair, Michigan, 2002–2005

USGS Publications Warehouse

Holtschlag, David J.; Shively, Dawn; Whitman, Richard L.; Haack, Sheridan K.; Fogarty, Lisa R.

2008-01-01

Regression analyses and hydrodynamic modeling were used to identify environmental factors and flow paths associated with Escherichia coli (E. coli) concentrations at Memorial and Metropolitan Beaches on Lake St. Clair in Macomb County, Mich. Lake St. Clair is part of the binational waterway between the United States and Canada that connects Lake Huron with Lake Erie in the Great Lakes Basin. Linear regression, regression-tree, and logistic regression models were developed from E. coli concentration and ancillary environmental data. Linear regression models on log10 E. coli concentrations indicated that rainfall prior to sampling, water temperature, and turbidity were positively associated with bacteria concentrations at both beaches. Flow from Clinton River, changes in water levels, wind conditions, and log10 E. coli concentrations 2 days before or after the target bacteria concentrations were statistically significant at one or both beaches. In addition, various interaction terms were significant at Memorial Beach. Linear regression models for both beaches explained only about 30 percent of the variability in log10 E. coli concentrations. Regression-tree models were developed from data from both Memorial and Metropolitan Beaches but were found to have limited predictive capability in this study. The results indicate that too few observations were available to develop reliable regression-tree models. Linear logistic models were developed to estimate the probability of E. coli concentrations exceeding 300 most probable number (MPN) per 100 milliliters (mL). Rainfall amounts before bacteria sampling were positively associated with exceedance probabilities at both beaches. Flow of Clinton River, turbidity, and log10 E. coli concentrations measured before or after the target E. coli measurements were related to exceedances at one or both beaches. The linear logistic models were effective in estimating bacteria exceedances at both beaches. A receiver operating characteristic (ROC) analysis was used to determine cut points for maximizing the true positive rate prediction while minimizing the false positive rate. A two-dimensional hydrodynamic model was developed to simulate horizontal current patterns on Lake St. Clair in response to wind, flow, and water-level conditions at model boundaries. Simulated velocity fields were used to track hypothetical massless particles backward in time from the beaches along flow paths toward source areas. Reverse particle tracking for idealized steady-state conditions shows changes in expected flow paths and traveltimes with wind speeds and directions from 24 sectors. The results indicate that three to four sets of contiguous wind sectors have similar effects on flow paths in the vicinity of the beaches. In addition, reverse particle tracking was used for transient conditions to identify expected flow paths for 10 E. coli sampling events in 2004. These results demonstrate the ability to track hypothetical particles from the beaches, backward in time, to likely source areas. This ability, coupled with a greater frequency of bacteria sampling, may provide insight into changes in bacteria concentrations between source and sink areas.

N cycling in SPRUCE (Spruce Peatlands Response Under ...

EPA Pesticide Factsheets

Peatlands located in boreal regions make up a third of global wetland area and are expected to have the highest temperature increases in response to climate change. As climate warms, we expect peat decomposition may accelerate, altering the cycling of nitrogen. Alterations in the nitrogen cycle can have consequences on NO3, NH4 availability or pollution, and potentially increase nitrous oxide (N2O) emissions, a persistent greenhouse gas (GHG). These consequences can cascade to altering whole ecosystem functions and effecting human health.We are investigating nitrogen cycling response to elevated temperature and CO2 in a boreal peatland. Spruce and Peatland Responses Under Climate and Environmental Change (SPRUCE) project initiated soil warming in 2014 in ten peatland mesocosms (five temperature treatments from ambient (+0°C) to +9°C) and elevated CO2 in half of the mesocosms in 2016. Peat cores at three depths (acrotelm, catotelm, deep peat) were analyzed in the laboratory for denitrification, nitrification, and ammonification. We expect denitrification, nitrification, and ammonification rates to increase, and denitrification efficiency to decrease with rising temperatures- potentially contaminating water resources with NO3, NH4 and increase N2O concentrations in our atmosphere. This research will enhance the scientific understanding of how nitrogen cycling, an important functional eco-service, responds under environmental conditions including elevated CO2

Deep-sea oil plume enriches psychrophilic oil-degrading bacteria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hazen, T.C.; Dubinsky, E.A.; DeSantis, T.Z.

The biological effects and expected fate of the vast amount of oil in the Gulf of Mexico from the Deepwater Horizon blowout are unknown owing to the depth and magnitude of this event. Here, we report that the dispersed hydrocarbon plume stimulated deep-sea indigenous {gamma}-Proteobacteria that are closely related to known petroleum degraders. Hydrocarbon-degrading genes coincided with the concentration of various oil contaminants. Changes in hydrocarbon composition with distance from the source and incubation experiments with environmental isolates demonstrated faster-than-expected hydrocarbon biodegradation rates at 5 C. Based on these results, the potential exists for intrinsic bioremediation of the oil plumemore » in the deep-water column without substantial oxygen drawdown.« less

Approaches for derivation of environmental quality criteria for substances applied in risk assessment of discharges from offshore drilling operations.

PubMed

Altin, Dag; Frost, Tone Karin; Nilssen, Ingunn

2008-04-01

In order to achieve the offshore petroleum industries "zero harm" goal to the environment, the environmental impact factor for drilling discharges was developed as a tool to identify and quantify the environmental risks associated with disposal of drilling discharges to the marine environment. As an initial step in this work the main categories of substances associated with drilling discharges and assumed to contribute to toxic or nontoxic stress were identified and evaluated for inclusion in the risk assessment. The selection were based on the known toxicological properties of the substances, or the total amount discharged together with their potential for accumulation in the water column or sediments to levels that could be expected to cause toxic or nontoxic stress to the biota. Based on these criteria 3 categories of chemicals were identified for risk assessment the water column and sediments: Natural organic substances, metals, and drilling fluid chemicals. Several approaches for deriving the environmentally safe threshold concentrations as predicted no effect concentrations were evaluated in the process. For the water column consensus were reached for using the species sensitivity distribution approach for metals and the assessment factor approach for natural organic substances and added drilling chemicals. For the sediments the equilibrium partitioning approach was selected for all three categories of chemicals. The theoretically derived sediment quality criteria were compared to field-derived threshold effect values based on statistical approaches applied on sediment monitoring data from the Norwegian Continental Shelf. The basis for derivation of predicted no effect concentration values for drilling discharges should be consistent with the principles of environmental risk assessment as described in the Technical Guidance Document on Risk Assessment issued by the European Union.

Role of soil-to-leaf tritium transfer in controlling leaf tritium dynamics: Comparison of experimental garden and tritium-transfer model results.

PubMed

Ota, Masakazu; Kwamena, Nana-Owusua A; Mihok, Steve; Korolevych, Volodymyr

2017-11-01

Environmental transfer models assume that organically-bound tritium (OBT) is formed directly from tissue-free water tritium (TFWT) in environmental compartments. Nevertheless, studies in the literature have shown that measured OBT/HTO ratios in environmental samples are variable and generally higher than expected. The importance of soil-to-leaf HTO transfer pathway in controlling the leaf tritium dynamics is not well understood. A model inter-comparison of two tritium transfer models (CTEM-CLASS-TT and SOLVEG-II) was carried out with measured environmental samples from an experimental garden plot set up next to a tritium-processing facility. The garden plot received one of three different irrigation treatments - no external irrigation, irrigation with low tritium water and irrigation with high tritium water. The contrast between the results obtained with the different irrigation treatments provided insights into the impact of soil-to-leaf HTO transfer on the leaf tritium dynamics. Concentrations of TFWT and OBT in the garden plots that were not irrigated or irrigated with low tritium water were variable, responding to the arrival of the HTO-plume from the tritium-processing facility. In contrast, for the plants irrigated with high tritium water, the TFWT concentration remained elevated during the entire experimental period due to a continuous source of high HTO in the soil. Calculated concentrations of OBT in the leaves showed an initial increase followed by quasi-equilibration with the TFWT concentration. In this quasi-equilibrium state, concentrations of OBT remained elevated and unchanged despite the arrivals of the plume. These results from the model inter-comparison demonstrate that soil-to-leaf HTO transfer significantly affects tritium dynamics in leaves and thereby OBT/HTO ratio in the leaf regardless of the atmospheric HTO concentration, only if there is elevated HTO concentrations in the soil. The results of this work indicate that assessment models should be refined to consider the importance of soil-to-leaf HTO transfer to ensure that dose estimates are accurate and conservative. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fate and effects of clothianidin in fields using conservation practices.

PubMed

de Perre, Chloé; Murphy, Tracye M; Lydy, Michael J

2015-02-01

Despite the extensive use of the neonicotinoid insecticide clothianidin, and its known toxicity to beneficial insects such as pollinators, little attention has been given to its fate under agricultural field conditions. The present study investigated the fate and toxicity of clothianidin applied every other year as a corn seed-coating at 2 different rates, 0.25 mg/seed and 0.50 mg/seed, in an agricultural field undergoing a corn-soybean annual rotation, and conservation tillage. Concentrations were measured in soil, surface runoff, infiltration, and groundwater from 2011 to 2013. Clothianidin was detected at low concentrations in soil and water throughout the 2-yr corn and soybean rotation. Low and no-tillage had little or no effect on clothianidin concentrations. Laboratory toxicity bioassays were performed on nontarget species, including Daphnia magna, Hyalella azteca, Chironomus dilutus, Pimephales promelas and Eisenia fetida. Risk quotients were calculated from clothianidin concentrations measured in the field and compared with the laboratory toxicity bioassay results to assess the environmental risk of the insecticide. The risk quotient was found to be lower than the level of concern for C. dilutus, which was the most sensitive species tested; therefore, no short-term environmental risk was expected for the species investigated in the present study. © 2014 SETAC.

Organophosphonates: A review on environmental relevance, biodegradability and removal in wastewater treatment plants.

PubMed

Rott, Eduard; Steinmetz, Heidrun; Metzger, Jörg W

2018-02-15

The worldwide increasing consumption of the phosphonates 2-phosphonobutane-1,2,4-tricarboxylic acid [PBTC], 1-hydroxyethane 1,1-diphosphonic acid [HEDP], nitrilotris(methylene phosphonic acid) [NTMP], ethylenediamine tetra(methylene phosphonic acid) [EDTMP] and diethylenetriamine penta(methylene phosphonic acid) [DTPMP] over the past decades put phosphonates into focus of environmental scientists and agencies, as they are increasingly discussed in the context of various environmental problems. The hitherto difficult analysis of phosphonates contributed to the fact that very little is known about their concentrations and behavior in the environment. This work critically reviews the existing literature up to the year 2016 on the potential environmental relevance of phosphonates, their biotic and abiotic degradability, and their removal in wastewater treatment plants (WWTPs). Accordingly, despite their stability against biological degradation, phosphonates can be removed with relatively high efficiency (>80%) in WWTPs operated with chemical phosphate precipitation. In the literature, however, to our knowledge, there is no information as to whether an enhanced biological phosphorus removal alone is sufficient for such high removal rates and whether the achievable phosphonate concentrations in effluents are sufficiently low to prevent eutrophication. It is currently expected that phosphonates, although being complexing agents, do not remobilize heavy metals from sediments in a significant amount since the phosphonate concentrations required for this (>50μg/L) are considerably higher than the concentrations determined in surface waters. Various publications also point out that phosphonates are harmless to a variety of aquatic organisms. Moreover, degradation products thereof such as N-(phosphonomethyl)glycine and aminomethylphosphonic acid are regarded as being particularly critical. Despite their high stability against biological degradation, phosphonates contribute to eutrophication due to abiotic degradation (mainly photolysis). Furthermore, the literature reports on the fact that phosphonates in high concentrations interfere with phosphate precipitation in WWTPs. Thus, it is recommended to remove phosphonates, in particular from industrial wastewaters, before discharging them into water bodies or WWTPs. Copyright © 2017 Elsevier B.V. All rights reserved.

Selected elements in major minerals from bituminous coal as determined by INAA: Implications for removing environmentally sensitive elements from coal

USGS Publications Warehouse

Palmer, C.A.; Lyons, P.C.

1996-01-01

The four most abundant minerals generally found in Euramerican bituminous coals are quartz, kaolinite, illite and pyrite. These four minerals were isolated by density separation and handpicking from bituminous coal samples collected in the Ruhr Basin, Germany and the Appalachian basin, U.S.A. Trace-element concentrations of relatively pure (??? 99+%) separates of major minerals from these coals were determined directly by using instrumental neutron activation analysis (INAA). As expected, quartz contributes little to the trace-element mass balance. Illite generally has higher trace-element concentrations than kaolinite, but, for the concentrates analyzed in this study, Hf, Ta, W, Th and U are in lower concentrations in illite than in kaolinite. Pyrite has higher concentrations of chalcophile elements (e.g., As and Se) and is considerably lower in lithophile elements as compared to kaolinite and illite. Our study provides a direct and sensitive method of determining trace-element relationships with minerals in coal. Mass-balance calculations suggest that the trace-element content of coal can be explained mainly by three major minerals: pyrite, kaolinite and illite. This conclusion indicates that the size and textural relationships of these major coal minerals may be a more important consideration as to whether coal cleaning can effectively remove the most environmentally sensitive trace elements in coal than what trace minerals are present.

Environmental DNA as a ‘Snapshot’ of Fish Distribution: A Case Study of Japanese Jack Mackerel in Maizuru Bay, Sea of Japan

PubMed Central

Takahashi, Kohji; Sawada, Hideki; Murakami, Hiroaki; Tsuji, Satsuki; Hashizume, Hiroki; Kubonaga, Shou; Horiuchi, Tomoya; Hongo, Masamichi; Nishida, Jo; Okugawa, Yuta; Fujiwara, Ayaka; Fukuda, Miho; Hidaka, Shunsuke; Suzuki, Keita W.; Miya, Masaki; Araki, Hitoshi; Yamanaka, Hiroki; Maruyama, Atsushi; Miyashita, Kazushi; Masuda, Reiji; Minamoto, Toshifumi; Kondoh, Michio

2016-01-01

Recent studies in streams and ponds have demonstrated that the distribution and biomass of aquatic organisms can be estimated by detection and quantification of environmental DNA (eDNA). In more open systems such as seas, it is not evident whether eDNA can represent the distribution and biomass of aquatic organisms because various environmental factors (e.g., water flow) are expected to affect eDNA distribution and concentration. To test the relationships between the distribution of fish and eDNA, we conducted a grid survey in Maizuru Bay, Sea of Japan, and sampled surface and bottom waters while monitoring biomass of the Japanese jack mackerel (Trachurus japonicus) using echo sounder technology. A linear model showed a high R2 value (0.665) without outlier data points, and the association between estimated eDNA concentrations from the surface water samples and echo intensity was significantly positive, suggesting that the estimated spatial variation in eDNA concentration can reflect the local biomass of the jack mackerel. We also found that a best-fit model included echo intensity obtained within 10–150 m from water sampling sites, indicating that the estimated eDNA concentration most likely reflects fish biomass within 150 m in the bay. Although eDNA from a wholesale fish market partially affected eDNA concentration, we conclude that eDNA generally provides a ‘snapshot’ of fish distribution and biomass in a large area. Further studies in which dynamics of eDNA under field conditions (e.g., patterns of release, degradation, and diffusion of eDNA) are taken into account will provide a better estimate of fish distribution and biomass based on eDNA. PMID:26933889

Detection limits of quantitative and digital PCR assays and their influence in presence-absence surveys of environmental DNA.

PubMed

Hunter, Margaret E; Dorazio, Robert M; Butterfield, John S S; Meigs-Friend, Gaia; Nico, Leo G; Ferrante, Jason A

2017-03-01

A set of universal guidelines is needed to determine the limit of detection (LOD) in PCR-based analyses of low-concentration DNA. In particular, environmental DNA (eDNA) studies require sensitive and reliable methods to detect rare and cryptic species through shed genetic material in environmental samples. Current strategies for assessing detection limits of eDNA are either too stringent or subjective, possibly resulting in biased estimates of species' presence. Here, a conservative LOD analysis grounded in analytical chemistry is proposed to correct for overestimated DNA concentrations predominantly caused by the concentration plateau, a nonlinear relationship between expected and measured DNA concentrations. We have used statistical criteria to establish formal mathematical models for both quantitative and droplet digital PCR. To assess the method, a new Grass Carp (Ctenopharyngodon idella) TaqMan assay was developed and tested on both PCR platforms using eDNA in water samples. The LOD adjustment reduced Grass Carp occupancy and detection estimates while increasing uncertainty-indicating that caution needs to be applied to eDNA data without LOD correction. Compared to quantitative PCR, digital PCR had higher occurrence estimates due to increased sensitivity and dilution of inhibitors at low concentrations. Without accurate LOD correction, species occurrence and detection probabilities based on eDNA estimates are prone to a source of bias that cannot be reduced by an increase in sample size or PCR replicates. Other applications also could benefit from a standardized LOD such as GMO food analysis and forensic and clinical diagnostics. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

A new time-series methodology for estimating relationships between elderly frailty, remaining life expectancy, and ambient air quality.

PubMed

Murray, Christian J; Lipfert, Frederick W

2012-01-01

Many publications estimate short-term air pollution-mortality risks, but few estimate the associated changes in life-expectancies. We present a new methodology for analyzing time series of health effects, in which prior frailty is assumed to precede short-term elderly nontraumatic mortality. The model is based on a subpopulation of frail individuals whose entries and exits (deaths) are functions of daily and lagged environmental conditions: ambient temperature/season, airborne particles, and ozone. This frail susceptible population is unknown; its fluctuations cannot be observed but are estimated using maximum-likelihood methods with the Kalman filter. We used an existing 14-y set of daily data to illustrate the model and then tested the assumption of prior frailty with a new generalized model that estimates the portion of the daily death count allocated to nonfrail individuals. In this demonstration dataset, new entries into the high-risk pool are associated with lower ambient temperatures and higher concentrations of particulate matter and ozone. Accounting for these effects on antecedent frailty reduces this at-risk population, yielding frail life expectancies of 5-7 days. Associations between environmental factors and entries to the at-risk pool are about twice as strong as for mortality. Nonfrail elderly deaths are seen to make only small contributions. This new model predicts a small short-lived frail population-at-risk that is stable over a wide range of environmental conditions. The predicted effects of pollution on new entries and deaths are robust and consistent with conventional morbidity/mortality times-series studies. We recommend model verification using other suitable datasets.

Environmentally relevant microplastic exposure affects sediment-dwelling bivalves.

PubMed

Bour, Agathe; Haarr, Ane; Keiter, Steffen; Hylland, Ketil

2018-05-01

Most microplastics are expected to sink and end up in marine sediments. However, very little is known concerning their potential impact on sediment-dwelling organisms. We studied the long-term impact of microplastic exposure on two sediment-dwelling bivalve species. Ennucula tenuis and Abra nitida were exposed to polyethylene microparticles at three concentrations (1; 10 and 25 mg/kg of sediment) for four weeks. Three size classes (4-6; 20-25 and 125-500 μm) were used to study the influence of size on microplastic ecotoxicity. Microplastic exposure did not affect survival, condition index or burrowing behaviour in either bivalve species. However, significant changes in energy reserves were observed. No changes were observed in protein, carbohydrate or lipid contents in E. tenuis, with the exception of a decrease in lipid content for one condition. However, total energy decreased in a dose-dependent manner for bivalves exposed to the largest particles. To the contrary, no significant changes in total energy were observed for A. nitida, although a significant decrease of protein content was observed for individuals exposed to the largest particles, at all concentrations. Concentration and particle size significantly influenced microplastic impacts on bivalves, the largest particles and higher concentrations leading to more severe effects. Several hypotheses are presented to explain the observed modulation of energy reserves, including the influence of microplastic size and concentration. Our results suggest that long-term exposure to microplastics at environmentally relevant concentrations can impact marine benthic biota. Copyright © 2018 Elsevier Ltd. All rights reserved.

Assessment of ambient background concentrations of elements in soil using combined survey and open-source data.

PubMed

Mikkonen, Hannah G; Clarke, Bradley O; Dasika, Raghava; Wallis, Christian J; Reichman, Suzie M

2017-02-15

Understanding ambient background concentrations in soil, at a local scale, is an essential part of environmental risk assessment. Where high resolution geochemical soil surveys have not been undertaken, soil data from alternative sources, such as environmental site assessment reports, can be used to support an understanding of ambient background conditions. Concentrations of metals/metalloids (As, Mn, Ni, Pb and Zn) were extracted from open-source environmental site assessment reports, for soils derived from the Newer Volcanics basalt, of Melbourne, Victoria, Australia. A manual screening method was applied to remove samples that were indicated to be contaminated by point sources and hence not representative of ambient background conditions. The manual screening approach was validated by comparison to data from a targeted background soil survey. Statistical methods for exclusion of contaminated samples from background soil datasets were compared to the manual screening method. The statistical methods tested included the Median plus Two Median Absolute Deviations, the upper whisker of a normal and log transformed Tukey boxplot, the point of inflection on a cumulative frequency plot and the 95th percentile. We have demonstrated that where anomalous sample results cannot be screened using site information, the Median plus Two Median Absolute Deviations is a conservative method for derivation of ambient background upper concentration limits (i.e. expected maximums). The upper whisker of a boxplot and the point of inflection on a cumulative frequency plot, were also considered adequate methods for deriving ambient background upper concentration limits, where the percentage of contaminated samples is <25%. Median ambient background concentrations of metals/metalloids in the Newer Volcanic soils of Melbourne were comparable to ambient background concentrations in Europe and the United States, except for Ni, which was naturally enriched in the basalt-derived soils of Melbourne. Copyright © 2016 Elsevier B.V. All rights reserved.

Risk Assessment for Criteria Pollutants and Air Toxics in two Sites of Mexico City During 2003 Field Campaign

NASA Astrophysics Data System (ADS)

García, A. R.; Grutter, M. M.; Volkamer, R. M.

2007-05-01

An environmental risk assessment for criteria pollutants and air toxics in Mexico City is presented. The data used in the study were collected by FTIR and DOAS systems during the Mexico City Metropolitan Area field campaign on April 2003 (MCMA2003). The systems were deployed in two different sites: One in downtown (Merced) and the other in the south east (CENICA). Concentrations of criteria pollutants and air toxics were obtained every 5 min and were used to obtain hourly average concentrations and the month average for April. The concentration values were used to estimate the risks of acute and chronic exposure to ambient concentrations using risk measures like hazard index, life cancer probability, life lost expectancy and maximum individual cancer risk. Results revealed that both sites have similar risk values. For acute exposure, criteria pollutants have larger risks than air toxics, but air toxics have larger risks for chronic exposure. Ambient concentrations of benzene showed the largest carcinogenic risk of the measured air toxics.

Consequences of synergy between environmental carcinogens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berenbaum, M.C.

1985-12-01

As it is generally impossible to determine dose-response relationships for carcinogens at the low concentrations in which they occur in the environment, risk-benefit considerations are by consensus based on the linear, no-threshold model, on the assumption that this represents the worst case. However, this assumption does not take into account the possibility of synergistic interactions between carcinogens. It is shown here that, as a result of such interactions, the dose-response curve for added risk due to any individual carcinogen will generally be steeper at lower doses than at higher doses, and consequently the risk at low environmental levels will bemore » higher than would be expected from a linear response. Moreover, this excess risk at low doses is shown to increase as the general level of environmental carcinogens rises and, independently of this effect, it may also increase with the number of carcinogens present.« less

Investigation of the environmental impacts of naturally occurring radionuclides in the processing of sulfide ores for gold using gamma spectrometry.

PubMed

Gbadago, J K; Faanhof, A; Darko, E O; Schandorf, C

2011-09-01

The possible environmental impacts of naturally occurring radionuclides on workers and a critical community, as a result of milling and processing sulfide ores for gold by a mining company at Bogoso in the western region of Ghana, have been investigated using gamma spectroscopy. Indicative doses for the workers during sulfide ore processing were calculated from the activity concentrations measured at both physical and chemical processing stages. The dose rate, annual effective dose equivalent, radium equivalent activity, external and internal hazard indices, and radioactivity level index for tailings, for the de-silted sediments of run-off from the vicinity of the tailings dam through the critical community, and for the soils of the critical community's basic schools were calculated and found to be lower than their respective permissible limits. The environmental impact of the radionuclides is therefore expected to be low in this mining environment.

Evaluation of low-cost electro-chemical sensors for environmental monitoring of ozone, nitrogen dioxide, and carbon monoxide.

PubMed

Afshar-Mohajer, Nima; Zuidema, Christopher; Sousan, Sinan; Hallett, Laura; Tatum, Marcus; Rule, Ana M; Thomas, Geb; Peters, Thomas M; Koehler, Kirsten

2018-02-01

Development of an air quality monitoring network with high spatio-temporal resolution requires installation of a large number of air pollutant monitors. However, state-of-the-art monitors are costly and may not be compatible with wireless data logging systems. In this study, low-cost electro-chemical sensors manufactured by Alphasense Ltd. for detection of CO and oxidative gases (predominantly O 3 and NO 2 ) were evaluated. The voltages from three oxidative gas sensors and three CO sensors were recorded every 2.5 sec when exposed to controlled gas concentrations in a 0.125-m 3 acrylic glass chamber. Electro-chemical sensors for detection of oxidative gases demonstrated sensitivity to both NO 2 and O 3 with similar voltages recorded when exposed to equivalent environmental concentrations of NO 2 or O 3 gases, when evaluated separately. There was a strong linear relationship between the recorded voltages and target concentrations of oxidative gases (R 2 > 0.98) over a wide range of concentrations. Although a strong linear relationship was also observed for CO concentrations below 12 ppm, a saturation effect was observed wherein the voltage only changes minimally for higher CO concentrations (12-50 ppm). The nonlinear behavior of the CO sensors implied their unsuitability for environments where high CO concentrations are expected. Using a manufacturer-supplied shroud, sensors were tested at 2 different flow rates (0.25 and 0.5 Lpm) to mimic field calibration of the sensors with zero air and a span gas concentration (2 ppm NO2 or 15 ppm CO). As with all electrochemical sensors, the tested devices were subject to drift with a bias up to 20% after 9 months of continuous operation. Alphasense CO sensors were found to be a proper choice for occupational and environmental CO monitoring with maximum concentration of 12 ppm, especially due to the field-ready calibration capability. Alphasense oxidative gas sensors are usable only if it is valuable to know the sum of the NO 2 and O 3 concentrations.

Peer Deviance, Alcohol Expectancies, and Adolescent Alcohol Use: Explaining Shared and Nonshared Environmental Effects Using an Adoptive Sibling Pair Design

PubMed Central

Samek, Diana R.; Keyes, Margaret A.; Iacono, William G.; McGue, Matt

2013-01-01

Previous research suggests adolescent alcohol use is largely influenced by environmental factors, yet little is known about the specific nature of this influence. We hypothesized that peer deviance and alcohol expectancies would be sources of environmental influence because both have been consistently and strongly correlated with adolescent alcohol use. The sample included 206 genetically related and 407 genetically unrelated sibling pairs assessed in mid-to-late adolescence. The heritability of adolescent alcohol use (e.g., frequency, quantity last 12 months) was minimal and not significantly different from zero. The associations among peer deviance, alcohol expectancies, and alcohol use were primarily due to shared environmental factors. Of special note, alcohol expectancies also significantly explained nonshared environmental influence on alcohol use. This study is one of few that have identified specific environmental variants of adolescent alcohol use while controlling for genetic influence. PMID:23644917

Peer deviance, alcohol expectancies, and adolescent alcohol use: explaining shared and nonshared environmental effects using an adoptive sibling pair design.

PubMed

Samek, Diana R; Keyes, Margaret A; Iacono, William G; McGue, Matt

2013-07-01

Previous research suggests adolescent alcohol use is largely influenced by environmental factors, yet little is known about the specific nature of this influence. We hypothesized that peer deviance and alcohol expectancies would be sources of environmental influence because both have been consistently and strongly correlated with adolescent alcohol use. The sample included 206 genetically related and 407 genetically unrelated sibling pairs assessed in mid-to-late adolescence. The heritability of adolescent alcohol use (e.g., frequency, quantity last 12 months) was minimal and not significantly different from zero. The associations among peer deviance, alcohol expectancies, and alcohol use were primarily due to shared environmental factors. Of special note, alcohol expectancies also significantly explained nonshared environmental influence on alcohol use. This study is one of few that have identified specific environmental variants of adolescent alcohol use while controlling for genetic influence.

Are silver nanoparticles always toxic in the presence of environmental anions?

PubMed

Guo, Zhi; Chen, Guiqiu; Zeng, Guangming; Yan, Ming; Huang, Zhenzhen; Jiang, Luhua; Peng, Chuan; Wang, Jiajia; Xiao, Zhihua

2017-03-01

Increasing amounts of silver nanoparticles (AgNPs) are expected to enter the ecosystems where their toxicity in the environment is proposed. In this study, we exploited the effect of environmental anions on AgNP toxicity. AgNP were mixed with various environmental anions, and then exposed to Escherichia coli to determine the effect on bacteria growth inhibition. The results demonstrated that AgNP are not always toxic in the presence of sulfide, but can stimulate microbial growth at certain concentrations. Environmental chloride and phosphate anions cannot induce the stimulation because of their weak capacity to control the release of Ag + from AgNP. Ag + that released from AgNP is proven to be responsible for AgNP toxicity. Moreover, we found that AgNP toxicity is dependent on sulfuration rate. At the same sulfuration rate, AgNP shows an identical pattern of toxicity. This study indicates that only sulfide of the tested environmental anions can induce AgNP stimulation to microbial growth in a sulfuration rate dependent pattern and the toxicity originate from Ag + that released from AgNP. Copyright © 2016 Elsevier Ltd. All rights reserved.

A preliminary assessment of PM(10) and TSP concentrations in Tuticorin, India.

PubMed

Sivaramasundaram, K; Muthusubramanian, P

2010-06-01

The respirable particulate matter (RPM; PM(10)) and total suspended particulate matter (TSP) concentrations in ambient air in Tuticorin, India, were preliminarily estimated. Statistical analyses on so-generated database were performed to infer frequency distributions and to identify dominant meteorological factor affecting the pollution levels. Both the RPM and TSP levels were well below the permissible limits set by the US Environmental Protection Agency. As expected, lognormal distribution always fit the data during the study period. However, fit with the normal was also acceptable except for very few seasons. The RPM concentrations ranged between 20.9 and 198.2 mug/m(3), while the TSP concentrations varied from 51.5 to 333.3 mug/m(3) during the study period. There was a better correlation between PM(10-100) and TSP concentrations than that of PM(10) (RPM) and TSP concentrations, but the correlation of RPM fraction was also acceptable. It was found that wind speed was the most important meteorological factor affecting the concentrations of the pollutants of present interest. Significant seasonal variations in the pollutant concentrations of present interest were found at 5% significance level except for TSP concentrations in the year 2006.

Design of optimal groundwater remediation systems under flexible environmental-standard constraints.

PubMed

Fan, Xing; He, Li; Lu, Hong-Wei; Li, Jing

2015-01-01

In developing optimal groundwater remediation strategies, limited effort has been exerted to solve the uncertainty in environmental quality standards. When such uncertainty is not considered, either over optimistic or over pessimistic optimization strategies may be developed, probably leading to the formulation of rigid remediation strategies. This study advances a mathematical programming modeling approach for optimizing groundwater remediation design. This approach not only prevents the formulation of over optimistic and over pessimistic optimization strategies but also provides a satisfaction level that indicates the degree to which the environmental quality standard is satisfied. Therefore the approach may be expected to be significantly more acknowledged by the decision maker than those who do not consider standard uncertainty. The proposed approach is applied to a petroleum-contaminated site in western Canada. Results from the case study show that (1) the peak benzene concentrations can always satisfy the environmental standard under the optimal strategy, (2) the pumping rates of all wells decrease under a relaxed standard or long-term remediation approach, (3) the pumping rates are less affected by environmental quality constraints under short-term remediation, and (4) increased flexible environmental standards have a reduced effect on the optimal remediation strategy.

Environmental toxicology and risk assessment of pharmaceuticals from hospital wastewater.

PubMed

Escher, Beate I; Baumgartner, Rebekka; Koller, Mirjam; Treyer, Karin; Lienert, Judit; McArdell, Christa S

2011-01-01

In this paper, we evaluated the ecotoxicological potential of the 100 pharmaceuticals expected to occur in highest quantities in the wastewater of a general hospital and a psychiatric center in Switzerland. We related the toxicity data to predicted concentrations in different wastewater streams to assess the overall risk potential for different scenarios, including conventional biological pretreatment in the hospital and urine source separation. The concentrations in wastewater were estimated with pharmaceutical usage information provided by the hospitals and literature data on human excretion into feces and urine. Environmental concentrations in the effluents of the exposure scenarios were predicted by estimating dilution in sewers and with literature data on elimination during wastewater treatment. Effect assessment was performed using quantitative structure-activity relationships because experimental ecotoxicity data were only available for less than 20% of the 100 pharmaceuticals with expected highest loads. As many pharmaceuticals are acids or bases, a correction for the speciation was implemented in the toxicity prediction model. The lists of Top-100 pharmaceuticals were distinctly different between the two hospital types with only 37 pharmaceuticals overlapping in both datasets. 31 Pharmaceuticals in the general hospital and 42 pharmaceuticals in the psychiatric center had a risk quotient above 0.01 and thus contributed to the mixture risk quotient. However, together they constituted only 14% (hospital) and 30% (psychiatry) of the load of pharmaceuticals. Hence, medical consumption data alone are insufficient predictors of environmental risk. The risk quotients were dominated by amiodarone, ritonavir, clotrimazole, and diclofenac. Only diclofenac is well researched in ecotoxicology, while amiodarone, ritonavir, and clotrimazole have no or very limited experimental fate or toxicity data available. The presented computational analysis thus helps setting priorities for further testing. Separate treatment of hospital wastewater would reduce the pharmaceutical load of wastewater treatment plants, and the risk from the newly identified priority pharmaceuticals. However, because high-risk pharmaceuticals are excreted mainly with feces, urine source separation is not a viable option for reducing the risk potential from hospital wastewater, while a sorption step could be beneficial. Copyright © 2010 Elsevier Ltd. All rights reserved.

Morphology, spatial distribution, and concentration of flame retardants in consumer products and environmental dusts using scanning electron microscopy and Raman micro-spectroscopy.

PubMed

Wagner, Jeff; Ghosal, Sutapa; Whitehead, Todd; Metayer, Catherine

2013-09-01

We characterized flame retardant (FR) morphologies and spatial distributions in 7 consumer products and 7 environmental dusts to determine their implications for transfer mechanisms, human exposure, and the reproducibility of gas chromatography-mass spectrometry (GC-MS) dust measurements. We characterized individual particles using scanning electron microscopy/energy dispersive x-ray spectroscopy (SEM/EDS) and Raman micro-spectroscopy (RMS). Samples were screened for the presence of 3 FR constituents (bromine, phosphorous, non-salt chlorine) and 2 metal synergists (antimony and bismuth). Subsequent analyses of select samples by RMS enabled molecular identification of the FR compounds and matrix materials. The consumer products and dust samples possessed FR elemental weight percents of up to 36% and 31%, respectively. We identified 24 FR-containing particles in the dust samples and classified them into 9 types based on morphology and composition. We observed a broad range of morphologies for these FR-containing particles, suggesting FR transfer to dust via multiple mechanisms. We developed an equation to describe the heterogeneity of FR-containing particles in environmental dust samples. The number of individual FR-containing particles expected in a 1-mg dust sample with a FR concentration of 100ppm ranged from <1 to >1000 particles. The presence of rare, high-concentration bromine particles was correlated with decabromodiphenyl ether concentrations obtained via GC-MS. When FRs are distributed heterogeneously in highly concentrated dust particles, human exposure to FRs may be characterized by high transient exposures interspersed by periods of low exposure, and GC-MS FR concentrations may exhibit large variability in replicate subsamples. Current limitations of this SEM/EDS technique include potential false negatives for volatile and chlorinated FRs and greater quantitation uncertainty for brominated FR in aluminum-rich matrices. Copyright © 2013 Elsevier Ltd. All rights reserved.

Moss bags as sentinels for human safety in mercury-polluted groundwaters.

PubMed

Cesa, Mattia; Nimis, Pier Luigi; Buora, Clara; Lorenzonetto, Alberta; Pozzobon, Alessandro; Raris, Marina; Rosa, Maria; Salvadori, Michela

2014-05-01

An equation to estimate Hg concentrations of <4 μg/L in groundwaters of a polluted area in NE Italy was set out by using transplants of the aquatic moss Rhynchostegium riparioides as trace element bioaccumulators. The equation is derived from a previous mathematical model which was implemented under laboratory conditions. The work aimed at (1) checking the compliance of the uptake kinetics with the model, (2) improving/adapting the model for groundwater monitoring, (3) comparing the performances of two populations of moss collected from different sites, and (4) assessing the environmental impact of Hg contamination on a small river. The main factors affecting Hg uptake in the field were-as expected-water concentration and time of exposure, even though the uptake kinetics in the field were slightly different from those which were previously observed in the lab, since the redox environmental conditions influence the solubility of cationic Fe, which is a negative competitor of Hg(2+). The equation was improved by including the variable 'dissolved oxygen concentration'. A numerical parameter depending on the moss collection site was also provided, since the differences in uptake efficiency were observed between the two populations tested. Predicted Hg concentrations well fitted the values measured in situ (approximately ±50%), while a notable underestimation was observed when the equation was used to predict Hg concentration in a neighbouring river (-96%), probably due to the organic pollution which hampers metal uptake by mosses.

Metal pollution in Spanish terrestrial ecosystems during the twentieth century.

PubMed

Peñuelas, Josep; Filella, Iolanda

2002-01-01

We show here additional biological evidence of the alteration in global biogeochemistry by human activities during the twentieth century. The mineral concentration of herbarium specimens of 24 species of vascular plants and three species of bryophytes collected in North and East regions of Spain have substantially changed throughout the twentieth century. While V, a proxy tracer of oil pollution, exponentially increased in the last decades, other metals such as Cr, Ba, Sr, Al, Fe, Pb, Cd and Ti increased up to 1960-1970 and started to decrease in 1985-1995, when environmental legal regulations started to be effective. Multivariate principal component analysis showed an overall change in plant elemental concentrations throughout the different decades of the century and a clear separation of vascular plants and bryophytes. Likely important consequences for ecosystem structure and functioning and even for human health may be expected from these changes in mineral concentration.

Estimation of true serum thyroglobulin concentration using simultaneous measurement of serum antithyroglobulin antibody.

PubMed

Ahn, Byeong-Cheol; Lee, Won Kee; Jeong, Shin Young; Lee, Sang-Woo; Lee, Jaetae

2013-01-01

We investigated the analytical interference of antithyroglobulin antibody (TgAb) to thyroglobulin (Tg) measurement and tried to convert measured Tg concentration to true Tg concentration using a mathematical equation which includes a concentration of TgAb. Methods. Tg was measured by immunoradiometric assay and TgAb by radioimmunoassy. Experimental samples were produced by mixing Tg and TgAb standard solutions or mixing patients' serum with high Tg or high TgAb. Mathematical equations for prediction of expected Tg concentration with measured Tg and TgAb concentrations were deduced. The Tg concentration calculated using the equations was compared with the expected Tg concentration. Results. Measured Tg concentrations of samples having high TgAb were significantly lower than their expected Tg concentration. Magnitude of TgAb interference with the Tg assay showed a positive correlation with concentration of TgAb. Mathematical equations for estimation of expected Tg concentration using measured Tg and TgAb concentrations were successfully deduced and the calculated Tg concentration showed excellent correlation with expected Tg concentration. Conclusions. A mathematic equation for estimation of true Tg concentration using measured Tg and TgAb concentration was deduced. Tg concentration calculated by use of the equation might be more valuable than measured Tg concentration in patients with differentiated thyroid cancer.

In vitro gastrointestinal mimetic protocol for measuring bioavailable contaminants

DOEpatents

Holman, Hoi-Ying N.

2000-01-01

The present invention relates to measurements of contaminants in the soil and other organic or environmental materials, using a biologically relevant chemical analysis that will measure the amount of contaminants in a given sample that may be expected to be absorbed by a human being ingesting the contaminated soil. According to the present invention, environmental samples to be tested are added to a pre-prepared physiological composition of bile salts and lipids. They are thoroughly mixed and then the resulting mixture is separated e.g. by centrifugation. The supernatant is then analyzed for the presence of contaminants and these concentrations are compared to the level of contaminants in the untreated samples. It is important that the bile salts and lipids be thoroughly pre-mixed to form micelles.

ARM Evaluation Product : Droplet Number Concentration Value-Added Product

DOE Data Explorer

Riihimaki, Laura

2014-05-15

Cloud droplet number concentration is an important factor in understanding aerosol-cloud interactions. As aerosol concentration increases, it is expected that droplet number concentration, Nd, will increase and droplet size decrease, for a given liquid water path (Twomey 1977), which will greatly affect cloud albedo as smaller droplets reflect more shortwave radiation. However, the magnitude and variability of these processes under different environmental conditions is still uncertain. McComiskey et al. (2009) have implemented a method, based on Boers and Mitchell (1994), for calculating Nd from ground-based remote sensing measurements of optical depth and liquid water path. They show that the magnitude of the aerosol-cloud interactions (ACI) varies with a range of factors, including the relative value of the cloud liquid water path (LWP), the aerosol size distribution, and the cloud updraft velocity. Estimates of Nd under a range of cloud types and conditions and at a variety of sites are needed to further quantify the impacts of aerosol cloud interactions.

75 FR 38768 - Ashley National Forest, UT, High Uintas Wilderness-Colorado River Cutthroat Trout Habitat...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-06

... to prepare an environmental impact statement. SUMMARY: The Ashley National Forest in cooperation with... analysis must be received by August 5, 2010. The draft environmental impact statement is expected February 2011 and the final environmental impact statement is expected June 2011. ADDRESSES: Send written...

Benthic foraminifera as indicators of pollution in high latitude marine environments

NASA Astrophysics Data System (ADS)

Dijkstra, N.; Junttila, J.; Husum, K.; Carroll, J.; Klitgaard-Kristensen, D.; Hald, M.

2012-04-01

An increasing number of studies demonstrate the potential of benthic foraminifera to characterize ecological status. However, the use of benthic foraminifera as bio-indicators has previously not been tested in high latitudes. This research contributes to the development of foraminifera as a bio-monitoring technique for the Arctic region, as industrial activities in this region will increase in the coming years. Surface sediments (0-1 cm) from sites close to gas fields in the SW Barents Sea were studied. In addition, to elucidate the range from less to very affected, surface sediments from the harbor of the town of Hammerfest (70° N) were studied. At least 300 living benthic foraminifera from the size fraction 100 µm-1 mm were counted and identified at species level. Pollution levels (heavy metals and persistent organic pollutants) and sediment properties (grainsize and TOC) were also analyzed. Pollution levels at the sea floor in the SW Barents Sea are of background to good level (level I-II) according to the definitions by the Water Framework Directorate (WFD). Benthic foraminiferal assemblages are influenced by natural environmental parameters such as water mass properties, water depth, nutrient availability, bottom current strength, and grain size. Surface sediments from the Hammerfest harbor are of moderate environmental status (WFD level II-III) based on heavy metal concentrations and of bad environmental status (WFD IV-V) based on persistent organic pollutant concentrations. Opportunistic benthic foraminifera are dominating the assemblages. The most polluted areas in the harbor are barren for foraminifera or have high amounts of deformed shells. In both environments the foraminiferal diversity of the samples, does not correspond to expected environmental status based on the pollution levels of the sediments. Environmental status classes, based on benthic foraminifera instead of macrofauna, would allow rapid analyses of the environmental impact of pollution.

Developing and applying metamodels of high resolution ...

EPA Pesticide Factsheets

As defined by Wikipedia (https://en.wikipedia.org/wiki/Metamodeling), “(a) metamodel or surrogate model is a model of a model, and metamodeling is the process of generating such metamodels.” The goals of metamodeling include, but are not limited to (1) developing functional or statistical relationships between a model’s input and output variables for model analysis, interpretation, or information consumption by users’ clients; (2) quantifying a model’s sensitivity to alternative or uncertain forcing functions, initial conditions, or parameters; and (3) characterizing the model’s response or state space. Using five existing models developed by US Environmental Protection Agency, we generate a metamodeling database of the expected environmental and biological concentrations of 644 organic chemicals released into nine US rivers from wastewater treatment works (WTWs) assuming multiple loading rates and sizes of populations serviced. The chemicals of interest have log n-octanol/water partition coefficients ( ) ranging from 3 to 14, and the rivers of concern have mean annual discharges ranging from 1.09 to 3240 m3/s. Log linear regression models are derived to predict mean annual dissolved and total water concentrations and total sediment concentrations of chemicals of concern based on their , Henry’s Law Constant, and WTW loading rate and on the mean annual discharges of the receiving rivers. Metamodels are also derived to predict mean annual chemical

Population growth and consumption.

PubMed

Chalkley, K

1997-04-01

The relationship between population growth, resource consumption, and environmental degradation is complex. The rise in "greenhouse gases" that will cause climatic change is clearly due to human activity, and pollutants are often concentrated in densely populated areas. However, even an area with a negative population growth, such as Russia, can experience severe environmental degradation due to poor management. Consumption patterns have the most effect on ozone depletion, while population growth threatens biodiversity of and within species through the destruction of ecosystems. Migration joins population growth and social factors, such as land inequality, as major causes of deforestation, and global demand for water is expected to increase faster than the rate of population growth. Coastal development and over-fishing threaten to deplete the oceans, while soil quality is threatened by inappropriate land use. Estimates of the earth's carrying capacity range from less than 3 billion to more than 44 billion people, indicating how difficult it is to assess this figure. Development efforts throughout the world may lead to human gains that will ultimately be negated by environmental losses. These factors have led to growing support for environmentally sustainable development.

Analytical and environmental aspects of the flame retardant tetrabromobisphenol-A and its derivatives.

PubMed

Covaci, Adrian; Voorspoels, Stefan; Abdallah, Mohamed Abou-Elwafa; Geens, Tinne; Harrad, Stuart; Law, Robin J

2009-01-16

The present article reviews the available literature on the analytical and environmental aspects of tetrabromobisphenol-A (TBBP-A), a currently intensively used brominated flame retardant (BFR). Analytical methods, including sample preparation, chromatographic separation, detection techniques, and quality control are discussed. An important recent development in the analysis of TBBP-A is the growing tendency for liquid chromatographic techniques. At the detection stage, mass-spectrometry is a well-established and reliable technology in the identification and quantification of TBBP-A. Although interlaboratory exercises for BFRs have grown in popularity in the last 10 years, only a few participating laboratories report concentrations for TBBP-A. Environmental levels of TBBP-A in abiotic and biotic matrices are low, probably due to the major use of TBBP-A as reactive FR. As a consequence, the expected human exposure is low. This is in agreement with the EU risk assessment that concluded that there is no risk for humans concerning TBBP-A exposure. Much less analytical and environmental information exists for the various groups of TBBP-A derivatives which are largely used as additive flame retardants.

Impacts of oak pollen on allergic asthma in the United States ...

EPA Pesticide Factsheets

Oak pollen season length for moderate (RCP4.5) and severe climate change scenarios (RCP8.5) are estimated through 2090 using five climate models and published relationships between temperature, precipitation, and oak pollen season length. We calculated asthma ED visit counts associated with 1994-2010 average oak pollen concentrations and simulated future oak pollen season length changes using the Environmental Benefits Mapping and Analysis Program (BenMAP-CE), driven by epidemiologically-derived concentration-response relationships. Future climate change is expected to lengthen and intensify pollen seasons in the U.S., potentially increasing incidence of allergic asthma. We developed a proof-of-concept approach for estimating asthma emergency department (ED) visits in the U.S. associated with present-day and climate-induced changes in oak pollen.

Perchlorate as an environmental contaminant.

PubMed

Urbansky, Edward Todd

2002-01-01

Perchlorate anion (ClO4-) has been found in drinking water supplies throughout the southwestern United States. It is primarily associated with releases of ammonium perchlorate by defense contractors, military operations, and aerospace programs. Ammonium perchlorate is used as a solid oxidant in missile and rocket propulsion systems. Traces of perchlorate are found in Chile saltpeter, but the use of such fertilizer has not been associated with large scale contamination. Although it is a strong oxidant, perchlorate anion is very persistent in the environment due to the high activation energy associated with its reduction. At high enough concentrations, perchlorate can affect thyroid gland functions, where it is mistakenly taken up in place of iodide. A safe daily exposure has not yet been set, but is expected to be released in 2002. Perchlorate is measured in environmental samples primarily by ion chromatography. It can be removed by anion exchange or membrane filtration. It is destroyed by some biological and chemical processes. The environmental occurrence, toxicity, analytical chemistry, and remediative approaches are discussed.

Nanoparticle Exposure and Hormetic Dose–Responses: An Update

PubMed Central

Leso, Veruscka; Fontana, Luca; Calabrese, Edward J.

2018-01-01

The concept of hormesis, as an adaptive response of biological systems to moderate environmental challenges, has raised considerable nano-toxicological interests in view of the rapid pace of production and application of even more innovative nanomaterials and the expected increasing likelihood of environmental and human exposure to low-dose concentrations. Therefore, the aim of this review is to provide an update of the current knowledge concerning the biphasic dose–responses induced by nanoparticle exposure. The evidence presented confirmed and extended our previous findings, showing that hormesis is a generalized adaptive response which may be further generalized to nanoscale xenobiotic challenges. Nanoparticle physico-chemical properties emerged as possible features affecting biphasic relationships, although the molecular mechanisms underlining such influences remain to be fully understood, especially in experimental settings resembling long-term and low-dose realistic environmental exposure scenarios. Further investigation is necessary to achieve helpful information for a suitable assessment of nanomaterial risks at the low-dose range for both the ecosystem function and the human health. PMID:29534471

Environmental health training: a survey of family practice residency program directors.

PubMed

Musham, C; Bellack, J P; Graber, D R; Holmes, D

1996-01-01

The Institute of Medicine and the American College of Physicians have advocated that physicians broaden their participation in the environmental aspects of medical care. Accordingly, both organizations recommend training of future primary care physicians for greater competency in and appreciation of this area of medicine. This study assessed the present emphasis on environmental health in family practice residency programs by examining the extent program directors expect graduates to have specific competencies in environmental medicine. A written survey was mailed to directors of all 393 family practice residency programs listed in the 1993 Directory of Family Practice Residency Programs. Respondents were asked to indicate the extent to which each of eight environmental health competencies was expected of their graduates. The list of environmental health competencies was based on the literature and on interviews with family practice educators. Perceptions about the "present" and "ideal" environmental health emphasis in their programs were also measured. A total of 262 completed surveys were returned for a response rate of 67%. Respondents reported that they expected their graduates to have general knowledge of and competence in environmental health areas that pertain to patient care. Competencies with social and political implications were least likely to be expected. Two thirds of respondents indicated that "minimal emphasis" is presently placed on environmental health. Seventy percent indicated that the "ideal" amount of emphasis placed on this topic is "moderate." This survey's results suggest that family practice residency program directors expect their graduates to know basic environmental health concepts and be skilled in related aspects of patient care. The development of environmental health training programs must take into account that environmental health may be viewed as a topic of secondary importance and that in most residencies, faculty expertise in this area is limited. For this reason, a self-tutoring strategy, aimed toward the educational needs of both faculty and residents, is recommended.

Chemodetection in fluctuating environments: receptor coupling, buffering, and antagonism.

PubMed

Lalanne, Jean-Benoît; François, Paul

2015-02-10

Variability in the chemical composition of the extracellular environment can significantly degrade the ability of cells to detect rare cognate ligands. Using concepts from statistical detection theory, we formalize the generic problem of detection of small concentrations of ligands in a fluctuating background of biochemically similar ligands binding to the same receptors. We discover that in contrast with expectations arising from considerations of signal amplification, inhibitory interactions between receptors can improve detection performance in the presence of substantial environmental variability, providing an adaptive interpretation to the phenomenon of ligand antagonism. Our results suggest that the structure of signaling pathways responsible for chemodetection in fluctuating and heterogeneous environments might be optimized with respect to the statistics and dynamics of environmental composition. The developed formalism stresses the importance of characterizing nonspecific interactions to understand function in signaling pathways.

Strategies for communicating quality expectations for environmental service contracts : final report.

DOT National Transportation Integrated Search

2017-03-01

This study explores the communication of quality expectations between the Office of Environment Services (OES) and environmental consulting firms contributing to the Plan Development Process of the Georgia Department of Transportation (GDOT). The ove...

Sewage contamination in the upper Mississippi River as measured by the fecal sterol, coprostanol

USGS Publications Warehouse

Writer, J.H.; Leenheer, J.A.; Barber, L.B.; Amy, G.L.; Chapra, S.C.

1995-01-01

The molecular sewage indicator, coprostanol, was measured in bed sediments of the Mississippi River for the purpose of determining sewage contamination. Coprostanol is a non-ionic, non-polar, organic molecule that associates with sediments in surface waters, and concentrations of coprostanol in bed sediments provide an indication of long-term sewage loads. Because coprostanol concentrations are dependent on particle size and percent organic carbon, a ratio between coprostanol (sewage sources) and cholestanol + cholesterol (sewage and non-sewage sources) was used to remove the biases related to particle size and percent organic carbon. The dynamics of contaminant transport in the Upper Mississippi River are influenced by both hydrologic and geochemical parameters. A mass balance model incorporating environmental parameters such as river and tributary discharge, suspended sediment concentration, fraction of organic carbon, sedimentation rates, municipal discharges and coprostanol decay rates was developed that describes coprostanol concentrations and therefore, expected patterns of municipal sewage effects on the Upper Mississippi River. Comparison of the computed and the measured coprostanol concentrations provides insight into the complex hydrologic and geochemical processes of contaminant transport and the ability to link measured chemical concentrations with hydrologic characteristics of the Mississippi River.

Temporal trends in mercury concentrations in raptor flight feathers stored in an environmental specimen bank in Galicia (NW Spain) between 2000 and 2013.

PubMed

García-Seoane, Rita; Varela, Zulema; Carballeira, Alejo; Aboal, Jesús R; Fernández, J Ángel

2017-03-01

Temporal trends in Hg concentrations were investigated in primary flight feathers from 319 specimens of three birds of prey: P7 in the northern goshawk (Accipiter gentilis), P6 in the common buzzard (Buteo buteo) and P5 in the tawny owl (Strix aluco). The samples were stored in a regional environmental specimen bank and belonged to specimens which died between 2000 and 2013 in Galicia (NW Spain). We would expect to see a decline in Hg concentrations across the study period, as data of atmospheric emissions show a gradual reduction of this pollutant in Europe in the last two decades. The study did not reveal any temporal pattern in Hg concentrations of feathers in any of the three species for the study period, may be due to the persistence of Hg in the environment, but showed a low level of contamination by this metal in the study area. In addition, the results show high intra-specific, as well as, inter-annual and inter-specific variability in data, mainly attributed to the level of exposure of the raptors to this pollutant and to the biomagnification process of Hg through food chains. These findings indicate that the high variability can be a limiting factor in the use of raptors for biomonitoring temporal patterns of Hg, but nevertheless, the technique provides qualitative information about the amount of Hg that reach the top of the terrestrial food chains.

Country report: Broiler industry and broiler litter-related problems in the southeastern United States.

PubMed

Paudel, Krishna P; McIntosh, Christopher S

2005-01-01

This report describes the development of the broiler litter problem in the southeastern United States, including the economic opportunity and environmental challenges brought to the region by the industry. Through an analysis applied to the State of Georgia, land application of litter as a disposal alternative is examined along with its associated benefits. The analysis indicates that litter could be transported economically up to 256 km for cropland application. Excessive broiler litter production in a few concentrated regions is expected to stimulate the development of alternative approaches to broiler litter management, such as electricity generation.

Heavy metal concentrations and toxicity in water and sediment from stormwater ponds and sedimentation tanks.

PubMed

Karlsson, Kristin; Viklander, Maria; Scholes, Lian; Revitt, Mike

2010-06-15

Sedimentation is a widely used technique in structural best management practices to remove pollutants from stormwater. However, concerns have been expressed about the environmental impacts that may be exerted by the trapped pollutants. This study has concentrated on stormwater ponds and sedimentation tanks and reports on the accumulated metal concentrations (Cd, Cr, Ni, Pb, and Zn) and the associated toxicity to the bacteria Vibrio fischeri. The metal concentrations are compared with guidelines and the toxicity results are assessed in relation to samples for which metal concentrations either exceed or conform to these values. The water phase metal concentrations were highest in the ponds whereas the sedimentation tanks exhibited a distinct decrease towards the outlet. However, none of the water samples demonstrated toxicity even though the concentrations of Cu, Pb, and Zn exceeded the threshold values for the compared guidelines. The facilities with higher traffic intensities had elevated sediment concentrations of Cr, Cu, Ni, and Zn which increased towards the outlet for the sedimentation tanks in agreement with the highest percentage of fine particles. The sediments in both treatment facilities exhibited the expected toxic responses in line with their affinity for heavy metals but the role of organic carbon content is highlighted. Copyright 2010 Elsevier B.V. All rights reserved.

CHEMICAL DIFFERENCES BETWEEN SLUDGE SOLIDS AT THE F AND H AREA TANK FARMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reboul, S.

2012-08-29

The primary source of waste solids received into the F Area Tank Farm (FTF) was from PUREX processing performed to recover uranium and plutonium from irradiated depleted uranium targets. In contrast, two primary sources of waste solids were received into the H Area Tank Farm (HTF): a) waste from PUREX processing; and b) waste from H-modified (HM) processing performed to recover uranium and neptunium from burned enriched uranium fuel. Due to the differences between the irradiated depleted uranium targets and the burned enriched uranium fuel, the average compositions of the F and H Area wastes are markedly different from onemore » another. Both F and H Area wastes contain significant amounts of iron and aluminum compounds. However, because the iron content of PUREX waste is higher than that of HM waste, and the aluminum content of PUREX waste is lower than that of HM waste, the iron to aluminum ratios of typical FTF waste solids are appreciably higher than those of typical HTF waste solids. Other constituents present at significantly higher concentrations in the typical FTF waste solids include uranium, nickel, ruthenium, zinc, silver, cobalt and copper. In contrast, constituents present at significantly higher concentrations in the typical HTF waste solids include mercury, thorium, oxalate, and radionuclides U-233, U-234, U-235, U-236, Pu-238, Pu-242, Cm-244, and Cm-245. Because of the higher concentrations of Pu-238 in HTF, the long-term concentrations of Th-230 and Ra-226 (from Pu-238 decay) will also be higher in HTF. The uranium and plutonium distributions of the average FTF waste were found to be consistent with depleted uranium and weapons grade plutonium, respectively (U-235 comprised 0.3 wt% of the FTF uranium, and Pu-240 comprised 6 wt% of the FTF plutonium). In contrast, at HTF, U-235 comprised 5 wt% of the uranium, and Pu-240 comprised 17 wt% of the plutonium, consistent with enriched uranium and high burn-up plutonium. X-ray diffraction analyses of various FTF and HTF samples indicated that the primary crystalline compounds of iron in sludge solids are Fe{sub 2}O{sub 3}, Fe{sub 3}O{sub 4}, and FeO(OH), and the primary crystalline compounds of aluminum are Al(OH){sub 3} and AlO(OH). Also identified were carbonate compounds of calcium, magnesium, and sodium; a nitrated sodium aluminosilicate; and various uranium compounds. Consistent with expectations, oxalate compounds were identified in solids associated with oxalic acid cleaning operations. The most likely oxidation states and chemical forms of technetium are assessed in the context of solubility, since technetium-99 is a key risk driver from an environmental fate and transport perspective. The primary oxidation state of technetium in SRS sludge solids is expected to be Tc(IV). In salt waste, the primary oxidation state is expected to be Tc(VII). The primary form of technetium in sludge is expected to be a hydrated technetium dioxide, TcO{sub 2} {center_dot} xH{sub 2}O, which is relatively insoluble and likely co-precipitated with iron. In salt waste solutions, the primary form of technetium is expected to be the very soluble pertechnetate anion, TcO{sub 4}{sup -}. The relative differences between the F and H Tank Farm waste provide a basis for anticipating differences that will occur as constituents of FTF and HTF waste residue enter the environment over the long-term future. If a constituent is significantly more dominant in one of the Tank Farms, its long-term environmental contribution will likely be commensurately higher, assuming the environmental transport conditions of the two Tank Farms share some commonality. It is in this vein that the information cited in this document is provided - for use during the generation, assessment, and validation of Performance Assessment modeling results.« less

Whale baleen trace element signatures: a predictor of environmental life history?

NASA Astrophysics Data System (ADS)

Wilcox Freeburg, E.; Brault, S.; Mayo, C.; Oktay, S.; Hannigan, R.

2009-12-01

The analysis of trace element composition of biogenic structures (e.g., otoliths, feathers) by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) provides unique insights into the environmental life history of individuals. We studied the trace element chemistry of right whale baleens in an attempt to reconstruct migration patterns. Though much is known about the feeding and breeding habitats of these whales, little is known about the location in which they spend most of their adult years. Baleens, made of keratin, grow continuously and are metabolically inactive. Previous work showed that the stable isotope chemistry along the length of a baleen records changes in diet, such as weaning. Baleen chemistry should, therefore, also record the environmental life history of the individual. Trace metal chemistry along a single baleen plate from a right whale were analyzed by LA-ICP-MS. Semi-quantitative elemental signatures were obtained using NIST 612 (glass standard) and MACS-3 (calcium carbonate standard). These concentrations were then compared for accuracy to acid digested baleen laterally adjacent to the laser ablation site via aqueous ICP-MS. Elemental chemistry was compared to known feeding/breeding locations of the individual (water chemistry). Using these comparisons as well as principal components analysis, life history of the individual was reconstructed. Development of an in-house keratin standard is in progress and is expected to strengthen the confidence in results. Future work is expected to bring a more complete knowledge of right whale wintering habits.

Characteristics and environmental fate of the anionic surfactant sodium lauryl ether sulphate (SLES) used as the main component in foaming agents for mechanized tunnelling.

PubMed

Barra Caracciolo, Anna; Cardoni, Martina; Pescatore, Tanita; Patrolecco, Luisa

2017-07-01

The anionic surfactant sodium lauryl ether sulphate (SLES) is the main component of most commercial products used for soil conditioning in the excavation industry, in particular as lubricants for mechanized tunnelling. Its use during the excavation processes can result in either the subsequent possible re-use of the huge amount of soil debris as by-products (e.g. land covering) or its discharge as waste. Currently, there are neither SLES soil threshold limits in European legislation, nor comprehensive studies on the environmental risk for soil ecosystems in these exposure scenarios. In this context, the present paper reviews the available data on the intrinsic characteristics of persistence and the ecotoxicological effects of the anionic surfactant SLES. Although SLES is generally reported to be biodegradable in standard tests, with degradation rates between 7 h and 30 days, depending on the initial conditions, data on its biodegradation in environmental studies are quite scarce. Consequently, assessing SLES biodegradation rates in field conditions is crucial for evaluating if in residual concentrations (typically in the range 40-500 mg/kg in excavated soils) it can or not be a potential hazard for terrestrial and water organisms. Laboratory ecotoxicological tests pointed out detrimental effects of SLES for aquatic organisms, while data on the terrestrial species are rather poor so far and further studies at the expected environmental concentrations are necessary. Finally, the review reports the main analytical methods available for detecting anionic surfactants in solid matrices and the future research needed to improve knowledge on the possible environmental risks posed by the use of SLES in foaming agents for mechanized tunnelling. Copyright © 2017 Elsevier Ltd. All rights reserved.

Impacts of iron and steelmaking facilities on soil quality.

PubMed

Strezov, Vladimir; Chaudhary, Chandrakant

2017-12-01

Iron and steel are highly important materials used in a wide range of products with important contribution to the economic development. The processes for making iron and steel are energy intensive and known to contribute to local pollution. Deposition of the metals may also have adverse impacts on soil quality, which requires detailed assessment. The aim of this study was to investigate the impacts of iron and steelmaking facilities on the local soil quality. Soil samples were collected in the vicinity of two steelmaking sites in Australia, one based on blast furnace steelmaking operation, while the second site was based on electric arc furnace steel recycling. The soil samples were compared to a background site where no industrial impact is expected. The soil collected near industrial facilities contained larger toxic metal contents, however this concentration for all priority metals was within the Australian National Environmental Protection Measure guidelines for the acceptable recreational soil quality. When compared to the international soil quality guidelines, some of the soils collected near the industrial sites, particularly near the blast furnace operated steelmaking, exceeded the arsenic, iron and manganese (according to United States Environmental Protection Agency guidelines) and chromium, copper and nickel concentrations (according to the Canadian guidelines). The work further provided a novel environmental assessment model taking into consideration the environmental and health impacts of each element. The environmental assessment revealed most significant contribution of manganese, followed by titanium, zinc, chromium and lead. Titanium was the second most important contributor to the soil quality, however this metal is currently not included in any of the international soil quality guidelines. Copyright © 2017 Elsevier Ltd. All rights reserved.

Space Transportation System Thermal Environmental Flux Reference Book

NASA Technical Reports Server (NTRS)

1979-01-01

The information necessary to estimate the thermal environment in which proposed instruments will be expected to operate is presented in curves and tables which indicate the magnitude of the environmental fluxes which can be expected for various space transportation system missions.

Fate and risks of nanomaterials in aquatic and terrestrial environments.

PubMed

Batley, Graeme E; Kirby, Jason K; McLaughlin, Michael J

2013-03-19

Over the last decade, nanoparticles have been used more frequently in industrial applications and in consumer and medical products, and these applications of nanoparticles will likely continue to increase. Concerns about the environmental fate and effects of these materials have stimulated studies to predict environmental concentrations in air, water, and soils and to determine threshold concentrations for their ecotoxicological effects on aquatic or terrestrial biota. Nanoparticles can be added to soils directly in fertilizers orplant protection products or indirectly through application to land or wastewater treatment products such as sludges or biosolids. Nanoparticles may enter aquatic systems directly through industrial discharges or from disposal of wastewater treatment effluents or indirectly through surface runoff from soils. Researchers have used laboratory experiments to begin to understand the effects of nanoparticles on waters and soils, and this Account reviews that research and the translation of those results to natural conditions. In the environment, nanoparticles can undergo a number of potential transformations that depend on the properties both of the nanoparticle and of the receiving medium. These transformations largely involve chemical and physical processes, but they can involve biodegradation of surface coatings used to stabilize many nanomaterial formulations. The toxicity of nanomaterials to algae involves adsorption to cell surfaces and disruption to membrane transport. Higher organisms can directly ingest nanoparticles, and within the food web, both aquatic and terrestrial organisms can accumulate nanoparticles. The dissolution of nanoparticles may release potentially toxic components into the environment. Aggregation with other nanoparticles (homoaggregation) or with natural mineral and organic colloids (heteroaggregation) will dramatically change their fate and potential toxicity in the environment. Soluble natural organic matter may interact with nanoparticles to change surface charge and mobility and affect the interactions of those nanoparticles with biota. Ultimately, aquatic nanomaterials accumulate in bottom sediments, facilitated in natural systems by heteroaggregation. Homoaggregates of nanoparticles sediment more slowly. Nanomaterials from urban, medical, and industrial sources may undergo significant transformations during wastewater treatment processes. For example, sulfidation of silver nanoparticles in wastewater treatment systems converts most of the nanoparticles to silver sulfides (Ag₂S). Aggregation of the nanomaterials with other mineral and organic components of the wastewater often results in most of the nanomaterial being associated with other solids rather than remaining as dispersed nanosized suspensions. Risk assessments for nanomaterial releases to the environment are still in their infancy, and reliable measurements of nanomaterials at environmental concentrations remain challenging. Predicted environmental concentrations based on current usage are low but are expected to increase as use increases. At this early stage, comparisons of estimated exposure data with known toxicity data indicate that the predicted environmental concentrations are orders of magnitude below those known to have environmental effects on biota. As more toxicity data are generated under environmentally-relevant conditions, risk assessments for nanomaterials will improve to produce accurate assessments that assure environmental safety.

The occurrence and ecological risk assessment of phthalate esters (PAEs) in urban aquatic environments of China.

PubMed

Zhang, Lulu; Liu, Jingling; Liu, Huayong; Wan, Guisheng; Zhang, Shaowei

2015-07-01

Phthalate esters (PAEs) are widely used in the manufacturing of plastics, and the demand for PAEs has grown rapidly, especially in China. This trend will lead to much more environmental PAE contamination. PAEs are listed as priority substances in the European Union and are therefore subject to ecological risk assessments. This paper reviews the literature concerning the pollution status of PAEs and their ecological risk to aquatic environments. Risk quotients (RQs) based on the predicted no effect concentration and PAE concentrations in aquatic environments demonstrated significant (10 ≤ RQ < 100) or expected (RQ ≥ 100) potential adverse effects for algae, Daphnia, and fish in aquatic environments near PAE-based industrial and urban areas. Thus, the ecological risk of PAEs in Chinese aquatic environments should be considered, especially in areas where commercial plastics are produced.

Mending the Med.

PubMed

Batisse, M

1994-01-01

In 1975, the Barcelona Convention to Protect the Sea was signed with an action plan to deal with marine pollution and halting land-based contributions to water pollution. Specifically, the Blue Plan aimed to attack the interaction between population, natural resources, environmental degradation, and economic development for the entire Mediterranean region. Scenarios were constructed to depict demographic, international economic, and national development prospects. Population was expected to grow from 357 million in 1985 to 575 million in 2025. Population concentration was expected to decline from 66% in the north to 22% in 2025. The populations in the south and east would grow to 5 times the 1950 figures. Fertility rates are expected to fall in the south, as educational levels of women rise. The decline in population in the north will mean an aging population in the north and a young population in the south with employment imbalances. Rapid urbanization will be a problem throughout the region, and particularly in the coastal areas. The demand for water, waste disposal, and conflicting pressures on use of sea and land will be the consequences. Tourism will aggravate general population conditions. The coastal regions currently receive about 100 million international and domestic tourists annually. Under poor economic conditions, scenarios would project tourism increases to 170 million by 2025. Under sustainable development scenarios, the numbers would increase even higher to 340 million tourists, mostly domestic. The environmental impact of tourism centers on the pressure on water resources, space use, and solid and liquid waste, during the summer when the water supply is low and the forests are dry. Most countries rely heavily on tourism for balance of payments and as a source of hard currency for food imports. The expectation is that the coastal areas, though fragile, are the primary asset for Mediterranean countries. Coast management thus far has contributed to erosion, deforestation, and erratic concrete surfacing of shore areas. Delays in sustainable development will only contribute to further pollution. The entire Mediterranean region could face social and ecological disruption in the future if population development needs are not met. Environmental and development issues threaten long-term peace and stability.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chitra Sivaraman, PNNL

Cloud droplet number concentration is an important factor in understanding aerosol-cloud interactions. As aerosol concentration increases, it is expected that droplet number concentration (Nd) will increase and droplet size will decrease, for a given liquid water path. This will greatly affect cloud albedo as smaller droplets reflect more shortwave radiation; however, the magnitude and variability of these processes under different environmental conditions is still uncertain.McComiskey et al. (2009) have implemented a method, based onBoers and Mitchell (1994), for calculating Nd from ground-based remote sensing measurements of optical depth and liquid water path. They show that the magnitude of the aerosol-cloudmore » interactions (ACI) varies with a range of factors, including the relative value of the cloud liquid water path (LWP), the aerosol size distribution, and the cloud updraft velocity. Estimates of Nd under a range of cloud types and conditions and at a variety of sites are needed to further quantify the impacts of aerosol cloud interactions. In order to provide data sets for studying aerosol-cloud interactions, the McComiskey et al. (2009) method was implemented as the Droplet Number Concentration (NDROP) value-added product (VAP).« less

Prenatal exposure of Canadian children to polychlorinated biphenyls and mercury.

PubMed

Muckle, G; Dewailly, E; Ayotte, P

1998-01-01

This article documents the exposure to environmental contaminants within sub-groups of the Canadian population who are considered to be at risk as a result of the food they eat. We measured the concentrations of polychlorinated biphenyls (PCBs) and mercury in the blood drawn from the umbilical cords of newborns in various Aboriginal communities, in a coastal community and in the general population. Average concentrations of Aroclor 1260 ranged between 0.3 and 2.0 micrograms/L and were clearly highest among the Inuit of Nunavik and Baffin Island and among the Montagnais of Quebec. In these groups, we found contaminant levels in the blood of newborns that exceed the threshold beyond which cognitive impairments are expected to result. Average concentrations of mercury ranged between 1.0 and 14.2 micrograms/L; the Inuit of Nunavik and the NWT exhibited the highest exposure levels. A portion of the Nunavik and NWT Inuit had concentrations beyond the critical threshold for the appearance of neurological consequences. The variations in exposure levels resulted from the different nutritional practices of these Canadian sub-groups.

The history of hexachlorobenzene accumulation in Svalbard fjords.

PubMed

Pouch, A; Zaborska, A; Pazdro, K

2018-05-24

In the present study, we investigated the spatial and historical trends of hexachlorobenzene (HCB) contamination in dated sediments of three Svalbard fjords (Kongsfjorden, Hornsund, Adventfjorden) differing in environmental conditions and human impact. HCB concentrations ranging from below limit of quantification (6.86 pg/g d.w.) to 143.99 pg/g d.w. were measured. The highest concentrations were measured in two surface sediment layers of the core collected in Hornsund near the melting glacier. The lowest concentrations of HCB were measured in Adventfjorden, suggesting that local source of HCB is not significant and global transport processes are the major transport pathways. The history of HCB deposition did not fully reflect the history of HCB emission (largest in 1950s and 1960s). In case of several sediment cores, the HCB enrichment in surface (recent) sediments was noticed. This can indicate importance of secondary sources of HCB, e.g., the influx of HCB accumulated over decades on the surface of glaciers. Detected levels of HCB were generally low and did not exceed background concentration levels; thus, a negative effect on benthic organisms is not expected.

Innate resistance to sporicides and potential failure to decontaminate.

PubMed

Maillard, J-Y

2011-03-01

Bacterial spores are frequently intrinsically resistant to biocides and only a number of alkylating and oxidising biocides are sporicidal under certain conditions. Activity against spores is affected by several key factors such as concentration, exposure time, soiling, and the types of surface to be treated. Sporicidal efficacy is usually achieved after an exposure time of several minutes with a high concentration of a biocide. Failure to understand these factors will result in decreased sporicide activity and spore survival. Sporicides in healthcare settings are used for surface disinfection and for the high level disinfection of certain medical devices (e.g. endoscopes). With efficacy data in mind, sporicidal activity should be achieved for the disinfection of medical devices where both high concentration and long exposure time occur. However, for the disinfection of environmental surfaces, high concentration is not recommended, nor is long exposure time achievable. In this case, sporicidal activity is severely reduced and spore survival following treatment is to be expected and contributes to the explanation of spore persistence on surfaces. Copyright © 2010 The Hospital Infection Society. Published by Elsevier Ltd. All rights reserved.

Environmental safety to decomposer invertebrates of azadirachtin (neem) as a systemic insecticide in trees to control emerald ash borer.

PubMed

Kreutzweiser, David; Thompson, Dean; Grimalt, Susana; Chartrand, Derek; Good, Kevin; Scarr, Taylor

2011-09-01

The non-target effects of an azadirachtin-based systemic insecticide used for control of wood-boring insect pests in trees were assessed on litter-dwelling earthworms, leaf-shredding aquatic insects, and microbial communities in terrestrial and aquatic microcosms. The insecticide was injected into the trunks of ash trees at a rate of 0.2 gazadirachtin cm(-1) tree diameter in early summer. At the time of senescence, foliar concentrations in most (65%) leaves where at or below detection (<0.01 mg kg(-1) total azadirachtin) and the average concentration among leaves overall at senescence was 0.19 mg kg(-1). Leaves from the azadirachtin-treated trees at senescence were added to microcosms and responses by test organisms were compared to those in microcosms containing leaves from non-treated ash trees (controls). No significant reductions were detected among earthworm survival, leaf consumption rates, growth rates, or cocoon production, aquatic insect survival and leaf consumption rates, and among terrestrial and aquatic microbial decomposition of leaf material in comparison to controls. In a further set of microcosm tests containing leaves from intentional high-dose trees, the only significant, adverse effect detected was a reduction in microbial decomposition of leaf material, and only at the highest test concentration (∼6 mg kg(-1)). Results indicated no significant adverse effects on litter-dwelling earthworms or leaf-shredding aquatic insects at concentrations up to at least 30 × the expected field concentrations at operational rates, and at 6 × expected field concentrations for adverse effects on microbial decomposition. We conclude that when azadirachtin is used as a systemic insecticide in trees for control of insect pests such as the invasive wood-boring beetle, emerald ash borer, resultant foliar concentrations in senescent leaf material are likely to pose little risk of harm to decomposer invertebrates. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

Inorganic pollution around the Qinghai-Tibet Plateau: An overview of the current observations.

PubMed

Wu, Jun; Duan, Dongping; Lu, Jian; Luo, Yongming; Wen, Xiaohu; Guo, Xiaoying; Boman, Brian J

2016-04-15

The Qinghai-Tibet Plateau is the highest geographical unit in the world. Thus, it serves an important role in evaluating long-term ecologic conditions and environmental status and changes over time. This study summarizes major and trace element concentrations in biota and in water and soil. It also pays attention to gaseous pollutant and particle concentrations in air around the Qinghai-Tibet Plateau. The degree of soil heavy metal contamination and the water heavy metal hazard index were respectively evaluated. The contamination degrees of two sampling areas around the Qinghai-Tibet Plateau reached extremely high levels with soil mCd (modified degree of contamination) values exceeding 20. Surprisingly, over 54% of sampling areas showed moderate or more serious soil contamination degree (mCd>1.5). Moreover, the hazard indexes of two important rivers were 1.56 and 7.59, reaching unacceptable level. The potential risk might be beyond our expectation. Therefore, it should be an urgent and top priority to identify and confirm possible pollution sources around the Qinghai-Tibet Plateau. Then, it is imperative to implement feasible and effective environmental quality control strategies. Copyright © 2016 Elsevier B.V. All rights reserved.

Behavioural changes in three species of freshwater macroinvertebrates exposed to the pyrethroid lambda-cyhalothrin: laboratory and stream microcosm studies.

PubMed

Nørum, Ulrik; Friberg, Nikolai; Jensen, Maria R; Pedersen, Jakob M; Bjerregaard, Poul

2010-07-15

Pesticides are transported from crop fields to adjacent streams via surface run-off, drains, groundwater, wind drift and atmospheric deposition and give rise to transient pulse contamination. Although the concentrations observed, typically <10 microg L(-1), cannot be expected to be acutely lethal, effects in streams at the population and ecosystem level have been reported. One of the most conspicuous phenomena associated with these transient pesticide pulses is drift, where large numbers of freshwater invertebrates are carried along by the current and disappear from the contaminated stretch of the stream. The aim of the present study was to evaluate the feasibility of linking laboratory studies of the sublethal effects of pulse exposure to the pyrethroid lambda-cyhalothrin on the locomotory behaviour of stream invertebrates with effects on drift behaviour under more environmentally realistic conditions in stream microcosms. In the laboratory as well as in the microcosms, the order of sensitivities of the three species tested was (with Leuctra nigra being the most sensitive): L. nigra>Gammarus pulex>Heptagenia sulphurea. The LOECs determined for L. nigra (1 ng L(-1)), G. pulex (10 ng L(-1)) and H. sulphurea (100 ng L(-1)) are all within expected environmental concentrations. For the species of invertebrates investigated, it was possible to extrapolate directly from pyrethroid-induced behavioural changes observed in the laboratory to drift under more realistic conditions in stream microcosms. Consequently, the fast and cost-effective video tracking methodology may be applied for screening for potential effects of a wider range of pesticides and other stressors on the locomotory behaviour of freshwater invertebrates. The results indicate that such behavioural changes may be predictive of effects at the ecosystem level. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Biochemical and physiological responses of Carcinus maenas to temperature and the fungicide azoxystrobin.

PubMed

Rodrigues, Elsa Teresa; Moreno, António; Mendes, Tito; Palmeira, Carlos; Pardal, Miguel Ângelo

2015-08-01

Research on the effects of thermal stress is currently pertinent as climate change is expected to cause more severe climate-driven events. Carcinus maenas, a recognised estuarine model organism, was selected to test temperature-dependence of azoxystrobin toxicity, a widely applied fungicide. Crabs' responses were assessed after a 10-d acclimation at different temperatures (5°C, 22°C, and 27°C) of which the last 72h were of exposure to an environmental concentration of azoxystrobin. SOD and GST activities, mitochondrial oxygen consumption rates and protein content, as well as the Coupling Index were determined. The hypothesis proposed that extreme temperatures (5°C and 27°C) and azoxystrobin would affect crabs' responses. Results showed statistically significant different effects of SOD and all oxygen rates measured promoted by temperature, and that neither 30.3μgL(-1) of azoxystrobin nor the combined effect were crab-responsive. Protein content at 5°C was statistically higher when compared with the control temperature (22°C). The Coupling Index revealed both a slight and a drastic decrease of this index promoted by 5°C and 27°C, respectively. Regarding azoxystrobin effects, at 22°C, this index only decreased slightly. However, at extreme temperatures it fell 47% at 5°C and slightly increased at 27°C. Results provided evidence that crabs' responses to cope with low temperatures were more effective than their responses to cope with high temperatures, which are expected in future climate projections. Moreover, crabs are capable of handling environmental concentrations of azoxystrobin. However, the Coupling Index showed that combined stress factors unbalance crabs' natural capability to handle a single stressor. Copyright © 2015 Elsevier Ltd. All rights reserved.

Health-hazard evaluation determination report No. 75-91-489, Alcoa Aluminum Company, Warrick Operations, Newburgh, Indiana

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1978-05-01

A health-hazard evaluation, including mortality and follow-up environmental studies of worker exposure to oil mists, coal tar pitch volatiles (CTPV), and carbon monoxide in the rolling mills of the Alcoa Aluminum Company Warrick Operations, Newburgh, Indiana was conducted. The mortality study was inconclusive due to the small number of expected deaths and inaccurate medical histories. It was impossible to determine if Alcoa employees who died from cancer or ischemic heart disease did so as a result of their work exposure. Results of sampling indicate that employees working in the anode block fabrication and kiln area were exposed to hazardous levelsmore » of CTPV as cyclohexane solubles. Fifteen of 17 extracts contained benzo(a)pyrene. Employees were not exposed to hazardous levels of carbon monoxide and those in the hot mill area and cold mill oil houses were not exposed to oil mist at concentrations which would be expected to result in long-term adverse health effects. Recommendations included: pre-employment and periodic physical examination; environmental monitoring, effective engineering, and administrative controls to reduce exposure to CTPV to the lowest extent possible; disposable protective clothes for workers exposed to CTPV; and prompt decontamination of skin exposed to CTPV.« less

40 CFR 197.14 - What is a reasonable expectation?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 26 2012-07-01 2011-07-01 true What is a reasonable expectation? 197.14 Section 197.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA...

40 CFR 197.14 - What is a reasonable expectation?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 25 2014-07-01 2014-07-01 false What is a reasonable expectation? 197.14 Section 197.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA...

40 CFR 197.14 - What is a reasonable expectation?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 25 2011-07-01 2011-07-01 false What is a reasonable expectation? 197.14 Section 197.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA...

40 CFR 197.14 - What is a reasonable expectation?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 26 2013-07-01 2013-07-01 false What is a reasonable expectation? 197.14 Section 197.14 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS PUBLIC HEALTH AND ENVIRONMENTAL RADIATION PROTECTION STANDARDS FOR YUCCA MOUNTAIN, NEVADA...

TRISO-Coated Fuel Durability Under Extreme Conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reimanis, Ivar; Gorman, Brian; Butt, Darryl

2014-03-30

The PIs propose to examine TRISO-coated particles (SiC and ZrC coatings) in an integrated two-part study. In the first part, experiments will be performed to assess the reaction kinetics of the carbides under CO-CO2 environments at temperatures up to 1800 degree C. Kinetic model will be applied to describe the degradation. Scanning and transmission electron microscopy will be employed to establish the chemical and microstructure evolution under the imposed environmental conditions. The second part of the proposed work focuses on establishing the role of the high temperature, environmental exposure described above on the mechanical behavior of TRISO-coated particles. Electron microscopymore » and other advanced techniques will be subsequently performed to evaluate failure mechanisms. The work is expected to reveal relationships between corrosion reactions, starting material characteristics (polytype of SiC, impurity concentration, flaw distribution), flaw healing behavior, and crack growth.« less

Trace elements in coal ash

USGS Publications Warehouse

Deonarine, Amrika; Kolker, Allan; Doughten, Michael W.

2015-01-01

In this fact sheet, the form, distribution, and behavior of trace elements of environmental interest in samples of coal fly ash were investigated in response to concerns about element mobility in the event of an ash spill. The study includes laboratory-based leaching experiments to examine the behavior of trace elements, such as arsenic (As) and chromium (Cr), in response to key environmental factors including redox conditions (degree of oxygenation), which are known to vary with depth within coal ash impoundments and in natural ecosystems. The experiments show that As dissolves from samples of coal fly ash into simulated freshwater under both oxic (highly oxygenated) and anoxic (poorly oxygenated) conditions, whereas dissolved Cr concentrations are very redox dependent. This U.S. Geological Survey research helps define the distribution of elements such as As in coal ash and shows that element mobility can vary considerably under different conditions expected in the environment.

γ-H2AX as a biomarker for DNA double-strand breaks in ecotoxicology.

PubMed

Gerić, Marko; Gajski, Goran; Garaj-Vrhovac, Vera

2014-07-01

The visualisation of DNA damage response proteins enables the indirect measurement of DNA damage. Soon after the occurrence of a DNA double-strand break (DSB), the formation of γ-H2AX histone variants is to be expected. This review is focused on the potential use of the γ-H2AX foci assay in assessing the genotoxicity of environmental contaminants including cytostatic pharmaceuticals, since standard methods may not be sensitive enough to detect the damaging effect of low environmental concentrations of such drugs. These compounds are constantly released into the environment, potentially representing a threat to water quality, aquatic organisms, and, ultimately, human health. Our review of the literature revealed that this method could be used in the biomonitoring and risk assessment of aquatic systems affected by wastewater from the production, usage, and disposal of cytostatic pharmaceuticals. Copyright © 2014 Elsevier Inc. All rights reserved.

Ambient air concentrations exceeded health-based standards for fine particulate matter and benzene during the Deepwater Horizon oil spill.

PubMed

Nance, Earthea; King, Denae; Wright, Beverly; Bullard, Robert D

2016-02-01

The Deepwater Horizon oil spill is considered one of the largest marine oil spills in the history of the United States. Air emissions associated with the oil spill caused concern among residents of Southeast Louisiana. The purpose of this study was to assess ambient concentrations of benzene (n=3,887) and fine particulate matter (n=102,682) during the oil spill and to evaluate potential exposure disparities in the region. Benzene and fine particulate matter (PM2.5) concentrations in the targeted parishes were generally higher following the oil spill, as expected. Benzene concentrations reached 2 to 19 times higher than background, and daily exceedances of PM2.5 were 10 to 45 times higher than background. Both benzene and PM2.5 concentrations were considered high enough to exceed public health criteria, with measurable exposure disparities in the coastal areas closer to the spill and clean-up activities. These findings raise questions about public disclosure of environmental health risks associated with the oil spill. The findings also provide a science-based rationale for establishing health-based action levels in future disasters. Benzene and particulate matter monitoring during the Deepwater Horizon oil spill revealed that ambient air quality was a likely threat to public health and that residents in coastal Louisiana experienced significantly greater exposures than urban residents. Threshold air pollution levels established for the oil spill apparently were not used as a basis for informing the public about these potential health impacts. Also, despite carrying out the most comprehensive air monitoring ever conducted in the region, none of the agencies involved provided integrated analysis of the data or conclusive statements about public health risk. Better information about real-time risk is needed in future environmental disasters.

Glyphosate and aminomethylphosphonic acid chronic risk assessment for soil biota.

PubMed

von Mérey, Georg; Manson, Philip S; Mehrsheikh, Akbar; Sutton, Peter; Levine, Steven L

2016-11-01

Glyphosate is a broad-spectrum herbicide used widely in agriculture, horticulture, private gardens, and public infrastructure, where it is applied to areas such as roadsides, railway tracks, and parks to control the growth of weeds. The exposure risk from glyphosate and the primary soil metabolite aminomethylphosphonic acid (AMPA) on representative species of earthworms, springtails, and predatory soil mites and the effects on nitrogen-transformation processes by soil microorganisms were assessed under laboratory conditions based on internationally recognized guidelines. For earthworms, the reproductive no-observed-effect concentration (NOEC) was 472.8 mg glyphosate acid equivalent (a.e.)/kg dry soil, which was the highest concentration tested, and 198.1 mg/kg dry soil for AMPA. For predatory mites, the reproductive NOEC was 472.8 mg a.e./kg dry soil for glyphosate and 320 mg/kg dry soil for AMPA, the highest concentrations tested. For springtails, the reproductive NOEC was 472.8 mg a.e./kg dry soil for glyphosate and 315 mg/kg dry soil for AMPA, the highest concentrations tested. Soil nitrogen-transformation processes were unaffected by glyphosate and AMPA at 33.1 mg a.e./kg soil and 160 mg/kg soil, respectively. Comparison of these endpoints with worst-case soil concentrations expected for glyphosate (6.62 mg a.e./kg dry soil) and AMPA (6.18 mg/kg dry soil) for annual applications at the highest annual rate of 4.32 kg a.e./ha indicate very low likelihood of adverse effects on soil biota. Environ Toxicol Chem 2016;35:2742-2752. © 2016 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC. © 2016 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

Evaluation of a Public Health Intervention to Lower Mercury Exposure from Fish Consumption in Bermuda

PubMed Central

Dewailly, Eric; Rouja, Philippe; Forde, Martin; Peek-Ball, Cheryl; Côté, Suzanne; Smith, Emma; Drescher, Olivia; Robertson, Lyndon

2012-01-01

Objectives To assess the efficacy of a public health intervention to reduce blood mercury (Hg) concentration levels in pregnant Bermudian women. Methods In 2003, we conducted a study entitled “Prenatal exposure of the Bermudian Population to Environmental Contaminants” which provided Bermuda’s first baseline data on prenatal exposure to several environmental contaminants, including Hg. The mean Hg concentration from 42 healthy newborns measured in umbilical cord blood was 41.3 nmol/L, ranging from 5–160 nmol/L. This concentration was much higher than expected, being approximately 8 times the general levels found in Canada and the U.S. Furthermore, we estimated that 85% of total Hg measured was in the form of methylmercury (MeHg), indicating that seafood consumption was the primary source of Hg exposure during pregnancy in Bermuda. Locally sourced seafood was identified as the most significant possible contributory source of Hg exposure. In 2005 the authors began a complementary research programme to study the levels of Hg in local commercial fish species. Coming out of this research were specific local fish consumption guidelines issued by the Department of Health advising pregnant women to avoid those local fish species found to be high in Hg while still encouraging consumption of fish species having lower Hg levels. Results In 2010, under another research initiative, we returned to Bermuda to carry out another evaluation of Hg in human blood. Hg was measured in the blood of 49 pregnant women. The arithmetic mean Hg blood concentration was 6.6 nmol/L and the geometric mean 4.2 nmol/L. The maximum concentration found was 24 nmol/L. Conclusions Hg exposure of Bermudian pregnant women has dropped significantly by a factor of around 5 since the foetal cord blood study in 2003. PMID:23077607

Evaluation of a public health intervention to lower mercury exposure from fish consumption in Bermuda.

PubMed

Dewailly, Eric; Rouja, Philippe; Forde, Martin; Peek-Ball, Cheryl; Côté, Suzanne; Smith, Emma; Drescher, Olivia; Robertson, Lyndon

2012-01-01

To assess the efficacy of a public health intervention to reduce blood mercury (Hg) concentration levels in pregnant Bermudian women. In 2003, we conducted a study entitled "Prenatal exposure of the Bermudian Population to Environmental Contaminants" which provided Bermuda's first baseline data on prenatal exposure to several environmental contaminants, including Hg. The mean Hg concentration from 42 healthy newborns measured in umbilical cord blood was 41.3 nmol/L, ranging from 5-160 nmol/L. This concentration was much higher than expected, being approximately 8 times the general levels found in Canada and the U.S. Furthermore, we estimated that 85% of total Hg measured was in the form of methylmercury (MeHg), indicating that seafood consumption was the primary source of Hg exposure during pregnancy in Bermuda. Locally sourced seafood was identified as the most significant possible contributory source of Hg exposure. In 2005 the authors began a complementary research programme to study the levels of Hg in local commercial fish species. Coming out of this research were specific local fish consumption guidelines issued by the Department of Health advising pregnant women to avoid those local fish species found to be high in Hg while still encouraging consumption of fish species having lower Hg levels. In 2010, under another research initiative, we returned to Bermuda to carry out another evaluation of Hg in human blood. Hg was measured in the blood of 49 pregnant women. The arithmetic mean Hg blood concentration was 6.6 nmol/L and the geometric mean 4.2 nmol/L. The maximum concentration found was 24 nmol/L. Hg exposure of Bermudian pregnant women has dropped significantly by a factor of around 5 since the foetal cord blood study in 2003.

Isoperms: An Environmental Management Tool.

ERIC Educational Resources Information Center

Sebera, Donald K.

A quantitative tool, the isoperm method, is described; it quantifies the effect of environmental factors of temperature (T) and percent relative humidity (%RH) on the anticipated useful life expectancy of paper-based collections. The isoperm method provides answers to questions of the expected lifetime of the collection under various temperature…

77 FR 56840 - Meeting of the Environmental Financial Advisory Board-Public Notice

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-14

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9727-8] Meeting of the Environmental Financial Advisory Board... meeting. SUMMARY: The United States Environmental Protection Agency's (EPA) Environmental Financial... expected on the following topics: Clean air technology; tribal environmental programs; transit-oriented...

[Construction and validation of a socio-environmental vulnerability index for monitoring and management of natural disasters in the state of Rio de Janeiro, Brazil].

PubMed

Guimarães, Raphael Mendonça; Mazoto, Maíra Lopes; Martins, Raphael Nascimento; do Carmo, Cleber Nascimento; Asmus, Carmen Ildes Fróes

2014-10-01

Floods account for approximately 40% of natural disasters that occur around the world and they are therefore considered a major public health problem. While floods constitute a global problem, data from the International Strategy for Disaster Reduction showed that almost all of the deaths or individuals affected are concentrated in developing countries. It is assumed that, although they have natural causes, the consequences of floods also involve social issues. To try to predict such vulnerability in the occurrence of natural disasters, a social and environmental index that shows the degree of vulnerability of a location was developed in this paper. This index was developed using multivariate analysis involving factor analysis and demographic, social and environmental variables. The index was applied in the municipalities of the state of Rio de Janeiro and compared with the official figures of the Civil Defense Unit. The results found suggest that the proposed index meets the expectation of predicting the vulnerability of the local population.

The skin microbiome: current perspectives and future challenges

PubMed Central

Chen, Yiyin Erin; Tsao, Hensin

2013-01-01

Complex communities of bacteria, fungi, and viruses thrive on our skin. The composition of these communities depends on skin characteristics, such as sebaceous gland concentration, moisture content, and temperature, as well as on host genetics and exogenous environmental factors. Recent metagenomic studies have uncovered a surprising diversity within these ecosystems and have fostered a new view of commensal organisms as playing a much larger role in immune modulation and epithelial health than previously expected. Understanding microbe-host interactions and discovering the factors that drive microbial colonization will help us understand the pathogenesis of skin diseases and develop new promicrobial and antimicrobial therapeutics. PMID:23489584

Screening of Pesticides with the Potential of Inducing DSB and Successive Recombinational Repair

PubMed Central

2017-01-01

A study was realized to ascertain whether eight selected pesticides would induce double strand breaks (DSB) in lymphocyte cultures and whether this damage would induce greater levels of proteins Rad51 participating in homologous recombination or of p-Ku80 participating in nonhomologous end joining. Only five pesticides were found to induce DSB of which only glyphosate and paraoxon induced a significant increase of p-Ku80 protein, indicating that nonhomologous end joining recombinational DNA repair system would be activated. The type of gamma-H2AX foci observed was comparable to that induced by etoposide at similar concentrations. These results are of importance since these effects occurred at low concentrations in the micromolar range, in acute treatments to the cells. Effects over longer exposures in actual environmental settings are expected to produce cumulative damage if repeated events of recombination take place over time. PMID:29129974

Evaluation of the Influence That Was Produced by Phytoremediation of Soil Microorganisms at Oil Showings

NASA Astrophysics Data System (ADS)

Kaimi, Etsuko; Kawakita, Morikazu; Mukaidani, Tsukasa; Fujiwara, Kazuhiro; Okada, Shin-Ichi; Yasuda, Yoshio

Phytoremediation has been identified as a potentially environmentally friendly and cost effective technique for the treatment of contaminated soil. However, phytoremediation has an unknown mechanism. In this study, we focus on the effects of the cultivation of Italian ryegrass on the soil microbes collected at oil showings, which were expected to have a variety of crude oil degradable microorganisms. We evaluated the number of crude oil degradable microorganism, microbial activity, microflora using the PCR-DGGE method and the change in the concentration of crude oil in the soil. The results indicated that the microflora was affected by the cultivation of Itarian ryegrass, and that the microbial activity and the number of crude oil degradable microorganisms were also improved by the cultivation. Moreover, the concentration of crude oil in the rhizosphere soil decreased significantly when compared to the uncultivated soil. These results suggested that cultivation could regulate microflora selectively, which degraded crude oil.

Effect of chronic altitude hypoxia on hematologic and glycolytic parameters.

PubMed

Clench, J; Ferrell, R E; Schull, W J

1982-05-01

The physiological effect of chronic exposure to altitude hypoxia on the glycolytic intermediates, adenosine triphosphate and 2,3-diphosphoglyceric acid, and the hematologic parameters, hemoglobin, hematocrit, and mean cell hemoglobin concentration, has been examined in an indigenous population, the Aymara, of the Departamento de Arica, Chile. This population normally resides at three altitudes: the coast (0-500 m), the sierra (2,500-3,500 m), and the altiplano (above 4,200 m). After isolation of altitude from other environmental factors (age, sex, body build, ethnicity, smoking, and residential permanence), an increase in 2,3-diphosphoglycerate and a decrease in adenosine triphosphate was observed. Both hemoglobin and hematocrit increased as expected, but mean cell hemoglobin concentration declined. It is proposed that a decline in the activity of a single enzyme, pyruvate kinase, can account for these observed changes and suggests a pivotal role for pyruvate kinase in the physiological adaptation to altitude hypoxia.

137Cs activity concentration in mosses in the Calabria region, south of Italy

NASA Astrophysics Data System (ADS)

Caridi, F.; Belvedere, A.; D'Agostino, M.; Marguccio, S.

2017-05-01

Many studies carried out after the Chernobyl nuclear accident in 1986 showed that mosses are suitable bioindicators of the radioactive fall-out, given their long life expectancy. 137Cs activity concentration was measured through HPGe gamma spectrometry in different mosses (Hypnum Cupressiforme, Hypnum Andoi, Homalothecium Sericeum, Philonotis Fontana), collected, in 2008 and 2015, from four sampling sites in the Calabria region, south of Italy. Experimental specific activities allowed us to determine the effective and the biological half-time of 137Cs for the investigated plants. The effective half-time was found in the range from (4.2 ± 1.1) to (7.4 ± 1.8) years; the biological half-time varied from (4.9 ± 1.3) to (9.9 ± 2.4) years. Data reported in this article provide useful information on the environmental risk of the studied area and can be further used for a radiological mapping.

Behavioral determinants of occupational exposure to chemical agents.

PubMed

Meijman, T F; Ulenbelt, P; Lumens, M E; Herber, R F

1996-01-01

In the demand-control model (see T. Theorell & R. A. Karasek, 1996), it is hypothesized that workers in active jobs (high demands-high decision latitude) can exert effective coping strategies when confronted with environmental stessors. Thus, when exposed to similar levels of a chemical agent, lower concentrations of this agent in blood could be expected in these workers in comparison with workers in passive jobs. This theory was tested in 2 studies of lead-exposed workers: 18 male Caucasian workers from an electric accumulatory factory and 18 male Caucasian workers from a lead smelting factory. The results did not follow the hypothesized outcomes. In the work environment of the workers in active jobs, lower concentrations of lead in air were measured, but higher levels of lead in blood were observed in these workers. The opposite was true of workers in passive jobs. Differences in hygienic behavior at work may explain these unexpected results.

Twenty two years of sewage sludge marine disposal monitoring in the Eastern Mediterranean Sea: Impact on sediment quality and infauna and the response to load reduction.

PubMed

Kress, N; Shoham-Frider, E; Galil, B S

2016-09-15

Effects of sewage sludge disposal on sediments and infauna are presented in a unique long-term (22years) data set from the Eastern Mediterranean. While organic carbon (Corg) and metals affected sediment quality in an area which size varied seasonally, the infauna exhibited seasonal "boom and bust" cycle. Metal concentrations declined following load reduction. However, Corg did not decrease and infaunal abundance, closely related to Corg, varied with changes in environmental forcing. Mild winters affected the infaunal populations at the heavily impacted stations, due to anoxic conditions. Planned cessation of disposal is estimated to reduce Corg and metal concentrations to pre-discharge levels. Yet the resettling biota is expected to differ significantly from the pre-discharge one and consist in large part of Erythraean non indigenous species. Copyright © 2016 Elsevier Ltd. All rights reserved.

Scopolamine in racing horses: trace identifications associated with dietary or environmental exposure.

PubMed

Brewer, Kimberly; Dirikolu, Levent; Hughes, Charlie G; Tobin, Thomas

2014-03-01

Scopolamine (L-hyoscine) identifications, often in small-number clusters, have been reported worldwide in performance horses over the last 30 years. Scopolamine is an Association of Racing Commissioners International (ARCI) class 3, penalty class B, substance with potential to affect performance. As such, scopolamine identification(s) in race or performance horses can result in significant penalties for the connections of the horse(s). Reviewed here is the worldwide distribution of scopolamine containing plants (primarily Datura spp.), with estimates of their potential toxicity to horses through dietary and/or environmental exposure. Also reviewed are the basic pharmacology of scopolamine and its precursor, urinary concentrations following feedstuff exposure, and the probable pharmacological/forensic significance of such findings. Based on an overview of the world literature on scopolamine, the expected characteristics of inadvertent environmental exposure are also presented with a view to making clear the potential of scopolamine identifications, with or without atropine, as a direct and expected outcome of both the worldwide distribution of scopolamine-containing plants and the sensitivity of modern equine drug testing. It is of particular interest that only 2/30 reported post-event equine identifications of scopolamine have been associated with atropine, suggesting that failure to identify atropine is not a biomarker of pharmaceutical administration of scopolamine. Available quantitative information associated with scopolamine identifications is consistent with the 75 ng/mL regulatory threshold for scopolamine currently used in Louisiana racing in the USA and the 30 ng/mL reporting threshold in effect in European racing. Copyright © 2013 Elsevier Ltd. All rights reserved.

Use of questionnaires and an expert panel to judge the environmental consequences of chemical spills for the development of an environment-accident index.

PubMed

Andersson, Asa Scott; Stjernström, Olof; Fängmark, Ingrid

2005-05-01

Assessing the environmental consequences of a chemical accident is a complex task. To date, the methods used to evaluate the environmental effects of an acute release of a chemical have often been based on measurements of chemical and physical variables deemed to be important, such as the concentration of the chemical. However, a broader strategy is needed to predict the environmental consequences of potential accidents during the planning process. An Environment-Accident Index (EAI), a simple tool based on such a strategy, has been developed to facilitate the consideration of a multitude of influential variables. The objectives of this study were to evaluate whether questionnaire-based expert panel's judgements could provide useful data on the environmental consequences of chemical spills, and an effective basis for further development of the EAI. As expected, the judgements did not agree perfectly, but they do give rough indications of the environmental effects, and highlight consistent trends that should be useful inputs for planning, prevention and decontamination processes. The different accidents were also judged to have caused everything from minor to very major effects in the environment, implying that a wide range of accident scenarios were represented in the material and covered by the EAI. Therefore, questionnaires and expert panel judgements can be used to collect useful data for estimating the likely environmental consequences of chemical accidents and for further development of the EAI.

Anger and retribution after collective overuse: the role of blaming and environmental uncertainty in social dilemmas.

PubMed

de Kwaadsteniet, Erik W; van Dijk, Eric; Wit, Arjaan; De Cremer, David

2010-01-01

This article investigates how group members respond to one another when collective overuse occurs. The authors argue that interpersonal reactions after overuse in a common-resource dilemma are largely determined by the environmental characteristics of the social dilemma. More specifically, under environmental certainty they expect people to show more anger to group members than under uncertainty (Study 1). Additionally, they expect stronger retributive reactions to high harvesters than to moderate harvesters, and they expect this difference to be larger under certainty than under uncertainty (Study 2 and 3). Moreover, they predict that these effects are mediated by blaming. The results of three experiments corroborate these predictions.

Environmental factors determining ammonia-oxidizing organism distribution and diversity in marine environments.

PubMed

Bouskill, Nicholas J; Eveillard, Damien; Chien, Diana; Jayakumar, Amal; Ward, Bess B

2012-03-01

Ammonia-oxidizing bacteria (AOB) and archaea (AOA) play a vital role in bridging the input of fixed nitrogen, through N-fixation and remineralization, to its loss by denitrification and anammox. Yet the major environmental factors determining AOB and AOA population dynamics are little understood, despite both groups having a wide environmental distribution. This study examined the relative abundance of both groups of ammonia-oxidizing organisms (AOO) and the diversity of AOA across large-scale gradients in temperature, salinity and substrate concentration and dissolved oxygen. The relative abundance of AOB and AOA varied across environments, with AOB dominating in the freshwater region of the Chesapeake Bay and AOA more abundant in the water column of the coastal and open ocean. The highest abundance of the AOA amoA gene was recorded in the oxygen minimum zones (OMZs) of the Eastern Tropical South Pacific (ETSP) and the Arabian Sea (AS). The ratio of AOA : AOB varied from 0.7 in the Chesapeake Bay to 1600 in the Sargasso Sea. Relative abundance of both groups strongly correlated with ammonium concentrations. AOA diversity, as determined by phylogenetic analysis of clone library sequences and archetype analysis from a functional gene DNA microarray, detected broad phylogenetic differences across the study sites. However, phylogenetic diversity within physicochemically congruent stations was more similar than would be expected by chance. This suggests that the prevailing geochemistry, rather than localized dispersal, is the major driving factor determining OTU distribution. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Phytoestrogens and mycotoxins in Iowa streams: An examination of underinvestigated compounds in agricultural basins

USGS Publications Warehouse

Kolpin, Dana W.; Hoerger, Corinne C.; Meyer, Michael T.; Wettstein, Felix E.; Hubbard, Laura E.; Bucheli, Thomas D.

2010-01-01

This study provides the first broad-scale investigation on the spatial and temporal occurrence of phytoestrogens and mycotoxins in streams in the United States. Fifteen stream sites across Iowa were sampled five times throughout the 2008 growing season to capture a range of climatic and crop-growth conditions. Basin size upstream from sampling sites ranged from 7 km2 to >836,000 km2 Atrazine (herbicide) also was measured in all samples as a frame-of-reference agriculturally derived contaminant. Target compounds were frequently detected in stream samples: atrazine (100%), formononetin (80%), equol (45%), deoxynivalenol (43%), daidzein (32%), biochanin A (23%), zearalenone (13%), and genistein (11%). The nearly ubiquitous detection of formononetin (isoflavone) suggests a widespread agricultural source, as one would expect with the intense row crop and livestock production present across Iowa. Conversely, the less spatially widespread detections of deoxynivalenol (mycotoxin) suggest a more variable source due to the required combination of proper host and proper temperature and moisture conditions necessary to promote Fusarium spp. infections. Although atrazine concentrations commonly exceeded 100 ng L-1 (42/75 measurements), only deoxynivalenol (6/56 measurements) had concentrations that occasionally exceeded this level. Temporal patterns in concentrations varied substantially between atrazine, formononetin, and deoxynivalenol, as one would expect for contaminants with different source inputs and processes of formation and degradation. The greatest phytoestrogen and mycotoxin concentrations were observed during spring snowmelt conditions. Phytoestrogens and mycotoxins were detected at all sampling sites regardless of basin size. The ecotoxicological effects from long-term, low-level exposures to phytoestrogens and mycotoxins or complex chemicals mixtures including these compounds that commonly take place in surface water are poorly understood and have yet to be systematically investigated in environmental studies.

Phytoestrogens and mycotoxins in Iowa streams: An examination of underinvestigated compounds in agricultural basins

USGS Publications Warehouse

Kolpin, D.W.; Hoerger, C.C.; Meyer, M.T.; Wettstein, F.E.; Hubbard, L.E.; Bucheli, T.D.

2010-01-01

This study provides the first broad-scale investigation on the spatial and temporal occurrence of phytoestrogens and mycotoxins in streams in the United States. Fifteen stream sites across Iowa were sampled five times throughout the 2008 growing season to capture a range of climatic and crop-growth conditions. Basin size upstream from sampling sites ranged from 7 km2 to >836,000 km2. Atrazine (herbicide) also was measured in all samples as a frame-ofreference agriculturally derived contaminant. Target compounds were frequently detected in stream samples: atrazine (100%), formononetin (80%), equol (45%), deoxynivalenol (43%), daidzein (32%), biochanin A (23%), zearalenone (13%), and genistein (11%). Th e nearly ubiquitous detection of formononetin (isoflavone) suggests a widespread agricultural source, as one would expect with the intense row crop and livestock production present across Iowa. Conversely, the less spatially widespread detections of deoxynivalenol (mycotoxin) suggest a more variable source due to the required combination of proper host and proper temperature and moisture conditions necessary to promote Fusarium spp. infections. Although atrazine concentrations commonly exceeded 100 ng L-1 (42/75 measurements), only deoxynivalenol (6/56 measurements) had concentrations that occasionally exceeded this level. Temporal patterns in concentrations varied substantially between atrazine, formononetin, and deoxynivalenol, as one would expect for contaminants with different source inputs and processes of formation and degradation. The greatest phytoestrogen and mycotoxin concentrations were observed during spring snowmelt conditions. Phytoestrogens and mycotoxins were detected at all sampling sites regardless of basin size. The ecotoxicological effects from long-term, low-level exposures to phytoestrogens and mycotoxins or complex chemicals mixtures including these compounds that commonly take place in surface water are poorly understood and have yet to be systematically investigated in environmental studies. Copyright ?? 2010 by the American Society of Agronomy.

Marine phytoplankton stoichiometry mediates nonlinear interactions between nutrient supply, temperature, and atmospheric CO2

NASA Astrophysics Data System (ADS)

Moreno, Allison R.; Hagstrom, George I.; Primeau, Francois W.; Levin, Simon A.; Martiny, Adam C.

2018-05-01

Marine phytoplankton stoichiometry links nutrient supply to marine carbon export. Deviations of phytoplankton stoichiometry from Redfield proportions (106C : 1P) could therefore have a significant impact on carbon cycling, and understanding which environmental factors drive these deviations may reveal new mechanisms regulating the carbon cycle. To explore the links between environmental conditions, stoichiometry, and carbon cycling, we compared four different models of phytoplankton C : P: a fixed Redfield model, a model with C : P given as a function of surface phosphorus concentration (P), a model with C P given as a function of temperature, and a new multi-environmental model that predicts C : P as a function of light, temperature, and P. These stoichiometric models were embedded into a five-box ocean circulation model, which resolves the three major ocean biomes (high-latitude, subtropical gyres, and tropical upwelling regions). Contrary to the expectation of a monotonic relationship between surface nutrient drawdown and carbon export, we found that lateral nutrient transport from lower C : P tropical waters to high C : P subtropical waters could cause carbon export to decrease with increased tropical nutrient utilization. It has been hypothesized that a positive feedback between temperature and pCO2, atm will play an important role in anthropogenic climate change, with changes in the biological pump playing at most a secondary role. Here we show that environmentally driven shifts in stoichiometry make the biological pump more influential, and may reverse the expected positive relationship between temperature and pCO2, atm. In the temperature-only model, changes in tropical temperature have more impact on the Δ pCO2, atm (˜ 41 ppm) compared to subtropical temperature changes (˜ 4.5 ppm). Our multi-environmental model predicted a decline in pCO2, atm of ˜ 46 ppm when temperature spanned a change of 10 °C. Thus, we find that variation in marine phytoplankton stoichiometry and its environmental controlling factors can lead to nonlinear controls on pCO2, atm, suggesting the need for further studies of ocean C : P and the impact on ocean carbon cycling.

Are Expectations the Missing Link between Life History Strategies and Psychopathology?

PubMed

Kavanagh, Phillip S; Kahl, Bianca L

2018-01-01

Despite advances in knowledge and thinking about using life history theory to explain psychopathology there is still a missing link. That is, we all have a life history strategy, but not all of us develop mental health problems. We propose that the missing link is expectations - a mismatch between expected environmental conditions (including social) set by variations in life history strategies and the current environmental conditions. The mismatch hypothesis has been applied at the biological level in terms of health and disease and we believe that it can also be applied more broadly at the psychological level in terms of perceived expectations in the social environment and the resulting distress-psychopathology-that manifests when our expectations are not met.

Pyrethroid sorption to Sacramento River suspended solids and bed sediments

PubMed Central

Fojut, Tessa L.; Young, Thomas M.

2011-01-01

Sorption of pyrethroid insecticides to solid materials will typically dominate the fate and transport of these hydrophobic compounds in aquatic environments. Batch reactor isotherm experiments were performed with bifenthrin and λ-cyhalothrin with suspended material and bed sediment collected from the Sacramento River, CA. These batch reactor experiments were performed with low spiking concentrations and a long equilibration time (28 d) to be more relevant to environmental conditions. Sorption to suspended material and bed sediment was compared to examine the role of differential sorption between these phases in the environmental transport of pyrethroids. The equilibrium sorption data were fit to the Freundlich isotherm model and fit with r2 > 0.87 for all experiments. Freundlich exponents ranged from 0.72 ± 0.19 to 1.07 ± 0.050, indicating sorption nonlinearity for some of the experimental conditions and linearity for others over the concentration range tested. The Freundlich capacity factors were larger for the suspended solids than for the bed sediments and the suspended material had a higher specific surface area and higher organic carbon content compared to the bed sediment. Calculated organic carbon-normalized distribution coefficients were larger than those previously reported in the literature by approximately an order of magnitude and ranged from 106.16 to 106.68 at an equilibrium aqueous concentration of 0.1 µg/L. Higher than expected sorption of pyrethroids to the tested materials may be explained by sorption to black carbon and/or mineral surfaces. PMID:21191877

Developments in the analytical chemistry of arsenic to support teaching and learning through research in environmental topics

NASA Astrophysics Data System (ADS)

Ampiah-Bonney, Richmond Jerry

Two manifolds were designed to determine phosphate concentrations. The linear range for the 2-channel manifold was 0 to 30 mg L-1, and that for the 3-channel manifold was 0 to 400 mg L-1. Optimized conditions for the determination of arsenic with molybdenum-blue method were 0.5% w/v ascorbic acid, 0.4 M sulfuric acid in the molybdate solution and 80°C reaction temperature. A method for determination of arsenic using pervaporation flow injection hydride generation with visible spectrophotometry was developed. The method was sensitive for low arsenic concentrations (≤ 10 mug L-1), with sensitivity decreasing as arsenic concentration increased. There was no heating required, and the pervaporation membrane transferred only arsine. The analytical performance of two arsenic test kits was assessed. The Alpha Environmental kit cannot be recommended for arsenic measurement in water. The Hach kit was reliable for measuring arsenic concentrations greater than 70 mug L-1. A modified reaction tube was constructed that allowed NaBH4 solution to be delivered into the reaction mixture to replace zinc powder in the Hach kit, with no loss of gases. A more quantitative way of measuring arsenic using the Hach kit was developed by measuring the B-value of the color of jpeg images of test strips taken by a desktop scanner. Leersia oryzoides grown in soil amended with 110 mg kg-1arsenic extracted up to 305 mug g-1 and 272 mug g-1 arsenic into its shoots and roots respectively, giving a shoot:root quotient (SRQ) of 1.12 and phytoextraction coefficients (PEC) up to 1.3 in greenhouse experiments. Five supervised arsenic-related projects were reported. All except one of these reports fell short of the standards acceptable for a publishable manuscript. Factors such as high expectations, competitive entrance requirements and good motivation were responsible for the publishable report. For the remaining reports, problems with working in a team, relatively low expectations and lack of motivation were responsible. A laboratory-based research subject was successfully investigated in middle school classrooms. The program had been run for four consecutive years. Collaboration with the classroom teacher ensured that the program agreed with the school curriculum. All participants recommended continuation of this program.

Environmental protection requirements for scout/shuttle auxiliary stages

NASA Technical Reports Server (NTRS)

Qualls, G. L.; Kress, S. S.; Storey, W. W.; Ransdell, P. N.

1980-01-01

The requirements for enabling the Scout upper stages to endure the expected temperature, mechanical shock, acoustical and mechanical vibration environments during a specified shuttle mission were determined. The study consisted of: determining a shuttle mission trajectory for a 545 kilogram (1200 pound) Scout payload; compilation of shuttle environmental conditions; determining of Scout upper stages environments in shuttle missions; compilation of Scout upper stages environmental qualification criteria and comparison to shuttle mission expected environments; and recommendations for enabling Scout upper stages to endure the exptected shuttle mission environments.

[Global environment and health--with emphasis on world nutritional status].

PubMed

Suzuki, T

1993-12-01

Forthcoming global environmental changes threaten to endanger human survival through direct and indirect influences. In this paper, the contemporary world food supply situation and resultant nutritional status was first reviewed on by country and region. When compared with the nutritional energy requirement, countries with an inadequate food supply were concentrated in the developing world, in particular in some parts of Africa. The life expectancy at birth is clearly shorter in such countries, and peoples of African countries with an inadequate food supply have shorter life expectancies than other countries with a similar inadequacy. Global warning is likely to decrease food production in some parts of the world. According to the present estimation using various methods, a future crisis of food production may occur in African countries which are at present most vulnerable to food shortages, as well as in countries which are presently food exporters. Thus, a future crisis of human health conditions caused by the imbalance of food production and trade may be least avoidable in the region of present predicament.

Ground-water quality, Cook Inlet Basin, Alaska, 1999

USGS Publications Warehouse

Glass, Roy L.

2001-01-01

As part of the U.S. Geological Survey?s National Water-Quality Assessment Program, ground-water samples were collected from 34 existing wells in the Cook Inlet Basin in south-central Alaska during 1999. All ground-water samples were from aquifers composed of glacial or alluvial sediments. The water samples were used to determine the occurrence and distribution of selected major ions, nutrients, trace elements, volatile organic compounds, pesticides, radioisotopes, and environmental isotopes. Of 34 samples, 29 were from wells chosen by using a grid-based random-selection process. Water samples from five major public-supply wells also were collected. Radon-222 and arsenic concentrations exceeded drinking-water standards proposed by the U.S. Environmental Protection Agency in 39 and 18 percent of sampled wells, respectively. The highest radon concentration measured during this study was 610 picocuries per liter; 12 of 31 samples exceeded the proposed maximum contaminant level of 300 picocuries per liter. The highest arsenic concentration was 29 micrograms per liter; 6 of 34 samples exceeded the proposed maximum contaminant level of 10 micrograms per liter. Human activities may be increasing the concen- tration of nitrate in ground water, but nitrate concentrations in all samples were less than the maximum contaminant level of 10 milligrams per liter as nitrogen. Concentrations of nitrate were highest in Anchorage and were as great as 4.8 milligrams per liter as nitrogen. Dissolved-solids concentrations ranged from 77 to 986 milligrams per liter; only 2 of 34 wells yielded water having greater than 500 milligrams per liter. Iron and manganese concentrations exceeded secondary maximum contaminant levels in 18 and 42 percent of samples, respectively. Concentrations of all pesticides and volatile organic compounds detected in ground-water samples were very low, less than 1 microgram per liter. No pesticide or volatile organic compounds were detected at concentrations exceeding drinking-water standards or guidelines. Water samples from one-half of the wells sampled had no detectable concentrations of pesticides or volatile organic carbons, at the parts-per-billion level. Concentrations of stable isotopes of hydrogen and oxygen in ground-water samples were similar to concentrations expected for modern precipitation and for water that has been affected by evaporation. Tritium activities and concentrations of chlorofluorocarbons indicated that the water samples collected from most wells were recharged less than 50 years ago.

Do freshwater mussel shells record road-salt pollution?

NASA Astrophysics Data System (ADS)

O'Neil, Dane D.; Gillikin, David P.

2014-11-01

Road-salt pollution in streams in the Northeastern United States has become a major concern, but historical data are scarce. Freshwater bivalve shells have the ability to record past environmental information, and may act as archives of road-salt pollution. We sampled Elliptio complanata shells from four streams, as well as specimens collected in 1877. Average [Na/Ca]shell was highest in modern shells from the stream with the highest sodium concentrations, and low in shells collected from this same stream in 1877 as well as in the shells from other streams, suggesting that [Na/Ca]shell serves as a proxy for road-salt pollution. We expected higher [Na/Ca]shell in winter and spring. However, high-resolution [Na/Ca]shell analyses along the growth axis of one shell did not reveal any clear subannual patterns, which could be the result of shell growth cessation in winter and/or during periods of high stream sodium concentrations. Therefore, bulk [Na/Ca]shell analysis from multiple shells can be used as a proxy of large changes in stream sodium concentrations, but high-resolution variations in stream sodium concentrations do not seem to be recorded in the shells.

Direct comparison of extinction coefficients derived from Mie-scattering lidar and number concentrations of particles, subjective weather report in Japan

NASA Astrophysics Data System (ADS)

Shimizu, Atsushi; Sugimoto, Nobuo; Matsui, Ichiro; Nishizawa, Tomoaki

2015-03-01

Two components of the lidar extinction coefficient, the dust extinction and the spherical particles extinction, were obtained from observations made by the National Institute for Environmental Studies lidar network in Japan. These two extinctions were compared with the number concentration of particles measured by an optical particle counter, and with subjective weather reports recorded at the nearest meteorological observatories. The dust extinction corresponded well with the number concentration of large particles with diameters as great as 5 μm and during dry conditions with the number concentration of particles larger than 2 μm. The relationship between the spherical particle extinction and the number of small particles was nearly constant under all conditions. Asian dust was sometimes reported by meteorological observatories in the period of lower dust extinction. This indicates contradicting relationship between human-eye based reports and optical characteristics observed by lidars in some cases. The most consistent results between lidar observation and meteorological reports were obtained in dry mist conditions, in which lidars exhibited higher spherical extinction as expected by the definition of the atmospheric phenomenon of dry mist or haze.

Do freshwater mussel shells record road-salt pollution?

PubMed Central

O'Neil, Dane D.; Gillikin, David P.

2014-01-01

Road-salt pollution in streams in the Northeastern United States has become a major concern, but historical data are scarce. Freshwater bivalve shells have the ability to record past environmental information, and may act as archives of road-salt pollution. We sampled Elliptio complanata shells from four streams, as well as specimens collected in 1877. Average [Na/Ca]shell was highest in modern shells from the stream with the highest sodium concentrations, and low in shells collected from this same stream in 1877 as well as in the shells from other streams, suggesting that [Na/Ca]shell serves as a proxy for road-salt pollution. We expected higher [Na/Ca]shell in winter and spring. However, high-resolution [Na/Ca]shell analyses along the growth axis of one shell did not reveal any clear subannual patterns, which could be the result of shell growth cessation in winter and/or during periods of high stream sodium concentrations. Therefore, bulk [Na/Ca]shell analysis from multiple shells can be used as a proxy of large changes in stream sodium concentrations, but high-resolution variations in stream sodium concentrations do not seem to be recorded in the shells. PMID:25418687

National-Scale Air Quality Data Assessment: Initial Findings from the Near-Road NO2 Monitoring Program

NASA Astrophysics Data System (ADS)

DeWinter, J. L.

2015-12-01

In 2010, the U.S. Environmental Protection Agency (EPA) revised the National Ambient Air Quality Standards (NAAQS) for nitrogen dioxide (NO2) to include a primary health-based standard for hourly NO2. NO2 is a reactive gas that is emitted from motor vehicles, such as cars, trucks, and off-road equipment, as well as non-mobile sources, and is known to adversely affect human respiratory health. In conjunction with the NAAQS revision, EPA has mandated air quality monitoring next to selected major roadways throughout the United States that are in large urban areas where peak hourly NO2 concentrations are expected. Monitoring began in phases during 2012-2015 and included nitrogen dioxide (NO2), carbon monoxide (CO), and particulate matter smaller than 2.5 microns (PM2.5) at 40 monitoring sites nationwide. We conducted a national-scale review of near-road air pollutant concentrations, identified areas where high concentrations of NO2, PM2.5, and CO occurred, and evaluated how concentrations varied by factors such as location, distance to roadway, fleet mix characteristics, and traffic volume. We present the findings from our national near-road data assessment for the 2014 monitoring year.

The environmental history and probable future of fluorocarbon-11

NASA Astrophysics Data System (ADS)

Khalil, M. A. K.; Rasmussen, R. A.

1993-12-01

The atmospheric concentration of fluorocarbon 11 (F-11) has increased steadily since it was first put into commercial use in the late 1930s and early 1940s. The observed trends, however, have two periods of dramatic declines. The first occurred around 1974, when trends started falling from their all time high of 13.8 pptv/yr down to around 7.8 pptv/yr (1 pptv = 10-12 parts by volume) in 1982. This decline occurred at first, probably, because of market conditions and later because of the ban in the United States on inessential uses of F-11, particularly in aerosol spray cans. In the meantime, other uses of F-11, such as blowing foams, increased, causing an increasing trend once again until around 1987, when the atmospheric trends reached 11 pptv/yr (measured 1986-1988, inclusive). After this time, however, the trends have fallen dramatically and are now only 4.6 pptv/yr (measured 1990-1992) and even lower in the middle northern latitudes (about 2 pptv/yr). The recent decline of trend is attributed to the effect of the Montreal Protocol and subsequent agreements that are designed to ban worldwide production before the turn of this century. The atmospheric trends reflect estimated emissions, which reached highest values in 1974 (340-355 Gg/yr; 1 Gg = 109g) and again in 1988 (314-380 Gg/yr). The observed concentrations and trends agree extremely well with those calculated from independent estimates of emissions from the various sources. Atmospheric concentrations of F-11 are calculated from a mass balance theory involving seven reservoirs and their interactions. Three of the reservoirs are at the Earth's surface arising from the uses of F-11 (quick-release applications such as open cell foams and aerosols, nonhermetically sealed refrigeration, and rigid polyurethane foams). We estimate that of the 9150 Gg of F-11 that have been produced throughout its history, at present about 1040 Gg are tied up in rigid foams (90 Gg and 24 Gg are tied up in refrigeration and quick-release applications, respectively). There are four environmental reservoirs (deep oceans, the ocean mixed layer, the troposphere, and the stratosphere). F-11 is dynamically exchanged between these reservoirs and is destroyed principally by photolysis in the stratosphere and by soils at the Earth's surface. At present there are about 5360 Gg in the troposphere, 740 Gg in the stratosphere, and small amounts in the oceans (27 Gg and 6 Gg in the mixed layer and deep oceans, respectively). About 81% of the 9 Tg of F-11 produced is still in the surface or environmental reservoirs (1 Tg = 1012g). The future concentrations of F-11 depend on leakage rates from the surface reservoirs and the atmospheric lifetime. It seems that concentrations are not likely to reach the peaks expected earlier and are likely to decline faster than previously thought. The peak concentration is expected to be about 275 pptv and may occur within the next 2 to 3 years. This abstract, the figures, and their captions form a self-contained condensed description of our results.

Short-term effect of nutrient availability and rainfall distribution on biomass production and leaf nutrient content of savanna tree species.

PubMed

Barbosa, Eduardo R M; Tomlinson, Kyle W; Carvalheiro, Luísa G; Kirkman, Kevin; de Bie, Steven; Prins, Herbert H T; van Langevelde, Frank

2014-01-01

Changes in land use may lead to increased soil nutrient levels in many ecosystems (e.g. due to intensification of agricultural fertilizer use). Plant species differ widely in their response to differences in soil nutrients, and for savannas it is uncertain how this nutrient enrichment will affect plant community dynamics. We set up a large controlled short-term experiment in a semi-arid savanna to test how water supply (even water supply vs. natural rainfall) and nutrient availability (no fertilisation vs. fertilisation) affects seedlings' above-ground biomass production and leaf-nutrient concentrations (N, P and K) of broad-leafed and fine-leafed tree species. Contrary to expectations, neither changes in water supply nor changes in soil nutrient level affected biomass production of the studied species. By contrast, leaf-nutrient concentration did change significantly. Under regular water supply, soil nutrient addition increased the leaf phosphorus concentration of both fine-leafed and broad-leafed species. However, under uneven water supply, leaf nitrogen and phosphorus concentration declined with soil nutrient supply, this effect being more accentuated in broad-leafed species. Leaf potassium concentration of broad-leafed species was lower when growing under constant water supply, especially when no NPK fertilizer was applied. We found that changes in environmental factors can affect leaf quality, indicating a potential interactive effect between land-use changes and environmental changes on savanna vegetation: under more uneven rainfall patterns within the growing season, leaf quality of tree seedlings for a number of species can change as a response to changes in nutrient levels, even if overall plant biomass does not change. Such changes might affect herbivore pressure on trees and thus savanna plant community dynamics. Although longer term experiments would be essential to test such potential effects of eutrophication via changes in leaf nutrient concentration, our findings provide important insights that can help guide management plans that aim to preserve savanna biodiversity.

[Development of technologies of population health management in Kazakhstan based on an integrated assessment of the combined exposure to environmental factors].

PubMed

Sraubaev, E N; Serik, B

2013-01-01

At present there is overdue necessity of an integral approach to the assessment of health status and the impact of environmental factors on it, in the development of science-based management decisions and programs on improvement of the health status of the population of Kazakhstan and in the increase in life expectancy from the birth and healthy life expectancy. The purpose of the proposed program--improving health and increasing life expectancy from the birth and healthy life expectancy of the population of Kazakhstan. Based on a meta-analysis to justify the target age group in which an implementation of complex of preventive measures will increase both the life expectancy from the birth and healthy life expectancy, to perform a comprehensive health screening for the basic classes of diseases and behavioral characteristics of the target group in the course of a multicentre studies to give a comprehensive hygienic characteristics of the ecological status of the studied regions and to develop the Health Passport of the region, to develop a model of the combined effects of environmental factors on health; to create a theoretical model for the calculation of life expectancy from the birth and healthy life expectancy, taking into account the limits of modifiability of factors that affect them, and justify a comprehensive program of management decisions on modification of factors, to carry out pilot studies on the development and validation technological (managemental) solutions to control modifiable factors that affect life expectancy from the birth and healthy life expectancy.

Humidity-Induced Photoluminescence Hysteresis in Variable Cs/Br Ratio Hybrid Perovskites.

PubMed

Howard, John M; Tennyson, Elizabeth M; Barik, Sabyasachi; Szostak, Rodrigo; Waks, Edo; Toney, Michael F; Nogueira, Ana F; Neves, Bernardo R A; Leite, Marina S

2018-06-21

Hybrid organic-inorganic perovskites containing Cs are a promising new material for light-absorbing and light-emitting optoelectronics. However, the impact of environmental conditions on their optical properties is not fully understood. Here, we elucidate and quantify the influence of distinct humidity levels on the charge carrier recombination in Cs x FA 1- x Pb(I y Br 1- y ) 3 perovskites. Using in situ environmental photoluminescence (PL), we temporally and spectrally resolve light emission within a loop of critical relative humidity (rH) levels. Our measurements show that exposure up to 35% rH increases the PL emission for all Cs (10-17%) and Br (17-38%) concentrations investigated here. Spectrally, samples with larger Br concentrations exhibit PL redshift at higher humidity levels, revealing water-driven halide segregation. The compositions considered present hysteresis in their PL intensity upon returning to a low-moisture environment due to partially reversible hydration of the perovskites. Our findings demonstrate that the Cs/Br ratio strongly influences both the spectral stability and extent of light emission hysteresis. We expect our method to become standard when testing the stability of emerging perovskites, including lead-free options, and to be combined with other parameters known for affecting material degradation, e.g., oxygen and temperature.

Atmospheric concentrations of polybrominated diphenyl ethers at near-source sites.

PubMed

Cahill, Thomas M; Groskova, Danka; Charles, M Judith; Sanborn, James R; Denison, Michael S; Baker, Lynton

2007-09-15

Concentrations of polybrominated diphenyl ethers (PBDEs) were determined in air samples from near suspected sources, namely an indoors computer laboratory, indoors and outdoors at an electronics recycling facility, and outdoors at an automotive shredding and metal recycling facility. The results showed that (1) PBDE concentrations in the computer laboratorywere higherwith computers on compared with the computers off, (2) indoor concentrations at an electronics recycling facility were as high as 650,000 pg/m3 for decabromodiphenyl ether (PBDE 209), and (3) PBDE 209 concentrations were up to 1900 pg/m3 at the downwind fenceline at an automotive shredding/metal recycling facility. The inhalation exposure estimates for all the sites were typically below 110 pg/kg/day with the exception of the indoor air samples adjacent to the electronics shredding equipment, which gave exposure estimates upward of 40,000 pg/kg/day. Although there were elevated inhalation exposures at the three source sites, the exposure was not expected to cause adverse health effects based on the lowest reference dose (RfD) currently in the Integrated Risk Information System (IRIS), although these RfD values are currently being re-evaluated by the U.S. Environmental Protection Agency. More research is needed on the potential health effects of PBDEs.

Assessment of peracetic acid disinfected effluents by microbiotests.

PubMed

Antonelli, M; Mezzanotte, V; Panouillères, M

2009-09-01

Bioassays were performed by commercially available kits on peracetic acid (PAA) solutions, at different concentrations, and on secondary effluents (from two different wastewater treatment plants) after disinfection at bench-scale, considering both samples containing residual active PAA and the same samples where residual PAA was quenched. Four indicator organisms were used: Vibrio fischeri, Thamnocephalus platyurus, Daphnia magna, and Selenastrum capricornutum. The experiments lead to conclude that Thamnocephalus platyurus is a very sensitive organism, probably not adequate to perform a reliable toxicity assessment of effluents for monitoring purposes. The presence of specific organic compounds deriving from human metabolism and urban pollution, even at very low concentrations, can affect the results of bioassays, especially those performed on Vibrio fischeri. PAA is toxic for bacteria and crustaceans even at concentrations lower than the ones commonly used in wastewater disinfection (2-5 mg/L), while its effect on algae is smaller. The toxic effect on bacteria was expected, as PAA is used for disinfection, but its possible influence on biological processes in the receiving aquatic environment should be considered. Toxicity on crustaceans would confirm the fact that discharging disinfected effluents could raise some environmental problems.

Mixture toxicity in the marine environment: Model development and evidence for synergism at environmental concentrations.

PubMed

Deruytter, David; Baert, Jan M; Nevejan, Nancy; De Schamphelaere, Karel A C; Janssen, Colin R

2017-12-01

Little is known about the effect of metal mixtures on marine organisms, especially after exposure to environmentally realistic concentrations. This information is, however, required to evaluate the need to include mixtures in future environmental risk assessment procedures. We assessed the effect of copper (Cu)-Nickel (Ni) binary mixtures on Mytilus edulis larval development using a full factorial design that included environmentally relevant metal concentrations and ratios. The reproducibility of the results was assessed by repeating this experiment 5 times. The observed mixture effects were compared with the effects predicted with the concentration addition model. Deviations from the concentration addition model were estimated using a Markov chain Monte-Carlo algorithm. This enabled the accurate estimation of the deviations and their uncertainty. The results demonstrated reproducibly that the type of interaction-synergism or antagonism-mainly depended on the Ni concentration. Antagonism was observed at high Ni concentrations, whereas synergism occurred at Ni concentrations as low as 4.9 μg Ni/L. This low (and realistic) Ni concentration was 1% of the median effective concentration (EC50) of Ni or 57% of the Ni predicted-no-effect concentration (PNEC) in the European Union environmental risk assessment. It is concluded that results from mixture studies should not be extrapolated to concentrations or ratios other than those investigated and that significant mixture interactions can occur at environmentally realistic concentrations. This should be accounted for in (marine) environmental risk assessment of metals. Environ Toxicol Chem 2017;36:3471-3479. © 2017 SETAC. © 2017 SETAC.

Postindustrialization and Environmental Quality: An Empirical Analysis of the Environmental State

ERIC Educational Resources Information Center

Fisher, Dana R.; Freudenburg, William R.

2004-01-01

Existing sociological analyses express differing expectations about state control over economic actors and the political feasibility of environmental regulation. Recent literature on the environmental state sees environmental protection as becoming a basic responsibility of postindustrial states, with economic actors no longer having the autonomy…

Long-Term Exposure to Environmental Concentrations of the Pharmaceutical Ethynylestradiol Causes Reproductive Failure in Fish

PubMed Central

Nash, Jon P.; Kime, David E.; Van der Ven, Leo T. M.; Wester, Piet W.; Brion, François; Maack, Gerd; Stahlschmidt-Allner, Petra; Tyler, Charles R.

2004-01-01

Heightened concern over endocrine-disrupting chemicals is driven by the hypothesis that they could reduce reproductive success and affect wildlife populations, but there is little evidence for this expectation. The pharmaceutical ethynylestradiol (EE2) is a potent endocrine modulator and is present in the aquatic environment at biologically active concentrations. To investigate impacts on reproductive success and mechanisms of disruption, we exposed breeding populations (n = 12) of zebrafish (Danio rerio) over multiple generations to environmentally relevant concentrations of EE2. Life-long exposure to 5 ng/L EE2 in the F1 generation caused a 56% reduction in fecundity and complete population failure with no fertilization. Conversely, the same level of exposure for up to 40 days in mature adults in the parental F0 generation had no impact on reproductive success. Infertility in the F1 generation after life-long exposure to 5 ng/L EE2 was due to disturbed sexual differentiation, with males having no functional testes and either undifferentiated or inter-sex gonads. These F1 males also showed a reduced vitellogenic response when compared with F0 males, indicating an acclimation to EE2 exposure. Depuration studies found only a partial recovery in reproductive capacity after 5 months. Significantly, even though the F1 males lacked functional testes, they showed male-pattern reproductive behavior, inducing the spawning act and competing with healthy males to disrupt fertilization. Endocrine disruption is therefore likely to affect breeding dynamics and reproductive success in group-spawning fish. Our findings raise major concerns about the population-level impacts for wildlife of long-term exposure to low concentrations of estrogenic endocrine disruptors. PMID:15579420

Seasonal variation of endocrine disrupting compounds, pharmaceuticals and personal care products in wastewater treatment plants.

PubMed

Yu, Yong; Wu, Laosheng; Chang, Andrew C

2013-01-01

The occurrence of 14 endocrine disrupting compounds (EDCs), pharmaceuticals and personal care products (PPCPs) in influents, effluents and sludge from five wastewater treatment plants (WWTPs) in southern California was studied in winter and summer. All 14 compounds were detected in influent samples from the five WWTPs except for estrone. Paracetamol, naproxen and ibuprofen were the dominant compounds, with mean concentrations of 41.7, 35.7 and 22.3 μg/L, respectively. The treatment removal efficiency for most compounds was more than 90% and concentrations in the effluents were relatively low. Seasonal variation of the compounds' concentration in the wastewater was significant: the total concentration of each compound in the wastewater was higher in winter than in summer, which is attributed to more human consumption of pharmaceuticals during winter and faster degradation of the compounds in summer. The highest concentrations of triclosan and octylphenol were detected in sewage sludge, with mean concentrations of 1505 and 1179 ng/g, respectively. Risk quotients (RQs), expressed as the ratios of environmental concentrations and the predicted no-effect concentrations (PNEC), were less than unity for all the compounds except for estrone in the effluents, indicating no immediate ecological risk is expected. However, RQs were higher than unity for 2 EDCs (estrone and octylphenol) and carbamazepine in sludge samples, indicating a significant ecotoxicological risk to human health. Therefore, appropriate treatment of sewage sludge is required before its application. Copyright © 2012 Elsevier B.V. All rights reserved.

Selective pressure of antibiotic pollution on bacteria of importance to public health.

PubMed

Tello, Alfredo; Austin, Brian; Telfer, Trevor C

2012-08-01

Many bacteria of clinical importance survive and may grow in different environments. Antibiotic pollution may exert on them a selective pressure leading to an increase in the prevalence of resistance. In this study we sought to determine whether environmental concentrations of antibiotics and concentrations representing action limits used in environmental risk assessment may exert a selective pressure on clinically relevant bacteria in the environment. We used bacterial inhibition as an assessment end point to link antibiotic selective pressures to the prevalence of resistance in bacterial populations. Species sensitivity distributions were derived for three antibiotics by fitting log-logistic models to end points calculated from minimum inhibitory concentration (MIC) distributions based on worldwide data collated by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). To place bacteria represented in these distributions in a broader context, we performed a brief phylogenetic analysis. The potentially affected fraction of bacterial genera at measured environmental concentrations of antibiotics and environmental risk assessment action limits was used as a proxy for antibiotic selective pressure. Measured environmental concentrations and environmental risk assessment action limits were also directly compared to wild-type cut-off values. The potentially affected fraction of bacterial genera estimated based on antibiotic concentrations measured in water environments is ≤ 7%. We estimated that measured environmental concentrations in river sediments, swine feces lagoons, liquid manure, and farmed soil inhibit wild-type populations in up to 60%, 92%, 100%, and 30% of bacterial genera, respectively. At concentrations used as action limits in environmental risk assessment, erythromycin and ciprofloxacin were estimated to inhibit wild-type populations in up to 25% and 76% of bacterial genera. Measured environmental concentrations of antibiotics, as well as concentrations representing environmental risk assessment action limits, are high enough to exert a selective pressure on clinically relevant bacteria that may lead to an increase in the prevalence of resistance.

Impact of Beaver Pond Colonization History on Methylmercury Concentrations in Surface Water.

PubMed

Levanoni, Oded; Bishop, Kevin; Mckie, Brendan G; Hartman, Göran; Eklöf, Karin; Ecke, Frauke

2015-11-03

Elevated concentrations of methylmercury (MeHg) in freshwater ecosystems are of major environmental concern in large parts of the northern hemisphere. Beaver ponds have been identified as a potentially important source of MeHg. The role of beavers might be especially pronounced in large parts of Europe, where beaver populations have expanded rapidly following near-extirpation. This study evaluates the role of the age and colonization history (encompassing patterns of use and reuse) of ponds constructed by the Eurasian beaver Castor fiber in regulating MeHg concentrations in Swedish streams. In 12 beaver systems located in three regions, we quantified MeHg concentrations together with other relevant parameters on five occasions per year in 2012-2013. Five were pioneer systems, inundated for the first time since beaver extirpation, and seven were recolonized, with dams reconstructed by newly recolonizing beavers. MeHg concentrations in pioneer but not in recolonized beaver systems were up to 3.5 fold higher downstream than upstream of the ponds, and varied between seasons and years. Our results show that pioneer inundation by beavers can increase MeHg concentrations in streams, but that this effect is negligible when dams are reconstructed on previously used ponds. We therefore expect that the recovery and expansion of beavers in the boreal system will only have a transitional effect on MeHg in the environment.

NEW COLUMN SEPARATION METHOD FOR EMERGENCY URINE SAMPLES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maxwell, S; Brian Culligan, B

2007-08-28

The Savannah River Site Environmental Bioassay Lab participated in the 2007 NRIP Emergency Response program administered by the National Institute for Standards and Technology (NIST) in May, 2007. A new rapid column separation method was applied directly to the NRIP 2007 emergency urine samples, with only minimal sample preparation to reduce preparation time. Calcium phosphate precipitation, previously used to pre-concentrate actinides and Sr-90 in NRIP 2006 urine and water samples, was not used for the NRIP 2007 urine samples. Instead, the raw urine was acidified and passed directly through the stacked resin columns (TEVA+TRU+SR Resins) to separate the actinides andmore » strontium from the NRIP urine samples more quickly. This improvement reduced sample preparation time for the NRIP 2007 emergency urine analyses significantly. This approach works well for small volume urine samples expected during an emergency response event. Based on initial feedback from NIST, the SRS Environmental Bioassay Lab had the most rapid analysis times for actinides and strontium-90 analyses for NRIP 2007 urine samples.« less

Vulnerability to changes in malaria transmission due to climate change in West Africa

NASA Astrophysics Data System (ADS)

Yamana, T. K.; Eltahir, E. A.

2012-12-01

Malaria transmission in West Africa is strongly tied to climate; temperature affects the development rate of the malaria parasite, as well as the survival of the mosquitoes that transmit the disease, and rainfall is tied to mosquito abundance, as the vector lays its eggs in rain-fed water pools. As a result, the environmental suitability for malaria transmission in this region is expected to change as temperatures rise and rainfall patterns are altered. The vulnerability to changes in transmission varies throughout West Africa. Areas where malaria prevalence is already very high will be less sensitive to changes in transmission. Increases in environmental suitability for malaria transmission in the most arid regions may still be insufficient to allow sustained transmission. However, areas were malaria transmission currently occurs at low levels are expected to be the most sensitive to changes in environmental suitability for transmission. Here, we use data on current environment and malaria transmission rates to highlight areas in West Africa that we expect to be most vulnerable to an increase in malaria under certain climate conditions. We then analyze climate predictions from global climate models in vulnerable areas, and make predictions for the expected change in environmental suitability for malaria transmission using the Hydrology, Entomology and Malaria Transmission Simulator (HYDREMATS), a mechanistic model developed to simulate village-scale response of malaria transmission to environmental variables in West Africa.

Predicted persistence and response times of linear and cyclic volatile methylsiloxanes in global and local environments.

PubMed

Kim, Jaeshin; Mackay, Donald; Whelan, Michael John

2018-03-01

We investigated the response times of eight volatile methylsiloxanes (VMSs) in environmental systems at different scales from local to global, with a particular focus on overall loss rates after cessation of emissions. In part, this is driven by proposals to restrict the use of some of these compounds in certain products in Europe. The GloboPOP model estimated low absolute Arctic Contamination Potentials for all VMSs and rapid response times in all media except sediment. VMSs are predicted to be distributed predominantly in air where they react with OH radicals, leading to short response times. After cessation of emissions VMSs concentrations in the environment are expected to decrease rapidly from current levels. Response times in specific water and sediment systems were evaluated using a dynamic QWASI model. Response times were sensitive to both physico-chemical properties and environmental characteristics. Degradation was predicted to play the most important role in determining response times in water and sediment. In the case of the lowest molecular weight VMSs such as L2 and D3, response times were essentially independent of environmental characteristics due to fast hydrolysis in water and sediment. However, response times for the other VMSs are system-specific. They are relatively short in shallow water bodies but increase with depth due to the diminishing role of volatilization on concentration change as volume to surface area ratio increases. In sediment, degradation and resuspension rates also contribute most to the response times. The estimated response times for local environments are useful for planning future monitoring programs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Commercial silicate phosphate sequestration and desorption leads to a gradual decline of aquatic systems.

PubMed

Svatos, Karl B W

2018-02-01

Laboratory desorption behaviour, function and elemental composition of commercially marketed silicate minerals used to sequester phosphorus pollution as well as Zeolite, Smectite, and Kaolinite were determined to see whether their use by environmental scientists and water managers in eutrophic waterways has the potential to contribute to longer-term environmental impacts. As expected, lower phosphorus concentrations were observed, following treatment. However, data relating to desorption, environmental fate and bioavailability of phospho-silicate complexes (especially those containing rare earth elements) appear to be underrepresented in product testing and trial publications. Analysis of desorption of phosphate (P) was > 5 μg[P]/L for all three non-commercial samples and 0 > μg[P]/L > 5 for all commercial silicates for a range of concentrations from 0 to 300 μg[P]/L. Based on a review of bioaccumulation data specific to the endangered Cherax tenuimanus (Hairy Marron) and other endemic species, this is significant considering anything > 20 μg[La]/L is potentially lethal to the hairy marron, other crustaceans and even other phyla. Where prokaryotic and eukaryotic effects are underreported, this represents a significant challenge. Especially where product protocols recommend continual reapplication, this is significant because both the forward and reverse reactions are equally important. The users of silicate minerals in water columns should accept the dynamic nature of the process and pay equal attention to both adsorption and desorption because desorption behaviour is an inherent trait. Even if broader desorption experimentation is difficult, expensive and time-consuming, it is a critical consideration nonetheless.

Photocatalytic effects of titanium dioxide nanoparticles on aquatic organisms-Current knowledge and suggestions for future research.

PubMed

Haynes, Vena N; Ward, J Evan; Russell, Brandon J; Agrios, Alexander G

2017-04-01

Nanoparticles are entering natural systems through product usage, industrial waste and post-consumer material degradation. As the production of nanoparticles is expected to increase in the next decade, so too are predicted environmental loads. Engineered metal-oxide nanomaterials, such as titanium dioxide, are known for their photocatalytic capabilities. When these nanoparticles are exposed to ultraviolet radiation in the environment, however, they can produce radicals that are harmful to aquatic organisms. There have been a number of studies that have reported the toxicity of titanium dioxide nanoparticles in the absence of light. An increasing number of studies are assessing the interactive effects of nanoparticles and ultraviolet light. However, most of these studies neglect environmentally-relevant experimental conditions. For example, researchers are using nanoparticle concentrations and light intensities that are too high for natural systems, and are ignoring water constituents that can alter the light field. The purpose of this review is to summarize the current knowledge of the photocatalytic effects of TiO 2 nanoparticles on aquatic organisms, discuss the limitations of these studies, and outline environmentally-relevant factors that need to be considered in future experiments. Copyright © 2017 Elsevier B.V. All rights reserved.

Integrated fate modeling for exposure assessment of produced water on the Sable Island Bank (Scotian shelf, Canada).

PubMed

Berry, Jody A; Wells, Peter G

2004-10-01

Produced water is the largest waste discharge from the production phase of oil and gas wells. Produced water is a mixture of reservoir formation water and production chemicals from the separation process. This creates a chemical mixture that has several components of toxic concern, ranging from heavy metals to soluble hydrocarbons. Analysis of potential environmental effects from produced water in the Sable Island Bank region (NS, Canada) was conducted using an integrated modeling approach according to the ecological risk assessment framework. A hydrodynamic dispersion model was used to describe the wastewater plume. A second fugacity-based model was used to describe the likely plume partitioning in the local environmental media of water, suspended sediment, biota, and sediment. Results from the integrated modeling showed that the soluble benzene and naphthalene components reach chronic no-effect concentration levels at a distance of 1.0 m from the discharge point. The partition modeling indicated that low persistence was expected because of advection forces caused by tidal currents for the Sable Island Bank system. The exposure assessment for the two soluble hydrocarbon components suggests that the risks of adverse environmental effects from produced water on Sable Island Bank are low.

Ground-Water Data for Indian Wells Valley, Kern, Inyo, and San Bernardino Counties, California, 1977-84

USGS Publications Warehouse

Berenbrock, Charles

1987-01-01

Ground water is the sole source of water in Indian Wells Valley. Since 1966, annual ground-water pumpage has exceeded estimates of mean annual recharge, and continued and increased stresses on the aquifer system of the valley are expected. In 1981 the U.S. Geological Survey began a 10-year program to develop a data base that could be used in evaluating future water-management alternatives for the valley. This report tabulates existing water-level and water-quality data in order to provide a basis for the design of a ground-water monitoring network for Indian Wells Valley. Water-levels were measured in 131 wells during 1977-84. About 62 percent of the wells that have water-level measurements spanning at least 3 years during the period 1977-84 show a net water-level decline; the decline in 23 percent of the wells is greater than 5 feet. Water-quality samples from 85 wells were analyzed for major dissolved constituents. At selected wells water samples were also analyzed for nutrients and trace metals. Seventy-nine of the wells sampled contained water with concentrations of one or more dissolved constituents that equaled or exceeded U.S. Environmental Protection Agency primary or secondary maximum contaminant levels for drinking water. Dissolved-solids concentrations, which ranged from 190 to 67,000 milligrams per liter, equaled or exceeded 500 milligrams per liter (the Environmental Protection Agency secondary maximum contaminant level) in 85 percent of the sampled wells and 1,000 milligrams per liter in 59 percent. Water samples collected in 1984 from eight wells near the industrial-waste ponds of the China Lake Naval Weapons Center were analyzed for the presence of organic compounds designated 'priority pollutants' by the U.S. Environmental Protection Agency. Priority pollutants were detected in three wells. Trichloroethylene, methylene chloride, vinyl chloride, and chloroform were identified; concentrations were less than 10 micrograms per liter except for trichloroethylene and chloroform, at 94 and 12 micrograms per liter, respectively. Trichloroethylene in one sample and vinyl chloride in another exceeded Environmental Protection Agency proposed maximum contaminant levels.

Niche and Neutral Processes Together Determine Diversity Loss in Response to Fertilization in an Alpine Meadow Community

PubMed Central

Li, Wei; Cheng, Ji-Min; Yu, Kai-Liang; Epstein, Howard E.; Du, Guo-Zhen

2015-01-01

Fertilization via nutrient deposition and agricultural inputs is one of the most important factors driving decreases in plant diversity. However, we still do not fully understand which processes (niche process or neutral process) are more important in leading to decreases in plant diversity caused by fertilization. A hypothesis-based approach was used to test the relative importance of niche versus neutral processes along a fertilization gradient in an alpine meadow community on the eastern Tibetan plateau, China. Niche overlap values were calculated for species biomass, and the null model was used to generate the values of niche overlap expected at random. A linear regression modeling was used to evaluate the relationship between functional traits (specific leaf area, leaf dry matter content, and leaf total nitrogen concentration) and species relative abundance. Our results demonstrated that observed niche overlap for species biomass was significantly higher than expected at lower fertilization gradients. Moreover, we also found a significantly negative correlation between species relative abundance and specific leaf area and leaf dry matter content, but a significantly positive correlation between relative abundance and leaf nitrogen concentration at lower fertilization gradients. However, these relationships were not significant at higher fertilization gradients. We concluded that community assembly is dynamic progression along the environmental gradients, and niche and neutral processes may together determine species diversity loss in response to fertilization. PMID:26280919

Determination of antifungal susceptibility patterns among the environmental isolates of Aspergillus fumigatus in Iran

PubMed Central

Mohammadi, Faezeh; Dehghan, Parvin; Nekoeian, Shahram; Hashemi, Seyed Jamal

2016-01-01

Background: In recent years, triazole-resistant environmental isolates of Aspergillus fumigatus have emerged in Europe and Asia. Azole resistance has been reported in patients who are treated with long-term azole therapy or exposure of the fungus spores to the azole fungicides used in agriculture. To date, a wide range of mutations in A. fumigatus have been described conferring azole-resistance, which commonly involves modifications in the cyp51A gene. We investigated antifungal susceptibility pattern of environmental isolates of A. fumigatus. Materials and Methods: In this study, 170 environmental samples collected from indoors surfaces of three hospitals in Iran. It was used β-tubulin gene to confirm the all of A. fumigatus isolates, which was identified by conventional methods. Furthermore, the antifungal susceptibility of itraconazole, voriconazole, and posaconazole was investigated using broth microdilution test, according to European Committee on Antimicrobial Susceptibility testing reference method. Results: From a total of 158 environmental molds fungi obtained from the hospitals, 58 isolates were identified as A. fumigatus by amplification of expected size of β-tubulin gene (~500 bp). In this study, in vitro antifungal susceptibility testing has shown that there were not high minimum inhibitory concentration values of triazole antifungals in all of the 58 environmental isolates of A. fumigatus. Conclusion: Our findings demonstrated that there was not azole-resistant among environmental isolates of A. fumigatus. Medical triazoles compounds have structural similarity with triazole fungicide compounds in agriculture, therefore, resistance development through exposure to triazole fungicide compounds in the environment is important but it sounds there is not a serious health problem in drug resistance in environmental isolates in Iran. PMID:27656605

Beyond the Limitations of Environmental Education in Japan

ERIC Educational Resources Information Center

Imamura, Mitsuyuki

2017-01-01

Environmental education has not spread as widely in Japan as expected and therefore has not had any significant impact on environmental problems, even though many educators and researchers have devoted themselves to environmental educational practice. Why is environmental education not popular in Japan, and what does this tell us? The purpose of…

Environmental risk assessment of paroxetine.

PubMed

Cunningham, Virginia L; Constable, David J C; Hannah, Robert E

2004-06-15

Paroxetine hydrochloride hemihydrate (the active ingredient in Paxil) is a pharmaceutical compound used for the treatment of depression, social anxiety disorder, obsessive compulsive disorder, panic disorder, and generalized anxiety disorder. Paroxetine (PA) is extensively metabolized in humans, with about 97% of the parent compound being excreted as metabolites through the urine and feces of patients. Therefore PA and metabolites have the potential to be discharged into wastewater treatment systems after therapeutic use. PA and its major human metabolite (PM) were investigated using studies designed to describe physical/chemical characteristics and determine their fate and effects in the aquatic environment. A significant portion of the PM entering a wastewater treatment plant would be expected to biodegrade given the higher activated sludge solids concentrations present in a typical wastewater treatment plant. The potential for direct photolysis of PM is also possible based on photolysis results for PA itself. These results provide strong support for expecting that PA and PM residuals will not persist in the aquatic environment after discharge from a wastewater treatment facility. This conclusion is also supported by the results of a USGS monitoring study, where no PM was detected in any of the samples at the 260 ng/L reporting limit. The results presented here also demonstrate the importance of understanding the human metabolism of a pharmaceutical so that the appropriate molecule(s) is used for fate and effects studies. In addition to the PA fate studies, PM was investigated using studies designed to determine potential environmental effects and a predicted no effect level (PNEC). The average measured activated sludge respiration inhibition value (EC50) for PM was 82 mg/L. The measured Microtox EC50 value was 33.0 mg/L, while the Daphnia magna EC50 value was 35.0 mg/L. The PNEC for PM was calculated to be 35.0 microg/L. Fate data were then used in a new watershed-based environmental risk assessment model, PhATE, to predict environmental concentrations (PECs). Comparison of the calculated PECs with the PNEC allows an assessment of potential environmental risk. Within the 1-99% of stream segments in the PhATE model, PEC values ranged from 0.003 to 100 ng/L. The risk assessment PEC/PNEC ratios ranged from approximately 3 x 10(-8) to approximately 3 x 10(-3), indicating a wide margin of safety, since a PEC/PNEC ratio <1 is generally considered to represent a low risk to the environment. In addition, Microtox studies carried out on PM biodegradation byproducts indicated no detectable residual toxicity. Any compounds in the environment as a result of the biodegradation of PM should be innocuous polar byproducts that should not exert any toxic effects.

Agricultural livelihoods in coastal Bangladesh under climate and environmental change--a model framework.

PubMed

Lázár, Attila N; Clarke, Derek; Adams, Helen; Akanda, Abdur Razzaque; Szabo, Sylvia; Nicholls, Robert J; Matthews, Zoe; Begum, Dilruba; Saleh, Abul Fazal M; Abedin, Md Anwarul; Payo, Andres; Streatfield, Peter Kim; Hutton, Craig; Mondal, M Shahjahan; Moslehuddin, Abu Zofar Md

2015-06-01

Coastal Bangladesh experiences significant poverty and hazards today and is highly vulnerable to climate and environmental change over the coming decades. Coastal stakeholders are demanding information to assist in the decision making processes, including simulation models to explore how different interventions, under different plausible future socio-economic and environmental scenarios, could alleviate environmental risks and promote development. Many existing simulation models neglect the complex interdependencies between the socio-economic and environmental system of coastal Bangladesh. Here an integrated approach has been proposed to develop a simulation model to support agriculture and poverty-based analysis and decision-making in coastal Bangladesh. In particular, we show how a simulation model of farmer's livelihoods at the household level can be achieved. An extended version of the FAO's CROPWAT agriculture model has been integrated with a downscaled regional demography model to simulate net agriculture profit. This is used together with a household income-expenses balance and a loans logical tree to simulate the evolution of food security indicators and poverty levels. Modelling identifies salinity and temperature stress as limiting factors to crop productivity and fertilisation due to atmospheric carbon dioxide concentrations as a reinforcing factor. The crop simulation results compare well with expected outcomes but also reveal some unexpected behaviours. For example, under current model assumptions, temperature is more important than salinity for crop production. The agriculture-based livelihood and poverty simulations highlight the critical significance of debt through informal and formal loans set at such levels as to persistently undermine the well-being of agriculture-dependent households. Simulations also indicate that progressive approaches to agriculture (i.e. diversification) might not provide the clear economic benefit from the perspective of pricing due to greater susceptibility to climate vagaries. The livelihood and poverty results highlight the importance of the holistic consideration of the human-nature system and the careful selection of poverty indicators. Although the simulation model at this stage contains the minimum elements required to simulate the complexity of farmer livelihood interactions in coastal Bangladesh, the crop and socio-economic findings compare well with expected behaviours. The presented integrated model is the first step to develop a holistic, transferable analytic method and tool for coastal Bangladesh.

Ambient concentrations of total suspended particulate matter and its elemental constituents at the wider area of the mining facilities of TVX Hellas in Chalkidiki, Greece.

PubMed

Gaidajis, George

2003-01-01

To assess ambient air quality at the wider area of TVX Hellas mining facilities, the Total Suspended Particulate matter (TSP) and its content in characteristic elements, i.e., As, Cd, Cu, Fe, Mn, Pb, Zn are being monitored for more than thirty months as part of the established Environmental Monitoring Program. High Volume air samplers equipped with Tissue Quartz filters were employed for the collection of TSP. Analyses were effected after digestion of the suspended particulate with an HNO3-HCl solution and determination of elemental concentrations with an Atomic Absorption Spectroscopy equipped with graphite furnace. The sampling stations were selected to record representatively the existing ambient air quality in the vicinity of the facilities and at remote sites not affected from industrial activities. Monitoring data indicated that the background TSP concentrations ranged from 5-60 microg/m3. Recorded TSP concentrations at the residential sites close to the facilities ranged between 20-100 microg/m3, indicating only a minimal influence from the mining and milling activities. Similar spatial variation was observed for the TSP constituents and specifically for Pb and Zn. To validate the monitoring procedures, a parallel sampling campaign took place with different High Volume samplers at days where low TSP concentrations were expected. The satisfactory agreement (+/- 11%) at low concentrations (50-100 microg/m3) clearly supported the reproducibility of the techniques employed specifically at the critical range of lower concentrations.

Evaluating the similarity of complex drinking-water disinfection by-product mixtures: overview of the issues.

PubMed

Rice, Glenn E; Teuschler, Linda K; Bull, Richard J; Simmons, Jane E; Feder, Paul I

2009-01-01

Humans are exposed daily to complex mixtures of environmental chemical contaminants, which arise as releases from sources such as engineering procedures, degradation processes, and emissions from mobile or stationary sources. When dose-response data are available for the actual environmental mixture to which individuals are exposed (i.e., the mixture of concern), these data provide the best information for dose-response assessment of the mixture. When suitable data on the mixture itself are not available, surrogate data might be used from a sufficiently similar mixture or a group of similar mixtures. Consequently, the determination of whether the mixture of concern is "sufficiently similar" to a tested mixture or a group of tested mixtures is central to the use of whole mixture methods. This article provides an overview for a series of companion articles whose purpose is to develop a set of biostatistical, chemical, and toxicological criteria and approaches for evaluating the similarity of drinking-water disinfection by-product (DBPs) complex mixtures. Together, the five articles in this series serve as a case study whose techniques will be relevant to assessing similarity for other classes of complex mixtures of environmental chemicals. Schenck et al. (2009) describe the chemistry and mutagenicity of a set of DBP mixtures concentrated from five different drinking-water treatment plants. Bull et al. (2009a, 2009b) describe how the variables that impact the formation of DBP affect the chemical composition and, subsequently, the expected toxicity of the mixture. Feder et al. (2009a, 2009b) evaluate the similarity of DBP mixture concentrates by applying two biostatistical approaches, principal components analysis, and a nonparametric "bootstrap" analysis. Important factors for determining sufficient similarity of DBP mixtures found in this research include disinfectant used; source water characteristics, including the concentrations of bromide and total organic carbon; concentrations and proportions of individual DBPs with known toxicity data on the same endpoint; magnitude of the unidentified fraction of total organic halides; similar toxicity outcomes for whole mixture testing (e.g., mutagenicity); and summary chemical measures such as total trihalomethanes, total haloacetic acids, total haloacetonitriles, and the levels of bromide incorporation in the DBP classes.

Detecting long-term temporal trends in sediment-bound trace metals from urbanised catchments.

PubMed

Sharley, David J; Sharp, Simon M; Bourgues, Sophie; Pettigrove, Vincent J

2016-12-01

The shift from rural lifestyles to urban living has dramatically altered the way humans interact and live across the globe. With over 50% of the world's populations living within cities, and significant increases expected over the next 50 years, it is critical that changes to social, economic and environmental sustainability of cities globally be implicit. Protecting and enhancing aquatic ecosystems, which provide important ecosystem services, is challenging. A number of factors influence pollutants in urban waterways including changes in land-use, impervious area and stormwater discharges, with sediment-bound pollution a major issue worldwide. This work aimed to investigate the spatial and temporal distribution of trace metals in freshwater sediments from six urbanised catchment over a 30-year period. It provides an estimate of pollution using a geoaccumulation index and examines possible toxicity using a probable effect concentration quotient (mPECq). Results showed significant temporal changes in metal concentrations over time, with lead generally decreasing in all but one of the sites, attributed to significant changes in environmental policies and the active elimination of lead products. Temporal changes in other metals were variable and likely dependent on site-specific factors. While it is likely that diffuse pollution is driving changes in zinc, for metals such as lead, chromium and copper, it is likely that watershed landuse and/or point sources are more important. The results clearly indicated that changes to watershed landuse, environmental policy and pollution abatement programs are all driving changes in sediment quality, highlighting the utility of long-term sediment monitoring for assessment of urban watershed condition. While this study has demonstrated the utility of detecting long-term changes in metal concentrations, this approach could easily be adapted to detect and assess future trends in other hydrophobic contaminants and emerging chemicals of concern, such as synthetic pyrethroids, providing essential information for the protection of catchment. Copyright © 2016 Elsevier Ltd. All rights reserved.

Assessing the risk associated with the presence of emerging organic contaminants in sludge-amended soil: A country-level analysis.

PubMed

Thomaidi, Vasiliki S; Stasinakis, Athanasios S; Borova, Viola L; Thomaidis, Nikolaos S

2016-04-01

Greece was used as case study and the environmental risk associated with the existence of 99 emerging organic contaminants (EOCs) in sludge-amended soil was estimated using risk quotient (RQ) approach. Data on the concentration levels of EOCs in sewage sludge was collected after literature review. Chemical analyses were also conducted for 50 pharmaceuticals and illicit drugs in sludge samples from Athens Sewage Treatment Plant. Risk assessment was based on both terrestrial and aquatic acute toxicity data, using both the maximum and the average measured concentrations of the target compounds. EC50/LC50 values were collected through literature review or using the ECOSAR program in cases that experimental values were not available. Triclosan seems to pose an environmental risk on the soil environment, as its RQ values exceeded 1, both in terrestrial and aquatic toxicity data based risk assessment. Calculations based on aquatic toxicity data showed that another eleven compounds had RQs higher than 1, most of them belonging to the classes of synthetic phenolic compounds and siloxanes. Tetradecamethylhexasiloxane presented the highest RQ, while high RQs were also calculated for decamethylcyclopentasiloxane and caffeine. No environmental risk for the terrestrial environment is expected due to the individual action of illicit drugs, perfluorinated compounds and benzotriazoles. The sludge source and the day of sampling affected the estimated threat due to nonylphenolic compounds; however these factors did not affect the estimated risk for siloxanes, caffeine and ofloxacin. Calculation of RQ values for the mixture of EOCs, using either the maximum or the average concentrations, far exceeded 1 (253 and 209, respectively), indicating a presumable threat for the terrestrial environment due to the baseline toxicity of these compounds. Countries that reuse sludge for agricultural purposes should include specific EOCs in national monitoring campaigns and study more thoroughly on their effects to the terrestrial environment. Copyright © 2016 Elsevier B.V. All rights reserved.

Occurrence and estrogenic potency of eight bisphenol analogs in sewage sludge from the U.S. EPA targeted national sewage sludge survey.

PubMed

Yu, Xiaohua; Xue, Jingchuan; Yao, Hong; Wu, Qian; Venkatesan, Arjun K; Halden, Rolf U; Kannan, Kurunthachalam

2015-12-15

As health concerns over bisphenol A (BPA) in consumer products are mounting, this weak estrogen mimicking compound is gradually being replaced with structural analogs, whose environmental occurrence and estrogen risks are not well understood yet. We used high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to determine the concentrations of eight bisphenol analogs in 76 sewage sludge samples collected by the U.S. Environmental Protection Agency (EPA) in 2006/2007 from 74 wastewater treatment plants (WWTPs) in 35 states. Bisphenols were detected at the following concentration ranges (ng/g dry weight) and detection frequencies: BPA (6.5-4700; 100%); bisphenol S (BPS; <1.79-1480; 84%); bisphenol F (BPF; <1.79-242; 68%); bisphenol AF (BPAF; <1.79-72.2; 46%); bisphenol P (BPP; <1.79-6.42; <5%), bisphenol B (BPB; <1.79-5.60; <5%), and bisphenol Z (BPZ; <1.79--66.7; <5%). Bisphenol AP (BPAP) was not detected in any of the samples (<1.79 ng/g dw). Concentrations of BPA in sewage sludge were an order of magnitude higher than those reported in China but similar to those in Germany. The calculated 17β-estradiol equivalents (E2EQ) of bisphenols present in sludge samples were 7.74 (0.26-90.5) pg/g dw, which were three orders of magnitude lower than the estrogenic activity contributed by natural estrogens present in the sludge. The calculated mass loading of bisphenols through the disposal of sludge and wastewater was <0.02% of the total U.S. production. As the usage of BPA is expected to decline further, environmental emissions of BPS, BPF, and BPAF are likely to increase in the future. This study establishes baseline levels and estrogenic activity of diverse bisphenol analogs in sewage sludge. Copyright © 2015 Elsevier B.V. All rights reserved.

Nutrient Concentrations and Their Relations to the Biotic Integrity of Nonwadeable Rivers in Wisconsin

USGS Publications Warehouse

Robertson, Dale M.; Weigel, Brian M.; Graczyk, David J.

2008-01-01

Excessive nutrient [phosphorus (P) and nitrogen (N)] input from point and nonpoint sources is frequently associated with degraded water quality in streams and rivers. Point-source discharges of nutrients are fairly constant and are controlled by the U.S. Environmental Protection Agency's (USEPA) National Pollutant Discharge Elimination System. To reduce inputs from nonpoint sources, agricultural performance standards and regulations for croplands and livestock operations are being proposed by various States. In addition, the USEPA is establishing regionally based nutrient criteria that can be refined by each State to determine whether actions are needed to improve water quality. More confidence in the environmental benefits of the proposed performance standards and nutrient criteria would be possible with improved understanding of the biotic responses to a range of nutrient concentrations in different environmental settings. To achieve this general goal, the U.S. Geological Survey and the Wisconsin Department of Natural Resources collected data from 282 streams and rivers throughout Wisconsin during 2001 through 2003 to: (1) describe how nutrient concentrations and biotic-community structure differ throughout the State, (2) determine which environmental characteristics are most strongly related to the distribution of nutrient concentrations and biotic-community structure, (3) determine reference conditions for water quality and biotic indices for streams and rivers in the State, (4) determine how the biotic communities in streams and rivers in different areas of the State respond to differences in nutrient concentrations, (5) determine the best regionalization scheme to describe the patterns in reference conditions and the corresponding responses in water quality and the biotic communities (primarily for smaller streams), and (6) develop algorithms to estimate nutrient concentrations in streams and rivers from a combination of biotic indices. The ultimate goal of this study is to provide the information needed to guide the development of regionally based nutrient criteria for Wisconsin streams and rivers. In this report, data collected, primarily in 2003, from 42 nonwadeable rivers are used to describe nutrient concentrations and their relations to the biotic integrity of rivers in Wisconsin. In a separate report by Robertson and others (2006a), the data collected from 240 wadeable streams are used to describe these relations in streams in Wisconsin. Reference water-quality conditions for nonwadeable rivers were found to be similar throughout Wisconsin (approximately 0.035 milligrams per liter (mg/L) for total P (TP), 0.500 mg/L for total N (TN), 4 micrograms per liter for suspended chlorophyll a (SCHL), and greater than 110 centimeters for Secchi-tube depth (SD)). For each category of the biotic community (SCHL, macroinvertebrates, and fish), a few indices were more strongly related to differences in nutrient concentrations than were others. For the indices most strongly related to nutrient concentrations, reference conditions were obtained with a regression approach, from values corresponding to the worst 75th-percentile value from a subset of minimally impacted streams (streams having reference nutrient concentrations), and from the best 25th-percentile value of all the data. Concentrations of TP and TN in nonwadeable rivers increased as the percentage of agricultural land in the basin increased; these increases resulted in increased SCHL concentrations and decreased SDs. The responses in SDs and SCHL concentrations to changes in nutrient concentrations were similar throughout most of the State except in rivers in the southeastern part, where SCHL concentrations were lower than would be expected given their nutrient concentrations. Rivers in the southeastern part of the State had high concentrations of total suspended sediment compared to the SCHL concentrations. Many biotic indices responded to increases in nu

Pyrethroid sorption to Sacramento River suspended solids and bed sediments.

PubMed

Fojut, Tessa L; Young, Thomas M

2011-04-01

Sorption of pyrethroid insecticides to solid materials will typically dominate the fate and transport of these hydrophobic compounds in aquatic environments. Batch reactor isotherm experiments were performed with bifenthrin and λ-cyhalothrin with suspended material and bed sediment collected from the Sacramento River, California, USA. These batch reactor experiments were performed with low spiking concentrations and a long equilibration time (28 d) to be more relevant to environmental conditions. Sorption to suspended material and bed sediment was compared to examine the role of differential sorption between these phases in the environmental transport of pyrethroids. The equilibrium sorption data were fit to the Freundlich isotherm model and fit with r(2)  > 0.87 for all experiments. Freundlich exponents ranged from 0.72 ± 0.19 to 1.07 ± 0.050, indicating sorption nonlinearity for some of the experimental conditions and linearity for others over the concentration range tested. The Freundlich capacity factors were larger for the suspended solids than for the bed sediments, and the suspended material had a higher specific surface area and higher organic carbon content compared to the bed sediment. Calculated organic carbon-normalized distribution coefficients were larger than those previously reported in the literature, by approximately an order of magnitude, and ranged from 10(6.16) to 10(6.68) at an equilibrium aqueous concentration of 0.1 µg/L. Higher than expected sorption of pyrethroids to the tested materials may be explained by sorption to black carbon and/or mineral surfaces. Copyright © 2011 SETAC.

Environmental Controls on Mg/Ca in Neogloboquadrina incompta: A Core-Top Study From the Subpolar North Atlantic

NASA Astrophysics Data System (ADS)

Morley, Audrey; Babila, Tali L.; Wright, James; Ninnemann, Ulysses; Kleiven, Kikki; Irvali, Nil; Rosenthal, Yair

2017-12-01

Magnesium/calcium paleothermometry is an established tool for reconstructing past surface and deep-sea temperatures. However, our understanding of nonthermal environmental controls on the uptake of Mg into the calcitic lattice of foraminiferal tests remains limited. Here we present a combined analysis of multiple trace element/calcium ratios and stable isotope (δ18O and δ13C) geochemistry on the subpolar planktonic foraminifera Neogloboquadrina incompta to assess the validity of Mg/Ca as a proxy for surface ocean temperature. We identify small size-specific offsets in Mg/Ca and δ18Oc values for N. incompta that are consistent with depth habitat migration patterns throughout the life cycle of this species. Additionally, an assessment of nonthermal controls on Mg/Ca values reveals that (1) the presence of volcanic ash, (2) the addition of high-Mg abiotic overgrowths, and (3) ambient seawater carbonate chemistry can have a significant impact on the Mg/Ca-to-temperature relationship. For carbonate-ion concentrations of values > 200 μmol kg-1, we find that temperature exerts the dominant control on Mg/Ca values, while at values < 200 μmol kg-1 the carbonate-ion concentration of seawater increases the uptake of Mg, thereby resulting in higher-than-expected Mg/Ca values at low temperatures. We propose two independent correction schemes to remove the effects of volcanic ash and carbonate-ion concentration on Mg/Ca values in N. incompta within the calibration data set. Applying the corrections improves the fidelity of past ocean temperature reconstructions.

The trans-continental distributions of pentachlorophenol and pentachloroanisole in pine needles indicate separate origins.

PubMed

Kylin, Henrik; Svensson, Teresia; Jensen, Sören; Strachan, William M J; Franich, Robert; Bouwman, Hindrik

2017-10-01

The production and use of pentachlorophenol (PCP) was recently prohibited/restricted by the Stockholm Convention on persistent organic pollutants (POPs), but environmental data are few and of varying quality. We here present the first extensive dataset of the continent-wide (Eurasia and Canada) occurrence of PCP and its methylation product pentachloroanisole (PCA) in the environment, specifically in pine needles. The highest concentrations of PCP were found close to expected point sources, while PCA chiefly shows a northern and/or coastal distribution not correlating with PCP distribution. Although long-range transport and environmental methylation of PCP or formation from other precursors cannot be excluded, the distribution patterns suggest that such processes may not be the only source of PCA to remote regions and unknown sources should be sought. We suggest that natural sources, e.g., chlorination of organic matter in Boreal forest soils enhanced by chloride deposition from marine sources, should be investigated as a possible partial explanation of the observed distributions. The results show that neither PCA nor total PCP (ΣPCP = PCP + PCA) should be used to approximate the concentrations of PCP; PCP and PCA must be determined and quantified separately to understand their occurrence and fate in the environment. The background work shows that the accumulation of airborne POPs in plants is a complex process. The variations in life cycles and physiological adaptations have to be taken into account when using plants to evaluate the concentrations of POPs in remote areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

Quality of volatile organic compound data from groundwater and surface water for the National Water-Quality Assessment Program, October 1996–December 2008

USGS Publications Warehouse

Bender, David A.; Zogorski, John S.; Mueller, David K.; Rose, Donna L.; Martin, Jeffrey D.; Brenner, Cassandra K.

2011-01-01

This report describes the quality of volatile organic compound (VOC) data collected from October 1996 to December 2008 from groundwater and surface-water sites for the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program. The VOC data described were collected for three NAWQA site types: (1) domestic and public-supply wells, (2) monitoring wells, and (3) surface-water sites. Contamination bias, based on the 90-percent upper confidence limit (UCL) for the 90th percentile of concentrations in field blanks, was determined for VOC samples from the three site types. A way to express this bias is that there is 90-percent confidence that this amount of contamination would be exceeded in no more than 10 percent of all samples (including environmental samples) that were collected, processed, shipped, and analyzed in the same manner as the blank samples. This report also describes how important native water rinsing may be in decreasing carryover contamination, which could be affecting field blanks. The VOCs can be classified into four contamination categories on the basis of the 90-percent upper confidence limit (90-percent UCL) concentration distribution in field blanks. Contamination category 1 includes compounds that were not detected in any field blanks. Contamination category 2 includes VOCs that have a 90-percent UCL concentration distribution in field blanks that is about an order of magnitude lower than the concentration distribution of the environmental samples. Contamination category 3 includes VOCs that have a 90-percent UCL concentration distribution in field blanks that is within an order of magnitude of the distribution in environmental samples. Contamination category 4 includes VOCs that have a 90-percent UCL concentration distribution in field blanks that is at least an order of magnitude larger than the concentration distribution of the environmental samples. Fifty-four of the 87 VOCs analyzed in samples from domestic and public-supply wells were not detected in field blanks (contamination category 1), and 33 VOC were detected in field blanks. Ten of the 33 VOCs had a 90-percent UCL concentration distribution in field blanks that was at least an order of magnitude lower than the concentration distribution in environmental samples (contamination category 2). These 10 VOCs may have had some contamination bias associated with the environmental samples, but the potential contamination bias was negligible in comparison to the environmental data; therefore, the field blanks were assumed to be representative of the sources of contamination bias affecting the environmental samples for these 10 VOCs. Seven VOCs had a 90-percent UCL concentration distribution of the field blanks that was within an order of magnitude of the concentration distribution of the environmental samples (contamination category 3). Sixteen VOCs had a 90-percent UCL concentration distribution in the field blanks that was at least an order of magnitude greater than the concentration distribution of the environmental samples (contamination category 4). Field blanks for these 16 VOCs appear to be nonrepresentative of the sources of contamination bias affecting the environmental samples because of the larger concentration distributions (and sometimes higher frequency of detection) in field blanks than in environmental samples. Forty-three of the 87 VOCs analyzed in samples from monitoring wells were not detected in field blanks (contamination category 1), and 44 VOCs were detected in field blanks. Eight of the 44 VOCs had a 90-percent UCL concentration distribution in field blanks that was at least an order of magnitude lower than concentrations in environmental samples (contamination category 2). These eight VOCs may have had some contamination bias associated with the environmental samples, but the potential contamination bias was negligible in comparison to the environmental data; therefore, the field blanks were assumed to be representative. Seven VOCs had a 90-percent UCL concentration distribution in field blanks that was of the same order of magnitude as the concentration distribution of the environmental samples (contamination category 3). Twenty-nine VOCs had a 90-percent UCL concentration distribution in the field blanks that was an order of magnitude greater than the distribution of the environmental samples (contamination category 4). Field blanks for these 29 VOCs appear to be nonrepresentative of the sources of contamination bias to the environmental samples. Fifty-four of the 87 VOCs analyzed in surface-water samples were not detected in field blanks (category 1), and 33 VOC were detected in field blanks. Sixteen of the 33 VOCs had a 90-percent UCL concentration distribution in field blanks that was at least an order of magnitude lower than the concentration distribution in environmental samples (contamination category 2). These 16 VOCs may have had some contamination bias associated with the environmental samples, but the potential contamination bias was negligible in comparison to the environmental data; therefore, the field blanks were assumed to be representative. Ten VOCs had a 90-percent UCL concentration distribution in field blanks that was similar to the concentration distribution of environmental samples (contamination category 3). Seven VOCs had a 90-percent UCL concentration distribution in the field blanks that was greater than the concentration distribution in environmental samples (contamination category 4). Field-blank samples for these seven VOCs appear to be nonrepresentative of the sources of contamination bias to the environmental samples. The relation between the detection of a compound in field blanks and the detection in subsequent environmental samples appears to be minimal. The median minimum percent effectiveness of native water rinsing is about 79 percent for the 19 VOCs detected in more than 5 percent of field blanks from all three site types. The minimum percent effectiveness of native water rinsing (10 percent) was for toluene in surface-water samples, likely because of the large detection frequency of toluene in surface-water samples (about 79 percent) and in the associated field-blank samples (46.5 percent). The VOCs that were not detected in field blanks (contamination category 1) from the three site types can be considered free of contamination bias, and various interpretations for environmental samples, such as VOC detection frequency at multiple assessment levels and comparisons of concentrations to benchmarks, are not limited for these VOCs. A censoring level for making comparisons at different assessment levels among environmental samples could be applied to concentrations of 9 VOCs in samples from domestic and public-supply wells, 16 VOCs in samples from monitoring wells, and 9 VOCs in surface-water samples to account for potential low-level contamination bias associated with these selected VOCs. Bracketing the potential contamination by comparing the detection and concentration statistics with no censoring applied to the potential for contamination bias on the basis of the 90-percent UCL for the 90th-percentile concentrations in field blanks may be useful when comparisons to benchmarks are done in a study. The VOCs that were not detected in field blanks (contamination category 1) from the three site types can be considered free of contamination bias, and various interpretations for environmental samples, such as VOC detection frequency at multiple assessment levels and comparisons of concentrations to benchmarks, are not limited for these VOCs. A censoring level for making comparisons at different assessment levels among environmental samples could be applied to concentrations of 9 VOCs in samples from domestic and public-supply wells, 16 VOCs in samples from monitoring wells, and 9 VOCs in surface-water samples to account for potential low-level contamination bias associated with these selected VOCs. Bracketing the potential contamination by comparing the detection and concentration statistics with no censoring applied to the potential for contamination bias on the basis of the 90-percent UCL for the 90th-percentile concentrations in field blanks may be useful when comparisons to benchmarks are done in a study.

Multiple imputation for multivariate data with missing and below-threshold measurements: time-series concentrations of pollutants in the Arctic.

PubMed

Hopke, P K; Liu, C; Rubin, D B

2001-03-01

Many chemical and environmental data sets are complicated by the existence of fully missing values or censored values known to lie below detection thresholds. For example, week-long samples of airborne particulate matter were obtained at Alert, NWT, Canada, between 1980 and 1991, where some of the concentrations of 24 particulate constituents were coarsened in the sense of being either fully missing or below detection limits. To facilitate scientific analysis, it is appealing to create complete data by filling in missing values so that standard complete-data methods can be applied. We briefly review commonly used strategies for handling missing values and focus on the multiple-imputation approach, which generally leads to valid inferences when faced with missing data. Three statistical models are developed for multiply imputing the missing values of airborne particulate matter. We expect that these models are useful for creating multiple imputations in a variety of incomplete multivariate time series data sets.

Use of geostatistics for assessing the concentration of heavy metals in a stretch of the River Apodi-Mossoro (Rio Grande do Norte State, Brazil).

NASA Astrophysics Data System (ADS)

Bezerra, J. M.; Siqueira, G. M.; Montenegro, A. A. A.; Silva, P. C. M.; Batista, R. O.

2012-04-01

The objective of this study was to assess the environmental changes with respect to the concentration of heavy metals in the sediment contained a stretch of the River Apodi-Mossoró (Rio Grande do Norte State, Brazil), considering changes in land use and soil. The sediment samples were collected at 30 points in the bed Apodi- Mossoró River in a section with features urban-rural town of Mossoró. The concentration of heavy metals in the sediment was determined using composite samples of surface sediments from the bottom with a depth of 20 cm, according to the methodology of APHAAWWA-WPCF (1998), where he subsequently held to determine the presence and quantity of metal concentration total by the technique of atomic absorption spectrometry, and analyzed the following heavy metals: aluminum(Al), cádmium (Cd), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn). Data were analyzed using statistical and geostatistical. The geostatistical analysiswas performed by the construction of experimental semivariogramas self-assessment and adjustment by using the technique of Jack-kinifing. The elemento Cd was absent in the samples, which reduces the possibility of environmental contamination events. The average concentrations of the elements under study are within the limits proposed by the environmental legislation (National Environmental Council). However, for the elements Fe, Al and Mn no threshold values, because these are associated with the rocky material of geochemical origin. The elemento Fe had the highest range of values than the other, and all elements except for Zn and Cd showed the presence of outliers, suggesting the possibility that these points are listed as points liable to contribution by human activities. It was verified the presence of human influence, because the elements undergo an increase of concentration values from the point 11, which is located downstream of the urban bus consolidated. The experimental semivariogramas of elements Cu and Zn adjusted to the spherical model, while the elemen Fe was adjusted to the exponential model. The concentration of Mn is set to the Gaussian model, while the other elements (Al, Cr, Ni and Pb) showed pure nugget effect. The spatial variability of heavy metals analyzed in the study area has high spatial discontinuity, being influenced by the presence of human action, leading to the existence of trend in the semivariogram of the data of Al, Ni, Pb and Cr. Being derived values range from 350 m for Cu and Mn, Fe and 400 m to 425 m for Zn. It is recommended that future studies adopt a sampling grid with spacing less than 350 mand is expected to get a better response to the behavior of the spatial variability of the elements.

76 FR 7844 - Notice of Open Meeting of the Environmental Financial Advisory Board (EFAB)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-11

... environmental programs, projects, and activities. The purpose of the meeting is to hear from informed speakers... work projects under EFAB's current Strategic Action Agenda. Environmental Finance topics expected to be discussed include: Financing Clean Air Technology; Voluntary Environmental Improvement Bonds (VEIB)/Property...

In vitro screening of environmental chemicals for targeted testing prioritization: the ToxCast project.

PubMed

Judson, Richard S; Houck, Keith A; Kavlock, Robert J; Knudsen, Thomas B; Martin, Matthew T; Mortensen, Holly M; Reif, David M; Rotroff, Daniel M; Shah, Imran; Richard, Ann M; Dix, David J

2010-04-01

Chemical toxicity testing is being transformed by advances in biology and computer modeling, concerns over animal use, and the thousands of environmental chemicals lacking toxicity data. The U.S. Environmental Protection Agency's ToxCast program aims to address these concerns by screening and prioritizing chemicals for potential human toxicity using in vitro assays and in silico approaches. This project aims to evaluate the use of in vitro assays for understanding the types of molecular and pathway perturbations caused by environmental chemicals and to build initial prioritization models of in vivo toxicity. We tested 309 mostly pesticide active chemicals in 467 assays across nine technologies, including high-throughput cell-free assays and cell-based assays, in multiple human primary cells and cell lines plus rat primary hepatocytes. Both individual and composite scores for effects on genes and pathways were analyzed. Chemicals displayed a broad spectrum of activity at the molecular and pathway levels. We saw many expected interactions, including endocrine and xenobiotic metabolism enzyme activity. Chemicals ranged in promiscuity across pathways, from no activity to affecting dozens of pathways. We found a statistically significant inverse association between the number of pathways perturbed by a chemical at low in vitro concentrations and the lowest in vivo dose at which a chemical causes toxicity. We also found associations between a small set of in vitro assays and rodent liver lesion formation. This approach promises to provide meaningful data on the thousands of untested environmental chemicals and to guide targeted testing of environmental contaminants.

Evaluation of organic compounds and trace elements in Amazon Creek Basin, Oregon, September 1990

USGS Publications Warehouse

Rinella, F.A.

1993-01-01

Water and bottom sediment were collected from Amazon Creek, Oregon during a summer low-flow condition and analyzed for different classes of organic compounds, including many from the U.S. Environmental Protection Agency's priority pollutant list. Bottom sediment also was analyzed for trace elements typically associated with urban runoff. Trace-element concentrations in the less than 63 micrometer fraction of Amazon Creek bottom-sediment samples were compared with baseline concentrations (expected 95 percent confidence range) for soils from the Western United States and with concen- trations found in bottom sediment from the Willamette River Basin. Total-digestion concentrations of antimony, arsenic, cadmium, chromium, cobalt, copper, lead, manganese, mercury, nickel, silver, titanium, and zinc were enriched at some or all sites sampled. Whole-water samples from some sites contained concentrations of several chlorophenoxy-acid herbicides, the organophosphorus insecticide diazinon, and several semivolatile priority pollutants. Classes of compounds not detected in whole-water samples included carbamate insecticides, triazine and other nitrogen-containing herbicides, and purgeable organic compounds. Bottom-sediment samples contained many organochlorine compounds, including chlordane, DDT plus metabolites, dieldrin, endrin, heptachlor epoxide (a metabolite of heptachlor), and PCBs at some or all sites sampled. Twenty-four of 54 semivolatile compounds were detected in bottom- sediment samples at some or all sites sampled.

Effects of extracellular polymeric substances on the bioaccumulation of mercury and its toxicity toward the cyanobacterium Microcystis aeruginosa.

PubMed

Chen, Ho-Wen; Huang, Winn-Jung; Wu, Ting-Hsiang; Hon, Chen-Lin

2014-01-01

This investigation examines how extracellular polymeric substances (EPSs) and environmental factors affect the bioaccumulation and toxicity of inorganic mercury (+2 oxidation state, Hg(II)) using a culture of Microcystis aeruginosa, which dominates eutrophic reservoir populations. The identified EPSs were classified as carbohydrates and proteins. Evaluation of the bioaccumulation of Hg(II) in cells by multiple regression analysis reveals that the concentration of EPSs in filtrate, the initial concentration of Hg(II) in medium, and the culture age significantly affected the amount of Hg(II) accumulated. Composition profiles revealed that the concentrations of soluble carbohydrates were significantly higher in Hg(II)-accumulated cells than in the control ones. Preliminary results based on scanning electron microscopic (SEM) map investigations suggest that most of the Hg(II) was accumulated in the cytoplasm (intracellular). Additionally, the effective concentrations (EC50) of Hg(II) that inhibit the growth of M. aeruginosa were 38.6 μg L(-1) in the logarithmic phase and 17.5 μg L(-1) in the stationary phase. As expected, the production of more EPSs in the logarithmic phase typically implies higher EC50 values because EPSs may be regarded as a protective barrier of cells against an external Hg(II) load, enabling them to be less influenced by Hg(II).

Desorption of intrinsic cesium from smectite: inhibitive effects of clay particle organization on cesium desorption.

PubMed

Fukushi, Keisuke; Sakai, Haruka; Itono, Taeko; Tamura, Akihiro; Arai, Shoji

2014-09-16

Fine clay particles have functioned as transport media for radiocesium in terrestrial environments after nuclear accidents. Because radiocesium is expected to be retained in clay minerals by a cation-exchange reaction, ascertaining trace cesium desorption behavior in response to changing solution conditions is crucially important. This study systematically investigated the desorption behavior of intrinsic Cs (13 nmol/g) in well-characterized Na-montmorillonite in electrolyte solutions (NaCl, KCl, CaCl2, and MgCl2) under widely differing cation concentrations (0.2 mM to 0.2 M). Batch desorption experiments demonstrated that Cs(+) desorption was inhibited significantly in the presence of the environmental relevant concentrations of Ca(2+) and Mg(2+) (>0.5 mM) and high concentrations of K(+). The order of ability for Cs desorption was Na(+) = K(+) > Ca(2+) = Mg(2+) at the highest cation concentration (0.2 M), which is opposite to the theoretical prediction based on the cation-exchange selectivity. Laser diffraction grain-size analyses revealed that the inhibition of Cs(+) desorption coincided with the increase of the clay tactoid size. Results suggest that radiocesium in the dispersed fine clay particles adheres on the solid phase when the organization of swelling clay particles occurs because of changes in solution conditions caused by both natural processes and artificial treatments.

Effects of ten antibiotics on seed germination and root elongation in three plant species.

PubMed

Hillis, Derek G; Fletcher, James; Solomon, Keith R; Sibley, Paul K

2011-02-01

We applied a screening-level phytotoxicity assay to evaluate the effects of 10 antibiotics (at concentrations ranging from 1 to 10,000 μg/L) on germination and early plant growth using three plant species: lettuce (Lactuca sativa), alfalfa (Medicago sativa), and carrot (Daucus carota). The range of phytotoxicity of the antibiotics was large, with EC₂₅s ranging from 3.9 μg/L to >10,000 μg/L. Chlortetracycline, levofloxacin, and sulfamethoxazole were the most phytotoxic antibiotics. D. carota was the most sensitive plant species, often by an order of magnitude or more, followed by L. sativa and then M. sativa. Plant germination was insensitive to the antibiotics, with no significant decreases up to the highest treatment concentration of 10,000 μg/L. Compared with shoot and total length measurements, root elongation was consistently the most sensitive end point. Overall, there were few instances where measured soil concentrations, if available in the publicly accessible literature, would be expected to exceed the effect concentrations of the antibiotics evaluated in this study. The use of screening assays as part of a tiered approach for evaluating environmental impacts of antibiotics can provide insight into relative species sensitivity and serve as a basis by which to screen the potential for toxic effects of novel compounds to plants.

Field drains as a route of rapid nutrient export from agricultural land receiving biosolids.

PubMed

Heathwaite, A L; Burke, S P; Bolton, L

2006-07-15

We report research on the environmental risk of incidental nutrient transfers from land to water for biosolids amended soils. We show that subsurface (drainflow) pathways of P transport may result in significant concentrations, up to 10 mg total P l(-1), in the drainage network of an arable catchment when a P source (recent biosolids application) coincides with a significant and active transport pathway (rainfall event). However, the high P concentrations were short-lived, with drainage ditch total P concentrations returning to pre-storm concentrations within a few days of the storm event. In the case of the drainflow concentrations reported here, the results are unusual in that they describe an 'incidental event' for a groundwater catchment where such events might normally be expected to be rare owing to the capacity of the hydrological system to attenuate nutrient fluxes for highly adsorbed elements such as P. Consequently, there is a potential risk of P transfers to shallow groundwater systems. We suggest that the findings are not specific to biosolids-alone, which is a highly regulated industry, but that similar results may be anticipated had livestock waste or mineral fertilizer been applied, although the magnitude of losses may differ. The risk appears to be more one of timing and the availability of a rapid transport pathway than of P source.

Greater antioxidant and respiratory metabolism in field-grown soybean exposed to elevated O3 under both ambient and elevated CO2.

PubMed

Gillespie, Kelly M; Xu, Fangxiu; Richter, Katherine T; McGrath, Justin M; Markelz, R J Cody; Ort, Donald R; Leakey, Andrew D B; Ainsworth, Elizabeth A

2012-01-01

Antioxidant metabolism is responsive to environmental conditions, and is proposed to be a key component of ozone (O(3)) tolerance in plants. Tropospheric O(3) concentration ([O(3)]) has doubled since the Industrial Revolution and will increase further if precursor emissions rise as expected over this century. Additionally, atmospheric CO(2) concentration ([CO(2)]) is increasing at an unprecedented rate and will surpass 550 ppm by 2050. This study investigated the molecular, biochemical and physiological changes in soybean exposed to elevated [O(3) ] in a background of ambient [CO(2)] and elevated [CO(2)] in the field. Previously, it has been difficult to demonstrate any link between antioxidant defences and O(3) stress under field conditions. However, this study used principle components analysis to separate variability in [O(3)] from variability in other environmental conditions (temperature, light and relative humidity). Subsequent analysis of covariance determined that soybean antioxidant metabolism increased with increasing [O(3)], in both ambient and elevated [CO(2)]. The transcriptional response was dampened at elevated [CO(2)], consistent with lower stomatal conductance and lower O(3) flux into leaves. Energetically expensive increases in antioxidant metabolism and tetrapyrrole synthesis at elevated [O(3)] were associated with greater transcript levels of enzymes involved in respiratory metabolism. © 2011 Blackwell Publishing Ltd.

Technical and Non-Technical Measures for air pollution emission reduction: The integrated assessment of the regional Air Quality Management Plans through the Italian national model

NASA Astrophysics Data System (ADS)

D'Elia, I.; Bencardino, M.; Ciancarella, L.; Contaldi, M.; Vialetto, G.

2009-12-01

The Italian Air Quality legislation underwent sweeping changes with the implementation of the 1996 European Air Quality Framework Directive when the Italian administrative Regions were entrusted with air quality management tasks. The most recent Regional Air Quality Management Plans (AQMPs) highlighted the importance of Non-Technical Measures (NTMs), in addition to Technical Measures (TMs), in meeting environmental targets. The aim of the present work is to compile a list of all the TMs and NTMs taken into account in the Italian Regional AQMPs and to give in the target year, 2010, an estimation of SO 2, NO x and PM 10 emission reductions, of PM 10 concentration and of the health impact of PM 2.5 concentrations in terms of Life Expectancy Reduction. In order to do that, RAINS-Italy, as part of the National Integrated Modeling system for International Negotiation on atmospheric pollution (MINNI), has been applied. The management of TMs and NTMs inside RAINS have often obliged both the introduction of exogenous driving force scenarios and the control strategy modification. This has inspired a revision of the many NTM definitions and a clear choice of the definition adopted. It was finally highlighted that only few TMs and NTMs implemented in the AQMPs represent effective measures in reaching the environmental targets.

Health Benefits of Decreases in PM2.5 and Ozone in the United States from 1998 to 2016

NASA Astrophysics Data System (ADS)

Nawaz, O.; Zhang, Y.; Tong, D.; van Donkelaar, A.; Martin, R.; West, J. J.

2017-12-01

Between 1990 and 2015 the US average concentration of PM2.5 decreased by 37% and ozone decreased by 22%, driven by environmental regulations and technological advances. These decreases in pollutants are expected to have brought substantial benefits for public health in the US. Here we assess the effects of this decrease by estimating the total burden of PM2.5 and ozone on premature mortality, each year between 1998-2016. Two data sets of ambient concentration were implemented in the health impact analysis that included different subsets of the time period. First, we use data from the North American Chemical Reanalysis project, which uses OMI NO2 and MODIS AOD observations for data assimilation to constrain ozone and PM2.5 between 2009-2016. Second, we use satellite-derived estimates of ground-level PM2.5 using AOD retrievals from NASA satellites combined with the GEOS-Chem chemical transport model between 1998-2015; these estimates are calibrated to ground-based observations using a geographically weighted regression. Using yearly data on population and baseline mortality provided by the Centers for Disease Control (CDC), we assess how air pollution-related mortality has changed annually within the continental United States, and analyze trends to determine how effectively the health burden has been reduced by environmental regulations and other factors.

NDE of the space shuttle orbiter thermal protection system: Phase 2 final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tow, D.M.; Barna, B.A.; Rodriguez, J.G.

1989-03-01

Research continued on the development of a nondestructive evaluation technique for inspecting bonds on the space shuttle orbiter thermal protection system tiles. The approach taken uses a noncontacting laser sensor to measure the vibrational response of bonded tiles to acoustical excitation. Laboratory work concentrated on investigating the dynamic response of ''acreage'' tiles, i.e., tiles covering the underside of the orbiter, all approximately square. A number of promising unbond signatures have been identified in the time and frequency domain response. Field tests were conducted to study environmental effects on the techniques being developed. The ambient motion of the orbiter was foundmore » to be larger than expected, necessitating modifications to current techniques. 2 refs., 21 figs., 1 tab.« less

Assessing the potential environmental impact of Athabasca oil sands development in lakes across Northwest Saskatchewan

NASA Astrophysics Data System (ADS)

Ahad, J. M.; Cumming, B. F.; Das, B.; Sanei, H.

2011-12-01

The continued development of Canada's Athabasca oil sands poses a significant environmental challenge. Low buffered boreal lakes located downwind of the prevailing eastward wind direction may be threatened by acidification and elevated inputs of airborne contaminants such as polycyclic aromatic hydrocarbons (PAHs). An accurate assessment of the impact that increased levels of bitumen production may have on lakes in the region requires an understanding of the historic variability within these systems prior to at least the past several decades. Here we report concentrations of PAHs, δ13C and δ15N of organic matter (OM), Rock-Eval pyrolysis analyses, and distributions of n-alkanes in dated sediment cores from ten lakes located across NW Saskatchewan. Concentrations of PAHs were relatively low (< 100 ng/g for Σ 16 EPA Priority PAHs at each lake) and in general showed no substantial increases over the past 30 years. Retene, which is often associated with the combustion of coniferous wood, was generally the most abundant PAH amongst those reported, demonstrating the importance of forest fires as a principal PAH source. Plots of Hydrogen Index (HI) versus Oxygen Index (OI) fell within a relatively narrow range typical for sediments containing a high content of algal-derived OM. Relatively lower C/N ratios and higher abundances of C17 n-alkane in more recent sediments pointed to an increasingly larger component of algal-derived OM. In all ten lakes δ13C showed gradual upcore depletions that fell within the expected range for fossil fuel combustion (i.e., Suess effect), although this alone may not explain the up to ~3% depletion observed in several of the lakes. In conjunction with the other upcore trends these data may suggest a possible increase in primary productivity over the past several decades in many of the lakes studied. δ15N signatures were more variable, showing upcore increases in some lakes and upcore depletions in others. The increasingly lighter values observed in more recent sediments in some lakes suggest a potential input of depleted bioavailable nitrogen, as might be expected from anthropogenic NOx emissions. This study implies that thus far it appears that oil sands industry related emissions have had only a minor environmental impact on lakes in NW Saskatchewan.

The combined impact of land use change and aquaculture on sediment and water quality in oligotrophic Lake Rupanco (North Patagonia, Chile, 40.8°S).

PubMed

León-Muñoz, Jorge; Echeverría, Cristian; Marcé, Rafael; Riss, Wolfgang; Sherman, Bradford; Iriarte, Jose Luis

2013-10-15

Water and sediment quality in North Patagonia's large, oligotrophic lakes are expected to suffer as native forest continues to be fragmented and degraded by its conversion to cropping and pasture land uses. These changes in land use are expected to increase diffuse nutrient loads to the region's lakes. In addition, these lakes are home to the world's second largest salmon aquaculture industry which provides additional point sources of nutrients within the lakes. We studied the combined influences of land use change and salmon farming on the nutrient concentrations in a North Patagonian lake (Lake Rupanco, 233 km(2) water surface, 163 m average depth) in four sub-watersheds ranging in disturbance from near-pristine forest to 53% converted to cropping and pasture. Nitrogen exports from the tributary sub-watersheds increased from 33 kg TN/km(2)/y to 621 kg TN/km(2)/y as the proportion of crop and pasture land increased. The combined nutrient load from land use change and salmon farming has led to significant differences in the nitrogen concentrations of the lake's water column and sediments in the near-shore zones across the lake. Total nitrogen concentrations in the sediments varied from 37 ± 18 mg/kg in near-pristine sub-watersheds without salmon farming to 6400 ± 698 mg/kg where the sub-watershed was dominated by crop and pasture lands combined with the presence of salmon farming. These results demonstrate the importance of considering the impacts of both salmon farming and land use on water and sediment quality for future environmental planning, management and decision making. Copyright © 2013 Elsevier Ltd. All rights reserved.

Method for determination of methyl tert-butyl ether and its degradation products in water

USGS Publications Warehouse

Church, C.D.; Isabelle, L.M.; Pankow, J.F.; Rose, D.L.; Tratnyek, P.G.

1997-01-01

An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method can also give simultaneous identification of polar compounds that might occur as degradation products of gasoline oxygenates, such as TBA, TBF, TAA, methyl acetate, and acetone. When the method was applied to effluent from a column microcosm prepared with core material from an urban site in New Jersey, conversion of MTBE to TBA was observed after a lag period of 35 days. However, to date, analyses of water samples from six field sites using the DAI-GC/MS method have not produced evidence for the expected products of in situ degradation of MTBE.An analytical method is described that can detect the major alkyl ether compounds that are used as gasoline oxygenates (methyl tert-butyl ether, MTBE; ethyl tert-butyl ether, ETBE; and tert-amyl methyl ether, TAME) and their most characteristic degradation products (tert-butyl alcohol, TBA; tert-butyl formate, TBF; and tert-amyl alcohol, TAA) in water at sub-ppb concentrations. The new method involves gas chromatography (GC) with direct aqueous injection (DAI) onto a polar column via a splitless injector, coupled with detection by mass spectrometry (MS). DAI-GC/MS gives excellent agreement with conventional purge-and-trap methods for MTBE over a wide range of environmentally relevant concentrations. The new method can also give simultaneous identification of polar compounds that might occur as degradation products of gasoline oxygenates, such as TBA, TBF, TAA, methyl acetate, and acetone. When the method was applied to effluent from a column microcosm prepared with core material from an urban site in New Jersey, conversion of MTBE to TBA was observed after a lag period of 35 days. However, to date, analyses of water samples from six field sites using the DAI-GC/MS method have not produced evidence for the expected products of in situ degradation of MTBE.

Observations of atmospheric methane concentrations and sources at two supersites Tiksi, northern Siberia and Pallas-Sodankylä, northern Finland (Invited)

NASA Astrophysics Data System (ADS)

Laurila, T. J.; Aurela, M.; Hatakka, J.; Aalto, T.; Lohila, A.; Asmi, E.; Kondratyev, V.; Ivakhov, V.; Reshetnikov, A.; Makshtas, A. P.; Dlugokencky, E. J.; Uttal, T.

2013-12-01

Arctic and Boreal regions are important in the global methane budget mainly because emissions are large from the extensive wetlands. Recently the potential for increased emissions from methane hydrates under sediments at the bottom of the Arctic Ocean has been recognized. Resource exploitation in the Arctic is expanding and includes gas and oil drilling. Together with climate warming, we may expect changes in methane emissions from high northern latitudes. The main tools to probe the effect of this development on atmospheric methane are atmospheric methane observations and local emission measurements by micrometeorological and chamber methods. To better understand emissions at small and large scales, so called supersites have been introduced. At these sites, both atmospheric concentrations and emissions from representative ecosystems, together with suite of other environmental information, are measured continuously. We are running two of these supersites: Pallas-Sodankylä in northern Finland and Tiksi in Siberia on the coast of the Laptev Sea. In spite of the fact that both sites are north of the Arctic Circle, environmental conditions differ very much. In northern Scandinavia, climate is relatively marine, and wetland methane emissions are active throughout the year. In continental Tiksi the active layer is 30-80 cm and methane emissions cease during the coldest months when soil temperature is close to -20°C. Air mass advection is either from continental Siberia or from the Siberian seas. Forest and tundra fires are relatively common. At Pallas, advection is from the forested boreal and industrialized areas of Europe or the Norwegian or Barents Sea. In this presentation, we show seasonal variations of atmospheric methane concentrations at World Meteorological Organization - Global Atmosphere Watch sites: Pallas-Sodankylä and Tiksi. Source areas have been analyzed by trajectories. The main sources of methane in Tiksi were wetlands and the Laptev Sea, which is oversaturated regarding methane. Concentrations and their variability were high in June-October due to terrestrial and marine emissions. Sea ice restricts marine emissions very much. Interesting periods were when the sea froze in October and when the ice melted in early July. Seasonal pattern of tundra methane emissions will be presented including growing season onset in June-July, high season in August and late season emission rates extending to winter. These will be compared to emission rates at typical northern boreal fens of the Pallas-Sodankylä site. It is expected that the Tiksi and Pallas-Sodakyla site will form the foundation for further pan-Arctic comparisons between the observatories in the IASOA consortium (www.iasoa.org).

Exploring Fifth-Grade Turkish Children's Solutions and Future Plans for Environmental Pollution through Their Drawings

ERIC Educational Resources Information Center

Saglam, Murat

2016-01-01

The pollution of land, water, air, noise, light etc. threatens people, plants, animals and ecosystems. Environmental literacy is at the heart of environmental education, and environmentally literate people are expected to be aware of how to help solve environmental problems such as pollution. The purpose of the present study is to explore 5th…

Lifetime and dissolution kinetics of zinc oxide nanoparticles in aqueous media

NASA Astrophysics Data System (ADS)

Wang, Ning; Tong, Tiezheng; Xie, Minwei; Gaillard, Jean-François

2016-08-01

We have assessed the persistence and lifetime of ZnO nanoparticles (ZnO-NPs) by performing dissolution experiments in three different aqueous media. These experiments were performed at ZnO-NP concentration levels close to the solubility of zincite (˜8 μM or 650 μg l-1 of ZnO)—a concentration that is orders of magnitude higher than current estimated relevant environmental concentrations. The kinetics were followed by voltammetry, while maintaining the pH at about 7.5 using a CO2/N2 gas mixture to remove di-oxygen interference. Our results show that, under these conditions, ZnO-NPs readily dissolve with a lifetime expectancy that does not exceed 90 min. Water chemistry, especially the presence of dissolved organic matter (DOM), plays an important role in ZnO-NP dissolution. Dissolution rates significantly increase in the presence of strong chelating agents, EDTA and L-cysteine, while the addition of polymeric DOM, such as sodium alginate, has the opposite effect. Our results suggest that ZnO-NPs are unlikely to persist in natural aqueous media and that the toxicity should be primarily related to the released Zn2+ ions rather than effects commonly associated to the presence of nanoparticles.

77 FR 62528 - Termination of Environmental Impact Statement for the General Management Plan, Mount Rushmore...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-15

... environmental impact statement (EIS) for the Mount Rushmore National Memorial General Management Plan (GMP) and will be preparing an Environmental Assessment (EA) instead. DATES: The draft GMP EA is expected to be... the appropriate level of environmental documentation for the GMP. Preliminary analysis of alternatives...

An Eco-tank system containing microbes and different aquatic plant species for the bioremediation of N,N-dimethylformamide polluted river waters.

PubMed

Xiao, Jibo; Chu, Shuyi; Tian, Guangming; Thring, Ronald W; Cui, Lingzhou

2016-12-15

An Eco-tank system of 10m was designed to simulate the natural river. It consisted of five tanks sequentially connected containing microbes, biofilm carriers and four species of floating aquatic plants. The purification performance of the system for N,N-dimethylformamide (DMF) polluted river water was evaluated by operating in continuous mode. DMF was completely removed in Tanks 1 and 2 at influent DMF concentrations between 75.42 and 161.05mg L -1 . The NH 4 + -N concentration increased in Tank 1, followed by a gradual decrease in Tanks 2-5. Removal of NH 4 + -N was enhanced by aeration. The average effluent NH 4 + -N concentration of Tank 5 decreased to a minimum of 0.89mg L -1 , corresponding to a decrease of 84.8% when compared with that before aeration. TN concentration did not decrease significantly as expected after inoculation with denitrifying bacteria. The average effluent TN concentration of the system was determined to be 4.58mg L -1 , still unable to satisfy the Class V standard for surface water environmental quality. The results of this study demonstrated that the Eco-tank system is an efficient process in removing DMF, TOC, and NH 4 + -N from DMF polluted river water. However, if possible, alternative technologies should be adopted for controlling the effluent TN concentration. Copyright © 2016 Elsevier B.V. All rights reserved.

Sex, age, and tissue specific accumulation of eight metals, arsenic, and selenium in the European hedgehog (Erinaceus europaeus).

PubMed

Rautio, Anni; Kunnasranta, Mervi; Valtonen, Anu; Ikonen, Mirva; Hyvärinen, Heikki; Holopainen, Ismo J; Kukkonen, Jussi V K

2010-11-01

Many insectivores have been shown to be sensitive to heavy metals and therefore suitable for biomonitoring purposes. In Finland, the hibernation period of the European hedgehog (Erinaceus europaeus) is long, and during hibernation the stress caused by environmental toxins may be crucial. Concentrations of cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), arsenic (As), and selenium (Se) were measured in a population of hedgehogs in the town of Joensuu in eastern Finland during the summers of 2004 and 2005. The analyzed tissues were kidney, liver, hair, and spine. The sampled hedgehogs (n = 65) were mainly road-killed animals. As expected, the concentrations of heavy metals were low because the hedgehogs were living in a comparatively unpolluted area. Significant increases with age were found in Cd concentrations (kidney, liver, and spine) and some essential elements (Se in spine, kidney, and liver; Mo in kidney and liver; Cu in spine; Fe in liver; and Mn in spine). Age accumulation and correlations between Se and Cd and between Mo and Cd may indicate the protective roles of Se and Mo against Cd toxicity in hedgehogs, in which Cd is already at comparatively low concentrations. Sex had no significant effect on concentrations of the elements studied. In conclusion, age is an important parameter to be taken into account when studying heavy-metal concentrations in hedgehogs and other insectivores.

Using subjective expectations to forecast longevity: do survey respondents know something we don't know?

PubMed

Perozek, Maria

2008-02-01

Old-age mortality is notoriously difficult to predict because it requires not only an understanding of the process of senescence-which is influenced by genetic, environmental, and behavioral factors-but also a prediction of how these factors will evolve. In this paper I argue that individuals are uniquely qualified to predict their own mortality based on their own genetic background, as well as environmental and behavioral risk factors that are often known only to the individual. Given this private information, individuals form expectations about survival probabilities that may provide additional information to demographers and policymakers in their challenge to predict mortality. From expectations data from the 1992 Health and Retirement Study (HRS), I construct subjective, cohort life tables that are shown to predict the unusual direction of revisions to U.S. life expectancy by gender between 1992 and 2004: that is, for these cohorts, the Social Security Actuary (SSA) raised male life expectancy in 2004 and at the same lowered female life expectancy, narrowing the gender gap in longevity by 25% over this period. Further, although the subjective life expectancies for men appear to be roughly in line with the 2004 life tables, the subjective expectations of women suggest that female life expectancies estimated by the SSA might still be on the high side.

Impact of an asbestos cement factory on mesothelioma incidence: global assessment of effects of occupational, familial, and environmental exposure.

PubMed

Mensi, Carolina; Riboldi, Luciano; De Matteis, Sara; Bertazzi, Pier Alberto; Consonni, Dario

2015-01-01

Few studies have examined the incidence of malignant mesothelioma (MM) associated with distinct sources of asbestos exposure (occupational, familial, or environmental). We assessed the impact of asbestos exposure-global and by source-on the incidence of MM in Broni, an Italian town in which an asbestos cement factory once operated (1932-1993). Based on data collected by the Lombardy Mesothelioma Registry, we calculated the number of observed and expected MM cases among workers, their cohabitants, and people living in the area in 2000-2011. We identified 147 MM cases (17.45 expected), 138 pleural and nine peritoneal, attributable to exposure to asbestos from the factory. Thirty-eight cases had past occupational exposure at the factory (2.33 expected), numbering 32 men (26 pleural, six peritoneal) and six women (four pleural, two peritoneal). In the families of the workers, there were 37 MM cases (4.23 expected), numbering five men (all pleural) and 32 women (31 pleural, one peritoneal). Among residents in Broni or in the adjacent/surrounding towns, there were 72 cases of pleural MM (10.89 expected), numbering 23 men and 49 women. The largest MM excess was found in the towns of Broni (48 observed, 3.68 expected) and Stradella (16 observed, 1.85 expected). This study documents the large impact of the asbestos cement factory, with about 130 excess MM cases in a 12-year period. The largest MM burden was among women, from non-occupational exposure. Almost half of the MM cases were attributable to environmental exposure. Copyright © 2014 Elsevier Ltd. All rights reserved.

Monitoring marine heavy metal contamination via the chemical analysis of foraminifera and growth increments in bivalves - a pilot study from a Pb and Zn mining region in western Greenland

NASA Astrophysics Data System (ADS)

Jessen, C.; Asmund, G.; Elberling, B.; Frei, D.; Knudsen, C.; Rasmussen, P.

2011-12-01

Annual monitoring of heavy metal concentrations in the fjords (sea water, seaweed, lichens, blue mussels, shorthorn sculpin and Northern prawn) adjacent to the Black Angel lead-zinc mine (active 1973-1990) at Maarmorilik, western Greenland was initiated during operation of the mine and continues through to today. This pilot study tests whether the calcareous shells of bivalves and foraminifera register these known variations in heavy metal concentrations. Live individuals of Mytilus edulis were collected through a transect of monitoring stations in 2009 and PB-Zn concentrations were measured at multiple points within the yearly increments using LA-ICP-MS. Individuals aged between 12 and 28 years were measured and demonstrated a clear signal of mine closure even at 40 km distance from the plant. Foraminifera (Melonis barleeanus) from a sediment core dating from 1880 AD to present have previously been shown to display a greater percentage of deformities during the period of mining activity (Elberling et al. 2003) possibly suggesting a correlation between heavy metal concentrations in sea water and morphological development. LA-ICP-MS analysis of individual foraminifera confirms an increase in Pb-Zn uptake during mining operations. Although it could therefore be expected that Pb-Zn concentrations would be enhanced in the 'deformed' foraminifera relative to the 'non-deformed', no difference in Pb-Zn was concentrations was detected. This short pilot study (Jessen et al.2010) demonstrates the potential of calcareous material as indicators of environmental pollution and their applicability as a monitoring tool in remote regions. Jessen CA, Asmund G, Elberling B, Frei D, Knudsen C and Rasmussen P. 2010 Monitoring marine heavy metal contamination via the chemical analysis of growth increments in bivalves - a pilot study. Danmarks og Grønlands Geologiske Undersøgelse Rapport 2010/86. 1-20 Elberling, B., Knudsen, K. L., Kristensen, P. H., and Asmund, G. (2003) Applying foraminiferal stratigraphy as a biomarker for heavy metal contamination and mining impact in a fiord in West Greenland. Marine Environmental Research 55, 235-256

Environmental fate and effects of nicotine released during cigarette production.

PubMed

Seckar, Joel A; Stavanja, Mari S; Harp, Paul R; Yi, Yongsheng; Garner, Charles D; Doi, Jon

2008-07-01

A variety of test methods were used to study the gradation, bioaccumulation, and toxicity of nicotine. Studies included determination of the octanol-water partition coefficient, conversion to CO2 in soil and activated sludge, and evaluation of the effects on microbiological and algal inhibition as well as plant germination and root elongation. The partitioning of nicotine between octanol and water indicated that nicotine will not bioaccumulate regardless of the pH of the medium. The aqueous and soil-based biodegradation studies indicated that nicotine is readily biodegradable in both types of media. The microbiological inhibition and aquatic and terrestrial toxicity tests indicated that nicotine has low toxicity. The U.S. Environmental Protection Agency Persistence, Bioaccumulation, and Toxicity Profiler model, based on the structure of nicotine and the predictive rates of hydroxyl radical and ozone reactions, estimated an atmospheric half-life of less than 5.0 h. Using this value in the Canadian Environmental Modeling Center level III model, the half-life of nicotine was estimated as 3.0 d in water and 0.5 d in soil. This model also estimated nicotine discharge into the environment; nicotine would be expected to be found predominantly in water (93%), followed by soil (4%), air (3%), and sediment (0.4%). Using the estimated nicotine concentrations in water, soil, and sediment and the proper median effective concentrations derived from the algal growth, biomass inhibition, and buttercrunch lettuce (Lactuca sativa) seed germination and root elongation studies, hazard quotients of between 10(-7) and 10(-8) were calculated, providing further support for the conclusion that the potential for nicotine toxicity to aquatic and terrestrial species in the environment is extremely low.

Synergistic interactions of biotic and abiotic environmental stressors on gene expression.

PubMed

Altshuler, Ianina; McLeod, Anne M; Colbourne, John K; Yan, Norman D; Cristescu, Melania E

2015-03-01

Understanding the response of organisms to multiple stressors is critical for predicting if populations can adapt to rapid environmental change. Natural and anthropogenic stressors often interact, complicating general predictions. In this study, we examined the interactive and cumulative effects of two common environmental stressors, lowered calcium concentration, an anthropogenic stressor, and predator presence, a natural stressor, on the water flea Daphnia pulex. We analyzed expression changes of five genes involved in calcium homeostasis - cuticle proteins (Cutie, Icp2), calbindin (Calb), and calcium pump and channel (Serca and Ip3R) - using real-time quantitative PCR (RT-qPCR) in a full factorial experiment. We observed strong synergistic interactions between low calcium concentration and predator presence. While the Ip3R gene was not affected by the stressors, the other four genes were affected in their transcriptional levels by the combination of the stressors. Transcriptional patterns of genes that code for cuticle proteins (Cutie and Icp2) and a sarcoplasmic calcium pump (Serca) only responded to the combination of stressors, changing their relative expression levels in a synergistic response, while a calcium-binding protein (Calb) responded to low calcium stress and the combination of both stressors. The expression pattern of these genes (Cutie, Icp2, and Serca) were nonlinear, yet they were dose dependent across the calcium gradient. Multiple stressors can have complex, often unexpected effects on ecosystems. This study demonstrates that the dominant interaction for the set of tested genes appears to be synergism. We argue that gene expression patterns can be used to understand and predict the type of interaction expected when organisms are exposed simultaneously to natural and anthropogenic stressors.

Neurotoxic effects of perfluoroalkylated compounds: mechanisms of action and environmental relevance.

PubMed

Mariussen, Espen

2012-09-01

Perfluoroalkylated compounds (PFCs) are used in fire-fighting foams, treatment of clothes, carpets and leather products, and as lubricants, pesticides, in paints and medicine. Recent developments in chemical analysis have revealed that fluorinated compounds have become ubiquitously spread and are regarded as a potential threats to the environment. Due to the carbon-fluorine bond, which has a very high bond strength, these chemicals are extremely persistent towards degradation and some PFCs have a potential for bioaccumulation in organisms. Of particular concern has been the developmental toxicity of PFOS and PFOA, which has been manifested in rodent studies as high mortality of prenatally exposed newborn rats and mice within 24 h after delivery. The nervous system appears to be one of the most sensitive targets of environmental contaminants. The serious developmental effects of PFCs have lead to the upcoming of studies that have investigated neurotoxic effects of these substances. In this review the major findings of the neurotoxicity of the main PFCs and their suggested mechanisms of action are presented. The neurotoxic effects are discussed in light of other toxic effects of PFCs to indicate the significance of PFCs as neurotoxicants. The main findings are that PFCs may induce neurobehavioral effects, particularly in developmentally exposed animals. The effects are, however, subtle and inconclusive and are often induced at concentrations where other toxic effects also are expected. Mechanistic studies have shown that PFCs may affect the thyroid system, influence the calcium homeostasis, protein kinase C, synaptic plasticity and cellular differentiation. Compared to other environmental toxicants the human blood levels of PFCs are high and of particular concern is that susceptible groups may be exposed to a cocktail of substances that in combination reach harmful concentrations.

40 CFR 35.137 - Application requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... expected environmental or other benefits to be achieved, and the anticipated impact on any environmental programs or program areas proposed for reduced effort. (b) The applicant and the Regional Administrator...

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: ECR TECHNOLOGIES, INC., EARTHLINKED GROUND-SOURCE HEAT PUMP WATER HEATING SYSTEM

EPA Science Inventory

EPA has created the Environmental Technology Verification program to provide high quality, peer reviewed data on technology performance. This data is expected to accelerate the acceptance and use of improved environmental protection technologies. The Greenhouse Gas Technology C...

The Interactive Effect of Pro-Environmental Disciplinary Concentration under Cooperation versus Competition Contexts

ERIC Educational Resources Information Center

Cuadrado, Esther; Tabernero, Carmen; García, Rocío; Luque, Bárbara

2017-01-01

This research explores the relevance of cooperation and students' environmental disciplinary concentration on decision-making with respect to environmental issues--specifically the use of water, a limited common-pool resource. For this purpose, 61 environmental sciences students and 46 educational sciences students played the role of farmers and…

An Analysis of Terrestrial and Aquatic Environmental Controls of Riverine Dissolved Organic Carbon in the Conterminous United States

DOE PAGES

Yang, Qichun; Zhang, Xuesong; Xu, Xingya; ...

2017-05-29

Riverine carbon cycling is an important, but insufficiently investigated component of the global carbon cycle. Analyses of environmental controls on riverine carbon cycling are critical for improved understanding of mechanisms regulating carbon processing and storage along the terrestrial-aquatic continuum. Here, we compile and analyze riverine dissolved organic carbon (DOC) concentration data from 1402 United States Geological Survey (USGS) gauge stations to examine the spatial variability and environmental controls of DOC concentrations in the United States (U.S.) surface waters. DOC concentrations exhibit high spatial variability, with an average of 6.42 ± 6.47 mg C/ L (Mean ± Standard Deviation). In general,more » high DOC concentrations occur in the Upper Mississippi River basin and the Southeastern U.S., while low concentrations are mainly distributed in the Western U.S. Single-factor analysis indicates that slope of drainage areas, wetlands, forests, percentage of first-order streams, and instream nutrients (such as nitrogen and phosphorus) pronouncedly influence DOC concentrations, but the explanatory power of each bivariate model is lower than 35%. Analyses based on the general multi-linear regression models suggest DOC concentrations are jointly impacted by multiple factors. Soil properties mainly show positive correlations with DOC concentrations; forest and shrub lands have positive correlations with DOC concentrations, but urban area and croplands demonstrate negative impacts; total instream phosphorus and dam density correlate positively with DOC concentrations. Notably, the relative importance of these environmental controls varies substantially across major U.S. water resource regions. In addition, DOC concentrations and environmental controls also show significant variability from small streams to large rivers, which may be caused by changing carbon sources and removal rates by river orders. In sum, our results reveal that general multi-linear regression analysis of twenty one terrestrial and aquatic environmental factors can partially explain (56%) the DOC concentration variation. In conclusion, this study highlights the complexity of the interactions among these environmental factors in determining DOC concentrations, thus calls for processes-based, non-linear methodologies to constrain uncertainties in riverine DOC cycling.« less

Theoretical Explanations of Environmental Motivations and Expectations of Clients on Green Building Demand and Investment

NASA Astrophysics Data System (ADS)

Iheanyichukwu Joachim, Onuoha; Kamarudin, Norhaya; Uche Aliagha, Godwin; Ufere, Kalu Joseph

2015-01-01

In building industry, green demand and investment creates a positive footprint on the environment. However, these environmental opportunities have not been adequately harnessed and explored by Clients of green building apparently because of poor understanding of the motivating drivers and benefits accruing from green building demand and investment. The decision to demand for or invest in green building is influenced by certain environmental motivating drivers and expectations which have not been fully examined by researchers and not well understood by stakeholders. Based on the Theory of Planned Behaviour (TPB) and Theory of Value Belief Norm (VBN) explanations, this study focused on the Clients, purchasers and users' motivations and intentions to go for green building. Based on the reviewed theories, we hypothesized that environmental motivations and expectations for green building demand and investment are embedded in the environmental quest for protection of eco-system and bio-diversity, improvement of water and air quality, reduction of solid waste, conservation of natural resources, reduction of societal costs of landfill creation and maintenance, minimization of site impact and reduction emission to air and enhanced energy efficiency. However, the predictive validity of these propositions depends on the client's beliefs, values, social pressure, and perceived behavioural control.

Contents and leachability of heavy metals (Pb, Cu, Sb, Zn, As) in soil at the Pantex firing range, Amarillo, Texas.

PubMed

Basunia, S; Landsberger, S

2001-10-01

Pantex firing range soil samples were analyzed for Pb, Cu, Sb, Zn, and As. One hundred ninety-seven samples were collected from the firing range and vicinity area. There was a lack of knowledge about the distribution of Pb in the firing range, so a random sampling with proportional allocation was chosen. Concentration levels of Pb and Cu in the firing range were found to be in the range of 11-4675 and 13-359 mg/kg, respectively. Concentration levels of Sb were found to be in the range of 1-517 mg/kg. However, the Zn and As concentration levels were close to average soil background levels. The Sn concentration level was expected to be higher in the Pantex firing range soil samples. However, it was found to be below the neutron activation analysis (NAA) detection limit of 75 mg/kg. Enrichment factor analysis showed that Pb and Sb were highly enriched in the firing range with average magnitudes of 55 and 90, respectively. Cu was enriched approximately 6 times more than the usual soil concentration levels. Toxicity characteristic leaching procedure (TCLP) was carried out on size-fractionated homogeneous soil samples. The concentration levels of Pb in leachates were found to be approximately 12 times higher than the U.S. Environmental Protection Agency (EPA) regulatory concentration level of 5 mg/L. Sequential extraction (SE) was also performed to characterize Pb and other trace elements into five different fractions. The highest Pb fraction was found with organic matter in the soil.

75 FR 1802 - Termination of the Environmental Impact Statement for the General Management Plan, Gila Cliff...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-13

... Management Plan because it has determined that an Environmental Assessment (EA) is the more appropriate... Assessment was approved by the Chief of the NPS Environmental Quality Division on November 4, 2009. The draft general management plan and Environmental Assessment is expected to be distributed for a 30 day public...

Comparative Study of Effects of CO 2 Concentration and pH on Microbial Communities from a Saline Aquifer, a Depleted Oil Reservoir, and a Freshwater Aquifer

DOE PAGES

Gulliver, Djuna M.; Lowry, Gregory V.; Gregory, Kelvin B.

2016-08-09

Injected CO 2 from geologic carbon storage is expected to impact the microbial communities of proposed storage sites, such as depleted oil reservoirs and deep saline aquifers, as well as overlying freshwater aquifers at risk of receiving leaking CO 2. Microbial community change in these subsurface sites may affect injectivity of CO 2, permanence of stored CO 2, and shallow subsurface water quality. The effect of CO 2 concentration on the microbial communities in fluid collected from a depleted oil reservoir and a freshwater aquifer was examined at subsurface pressures and temperatures. The community was exposed to 0%, 1%, 10%,more » and 100% pCO 2 for 56 days. Bacterial community structure was analyzed through 16S rRNA gene clone libraries, and total bacterial abundance was estimated through quantitative polymerase chain reaction. Changes in the microbial community observed in the depleted oil reservoir samples and freshwater samples were compared to previous results from CO 2-exposed deep saline aquifer fluids. Overall, results suggest that CO 2 exposure to microbial communities will result in pH-dependent population change, and the CO 2-selected microbial communities will vary among sites. In conclusion, this is the first study to compare the response of multiple subsurface microbial communities at conditions expected during geologic carbon storage, increasing the understanding of environmental drivers for microbial community changes in CO 2-exposed environments.« less

Comparative Study of Effects of CO 2 Concentration and pH on Microbial Communities from a Saline Aquifer, a Depleted Oil Reservoir, and a Freshwater Aquifer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gulliver, Djuna M.; Lowry, Gregory V.; Gregory, Kelvin B.

Injected CO 2 from geologic carbon storage is expected to impact the microbial communities of proposed storage sites, such as depleted oil reservoirs and deep saline aquifers, as well as overlying freshwater aquifers at risk of receiving leaking CO 2. Microbial community change in these subsurface sites may affect injectivity of CO 2, permanence of stored CO 2, and shallow subsurface water quality. The effect of CO 2 concentration on the microbial communities in fluid collected from a depleted oil reservoir and a freshwater aquifer was examined at subsurface pressures and temperatures. The community was exposed to 0%, 1%, 10%,more » and 100% pCO 2 for 56 days. Bacterial community structure was analyzed through 16S rRNA gene clone libraries, and total bacterial abundance was estimated through quantitative polymerase chain reaction. Changes in the microbial community observed in the depleted oil reservoir samples and freshwater samples were compared to previous results from CO 2-exposed deep saline aquifer fluids. Overall, results suggest that CO 2 exposure to microbial communities will result in pH-dependent population change, and the CO 2-selected microbial communities will vary among sites. In conclusion, this is the first study to compare the response of multiple subsurface microbial communities at conditions expected during geologic carbon storage, increasing the understanding of environmental drivers for microbial community changes in CO 2-exposed environments.« less

Development of a probabilistic PCB-bioaccumulation model for six fish species in the Hudson River

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stackelberg, K. von; Menzie, C.

1995-12-31

In 1984 the US Environmental Protection Agency (USEPA) completed a Feasibility Study on the Hudson River that investigated remedial alternatives and issued a Record of Decision (ROD) later that year. In December 1989 USEPA decided to reassess the No Action decision for Hudson River sediments. This reassessment consists of three phases: Interim Characterization and Evaluation (Phase 1); Further Site Characterization and Analysis (Phase 2); and, Feasibility study (Phase 3). A Phase 1 report was completed in August, 1991. The team then completed a Final Work Plan for Phase 2 in September 1992. This work plan identified various PCB fate andmore » transport modeling activities to support the Hudson River PCB Reassessment Remedial Investigation and Feasibility Study (RI/FS). This talk provides a description of the development of a Probabilistic bioaccumulation models to describe the uptake of PCBs on a congener-specific basis in six fish species. The authors have developed a framework for relating body burdens of PCBs in fish to exposure concentrations in Hudson River water and sediments. This framework is used to understand historical and current relationships as well as to predict fish body burdens for future conditions under specific remediation and no action scenarios. The framework incorporates a probabilistic approach to predict distributions in PCB body burdens for selected fish species. These models can predict single population statistics such as the average expected values of PCBs under specific scenarios as well as the distribution of expected concentrations.« less

A demonstration of mitigation of environmentally-assisted cracking by the application of a tensile overload

DOE Office of Scientific and Technical Information (OSTI.GOV)

James, L.A.

1997-02-01

Environmentally-assisted cracking (EAC) of low-alloy steels in high-temperature aqueous environments typical of those employed in light-water reactor (LWR) systems has been a subject of considerable interest since the pioneering work of Kondo et al demonstrated significantly higher fatigue crack propagation (FCP) rates in water than would be expected in an air environment under similar conditions. Here, environmentally-assisted cracking (EAC) of low-alloy steels in elevated temperature aqueous environments is readily observed in many laboratory experiments conducted in autoclaves, yet the observation of EAC in actual components operating in the same environments is quite rare. Mass transport of sulfides from the crackmore » enclave by diffusion and convection occurring in operating components provides one plausible explanation to this apparent paradox. Another contribution to EAC mitigation may also arise from the non-constant stress amplitudes typical for many operating components. This paper provides a demonstration of how a single tensile overload to 40% above a steady-state maximum fatigue stress can retard subsequent crack growth at the steady-state level for a sufficient period of time that diffusion mass transport can reduce the crack-tip sulfide concentration to a level below that necessary to sustain EAC.« less

Assessment of DDT levels in selected environmental media and biological samples from Mexico and Central America.

PubMed

Pérez-Maldonado, Iván N; Trejo, Antonio; Ruepert, Clemens; Jovel, Reyna del Carmen; Méndez, Mónica Patricia; Ferrari, Mirtha; Saballos-Sobalvarro, Emilio; Alexander, Carlos; Yáñez-Estrada, Leticia; Lopez, Dania; Henao, Samuel; Pinto, Emilio R; Díaz-Barriga, Fernando

2010-03-01

Taking into account the environmental persistence and the toxicity of DDT, the Pan American Health Organization (PAHO) organized a surveillance program in Mesoamerica which included the detection of residual DDT in environmental (soil) and biological samples (fish tissue and children's blood). This program was carried out in communities from Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama. This paper presents the first report of that program. As expected, the results show that the levels for [summation operator] DDT in soil (outdoor or indoor) and fish samples in the majority of the locations studied are below guidelines. However, in some locations, we found children with high concentrations of DDT as in Mexico (mean level 50.2 ng/mL). Furthermore, in some communities and for some matrices, the DDT/DDE quotient is higher than one and this may reflect a recent DDT exposure. Therefore, more efforts are needed to avoid exposure and to prevent the reintroduction of DDT into the region. In this regard it is important to know that under the surveillance of PAHO and with the support of UNEP, a regional program in Mesoamerica for the collection and disposal of DDT and other POPs stockpiles is in progress. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

Through the eyes of children: perceptions of environmental change in tropical forests.

PubMed

Pellier, Anne-Sophie; Wells, Jessie A; Abram, Nicola K; Gaveau, David; Meijaard, Erik

2014-01-01

This study seeks to understand children's perceptions of their present and future environments in the highly biodiverse and rapidly changing landscapes of Kalimantan, Indonesian Borneo. We analyzed drawings by children (target age 10-15 years) from 22 villages, which show how children perceive the present conditions of forests and wildlife surrounding their villages and how they expect conditions to change over the next 15 years. Analyses of picture elements and their relationships to current landscape variables indicate that children have a sophisticated understanding of their environment and how different environmental factors interact, either positively or negatively. Children appear to have landscape-dependent environmental perceptions, showing awareness of past environmental conditions and many aspects of recent trends, and translating these into predictions for future environmental conditions. The further removed their present landscape is from the originally forested one, the more environmental change they expect in the future, particularly declines in forest cover, rivers, animal diversity and increases in temperature and natural disasters. This suggests that loss of past perceptions and associated "shifting environmental baselines" do not feature strongly among children on Borneo, at least not for the perceptions we investigated here. Our findings that children have negative expectations of their future environmental conditions have important political implications. More than other generations, children have a stake in ensuring that future environmental conditions support their long-term well-being. Understanding what drives environmental views among children, and how they consider trade-offs between economic development and social and environmental change, should inform optimal policies on land use. Our study illuminates part of the complex interplay between perceptions of land cover and land use change. Capturing the views of children through artistic expressions provides a potentially powerful tool to influence public and political opinions, as well as a valuable approach for developing localized education and nature conservation programs.

Through the Eyes of Children: Perceptions of Environmental Change in Tropical Forests

PubMed Central

Pellier, Anne-Sophie; Wells, Jessie A.; Abram, Nicola K.; Gaveau, David; Meijaard, Erik

2014-01-01

This study seeks to understand children's perceptions of their present and future environments in the highly biodiverse and rapidly changing landscapes of Kalimantan, Indonesian Borneo. We analyzed drawings by children (target age 10–15 years) from 22 villages, which show how children perceive the present conditions of forests and wildlife surrounding their villages and how they expect conditions to change over the next 15 years. Analyses of picture elements and their relationships to current landscape variables indicate that children have a sophisticated understanding of their environment and how different environmental factors interact, either positively or negatively. Children appear to have landscape-dependent environmental perceptions, showing awareness of past environmental conditions and many aspects of recent trends, and translating these into predictions for future environmental conditions. The further removed their present landscape is from the originally forested one, the more environmental change they expect in the future, particularly declines in forest cover, rivers, animal diversity and increases in temperature and natural disasters. This suggests that loss of past perceptions and associated “shifting environmental baselines” do not feature strongly among children on Borneo, at least not for the perceptions we investigated here. Our findings that children have negative expectations of their future environmental conditions have important political implications. More than other generations, children have a stake in ensuring that future environmental conditions support their long-term well-being. Understanding what drives environmental views among children, and how they consider trade-offs between economic development and social and environmental change, should inform optimal policies on land use. Our study illuminates part of the complex interplay between perceptions of land cover and land use change. Capturing the views of children through artistic expressions provides a potentially powerful tool to influence public and political opinions, as well as a valuable approach for developing localized education and nature conservation programs. PMID:25093658

A refined ecological risk assessment for California red-legged frog, Delta smelt, and California tiger salamander exposed to malathion.

PubMed

Clemow, Yvonne H; Manning, Gillian E; Breton, Roger L; Winchell, Michael F; Padilla, Lauren; Rodney, Sara I; Hanzas, John P; Estes, Tammara L; Budreski, Katherine; Toth, Brent N; Hill, Katie L; Priest, Colleen D; Teed, R Scott; Knopper, Loren D; Moore, Dwayne Rj; Stone, Christopher T; Whatling, Paul

2018-03-01

The California red-legged frog (CRLF), Delta smelt (DS), and California tiger salamander (CTS) are 3 species listed under the United States Federal Endangered Species Act (ESA), all of which inhabit aquatic ecosystems in California. The US Environmental Protection Agency (USEPA) has conducted deterministic screening-level risk assessments for these species potentially exposed to malathion, an organophosphorus insecticide and acaricide. Results from our screening-level analyses identified potential risk of direct effects to DS as well as indirect effects to all 3 species via reduction in prey. Accordingly, for those species and scenarios in which risk was identified at the screening level, we conducted a refined probabilistic risk assessment for CRLF, DS, and CTS. The refined ecological risk assessment (ERA) was conducted using best available data and approaches, as recommended by the 2013 National Research Council (NRC) report "Assessing Risks to Endangered and Threatened Species from Pesticides." Refined aquatic exposure models including the Pesticide Root Zone Model (PRZM), the Vegetative Filter Strip Modeling System (VFSMOD), the Variable Volume Water Model (VVWM), the Exposure Analysis Modeling System (EXAMS), and the Soil and Water Assessment Tool (SWAT) were used to generate estimated exposure concentrations (EECs) for malathion based on worst-case scenarios in California. Refined effects analyses involved developing concentration-response curves for fish and species sensitivity distributions (SSDs) for fish and aquatic invertebrates. Quantitative risk curves, field and mesocosm studies, surface-water monitoring data, and incident reports were considered in a weight-of-evidence approach. Currently, labeled uses of malathion are not expected to result in direct effects to CRLF, DS or CTS, or indirect effects due to effects on fish and invertebrate prey. Integr Environ Assess Manag 2018;14:224-239. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC). © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Qichun; Zhang, Xuesong; Xu, Xingya

Riverine carbon cycling is an important, but insufficiently investigated component of the global carbon cycle. Analyses of environmental controls on riverine carbon cycling are critical for improved understanding of mechanisms regulating carbon processing and storage along the terrestrial-aquatic continuum. Here, we compile and analyze riverine dissolved organic carbon (DOC) concentration data from 1402 United States Geological Survey (USGS) gauge stations to examine the spatial variability and environmental controls of DOC concentrations in the United States (U.S.) surface waters. DOC concentrations exhibit high spatial variability, with an average of 6.42 ± 6.47 mg C/ L (Mean ± Standard Deviation). In general,more » high DOC concentrations occur in the Upper Mississippi River basin and the Southeastern U.S., while low concentrations are mainly distributed in the Western U.S. Single-factor analysis indicates that slope of drainage areas, wetlands, forests, percentage of first-order streams, and instream nutrients (such as nitrogen and phosphorus) pronouncedly influence DOC concentrations, but the explanatory power of each bivariate model is lower than 35%. Analyses based on the general multi-linear regression models suggest DOC concentrations are jointly impacted by multiple factors. Soil properties mainly show positive correlations with DOC concentrations; forest and shrub lands have positive correlations with DOC concentrations, but urban area and croplands demonstrate negative impacts; total instream phosphorus and dam density correlate positively with DOC concentrations. Notably, the relative importance of these environmental controls varies substantially across major U.S. water resource regions. In addition, DOC concentrations and environmental controls also show significant variability from small streams to large rivers, which may be caused by changing carbon sources and removal rates by river orders. In sum, our results reveal that general multi-linear regression analysis of twenty one terrestrial and aquatic environmental factors can partially explain (56%) the DOC concentration variation. In conclusion, this study highlights the complexity of the interactions among these environmental factors in determining DOC concentrations, thus calls for processes-based, non-linear methodologies to constrain uncertainties in riverine DOC cycling.« less

Plasma cortisol and faecal cortisol metabolites concentrations in stereotypic and non-stereotypic horses: do stereotypic horses cope better with poor environmental conditions?

PubMed Central

2013-01-01

Background Stereotypic behaviours, i.e. repetitive behaviours induced by frustration, repeated attempts to cope and/or brain dysfunction, are intriguing as they occur in a variety of domestic and captive species without any clear adaptive function. Among the different hypotheses, the coping hypothesis predicts that stereotypic behaviours provide a way for animals in unfavourable environmental conditions to adjust. As such, they are expected to have a lower physiological stress level (glucocorticoids) than non-stereotypic animals. Attempts to link stereotypic behaviours with glucocorticoids however have yielded contradictory results. Here we investigated correlates of oral and motor stereotypic behaviours and glucocorticoid levels in two large samples of domestic horses (NStudy1 = 55, NStudy2 = 58), kept in sub-optimal conditions (e.g. confinement, social isolation), and already known to experience poor welfare states. Each horse was observed in its box using focal sampling (study 1) and instantaneous scan sampling (study 2). Plasma samples (collected in study 1) but also non-invasive faecal samples (collected in both studies) were retrieved in order to assess cortisol levels. Results Results showed that 1) plasma cortisol and faecal cortisol metabolites concentrations did not differ between horses displaying stereotypic behaviours and non-stereotypic horses and 2) both oral and motor stereotypic behaviour levels did not predict plasma cortisol or faecal cortisol metabolites concentrations. Conclusions Cortisol measures, collected in two large samples of horses using both plasma sampling as well as faecal sampling (the latter method minimizing bias due to a non-invasive sampling procedure), therefore do not indicate that stereotypic horses cope better, at least in terms of adrenocortical activity. PMID:23289406

Hair and toenail arsenic concentrations of residents living in areas with high environmental arsenic concentrations.

PubMed Central

Hinwood, Andrea L; Sim, Malcolm R; Jolley, Damien; de Klerk, Nick; Bastone, Elisa B; Gerostamoulos, Jim; Drummer, Olaf H

2003-01-01

Surface soil and groundwater in Australia have been found to contain high concentrations of arsenic. The relative importance of long-term human exposure to these sources has not been established. Several studies have investigated long-term exposure to environmental arsenic concentrations using hair and toenails as the measure of exposure. Few have compared the difference in these measures of environmental sources of exposure. In this study we aimed to investigate risk factors for elevated hair and toenail arsenic concentrations in populations exposed to a range of environmental arsenic concentrations in both drinking water and soil as well as in a control population with low arsenic concentrations in both drinking water and soil. In this study, we recruited 153 participants from areas with elevated arsenic concentrations in drinking water and residential soil, as well as a control population with no anticipated arsenic exposures. The median drinking water arsenic concentrations in the exposed population were 43.8 micro g/L (range, 16.0-73 micro g/L) and median soil arsenic concentrations were 92.0 mg/kg (range, 9.1-9,900 mg/kg). In the control group, the median drinking water arsenic concentration was below the limit of detection, and the median soil arsenic concentration was 3.3 mg/kg. Participants were categorized based on household drinking water and residential soil arsenic concentrations. The geometric mean hair arsenic concentrations were 5.52 mg/kg for the drinking water exposure group and 3.31 mg/kg for the soil exposure group. The geometric mean toenail arsenic concentrations were 21.7 mg/kg for the drinking water exposure group and 32.1 mg/kg for the high-soil exposure group. Toenail arsenic concentrations were more strongly correlated with both drinking water and soil arsenic concentrations; however, there is a strong likelihood of significant external contamination. Measures of residential exposure were better predictors of hair and toenail arsenic concentrations than were local environmental concentrations. PMID:12573904

Atmospheric Gas Concentrations in the pre- and post-production Phases of an Unconventional Oil and Gas Recovery Operation at the MSEEL Test Site, West Virginia

NASA Astrophysics Data System (ADS)

Williams, J. P.; Reeder, M.; Pekney, N.; Osborne, J.; Risk, D. A.; McCawley, M.

2016-12-01

The Marcellus Shale Energy and Environment Laboratory (MSEEL) in West Virginia provides a unique opportunity in the field of unconventional energy research. By studying near-surface atmospheric chemistry over several phases of a hydraulic fracturing event, the project will help evaluate the impact of current practices, as well as new techniques and mitigation technologies. A total of 10 mobile surveys were conducted around the MSEEL site that contains 3 test wells (1 science well and 2 natural gas producing wells) and over several miles of nearby regional routes. Our surveying technique involved using a vehicle-mounted Los Gatos Research Ultraportable Methane/Acetylene Analyzer that provided geo-located measurements of methane (CH4) and carbon dioxide (CO2). The ratios of super-ambient concentrations of CO2 and CH4 were used to separate drilling- and fracturing-related observations from the natural background concentrations over the various well pad developmental stages. We found that regional background methane concentrations were elevated in all surveys, with a mean concentration of 3.21ppm (n = 99376), which simply reflected the mix of anthropogenic and natural CH4 sources in this riverine urban location. Over time and through successive stages of well development, we noted a progressive rise in the occurrence of enriched methane in the vicinity of the developed wells. While there was a moderate degree of variability over time, we did observe a higher occurrence of CH4-enriched observations during and after production began at the test site ( 25% of measurements within 500 meters of the test wells) compared to the baseline surveys (>10% of measurements). This change was expected, as we anticipated some level of increased emissions from the well pads as production began. However, we did not expect the rise to be so noticeable. The results of this study show that there is a statistically significant increase in the occurrence of enriched methane values in the vicinity of the well locations when we compare pre-production to post-production surveys, and that pre-existing methane sources in the immediate vicinity must be accounted for when assessing environmental impacts.

Seeing Colors: Cultural and Environmental Influences on Episodic Memory.

PubMed

Persaud, Kimele; Hemmer, Pernille; Kidd, Celeste; Piantadosi, Steven

2017-01-01

Expectations learned from our perceptual experiences, culture, and language can shape how we perceive, interact with, and remember features of the past. Here, we questioned whether environment also plays a role. We tested recognition memory for color in Bolivia's indigenous Tsimanè people, who experience a different color environment than standard U.S. We found that memory regressed differently between the groups, lending credence to the idea that environmental variations engender differences in expectations, and in turn perceptual memory for color.

Design considerations for combined radiation effects facilities for twelve year outer planet spacecraft voyages

NASA Technical Reports Server (NTRS)

Miller, C. G.

1972-01-01

The design considerations influencing the choice and utility of environmental simulation methods and facilities are described, insofar as they relate to the requirements imposed on outer planet spacecraft because of radiation environments to be expected. Possible means for duplicating the radioisotope thermoelectric generator radiation environment, and for duplicating the effects of the trapped radiation belt environment are described, together with an assessment of radiation levels to be expected in the vicinity of an environmental testing chamber when in use.

Inhalation of environmental stressors & chronic inflammation: autoimmunity and neurodegeneration.

PubMed

Gomez-Mejiba, Sandra E; Zhai, Zili; Akram, Hammad; Pye, Quentin N; Hensley, Kenneth; Kurien, Biji T; Scofield, R Hal; Ramirez, Dario C

2009-03-31

Human life expectancy and welfare has decreased because of the increase in environmental stressors in the air. An environmental stressor is a natural or human-made component present in our environment that upon reaching an organic system produces a coordinated response. This response usually involves a modification of the metabolism and physiology of the system. Inhaled environmental stressors damage the airways and lung parenchyma, producing irritation, recruitment of inflammatory cells, and oxidative modification of biomolecules. Oxidatively modified biomolecules, their degradation products, and adducts with other biomolecules can reach the systemic circulation, and when found in higher concentrations than normal they are considered to be biomarkers of systemic oxidative stress and inflammation. We classify them as metabolic stressors because they are not inert compounds; indeed, they amplify the inflammatory response by inducing inflammation in the lung and other organs. Thus the lung is not only the target for environmental stressors, but it is also the source of a number of metabolic stressors that can induce and worsen pre-existing chronic inflammation. Metabolic stressors produced in the lung have a number of effects in tissues other than the lung, such as the brain, and they can also abrogate the mechanisms of immunotolerance. In this review, we discuss recent published evidence that suggests that inflammation in the lung is an important connection between air pollution and chronic inflammatory diseases such as autoimmunity and neurodegeneration, and we highlight the critical role of metabolic stressors produced in the lung. The understanding of this relationship between inhaled environmental pollutants and systemic inflammation will help us to: (1) understand the molecular mechanism of environment-associated diseases, and (2) find new biomarkers that will help us prevent the exposure of susceptible individuals and/or design novel therapies.

Spatial variability of total carbon and soil organic carbon in agricultural soils in Baranja region, Croatia

NASA Astrophysics Data System (ADS)

Bogunović, Igor; Trevisani, Sebastiano; Pereira, Paulo; Šeput, Miranda

2017-04-01

Climate change is expected to have an important influence on the crop production in agricultural regions. Soil carbon represents an important soil property that contributes to mitigate the negative influence of climate change on intensive cropped areas. Based on 5063 soil samples sampled from soil top layer (0-30 cm) we studied the spatial distribution of total carbon (TC) and soil organic carbon (SOC) content in various soil types (Anthrosols, Cambisols, Chernozems, Fluvisols, Gleysols, Luvisols) in Baranja region, Croatia. TC concentrations ranged from 2.10 to 66.15 mg/kg (with a mean of 16.31 mg/kg). SOC concentrations ranged from 1.86 to 58.00 mg/kg (with a mean of 13.35 mg/kg). TC and SOC showed moderate heterogeneity with coefficient of variation (CV) of 51.3% and 33.8%, respectively. Average concentrations of soil TC vary in function of soil types in the following decreasing order: Anthrosols (20.9 mg/kg) > Gleysols (19.3 mg/kg) > Fluvisols (15.6 mg/kg) > Chernozems (14.2 mg/kg) > Luvisols (12.6 mg/kg) > Cambisols (11.1 mg/kg), while SOC concentrations follow next order: Gleysols (15.4 mg/kg) > Fluvisols (13.2 mg/kg) = Anthrosols (13.2 mg/kg) > Chernozems (12.6 mg/kg) > Luvisols (11.4 mg/kg) > Cambisols (10.5 mg/kg). Performed geostatistical analysis of TC and SOC; both the experimental variograms as well as the interpolated maps reveal quite different spatial patterns of the two studied soil properties. The analysis of the spatial variability and of the spatial patterns of the produced maps show that SOC is likely influenced by antrophic processes. Spatial variability of SOC indicates soil health deterioration on an important significant portion of the studied area; this suggests the need for future adoption of environmentally friendly soil management in the Baranja region. Regional maps of TC and SOC provide quantitative information for regional planning and environmental monitoring and protection purposes.

Critical assessment of the ubiquitous occurrence and fate of the insect repellent N,N-diethyl-m-toluamide in water.

PubMed

Merel, Sylvain; Snyder, Shane A

2016-11-01

The insect repellent diethyltoluamide (DEET) is among the most frequently detected organic chemical contaminants in water across a wide range of geographies from around the world. These observations are raising critical questions and increasing concerns regarding potential environmental relevance, particularly when the emergence of severe neurological conditions attributed to the Zika virus has increased the use of insect repellents. After dermal application, DEET is washed from the skin when bathing and enters the municipal sewer system before discharge into the environment. Mainly measured by gas chromatography or liquid chromatography coupled to mass spectrometry (GC-MS or LC-MS), more than 200 peer-reviewed publications have already reported concentrations of DEET ranging ng/L to mg/L in several water matrices from North America, Europe, Asia, Oceania, and more recently Africa and South America. While conventional wastewater treatment technology has limited capacity of removal, advanced technologies are capable of better attenuation and could lower the environmental discharge of organic contaminants, including DEET. For instance, adsorption on activated carbon, desalinating membrane processes (nanofiltration and reverse osmosis), ozonation, and advanced oxidation processes can achieve 50% to essentially 100% DEET attenuation. Despite the abundant literature on the topic, the ubiquity of DEET in the environment still raises questions due to the apparent lack of obvious spatio-temporal trends in concentrations measured in surface water, which does not fit the expected usage pattern of insect repellents. Moreover, two recent studies showed discrepancies between the concentrations obtained by GC-MS and LC-MS analyses. While the occurrence of DEET in the environment is well established, the concentrations reported should be interpreted cautiously, considering the disparities in methodologies applied and occurrence patterns observed. Therefore, this manuscript provides a critical overview of the origin of DEET in the environment, the relevant analytical methods, the occurrence reported in peer-reviewed literature, and the attenuation efficacy of water treatment processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Chemical characterization and spatial distribution of PAHs and heavy hydrocarbons in rural sites of Campania Region, South Italy.

PubMed

Monaco, D; Riccio, A; Chianese, E; Adamo, P; Di Rosa, S; Fagnano, M

2015-10-01

In this paper, the behaviour and distribution patterns of heavy hydrocarbons and several polycyclic aromatic hydrocarbon (PAH) priority pollutants, as listed by the US Environmental Protection Agency, were evaluated in 891 soil samples. The samples were collected in three expected polluted rural sites in Campania (southern Italy) as part of the LIFE11 ECOREMED project, funded by the European Commission, to test innovative agriculture-based soil restoration techniques. These sites have been selected because they have been used for the temporary storage of urban and building waste (Teverola), subject to illicit dumping of unknown material (Trentola-Ducenta), or suspected to be polluted by metals due to agricultural practices (Giugliano). Chemical analysis of soil samples allowed the baseline pollution levels to be determined prior to any intervention. It was found that these areas can be considered contaminated for residential use, in accordance with Italian environmental law (Law Decree 152/2006). Statistical analysis applied to the data proved that average mean concentrations of heavy hydrocarbons could be as high as 140 mg/kg of dry soil with peaks of 700 mg/kg of dry soil, for the Trentola-Ducenta site; the median concentration of analytical results for hydrocarbon (HC) concentration for the Trentola-Ducenta and Giugliano sites was 63 and 73.4 mg/kg dry soil, respectively; for Teverola, the median level was 35 mg/kg dry soil. Some PAHs (usually benzo(a)pyrene) also exceeded the maximum allowed level in all sites. From the principal component analysis applied to PAH concentrations, it emerged that pollutants can be supposed to derive from a single source for the three sites. Diagnostic ratios calculated to determine possible PAH sources suggest petroleum combustion or disposal practice. Our sampling protocol also showed large dishomogeneity in soil pollutant spatial distribution, even at a scale as small as 3.3 m, indicating that variability could emerge at very short spatial scales.

76 FR 59395 - Notice of Webcast Meeting of the Environmental Financial Advisory Board (EFAB)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-26

... creative approaches to funding environmental programs, projects, and activities. The purpose of the meeting... priorities and to discuss progress with work projects under EFAB's current Strategic Action Agenda; and... topics expected to be discussed include: financing clean air technology; financing tribal environmental...

Dynamic Probabilistic Modeling of Environmental Emissions of Engineered Nanomaterials.

PubMed

Sun, Tian Yin; Bornhöft, Nikolaus A; Hungerbühler, Konrad; Nowack, Bernd

2016-05-03

The need for an environmental risk assessment for engineered nanomaterials (ENM) necessitates the knowledge about their environmental concentrations. Despite significant advances in analytical methods, it is still not possible to measure the concentrations of ENM in natural systems. Material flow and environmental fate models have been used to provide predicted environmental concentrations. However, almost all current models are static and consider neither the rapid development of ENM production nor the fact that many ENM are entering an in-use stock and are released with a lag phase. Here we use dynamic probabilistic material flow modeling to predict the flows of four ENM (nano-TiO2, nano-ZnO, nano-Ag and CNT) to the environment and to quantify their amounts in (temporary) sinks such as the in-use stock and ("final") environmental sinks such as soil and sediment. Caused by the increase in production, the concentrations of all ENM in all compartments are increasing. Nano-TiO2 had far higher concentrations than the other three ENM. Sediment showed in our worst-case scenario concentrations ranging from 6.7 μg/kg (CNT) to about 40 000 μg/kg (nano-TiO2). In most cases the concentrations in waste incineration residues are at the "mg/kg" level. The flows to the environment that we provide will constitute the most accurate and reliable input of masses for environmental fate models which are using process-based descriptions of the fate and behavior of ENM in natural systems and rely on accurate mass input parameters.

Assessment of Fish Habitat, Water Quality, and Selected Contaminants in Streambed Sediments in Noyes Slough, Fairbanks, Alaska, 2001-2002

USGS Publications Warehouse

Kennedy, Ben W.; Whitman, Matthew S.; Burrows, Robert L.; Richmond, Sharon A.

2004-01-01

During 2001-2002, the U.S. Geological Survey sampled streambed sediment at 23 sites, measured water quality at 26 sites, and assessed fish habitat for the entire length of Noyes Slough, a 5.5-mile slough of the Chena River in Fairbanks, Alaska. These studies were undertaken to document the environmental condition of the slough and to provide information to the public for consideration in plans to improve environmental conditions of the waterway. The availability of physical habitat for fish in the slough does not appear to be limited, although some beaver dams and shallow water may restrict movement, particularly during low flow. Elevated water temperatures in summer and low dissolved-oxygen concentrations are the principle factors adversely affecting water quality in Noyes Slough. Increased flow mitigated poor water-quality conditions and reduced the number of possible fish barriers. Flow appears to be the most prominent mechanism shaping water quality and fish habitat in Noyes Slough. Streambed sediment samples collected at 23 sites in 2001 were analyzed for 24 trace elements. Arsenic, lead, and zinc were the only trace elements detected in concentrations that exceed probable effect levels for the protection of aquatic life. The background concentration for arsenic in Noyes Slough is naturally elevated because of significant concentrations of arsenic in local bedrock and ground water. Sources of the zinc and lead contamination are uncertain, however both lead and zinc are common urban contaminants. Streambed-sediment samples from 12 sites in 2002 were analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), and semivolatile organic compounds (SVOCs). The concentration of bis(2-ethylhexyl)phthalate of 2,600 micrograms per kilogram (?g/kg) for one sample from the site above Aurora Drive approached the aquatic-life criterion of 2,650 ?g/kg. Low concentrations of p-cresol, chrysene, and fluoranthene were detected in most of the sediment samples. The presence of these compounds in Noyes Slough sediment was expected because cresols are emitted to the atmosphere in the exhaust from motor vehicles and chrysene and fluoranthene are formed during the incomplete burning of coal, oil, gas, wood, garbage, or other organic substances. Low-level concentrations of DDT or its degradation products DDD and DDE were detected in all samples collected during 2002. However, total DDT (DDT+DDD+DDE) concentrations are less than the effects range median aquatic-life criterion of 46.1 ?g/kg. In general, total DDT concentrations were less than 10 ?g/kg, except for samples from two sites that have estimated concentrations of about 14 and 20 ?g/kg.

The influence of environment on the properties of galaxies

NASA Astrophysics Data System (ADS)

Hashimoto, Yasuhiro

1999-11-01

I will present the result of the evaluation of the environmental influences on three important galactic properties; morphology, star formation rate, and interaction in the local universe. I have used a very large and homogeneous sample of 15749 galaxies drawn from the Las Campanas Redshift Survey (Shectman et al. 1996). This data set consists of galaxies inhabiting the entire range of galactic environments, from the sparsest field to the densest clusters, thus allowing me to study environmental variations without combing multiple data sets with inhomogeneous characteristics. Furthermore, I can also extend the research to a ``general'' environmental investigation by, for the first time, decoupling the very local environment, as characterized by local galaxy density, from the effects of larger-scale environments, such as membership in a cluster. The star formation rate is characterized by the strength of EW(OII), while the galactic morphology is characterized by the automatically-measured concentration index (e.g. Okamura, Kodaira, & Watanabe 1984), which is more closely related to the bulge-to-disk ratio of galaxies than Hubble type, and is therefore expected to behave more independently on star formation activity in a galaxy. On the other hand, the first systematic quantitative investigation of the environmental influence on the interaction of galaxies is made by using two automatically-determined objective measures; the asymmetry index and existence of companions. The principal conclusions of this work are: (1)The concentration of the galactic light profile (characterized by the concentration index) is predominantly correlated with the relatively small-scale environment which is characterized by the local galaxy density. (2)The star formation rate of galaxies (characterized by the EW(OII)) is correlated both with the small-scale environment (the local galaxy density) and the larger scale environment which is characterized by the cluster membership. For weakly star forming galaxies, the star formation rate is correlated both with the local galaxy density and rich cluster membership. It also shows a correlation with poor cluster membership. For strongly star forming galaxies, the star formation rate is correlated with the local density and the poor cluster membership. (3)Interacting galaxies (characterized by the asymmetry index and/or the existence of apparent companions) show no correlation with rich cluster membership, but show a fair to strong correlation with the poor cluster membership.

Microfluidic acoustophoretic force based low-concentration oil separation and detection from the environment.

PubMed

Wang, Han; Liu, Zhongzheng; Kim, Sungman; Koo, Chiwan; Cho, Younghak; Jang, Dong-Young; Kim, Yong-Joe; Han, Arum

2014-03-07

Detecting and quantifying extremely low concentrations of oil from the environment have broad applications in oil spill monitoring in ocean and coastal areas as well as in oil leakage monitoring on land. Currently available methods for low-concentration oil detection are bulky or costly with limited sensitivities. Thus they are difficult to be used as portable and field-deployable detectors in the case of oil spills or for monitoring the long-term effects of dispersed oil on marine and coastal ecosystems. Here, we present a low-concentration oil droplet trapping and detection microfluidic system based on the acoustophoresis phenomenon where oil droplets in water having a negative acoustic contrast factor move towards acoustic pressure anti-nodes. By trapping oil droplets from water samples flowing through a microfluidic channel, even very low concentrations of oil droplets can be concentrated to a detectable level for further analyses, which is a significant improvement over currently available oil detection systems. Oil droplets in water were successfully trapped and accumulated in a circular acoustophoretic trapping chamber of the microfluidic device and detected using a custom-built compact fluorescent detector based on the natural fluorescence of the trapped crude oil droplets. After the on-line detection, crude oil droplets released from the trapping chamber were successfully separated into a collection outlet by acoustophoretic force for further off-chip analyses. The developed microfluidic system provides a new way of trapping, detecting, and separating low-concentration crude oil from environmental water samples and holds promise as a low-cost field-deployable oil detector with extremely high sensitivity. The microfluidic system and operation principle are expected to be utilized in a wide range of applications where separating, concentrating, and detecting small particles having a negative acoustic contrast factor are required.

Dissolved Oxygen (DO) and Nutrients Analysis in the Río Piedras River, San Juan, Puerto Rico

NASA Astrophysics Data System (ADS)

Santiago, I.; Infante, G.

2016-02-01

The Río Piedras is the only River in the metropolitan area of Puerto Rico. This River was the first water supplier and is part of the ancient aqueduct, the first treatment plant of the San Juan urban area. Because of its cultural and historic importance the ancient aqueduct was cataloged as a National Treasure by the National Trust of History Preservation in 2014. Actually, is protected by Para La Naturaleza (before named in Spanish as the "Fideicomiso de Conservación de Puerto Rico"). The research objectives were to evaluate and measure the dissolved oxygen (DO), total phosphorus (TP) and the heavy metals (HM) concentrations of the River. Also, to examine if the DO, TP and HM (Cu, Fe, Pb, Mn, Al, and Zn) concentrations were in compliance with the Environmental Protection Agency (EPA) standards. Using DO bottles, water samples were collected on three points during six dates. DO concentrations were measured with the YSI Pro GBOD. TP concentrations were analyzed using the UV-Vis spectrophotometer "HACH" (DR 5000). Utilizing the ICP (Inductively Coupled Plasma) spectrophotometer emission technique and the EPA protocols HM concentrations were measured. Preliminary results show that the DO measurements were from 5.00 mg/L to 7.00 mg/L (p-value=0.282). HM concentrations findings were 0.456 (correlation coefficient=0.9997), 1.205 (correlation coefficient=0.9972) and 3.287 (correlation coefficient=0.9950) for Zn, Cu and Cr, respectively. We expected highest HM concentrations in our finals results due to the drought weather during each samples collection. Data analysis for DO, TP and HM concentrations will be presented. Finally, the results obtained and the project details will be explained during the poster presentation.

Pre-Trip Expectations and Post-Trip Satisfaction with Marine Tour Interpretation in Hawaii: Applying the Norm Activation Model

ERIC Educational Resources Information Center

Littlejohn, Kerrie; Needham, Mark D.; Szuster, Brian W.; Jordan, Evan J.

2016-01-01

This article examines environmental education by focusing on recreationist expectations for interpretation on marine tours, satisfaction with this interpretation and whether expectations were met, and how these perceptions correlate with components of the norm activation model. Recreationists surveyed before and after tours to Molokini, Hawaii (n…

Functional effects of the bacterial insecticide Bacillus thuringiensis var. kurstaki on aquatic microbial communities.

PubMed

Kreutzweiser, D P; Gringorten, J L; Thomas, D R; Butcher, J T

1996-04-01

Epilithic microbial communities were colonized on leaf disks and exposed to commercial preparations of Bacillus thuringiensis var. kurstaki (Btk) in aquatic microcosms. Responses in terms of microbial respiration, bacterial cell density, protozoan density, and microbial decomposition activity were measured. Test concentrations for treatments with Dipel 64AF and Dipel 8AF in microcosms were the expected environmental concentration (EEC) of 20 IU/ml, 100x the EEC, and 1000x the EEC. Bacterial cell density in the biofilm of leaf disks was significantly increased at concentrations as low as the EEC. There were no concomitant alterations in protozoan density. Microbial respiration was significantly increased, and decomposition activity was significantly decreased, but only at the artificially high concentration of 1000x the EEC. This effect was attributed to the spore-crystal component rather than formulation ingredients. Microbial decomposition of leaf material was also determined in outdoor stream channels treated at concentrations ranging from the EEC to 100x the EEC. Although there tended to be reduced decomposition activity in treated channels, there were no significant differences in mass loss of leaf material between treated and control channels. Various regression, classification, and ordination procedures were applied to the experimental data, and none indicated significant treatment effects. These results from laboratory and controlled field experiments indicate that contamination of watercourses with Btk is unlikely to result in significant adverse effects on microbial community function in terms of detrital decomposition.

Development of an inhalation unit risk factor for isoprene.

PubMed

Haney, Joseph T; Phillips, Tracie; Sielken, Robert L; Valdez-Flores, Ciriaco

2015-12-01

A unit risk factor (URF) was developed for isoprene based on evaluation of three animal studies with adequate data to perform dose-response modeling (NTP, 1994, 1999; Placke et al., 1996). Ultimately, the URF of 6.2E-08 per ppb (2.2E-08 per μg/m(3)) was based on the 95% lower confidence limit on the effective concentration corresponding to 10% extra risk for liver carcinoma in male B6C3F1 mice after incorporating appropriate adjustment factors for species differences in target tissue metabolite concentrations and inhalation dosimetry. The corresponding lifetime air concentration at the 1 in 100,000 no significant excess risk level is 160 ppb (450 μg/m(3)). This concentration is almost 4400 times lower than the lowest exposure level associated with statistically increased liver carcinoma in B6C3F1 mice in the key study (700 ppm in Placke et al., 1996) and is above typical isoprene breath concentrations reported in the scientific literature. Continuous lifetime environmental exposure to the 1 in 100,000 excess risk level of 160 ppb would be expected to raise the human blood isoprene area under the curve (AUC) less than one-third of the standard deviation of the endogenous mean blood AUC. The mean for ambient air monitoring sites in Texas (2005-2014) is approximately 0.13 ppb. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Use of a Concentration Game for Environmental Chemistry Class Review

ERIC Educational Resources Information Center

Nowosielski, Danica A.

2007-01-01

The concentration game can be used as a complete class or a portion of it to help reinforce the material being presented or for review sessions. An environmental chemistry class review is presented with the use of the concentration game.

Phosphorus Concentrations in Stream-Water and Reference Samples - An Assessment of Laboratory Comparability

USGS Publications Warehouse

McHale, Michael R.; McChesney, Dennis

2007-01-01

In 2003, a study was conducted to evaluate the accuracy and precision of 10 laboratories that analyze water-quality samples for phosphorus concentrations in the Catskill Mountain region of New York State. Many environmental studies in this region rely on data from these different laboratories for water-quality analyses, and the data may be used in watershed modeling and management decisions. Therefore, it is important to determine whether the data reported by these laboratories are of comparable accuracy and precision. Each laboratory was sent 12 samples for triplicate analysis for total phosphorus, total dissolved phosphorus, and soluble reactive phosphorus. Eight of these laboratories reported results that met comparability criteria for all samples; the remaining two laboratories met comparability criteria for only about half of the analyses. Neither the analytical method used nor the sample concentration ranges appeared to affect the comparability of results. The laboratories whose results were comparable gave consistently comparable results throughout the concentration range analyzed, and the differences among methods did not diminish comparability. All laboratories had high data precision as indicated by sample triplicate results. In addition, the laboratories consistently reported total phosphorus values greater than total dissolved phosphorus values, and total dissolved phosphorus values greater than soluble reactive phosphorus values, as would be expected. The results of this study emphasize the importance of regular laboratory participation in sample-exchange programs.

Environmental factors associated with long-term changes in chlorophyll concentration in the Sacramento-San Joaquin delta and Suisun Bay, California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lehman, P.W.

Long-term changes in chlorophyll concentration were predicted from environmental variables using Box-Jenkins transfer function models for the Sacramento and San Joaquin rivers and Suisun Bay. The indication that oceanic phytoplankton biomass for the California regions is associated with climatic phenomena produced by El Nino and the Southern Oscillation (ENSO) was one of several factors used to standardize the dataset. Data used for the analyses were collected continuously on a semimonthly or monthly basis over the 17-yr period between 1971 and 1987. Groups of highly correlated environmental variables were summarized along three environmental axes using principal component analysis. The first environmentalmore » axis summarized river flow and specific conductance. The second environmental axis summarized water transparency and the third environmental axis summarized air and water temperature. Chlorophyll concentration was significantly cross-correlated with environmental axes and individual environmental variables. Transfer function models developed to describe changes in chlorophyll concentration over time were characterized by lag responses and described between 41% and 51% of the data variation. Significant cross-correlations between environmental axes and the California climate index (CA SLP) were used to develop a conceptual model of the link between regional climate and estuarine production. 50 refs., 5 figs.« less

Correlation between concentrations of n-hexane and toluene in exhaled and environmental air in an occupationally exposed population.

PubMed

Periago, J F; Morente, A; Villanueva, M; Luna, A

1994-01-01

We determined the correlations between the concentrations of n-hexane and toluene in exhaled and environmental air in the shoe manufacturing industry. Data were collected in 1988 and in 1992 from a total of 265 subjects. Environmental air samples were collected with personal diffusive samplers by adsorption on activated charcoal during exposure and from end-expired air (alveolar air) on cartridges of activated charcoal after exposure. Both compounds were desorbed with carbon disulphide and analysed by gas chromatography. Linear regression analyses showed a good correlation between environmental and end-expired air concentrations (r = 0.82 for n-hexane and r = 0.81 for toluene). These correlations allowed us to calculate the concentrations in expired air corresponding to current environmental limit values. The calculated concentrations in end-expired air that correspond to current environmental threshold limit values of 176 mg m-3 for n-hexane and 377 mg m-3 for toluene are 28 mg m-3 (95% confidence limit, 27-29 mg m-3) and 40 mg m-3 (95% confidence limit, 39-41 mg m-3), respectively. Similar correlations were found when the data from the two study periods were analysed separately.

Degradation and environmental risk of surfactants after the application of compost sludge to the soil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gonzalez, M.M.; Martin, J.; Camacho-Munoz, D.

2012-07-15

Highlights: Black-Right-Pointing-Pointer Degradation of surfactants in soil amended with sewage sludge during 100 days. Black-Right-Pointing-Pointer Temperature influences on the degradation of the studied compounds. Black-Right-Pointing-Pointer Overall, the LAS degradation is faster than the NP compounds degradation. Black-Right-Pointing-Pointer Therefore, the LAS presented lower environmental risk than the NP compounds. - Abstract: In this work, the degradation of anionic and non-ionic surfactants in agricultural soil amended with sewage sludge is reported. The compounds analysed were: linear alkylbenzene sulphonates (LAS) with a 10-13 carbon alkylic chain, and nonylphenolic compounds (NPE), including nonylphenol (NP) and nonylphenol ethoxylates with one and two ethoxy groups (NP1EOmore » and NP2EO). The degradation studies were carried out under winter (12.7 Degree-Sign C) and summer (22.4 Degree-Sign C) conditions in Andalusia region. The concentration of LAS was reduced to 2% of the initial concentration 100 day after sludge-application to the soil. The half-life time measured for LAS homologues were ranged between 4 and 14 days at 12.7 Degree-Sign C and between 4 and 7 days at 22.4 Degree-Sign C. With regard to NPE compounds, after 8 and 4 days from the beginning of the experiment at 12.7 and 22.4 Degree-Sign C, respectively, their concentration levels were increased to 6.5 and 13.5 mg/kg dm (dry matter) as consequence of the degradation of nonylphenol polyethoxylates. These concentration levels were reduced to 5% after 63 and 70 days for 12.7 Degree-Sign C and 22.4 Degree-Sign C, respectively. The half-life times measured for NPEs were from 8 to 16 days at 12.7 Degree-Sign C and from 8 to 18 days at 22.4 Degree-Sign C. Environmental risk assessment revealed that for LAS homologues no environment risk could be expected after 7 and 8 days of sludge application to the soil for 22.4 and 12.7 Degree-Sign C, respectively; however, potential toxic effects could be observed for the nonylphenolic compounds during the first 56 days after sludge application to the soil.« less

55,000 yrs of Environmental Change in the Southern Hemisphere: Peat Stratigraphy and Inorganic Geochemistry of Lynch's Crater, NE Queensland, Australia.

NASA Astrophysics Data System (ADS)

Muller, J.; Kylander, M. E.; Wust, R. A.; Weiss, D. J.

2005-12-01

This study presents one of the first applications of geochemical proxies to define changes in vegetation, hydrology and atmospheric dust recorded in a peat deposit in the Southern Hemisphere. The Lynch's Crater archive has captured local, regional and global environmental changes and reveals dynamic ecosystem changes as a result of climate shifts over the past 55,000 yrs BP. The 13 m peat record consists of 1.5 m of ombrotrophic peat underlain by a minerotrophic peat. The ombrotrophic section consists of low inorganic content ("ash") and low pH, as expected in of an ombrotrophic environment. The minerotrophic section contains several layers, up to a few cm thick, where abundant sponge spicules, diatom fragments and detrital quartz are indicative of high algal and protista productivity. These layers are characterised by high (up to 50%) ash, indicating persistent flooding of the peat deposits of Lynch's Crater and signalling periods of change in precipitation in North Queensland, Australia. Geochemical data are used to differentiate between climatic episodes associated with flooding events and internal and external atmospheric dust fluxes. Lead isotopes with lithogenic and chalcophile elements tell us that two distinctive sources are prevalent in the Lynch's Crater record. Most of the inorganic fractions of the deposits have the same geochemical signatures as the rocks and sediments of the crater wall, with low As concentrations, high Al, Ti and Sc concentrations and a more radiogenic Pb isotope signature. Influence from long-range dust is distinguished in the lower sections of the core (~35,000-55,000 cal yrs BP) where increases in As concentrations and less radiogenic Pb isotopes are found. Leading up to the Holocene (~35,000-10,000) the influence of increased dust influx becomes more significant (increasing lithogenics, chalcophiles and ash content) and where possible long-range sources are still active, but diluted by a prevailing dominance of the local sources. During the Holocene Pb isotope signatures remain similar but lithogenic and chalcophile concentrations decrease significantly and coincide with the lowest ash values (~4%) in the core. The research shows Lynch's Crater is a sensitive record of past atmospheric dust cylces and precipitation regimes leading to an invaluable record of past environmental change in the Southern Hemisphere.

Acute toxic effects of endosulfan sulfate on three life stages of grass shrimp, Palaemonetes pugio.

PubMed

Key, Peter B; Chung, Katy W; Venturella, John J; Shaddrick, Brian; Fulton, Michael H

2010-01-01

In this study, the toxicity of endosulfan sulfate, the primary degradation product of the insecticide endosulfan, was determined in three life stages of the grass shrimp (Palaemonetes pugio). After 96 h exposure to endosulfan sulfate, the grass shrimp adult LC50 was 0.86 microg/L (95% CI 0.56-1.31), the grass shrimp larvae LC50 was 1.64 microg/L (95% CI 1.09-2.47) and the grass shrimp embryo LC50 was 45.85 microg/L (95% CI 23.72-88.61 microg/L). This was compared to the previously published grass shrimp 96-h LC50s for endosulfan. The toxicity of the two compounds was similar for the grass shrimp life stages with adults more sensitive than larvae and embryos. The presence of sediment in 24h endosulfan sulfate-exposures raised LC50s for both adult and larval grass shrimp but not significantly. The USEPA expected environmental concentrations (EEC) for total endosulfan and endosulfan sulfate and the calculations of risk quotients (RQ) based on the more sensitive adult grass shrimp 96-h LC50 clearly show that environmental concentrations equal to acute EECs would prove detrimental to grass shrimp or other similarly sensitive aquatic organisms. These results indicate that given the persistence and toxicity of endosulfan sulfate, future risk assessments should consider the toxicity potential of the parent compound as well as this degradation product.

Revolatilization of persistent organic pollutants in the Arctic induced by climate change

NASA Astrophysics Data System (ADS)

Ma, Jianmin; Hung, Hayley; Tian, Chongguo; Kallenborn, Roland

2011-08-01

Persistent organic pollutants (POPs) are organic compounds produced by human activities that are resistant to environmental degradation. They include industrial chemicals, such as polychlorinated biphenyls, and pesticides, such as dichlorodiphenyltrichloroethane. Owing to their persistence in the environment, POPs are transported long distances in the atmosphere, accumulating in regions such as the Arctic, where low temperatures induce their deposition. Here the compounds accumulate in wildlife and humans, putting their health at risk. The concentrations of many POPs have decreased in Arctic air over the past few decades owing to restrictions on their production and use. As the climate warms, however, POPs deposited in sinks such as water and ice are expected to revolatilize into the atmosphere, and there is evidence that this process may have already begun for volatile compounds. Here we show that many POPs, including those with lower volatilities, are being remobilized into the air from repositories in the Arctic region as a result of sea-ice retreat and rising temperatures. We analysed records of the concentrations of POPs in Arctic air since the early 1990s and compared the results with model simulations of the effect of climate change on their atmospheric abundances. Our results indicate that a wide range of POPs have been remobilized into the Arctic atmosphere over the past two decades as a result of climate change, confirming that Arctic warming could undermine global efforts to reduce environmental and human exposure to these toxic chemicals.

Conversion of iodide to hypoiodous acid and iodine in aqueous microdroplets exposed to ozone.

PubMed

Pillar, Elizabeth A; Guzman, Marcelo I; Rodriguez, Jose M

2013-10-01

Halides are incorporated into aerosol sea spray, where they start the catalytic destruction of ozone (O3) over the oceans and affect the global troposphere. Two intriguing environmental problems undergoing continuous research are (1) to understand how reactive gas phase molecular halogens are directly produced from inorganic halides exposed to O3 and (2) to constrain the environmental factors that control this interfacial process. This paper presents a laboratory study of the reaction of O3 at variable iodide (I(-)) concentration (0.010-100 μM) for solutions aerosolized at 25 °C, which reveal remarkable differences in the reaction intermediates and products expected in sea spray for low tropospheric [O3]. The ultrafast oxidation of I(-) by O3 at the air-water interface of microdroplets is evidenced by the appearance of hypoiodous acid (HIO), iodite (IO2(-)), iodate (IO3(-)), triiodide (I3(-)), and molecular iodine (I2). Mass spectrometry measurements reveal an enhancement (up to 28%) in the dissolution of gaseous O3 at the gas-liquid interface when increasing the concentration of NaI or NaBr from 0.010 to 100 μM. The production of iodine species such as HIO and I2 from NaI aerosolized solutions exposed to 50 ppbv O3 can occur at the air-water interface of sea spray, followed by their transfer to the gas-phase, where they contribute to the loss of tropospheric ozone.

Combined Effects of Deforestation and Doubled Atmospheric CO2 Concentrations on the Climate of Amazonia.

NASA Astrophysics Data System (ADS)

Costa, Marcos Heil; Foley, Jonathan A.

2000-01-01

It is generally expected that the Amazon basin will experience at least two major environmental changes during the next few decades and centuries: 1) increasing areas of forest will be converted to pasture and cropland, and 2) concentrations of atmospheric CO2 will continue to rise. In this study, the authors use the National Center for Atmospheric Research GENESIS atmospheric general circulation model, coupled to the Integrated Biosphere Simulator, to determine the combined effects of large-scale deforestation and increased CO2 concentrations (including both physiological and radiative effects) on Amazonian climate.In these simulations, deforestation decreases basin-average precipitation by 0.73 mm day1 over the basin, as a consequence of the general reduction in vertical motion above the deforested area (although there are some small regions with increased vertical motion). The overall effect of doubled CO2 concentrations in Amazonia is an increase in basin-average precipitation of 0.28 mm day1. The combined effect of deforestation and doubled CO2, including the interactions among the processes, is a decrease in the basin-average precipitation of 0.42 mm day1. While the effects of deforestation and increasing CO2 concentrations on precipitation tend to counteract one another, both processes work to warm the Amazon basin. The effect of deforestation and increasing CO2 concentrations both tend to increase surface temperature, mainly because of decreases in evapotranspiration and the radiative effect of CO2. The combined effect of deforestation and doubled CO2, including the interactions among the processes, increases the basin-average temperature by roughly 3.5°C.

Comprehensive probabilistic modelling of environmental emissions of engineered nanomaterials.

PubMed

Sun, Tian Yin; Gottschalk, Fadri; Hungerbühler, Konrad; Nowack, Bernd

2014-02-01

Concerns about the environmental risks of engineered nanomaterials (ENM) are growing, however, currently very little is known about their concentrations in the environment. Here, we calculate the concentrations of five ENM (nano-TiO2, nano-ZnO, nano-Ag, CNT and fullerenes) in environmental and technical compartments using probabilistic material-flow modelling. We apply the newest data on ENM production volumes, their allocation to and subsequent release from different product categories, and their flows into and within those compartments. Further, we compare newly predicted ENM concentrations to estimates from 2009 and to corresponding measured concentrations of their conventional materials, e.g. TiO2, Zn and Ag. We show that the production volume and the compounds' inertness are crucial factors determining final concentrations. ENM production estimates are generally higher than a few years ago. In most cases, the environmental concentrations of corresponding conventional materials are between one and seven orders of magnitude higher than those for ENM. Copyright © 2013 Elsevier Ltd. All rights reserved.

Inference for Environmental Intervention Studies using Principal Stratification

PubMed Central

Hackstadt, A. J.; Butz, Arlene M.; Williams, D’Ann L.; Diette, Gregory B.; Breysse, Patrick N.; Matsui, Elizabeth C.; Peng, Roger D.

2014-01-01

Previous research has found evidence of an association between indoor air pollution and asthma morbidity in children. Environmental intervention studies have been performed to examine the role of household environmental interventions in altering indoor air pollution concentrations and improving health. Previous environmental intervention studies have found only modest effects on health outcomes and it is unclear if the health benefits provided by environmental modification are comparable to those provided by medication. Traditionally, the statistical analysis of environmental intervention studies has involved performing two intention-to-treat analyses that separately estimate the effect of the environmental intervention on health and the effect of the environmental intervention on indoor air pollution concentrations. We propose a principal stratification (PS) approach to examine the extent to which an environmental intervention’s effect on health outcomes coincides with its effect on indoor air pollution. We apply this approach to data from a randomized air cleaner intervention trial conducted in a population of asthmatic children living in Baltimore, Maryland, USA. We find that amongst children for whom the air cleaner reduced indoor particulate matter concentrations, the intervention resulted in a meaningful improvement of asthma symptoms with an effect generally larger than previous studies have shown. A key benefit of using principal stratification in environmental intervention studies is that it allows investigators to estimate causal effects of the intervention for sub-groups defined by changes in the indoor air pollution concentration. PMID:25164949

Inference for environmental intervention studies using principal stratification.

PubMed

Hackstadt, Amber J; Matsui, Elizabeth C; Williams, D'Ann L; Diette, Gregory B; Breysse, Patrick N; Butz, Arlene M; Peng, Roger D

2014-12-10

Previous research has found evidence of an association between indoor air pollution and asthma morbidity in children. Environmental intervention studies have been performed to examine the role of household environmental interventions in altering indoor air pollution concentrations and improving health. Previous environmental intervention studies have found only modest effects on health outcomes and it is unclear if the health benefits provided by environmental modification are comparable with those provided by medication. Traditionally, the statistical analysis of environmental intervention studies has involved performing two intention-to-treat analyses that separately estimate the effect of the environmental intervention on health and the effect of the environmental intervention on indoor air pollution concentrations. We propose a principal stratification approach to examine the extent to which an environmental intervention's effect on health outcomes coincides with its effect on indoor air pollution. We apply this approach to data from a randomized air cleaner intervention trial conducted in a population of asthmatic children living in Baltimore, Maryland, USA. We find that among children for whom the air cleaner reduced indoor particulate matter concentrations, the intervention resulted in a meaningful improvement of asthma symptoms with an effect generally larger than previous studies have shown. A key benefit of using principal stratification in environmental intervention studies is that it allows investigators to estimate causal effects of the intervention for sub-groups defined by changes in the indoor air pollution concentration. Copyright © 2014 John Wiley & Sons, Ltd.

Environmental Monitoring of Microbe Metabolic Transformation

NASA Technical Reports Server (NTRS)

Bebout, Brad (Inventor); Fleming, Erich (Inventor); Piccini, Matthew (Inventor); Beasley, Christopher (Inventor); Bebout, Leslie (Inventor)

2013-01-01

Mobile system and method for monitoring environmental parameters involved in growth or metabolic transformation of algae in a liquid. Each of one or more mobile apparati, suspended or partly or wholly submerged in the liquid, includes at least first and second environmental sensors that sense and transmit distinct first and second environmental, growth or transformation parameter values, such as liquid temperature, temperature of gas adjacent to and above the exposed surface, liquid pH, liquid salinity, liquid turbidity, O.sub.2 dissolved in the liquid, CO.sub.2 contained in the liquid, oxidization and reduction potential of the liquid, nutrient concentrations in the liquid, nitrate concentration in the liquid, ammonium concentration in the liquid, bicarbonate concentration in the liquid, phosphate concentration in the liquid, light intensity at the liquid surface, electrical conductivity of the liquid, and a parameter.alpha.(alga) associated with growth stage of the alga, using PAM fluorometry or other suitable parameter measurements.

Effects of the amphibian chytrid fungus and four insecticides on Pacific treefrogs (Pseudacris regilla)

USGS Publications Warehouse

Kleinhez, Peter; Boone, Michelle D.; Fellers, Gary

2012-01-01

Chemical contamination may influence host-pathogen interactions, which has implications for amphibian population declines. We examined the effects of four insecticides alone or as a mixture on development and metamorphosis of Pacific Treefrogs (Pseudacris regilla) in the presence or absence of the amphibian chytrid fungus (Batrachochytrium dendrobatidis [Bd]). Bd exposure had a negative impact on tadpole activity, survival to metamorphosis, time to metamorphosis, and time of tail absorption (with a marginally negative effect on mass at metamorphosis); however, no individuals tested positive for Bd at metamorphosis. The presence of sublethal concentrations of insecticides alone or in a mixture did not impact Pacific Treefrog activity as tadpoles, survival to metamorphosis, or time and size to metamorphosis. Insecticide exposure did not influence the effect of Bd exposure. Our study did not support our prediction that effects of Bd would be greater in the presence of expected environmental concentrations of insecticide(s), but it did show that Bd had negative effects on responses at metamorphosis that could reduce the quality of juveniles recruited into the population.

Intertidal nematode communities in the Mekong estuaries of Vietnam and their potential for biomonitoring.

PubMed

Quang, Ngo Xuan; Chau, Nguyen Ngoc; Smol, Nic; Prozorova, Larisa; Vanreusel, Ann

2016-02-01

Nematode communities in eight Mekong estuaries were investigated during the dry season. The aim of the study was to identify the structure and the diversity of the communities in relation to the main environmental characteristics. In each estuary, three to four intertidal sampling stations were identified at regular distances from the mouth to up to 45 km land inward. The nematode communities showed a strong correlation with sediment composition and to a lesser degree with chlorophyll a concentrations. Multivariate analysis resulted in the identification of four types of communities. We identified two types of Desmodora communities in the sandy mouth stations and two types of Parodontophora communities in the silty sand stations. One of the silt associated communities showed a preference for higher chlorophyll a concentrations, resulting in higher densities and higher diversity, mainly of monhysterid species. Because of the strong association between community structure and sediment composition, nematodes are a meaningful tool for monitoring changes in their environment. In case their community deviates from what is expected based on sediment, it may serve as an early warning for disturbance.

Human health risk of polycyclic aromatic hydrocarbons from consumption of blood cockle and exposure to contaminated sediments and water along the Klang Strait, Malaysia.

PubMed

Tavakoly Sany, Seyedeh Belin; Hashim, Rosli; Rezayi, Majid; Salleh, Aishah; Rahman, Mohammad Azizur; Safari, Omid; Sasekumar, A

2014-07-15

The concentration of carcinogenic poly aromatic hydrocarbons (c-PAHs) present in water and sediment of Klang Strait as well as in the edible tissue of blood cockle (Anadara granosa) was investigated. The human health risk of c-PAHs was assessed in accordance with the standards of the United States Environmental Protection Agency (US EPA). The cancer risks of c-PAHs to human are expected to occur through the consumption of blood cockles or via gastrointestinal exposure to polluted sediments and water in Kalng Strait. The non-carcinogenic risks that are associated with multiple pathways based on ingestion rate and contact rates with water were higher than the US EPA safe level at almost all stations, but the non-carcinogenic risks for eating blood cockle was below the level of US EPA concern. A high correlation between concentrations of c-PAHs in different matrices showed that the bioaccumulation of c-PAHs by blood cockles could be regarded as a potential health hazard for the consumers. Copyright © 2014 Elsevier Ltd. All rights reserved.

Geochemical partitioning of lead in biogenic carbonate sediments in a coral reef depositional environment.

PubMed

Horta-Puga, Guillermo

2017-03-15

The fate of trace elements in reef depositional environments has not been extensively investigated. The aim of this study was to determine the partitioning of Pb in sediments of the Veracruz Reef System, and its relation to local environmental sources. Lead was determined in four geochemical fractions: exchangeable (3.8±0.4μgg -1 ), carbonate (57.0±13.6μgg -1 ), organic matter (2.0±0.9μgg -1 ), and mineral (17.5±5.4μgg -1 ). For the mineral fraction, lead concentrations were higher in those reefs influenced by river discharge or by long-distance transport of terrigenous sediments. The bioavailable concentration of lead (range: 21.9-85.6μgg -1 ) indicates that the Veracruz Reef System is a moderately polluted area. As expected, the carbonate fraction contained the highest proportion of Pb (70%), and because the reef framework is largely made up of by biogenic carbonate sediments, hence, it is therefore the most important repository of Pb in coral reef depositional environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preparing to understand and use science in the real world: interdisciplinary study concentrations at the Technical University of Darmstadt.

PubMed

Liebert, Wolfgang J

2013-12-01

In order to raise awareness of the ambiguous nature of scientific-technological progress, and of the challenging problems it raises, problems which are not easily addressed by courses in a single discipline and cannot be projected onto disciplinary curricula, Technical University of Darmstadt has established three interdisciplinary study concentrations: "Technology and International Development", "Environmental Sciences", and "Sustainable Shaping of Technology and Science". These three programmes seek to overcome the limitations of strictly disciplinary research and teaching by developing an integrated, problem-oriented approach. For example, one course considers fundamental nuclear dilemmas and uses role-playing techniques to address a controversy in the area of nuclear security. At the same time, incorporating interdisciplinary teaching into a university that is organized around mono- or multi-disciplinary faculties also poses a number of challenges. Recognition in disciplinary curricula, and appropriate organizational support and funding are examples of those challenges. It is expected that science and engineering students, empowered by such interdisciplinary study programmes, will be better prepared to act responsibly with regard to scientific and technological challenges.

An environmental chamber for investigating the evaporation of volatile chemicals.

PubMed

Dillon, H K; Rumph, P F

1998-03-01

An inexpensive test chamber has been constructed that provides an environment appropriate for testing the effects of temperature and chemical interactions on gaseous emissions from test solutions. Temperature, relative humidity, and ventilation rate can be controlled and a well-mixed atmosphere can be maintained. The system is relatively simple and relies on heated tap water or ice to adjust the temperature. Temperatures ranging from 9 to 21 degrees C have been maintained. At an average temperature of 15.1 degrees C, temperatures at any location within the chamber vary by no more than 0.5 degree C, and the temperature of the test solution within the chamber varies by no more than 0.1 degree C. The temperatures within the chamber are stable enough to generate precise steady-state concentrations. The wind velocities within the chamber are reproducible from run to run. Consequently, the effect of velocity on the rate of evaporation of a test chemical is expected to be uniform from run to run. Steady-state concentrations can be attained in less than 1 hour at an air exchange rate of about 5 per hour.

Fecal sterols, seasonal variability, and probable sources along the ring of cenotes, Yucatan, Mexico

NASA Astrophysics Data System (ADS)

Arcega-Cabrera, F.; Velázquez-Tavera, N.; Fargher, L.; Derrien, M.; Noreña-Barroso, E.

2014-11-01

Rapid development in Yucatan has had a dramatic impact on the environment, especially the water supply. Groundwater is the only source of water in Yucatan, since surface water is virtually absent due to the karstic nature of the soil. The ring of cenotes (RC) is a geological feature which functions as a source of water and as nodes in the underground river system that canalizes water towards the coast. Numerous productive and domestic activities take place around the RC in the absence of wastewater treatment or sewage systems. Consequently, a number of researchers have hypothesized that pollutants could migrate from the land surface to the underlying aquifer and, eventually, to the coast. Therefore, the present study investigates the relationship among sources of fecal sterols and their levels in cenotes, using the expected levels of fecal sterols obtained by a spatial analysis of the sources and a Pollution Source Index. Accordingly, expected levels are compared with the detected levels of fecal sterols in 5 areas around the RC. Regarding levels, observed during a sampling campaign carried out along the RC during September 2011 (rainy season) and May 2012 (dry season), varied from low to high concentrations of sterols (0.5-2396.42 μg g- 1) and fecal sterols (0.3-1690.18 μg g- 1). These concentrations showed no relationship between neighboring cenotes, where similar fecal sterol concentrations or gradients were expected. When comparing expected fecal sterols levels with the detected ones, only two of the five analyzed areas concur, suggesting that no clear relationship exists among sources and fecal sterols levels at the regional scale. Multivariate analysis showed that fecal sterols were associated with sterols and fine grain particulates during the rainy season, which suggests co-transport. During the dry season, fecal sterols associated with fine grain particulate and organic matter, which indicates a change to a deposition phenomenon. These findings indicate that defining a relationship among sources and fecal sterols levels is highly difficult and this could be the result of the absorption or migration through an intricate conduit, crack, or fracture karst system. Nevertheless, the “source-levels approach”, used in this study, was consistent for the northeast edge and the middle western part of the RC. New and more extensive research should be done to assess the environmental fate of fecal sterols, especially considering the intricate karstic system and its compound retention capacity.

Fecal sterols, seasonal variability, and probable sources along the ring of cenotes, Yucatan, Mexico.

PubMed

Arcega-Cabrera, F; Velázquez-Tavera, N; Fargher, L; Derrien, M; Noreña-Barroso, E

2014-11-01

Rapid development in Yucatan has had a dramatic impact on the environment, especially the water supply. Groundwater is the only source of water in Yucatan, since surface water is virtually absent due to the karstic nature of the soil. The ring of cenotes (RC) is a geological feature which functions as a source of water and as nodes in the underground river system that canalizes water towards the coast. Numerous productive and domestic activities take place around the RC in the absence of wastewater treatment or sewage systems. Consequently, a number of researchers have hypothesized that pollutants could migrate from the land surface to the underlying aquifer and, eventually, to the coast. Therefore, the present study investigates the relationship among sources of fecal sterols and their levels in cenotes, using the expected levels of fecal sterols obtained by a spatial analysis of the sources and a Pollution Source Index. Accordingly, expected levels are compared with the detected levels of fecal sterols in 5 areas around the RC. Regarding levels, observed during a sampling campaign carried out along the RC during September 2011 (rainy season) and May 2012 (dry season), varied from low to high concentrations of sterols (0.5-2396.42 μg g(-1)) and fecal sterols (0.3-1690.18 μg g(-1)). These concentrations showed no relationship between neighboring cenotes, where similar fecal sterol concentrations or gradients were expected. When comparing expected fecal sterols levels with the detected ones, only two of the five analyzed areas concur, suggesting that no clear relationship exists among sources and fecal sterols levels at the regional scale. Multivariate analysis showed that fecal sterols were associated with sterols and fine grain particulates during the rainy season, which suggests co-transport. During the dry season, fecal sterols associated with fine grain particulate and organic matter, which indicates a change to a deposition phenomenon. These findings indicate that defining a relationship among sources and fecal sterols levels is highly difficult and this could be the result of the absorption or migration through an intricate conduit, crack, or fracture karst system. Nevertheless, the "source-levels approach", used in this study, was consistent for the northeast edge and the middle western part of the RC. New and more extensive research should be done to assess the environmental fate of fecal sterols, especially considering the intricate karstic system and its compound retention capacity. Copyright © 2014 Elsevier B.V. All rights reserved.

Acquisition of Operational Environmental Literacy in Social Studies Course

ERIC Educational Resources Information Center

Fidan, Nuray Kurtdede; Ay, Tugba Selanik

2016-01-01

Environmental literacy can be defined as having necessary perceptions and competency of health and environmental systems and as being active in developing necessary acts about them. Individuals are expected to use their knowledge and concepts in daily life. The aim of this study is to determine students' views about operational environmental…

Environmental Globalization, Organizational Form, and Expected Benefits from Protected Areas in Central America

ERIC Educational Resources Information Center

Pfeffer, Max J.; Schelhas, John W.; Meola, Catherine

2006-01-01

Environmental globalization has led to the implementation of conservation efforts like the creation of protected areas that often promote the interests of core countries in poorer regions. The creation of protected areas in poor areas frequently creates tensions between human needs like food and shelter and environmental conservation. Support for…

A METHOD TO REMOVE ENVIRONMENTAL INHIBITORS PRIOR TO THE DETECTION OF WATERBORNE ENTERIC VIRUSES BY REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION

EPA Science Inventory

A method was developed to remove environmental inhibitors from sample concentrates prior to detection of human enteric viruses using the reverse transcription-polymerase chain reaction (RT-PCR).Environmental inhibitors, concentrated along with viruses during water sample processi...

Environmental Impact Statement Addressing Campus Development at Fort George Meade, Maryland

DTIC Science & Technology

2010-09-01

II, and III) Hazardous Materials and Wastes No impacts on hazardous materials and wastes would be expected. Short- and long-term, negligible...adverse impacts would be expected from generation of hazardous materials and petroleum products and wastes during construction and operational...activities. No impacts on asbestos-containing materials , radon, lead-based paint, pesticides, or polychlorinated biphenyls would be expected. Short

In vitro kinetics of hepatic glutathione s-transferase conjugation in largemouth bass and brown bullheads

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gallagher, E.P.; Sheehy, K.M.; Lame, M.W.

2000-02-01

The kinetics of glutathione 5-transferase (GST) catalysis were investigated in largemouth bass (Micropterus salmoides) and brown bullheads (Amerius nebulosus), two freshwater fish species found in a variety of polluted waterways in the eastern US. The initial rates of hepatic GST activity toward four GST substrates, including 1-chloro-2,4-dinitrobenzene, ethacrynic acid, {Delta}5-androstene-17-dione, and nitrobutyl chloride, were significantly higher in brown bullheads than in largemouth bass. Hepatic GST activity toward 1,2-dichloro-4-nitrobenzene, a {mu}-class GST substrate in rodents, was not detectable in either species. Liver cytosolic GSTs were more efficient in bullheads than in bass at catalyzing 1-chloro-2,4-dinitrobenzene-reduced glutathione (CDNB-GSH) conjugation over a broadmore » range of electrophile (CDNB) concentrations, including those representative of environmental exposure. In contrast, largemouth bass maintained higher ambient concentrations of GSH, the nucleophilic cofactor for GST-mediated conjugation, than brown bullheads. Biphasic kinetics for GST-CDNB conjugation under conditions of variable GSH concentration were apparent in Eadie-Hofstee plots of the kinetic data, suggesting the presence of at least two hepatic GST isozymes with markedly different K{sub m} values for GSH in both species. The GST-CDNB reaction rate data obtained under conditions of variable GSH were well fitted (R{sup 2} = 0.999) by the two-enzyme Michaelis-Menten equation. In addition, Western blotting experiments confirmed the presence of two different hepatic GST-like proteins in both largemouth bass and brown bullhead liver. Collectively, these findings indicate that largemouth bass and brown bullhead GSTs catalyze the conjugation of structurally diverse, class-specific GST substrates, and that brown bullheads exhibit higher initial rates of GST activity than largemouth bass. The relatively higher rates of in vitro liver GST activity at the low substrate concentrations relevant to environmental exposure is expected to protect brown bullheads from the toxic effects of sediment-associated electrophilic chemicals. The somewhat lower rates of GST activity in largemouth bass liver compared with brown bullhead liver, however, may be offset by maintenance of higher ambient hepatic GSH concentrations in largemouth bass.« less

Estimating true human and animal host source contribution in quantitative microbial source tracking using the Monte Carlo method.

PubMed

Wang, Dan; Silkie, Sarah S; Nelson, Kara L; Wuertz, Stefan

2010-09-01

Cultivation- and library-independent, quantitative PCR-based methods have become the method of choice in microbial source tracking. However, these qPCR assays are not 100% specific and sensitive for the target sequence in their respective hosts' genome. The factors that can lead to false positive and false negative information in qPCR results are well defined. It is highly desirable to have a way of removing such false information to estimate the true concentration of host-specific genetic markers and help guide the interpretation of environmental monitoring studies. Here we propose a statistical model based on the Law of Total Probability to predict the true concentration of these markers. The distributions of the probabilities of obtaining false information are estimated from representative fecal samples of known origin. Measurement error is derived from the sample precision error of replicated qPCR reactions. Then, the Monte Carlo method is applied to sample from these distributions of probabilities and measurement error. The set of equations given by the Law of Total Probability allows one to calculate the distribution of true concentrations, from which their expected value, confidence interval and other statistical characteristics can be easily evaluated. The output distributions of predicted true concentrations can then be used as input to watershed-wide total maximum daily load determinations, quantitative microbial risk assessment and other environmental models. This model was validated by both statistical simulations and real world samples. It was able to correct the intrinsic false information associated with qPCR assays and output the distribution of true concentrations of Bacteroidales for each animal host group. Model performance was strongly affected by the precision error. It could perform reliably and precisely when the standard deviation of the precision error was small (≤ 0.1). Further improvement on the precision of sample processing and qPCR reaction would greatly improve the performance of the model. This methodology, built upon Bacteroidales assays, is readily transferable to any other microbial source indicator where a universal assay for fecal sources of that indicator exists. Copyright © 2010 Elsevier Ltd. All rights reserved.

Environmental control of U concentration and 234U/238U in speleothems at subannual resolution

NASA Astrophysics Data System (ADS)

Hu, C.; Henderson, G. M.

2003-12-01

Trace element and isotope variability in speleothems encodes a range of information about the past environment, although its interpretation is often problematic. U concentration and isotopes have frequently been analysed in speleothems in order to provide chronology, but their use as environmental proxies in their own right has not been comprehensively investigated. In this study, we have investigated the environmental controls of U in a stalagmite from the Central Yangtze Valley in China. This stalagmite grew rapidly throughout the Holocone and contains visible annual layers about 300microns thick. Analysis of a portion of the stalagmite corresponding to the 1970s by electron probe, LA-ICP-MS, and by physical subsampling indicate clear annual cycles in Sr/Ca, Mg/Ca, and Ba/Ca. The reasonably open cave structure and the correlation of Sr/Ca with Mg/Ca suggest that temperature exerts considerable control over these trace element variations. U/Ca also varies seasonally by up to 42 % and shows a clear anti-correlation with Mg/Ca (correlation coefficient -0.64). Based on the inverse relationship between U/Ca and temperature exhibited in other carbonates (e.g. corals) the speleothem U/Ca is suggested to be controlled primarily by temperature and may provide a paleo cave thermometer with less rainfall influence than Mg/Ca. Ongoing monitoring of the cave temperature and humidity will assess the robustness of this conclusion and the sensitivity of speleothem U/Ca to temperature. (234U/238U) in this stalagmite range from 1.733 to 1.872 during the Holocene. The U concentration is high enough (typically 0.48 ppm) and growth rate fast enough, that (234U/238U) can also be measured at a subannual resolution. The expected alpha-recoil control of excess 234U supply suggests that these measurements may provide a measure of the transit time of recharge waters to the stalagmite during the seasonal cycle. Such a proxy would enable deconvolution of temperature and recharge-rate control in trace element records from speleothems.

EPA Use of Ecological Nonmarket Valuation

EPA Science Inventory

This essay was motivated by a workshop at which numerous investigators presented advancements in nonmarket valuation . Much of the research, and the workshop itself were US Environmental Protection Agency (EPA) funded, and indeed the typical expected application was environmental...

Is coccolithophore distribution in the Mediterranean Sea related to seawater carbonate chemistry?

NASA Astrophysics Data System (ADS)

Oviedo, A. M.; Ziveri, P.; Álvarez, M.; Tanhua, T.

2014-02-01

The Mediterranean Sea is considered a "hot-spot" for climate change, being characterized by oligotrophic to ultra-oligotrophic waters and rapidly changing carbonate chemistry. Coccolithophores are considered a dominant phytoplankton group in these waters. As a marine calcifying organism they are expected to respond to the ongoing changes in seawater CO2 systems parameters. However, very few studies have covered the entire Mediterranean physiochemical gradients from the Strait of Gibraltar to the Eastern Mediterranean Levantine Basin. We provide here an updated state of knowledge of the coccolithophore distribution in the Mediterranean Sea and relate this to a broad set of in situ measured environmental variables. Samples were taken during the Meteor (M84/3) oceanographic cruise in April 2011, between 0-100 m water depth from 28 stations. Total diatom, dinoflagellate and silicoflagellate cell concentrations are also presented. Our results highlight the importance of seawater carbonate chemistry, especially CO32-, in unraveling the distribution of heterococcolithophores, the most abundant coccolithophore life phase. Holo- and hetero-coccolithophores respond differently to environmental factors. For instance, changes in heterococcolithophore assemblages were best linked to the combination of [CO32-], pH, and salinity (ρ = 0.57) although salinity might be not functionally related to coccolithophore assemblage distribution. Holococcolithophores, on the other hand, were preferentially distributed and showed higher species diversity in oligotrophic areas (Best fit, ρ = 0.32 for nutrients), thriving in nutrient depleted waters. Clustering of heterococcolithophores revealed three groups of species sharing more than 65% similarities. These clusters could be assigned to the eastern and western basins, and deeper layers (below 50 m), respectively. In addition, the species Gephyrocapsa oceanica, G. muellerae and Emiliania huxleyi morphotype B/C are spatially distributed together and trace the influx of Atlantic waters into the Mediterranean Sea. The results of the present work emphasize the importance of considering holo- and hetero-coccolithophores separately when analyzing changes in species assemblages and diversity. Our findings clearly show that coccolithophores are a dominant phytoplankton group in the entire Mediterranean Sea; they have life stages that are expected to respond differently to the variability in seawater carbonate chemistry and nutrient concentrations.

Is coccolithophore distribution in the Mediterranean Sea related to seawater carbonate chemistry?

NASA Astrophysics Data System (ADS)

Oviedo, A.; Ziveri, P.; Álvarez, M.; Tanhua, T.

2015-01-01

The Mediterranean Sea is considered a "hot spot" for climate change, being characterized by oligotrophic to ultra-oligotrophic waters and rapidly increasing seasurface temperature and changing carbonate chemistry. Coccolithophores are considered a dominant phytoplankton group in these waters. As marine calcifying organisms they are expected to respond to the ongoing changes in seawater carbonate chemistry. We provide here a description of the springtime coccolithophore distribution in the Mediterranean Sea and relate this to a broad set of in situ-measured environmental variables. Samples were taken during the R/V Meteor (M84/3) oceanographic cruise in April 2011, between 0 and 100 m water depth from 28 stations. Total diatom and silicoflagellate cell concentrations are also presented. Our results highlight the importance of seawater carbonate chemistry, especially [CO32-] but also [PO43-] in unraveling the distribution of heterococcolithophores, the most abundant coccolithophore life phase. Holo- and heterococcolithophores respond differently to environmental factors. For instance, changes in heterococcolithophore assemblages were best linked to the combination of [CO32-], pH, and salinity (ρ = 0.57), although salinity might be not functionally related to coccolithophore assemblage distribution. Holococcolithophores, on the other hand, showed higher abundances and species diversity in oligotrophic areas (best fit, ρ = 0.32 for nutrients), thriving in nutrient-depleted waters. Clustering of heterococcolithophores revealed three groups of species sharing more than 65% similarities. These clusters could be assigned to the eastern and western basins and deeper layers (below 50 m), respectively. In addition, the species Gephyrocapsa oceanica, G. muellerae, and Emiliania huxleyi morphotype B/C are spatially distributed together and trace the influx of Atlantic waters into the Mediterranean Sea. The results of the present work emphasize the importance of considering holo- and heterococcolithophores separately when analyzing changes in species assemblages and diversity. Our findings suggest that coccolithophores are a main phytoplankton group in the entire Mediterranean Sea and can dominate over siliceous phytoplankton. They have life stages that are expected to respond differently to the variability in seawater carbonate chemistry and nutrient concentrations.

Environmental change makes robust ecological networks fragile

USGS Publications Warehouse

Strona, Giovanni; Lafferty, Kevin D.

2016-01-01

Complex ecological networks appear robust to primary extinctions, possibly due to consumers’ tendency to specialize on dependable (available and persistent) resources. However, modifications to the conditions under which the network has evolved might alter resource dependability. Here, we ask whether adaptation to historical conditions can increase community robustness, and whether such robustness can protect communities from collapse when conditions change. Using artificial life simulations, we first evolved digital consumer-resource networks that we subsequently subjected to rapid environmental change. We then investigated how empirical host–parasite networks would respond to historical, random and expected extinction sequences. In both the cases, networks were far more robust to historical conditions than new ones, suggesting that new environmental challenges, as expected under global change, might collapse otherwise robust natural ecosystems.

Mercury speciation in sediments at a municipal sewage sludge marine disposal site.

PubMed

Shoham-Frider, E; Shelef, G; Kress, N

2007-12-01

Mercury speciation was performed in excess activated sewage sludge (ASS) and in marine sediments collected at the AAS disposal site off the Mediterranean coast of Israel in order to characterize the spatial and vertical distribution of different mercury species and assess their environmental impact. Total Hg (HgT) concentrations ranged between 0.19 and 1003ng/g at the polluted stations and 5.7 and 72.8ng/g at the background station, while the average concentration in ASS was 1181+/-273ng/g. Only at the polluted stations did HgT concentrations decrease exponentially with sediment depth, reaching background values at 16-20cm, the vertical distribution resulting from mixing of natural sediment with ASS solids and bioturbation by large populations of polycheates. Average Methyl Hg (MeHg) concentration in ASS was 39.7+/-7.1ng/g, ca. 3% of the HgT concentration, while the background concentrations ranged between 0.1 and 0.61ng/g. MeHg concentrations in surficial polluted sediments were 0.7-5.9ng/g (ca. 0.5% of the HgT) and decreased vertically, similar to HgT. A positive correlation between MeHg and Hg only at the polluted stations, higher MeHg concentrations at the surface of the sediment and not below the redoxline, and no seasonality in the concentrations suggest that the MeHg originated from the ASS and not from in situ methylation. By doing selective extractions, we found that ca. 80% of the total Hg in ASS and polluted sediments was strongly bound to amorphous organo-sulfur and to inorganic sulfide species that are not bioavailable. The fractions with potential bioaccessible Hg had maximal concentrations in the range in which biotic effects should be expected. Therefore, although no bioaccumulation was found in the biota in the area, the concentration in the polluted sediments are not negligible and should be carefully monitored.

Fluorescence-based proxies for lignin in freshwater dissolved organic matter

USGS Publications Warehouse

Hernes, Peter J.; Bergamaschi, Brian A.; Eckard, Robert S.; Spencer, Robert G.M.

2009-01-01

Lignin phenols have proven to be powerful biomarkers in environmental studies; however, the complexity of lignin analysis limits the number of samples and thus spatial and temporal resolution in any given study. In contrast, spectrophotometric characterization of dissolved organic matter (DOM) is rapid, noninvasive, relatively inexpensive, requires small sample volumes, and can even be measured in situ to capture fine-scale temporal and spatial detail of DOM cycling. Here we present a series of cross-validated Partial Least Squares models that use fluorescence properties of DOM to explain up to 91% of lignin compositional and concentration variability in samples collected seasonally over 2 years in the Sacramento River/San Joaquin River Delta in California, United States. These models were subsequently used to predict lignin composition and concentration from fluorescence measurements collected during a diurnal study in the San Joaquin River. While modeled lignin composition remained largely unchanged over the diurnal cycle, changes in modeled lignin concentrations were much greater than expected and indicate that the sensitivity of fluorescence-based proxies for lignin may prove invaluable as a tool for selecting the most informative samples for detailed lignin characterization. With adequate calibration, similar models could be used to significantly expand our ability to study sources and processing of DOM in complex surface water systems.

LC-MS based metabolomics and chemometrics study of the toxic effects of copper on Saccharomyces cerevisiae.

PubMed

Farrés, Mireia; Piña, Benjamí; Tauler, Romà

2016-08-01

Copper containing fungicides are used to protect vineyards from fungal infections. Higher residues of copper in grapes at toxic concentrations are potentially toxic and affect the microorganisms living in vineyards, such as Saccharomyces cerevisiae. In this study, the response of the metabolic profiles of S. cerevisiae at different concentrations of copper sulphate (control, 1 mM, 3 mM and 6 mM) was analysed by liquid chromatography coupled to mass spectrometry (LC-MS) and multivariate curve resolution-alternating least squares (MCR-ALS) using an untargeted metabolomics approach. Peak areas of the MCR-ALS resolved elution profiles in control and in Cu(ii)-treated samples were compared using partial least squares regression (PLSR) and PLS-discriminant analysis (PLS-DA), and the intracellular metabolites best contributing to sample discrimination were selected and identified. Fourteen metabolites showed significant concentration changes upon Cu(ii) exposure, following a dose-response effect. The observed changes were consistent with the expected effects of Cu(ii) toxicity, including oxidative stress and DNA damage. This research confirmed that LC-MS based metabolomics coupled to chemometric methods are a powerful approach for discerning metabolomics changes in S. cerevisiae and for elucidating modes of toxicity of environmental stressors, including heavy metals like Cu(ii).

Thyroid function and perchlorate in drinking water: an evaluation among California newborns, 1998.

PubMed

Buffler, Patricia A; Kelsh, Michael A; Lau, Edmund C; Edinboro, Charlotte H; Barnard, Julie C; Rutherford, George W; Daaboul, Jorge J; Palmer, Lynn; Lorey, Fred W

2006-05-01

Perchlorate (ClO4-) has been detected in groundwater sources in numerous communities in California and other parts of the United States, raising concerns about potential impacts on health. For California communities where ClO4- was tested in 1997 and 1998, we evaluated the prevalence of primary congenital hypothyroidism (PCH) and high thyroid-stimulating hormone (TSH) levels among the 342,257 California newborns screened in 1998. We compared thyroid function results among newborns from 24 communities with average ClO4- concentrations in drinking water>5 microg/L (n=50,326) to newborns from 287 communities with average concentrations5 microg/L were observed, with 20.4 expected [adjusted prevalence odds ratio (POR)=0.71; 95% confidence interval (CI), 0.40-1.19]. Although only 36% of all California newborns were screened before 24 hr of age in 1998, nearly 80% of newborns with high TSH were screened before 24 hr of age. Because of the physiologic postnatal surge of TSH, the results for newborns screened before 24 hr were uninformative for assessing an environmental impact. For newborns screened>or=24 hr, the adjusted POR for high TSH was 0.73 (95% CI, 0.40-1.23). All adjusted odds ratios (ORs) were controlled for sex, ethnicity, birth weight, and multiple birth status. Using an assessment of ClO4- in drinking water based on available data, we did not observe an association between estimated average ClO4- concentrations>5 microg/L in drinking water supplies and the prevalence of clinically diagnosed PCH or high TSH concentrations.

Mercury contamination in fish in midcontinent great rivers of the United States: Importance of species traits and environmental factors

EPA Science Inventory

We measured mercury (Hg) concentrations in whole fish from the Upper Mississippi, Missouri and Ohio Rivers to characterize the extent and magnitude of Hg contamination and to identify environmental factors influencing Hg concentrations. Concentrations were generally lower than th...

The Importance of Pro-Environmental Behavior in Adolescent

NASA Astrophysics Data System (ADS)

Palupi, Tyas; Sawitri, Dian R.

2018-02-01

Studies regarding pro-environmental behavior in adolescents are lacking. This study aimed to examine the importance of pro-environmental behavior in adolescents (high school and university students) by conducting literature review from previous studies on pro environmental behavior. Pro-environmental behavior is the behavior of individuals that contributes towards environmental preservation. Based on previous studies, measurement of pro-environmental behavior were investigated on several theories, namely theory of planned behavior (TPB) and value, belief, norms (VBN) by using aspects of pro environmental behavior. Young people with critical thinking, and good environmental education, are expected to behave more environmentally friendly for creating a sustainable future.

Biotech crops: imperative for achieving the millenium development goals and sustainability of agriculture in the climate change era.

PubMed

Husaini, Amjad M; Tuteja, Narendra

2013-01-01

Biotechnological intervention in the development of crops has opened new vistas in agriculture. Central to the accomplishment of the Millennium Development Goals (MDGs), biotech-agriculture is essential in meeting these targets. Biotech crops have already made modest contributions toward ensuring food and nutrition security by reducing losses and increasing productivity, with less pesticide input. These crops could help address some of the major challenges in agriculture-based economies created by climate change. Projections of global climate change expect the concentration of greenhouse gases to increase, aridization of the environment to increase, temperature fluctuations to occur sharply and frequently, and spatial and temporal distribution of rainfall to be disturbed-all of which will increase abiotic stress-related challenges to crops. Countering these challenges and to meet the food requirement of the ever-increasing world population (expected to reach 9 billion by 2030) we need to (1) develop and use biotech crops for mitigating adverse climatic changes; (2) develop biotech crops resilient to adverse environmental conditions; and (3) address the issues/non-issues raised by NGO's and educate the masses about the benefits of biotech crops.

The search for signs of recovery of the ozone layer.

PubMed

Weatherhead, Elizabeth C; Andersen, Signe Bech

2006-05-04

Evidence of mid-latitude ozone depletion and proof that the Antarctic ozone hole was caused by humans spurred policy makers from the late 1980s onwards to ratify the Montreal Protocol and subsequent treaties, legislating for reduced production of ozone-depleting substances. The case of anthropogenic ozone loss has often been cited since as a success story of international agreements in the regulation of environmental pollution. Although recent data suggest that total column ozone abundances have at least not decreased over the past eight years for most of the world, it is still uncertain whether this improvement is actually attributable to the observed decline in the amount of ozone-depleting substances in the Earth's atmosphere. The high natural variability in ozone abundances, due in part to the solar cycle as well as changes in transport and temperature, could override the relatively small changes expected from the recent decrease in ozone-depleting substances. Whatever the benefits of the Montreal agreement, recovery of ozone is likely to occur in a different atmospheric environment, with changes expected in atmospheric transport, temperature and important trace gases. It is therefore unlikely that ozone will stabilize at levels observed before 1980, when a decline in ozone concentrations was first observed.

Influence of indoor environmental factors on mass transfer parameters and concentrations of semi-volatile organic compounds.

PubMed

Wei, Wenjuan; Mandin, Corinne; Ramalho, Olivier

2018-03-01

Semi-volatile organic compounds (SVOCs) in indoor environments can partition among the gas phase, airborne particles, settled dust, and available surfaces. The mass transfer parameters of SVOCs, such as the mass transfer coefficient and the partition coefficient, are influenced by indoor environmental factors. Subsequently, indoor SVOC concentrations and thus occupant exposure can vary depending on environmental factors. In this review, the influence of six environmental factors, i.e., indoor temperature, humidity, ventilation, airborne particle concentration, source loading factor, and reactive chemistry, on the mass transfer parameters and indoor concentrations of SVOCs was analyzed and tentatively quantified. The results show that all mass transfer parameters vary depending on environmental factors. These variations are mostly characterized by empirical equations, particularly for humidity. Theoretical calculations of these parameters based on mass transfer mechanisms are available only for the emission of SVOCs from source surfaces when airborne particles are not present. All mass transfer parameters depend on the temperature. Humidity influences the partition of SVOCs among different phases and is associated with phthalate hydrolysis. Ventilation has a combined effect with the airborne particle concentration on SVOC emission and their mass transfer among different phases. Indoor chemical reactions can produce or eliminate SVOCs slowly. To better model the dynamic SVOC concentration indoors, the present review suggests studying the combined effect of environmental factors in real indoor environments. Moreover, interactions between indoor environmental factors and human activities and their influence on SVOC mass transfer processes should be considered. Copyright © 2017 Elsevier Ltd. All rights reserved.

Adjustment of Pesticide Concentrations for Temporal Changes in Analytical Recovery, 1992-2006

USGS Publications Warehouse

Martin, Jeffrey D.; Stone, Wesley W.; Wydoski, Duane S.; Sandstrom, Mark W.

2009-01-01

Recovery is the proportion of a target analyte that is quantified by an analytical method and is a primary indicator of the analytical bias of a measurement. Recovery is measured by analysis of quality-control (QC) water samples that have known amounts of target analytes added ('spiked' QC samples). For pesticides, recovery is the measured amount of pesticide in the spiked QC sample expressed as percentage of the amount spiked, ideally 100 percent. Temporal changes in recovery have the potential to adversely affect time-trend analysis of pesticide concentrations by introducing trends in environmental concentrations that are caused by trends in performance of the analytical method rather than by trends in pesticide use or other environmental conditions. This report examines temporal changes in the recovery of 44 pesticides and 8 pesticide degradates (hereafter referred to as 'pesticides') that were selected for a national analysis of time trends in pesticide concentrations in streams. Water samples were analyzed for these pesticides from 1992 to 2006 by gas chromatography/mass spectrometry. Recovery was measured by analysis of pesticide-spiked QC water samples. Temporal changes in pesticide recovery were investigated by calculating robust, locally weighted scatterplot smooths (lowess smooths) for the time series of pesticide recoveries in 5,132 laboratory reagent spikes; 1,234 stream-water matrix spikes; and 863 groundwater matrix spikes. A 10-percent smoothing window was selected to show broad, 6- to 12-month time scale changes in recovery for most of the 52 pesticides. Temporal patterns in recovery were similar (in phase) for laboratory reagent spikes and for matrix spikes for most pesticides. In-phase temporal changes among spike types support the hypothesis that temporal change in method performance is the primary cause of temporal change in recovery. Although temporal patterns of recovery were in phase for most pesticides, recovery in matrix spikes was greater than recovery in reagent spikes for nearly every pesticide. Models of recovery based on matrix spikes are deemed more appropriate for adjusting concentrations of pesticides measured in groundwater and stream-water samples than models based on laboratory reagent spikes because (1) matrix spikes are expected to more closely match the matrix of environmental water samples than are reagent spikes and (2) method performance is often matrix dependent, as was shown by higher recovery in matrix spikes for most of the pesticides. Models of recovery, based on lowess smooths of matrix spikes, were developed separately for groundwater and stream-water samples. The models of recovery can be used to adjust concentrations of pesticides measured in groundwater or stream-water samples to 100 percent recovery to compensate for temporal changes in the performance (bias) of the analytical method.

Evolution of phenotypic plasticity and environmental tolerance of a labile quantitative character in a fluctuating environment.

PubMed

Lande, R

2014-05-01

Quantitative genetic models of evolution of phenotypic plasticity are used to derive environmental tolerance curves for a population in a changing environment, providing a theoretical foundation for integrating physiological and community ecology with evolutionary genetics of plasticity and norms of reaction. Plasticity is modelled for a labile quantitative character undergoing continuous reversible development and selection in a fluctuating environment. If there is no cost of plasticity, a labile character evolves expected plasticity equalling the slope of the optimal phenotype as a function of the environment. This contrasts with previous theory for plasticity influenced by the environment at a critical stage of early development determining a constant adult phenotype on which selection acts, for which the expected plasticity is reduced by the environmental predictability over the discrete time lag between development and selection. With a cost of plasticity in a labile character, the expected plasticity depends on the cost and on the environmental variance and predictability averaged over the continuous developmental time lag. Environmental tolerance curves derived from this model confirm traditional assumptions in physiological ecology and provide new insights. Tolerance curve width increases with larger environmental variance, but can only evolve within a limited range. The strength of the trade-off between tolerance curve height and width depends on the cost of plasticity. Asymmetric tolerance curves caused by male sterility at high temperature are illustrated. A simple condition is given for a large transient increase in plasticity and tolerance curve width following a sudden change in average environment. © 2014 The Author. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Evaluation of genotoxicity in workers exposed to low levels of formaldehyde in a furniture manufacturing facility.

PubMed

Peteffi, Giovana Piva; da Silva, Luciano Basso; Antunes, Marina Venzon; Wilhelm, Camila; Valandro, Eduarda Trevizani; Glaeser, Jéssica; Kaefer, Djeine; Linden, Rafael

2016-10-01

Formaldehyde (FA) is a chemical widely used in the furniture industry and has been classified as a potential human carcinogen. The purpose of this study was to evaluate the occupational exposure of workers to FA at a furniture manufacturing facility and the relationship between environmental concentrations of FA, formic acid concentration in urine, and DNA damage. The sample consisted of 46 workers exposed to FA and a control group of 45 individuals with no history of occupational exposure. Environmental concentrations of FA were determined by high-performance liquid chromatography. Urinary formic acid concentrations were determined by gas chromatography with flame ionization detector. DNA damage was evaluated by the micronucleus (MN) test performed in exfoliated buccal cells and comet assay with venous blood. The 8-h time-weighted average of FA environmental concentration ranged from 0.03 ppm to 0.09 ppm at the plant, and the control group was exposed to a mean concentration of 0.012 ppm. Workers exposed to higher environmental FA concentrations had urinary formic acid concentrations significantly different from those of controls (31.85 mg L(-1) vs. 19.35 mg L(-), p ≤ 0.01 Mann-Whitney test). Significant differences were found between control and exposed groups for the following parameters: damage frequency and damage index in the comet assay, frequency of binucleated cells in the MN test, and formic acid concentration in urine. The frequency of micronuclei, nuclear buds, and karyorrhexis did not differ between groups. There was a positive correlation between environmental concentrations of FA and damage frequency (Spearman's rank correlation coefficient [r s] = 0.24), damage index (r s = 0.21), binucleated cells (r s = 0.34), and urinary formic acid concentration (r s = 0.63). The results indicate that, although workers in the furniture manufacturing facility were exposed to low environmental levels of FA, this agent contributes to the observed increase in cytogenetic damage. In addition, urinary formic acid concentrations correlated strongly with occupational exposure to FA. © The Author(s) 2015.

Is expectancy reality? Associations between tension reduction beliefs and mood following alcohol consumption.

PubMed

Merrill, Jennifer E; Wardell, Jeffrey D; Read, Jennifer P

2009-12-01

The present study investigated whether tension reduction expectancies were uniquely associated with self-reported mood following in-lab alcohol administration, given that little research has addressed this association. We also tested whether level of experience with alcohol, which may influence the learning of expectancies, moderated expectancy-mood associations. Regularly drinking college students (N = 145) recruited through advertisements completed self-report measures of positive alcohol expectancies, alcohol involvement, demographics, and pre- and post-drinking mood, and then consumed alcohol ad libitum up to four drinks in the laboratory. Regression analyses controlling for pre-consumption mood, blood alcohol concentration, and all other positive expectancies showed tension reduction expectancies to be a marginally significant positive predictor of negative mood post-drinking. This association was significant only for those who achieved lower blood alcohol concentrations in lab and those who reported less involvement with alcohol (i.e., lower typical quantity, heavy episodic drinking frequency, and years of regular drinking). Findings suggest that associations between expectations for mood and actual post-drinking mood outcomes may operate differently for less versus more involved drinkers. Clinical implications pertain to early intervention, when expectancies may be less ingrained and perhaps more readily modified.

Ground level environmental protein concentrations in various ecuadorian environments: potential uses of aerosolized protein for ecological research

USGS Publications Warehouse

Staton, Sarah J.R.; Woodward, Andrea; Castillo, Josemar A.; Swing, Kelly; Hayes, Mark A.

2014-01-01

Large quantities of free protein in the environment and other bioaerosols are ubiquitous throughout terrestrial ground level environments and may be integrative indicators of ecosystem status. Samples of ground level bioaerosols were collected from various ecosystems throughout Ecuador, including pristine humid tropical forest (pristine), highly altered secondary humid tropical forest (highly altered), secondary transitional very humid forest (regrowth transitional), and suburban dry montane deforested (suburban deforested). The results explored the sensitivity of localized aerosol protein concentrations to spatial and temporal variations within ecosystems, and their value for assessing environmental change. Ecosystem specific variations in environmental protein concentrations were observed: pristine 0.32 ± 0.09 μg/m3, highly altered 0.07 ± 0.05 μg/m3, regrowth transitional 0.17 ± 0.06 μg/m3, and suburban deforested 0.09 ± 0.04 μg/m3. Additionally, comparisons of intra-environmental differences in seasonal/daily weather (dry season 0.08 ± 0.03 μg/m3 and wet season 0.10 ± 0.04 μg/m3), environmental fragmentation (buffered 0.19 ± 0.06 μg/m3 and edge 0.15 ± 0.06 μg/m3), and sampling height (ground level 0.32 ± 0.09 μg/m3 and 10 m 0.24 ± 0.04 μg/m3) demonstrated the sensitivity of protein concentrations to environmental conditions. Local protein concentrations in altered environments correlated well with satellite-based spectral indices describing vegetation productivity: normalized difference vegetation index (NDVI) (r2 = 0.801), net primary production (NPP) (r2 = 0.827), leaf area index (LAI) (r2 = 0.410). Moreover, protein concentrations distinguished the pristine site, which was not differentiated in spectral indices, potentially due to spectral saturation typical of highly vegetated environments. Bioaerosol concentrations represent an inexpensive method to increase understanding of environmental changes, especially in densely vegetated ecosystems with high canopies or in areas needing high spatial and temporal resolution. Further research to expand understanding of the applicability of bioaerosol concentrations for environmental monitoring is supported by this pilot study.

Fiscal Year 2018 National Environmental Information Exchange Network Grant Solicitation Notice

EPA Pesticide Factsheets

The Exchange Network Grant Program provides funding for projects that are in line with Exchange Network priorities. The primary outcome expected from EN assistance agreements is improved access to, and exchange of, high quality environmental data.

Major Matters: Relationship between Academic Major and University Students' Environmental Literacy and Citizenship as Reflected in Their Voting Decisions and Environmental Activism

ERIC Educational Resources Information Center

Goldman, Daphne; Ayalon, Ofira; Baum, Dorit; Haham, Shay

2015-01-01

Institutions of higher education (HE) are increasingly expected to rise to the challenge of preparing environmentally literate graduates, equipped to bring a sustainability perspective into their professional function. While considerable research has explored the relationship between HE and tendency for political participation in general, studies…

78 FR 46925 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Snapper-Grouper Fishery off the...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-02

... preparation of a draft environmental impact statement (EIS) to an EA for Regulatory Amendment 14. FOR FURTHER... of No Significant Impact (FONSI), the EA and FONSI will be the final environmental documents required by NEPA. If the EA reveals that significant environmental impacts may be reasonably expected to...

Measuring the attitudes and awareness of environmental education camp users

Treesearch

Roger E. McCay; David A. Gansner; John J. Padalino

1978-01-01

Questionnaires for evaluating what people expect from environmental camps and what they learn while there have been developed and applied at the Pocono Environmental Education Center, Dingman's Ferry, Penna. Nine questionnaires for various ages and types of users are presented. The results can be used by camp administrators and educators to evaluate their own...

Environmental globalization, organizational form, and expected benefits from protected areas in Central America

Treesearch

Max J. Pfeffer; John W. Schelhas; Catherine Meola

2006-01-01

Environmental globalization has led to the implementation of conservation efforts like the creation of protected areas that often promote the interests of core countries in poorer regions. The creation of protected areas in poor areas frequently creates tensions between human needs like - food and shelter and environmental conservation. Support for such conservation...

Lead from hunting activities and its potential environmental threat to wildlife in a protected wetland in Yucatan, Mexico.

PubMed

Arcega-Cabrera, Flor; Noreña-Barroso, Elsa; Oceguera-Vargas, Ismael

2014-02-01

This study provides insights into the status of lead in the protected wetland of El Palmar, located on the northwestern littoral of the Yucatan Peninsula. This reserve is ecologically and economically important because it provides feeding and breeding habitats for many species, as well as being an ecotourism destination (especially for bird watching). Although it is a protected area, duck species are heavily hunted within the reserve during the winter. As a result, animals feeding or living in sediments could be exposed to anthropogenic lead. Total lead and its geochemical fractionated forms were measured in sediment cores from six selected sites in "El Palmar" wetland, during pre- and post-hunting seasons, to approximate the potential environmental threat (especially for benthonic living/feeding organisms). Anthropogenic lead concentrations detected in soil cores ranged from below the minimum infaunal community effect level (30.24 μg g(-1)) during the pre-hunting season, to bordering the probable infaunal community effect level (112.18 μg g(-1)) during the post-hunting season, according to SquiiRTs NOAA guidelines. Yet, these results were lower than expected based on the intensity of hunting. Consequently, this article explores the possibility that the lower than expected lead concentration in sediments results from (1) degradation of shot and transformation to soluble or particulate forms; or (2) ingestion of lead shot by benthic and other lacustrine species living in the protected area. Geochemical fractionation of lead demonstrated that in the top 6 cm of the soil column at heavily active hunting sites (EP5 and EP6), lead was associated with the lithogenic fraction (average 45 percent) and with the organic fraction (average 20 percent). Bioavailable lead (sum of lead adsorbed to the carbonates, Fe/Mn oxyhydroxides and organic fractions) in sediments was lower than 50 percent for the heavily active hunting areas and higher for the rest of the sites. Multivariate analysis showed that the environmental chemistry, the physicochemical characteristics of the water, and the geochemical qualities of the sediments do not favor the release of lead into the water column. Thus, the direct consumption of lead shot by organisms feeding in sea grass or in the top 10 cm of sediment is perhaps the major process preventing lead from being deposited in sediments, and, as such, these species (e.g., flamingos and/or ducks) could be threatened by anthropogenic lead pollution. © 2013 Published by Elsevier Inc.

Association between worldwide dietary and lifestyle patterns with total cholesterol concentrations and DALYs for infectious and cardiovascular diseases: an ecological analysis.

PubMed

Oggioni, C; Cena, H; Wells, J C K; Lara, J; Celis-Morales, C; Siervo, M

2015-12-01

Global dietary and lifestyle trends are primary risk factors for communicable and non-communicable diseases. An ecological analysis was conducted to examine the association of global dietary and lifestyle patterns with total cholesterol concentrations. This study also investigated whether total cholesterol modified the association between dietary and lifestyle habits with disability-adjusted-life-years-lost (DALYs) for infectious and cardiovascular diseases (CVDs). Country-specific mean total cholesterol concentrations and DALYs for infectious and CVDs were obtained. Data were then matched to country-specific food and energy availability for consumption and information on obesity, physical inactivity, urbanization, gross domestic product (GDP), life expectancy and smoking. Stepwise multiple regression models were developed to identify significant predictors of total cholesterol concentrations and DALYs for infectious and CVDs. Life expectancy and egg and meat consumption were significantly associated with cholesterol concentrations. DALYs for infectious diseases were associated with smoking, life expectancy and per capita GDP. Smoking was the only predictor of DALYs for CVDs. The improvement of socio-demographic conditions and economic growth is likely to reduce the burden of communicable diseases in developing countries. A concurring increase in non-communicable diseases is expected, and these results have, yet again, identified smoking as a primary risk factor for CVDs. Copyright © 2015 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

Oxygen decline in biotesting of environmental samples--is there a need for consideration in the acute zebrafish embryo assay?

PubMed

Küster, Eberhard; Altenburger, Rolf

2008-12-01

Environmental samples such as groundwater, sediment pore water, native or freeze dried sediments may be difficult to analyze for toxic effects with organismic aquatic bioassays. These samples might evoke low oxygen concentration or oxygen depletion during the test. The toxicity assessment could thus be confounded by low oxygen concentrations. The acute zebrafish embryo assay was used to analyze the influence of oxygen deficit on the embryonic development in the first 48 h post fertilization. Embryos were exposed to varying oxygen concentrations ranging from <30 to >80% oxygen saturation of water. A clear concentration dependent retardation of fish embryo development was observed. Because of a retarded development toxic thresholds of environmental samples which might include substances slowing down the development will be altered. For the purpose of identification of critical contaminants in complex environmental samples, it is proposed to actively aerate environmental samples which are likely to be oxygen depleted during the duration of the zebrafish embryo bioassay. 2008 Wiley Periodicals, Inc.

Disentangling controls on element impurities of bivalve shells

NASA Astrophysics Data System (ADS)

Zhao, Liqiang; Schöne, Bernd R.; Mertz-Kraus, Regina

2017-04-01

Trace and minor elements of bivalve shells can potentially serve as proxies of past environmental change. However, retrieving environmental information from element impurities of bivalve shells remains an extremely challenging task. A central difficulty concerns the fact that extrinsic and intrinsic factors governing the element incorporation are poorly constrained. Within the framework of the ARAMACC project, we aim to decipher the complexity of the incorporation of trace and minor elements into bivalve shells and explore their full potential as proxies of environmental change. More specifically, the following questions were tackled. (1) How are trace and minor elements transported from the ambient environment to the calcifying front? (2) How is their incorporation into the shells affected by environmental and physiological variables? Our findings lend support to the general assumption that divalent ions (e.g., Cu2+, Mn2+, Zn2+ and Pb2+) share the same transport pathways as Ca2+ because of similar ionic radii and electrochemical properties. However, results obtained for Mg2+, Sr2+ and Ba2+ are particularly interesting as they are at odds with existing hypotheses on the incorporation of these three elements, i.e., intracellular Ca2+ pathways (via Ca2+ channels and Ca2+-ATPase) are likely not responsible for their incorporation. Despite the existence of strong physiological interference, some encouraging results were found, in particular (1) strong, positive relationships between the Sr, Ba and Mn contents of the shells and concentrations in the ambient water, (2) only minor effects of growth rate (which is closely linked to the rate of crystal growth and hence, kinetics) on the amounts of Na, Sr, Ba and Mn incorporation into the shells. Overall, our findings demonstrate that environmental and physiological controls on the element incorporation do not have to be mutually exclusive, i.e., if environmental changes outweigh physiological influences, one could still expect that trace and minor elements of bivalve shells serve as promising environmental proxies.

Source, Distribution, and Management of Arsenic in Water from Wells, Eastern San Joaquin Ground-Water Subbasin, California

USGS Publications Warehouse

Izbicki, John A.; Stamos, Christina L.; Metzger, Loren F.; Halford, Keith J.; Kulp, Thomas R.; Bennett, George L.

2008-01-01

Between 1974 and 2001 water from as many as one-third of wells in the Eastern San Joaquin Ground Water Subbasin, about 80 miles east of San Francisco, had arsenic concentrations greater than the U.S. Environmental Protection Agency Maximum Contaminant Level (MCL) for arsenic of 10 micrograms per liter (ug/L). Water from some wells had arsenic concentrations greater than 60 ug/L. The sources of arsenic in the study area include (1) weathering of arsenic bearing minerals, (2) desorption of arsenic associated with iron and manganese oxide coatings on the surfaces of mineral grains at pH's greater than 7.6, and (3) release of arsenic through reductive dissolution of iron and manganese oxide coatings in the absence of oxygen. Reductive dissolution is responsible for arsenic concentrations greater than the MCL. The distribution of arsenic varied areally and with depth. Concentrations were lower near ground-water recharge areas along the foothills of the Sierra Nevada; whereas, concentrations were higher in deeper wells at the downgradient end of long flow paths near the margin of the San Joaquin Delta (fig. 1). Management opportunities to control high arsenic concentrations are present because water from the surface discharge of wells is a mixture of water from the different depths penetrated by wells. On the basis of well-bore flow and depth-dependent water-quality data collected as part of this study, the screened interval of a public-supply well having arsenic concentrations that occasionally exceed the MCL was modified to reduce arsenic concentrations in the surface discharge of the well. Arsenic concentrations from the modified well were about 7 ug/L. Simulations of ground-water flow to the well showed that although upward movement of high-arsenic water from depth within the aquifer occurred, arsenic concentrations from the well are expected to remain below the MCL.

Environmental, health, and safety effects of engineered nanomaterials: challenges and research needs

NASA Astrophysics Data System (ADS)

Fairbrother, Howard

2010-04-01

The number of technologies and consumer products that incorporate engineered nanomaterials (ENMs) has grown rapidly. Indeed, ENMs such as carbon nanotubes and nano-silver, are revolutionizing many commercial technologies and have already been incorporated into more than 800 commercial products, including polymer composites, cell phone batteries, sporting equipment and cosmetics. The global market for ENMs has grown steadily from 7.5 billion in 2003 to 12.7 billion in 2008. Over the next five years, their market value is expected to exceed $27 billion. This surge in demand has been responsible for a corresponding increase in the annual production rates of ENMs. For example, Bayer anticipates that single and multi-walled carbon nanotubes (SWNT and MWNT) production rates will reach 3,000 tons/yr by 2012. Inevitably, some of these synthetic materials will enter the environment either from incidental release during manufacture and transport, or following use and disposal. Consequently, intense scientific research is now being directed towards understanding the environmental, health and safety (EHS) risks posed by ENMs. I will highlight some of the key research challenges and needs in this area, include (i) developing structure-property relationships that will enable physicochemical properties of ENMs to be correlated with environmentally relevant behavior (e.g. colloidal properties, toxicity), (ii) determining the behavior of nanoproducts, and (iii) developing analytical techniques capable of detecting and quantifying the concentration of ENMs in the environment.

Urbanization and health in developing countries.

PubMed

Harpham, T; Stephens, C

1991-01-01

In developing countries the level of urbanization is expected to increase to 39.5% by the end of this century and to 56.9% by 2025. The number of people living in slums and shanty towns represent about one-third of the people living in cities in developing countries. This article focuses upon these poor urban populations and comments upon their lifestyle and their exposure to hazardous environmental conditions which are associated with particular patterns of morbidity and mortality. The concept of marginality has been used to describe the lifestyle of the urban poor in developing countries. This concept is critically examined and it is argued that any concept of the urban poor in developing countries being socially, economically or politically marginal is a myth. However, it can certainly be claimed that in health terms the urban poor are marginal as demonstrated by some of the studies reviewed in this article. Most studies of the health of the urban poor in developing countries concentrate on the environmental conditions in which they live. The environmental conditions of the urban poor are one of the main hazards of the lifestyle of poor urban residents. However, other aspects of their way of life, or lifestyle, have implications for their health. Issues such as smoking, diet, alcohol and drug abuse, and exposure to occupational hazards, have received much less attention in the literature and there is an urgent need for more research in these areas.

Safety concerns for first entry operations of orbiting spacecraft

NASA Technical Reports Server (NTRS)

Wilson, Steven H.; Limero, Thomas F.; James, John T.

1994-01-01

The Space Station Freedom crew will face operational problems unique to the spacecraft environment due to the absence of convection currents and the confined atmosphere within the habitable modules. Airborne contaminants from the materials offgassing or contingency incidents like thermodegradation may accumulate until they reach hazardous concentrations. Flow modeling and experiences from previous space flight missions confirm that caution must be exercised during first-entry operations. A review of the first-entry procedures performed during the Skylab Program will be presented to highlight the necessity for carefully planned operations. Many of the environmental conditions that can be expected on the Space Station are analogous to those which exist in confined storage or work spaces in the industrial setting. Experience with closed-loop environmental operations (e.g., atmospheric control of submarines) have also demonstrated that the buildup of trace contaminant gases could result in conditions that lead to mission termination or loss of crew. Consequently, some first-entry issues for the Station can be addressed by comparing them to familiar techniques developed on Earth. The instruments of the Environmental Health System (EHS) will provide the necessary monitoring capability to protect crew health and safety during the planned first-entry procedures of the MTC phase of the SSF Program. The authors of this paper will describe those procedures and will cite an example of the consequences when proper first-entry procedures are not followed.

Dysregulation of autism-associated synaptic proteins by psychoactive pharmaceuticals at environmental concentrations.

PubMed

Kaushik, Gaurav; Xia, Yu; Pfau, Jean C; Thomas, Michael A

2017-11-20

Autism Spectrum Disorders (ASD) are complex neurological disorders for which the prevalence in the U.S. is currently estimated to be 1 in 50 children. A majority of cases of idiopathic autism in children likely result from unknown environmental triggers in genetically susceptible individuals. These triggers may include maternal exposure of a developing embryo to environmentally relevant minute concentrations of psychoactive pharmaceuticals through ineffectively purified drinking water. Previous studies in our lab examined the extent to which gene sets associated with neuronal development were up- and down-regulated (enriched) in the brains of fathead minnows treated with psychoactive pharmaceuticals at environmental concentrations. The aim of this study was to determine whether similar treatments would alter in vitro expression of ASD-associated synaptic proteins on differentiated human neuronal cells. Human SK-N-SH neuroblastoma cells were differentiated for two weeks with 10μM retinoic acid (RA) and treated with environmentally relevant concentrations of fluoxetine, carbamazepine or venlafaxine, and flow cytometry technique was used to analyze expression of ASD-associated synaptic proteins. Data showed that carbamazepine individually, venlafaxine individually and mixture treatment at environmental concentrations significantly altered the expression of key synaptic proteins (NMDAR1, PSD95, SV2A, HTR1B, HTR2C and OXTR). Data indicated that psychoactive pharmaceuticals at extremely low concentrations altered the in vitro expression of key synaptic proteins that may potentially contribute to neurological disorders like ASD by disrupting neuronal development. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of environmental chemistry on mycogenic Mn oxide minerals

NASA Astrophysics Data System (ADS)

Santelli, C. M.; Farfan, G. A.; Post, A.; Post, J. E.

2012-12-01

Manganese (Mn) oxide minerals are ubiquitous in aquatic and terrestrial environments and their presence can have broad environmental consequences. In particular, Mn oxides scavenge nutrients and metals, degrade complex organics, and oxidize a variety of inorganic contaminants. The "reactivity" of Mn oxides, however, is highly dependent upon crystallite size, composition, and structure, which are largely determined by environmental factors such as solution chemistry. It is has been suggested that most Mn oxides in terrestrial and aquatic environments are formed by microbial activity; indeed, a diversity of Mn(II)-oxidizing bacteria and fungi have been isolated and their mineral byproducts are consistent with those observed in natural systems. Previous studies showed that Mn(II)-oxidizing Ascomycete fungi produce highly-disordered, nanocrystalline Mn oxides that are structurally similar to synthetic δ-MnO2 or natural vernadite. Unlike related studies with Mn-oxidizing bacteria, Mn oxides produced by these fungi did not "age" or transform to more crystalline mineral phases with time. We hypothesize that fungal growth conditions, in particular the low concentration of cations, are inhibiting secondary mineral formation. The overall goal of this research is to examine the structure and speciation of fungally-precipitated Mn oxides with respect to fungal species, time, and concentration of soluble Mn(II), Na, and Ca - three environmentally relevant cations that promote the transformation of δ-MnO2 to more crystalline mineral phases such as feitknechtite, birnessite, or ranciéite. For this study, we examined the Mn oxides formed by different species of Mn(II)-oxidizing fungi (Pyrenochaeta sp., Stagonospora sp., Plectosphaerella cucumerina., and Acremonium strictum). Isolates were grown for 8 or 16 days in a nutrient lean media consisting of yeast extract, trace elements and 0.2 mM MnCl2 supplemented with varying concentrations of Na, Ca, or Mn(II) compounds. The concentration of Mn(II) in solution was held constant (0, 0.15, 0.5, 1.0 and 1.5 mM) only in the Mn-supplemented experiment. Mycogenic Mn oxides were analyzed using X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS). During the experiments, it was observed that each fungal species responded differently to the varying growth media. The addition of Na inhibited growth and oxidation of several species, and the highest concentrations of Mn in solution proved toxic to a few species. Fungi grown with Na produced a highly-disordered phyllomanganate phase similar to birnessite or vernadite. During growth in Ca-rich solutions, however, a more crystalline ranciéite-like phase was formed with 10Å interlayer spacing that collapsed to 7Å upon drying. Although a feitknechtite-like phase was expected in experiments with Mn concentrations greater than 0.5 mM, a birnessite-like phase was formed. This suggests that a more complex solution chemistry is required for transformation to the more crystalline phases, or the presence of the fungal biomass is inhibiting the ripening of the Mn oxides. This information sheds lights on how growth conditions impact the primary (biologically-induced) and secondary (abiotic reactions) mineral products of fungal Mn(II)-oxidation, which ultimately influences the overall impact of these minerals in the environment.

[Effects of urban noise on mental health].

PubMed

Belojević, G; Jakovljević, B; Kocijancić, R; Pjerotić, L; Dimitrijević, J

1995-01-01

The results of the latest studies on the effects of urban noise on mental health are presented in this paper. Numerous psychiatric symptoms have been frequently noticed in the population of the settlements with a high level of urban noise: fatigue, headaches, tension, anxiety, irritability, bad concentration, insomnia, whith a consequently high consumption of psychotropic medicines. Higher admission rates in psychiatric hospitals have been noticed from noisy areas in comparison with low noise regions. By use of diagnostic psychiatric interviews it has been shown as well, that in sensitive categories of population positive correlation can be expected between the number of persons with mental disorder and the level of environmental noise. Noise annoyance and sleep disturbance, namely shortening or absence of the sleep phase 4 and REM, are the basic negative psychological effects of noise, with an adverse effect on mental health in general.

Data-Mining and Informatics Approaches for Environmental Contaminants

EPA Science Inventory

New and emerging environmental contaminants are chemicals that have not been previously detected or that are being detected at levels significantly different from those expected in both biological and ecological arenas (that is, human, wildlife, and environment). Many chemicals c...

Service Area Market Analysis: Environmental Scanning.

ERIC Educational Resources Information Center

Front Range Community Coll., Westminster, CO.

This environmental scanning report presents, in brief, various key indicators: political climate, population demographics, secondary education, postsecondary education, welfare, unemployment, industry, labor, and general conclusions. General conclusions made in this report are as follows: higher education is expected to receive a slight increase…

78 FR 6141 - Information Collection Activities: Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-29

... use a telecommunications device for the deaf (TDD) may call the Federal Information Relay Service.... SUPPLEMENTARY INFORMATION: Title of Collection: Antarctic emergency response plan and environmental protection... information on their environmental protection obligations under the Antarctic Conservation Act. Expected...

Spatial patterns and environmental controls of particulate organic carbon in surface waters in the conterminous United States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Qichun; Zhang, Xuesong; Xu, Xingya

2016-06-01

Carbon stocks and fluxes in inland waters have been identified as important, but poorly constrained components of the global carbon cycle. In this study, we compile and analyze particulate organic carbon (POC) concentration data from 1145 U.S. Geological Survey (USGS) hydrologic stations to investigate the spatial variability and environmental controls of POC concentration. We observe substantial spatial variability in POC concentration (1.43 ± 2.56 mg C/ L, Mean ± Standard Deviation), with the Upper Mississippi River basin and the Piedmont region in the eastern U.S. having the highest POC concentration. Further, we employ generalized linear regression models to analyze themore » impacts of sediment transport and algae growth as well as twenty-one other environmental factors on the POC variability. Suspended sediment and chlorophyll-a explain 26% and 17% of the variability in POC concentration, respectively. At the national level, the twenty-one selected environmental factors combined can explain ca. 40% of the spatial variance in POC concentration. Overall, urban area and soil clay content show significant negative correlation with POC concentration, while soil water content and soil bulk density correlate positively with POC. In addition, total phosphorus concentration and dam density covariate positively with POC concentration. Furthermore, regional scale analyses reveal substantial variation in environmental controls determining POC concentration across the 18 major water resource regions in the U.S. The POC concentration and associated environmental controls also vary non-monotonically with river order. These findings indicate complex interactions among multiple factors in regulating POC production over different spatial scales and across various sections of the river networks. This complexity together with the large unexplained uncertainty highlight the need for consideration of non-linear processes that control them and developing appropriate methodologies to track the transformation and transport of carbon in these terrestrial-aquatic systems. Such scientific advancements will also benefit greatly the Earth system models that are currently deficient in representing properly this component of global carbon cycle.« less

Environmental variability and population dynamics: Do European and North American ducks play by the same rules?

USGS Publications Warehouse

Pöysä, Hannu; Rintala, Jukka; Johnson, Douglas H.; Kauppinen, Jukka; Lammi, Esa; Nudds, Thomas D.; Väänänen, Veli-Matti

2016-01-01

Density dependence, population regulation, and variability in population size are fundamental population processes, the manifestation and interrelationships of which are affected by environmental variability. However, there are surprisingly few empirical studies that distinguish the effect of environmental variability from the effects of population processes. We took advantage of a unique system, in which populations of the same duck species or close ecological counterparts live in highly variable (north American prairies) and in stable (north European lakes) environments, to distinguish the relative contributions of environmental variability (measured as between-year fluctuations in wetland numbers) and intraspecific interactions (density dependence) in driving population dynamics. We tested whether populations living in stable environments (in northern Europe) were more strongly governed by density dependence than populations living in variable environments (in North America). We also addressed whether relative population dynamical responses to environmental variability versus density corresponded to differences in life history strategies between dabbling (relatively “fast species” and governed by environmental variability) and diving (relatively “slow species” and governed by density) ducks. As expected, the variance component of population fluctuations caused by changes in breeding environments was greater in North America than in Europe. Contrary to expectations, however, populations in more stable environments were not less variable nor clearly more strongly density dependent than populations in highly variable environments. Also, contrary to expectations, populations of diving ducks were neither more stable nor stronger density dependent than populations of dabbling ducks, and the effect of environmental variability on population dynamics was greater in diving than in dabbling ducks. In general, irrespective of continent and species life history, environmental variability contributed more to variation in species abundances than did density. Our findings underscore the need for more studies on populations of the same species in different environments to verify the generality of current explanations about population dynamics and its association with species life history.

Environmental variability and population dynamics: do European and North American ducks play by the same rules?

PubMed

Pöysä, Hannu; Rintala, Jukka; Johnson, Douglas H; Kauppinen, Jukka; Lammi, Esa; Nudds, Thomas D; Väänänen, Veli-Matti

2016-10-01

Density dependence, population regulation, and variability in population size are fundamental population processes, the manifestation and interrelationships of which are affected by environmental variability. However, there are surprisingly few empirical studies that distinguish the effect of environmental variability from the effects of population processes. We took advantage of a unique system, in which populations of the same duck species or close ecological counterparts live in highly variable (north American prairies) and in stable (north European lakes) environments, to distinguish the relative contributions of environmental variability (measured as between-year fluctuations in wetland numbers) and intraspecific interactions (density dependence) in driving population dynamics. We tested whether populations living in stable environments (in northern Europe) were more strongly governed by density dependence than populations living in variable environments (in North America). We also addressed whether relative population dynamical responses to environmental variability versus density corresponded to differences in life history strategies between dabbling (relatively "fast species" and governed by environmental variability) and diving (relatively "slow species" and governed by density) ducks. As expected, the variance component of population fluctuations caused by changes in breeding environments was greater in North America than in Europe. Contrary to expectations, however, populations in more stable environments were not less variable nor clearly more strongly density dependent than populations in highly variable environments. Also, contrary to expectations, populations of diving ducks were neither more stable nor stronger density dependent than populations of dabbling ducks, and the effect of environmental variability on population dynamics was greater in diving than in dabbling ducks. In general, irrespective of continent and species life history, environmental variability contributed more to variation in species abundances than did density. Our findings underscore the need for more studies on populations of the same species in different environments to verify the generality of current explanations about population dynamics and its association with species life history.

Development and implementation of a regression model for predicting recreational water quality in the Cuyahoga River, Cuyahoga Valley National Park, Ohio 2009-11

USGS Publications Warehouse

Brady, Amie M.G.; Plona, Meg B.

2012-01-01

The Cuyahoga River within Cuyahoga Valley National Park (CVNP) is at times impaired for recreational use due to elevated concentrations of Escherichia coli (E. coli), a fecal-indicator bacterium. During the recreational seasons of mid-May through September during 2009–11, samples were collected 4 days per week and analyzed for E. coli concentrations at two sites within CVNP. Other water-quality and environ-mental data, including turbidity, rainfall, and streamflow, were measured and (or) tabulated for analysis. Regression models developed to predict recreational water quality in the river were implemented during the recreational seasons of 2009–11 for one site within CVNP–Jaite. For the 2009 and 2010 seasons, the regression models were better at predicting exceedances of Ohio's single-sample standard for primary-contact recreation compared to the traditional method of using the previous day's E. coli concentration. During 2009, the regression model was based on data collected during 2005 through 2008, excluding available 2004 data. The resulting model for 2009 did not perform as well as expected (based on the calibration data set) and tended to overestimate concentrations (correct responses at 69 percent). During 2010, the regression model was based on data collected during 2004 through 2009, including all of the available data. The 2010 model performed well, correctly predicting 89 percent of the samples above or below the single-sample standard, even though the predictions tended to be lower than actual sample concentrations. During 2011, the regression model was based on data collected during 2004 through 2010 and tended to overestimate concentrations. The 2011 model did not perform as well as the traditional method or as expected, based on the calibration dataset (correct responses at 56 percent). At a second site—Lock 29, approximately 5 river miles upstream from Jaite, a regression model based on data collected at the site during the recreational seasons of 2008–10 also did not perform as well as the traditional method or as well as expected (correct responses at 60 percent). Above normal precipitation in the region and a delayed start to the 2011 sampling season (sampling began mid-June) may have affected how well the 2011 models performed. With these new data, however, updated regression models may be better able to predict recreational water quality conditions due to the increased amount of diverse water quality conditions included in the calibration data. Daily recreational water-quality predictions for Jaite were made available on the Ohio Nowcast Web site at www.ohionowcast.info. Other public outreach included signage at trailheads in the park, articles in the park's quarterly-published schedule of events and volunteer newsletters. A U.S. Geological Survey Fact Sheet was also published to bring attention to water-quality issues in the park.

Environmental change makes robust ecological networks fragile

PubMed Central

Strona, Giovanni; Lafferty, Kevin D.

2016-01-01

Complex ecological networks appear robust to primary extinctions, possibly due to consumers' tendency to specialize on dependable (available and persistent) resources. However, modifications to the conditions under which the network has evolved might alter resource dependability. Here, we ask whether adaptation to historical conditions can increase community robustness, and whether such robustness can protect communities from collapse when conditions change. Using artificial life simulations, we first evolved digital consumer-resource networks that we subsequently subjected to rapid environmental change. We then investigated how empirical host–parasite networks would respond to historical, random and expected extinction sequences. In both the cases, networks were far more robust to historical conditions than new ones, suggesting that new environmental challenges, as expected under global change, might collapse otherwise robust natural ecosystems. PMID:27511722

Mineralogy and the release of trace elements from slag from the Hegeler Zinc smelter, Illinois (USA)

USGS Publications Warehouse

Piatak, Nadine M.; Seal, Robert R.

2010-01-01

Slag from the former Hegeler Zn-smelting facility in Illinois (USA) is mainly composed of spinifex Ca-rich plagioclase, fine-grained dendritic or coarse-grained subhedral to anhedral clinopyroxenes, euhedral to subhedral spinels, spherical blebs of Fe sulfides, silicate glass, and less commonly fayalitic olivine. Mullite and quartz were also identified in one sample as representing remnants of the furnace lining. Secondary phases such as goethite, hematite and gypsum are significant in some samples and reflect surficial weathering of the dump piles or represent byproducts of roasting. A relatively rare Zn-rich material contains anhedral willemite, subhedral gahnite, massive zincite, hardystonite and a Zn sulfate (brianyoungite), among other phases, and likely represents the molten content of the smelting furnace before Zn extraction. The bulk major-element chemistry of most slag samples is dominated by SiO2, Al2O3, Fe2O3 and CaO. The bulk composition of the slag suggests a high viscosity of the melt and the mineralogy suggests a high silica content of the melt. Bulk slag trace-element chemistry shows that the dominant metal is Zn with >28.4 wt.% in the Zn-rich material and between 212 and 14,900 mg/kg in the other slags. The concentrations of other trace elements reach the following: 45 mg/kg As, 1170 mg/kg Ba, 191 mg/kg Cd, 242 mg/kg Co, 103 mg/kg Cr, 6360 mg/kg Cu, 107 mg/kg Ni, and 711 mg/kg Pb.Zinc, as the dominant metal in the slags, is likely the most environmentally significant metal in these samples; Cd, Cu, and Pb are also of concern and their concentrations exceed US Environmental Protection Agency preliminary remediation goals for residential soils. Spinel was found to be the dominant concentrator of Zn for samples containing significant Zn (>1 wt.%); the silicate glass also contained relatively high concentrations of Zn compared to other phases. Zinc partitioned into the silicates and oxides in these samples is generally more resistant to weathering and therefore less leached when compared to the slag samples with lower bulk Zn concentrations where Zn is likely partitioned into volumetrically minor sulfides. This is confirmed by leachate tests that resulted in low leachate Zn concentrations for samples with Zn partitioned into spinel. In contrast, the concentrations of Zn and SO4 are close to those expected from the dissolution of stoichiometric ZnS in leachates from samples in which the dominant host of Zn is suspected to be sulfides. The fact that Zn and other metals occur commonly as sulfides, which are more reactive than the silicates and oxides into which they dominantly partition according to other slag studies, indicates the Hegeler slag pile may be more of an environmental concern than other slag piles.

Environmentally relevant concentrations of nitrate increase plasma testosterone concentrations in female American alligators (Alligator mississippiensis).

PubMed

Hamlin, Heather J; Edwards, Thea M; McCoy, Jessica; Cruze, Lori; Guillette, Louis J

2016-11-01

Anthropogenic nitrogen is a ubiquitous environmental contaminant that is contributing to the degradation of freshwater, estuarine, and coastal ecosystems worldwide. The effects of environmental nitrate, a principal form of nitrogen, on the health of aquatic life is of increasing concern. We exposed female American alligators to three concentrations of nitrate (0.7, 10 and 100mg/L NO 3 -N) for a duration of five weeks and five months from hatch. We assessed growth, plasma sex steroid and thyroid hormone concentrations, and transcription levels of key genes involved in steroidogenesis (StAR, 3β-HSD, and P450 scc ) and hepatic clearance (Cyp1a, Cyp3a). Exposure to 100mg/L NO 3 -N for both five weeks and five months resulted in significantly increased plasma testosterone (T) concentrations compared with alligators in the reference treatment. No differences in 17β-estradiol, progesterone, or thyroid hormones were observed, nor were there differences in alligator weight or the mRNA abundance of steroidogenic or hepatic genes. Plasma and urinary nitrate concentrations increased with increasing nitrate treatment levels, although relative plasma concentrations of nitrate were significantly lower in five month, versus five week old animals, possibly due to improved kidney function in older animals. These results indicate that environmentally relevant concentrations of nitrate can increase circulating concentrations of T in young female alligators. Copyright © 2016 Elsevier Inc. All rights reserved.

Framing sound: Using expectations to reduce environmental noise annoyance.

PubMed

Crichton, Fiona; Dodd, George; Schmid, Gian; Petrie, Keith J

2015-10-01

Annoyance reactions to environmental noise, such as wind turbine sound, have public health implications given associations between annoyance and symptoms related to psychological distress. In the case of wind farms, factors contributing to noise annoyance have been theorised to include wind turbine sound characteristics, the noise sensitivity of residents, and contextual aspects, such as receiving information creating negative expectations about sound exposure. The experimental aim was to assess whether receiving positive or negative expectations about wind farm sound would differentially influence annoyance reactions during exposure to wind farm sound, and also influence associations between perceived noise sensitivity and noise annoyance. Sixty volunteers were randomly assigned to receive either negative or positive expectations about wind farm sound. Participants in the negative expectation group viewed a presentation which incorporated internet material indicating that exposure to wind turbine sound, particularly infrasound, might present a health risk. Positive expectation participants viewed a DVD which framed wind farm sound positively and included internet information about the health benefits of infrasound exposure. Participants were then simultaneously exposed to sub-audible infrasound and audible wind farm sound during two 7 min exposure sessions, during which they assessed their experience of annoyance. Positive expectation participants were significantly less annoyed than negative expectation participants, while noise sensitivity only predicted annoyance in the negative group. Findings suggest accessing negative information about sound is likely to trigger annoyance, particularly in noise sensitive people and, importantly, portraying sound positively may reduce annoyance reactions, even in noise sensitive individuals. Copyright © 2015 Elsevier Inc. All rights reserved.

An analysis on the environmental Kuznets curve of Chengdu

NASA Astrophysics Data System (ADS)

Gao, Zijian; Peng, Yue; Zhao, Yue

2017-12-01

In this paper based on the environmental and economic data of Chengdu from 2005 to 2014, the measurement models were established to analyze 3 kinds of environmental flow indicators and 4 kinds of environmental stock indicators to obtain their EKC evolution trajectories and characters. The results show that the relationship curve between the discharge of SO2 from industry and the GDP per capita is a positive U shape, just as the curve between discharge of COD from industry and the GDP per person. The relationship curve between the dust discharge from industry and the GDP per capita is an inverted N shape. In the central of the urban the relationship curve between the concentration of SO2 in the air and the GDP per person is a positive U shape. The relationship curves between the concentration of NO2 in the air and the GDP per person, between the concentration of the particulate matters and the GDP per person, and between the concentration of the fallen dusts and the GDP per person are fluctuating. So the EKC curves of the 7 kinds of environmental indicators are not accord with inverted U shape feature. In the development of this urban the environmental problems can’t be resolved only by economic growth. The discharge of industrial pollutants should be controlled to improve the atmospheric environmental quality and reduce the environmental risks.

Combining exposure and effect modeling into an integrated probabilistic environmental risk assessment for nanoparticles.

PubMed

Jacobs, Rianne; Meesters, Johannes A J; Ter Braak, Cajo J F; van de Meent, Dik; van der Voet, Hilko

2016-12-01

There is a growing need for good environmental risk assessment of engineered nanoparticles (ENPs). Environmental risk assessment of ENPs has been hampered by lack of data and knowledge about ENPs, their environmental fate, and their toxicity. This leads to uncertainty in the risk assessment. To deal with uncertainty in the risk assessment effectively, probabilistic methods are advantageous. In the present study, the authors developed a method to model both the variability and the uncertainty in environmental risk assessment of ENPs. This method is based on the concentration ratio and the ratio of the exposure concentration to the critical effect concentration, both considered to be random. In this method, variability and uncertainty are modeled separately so as to allow the user to see which part of the total variation in the concentration ratio is attributable to uncertainty and which part is attributable to variability. The authors illustrate the use of the method with a simplified aquatic risk assessment of nano-titanium dioxide. The authors' method allows a more transparent risk assessment and can also direct further environmental and toxicological research to the areas in which it is most needed. Environ Toxicol Chem 2016;35:2958-2967. © 2016 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC. © 2016 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.

Evaluation of toxic and interactive toxic effects of three agrochemicals and copper using a battery of microbiotests.

PubMed

Kungolos, A; Emmanouil, C; Tsiridis, V; Tsiropoulos, N

2009-08-01

Three commonly used test organisms of different trophic levels (Vibrio fischeri, Pseudokirchneriella subcapitata and Daphnia magna) were exposed to selected agrochemicals (fosthiazate, metalaxyl-M, imidacloprid) and copper, in single doses or in binary mixtures. The toxicity of each single compound varied up to two orders of magnitude, depending on the test species examined. V. fischeri was the most sensitive test organism regarding fosthiazate and metalaxyl-M, indicating an IC(50) value of 0.20 mg/L (0.17-0.25 mg/L) and 0.88 mg/L (0.35-1.57 mg/L), respectively. Imidacloprid was the least toxic compound, indicating an EC(50) value on D. magna of 64.6 mg/L (43.3-122.5 mg/L) and an IC(50) value on V. fischeri of 226 mg/L (159-322 mg/L), while for imidacloprid at a concentration of 1000 mg/L the effect on P. subcapitata was lower than 50%. Copper was the most toxic compound towards all test organisms exhibiting the highest toxic effect on P. subcapitata, with an IC(50) value of 0.05 mg/L (0.003-0.008 mg/L). The toxic effects of the binary mixtures have been compared to the theoretically expected effect, resulting from a simple mathematical model based on the theory of probabilities. The independent action model was used in order to predict the theoretically expected effect. The interactive effects were mostly antagonistic or additive, while in few cases (interactive effects of metalaxyl-M and copper on V. fischeri) a synergistic mode of action was observed for some concentration combinations. Experiments showed that interactive effects of chemicals may vary depending on the test species used as well as on the chemicals and their respective concentrations. Although most of the concentrations of chemicals tested in this study are higher than the ones usually found in natural environment, the evaluation of their interactive toxic effects using a battery of bioassays may comprise a useful tool for the estimation of the environmental hazard of chemicals.

Air quality improvements using European environment policies: a case study of SO2 in a coastal region in Portugal.

PubMed

Pereira, M C; Santos, R C; Alvim-Ferraz, M C M

2007-02-01

The European Union (EU) has defined several efforts for preventing and controlling air pollution that have led to a generalized reduction of health risks and environmental effects. One example of these efforts was the establishment of legislation that imposed a reduction of sulfur content in fuels, switching to cleaner fuels for industry and motor vehicles (Auto-Oil Directives). The goal of this study was to evaluate the first trends in the air quality of Oporto Metropolitan Area (Oporto-MA) related to implementation of these directives in Portugal since 2000. Therefore, sulfur dioxide (SO2) concentration data from air quality monitoring sites were analyzed for the period 1999 through 2003. It was observed that daily SO2 concentrations in the industrial area are much higher than those of the urban and rural areas, reflecting the influence of the industrial sector. The annual SO2 concentrations for the consecutive years of analysis decreased considerably for all the monitoring sites. A considerable decrease in SO2 emissions was also observed for the same period. According to EU legislation, the exceedances of the SO2 recommended limit values decreased significantly. In conclusion, this analysis shows evidence that SO2 concentrations are decreasing, and that this is consistent with the implementation of the legislation and control of the sources of pollution. Nevertheless, the potential for human health risks still persists, particularly in industrialized areas. It is expected that SO2 concentration levels in ambient air of Oporto-MA will continue to decrease in the coming years, following the present European trends.

Observations of high droplet number concentrations in Southern Ocean boundary layer clouds

NASA Astrophysics Data System (ADS)

Chubb, T.; Huang, Y.; Jensen, J.; Campos, T.; Siems, S.; Manton, M.

2015-09-01

Data from the standard cloud physics payload during the NSF/NCAR High-performance Instrumented Airborne Platform for Environmental Research (HIAPER) Pole-to-Pole Observations (HIPPO) campaigns provide a snapshot of unusual wintertime microphysical conditions in the boundary layer over the Southern Ocean. On 29 June 2011, the HIAPER sampled the boundary layer in a region of pre-frontal warm air advection between 58 and 48° S to the south of Tasmania. Cloud droplet number concentrations were consistent with climatological values in the northernmost profiles but were exceptionally high for wintertime in the Southern Ocean at 100-200 cm-3 in the southernmost profiles. Sub-micron (0.0625 m s-1) were most likely responsible for production of sea spray aerosol which influenced the microphysical properties of the boundary layer clouds. The smaller size and higher number concentration of cloud droplets is inferred to increase the albedo of these clouds, and these conditions occur regularly, and are expected to increase in frequency, over windy parts of the Southern Ocean.

Environmental exposure modeling and monitoring of human pharmaceutical concentrations in the environment

USGS Publications Warehouse

Versteeg, D.J.; Alder, A. C.; Cunningham, V. L.; Kolpin, D.W.; Murray-Smith, R.; Ternes, T.

2005-01-01

Human pharmaceuticals are receiving increased attention as environmental contaminants. This is due to their biological activity and the number of monitoring programs focusing on analysis of these compounds in various environmental media and compartments. Risk assessments are needed to understand the implications of reported concentrations; a fundamental part of the risk assessment is an assessment of environmental exposures. The purpose of this chapter is to provide guidance on the use of predictive tools (e.g., models) and monitoring data in exposure assessments for pharmaceuticals in the environment. Methods to predict environmental concentrations from equations based on first principles are presented. These equations form the basis of existing GIS (geographic information systems)-based systems for understanding the spatial distribution of pharmaceuticals in the environment. The pharmaceutical assessment and transport (PhATE), georeferenced regional exposure assessment tool for European rivers (GREAT-ER), and geographical information system (GIS)-ROUT models are reviewed and recommendations are provided concerning the design and execution of monitoring studies. Model predictions and monitoring data are compared to evaluate the relative utility of each approach in environmental exposure assessments. In summary, both models and monitoring data can be used to define representative exposure concentrations of pharmaceuticals in the environment in support of environmental risk assessments.

Spatial pattern of hormone and antibiotic concentrations in surface waters in Delaware

NASA Astrophysics Data System (ADS)

Vaicunas, R.; Inamdar, S. P.; Dutta, S.; Aga, D.; Zimmerman, L. R.

2011-12-01

Water quality surveys of the U.S. have confirmed the presence of hormones and antibiotics in some surface waters. Although the reported concentrations of these substances are extremely low, there is substantial concern about their effect on aquatic species. For example, chronic exposure to estradiol (E2β) concentrations as low as 40 ng/L have been shown to cause endocrine disruption in fish. Furthermore, there is potential for contaminants to enter our drinking supply. Significant sources of hormones and antibiotics include discharge from concentrated animal feeding operations (CAFOs) and wastewater treatment plants as well as runoff from agricultural land receiving application of animal manure. Since Sussex County, Delaware is one of the leading poultry producing counties in the nation, and many farmers in the state use poultry litter as fertilizer for their crops, it is critical to study the concentrations of contaminants in surface waters. Fifty surface water (streams, lakes, and ponds) sampling locations throughout the state of Delaware were chosen based on DNREC (Delaware Department of Natural Resources and Environmental Control) data. Locations with the highest nitrogen and phosphorus levels were assumed to be associated with agriculture and wastewater sources and therefore were likely to be contaminated with hormones and antibiotics. The first set of sampling occurred in April representing high-flow conditions, and the second set will occur in September representing low-flow conditions. Water samples will be screened through the cost-effective enzyme-linked immunosorbent assay (ELISA) method followed by more rigorous analyses of selected samples using liquid chromatography-mass spectrometry (LC/MS/MS). ELISA screening includes estradiol (E2β), sulfamethazine and triclosan, while LC/MS/MS will quantify both free and conjugated forms of estrone (E1), estradiol (E2β), estriol (E3), as well as selected sulfa and tetracycline antibiotics. Initial ELISA results indicate a range of 0-40 ng/L for E2β, 0-18 μg/L for sulfamethazine, and 0-3 μg/L for triclosan; however, previous studies have shown that the ELISA method tends to overestimate due to cross-reactivity and matrix effects, and therefore we expect lower concentrations from LC/MS/MS. All LC/MS/MS results are expected by December 2011. Results will be compared to the predicted no-effect concentrations to determine whether these contaminants pose a threat to aquatic species and wildlife. ArcGIS was used to plot the measured concentrations on the Delaware state map to provide a spatial representation of the potential contamination. Watersheds were delineated for each of the sampling locations, and land use, physical characteristics of the land, and potential sources of contaminants within the watersheds have been analyzed to explore any relationships with measured contaminant concentrations.

Gap analysis for forest productivity research investments

Treesearch

E.D. Vance

2010-01-01

The US forest sector is in the midst of an era of transition and opportunity. Expectations that forests are managed to sustain wildlife, water, soil, and other environmental values are increasing as are certification systems and state and national initiatives designed to insure those expectations are met.

OLDER ADULTS: AN ENVIRONMENTALLY SUSCEPTIBLE POPULATION

EPA Science Inventory

The baby boom generation is quickly becoming the geriatric generation. The over-65 age bracket hit 13% of Americans in 1997, and is expected to reach 20% by 2030 accounting for 73 million Americans. World-wide the total number of older people (>60years) is expected to double from...

Lichens as environmental risk detectors

NASA Astrophysics Data System (ADS)

Caridi, F.; D'Agostino, M.; Messina, M.; Marcianò, G.; Grioli, L.; Belvedere, A.; Marguccio, S.; Belmusto, G.

2017-04-01

Several studies carried out after the Chernobyl nuclear accident in 1986 showed that lichens are suitable biomonitors of the fall-out, given their long life expectancy. 137Cs activity concentrations were measured through HPGe gamma spectrometry in different epiphytic lichens ( Usnea SPP, Platismatia glauca, Pseudevernia furfuracea, Ramalina SPP), collected from three sampling sites in the Calabria region, south of Italy. Data on variations in the contents of airborne particulates heavy metals, As, Be, Cd, Cu, Hg, Pb and Zn, measured in the thalli of the investigated lichens through inductively coupled plasma mass spectrometry (ICP-MS), were reported in accordance with a lichen thalli naturalness/alteration scale. Energy-dispersive X-ray microanalysis in a scanning electron microscope (SEM-EDX), with an electron beam of 20keV, that interacts with the sample leading to the emission of characteristic X-rays as secondary radiation, was also employed to investigate about the chemistry of the adherent particles to the surface of investigated lichens and about the possible interaction between them and the surrounding environment. Data obtained in this article provide useful information on the environmental risk of the studied area and can be further used for a radiological and chemical mapping.

Coal hydrogenation and environmental health.

PubMed Central

Wadden, R A

1976-01-01

Planning of coal hydrogenation processes, such as liquifaction and gasification, requires consideration of public health implications. Commercial plants will require coal quantities greater than or equal to 20,000 tons/day and the large size of these plants calls for careful consideration of the potential health hazards from the wastes and products of such processes. Analysis of pollution potential can roughly be divided into three categories: raw material structure and constituents, process design, and mode of plant operation. Identifiable pollutants include hydrogen cyanide, phenols, cresols, carbonyl and hydrogen sulfides, ammonia, mercaptans, thiocyanides, aniline, arsenic, trace metals and various polycyclic hydrocarbons. One study of workers in a hydrogenation process has revealed an incidence of skin cancer 16-37 times that expected in the chemical industry. In addition, a number of high boiling point liquid products were identified as being carcinogenic, and air concentrations of benzo[a]pyrene up to 18,000 mug/1000 m3 were reported. Health statistics on occupational groups in other coal conversion industries have shown significantly higher lung cancer rates, relative to groups without such occupational exposures. These data suggest that coal hydrogenation plants must be carefully planned and controlled to avoid harm to environmentally and occupationally exposed populations. PMID:789066

Use of probability analysis to establish routine bioassay screening levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carbaugh, E.H.; Sula, M.J.; McFadden, K.M.

1990-09-01

Probability analysis was used by the Hanford Internal Dosimetry Program to establish bioassay screening levels for tritium and uranium in urine. Background environmental levels of these two radionuclides are generally detectable by the highly sensitive urine analysis procedures routinely used at Hanford. Establishing screening levels requires balancing the impact of false detection with the consequence of potentially undetectable occupation dose. To establish the screening levels, tritium and uranium analyses were performed on urine samples collected from workers exposed only to environmental sources. All samples were collected at home using a simulated 12-hour protocol for tritium and a simulated 24-hour collectionmore » protocol for uranium. Results of the analyses of these samples were ranked according to tritium concentration or total sample uranium. The cumulative percentile was calculated and plotted using log-probability coordinates. Geometric means and screening levels corresponding to various percentiles were estimated by graphical interpolation and standard calculations. The potentially annual internal dose associated with a screening level was calculated. Screening levels were selected corresponding to the 99.9 percentile, implying that, on the average, 1 out of 1000 samples collected from an unexposed worker population would be expected to exceed the screening level. 4 refs., 2 figs.« less

10 CFR 611.106 - Environmental requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... significant environmental effects expected to occur as a result of the project; (3) Identify the effects of... cumulative effects resulting from existing or reasonably foreseeable projects; (4) Identify measures proposed... on-site manpower requirements and payroll during construction and operation, including the number of...

10 CFR 611.106 - Environmental requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... significant environmental effects expected to occur as a result of the project; (3) Identify the effects of... cumulative effects resulting from existing or reasonably foreseeable projects; (4) Identify measures proposed... on-site manpower requirements and payroll during construction and operation, including the number of...

10 CFR 611.106 - Environmental requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... significant environmental effects expected to occur as a result of the project; (3) Identify the effects of... cumulative effects resulting from existing or reasonably foreseeable projects; (4) Identify measures proposed... on-site manpower requirements and payroll during construction and operation, including the number of...

10 CFR 611.106 - Environmental requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... significant environmental effects expected to occur as a result of the project; (3) Identify the effects of... cumulative effects resulting from existing or reasonably foreseeable projects; (4) Identify measures proposed... on-site manpower requirements and payroll during construction and operation, including the number of...

10 CFR 611.106 - Environmental requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... significant environmental effects expected to occur as a result of the project; (3) Identify the effects of... cumulative effects resulting from existing or reasonably foreseeable projects; (4) Identify measures proposed... on-site manpower requirements and payroll during construction and operation, including the number of...

Environmental Scanning, Vancouver Community College.

ERIC Educational Resources Information Center

Yao, Min

This 1994 environmental scanning report from Vancouver Community College (VCC) reviews the expected effects of the separation of VCC into a new Vancouver Community College and Langara College (LC). The report examines the projected service area student-intake capacity; student characteristics; population growth trends; other postsecondary…

Parental Concern about Environmental Chemical Exposures and Children's Urinary Concentrations of Phthalates and Phenols.

PubMed

Pell, Tripler; Eliot, Melissa; Chen, Aimin; Lanphear, Bruce P; Yolton, Kimberly; Sathyanarayana, Sheela; Braun, Joseph M

2017-07-01

To examine whether parents' concerns about environmental chemical exposures were associated with urinary phthalate and phenol concentrations in their school-age children. In a prospective cohort of 218 mother-child pairs from Cincinnati, Ohio (2010-2014), we measured 11 phthalate metabolites and 5 phenols in urine samples when children were age 8 years and used questionnaire data from caregivers. We estimated the covariate-adjusted percent difference in phthalates and phenols among children of parents who expressed concern about environmental chemical exposures compared with children whose parents did not. Concentrations of 4 phthalates, bisphenol S, and bisphenol A were lower among children whose parents expressed concern about environmental chemicals (n = 122) compared with those who did not (n = 96). Di-2-ethylhexyl phthalate metabolites, bisphenol S, and bisphenol A concentrations were 23% (95% CI -38, -5), 37% (95% CI -49, -21), and 13% (95% CI -26, 3) lower, respectively, among children whose parents expressed concern compared with those whose parents did not. Triclosan concentrations were 35% greater (95% CI -2, 87) among children whose parents expressed concern compared with children whose parents did not. Parental concern about environmental chemicals was associated with lower childhood urine concentrations of several phthalates and phenols; unexpectedly, parental concern was associated with greater triclosan concentrations. These results suggest that parental concern may be an important factor in mitigating children's phthalate and phenol exposures. Copyright © 2017 Elsevier Inc. All rights reserved.

Nonparametric estimation of groundwater residence time distributions: What can environmental tracer data tell us about groundwater residence time?

NASA Astrophysics Data System (ADS)

McCallum, James L.; Engdahl, Nicholas B.; Ginn, Timothy R.; Cook, Peter. G.

2014-03-01

Residence time distributions (RTDs) have been used extensively for quantifying flow and transport in subsurface hydrology. In geochemical approaches, environmental tracer concentrations are used in conjunction with simple lumped parameter models (LPMs). Conversely, numerical simulation techniques require large amounts of parameterization and estimated RTDs are certainly limited by associated uncertainties. In this study, we apply a nonparametric deconvolution approach to estimate RTDs using environmental tracer concentrations. The model is based only on the assumption that flow is steady enough that the observed concentrations are well approximated by linear superposition of the input concentrations with the RTD; that is, the convolution integral holds. Even with large amounts of environmental tracer concentration data, the entire shape of an RTD remains highly nonunique. However, accurate estimates of mean ages and in some cases prediction of young portions of the RTD may be possible. The most useful type of data was found to be the use of a time series of tritium. This was due to the sharp variations in atmospheric concentrations and a short half-life. Conversely, the use of CFC compounds with smoothly varying atmospheric concentrations was more prone to nonuniqueness. This work highlights the benefits and limitations of using environmental tracer data to estimate whole RTDs with either LPMs or through numerical simulation. However, the ability of the nonparametric approach developed here to correct for mixing biases in mean ages appears promising.

Endocrine phenotype, reproductive success and survival in the great tit, Parus major.

PubMed

Ouyang, J Q; Sharp, P; Quetting, M; Hau, M

2013-09-01

A central goal in evolutionary ecology is to characterize and identify selection patterns on the optimal phenotype in different environments. Physiological traits, such as hormonal responses, provide important mechanisms by which individuals can adapt to fluctuating environmental conditions. It is therefore expected that selection shapes hormonal traits, but the strength and the direction of selection on plastic hormonal signals are still under investigation. Here, we determined whether, and in which way, selection is acting on the hormones corticosterone and prolactin by characterizing endocrine phenotypes and their relationship with fitness in free-living great tits, Parus major. We quantified variation in circulating concentrations of baseline and stress-induced corticosterone and in prolactin during the prebreeding (March) and the breeding season (May) for two consecutive years, and correlated these with reproductive success (yearly fledgling number) and overwinter survival in female and male individuals. In both years, individuals with high baseline corticosterone concentrations in March had the highest yearly fledgling numbers; while in May, individuals with low baseline corticosterone had the highest yearly reproductive success. Likewise, individuals that displayed strong seasonal plasticity in baseline corticosterone concentrations (high in March and low in May) had the highest reproductive success in each year. Prolactin concentrations were not related to reproductive success, but were positively correlated to the proximity to lay. Between-year plasticity in stress-induced corticosterone concentrations of males was related to yearly variation in food abundance, but not to overall reproductive success. These findings suggest that seasonally alternating directional selection is operating on baseline corticosterone concentrations in both sexes. The observed between-year consistency in selection patterns indicates that a one-time hormone sample in a given season can allow the prediction of individual fitness. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

Prediction of CO concentrations based on a hybrid Partial Least Square and Support Vector Machine model

NASA Astrophysics Data System (ADS)

Yeganeh, B.; Motlagh, M. Shafie Pour; Rashidi, Y.; Kamalan, H.

2012-08-01

Due to the health impacts caused by exposures to air pollutants in urban areas, monitoring and forecasting of air quality parameters have become popular as an important topic in atmospheric and environmental research today. The knowledge on the dynamics and complexity of air pollutants behavior has made artificial intelligence models as a useful tool for a more accurate pollutant concentration prediction. This paper focuses on an innovative method of daily air pollution prediction using combination of Support Vector Machine (SVM) as predictor and Partial Least Square (PLS) as a data selection tool based on the measured values of CO concentrations. The CO concentrations of Rey monitoring station in the south of Tehran, from Jan. 2007 to Feb. 2011, have been used to test the effectiveness of this method. The hourly CO concentrations have been predicted using the SVM and the hybrid PLS-SVM models. Similarly, daily CO concentrations have been predicted based on the aforementioned four years measured data. Results demonstrated that both models have good prediction ability; however the hybrid PLS-SVM has better accuracy. In the analysis presented in this paper, statistic estimators including relative mean errors, root mean squared errors and the mean absolute relative error have been employed to compare performances of the models. It has been concluded that the errors decrease after size reduction and coefficients of determination increase from 56 to 81% for SVM model to 65-85% for hybrid PLS-SVM model respectively. Also it was found that the hybrid PLS-SVM model required lower computational time than SVM model as expected, hence supporting the more accurate and faster prediction ability of hybrid PLS-SVM model.

Cyclic lipopeptide signature as fingerprinting for the screening of halotolerant Bacillus strains towards microbial enhanced oil recovery.

PubMed

Farias, Bárbara C S; Hissa, Denise C; do Nascimento, Camila T M; Oliveira, Samuel A; Zampieri, Davila; Eberlin, Marcos N; Migueleti, Deivid L S; Martins, Luiz F; Sousa, Maíra P; Moyses, Danuza N; Melo, Vânia M M

2018-02-01

Cyclic lipopeptides (CLPs) are non-ribosomal biosurfactants produced by Bacillus species that exhibit outstanding interfacial activity. The synthesis of CLPs is under genetic and environmental influence, and representatives from different families are generally co-produced, generating isoforms that differ in chemical structure and biological activities. This study to evaluate the effect of low and high NaCl concentrations on the composition and surface activity of CLPs produced by Bacillus strains TIM27, TIM49, TIM68, and ICA13 towards microbial enhanced oil recovery (MEOR). The strains were evaluated in mineral medium containing NaCl 2.7, 66, or 100 g L -1 and growth, surface tension and emulsification activity were monitored. Based on the analysis of 16S rDNA, gyrB and rpoB sequences TIM27 and TIM49 were assigned to Bacillus subtilis, TIM68 to Bacillus vallismortis, and ICA13 to Bacillus amyloliquefaciens. All strains tolerated up to 100-g L -1 NaCl, but only TIM49 and TIM68 were able to reduce surface tension at this concentration. TIM49 also showed emulsification activity at concentrations up to 66-g L -1 NaCl. ESI-MS analysis showed that the strains produced a mixture of CLPs, which presented distinct CLP profiles at low and high NaCl concentrations. High NaCl concentration favored the synthesis of surfactins and/or fengycins that correlated with the surface activities of TIM49 and TIM68, whereas low concentration favored the synthesis of iturins. Taken together, these findings suggest that the determination of CLP signatures under the expected condition of oil reservoirs can be useful in the guidance for choosing well-suited strains to MEOR.

17β-estradiol in runoff as affected by various poultry litter application strategies.

PubMed

Delaune, P B; Moore, P A

2013-02-01

Steroidal hormones, which are excreted by all mammalian species, have received increasing attention in recent years due to potential environmental implications. The objective of this study was to evaluate 17β-estradiol concentrations in runoff water from plots receiving poultry litter applications using various management strategies. Treatments included the effects of 1) aluminum sulfate (alum) application rates to poultry litter; 2) time until the first runoff event occurs after poultry litter application; 3) poultry litter application rate; 4) fertilizer type; and 5) litter from birds fed modified diets. Rainfall simulators were used to cause continuous runoff from fertilized plots. Runoff samples were collected and analyzed for 17β-estradiol concentrations. Results showed that increasing alum additions to poultry litter decreased 17β-estradiol concentrations in runoff water. A significant exponential decline in 17β-estradiol runoff was also observed with increasing time until the first runoff event after litter application. Concentrations of 17β-estradiol in runoff water increased with increasing litter application rate and remained above background concentrations after three runoff events at higher application rates. Management practices such as diet modification and selection of fertilizer type were also shown to affect 17β-estradiol concentrations in runoff water. Although results from these experiments typically represented a worst case scenario since runoff events generally occurred immediately after litter application, the contaminant loss from pastures fertilized with poultry litter can be expected to be much lower than continual estradiol loadings observed from waste water treatment plants. Management practices such as alum amendment and application timing can significantly reduce the risk of 17β-estradiol losses in the environment. Copyright © 2012 Elsevier B.V. All rights reserved.

Combined effects of deforestation and doubled atmospheric CO{sub 2} concentrations on the climate of Amazonia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Costa, M.H.; Foley, J.A.

2000-01-01

It is generally expected that the Amazon basin will experience at least two major environmental changes during the next few decades and centuries: (1) increasing areas of forest will be converted to pasture and cropland, and (2) concentrations of atmospheric CO{sub 2} will continue to rise. In this study, the authors use the National Center for Atmospheric Research GENESIS atmospheric general circulation model, coupled to the Integrated Biosphere Simulator, to determine the combined effects of large-scale deforestation and increased CO{sub 2} concentrations (including both physiological and radiative effects) on Amazonian climate. In these simulations, deforestation decreases basin-average precipitation by 0.73more » mm day{sup {minus}1} over the basin, as a consequence of the general reduction in vertical motion above the deforested area (although there are some small regions with increased vertical motion). The overall effect of doubled CO{sub 2} concentrations in Amazonia is an increase in basin-average precipitation of 0.28 mm day{sup {minus}1}. The combined effect of deforestation and doubled CO{sub 2}, including the interactions among the processes, is a decrease in the basin-average precipitation of 0.42 mm day{sup {minus}1}. While the effects of deforestation and increasing CO{sub 2} concentrations on precipitation tend to counteract one another, both processes work to warm the Amazon basin. The effect of deforestation and increasing CO{sub 2} concentrations both tent to increase surface temperature, mainly because of decreases in evapotranspiration and the radiative effect of CO{sub 2}. The combined effect of deforestation and doubled CO{sub 2}, including the interactions among the processes, increases the basin-average temperature by roughly 3.5 C.« less

Rotenone persistence model for montane streams

USGS Publications Warehouse

Brown, Peter J.; Zale, Alexander V.

2012-01-01

The efficient and effective use of rotenone is hindered by its unknown persistence in streams. Environmental conditions degrade rotenone, but current label instructions suggest fortifying the chemical along a stream based on linear distance or travel time rather than environmental conditions. Our objective was to develop models that use measurements of environmental conditions to predict rotenone persistence in streams. Detailed measurements of ultraviolet radiation, water temperature, dissolved oxygen, total dissolved solids (TDS), conductivity, pH, oxidation–reduction potential (ORP), substrate composition, amount of organic matter, channel slope, and travel time were made along stream segments located between rotenone treatment stations and cages containing bioassay fish in six streams. The amount of fine organic matter, biofilm, sand, gravel, cobble, rubble, small boulders, slope, pH, TDS, ORP, light reaching the stream, energy dissipated, discharge, and cumulative travel time were each significantly correlated with fish death. By using logistic regression, measurements of environmental conditions were paired with the responses of bioassay fish to develop a model that predicted the persistence of rotenone toxicity in streams. This model was validated with data from two additional stream treatment reaches. Rotenone persistence was predicted by a model that used travel time, rubble, and ORP. When this model predicts a probability of less than 0.95, those who apply rotenone can expect incomplete eradication and should plan on fortifying rotenone concentrations. The significance of travel time has been previously identified and is currently used to predict rotenone persistence. However, rubble substrate, which may be associated with the degradation of rotenone by adsorption and volatilization in turbulent environments, was not previously considered.

Environmental Risk Assessment of Pharmaceutical Mixtures: Demands, Gaps, and Possible Bridges.

PubMed

Backhaus, Thomas

2016-07-01

The ecotoxicological risk of pharmaceutical mixtures typically exceeds the risk of each individual compound, which calls specific attention to the fact that monitoring surveys routinely find complex pharmaceutical mixtures in various environmental compartments. However, although the body of evidence on the ecotoxicology of pharmaceutical mixtures is quite consistent, the current guidelines for the environmental risk assessment of pharmaceuticals often do not explicitly address mixture effects. Data availability and acceptable methods often limit such assessments. A tiered approach that begins with summing up individual risk quotients, i.e., the ratio between the predicted or measured environmental concentration and the predicted no effect concentration (PNEC) is therefore suggested in this paper, in order to improve the realism of the environmental risk assessment of pharmaceuticals. Additionally, the use of a mixture-specific assessment factor, as well as the classical mixture toxicity concepts of concentration addition and independent action is explored. Finally, specific attention is given to the exposure-based waiving of environmental risk assessments, as currently implemented in screening or pre-screening phases (tier 0 in Europe, categorical exclusion in the USA), since even low, individually non-toxic concentrations might combine to produce substantial mixture effects.

Methods To Characterize Contaminant Residuals After Environmental Dredging

EPA Science Inventory

Environmental dredging is a common remedial action for managing contaminated sediments. However, post dredging contaminant concentrations in surface sediment are difficult to predict prior to initiating dredging actions. In some cases, post surface concentrations have been high...

Lead concentrations and isotope ratios in street dust determined by electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry.

PubMed

Nageotte, S M; Day, J P

1998-01-01

A major source of environmental lead, particularly in urban areas, has been from the combustion of leaded petrol. Street dust has previously been used to assess urban lead contamination, and the dust itself can also be a potential source of lead ingestion, particularly to children. The progressive reduction of lead in petrol, in recent years, would be expected to have been reflected in a reduction of lead in urban dust. We have tested this hypothesis by repeating an earlier survey of Manchester street dust and carrying out a comparable survey in Paris. Samples were collected from streets and parks, lead was extracted by digestion with concentrated nitric acid and determined by electrothermal atomic absorption spectrometry. Lead isotope ratios were measured by inductively coupled plasma mass spectrometry. Results for Manchester show that lead concentrations have fallen by about 40% (street dust averages, 941 micrograms g-1 (ppm) in 1975 down to 569 ppm in 1997). In Paris, the lead levels in street dust are much higher and significant differences were observed between types of street (not seen in Manchester). Additionally, lead levels in parks were much lower than in Manchester. Samples collected under the Eiffel Tower had very high concentrations and lead isotope ratios showed that this was unlikely to be fallout from motor vehicles but could be due to the paint used on the tower. Isotope ratios measurements also revealed that lead additives used in France and the UK come from different sources.

Generalized concentration addition: a method for examining mixtures containing partial agonists.

PubMed

Howard, Gregory J; Webster, Thomas F

2009-08-07

Environmentally relevant toxic exposures often consist of simultaneous exposure to multiple agents. Methods to predict the expected outcome of such combinations are critical both to risk assessment and to an accurate judgment of whether combinations are synergistic or antagonistic. Concentration addition (CA) has commonly been used to assess the presence of synergy or antagonism in combinations of similarly acting chemicals, and to predict effects of combinations of such agents. CA has the advantage of clear graphical interpretation: Curves of constant joint effect (isoboles) must be negatively sloped straight lines if the mixture is concentration additive. However, CA cannot be directly used to assess combinations that include partial agonists, although such agents are of considerable interest. Here, we propose a natural extension of CA to a functional form that may be applied to mixtures including full agonists and partial agonists. This extended definition, for which we suggest the term "generalized concentration addition," encompasses linear isoboles with slopes of any sign. We apply this approach to the simple example of agents with dose-response relationships described by Hill functions with slope parameter n=1. The resulting isoboles are in all cases linear, with negative, zero and positive slopes. Using simple mechanistic models of ligand-receptor systems, we show that the same isobole pattern and joint effects are generated by modeled combinations of full and partial agonists. Special cases include combinations of two full agonists and a full agonist plus a competitive antagonist.

Multivariate analysis of the heterogeneous geochemical processes controlling arsenic enrichment in a shallow groundwater system.

PubMed

Huang, Shuangbing; Liu, Changrong; Wang, Yanxin; Zhan, Hongbin

2014-01-01

The effects of various geochemical processes on arsenic enrichment in a high-arsenic aquifer at Jianghan Plain in Central China were investigated using multivariate models developed from combined adaptive neuro-fuzzy inference system (ANFIS) and multiple linear regression (MLR). The results indicated that the optimum variable group for the AFNIS model consisted of bicarbonate, ammonium, phosphorus, iron, manganese, fluorescence index, pH, and siderite saturation. These data suggest that reductive dissolution of iron/manganese oxides, phosphate-competitive adsorption, pH-dependent desorption, and siderite precipitation could integrally affect arsenic concentration. Analysis of the MLR models indicated that reductive dissolution of iron(III) was primarily responsible for arsenic mobilization in groundwaters with low arsenic concentration. By contrast, for groundwaters with high arsenic concentration (i.e., > 170 μg/L), reductive dissolution of iron oxides approached a dynamic equilibrium. The desorption effects from phosphate-competitive adsorption and the increase in pH exhibited arsenic enrichment superior to that caused by iron(III) reductive dissolution as the groundwater chemistry evolved. The inhibition effect of siderite precipitation on arsenic mobilization was expected to exist in groundwater that was highly saturated with siderite. The results suggest an evolutionary dominance of specific geochemical process over other factors controlling arsenic concentration, which presented a heterogeneous distribution in aquifers. Supplemental materials are available for this article. Go to the publisher's online edition of the Journal of Environmental Science and Health, Part A, to view the supplemental file.

Treatment of reverse-osmosis concentrate of printing and dyeing wastewater by electro-oxidation process with controlled oxidation-reduction potential (ORP).

PubMed

Wang, Jiade; Zhang, Tian; Mei, Yu; Pan, Bingjun

2018-06-01

Reverse osmosis concentrate (ROC) of printing and dyeing wastewater remains as a daunting environmental issue, which is characterized by high salinity, chemical oxygen demand (COD), chroma and low biodegradability. In this study electro-oxidation process (PbO 2 /Ti electrode) coupled with oxidation-reduction potential (ORP) online monitor was applied to treat such a ROC effluent. The results show that with the increase of specific electrical charge (Q sp ), the removal efficiencies of COD, TN and chroma increased significantly at the incipience and then reached a gentle stage; the optimal total current efficiency (12.04 kWh m -3 ) was obtained with the current density of 10 mA cm -2 (Q sp , 3.0 Ah L -1 ). Meanwhile, some inorganic ions can be simultaneously removed to varying degrees. FTIR analyses indicated that the macromolecular organics were decomposed into smaller molecules. A multi-parameter linear relationship between ORP and Q sp , COD and Cl - concentration was established, which can quantitatively reflect the effect of current density, chloride ion concentration, pollutants and reaction time on the performance of the electro-oxidation system. As compared to a traditional constant-current system, the constant-ORP system developed in this study (through the back-propagation neural network [BPN] model with ORP monitoring) approximately reduced the energy cost by 24-29%. The present work is expected to provide a potential alternative in optimizing the electro-oxidation process. Copyright © 2018 Elsevier Ltd. All rights reserved.

A review of the evaluation of TENORM levels at the produced water lagoon of the Minagish oil field using high-resolution gamma-ray spectrometry

NASA Astrophysics Data System (ADS)

Shams, H. M.; Bradley, D. A.; Alshammari, H.; Regan, P. H.

2017-11-01

An evaluation of the specific activity concentrations associated with technologically enhanced naturally occurring radioactive materials (TENORM) and anthropogenic radionuclides has been undertaken as part of a systematic study to provide a radiological map of the outer boundary of the produced water lagoon located in the Minagish oil field in the south west of the State of Kuwait. The lagoon contains material from the discharge of produced water which is a by-product of oil production in the region. The lagoon samples were prepared and placed into sealed, marinelli beakers for a full gamma-ray spectrometric analysis using a high-resolution, low-background, high-purity germanium detection systems at the University of Surrey Environmental Radioactivity Laboratory. Of particular interest are the calculation of the activity concentrations associated with members of the decay chains following decays of the primordial radionuclides of the 238U chain (226Ra, 214Pb, 214Bi) and the 232Th chain (228Ra, 228Ac, 212Pb, 212Bi, 208Tl), and the enhanced concentrations of radium isotopes. This conference paper presents an overview summary of the experimental samples which have been measured and the analysis techniques applied, including isotopic correlation plots across the sample region. The result shows the expected significant increase in 226Ra (and progeny) concentrations compared to the NORM values previously reported by our group for the overall terrain in Kuwait.

Adsorption characteristics of selected pharmaceuticals and an endocrine disrupting compound-Naproxen, carbamazepine and nonylphenol-on activated carbon.

PubMed

Yu, Zirui; Peldszus, Sigrid; Huck, Peter M

2008-06-01

The adsorption of two representative pharmaceutically active compounds (PhACs) (naproxen and carbamazepine) and one endocrine disrupting compound (nonylphenol) were evaluated on two types of activated carbon. When determining their isotherms at environmentally relevant concentration levels, it was found that at this low concentration range (10-800 ng/L), removals of the target compounds were contrary to expectations based on their hydrophobicity. Nonylphenol (log K(ow) 5.8) was most poorly adsorbed, whereas carbamazepine (log K(ow) 2.45) was most adsorbable. Nonylphenol Freundlich isotherms at this very low concentration range had a much higher 1/n compared to isotherms at much higher concentrations. This indicates that extrapolation from an isotherm obtained at a high concentration range to predict the adsorption of nonylphenol at a concentration well below the range of the original isotherm, leads to a substantial overestimation of its removals. Comparison of isotherms for the target compounds to those for other conventional micropollutants suggested that naproxen and carbamazepine could be effectively removed by applying the same dosage utilized to remove odorous compounds (geosmin and MIB) at very low concentrations. The impact of competitive adsorption by background natural organic matter (NOM) on the adsorption of the target compounds was quantified by using the ideal adsorbed solution theory (IAST) in combination with the equivalent background compound (EBC) approach. The fulfilment of the requirements for applying the simplified IAST-EBC model, which leads to the conclusion that the percentage removal of the target compounds at a given carbon dosage is independent of the initial contaminant concentration, was confirmed for the situation examined in the paper. On this basis it is suggested that the estimated minimum carbon usage rates (CURs) to achieve 90% removal of these emerging contaminants would be valid at concentrations of less than 500 ng/L in natural water.

Physical environment and life expectancy at birth in Mexico: an eco-epidemiological study.

PubMed

Idrovo, Alvaro J

2011-06-01

The objective of this ecological study was to ascertain the effects of physical environment on life expectancy at birth, using data from all 32 Mexican states. 50 environmental indicators with information about demography, housing, poverty, water, soils, biodiversity, forestry resources, and residues were included in exploratory factor analysis. Four factors were extracted: population vulnerability/susceptibility, and biodiversity (FC1), urbanization, industrialization, and environmental sustainability (FC2), ecological resilience (FC3), and free-plague environments (FC4). Using OLS regressions, FC2, FC3, and FC4 were found to be positively associated with life expectancy at birth, while FC1 was negatively associated. This study suggests that physical environment is an important macro-determinant of the health of the Mexican population, and highlights the usefulness of ecological concepts in epidemiological studies.

Historical Fluxes of Toxic Trace Elements and Associated Implications in the Salton Sea Basin

NASA Astrophysics Data System (ADS)

Odigie, K. O.; Hardisty, D. S.; Geraci, J. B.; Lyons, T. W.

2017-12-01

The Salton Sea is a polymictic, hypersaline lake that is predominantly sustained by wastewater and agricultural runoff from Mexico and the United States. It is a terminal lake that acts as a net sink for toxicants, which in addition to nutrients and increasing salinity, have dramatically transformed the lake over the past century. However, the impacts of these changes on the cycling and bio-accessibility of toxic elements and compounds and their associated human and environmental health implications are not well understood. This project aims to measure and model the fluxes of toxic elements, including selenium, lead, and mercury, in the lake over temporal and spatial scales by using geochemical data from the analysis of sediment cores, a pervasive salt crust, and the water column. The project also aims to elucidate the bio-accessibility and depositional environments of these elements. Preliminary results highlight two different oxygen concentration regimes in the lake: an increasingly anoxic condition in the bottom of the northern lobe and a seasonally variable oxygen deficiency in the bottom of the southern lobe. The deteriorating conditions at the lake could be exacerbated by a receding shoreline, which has already exposed several square kilometres of lake bed and is expected to continue as future inflows are diverted under the Quantification Settlement Agreement. Continued water conservation by Imperial Valley farmers and the increasing reuse of reclaimed water by Mexico are also expected to contribute to reduced inflows to the lake. Therefore, improved understanding of the cycling of toxic elements and their potential remobilization, including via wind entrainment (dust) associated with lake desiccation, will be valuable in protecting human and environmental health within the Salton Sea basin.

The creation of reasonable projections toward sustainable development considering the climate and socioeconomic changes in the Pacific Islands

NASA Astrophysics Data System (ADS)

Watanabe, S.; Iida, A.; Nakatani, J.; Noda, K.; Take, M.; Nakamura, S.

2015-12-01

The impacts of climate and socioeconomic change in the future are important factors to consider when discussing the issues of sustainable development in the Pacific Islands, since their impacts here are relatively large compared to those in other regions due to the severe limitation of internal resources and the external dependency of the life essentials. The tourism industry is the key driving force behind the economic growth in island region and it is promoted by the environmental attractions. This study constructs scenarios that foresees the effects of these changes and assesses the subsequent impact on both the local community and the tourism industry. In this study, the scenarios have been developed based on the representative concentration pathways (RCPs) and the shared socioeconomic pathways (SSPs). The progress of climate change was expected to affect the attraction of tourists as well as resources availability and food production. The difference of SSPs was expected to affect the quality of life in the local society and the quantity and/or the quality of tourism. A downscale and bias-correction using a local dataset was applied to assess the impacts of climate change, and the relationships between GDP, population, and estimated land availability in the current situation were applied to assess the impact of socioeconomic change. As case studies, the scenarios were constructed to assess the impacts in the Republic of Palau and Ishigaki Island, Japan. Both are typical islands where tourism is the main industry. The situation of environmental resources, local society, and tourism under changing climate and socioeconomic conditions was assessed using these scenarios. The creation of reasonable projections under appropriate scenarios can contribute to sustainable development not only in these islands but also in most Pacific Islands.

Bright spots among the world’s coral reefs

NASA Astrophysics Data System (ADS)

Cinner, Joshua E.; Huchery, Cindy; MacNeil, M. Aaron; Graham, Nicholas A. J.; McClanahan, Tim R.; Maina, Joseph; Maire, Eva; Kittinger, John N.; Hicks, Christina C.; Mora, Camilo; Allison, Edward H.; D'Agata, Stephanie; Hoey, Andrew; Feary, David A.; Crowder, Larry; Williams, Ivor D.; Kulbicki, Michel; Vigliola, Laurent; Wantiez, Laurent; Edgar, Graham; Stuart-Smith, Rick D.; Sandin, Stuart A.; Green, Alison L.; Hardt, Marah J.; Beger, Maria; Friedlander, Alan; Campbell, Stuart J.; Holmes, Katherine E.; Wilson, Shaun K.; Brokovich, Eran; Brooks, Andrew J.; Cruz-Motta, Juan J.; Booth, David J.; Chabanet, Pascale; Gough, Charlie; Tupper, Mark; Ferse, Sebastian C. A.; Sumaila, U. Rashid; Mouillot, David

2016-07-01

Ongoing declines in the structure and function of the world’s coral reefs require novel approaches to sustain these ecosystems and the millions of people who depend on them. A presently unexplored approach that draws on theory and practice in human health and rural development is to systematically identify and learn from the ‘outliers’—places where ecosystems are substantially better (‘bright spots’) or worse (‘dark spots’) than expected, given the environmental conditions and socioeconomic drivers they are exposed to. Here we compile data from more than 2,500 reefs worldwide and develop a Bayesian hierarchical model to generate expectations of how standing stocks of reef fish biomass are related to 18 socioeconomic drivers and environmental conditions. We identify 15 bright spots and 35 dark spots among our global survey of coral reefs, defined as sites that have biomass levels more than two standard deviations from expectations. Importantly, bright spots are not simply comprised of remote areas with low fishing pressure; they include localities where human populations and use of ecosystem resources is high, potentially providing insights into how communities have successfully confronted strong drivers of change. Conversely, dark spots are not necessarily the sites with the lowest absolute biomass and even include some remote, uninhabited locations often considered near pristine. We surveyed local experts about social, institutional, and environmental conditions at these sites to reveal that bright spots are characterized by strong sociocultural institutions such as customary taboos and marine tenure, high levels of local engagement in management, high dependence on marine resources, and beneficial environmental conditions such as deep-water refuges. Alternatively, dark spots are characterized by intensive capture and storage technology and a recent history of environmental shocks. Our results suggest that investments in strengthening fisheries governance, particularly aspects such as participation and property rights, could facilitate innovative conservation actions that help communities defy expectations of global reef degradation.

U. S. EPA’S NA APPROACH FOR PETROLEUM HYDROCARBONS

EPA Science Inventory

Most evaluations of NA of petroleum hydrocarbons use geochemical data to document the NA through biodegradation. The expected trends during biodegradation (plume interior vs. background concentrations) are Dissolved oxygen concentrations below background, Nitrate concentrations ...

National patterns in environmental injustice and inequality: outdoor NO2 air pollution in the United States.

PubMed

Clark, Lara P; Millet, Dylan B; Marshall, Julian D

2014-01-01

We describe spatial patterns in environmental injustice and inequality for residential outdoor nitrogen dioxide (NO2) concentrations in the contiguous United States. Our approach employs Census demographic data and a recently published high-resolution dataset of outdoor NO2 concentrations. Nationally, population-weighted mean NO2 concentrations are 4.6 ppb (38%, p<0.01) higher for nonwhites than for whites. The environmental health implications of that concentration disparity are compelling. For example, we estimate that reducing nonwhites' NO2 concentrations to levels experienced by whites would reduce Ischemic Heart Disease (IHD) mortality by ∼7,000 deaths per year, which is equivalent to 16 million people increasing their physical activity level from inactive (0 hours/week of physical activity) to sufficiently active (>2.5 hours/week of physical activity). Inequality for NO2 concentration is greater than inequality for income (Atkinson Index: 0.11 versus 0.08). Low-income nonwhite young children and elderly people are disproportionately exposed to residential outdoor NO2. Our findings establish a national context for previous work that has documented air pollution environmental injustice and inequality within individual US metropolitan areas and regions. Results given here can aid policy-makers in identifying locations with high environmental injustice and inequality. For example, states with both high injustice and high inequality (top quintile) for outdoor residential NO2 include New York, Michigan, and Wisconsin.

Detection of the actinides and cesium from environmental samples

NASA Astrophysics Data System (ADS)

Snow, Mathew Spencer

Detection of the actinides and cesium in the environment is important for a variety of applications ranging from environmental remediation to safeguards and nuclear forensics. The utilization of multiple different elemental concentrations and isotopic ratios together can significantly improve the ability to attribute contamination to a unique source term and/or generation process; however, the utilization of multiple elemental "signatures" together from environmental samples requires knowledge of the impact of chemical fractionation for various elements under a variety of environmental conditions (including predominantly aqueous versus arid conditions). The research reported in this dissertation focuses on three major areas: 1. Improving the understanding of actinide-mineral interactions at ultra-low concentrations. Chapter 2 reports a batch sorption and modeling study of Np(V) sorption to the mineral goethite from attomolar to micromolar concentrations. 2. Improving the detection capabilities for Thermal Ionization Mass Spectrometry (TIMS) analyses of ultra-trace cesium from environmental samples. Chapter 4 reports a new method which significantly improves the chemical yields, purification, sample processing time, and ultimately, the detection limits for TIMS analyses of femtogram quantities of cesium from a variety of environmental sample matrices. 3. Demonstrating how actinide and cesium concentrations and isotopic ratios from environmental samples can be utilized together to determine a wealth of information including environmental transport mechanisms (e.g. aqueous versus arid transport) and information on the processes which generated the original material. Chapters1, 3 and 5 demonstrate these principles using Pu, Am, Np, and Cs concentrations and isotopic ratios from contaminated soils taken near the Subsurface Disposal Area (SDA) of Idaho National Laboratory (INL) (a low level radioactive waste disposal site in southeastern Idaho).

Degradation of Di(2-Ethylhexyl) Phthalate by a Novel Gordonia alkanivorans Strain YC-RL2.

PubMed

Nahurira, Ruth; Ren, Lei; Song, Jinlong; Jia, Yang; Wang, Junhuan; Fan, Shuanghu; Wang, Haisheng; Yan, Yanchun

2017-03-01

One bacterial strain, YC-RL2, isolated from petroleum-contaminated soil, could utilize environmental hormone Di(2-Ethylhexyl) phthalate (DEHP) as a sole carbon source for growth. Strain YC-RL2 was identified as Gordonia alkanivorans by 16S rRNA gene analysis and Biolog tests. The effects of environmental factors which might affect the degrading process were optimized at 30 °C and pH 8.0. Strain YC-RL2 showed superior halotolerance and could tolerate up to 0-5% NaCl in trace element medium supplemented with DEHP, although the DEHP degradation rates slowed as NaCl concentration increased. It also showed an outstanding performance in a wide range of pH (6.0-11.0). Meanwhile, strain YC-RL2 was able to withstand high concentrations of DEHP (from 100 to 800 mg/L), and the degradation rates were all above 94%. The DEHP intermediates were detected by HPLC-MS, and the degradation pathway was deduced tentatively. DEHP was transformed into phthalic acid (PA) via mono (2-ethylhexyl) phthalate (MEHP), and PA was further utilized for growth via benzoic acid (BA). The enzyme expected to catalyze the hydrolysis of MEHP to PA was identified from strain YC-RL2. Further investigation found that the enzyme could catalyze the transformation of a wide range of monoalkyl phthalates to PA. This study is the first report about species G. alkanivorans which could degrade several kinds of phthalic acid esters (PAEs), and indicates its application potential for bioremediation of PAE-polluted sites.

Amorphous Silica-Promoted Lysine Dimerization: a Thermodynamic Prediction

NASA Astrophysics Data System (ADS)

Kitadai, Norio; Nishiuchi, Kumiko; Nishii, Akari; Fukushi, Keisuke

2018-03-01

It has long been suggested that mineral surfaces played a crucial role in the abiotic polymerization of amino acids that preceded the origin of life. Nevertheless, it remains unclear where the prebiotic process took place on the primitive Earth, because the amino acid-mineral interaction and its dependence on environmental conditions have yet to be understood adequately. Here we examined experimentally the adsorption of L-lysine (Lys) and its dimer (LysLys) on amorphous silica over a wide range of pH, ionic strength, adsorbate concentration, and the solid/water ratio, and determined the reaction stoichiometries and the equilibrium constants based on the extended triple-layer model (ETLM). The retrieved ETLM parameters were then used, in combination with the equilibrium constant for the peptide bond formation in bulk water, to calculate the Lys-LysLys equilibrium in the presence of amorphous silica under various aqueous conditions. Results showed that the silica surface favors Lys dimerization, and the influence varies greatly with changing environmental parameters. At slightly alkaline pH (pH 9) in the presence of a dilute NaCl (1 mM), the thermodynamically attainable LysLys from 0.1 mM Lys reached a concentration around 50 times larger than that calculated without silica. Because of the versatility of the ETLM, which has been applied to describe a wide variety of biomolecule-mineral interactions, future experiments with the reported methodology are expected to provide a significant constraint on the plausible geological settings for the condensation of monomers to polymers, and the subsequent chemical evolution of life.

Ethinyl estradiol and other human pharmaceutical estrogens in the aquatic environment: a review of recent risk assessment data.

PubMed

Laurenson, James P; Bloom, Raanan A; Page, Stephen; Sadrieh, Nakissa

2014-03-01

Interest in pharmaceuticals in the environment has increased substantially in recent years. Several studies in particular have assessed human and ecological risks from human pharmaceutical estrogens, such as 17α-ethinyl estradiol (EE2). Regulatory action also has increased, with the USA and other countries developing rules to address estrogens and other pharmaceuticals in the environment. Accordingly, the Center for Drug Evaluation and Research at the US Food and Drug Administration has conducted a review and analysis of current data on the long-term ecological exposure and effects of EE2 and other estrogens. The results indicate that mean-flow long-term predicted environmental concentrations (PECs) of EE2 in approximately 99% or more of US surface water segments downstream of wastewater treatment plants are lower than a predicted no-effect concentration (PNEC) for aquatic chronic toxicity of 0.1 ng/L. Exceedances are expected to be primarily in localized, effluent-dominated water segments. The median mean-flow PEC is more than two orders of magnitude lower than this PNEC. Similar results exist for other pharmaceutical estrogens. Data also suggest that the contribution of EE2 more broadly to total estrogenic load in the environment from all sources (including other human pharmaceutical estrogens, endogenous estrogens, natural environmental estrogens, and industrial chemicals), while highly uncertain and variable, appears to be relatively low overall. Additional data and a more comprehensive approach for data collection and analysis for estrogenic substances in the environment, especially in effluent-dominated water segments in sensitive environments, would more fully characterize the risks.

N cycling in SPRUCE (Spruce Peatlands Response Under Climatic and Environmental Changes)

EPA Science Inventory

Peatlands located in boreal regions make up a third of global wetland area and are expected to have the highest temperature increases in response to climate change. As climate warms, we expect peat decomposition may accelerate, altering the cycling of nitrogen. Alterations in th...

Willingness to Pay for Environmental Health Risk Reductions When There are Varying Degrees of Life Expectancy: A White Paper (2006)

EPA Pesticide Factsheets

The use of existing value of statistical life (VSL) estimates in benefit-cost analysis relates to relatively short changes in life expectancy. The authors' strategy for addressing this question is to briefly survey the existing economics literature.

Using Satellite-Based Earth Science Data in a Public Health Decision-Support System to Track and Forecast Pollen Events

NASA Astrophysics Data System (ADS)

Hudspeth, W. B.; Budge, A.

2013-12-01

There is widespread recognition within the public health community that ongoing changes in climate are expected to increasingly pose threats to human health. Environmentally induced health risks to populations with respiratory illnesses are a growing concern globally. Of particular concern are dust and smoke events carrying PM2.5 and PM10 particle sizes, ozone, and pollen. There is considerable interest in documenting the precise linkages between changing patterns in the climate and how these shifts impact the prevalence of respiratory illnesses. The establishment of these linkages can drive the development of early warning and forecasting systems to alert health care professionals of impending air-quality events. As a component of a larger NASA-funded project on Integration of Airborne Dust Prediction Systems and Vegetation Phenology to Track Pollen for Asthma Alerts in Public Health Decision Support Systems, the Earth Data Analysis Center (EDAC) at the University of New Mexico, is developing web-based visualization and analysis services for forecasting pollen concentration data. This decision-support system, New Mexico's Environmental Public Health Tracking System (NMEPHTS), funded by the Centers for Disease Control (CDC) Environmental Public Health Tracking Network (EPHTN), aims to improve health awareness and services by linking health effects data with levels and frequency of environmental exposure. The forecast of atmospheric events with high pollen concentrations has employed a modified version of the DREAM (Dust Regional Atmospheric Model, a verified model for atmospheric dust transport modeling. In this application, PREAM (Pollen Regional Atmospheric Model) models pollen emission using a MODIS-derived phenology of Juniperus spp. communities. Model outputs are verified and validated with ground-based records of pollen release timing and quantities. Outputs of the PREAM model are post-processed and archived in EDAC's Geographic Storage, Transformation, and Retrieval Engine (GStore) database. The GStore geospatial services platform provides general purpose web services based upon the REST service model, and is capable of data discovery, access, and publication functions, metadata delivery functions, data transformation, and auto-generated OGC services for those data products that can support those services. These services are in turn ingested by New Mexico's EPHTN where end users in the public health community can then assess environmental-pubic health data associations. Advances in web mapping and related technologies open new doors for data providers and users that can deliver data and information in near-real time. In the public health community these technologies are being used to enhance disease and syndromic surveillance systems, visualize environmentally-related events such as pollen and dust events, and to provide focused mapping and analysis capabilities on the desktop. Here we present the current results of the project, and will focus on the challenges encountered in providing reliable and accurate forecast of pollen concentrations, as well as the experience of integrating output results and services into end user applications that can provide timely and meaningful alerts and forecasts.

Graphene-enhanced plasmonic nanohole arrays for environmental sensing in aqueous samples

PubMed Central

Genslein, Christa; Hausler, Peter; Kirchner, Eva-Maria; Bierl, Rudolf; Baeumner, Antje J

2016-01-01

The label-free nature of surface plasmon resonance techniques (SPR) enables a fast, specific, and sensitive analysis of molecular interactions. However, detection of highly diluted concentrations and small molecules is still challenging. It is shown here that in contrast to continuous gold films, gold nanohole arrays can significantly improve the performance of SPR devices in angle-dependent measurement mode, as a signal amplification arises from localized surface plasmons at the nanostructures. This leads consequently to an increased sensing capability of molecules bound to the nanohole array surface. Furthermore, a reduced graphene oxide (rGO) sensor surface was layered over the nanohole array. Reduced graphene oxide is a 2D nanomaterial consisting of sp2-hybridized carbon atoms and is an attractive receptor surface for SPR as it omits any bulk phase and therefore allows fast response times. In fact, it was found that nanohole arrays demonstrated a higher shift in the resonance angle of 250–380% compared to a continuous gold film. At the same time the nanohole array structure as characterized by its diameter-to-periodicity ratio had minimal influence on the binding capacity of the sensor surface. As a simple and environmentally highly relevant model, binding of the plasticizer diethyl phthalate (DEP) via π-stacking was monitored on the rGO gold nanohole array realizing a limit of detection of as low as 20 nM. The concentration-dependent signal change was studied with the best performing rGO-modified nanohole arrays. Compared to continuous gold films a diameter-to-periodicity ratio (D/P) of 0.43 lead to a 12-fold signal enhancement. Finally, the effect of environmental waters on the sensor was evaluated using samples from sea, lake and river waters spiked with analytically relevant amounts of DEP during which significant changes in the SPR signal are observed. It is expected that this concept can be successfully transferred to enhance the sensitivity in SPR sensors. PMID:28144507

Macrocyclic fragrance materials--a screening-level environmental assessment using chemical categorization.

PubMed

Salvito, Daniel; Lapczynski, Aurelia; Sachse-Vasquez, Christen; McIntosh, Colin; Calow, Peter; Greim, Helmut; Escher, Beate

2011-09-01

A screening-level aquatic environmental risk assessment for macrocyclic fragrance materials using a "group approach" is presented using data for 30 macrocyclic fragrance ingredients. In this group approach, conservative estimates of environmental exposure and ecotoxicological effects thresholds for compounds within two subgroups (15 macrocyclic ketones and 15 macrocyclic lactones/lactides) were used to estimate the aquatic ecological risk potential for these subgroups. It is reasonable to separate these fragrance materials into the two subgroups based on the likely metabolic pathway required for biodegradation and on expected different ecotoxicological modes of action. The current volumes of use for the macrocyclic ketones in both Europe and North America ranges from <1 (low kg quantities) to no greater than 50 metric tonnes in either region and for macrocyclic lactones/lactides the volume of use range for both regions is <1 to no greater than 1000 metric tonnes in any one region. Based on these regional tonnages, biodegradability of these two subgroups of materials, and minimal in stream dilution (3:1), the conservatively predicted exposure concentrations for macrocyclic ketones would range from <0.01 to 0.05 μg/L in Europe and from <0.01 to 0.03 μg/L in North America. For macrocyclic lactones/lactides, the concentration within the mixing zone would range from <0.01 to 0.7 μg/L in Europe and from <0.01 to 1.0 μg/L in North America. The PNECs derived for the macrocyclic ketones is 0.22 μg/L and for macrocyclic lactones/lactides is 2.7 μg/L. The results of this screening-level aquatic ecological risk assessment indicate that at their current tonnage, often referred to as volumes of use, macrocyclic fragrance materials in Europe and North America, pose a negligible risk to aquatic biota; with no PEC/PNEC ratio exceeding 1 for any material in any subgroup. Copyright © 2011 Elsevier Inc. All rights reserved.

Investigating the link between fish community structure and environmental state in deep-time

NASA Astrophysics Data System (ADS)

Sibert, E. C.

2017-12-01

In the modern ocean, a bottom-up ecological viewpoint posits that the composition of plankton communities is often a function of ambient oceanographic conditions, including nutrient concentrations and water temperature. Thus, certain plankton species or communities can be associated with specific oceanographic conditions, giving them potential as carriers of paleoceanographic information. Furthermore, consumer groups, such as fish, depend on the structure and composition of these plankton, and therefore different plankton communities will support different types of fish. In addition, fish have their own physiological constraints for surviving in particular environments, such as oxygen demand, and metabolic rate, causing certain clades to be selectively associated with different water mass characteristics. Thus, the relative or absolute abundances of different fish species or groups could shed light on shifting oxygen concentrations, temperature, or primary productivity in the past. To assess whether fish communities have sufficient environmental control to provide paleoceanographic insights, I use a variety of morphological, phylogenetic, and ecological statistical approaches, to correlate modern fish communities from around the world with environmental variables. I then apply these principles to a series of ichthyolith assemblages from the Cretaceous and Cenozoic, across both space and time, to assess whether fish community composition, abundance, or other characteristics can be predictive of ocean temperature or export productivity. I find that while the abundance of fish fossils in deep-sea cores is often, though not always, correlated with certain export production and temperature proxies, community composition appears to vary independently of these variables on long timescales, driven more by evolutionary processes. However, there are distinct differences in contemporary communities in different locations, suggesting that there is potential in using fish community composition in well-constrained systems. Furthermore, when fish community structure or abundance diverges from the expected state, this may provide significant insight into the structure and functioning of marine ecosystems.

THE USE AND LIMITATIONS OF DETECTION AND QUANTITATION LIMITS IN ENVIRONMENTAL ANALYSIS

EPA Science Inventory

Site assessment, remediation and compliance monitoring require the routine determination of the concentration of regulated substances in environmental samples. Each measurement methodology providing the concentration determinations, is required to specify key data quality elemen...

Simulating the effect of fire on the ARS Reynolds Creek Experimental Watershed

USDA-ARS?s Scientific Manuscript database

The Conservation Effects Assessment Project (CEAP)-Grazing lands national assessment is designed to quantify the environmental effects of conservation practices on U.S. non-Federal grazing lands. The assessment includes science-based estimates of expected environmental effects of installed conservat...

INDOOR ENVIRONMENTAL DETERMINANTS OF LUNG FUNCTION IN CHILDREN

EPA Science Inventory

Using pulmonary function and family respiratory questionnaire data for 16,689 white children 6 to 13 yr of age from 7 geographic areas, the investigators examined the effect of several environmental and other factors on performance in a standard test of breathing. As expected, FE...

Newspaper Construction of a Moral Farmer

ERIC Educational Resources Information Center

Reisner, Ann

2003-01-01

This study examines how six national newspapers balanced supporting agriculture (a morally good occupation) with supporting environmentalism (nature as a moral value), in an area in which agricultural and environmental interests conflict--farm use of pesticides. The study showed that, contrary to expectations, newspapers supported social change…

75 FR 18551 - Information Collection Activities: Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-12

... telecommunications device for the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 1-800-877-8339... Collection: Antarctic emergency response plan and environmental protection information. OMB Approval Number... environmental protection obligations under the Antarctic Conservation Act. Expected Respondents. Respondents may...

Long-Term Changes of Tropospheric Trace Gases over Pakistan Derived From Multiple Satellite Instruments

NASA Astrophysics Data System (ADS)

Zeb, Naila; Fahim Khokhar, Muhammad; Murtaza, Rabbia; Noreen, Asma; Khalid, Tameem

2016-07-01

Air pollution is the expected key environmental issue of Pakistan in coming years due to its ongoing rapid economic growth and this trend suggests only worst air quality over time. In 2014, World bank reported the Pakistan's urban air quality among the most severe in the world and intimated the government to make improvement in air quality as a priority policy agenda. In addition it is recommended to strengthen the institutional and technical capacity of organizations responsible for air quality management. Therefore, the study is designed to put efforts in highlighting air quality issues. The study will provide first database for tropospheric trace gases over Pakistan. The study aims to analyse tropospheric concentrations of CO, TOC, NO2 and HCHO over Pakistan using multisensory data from January 2005 to January 2014. Spatio-temporal and seasonal variability of tropospheric trace gases is observed over the decade to explore long term trend. Hotspots are identified to see variation of species with latitude and to highlight possible sources of trace gases over the Pakistan. High concentrations of trace gases are mainly observed over the Punjab region, which may be attributed to its metropolitan importance. It is the major agricultural, industrialized and urbanized (nearly 60% of the Pakistan's population) sector of the country. Overall significant decreasing trend of CO is identified by MOPITT with relative change of 12.4%. Tropospheric ozone column (TOC) showed insignificant increasing trend with temporal increase of 10.4% whereas NO2 exhibited a significant temporal increase of about 28%. For formaldehyde (HCHO), an increase of about 3.8% is calculated for SCIAMACHY data. Well defined seasonal cycles for these trace gases are observed over the whole study period. CO concentrations showed peak in winter months (November/December/January/February) and dip in the months of Summer/Monsoon (June/July/August). In spite of CO, TCO increases gradually in March and peaks in June (Summer/Monsoon). For NO2, the highest concentrations are observed during Winter and the lowest concentrations are found in Summer/Monsoon. Like TOC, the HCHO showed seasonal maxima during summer and minima during winter. The expected sources are the crop residue burning, biomass/fossil fuel burning for heating purposes, urbanization, industrialization and meterological variations. Further focus is made on exploring the association of trace gases in atmosphere and their source identification.

Multimedia modeling of engineered nanoparticles with SimpleBox4nano: model definition and evaluation.

PubMed

Meesters, Johannes A J; Koelmans, Albert A; Quik, Joris T K; Hendriks, A Jan; van de Meent, Dik

2014-05-20

Screening level models for environmental assessment of engineered nanoparticles (ENP) are not generally available. Here, we present SimpleBox4Nano (SB4N) as the first model of this type, assess its validity, and evaluate it by comparisons with a known material flow model. SB4N expresses ENP transport and concentrations in and across air, rain, surface waters, soil, and sediment, accounting for nanospecific processes such as aggregation, attachment, and dissolution. The model solves simultaneous mass balance equations (MBE) using simple matrix algebra. The MBEs link all concentrations and transfer processes using first-order rate constants for all processes known to be relevant for ENPs. The first-order rate constants are obtained from the literature. The output of SB4N is mass concentrations of ENPs as free dispersive species, heteroaggregates with natural colloids, and larger natural particles in each compartment in time and at steady state. Known scenario studies for Switzerland were used to demonstrate the impact of the transport processes included in SB4N on the prediction of environmental concentrations. We argue that SB4N-predicted environmental concentrations are useful as background concentrations in environmental risk assessment.

Maywood Interim Storage Site: Annual environmental report for calendar year 1990, Maywood, New Jersey

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-09-01

Environmental monitoring of the US Department of Energy's (DOE) Maywood Interim Storage Site (MISS) and surrounding area began in 1984. MISS is part of the Formerly Utilized Sites Remedial Action Program (FUSRAP), a DOE program to decontaminate or otherwise control sites where residual radioactive materials remain from the early years of the nation's atomic energy program or from commercial operations causing conditions that Congress has authorized DOE to remedy. The MISS Environmental monitoring programs was established to accommodate facility characteristics, applicable regulations, hazard potential, quantities and concentrations of materials released, extent and use of affected land and water, and localmore » public interest or concern. The environmental monitoring program at MISS includes sampling networks for radon concentrations in air; external gamma radiation exposure; and total uranium, radium-226, and thorium-232 concentrations in surface water, sediment, and groundwater. Additionally, several nonradiological parameters are measured in surface water, sediment, and groundwater. Monitoring results are compared with applicable Environmental Protection Agency (EPA) standards; federal, state, and local applicable or relevant and appropriate requirements (ARARs); and/or DOE derived concentration guidelines (DCGs). Environmental standards, ARARs, and DCGs are established to protect public health and the environment. Results from the 1990 environmental monitoring program show that concentrations of the contaminants of concern were all below applicable standards. Because the site is used only for interim storage and produces no processing effluents, all monitoring, except for radon and direct gamma radiation, was done on a quarterly basis. 18 refs., 17 figs., 28 tabs.« less

Environmental risk assessment of pharmaceutical drug substances--conceptual considerations.

PubMed

Länge, Reinhard; Dietrich, Daniel

2002-05-10

Drugs, i.e. active ingredients of human medicinal products, may be introduced into the environment after use in patients by sewage effluent pathways and consequently are detected at low concentrations in sewage effluents and in surface waters. Legal requirements in a number of geographical regions (Europe, US, and intended in Canada) demand environmental risk assessments (ERA) for new drug substances. Existing regulatory concepts of ERA are based initially on a set of short-term ecotoxicological studies in three to four different species, environmental behavior and the application of assessment factors to correct for the ERA inherent uncertainty. Based on theoretical considerations and the experience with a very limited, but well investigated, number of examples while considering that drugs are highly biologically active compounds, the appropriateness of this risk assessment procedure for all drug substances might be questioned. Indeed, e.g. long-term effects may occur at much lower concentrations and follow different toxicodynamic mechanism than extrapolated from short-term studies., In such cases, the application of assessment factors for deriving chronic no-observed effect concentration (NOECs) appears to be problematic. Although long-term tests with a variety of organisms would provide a complete database for the evaluation of the environmental risks, this is unachievable for all drugs due to time, money and animal welfare constraints. In order to avoid unnecessary testing, a concept is presented, which makes use of pharmacological and toxicological, as well as pharmaco- and toxicokinetic information derived from mammals during drug substance development. Useful data for adoption in a case-by-case testing strategy can be obtained by evaluating (a) the pharmacological activity, which indicates specific targets in mammalian species and may allow for an analysis, whether a similar target is available in aquatic species; (b) the mammalian toxicity, which may indicate, which targets are most susceptible to adverse effects; (c) the difference between acute and chronic effects in mammals, since the magnitude of this difference may indicate, whether long-term effects are expected at significantly lower levels than acute effects; (d) the (pharmacologically and toxicologically) effective plasma levels in mammalian test organisms, which may be compared with the relevant exposure scenario for the environment. Additionally, activity classes of compounds may be established based on experience with specific substances, in order to develop an appropriate test strategy. The above preliminary considerations should support decisions on the selection of candidate substances for chronic effects studies and for the appropriate selection of test species and endpoints to monitor. Generally, ecologically relevant endpoints such as impairment of growth, development and reproduction should be used to assess the ecotoxicologic effects.

Forecasting the effects of EU policy measures on the nitrate pollution of groundwater based on a coupled agroeconomic - hydro(geo)logic model (Invited)

NASA Astrophysics Data System (ADS)

Wendland, F.

2010-12-01

The fundamental objectives of the European Union-Water Framework Directive and the EU Groundwater Directive are to attain a good status of water and groundwater resources in the member states of the EU by 2015. For river basins, whose good status cannot be guaranteed by 2015, catchment wide operational plans and measurement programs have to be drafted and implemented until 2009. In the river basin district Weser, Germany, which comprises a catchment area of ca. 49.000 km2, the achievement of the good status is unclear, or rather unlikely for 63% of the groundwater bodies. Inputs from diffuse sources and most of all nitrate losses from agriculturally used land have been identified as the main reasons for exceeding the groundwater threshold value for nitrate (50 mg/l) and for failing the good qualitative status of groundwater. The achievement of good qualitative status of groundwater bodies entails a particular challenge as the complex ecological, hydrological, hydrogeological and agro-economic relationships have to be considered simultaneously. We used an interdisciplinary model network to predict the nitrogen intakes into groundwater at the regional scale using an area differentiated approach. The model system combines the agro-economic model RAUMIS for estimating nitrogen surpluses from agriculture and the hydrological models GROWA/DENUZ/WEKU for describing the reactive nitrate transport in the soil-groundwater system. In a first step the model is used to analyze the present situation using N surpluses from agriculture for the year 2003. In many region of the Weser basin, particularly in the northwestern part which is characterized by high livestock densities, predicted nitrate concentrations in percolation water exceed the EU groundwater quality standard of 50 mg/L by far. In a second step the temporal and spatial impacts of the common agricultural policy (CAP) of the EU, already implemented agri-environmental measures of the Federal States and the expected developments of agriculture were assessed with regard to both, groundwater quality in 2015 and the regional agricultural income. On average for the whole Weser basin, the reduction of nitrogen surpluses for agricultural areas leads to a decrease of nitrate concentrations in the leachate by about 10 mg NO3/L. In the agricultural intensive used regions much higher reductions in the order of 40 mg NO3/L may be expected. Using the environmental target value for groundwater, i.e. a concentration of 50 mg NO3/L in the leachate as a target for groundwater protection, the model results were used directly to identify those regions where additional agro-environmental reduction measures are required. There, a backward calculation allows the quantification of maximal permissible nitrogen surplus levels, which was used as a reference for the derivation of additional nitrogen reduction measures. It could be shown that a further reduction by ca. 20.000 t N/a (19%) is necessary to reach a nitrate concentration in groundwater of 50 mg/l. The related costs sum up to ca. 75 Mio €/a. The research work was carried out in the framework of the AGRUM Weser project which was funded on behalf of the German Federal Ministry of Food, Agriculture and Consumer protection (BMELV) and the River Basin Commission Weser (FGG).

Collaborative environmental projects in a multicultural society: working from within separate or mutual landscapes?

NASA Astrophysics Data System (ADS)

Tal, Tali; Alkaher, Iris

2010-06-01

A multicultural socio-environmental project that is framed in the ideas of education for sustainability brought together Jew and Arab students was investigated to identify the participants' views of the program's objectives and their accomplishments. We investigated the project's strengths and weaknesses according to the participants' views and the way culturally diverse students addressed the main local socio-environmental conflict related to conservation versus development of a local creek. The participants agreed that the environmental objectives were properly attained, while the social objectives were accomplished to a limited extent. All the participants emphasized the importance of multicultural knowledge and expected to learn and work together. We found different views of the Jewish and the Arab participants regarding expectations, collaboration and overall satisfaction, with higher expectations of the Arab students and leaders. The students' views of the local conflict varied but were not associated with their ethnic background. We suggest that the differences between the groups result from the different positions and needs of each community, and mainly as a consequence of the difficulties that the Arab minority faces in Israel. Overall, we found that the project allowed the expression of multiple voices of both groups, and suggested an applicable program for education for sustainability in a multicultural society. [InlineMediaObject not available: see fulltext.][InlineMediaObject not available: see fulltext.

Nanotube Dispersions Made With Charged Surfactant

NASA Technical Reports Server (NTRS)

Kuper, Cynthia; Kuzma, Mike

2006-01-01

Dispersions (including monodispersions) of nanotubes in water at relatively high concentrations have been formulated as prototypes of reagents for use in making fibers, films, and membranes based on single-walled carbon nanotubes (SWNTs). Other than water, the ingredients of a dispersion of this type include one or more charged surfactant(s) and carbon nanotubes derived from the HiPco(TradeMark) (or equivalent) process. Among reagents known to be made from HiPco(TradeMark)(or equivalent) SWNTs, these are the most concentrated and are expected to be usable in processing of bulk structures and materials. Test data indicate that small bundles of SWNTs and single SWNTs at concentrations up to 1.1 weight percent have been present in water plus surfactant. This development is expected to contribute to the growth of an industry based on applied carbon nanotechnology. There are expected to be commercial applications in aerospace, avionics, sporting goods, automotive products, biotechnology, and medicine.

USEPA QUALITY ASSURANCE AUDITOR IS SCHEDULED FOR A VISIT. WHAT CAN I EXPECT?

EPA Science Inventory

Environmental studies involving data collection activities conducted by or for the United States Environmental Protection Agency (USEPA) are required to undergo a review of their data collection activities. his review is usually in the form of an independent quality assurance (QA...

The Role of Scientific Studies in Building Consensus in Environmental Decision Making: a Coral Reef Example

EPA Science Inventory

We present a new approach for characterizing the potential of scientific studies to reduce conflict among stakeholders in an analytic-deliberative environmental decision-making process. The approach computes a normalized metric, the Expected Consensus Index of New Research (ECINR...

Analysis of the Environmental Impact on Remanufacturing Wind Turbines

NASA Astrophysics Data System (ADS)

Sosa Skrainka, Manuel R.

To deliver clean energy the use of wind turbines is essential. In June 2011 there was an installed wind capacity equivalent to 211,000MW world-wide (WWEA, 2011). By the end of the year 2009 the U.S. had 35,100MW of wind energy installed capacity to generate electricity (AWEA, 2010). This industry has grown in recent years and is expected to grow even more in the future. The environmental impacts that will arise from the increased number of wind turbines and their end-of-life should be addressed, as large amounts of resources will be required to satisfy the current and future market demands for wind turbines. Since future 10MW wind turbines are expected to be as heavy as 1000 tons each, the study of the environmental response of profitable retirement strategies, such as remanufacturing for these machines, must be considered. Because of the increased number of wind turbines and the materials used, this study provides a comparison between the environmental impacts from remanufacturing the components installed inside the nacelle of multi-megawatt wind turbines and wind turbines manufactured using new components. The study methodology is the following: • Describe the life-cycle and the materials and processes employed for the manufacture and remanufacturing for components inside the nacelle. • Identify remanufacturing alternatives for the components inside the nacelle at the end of the expected life-time service of wind turbines. • Evaluate the environmental impacts from the remanufactured components and compare the results with the impacts of the manufacturing of new components using SimaPro. • Conduct sensitivity analysis over the critical parameters of the life cycle assessment • Propose the most environmentally friendly options for the retirement of each major component of wind turbines. After an analysis of the scenarios the goal of the study is to evaluate remanufacturing as an end-of-life option from an environmental perspective for commercial multi-megawatt wind turbines targeted for secondary wind turbine markets.

Microchip Capillary Electrophoresis with Electrochemical Detection for Monitoring Environmental Pollutants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Gang; Lin, Yuehe; Wang, Joseph

2006-01-15

This invited paper reviews recent advances and the key strategies in microchip capillary electrophoresis (CE) with electrochemical detection (ECD) for separating and detecting a variety of environmental pollutants. The subjects covered include the fabrication of microfluidic chips, sample pretreatments, ECD, typical applications of microchip CE with ECD in environmental analysis, and future prospects. It is expected that microchip CE-ECD will become a powerful tool in the environmental field and will lead to the creation of truly portable devices.

NASA Space Shuttle Program: Shuttle Environmental Assurance (SEA) Initiative

NASA Technical Reports Server (NTRS)

Glover, Steve E.; McCool, Alex (Technical Monitor)

2002-01-01

The first Space Shuttle flight was in 1981 and the fleet was originally expected to be replaced with a new generation vehicle in the early 21st century. Space Shuttle Program (SSP) elements proactively address environmental and obsolescence concerns and continue to improve safety and supportability. The SSP manager created the Shuttle Environmental Assurance (SEA) Initiative in 2000. SEA is to provide an integrated approach for the SSP to promote environmental excellence, proactively manage materials obsolescence, and optimize associated resources.

Extreme weather conditions reduce the CO2 fertilization effect in temperate C3 grasslands

NASA Astrophysics Data System (ADS)

Obermeier, Wolfgang; Lehnert, Lukas; Kammann, Claudia; Müller, Christoph; Grünhage, Ludger; Luterbacher, Jürg; Erbs, Martin; Yuan, Naiming; Bendix, Jörg

2016-04-01

The increase in atmospheric greenhouse gas concentrations from anthropogenic activities is the major driver of global climate change. The rising atmospheric carbon dioxide (CO2) concentrations may stimulate plant photosynthesis and, thus, cause a net sink effect in the global carbon cycle. As a consequence of an enhanced photosynthesis, an increase in the net primary productivity (NPP) of C3 plants (termed CO2 fertilization) is widely assumed. This process is associated with a reduced stomatal conductance of leaves as the carbon demand of photosynthesis is met earlier. This causes a higher water-use efficiency and, hence, may reduce water stress in plants exposed to elevated CO2 concentrations ([eCO2]). However, the magnitude and persistence of the CO2 fertilization effect under a future climate including more frequent weather extremes are controversial. To test the CO2 fertilization effect for Central European grasslands, a data set comprising 16 years of biomass samples and environmental variables such as local weather and soil conditions was analysed by means of a novel approach. The data set was recorded on a "Free Air Carbon dioxide Enrichment" (FACE) experimental site which allows to quantify the CO2 fertilization effect under naturally occurring climate variations. The results indicate that the CO2 fertilization effect on the aboveground biomass is strongest under local average environmental conditions. Such intermediate regimes were defined by the mean +/- 1 standard deviation of the long-term average in the respective variable three months before harvest. The observed CO2 fertilization effect was reduced or vanished under drier, wetter and hotter conditions when the respective variable exceeded the bounds of the intermediate regimes. Comparable conditions, characterized by a higher frequency of more extreme weather conditions, are predicted for the future by climate projections. Consequently, biogeochemical models may overestimate the future NPP sink capacity of temperate C3 grasslands. Because temperate grasslands represent an important part of the Earth's terrestrial surface and therefore the global carbon cycle, atmospheric CO2 concentrations [CO2] might increase faster than currently expected.

CELiS (Compact Eyesafe Lidar System), a portable 1.5 μm elastic lidar system for rapid aerosol concentration measurement: Part 1, Instrument Design and Operation

NASA Astrophysics Data System (ADS)

Bird, A. W.; Wojcik, M.; Moore, K. D.; Lemon, R.

2014-12-01

CELiS (Compact Eyesafe Lidar System) is an elastic lidar system conceived for the purpose of monitoring air quality environmental compliance regarding particulate matter (PM) generated from off-road use of wheeled and tracked vehicles. CELiS is a prototype instrument development by the Space Dynamics Laboratory to demonstrate a small, low power, eye-safe lidar system capable of monitoring PM fence-line concentration of fugitive dust from off-road vehicle activity as part of the SERDP (Strategic Environmental Research and Development Program) Measurement and Modeling of Fugitive Dust Emission from Off-Road Department of Defense Activities program. CELiS is small, lightweight and easily transportable for quick setup and measurement of PM concentration and emissions. The instrument is mounted on Moog Quickset pan and tilt positioner. Ground support equipment includes portable racks with laser power and cooler, power supplies, readout electronics and computer. The complete CELiS instrument weighs less than 300 lbs., is less than 1 cubic meters in volume and uses 700 W of 120V AC power. CELiS has a working range of better than 6km and a range resolution of 1.5m-6m. CELiS operates in a biaxial configuration at the 1.5μm eyesafe wavelength. The receiver is an off-axis parabolic (OAP) telescope, aft-optics and alignment assembly and InGaAs APD detector readout. The transmitter is a 20Hz PRF - 25mJ Quantel 1.574 μm laser with a 20x beam expander. Both the receiver and transmitter are mounted on a carbon fiber optical breadboard with a custom mounting solution to minimize misalignment due to thermal operating range (0-40 C) and pointing vectors. Any lidar system used to monitor fence-line PM emissions related to off-road training activities will be subject to a strict eye-safety requirement to protect both troops and wildlife. CELiS is eyesafe at the output aperture. CELiS has participated in two Dugway Proving Ground Lidar exercises performing within expectations. Retrieval of particulate matter concentration is presented in companion poster by K. Moore.

Differential accumulation of polychlorinated biphenyl congeners in the terrestrial food web of the Kalamazoo River Superfund site, Michigan.

PubMed

Blankenship, Alan L; Zwiernik, Matthew J; Coady, Katherine K; Kay, Denise P; Newsted, John L; Strause, Karl; Park, Cyrus; Bradley, Patrick W; Neigh, Arianne M; Millsap, Stephanie D; Jones, Paul D; Giesy, John P

2005-08-15

A series of field studies was conducted to determine the bioaccumulation of polychlorinated biphenyl (PCB) congeners in the terrestrial food web of the Kalamazoo River flood plain. Samples included colocated soils, native plants likely to be consumed by wildlife, several taxa of terrestrial invertebrates, small mammals, passerine bird eggs, nestlings, and adults, and great horned owl plasma and eggs. Mean concentrations of total PCBs in samples from the former Trowbridge impoundment were 6.5 mg/kg dry weight for soils and 0.023, 0.13, 1.3, 1.3, 1.6, and 8.2 mg/kg wet weight for plants, small herbivorous mammals, depurated earthworms, shrews, great horned owl eggs, and house wren eggs, respectively. Historical data from the Kalamazoo River have reported Aroclor-equivalent total PCB concentrations in the terrestrial food web; however, the degree of environmental weathering of the parent PCB mixtures was unknown. In this study, earthworms and composite samples of coleoptera exhibited PCB congener patterns that were similar to patterns in colocated soils. However, in plants, less chlorinated PCBs (e.g., mono-, di-, tri-, and tetrachlorinated biphenyls) were predominant, and in small mammals, there was a notable enrichment of PCBs 153, 180, 138, 118, and 99. In general, concentrations of PCBs were lower in most biota than in soil from the Kalamazoo River Area of Concern (KRAOC) although there was a modest biomagnification of PCBs from lower trophic level biota to highertrophic levels. As a consequence of environmental weathering of PCBs in the terrestrial food web of the KRAOC, the relative potency of the PCBs (expressed as mg TEQs/kg PCBs) decreased from soil to most biota. While there was a general trend, as expected, in which concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) increased with total PCBs, this relationship was rather poor (R2 = 0.13). Taken together, these data suggest that the differential accumulation of PCB congeners in the terrestrial food web can be explained by congener-specific differences in bioavailability from soil, exposure pathways, and metabolic potential of each of the food web components.

Screening and human health risk assessment of pharmaceuticals and their transformation products in Dutch surface waters and drinking water.

PubMed

de Jongh, Cindy M; Kooij, Pascal J F; de Voogt, Pim; ter Laak, Thomas L

2012-06-15

Numerous studies describe the presence of pharmaceuticals in the water cycle, while their transformation products are usually not included. In the current study 17 common pharmaceuticals and 9 transformation products were monitored in the Dutch waters, including surface waters, pre-treated surface waters, river bank filtrates, two groundwater samples affected by surface water and drinking waters. In these samples, 12 pharmaceuticals and 7 transformation products were present. Concentrations were generally highest in surface waters, intermediate in treated surface waters and river bank filtrates and lowest or not detected in produced drinking water. However, the concentrations of phenazone and its environmental transformation product AMPH were significantly higher in river bank filtrates, which is likely due to historical contamination. Fairly constant ratios were observed between concentrations of transformation products and parent pharmaceuticals. This might enable prediction of concentrations of transformation products from concentrations of parent pharmaceuticals. The toxicological relevance of the observed pharmaceuticals and transformation products was assessed by deriving (i) a substance specific provisional guideline value (pGLV) and (ii) a group pGLV for groups of related compounds were under the assumption of additivity of effects within each group. A substantial margin exists between the maximum summed concentrations of these compounds present in different water types and the derived (group) pGLVs. Based on the results of this limited screening campaign no adverse health effects of the studied compounds are expected in (sources of) drinking water in the Netherlands. The presence of transformation products with similar pharmacological activities and concentration levels as their parents illustrates the relevance of monitoring transformation products, and including these in risk assessment. More thorough monitoring yielding information on statistical uncertainty and variability in time and space, and research on possible synergistic effects of low concentration mixtures of compounds belonging to similar pharmacological classes require attention. Copyright © 2012 Elsevier B.V. All rights reserved.

Agricultural Chemical Concentrations and Loads in Rivers Draining the Central Valley, California, to the San Francisco Bay-Delta Estuary: Before and During an Extended Drought

NASA Astrophysics Data System (ADS)

Domagalski, J. L.

2016-12-01

Drought or near drought conditions have occurred in California since 2012. Although some parts of the State received near normal precipitation in water year 2016, other locations were still below average. Extended drought can impact aquatic organisms in a variety of ways because of decreased flows and elevated water temperature. However, lower precipitation and availability of irrigation water may limit subsequent runoff, resulting in reduced concentrations and loads of certain environmental toxicants, such as pesticides and ammonia, thereby limiting their toxic effects. In this study, funded by the U.S. Geological Survey National Water Quality Program, the occurrence of 227 pesticides and degradation products, and nutrients was assessed before and during this current drought in the two largest rivers draining to the San Francisco Bay: the Sacramento and San Joaquin Rivers. The watersheds of both rivers include substantial agricultural and urban land use. Herbicides, insecticides, fungicides, and ammonia were detected throughout the study (2010 to 2016) and models of daily concentration using the seasonal wave model (rloadest) were formulated to assess the amount of time that concentrations may have exceeded benchmark levels known to be toxic to aquatic organisms. Frequently detected pesticides included the fungicide azoxystrobin, herbicides or their degradation products such as diuron, glyphosate, and metolachlor, and insecticides such as imidacloprid. Compounds that are transported primarily by surface runoff generally showed decreasing concentrations as the drought progressed, especially in the San Joaquin River. Compounds mainly transported by groundwater, as indicated by seasonal concentration profiles, had more stable concentrations in the rivers. Mass loads to the Bay all decreased, as expected, because of the lower river discharge. When compared to aquatic-life benchmarks, modeled concentrations indicated that individual compounds were not contributing to toxicity to zooplankton, non-vascular plants, or fish at these two locations where most of the fresh water inputs to this estuary occurs.

Online solid phase extraction liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS) method for the determination of sucralose in reclaimed and drinking waters and its photo degradation in natural waters from South Florida

PubMed Central

2013-01-01

Background Sucralose has gained popularity as a low calorie artificial sweetener worldwide. Due to its high stability and persistence, sucralose has shown widespread occurrence in environmental waters, at concentrations that could reach up to several μg/L. Previous studies have used time consuming sample preparation methods (offline solid phase extraction/derivatization) or methods with rather high detection limits (direct injection) for sucralose analysis. This study described a faster and sensitive analytical method for the determination of sucralose in environmental samples. Results An online SPE-LC–MS/MS method was developed, being capable to quantify sucralose in 12 minutes using only 10 mL of sample, with method detection limits (MDLs) of 4.5 ng/L, 8.5 ng/L and 45 ng/L for deionized water, drinking and reclaimed waters (1:10 diluted with deionized water), respectively. Sucralose was detected in 82% of the reclaimed water samples at concentrations reaching up to 18 μg/L. The monthly average for a period of one year was 9.1 ± 2.9 μg/L. The calculated mass loads per capita of sucralose discharged through WWTP effluents based on the concentrations detected in wastewaters in the U. S. is 5.0 mg/day/person. As expected, the concentrations observed in drinking water were much lower but still relevant reaching as high as 465 ng/L. In order to evaluate the stability of sucralose, photodegradation experiments were performed in natural waters. Significant photodegradation of sucralose was observed only in freshwater at 254 nm. Minimal degradation (<20%) was observed for all matrices under more natural conditions (350 nm or solar simulator). The only photolysis product of sucralose identified by high resolution mass spectrometry was a de-chlorinated molecule at m/z 362.0535, with molecular formula C12H20Cl2O8. Conclusions Online SPE LC-APCI/MS/MS developed in the study was applied to more than 100 environmental samples. Sucralose was frequently detected (>80%) indicating that the conventional treatment process employed in the sewage treatment plants is not efficient for its removal. Detection of sucralose in drinking waters suggests potential contamination of surface and ground waters sources with anthropogenic wastewater streams. Its high resistance to photodegradation, minimal sorption and high solubility indicate that sucralose could be a good tracer of anthropogenic wastewater intrusion into the environment. PMID:23965251

Characterizing the distribution of an endangered salmonid using environmental DNA analysis

USGS Publications Warehouse

Laramie, Matthew B.; Pilliod, David S.; Goldberg, Caren S.

2015-01-01

Determining species distributions accurately is crucial to developing conservation and management strategies for imperiled species, but a challenging task for small populations. We evaluated the efficacy of environmental DNA (eDNA) analysis for improving detection and thus potentially refining the known distribution of Chinook salmon (Oncorhynchus tshawytscha) in the Methow and Okanogan Subbasins of the Upper Columbia River, which span the border between Washington, USA and British Columbia, Canada. We developed an assay to target a 90 base pair sequence of Chinook DNA and used quantitative polymerase chain reaction (qPCR) to quantify the amount of Chinook eDNA in triplicate 1-L water samples collected at 48 stream locations in June and again in August 2012. The overall probability of detecting Chinook with our eDNA method in areas within the known distribution was 0.77 (±0.05 SE). Detection probability was lower in June (0.62, ±0.08 SE) during high flows and at the beginning of spring Chinook migration than during base flows in August (0.93, ±0.04 SE). In the Methow subbasin, mean eDNA concentration was higher in August compared to June, especially in smaller tributaries, probably resulting from the arrival of spring Chinook adults, reduced discharge, or both. Chinook eDNA concentrations did not appear to change in the Okanogan subbasin from June to August. Contrary to our expectations about downstream eDNA accumulation, Chinook eDNA did not decrease in concentration in upstream reaches (0–120 km). Further examination of factors influencing spatial distribution of eDNA in lotic systems may allow for greater inference of local population densities along stream networks or watersheds. These results demonstrate the potential effectiveness of eDNA detection methods for determining landscape-level distribution of anadromous salmonids in large river systems.

Performance of an under-loaded denitrifying bioreactor with biochar amendment.

PubMed

Bock, Emily M; Coleman, Brady S L; Easton, Zachary M

2018-07-01

Denitrifying bioreactors are recently-established agricultural best management practices with growing acceptance in the US Midwest but less studied in other agriculturally significant regions, such as the US Mid-Atlantic. A bioreactor was installed in the Virginia Coastal Plain to evaluate performance in this geographically novel region facing challenges managing nutrient pollution. The 25.3 m 3 woodchip bed amended with 10% biochar (v/v) intercepted subsurface drainage from 6.5 ha cultivated in soy. Influent and effluent nitrate-nitrogen (NO 3 -N) and total phosphorus (TP) concentrations and flowrate were monitored intensively during the second year of operation. Bed surface fluxes of greenhouse gases (GHGs) nitrous oxide (N 2 O), methane (CH 4 ), and carbon dioxide (CO 2 ) were measured periodically with the closed dynamic chamber technique. The bioreactor did not have a statistically or environmentally significant effect on TP export. Cumulative NO 3 -N removal efficiency (9.5%) and average removal rate (0.56 ± 0.25 g m -3  d -1 ) were low relative to Midwest tile bioreactors, but comparable to installations in the Maryland Coastal Plain. Underperformance was attributed mainly to low NO 3 -N loading (mean 9.4 ± 4.4 kg ha -1 yr -1 ), although intermittent flow, periods of low HRT, and low pH (mean 5.3) also likely contributed. N removal rates were correlated with influent NO 3 -N concentration and temperature, but decreased with hydraulic residence time, indicating that removal was often N-limited. GHG emissions were similar to other bioreactors and constructed wetlands and not considered environmentally concerning. This study suggests that expectations of NO 3 -N removal efficiency developed from bioreactors receiving moderate to high NO 3 -N loading with influent concentrations exceeding 10-20 mg L -1 are unlikely to be met by systems where N-limitation becomes significant. Copyright © 2018 Elsevier Ltd. All rights reserved.

Global styrene oligomers monitoring as new chemical contamination from polystyrene plastic marine pollution.

PubMed

Kwon, Bum Gun; Koizumi, Koshiro; Chung, Seon-Yong; Kodera, Yoichi; Kim, Jong-Oh; Saido, Katsuhiko

2015-12-30

Polystyrene (PS) plastic marine pollution is an environmental concern. However, a reliable and objective assessment of the scope of this problem, which can lead to persistent organic contaminants, has yet to be performed. Here, we show that anthropogenic styrene oligomers (SOs), a possible indicator of PS pollution in the ocean, are found globally at concentrations that are higher than those expected based on the stability of PS. SOs appear to persist to varying degrees in the seawater and sand samples collected from beaches around the world. The most persistent forms are styrene monomer, styrene dimer, and styrene trimer. Sand samples from beaches, which are commonly recreation sites, are particularly polluted with these high SOs concentrations. This finding is of interest from both scientific and public perspectives because SOs may pose potential long-term risks to the environment in combination with other endocrine disrupting chemicals. From SOs monitoring results, this study proposes a flow diagram for SOs leaching from PS cycle. Using this flow diagram, we conclude that SOs are global contaminants in sandy beaches around the world due to their broad spatial distribution. Copyright © 2015 Elsevier B.V. All rights reserved.

Multi-species biofilms defined from drinking water microorganisms provide increased protection against chlorine disinfection.

PubMed

Schwering, Monika; Song, Joanna; Louie, Marie; Turner, Raymond J; Ceri, Howard

2013-09-01

A model biofilm, formed of multiple species from environmental drinking water, including opportunistic pathogens, was created to explore the tolerance of multi-species biofilms to chlorine levels typical of water-distribution systems. All species, when grown planktonically, were killed by concentrations of chlorine within the World Health Organization guidelines (0.2-5.0 mg l(-1)). Higher concentrations (1.6-40-fold) of chlorine were required to eradicate biofilm populations of these strains, ~70% of biofilms tested were not eradicated by 5.0 mg l(-1) chlorine. Pathogenic bacteria within the model multi-species biofilms had an even more substantial increase in chlorine tolerance; on average ~700-1100 mg l(-1) chlorine was required to eliminate pathogens from the biofilm, 50-300-fold higher than for biofilms comprising single species. Confocal laser scanning microscopy of biofilms showed distinct 3D structures and multiple cell morphologies and arrangements. Overall, this study showed a substantial increase in the chlorine tolerance of individual species with co-colonization in a multi-species biofilm that was far beyond that expected as a result of biofilm growth on its own.

An evaluation of the urban stormwater pollutant removal efficiency of catch basin inserts.

PubMed

Morgan, Robert A; Edwards, Findlay G; Brye, Kristofor R; Burian, Stephen J

2005-01-01

In a storm sewer system, the catch basin is the interface between surface runoff and the sewer. Responding to the need to improve the quality of stormwater from urban areas and transportation facilities, and spurred by Phase I and II Stormwater Rules from the U.S. Environmental Protection Agency, several companies market catch basin inserts as best management practices for urban water quality management. However, little data have been collected under controlled tests that indicate the pollutant removal efficiency of these inserts when the inflow is near what can be expected to occur in the field. A stormwater simulator was constructed to test inserts under controlled and replicable conditions. The inserts were tested for removal efficiency of total suspended solids (TSS) and total petroleum hydrocarbons (TPH) at an inflow rate of 757 to 814 L/min, with influent pollutant concentrations of 225 mg/L TSS and 30 mg/L TPH. These conditions are similar to stormwater runoff from small commercial sites in the southeastern United States. Results from the tests indicate that at the test flowrate and pollutant concentration, average TSS removal efficiencies ranged from 11 to 42% and, for TPH, the removal efficiency ranged from 10 to 19%.

Longitudinal survey of lead, cadmium, and copper in seagrass Syringodium filiforme from a former bombing range (Vieques, Puerto Rico).

PubMed

Díaz, Elba; Pérez, Dustin; Delgado Acevedo, Johanna; Massol-Deyá, Arturo

2018-01-01

Trace element composition in plant biomass could be used as an indicator of environmental stress, management practices and restoration success. A longitudinal study was conducted to compare Pb, Cd, and Cu content in seagrass Syringodium filiforme collected at a former bombing range in Puerto Rico with those of a Biosphere Reserve under similar geoclimatic conditions. Trace elements were measured by atomic absorption after dry-ashing of samples and extraction with acid. In general, levels of Pb, Cd, and Cu varied during 2001, 2003, 2005-2006, and 2013-2016. Results showed that bioaccumulated concentration of these trace elements were consistently higher, but not significant, at the bombing range site. As expected in polluted areas, greater variability in Pb and Cd content were observed in the military impacted site with levels up to 14 and 17 times higher than seagrass from the reference site, respectively. Although a decrease in Pb was observed after cessation of all military activities in 2003, the concentration in plant biomass was still above levels of ecological concern, indicating that natural attenuation is insufficient for cleanup of the site.

Brain metabolic alterations in mice subjected to postnatal traumatic stress and in their offspring.

PubMed

Gapp, Katharina; Corcoba, Alberto; van Steenwyk, Gretchen; Mansuy, Isabelle M; Duarte, João Mn

2017-07-01

Adverse environmental and social conditions early in life have a strong impact on health. They are major risk factors for mental diseases in adulthood and, in some cases, their effects can be transmitted across generations. The consequences of detrimental stress conditions on brain metabolism across generations are not well known. Using high-field (14.1 T) magnetic resonance spectroscopy, we investigated the neurochemical profile of adult male mice exposed to traumatic stress in early postnatal life and of their offspring, and of undisturbed control mice. We found that, relative to controls, early life stress-exposed mice have metabolic alterations consistent with neuronal dysfunction, including reduced concentration of N-acetylaspartate, glutamate and γ-aminobutyrate, in the prefrontal cortex in basal conditions. Their offspring have normal neurochemical profiles in basal conditions. Remarkably, when challenged by an acute cold swim stress, the offspring has attenuated metabolic responses in the prefrontal cortex, hippocampus and striatum. In particular, the expected stress-induced reduction in the concentration of N-acetylaspartate, a putative marker of neuronal health, was prevented in the cortex and hippocampus. These findings suggest that paternal trauma can confer beneficial brain metabolism adaptations to acute stress in the offspring.

Model for Correlating Real-Time Survey Results to Contaminant Concentrations - 12183

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, Stuart A.

2012-07-01

The U.S. Environmental Protection Agency (EPA) Superfund program is developing a new Counts Per Minute (CPM) calculator to correlate real-time survey results, which are often expressed as counts per minute, to contaminant concentrations that are more typically provided in risk assessments or for cleanup levels, usually expressed in pCi/g or pCi/m{sup 2}. Currently there is no EPA guidance for Superfund sites on correlating count per minute field survey readings back to risk, dose, or other ARAR based concentrations. The CPM calculator is a web-based model that estimates a gamma detector response for a given level of contamination. The intent ofmore » the CPM calculator is to facilitate more real-time measurements within a Superfund response framework. The draft of the CPM calculator is still undergoing internal EPA review. This will be followed by external peer review. It is expected that the CPM calculator will at least be in peer review by the time of WM2012 and possibly finalized at that time. The CPM calculator should facilitate greater use of real-time measurement at Superfund sites. The CPM calculator may also standardize the process of converting lab data to real time measurements. It will thus lessen the amount of lab sampling that is needed for site characterization and confirmation surveys, but it will not remove the need for sampling. (authors)« less

Nowcasting Beach Advisories at Ohio Lake Erie Beaches

USGS Publications Warehouse

Francy, Donna S.; Darner, Robert A.

2007-01-01

Data were collected during the recreational season of 2007 to test and refine predictive models at three Lake Erie beaches. In addition to E. coli concentrations, field personnel collected or compiled data for environmental and water-quality variables expected to affect E. coli concentrations including turbidity, wave height, water temperature, lake level, rainfall, and antecedent dry days and wet days. At Huntington (Bay Village) and Edgewater (Cleveland) during 2007, the models provided correct responses 82.7 and 82.1 percent of the time; these percentages were greater than percentages obtained using the previous day?s E. coli concentrations (current method). In contrast, at Villa Angela during 2007, the model provided correct responses only 61.3 percent of the days monitored. The data from 2007 were added to existing datasets and the larger datasets were split into two (Huntington) or three (Edgewater) segments by date based on the occurrence of false negatives and positives (named ?season 1, season 2, season 3?). Models were developed for dated segments and for combined datasets. At Huntington, the summed responses for separate best models for seasons 1 and 2 provided a greater percentage of correct responses (85.6 percent) than the one combined best model (83.1 percent). Similar results were found for Edgewater. Water resource managers will determine how to apply these models to the Internet-based ?nowcast? system for issuing water-quality advisories during 2008.

Perfluoroalkylsulfonic and carboxylic acids in earthworms (Eisenia fetida): Accumulation and effects results from spiked soils at PFAS concentrations bracketing environmental relevance.

PubMed

Karnjanapiboonwong, Adcharee; Deb, Sanjit K; Subbiah, Seenivasan; Wang, Degeng; Anderson, Todd A

2018-05-01

Effects of perfluorobutanesulfonic acid (PFBS), perfluorohexanesulfonic acid (PFHxS), perfluorononanoic acid (PFNA), and perfluoroheptanoic acid (PFHpA) on earthworms (Eisenia fetida) in soils contaminated with these compounds at 0.1, 1, 10, 1,000, and 100,000 μg kg -1 dry weight, covering concentration levels found in background, biosolid-amended, and facility-surrounding soils, were investigated. Earthworms were exposed to spiked soil for 21 days. Concentrations of these compounds in earthworms after 21-d exposure ranged from below detection to 127 mg kg -1 wet weight with the rank order of PFNA > PFHxS > PFHpA > PFBS; no mortality of earthworms was observed in all treatments including controls, except PFBS at 1,000 μg kg -1 and all PFASs at 100,000 μg kg -1 . The highest weight loss (29%) was observed for earthworms exposed to PFNA at 100,000 μg kg -1 , which was significantly different from all other treatments except PFHpA at 100,000 μg kg -1 . These results are expected to fill some data gaps in toxicity of PFASs in terrestrial environments and provide helpful information on the potential for trophic transport of PFASs from soil to higher organisms. Copyright © 2018 Elsevier Ltd. All rights reserved.

INTERSPECIES CORRELATION ESTIMATES PREDICT PROTECTIVE ENVIRONMENTAL CONCENTRATIONS

EPA Science Inventory

Environmental risk assessments often use multiple single species toxicity test results and species sensitivity distributions (SSDs) to derive a predicted no-effect concentration in the environment, typically the 5th percentile of the SSD, termed the HC5. The shape and location of...

RELATIONSHIPS BETWEEN NEAR-BOTTOM DISSOLVED OXYGEN AND SEDIMENT PROFILE CAMERA MEASUREMENTS

EPA Science Inventory

The United States Environmental Protection Agency (U.S. EPA) and other environmental authorities regulate concentrations of dissolved oxygen (DO) as a measure of nutrient-related eutrophication in estuarine and coastal waters. However, in situ DO concentrations are extremely var...

Assessing decision making and dispute resolution in environmental policy: Regulatory negotiations at the Environmental Protection Agency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lyons, E.A.

This dissertation is an evaluation of the use of negotiations in the rule-making context at the US Environmental Protection Agency (EPA). The goal is to assess the benefits and the limitations of negotiation as a policy process, and to make explicit the values which are expected from a negotiation process as well as the conditions which must be met in order for those values to be realized. Three distinct values are expected of negotiation processes: (1) negotiation is promoted as an efficient process that can save time and money in public decision making by avoiding protracted and expensive legal actions;more » (2) it is expected that a negotiation process which provides a mechanism for reaching accommodation among all competing perspectives can yield good policy outcomes; face-to-face interactions among parties with competing interests should provide opportunities for building better relationships among individuals and also for building community. The usefulness of negotiation as a policy tool is limited by the fact that negotiation is only appropriate in a few select cases in which the issues are mature and the parties affected by the issues are prepared for negotiation.« less

Genetic Factors of Individual Differences in Decision Making in Economic Behavior: A Japanese Twin Study using the Allais Problem.

PubMed

Shikishima, Chizuru; Hiraishi, Kai; Yamagata, Shinji; Ando, Juko; Okada, Mitsuhiro

2015-01-01

Why does decision making differ among individuals? People sometimes make seemingly inconsistent decisions with lower expected (monetary) utility even when objective information of probabilities and reward are provided. It is noteworthy, however, that a certain proportion of people do not provide anomalous responses, choosing the alternatives with higher expected utility, thus appearing to be more "rational." We investigated the genetic and environmental influences on these types of individual differences in decision making using a classical Allais problem task. Participants were 1,199 Japanese adult twins aged 20-47. Univariate genetic analysis revealed that approximately a third of the Allais problem response variance was explained by genetic factors and the rest by environmental factors unique to individuals and measurement error. The environmental factor shared between families did not contribute to the variance. Subsequent multivariate genetic analysis clarified that decision making using the expected utility theory was associated with general intelligence and that the association was largely mediated by the same genetic factor. We approach the mechanism underlying two types of "rational" decision making from the perspective of genetic correlations with cognitive abilities.

Development of an Ultra-Low Background Liquid Scintillation Counter for Trace Level Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erchinger, Jennifer L.; Orrell, John L.; Aalseth, Craig E.

2015-09-01

Low-level liquid scintillation counting (LSC) has been established as one of the radiation detection techniques useful in elucidating environmental processes and environmental monitoring around nuclear facilities. The Ultra-Low Background Liquid Scintillation Counter (ULB-LSC) under construction in the Shallow Underground Laboratory at Pacific Northwest National Laboratory aims to further reduce the MDAs and/or required sample processing. Through layers of passive shielding in conjunction with an active veto and 30 meters water equivalent overburden, the background reduction is expected to be 10 to 100 times below typical analytic low-background liquid scintillation systems. Simulations have shown an expected background of around 14 countsmore » per day. A novel approach to the light collection will use a coated hollow light guide cut into the inner copper shielding. Demonstration LSC measurements will show low-energy detection, spectral deconvolution, and alpha/beta discrimination capabilities, from trials with standards of tritium, strontium-90, and actinium-227, respectively. An overview of the system design and expected demonstration measurements will emphasize the potential applications of the ULB-LSC in environmental monitoring for treaty verification, reach-back sample analysis, and facility inspections.« less

Structural stability as a consistent predictor of phenological events.

PubMed

Song, Chuliang; Saavedra, Serguei

2018-06-13

The timing of the first and last seasonal appearance of a species in a community typically follows a pattern that is governed by temporal factors. While it has been shown that changes in the environment are linked to phenological changes, the direction of this link appears elusive and context-dependent. Thus, finding consistent predictors of phenological events is of central importance for a better assessment of expected changes in the temporal dynamics of ecological communities. Here we introduce a measure of structural stability derived from species interaction networks as an estimator of the expected range of environmental conditions compatible with the existence of a community. We test this measure as a predictor of changes in species richness recorded on a daily basis in a high-arctic plant-pollinator community during two spring seasons. We find that our measure of structural stability is the only consistent predictor of changes in species richness among different ecological and environmental variables. Our findings suggest that measures based on the notion of structural stability can synthesize the expected variation of environmental conditions tolerated by a community, and explain more consistently the phenological changes observed in ecological communities. © 2018 The Author(s).

The influence of biological and environmental factors on metallothionein concentration in the blood.

PubMed

Kowalska, Katarzyna; Bizoń, Anna; Zalewska, Marta; Milnerowicz, Halina

2015-01-01

The concentration of metallothionein (MT), a low-molecular-weight protein, is regulated by many factors, primarily metals (zinc, cadmium, copper), cytokines, glucocorticoides and free radicals. These factors are determined by such aspects of human biology as gender, pregnancy and age, as well as by environmental factors including the use of oral contraceptives and cigarette smoking, all which may affect MT levels in the body. The aim of this study was to investigate the influence of these biological and environmental factors on MT concentrations in erythrocyte lysate and in plasma. MT concentrations were determined by a two-step direct enzyme-linked immunosorbent assay. Evaluation of exposure to cigarette smoking was performed by checking cotinine levels in the plasma of subjects. The studies showed higher MT concentrations in both the erythrocyte lysate and plasma of women when compared to men. Furthermore, pregnancy causes an increase of MT concentration in plasma, while oral contraceptives cause an elevated concentration of MT in erythrocyte lysate. Age impacts plasma MT concentrations in men, whereas it does not affect concentrations of MT in erythrocyte lysate. Copyright © 2014 Elsevier GmbH. All rights reserved.

Environmental optimization of chromium recovery from tannery sludge using a life cycle assessment approach.

PubMed

Kiliç, Eylem; Puig, Rita; Baquero, Grau; Font, Joaquim; Colak, Selime; Gürler, Deniz

2011-08-15

Life cycle assessment (LCA) was used to evaluate the environmental impact of an oxidative chromium recovery method from tannery sludge, in comparison with the usual landfilling process. Three improvement options (water reduction, byproduct use and anaerobic sludge digestion) were considered. The results showed that the proposed chromium recovery process would be better environmentally than conventional landfilling in all the evaluated impact categories if the amount of chromium recovered was 43 kg per ton of sludge. This amount could be recovered if the chromium concentration was about 20 times higher than that considered in this study. Alternatively, a lower chromium concentration would produce a better result if the recovery method was optimized and implemented at industrial rather than laboratory scale, and if more accurate data were provided on environmental credits for avoiding the chromium production process. Thus, the recovery method is environmentally beneficial when tannery sludge contains a chromium concentration of about 100,000 ppm. According to the literature, such concentrations are not unusual. The results could serve as the basis for further environmental improvements in chromium recovery and tannery sludge management and should be used in decision-making processes, especially for end-of-pipe treatments. Copyright © 2011 Elsevier B.V. All rights reserved.

Toddler's Mastery Motivation and Maternal Expectations: Urban Puerto Rican and Dominican Mothers and Children.

ERIC Educational Resources Information Center

Knauf, Diana E.; Bobadilla, Wendy V.; Busch-Rossnagel, Nancy A.

Mastery motivation is considered important because it promotes competence and is believed to be the precursor to achievement motivation. Focusing on toddlers between 16 and 22 months old, this study examined the relationship between mastery motivation and environmental contributors, such as maternal expectations, and cultural orientation in Puerto…

Examining Social Climate and Youth Social Goals on Extended Wilderness Courses: A Path toward Improving Participant Experiences

ERIC Educational Resources Information Center

Mirkin, Benjamin J.

2013-01-01

This dissertation examined participants' expectations of the social climate on extended wilderness courses, how students' actually experienced the social climate during their course, and how these expectations, perceptions and the influence of environmental characteristics, impacted their goals for peer interactions. Pre and posttest surveys were…

77 FR 49856 - Environmental Impact Statement for the Salinas to San Luis Obispo Portion of the Coast Corridor...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-17

... likely to worsen, making travel times unreliable. In addition, space constraints limit the potential to... activity is expected to generate increased travel demand. By 2040, statewide population is expected to grow... continuing transportation challenges as evidenced by the following: Constrained Travel Options--While the...

Hanford Site near-facility environmental monitoring annual report, calendar year 1997

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perkins, C.J.

1998-07-28

Near-facility environmental monitoring provides a means to measure the impacts of operations, waste management, and remediation activities on the environment adjacent to facilities and ensure compliance with local, state, and federal environmental regulations. Specifically, near-facility environmental monitoring monitors new and existing sites, processes, and facilities for potential impacts and releases; fugitive emissions and diffuse sources associated with contaminated areas, facilities (both active and those undergoing surveillance and maintenance), and environmental restoration activities. External radiation, ambient air particulates, ground and surface water, soil, sediment, and biota (plants and animals) are sampled or monitored. Parameters include, as appropriate, radionuclides; radiation fields; chemicalmore » or physical constituents, such as nitrates; pH; and water temperature. All ambient air results were below the US Department of Energy (DOE) Derived Concentration Guides (DCGs). Groundwater concentrations at the two wells at the 107-N Facility were below both the DOE DCG and US Environmental Protection Agency Interim Drinking Water Standards for gamma emitting radionuclides. Soil and vegetation results were generally within historic ranges and mostly below the Accessible Soil Concentration limits (included in HNF-PRO-454, Inactive Waste Sites) with the exception of one soil sampling location at 1 00 N Area. External radiation fields continued an overall downward trend. Surface water disposal unit samples (water, sediment, and aquatic vegetation) showed radionuclide concentrations below their respective DCG and Accessible Soil Concentration limits. The 100 N Area Columbia river shoreline springs results were below DCGs with the exception of one Sr concentration. More than 4,600 ha (11,300 acres) of radiologically controlled areas were surveyed in 1997, approximately the same as in 1996.« less

Revisions to US EPA Superfund Risk and Dose Assessment Models and Guidance - 13403

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, Stuart A.

2013-07-01

The U.S. Environmental Protection Agency (EPA) Superfund program's six Preliminary Remediation Goal (PRG) and Dose Compliance Concentration (DCC) internet based calculators for risk and dose assessment at Superfund sites are being revised to reflect better science, revisions to existing exposure scenarios and new scenarios, and changes to match up more closely with the EPA chemical regional screening level calculator. A revised version of the 1999 guidance document that provides an overview for the Superfund risk assessment process at radioactively contaminated sites, 'Radiation Risk Assessment At CERCLA Sites: Q and A', is being completed that will reflect Superfund recommended guidance andmore » other technical documents issued over the past 13 years. EPA is also issuing a series of fact sheets in the document 'Superfund Radiation Risk Assessment: A Community Tool-kit'. This presentation would go over those changes that are expected to be finished by this spring. (authors)« less

Pesticide risk assessment in free-ranging bees is weather and landscape dependent.

PubMed

Henry, Mickaël; Bertrand, Colette; Le Féon, Violette; Requier, Fabrice; Odoux, Jean-François; Aupinel, Pierrick; Bretagnolle, Vincent; Decourtye, Axel

2014-07-10

The risk assessment of plant protection products on pollinators is currently based on the evaluation of lethal doses through repeatable lethal toxicity laboratory trials. Recent advances in honeybee toxicology have, however, raised interest on assessing sublethal effects in free-ranging individuals. Here, we show that the sublethal effects of a neonicotinoid pesticide are modified in magnitude by environmental interactions specific to the landscape and time of exposure events. Field sublethal assessment is therefore context dependent and should be addressed in a temporally and spatially explicit way, especially regarding weather and landscape physiognomy. We further develop an analytical Effective Dose (ED) framework to help disentangle context-induced from treatment-induced effects and thus to alleviate uncertainty in field studies. Although the ED framework involves trials at concentrations above the expected field exposure levels, it allows to explicitly delineating the climatic and landscape contexts that should be targeted for in-depth higher tier risk assessment.

Development of an atmospheric monitoring plan for space station

NASA Technical Reports Server (NTRS)

Casserly, Dennis M.

1989-01-01

An environmental health monitoring plan for Space Station will ensure crew health during prolonged habitation. The Space Station, Freedom, will operate for extended periods, 90+ days, without resupply. A regenerative, closed loop life support system will be utilized in order to minimize resupply logistics and costs. Overboard disposal of wastes and venting of gases to space will be minimal. All waste material will be treated and recycled. The concentrated wastes will be stabilized and stored for ground disposal. The expected useful life of the station (decades) and the diversity of materials brought aboard for experimental or manufacturing purposes, increases the likelihood of cabin contamination. Processes by which cabin contamination can occur include: biological waste production, material off-gassing, process leakage, accidental containment breach, and accumulation due to poor removal efficiencies of the purification units. An industrial hygiene approach was taken to rationalize monitoring needs and to identify the substances likely to be present, the amount, and their hazard.

Guided cracking of electrodes by stretching prism-patterned membrane electrode assemblies for high-performance fuel cells.

PubMed

Ahn, Chi-Yeong; Jang, Segeun; Cho, Yong-Hun; Choi, Jiwoo; Kim, Sungjun; Kim, Sang Moon; Sung, Yung-Eun; Choi, Mansoo

2018-01-19

Guided cracks were successfully generated in an electrode using the concentrated surface stress of a prism-patterned Nafion membrane. An electrode with guided cracks was formed by stretching the catalyst-coated Nafion membrane. The morphological features of the stretched membrane electrode assembly (MEA) were investigated with respect to variation in the prism pattern dimension (prism pitches of 20 μm and 50 μm) and applied strain (S ≈ 0.5 and 1.0). The behaviour of water on the surface of the cracked electrode was examined using environmental scanning electron microscopy. Guided cracks in the electrode layer were shown to be efficient water reservoirs and liquid water passages. The MEAs with and without guided cracks were incorporated into fuel cells, and electrochemical measurements were conducted. As expected, all MEAs with guided cracks exhibited better performance than conventional MEAs, mainly because of the improved water transport.

New insights into co-digestion of activated sludge and food waste: Biogas versus biofertilizer.

PubMed

Ma, Yingqun; Yin, Yao; Liu, Yu

2017-10-01

This study explored two holistic approaches for co-digestion of activated sludge and food waste. In Approach 1, mixed activated sludge and food waste were first hydrolyzed with fungal mash, and produced hydrolysate without separation was directly subject to anaerobic digestion. In Approach 2, solid generated after hydrolysis of food waste by fungal mash was directly converted to biofertilizer, while separated liquid with high soluble COD concentration was further co-digested with activated sludge for biomethane production. Although the potential energy produced from Approach 1 was about 1.8-time higher than that from Approach 2, the total economic revenue generated from Approach 2 was about 1.9-fold of that from Approach 1 due to high market value of biofertilizer. It is expected that this study may lead to a paradigm shift in biosolid management towards environmental and economic sustainability. Copyright © 2017 Elsevier Ltd. All rights reserved.

Synthetic mixed-signal computation in living cells

PubMed Central

Rubens, Jacob R.; Selvaggio, Gianluca; Lu, Timothy K.

2016-01-01

Living cells implement complex computations on the continuous environmental signals that they encounter. These computations involve both analogue- and digital-like processing of signals to give rise to complex developmental programs, context-dependent behaviours and homeostatic activities. In contrast to natural biological systems, synthetic biological systems have largely focused on either digital or analogue computation separately. Here we integrate analogue and digital computation to implement complex hybrid synthetic genetic programs in living cells. We present a framework for building comparator gene circuits to digitize analogue inputs based on different thresholds. We then demonstrate that comparators can be predictably composed together to build band-pass filters, ternary logic systems and multi-level analogue-to-digital converters. In addition, we interface these analogue-to-digital circuits with other digital gene circuits to enable concentration-dependent logic. We expect that this hybrid computational paradigm will enable new industrial, diagnostic and therapeutic applications with engineered cells. PMID:27255669

Bacteriological water quality in the Lake Pontchartrain basin Louisiana following Hurricanes Katrina and Rita, September 2005

USGS Publications Warehouse

Stoeckel, Donald M.; Bushon, Rebecca N.; Demcheck, Dennis K.; Skrobialowski, Stanley C.; Kephart, Christopher M.; Bertke, Erin E.; Mailot, Brian E.; Mize, Scott V.; Fendick, Robert B.

2005-01-01

The U.S. Geological Survey (USGS), in collaboration with the Louisiana Department of Environmental Quality, monitored bacteriological quality of water at 22 sites in and around Lake Pontchartrain, La., for three consecutive weeks beginning September 13, 2005, following hurricanes Katrina and Rita and the associated flooding. Samples were collected and analyzed by USGS personnel from the USGS Louisiana Water Science Center and the USGS Ohio Water Microbiology Laboratory. Fecal-indicator bacteria (Escherichia coli, enterococci, and fecal coliform) concentrations ranged from the detection limit to 36,000 colony-forming units per 100 milliliters. Data are presented in tabular form and as plots of data in the context of available historical data and water-quality standards and criteria for each site sampled. Quality-control data were reviewed to ensure that methods performed as expected in a mobile laboratory setting.

Seismotectonic, structural, volcanologic, and geomorphic study of New Zealand; indigenous forest assessment in New Zealand; mapping, land use, and environmental studies in New Zealand, volume 1

NASA Technical Reports Server (NTRS)

Probine, M. C.; Suggate, R. P.; Mcgreevy, M. G.; Stirling, I. F. (Principal Investigator)

1977-01-01

The author has identified the following significant results. Results of the atmospheric extinction measurements show clearly the greater opacity of the atmosphere in MSS band 4 which is due to Rayleigh scattering. Atmospheric water vapor absorbs strongly in a wide region between 900 nm and 1000 nm, and this results in a consistently higher extinction coefficient than would otherwise be expected in MSS band 7. The short term fluctuations tend to be greater in band 7 than in the other bands, and this effect is probably due to variations of water vapor concentration in the instrument line of sight. These high extinction coefficients and short term fluctuations in band 7 were observed at Menindee which is in a semi-desert region in western New South Wales.

Hydrogen peroxide contributes to the ultraviolet-B (280-315 nm) induced oxidative stress of plant leaves through multiple pathways.

PubMed

Czégény, Gyula; Wu, Min; Dér, András; Eriksson, Leif A; Strid, Åke; Hideg, Éva

2014-06-27

Solar UV-B (280-315 nm) radiation is a developmental signal in plants but may also cause oxidative stress when combined with other environmental factors. Using computer modeling and in solution experiments we show that UV-B is capable of photosensitizing hydroxyl radical production from hydrogen peroxide. We present evidence that the oxidative effect of UV-B in leaves is at least twofold: (i) it increases cellular hydrogen peroxide concentrations, to a larger extent in pyridoxine antioxidant mutant pdx1.3-1 Arabidopsis and; (ii) is capable of a partial photo-conversion of both 'natural' and 'extra' hydrogen peroxide to hydroxyl radicals. As stress conditions other than UV can increase cellular hydrogen peroxide levels, synergistic deleterious effects of various stresses may be expected already under ambient solar UV-B. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Trends in ecosystem water use efficiency are potentially amplified by plasticity in plant functional traits

NASA Astrophysics Data System (ADS)

Mastrotheodoros, Theodoros; Pappas, Christoforos; Molnar, Peter; Burlando, Paolo; Keenan, Trevor F.; Gentine, Pierre; Fatichi, Simone

2017-04-01

Increasing atmospheric carbon dioxide concentrations stimulate photosynthesis and reduce stomatal conductance, modifying plant water use efficiency. We analyzed eddy covariance flux tower observations from 20 forested ecosystems across the Northern Hemisphere. For these sites, a previous study showed an increase in inherent water use efficiency (IWUE) five times greater than expectations. We used an updated dataset and robust uncertainty quantification to analyze these contemporary trends in IWUE. We found that IWUE increased in the last 15-20 years by roughly 1.4% yr-1, which is less than previously reported, but still 2.8 times greater than theoretical expectations. Numerical simulations by means of an ecosystem model based on temporally static plant functional traits (i.e. model parameters) do not reproduce this increase. We tested the hypothesis that the observed increase in IWUE could be attributed to changes in plant functional traits, potentially triggered by environmental changes. Simulation results accounting for trait plasticity (i.e. by changing model parameters such as specific leaf area and maximum Rubisco capacity) match the observed trends in IWUE, with an increase in both leaf internal CO2 concentration and gross ecosystem production (GEP), and with a negligible trend in evapotranspiration (ET). This supports the hypothesis that changes in plant functional traits of about 1.0% yr-1 can explain the observed IWUE trends and are consistent with observed trends of GEP and ET at larger scales. Our results highlight that at decadal or longer time scales trait plasticity can considerably influence the water, carbon and energy fluxes with implications for both the monitoring of temporal changes in plant traits and their representation in Earth system models.

Main predictors of periphyton species richness depend on adherence strategy and cell size

PubMed Central

Siqueira, Tadeu; Landeiro, Victor Lemes; Rodrigues, Liliana; Bonecker, Claudia Costa; Rodrigues, Luzia Cleide; Santana, Natália Fernanda; Thomaz, Sidinei Magela; Bini, Luis Mauricio

2017-01-01

Periphytic algae are important components of aquatic ecosystems. However, the factors driving periphyton species richness variation remain largely unexplored. Here, we used data from a subtropical floodplain (Upper Paraná River floodplain, Brazil) to quantify the influence of environmental variables (total suspended matter, temperature, conductivity, nutrient concentrations, hydrology, phytoplankton biomass, phytoplankton species richness, aquatic macrophyte species richness and zooplankton density) on overall periphytic algal species richness and on the richness of different algal groups defined by morphological traits (cell size and adherence strategy). We expected that the coefficients of determination of the models estimated for different trait-based groups would be higher than the model coefficient of determination of the entire algal community. We also expected that the relative importance of explanatory variables in predicting species richness would differ among algal groups. The coefficient of determination for the model used to predict overall periphytic algal species richness was higher than the ones obtained for models used to predict the species richness of the different groups. Thus, our first prediction was not supported. Species richness of aquatic macrophytes was the main predictor of periphyton species richness of the entire community and a significant predictor of the species richness of small mobile, large mobile and small-loosely attached algae. Abiotic variables, phytoplankton species richness, chlorophyll-a concentration, and hydrology were also significant predictors, depending on the group. These results suggest that habitat heterogeneity (as proxied by aquatic macrophytes richness) is important for maintaining periphyton species richness in floodplain environments. However, other factors played a role, suggesting that the analysis of species richness of different trait-based groups unveils relationships that were not detectable when the entire community was analysed together. PMID:28742122

Environmental Education Saves the Day

ERIC Educational Resources Information Center

Haines, Sarah; Kilpatrick, Cynthia

2007-01-01

At the start of each school year at Oil City Elementary Magnet School in Oil City, Louisiana, eager students ask, "What's our theme this year?" This curiosity comes from their expectations that they will study a different environmental concept each year. Kindergarten classes learn to "Be a Friend to the Earth," followed by life…

Simulating the effect of brush management on runoff and erosion on the Walnut Gulch Experimental Watershed

USDA-ARS?s Scientific Manuscript database

The Conservation Effects Assessment Project (CEAP)-Grazing Lands national assessment is designed to quantify the environmental effects of conservation practices on U.S. non-Federal grazing lands. The assessment includes science-based estimates of expected environmental effects of installed conservat...

Personal and Environmental Influences on Students' Beliefs about Effective Study Strategies.

ERIC Educational Resources Information Center

Nolen, Susan Bobbitt; Haladyna, Thomas M.

1990-01-01

A model of personal and environmental influences on students' valuing of two deep-processing strategies for studying expository texts is described. Questionnaire data from 281 high school science students indicated that students' task orientation and perceptions about teacher expectations were central to students' attitudes. (TJH)

Place-Based Environmental Education in the Ontario Secondary School Curriculum

ERIC Educational Resources Information Center

Mnyusiwalla, Laila; Bardecki, Michal

2017-01-01

This study reviews the Ontario secondary school curriculum in light of recommendations made by the 2007 Bondar Report, "Shaping Our Schools, Shaping Our Future." It analyzes curriculum expectations and enrollment data for the purpose of reporting upon and providing recommendations for place-based environmental education. The extent and…

Endogenous circadian regulation of carbon dioxide exchange in terrestrial ecosystems

Treesearch

Victor Resco de Dios; Michael L. Goulden; Kiona Ogle; Andrew D. Richardson; David Y. Hollinger; Eric A. Davidson; Josu G. Alday; Greg A. Barron-Gafford; Arnaud Carrara; Andrew S. Kowalski; Walt C. Oechel; Borja R. Reverter; Russell L. Scott; Ruth K. Varner; Ruben Diaz-Sierra; Jose M. Moreno

2012-01-01

It is often assumed that daytime patterns of ecosystem carbon assimilation are mostly driven by direct physiological responses to exogenous environmental cues. Under limited environmental variability, little variation in carbon assimilation should thus be expected unless endogenous plant controls on carbon assimilation, which regulate photosynthesis in time, are active...

Approaching messy problems: strategies for environmental analysis

Treesearch

L. M. Reid; R. R. Ziemer; T. E. Lisle

1996-01-01

Environmental problems are never neatly defined. Instead, each is a tangle of interacting processes whose manifestation and interpretation are warped by the vagaries of time, weather, expectation, and economics. Each problem involves livelihoods, values, and numerous specialized disciplines. Nevertheless, federal agencies in the Pacific Northwest have been given the...

100% Renewables as a Focus for Environmental Education

ERIC Educational Resources Information Center

Adlong, William

2012-01-01

The rapid development of renewable energy technologies has a number of implications for environmental educators and educators more generally. The costs of a number of renewable energy technologies are expected to be competitive with fossil fuels within 10-15 years and some installations are competitive already. From 2006-2011 global installations…

A data envelopment analysis approach to compare the environmental efficiency of energy technologies and countries

USDA-ARS?s Scientific Manuscript database

Due to increasing financial and environmental concerns, governmental rules, regulations and incentives alternative energy sources are soon expected to grow at a much faster pace than conventional sources of energy. However, the current body of research providing comparative decision making models fo...

PROTECTING OUR CHILDREN FROM HARM: MEASURING ENVIRONMENTAL RISKS TO CHILDREN REQUIRES UNDERSTANDING THEIR UNIQUE MEANS OF EXPOSURE

EPA Science Inventory

Children's exposures to consumer products and environmental contaminants are expected to be different and, in some cases, much higher than adult's exposures. The objectives of our children's exposure research at the National Exposure Research Laboratory are to make use of exis...

33 CFR 230.25 - Environmental review and consultation requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Principles and Guidelines for Water and Related Land Resources Implementation Studies. Reviews and... of the ongoing studies are not expected to materially affect the decision on the proposed action, the filing of the final EIS need not be delayed. (b) Executive Order 12114, Environmental Effects Abroad of...

33 CFR 230.25 - Environmental review and consultation requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Principles and Guidelines for Water and Related Land Resources Implementation Studies. Reviews and... of the ongoing studies are not expected to materially affect the decision on the proposed action, the filing of the final EIS need not be delayed. (b) Executive Order 12114, Environmental Effects Abroad of...

33 CFR 230.25 - Environmental review and consultation requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Principles and Guidelines for Water and Related Land Resources Implementation Studies. Reviews and... of the ongoing studies are not expected to materially affect the decision on the proposed action, the filing of the final EIS need not be delayed. (b) Executive Order 12114, Environmental Effects Abroad of...

33 CFR 230.25 - Environmental review and consultation requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Principles and Guidelines for Water and Related Land Resources Implementation Studies. Reviews and... of the ongoing studies are not expected to materially affect the decision on the proposed action, the filing of the final EIS need not be delayed. (b) Executive Order 12114, Environmental Effects Abroad of...

33 CFR 230.25 - Environmental review and consultation requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Principles and Guidelines for Water and Related Land Resources Implementation Studies. Reviews and... of the ongoing studies are not expected to materially affect the decision on the proposed action, the filing of the final EIS need not be delayed. (b) Executive Order 12114, Environmental Effects Abroad of...

Noise Monitoring Titan III D Launch Vandenberg AFB, Calif

DTIC Science & Technology

1975-01-01

ent weather conditions. d. Estimated Environmental Impact : (1) The impact of any single noise event is difficult to determine when one is concerned...from average atmospheric conditions should be considered when extrapolating these data. 2. No significant environmental impact is expected to result...AD-A012 748 NOISE MONITORING TITAN III D LAUNCH VANDENBERG AIR FORCE BASE, CALIFORNIA Ronald D. Burnett Environmental Health Laboratory McClellan Air

Distribution of uranium and thorium in groundwater of arid climate region

NASA Astrophysics Data System (ADS)

Murad, Ahmed; Alshamsi, Dalal; Aldahan, Ala; Hou, Xiaolin

2014-05-01

Uranium, thorium and their decay products are the most common radionuclides in groundwater in addition to potassium-40. Once groundwater is used for drinking, domestic and irrigation purposes, the radionuclides will then pose environmental and health related hazard originating from radioactivity and toxicity. In the investigation presented here, assessment of 238U, 235U and 232Th concentrations in groundwater across of the United Arab Emirates (UAE) is evaluated in terms of quality and sources. The region is dominated by arid climate conditions and radioactivity assessment of groundwater is essential for safe use of groundwater. Furthermore, the results were linked to data from other arid regions and worldwide. Groundwater samples (total dissolved solids,TDS, 142.5 mg L-1 to 12770 mg L-1) from 67 different wells were collected across geomorphologically different areas and most of the wells are actively used for agriculture. The aquifers are recent sand dunes, Quaternary (3 million years to present) sediments, and older carbonate rocks (230-10 million years). The 235U, 238U and 232Th measurements were carried out using ICP-MS system equipped with an Xt-skimmer cone and a concentric nebulizer under hot plasma conditions. Concentrations of 235U, 238U and 232Th range at (0.125-508.4) ng L-1, (25.81-69237) ng L-1 and (0.236-2529) ng L-1, respectively. Apparently, most 235U, 238U, 232Th concentrations in the sampled groundwater are below the WHO proposed permissible level of 60000 ng/L for total uranium (1 Bq L-1 for 235U and 10 Bq L-1 for 238U) and 5000 ng L-1 (1Bq L-1) for 232Th. A few samples show high concentrations of uranium that are associated with high TDS values and occur within interbedded limestones and shales aquifer. Comparison with worldwide groundwater data suggests that 238U concentration is highest in the arid regions groundwater where the recharge to aquifers is relatively low. The situation for 232Th concentrations seems less affected by climatic conditions, most likely is related to its less solubility in water compared to uranium. We calculated the accumulated TU and 232Th concentration in the irrigation water annually to estimate the cumulative concentrations after twenty years on specific agricultural areas. The TU and 232Th are expected not to reach more than 1.14 x 10-3 g (1.14 mg) and 4.32 x 10-6 g (4.32 μg) respectively after twenty years if the daily irrigation is at its maximum amount (10 m3). Despite these obtained values of concentrations in irrigation water, the transfer of uranium and thorium into crop is not readily and it is expected that only a tiny fraction of the element end into the body. However, further research is needed to quantify the dietary exposures in the UAE with detailed data from crops and consumers.

Aiding eco-labelling process and its implementation: Environmental Impact Assessment Methodology to define Product Category Rules for canned anchovies.

PubMed

Laso, Jara; Margallo, María; Fullana, Pére; Bala, Alba; Gazulla, Cristina; Irabien, Ángel; Aldaco, Rubén

2017-01-01

To be able to fulfil high market expectations for a number of practical applications, Environmental Product Declarations (EPDs) have to meet and comply with specific and strict methodological prerequisites. These expectations include the possibility to add up Life Cycle Assessment (LCA)-based information in the supply chain and to compare different EPDs. To achieve this goal, common and harmonized calculation rules have to be established, the so-called Product Category Rules (PCRs), which set the overall LCA calculation rules to create EPDs. This document provides PCRs for the assessment of the environmental performance of canned anchovies in Cantabria Region based on an Environmental Sustainability Assessment (ESA) method. This method uses two main variables: the natural resources sustainability (NRS) and the environmental burdens sustainability (EBS). To reduce the complexity of ESA and facilitate the decision-making process, all variables are normalized and weighted to obtain two global dimensionless indexes: resource consumption (X 1 ) and environmental burdens (X 2 ). •This paper sets the PCRs adapted to the Cantabrian canned anchovies.•ESA method facilitates the product comparison and the decision-making process.•This paper stablishes all the steps that an EPD should include within the PCRs of Cantabrian canned anchovies.

Global mammal beta diversity shows parallel assemblage structure in similar but isolated environments

PubMed Central

Graham, Catherine H.; Brooks, Thomas M.; Rondinini, Carlo; Hedges, S. Blair; Davidson, Ana D.; Costa, Gabriel C.

2016-01-01

The taxonomic, phylogenetic and trait dimensions of beta diversity each provide us unique insights into the importance of historical isolation and environmental conditions in shaping global diversity. These three dimensions should, in general, be positively correlated. However, if similar environmental conditions filter species with similar trait values, then assemblages located in similar environmental conditions, but separated by large dispersal barriers, may show high taxonomic, high phylogenetic, but low trait beta diversity. Conversely, we expect lower phylogenetic diversity, but higher trait biodiversity among assemblages that are connected but are in differing environmental conditions. We calculated all pairwise comparisons of approximately 110 × 110 km grid cells across the globe for more than 5000 mammal species (approx. 70 million comparisons). We considered realms as units representing geographical distance and historical isolation and biomes as units with similar environmental conditions. While beta diversity dimensions were generally correlated, we highlight geographical regions of decoupling among beta diversity dimensions. Our analysis shows that assemblages from tropical forests in different realms had low trait dissimilarity while phylogenetic beta diversity was significantly higher than expected, suggesting potential convergent evolution. Low trait beta diversity was surprisingly not found between isolated deserts, despite harsh environmental conditions. Overall, our results provide evidence for parallel assemblage structure of mammal assemblages driven by environmental conditions at a global scale. PMID:27559061

Modeling Geographic and Demographic Variability in Residential Concentrations of Environmental Tobacco Smoke Using National Data Sets

EPA Science Inventory

Despite substantial attention toward environmental tobacco smoke (ETS) exposure, previous studies have not provided adequate information to apply broadly within community-scale risk assessments. We aim to estimate residential concentrations of particulate matter (PM) from ETS in ...

Ambient aerosols remain highly acidic despite dramatic sulfate reductions

NASA Astrophysics Data System (ADS)

Nenes, Athanasios; Weber, Rodney; Guo, Hongyu; Russell, Armistead

2016-04-01

The pH of fine particles has many vital environmental impacts. By affecting aerosol concentrations, chemical composition and toxicity, particle pH is linked to regional air quality and climate, and adverse effects on human health. Sulfate is often the main acid component that drives pH of fine particles (i.e., PM2.5) and is neutralized to varying degrees by gas phase ammonia. Sulfate levels have decreased by approximately 70% over the Southeastern United States in the last fifteen years, but measured ammonia levels have been fairly steady implying the aerosol may becoming more neutral. Using a chemically comprehensive data set, combined with a thermodynamic analysis, we show that PM2.5 in the Southeastern U.S. is highly acidic (pH between 0 and 2), and that pH has remained relatively unchanged throughout the past decade and a half of decreasing sulfate. Even with further sulfate reductions, pH buffering by gas-particle partitioning of ammonia is expected to continue until sulfate drops to near background levels, indicating that fine particle pH will remain near current levels into the future. These results are non-intuitive and reshape expectations of how sulfur emission reductions impact air quality in the Southeastern U.S. and possibly other regions across the globe.

Linking plant functional trait plasticity and the large increase in forest water use efficiency

NASA Astrophysics Data System (ADS)

Mastrotheodoros, Theodoros; Pappas, Christoforos; Molnar, Peter; Burlando, Paolo; Keenan, Trevor F.; Gentine, Pierre; Gough, Christopher M.; Fatichi, Simone

2017-09-01

Elevated atmospheric CO2 concentrations are expected to enhance photosynthesis and reduce stomatal conductance, thus increasing plant water use efficiency. A recent study based on eddy covariance flux observations from Northern Hemisphere forests showed a large increase in inherent water use efficiency (IWUE). Here we used an updated version of the same data set and robust uncertainty quantification to revisit these contemporary IWUE trends. We tested the hypothesis that the observed IWUE increase could be attributed to interannual trends in plant functional traits, potentially triggered by environmental change. We found that IWUE increased by 1.3% yr-1, which is less than previously reported but still larger than theoretical expectations. Numerical simulations with the Tethys-Chloris ecosystem model using temporally static plant functional traits cannot explain this increase. Simulations with plant functional trait plasticity, i.e., temporal changes in model parameters such as specific leaf area and maximum Rubisco capacity, match the observed trends in IWUE. Our results show that trends in plant functional traits, equal to 1.0% yr-1, can explain the observed IWUE trends. Thus, at decadal or longer time scales, trait plasticity could potentially influence forest water, carbon, and energy fluxes with profound implications for both the monitoring of temporal changes in plant functional traits and their representation in Earth system models.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoffman, M.

Six months after Saddam Hussein's torching of more than 700 Kuwaiti oil wells, health officials, meteorologists, and environmental experts convened during mid-August in Cambridge, Massachusetts, to assess the impact of the fires. The soot cloud produced by the fires hasn't produced a nuclear winter, nor are the carbon dioxide and other gases released going to have an appreciable effect on global warming, although regional weather changes are possible. So far adverse health effects from the heavy pall of pollution caused by the fires have been surprisingly mild. This isn't to say that premature deaths will not occur, but many scientistsmore » had feared much worse. Nevertheless, all researchers concede that the data for this particular conclusion are still preliminary, and they expressed concerns that health problems may worsen in the coming months. Most of the health effects are expected in a region blanketed by a plume of smoke 800 to 1,000 kilometers long. The average concentrations of the primary pollutants it contains, carbon-based particles and sulfur dioxide, are similar to those in any large urban center. Still, the oil fires increase the pollution burden on Kuwait, which already had a problem with particulates in the air, and some epidemiologists expect that the extra pollutants will take their toll.« less

Glucocorticoid activity detected by in vivo zebrafish assay and in vitro glucocorticoid receptor bioassay at environmental relevant concentrations.

PubMed

Chen, Qiyu; Jia, Ai; Snyder, Shane A; Gong, Zhiyuan; Lam, Siew Hong

2016-02-01

Glucocorticoids are pharmaceutical contaminants of emerging concern due to their incomplete removal during wastewater treatment, increased presence in aquatic environment and their biological potency. The zebrafish is a popular model for aquatic toxicology and environmental risk assessment. This study aimed to determine if glucocorticoids at environmental concentrations would perturb expression of selected glucocorticoid-responsive genes in zebrafish and to investigate their potentials as an in vivo zebrafish assay in complementing in vitro glucocorticoid receptor bioassay. The relative expression of eleven glucocorticoid-responsive genes in zebrafish larvae and liver of adult male zebrafish exposed to three representative glucocorticoids (dexamethasone, prednisolone and triamcinolone) was determined. The expression of pepck, baiap2 and pxr was up-regulated in zebrafish larvae and the expression of baiap2, pxr and mmp-2 was up-regulated in adult zebrafish exposed to glucocorticoids at concentrations equivalent to total glucocorticoids reported in environmental samples. The responsiveness of the specific genes were sufficiently robust in zebrafish larvae exposed to a complex environmental sample detected with in vitro glucocorticoid activity equivalent to 478 pM dexamethasone (DEX-EQ) and confirmed to contain low concentration (0.2 ng/L or less) of the targeted glucocorticoids, and possibly other glucocorticoid-active compounds. The findings provided in vivo relevance to the in vitro glucocorticoid activity and suggested that the environmental sample can perturb glucocorticoid-responsive genes in its original, or half the diluted, concentration as may be found in the environment. The study demonstrated the important complementary roles of in vivo zebrafish and in vitro bioassays coupled with analytical chemistry in monitoring environmental glucocorticoid contaminants. Copyright © 2015 Elsevier Ltd. All rights reserved.

Environmental Management: the Ideology of Natural Resource Rational Use

NASA Astrophysics Data System (ADS)

Zolotukhin, V. M.; Gogolin, V. A.; Yazevich, M. Yu; Baumgarten, M. I.; Dyagileva, A. V.

2017-01-01

The article presents an analysis of the ontological and methodological principles of environmental management. These principles form the united ideology of natural resource rational use as the environment preservation basis. Consideration of environmental issues from the environmental management point of view is stipulated by the concern of the scientific community about the existence of mankind and the sphere of its inhabiting. The need to overcome the stereotypes existing in mass consciousness about safe and environmentally friendly consumption is stressed. The process of forming environmental management policy should contribute to the stabilization (balancing) of the consumers’ expectations and collective decision-making based on a public ecological consensus.

Lack of promotional effects of groundwater contaminant mixtures on the induction of preneoplastic foci in rat liver.

PubMed

Benjamin, S A; Yang, R S; Tessari, J D; Chubb, L W; Brown, M D; Dean, C E; Keefe, T J

1999-10-01

F344 rats were exposed to drinking water mixtures of seven of the most common groundwater contaminants associated with hazardous waste sites [arsenic, benzene, chloroform, chromium, lead, phenol, and trichloroethylene (TCE)] as the full mixture or submixtures of the organic and/or inorganic chemicals. The lowest concentrations (1x) of the individual chemicals were environmentally realistic and below what would be expected to induce significant short-term toxicity. This study was intended to determine if previously reported increases in localized hepatocellular proliferation in response to these chemicals might be correlated with increased risk for hepatocarcinogenesis. Rats were exposed via a drinking water solution to the full seven- chemical mixture (at 1x and 10x concentrations), submixtures of the organic or inorganic chemicals (at 10x concentrations), a mixture of TCE, lead, and chloroform (TLC submixture at 10x and 100x concentrations), or deionized water as a control. The rats were evaluated for promotion of placental glutathione-S-transferase (GST-P) positive preneoplastic liver cell foci after diethylnitrosamine (DEN) initiation and partial hepatectomy. Focus formation, cell proliferation, and apoptosis were evaluated after exposure to DEN or saline controls, the chemical mixtures or deionized water controls, or combinations of these treatments. The total number and area of GST-P positive foci in DEN-treated rats exposed to the full seven-chemical mixture was increased as compared with the DEN-water controls, but this was statistically significant only for total focus area in the 1x dose group. In DEN-treated rats, the inorganic or TLC submixtures resulted in a significant reduction in number and area of GST-P positive foci. Focus area also was decreased in the organic submixture-treated group, but not significantly. Hepatocellular proliferation was not significantly changed in the chemical mixture saline groups as compared with the mixture water controls. After DEN treatment, however, cell proliferation was significantly decreased after the 10x seven-chemical and organic mixture treatments and the 100x TLC mixture treatment. Different groups showed either increased or decreased apoptotic rates which did not correlate well with proliferation rates or focus formation. Mixtures of these seven chemicals, therefore, did not appear to act as promoters of hepatic foci at environmentally relevant concentrations, and some mixture combinations appeared to decrease promotional activity.

Potential risk of acute toxicity induced by AgI cloud seeding on soil and freshwater biota.

PubMed

Fajardo, C; Costa, G; Ortiz, L T; Nande, M; Rodríguez-Membibre, M L; Martín, M; Sánchez-Fortún, S

2016-11-01

Silver iodide is one of the most common nucleating materials used in cloud seeding. Previous cloud seeding studies have concluded that AgI is not practically bioavailable in the environment but instead remains in soils and sediments such that the free Ag amounts are likely too low to induce a toxicological effect. However, none of these studies has considered the continued use of this practice on the same geographical areas and thus the potential cumulative effect of environmental AgI. The aim of this study is to assess the risk of acute toxicity caused by AgI exposure under laboratory conditions at the concentration expected in the environment after repeated treatments on selected soil and aquatic biota. To achieve the aims, the viability of soil bacteria Bacillus cereus and Pseudomonas stutzeri and the survival of the nematode Caenorhabditis elegans exposed to different silver iodide concentrations have been evaluated. Freshwater green algae Dictyosphaerium chlorelloides and cyanobacteria Microcystis aeruginosa were exposed to silver iodide in culture medium, and their cell viability and photosynthetic activity were evaluated. Additionally, BOD5 exertion and the Microtox® toxicity test were included in the battery of toxicological assays. Both tests exhibited a moderate AgI adverse effect at the highest concentration (12.5µM) tested. However, AgI concentrations below 2.5µM increased BOD5. Although no impact on the growth and survival endpoints in the soil worm C. elegans was recorded after AgI exposures, a moderate decrease in cell viability was found for both of the assessed soil bacterial strains at the studied concentrations. Comparison between the studied species showed that the cyanobacteria were more sensitive than green algae. Exposure to AgI at 0.43μM, the reference value used in monitoring environmental impact, induced a significant decrease in photosynthetic activity that is primarily associated with the respiration (80% inhibition) and, to a lesser extent, the net photosynthesis (40% inhibition) in both strains of phytoplankton and a moderate decrease in soil bacteria viability. These results suggest that AgI from cloud seeding may moderately affect biota living in both terrestrial and aquatic ecosystems if cloud seeding is repeatedly applied in a specific area and large amounts of seeding materials accumulate in the environment. Copyright © 2016 Elsevier Inc. All rights reserved.

Single-provenance mature conifers show higher non-structural carbohydrate storage and reduced growth in a drier location.

PubMed

Piper, Frida I; Fajardo, Alex; Hoch, Günter

2017-08-01

Since growth is more sensitive to drought than photosynthesis, trees inhabiting dry regions are expected to exhibit higher carbohydrate storage and less growth than their conspecifics from more humid regions. However, the same pattern can be the result of different genotypes inhabiting contrasting humidity conditions. To test if reduced growth and high carbohydrate storage are environmentally driven by drought, we examined the growth and non-structural carbohydrate (NSC) concentrations in single-provenance stands of mature trees of Pinus contorta Douglas and Pinus ponderosa Douglas ex C. Lawson planted at contrasting humidity conditions (900 versus 300 mm of annual precipitation) in Patagonia, Chile. Individual tree growth was measured for each species and at each location as mean basal area increment of the last 10 years (BAI10), annual shoot elongation for the period 2011-14, and needle length for 2013 and 2014 cohorts. Additionally, needle, branch, stem sapwood and roots were collected from each sampled tree to determine soluble sugars, starch and total NSC concentrations. The two species showed lower mean BAI10 and 2013 needle length in the dry site; P. ponderosa also had lower annual shoot extension for 2011 and 2014, and lower 2014 needle length, in the dry than in the mesic site. By contrast, NSC concentrations of all woody tissues for both species were either similar or higher in the dry site when compared with the mesic site. Patterns of starch and sugars were substantially different: starch concentrations were similar between sites except for roots of P. ponderosa, which were higher in the dry site, while sugar concentrations of all woody tissues in both species were higher in the dry site. Overall, our study provides evidence that reduced growth along with carbon (C) accumulation is an environmentally driven response to drought. Furthermore, the significant accumulation of low-molecular weight sugars in the dry site is compatible with a prioritized C allocation for osmoregulation. However, since this accumulation did not come at the expense of reduced starch, it is unlikely that growth was limited by C supply in the dry site. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Validation of two dilution models to predict chloramine-T concentrations in aquaculture facility effluent

USGS Publications Warehouse

Gaikowski, M.P.; Larson, W.J.; Steuer, J.J.; Gingerich, W.H.

2004-01-01

Accurate estimates of drug concentrations in hatchery effluent are critical to assess the environmental risk of hatchery drug discharge resulting from disease treatment. This study validated two dilution simple n models to estimate chloramine-T environmental introduction concentrations by comparing measured and predicted chloramine-T concentrations using the US Geological Survey's Upper Midwest Environmental Sciences Center aquaculture facility effluent as an example. The hydraulic characteristics of our treated raceway and effluent and the accuracy of our water flow rate measurements were confirmed with the marker dye rhodamine WT. We also used the rhodamine WT data to develop dilution models that would (1) estimate the chloramine-T concentration at a given time and location in the effluent system and (2) estimate the average chloramine-T concentration at a given location over the entire discharge period. To test our models, we predicted the chloramine-T concentration at two sample points based on effluent flow and the maintenance of chloramine-T at 20 mg/l for 60 min in the same raceway used with rhodamine WT. The effluent sample points selected (sample points A and B) represented 47 and 100% of the total effluent flow, respectively. Sample point B is-analogous to the discharge of a hatchery that does not have a detention lagoon, i.e. The sample site was downstream of the last dilution water addition following treatment. We then applied four chloramine-T flow-through treatments at 20mg/l for 60 min and measured the chloramine-T concentration in water samples collected every 15 min for about 180 min from the treated raceway and sample points A and B during and after application. The predicted chloramine-T concentration at each sampling interval was similar to the measured chloramine-T concentration at sample points A and B and was generally bounded by the measured 90% confidence intervals. The predicted aver,age chloramine-T concentrations at sample points A or B (2.8 and 1.3 mg/l, respectively) were not significantly different (P > 0.05) from the average measured chloramine-T concentrations (2.7 and 1.3 mg/l, respectively). The close agreement between our predicted and measured chloramine-T concentrations indicate either of the dilution models could be used to adequately predict the chloramine-T environmental introduction concentration in Upper Midwest Environmental Sciences Center effluent. (C) 2003 Elsevier B.V. All rights reserved.

Purification and Concentration of Nanoparticles Using Diafiltration: Scientific Operating Procedure Series: SOP-P-1

DTIC Science & Technology

2015-07-01

Coupled Plasma Mass Spectroscopy (ICP-MS) analysis If the nanoparticle of choice is a metal such as gold or silver , an aliquot can be measured using USEPA...ER D C/ EL S R- 15 -4 Environmental Consequences of Nanotechnologies Purification and Concentration of Nanoparticles Using...Environmental Consequences of Nanotechnologies ERDC/EL SR-15-4 July 2015 Purification and Concentration of Nanoparticles Using Diafiltration

Participant-based monitoring of indoor and outdoor nitrogen dioxide, volatile organic compounds, and polycyclic aromatic hydrocarbons among MICA-Air households

NASA Astrophysics Data System (ADS)

Johnson, Markey M.; Williams, Ron; Fan, Zhihua; Lin, Lin; Hudgens, Edward; Gallagher, Jane; Vette, Alan; Neas, Lucas; Özkaynak, Halûk

2010-12-01

The Mechanistic Indicators of Childhood Asthma (MICA) study in Detroit, Michigan introduced a participant-based approach to reduce the resource burden associated with collection of indoor and outdoor residential air sampling data. A subset of participants designated as MICA-Air conducted indoor and outdoor residential sampling of nitrogen dioxide (NO 2), volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). This participant-based methodology was subsequently adapted for use in the Vanguard phase of the U.S. National Children's Study. The current paper examines residential indoor and outdoor concentrations of these pollutant species among health study participants in Detroit, Michigan. Pollutants measured under MICA-Air agreed well with other studies and continuous monitoring data collected in Detroit. For example, NO 2 and BTEX concentrations reported for other Detroit area monitoring were generally within 10-15% of indoor and outdoor concentrations measured in MICA-Air households. Outdoor NO 2 concentrations were typically higher than indoor NO 2 concentration among MICA-Air homes, with a median indoor/outdoor (I/O) ratio of 0.6 in homes that were not impacted by environmental tobacco smoke (ETS) during air sampling. Indoor concentrations generally exceeded outdoor concentrations for VOC and PAH species measured among non-ETS homes in the study. I/O ratios for BTEX species (benzene, toluene, ethylbenzene, and m/p- and o-xylene) ranged from 1.2 for benzene to 3.1 for toluene. Outdoor NO 2 concentrations were approximately 4.5 ppb higher on weekdays versus weekends. As expected, I/O ratios pollutants were generally higher for homes impacted by ETS. These findings suggest that participant-based air sampling can provide a cost-effective alternative to technician-based approaches for assessing indoor and outdoor residential air pollution in community health studies. We also introduced a technique for estimating daily concentrations at each home by weighting 2- and 7-day integrated concentrations using continuous measurements from regulatory monitoring sites. This approach may be applied to estimate short-term daily or hourly pollutant concentrations in future health studies.

Biodiversity increases functional and compositional resistance, but decreases resilience in phytoplankton communities.

PubMed

Baert, Jan M; De Laender, Frederik; Sabbe, Koen; Janssen, Colin R

2016-12-01

There is now ample evidence that biodiversity stabilizes aggregated ecosystem functions, such as primary production, in changing environments. In primary producer systems, this stabilizing effect is found to be driven by higher functional resistance (i.e., reduced changes in functions by environmental changes) rather than through higher functional resilience (i.e., rapid recovery following environmental changes) in more diverse systems. The stability of aggregated ecosystem functions directly depends on changes in species composition and by consequence their functional contributions to ecosystem functions. Still, it remains only theoretically explored how biodiversity can stabilize ecosystem functions by affecting compositional stability. Here, we demonstrate how biodiversity effects on compositional stability drive biodiversity effects on functional stability in diatom communities. In a microcosm experiment, we exposed 39 communities of five different levels of species richness (1, 2, 4, 6, and 8 species) to three concentrations of a chemical stressor (0, 25, and 250 μg/L atrazine) for four weeks, after which all communities were transferred to atrazine-free medium for three more weeks. Biodiversity simultaneously increased, increasing functional and compositional resistance, but decreased functional and compositional resilience. These results confirm the theoretically proposed link between biodiversity effects on functional and compositional stability in primary producer systems, and provide a mechanistic underpinning for observed biodiversity-stability relationships. Finally, we discuss how higher compositional stability can be expected to become increasingly important in stabilizing ecosystem functions under field conditions when multiple environmental stressors fluctuate simultaneously. © 2016 by the Ecological Society of America.

Fingerprinting the impacts of global change on tropical forests.

PubMed

Lewis, Simon L; Malhi, Yadvinder; Phillips, Oliver L

2004-03-29

Recent observations of widespread changes in mature tropical forests such as increasing tree growth, recruitment and mortality rates and increasing above-ground biomass suggest that 'global change' agents may be causing predictable changes in tropical forests. However, consensus over both the robustness of these changes and the environmental drivers that may be causing them is yet to emerge. This paper focuses on the second part of this debate. We review (i) the evidence that the physical, chemical and biological environment that tropical trees grow in has been altered over recent decades across large areas of the tropics, and (ii) the theoretical, experimental and observational evidence regarding the most likely effects of each of these changes on tropical forests. Ten potential widespread drivers of environmental change were identified: temperature, precipitation, solar radiation, climatic extremes (including El Niño-Southern Oscillation events), atmospheric CO2 concentrations, nutrient deposition, O3/acid depositions, hunting, land-use change and increasing liana numbers. We note that each of these environmental changes is expected to leave a unique 'fingerprint' in tropical forests, as drivers directly force different processes, have different distributions in space and time and may affect some forests more than others (e.g. depending on soil fertility). Thus, in the third part of the paper we present testable a priori predictions of forest responses to assist ecologists in attributing particular changes in forests to particular causes across multiple datasets. Finally, we discuss how these drivers may change in the future and the possible consequences for tropical forests.

Insights into discriminating environmental quality status using taxonomic distinctness based on a small species pool of ciliated protozoa in marine ecosystems.

PubMed

Jiang, Yong; Xu, Henglong; Warren, Alan

2014-01-15

The objective of this study was to determine the feasibility of developing a protocol for assessing marine water quality based on taxonomic relatedness within a small pool of planktonic ciliates. An annual dataset was compiled based on samples collected biweekly at five sites, with a gradient of environmental stress, during a 1-year cycle in Jiaozhou Bay, northern China. A total of 60 species, belonging to 17 genera 10 families, 5 orders and 2 classes of the phylum Ciliophora, were identified. Among five orders, Tintinnida showed a low variability mainly at species level whereas the other orders (especially Strombidiida and Choreotrichida, although with the exception of the genus Strombidium) represented a high variability at higher taxonomic ranks (e.g. family or order). Mantel analyses showed that spatial patterns of the ciliate assemblages, with tinitinnids and Strombidium spp. excluded, were significantly correlated with those of the total planktonic ciliate communities in terms of their response to environmental status. The average taxonomic distinctness (Δ(+)) based on the small species pool was significantly negatively correlated with the changes in concentrations of nutrients (P<0.05). Furthermore, the paired indices of Δ(+) and the variation in taxonomic distinctness (Λ(+)) showed a clear departure from the expected taxonomic pattern. These findings suggest that it is possible to assess the status of marine water quality using the taxonomic relatedness within a small pool of planktonic ciliates. © 2013.

Estimating environmental conditions affecting protozoal pathogen removal in surface water wetland systems using a multi-scale, model-based approach.

PubMed

Daniels, Miles E; Hogan, Jennifer; Smith, Woutrina A; Oates, Stori C; Miller, Melissa A; Hardin, Dane; Shapiro, Karen; Los Huertos, Marc; Conrad, Patricia A; Dominik, Clare; Watson, Fred G R

2014-09-15

Cryptosporidium parvum, Giardia lamblia, and Toxoplasma gondii are waterborne protozoal pathogens distributed worldwide and empirical evidence suggests that wetlands reduce the concentrations of these pathogens under certain environmental conditions. The goal of this study was to evaluate how protozoal removal in surface water is affected by the water temperature, turbidity, salinity, and vegetation cover of wetlands in the Monterey Bay region of California. To examine how protozoal removal was affected by these environmental factors, we conducted observational experiments at three primary spatial scales: settling columns, recirculating wetland mesocosm tanks, and an experimental research wetland (Molera Wetland). Simultaneously, we developed a protozoal transport model for surface water to simulate the settling columns, the mesocosm tanks, and the Molera Wetland. With a high degree of uncertainty expected in the model predictions and field observations, we developed the model within a Bayesian statistical framework. We found protozoal removal increased when water flowed through vegetation, and with higher levels of turbidity, salinity, and temperature. Protozoal removal in surface water was maximized (~0.1 hour(-1)) when flowing through emergent vegetation at 2% cover, and with a vegetation contact time of ~30 minutes compared to the effects of temperature, salinity, and turbidity. Our studies revealed that an increase in vegetated wetland area, with water moving through vegetation, would likely improve regional water quality through the reduction of fecal protozoal pathogen loads. Copyright © 2014 Elsevier B.V. All rights reserved.

Radionuclides, Metals, and Hydrocarbons in Oil and Gas Operational Discharges and Environmental Samples Associated with Offshore Production Facilities on the Texas/Louisiana Continental Shelf with an Environmental Assessment of Metals and Hydrocarbons.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-06-01

This report presents concentrations of radionuclides, metals, and hydrocarbons in samples of produced water and produced sand from oil and gas production platforms located offshore Texas and Louisiana. concentrations in produced water discharge plume / receiving water, ambient seawater, sediment, interstitial water, and marine animal tissue samples collected in the vicinity of discharging platforms and reference sites distant from discharges are also reported and discussed. An environmental risk assessment is made on the basis of the concentration of metals and hydrocarbons determined in the samples.

Radionuclides, Metals, and Hydrocarbons in Oil and Gas Operational Discharges and Environmental Samples Associated with Offshore Production Facilities on the Texas/Louisiana Continental Shelf with an Environmental Assessment of Metals and Hydrocarbons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Continental Shelf Associates, Inc.

1999-08-16

This report presents concentrations of radionuclides, metals, and hydrocarbons in samples of produced water and produced sand from oil and gas production platforms located offshore Texas and Louisiana. Concentrations in produced water discharge plume/receiving water, ambient seawater, sediment, interstitial water, and marine animal tissue samples collected in the vicinity of discharging platforms and reference sites distant from discharges are also reported and discussed. An environmental risk assessment is made on the basis of the concentrations of metals and hydrocarbons determined in the samples.

Real-world automotive particulate matter and PAH emission factors and profile concentrations: Results from an urban tunnel experiment in Naples, Italy

NASA Astrophysics Data System (ADS)

Riccio, A.; Chianese, E.; Monaco, D.; Costagliola, M. A.; Perretta, G.; Prati, M. V.; Agrillo, G.; Esposito, A.; Gasbarra, D.; Shindler, L.; Brusasca, G.; Nanni, A.; Pozzi, C.; Magliulo, V.

2016-09-01

On-road particulate matter (PM) mass was measured during a sampling campaign in March of 2015 in the '4 giornate' tunnel in Naples, Italy. Two sets of samples were collected at both sides of the tunnel, each set representing the daily cycle at a 1 h time resolution. Distance-based - mass per kilometer - and fuel-based - mass per burned fuel - emission factors (EFs) were calculated using mass concentrations, traffic flow rates and wind speed as a function of fleet composition. Also, chemical analyses were performed for polycyclic aromatic hydrocarbons (PAHs). Due to the high traffic volume, particle mass concentration at the tunnel exit was always significantly elevated relative to entrance concentration; depending on the hour of the day, PM10 concentration ranged between 300 μg/m3, during the early afternoon, and 600 μg/m3 during rush hours at the tunnel exit. Correspondingly, PAHs achieved concentrations as high as 1450 ng/m3, and benzo(a)pyrene, a surely carcinogenic compound, achieved concentrations as high as 69 ng/m3, raising serious concerns in relation to population exposure close to this urban tunnel. Distance-based and fuel-based emission factors for CO2, PM10 and PAHs were estimated, but while the EF for CO2 was within the range of expected values, the present study found much higher EFs for particulate matter and PAHs. According to the national official statistics from ISPRA (the Italian Institute for the Protection and Research on Environment), derived from the COPERT database, we expected an EF for particulate matter of about 55 mg/km, but the EF estimated from measurements taken at both sides of the tunnel was about four times higher than that expected; also, benzo(a)pyrene achieved an average EF of 2.7 μg/km, about three times higher than that expected from the ISPRA database.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hinwood, A.L., E-mail: a.hinwood@ecu.edu.au; Callan, A.C.; Ramalingam, M.

Recent literature suggests that exposure to low concentrations of heavy metals may affect both maternal and child health. This study aimed to determine the biological heavy metals concentrations of pregnant women as well as environmental and dietary factors that may influence exposure concentrations. One hundred and seventy three pregnant women were recruited from Western Australia, each providing a sample of blood, first morning void urine, residential soil, dust and drinking water samples. Participants also completed a questionnaire which included a food frequency component. All biological and environmental samples were analysed for heavy metals using ICP-MS. Biological and environmental concentrations ofmore » lead and mercury were generally low (Median Pb Drinking Water (DW) 0.04 µg/L; Pb soil <3.0 µg/g; Pb dust 16.5 µg/g; Pb blood 3.67 µg/L; Pb urine 0.55; µg/L Hg DW <0.03; Hg soil <1.0 µg/g; Hg dust <1.0 µg/g; Hg blood 0.46 µg/L; Hg urine <0.40 µg/L). Cadmium concentrations were low in environmental samples (Median CdDW 0.02 µg/L; Cdsoil <0.30 ug/g; Cddust <0.30) but elevated in urine samples (Median 0.55 µg/L, creatinine corrected 0.70 µg/g (range <0.2–7.06 µg/g creatinine) compared with other studies of pregnant women. Predictors of increased biological metals concentrations in regression models for blood cadmium were residing in the Great Southern region of Western Australia and not using iron/folic acid supplements and for urinary cadmium was having lower household annual income. However, these factors explained little of the variation in respective biological metals concentrations. The importance of establishing factors that influence low human exposure concentrations is becoming critical in efforts to reduce exposures and hence the potential for adverse health effects. -- Highlights: • Biological heavy metals concentrations in women in their 3rd trimester of pregnancy. • Exposure assessment including environmental, lifestyle and activity data. • Urinary cadmium concentrations were elevated in this group of pregnant women. • Blood lead and mercury concentrations were below recommended biological guideline values.« less

Dissolved oxygen, stream temperature, and fish habitat response to environmental water purchases.

PubMed

Null, Sarah E; Mouzon, Nathaniel R; Elmore, Logan R

2017-07-15

Environmental water purchases are increasingly used for ecological protection. In Nevada's Walker Basin (western USA), environmental water purchases augment streamflow in the Walker River and increase lake elevation of terminal Walker Lake. However, water quality impairments like elevated stream temperatures and low dissolved oxygen concentrations also limit ecosystems and species, including federally-threatened Lahontan cutthroat trout. In this paper, we prioritize water volumes and locations that most enhance water quality for riverine habitat from potential environmental water rights purchases. We monitored and modeled streamflows, stream temperatures, and dissolved oxygen concentrations using River Modeling System, an hourly, physically-based hydrodynamic and water quality model. Modeled environmental water purchases ranged from average daily increases of 0.11-1.41 cubic meters per second (m 3 /s) during 2014 and 2015, two critically dry years. Results suggest that water purchases consistently cooled maximum daily stream temperatures and warmed nightly minimum temperatures. This prevented extremely low dissolved oxygen concentrations below 5.0 mg/L, but increased the duration of moderate conditions between 5.5 and 6.0 mg/L. Small water purchases less than approximately 0.71 m 3 /s per day had little benefit for Walker River habitat. Dissolved oxygen concentrations were affected by upstream environmental conditions, where suitable upstream water quality improved downstream conditions and vice versa. Overall, this study showed that critically dry water years degrade environmental water quality and habitat, but environmental water purchases of at least 0.71 m 3 /s were promising for river restoration. Published by Elsevier Ltd.

Analysis of environmental dispersion in a wetland flow under the effect of wind: Extended solution

NASA Astrophysics Data System (ADS)

Wang, Huilin; Huai, Wenxin

2018-02-01

The accurate analysis of the contaminant transport process in wetland flows is essential for environmental assessment. However, dispersivity assessment becomes complicated when the wind strength and direction are taken into consideration. Prior studies illustrating the wind effect on environmental dispersion in wetland flows simply focused on the mean longitudinal concentration distribution. Moreover, the results obtained by these analyses are not accurate when done on a smaller scale, namely, the initial stage of the contaminant transport process. By combining the concentration moments method (the Aris' method) and Gill's expansion theory, the previous researches on environmental dispersion in wetland flows with effect of wind have been extended. By adopting up to 4th-order moments, the wind effect-as illustrated by dimensionless parameters Er (wind force) and ω (wind direction)-on kurtosis and skewness is discussed, the up to 4th-order vertical concentration distribution is obtained, and the two-dimensional concentration distribution is illustrated. This work demonstrates that wind intensity and direction can significantly affect the contaminant dispersion. Moreover, the study presents a more accurate analytical solution of environmental dispersion in wetland flows under various wind conditions.

Challenges for environmental epidemiology research: are biomarker concentrations altered by kidney function or urine concentration adjustment?

EPA Science Inventory

Biological monitoring has become a standard approach to exposure assessment in occupational and environmental epidemiology. The use of biological effect markers to identify early adverse changes in target organs has also become widely adopted. Recently, nephrotoxicant research us...

Transport of Fluorescently Labeled Hydroxyapatite Nanoparticles in Saturated Granular Media at Environmentally Relevant Concentrations of Surfactants

EPA Science Inventory

Little is known about the mobility of engineered nanoparticles (ENPs) in granular media at environmentally relevant concentration of surfactant, which represents a critical knowledge gap in employing ENPs for in-situ remediation of contaminated groundwater. In this study, transpo...

Assessment of 17{alpha}-ethinylestradiol effects and underlying mechanisms in a continuous, multigeneration exposure of the Chinese rare minnow (Gobiocypris rarus)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zha Jinmiao; Sun Liwei; Zhou Yiqi

17{alpha}-Ethinylestradiol (EE{sub 2}) is a synthetic estrogen used primarily in birth control pills and in hormone replacement therapy. Owing to its occurrence in surface waters at concentrations frequently greater than 1 ng/l and its projected future use, EE{sub 2} is expected to pose a significant risk to aquatic organisms. This study was conducted to obtain long-term exposure data necessary for the establishment of water quality criteria and to investigate mechanisms associated with toxic effects. In a multigeneration experiment, Chinese rare minnows (Gobiocypris rarus) were constantly exposed to environmentally relevant concentrations of the synthetic estrogen EE{sub 2}. Mortality, deformities, reproductive parameters,more » plasma vitellogenin and histopathology were assessed. The results showed that, in the F{sub 0} generation, all endpoints were significantly affected at concentrations higher than 0.2 ng/l EE{sub 2}. No F{sub 1} phenotypic males developed to maturity at 0.2 ng/l and, when adult females of this exposure group were crossed with unexposed males, no F{sub 2} fertile eggs were produced. Kidney histopathology and ultrastructure suggest anomalies possibly associated with increased vitellogenin accumulation. We concluded that the reproduction of the F{sub 1} minnows was completely inhibited at the lowest concentration tested, 0.2 ng/l EE{sub 2}, a concentration frequently detected in surface waters. Growth effects may be related to increased energy requirements including the energy used in VTG synthesis. Reproductive effects are presumably associated with male feminization and the occurrence of testis-ova in males; however, ovarian degeneration observed in females may also have contributed to reproductive failure.« less

The consequences of exposure to mixtures of chemicals: Something from 'nothing' and 'a lot from a little' when fish are exposed to steroid hormones.

PubMed

Thrupp, Tara J; Runnalls, Tamsin J; Scholze, Martin; Kugathas, Subramaniam; Kortenkamp, Andreas; Sumpter, John P

2018-04-01

Ill-defined, multi-component mixtures of steroidal pharmaceuticals are present in the aquatic environment. Fish are extremely sensitive to some of these steroids. It is important to know how fish respond to these mixtures, and from that knowledge develop methodology that enables accurate prediction of those responses. To provide some of the data required to reach this objective, pairs of fish were first exposed to five different synthetic steroidal pharmaceuticals (one estrogen, EE2; one androgen, trenbolone; one glucocorticoid, beclomethasone dipropionate; and two progestogens, desogestrel and levonorgestrel) and concentration-response data on egg production obtained. Based on those concentration-response relationships, a five component mixture was designed and tested twice. Very similar effects were observed in the two experiments. The mixture inhibited egg production in an additive manner predicted better by the model of Independent Action than that of Concentration Addition. Our data provide a reference case for independent action in an in vivo model. A significant combined effect was observed when each steroidal pharmaceutical in the mixture was present at a concentration which on its own would produce no statistically significant effect (something from 'nothing'). Further, when each component was present in the mixture at a concentration expected to inhibit egg production by between 18% (Beclomethasone diproprionate) and 40% (trenbolone), this mixture almost completely inhibited egg production: a phenomenon we term 'a lot from a little'. The results from this proof-of-principle study suggest that multiple steroids present in the aquatic environment can be analysed for their potential combined environmental risk. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Assessment of bioavailability of soil-sorbed atrazine.

PubMed

Park, Jeong-Hun; Feng, Yucheng; Ji, Pingsheng; Voice, Thomas C; Boyd, Stephen A

2003-06-01

Bioavailability of pesticides sorbed to soils is an important determinant of their environmental fate and impact. Mineralization of sorbed atrazine was studied in soil and clay slurries, and a desorption-biodegradation-mineralization (DBM) model was developed to quantitatively evaluate the bioavailability of sorbed atrazine. Three atrazine-degrading bacteria that utilized atrazine as a sole N source (Pseudomonas sp. strain ADP, Agrobacterium radiobacter strain J14a, and Ralstonia sp. strain M91-3) were used in the bioavailability assays. Assays involved establishing sorption equilibrium in sterile soil slurries, inoculating the system with organisms, and measuring the CO(2) production over time. Sorption and desorption isotherm analyses were performed to evaluate distribution coefficients and desorption parameters, which consisted of three desorption site fractions and desorption rate coefficients. Atrazine sorption isotherms were linear for mineral and organic soils but displayed some nonlinearity for K-saturated montmorillonite. The desorption profiles were well described by the three-site desorption model. In many instances, the mineralization of atrazine was accurately predicted by the DBM model, which accounts for the extents and rates of sorption/desorption processes and assumes biodegradation of liquid-phase, but not sorbed, atrazine. However, for the Houghton muck soil, which manifested the highest sorbed atrazine concentrations, enhanced mineralization rates, i.e., greater than those expected on the basis of aqueous-phase atrazine concentration, were observed. Even the assumption of instantaneous desorption could not account for the elevated rates. A plausible explanation for enhanced bioavailability is that bacteria access the localized regions where atrazine is sorbed and that the concentrations found support higher mineralization rates than predicted on the basis of aqueous-phase concentrations. Characteristics of high sorbed-phase concentration, chemotaxis, and attachment of cells to soil particles seem to contribute to the bioavailability of soil-sorbed atrazine.

Assessment of Bioavailability of Soil-Sorbed Atrazine

PubMed Central

Park, Jeong-Hun; Feng, Yucheng; Ji, Pingsheng; Voice, Thomas C.; Boyd, Stephen A.

2003-01-01

Bioavailability of pesticides sorbed to soils is an important determinant of their environmental fate and impact. Mineralization of sorbed atrazine was studied in soil and clay slurries, and a desorption-biodegradation-mineralization (DBM) model was developed to quantitatively evaluate the bioavailability of sorbed atrazine. Three atrazine-degrading bacteria that utilized atrazine as a sole N source (Pseudomonas sp. strain ADP, Agrobacterium radiobacter strain J14a, and Ralstonia sp. strain M91-3) were used in the bioavailability assays. Assays involved establishing sorption equilibrium in sterile soil slurries, inoculating the system with organisms, and measuring the CO2 production over time. Sorption and desorption isotherm analyses were performed to evaluate distribution coefficients and desorption parameters, which consisted of three desorption site fractions and desorption rate coefficients. Atrazine sorption isotherms were linear for mineral and organic soils but displayed some nonlinearity for K-saturated montmorillonite. The desorption profiles were well described by the three-site desorption model. In many instances, the mineralization of atrazine was accurately predicted by the DBM model, which accounts for the extents and rates of sorption/desorption processes and assumes biodegradation of liquid-phase, but not sorbed, atrazine. However, for the Houghton muck soil, which manifested the highest sorbed atrazine concentrations, enhanced mineralization rates, i.e., greater than those expected on the basis of aqueous-phase atrazine concentration, were observed. Even the assumption of instantaneous desorption could not account for the elevated rates. A plausible explanation for enhanced bioavailability is that bacteria access the localized regions where atrazine is sorbed and that the concentrations found support higher mineralization rates than predicted on the basis of aqueous-phase concentrations. Characteristics of high sorbed-phase concentration, chemotaxis, and attachment of cells to soil particles seem to contribute to the bioavailability of soil-sorbed atrazine. PMID:12788728

Shedding light on the paradox of high alkaline phosphatase utilization at high end-product concentrations

NASA Astrophysics Data System (ADS)

Baltar, F.; Lundin, D.; Palovaara, J.; Reinthaler, T.; Herndl, G. J.; Pinhassi, J.

2016-02-01

Alkaline phosphatase (APase) activity is supposed to be regulated by the concentration of its endproduct, decreasing with increasing inorganic phosphate (Pi) concentrations. Since Pi is readily available in the deep ocean, APase activity would be expected to be low. However, high APase activities at high Pi concentrations have been found in the deep Indian and Atlantic Ocean. To understand how APase activities are regulated and what mechanisms are responsible for its regulation we performed microcosm experiments with mesopelagic North Atlantic waters. Treatments consisted of enrichment with either ammonium or organic carbon, and were compared to unamended controls. We assessed changes in prokaryotic abundance, APase, leucine aminopeptidase, heterotrophic production, dark CO2 fixation and community gene expression (metatranscriptomics) between treatments and control. In the organic matter enrichments, APase increased along with all measured rates, whereas only dark CO2 fixation and APase were enhanced in the ammonium enrichment. In the organic matter enrichment, genes for heterotrophic metabolism were strongly upregulated, whereas genes for ammonia oxidation and CO2 fixation were upregulated in the ammonium treatment. In both treatments, the Pho regulon -a global regulatory mechanism involved in bacterial Pi management- was also upregulated, including genes encoding alkaline phosphatases. The activation of the Pho regulon seemed to be related to cross-activation by nonpartner histidine kinases, and/or the activation of genes involved in the regulation of elemental balance during catabolic processes. Increased C or N bioavailability thus appear to elicit a Pi deficiency inside cells and activate the Pho regulon. These results indicate possible ways (e.g. pulses of C or N or changes in elemental ratios) in which APase can be activated irrespectively of the environmental Pi concentration.

Mercury concentration in meconium and risk assessment of fish consumption among pregnant women in Taiwan.

PubMed

Jiang, Chuen-Bin; Yeh, Ching-Ying; Lee, Hung-Chang; Chen, Ming-Jun; Hung, Fang-Yu; Fang, Sheng-Shiung; Chien, Ling-Chu

2010-01-01

Meconium is a matrix that can be obtained easily and noninvasively and is useful for detecting antenatal fetal exposure to environmental toxins. Taiwan is an island with high fish consumption, and many pregnant women would like to enjoy the benefits of fish without jeopardizing their health or that of their child. The aim of this study is to assess the mercury concentration in meconium in relation to the health risk of mercury exposure. A total of 198 mother-infant pairs residing in the city of HsinChu were recruited for the study between January 2007 and June 2007. The average mean concentration of mercury in meconium was 79.2+/-7.3 ng g(-1) dry wt We use the Monte Carlo technique to assess the uncertainty in risk assessment and the impact of these uncertainties on the estimation of expected risk of mercury intake from fish in mothers. Based on the FAO/WHO's tolerable daily intake of methylmercury (0.23 microg kg(-1)d(-1)), we found that 17.3% and 14.0% of the daily mercury exposure estimated exceeded the reference dose for foreign-born and Taiwan-born mothers, respectively. We found that the mercury concentration in meconium was much higher than in other studies, except for one study done in Tagum in the Philippines where mercury is used in gold mining. This may be because Asia is the largest emitter of anthropogenic mercury, accounting for 53% of worldwide emissions. Sensitivity analysis suggests that mercury concentration in fish and the rate of ingesting fish may be the key parameters for governments offering risk management guidance to protect the health of mothers and unborn babies.

Methylmercury bioaccumulation in an urban estuary: Delaware River USA.

PubMed

Buckman, Kate; Taylor, Vivien; Broadley, Hannah; Hocking, Daniel; Balcom, Prentiss; Mason, Rob; Nislow, Keith; Chen, Celia

2017-09-01

Spatial variation in mercury (Hg) and methylmercury (MeHg) bioaccumulation in urban coastal watersheds reflects complex interactions between Hg sources, land use, and environmental gradients. We examined MeHg concentrations in fauna from the Delaware River estuary, and related these measurements to environmental parameters and human impacts on the waterway. The sampling sites followed a north to south gradient of increasing salinity, decreasing urban influence, and increasing marsh cover. Although mean total Hg in surface sediments (top 4cm) peaked in the urban estuarine turbidity maximum and generally decreased downstream, surface sediment MeHg concentrations showed no spatial patterns consistent with the examined environmental gradients, indicating urban influence on Hg loading to the sediment but not subsequent methylation. Surface water particulate MeHg concentration showed a positive correlation with marsh cover whereas dissolved MeHg concentrations were slightly elevated in the estuarine turbidity maximum region. Spatial patterns of MeHg bioaccumulation in resident fauna varied across taxa. Small fish showed increased MeHg concentrations in the more urban/industrial sites upstream, with concentrations generally decreasing farther downstream. Invertebrates either showed no clear spatial patterns in MeHg concentrations (blue crabs, fiddler crabs) or increasing concentrations further downstream (grass shrimp). Best-supported linear mixed models relating tissue concentration to environmental variables reflected these complex patterns, with species specific model results dominated by random site effects with a combination of particulate MeHg and landscape variables influencing bioaccumulation in some species. The data strengthen accumulating evidence that bioaccumulation in estuaries can be decoupled from sediment MeHg concentration, and that drivers of MeHg production and fate may vary within a small region.

Niagara Falls Storage Site annual site environmental monitoring report. Calendar year 1985

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1986-04-01

During 1985, an environmental monitoring program was continued at the Niagara Falls Storage Site (NFSS), a United States Department of Energy (DOE) surplus facility located in Niagara County, New York, presently used for the interim storage of low-level radioactive residues and contaminated soils and rubble. The monitoring program is being conducted by Bechtel National, Inc. Monitoring results show that the NFSS is in compliance with DOE concentration guides and radiation protection standards. Derived Concentration Guides (DCGs) represent the concentrations of radionuclides in air or water that would limit the radiation dose to 100 mrem/yr. The applicable limits have been revisedmore » since the 1984 environmental monitoring report was published. The limits applied in 1984 were based on a radiation protection standard of 500 mrem/yr; the limits applied for the 1985 are based on a standard of 100 mrem/yr. To determine whether the site is in compliance with DOE standards, environmental measurements are expressed as percentages of the applicable DCG, while the calculated doses to the public are expressed as percentages of the applicable radiation protection standard. The monitoring program measured radon gas concentrations in air; uranium and radium concentrations in surface water, groundwater, and sediments; and external gamma dose rates. Environmental samples collected were analyzed to determine compliance with applicable standards. Potential radiation doses to the public were also calculated.« less

Effect of environmental setting on sediment, nitrogen, and phosphorus concentrations in Albemarle-Pamlico drainage basin, North Carolina and Virginia, USA

USGS Publications Warehouse

McMahon, G.; Harned, D.A.

1998-01-01

Environmental settings were defined, through an overlay process, as areas of coincidence between categories of three mapped variables - land use, surficial geology, and soil drainage characteristics. Expert judgment was used in selecting factors thought to influence sediment and nutrient concentrations in the Albemarle-Pamlico drainage area. This study's findings support the hypothesis that environmental settings defined using these three variables can explain variations in the concentration of certain sediment and nutrient constituents. This finding underscores the importance of developing watershed management plans that account for differences associated with the mosaic of natural and anthropogenic factors that define a basin's environmental setting. At least in the case of sediment and nutrients in the Albemarle-Pamlico region, a watershed management plan that focuses only on anthropogenic factors, such as point-source discharges, and does not account for natural characteristics of a watershed and the influences of these characteristics on water quality, may lead to water-quality goals that are over- or underprotective of key environmental features and to a misallocation of the resources available for environmental protection.

Niagara Falls Storage Site annual environmental report for calendar year 1991, Lewiston, New York. [Niagara Falls Storage Site

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-09-01

This document describes the environmental monitoring program at the Niagara Falls Storage Site (NFSS) and surrounding area, implementation of the program, and monitoring results for 1991. Environmental monitoring at NFSS began in 1981. The site is owned by the US Department of Energy (DOE) and is assigned to the DOE Formerly Utilized Sites Remedial Action Program (FUSRAP). FUSRAP is a program to decontaminate or otherwise control sites where residual radioactive materials remain from the early years of the nation's atomic energy program or from commercial operations causing conditions that Congress has authorized DOE to remedy. The environmental monitoring program atmore » NFSS includes sampling networks for radon concentrations in air; external gamma radiation exposure; and total uranium and radium-226 concentrations in surface water, sediments, and groundwater. Additionally, several nonradiological parameters including seven metals are routinely measured in groundwater. Monitoring results are compared with applicable Environmental Protection Agency (EPA) standards, DOE derived concentration guides (DCGs), dose limits, and other requirements in DOE orders. Environmental standards are established to protect public health and the environment.« less

Niagara Falls Storage Site annual environmental report for calendar year 1991, Lewiston, New York

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-09-01

This document describes the environmental monitoring program at the Niagara Falls Storage Site (NFSS) and surrounding area, implementation of the program, and monitoring results for 1991. Environmental monitoring at NFSS began in 1981. The site is owned by the US Department of Energy (DOE) and is assigned to the DOE Formerly Utilized Sites Remedial Action Program (FUSRAP). FUSRAP is a program to decontaminate or otherwise control sites where residual radioactive materials remain from the early years of the nation`s atomic energy program or from commercial operations causing conditions that Congress has authorized DOE to remedy. The environmental monitoring program atmore » NFSS includes sampling networks for radon concentrations in air; external gamma radiation exposure; and total uranium and radium-226 concentrations in surface water, sediments, and groundwater. Additionally, several nonradiological parameters including seven metals are routinely measured in groundwater. Monitoring results are compared with applicable Environmental Protection Agency (EPA) standards, DOE derived concentration guides (DCGs), dose limits, and other requirements in DOE orders. Environmental standards are established to protect public health and the environment.« less

Quality of water and sediment in streams affected by historical mining, and quality of Mine Tailings, in the Rio Grande/Rio Bravo Basin, Big Bend Area of the United States and Mexico, August 2002

USGS Publications Warehouse

Lambert, Rebecca B.; Kolbe, Christine M.; Belzer, Wayne

2008-01-01

The U.S. Geological Survey, in cooperation with the International Boundary and Water Commission - U.S. and Mexican Sections, the National Park Service, the Texas Commission on Environmental Quality, the Secretaria de Medio Ambiente y Recursos Naturales in Mexico, the Area de Proteccion de Flora y Fauna Canon de Santa Elena in Mexico, and the Area de Proteccion de Flora y Fauna Maderas del Carmen in Mexico, collected samples of stream water, streambed sediment, and mine tailings during August 2002 for a study to determine whether trace elements from abandoned mines in the area in and around Big Bend National Park have affected the water and sediment quality in the Rio Grande/Rio Bravo Basin of the United States and Mexico. Samples were collected from eight sites on the main stem of the Rio Grande/Rio Bravo, four Rio Grande/Rio Bravo tributary sites downstream from abandoned mines or mine-tailing sites, and 11 mine-tailing sites. Mines in the area were operated to produce fluorite, germanium, iron, lead, mercury, silver, and zinc during the late 1800s through at least the late 1970s. Moderate (relatively neutral) pHs in stream-water samples collected at the 12 Rio Grande/Rio Bravo main-stem and tributary sites indicate that water is well mixed, diluted, and buffered with respect to the solubility of trace elements. The highest sulfate concentrations were in water samples from tributaries draining the Terlingua mining district. Only the sample from the Rough Run Draw site exceeded the Texas Surface Water Quality Standards general-use protection criterion for sulfate. All chloride and dissolved solids concentrations in water samples were less than the general-use protection criteria. Aluminum, copper, mercury, nickel, selenium, and zinc were detected in all water samples for which each element was analyzed. Cadmium, chromium, and lead were detected in samples less frequently, and silver was not detected in any of the samples. None of the sample concentrations of aluminum, cadmium, chromium, nickel, selenium, and zinc exceeded the Texas Surface Water Quality Standards criteria for aquatic life-use protection or human health. The only trace elements detected in the water samples at concentrations exceeding the Texas Surface Water Quality Standards criterion for human health (fish consumption use) was lead at one site and mercury at 10 of 12 sites. Relatively high mercury concentrations distributed throughout the area might indicate sources of mercury in addition to abandoned mining areas. Streambed-sediment samples were collected from 12 sites and analyzed for 44 major and trace elements. In general, the trace elements detected in streambed-sediment samples were low in concentration, interpreted as consistent with background concentrations. Concentrations at two sites, however, were elevated compared to Texas Commission on Environmental Quality criteria. Concentrations of antimony, arsenic, cadmium, lead, silver, and zinc in the sample from San Carlos Creek downstream from La Esperanza (San Carlos) Mine exceeded the Texas Commission on Environmental Quality screening levels for sediment. The sample from Rough Run Draw, downstream from the Study Butte Mine, also showed elevated concentrations of arsenic, cadmium, and lead, but these concentrations were much lower than those in the San Carlos Creek sample and did not exceed screening levels. Elevated concentrations of multiple trace elements in streambed-sediment samples from San Carlos Creek and Rough Run Draw indicate that San Carlos Creek, and probably Rough Run Draw, have been adversely affected by mining activities. Fourteen mine-tailing samples from 11 mines were analyzed for 25 major and trace elements. All trace elements except selenium and thallium were detected in one or more samples. The highest lead concentrations were detected in tailings samples from the Boquillas, Puerto Rico, La Esperanza (San Carlos), and Tres Marias Mines, as might be expected because the tailings ar

Impaired growth in the polychaete Armandia brevis exposed to tributyltin in sediment.

PubMed

Meador, J P; Rice, C A

2001-03-01

Juveniles of the opheliid polychaete, Armandia brevis, were exposed to sediment-associated tributyltin (TBT) for 42 days to evaluate toxicity and bioaccumulation. Growth in this species was inhibited in a dose-response fashion by increasing concentrations of TBT. Even though the biota-sediment accumulation factor (BSAF) for TBT declined for the higher sediment concentrations, the total butyltins in tissue increased over all sediment concentrations. At the highest sediment concentrations, polychaetes bioaccumulated less TBT than expected, which was most likely due to reduced uptake and continued metabolism of the parent compound. The less than expected BSAF values exhibited by animals at the exposure concentrations causing severe effects are an important finding for assessing responses in the field. It appears that severe biological effects can occur in long-term experiments without the expected high tissue concentrations; an observation likely explained by altered toxicokinetics. Analysis of variance determined the lowest observed effect concentration for growth to be 191 ng/g sediment dry wt. for 21 days of exposure and 101 ng/g sediment dry wt. at day 42, indicating that 21 days was insufficient for delineating the steady-state toxicity response. When based on regression analysis, the sediment concentration causing a 25% inhibition in growth at 42 days exposure was 93 ng/g dry wt. (total organic carbon = 0.58%). A dose-response association was also determined for polychaete net weight and TBT in tissue. The tissue residue associated with a 25% reduction in growth was 2834 ng/g dry wt. at day 42. A comparison of these results with previous work indicates that juveniles are approximately three times more sensitive than adults to TBT exposure. The sediment concentrations affecting growth in this species are commonly found in urban waterways indicating potentially severe impacts for this and other sensitive species.

The Influence of Individual Variability on Zooplankton Population Dynamics under Different Environmental Conditions

NASA Astrophysics Data System (ADS)

Bi, R.; Liu, H.

2016-02-01

Understanding how biological components respond to environmental changes could be insightful to predict ecosystem trajectories under different climate scenarios. Zooplankton are key components of marine ecosystems and changes in their dynamics could have major impact on ecosystem structure. We developed an individual-based model of a common coastal calanoid copepod Acartia tonsa to examine how environmental factors affect zooplankton population dynamics and explore the role of individual variability in sustaining population under various environmental conditions consisting of temperature, food concentration and salinity. Total abundance, egg production and proportion of survival were used to measure population success. Results suggested population benefits from high level of individual variability under extreme environmental conditions including unfavorable temperature, salinity, as well as low food concentration, and selection on fast-growers becomes stronger with increasing individual variability and increasing environmental stress. Multiple regression analysis showed that temperature, food concentration, salinity and individual variability have significant effects on survival of A. tonsa population. These results suggest that environmental factors have great influence on zooplankton population, and individual variability has important implications for population survivability under unfavorable conditions. Given that marine ecosystems are at risk from drastic environmental changes, understanding how individual variability sustains populations could increase our capability to predict population dynamics in a changing environment.

7 CFR 1940.327 - Tiering.

Code of Federal Regulations, 2010 CFR

2010-01-01

... environmental assessments and EISs. Tiering refers to the coverage of general matters in broader environmental... statements or environmental analyses incorporating by reference the broader matters and concentrating on the...

7 CFR 1940.327 - Tiering.

Code of Federal Regulations, 2014 CFR

2014-01-01

... environmental assessments and EISs. Tiering refers to the coverage of general matters in broader environmental... statements or environmental analyses incorporating by reference the broader matters and concentrating on the...

7 CFR 1940.327 - Tiering.

Code of Federal Regulations, 2013 CFR

2013-01-01

... environmental assessments and EISs. Tiering refers to the coverage of general matters in broader environmental... statements or environmental analyses incorporating by reference the broader matters and concentrating on the...

7 CFR 1940.327 - Tiering.

Code of Federal Regulations, 2012 CFR

2012-01-01

... environmental assessments and EISs. Tiering refers to the coverage of general matters in broader environmental... statements or environmental analyses incorporating by reference the broader matters and concentrating on the...

7 CFR 1940.327 - Tiering.

Code of Federal Regulations, 2011 CFR

2011-01-01

... environmental assessments and EISs. Tiering refers to the coverage of general matters in broader environmental... statements or environmental analyses incorporating by reference the broader matters and concentrating on the...

Perceived Social Support and Locus of Control as the Predictors of Vocational Outcome Expectations

ERIC Educational Resources Information Center

Isik, Erkan

2013-01-01

The purpose of this study was to examine the relationships of vocational outcome expectation to social support which is an environmental factor and locus of control which is a personal factor. With this purpose, using Social Cognitive Career Theory as the theoretical framework, 263 undergraduate students completed Vocational Outcome Expectations…

Absolute quantification of Dehalococcoides proteins: enzyme bioindicators of chlorinated ethene dehalorespiration.

PubMed

Werner, Jeffrey J; Ptak, A Celeste; Rahm, Brian G; Zhang, Sheng; Richardson, Ruth E

2009-10-01

The quantification of trace proteins in complex environmental samples and mixed microbial communities would be a valuable monitoring tool in countless applications, including the bioremediation of groundwater contaminated with chlorinated solvents. Measuring the concentrations of specific proteins provides unique information about the activity and physiological state of organisms in a sample. We developed sensitive (< 5 fmol), selective bioindicator assays for the absolute quantification of select proteins used by Dehalococcoides spp. when reducing carbon atoms in the common pollutants trichloroethene (TCE) and tetrachloroethene (PCE). From complex whole-sample digests of two different dechlorinating mixed communities, we monitored the chromatographic peaks of selected tryptic peptides chosen to represent 19 specific Dehalococcoides proteins. This was accomplished using multiple-reaction monitoring (MRM) assays using nano-liquid chromatography-tandem mass spectrometry (nLC-MS/MS), which provided the selectivity, sensitivity and reproducibility required to quantify Dehalococcoides proteins in complex samples. We observed reproducible peak areas (average CV = 0.14 over 4 days, n = 3) and linear responses in standard curves (n = 5, R(2) > 0.98) using synthetic peptide standards spiked into a background matrix of sediment peptides. We detected and quantified TCE reductive dehalogenase (TceA) at 7.6 +/- 1.7 x 10(3) proteins cell(-1) in the KB1 bioaugmentation culture, previously thought to be lacking TceA. Fragmentation data from MS/MS shotgun proteomics experiments were helpful in developing the MRM targets. Similar shotgun proteomics data are emerging in labs around the world for many environmentally relevant microbial proteins, and these data are a valuable resource for the future development of MRM assays. We expect targeted peptide quantification in environmental samples to be a useful tool in environmental monitoring.

The future of hydropower planning modeling

NASA Astrophysics Data System (ADS)

Haas, J.; Zuñiga, D.; Nowak, W.; Olivares, M. A.; Castelletti, A.; Thilmant, A.

2017-12-01

Planning the investment and operation of hydropower plants with optimization tools dates back to the 1970s. The focus used to be solely on the provision of energy. However, advances in computational capacity and solving algorithms, dynamic markets, expansion of renewable sources, and a better understanding of hydropower environmental impacts have recently led to the development of novel planning approaches. In this work, we provide a review, systematization, and trend analysis of these approaches. Further, through interviews with experts, we outline the future of hydropower planning modeling and identify the gaps towards it. We classified the found models along environmental, economic, multipurpose and technical criteria. Environmental interactions include hydropeaking mitigation, water quality protection and limiting greenhouse gas emissions from reservoirs. Economic and regulatory criteria consider uncertainties of fossil fuel prices and relicensing of water rights and power purchase agreements. Multipurpose considerations account for irrigation, tourism, flood protection and drinking water. Recently included technical details account for sedimentation in reservoirs and variable efficiencies of turbines. Additional operational considerations relate to hydrological aspects such as dynamic reservoir inflows, water losses, and climate change. Although many of the above criteria have been addressed in detail on a project-to-project basis, models remain overly simplistic for planning large power fleets. Future hydropower planning tools are expected to improve the representation of the water-energy nexus, including environmental and multipurpose criteria. Further, they will concentrate on identifying new sources of operational flexibility (e.g. through installing additional turbines and pumps) for integrating renewable energy. The operational detail will increase, potentially emphasizing variable efficiencies, storage capacity losses due to sedimentation, and the timing of inflows (which are becoming more variable under climate change). Finally, the relicensing of existing operations and planning new installations are subject to deep uncertainties that need to be captured.

Potential effects of climate change on the distribution range of the main silicate sinker of the Southern Ocean.

PubMed

Pinkernell, Stefan; Beszteri, Bánk

2014-08-01

Fragilariopsis kerguelensis, a dominant diatom species throughout the Antarctic Circumpolar Current, is coined to be one of the main drivers of the biological silicate pump. Here, we study the distribution of this important species and expected consequences of climate change upon it, using correlative species distribution modeling and publicly available presence-only data. As experience with SDM is scarce for marine phytoplankton, this also serves as a pilot study for this organism group. We used the maximum entropy method to calculate distribution models for the diatom F. kerguelensis based on yearly and monthly environmental data (sea surface temperature, salinity, nitrate and silicate concentrations). Observation data were harvested from GBIF and the Global Diatom Database, and for further analyses also from the Hustedt Diatom Collection (BRM). The models were projected on current yearly and seasonal environmental data to study current distribution and its seasonality. Furthermore, we projected the seasonal model on future environmental data obtained from climate models for the year 2100. Projected on current yearly averaged environmental data, all models showed similar distribution patterns for F. kerguelensis. The monthly model showed seasonality, for example, a shift of the southern distribution boundary toward the north in the winter. Projections on future scenarios resulted in a moderately to negligibly shrinking distribution area and a change in seasonality. We found a substantial bias in the publicly available observation datasets, which could be reduced by additional observation records we obtained from the Hustedt Diatom Collection. Present-day distribution patterns inferred from the models coincided well with background knowledge and previous reports about F. kerguelensis distribution, showing that maximum entropy-based distribution models are suitable to map distribution patterns for oceanic planktonic organisms. Our scenario projections indicate moderate effects of climate change upon the biogeography of F. kerguelensis.

The Small Area Health Statistics Unit: a national facility for investigating health around point sources of environmental pollution in the United Kingdom.

PubMed Central

Elliott, P; Westlake, A J; Hills, M; Kleinschmidt, I; Rodrigues, L; McGale, P; Marshall, K; Rose, G

1992-01-01

STUDY OBJECTIVE--The Small Area Health Statistics Unit (SAHSU) was established at the London School of Hygiene and Tropical Medicine in response to a recommendation of the enquiry into the increased incidence of childhood leukaemia near Sellafield, the nuclear reprocessing plant in West Cumbria. The aim of this paper was to describe the Unit's methods for the investigation of health around point sources of environmental pollution in the United Kingdom. DESIGN--Routine data currently including deaths and cancer registrations are held in a large national database which uses a post code based retrieval system to locate cases geographically and link them to the underlying census enumeration districts, and hence to their populations at risk. Main outcome measures were comparison of observed/expected ratios (based on national rates) within bands delineated by concentric circles around point sources of environmental pollution located anywhere in Britain. MAIN RESULTS--The system is illustrated by a study of mortality from mesothelioma and asbestosis near the Plymouth naval dockyards during 1981-87. Within a 3 km radius of the docks the mortality rate for mesothelioma was higher than the national rate by a factor of 8.4, and that for asbestosis was higher by a factor of 13.6. CONCLUSIONS--SAHSU is a new national facility which is rapidly able to provide rates of mortality and cancer incidence for arbitrary circles drawn around any point in Britain. The example around Plymouth of mesothelioma and asbestosis demonstrates the ability of the system to detect an unusual excess of disease in a small locality, although in this case the findings are likely to be related to occupational rather than environmental exposure. PMID:1431704

The mass flow and proposed management of bisphenol A in selected Norwegian waste streams.

PubMed

Arp, Hans Peter H; Morin, Nicolas A O; Hale, Sarah E; Okkenhaug, Gudny; Breivik, Knut; Sparrevik, Magnus

2017-02-01

Current initiatives for waste-handling in a circular economy favor prevention and recycling over incineration or landfilling. However, the impact of such a transition on environmental emissions of contaminants like bisphenol A (BPA) during waste-handling is not fully understood. To address this, a material flow analysis (MFA) was constructed for selected waste categories in Norway, for which the amount recycled is expected to increase in the future; glass, vehicle, electronic, plastic and combustible waste. Combined, 92tons/y of BPA are disposed of via these waste categories in Norway, with 98.5% associated with plastic and electronic waste. During the model year 2011, the MFA showed that BPA in these waste categories was destroyed through incineration (60%), exported for recycling into new products (35%), stored in landfills (4%) or released into the environment (1%). Landfilling led to the greatest environmental emissions (up to 13% of landfilled BPA), and incinerating the smallest (0.001% of incinerated BPA). From modelling different waste management scenarios, the most effective way to reduce BPA emissions are to incinerate BPA-containing waste and avoid landfilling it. A comparison of environmental and human BPA concentrations with CoZMoMAN exposure model estimations suggested that waste emissions are an insignificant regional source. Nevertheless, from monitoring studies, landfill emissions can be a substantial local source of BPA. Regarding the transition to a circular economy, it is clear that disposing of less BPA-containing waste and less landfilling would lead to lower environmental emissions, but several uncertainties remain regarding emissions of BPA during recycling, particularly for paper and plastics. Future research should focus on the fate of BPA, as well as BPA alternatives, in emerging reuse and recycling processes, as part of the transition to a circular economy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Environmental Site Characterization for the Wide Area Mine Sensor Demonstration, Aberdeen Proving Ground, October 1988

DTIC Science & Technology

1991-05-01

AD-A237 045 MP I ENVIRONMENTAL SITE CHARACTERIZATION of EFOR THE WIDE AREA MINE SENSOR DEMONSTRATION, ABERDEEN PROVING GROUND , OCTOBER 1988 T- by...Wide Area Mine Sensor Demonstration, Aberdeen Proving Ground , October 1988 6. AUTHOR(S) Bruce M. Sabol, Thomas E. Berry, Ben L. Garnes 7. PERFORMING... Proving Ground (APG), Maryland. This report presents data that characterize terrain and environmental factors expected to affect WAN sensor performance

Environmental barriers and enablers to physical activity participation among rural adults: a qualitative study.

PubMed

Cleland, Verity; Hughes, Clarissa; Thornton, Lukar; Squibb, Kathryn; Venn, Alison; Ball, Kylie

2015-08-01

Social-ecological models of health behaviour acknowledge environmental influences, but research examining how the environment shapes physical activity in rural settings is limited. This study aimed to explore the environmental factors that act as barriers or facilitators to physical activity participation among rural adults. Forty-nine adults from three regions of rural Tasmania, Australia, participated in semi-structured interviews that explored features of the environment that supported or hindered physical activity. Interviews were digitally recorded, transcribed verbatim and analysed thematically. Four key themes emerged: functionality, diversity, spaces and places for all and realistic expectations. 'Functionality' included connectivity with other destinations, distance, safety, continuity, supporting infrastructure and surfacing. While there was limited 'diversity' of structured activities and recreational facilities, the importance of easy and convenient access to a natural environment that accommodated physical activity was highlighted. 'Spaces and places for all' highlighted the importance of shared-use areas, particularly those that were family- and dog-friendly. Despite desires for more physical activity opportunities, many participants had 'realistic expectations' of what was feasible in rural settings. Functionality, diversity, spaces and places for all and realistic expectations were identified as considerations important for physical activity among rural adults. Further research using quantitative approaches in larger samples is needed to confirm these findings. SO WHAT? Urban-centric views of environmental influences on physical activity are unlikely to be entirely appropriate for rural areas. Evidence-based recommendations are provided for creating new or modifying existing infrastructure to support active living in rural settings.

Durability of Poly(Methyl Methacrylate) Lenses Used in Concentrating Photovoltaic Technology (Revised) (Presentation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, D. C.; Carloni, J. D.; Pankow, J. W.

2012-01-01

Concentrating photovoltaic (CPV) technology recently gained interest based on its expected low levelized cost of electricity, high efficiency, and scalability. Many CPV systems employ Fresnel lenses composed of poly(methyl methacrylate) (PMMA) to obtain a high optical flux density on the cell. The optical and mechanical durability of these lenses, however, is not well established relative to the desired surface life of 30 years. Our research aims to quantify the expected lifetime of PMMA in key market locations (FL, AZ, and CO).

The presence and leachability of antimony in different wastes and waste handling facilities in Norway.

PubMed

Okkenhaug, G; Almås, Å R; Morin, N; Hale, S E; Arp, H P H

2015-11-01

The environmental behaviour of antimony (Sb) is gathering attention due to its increasingly extensive use in various products, particularly in plastics. Because of this it may be expected that plastic waste is an emission source for Sb in the environment. This study presents a comprehensive field investigation of Sb concentrations in diverse types of waste from waste handling facilities in Norway. The wastes included waste electrical and electronic equipment (WEEE), glass, vehicle fluff, combustibles, bottom ash, fly ash and digested sludge. The highest solid Sb concentrations were found in WEEE and vehicle plastic (from 1238 to 1715 mg kg(-1)) and vehicle fluff (from 34 to 4565 mg kg(-1)). The type of acid used to digest the diverse solid waste materials was also tested. It was found that HNO3:HCl extraction gave substantially lower, non-quantitative yields compared to HNO3:HF. The highest water-leachable concentration for wastes when mixed with water at a 1 : 10 ratio were observed for plastic (from 0.6 to 2.0 mg kg(-1)) and bottom ash (from 0.4 to 0.8 mg kg(-1)). For all of the considered waste fractions, Sb(v) was the dominant species in the leachates, even though Sb(iii) as Sb2O3 is mainly used in plastics and other products, indicating rapid oxidation in water. This study also presents for the first time a comparison of Sb concentrations in leachate at waste handling facilities using both active grab samples and DGT passive samples. Grab samples target the total suspended Sb, whereas DGT targets the sum of free- and other chemically labile species. The grab sample concentrations (from 0.5 to 50 μg L(-1)) were lower than the predicted no-effect concentration (PNEC) of 113 μg L(-1). The DGT concentrations were substantially lower (from 0.05 to 9.93 μg L(-1)) than the grab samples, indicating much of the Sb is present in a non-available colloidal form. In addition, air samples were taken from the chimney and areas within combustible waste incinerators, as well as from the vent of WEEE sorting facility. The WEEE vent had the highest Sb concentration (from <100 to 2200 ng m(-3)), which were orders of magnitude higher than the air surrounding the combustible shredder (from 25 to 217 ng m(-3)), and the incinerator chimney (from <30 to 100 ng m(-3)). From these results, it seems evident that Sb from waste is not an environmental concern in Norway, and that Sb is mostly readily recovered from plastic and bottom ash.

The Response of Environmental Capacity for Malaria Transmission in West Africa to Climate Change

NASA Astrophysics Data System (ADS)

Yamana, T. K.; Eltahir, E. A.

2011-12-01

The climate of West Africa is characterized by north-south gradients in temperature and rainfall. Environmental capacity for malaria transmission (e.g. as measured by vectorial capacity) is strongly tied to these two variables; temperature affects the development rate of the malaria parasite, as well as the lifespan of the mosquitoes that transmit the disease, and rainfall is tied to mosquito abundance, as the vector lays its eggs in rain-fed water pools. A change in climate is therefore expected to lead to changes in the distribution of malaria transmission. Current general circulation models agree that the temperature in West Africa is expected to increase by several degrees in the next century. However they predict a wide range of possible rainfall scenarios in the future, from intense drying to significant increases in rainfall (Christensen et al., 2007). The effects these changes will have on environmental capacity for malaria transmission depend on the magnitude and direction of the changes, and on current conditions. For example, malaria transmission will be more sensitive to positive changes in rainfall in dry areas where mosquito populations are currently limited by water availability than in relatively wet areas. Here, we analyze combinations of changes in rainfall and temperature within the ranges predicted by GCMs, and assess the impact these combinations will have on the environmental capacity for malaria transmission. In particular, we identify climate change scenarios that are likely to have the greatest impact on environmental capacity for malaria transmission, as well as geographic "hot spots" where the greatest changes are to be expected. Christensen, J. H., Busuioc, A., & et al. (2007). Regional climate projections. In S. Solomon (Ed.), Climate change 2007: The physical science basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change.

Counting at low concentrations: the statistical challenges of verifying ballast water discharge standards

EPA Science Inventory

Discharge from the ballast tanks of ships is one of the primary vectors of nonindigenous species in marine environments. To mitigate this environmental and economic threat, the U.S. Coast Guard and the U.S. Environmental Protection Agency will regulate the concentration of livin...

40 CFR Table 1 to Subpart A of... - Maximum Concentration of Constituents for Groundwater Protection

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Maximum Concentration of Constituents for Groundwater Protection 1 Table 1 to Subpart A of Part 192 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION PROGRAMS HEALTH AND ENVIRONMENTAL PROTECTION STANDARDS FOR...