PERFLUORINATED COMPOUNDS IN THE CAPE FEAR DRAINAGE BASIN IN NORTH CAROLINA

EPA Science Inventory

Concern over perfluorinated organic compounds (PFCs), e.g., perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), is due to a number of recent studies which show that the PFCs are persistent, bioaccumulative, and toxic. Despite sustained interest in this topic, lit...

Mind the Gap: Persistent and Mobile Organic Compounds-Water Contaminants That Slip Through.

PubMed

Reemtsma, Thorsten; Berger, Urs; Arp, Hans Peter H; Gallard, Hervé; Knepper, Thomas P; Neumann, Michael; Quintana, José Benito; Voogt, Pim de

2016-10-04

The discharge of persistent and mobile organic chemicals (PMOCs) into the aquatic environment is a threat to the quality of our water resources. PMOCs are highly polar (mobile in water) and can pass through wastewater treatment plants, subsurface environments and potentially also drinking water treatment processes. While a few such compounds are known, we infer that their number is actually much larger. This Feature highlights the issue of PMOCs from an environmental perspective and assesses the gaps that appear to exist in terms of analysis, monitoring, water treatment and regulation. On this basis we elaborate strategies on how to narrow these gaps with the intention to better protect our water resources.

The design of an environmentally relevant mixture of persistent organic pollutants for use in in vivo and in vitro studies.

PubMed

Berntsen, Hanne Friis; Berg, Vidar; Thomsen, Cathrine; Ropstad, Erik; Zimmer, Karin Elisabeth

2017-01-01

Amongst the substances listed as persistent organic pollutants (POP) under the Stockholm Convention on Persistent Organic Pollutants (SCPOP) are chlorinated, brominated, and fluorinated compounds. Most experimental studies investigating effects of POP employ single compounds. Studies focusing on effects of POP mixtures are limited, and often conducted using extracts from collected specimens. Confounding effects of unmeasured substances in such extracts may bias the estimates of presumed causal relationships being examined. The aim of this investigation was to design a model of an environmentally relevant mixture of POP for use in experimental studies, containing 29 different chlorinated, brominated, and perfluorinated compounds. POP listed under the SCPOP and reported to occur at the highest levels in Scandinavian food, blood, or breast milk prior to 2012 were selected, and two different mixtures representing varying exposure scenarios constructed. The in vivo mixture contained POP concentrations based upon human estimated daily intakes (EDIs), whereas the in vitro mixture was based upon levels in human blood. In addition to total in vitro mixture, 6 submixtures containing the same concentration of chlorinated + brominated, chlorinated + perfluorinated, brominated + perfluorinated, or chlorinated, brominated or perfluorinated compounds only were constructed. Using submixtures enables investigating the effect of adding or removing one or more chemical groups. Concentrations of compounds included in feed and in vitro mixtures were verified by chemical analysis. It is suggested that this method may be utilized to construct realistic mixtures of environmental contaminants for toxicity studies based upon the relative levels of POP to which individuals are exposed.

Nontargeted Biomonitoring of Halogenated Organic Compounds in Two Ecotypes of Bottlenose Dolphins (Tursiops truncatus) from the Southern California Bight

PubMed Central

2015-01-01

Targeted environmental monitoring reveals contamination by known chemicals, but may exclude potentially pervasive but unknown compounds. Marine mammals are sentinels of persistent and bioaccumulative contaminants due to their longevity and high trophic position. Using nontargeted analysis, we constructed a mass spectral library of 327 persistent and bioaccumulative compounds identified in blubber from two ecotypes of common bottlenose dolphins (Tursiops truncatus) sampled in the Southern California Bight. This library of halogenated organic compounds (HOCs) consisted of 180 anthropogenic contaminants, 41 natural products, 4 with mixed sources, 8 with unknown sources, and 94 with partial structural characterization and unknown sources. The abundance of compounds whose structures could not be fully elucidated highlights the prevalence of undiscovered HOCs accumulating in marine food webs. Eighty-six percent of the identified compounds are not currently monitored, including 133 known anthropogenic chemicals. Compounds related to dichlorodiphenyltrichloroethane (DDT) were the most abundant. Natural products were, in some cases, detected at abundances similar to anthropogenic compounds. The profile of naturally occurring HOCs differed between ecotypes, suggesting more abundant offshore sources of these compounds. This nontargeted analytical framework provided a comprehensive list of HOCs that may be characteristic of the region, and its application within monitoring surveys may suggest new chemicals for evaluation. PMID:25526519

The contentious nature of soil organic matter.

PubMed

Lehmann, Johannes; Kleber, Markus

2015-12-03

The exchange of nutrients, energy and carbon between soil organic matter, the soil environment, aquatic systems and the atmosphere is important for agricultural productivity, water quality and climate. Long-standing theory suggests that soil organic matter is composed of inherently stable and chemically unique compounds. Here we argue that the available evidence does not support the formation of large-molecular-size and persistent 'humic substances' in soils. Instead, soil organic matter is a continuum of progressively decomposing organic compounds. We discuss implications of this view of the nature of soil organic matter for aquatic health, soil carbon-climate interactions and land management.

OVERVIEW OF UIN/CEC LRTAP PROTOCOLS ON POPS AND HEAVY METALS

EPA Science Inventory

The purpose of this workshop was to review the current state-of-the-science for persistent organic pollutants and heavy metal compounds, especially additional developments since the conclusion of the negotiations of the Protocols on these compounds under the Convention on Long Ra...

Working group on future trends

USGS Publications Warehouse

,; O'Shea, Thomas J.; Reeves, Randall R.; Long, Alison Kirk

1999-01-01

This working group did not divide into subgroups, and its report consists of a unified document in a format somewhat different than those of the other working groups. The group considered four major topics: (1) projected "new" contaminants of future concern; (2) future trends with contaminants currently known to be issues for marine mammals; (3) future needs to improve and insure consistency of sample collection and analyses; and (4) future management needs.The problems of persistent organic pollutants will remain well into the foreseeable future. A general decline in levels of persistent organic pollutants in the marine environment is not anticipated. there is every likelihood that the environmental trends of halogenated organic compounds, such as polybromated diphenyl ethers and chlorinated paraffins, will parallel production trends, as demonstrated with well known chemical contaminants such as PCBs (polychlorinated biphenyls) and DDT (dichlorodiphenyltrichloroethane). While the environmental levels of some compounds may be slowly declining, many are still within the ranges where subtle toxic effects are to be anticipated. Trends in contaminants must be placed in a regional context, and rates and directions of change are often region-specific. For example, in the Southern Hemisphere the concentrations of PCBs appear to be increasing. The rates of change of many contaminants in the Southern hemisphere are poorly known, and this region may be at future risk.Much of the research on contaminants and marine mammals has focused on the problem of persistent organochloride chemicals such as PCBs and DDT, which are a continuing and global problem. Potential problems caused by other persistent, toxic, and bioaccumulative substances (PTBSs) cannot currently be addressed due to the lack of basic information on their production, use, exposure, and effects (Environmental Protection Agency 1998). It is currently estimated that there are roughly 2400 lipophilic and persistent chemicals, of which 390 are PTBSs. In order to prevent long-term pollution from these largely unknown chemicals, chemical industries should disclose basic information on such compounds, and this information should be made widely available. This will require enhanced international cooperation, preferably within the existing framework of chemical contaminant programs, such as the Existing Chemicals Program of the Organization for Economic Cooperation and Development (1991) and the Program on persistent Organic Pollutants of the United National Environmental Programme (1998).Monitoring studies are essential to the description and understanding of pollutants. It is necessary to exploit existing analytical techniques to identify as many anthropogenic compounds as possible in marine mammal tissues in order to expand the identification of existing and new chemicals that accumulate in, and pose threats to, these species.

BIOPLUME MODEL FOR CONTAMINANT TRANSPORT AFFECTED BY OXYGEN LIMITED BIODEGRADATION

EPA Science Inventory

Many of the organic pollutants entering ground water are potentially biodegradable in the subsurface. This potential has been demonstrated in aquifers contaminated by wood-creosoting process wastes. The persistence of many of these organic compounds in the subsurface indicated ...

Volatile Halogenated Organic Compounds Released to Seawater from Temperate Marine Macroalgae

NASA Astrophysics Data System (ADS)

Gschwend, Philip M.; Macfarlane, John K.; Newman, Kathleen A.

1985-03-01

Volatile halogenated organic compounds synthesized by various industrial processes are troublesome pollutants because they are persistent in terrestrial ecosystems and because they may be present in sufficient quantities to alter the natural atmospheric cycles of the halogens. Certain of these compounds, including polybromomethanes and several previously unobserved alkyl monohalides and dihalides, appear to be natural products of the marine environment. A variety of temperate marine macroalgae (the brown algae Ascophyllum nodosum and Fucus vesiculosis, the green algae Enteromorpha linza and Ulva lacta, and the red alga Gigartina stellata) not only contain volatile halogenated organic compounds but also release them to seawater at rates of nanograms to micrograms of each compound per gram of dry algae per day. The macroalgae may be an important source of bromine-containing material released to the atmosphere.

Inorganic PM in poultry house using rice hull bedding

USDA-ARS?s Scientific Manuscript database

The persistence and long life expectancy of ammonia, odors and toxic pollutants from poultry houses may be due to the ability of suspended particulate matters (SPM) to serve as carriers for odorous compounds such as ammonium ions and volatile organic compounds. SPM is generated from the feed, anima...

HUMAN BLOOD AND ENVIRONMENTAL MEDIA SCREENING METHOD FOR PESTICIDES AND POLYCHLORINATED BIPHENYL COMPOUNDS USING LIQUID EXTRACTION AND GAS CHROMATOGRAPHY-MASS SPECTROMETRY ANALYSIS

EPA Science Inventory

Screening assessment methods have been developed for semi- and non-volatile persistent organic pollutants (POPs) for human blood and solid environmental media. The specific methodology is developed for measuring the presence of "native" compounds, specifically, a var...

Molecular and microscopic insights into the persistence of soil organic matter in a red pine rhizosphere

USDA-ARS?s Scientific Manuscript database

Microbially-derived carbon inputs to soils play an important role in stabilization of soil organic matter (SOM), but detailed knowledge of basic mechanisms of carbon (C) cycling, such as stabilization of organic C compounds originating from rhizodeposition, is lacking. This study aimed to investigat...

Transport and fate of organic wastes in groundwater at the Stringfellow hazardous waste disposal site, southern California

USGS Publications Warehouse

Leenheer, J.A.; Hsu, J.; Barber, L.B.

2001-01-01

In January 1999, wastewater influent and effluent from the pretreatment plant at the Stringfellow hazardous waste disposal site were sampled along with groundwater at six locations along the groundwater contaminant plume. The objectives of this sampling and study were to identify at the compound class level the unidentified 40-60% of wastewater organic contaminants, and to determine what organic compound classes were being removed by the wastewater pretreatment plant, and what organic compound classes persisted during subsurface waste migration. The unidentified organic wastes are primarily chlorinated aromatic sulfonic acids derived from wastes from DDT manufacture. Trace amounts of EDTA and NTA organic complexing agents were discovered along with carboxylate metabolites of the common alkylphenolpolyethoxylate plasticizers and nonionic surfactants. The wastewater pretreatment plant removed most of the aromatic chlorinated sulfonic acids that have hydrophobic neutral properties, but the p-chlorobenzenesulfonic acid which is the primary waste constituent passed through the pretreatment plant and was discharged in the treated wastewaters transported to an industrial sewer. During migration in groundwater, p-chlorobenzenesulfonic acid is removed by natural remediation processes. Wastewater organic contaminants have decreased 3- to 45-fold in the groundwater from 1985 to 1999 as a result of site remediation and natural remediation processes. The chlorinated aromatic sulfonic acids with hydrophobic neutral properties persist and have migrated into groundwater that underlies the adjacent residential community. Copyright ?? 2001 .

Effects of halogenated aromatics/aliphatics and nitrogen(N)-heterocyclic aromatics on estimating the persistence of future pharmaceutical compounds using a modified QSAR model.

PubMed

Lim, Seung Joo; Fox, Peter

2014-02-01

The effects of halogenated aromatics/aliphatics and nitrogen(N)-heterocyclic aromatics on estimating the persistence of future pharmaceutical compounds were investigated using a modified half life equation. The potential future pharmaceutical compounds investigated were approximately 2000 pharmaceutical drugs currently undergoing the United States Food and Drug Administration (US FDA) testing. EPI Suite (BIOWIN) model estimates the fates of compounds based on the biodegradability under aerobic conditions. While BIOWIN considered the biodegradability of a compound only, the half life equation used in this study was modified by biodegradability, sorption and cometabolic oxidation. It was possible that the potential future pharmaceutical compounds were more accurately estimated using the modified half life equation. The modified half life equation considered sorption and cometabolic oxidation of halogenated aromatic/aliphatics and nitrogen(N)-heterocyclic aromatics in the sub-surface, while EPI Suite (BIOWIN) did not. Halogenated aliphatics in chemicals were more persistent than halogenated aromatics in the sub-surface. In addition, in the sub-surface environment, the fates of organic chemicals were much more affected by halogenation in chemicals than by nitrogen(N)-heterocyclic aromatics. © 2013.

The Composition of Organic Aerosols in Southeast Asia During The 2006 Haze Episode

NASA Astrophysics Data System (ADS)

Jun, H.; Zielinska, B.; Balasubramanian, R.

2007-12-01

The regional smoke haze in Southeast Asia is a recurring air pollution problem. Uncontrolled forest fires from land-clearing activities in Sumatra and Borneo, and to a lesser extent Malaysia, have occurred almost every dry season since the late 1990s. The smoke haze that took place in October 2006 shrouded an estimated 215,000 square miles of land on Indonesia's islands of Sumatra and Borneo, and persisted for several weeks. Satellite pictures showed numerous hotspots in both Sumatra and Kalimantan. The prevailing, South-Southwesterly, winds blew smoke from land and forest fires in central and south Sumatra to Singapore, affecting the regional air quality significantly and reducing atmospheric visibility. During this haze episode, we carried out an intensive field study in Singapore to characterize the composition of organic aerosols, which usually account for a large fraction of airborne particulate matter (PM). A total of 17 PM samples were collected while the hazy atmospheric conditions persisted in Singapore, and subjected to accelerated solvent extraction with dichloromethane and acetone. The extracted compounds were grouped into three major fractions (n-alkanes, polycyclic aromatic hydrocarbons, and polar organic compounds). More than 180 particulate-bound organic compounds were determined using gas chromatography/mass spectrometry (GC-MS). In order to investigate the origin of organic species, the carbon preference indexes as well as diagnostic ratios were used. The compositional differences of organic aerosols between the haze- and non- haze periods will be presented. The atmospheric implications of the composition of organic aerosols of biomass burning origin will be discussed. Keywords: smoke haze, organic aerosols, n-alkanes, polycyclic aromatic hydrocarbons, polar organic compounds

Behaviour and fate of nine recycled water trace organics during managed aquifer recharge in an aerobic aquifer

NASA Astrophysics Data System (ADS)

Patterson, B. M.; Shackleton, M.; Furness, A. J.; Bekele, E.; Pearce, J.; Linge, K. L.; Busetti, F.; Spadek, T.; Toze, S.

2011-03-01

The fate of nine trace organic compounds was evaluated during a 12 month large-scale laboratory column experiment. The columns were packed with aquifer sediment and evaluated under natural aerobic and artificial anaerobic geochemical conditions, to assess the potential for natural attenuation of these compounds during aquifer passage associated with managed aquifer recharge (MAR). The nine trace organic compounds were bisphenol A (BPA), 17β-estradiol (E2), 17α-ethynylestradiol (EE2), N-nitrosodimethylamine (NDMA), N-nitrosomorpholine (NMOR), carbamazepine, oxazepam, iohexol and iodipamide. In the low organic carbon content Spearwood sediment, all trace organics were non-retarded with retardation coefficients between 1.0 and 1.2, indicating that these compounds would travel at near groundwater velocities within the aquifer. The natural aerobic geochemical conditions provided a suitable environment for the rapid degradation for BPA, E2, iohexol (half life < 1 day). Lag-times for the start of degradation of these compounds ranged from < 15 to 30 days. While iodipamide was persistent under aerobic conditions, artificial reductive geochemical conditions promoted via the addition of ethanol, resulted in rapid degradation (half life < 1 days). Pharmaceuticals (carbamazepine and oxazepam) and disinfection by-products (NDMA and NMOR) did not degrade under either aerobic or anaerobic aquifer geochemical conditions (half life > 50 days). Field-based validation experiments with carbamazepine and oxazepam also showed no degradation. If persistent trace organics are present in recycled waters at concentrations in excess of their intended use, natural attenuation during aquifer passage alone may not result in extracted water meeting regulatory requirements. Additional pre treatment of the recycled water would therefore be required.

Organic Nanocrystals with Bright Red Persistent Room-Temperature Phosphorescence for Biological Applications.

PubMed

Fateminia, S M Ali; Mao, Zhu; Xu, Shidang; Yang, Zhiyong; Chi, Zhenguo; Liu, Bin

2017-09-25

Persistent room-temperature phosphorescence (RTP) in pure organic materials has attracted great attention because of their unique optical properties. The design of organic materials with bright red persistent RTP remains challenging. Herein, we report a new design strategy for realizing high brightness and long lifetime of red-emissive RTP molecules, which is based on introducing an alkoxy spacer between the hybrid units in the molecule. The spacer offers easy Br-H bond formation during crystallization, which also facilitates intermolecular electron coupling to favor persistent RTP. As the majority of RTP compounds have to be confined in a rigid environment to quench nonradiative relaxation pathways for bright phosphorescence emission, nanocrystallization is used to not only rigidify the molecules but also offer the desirable size and water-dispersity for biomedical applications. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of Feeding Schedule on Fractionated Particulate Matter Distribution in Rooster House

USDA-ARS?s Scientific Manuscript database

The persistence and long life expectancy of ammonia, odors and toxic pollutants from poultry houses may be due to the ability of suspended particulate matters (SPM) to serve as carriers for odorous compounds such as ammonium ions and volatile organic compounds. SPM is generated from the feed, anima...

Trends and the effect of management on macronutrients in fractionated particulate matter in rooster house

USDA-ARS?s Scientific Manuscript database

The persistence and long life expectancy of ammonia, odors and toxic pollutants from poultry houses may be due to the ability of suspended particulate matters (SPM) to serve as carriers for odorous compounds such as ammonium ions and volatile organic compounds. SPM is generated from the feed, anima...

Persistence and potential effects of complex organic contaminant mixtures in wastewater-impacted streams

USGS Publications Warehouse

Barber, Larry B.; Keefe, Steffanie H.; Brown, Greg K.; Furlong, Edward T.; Gray, James L.; Kolpin, Dana W.; Meyer, Michael T.; Sandstrom, Mark W.; Zaugg, Steven D.

2013-01-01

Natural and synthetic organic contaminants in municipal wastewater treatment plant (WWTP) effluents can cause ecosystem impacts, raising concerns about their persistence in receiving streams. In this study, Lagrangian sampling, in which the same approximate parcel of water is tracked as it moves downstream, was conducted at Boulder Creek, Colorado and Fourmile Creek, Iowa to determine in-stream transport and attenuation of organic contaminants discharged from two secondary WWTPs. Similar stream reaches were evaluated, and samples were collected at multiple sites during summer and spring hydrologic conditions. Travel times to the most downstream (7.4 km) site in Boulder Creek were 6.2 h during the summer and 9.3 h during the spring, and to the Fourmile Creek 8.4 km downstream site times were 18 and 8.8 h, respectively. Discharge was measured at each site, and integrated composite samples were collected and analyzed for >200 organic contaminants including metal complexing agents, nonionic surfactant degradates, personal care products, pharmaceuticals, steroidal hormones, and pesticides. The highest concentration (>100 μg L–1) compounds detected in both WWTP effluents were ethylenediaminetetraacetic acid and 4-nonylphenolethoxycarboxylate oligomers, both of which persisted for at least 7 km downstream from the WWTPs. Concentrations of pharmaceuticals were lower (<1 μg L–1), and several compounds, including carbamazepine and sulfamethoxazole, were detected throughout the study reaches. After accounting for in-stream dilution, a complex mixture of contaminants showed little attenuation and was persistent in the receiving streams at concentrations with potential ecosystem implications.

Meta-Analysis of Mass Balances Examining Chemical Fate during Wastewater Treatment

PubMed Central

2008-01-01

Mass balances are an instructive means for investigating the fate of chemicals during wastewater treatment. In addition to the aqueous-phase removal efficiency (Φ), they can inform on chemical partitioning, transformation, and persistence, as well as on the chemical loading to streams and soils receiving, respectively, treated effluent and digested sewage sludge (biosolids). Release rates computed on a per-capita basis can serve to extrapolate findings to a larger scale. This review examines over a dozen mass balances conducted for various organic wastewater contaminants, including prescription drugs, estrogens, fragrances, antimicrobials, and surfactants of differing sorption potential (hydrophobicity), here expressed as the 1-octanol−water partition coefficient (KOW) and the organic carbon normalized sorption coefficient (KOC). Major challenges to mass balances are the collection of representative samples and accurate quantification of chemicals in sludge. A meta-analysis of peer-reviewed data identified sorption potential as the principal determinant governing chemical persistence in biosolids. Occurrence data for organic wastewater compounds detected in digested sludge followed a simple nonlinear model that required only KOW or KOC as the input and yielded a correlation coefficient of 0.9 in both instances. The model predicted persistence in biosolids for the majority (>50%) of the input load of organic wastewater compounds featuring a log10KOW value of greater than 5.2 (log10KOC > 4.4). In contrast, hydrophobicity had no or only limited value for estimating, respectively, Φ and the overall persistence of a chemical during conventional wastewater treatment. PMID:18800497

Persistent organic pollutants (POPs) in the atmosphere of coastal areas of the Ross Sea, Antarctica: Indications for long-term downward trends.

PubMed

Pozo, Karla; Martellini, Tania; Corsolini, Simonetta; Harner, Tom; Estellano, Victor; Kukučka, Petr; Mulder, Marie D; Lammel, Gerhard; Cincinelli, Alessandra

2017-07-01

Passive air samplers were used to evaluate long-term trends and spatial distribution of trace organic compounds in Antarctica. Duplicate PUF disk samplers were deployed at six automatic weather stations in the coastal area of the Ross sea (East Antarctica), between December 2010 and January 2011, during the XXVI Italian Scientific Research Expedition. Among the investigated persistent organic compounds, Hexachlorobenzene was the most abundant, with air concentrations ranging from 0.8 to 50 pg m -3 . In general, the following decreasing concentration order was found for the air samples analyzed: HCB > PeCB > PCBs > DDTs > HCHs. While HCB concentrations were in the same range as those reported in the atmosphere of other Antarctic sampling areas and did not show a decline, HCHs and DDTs levels were lower or similar to those determined one or two decades ago. In general, the very low concentrations reflected the pristine state of the East Antarctica air. Backward trajectories indicated the prevalence of air masses coming from the Antarctic continent. Local contamination and volatilization from ice were suggested as potential sources for the presence of persistent organic pollutants in the atmosphere. Copyright © 2017 Elsevier Ltd. All rights reserved.

Organic compounds in the particulate matter from burning organic soils

Treesearch

Charles K. McMahon; Jerry D. White; Skevos N. Tsoukalas

1985-01-01

This paper is directed to people interested in the environmental impact of natural emissions. Natural emissions are common and contribute significantly to tropospheric background levels. Several million hectares of the United States are covered by organic soils. During droughts, these soils can ignite and support slow combustion which often persists for weeks causing...

Comparison of perfluorooctanoic acid mobility in soil with and without alfalfa

USDA-ARS?s Scientific Manuscript database

Perfluorooctanoic acid (PFOA) is a fully fluorinated organic compound (C8HF15O2) that is widely used in consumer products as a surfactant because of its chemical resistance to stains, grease, and water. Perfluorooctanoic acid is a persistent organic pollutant because it is globally distributed, stab...

Vegetation effects on soil organic matter chemistry of aggregate fractions in a Hawaiian forest

USDA-ARS?s Scientific Manuscript database

We examined chemical changes from live plant tissue to soil organic matter (SOM) to determine the persistence of individual plant compounds into soil aggregate fractions. We characterized the tissue chemistry of a slow- (Dicranopteris linearis) and fast-decomposing species (Cheirodendron trigynum) a...

Selected persistent organic pollutants (POPs) in the Italian environment.

PubMed

Miniero, Roberto; De Felip, Elena; Magliuolo, Mariella; Ferri, Fabiola; Di Domenico, Alessandro

2005-01-01

The ratification of the Stockholm Convention on Persistent Organic Pollutants is a departure point for several considerations on their presence in environmental matrices. In this paper, the Italian situation is presented with emphasis on the most toxic compounds--chemicals with dioxin-like toxic action, and the activity in the area of interest of the Istituto Superiore di Sanità. Biotic, as well as abiotic matrices have been taken in consideration and, where possible, a comparation between their contamination levels with the levels reported on similar matrices by other European countries has been reported.

A combined electrocoagulation-electrooxidation treatment for industrial wastewater.

PubMed

Linares-Hernández, Ivonne; Barrera-Díaz, Carlos; Bilyeu, Bryan; Juárez-GarcíaRojas, Pablo; Campos-Medina, Eduardo

2010-03-15

This study addresses the elimination of persistent organic compounds in industrial wastewater using a synergistic combination of electrocoagulation and electrooxidation. Electrocoagulation is a relatively quick process (30 min), which is very effective in removing colloidal and suspended particles, as seen in changes in coliforms, turbidity, and color and in the general absorbance by UV-vis spectroscopy. However, it is relatively ineffective in eliminating stable persistent organic compounds--in this work, only half of the COD was eliminated from wastewater and an oxidation peak in the cyclic voltammetry scan remained. Electrooxidation is very effective in breaking down organic compounds through oxidation as reflected in the elimination of COD, BOD(5), and oxidative peak in cyclic voltammetry, but requires so much time (21 h) that it has very limited practicality, especially when colloidal and suspended particles are present. Electrooxidative mineralization of electrocoagulated wastewater, in which most of the colloids and charged species have been removed, takes less than 2h. In the coupled technique, electrocoagulation quickly coagulates and removes the colloidal and suspended particles, as well as many charged species, then electrooxidation oxidizes the remaining organics. The coupled process eliminates COD, BOD(5), color, turbidity, and coliforms in a practical amount of time (2h). (c) 2009 Elsevier B.V. All rights reserved.

Photochemical transformation of phenylurea herbicides in surface waters: a model assessment of persistence, and implications for the possible generation of hazardous intermediates.

PubMed

Fabbri, Debora; Minella, Marco; Maurino, Valter; Minero, Claudio; Vione, Davide

2015-01-01

This work models the phototransformation kinetics in surface waters of five phenylurea herbicides (diuron, fenuron, isoproturon, metoxuron and chlortoluron), for which important photochemical parameters are available in the literature (direct photolysis quantum yields and reaction rate constants with ·OH, CO3(-·) and the triplet states of chromophoric dissolved organic matter, (3)CDOM*). Model calculations suggest that isoproturon and metoxuron would be the least photochemically persistent and diuron the most persistent compound. Reactions with ·OH and (3)CDOM* would be the main phototransformation pathways for all compounds in the majority of environmental conditions. Reaction with CO3(-) could be important in waters with low dissolved organic carbon (DOC), while direct photolysis would be negligible for fenuron, quite important for chlortoluron, and somewhat significant for the other compounds. The direct photolysis of metoxuron and diuron is known to increase toxicity, and such a photoreaction pathway would be enhanced at intermediate DOC values (1-4 mg C L(1)). The reaction between phenylureas and ·OH is known to produce toxic intermediates, differently from (3)CDOM*. Therefore, the shift of reactivity from ·OH to (3)CDOM* with increasing DOC could reduce the environmental impact of photochemical transformation. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Characteristics of organic pollutants in the sediments from a typical electronics industrial zone].

PubMed

Liu, Jin; Deng, Dai-Yong; Xu, Mei-Ying; Sun, Guo-Ping

2013-03-01

In order to investigate the contamination status of organic pollutants in a river of a typical electrical equipment industrial area, Ronggui, Foshan, the sediments were sampled for the composition, concentration and occurrence analysis of organic pollutants. The polar and non-polar fractionation methods were employed for the fingerprint establishment of organic pollutants. One hundred and seventy-one of organic chemicals including ten categories of alkanes, alkenes, polycyclic aromatic hydrocarbons, benzene, heterocyclic compounds, phthalate esters, aldehydes, ketones, polar compounds, silicon-containing material as well as alkyl esters were examined. The number of different categories of the detected organic pollutants in a descending order was: alkanes > polar compounds > polycyclic aromatic hydrocarbons > aldehydes and ketones > heterocyclic compounds > benzene homologues, phthalate ester > alkyl esters > silicon material > olefins. The abundance of detected organic pollutants in a descending order was: alkanes > polar compounds > alkyl esters > olefins > polycyclic aromatic hydrocarbons > phthalates > silicon material > aldehydes and ketones > heterocyclic compounds > benzene homologues. Among the 51 kinds of alkanes detected, nonadecane accounted for 14.83%, and the persistent organic pollutants accounted for 2.33% of the total organic matter. Compared to similar studies, there were 51 kinds of alkanes and they accounted for 55.5% of the total organic chemicals, showing high diversity and abundance. In addition, some electronics industry-related organic pollutants such as silicone materials were also detected in high frequency.

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.

The Pollution of the Oceans and Great Lakes by Persistent Organic Pollutants

NASA Astrophysics Data System (ADS)

Lohmann, R.; Muir, D.

2012-12-01

The presence of man-made organic chemicals across the Great Lakes and Oceans is widespread. Especially in the northern hemisphere, legacy persistent organic pollutants (POPs) such as polychlorinated biphenyls or DDT can be detected almost everywhere. Despite their ban several decades ago, concentrations are only declining slowly in the atmosphere, while time trends are not available for the waters of the world. While concentrations are often low (picogram per liter range), their bioaccumulation still causes adverse effects in top predators, including humans. Our results for legacy POPs highlight that oceans and the Great Lakes are by now re-releasing these compounds back to the atmosphere. More recently banned POPs include brominated flame retardants and perfluorinated compounds. Atmospheric concentrations are slowly declining, while their impacts on the aquatic environment will be felt for decades to come. Due to the paucity of aqueous data on POPs, we called for a global effort to monitor key POPs using passive samplers (AQUA-GAPS). Our recent cruise results show perfluorinated compounds to be present in all ocean basins, suggesting that they will remain for good. As of yet unknown are the presence and effects of additional hundreds to thousands industrial chemicals that are suspected of being persistent, bioaccumulative and toxic. Several of these have been identified as compounds of potential concern, but few have been investigated in the oceans. The solution to the pollution of POPs will have to rely on better chemical screening prior to high-volume production. The recent REACH legislation by the EU is a step in the right direction, but will not prevent the on-going release of man-made chemicals over the next few decades, many of which are already in use and will continue to be released over time.

The fate of organic micropollutants during long-term/long-distance river bank filtration.

PubMed

Hamann, Enrico; Stuyfzand, Pieter J; Greskowiak, Janek; Timmer, Harrie; Massmann, Gudrun

2016-03-01

The fate of organic micropollutants during long-term/long-distance river bank filtration (RBF) at a temporal scale of several years was investigated along a row of monitoring wells perpendicular to the Lek River (the Netherlands). Out of 247 compounds, which were irregularly analyzed in the period 1999-2013, only 15 were detected in both the river and river bank observation wells. Out of these, 10 compounds (1,4-dioxan, 1,5-naphthalene disulfonate (1,5-NDS), 2-amino-1,5-NDS, 3-amino-1,5-NDS, AOX, carbamazepine, EDTA, MTBE, toluene and triphenylphosphine oxide) showed fully persistent behavior (showing no concentration decrease at all), even after 3.6 years transit time. The remaining 5 compounds (1,3,5-naphthalene trisulfonate (1,3,5-NTS), 1,3,6-NTS, diglyme, iopamidol, triglyme) were partially removed. Their reactive transport parameters (removal rate constants/half-lives, retardation coefficients) were inferred from numerical modeling. In addition, maximum half-lives for 14 of the fully removed compounds, for which the data availability was sufficient to deduce 100% removal during sub-surface passage, were approximated based on travel times to the nearest well. The study is one of very few reporting on the long-term field-scale behavior of organic micropollutants. It highlights the efficiency of RBF for water quality improvement as a pre-treatment step for drinking water production. However, it also shows the very persistent behavior of various compounds in groundwater. Copyright © 2015 Elsevier B.V. All rights reserved.

Tissue concentrations of organic contaminants in fish and their biological effects in a wastewater-dominated urban stream

USDA-ARS?s Scientific Manuscript database

Data are presented on the fish tissue concentrations of persistent organic compounds and alkylphenol and alkylphenol ethoxylates (APEs) in large-mouth bass collected from a waste water dominated stream in downtown Chicago. The fish residue concentrations of APEs are compared to concentrations of th...

INHIBITION OF VASOPRESSIN RELEASE IN THE RAT SUPRAOPTIC NUCLEUS BY EXPOSRUE TO THE PBDE MIXTURE (DE-71) IN VITRO.

EPA Science Inventory

Introduction

Persistent organic pollutants (POPs) are long-lived toxic organic compounds and are of major concern for human

and ecosystem health1,2 . Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are

examples of such chemicals...

In-Situ Chemical Oxidation

DTIC Science & Technology

2006-08-01

Persulfate S2O82- + 2 e- 2 SO42- 2.1 V (persulfate) (9) ·SO4- + e- SO42- 2.6 V ( sulfate radical) (10) 1 Persistence...E = susceptible Notes: 1 Persulfate/ sulfate radical reactivity studies with 66 organic compounds and isomers under various conditions have been...may produce reac- tion byproducts that include dichloroacetaldehyde and dichloroacetic acid , compounds with lower toxicity. Similarly, oxidation of

Soil organic matter persistence as a stochastic process: age and transit time distributions of carbon in soils

NASA Astrophysics Data System (ADS)

Sierra, Carlos

2017-04-01

The question of why some organic matter is more persistent than other that decomposes quickly in soils has sparkled a large amount of research in recent years. Persistence is commonly characterized as the turnover or mean residence time of specific compounds or soil organic matter (SOM) pools. However, turnover and residence times are ambiguous measures of persistence, which is better characterized by the probability distribution of ages in the system and in particular pools. We calculated age distributions for a wide range of SOM models, which showed long-tail distributions far from the mean value. Age and transit time distributions from a variety of models also showed: 1) transit times are lower than ages of SOM, 2) turnover times differ significantly from mean ages in slow cycling pools, 3) change in the inputs, without changes in the allocation of photosynthetic products, has no effect on transit times, but does affect system and pool ages. We propose an index to assess persistence of C in soils that can be derived from observations alone or from models. We also ask whether random chance is an important contributor to the persistence of SOM.

[The vanadium compounds: chemistry, synthesis, insulinomimetic properties].

PubMed

Fedorova, E V; Buriakina, A V; Vorob'eva, N M; Baranova, N I

2014-01-01

The review considers the biological role of vanadium, its participation in various processes in humans and other mammals, and the anti-diabetic effect of its compounds. Vanadium salts have persistent hypoglycemic and antihyperlipidemic effects and reduce the probability of secondary complications in animals with experimental diabetes. The review contains a detailed description of all major synthesized vanadium complexes having antidiabetic activity. Currently, vanadium complexes with organic ligands are more effective and safer than the inorganic salts. Despite the proven efficacy of these compounds as the anti-diabetic agents in animal models, only one organic complex of vanadium is currently under the second phase of clinical trials. All of the considered data suggest that vanadium compound are a new promising class of drugs in modern pharmacotherapy of diabetes.

Estimating the fates of organic contaminants in an aquifer using QSAR.

PubMed

Lim, Seung Joo; Fox, Peter

2013-01-01

The quantitative structure activity relationship (QSAR) model, BIOWIN, was modified to more accurately estimate the fates of organic contaminants in an aquifer. The predictions from BIOWIN were modified to include oxidation and sorption effects. The predictive model therefore included the effects of sorption, biodegradation, and oxidation. A total of 35 organic compounds were used to validate the predictive model. The majority of the ratios of predicted half-life to measured half-life were within a factor of 2 and no ratio values were greater than a factor of 5. In addition, the accuracy of estimating the persistence of organic compounds in the sub-surface was superior when modified by the relative fraction adsorbed to the solid phase, 1/Rf, to that when modified by the remaining fraction of a given compound adsorbed to a solid, 1 - fs.

Revisiting the concept of recalcitrance and organic matter persistence in soils and aquatic systems: Does environment trump chemistry?

NASA Astrophysics Data System (ADS)

Marin-Spiotta, E.

2014-12-01

Most ecological models of decomposition rely on plant litter chemistry. However, growing evidence suggests that the chemical composition of organic matter (OM) is not a good predictor of its eventual fate in terrestrial or aquatic environments. New data on variable decomposition rates of select organic compounds challenge concepts of chemical recalcitrance, i.e. the inherent ability of certain molecular structures to resist biodegradation. The role of environmental or "ecosystem" properties on influencing decomposition dates back to some of the earliest research on soil OM. Despite early recognition that the physical and aqueous matrices are critical in determining the fate of organic compounds, the prevailing paradigm hinges on intrinsic chemical properties as principal predictors of decay rate. Here I build upon recent reviews and discuss new findings that contribute to three major transformations in our understanding of OM persistence: (1) a shift away from an emphasis on chemical recalcitrance as a primary predictor of turnover, (2) new interpretations of radiocarbon ages which challenge predictions of reactivity, and (3) the recognition that most detrital OM accumulating in soils and in water has been microbially processed. Predictions of OM persistence due to aromaticity are challenged by high variability in lignin and black C turnover observed in terrestrial and aquatic environments. Contradictions in the behavior of lignin are, in part, influenced by inconsistent methodologies among research communities. Even black C, long considered to be one of the most recalcitrant components of OM, is susceptible to biodegradation, challenging predictions of the stability of aromatic structures. At the same time, revised interpretations of radiocarbon data suggest that organic compounds can acquire long mean residence times by various mechanisms independent of their molecular structure. Understanding interactions between environmental conditions and biological reactivity can improve predictions of how disturbance events can further stabilize or destabilize organic C pools, with implications for terrestrial C storage, aquatic C cycling, and climate change.

Persistent organic pollutants in human breast milk from Asian countries.

PubMed

Tanabe, Shinsuke; Kunisue, Tatsuya

2007-03-01

In this paper, we concisely reviewed the contamination of persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs), hexachlorobenzene (HCB) in human breast milk collected from Asian countries such as Japan, China, Philippines, Vietnam, Cambodia, India, Malaysia, and Indonesia during 1999-2003. Dioxins, PCBs, CHLs in Japanese, and DDTs in Vietnamese, Chinese, Cambodian, Malaysian, and HCHs in Chinese, Indian, and HCB in Chinese breast milk were predominant. In India, levels of dioxins and related compounds (DRCs) in the mothers living around the open dumping site were notably higher than those from the reference site and other Asian developing countries, indicating that significant pollution sources of DRCs are present in the dumping site of India and the residents there have been exposed to relatively higher levels of these contaminants possibly via bovine milk.

Groundwater dating with the helium-tritium method to assess the long-term persistence of pharmaceuticals and their residues in groundwater

NASA Astrophysics Data System (ADS)

Massmann, G.; Burke, V.; Hass, U.; Dünnbier, U.

2012-04-01

The helium-tritium dating method is based on the analysis of tritium combined with its decay product, the lighter and rare 3He isotope. It was first suggested by Tolstikhin and Kamenskiy (1969) and has since been used in many groundwater studies. We applied the method to date groundwater recharged by bank filtration and former sewage irrigation onto sewage farms in Berlin, Germany, in order to assess the long-term persistence of several organic trace pollutants. In recent years, the occurrence of organic trace pollutants, such as pharmaceuticals and personal care products (PPCPs) as well as their metabolites, in the aquatic environment has been of increasing public and scientific interest (e.g. Schwarzenbach et al., 2006). In (urban) partly closed water cycles like Berlin, poorly biodegradable polar compounds may travel along the water path from wastewater via surface water to the raw water used for drinking water production (Reemtsma et al., 2006). In addition, raw or treated sewage irrigation onto sewage farms and/or agricultural land was common practice in Berlin until the 80s. Combined age dating and trace compound analysis revealed that several phenazone-type compounds (AMDOPH, AMPH, FAA and AAA) as well as a number of psychoactive compounds (meprobamate, pyrithyldione, primidone, and its metabolites phenobarbital and phenylethylmalonamide) are present in three decade old groundwater down gradient of a decommissioned sewage farm in Berlin, while a number of phenazone-type compounds (phenazone, propyphenazone, AMDOPH, AMPH) were present in decade-old bank filtrate. The results prove the long-term-persistence of the respective compounds under anoxic redox conditions, which are prevalent at the investigated sites. At the bank filtration sites, some of the compounds may regionally even be used as time markers for a certain infiltration period and reflect the surface water quality changes of the past few decades.

Utilizing thin-film solid-phase extraction to assess the effect of organic carbon amendments on the bioavailability of DDT and dieldrin to earthworms

USDA-ARS?s Scientific Manuscript database

Improved approaches are needed to rapidly and accurately assess the bioavailability of persistent, hydrophobic organic compounds in soils at contaminated sites. The performance of a thin-film solid-phase extraction (TF-SPE) assay using vials coated with ethylene vinyl acetate polymer was compared to...

Effects of defined mixtures of persistent organic pollutants (POPs) on multiple cellular responses in the human hepatocarcinoma cell line, HepG2, using high content analysis screening

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

Wilson, Jodie; Berntsen, Hanne Friis; Zimmer, Karin Elisabeth

Persistent organic pollutants (POPs) are toxic substances, highly resistant to environmental degradation, which can bio-accumulate and have long-range atmospheric transport potential. Most studies focus on single compound effects, however as humans are exposed to several POPs simultaneously, investigating exposure effects of real life POP mixtures on human health is necessary. A defined mixture of POPs was used, where the compound concentration reflected its contribution to the levels seen in Scandinavian human serum (total mix). Several sub mixtures representing different classes of POPs were also constructed. The perfluorinated (PFC) mixture contained six perfluorinated compounds, brominated (Br) mixture contained seven brominated compounds,more » chlorinated (Cl) mixture contained polychlorinated biphenyls and also p,p’-dichlorodiphenyldichloroethylene, hexachlorobenzene, three chlordanes, three hexachlorocyclohexanes and dieldrin. Human hepatocarcinoma (HepG2) cells were used for 2 h and 48 h exposures to the seven mixtures and analysis on a CellInsight™ NXT High Content Screening platform. Multiple cytotoxic endpoints were investigated: cell number, nuclear intensity and area, mitochondrial mass and membrane potential (MMP) and reactive oxygen species (ROS). Both the Br and Cl mixtures induced ROS production but did not lead to apoptosis. The PFC mixture induced ROS production and likely induced cell apoptosis accompanied by the dissipation of MMP. Synergistic effects were evident for ROS induction when cells were exposed to the PFC + Br mixture in comparison to the effects of the individual mixtures. No significant effects were detected in the Br + Cl, PFC + Cl or total mixtures, which contain the same concentrations of chlorinated compounds as the Cl mixture plus additional compounds; highlighting the need for further exploration of POP mixtures in risk assessment. - Highlights: • High content analysis (HCA) is a novel approach for determining toxicity of complex mixtures. • Multiple cytotoxic endpoints were investigated for defined mixtures of persistent organic pollutants (POPs). • POP mixtures are based on levels relevant to human exposure. • POP mixtures can increase ROS induction and impact mitochondrial health, which could result in apoptosis. • HCA can detect pre-lethal and reversible signs of cellular stress.« less

Odor and VOC Emissions from Pan Frying of Mackerel at Three Stages: Raw, Well-Done, and Charred

PubMed Central

Ahn, Jeong-Hyeon; Szulejko, Jan E.; Kim, Ki-Hyun; Kim, Yong-Hyun; Kim, Bo-Won

2014-01-01

Many classes of odorants and volatile organic compounds that are deleterious to our wellbeing can be emitted from diverse cooking activities. Once emitted, they can persist in our living space for varying durations. In this study, various volatile organic compounds released prior to and during the pan frying of fish (mackerel) were analyzed at three different cooking stages (stage 1 = raw (R), stage 2 = well-done (W), and stage 3 = overcooked/charred (O)). Generally, most volatile organic compounds recorded their highest concentration levels at stage 3 (O), e.g., 465 (trimethylamine) and 106 ppb (acetic acid). In contrast, at stage 2 (W), the lowest volatile organic compounds emissions were observed. The overall results of this study confirm that trimethylamine is identified as the strongest odorous compound, especially prior to cooking (stage 1 (R)) and during overcooking leading to charring (stage 3 (O)). As there is a paucity of research effort to measure odor intensities from pan frying of mackerel, this study will provide valuable information regarding the management of indoor air quality. PMID:25405596

Organic nitrogen storage in mineral soil: Implications for policy and management.

PubMed

Bingham, Andrew H; Cotrufo, M Francesca

2016-05-01

Nitrogen is one of the most important ecosystem nutrients and often its availability limits net primary production as well as stabilization of soil organic matter. The long-term storage of nitrogen-containing organic matter in soils was classically attributed to chemical complexity of plant and microbial residues that retarded microbial degradation. Recent advances have revised this framework, with the understanding that persistent soil organic matter consists largely of chemically labile, microbially processed organic compounds. Chemical bonding to minerals and physical protection in aggregates are more important to long-term (i.e., centuries to millennia) preservation of these organic compounds that contain the bulk of soil nitrogen rather than molecular complexity, with the exception of nitrogen in pyrogenic organic matter. This review examines for the first time the factors and mechanisms at each stage of movement into long-term storage that influence the sequestration of organic nitrogen in the mineral soil of natural temperate ecosystems. Because the factors which govern persistence are different under this newly accepted paradigm we examine the policy and management implications that are altered, such as critical load considerations, nitrogen saturation and mitigation consequences. Finally, it emphasizes how essential it is for this important but underappreciated pool to be better quantified and incorporated into policy and management decisions, especially given the lack of evidence for many soils having a finite capacity to sequester nitrogen. Published by Elsevier B.V.

EVIDENCE OF AIRBORNE CONTAMINATION OF WESTERN NORTH AMERICAN MOUNTAIN ECOSYSTEMS

EPA Science Inventory

There is emerging evidence that mountain ecosystems in the western USA are receiving deposition of persistent bioaccumulative toxicants with origins in North America and elsewhere in the Northern Hemisphere. The toxic materials include metals and organic compounds. Of particula...

SAR202 Genomes from the Dark Ocean Predict Pathways for the Oxidation of Recalcitrant Dissolved Organic Matter

PubMed Central

Landry, Zachary; Swan, Brandon K.; Herndl, Gerhard J.; Stepanauskas, Ramunas

2017-01-01

ABSTRACT Deep-ocean regions beyond the reach of sunlight contain an estimated 615 Pg of dissolved organic matter (DOM), much of which persists for thousands of years. It is thought that bacteria oxidize DOM until it is too dilute or refractory to support microbial activity. We analyzed five single-amplified genomes (SAGs) from the abundant SAR202 clade of dark-ocean bacterioplankton and found they encode multiple families of paralogous enzymes involved in carbon catabolism, including several families of oxidative enzymes that we hypothesize participate in the degradation of cyclic alkanes. The five partial genomes encoded 152 flavin mononucleotide/F420-dependent monooxygenases (FMNOs), many of which are predicted to be type II Baeyer-Villiger monooxygenases (BVMOs) that catalyze oxygen insertion into semilabile alicyclic alkanes. The large number of oxidative enzymes, as well as other families of enzymes that appear to play complementary roles in catabolic pathways, suggests that SAR202 might catalyze final steps in the biological oxidation of relatively recalcitrant organic compounds to refractory compounds that persist. PMID:28420738

Oligomers, organosulfates, and nitroxy organosulfates in rainwater identified by ultra-high resolution electrospray ionization FT-ICR mass spectrometry

NASA Astrophysics Data System (ADS)

Altieri, K. E.; Turpin, B. J.; Seitzinger, S. P.

2008-09-01

Wet deposition is an important removal mechanism for atmospheric organic matter, and a potentially important input for receiving ecosystems, yet less than 50% of rainwater organic matter is considered chemically characterized. Precipitation samples collected in New Jersey, USA, were analyzed by negative ion ultra-high resolution electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Elemental compositions of 552 unique molecular species were determined in the mass range 50 500 Da in the rainwater. Three main groups of organic compounds were identified: compounds containing carbon, hydrogen, and oxygen (CHO) only, sulfur (S) containing CHOS compounds, and S- and nitrogen containing CHONS compounds. Organic acids commonly identified in precipitation were detected, as well as linear alkylbenzene sulfonates, which are persistent pollutants commonly measured in river water, seawater, and sediments, but to our knowledge, not previously documented in atmospheric samples. Within the three main groups of compounds detected in the rainwater, oligomers, organosulfates, and nitroxy-organosulfates were identified. The majority of the compounds identified are products of atmospheric reactions and are known contributors to secondary organic aerosol (SOA) formed from gas phase, aerosol phase, and in-cloud reactions in the atmosphere. It is suggested that the large uncharacterized component of SOA is the main contributor to the large uncharacterized component of rainwater organic matter.

The role of hepatocyte nuclear factor 4-alpha in perfluorooctanoic and perfluorooctanesulfonic acid-induced hepatocellular dysfunction

EPA Science Inventory

Perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), chemicals present in a multitude of consumer products, are persistent organic pollutants. Both compounds induce hepatotoxic effects in rodents, including steatosis, hepatomegaly and liver cancer. The mechani...

Susceptibility of eastern oyster early life stages to road surface polycyclic aromatic hydrocarbons (PAHs).

DOT National Transportation Integrated Search

2012-06-01

Polycyclic aromatic hydrocarbons (PAHs) are a class of chemical compounds that are mostly : anthropogenic in nature, and they can become persistent organic contaminants in aquatic : ecosystems. Runoff from impervious surfaces is one of the many ways ...

Dichlorobenzene in ground water: Evidence for long-term persistence

USGS Publications Warehouse

Barber, L.B.

1988-01-01

Hydrologic and geochemical evidence were used to establish the long-term persistence of dichlorobenzene in ground water that has been contaminated from 50 years of rapid-infiltration sewage disposal. An extensive plume of dichlorobenzene extends more than 3,500 meters downgradient from the disposal beds, with concentrations of the combined isomers ranging from less than 0.01 to over 1.0 ??g/l. Based on estimates of maximum ground-water flow velocities, a minimum age of 20 years was established for the farthest downgradient zone of dichlorobenzene contamination. Branched-chained, alkylbenzenesulfonic acid surfactants, that were introduced into the ground water prior to 1966, occur along with dichlorobenzene in the downgradient part of the plume, further establish residence of the compounds in the aquifer for at least 20 years. Although dichlorobenzene can be biologically degraded under aerobic conditions, its persistence at this field site is attributed to the dynamics of the ground-water system. Denitrifying conditions, resulting from the degradation of organic compounds in the aquifer near the disposal beds, appear to have enhanced the persistence of dichlorobenzene, which is not degraded by anaerobic bacteria. Biological degradation of dichlorobenzene in the aerobic part of the plume downgradient from the source is probably limited by the paucity of a suitable organic-carbon substrate and the low concentrations of dissolved oxygen in the contaminated ground water.

Polychlorinated biphenyls: persistent pollutants with immunological, neurological, and endocrinological consequences.

PubMed

Crinnion, Walter J

2011-03-01

Polychlorinated biphenyls (PCBs) are considered "persistent organic pollutants;" fat-soluble compounds that bioaccumulate in individuals and bio-magnify in the food chain. PCBs were the first industrial compounds to experience a worldwide ban on production because of their potent toxicity. These compounds are still present in our food supply (fish, dairy, hamburger, and poultry being the most contaminated) and our bodies. Once in the body, they can cause long-term problems, especially for those exposed in utero. PCB bioaccumulation can lead to reduced infection fighting ability, increased rates of autoimmunity, cognitive and behavioral problems, and hypothyroidism. Some research also links PCBs to increased rates of type 2 diabetes. Testing is currently available for some of the most damaging PCBs. The testing compares individual levels to national reference values and can be interpreted to determine current exposure. Dietary measures can be enacted that will reduce PCB half-lives in humans by increasing excretion.

Pharmaceuticals and personal care products (PPCPs) are ecological disrupting compounds (EcoDC)

USGS Publications Warehouse

Richmond, Erinn; Grace, Michael; Kelly, John R.; Reisinger, Andrew; Rosi, Emma J.; Walters, David M.

2017-01-01

Pharmaceuticals and personal care products (PPCPs) are ubiquitous in freshwater ecosystems worldwide and are recognized as contaminants of concern. Currently, contaminants of concern are classified for their persistence, bioaccumulation, and toxicity (PBT criteria). PPCPs are not classified as persistent organic pollutants (POPs), although some PPCPs share characteristics similar to POPs. For example, PPCPs are known to be pseudopersistent due to constant discharge into the environment, often at low concentrations. At commonly reported environmental concentrations, PPCPs are rarely toxic, but the ability of these compounds to disrupt ecological processes and functions in freshwater ecosystems is often overlooked. Herein we briefly summarize recent studies highlighting the potential ecological effects of PPCPs, including effects on key ecological processes (e.g. primary productivity and community respiration), and we propose that appropriate screening for harmful effects of PPCPs in surface waters should be expanded to include Ecologically Disrupting Compounds (EcoDC) in addition to the established PBT criteria.

Review Article: Persistent organic pollutants and landfills - a review of past experiences and future challenges.

PubMed

Weber, Roland; Watson, Alan; Forter, Martin; Oliaei, Fardin

2011-01-01

The landfilling and dumping of persistent organic pollutants (POPs) and other persistent hazardous compounds, such as polychlorinated biphenyls (PCBs), hexachlorocyclohaxane (HCH), polybrominated diphenylether (PBDEs) or perfluorooctane sulfonic acid (PFOS) can have significant adverse environmental consequences. This paper reviews past experiences with such disposal practices and highlights their unsustainability due to the risks of contamination of ecosystems, the food chain, together with ground and drinking water supplies. The use and associated disposal of POPs have been occurring for over 50 years. Concurrent with the phase-out of some of the most hazardous chemicals, the production of new POPs, such as brominated and fluorinated compounds has increased since the 1990s. These latter compounds are commonly used in a wide range of consumer goods, and as consumer products reach the end of their useful lives, ultimately enter waste recycling and disposal systems, in particular at municipal landfills. Because of their very slow, or lack of degradability, POPs will persist in landfills for many decades and possibly centuries. Over these extended time periods engineered landfill systems and their liners are likely to degrade, thus posing a contemporary and future risk of releasing large contaminant loads to the environment. This review highlights the necessity for alternative disposal methods for POP wastes, including destruction or complete removal from potential environmental release. In addition to such end of pipe solutions a policy change in the use pattern of persistent toxic chemicals is inevitable. In addition, inventories for the location and quantity of POPs in landfills, together with an assessment of their threat to ecosystems, drinking water and food resources are identified as key measures to facilitate appropriate management of risks. Finally the challenges of POP wastes in transition/developing countries, the risk of increased leaching of POPs from landfills due to climate change, and the possible negative impact of natural attenuation processes are considered.

Epidemiology of endemic goitre in western Colombia

PubMed Central

Gaitan, E.; Merino, H.; Rodriguez, G.; Medina, P.; Meyer, J. D.; DeRouen, T. A.; MacLennan, R.

1978-01-01

This paper reports on recent epidemiological observations in western Colombia, which further demonstrate the presence of naturally-occurring goitrogens contaminating water supplies in areas where goitre persists despite prolonged and continuous iodine supplementation. 'Prospective' and 'cross-sectional' studies in 41 localities where the populations have been on a uniform and adequate iodine supplementation for the last 10-20 years indicate that, in the endemia of western Colombia, environmental factors other than nutritional iodine deficiency are responsible for differences in goitre prevalence. Further epidemiological studies to determine the causal factors for the persistence of the endemia established a correlation between the sources of drinking water and goitre prevalence rates. Organic compounds containing sulfur with marked thionamide-like antithyroid activity were isolated from water supplying endemic goitre districts, and results are presented supporting the hypothesis that sedimentary rocks rich in organic matter are the main source of water-borne goitrogens. Bacteriological investigations showed that the presence of Klebsiella pneumoniae in drinking water and bacterial concentration were related significantly with goitre prevalence only in the presence of other variables, particularly the presence of sedimentary rocks. In the light of these epidemiological observations and experimental studies it may be concluded that, at present, endemic goitre in western Colombia is not due to nutritional iodine deficiency, but that water supplies are contaminated with sulfur-bearing organic compounds with thionamide-like antithyroid activity most probably deriving from sedimentary rocks rich in organic matter and that these compounds are the main factor underlying the endemia. PMID:80287

Long-Term Fate of Organic Micropollutants in Sewage-Contaminated Groundwater

USGS Publications Warehouse

Barber, L.B.; Schroeder, M.P.; LeBlanc, D.R.

1988-01-01

Disposal of secondary sewage effluent by rapid infiltration has produced a plume of contaminated groundwater over 3500 m long near Falmouth, MA. Approximately 50 volatile organic compounds were detected and identified in the plume, at concentrations ranging from 10 ng/L to 500 ??g/L, by closed-loop stripping and purge- and-trap in conjuction with gas chromatography-mass spectrometry. The dominant contaminants were di-, tri- and tetrachloroethene, o- and p-dichlorobenzene, C1 to C6 alkylbenzenes, 2,6-di-tert-butylbenzoquinone, and several isomers of p-nonylphenol. The chloroethenes and chlorobenzenes had the same general distribution as chloride and boron and appear to be transported with little retardation. Less soluble compounds, such as nonylphenol and di-tert-butylbenzoquinone, appear to be retarded during subsurface transport by sorption processes. Although biodegradation of labile organic compounds occurs near the infiltration beds, many trace compounds, including chlorinated benzenes, alkylbenzenes, and aliphatic hydrocarbons, have persisted for more than 30 years in the aquifer.

Degradation of the Herbicide (2,4-Dichlorophenoxyacetic Acid) Using a Photoreactor with Exciplex Lamps

NASA Astrophysics Data System (ADS)

Vershinin, N. O.; Sokolova, I. V.; Tchaikovskaya, O. N.

2013-09-01

We present the results of tests of a compact flow-through reactor for neutralization of a broad class of persistent toxic compounds. As the toxicant we used the herbicide 2,4-dichlorophenoxyacetic acid, and we used exciplex lamps with different emission wave lengths (λ ~ 222 nm and 172 nm). We show the experimental decrease in the amount of organic compounds vs. irradiation time as obtained from the absorption spectra.

Polyfluoroalkyl Chemicals in the Serum and Milk of Breastfeeding Women.

EPA Science Inventory

Polyfluoroalkyl chemicals (PFCs) comprise a group of man-made organic compounds, some of which are persistent contaminants with developmental toxicity shown in laboratory animals. There is a paucity of human perinatal exposure data. The US EPA conducted a pilot study (Methods Adv...

Integrating nano- and microparticles in practical decontamination processes for water and sediments in a green technology approach

NASA Astrophysics Data System (ADS)

Eggen, Trine; Soran, Maria-Loredana

2015-12-01

Historically, pollution has been associated with heavy metals and hydrophobic persistent organic pollutants (POPs). This has changed. Today, legacy or emerging contaminants cover a vast number of compounds including industrial man-made chemicals, pesticides and pharmaceuticals in addition to inorganic elements and nanomaterials. These compounds are transferred to the environment via wastewater effluents and leachates and via sludge/biosolids such as fertilizers or soil amendments. Compared to previous POPs, today's legacy and emerging contaminants cover a broader spectrum of structures and properties, including a high number of persistent medium to highly water. For most emerging contaminants, neither the environmental transfer and residue nor the short- and long ecotoxicological and human adverse effects are known. Thus, it's time for precautionary acting and to replace conventional treatment processes originally designed for removal of organic matter and nutrients with processes suitable for removal of hazardous chemicals with a wide range of properties before entering water and terrestrial recipients.

Environmental levels, toxicity and human exposure to tributyltin (TBT)-contaminated marine environment. a review. b_antizar@hotmail.com.

PubMed

Antizar-Ladislao, Blanca

2008-02-01

Tributyltin (TBT) is a toxic chemical used for various industrial purposes such as slime control in paper mills, disinfection of circulating industrial cooling waters, antifouling agents, and the preservation of wood. Due to its widespread use as an antifouling agent in boat paints, TBT is a common contaminant of marine and freshwater ecosystems exceeding acute and chronic toxicity levels. TBT is the most significant pesticide in marine and freshwaters in Europe and consequently its environmental level, fate, toxicity and human exposure are of current concern. Thus, the European Union has decided to specifically include TBT compounds in its list of priority compounds in water in order to control its fate in natural systems, due to their toxic, persistent, bioaccumulative and endocrine disruptive characteristics. Additionally, the International Maritime Organization has called for a global treaty that bans the application of TBT-based paints starting 1 of January 2003, and total prohibition by 1 of January 2008. This paper reviews the state of the science regarding TBT, with special attention paid to the environmental levels, toxicity, and human exposure. TBT compounds have been detected in a number of environmental samples. In humans, organotin compounds have been detected in blood and in the liver. As for other persistent organic pollutants, dietary intake is most probably the main route of exposure to TBT compounds for the general population. However, data concerning TBT levels in foodstuffs are scarce. It is concluded that investigations on experimental toxicity, dietary intake, potential human health effects and development of new sustainable technologies to remove TBT compounds are clearly necessary.

BEHAVIORAL ASSESSMENTS OF LONG EVANS RATS FOLLOWING A 13 WEEK SUBCHRONIC TOLUENE EXPOSURE.

EPA Science Inventory

Whereas the acute effects of volatile organic compounds (VOCs) are relatively well understood, there is some controversy regarding the potential for persistent effects following long-term exposure. The current study sought to develop an animal model of subchronic exposure to VOCs...

Groundwater Sampling at ISCO Sites: Binary Mixtures of Volatile Organic Compounds and Persulfate

EPA Science Inventory

In-situ chemical oxidation involves the introduction of a chemical oxidant into the subsurface for the purpose of transforming ground-water contaminants into less harmful byproducts. Due to oxidant persistence, ground water samples collected at hazardous waste sites may contain o...

Persistent organic pollutants and histological lesions in Mayan catfish Ariopsis assimilis from the Bay of Chetumal, Mexico.

PubMed

Noreña-Barroso, E; Simá-Alvarez, R; Gold-Bouchot, G; Zapata-Pérez, O

2004-02-01

Livers of catfish (Ariopsis assimilis) from the Bay of Chetumal were analyzed for organochlorine compounds and hydrocarbons as part of a study to diagnose the environmental health of the Bay after a catfish mass mortality that occurred in 1996. The presence of histological lesions in several organs of the fish as result of chemical exposure was also evaluated. The concentrations of organic pollutants found in the Bay may be considered high if compared to the levels reported for sites affected by chemical pollution. High prevalences of cellular alteration histopathologies were found in liver, including hepatic tumors. The presence of some lesions may be related statistically to environmental pollution in the Bay, specially with chlorinated compounds.

Removal of bulk dissolved organic carbon (DOC) and trace organic compounds by bank filtration and artificial recharge.

PubMed

Grünheid, Steffen; Amy, Gary; Jekel, Martin

2005-09-01

Bank filtration and artificial recharge provide an important drinking water source to the city of Berlin. Due to the practice of water recycling through a semi-closed urban water cycle, the introduction of effluent organic matter (EfOM) and persistent trace organic pollutants in the drinking water is of potential concern. In the work reported herein, the research objectives are to study the removal of bulk and trace organics at bank filtration and artificial recharge sites and to assess important factors of influence for the Berlin area. The monthly analytical program is comprised of dissolved organic carbon (DOC), UV absorbance (UVA254), liquid chromatography with organic carbon detection (LC-OCD), differentiated adsorbable organic halogens (AOX) and single organic compound analysis of a few model compounds. More than 1 year of monitoring was conducted on observation wells located along the flowpaths of the infiltrating water at two field sites that have different characteristics regarding redox conditions, travel time, and travel distance. Two transects are highlighted: one associated with a bank filtration site dominated by anoxic/anaerobic conditions with a travel time of up to 4-5 months, and another with an artificial recharge site dominated by aerobic conditions with a travel time of up to 50 days. It was found that redox conditions and travel time significantly influence the DOC degradation kinetics and the efficiency of AOX and trace compound removal.

Atmospheric transport of persistent organic pollutants - development of a 3-d dynamical transport model covering the northern hemisphere

NASA Astrophysics Data System (ADS)

Hansen, K. M.; Christensen, J. H.; Geels, C.; Frohn, L. M.; Brandt, J.

2003-04-01

The Danish Eulerian Hemispheric Model (DEHM) is a 3-D dynamical atmospheric transport model originally developed to describe the atmospheric transport of sulphur, lead, and mercury to the Arctic. The model has been validated carefully for these compounds. A new version of DEHM is currently being developed to describe the atmospheric transport of persistent organic pollutants (POPs) which are toxic, lipophilic and bio-accumulating compounds showing great persistence in the environment. The model has a horizontal resolution of 150 km x 150 km and 18 vertical layers, and it is driven by meteorological data from the numerical weather prediction model MM5V2. During environmental cycling POPs can be deposited and re-emitted several times before reaching a final destination. A description of the exchange processes between the land/ocean surfaces and the atmosphere is included in the model to account for this multi-hop transport. The present model version describes the atmospheric transport of the pesticide alpha-hexachlorocyclohexane (alpha-HCH). Other POPs may be included when proper data on emissions and physical-chemical parameters becomes available. The model-processes and the first model results are presented. The atmospheric transport of alpha-HCH for the 1990s is well described by the model.

Unifying concepts linking dissolved organic matter composition to persistence in aquatic ecosystems

USGS Publications Warehouse

Kellerman, Anne M.; Guillemette, François; Podgorski, David C.; Aiken, George R.; Butler, Kenna D.; Spencer, Robert G. M.

2018-01-01

The link between composition and reactivity of dissolved organic matter (DOM) is central to understanding the role aquatic systems play in the global carbon cycle; yet, unifying concepts driving molecular composition have yet to be established. We characterized 37 DOM isolates from diverse aquatic ecosystems, including their stable and radiocarbon isotopes (δ13C-dissolved organic carbon (DOC) and Δ14C-DOC), optical properties (absorbance and fluorescence), and molecular composition (ultrahigh resolution mass spectrometry). Isolates encompassed end-members of allochthonous and autochthonous DOM from sites across the United States, the Pacific Ocean, and Antarctic lakes. Modern Δ14C-DOC and optical properties reflecting increased aromaticity, such as carbon specific UV absorbance at 254 nm (SUVA254), were directly related to polyphenolic and polycyclic aromatic compounds, whereas enriched δ13C-DOC and optical properties reflecting autochthonous end-members were positively correlated to more aliphatic compounds. Furthermore, the two sets of autochthonous end-members (Pacific Ocean and Antarctic lakes) exhibited distinct molecular composition due to differences in extent of degradation. Across all sites and end-members studied, we find a consistent shift in composition with aging, highlighting the persistence of certain biomolecules concurrent with degradation time.

ELECTROLYTIC DECHLORINATION OF 2-CHLOROBIPHENYL AT A PALLADIUM MODIFIED GRANULAR-GRAPHITE-PACKED ELECTRODE

EPA Science Inventory

Polychlorinated biphenyls (PCBs) and other chlorinated aromatic compounds are distributed in soils and sediments at over 400 sites in the USA. A national need exists for both in situ and ex situ methods to destroy these persistent organic pollutants in soils and sediments at ambi...

Analysis and advanced oxidation treatment of a persistent pharmaceutical compound in wastewater and wastewater sludge-carbamazepine.

PubMed

Mohapatra, D P; Brar, S K; Tyagi, R D; Picard, P; Surampalli, R Y

2014-02-01

Pharmaceutically active compounds (PhACs) are considered as emerging environmental problem due to their continuous input and persistence to the aquatic ecosystem even at low concentrations. Among them, carbamazepine (CBZ) has been detected at the highest frequency, which ends up in aquatic systems via wastewater treatment plants (WWTPs) among other sources. The identification and quantification of CBZ in wastewater (WW) and wastewater sludge (WWS) is of major interest to assess the toxicity of treated effluent discharged into the environment. Furthermore, WWS has been subjected for re-use either in agricultural application or for the production of value-added products through the route of bioconversion. However, this field application is disputable due to the presence of these organic compounds and in order to protect the ecosystem or end users, data concerning the concentration, fate, behavior as well as the perspective of simultaneous degradation of these compounds is urgently necessary. Many treatment technologies, including advanced oxidation processes (AOPs) have been developed in order to degrade CBZ in WW and WWS. AOPs are technologies based on the intermediacy of hydroxyl and other radicals to oxidize recalcitrant, toxic and non-biodegradable compounds to various by-products and eventually to inert end products. The purpose of this review is to provide information on persistent pharmaceutical compound, carbamazepine, its ecological effects and removal during various AOPs of WW and WWS. This review also reports the different analytical methods available for quantification of CBZ in different contaminated media including WW and WWS. © 2013 Elsevier B.V. All rights reserved.

Modification of PBDEs (BDE-15, BDE-47, BDE-85 and BDE-126) biological toxicity, bio-concentration, persistence and atmospheric long-range transport potential based on the pharmacophore modeling assistant with the full factor experimental design.

PubMed

Jiang, Long; Li, Yu

2016-04-15

In this study, the properties of AhR binding affinity, bio-concentration factor, half-life and vapor pressure were selected as the typical indicators of biological toxicity, bio-concentration, persistence and atmospheric long-range transport potential for polybrominated diphenyl ethers (PBDEs), respectively. A three-dimensional pharmacophore modeling assistant with a full factor experimental design for each property was used to reveal the significant pharmacophore features and the substituent effects to obtain reasonable modified schemes for the selected target PBDEs. Finally, the performances of the persistent organic pollutant (POP) properties, the synthesis feasibility and the fire resistance of the modified compounds were evaluated. The most influential pharmacophore feature for all POP properties was the hydrophobic group, especially the vinyl and propyl groups. Modified compounds with two additional hydrophobic groups exhibited a better regulatory performance. The average reduction in the proportions of the four POP properties for the modified compounds (except for 3-phenyl-BDE-15) was 70.60%, 52.44%, 47.04% and 70.88%. In addition, the energy and the C-Br bond dissociation enthalpy of the four typical PBDEs were higher than those of the modified compounds (except for 3-phenyl-BDE-15), indicating the synthesis feasibility and the lower energy barrier of the modified compounds to release Br free radicals to provide fire resistance. Copyright © 2015 Elsevier B.V. All rights reserved.

Integrated Risk Index of Chemical Aquatic Pollution (IRICAP): case studies in Iberian rivers.

PubMed

Fàbrega, Francesc; Marquès, Montse; Ginebreda, Antoni; Kuzmanovic, Maja; Barceló, Damià; Schuhmacher, Marta; Domingo, José L; Nadal, Martí

2013-12-15

The hazard of chemical compounds can be prioritized according to their PBT (persistence, bioaccumulation, toxicity) properties by using Self-Organizing Maps (SOM). The objective of the present study was to develop an Integrated Risk Index of Chemical Aquatic Pollution (IRICAP), useful to evaluate the risk associated to the exposure of chemical mixtures contained in river waters. Four Spanish river basins were considered as case-studies: Llobregat, Ebro, Jucar and Guadalquivir. A SOM-based hazard index (HI) was estimated for 205 organic compounds. IRICAP was calculated as the product of the HI by the concentration of each pollutant, and the results of all substances were aggregated. Finally, Pareto distribution was applied to the ranked lists of compounds in each site to prioritize those chemicals with the most significant incidence on the IRICAP. According to the HI outcomes, perfluoroalkyl substances, as well as specific illicit drugs and UV filters, were among the most hazardous compounds. Xylazine was identified as one of the chemicals with the highest contribution to the total IRICAP value in the different river basins, together with other pharmaceutical products such as loratadine and azaperol. These organic compounds should be proposed as target chemicals in the implementation of monitoring programs by regulatory organizations. Copyright © 2013 Elsevier B.V. All rights reserved.

Star-Shaped Conjugated Systems

PubMed Central

Detert, Heiner; Lehmann, Matthias; Meier, Herbert

2010-01-01

The present review deals with the preparation and the properties of star-shaped conjugated compounds. Three, four or six conjugated arms are attached to cross-conjugated cores, which consist of single atoms (B, C+, N), benzene or azine rings or polycyclic ring systems, as for example triphenylene or tristriazolotriazine. Many of these shape-persistent [n]star compounds tend to π-stacking and self-organization, and exhibit interesting properties in materials science: Linear and non-linear optics, electrical conductivity, electroluminescence, formation of liquid crystalline phases, etc.

Long-term monitoring of persistent organic pollutants (POPs) at the Norwegian Troll station in Dronning Maud Land, Antarctica

NASA Astrophysics Data System (ADS)

Kallenborn, R.; Breivik, K.; Eckhardt, S.; Lunder, C. R.; Manø, S.; Schlabach, M.; Stohl, A.

2013-07-01

A first long-term monitoring of selected persistent organic pollutants (POPs) in Antarctic air has been conducted at the Norwegian research station Troll (Dronning Maud Land). As target contaminants 32 PCB congeners, α- and γ-hexachlorocyclohexane (HCH), trans- and cis-chlordane, trans- and cis-nonachlor, p,p'- and o,p-DDT, DDD, DDE as well as hexachlorobenzene (HCB) were selected. The monitoring program with weekly samples taken during the period 2007-2010 was coordinated with the parallel program at the Norwegian Arctic monitoring site (Zeppelin mountain, Ny-Ålesund, Svalbard) in terms of priority compounds, sampling schedule as well as analytical methods. The POP concentration levels found in Antarctica were considerably lower than Arctic atmospheric background concentrations. Similar to observations for Arctic samples, HCB is the predominant POP compound, with levels of around 22 pg m-3 throughout the entire monitoring period. In general, the following concentration distribution was found for the Troll samples analyzed: HCB > Sum HCH > Sum PCB > Sum DDT > Sum chlordanes. Atmospheric long-range transport was identified as a major contamination source for POPs in Antarctic environments. Several long-range transport events with elevated levels of pesticides and/or compounds with industrial sources were identified based on retroplume calculations with a Lagrangian particle dispersion model (FLEXPART).

Dioxins and dioxin-like compounds in composts and digestates from European countries as determined by the in vitro bioassay and chemical analysis.

PubMed

Beníšek, Martin; Kukučka, Petr; Mariani, Giulio; Suurkuusk, Gert; Gawlik, Bernd M; Locoro, Giovanni; Giesy, John P; Bláha, Luděk

2015-03-01

Aerobic composting and anaerobic digestion plays an important role in reduction of organic waste by transforming the waste into humus, which is an excellent soil conditioner. However, applications of chemical-contaminated composts on soils may have unwanted consequences such as accumulation of persistent compounds and their transfer into food chains. The present study investigated burden of composts and digestates collected in 16 European countries (88 samples) by the compounds causing dioxin-like effects as determined by use of an in vitro transactivation assay to quantify total concentrations of aryl hydrocarbon receptor-(AhR) mediated potency. Measured concentrations of 2,3,7,8-Tetrachlorodibeno-p-dioxin (2,3,7,8-TCDD) equivalents (TEQbio) were compared to concentrations of polycyclic aromatic hydrocarbons (PAHs) and selected chlorinated compounds, including polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), co-planar polychlorinated biphenyls (PCBs), indicator PCB congeners and organochlorine pesticides (OCPs). Median concentrations of TEQbio (dioxin-like compounds) determined by the in vitro assay in crude extracts of various types of composts ranged from 0.05 to 1.2 with a maximum 8.22μg (TEQbio)kg(-1) dry mass. Potencies were mostly associated with less persistent compounds such as PAHs because treatment with sulfuric acid removed bioactivity from most samples. The pan-European investigation of contamination by organic contaminants showed generally good quality of the composts, the majority of which were in compliance with conservative limits applied in some countries. Results demonstrate performance and added value of rapid, inexpensive, effect-based monitoring, and points out the need to derive corresponding effect-based trigger values for the risk assessment of complex contaminated matrices such as composts. Copyright © 2014 Elsevier Ltd. All rights reserved.

Identifying new persistent and bioaccumulative organics among chemicals in commerce II: pharmaceuticals.

PubMed

Howard, Philip H; Muir, Derek C G

2011-08-15

The goal of this study was to identify commercial pharmaceuticals that might be persistent and bioaccumulative (P&B) and that were not being considered in current wastewater and aquatic environmental measurement programs. We developed a database of 3193 pharmaceuticals from two U.S. Food and Drug Administration (FDA) databases and some lists of top ranked or selling drugs. Of the 3193 pharmaceuticals, 275 pharmaceuticals have been found in the environment and 399 pharmaceuticals were, based upon production volumes, designated as high production volume (HPV) pharmaceuticals. All pharmaceuticals that had reported chemical structures were evaluated for potential bioaccumulation (B) or persistence (P) using quantitative structure property relationships (QSPR) or scientific judgment. Of the 275 drugs detected in the environment, 92 were rated as potentially bioaccumulative, 121 were rated as potentially persistent, and 99 were HPV pharmaceuticals. After removing the 275 pharmaceuticals previously detected in the environment, 58 HPV compounds were identified that were both P&B and 48 were identified as P only. Of the non-HPV compounds, 364 pharmaceuticals were identified that were P&B. This study has yielded some interesting and probable P&B pharmaceuticals that should be considered for further study.

Evaluation of the persistence of transformation products from ozonation of trace organic compounds - a critical review.

PubMed

Hübner, Uwe; von Gunten, Urs; Jekel, Martin

2015-01-01

Ozonation is an efficient treatment system to reduce the concentration of trace organic compounds (TrOCs) from technical aquatic systems such as drinking water, wastewater and industrial water, etc. Although it is well established that ozonation generally improves the removal of organic matter in biological post-treatment, little is known about the biodegradability of individual transformation products resulting from ozonation of TrOCs. This publication provides a qualified assessment of the persistence of ozone-induced transformation products based on a review of published product studies and an evaluation of the biodegradability of transformation products with the biodegradability probability program (BIOWIN) and the University of Minnesota Pathway Prediction System (UM-PPS). The oxidation of TrOCs containing the four major ozone-reactive sites (olefins, amines, aromatics and sulfur-containing compounds) follows well described reaction pathways leading to characteristic transformation products. Assessment of biodegradability revealed a high sensitivity to the formed products and hence the ozone-reactive site present in the target compound. Based on BIOWIN, efficient removal can be expected for products from cleavage of olefin groups and aromatic rings. In contrast, estimations and literature indicate that hydroxylamines and N-oxides, the major products from ozonation of secondary and tertiary amines are not necessarily better removed in biological post-treatment. According to UM-PPS, degradation of these products might even occur via reformation of the corresponding amine. Some product studies with sulfide-containing TrOCs showed a stoichiometric formation of sulfoxides from oxygen transfer reactions. However, conclusions on the fate of transformation products in biological post-treatment cannot be drawn based on BIOWIN and UM-PPS.

CHANGES IN MRNA EXPRESSION PROFILES IN RAT CORTEX AND STRIATUM FOLLOWING SUB CHRONIC TOLUENE EXPOSURE.

EPA Science Inventory

Toluene, a volatile organic compound (VOC) used in many commercial products, is a ubiquitous air pollutant and therefore of interest to many EPA regulatory programs. A primary concern for toluene and other VOC’s is the potential for persistent neurotoxic effects from long term e...

PERSISTENT EFFECTS OF REPEATED INHALATION OF TOLUENE: 4 WEEKS VS. 13 WEEKS.

EPA Science Inventory

Understanding and predicting the extent of neurotoxic damage from repeated exposure to volatile organic compounds (VOCs) is a problem for many EPA programs. Eighty adult, male Long-Evans rats inhaled toluene (0, 10, 100, or 1000 ppm) 6 hr/day, 5 days/week for 4 weeks in a systema...

Contaminated environments in the subsurface and bioremediation: organic contaminants.

PubMed

Holliger, C; Gaspard, S; Glod, G; Heijman, C; Schumacher, W; Schwarzenbach, R P; Vazquez, F

1997-07-01

Due to leakages, spills, improper disposal and accidents during transport, organic compounds have become subsurface contaminants that threaten important drinking water resources. One strategy to remediate such polluted subsurface environments is to make use of the degradative capacity of bacteria. It is often sufficient to supply the subsurface with nutrients such as nitrogen and phosphorus, and aerobic treatments are still dominating. However, anaerobic processes have advantages such as low biomass production and good electron acceptor availability, and they are sometimes the only possible solution. This review will focus on three important groups of environmental organic contaminants: hydrocarbons, chlorinated and nitroaromatic compounds. Whereas hydrocarbons are oxidized and completely mineralized under anaerobic conditions in the presence of electron acceptors such as nitrate, iron, sulfate and carbon dioxide, chlorinated and nitroaromatic compounds are reductively transformed. For the aerobic often persistent polychlorinated compounds, reductive dechlorination leads to harmless products or to compounds that are aerobically degradable. The nitroaromatic compounds are first reductively transformed to the corresponding amines and can subsequently be bound to the humic fraction in an aerobic process. Such new findings and developments give hope that in the near future contaminated aquifers can efficiently be remediated, a prerequisite for a sustainable use of the precious-subsurface drinking water resources.

Concentration/time-dependent dissipation, partitioning and plant accumulation of hazardous current-used pesticides and 2-hydroxyatrazine in sand and soil.

PubMed

Neuwirthová, Natália; Bílková, Zuzana; Vašíčková, Jana; Hofman, Jakub; Bielská, Lucie

2018-07-01

The dissipation, partitioning dynamics and biouptake was measured for selected hazardous current-used pesticides (conazole fungicides: epoxiconazole, flusilazole, tebuconazole; prochloraz, chlorpyrifos, pendimethalin) and for a transformation product (2-hydroxyatrazine) in agricultural soil and quartz sand as representatives of a real and a worst-case scenario. Dissipation, uptake to Lactuca sativa and the freely dissolved concentration along with the organic carbon-normalized sorption coefficients (K oc ) were determined on days 12, 40, and 90 following the application of compounds at three fortification levels (0.1-1.0-10 mg/kg). Conazole fungicides showed similar dissipation patterns and were more persistent in soil than prochloraz, chlorpyrifos and pendimethalin. 2-Hydroxyatrazine showed a concentration-depended decrease in persistency in soil. Lettuce roots were shown to accumulate higher amounts than shoots where the extent of root uptake was driven by compound partitioning. This was evidenced by the ability of freely dissolved concentration (C free ) to reliably (r 2  = 0.94) predict root uptake. Concentration in leaves did not exceed the maximum residue levels (MRLs) for lettuce, which was likely given by the low root-to-shoot translocation factors (TFs) of the tested compounds varying between 0.007 and 0.14. K oc values were in the range of literature values. Sorption to soil was higher than to sand for all compounds, yet following the K oc dynamics compounds did not appear to be sequestered in soil with increasing residence time. From these results, it follows that the tested compounds may persist in soil but since they did not accumulate in lettuce above MRLs, contamination of the food web is unlikely. Copyright © 2018 Elsevier Ltd. All rights reserved.

Strengthen the collaboration between the River Basin Management Organization of China and International Environmental Specimen Bank Group.

PubMed

Tan, Lingzhi; Liu, Hui; Shu, Jinxiang; Xia, Fan

2015-02-01

Several types of emerging organic contaminants were investigated in many recent researches, such as persistent toxic substance (PTS), persistent organic pollutants (POPs), endocrine disrupters (EDs), and volatile organic compounds (VOCs). But the Chinese country standard detection methods of emerging organic pollutants were not developed with the dramatic increasing of the organic substances production. Hence, it is necessary to obtain the latest informations about the long-term storage of representative environmental specimens, which could provide scientific basis for environmental management and environmental decision-making of the water resources protection and management organization. As the significant water resource conservation organization, the Water Environment Monitoring Center of Yangtze River Basin is experienced in water environmental monitoring and records many useful water resources and environment informations. It is also our responsibility to monitor all the pollutants in water environment of the Yangtze River valley, especially the emerging organic contaminants. Meanwhile, the International Environmental Specimen Bank (IESB) accumulates lots environmental organic pollution specimens and plays a significant role in environmental monitoring. Thus, the collaboration between the two parties will be greatly helpful for each further researches and monitoring work of organic contaminants in Yangtze River Basin.

Persistent organic contaminants in Saharan dust air masses in West Africa, Cape Verde and the eastern Caribbean

USGS Publications Warehouse

Garrison, Virginia H.; Majewski, Michael S.; Foreman, William T.; Genualdi, Susan A.; Mohammed, Azad; Massey Simonich, Stacy L.

2014-01-01

Anthropogenic semivolatile organic compounds (SOCs) that persist in the environment, bioaccumulate, are toxic at low concentrations, and undergo long-range atmospheric transport (LRT) were identified and quantified in the atmosphere of a Saharan dust source region (Mali) and during Saharan dust incursions at downwind sites in the eastern Caribbean (U.S. Virgin Islands, Trinidad and Tobago) and Cape Verde. More organochlorine and organophosphate pesticides (OCPPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyl (PCB) congeners were detected in the Saharan dust region than at downwind sites. Seven of the 13 OCPPs detected occurred at all sites: chlordanes, chlorpyrifos, dacthal, dieldrin, endosulfans, hexachlorobenzene (HCB), and trifluralin. Total SOCs ranged from 1.9–126 ng/m3 (mean = 25 ± 34) at source and 0.05–0.71 ng/m3 (mean = 0.24 ± 0.18) at downwind sites during dust conditions. Most SOC concentrations were 1–3 orders of magnitude higher in source than downwind sites. A Saharan source was confirmed for sampled air masses at downwind sites based on dust particle elemental composition and rare earth ratios, atmospheric back trajectory models, and field observations. SOC concentrations were considerably below existing occupational and/or regulatory limits; however, few regulatory limits exist for these persistent organic compounds. Long-term effects of chronic exposure to low concentrations of SOCs are unknown, as are possible additive or synergistic effects of mixtures of SOCs, biologically active trace metals, and mineral dust particles transported together in Saharan dust air masses.

The deep-sea as a final global sink of semivolatile persistent organic pollutants? Part I: PCBs in surface and deep-sea dwelling fish of the north and south Atlantic and the Monterey Bay Canyon (California).

PubMed

Froescheis, O; Looser, R; Cailliet, G M; Jarman, W M; Ballschmiter, K

2000-03-01

The understanding of the global environmental multiphase distribution of persistent organic pollutants (POPs) as a result of the physico-chemical properties of the respective compounds is well established. We have analysed the results of a vertical transport of POPs from upper water layers (0-200 m) to the deepwater region (> 800 m) in terms of the contamination of the biophase in both water layers. The contents of persistent organochlorine compounds like polychlorinated biphenyls (PCBs) in fish living in the upper water layers of the North Atlantic and the South Atlantic, and at the continental shelf of California (Marine Sanctuary Monterey Bay and its deep-sea Canyon) are compared to the levels in deep-sea or bottom dwelling fish within the same geographic area. The deep-sea biota show significantly higher burdens as compared to surface-living species of the same region. There are also indications for recycling processes of POPs--in this case the PCBs--in the biophase of the abyss as well. It can be concluded that the bio- and geo phase of the deep-sea may act similarly as the upper horizons of forest and grasslands on the continents as an ultimate global sink for POPs in the marine environment.

Sediments indicate the continued use of banned antifouling compounds.

PubMed

Egardt, Jenny; Nilsson, Per; Dahllöf, Ingela

2017-12-15

Antifouling paints are widely used to avoid organisms settling on boat hulls. The active ingredients in the paints have differed over the years where lead, TBT, irgarol and diuron have been deemed too harmful to non-target organisms and subsequently been banned within the EU. Most of these compounds however are persistent in the environment and can cause problems long after they are deposited. We have examined if present-day and banned substances used in antifouling paints can be found in sediments in a national park on the Swedish west coast. Sampled locations include waterways, natural harbours and small marinas for leisure crafts to investigate if number of visiting boats affect the concentration of antifouling compounds in sediments. Few significant differences were found when comparing the different locations types, suggesting that overall boat presence is more important than specific mooring sites, however, several banned antifouling compounds were found in the surface sediments. Copyright © 2017 Elsevier Ltd. All rights reserved.

TOOL FOR MONITORING HYDROPHILIC CONTAMINANTS ...

EPA Pesticide Factsheets

Global emissions of persistent bioconcentratable organic chemicals have resulted in a wide range of adverse ecological effects. Consequently, industry was led to develop less persistent, more water soluble, polar or hydrophilic organic compounds (HpOCs), which generally have low bioconcentration factors. However, evidence is growing that the large fluxes of these seemingly more environmentally friendly compounds (e.g., pesticides, prescription and non-prescription drugs, personal care and common consumer products, industrial and domestic-use chemicals and their degradation products) into aquatic systems on a world-wide basis may be responsible for incidents of acute toxicity and sub-lethal chronic abnormalities. These adverse effects include altered behavior, neurotoxicity, and severely impaired reproduction. Furthermore, the presence of these HpOCs likely plays a major role in the endocrine disrupting effects of complex mixtures of chemicals present in aquatic environments. In regard to physiological effects, pharmaceuticals are of particular concern because they are designed to elicit diverse pharmacological responses at very low doses. Unfortunately, the effects of this class of HpOCs on non-target, aquatic organisms are largely unknown. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are

Organochlorine pesticides, HCB, and PCBs in human milk in Poland

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

Czaja, K.; Ludwicki, J.K.; Goralczyk, K.

1997-05-01

Persistent organochlorine compounds were used in agriculture and industry for years. Their ability to accumulate in organisms constituting links of the food chain and a unique chemical stability made them a hazardous environmental contaminants. The metabolism and excretion of chlorinated hydrocarbons is a very slow process. One of the most important means of elimination such compounds from the woman`s body is lactation. Consequently, human milk has occasionally a significant concentration of organochlorine compounds. Such compounds are identified in women`s milk all over the world. The objective of this study was to identify organochlorine pesticides, HCB, and PCBs concentrations in humanmore » milk in Poland by comparing more and less industrialized regions. 15 refs., 3 tabs.« less

The study of interaction between PFOA/PFOS and uracil by topology quality and spectroscopic analysis

NASA Astrophysics Data System (ADS)

Xu, Hui-Ying; Zhu, Jian-Qing; Wang, Wei; Xu, Xiao-Lu; Lu, Yin

2014-02-01

It has been established that perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) can be considered as emerging persistent organic pollutants. In recent years, there was increasing distribution of PFOA/PFOS in environmental systems, and accumulation and toxic effects of PFOA/PFOS in human body. In this paper, quantum chemistry methods were employed to study the interaction between perfluorinated organic pollutants and base (uracil). The results showed that there were four stable binding modes between the two perfluorinated compounds with uracil, especially the second mode which caused the most detrimental physiological functional response. NBO analysis showed that reactive hydrogen in the two perfluorinated compounds had the greatest effect on the hydrogen bond. The nature of the hydrogen bond formed between the two perfluorinated compounds and base was investigated using the AIM theory. The changes of spectroscopic properties in complexes were analyzed by IR and NMR spectra.

Investigation of extractable organic compounds in deep-sea hydrothermal vent fluids along the Mid-Atlantic Ridge

NASA Astrophysics Data System (ADS)

McCollom, Thomas M.; Seewald, Jeffrey S.; German, Christopher R.

2015-05-01

The possibility that deep-sea hydrothermal vents may contain organic compounds produced by abiotic synthesis or by microbial communities living deep beneath the surface has led to numerous studies of the organic composition of vent fluids. Most of these studies have focused on methane and other light hydrocarbons, while the possible occurrence of more complex organic compounds in the fluids has remained largely unstudied. To address this issue, the presence of higher molecular weight organic compounds in deep-sea hydrothermal fluids was assessed at three sites along the Mid-Atlantic Ridge that span a range of temperatures (51 to >360 °C), fluid compositions, and host-rock lithologies (mafic to ultramafic). Samples were obtained at several sites within the Lucky Strike, Rainbow, and Lost City hydrothermal fields. Three methods were employed to extract organic compounds for analysis, including liquid:liquid extraction, cold trapping on the walls of a coil of titanium tubing, and pumping fluids through cartridges filled with solid phase extraction (SPE) sorbents. The only samples to consistently yield high amounts of extractable organic compounds were the warm (51-91 °C), highly alkaline fluids from Lost City, which contained elevated concentrations of C8, C10, and C12n-alkanoic acids and, in some cases, trithiolane, hexadecanol, squalene, and cholesterol. Collectively, the C8-C12 acids can account for about 15% of the total dissolved organic carbon in the Lost City fluids. The even-carbon-number predominance of the alkanoic acids indicates a biological origin, but it is unclear whether these compounds are derived from microbial activity occurring within the hydrothermal chimney proximal to the site of fluid discharge or are transported from deeper within the system. Hydrothermal fluids from the Lucky Strike and Rainbow fields were characterized by an overall scarcity of extractable dissolved organic compounds. Trace amounts of aromatic hydrocarbons including phenanthrenes and benzothiophene were the only compounds that could be identified as indigenous components of these fluids. Although hydrocarbons and fatty acids were observed in some samples, those compounds were likely derived from particulate matter or biomass entrained during fluid collection. In addition, extracts of some fluid samples from the Rainbow field were found to contain an unresolved complex mixture (UCM) of organic compounds. This UCM shared some characteristics with organic matter extracted from bottom seawater, suggesting that the organic matter observed in these samples might represent seawater-derived compounds that had persisted, albeit with partial alteration, during circulation through the hydrothermal system. While there is considerable evidence that Rainbow and Lost City vent fluids contain methane and other light hydrocarbons produced through abiotic reduction of inorganic carbon, we found no evidence for more complex organic compounds with an abiotic origin in the same fluids.

Fragmentation as a condition for persistence - exploring a new perspective of mineral-organic interactions

NASA Astrophysics Data System (ADS)

Kleber, M.; Liu, S. Y.; Keiluweit, M.; Nico, P. S.; Ahmed, M.

2012-12-01

High radiocarbon ages (centennial to millennial) of soil organic matter tend to occur in soils with high proportions of reactive, hydroxylated minerals, including andisols, spodosols and oxisols. This indicates that the most reactive mineral surfaces, i.e. those that should in theory be particularly efficient in promoting transformations of organic matter are among the most powerful in protecting organic matter against decomposition on long time scales. The easiest way to reconcile this apparent paradox is to assume that organic compounds become fragmented upon contact with minerals, thereby generating fragmentation products which in turn are more likely to become preserved within the soil fabric than their precursor molecules. Here we use Vacuum Ultraviolet - Post Ionisation -Mass Spectroscopy (VUV-PI-MS) in combination with thermal and laser desorption to show how organic compounds undergo complete fragmentation upon contact with mineral surfaces. Fragmentation patterns were generally different between oxidic minerals and minerals belonging to the phyllosilicate group. Also, desorption from phyllosilicates generally required significantly higher energies than desorption from oxide phases. Our investigation suggests that, at low energy levels, breakdown and fragmentation is a probably major outcome of mineral-organic interactions. This observation supports a new model for the role of mineral-organic interactions in the preservation of organic compounds in the environment: mineral-induced fragmentation as a prerequisite for long term protection against decomposition.

Contribution of low molecular weight phenols to bitter taste and mouthfeel properties in red wines.

PubMed

Gonzalo-Diago, Ana; Dizy, Marta; Fernández-Zurbano, Purificación

2014-07-01

The aim of this study was to explore the relationship between low molecular weight compounds present in wines and their sensory contribution. Six young red wines were fractionated by gel permeation chromatography and subsequently each fraction obtained was separated from sugars and acids by solid phase extraction. Wines and both fractions were in-mouth evaluated by a trained sensory panel and UPLC-MS analyses were performed. The lack of ethanol and proanthocyanidins greatly increased the acidity perceived. The elimination of organic acids enabled the description of the samples, which were evaluated as bitter, persistent and slightly astringent. Coutaric acid and quercetin-3-O-rutinoside appear to be relevant astringent compounds in the absence of proanthocyanidins. Bitter taste was highly correlated with the in-mouth persistence. A significant predictive model for bitter taste was built by means of PLSR. Further research must be carried out to validate the sensory contribution of the compounds involved in bitterness and astringency and to verify the sensory interactions observed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Multidrug Efflux Transporters Limit Accumulation of Inorganic, but Not Organic, Mercury in Sea Urchin Embryos

PubMed Central

Bošnjak, Ivana; Uhlinger, Kevin R.; Heim, Wesley; Smital, Tvrtko; Franekić-Čolić, Jasna; Coale, Kenneth; Epel, David; Hamdoun, Amro

2011-01-01

Mercuric compounds are persistent global pollutants that accumulate in marine organisms and in humans who consume them. While the chemical cycles and speciation of mercury in the oceans are relatively well described, the cellular mechanisms that govern which forms of mercury accumulate in cells and why they persist are less understood. In this study we examined the role of multidrug efflux transport in the differential accumulation of inorganic (HgCl2) and organic (CH3HgCl) mercury in sea urchin (Strongylocentrotus purpuratus) embryos. We found that inhibition of MRP/ABCC-type transporters increases intracellular accumulation of inorganic mercury but had no effect on accumulation of organic mercury. Similarly, pharmacological inhibition of metal conjugating enzymes by ligands GST/GSH significantly increases this antimitotic potency of inorganic mercury, but had no effect on the potency of organic mercury. Our results point to MRP-mediated elimination of inorganic mercury conjugates as a cellular basis for differences in the accumulation and potency of the two major forms of mercury found in marine environments. PMID:19924972

Persistent organic pollutants and polycyclic aromatic hydrocarbons in penguins of the genus Pygoscelis in Admiralty Bay - An Antarctic specially managed area.

PubMed

Montone, Rosalinda C; Taniguchi, Satie; Colabuono, Fernanda I; Martins, César C; Cipro, Caio Vinícius Z; Barroso, Hileia S; da Silva, Josilene; Bícego, Márcia C; Weber, Rolf R

2016-05-15

Persistent organic pollutants were assessed in fat samples of the Gentoo (Pygoscelis papua), Chinstrap (Pygoscelis antarcticus) and Adélie (Pygoscelis adeliae) penguins collected during the austral summers of 2005/06 and 2006/07 in Admiralty Bay, King George Island, Antarctica. The predominant organic pollutants were PCB (114 to 1115), polycyclic aromatic hydrocarbons (PAHs) (60.1 to 238.7), HCB (<0.3 to 132.2) and BDE-47 (<1.0 to 10.7) in ng g(-1) wet weight. The mean concentrations of the majority of organic pollutants were similar among the three species of penguins. Chicks of all three species showed similar profiles of PCB congeners, with predominance of lower chlorinated compounds. The distribution of PAHs was similar in all birds, with a predominance of naphthalene and alkyl-naphthalene, which are the main constituents of arctic diesel fuel. These data contribute to the monitoring of the continued exposure to organic pollutants in the Antarctic biota. Copyright © 2016 Elsevier Ltd. All rights reserved.

Persistent toxic substances: sources, fates and effects.

PubMed

Wong, Ming H; Armour, Margaret-Ann; Naidu, Ravi; Man, Ming

2012-01-01

Persistent toxic substances (PTS) include the Stockholm persistent organic pollutants, like dichlorodiphenyltrichloroethane, polychlorinated biphenyls, dioxin/furan, etc., and organometallic compounds, like organomercury, organotin, and organolead, which all share the same characteristics of being persistent, toxic, bioaccumulative, and able to travel long distances through different media. The adverse health effects of some of the emerging chemicals like pentabromodiphenyl ether, bisphenol A, and di(2-ethylhexyl)phthalate, which are widely used in daily appliances (e.g., TVs, computers, mobile phones, plastic baby bottles), have become a public health concern due to more evidence now available showing their adverse effects like disturbance of the endocrine system and cancer. This article is an attempt to review the current status of PTS in our environment, citing case studies in China and North America, and whether our existing drinking water treatment and wastewater treatment processes are adequate in removing them from water. Some management issues of these emerging chemicals of concern are also discussed.

Molecular characterization of organic matter mobilized from Bangladeshi aquifer sediment: tracking carbon compositional change during microbial utilization

NASA Astrophysics Data System (ADS)

Pracht, Lara E.; Tfaily, Malak M.; Ardissono, Robert J.; Neumann, Rebecca B.

2018-03-01

Bioavailable organic carbon in aquifer recharge waters and sediments can fuel microbial reactions with implications for groundwater quality. A previous incubation experiment showed that sedimentary organic carbon (SOC) mobilized off sandy sediment collected from an arsenic-contaminated and methanogenic aquifer in Bangladesh was bioavailable; it was transformed into methane. We used high-resolution mass spectrometry to molecularly characterize this mobilized SOC, reference its composition against dissolved organic carbon (DOC) in surface recharge water, track compositional changes during incubation, and advance understanding of microbial processing of organic carbon in anaerobic environments. Organic carbon mobilized off aquifer sediment was more diverse, proportionately larger, more aromatic, and more oxidized than DOC in surface recharge. Mobilized SOC was predominately composed of terrestrially derived organic matter and had characteristics signifying that it evaded microbial processing within the aquifer. Approximately 50 % of identified compounds in mobilized SOC and in DOC from surface recharge water contained sulfur. During incubation, after mobilized SOC was converted into methane, new organosulfur compounds with high S-to-C ratios and a high nominal oxidation state of carbon (NOSC) were detected. We reason that these detected compounds formed abiotically following microbial reduction of sulfate to sulfide, which could have occurred during incubation but was not directly measured or that they were microbially synthesized. Most notably, microbes transformed all carbon types during incubation, including those currently considered thermodynamically unviable for microbes to degrade in anaerobic conditions (i.e., those with a low NOSC). In anaerobic environments, energy yields from redox reactions are small and the amount of energy required to remove electrons from highly reduced carbon substrates during oxidation decreases the thermodynamic favorability of degrading compounds with a low NOSC. While all compound types were eventually degraded during incubation, NOSC and compound size controlled the rates of carbon transformation. Large, more thermodynamically favorable compounds (e.g., aromatics with a high NOSC) were targeted first, while small, less thermodynamically favorable compounds (e.g., alkanes and olefinics with a low NOSC) were used last. These results indicate that in anaerobic conditions, microbial communities are capable of degrading and mineralizing all forms of organic matter, converting larger energy-rich compounds into smaller energy-poor compounds. However, in an open system, where fresh carbon is continually supplied, the slower degradation rate of reduced carbon compounds would enable this portion of the organic carbon pool to build up, explaining the apparent persistence of compounds with a low NOSC in anaerobic environments.

Evaluation of the Association between Persistent Organic ...

EPA Pesticide Factsheets

Background: Diabetes is a major threat to public health in the United States and worldwide. Understanding the role of environmental chemicals in the development or progression of diabetes is an emerging issue in environmental health.Objective: We assessed the epidemiologic literature for evidence of associations between persistent organic pollutants (POPs) and type 2 diabetes.Methods: Using a PubMed search and reference lists from relevant studies or review articles, we identified 72 epidemiological studies that investigated associations of persistent organic pollutants (POPs) with diabetes. We evaluated these studies for consistency, strengths and weaknesses of study design (including power and statistical methods), clinical diagnosis, exposure assessment, study population characteristics, and identification of data gaps and areas for future research.Conclusions: Heterogeneity of the studies precluded conducting a meta-analysis, but the overall evidence is sufficient for a positive association of some organochlorine POPs with type 2 diabetes. Collectively, these data are not sufficient to establish causality. Initial data mining revealed that the strongest positive correlation of diabetes with POPs occurred with organochlorine compounds, such as trans-nonachlor, dichlorodiphenyldichloroethylene (DDE), polychlorinated biphenyls (PCBs), and dioxins and dioxin-like chemicals. There is less indication of an association between other nonorganochlorine POPs, such as

Soil Organic Matter (SOM): Molecular Simulations

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

Andersen, Amity

Molecular simulation is a powerful tool used to gain an atomistic, molecular, and nanoscale level understanding of the structure, dynamics, and interactions from adsorption on minerals and assembly in aggregates of soil organic matter (SOM). Given the importance of SOM fate and persistence in soils and the current knowledge gaps, applications of atomistic scale simulations to study the complex compounds in SOM and their interactions in self-assembled aggregates composed of different organic matter compounds and with mineral surfaces of different types common in soils are few and far between. Here, we describe various molecular simulation methods that are currently inmore » use in various areas and applicable to SOM research, followed by a brief survey of specific applications to SOM research and an illustration with our own recent efforts in this area. We conclude with an outlook and the challenges for future research in this area.« less

Intracellular survival of Staphylococcus aureus during persistent infection in the insect Tenebrio molitor.

PubMed

McGonigle, John E; Purves, Joanne; Rolff, Jens

2016-06-01

Survival of bacteria within host cells and tissues presents a challenge to the immune systems of higher organisms. Escape from phagocytic immune cells compounds this issue, as immune cells become potential vehicles for pathogen dissemination. However, the duration of persistence within phagocytes and its contribution to pathogen load has yet to be determined. We investigate the immunological significance of intracellular persistence within the insect model Tenebrio molitor, assessing the extent, duration and location of bacterial recovery during a persistent infection. Relative abundance of Staphylococcus aureus in both intracellular and extracellular fractions was determined over 21 days, and live S. aureus were successfully recovered from both the hemolymph and within phagocytic immune cells across the entire time course. The proportion of bacteria recovered from within phagocytes also increased over time. Our results show that to accurately estimate pathogen load it is vital to account for bacteria persisting within immune cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

SAR202 Genomes from the Dark Ocean Predict Pathways for the Oxidation of Recalcitrant Dissolved Organic Matter.

PubMed

Landry, Zachary; Swan, Brandon K; Herndl, Gerhard J; Stepanauskas, Ramunas; Giovannoni, Stephen J

2017-04-18

Deep-ocean regions beyond the reach of sunlight contain an estimated 615 Pg of dissolved organic matter (DOM), much of which persists for thousands of years. It is thought that bacteria oxidize DOM until it is too dilute or refractory to support microbial activity. We analyzed five single-amplified genomes (SAGs) from the abundant SAR202 clade of dark-ocean bacterioplankton and found they encode multiple families of paralogous enzymes involved in carbon catabolism, including several families of oxidative enzymes that we hypothesize participate in the degradation of cyclic alkanes. The five partial genomes encoded 152 flavin mononucleotide/F420-dependent monooxygenases (FMNOs), many of which are predicted to be type II Baeyer-Villiger monooxygenases (BVMOs) that catalyze oxygen insertion into semilabile alicyclic alkanes. The large number of oxidative enzymes, as well as other families of enzymes that appear to play complementary roles in catabolic pathways, suggests that SAR202 might catalyze final steps in the biological oxidation of relatively recalcitrant organic compounds to refractory compounds that persist. IMPORTANCE Carbon in the ocean is massively sequestered in a complex mixture of biologically refractory molecules that accumulate as the chemical end member of biological oxidation and diagenetic change. However, few details are known about the biochemical machinery of carbon sequestration in the deep ocean. Reconstruction of the metabolism of a deep-ocean microbial clade, SAR202, led to postulation of new biochemical pathways that may be the penultimate stages of DOM oxidation to refractory forms that persist. These pathways are tied to a proliferation of oxidative enzymes. This research illuminates dark-ocean biochemistry that is broadly consequential for reconstructing the global carbon cycle. Copyright © 2017 Landry et al.

Concentration of organic contaminants in fish and their biological effects in a wastewater-dominated urban stream

USGS Publications Warehouse

Lozano, Nuria; Rice, Clifford P.; Pagano, James; Zintek, Larry; Barber, Larry B.; Murphy, Elizabeth W.; Nettesheim, Todd G.; Minarik, Thomas A.; Schoenfuss, Heiko L.

2012-01-01

Data are presented on the concentrations of alkylphenol and alkylphenol ethoxylates (APEs) and persistent organic compounds in largemouth bass collected from a waste-water dominated stream in downtown Chicago. The fish residue concentrations of APEs are compared to concentrations of the APEs in the water that were collected at weekly intervals over two months bracketing the fall (2006) and a spring (2007) fish collection. The concentrations of APEs were significantly higher in the spring-collected fish (5.42 μg/g) versus the fall (0.99 μg/g) tand these differences were shared by differences in the water concentrations (spring — 11.47 versus fall — 3.44 μg/L). The differences in water concentration were negatively correlated with water temperatures observed over the two sampling times. Fish residue concentrations of persistent organic compounds (PCBs, PBDEs, toxaphene, and many legacy pesticides including the DDT family) did not vary from fall to spring. Some of these residue concentrations were comparable to the highest NPE (nonylphenol ethoxylate) homologue concentrations, e.g. NP1EO was 3.5 μg/g in the bass for the spring, the PBDE-congener 47 and p,p′-DDE averaged 1.0 μg/g and 0.5 μg/g, respectively, over both seasons. All the other persistent single-analyte concentrations were lower. Biological endpoints for endocrine effects measured in the same fish showed that there was an apparent positive correlation for physiological effects based on increased vitellogenin levels in males versus concentration of NPEs; however there were no observable histological differences in fall versus spring fish samples.

Occurrence, composition and ecological restoration of organic pollutants in water environment of South Canal, China

NASA Astrophysics Data System (ADS)

Wang, Y. Z.; Lin, C.; Zhou, X. S.; Zhang, Y.; Han, C. G.

2017-08-01

Ecological restoration of polluted river water was carried out in South Canal by adding microbial water purifying agents and biological compound enzymes. The objective of present study was to investigate the ecological restoration effect of organic pollutants by this efficient immobilized microbial technologies, analysis the occurrence and composition of organic pollutants including fifteen persistent organochlorine pesticides (OCPs), seventeen polycyclic aromatic hydrocarbons (PAHs) and eighteen organophosphorus pesticides (OPPs) both in natural water environment and ecological restoration area of South Canal, China. Results showed that the total concentrations of OCPs ranged from 1.11 to 1.78 ng·L-1, PAHs from 52.76 to 60.28 ng·L-1, and OPPs from 6.51 to 17.50 ng·L-1. Microbial water purifying agents and biological compound enzymes essentially had no effects on biological degradation of OCPs and PAHs in the river, but could remove OPPs with degradation rates ranging from 19.6% to 62.8% (35.2% in average). Degradation mechanisms of microbial water purifying agents and biological compound enzymes on OCPs, PAHs and OPPs remained to be further studied. This technology has a certain value in practical ecological restoration of organic pollutants in rivers and lakes.

Persistent aryl hydrocarbon receptor inducers increase with altitude, and estrogen-like disrupters are low in soils of the Alps.

PubMed

Levy, Walkiria; Henkelmann, Bernhard; Bernhöft, Silke; Bovee, Toine; Buegger, Franz; Jakobi, Gert; Kirchner, Manfred; Bassan, Rodolfo; Kräuchi, Norbert; Moche, Wolfgang; Offenthaler, Ivo; Simončič, Primoz; Weiss, Peter; Schramm, Karl-Werner

2011-01-01

Soil samples from remote Alpine areas were analyzed for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans and polychlorinated biphenyls by high-resolution gas chromatography/high-resolution gas spectrometry. Additionally, the EROD micro-assay and a genetically modified yeast estrogen bioassay were carried out to determine persistent aryl hydrocarbon receptors (AhR) and estrogen receptors (ER) agonists, respectively. Regarding the AhR agonists, the toxicity equivalents of analytical and EROD determined values were compared, targeting both altitude of samples and their soil organic content. The ratio between bioassay derived equivalents and analytical determinations suggested no significant contribution of unknown AhR inducers in these sampling sites and some antagonism in soils with relatively high PCB loading. More CYP1A1 expression was induced at the highest sites or about 1400-1500 m a.s.l. along the altitude profiles. Surprisingly, no clear tendencies with the soil organic content were found for dioxin-like compounds. Mean values obtained in the present study were for ER agonists, 2: 0.37±0.12ng 17ß-estradiol EQ g-1 dry soil [corrected] and 6.1 ± 4.2 pg TCDD-EQ g⁻¹ dry soil for AhR agonists. Low bioassay responses with a higher relative amount of ER disrupters than AhR inducers were detected,indicating the higher abundance of estrogen-like than persistent dioxin-like compounds in these forested areas [corrected].

Environmental Fate of Organophosphorus Compounds Related to Chemical Weapons

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

Davisson, M L; Love, A H; Vance, A

2005-02-08

Man-made organophosphorus compounds have been widely distributed throughout our environment as pesticides since their development during and after WWII. Many important studies have documented their relative persistence and toxicity. Development and use of some organophosphorus compounds as nerve agents gave rise to a separate but parallel effort to understand environmental persistence. In this latter case, the experiments have focused mainly on evaporation rates and first-order reaction kinetics. However, because organophosphorus compounds are easily polarized, the ionic content of a surrounding media directly factors into these reaction rates, but limited work in this regard has been done under environmentally relevant conditions.more » Furthermore, limited experiments investigating persistence of these agents on soil has resulted in widely varying degradation rates. Not surprisingly, no studies have investigated affinities of organophosphorus nerve agents to mineral or organic matter typically found in soil. As a result, we initiated laboratory experiments on dilute concentrations of nerve agent O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothiolate (VX) to quantify persistence in simulated environmental aqueous conditions. A quantitative analytical method was developed for VX and its degradation products using High Performance Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (HPLC-ESI-MS). VX hydrolysis rate is known to have a pH-dependency, however, the type of buffer and the relative proportion of different nucleophiles in solution significantly affect the overall rate and mechanism of degradation. For example, dissolved carbonate, a weak nucleophile dominating natural water, yielded pseudo-first order rate constants of {approx} 8 x 10{sup -3}/hr at pH 5 and 2 x 10{sup -2}/hr at pH 11. This small pH-dependent variation departs significantly from widely accepted rates at this pH range (4 x 10{sup -4}/hr to 8 x 10{sup -2}/hr) that were based on chloride and hydroxyl (strong nucleophile) dominated experimental solutions. Because of its overwhelming abundance in solution relative to hydroxyl ion, bicarbonate likely effectively competes in nucleophilic attack on phosphorus. The addition of natural dissolved organic matter at 100 mg/L in pH 7 bicarbonate buffered solution slowed VX hydrolysis rates {approx}2 times relative to controls, suggesting hydrophobic interaction. Adsorption experiments derived isotherms from batch aqueous experiments on montmorillonite clay, iron-oxyhydroxide goethite, and on amorphous silica. VX had moderate affinity for montmorillonite and amorphous silica, and very low affinity toward goethite. The addition of dissolved organic matter into solution enhanced VX adsorption to goethite, consistent with its high affinity for hydrophobic organic matter (log K{sub oc} = 2.52). Diisopropylaminoethylthiol (DESH), a hydrolysis product of VX showed equivalent adsorption to montmorillonite, and poor affinity to goethite and silica. However, hydrolysis products O-Ethylmethylphosphonic acid (EMPA) and methylphosphonic acid (MPA) strongly adsorbed on goethite, but not on montmorillonite or silica, suggesting a ligand-exchange mechanism. VX degraded rapidly when completely dried onto goethite followed by rehydration, consistent with an irreversible chemical adsorption mechanism.« less

Molecular and Microscopic Insights into the Formation of Soil Organic Matter in a Red Pine Rhizosphere

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

Dohnalkova, Alice C.; Tfaily, Malak M.; Smith, A. Peyton

Microbially-derived carbon inputs to soils play an important role in forming soil organic matter (SOM), but detailed knowledge of basic mechanisms of carbon (C) cycling, such as stabilization of organic C compounds originating from rhizodeposition, is scarce. This study aimed to investigate the stability of rhizosphere-produced carbon components in a model laboratory mesocosm of Pinus resinosa grown in a designed mineral soil mix with limited nutrients. We utilized a suite of advanced imaging and molecular techniques to obtain a molecular-level identification of newly-formed SOM compounds, and considered implications regarding their degree of long-term persistence. The microbes in this controlled, nutrient-limitedmore » system, without pre-existing organic matter, produced extracellular polymeric substances that formed associations with nutrient-bearing minerals and contributed to the microbial mineral weathering process. Electron microscopy revealed unique ultrastructural residual signatures of biogenic C compounds, and the increased presence of an amorphous organic phase associated with the mineral phase was evidenced by X-ray diffraction. Here, these findings provide insight into the formation of SOM products in ecosystems, and show that the plant- and microbially-derived material associated with mineral matrices may be important components in current soil carbon models.« less

Molecular and Microscopic Insights into the Formation of Soil Organic Matter in a Red Pine Rhizosphere

DOE PAGES

Dohnalkova, Alice C.; Tfaily, Malak M.; Smith, A. Peyton; ...

2017-08-26

Microbially-derived carbon inputs to soils play an important role in forming soil organic matter (SOM), but detailed knowledge of basic mechanisms of carbon (C) cycling, such as stabilization of organic C compounds originating from rhizodeposition, is scarce. This study aimed to investigate the stability of rhizosphere-produced carbon components in a model laboratory mesocosm of Pinus resinosa grown in a designed mineral soil mix with limited nutrients. We utilized a suite of advanced imaging and molecular techniques to obtain a molecular-level identification of newly-formed SOM compounds, and considered implications regarding their degree of long-term persistence. The microbes in this controlled, nutrient-limitedmore » system, without pre-existing organic matter, produced extracellular polymeric substances that formed associations with nutrient-bearing minerals and contributed to the microbial mineral weathering process. Electron microscopy revealed unique ultrastructural residual signatures of biogenic C compounds, and the increased presence of an amorphous organic phase associated with the mineral phase was evidenced by X-ray diffraction. Here, these findings provide insight into the formation of SOM products in ecosystems, and show that the plant- and microbially-derived material associated with mineral matrices may be important components in current soil carbon models.« less

Evaluation of the persistence of micropollutants through pure-oxygen activated sludge nitrification and denitrification

USGS Publications Warehouse

Levine, A.D.; Meyer, M.T.; Kish, G.

2006-01-01

The persistence of pharmaceuticals, hormones, and household and industrial chemicals through a pure-oxygen activated sludge, nitrification, denitrification wastewater treatment facility was evaluated. Of the 125 micropollutants that were tested in this study, 55 compounds were detected in the untreated wastewater, and 27 compounds were detected in the disinfected effluent. The persistent compounds included surfactants, fire-retardant chemicals, pesticides, fragrance compounds, hormones, and one pharmaceutical. Physical-chemical properties of micropollutants that affected partitioning onto wastewater solids included vapor pressure and octanol-water partition coefficients.

Selective determination of semi-volatile thiophene compounds in water by molecularly imprinted polymer thin films with direct headspace gas chromatography sulfur chemiluminescence detection.

PubMed

Hijazi, Hassan Y; Bottaro, Christina S

2018-02-26

Water-compatible molecularly imprinted polymer (MIP) thin films are coupled with headspace gas chromatography sulfur chemiluminescence detection (HS-GC-SCD) to create a new approach for the determination of trace concentrations of thiophene compounds in water samples. Thiophene compounds are persistent, typically petrogenic, organic pollutants of concern due to their potential for biomagnification and bioaccumulation, mutagenicity, and carcinogenicity in terrestrial and aquatic fauna. Identification and quantitation in water, particularly following oil spills, is a priority. Following adsorption of the thiophenes to the MIPs, the MIP-bound analytes are analyzed directly by HS-GC-SCD, with minimal sample manipulation and virtually no organic solvent. Calibration curves of spiked seawater were linear from 5 μg L -1 to 100 μg L -1 and limits of detection (LOD) were in the range of 0.24-0.82 μg L -1 . Low matrix effects were observed in the analysis of thiophene compounds in seawater making the method suitable for use in fresh and saline waters without modification. Acceptable reproducibility was obtained for analysis of thiophene compounds from spiked seawater samples at RSDs ≤7.0% (n = 3).

Increased Arctic Deposition of Persistent Compounds as a Result of the Montreal Protocol

NASA Astrophysics Data System (ADS)

Young, C.; Pickard, H. M.; De Silva, A. O.; Spencer, C.; Criscitiello, A. S.; Muir, D.; Sharp, M. J.

2017-12-01

Perfluorocarboxylic acids (PFCAs) are among the diverse groups of compounds characterized as persistent organic pollutants. They are toxic, resistant to environmental degradation, and adversely impact human and environmental health. PFCAs with four or fewer carbons, short-chain PFCAs (scPFCAs), are of particular interest because of their increasing levels in the environment, toxicity to plants, and potential for accumulation in some aquatic ecosystems, making them an emerging environmental concern. A minor source of scPFCAs to the Arctic has been shown to be atmospheric transformation of fluoropolymer precursors, followed by deposition. Additional potential sources of scPFCAs to the Arctic are chlorofluorocarbon (CFC)-replacement compounds. Through analysis of an ice core from the Canadian High Arctic, we show that Montreal Protocol-mandated introduction of CFC-replacement compounds for the heat-transfer industry has led to increasing inputs of these scPFCAs to the remote environment. Flux measurements for scPFCAs as a class of contaminants have only been reported in a couple studies to date. Here, we provide the first multi-decadal temporal record of scPFCA deposition, demonstrating a dramatic increase in deposition resulting from emission of CFC-replacements. These results bring to the forefront a need for a holistic approach to environmental risk assessment that considers impacts of replacement substances and degradation products.

Leaching of organic contaminants from storage of reclaimed asphalt pavement.

PubMed

Norin, Malin; Strömvall, A M

2004-03-01

Recycling of asphalt has been promoted by rapid increases in both the use and price of petroleum-based bitumen. Semi-volatile organic compounds in leachates from reclaimed asphalt pavement, measured in field samples and in laboratory column test, were analysed through a GC/MS screen-test methodology. Sixteen PAH (polyaromatic hydrocarbons) were also analysed in leachates from the column study. The highest concentrations of semi-volatile compounds, approximately 400 microg l(-1), were measured in field samples from the scarified stockpile. Naphthalene, butylated hydroxytoluene (BHT) and dibutyl phthalate (DBP) were the most dominant of the identified semi-volatiles. The occurrence of these compounds in urban groundwater, also indicate high emission rates and persistent structures of the compounds, making them potentially hazardous. Car exhausts, rubber tires and the asphalt material itself are all probable emission sources, determined from the organic contaminants released from the stockpiles. The major leaching mechanism indicated was dissolution of organic contaminants from the surface of the asphalt gravels. In the laboratory column test, the release of high-molecular weight and more toxic PAH was higher in the leachates after two years than at the commencement of storage. The concentrations of semi-volatiles in leachates, were also several times lower than those from the field stockpile. These results demonstrate the need to follow up laboratory column test with real field measurements.

Atmospheric Concentrations of Persistent Organic Pollutants in the Southern Ocean

NASA Astrophysics Data System (ADS)

Vlahos, P.; Edson, J.; Cifuentes, A.; McGillis, W. R.; Zappa, C.

2008-12-01

Long-range transport of persistent organic pollutant (POPs) is a global concern. Remote regions such as the Southern Ocean are greatly under-sampled though critical components in understanding POPs cycling. Over 20 high-volume air samples were collected in the Southern Ocean aboard the RV Brown during the GASEX III experiment between Mar 05 to April 9 2008. The relatively stationary platform (51S,38W) enabled the collection of a unique atmospheric time series at this open ocean station. Air sampling was also conducted across transects from Punto Arenas, Chile and to Montevideo, Uruguay. Samples were collected using glass sleeves packed with poly-urethane foam plugs and C-18 resin in order to collect target organic pollutants (per-fluorinated compounds, currently and historically used pesticides) in this under-sampled region. Here we present POPs concentrations and trends over the sampled period and compare variations with air parcel back trajectories to establish potential origins of their long-range transport.

Response surface modeling for optimization heterocatalytic Fenton oxidation of persistence organic pollution in high total dissolved solid containing wastewater.

PubMed

Sekaran, G; Karthikeyan, S; Boopathy, R; Maharaja, P; Gupta, V K; Anandan, C

2014-01-01

The rice-husk-based mesoporous activated carbon (MAC) used in this study was precarbonized and activated using phosphoric acid. N2 adsorption/desorption isotherm, X-ray powder diffraction, electron spin resonance, X-ray photoelectron spectroscopy and scanning electron microscopy, transmission electron microscopy, (29)Si-NMR spectroscopy, and diffuse reflectance spectroscopy were used to characterize the MAC. The tannery wastewater carrying high total dissolved solids (TDS) discharged from leather industry lacks biodegradability despite the presence of dissolved protein. This paper demonstrates the application of free electron-rich MAC as heterogeneous catalyst along with Fenton reagent for the oxidation of persistence organic compounds in high TDS wastewater. The heterogeneous Fenton oxidation of the pretreated wastewater at optimum pH (3.5), H2O2 (4 mmol/L), FeSO4[Symbol: see text]7H2O (0.2 mmol/L), and time (4 h) removed chemical oxygen demand, biochemical oxygen demand, total organic carbon and dissolved protein by 86, 91, 83, and 90%, respectively.

Transplacental transfer of persistent organic pollutants in La Plata dolphins (Pontoporia blainvillei; Cetartiodactyla, Pontoporiidae).

PubMed

Barbosa, Ana Paula Moreno; Méndez-Fernandez, Paula; Dias, Patrick Simões; Santos, Marcos César Oliveira; Taniguchi, Satie; Montone, Rosalinda Carmela

2018-08-01

Persistent organic pollutants (POPs) accumulate in the fat tissue of living organisms and are found in relatively high concentrations in animals at the top of the food chain, such as dolphins. The ability of these compounds to interact with the endocrine system of marine mammals constitutes a risk for the reproduction and conservation of species. The La Plata dolphin, Pontoporia blainvillei, is exclusive to the southwestern Atlantic Ocean and is classified on the IUCN red list as a vulnerable species. Blubber, liver, kidney and muscle samples from four P. blainvillei mother-fetus pairs were analyzed to evaluate the transfer of POPs to fetal tissues through the placenta. The presence of POPs in fetal tissues indicates the maternal transfer of compounds. In the pregnant females, blubber was the tissue with POP highest concentration, followed by the liver, kidneys and muscles. In the fetuses, POP accumulation mainly occurred in the blubber followed by the muscles, liver and kidneys. Polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDTs) were found in all tissues analyzed and had the highest concentrations among all compounds. The main PCB congeners in the fetal samples had five to seven chlorine atoms. The only polybrominated diphenyl ether (PBDE) in the fetal samples was 47 and was found only in blubber. The main DDT metabolite in the fetuses was p,p'-DDE. POP transfer via the placenta occurs in the first months of gestation and increases with fetal development, according to fetus/mother (F/M) ratio: HCB>DDT>PCB>PBDE>Mirex, which may follow the order of the octanol/water partition coefficient (K ow ) values. Copyright © 2018 Elsevier B.V. All rights reserved.

Examining the association of DDX compounds to sedimentary organic matter

NASA Astrophysics Data System (ADS)

Weathers, N.; Rowlett, K.; Geng, Z.; Morrison, A.; White, H. K.

2016-02-01

The association of hydrophobic organic contaminants (HOCs) with sedimentary organic matter (OM) influences their mobility and bioavailability in the environment. Determining whether these associations result from mechanisms such as sorption, chemical binding or encapsulation is critical for predicting their long-term fate. The pesticide DDT (dichlorodiphenyltrichloroethane) has been previously observed to form bound residues with sedimentary OM although the mechanisms of this association are yet to be fully explored. DDT, which was sprayed ubiquitously in the 1950s and early 1960s, can still be found in the environment today along with its three major metabolites, DDE, DDD and DDMU (collectively known as DDX compounds), and therefore presents a unique opportunity to further explore its long-term associations with OM. To this end, a sediment core from a salt marsh in Dover, Delaware known to contain DDX compounds was collected. A maximum concentration of DDX compounds was found at sediment depths corresponding to the time of the widespread usage of DDT. An initial solvent extraction with toluene provided data on the loosely associated DDX fraction followed by subsequent treatments with sulfuric acid and saponification to release DDX that was encapsulated or bound to the sedimentary matrix. Determining the physical disposition of DDX compounds that persist in sediments for several decades is integral to determining the extent to which they are mobile, bioavailable or sequestered in the marsh.

Persistence of pharmaceutical compounds and other organic wastewater contaminants in a conventional drinking-water-treatment plant.

PubMed

Stackelberg, Paul E; Furlong, Edward T; Meyer, Michael T; Zaugg, Steven D; Henderson, Alden K; Reissman, Dori B

2004-08-15

In a study conducted by the US Geological Survey and the Centers for Disease Control and Prevention, 24 water samples were collected at selected locations within a drinking-water-treatment (DWT) facility and from the two streams that serve the facility to evaluate the potential for wastewater-related organic contaminants to survive a conventional treatment process and persist in potable-water supplies. Stream-water samples as well as samples of raw, settled, filtered, and finished water were collected during low-flow conditions, when the discharge of effluent from upstream municipal sewage-treatment plants accounted for 37-67% of flow in stream 1 and 10-20% of flow in stream 2. Each sample was analyzed for 106 organic wastewater-related contaminants (OWCs) that represent a diverse group of extensively used chemicals. Forty OWCs were detected in one or more samples of stream water or raw-water supplies in the treatment plant; 34 were detected in more than 10% of these samples. Several of these compounds also were frequently detected in samples of finished water; these compounds include selected prescription and non-prescription drugs and their metabolites, fragrance compounds, flame retardants and plasticizers, cosmetic compounds, and a solvent. The detection of these compounds suggests that they resist removal through conventional water-treatment processes. Other compounds that also were frequently detected in samples of stream water and raw-water supplies were not detected in samples of finished water; these include selected prescription and non-prescription drugs and their metabolites, disinfectants, detergent metabolites, and plant and animal steroids. The non-detection of these compounds indicates that their concentrations are reduced to levels less than analytical detection limits or that they are transformed to degradates through conventional DWT processes. Concentrations of OWCs detected in finished water generally were low and did not exceed Federal drinking-water standards or lifetime health advisories, although such standards or advisories have not been established for most of these compounds. Also, at least 11 and as many as 17 OWCs were detected in samples of finished water. Drinking-water criteria currently are based on the toxicity of individual compounds and not combinations of compounds. Little is known about potential human-health effects associated with chronic exposure to trace levels of multiple OWCs through routes such as drinking water. The occurrence in drinking-water supplies of many of the OWCs analyzed for during this study is unregulated and most of these compounds have not been routinely monitored for in the Nation's source- or potable-water supplies. This study provides the first documentation that many of these compounds can survive conventional water-treatment processes and occur in potable-water supplies. It thereby provides information that can be used in setting research and regulatory priorities and in designing future monitoring programs. The results of this study also indicate that improvements in water-treatment processes may benefit from consideration of the response of OWCs and other trace organic contaminants to specific physical and chemical treatments.

Persistence of pharmaceutical compounds and other organic wastewater contaminants in a conventional drinking-water-treatment plant

USGS Publications Warehouse

Stackelberg, P.E.; Furlong, E.T.; Meyer, M.T.; Zaugg, S.D.; Henderson, A.K.; Reissman, D.B.

2004-01-01

In a study conducted by the US Geological Survey and the Centers for Disease Control and Prevention, 24 water samples were collected at selected locations within a drinking-water-treatment (DWT) facility and from the two streams that serve the facility to evaluate the potential for wastewater-related organic contaminants to survive a conventional treatment process and persist in potable-water supplies. Stream-water samples as well as samples of raw, settled, filtered, and finished water were collected during low-flow conditions, when the discharge of effluent from upstream municipal sewage-treatment plants accounted for 37-67% of flow in stream 1 and 10-20% of flow in stream 2. Each sample was analyzed for 106 organic wastewater-related contaminants (OWCs) that represent a diverse group of extensively used chemicals. Forty OWCs were detected in one or more samples of stream water or raw-water supplies in the treatment plant; 34 were detected in more than 10% of these samples. Several of these compounds also were frequently detected in samples of finished water; these compounds include selected prescription and non-prescription drugs and their metabolites, fragrance compounds, flame retardants and plasticizers, cosmetic compounds, and a solvent. The detection of these compounds suggests that they resist removal through conventional water-treatment processes. Other compounds that also were frequently detected in samples of stream water and raw-water supplies were not detected in samples of finished water; these include selected prescription and non-prescription drugs and their metabolites, disinfectants, detergent metabolites, and plant and animal steroids. The non-detection of these compounds indicates that their concentrations are reduced to levels less than analytical detection limits or that they are transformed to degradates through conventional DWT processes. Concentrations of OWCs detected in finished water generally were low and did not exceed Federal drinking-water standards or lifetime health advisories, although such standards or advisories have not been established for most of these compounds. Also, at least 11 and as many as 17 OWCs were detected in samples of finished water. Drinking-water criteria currently are based on the toxicity of individual compounds and not combinations of compounds. Little is known about potential human-health effects associated with chronic exposure to trace levels of multiple OWCs through routes such as drinking water. The occurrence in drinking-water supplies of many of the OWCs analyzed for during this study is unregulated and most of these compounds have not been routinely monitored for in the Nation's source- or potable-water supplies. This study provides the first documentation that many of these compounds can survive conventional water-treatment processes and occur in potable-water supplies. It thereby provides information that can be used in setting research and regulatory priorities and in designing future monitoring programs. The results of this study also indicate that improvements in water-treatment processes may benefit from consideration of the response of OWCs and other trace organic contaminants to specific physical and chemical treatments. ?? 2004 Elsevier B.V. All rights reserved.

Bacterial Degradation of Aromatic Compounds

PubMed Central

Seo, Jong-Su; Keum, Young-Soo; Li, Qing X.

2009-01-01

Aromatic compounds are among the most prevalent and persistent pollutants in the environment. Petroleum-contaminated soil and sediment commonly contain a mixture of polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatics. Aromatics derived from industrial activities often have functional groups such as alkyls, halogens and nitro groups. Biodegradation is a major mechanism of removal of organic pollutants from a contaminated site. This review focuses on bacterial degradation pathways of selected aromatic compounds. Catabolic pathways of naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene are described in detail. Bacterial catabolism of the heterocycles dibenzofuran, carbazole, dibenzothiophene, and dibenzodioxin is discussed. Bacterial catabolism of alkylated PAHs is summarized, followed by a brief discussion of proteomics and metabolomics as powerful tools for elucidation of biodegradation mechanisms. PMID:19440284

Persistent organic pollutants in the Atlantic and southern oceans and oceanic atmosphere.

PubMed

Luek, Jenna L; Dickhut, Rebecca M; Cochran, Michele A; Falconer, Renee L; Kylin, Henrik

2017-04-01

Persistent organic pollutants (POPs) continue to cycle through the atmosphere and hydrosphere despite banned or severely restricted usages. Global scale analyses of POPs are challenging, but knowledge of the current distribution of these compounds is needed to understand the movement and long-term consequences of their global use. In the current study, air and seawater samples were collected Oct. 2007-Jan. 2008 aboard the Icebreaker Oden en route from Göteborg, Sweden to McMurdo Station, Antarctica. Both air and surface seawater samples consistently contained α-hexachlorocyclohexane (α-HCH), γ-HCH, hexachlorobenzene (HCB), α-Endosulfan, and polychlorinated biphenyls (PCBs). Sample concentrations for most POPs in air were higher in the northern hemisphere with the exception of HCB, which had high gas phase concentrations in the northern and southern latitudes and low concentrations near the equator. South Atlantic and Southern Ocean seawater had a high ratio of α-HCH to γ-HCH, indicating persisting levels from technical grade sources. The Atlantic and Southern Ocean continue to be net sinks for atmospheric α-, γ-HCH, and Endosulfan despite declining usage. Copyright © 2017 Elsevier B.V. All rights reserved.

Predictive ecotoxicity of MoA 1 of organic chemicals using in silico approaches.

PubMed

de Morais E Silva, Luana; Alves, Mateus Feitosa; Scotti, Luciana; Lopes, Wilton Silva; Scotti, Marcus Tullius

2018-05-30

Persistent organic products are compounds used for various purposes, such as personal care products, surfactants, colorants, industrial additives, food, pesticides and pharmaceuticals. These substances are constantly introduced into the environment and many of these pollutants are difficult to degrade. Toxic compounds classified as MoA 1 (Mode of Action 1) are low toxicity compounds that comprise nonreactive chemicals. In silico methods such as Quantitative Structure-Activity Relationships (QSARs) have been used to develop important models for prediction in several areas of science, as well as aquatic toxicity studies. The aim of the present study was to build a QSAR model-based set of theoretical Volsurf molecular descriptors using the fish acute toxicity values of compounds defined as MoA 1 to identify the molecular properties related to this mechanism. The selected Partial Least Squares (PLS) results based on the values of cross-validation coefficients of determination (Q cv 2 ) show the following values: Q cv 2 = 0.793, coefficient of determination (R 2 ) = 0.823, explained variance in external prediction (Q ext 2 ) = 0.87. From the selected descriptors, not only the hydrophobicity is related to the toxicity as already mentioned in previously published studies but other physicochemical properties combined contribute to the activity of these compounds. The symmetric distribution of the hydrophobic moieties in the structure of the compounds as well as the shape, as branched chains, are important features that are related to the toxicity. This information from the model can be useful in predicting so as to minimize the toxicity of organic compounds. Copyright © 2018. Published by Elsevier Inc.

Application of Focused Ultrasound-Assisted Extraction for the Quantification of Persistent Organic Pollutions in Liver Tissue of Giant Toad (Rhinella marina).

PubMed

Flores-Ramírez, R; Espinosa-Reyes, G; Cilia-López, V G; González-Mille, D J; Rodríguez-Aguilar, M; Díaz de León-Martínez, L; Díaz-Barriga, F

2017-02-01

A simple and rapid focused ultrasound extraction method was developed for the determination of Persistent Organic Pollutants (POPs) in liver tissue obtained of giant toad (Rhinella marina) using a gas chromatography coupled to a mass detector with electron impact ionization. The performed method for POPs, was validated in fortified matrix, showing linearity from the LOQ up to 100 ng/mL; LODs and LOQs for each compound were between 1.7 and 4.8 and 3.5-7.5 ng/mL, respectively. Recovery rates were among 79%-116% for POPs determined. Finally, the method was applied in liver samples of giant toads found in a malarial area in Mexico. The sensitivity of the proposed method was good enough to ensure reliable determination of target analytes at concentration levels commonly found in this kind of samples.

Organochlorine pesticides, their toxic effects on living organisms and their fate in the environment

PubMed Central

Megha, Pankajshan; Sreedev, Puthur

2016-01-01

Organochlorine (OC) pesticides are synthetic pesticides widely used all over the world. They belong to the group of chlorinated hydrocarbon derivatives, which have vast application in the chemical industry and in agriculture. These compounds are known for their high toxicity, slow degradation and bioaccumulation. Even though many of the compounds which belong to OC were banned in developed countries, the use of these agents has been rising. This concerns particularly abuse of these chemicals which is in practice across the continents. Though pesticides have been developed with the concept of target organism toxicity, often non-target species are affected badly by their application. The purpose of this review is to list the major classes of pesticides, to understand organochlorine pesticides based on their activity and persistence, and also to understand their biochemical toxicity. PMID:28652852

Soils impacted by PAHs: Would the stabilized organic matter be a green tool for the immobilization of these noxious compounds?

PubMed

Dores-Silva, Paulo R; Cotta, Jussara A O; Landgraf, Maria D; Rezende, Maria O O

2018-05-04

The objective of this study was to investigate the role of stabilized organic matter (vermicompost) and tropical soils in the sorption of naphthalene, anthracene and benzo[a]pyrene. The results obtained for the three compounds were extrapolated for the priority polycyclic aromatic hydrocarbons (PAHs) pollutants according to Environmental Protection Agency (US EPA). To evaluate the sorption process, high performance liquid chromatography was employed and the data was fitted by Freundlich isotherms. The results suggest that the sorption effect generally increases with the number of benzene rings of the PAHs, and that the persistence of PAHs in the environment is possibly related to the number of benzene rings in the PAH molecule. In addition, the pH of the vermicompost can strongly affect the adsorption process in this matrix.

Potential endocrine disrupting organic chemicals in treated municipal wastewater and river water

USGS Publications Warehouse

Barber, L.B.; Brown, G.K.; Zaugg, S.D.

2000-01-01

Select endocrine disrupting organic chemicals were measured in treated wastewater from Chicago, IL, Minneapolis/St. Paul, MN, Detroit, MI, and Milwaukee, WI, and in the Des Plaines, Illinois, and Minnesota Rivers during the fall of 1997 and the spring of 1998. Emphasis was given to alkylphenolpolyethoxylate (APEO) derived compounds, although 17-??-estradiol, bisphenol A, caffeine, total organic carbon, ethylenediaminetetraacetic acid (EDTA), and other compounds also were measured. Contaminants were isolated by continuous liquid-liquid extraction (CLLE) with methylene chloride and analyzed by gas chromatography/mass spectrometry in full scan and selected ion monitoring modes. The extracts were derivatized to form the methyl esters of alkylphenolethoxycarboxylates (APEC), and EDTA was isolated by evaporation and derivatized to form the tetrapropyl ester. The mass spectra of nonylphenol (NP) and octylphenol (OP) compounds are complex and show variations among the different ethoxylate and carboxylate homologs, reflecting variations in the ethylene oxide chain length. Recoveries for target compounds and surrogate standards ranged from 20-130%, with relative standard deviations of 9.9-53%. Detection limits for the various compounds ranged from 0.06-0.35 ??g/L. Analysis of the wastewater effluents detected a number of compounds including NP, NPEO, OP, OPEO, NPEC, caffeine, and EDTA at concentrations ranging from <1-439 ??g/L, with EDTA and NPEC being most abundant. There was variability in compound distributions and concentrations between the various sewage treatment plants, indicating differences in treatment type and influent composition. Several wastewater-derived compounds were detected in the river samples, with EDTA and NPEC persisting for considerable distance downstream from wastewater discharges, and NP and NPEO being attenuated more rapidly.

Exposure of ruminants to persistent organic pollutants and potential of decontamination.

PubMed

Rychen, Guido; Jurjanz, Stefan; Fournier, Agnès; Toussaint, Hervé; Feidt, Cyril

2014-05-01

Human activities are emitting persistent organic pollutants (POPs) to the environment. These compounds have raised concerns about the risk of transfer through the food chain via animal products. They are characterized by a strong persistence in environmental matrices and a lipophilicity which may lead to their accumulation in fat tissues. In EU Regulations (no. 1881/2006, 1259/2011), maximum acceptable levels for polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs), and dioxin-like or nondioxin-like polychlorinated biphenyls (PCBs) in food of animal origin have been set. Transfer rates from contaminated fodder to milk have been established: for PCBs, the rate of transfer varies from 5 to 90% and for PCDD/Fs from 1 to 40%. The differential transfer of the compounds towards milk is related to the hydrophobicity of the pollutants and to their metabolic susceptibility. According to numerous authors, soil is the major reservoir for POPs, and its involuntary ingestion by farm animals reared outdoors may be the main cause of animal product contamination (meat, milk, or eggs). Recent studies seem to indicate that soil is a real risk matrix in terms of transfer of pollutants to the food chain. A POP crisis management is extremely difficult, since it impacts many farmers located in the contaminated area. The question arising is to know if livestock contaminated by POPs may be decontaminated and further used for their initial purpose. Recent data demonstrate that the decontamination process appear feasible and depends on initial level of contamination or the physiological status of the animals.

Persistent Organic Pollutants in Serum and Several Different Fat Compartments in Humans

DTIC Science & Technology

2011-01-01

vena cava; A: aorta; P: pancreas; K: kidney; L: liver; S: stomach and spleen; C: colon; U: uterus; B: bladder; P: prostate. flame retardants , and...such as dioxins/furans, polychlori- nated biphenyls (PCBs), chlorinated pesticides, brominated Report Documentation Page Form ApprovedOMB No. 0704...perfluorinated compounds. Because of chlorine, bromine , or fluoride groups on the hydrocarbon rings or chains, these substances are resistant to degradation

Ultra-trace determination of Persistent Organic Pollutants in Arctic ice using stir bar sorptive extraction and gas chromatography coupled to mass spectrometry.

PubMed

Lacorte, S; Quintana, J; Tauler, R; Ventura, F; Tovar-Sánchez, A; Duarte, C M

2009-12-04

This study presents the optimization and application of an analytical method based on the use of stir bar sorptive extraction (SBSE) gas chromatography coupled to mass spectrometry (GC-MS) for the ultra-trace analysis of POPs (Persistent Organic Pollutants) in Arctic ice. In a first step, the mass-spectrometry conditions were optimized to quantify 48 compounds (polycyclic aromatic hydrocarbons, brominated diphenyl ethers, chlorinated biphenyls, and organochlorinated pesticides) at the low pg/L level. In a second step, the performance of this analytical method was evaluated to determine POPs in Arctic cores collected during an oceanographic campaign. Using a calibration range from 1 to 1800 pg/L and by adjusting acquisition parameters, limits of detection at the 0.1-99 and 102-891 pg/L for organohalogenated compounds and polycyclic aromatic hydrocarbons, respectively, were obtained by extracting 200 mL of unfiltered ice water. alpha-hexachlorocyclohexane, DDTs, chlorinated biphenyl congeners 28, 101 and 118 and brominated diphenyl ethers congeners 47 and 99 were detected in ice cores at levels between 0.5 to 258 pg/L. We emphasise the advantages and disadvantages of in situ SBSE in comparison with traditional extraction techniques used to analyze POPs in ice.

Layer of organic pine forest soil on top of chlorophenol-contaminated mineral soil enhances contaminant degradation.

PubMed

Sinkkonen, Aki; Kauppi, Sari; Simpanen, Suvi; Rantalainen, Anna-Lea; Strömmer, Rauni; Romantschuk, Martin

2013-03-01

Chlorophenols, like many other synthetic compounds, are persistent problem in industrial areas. These compounds are easily degraded in certain natural environments where the top soil is organic. Some studies suggest that mineral soil contaminated with organic compounds is rapidly remediated if it is mixed with organic soil. We hypothesized that organic soil with a high degradation capacity even on top of the contaminated mineral soil enhances degradation of recalcitrant chlorophenols in the mineral soil below. We first compared chlorophenol degradation in different soils by spiking pristine and pentachlorophenol-contaminated soils with 2,4,6-trichlorophenol in 10-L buckets. In other experiments, we covered contaminated mineral soil with organic pine forest soil. We also monitored in situ degradation on an old sawmill site where mineral soil was either left intact or covered with organic pine forest soil. 2,4,6-Trichlorophenol was rapidly degraded in organic pine forest soil, but the degradation was slower in other soils. If a thin layer of the pine forest humus was added on top of mineral sawmill soil, the original chlorophenol concentrations (high, ca. 70 μg g(-1), or moderate, ca. 20 μg g(-1)) in sawmill soil decreased by >40 % in 24 days. No degradation was noticed if the mineral soil was kept bare or if the covering humus soil layer was sterilized beforehand. Our results suggest that covering mineral soil with an organic soil layer is an efficient way to remediate recalcitrant chlorophenol contamination in mineral soils. The results of the field experiment are promising.

The impact of metallic coagulants on the removal of organic compounds from oil sands process-affected water.

PubMed

Pourrezaei, Parastoo; Drzewicz, Przemysław; Wang, Yingnan; Gamal El-Din, Mohamed; Perez-Estrada, Leonidas A; Martin, Jonathan W; Anderson, Julie; Wiseman, Steve; Liber, Karsten; Giesy, John P

2011-10-01

Coagulation/flocculation (CF) by use of alum and cationic polymer polyDADMAC, was performed as a pretreatment for remediation of oil sands process-affected water (OSPW). Various factors were investigated and the process was optimized to improve efficiency of removal of organic carbon and turbidity. Destabilization of the particles occurred through charge neutralization by adsorption of hydroxide precipitates. Scanning electron microscope images revealed that the resultant flocs were compact. The CF process significantly reduced concentrations of naphthenic acids (NAs) and oxidized NAs by 37 and 86%, respectively, demonstrating the applicability of CF pretreatment to remove a persistent and toxic organic fraction from OSPW. Concentrations of vanadium and barium were decreased by 67-78% and 42-63%, respectively. Analysis of surface functional groups on flocs also confirmed the removal of the NAs compounds. Flocculation with cationic polymer compared to alum, caused toxicity toward the benthic invertebrate, Chironoums dilutus, thus application of the polymer should be limited.

Radiation processing of organics and biological materials exposed to ocean world surface conditions.

NASA Astrophysics Data System (ADS)

Hand, K. P.; Carlson, R. W.

2017-12-01

Assessing the habitability of ocean worlds, such as Europa and Enceladus, motivates a search for endogenous carbon compounds that could be indicative of a habitable, or even inhabited, subsurface liquid water environment. We have examined the role of destruction and synthesis of organic compounds via 10 keV electron bombardment of ices generated under temperature and pressure conditions comparable to Europa and Enceladus. Short-chain organics and ammonia, in combination with water, were exposed to Mrad to Grad doses and observed to evolve to a `lost' carbon fraction (CO and CO2) and a `retained' carbon fraction (consisting of a highly refractory `ocean world tholin' populated by highly radiation resistant carbonyl, aldehyde, and nitrile components). The retained fraction is of key importance as this likely represents the observable fraction for future spacecraft investigations. We also irradiated microbial spores (B. pumilis) to approximately 2 Grad and have found persistence of biomolecule fractions derived from proteins and nucleic acids.

Organic matter preserved in 3-billion-year-old mudstones at Gale crater, Mars

NASA Astrophysics Data System (ADS)

Eigenbrode, Jennifer L.; Summons, Roger E.; Steele, Andrew; Freissinet, Caroline; Millan, Maëva; Navarro-González, Rafael; Sutter, Brad; McAdam, Amy C.; Franz, Heather B.; Glavin, Daniel P.; Archer, Paul D.; Mahaffy, Paul R.; Conrad, Pamela G.; Hurowitz, Joel A.; Grotzinger, John P.; Gupta, Sanjeev; Ming, Doug W.; Sumner, Dawn Y.; Szopa, Cyril; Malespin, Charles; Buch, Arnaud; Coll, Patrice

2018-06-01

Establishing the presence and state of organic matter, including its possible biosignatures, in martian materials has been an elusive quest, despite limited reports of the existence of organic matter on Mars. We report the in situ detection of organic matter preserved in lacustrine mudstones at the base of the ~3.5-billion-year-old Murray formation at Pahrump Hills, Gale crater, by the Sample Analysis at Mars instrument suite onboard the Curiosity rover. Diverse pyrolysis products, including thiophenic, aromatic, and aliphatic compounds released at high temperatures (500° to 820°C), were directly detected by evolved gas analysis. Thiophenes were also observed by gas chromatography–mass spectrometry. Their presence suggests that sulfurization aided organic matter preservation. At least 50 nanomoles of organic carbon persists, probably as macromolecules containing 5% carbon as organic sulfur molecules.

Estimating persistence of brominated and chlorinated organic pollutants in air, water, soil, and sediments with the QSPR-based classification scheme.

PubMed

Puzyn, T; Haranczyk, M; Suzuki, N; Sakurai, T

2011-02-01

We have estimated degradation half-lives of both brominated and chlorinated dibenzo-p-dioxins (PBDDs and PCDDs), furans (PBDFs and PCDFs), biphenyls (PBBs and PCBs), naphthalenes (PBNs and PCNs), diphenyl ethers (PBDEs and PCDEs) as well as selected unsubstituted polycyclic aromatic hydrocarbons (PAHs) in air, surface water, surface soil, and sediments (in total of 1,431 compounds in four compartments). Next, we compared the persistence between chloro- (relatively well-studied) and bromo- (less studied) analogs. The predictions have been performed based on the quantitative structure-property relationship (QSPR) scheme with use of k-nearest neighbors (kNN) classifier and the semi-quantitative system of persistence classes. The classification models utilized principal components derived from the principal component analysis of a set of 24 constitutional and quantum mechanical descriptors as input variables. Accuracies of classification (based on an external validation) were 86, 85, 87, and 75% for air, surface water, surface soil, and sediments, respectively. The persistence of all chlorinated species increased with increasing halogenation degree. In the case of brominated organic pollutants (Br-OPs), the trend was the same for air and sediments. However, we noticed that the opposite trend for persistence in surface water and soil. The results suggest that, due to high photoreactivity of C-Br chemical bonds, photolytic processes occurring in surface water and soil are able to play significant role in transforming and removing Br-OPs from these compartments. This contribution is the first attempt of classifying together Br-OPs and Cl-OPs according to their persistence, in particular, environmental compartments.

Development of a model for predicting reaction rate constants of organic chemicals with ozone at different temperatures.

PubMed

Li, Xuehua; Zhao, Wenxing; Li, Jing; Jiang, Jingqiu; Chen, Jianji; Chen, Jingwen

2013-08-01

To assess the persistence and fate of volatile organic compounds in the troposphere, the rate constants for the reaction with ozone (kO3) are needed. As kO3 values are only available for hundreds of compounds, and experimental determination of kO3 is costly and time-consuming, it is of importance to develop predictive models on kO3. In this study, a total of 379 logkO3 values at different temperatures were used to develop and validate a model for the prediction of kO3, based on quantum chemical descriptors, Dragon descriptors and structural fragments. Molecular descriptors were screened by stepwise multiple linear regression, and the model was constructed by partial least-squares regression. The cross validation coefficient QCUM(2) of the model is 0.836, and the external validation coefficient Qext(2) is 0.811, indicating that the model has high robustness and good predictive performance. The most significant descriptor explaining logkO3 is the BELm2 descriptor with connectivity information weighted atomic masses. kO3 increases with increasing BELm2, and decreases with increasing ionization potential. The applicability domain of the proposed model was visualized by the Williams plot. The developed model can be used to predict kO3 at different temperatures for a wide range of organic chemicals, including alkenes, cycloalkenes, haloalkenes, alkynes, oxygen-containing compounds, nitrogen-containing compounds (except primary amines) and aromatic compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

New approaches to antimicrobial discovery.

PubMed

Lewis, Kim

2017-06-15

The spread of resistant organisms is producing a human health crisis, as we are witnessing the emergence of pathogens resistant to all available antibiotics. An increase in chronic infections presents an additional challenge - these diseases are difficult to treat due to antibiotic-tolerant persister cells. Overmining of soil Actinomycetes ended the golden era of antibiotic discovery in the 60s, and efforts to replace this source by screening synthetic compound libraries was not successful. Bacteria have an efficient permeability barrier, preventing penetration of most synthetic compounds. Empirically establishing rules of penetration for antimicrobials will form the knowledge base to produce libraries tailored to antibiotic discovery, and will revive rational drug design. Two untapped sources of natural products hold the promise of reviving natural product discovery. Most bacterial species, over 99%, are uncultured, and methods to grow these organisms have been developed, and the first promising compounds are in development. Genome sequencing shows that known producers harbor many more operons coding for secondary metabolites than we can account for, providing an additional rich source of antibiotics. Revival of natural product discovery will require high-throughput identification of novel compounds within a large background of known substances. This could be achieved by rapid acquisition of transcription profiles from active extracts that will point to potentially novel compounds. Copyright © 2016 Elsevier Inc. All rights reserved.

Stir bar sorptive extraction-thermal desorption-gas chromatography-mass spectrometry: an effective tool for determining persistent organic pollutants and nonylphenol in coastal waters in compliance with existing Directives.

PubMed

Sánchez-Avila, Juan; Quintana, Jordi; Ventura, Francesc; Tauler, Romà; Duarte, Carlos M; Lacorte, Silvia

2010-01-01

A multi-residual method based on stir bar sorptive extraction coupled with thermal desorption-gas chromatography-mass spectrometry (SBSE-TD-GC-MS) has been developed to measure 49 organic pollutants (organochlorine pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polybrominated diphenyl ethers and nonylphenol) in seawater. Using 100ml of water, the method exhibited good linearity, with recoveries between 86% and 118% and relative standard deviation between 2% and 24% for almost all compounds. The method was applied to determine target contaminants in Catalonian seawater, including coastal areas, ports and desalination plant feed water. Overall individual compound levels oscillated between 0.16 and 597 ng l(-1); PAHs and nonylpenol were the compounds found at the highest concentrations. The method provided LODs between 0.011 and 2.5 ng l(-1), lower than the Environmental Quality Standards (EQS) fixed by Directive 2008/105/EC. In compliance with the directive, this method can be used as a tool to survey target compounds and is aimed at protecting coastal ecosystems from chemical pollution. Copyright 2009 Elsevier Ltd. All rights reserved.

Dynamic behavior of semivolatile organic compounds in indoor air

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

Loy, Michael David Van

1998-12-09

Exposures to a wide range of air pollutants are often dominated by those occurring in buildings because of three factors: 1) most people spend a large fraction of their time indoors, 2) many pollutants have strong indoor sources, and 3) the dilution volume in buildings is generally several orders of magnitude smaller than that of an urban airshed. Semivolatile organic compounds (SVOCS) are emitted by numerous indoor sources, including tobacco combustion, cooking, carpets, paints, resins, and glues, so indoor gasphase concentrations of these compounds are likely to be elevated relative to ambient levels. The rates of uptake and release ofmore » reversibly sorbing SVOCS by indoor materials directly affect both peak concentrations and persistence of the pollutants indoors after source elimination. Thus, accurate predictions of SVOC dynamics in indoor air require an understanding of contaminant sorption on surface materials such as carpet and wallboard. The dynamic behaviors of gas-phase nicotine and phenanthrene were investigated in a 20 ms stainless steel chamber containing carpet and painted wallboard. Each compound was studied independently, first in the empty chamber, then with each sorbent individually, and finally with both sorbents in the chamber.« less

Poly-3-hydroxybutyrate (PHB) production from alkylphenols, mono and poly-aromatic hydrocarbons using Bacillus sp. CYR1: A new strategy for wealth from waste.

PubMed

Venkateswar Reddy, M; Mawatari, Yasuteru; Yajima, Yuka; Seki, Chigusa; Hoshino, Tamotsu; Chang, Young-Cheol

2015-09-01

In the present study five different types of alkylphenols, each of the two different types of mono and poly-aromatic hydrocarbons were selected for degradation, and conversion into poly-3-hydroxybutyrate (PHB) using the Bacillus sp. CYR1. Strain CYR1 showed growth with various toxic organic compounds. Degradation pattern of all the organic compounds at 100 mg/l concentration with or without addition of tween-80 were analyzed using high pressure liquid chromatography (HPLC). Strain CYR1 showed good removal of compounds in the presence of tween-80 within 3 days, but it took 6 days without addition of tween-80. Strain CYR1 showed highest PHB production with phenol (51 ± 5%), naphthalene (42 ± 4%), 4-chlorophenol (32 ± 3%) and 4-nonylphenol (29 ± 3%). The functional groups, structure, and thermal properties of the produced PHB were analyzed. These results denoted that the strain Bacillus sp. CYR1 can be used for conversion of different toxic compounds persistent in wastewaters into useable biological polyesters. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect-based assessment of persistent organic pollutant and pesticide dumpsite using mammalian CALUX reporter cell lines.

PubMed

Pieterse, B; Rijk, I J C; Simon, E; van Vugt-Lussenburg, B M A; Fokke, B F H; van der Wijk, M; Besselink, H; Weber, R; van der Burg, B

2015-10-01

A combined chemical and biological analysis of samples from a major obsolete pesticide and persistent organic pollutant (POP) dumpsite in Northern Tajikistan was carried out. The chemical analytical screening focused on a range of prioritized compounds and compounds known to be present locally. Since chemical analytics does not allow measurements of hazards in complex mixtures, we tested the use of a novel effect-based approach using a panel of quantitative high-throughput CALUX reporter assays measuring distinct biological effects relevant in hazard assessment. Assays were included for assessing effects related to estrogen, androgen, and progestin signaling, aryl hydrocarbon receptor-mediated signaling, AP1 signaling, genotoxicity, oxidative stress, chemical hypoxia, and ER stress. With this panel of assays, we first quantified the biological activities of the individual chemicals measured in chemical analytics. Next, we calculated the expected sum activity by these chemicals in the samples of the pesticide dump site and compared the results with the measured CALUX bioactivity of the total extracts of these samples. The results showed that particularly endocrine disruption-related effects were common among the samples. This was consistent with the toxicological profiles of the individual chemicals that dominated these samples. However, large discrepancies between chemical and biological analysis were found in a sample from a burn place present in this site, with biological activities that could not be explained by chemical analysis. This is likely to be caused by toxic combustion products or by spills of compounds that were not targeted in the chemical analysis.

A national-scale assessment of micro-organic contaminants in groundwater of England and Wales.

PubMed

Manamsa, Katya; Crane, Emily; Stuart, Marianne; Talbot, John; Lapworth, Dan; Hart, Alwyn

2016-10-15

A large variety of micro-organic (MO) compounds is used in huge quantities for a range of purposes (e.g. manufacturing, food production, healthcare) and is now being frequently detected in the aquatic environment. Interest in the occurrence of MO contaminants in the terrestrial and aquatic environments continues to grow, as well as in their environmental fate and potential toxicity. However, the contamination of groundwater resources by MOs has a limited evidence base compared to other freshwater resources. Of particular concern are newly 'emerging contaminants' such as pharmaceuticals and lifestyle compounds, particularly those with potential endocrine disrupting properties. While groundwater often has a high degree of protection from pollution due to physical, chemical and biological attenuation processes in the subsurface compared to surface aquatic environments, trace concentrations of a large range of compounds are still detected in groundwater and in some cases may persist for decades due to the long residence times of groundwater systems. This study provides the first national-scale assessment of micro-organic compounds in groundwater in England and Wales. A large set of monitoring data was analysed to determine the relative occurrence and detected concentrations of different groups of compounds and to determine relationships with land-use, aquifer type and groundwater vulnerability. MOs detected including emerging compounds such as caffeine, DEET, bisphenol A, anti-microbial agents and pharmaceuticals as well as a range of legacy contaminants including chlorinated solvents and THMs, petroleum hydrocarbons, pesticides and other industrial compounds. There are clear differences in MOs between land-use types, particularly for urban-industrial and natural land-use. Temporal trends of MO occurrence are assessed but establishing long-term trends is not yet possible. Copyright © 2016 British Geological Survey, NERC. Published by Elsevier B.V. All rights reserved.

The origin and evolution of assessment criteria for persistent, bioaccumulative and toxic (PBT) chemicals and persistent organic pollutants (POPs).

PubMed

Matthies, Michael; Solomon, Keith; Vighi, Marco; Gilman, Andy; Tarazona, Jose V

2016-09-14

General public concern over the effects of persistent chemicals began in the early 1960s. Since then, significant scientific advances have increased our understanding of persistent, bioaccumulative, and toxic (PBT) chemicals and the properties and processes that influence their fates in, and adverse effects on, human health and the environment. In addition to the scientific advances, a number of legislations and agreements for national, international, and global identification and control of PBT chemicals have been adopted. However, some of the rationales and thoughts that were relied upon when the first criteria were developed to identify and categorize PBT chemicals and then POPs (persistent organic pollutants) have not been carried forward. Criteria have been based upon available data of neutral hydrophobic substances as reference chemicals, derived under laboratory conditions. They evolved over the last decades due to the diversification of the protection aims under various national regulatory frameworks and international agreements, advances in methods for estimation of physical/chemical properties, and the identification of chemicals which are non-traditional POPs. Criteria are not defined purely by science; they also are subject to the aims of policy. This paper offers a historical perspective on the development of criteria for PBT chemicals and POPs. It also offers suggestions for rationalization of protection goals, describes some emerging procedures for identification of compounds of concern, and proposes information that needs to be considered when applying criteria to screening and/or evaluation of new chemicals.

River bottom sediment from the Vistula as matrix of candidate for a new reference material.

PubMed

Kiełbasa, Anna; Buszewski, Bogusław

2017-08-01

Bottom sediments are very important in aquatic ecosystems. The sediments accumulate heavy metals and compounds belonging to the group of persistent organic pollutants. The accelerated solvent extraction (ASE) was used for extraction of 16 compounds from PAH group from bottom sediment of Vistula. For the matrix of candidate of a new reference material, moisture content, particle size, loss on ignition, pH, and total organic carbon were determined. A gas chromatograph with a selective mass detector (GC/MS) was used for the final analysis. The obtained recoveries were from 86% (SD=6.9) for anthracene to 119% (SD=5.4) for dibenzo(ah)anthracene. For the candidate for a new reference material, homogeneity and analytes content were determined using a validated method. The results are a very important part of the development and certification of a new reference materials. Copyright © 2017 Elsevier Inc. All rights reserved.

Spatial and temporal trends of persistent organic pollutants and mercury in beluga whales (Delphinapterus leucas) from Alaska.

PubMed

Hoguet, Jennifer; Keller, Jennifer M; Reiner, Jessica L; Kucklick, John R; Bryan, Colleen E; Moors, Amanda J; Pugh, Rebecca S; Becker, Paul R

2013-04-01

Remote locations, such as the Arctic, are often sinks for persistent contaminants which can ultimately bioaccumulate in local wildlife. Assessing temporal contaminant trends in the Arctic is important in understanding whether restrictions on legacy persistent organic pollutants (POPs) have led to concentration declines. Beluga whale (Delphinapterus leucas) tissue samples were collected from two subpopulations (Cook Inlet, Alaska and the eastern Chukchi Sea) between 1989 and 2006. Several POPs (polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethane and related compounds (DDTs), chlordanes, hexachlorocyclohexanes (HCHs), chlorobenzenes, mirex, polybrominated diphenyl ethers (PBDEs) and semi-quantitatively hexabromocyclododecanes (HBCDs)) were measured in 70 blubber samples, and total mercury (Hg) was measured in 67 liver samples from a similar set of individuals. Legacy POPs (PCBs, chlordanes, DDTs, and HCHs) were the predominant organic compound classes in both subpopulations, with median concentrations of 2360ng/g lipid for Σ80PCBs and 1890 ng/g lipid for Σ6DDTs. Backward stepwise multiple regressions showed that at least one of the four independent variables (subpopulation, sampling year, sex, and animal length) influenced the POP and Hg concentrations. ΣPCBs, ΣDDTs, Σchlordanes, Σchlorobenzenes, mirex, and Hg were significantly higher in belugas from the eastern Chukchi Sea than from the Cook Inlet (p≤0.0001). In contrast, Σ8PBDE and α-HBCD concentrations were significantly lower in belugas from the eastern Chukchi Sea than from the Cook Inlet (p<0.0001). Significant temporal increases in concentrations of Σ8PBDE and α-HBCD were observed for both subpopulations (p≤0.0003), and temporal declines were seen for ΣHCHs and Σchlorobenzenes in eastern Chukchi Sea belugas only (p≤0.0107). All other POP and Hg concentrations were stable, indicating either a lagging response of the Arctic to source reductions or the maintenance of concentrations by unregulated sources. Sex and length also significantly influenced some concentrations, and these findings are discussed. Published by Elsevier B.V.

Bacterial bio-resources for remediation of hexachlorocyclohexane.

PubMed

Alvarez, Analía; Benimeli, Claudia S; Saez, Juliana M; Fuentes, María S; Cuozzo, Sergio A; Polti, Marta A; Amoroso, María J

2012-11-15

In the last few decades, highly toxic organic compounds like the organochlorine pesticide (OP) hexachlorocyclohexane (HCH) have been released into the environment. All HCH isomers are acutely toxic to mammals. Although nowadays its use is restricted or completely banned in most countries, it continues posing serious environmental and health concerns. Since HCH toxicity is well known, it is imperative to develop methods to remove it from the environment. Bioremediation technologies, which use microorganisms and/or plants to degrade toxic contaminants, have become the focus of interest. Microorganisms play a significant role in the transformation and degradation of xenobiotic compounds. Many Gram-negative bacteria have been reported to have metabolic abilities to attack HCH. For instance, several Sphingomonas strains have been reported to degrade the pesticide. On the other hand, among Gram-positive microorganisms, actinobacteria have a great potential for biodegradation of organic and inorganic toxic compounds. This review compiles and updates the information available on bacterial removal of HCH, particularly by Streptomyces strains, a prolific genus of actinobacteria. A brief account on the persistence and deleterious effects of these pollutant chemical is also given.

Bacterial Bio-Resources for Remediation of Hexachlorocyclohexane

PubMed Central

Alvarez, Analía; Benimeli, Claudia S.; Saez, Juliana M.; Fuentes, María S.; Cuozzo, Sergio A.; Polti, Marta A.; Amoroso, María J.

2012-01-01

In the last few decades, highly toxic organic compounds like the organochlorine pesticide (OP) hexachlorocyclohexane (HCH) have been released into the environment. All HCH isomers are acutely toxic to mammals. Although nowadays its use is restricted or completely banned in most countries, it continues posing serious environmental and health concerns. Since HCH toxicity is well known, it is imperative to develop methods to remove it from the environment. Bioremediation technologies, which use microorganisms and/or plants to degrade toxic contaminants, have become the focus of interest. Microorganisms play a significant role in the transformation and degradation of xenobiotic compounds. Many Gram-negative bacteria have been reported to have metabolic abilities to attack HCH. For instance, several Sphingomonas strains have been reported to degrade the pesticide. On the other hand, among Gram-positive microorganisms, actinobacteria have a great potential for biodegradation of organic and inorganic toxic compounds. This review compiles and updates the information available on bacterial removal of HCH, particularly by Streptomyces strains, a prolific genus of actinobacteria. A brief account on the persistence and deleterious effects of these pollutant chemical is also given. PMID:23203113

Photochemical Degradation of Petroleum-Derived Water-Soluble Organics into the Background Dissolved Organic Carbon Pool

NASA Astrophysics Data System (ADS)

Podgorski, D. C.; Ray, P. Z.; Roland, N. V.; Corilo, Y. E.; Tarr, M. A.; Guillemette, F.; Spencer, R. G.

2016-02-01

Water-soluble organic (WSO) photoproducts produced from Macondo crude oil (MC252) and a heavy fuel oil (HFO), a surrogate for that which was spilled into the San Francisco Bay by the M/V Cosco Busan, were isolated and irradiated with simulated sunlight to examine the photochemical fate of the products in aquatic ecosystems. Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) reveals marked transformations in the elemental composition of WSOs at specific irradiation periods across a time series that correspond with shifts in bulk properties determined with optical measurements. Blue shifts in EEMs spectra correlate with an increase in formulas classified as unsaturated, high oxygen while the polyphenols and unsaturated, low oxygen compounds decrease. The characteristic A and C humic- and fulvic-like FDOM signatures begin to appear in the EEM spectra of WSOs that were irradiated for as little as 8 to 12 hours, the equivalent of 2 to 3 days of natural sunlight. The presence of the A and C signatures correlate to elemental compositions that exhibit a further decrease in the unsaturated, low oxygen and subsequent increase of unsaturated, high oxygen and highly oxygenated aliphatic compounds. Furthermore, van Krevelen plots reveal a shift toward the compositional space associated with carboxyl-rich aromatic moieties (CRAM) as a function of irradiation period and the appearance of the humic- and fulvic-like FDOM signatures in the EEM spectra. Although the photodegraded WSO products show similarities in FDOM and elemental composition to representative natural dissolved organic matter from their respective pools, persistent petroleum signatures that are not photoactive are still detected. Future studies are required to examine the bioavailability of these photodegraded WSO products to determine if they degrade or persist in the environment.

Identification of an Antimicrobial Agent Effective against Methicillin-Resistant Staphylococcus aureus Persisters Using a Fluorescence-Based Screening Strategy

PubMed Central

Kim, Wooseong; Conery, Annie L.; Rajamuthiah, Rajmohan; Fuchs, Beth Burgwyn; Ausubel, Frederick M.; Mylonakis, Eleftherios

2015-01-01

Persisters are a subpopulation of normal bacterial cells that show tolerance to conventional antibiotics. Persister cells are responsible for recalcitrant chronic infections and new antibiotics effective against persisters would be a major development in the treatment of these infections. Using the reporter dye SYTOX Green that only stains cells with permeabilized membranes, we developed a fluorescence-based screening assay in a 384-well format for identifying compounds that can kill methicillin-resistant Staphylococcus aureus (MRSA) persisters. The assay proved robust and suitable for high throughput screening (Z`-factor: >0.7). In screening a library of hits from a previous screen, which identified compounds that had the ability to block killing of the nematode Caenorhabditis by MRSA, we discovered that the low molecular weight compound NH125, a bacterial histidine kinase inhibitor, kills MRSA persisters by causing cell membrane permeabilization, and that 5 μg/mL of the compound can kill all cells to the limit of detection in a 108 CFU/mL culture of MRSA persisters within 3h. Furthermore, NH125 disrupts 50% of established MRSA biofilms at 20 μg/mL and completely eradicates biofilms at 160 μg/mL. Our results suggest that the SYTOX Green screening assay is suitable for large-scale projects to identify small molecules effective against MRSA persisters and should be easily adaptable to a broad range of pathogens that form persisters. Since NH125 has strong bactericidal properties against MRSA persisters and high selectivity to bacteria, we believe NH125 is a good anti-MRSA candidate drug that should be further evaluated. PMID:26039584

Biosynthesis of polybrominated aromatic organic compounds by marine bacteria

PubMed Central

Agarwal, Vinayak; El Gamal, Abrahim A.; Yamanaka, Kazuya; Poth, Dennis; Kersten, Roland D.; Schorn, Michelle; Allen, Eric E.; Moore, Bradley S.

2014-01-01

Polybrominated diphenyl ethers (PBDEs) and polybrominated bipyrroles are natural products that bioaccumulate in the marine food chain. PBDEs have attracted widespread attention due to their persistence in the environment and potential toxicity to humans. However, the natural origins of PBDE biosynthesis are not known. Here we report marine bacteria as producers of PBDEs and establish a genetic and molecular foundation for their production that unifies paradigms for the elaboration of bromophenols and bromopyrroles abundant in marine biota. We provide biochemical evidence of marine brominase enzymes revealing decarboxylative-halogenation enzymology previously unknown among halogenating enzymes. Biosynthetic motifs discovered in our study were used to mine sequence databases to discover unrealized marine bacterial producers of organobromine compounds. PMID:24974229

Representing metabolic pathway information: an object-oriented approach.

PubMed

Ellis, L B; Speedie, S M; McLeish, R

1998-01-01

The University of Minnesota Biocatalysis/Biodegradation Database (UM-BBD) is a website providing information and dynamic links for microbial metabolic pathways, enzyme reactions, and their substrates and products. The Compound, Organism, Reaction and Enzyme (CORE) object-oriented database management system was developed to contain and serve this information. CORE was developed using Java, an object-oriented programming language, and PSE persistent object classes from Object Design, Inc. CORE dynamically generates descriptive web pages for reactions, compounds and enzymes, and reconstructs ad hoc pathway maps starting from any UM-BBD reaction. CORE code is available from the authors upon request. CORE is accessible through the UM-BBD at: http://www. labmed.umn.edu/umbbd/index.html.

Self-assembled monolayers of shape-persistent macrocycles on graphite: interior design and conformational polymorphism.

PubMed

Vollmeyer, Joscha; Eberhagen, Friederike; Höger, Sigurd; Jester, Stefan-S

2014-01-01

Three shape-persistent naphthylene-phenylene-acetylene macrocycles of identical backbone structures and extraannular substitution patterns but different (empty, apolar, polar) nanopore fillings are self-assembled at the solid/liquid interface of highly oriented pyrolytic graphite and 1,2,4-trichlorobenzene. Submolecularly resolved images of the resulting two-dimensional (2D) crystalline monolayer patterns are obtained by in situ scanning tunneling microscopy. A concentration-dependent conformational polymorphism is found, and open and more dense packing motifs are observed. For all three compounds alike lattice parameters are found, therefore the intermolecular macrocycle distances are mainly determined by their size and symmetry. This is an excellent example that the graphite acts as a template for the macrocycle organization independent from their specific interior.

In-situ molecular-level elucidation of organofluorine binding sites in a whole peat soil.

PubMed

Longstaffe, James G; Courtier-Murias, Denis; Soong, Ronald; Simpson, Myrna J; Maas, Werner E; Fey, Michael; Hutchins, Howard; Krishnamurthy, Sridevi; Struppe, Jochem; Alaee, Mehran; Kumar, Rajeev; Monette, Martine; Stronks, Henry J; Simpson, André J

2012-10-02

The chemical nature of xenobiotic binding sites in soils is of vital importance to environmental biogeochemistry. Interactions between xenobiotics and the naturally occurring organic constituents of soils are strongly correlated to environmental persistence, bioaccessibility, and ecotoxicity. Nevertheless, because of the complex structural and chemical heterogeneity of soils, studies of these interactions are most commonly performed indirectly, using correlative methods, fractionation, or chemical modification. Here we identify the organic components of an unmodified peat soil where some organofluorine xenobiotic compounds interact using direct molecular-level methods. Using (19)F→(1)H cross-polarization magic angle spinning (CP-MAS) nuclear magnetic resonance (NMR) spectroscopy, the (19)F nuclei of organofluorine compounds are used to induce observable transverse magnetization in the (1)H nuclei of organic components of the soil with which they interact after sorption. The observed (19)F→(1)H CP-MAS spectra and dynamics are compared to those produced using model soil organic compounds, lignin and albumin. It is found that lignin-like components can account for the interactions observed in this soil for heptafluoronaphthol (HFNap) while protein structures can account for the interactions observed for perfluorooctanoic acid (PFOA). This study employs novel comprehensive multi-phase (CMP) NMR technology that permits the application of solution-, gel-, and solid-state NMR experiments on intact soil samples in their swollen state.

Persistent organic pollutants in Alaskan ringed seal (Phoca hispida) and walrus (Odobenus rosmarus) blubber

USGS Publications Warehouse

Kucklick, John R.; Krahn, Margaret M.; Becker, Paul R.; Porter, Barbara J.; Schantz, Michele M.; York, Geoffrey S.; O'Hara, Todd M.; Wise, Stephen A.

2006-01-01

Since 1987, the Alaska Marine Mammal Tissue Archival Project (AMMTAP) has collected tissues from 18 marine mammal species. Specimens are archived in the National Institute of Standards and Technology's National Biomonitoring Specimen Bank (NIST-NBSB). AMMTAP has collected blubber, liver and/or kidney specimens from a number of ringed seals (Phoca hispida) from the areas near Nome and Barrow, Alaska and walruses (Odobenus rosmarus) from several locations in the Bering Sea. Thirty-three ringed seal and 15 walrus blubber samples from the NIST-NBSB were analyzed for persistent organic pollutants (POPs). The compounds determined included PCBs (28 congeners or congener groups), DDT and related compounds, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordanes, dieldrin, and mirex. POP concentrations in ringed seal blubber were significantly higher in Barrow than in Nome when statistically accounting for the interaction of age and gender; HCB, however, was not statistically different between the two locations. Unlike males, POP concentrations and age were not significantly correlated in females probably as a result of lactational loss. POP concentrations in walrus blubber were lower than in ringed seal blubber for ΣPCBs, chlordanes, and HCHs, but higher for dieldrin and mirex. POP concentrations in ringed seals and walrus from Alaska provide further evidence that the western Arctic tends to have lower or similar POP concentrations compared to the eastern Canadian Arctic.

Tissue distribution and fate of persistent organic pollutants in Indo-Pacific humpback dolphins from the Pearl River Estuary, China.

PubMed

Gui, Duan; Yu, Riqing; He, Xuan; Tu, Qin; Wu, Yuping

2014-09-15

Eleven persistent organic pollutant (POP) compounds including ∑PCBs, ∑DDTs, ∑HCHs, aldrin, mirex, endrin, ∑CHLs, dieldrin, HCB, heptachlor and pentachlorobenzene were measured in the kidney, liver, muscle, melon and other tissues of Sousa chinensis stranded on the western coast of the Pearl River Estuary in China during 2007-2013. For most parameters of POPs measured, melon tissues contained the highest mean concentrations with the exception of aldrin, which was higher in the kidney and liver tissues. The concentrations of PCBs, DDTs, heptachlor and endrin in the melon tissue exhibited significant correlations with body length, whereas PCBs and heptachlor also displayed significant regression with age. Our studies showed hepatic concentrations of ∑DDTs, ∑HCHs and mirex in S. chinensis were generally higher than those found in cetaceans from other geographic locations. The high levels of POP residues in the testis of one male dolphin suggested an increasing risk of infertility in the species. Copyright © 2014 Elsevier Ltd. All rights reserved.

Persistent organic pollutants in red-crowned cranes (Grus japonensis) from Hokkaido, Japan.

PubMed

Kakimoto, Kensaku; Akutsu, Kazuhiko; Nagayoshi, Haruna; Konishi, Yoshimasa; Kajimura, Keiji; Tsukue, Naomi; Yoshino, Tomoo; Matsumoto, Fumio; Nakano, Takeshi; Tang, Ning; Hayakawa, Kazuichi; Toriba, Akira

2018-01-01

The red-crowned crane (Grus japonensis) from eastern Hokkaido is classified as a Special Natural Monument in Japan. In this study, we determined the concentrations of persistent organic pollutants (POPs) in red-crowned crane muscle tissues (n = 47). Polychlorinated biphenyls (PCBs) had the highest median concentration (240ng/g lipid weight), followed by dichlorodiphenyltrichloroethane and its metabolites (DDTs) (150ng/g lipid weight), chlordane-related compounds (CHLs) (36ng/g lipid weight), hexachlorobenzene (HCB) (16ng/g lipid weight), hexachlorocyclohexanes (HCHs) (4.4ng/g lipid weight), polybrominated diphenyl ethers (PBDEs) (1.8ng/g lipid weight), and finally, Mirex (1.5ng/g lipid weight). Additionally, a positive correlation was found among POP concentrations. No sex differences beyond body parameters were observed. Additionally, red-crowned cranes exhibited a high enantiomeric excess of (+)-alpha-HCH, with enantiomer fractions varying from 0.51 to 0.87 (average: 0.69). Copyright © 2017 Elsevier Inc. All rights reserved.

Polyfluoroalkyl compounds in the aquatic environment: a review of their occurrence and fate.

PubMed

Ahrens, Lutz

2011-01-01

The occurrence and fate of polyfluoroalkyl compounds (PFCs) in the aquatic environment has been recognized as one of the emerging issues in environmental chemistry. PFCs comprise a diverse group of chemicals that are widely used as processing additives during fluoropolymer production and as surfactants in consumer applications for over 50 years. PFCs are known to be persistent, bioaccumulative and have possible adverse effects on humans and wildlife. As a result, perfluorooctane sulfonate (PFOS) has been added to the persistent organic pollutants (POPs) list of the Stockholm Convention in May 2009. However, their homologues, neutral precursor compounds and new PFCs classes continue to be produced. In general, several PFCs from different classes have been detected ubiquitously in the aqueous environment while the concentrations usually range between pg and ng per litre for individual compounds. Sources of PFCs into the aqueous environment are both point sources (e.g., wastewater treatment plant effluents) and nonpoint sources (e.g., surface runoff). The detected congener composition in environmental samples depends on their physicochemical characteristics and may provide information to their sources and transport pathways. However, the dominant transport pathways of individual PFCs to remote regions have not been conclusively characterised to date. The objective of this article is to give an overview on existing knowledge of the occurrence, fate and processes of PFCs in the aquatic environment. Finally, this article identifies knowledge gaps, presents conclusions and recommendations for future work.

Antialgal and antilarval activities of bioactive compounds extracted from the marine dinoflagellate Amphidinium carterae

NASA Astrophysics Data System (ADS)

Kong, Xianyu; Han, Xiurong; Gao, Min; Su, Rongguo; Wang, Ke; Li, Xuzhao; Lu, Wei

2016-12-01

With the global ban on the application of organotin-based marine coatings by the International Maritime Organization, the development of environmentally friendly, low-toxic and nontoxic antifouling compounds for marine industries has become an urgent need. Marine microorganisms have been considered as a potential source of natural antifoulants. In this study, the antifouling potential of marine dinoflagellate Amphidinium carterae, the toxic and red-tide microalgae, was investigated. We performed a series of operations to extract the bioactive substances from Amphidinium carterae and tested their antialgal and antilarval activities. The crude extract of Amphidinium carterae showed significant antialgal activity and the EC50 value against Skeletonema costatum was 55.4 μg mL-1. After purification, the isolated bioactive substances (the organic extract C) exhibited much higher antialgal and antilarval activities with EC50 of 12.9 μg mL-1 against Skeletonema costatum and LC50 of 15.1 μg mL-1 against Amphibalanus amphitrite larvae. Subsequently, IR, Q-TOFMS, and GC-MS were utilized for the structural elucidation of the bioactive compounds, and a series of unsaturated and saturated 16- to 22-carbon fatty acids were detected. The data suggested the bioactive compounds isolated from Amphidinium carterae exhibited a significant inhibiting effect against the diatom Skeletonema costatum and Amphibalanus amphitrite larvae, and could be substitutes for persistent, toxic antifouling compounds.

Investigating the potential role of persistent organic pollutants in Hawaiian green sea turtle fibropapillomatosis

USGS Publications Warehouse

Keller, Jennifer M.; Balazs, George H.; Nilsen, Frances; Rice, Marc; Work, Thierry M.; Jensen, Brenda A.

2014-01-01

It has been hypothesized for decades that environmental pollutants may contribute to green sea turtle fibropapillomatosis (FP), possibly through immunosuppression leading to greater susceptibility to the herpesvirus, the putative causative agent of this tumor-forming disease. To address this question, we measured concentrations of 164 persistent organic pollutants (POPs) and halogenated phenols in 53 Hawaiian green turtle (Chelonia mydas) plasma samples archived by the Biological and Environmental Monitoring and Archival of Sea Turtle Tissues (BEMAST) project at the National Institute of Standards and Technology Marine Environmental Specimen Bank. Four groups of turtles were examined: free-ranging turtles from Kiholo Bay (0% FP, Hawaii), Kailua Bay (low FP, 8%, Oahu), and Kapoho Bay (moderate FP, 38%, Hawaii) and severely tumored stranded turtles that required euthanasia (high FP, 100%, Main Hawaiian Islands). Four classes of POPs and seven halogenated phenols were detected in at least one of the turtles, and concentrations were low (often <200 pg/g wet mass). The presence of halogenated phenols in sea turtles is a novel discovery; their concentrations were higher than most man-made POPs, suggesting that the source of most of these compounds was likely natural (produced by the algal turtle diet) rather than metabolites of man-made POPs. None of the compounds measured increased in concentration with increasing prevalence of FP across the four groups of turtles, suggesting that these 164 compounds are not likely primary triggers for the onset of FP. However, the stranded, severely tumored, emaciated turtle group (n = 14) had the highest concentrations of POPs, which might suggest that mobilization of contaminants with lipids into the blood during late-stage weight loss could contribute to the progression of the disease. Taken together, these data suggest that POPs are not a major cofactor in causing the onset of FP.

Investigating the potential role of persistent organic pollutants in Hawaiian green sea turtle fibropapillomatosis.

PubMed

Keller, Jennifer M; Balazs, George H; Nilsen, Frances; Rice, Marc; Work, Thierry M; Jensen, Brenda A

2014-07-15

It has been hypothesized for decades that environmental pollutants may contribute to green sea turtle fibropapillomatosis (FP), possibly through immunosuppression leading to greater susceptibility to the herpesvirus, the putative causative agent of this tumor-forming disease. To address this question, we measured concentrations of 164 persistent organic pollutants (POPs) and halogenated phenols in 53 Hawaiian green turtle (Chelonia mydas) plasma samples archived by the Biological and Environmental Monitoring and Archival of Sea Turtle Tissues (BEMAST) project at the National Institute of Standards and Technology Marine Environmental Specimen Bank. Four groups of turtles were examined: free-ranging turtles from Kiholo Bay (0% FP, Hawaii), Kailua Bay (low FP, 8%, Oahu), and Kapoho Bay (moderate FP, 38%, Hawaii) and severely tumored stranded turtles that required euthanasia (high FP, 100%, Main Hawaiian Islands). Four classes of POPs and seven halogenated phenols were detected in at least one of the turtles, and concentrations were low (often <200 pg/g wet mass). The presence of halogenated phenols in sea turtles is a novel discovery; their concentrations were higher than most man-made POPs, suggesting that the source of most of these compounds was likely natural (produced by the algal turtle diet) rather than metabolites of man-made POPs. None of the compounds measured increased in concentration with increasing prevalence of FP across the four groups of turtles, suggesting that these 164 compounds are not likely primary triggers for the onset of FP. However, the stranded, severely tumored, emaciated turtle group (n=14) had the highest concentrations of POPs, which might suggest that mobilization of contaminants with lipids into the blood during late-stage weight loss could contribute to the progression of the disease. Taken together, these data suggest that POPs are not a major cofactor in causing the onset of FP.

Long-term monitoring of persistent organic pollutants (POPs) at the Norwegian Troll station in Dronning Maud Land, Antarctica

NASA Astrophysics Data System (ADS)

Kallenborn, R.; Breivik, K.; Eckhardt, S.; Lunder, C. R.; Manø, S.; Schlabach, M.; Stohl, A.

2013-03-01

A first long-term monitoring of selected persistent organic pollutants (POPs) in Antarctic air has been conducted at the Norwegian Research station Troll (Dronning Maud Land). As target contaminants 32 PCB congeners, a- and g-hexachlorocyclohexane (HCH), trans- and cis-chlordane, trans- and cis-nonachlor, p,p'- and o,p-DDT, DDD, DDE as well as hexachlorobenzene (HCB) were selected. The monitoring program with weekly samples taken during the period 2007-2010 was coordinated with the parallel program at the Norwegian Arctic monitoring site (Zeppelin mountain, Ny-Ålesund, Svalbard) in terms of priority compounds, sampling schedule as well as analytical methods. The POP concentration levels found in Antarctica were considerably lower than Arctic atmospheric background concentrations. Similar as observed for Arctic samples, HCB is the predominant POP compound with levels of around 22 pg m-3 throughout the entire monitoring period. In general, the following concentration distribution was found for the Troll samples analyzed: HCB > Sum HCH > Sum PCB > Sum DDT > Sum chlordanes. Atmospheric long-range transport was identified as a major contamination source for POPs in Antarctic environments. Several long-range transport events with elevated levels of pesticides and/or compounds with industrial sources were identified based on retroplume calculations with a Lagrangian particle dispersion model (FLEXPART). The POP levels determined in Troll air were compared with 1 concentrations found in earlier measurement campaigns at other Antarctic research stations from the past 18 yr. Except for HCB for which similar concentration distributions were observed in all sampling campaigns, concentrations in the recent Troll samples were lower than in samples collected during the early 1990s. These concentration reductions are obviously a direct consequence of international regulations restricting the usage of POP-like chemicals on a worldwide scale.

Marine-Derived Biocatalysts: Importance, Accessing, and Application in Aromatic Pollutant Bioremediation

PubMed Central

Nikolaivits, Efstratios; Dimarogona, Maria; Fokialakis, Nikolas; Topakas, Evangelos

2017-01-01

The aim of the present review is to highlight the potential use of marine biocatalysts (whole cells or enzymes) as an alternative bioprocess for the degradation of aromatic pollutants. Firstly, information about the characteristics of the still underexplored marine environment and the available scientific tools used to access novel marine-derived biocatalysts is provided. Marine-derived enzymes, such as dioxygenases and dehalogenases, and the involved catalytic mechanisms for the degradation of aromatic and halogenated compounds, are presented, with the purpose of underpinning their potential use in bioremediation. Emphasis is given on persistent organic pollutants (POPs) that are organic compounds with significant impact on health and environment due to their resistance in degradation. POPs bioaccumulate mainly in the fatty tissue of living organisms, therefore current efforts are mostly focused on the restriction of their use and production, since their removal is still unclear. A brief description of the guidelines and criteria that render a pollutant POP is given, as well as their potential biodegradation by marine microorganisms by surveying recent developments in this rather unexplored field. PMID:28265269

Decontamination of soils containing PAHs by electroremediation: a review.

PubMed

Pazos, M; Rosales, E; Alcántara, T; Gómez, J; Sanromán, M A

2010-05-15

During the last years, the anthropogenic sources have contributed to organic compound penetration into the environment. One large group of persistent and toxic contaminants is the hydrophobic organic contaminants. Among them, polycyclic aromatic hydrocarbons (PAHs) have been recognized as a representative group of these pollutants with low solubility. In this paper, it is showed the electroremediation of soil contaminated with PAHs as an alternative, to organic compound removal. This technique, mainly used for heavy metal extraction, applies the electric current to promote the movement of contaminants. Nowadays the application of this technique alone or combined with other techniques as for example Fenton or bioremediation is taking fine results to PAHs removal. Although the PAHs soil decontamination by means of the electric field is in an initial stage, many researchers have demonstrated the treatment effectiveness. This paper describes the foremost principles to carry out the electroremediation of soils contaminated with PAHs, just like the different alternatives to improve the electroremediation of PAHs and also the new methodologies of PAHs removal by using hybrid technologies. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Organic marker compounds in surface soils of crop fields from the San Joaquin Valley fugitive dust characterization study

NASA Astrophysics Data System (ADS)

Rogge, Wolfgang F.; Medeiros, Patricia M.; Simoneit, Bernd R. T.

Fugitive dust from the erosion of arid and fallow land, after harvest and during agricultural activities, can at times be the dominant source of airborne particulate matter. In order to assess the source contributions to a given site, chemical mass balance (CMB) modeling is typically used together with source-specific profiles for organic and inorganic constituents. Yet, the mass balance closure can be achieved only if emission profiles for all major sources are considered. While a higher degree of mass balance closure has been achieved by adding individual organic marker compounds to elements, ions, EC, and organic carbon (OC), major source profiles for fugitive dust are not available. Consequently, neither the exposure of the population living near fugitive dust sources from farm land, nor its chemical composition is known. Surface soils from crop fields are enriched in plant detritus from both above and below ground plant parts; therefore, surface soil dust contains natural organic compounds from the crops and soil microbiota. Here, surface soils derived from fields growing cotton, safflower, tomato, almonds, and grapes have been analyzed for more than 180 organic compounds, including natural lipids, saccharides, pesticides, herbicides, and polycyclic aromatic hydrocarbon (PAH). The major result of this study is that selective biogenically derived organic compounds are suitable markers of fugitive dust from major agricultural crop fields in the San Joaquin Valley. Aliphatic homologs exhibit the typical biogenic signatures of epicuticular plant waxes and are therefore indicative of fugitive dust emissions and mechanical abrasion of wax protrusions from leaf surfaces. Saccharides, among which α- and β-glucose, sucrose, and mycose show the highest concentrations in surface soils, have been proposed to be generic markers for fugitive dust from cultivated land. Similarly, steroids are strongly indicative of fugitive dust. Yet, triterpenoids reveal the most pronounced distribution differences for all types of cultivated soils examined here and are by themselves powerful markers for fugitive dust that allow differentiation between the types of crops cultivated. PAHs are also found in some surface soils, as well as persistent pesticides, e.g., DDE, Fosfall, and others.

A broad cocktail of environmental pollutants found in eggs of three seabird species from remote colonies in Norway.

PubMed

Huber, Sandra; Warner, Nicholas A; Nygård, Torgeir; Remberger, Mikael; Harju, Mikael; Uggerud, Hilde T; Kaj, Lennart; Hanssen, Linda

2015-06-01

Eggs of 3 seabird species, common eider (Somateria mollisima), European shag (Phalacrocorax aristotelis aristotelis), and European herring gull (Larus argentatus), were surveyed for a broad range of legacy and emerging pollutants to assess chemical mixture exposure profiles of seabirds from the Norwegian marine environment. In total, 201 chemical substances were targeted for analysis ranging from metals, organotin compounds, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and associated metabolites, chlorinated paraffins, chlorinated and nonchlorinated organic pesticides, per- and polyfluoroalkyl substances (PFAS), dechlorane plus, octachlorostyrene, brominated flame retardants (BFRs), organophosphorous compounds, brominated and alkyl phenols, cyclic siloxanes, and phthalates. Of the chemicals targeted, 149 substances were found above the detection limits, with metals dominating the contaminant profile and comprising 60% of the total contaminant load. Polychlorinated biphenyls, pesticides, organophosphorous compounds, and PFAS were the dominant contaminant classes of organic pollutants found within the seabird species, with the highest loads occurring in herring gulls, followed by shag, and common eider. New generation pollutants (e.g., PFAS, organophosphorous compounds, and alkylphenols) were detected at similar or higher concentrations than the legacy persistent organic pollutants (POPs). Time trends of reported concentrations of legacy POPs appear to have decreased in recent decades from the Norwegian coastal environment. Concentrations of detected pollutants do not appear to have a negative effect on seabird population development within the sampling area. Additional stress caused by pollutants, however, may affect seabird health more at the individual level. © 2015 SETAC.

Intra- and inter-species differences in persistent organic contaminants in the blubber of blue whales and humpback whales from the Gulf of St. Lawrence, Canada.

PubMed

Metcalfe, Chris; Koenig, Brenda; Metcalfe, Tracy; Paterson, Gordon; Sears, Richard

2004-05-01

Biopsy samples of blubber from adult male and female blue whales, and from female and young-of-the-year humpback whales were collected during the summers of 1992-1999 in the Gulf of St. Lawrence, Canada. In blue whales, concentrations of 25 PCB congeners, DDT and metabolites and several other organochlorine compounds were present at higher concentrations in the blubber of males relative to females; reflecting maternal transfer of these persistent contaminants from females into young. Sex-related differences in concentrations were not observed with less persistent contaminants, such as HCHs. In humpback whale samples, there were no significant differences in the concentrations of PCBs and organochlorine compounds in the blubber of females and calves. These data indicate that calves quickly bioaccumulate contaminants by transplacental and lactational routes to concentrations that are in equilibrium with females. In comparisons between contaminant concentrations and patterns in the blubber of female blue and humpback whales, there were no significant differences in concentrations, but the proportions of some PCB congeners, HCH isomers, and DDT and its metabolites were different in the two baleen whale species. These may reflect differences in the diet of the two species, since fish comprise a large part of the diet of humpback whales and blue whales feed exclusively on euphausiid crustaceans (i.e. krill).

Review on fate and mechanism of removal of pharmaceutical pollutants from wastewater using biological approach.

PubMed

Tiwari, Bhagyashree; Sellamuthu, Balasubramanian; Ouarda, Yassine; Drogui, Patrick; Tyagi, Rajeshwar D; Buelna, Gerardo

2017-01-01

Due to research advancement and discoveries in the field of medical science, maintains and provides better human health and safer life, which lead to high demand for production of pharmaceutical compounds with a concomitant increase in population. These pharmaceutical (biologically active) compounds were not fully metabolized by the body and excreted out in wastewater. This micro-pollutant remains unchanged during wastewater treatment plant operation and enters into the receiving environment via the discharge of treated water. Persistence of pharmaceutical compounds in both surface and ground waters becomes a major concern due to their potential eco-toxicity. Pharmaceuticals (emerging micro-pollutants) deteriorate the water quality and impart a toxic effect on living organisms. Therefore, from last two decades, plenty of studies were conducted on the occurrence, impact, and removal of pharmaceutical residues from the environment. This review provides an overview on the fate and removal of pharmaceutical compounds via biological treatment process. Copyright © 2016 Elsevier Ltd. All rights reserved.

Analytical Determination of KDOC-Values of Polycyclic Musk Compounds with HS-SPME and GC/MS/MS

NASA Astrophysics Data System (ADS)

Böhm, L.; Düring, R.-A.

2009-04-01

Polycyclic musk compounds, used as fragrances in cosmetics and detergents, get into rivers via domestic wastewater and sewage treatment plants and with sewage sludge as fertilizer into soils. Because of their persistence and lipophilic character they accumulate in biota, so they are pollutants with environmental relevance. The coefficient KDOC is used to quantify the distribution of substances between aqueous phase and dissolved organic matter (DOM) which is quantified by the determination of dissolved organic carbon (DOC). DOM is of specific relevance for the transport and fate of persistent and lipophilic compounds in the environment. The affinity to DOM increases, the more lipophilic a substance is. So the environmental mobility is enhanced with increasing binding on DOM. For that reason, measured KDOC-values are important to predict the fate and behaviour of chemicals in the environment and should be used for environmental fate modelling purposes. LITZ ET AL. (2007) state that, to carry out a risk-assessment for polycyclic musk compounds, further research on their sorption-behaviour is necessary. For the determination of KDOC-values, different concentrations of humic acid were spiked with a multi-component stock solution. The samples were analysed with headspace solid-phase microextraction in combination with gas chromatography coupled with mass spectrometry (HS-SPME GC/MS/MS). The KDOC-values were calculated according to YABUTA ET AL. (2004). The method was validated with single substance stock solutions and with polycyclic aromatic hydrocarbons (PAHs). The results show that the method is applicable, repeatable and suitable to get KDOC-values for many substances very fast, cheap and solvent-free. With our results KDOC-values for polycyclic musk compounds were determined for the first time. Literature LITZ, N. TH., MüLLER, J. AND BöHMER, W. (2007): Occurrence of Polycyclic Musks in Sewage Sludge and their Behaviour in Soils and Plants. Part 2: Investigation of Polycyclic Musks in Soils and Plants. J Soils Sediments 7: 36-44 YABUTA, H., FUKUSHIMA, M., TANAKA, F., ICHIKAWA, H. AND TATSUMI, K. (2004): Solid-phase Microextraction for the Evaluation of Partition Coefficients of a Chlorinated Dioxin and Hexachlorobenzene into Humic Substances. Anal. Sci. 20: 787-791

Pharmaceuticals and personal care products in the environment: agents of subtle change?

PubMed Central

Daughton, C G; Ternes, T A

1999-01-01

During the last three decades, the impact of chemical pollution has focused almost exclusively on the conventional "priority" pollutants, especially those acutely toxic/carcinogenic pesticides and industrial intermediates displaying persistence in the environment. This spectrum of chemicals, however, is only one piece of the larger puzzle in "holistic" risk assessment. Another diverse group of bioactive chemicals receiving comparatively little attention as potential environmental pollutants includes the pharmaceuticals and active ingredients in personal care products (in this review collectively termed PPCPs), both human and veterinary, including not just prescription drugs and biologics, but also diagnostic agents, "nutraceuticals," fragrances, sun-screen agents, and numerous others. These compounds and their bioactive metabolites can be continually introduced to the aquatic environment as complex mixtures via a number of routes but primarily by both untreated and treated sewage. Aquatic pollution is particularly troublesome because aquatic organisms are captive to continual life-cycle, multigenerational exposure. The possibility for continual but undetectable or unnoticed effects on aquatic organisms is particularly worrisome because effects could accumulate so slowly that major change goes undetected until the cumulative level of these effects finally cascades to irreversible change--change that would otherwise be attributed to natural adaptation or ecologic succession. As opposed to the conventional, persistent priority pollutants, PPCPs need not be persistent if they are continually introduced to surface waters, even at low parts-per-trillion/parts-per-billion concentrations (ng-microg/L). Even though some PPCPs are extremely persistent and introduced to the environment in very high quantities and perhaps have already gained ubiquity worldwide, others could act as if they were persistent, simply because their continual infusion into the aquatic environment serves to sustain perpetual life-cycle exposures for aquatic organisms. This review attempts to synthesize the literature on environmental origin, distribution/occurrence, and effects and to catalyze a more focused discussion in the environmental science community. PMID:10592150

Solid waste containing persistent organic pollutants in Serbia: From precautionary measures to the final treatment (case study).

PubMed

Stevanovic-Carapina, Hristina; Milic, Jelena; Curcic, Marijana; Randjelovic, Jasminka; Krinulovic, Katarina; Jovovic, Aleksandar; Brnjas, Zvonko

2016-07-01

Sustainable solid waste management needs more dedicated attention in respect of environmental and human health protection. Solid waste containing persistent organic pollutants is of special concern, since persistent organic pollutants are persistent, toxic and of high risk to human health and the environment. The objective of this investigation was to identify critical points in the Serbian system of solid waste and persistent organic pollutants management, to assure the life cycle management of persistent organic pollutants and products containing these chemicals, including prevention and final destruction. Data were collected from the Serbian competent authorities, and led us to identify preventive actions for solid waste management that should reduce or minimise release of persistent organic pollutants into the environment, and to propose actions necessary for persistent organic pollutants solid waste. The adverse impact of persistent organic pollutants is multidimensional. Owing to the lack of treatment or disposal plants for hazardous waste in Serbia, the only option at the moment to manage persistent organic pollutants waste is to keep it in temporary storage and when conditions are created (primarily financial), such waste should be exported for destruction in hazardous waste incinerators. Meanwhile, it needs to be assured that any persistent organic pollutants management activity does not negatively impact recycling flows or disturb progress towards a more circular economy in Serbia. © The Author(s) 2016.

Fate of carbamazepine, its metabolites, and lamotrigine in soils irrigated with reclaimed wastewater: Sorption, leaching and plant uptake.

PubMed

Paz, Anat; Tadmor, Galit; Malchi, Tomer; Blotevogel, Jens; Borch, Thomas; Polubesova, Tamara; Chefetz, Benny

2016-10-01

Irrigation with reclaimed wastewater may result in the ubiquitous presence of pharmaceutical compounds (PCs) and their metabolites in the agroecosystem. In this study, we focused on two highly persistent anticonvulsant drugs, lamotrigine and carbamazepine and two of its metabolites (EP-CBZ and DiOH-CBZ), aiming to elucidate their behavior in agricultural ecosystem using batch and lysimeter experiments. Sorption of the studied compounds by soils was found to be governed mainly by the soil organic matter level. Sorption affinity of compounds to soils followed the order lamotrigine > carbamazepine > EP-CBZ > DiOH-CBZ. Sorption was reversible, and no competition between sorbates in bi-solute systems was observed. The results of the lysimeter studies were in accordance with batch experiment findings, demonstrating accumulation of lamotrigine and carbamazepine in top soil layers enriched with organic matter. Detection of carbamazepine and one of its metabolites in rain-fed wheat previously irrigated with reclaimed wastewater, indicates reversibility of their sorption, resulting in their potential leaching and their availability for plant uptake. This study demonstrates the long-term implication of introduction of PCs to the agroecosystem. Copyright © 2016 Elsevier Ltd. All rights reserved.

Detection of decomposition volatile organic compounds in soil following removal of remains from a surface deposition site.

PubMed

Perrault, Katelynn A; Stefanuto, Pierre-Hugues; Stuart, Barbara H; Rai, Tapan; Focant, Jean-François; Forbes, Shari L

2015-09-01

Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains including those deposited on or beneath soil. Soil can act as a sink for VOCs, causing loading of decomposition VOCs in the soil following soft tissue decomposition. The objective of this study was to chemically profile decomposition VOCs from surface decomposition sites after remains were removed from their primary location. Pig carcasses were used as human analogues and were deposited on a soil surface to decompose for 3 months. The remains were then removed from each site and VOCs were collected from the soil for 7 months thereafter and analyzed by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS). Decomposition VOCs diminished within 6 weeks and hydrocarbons were the most persistent compound class. Decomposition VOCs could still be detected in the soil after 7 months using Principal Component Analysis. This study demonstrated that the decomposition VOC profile, while detectable by GC×GC-TOFMS in the soil, was considerably reduced and altered in composition upon removal of remains. Chemical reference data is provided by this study for future investigations of canine alert behavior in scenarios involving scattered or scavenged remains.

Effects of organic wastes on water quality from processing of oil shale from the Green River Formation, Colorado, Utah, and Wyoming

USGS Publications Warehouse

Leenheer, J.A.; Noyes, T.I.

1986-01-01

A series of investigations were conducted during a 6-year research project to determine the nature and effects of organic wastes from processing of Green River Formation oil shale on water quality. Fifty percent of the organic compounds in two retort wastewaters were identified as various aromatic amines, mono- and dicarboxylic acids phenols, amides, alcohols, ketones, nitriles, and hydroxypyridines. Spent shales with carbonaceous coatings were found to have good sorbent properties for organic constituents of retort wastewaters. However, soils sampled adjacent to an in situ retort had only fair sorbent properties for organic constituents or retort wastewater, and application of retort wastewater caused disruption of soil structure characteristics and extracted soil organic matter constituents. Microbiological degradation of organic solutes in retort wastewaters was found to occur preferentially in hydrocarbons and fatty acid groups of compounds. Aromatic amines did not degrade and they inhibited bacterial growth where their concentrations were significant. Ammonia, aromatic amines, and thiocyanate persisted in groundwater contaminated by in situ oil shale retorting, but thiosulfate was quantitatively degraded one year after the burn. Thiocyanate was found to be the best conservative tracer for retort water discharged into groundwater. Natural organic solutes, isolated from groundwater in contact with Green River Formation oil shale and from the White River near Rangely, Colorado, were readily distinguished from organic constituents in retort wastewaters by molecular weight and chemical characteristic differences. (USGS)

Characterization of organic aromatic compounds in soils affected by an uncontrolled tire landfill fire through the use of comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry.

PubMed

Escobar-Arnanz, J; Mekni, S; Blanco, G; Eljarrat, E; Barceló, D; Ramos, L

2018-02-09

Discarded vehicle tires have become an increasing concern worldwide due to the enormous amount of wastes generated and the increasing evidence of health problems associated to their disposal and accidental combustion. Previous studies conducted involving either simulated or open uncontrolled tire fires have identified aromatics belonging to two main classes, volatile organic compounds and polycyclic aromatic compounds (PAHs), as the most relevant chemicals generated in these burning processes. As a consequence, and due to their recognized toxicity, most studies reported up to now have mainly focused on these two categories of compounds being information concerning the possible occurrence of other aromatic classes rather limited. In this study, the enhanced separation power and structural confirmation capabilities provided by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-ToF MS) has been used, for the first time, for the non-targeted analysis of soils impacted by a tire fire and an ash collected at the scene of the fire. In total, 118 volatile and semi-volatile aromatic compounds have been differentiated. Among them, 104 compounds have been either positively or tentatively identified. PAHs with 3-5 rings and their alkyl-derivatives were the most numerous and relevant classes in the investigated samples. A significant number of sulfur, oxygen- and nitrogen-containing PAHs were also detected in the samples. The application of a script function to the raw GC×GC-ToF MS data allowed the fast filtering and automatic recognition of compounds containing halogens in their structure. This part of the study evidenced that only a limited number of regulated persistent organic pollutants were present in the investigated samples. However, it also revealed the presence of emerging organophosphorous flame retardants, whose levels in tire fire impacted soils are reported for the first time. Copyright © 2017 Elsevier B.V. All rights reserved.

Persistence of pharmaceuticals and other organic compounds in chlorinated drinking water as a function of time

USGS Publications Warehouse

Gibs, J.; Stackelberg, P.E.; Furlong, E.T.; Meyer, M.; Zaugg, S.D.; Lippincott, R.L.

2007-01-01

Ninety eight pharmaceuticals and other organic compounds (POOCs) that were amended to samples of chlorinated drinking-water were extracted and analyzed 1, 3, 6, 8, and 10 days after amendment to determine whether the total chlorine residual reacted with the amended POOCs in drinking water in a time frame similar to the residence time of drinking water in a water distribution system. Results indicated that if all 98 were present in the finished drinking water from a drinking-water treatment plant using free chlorine at 1.2??mg/L as the distribution system disinfectant residual, 52 POOCs would be present in the drinking water after 10??days at approximately the same concentration as in the newly finished drinking water. Concentrations of 16 POOCs would be reduced by 32% to 92%, and 22 POOCs would react completely with residual chlorine within 24??h. Thus, the presence of free chlorine residual is an effective means for transforming some POOCs during distribution. ?? 2006 Elsevier B.V. All rights reserved.

The investigation of atmospheric deposition distribution of organochlorine pesticides (OCPs) in Turkey

NASA Astrophysics Data System (ADS)

Cindoruk, S. Sıddık; Tasdemir, Yücel

2014-04-01

Atmospheric deposition is a significant pollution source leading to contamination of remote and clean sites, surface waters and soils. Since persistent organic pollutants (POPs) stay in atmosphere without any degradation, they can be transported and deposited to clean surfaces. Organochlorine pesticides are an important group of POPs which have toxic and harmful effects to living organisms and environment. Therefore, atmospheric deposition levels and characteristics are of importance to determine the pollution quantity of water and soil surfaces in terms of POPs. This study reports the distribution quantities of atmospheric deposition including bulk, dry, wet and air-water exchange of particle and gas phase OCPs as a result of 1-year sampling campaign. Atmospheric deposition distribution showed that the main mechanism for OCPs deposition is wet processes with percentage of 69 of total deposition. OCP compounds' deposition varied according to atmospheric concentration and deposition mechanism. HCH compounds were dominant pesticide species for all deposition mechanisms. HCH deposition constituted the 65% of Σ10OCPs.

Persistence of pharmaceuticals and other organic compounds in chlorinated drinking water as a function of time.

PubMed

Gibs, Jacob; Stackelberg, Paul E; Furlong, Edward T; Meyer, Michael; Zaugg, Steven D; Lippincott, Robert Lee

2007-02-01

Ninety eight pharmaceuticals and other organic compounds (POOCs) that were amended to samples of chlorinated drinking-water were extracted and analyzed 1, 3, 6, 8, and 10 days after amendment to determine whether the total chlorine residual reacted with the amended POOCs in drinking water in a time frame similar to the residence time of drinking water in a water distribution system. Results indicated that if all 98 were present in the finished drinking water from a drinking-water treatment plant using free chlorine at 1.2 mg/L as the distribution system disinfectant residual, 52 POOCs would be present in the drinking water after 10 days at approximately the same concentration as in the newly finished drinking water. Concentrations of 16 POOCs would be reduced by 32% to 92%, and 22 POOCs would react completely with residual chlorine within 24 h. Thus, the presence of free chlorine residual is an effective means for transforming some POOCs during distribution.

Multifaceted processes controlling the distribution of hazardous compounds in the spontaneous combustion of coal and the effect of these compounds on human health.

PubMed

Oliveira, Marcos L S; da Boit, Kátia; Pacheco, Fernanda; Teixeira, Elba C; Schneider, Ismael L; Crissien, Tito J; Pinto, Diana C; Oyaga, Rafael M; Silva, Luis F O

2018-01-01

Pollution generated by hazardous elements and persistent organic compounds that affect coal fire is a major environmental concern because of its toxic nature, persistence, and potential risk to human health. The coal mining activities are growing in the state of Santa Catarina in Brazil, thus the collateral impacts on the health and economy are yet to be analyzed. In addition, the environment is also enduring the collateral damage as the waste materials directly influence the coal by-products applied in civil constructions. This study was aimed to establish the relationships between the composition, morphology, and structural characteristics of ultrafine particles emitted by coal mine fires. In Brazil, the self-combustions produced by Al-Ca-Fe-Mg-Si coal spheres are rich in chalcophile elements (As, Cd, Cu, Hg, Pb, Sb, Se, Sn, and Zn), lithophile elements (Ce, Hf, In, La, Th, and U), and siderophile elements (Co, Cr, Mo, Fe, Ni, and V). The relationship between nanomineralogy and the production of hazardous elements as analyzed by advanced methods for the geochemical analysis of different materials were also delineated. The information obtained by the mineral substance analysis may provide a better idea for the understanding of coal-fire development and assessing the response of particular coal in different combustion processes. Copyright © 2017 Elsevier Inc. All rights reserved.

Soils as sinks or sources for diffuse pollution of the water cycle

NASA Astrophysics Data System (ADS)

Grathwohl, Peter

2010-05-01

Numerous chemical compounds have been released into the environment by human activities and can nowadays be found everywhere, i.e. in the compartments water, soil, and air, at the poles and in high mountains. Examples for a global distribution of toxic compounds are the persistent organic pollutants (PCB, dioxins, PAH, fluorinated surfactants and flame retardants, etc.: "the Stockholm dirty dozen") but also mercury and other metals. Many of these compounds reached a global distribution via the atmo¬sphere; others have been and are still directly applied to top soils at the large scale by agriculture or are released into groundwater at landfill sites or by discharge of treated or untreated waste waters. Sooner or later such compounds end up in the water cycle - often via an intermediate storage in soils. Pollutants in soils are leached by seepage waters, transferred to ground¬water, and transported to rivers via groundwater flow. Adsorbed compounds may be transported from soils into surface waters by erosion processes and will end up in the sediments. Diffuse pollution of the subsurface environment not only reflects the history of the economic development of the modern society but it is still ongoing - e.g. the number of organic pollutants released into the environment is increasing even though the con¬centrations may decrease compared to the past. Evidence shows that many compounds are persistent in the subsurface environment at large time scales (up to centuries). Thus polluted soils already are or may become a future source for pollution of adjacent compartments such as the atmosphere and groundwater. A profound understanding on how diffuse pollutants are stored and processed in the subsurface environment is crucial to assess their long term fate and transport at large scales. Thus integrated studies e.g. at the catchment scale and models are needed which couple not only the relevant compartments (soil - atmosphere - groundwater/surface waters) but also flow and reactive transport. Field observations must allow long-term monitoring (e.g. in hydrological observatories, TERENO etc.), new cross-compartment monitoring strategies need to be applied, and massive parallel numerical codes for prediction of reactive transport of potential water pollutants at catchment scale have to be developed. This is also a prerequisite to assess the impact of climate change as well as land use change on future surface and groundwater quality.

Persistent organic pollutants as predictors of increased FSH:LH ratio in naturally cycling, reproductive age women.

PubMed

Gallo, Mia V; Ravenscroft, Julia; Carpenter, David O; Schell, Lawrence M; Akwesasne Task Force On The Environment

2018-07-01

Although several recent studies suggest endocrine disrupting compounds, such as polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p', DDE), and hexachlorobenzene (HCB), target different organs and systems in the body, their impact on female reproductive function in humans is not well characterized. We seek to determine the relationship between several known endocrine disrupting compounds and a marker of ovarian responsivity, the FSH:LH ratio (higher ratio indicates less ovarian responsivity). For this analysis, 169 naturally cycling women between 21 and 38 years of age completed interviews and had their blood drawn on day 3 of their menstrual cycle for analyses of toxicants, gonadal sex hormones (E 2 and P 4 ), and gonadotropins (FSH and LH). PCB congeners were classified into five groups based on their environmental persistence, distribution in human tissue, and toxicological action, reflecting the structure, mechanism, and known biological activity of individual PCB congeners. For every unit (ppb) increase in the level of the estrogenic PCB group, there was a 5-fold greater risk of a FSH:LH ratio ≥ 2, controlling for individual differences in age, percent body fat, cycle day 3 estradiol levels, parity, alcohol use and cigarette smoking in the past year (exp[ß] = 5; p = ≤0.01). PCB congeners identified as estrogenic were analyzed individually, and, of the 19 potentially estrogenic congeners, five were significantly, and positively related to an increased FSH:LH ratio. Four of these congeners are non-persistent, easily volatilize in the environment, and are easily metabolized, and hence, are indicative of very recent or current exposure. p,p'-DDE and HCB were not associated with FSH:LH ratio. We find a clinical indicator of ovarian responsivity, FSH:LH ratio, is associated with a specific group of estrogenic PCBs. These congeners may become airborne when they volatilize from dredged PCB-contaminated soil or from indoor PCB-containing window caulk and sealants in older buildings leading to inhalation exposure. PCB exposure, particularly to non-persistent, estrogenic congeners, may pose an unrecognized threat to female fecundity within the general population. Copyright © 2018 Elsevier Inc. All rights reserved.

A new marine sediment certified reference material (CRM) for the determination of persistent organic contaminants: IAEA-459.

PubMed

Tolosa, Imma; Cassi, Roberto; Huertas, David

2018-04-11

A new marine sediment certified reference material (IAEA 459) with very low concentrations (μg kg -1 ) for a variety of persistent organic contaminants (POPs) listed by the Stockholm Convention, as well as other POPs and priority substances (PSs) listed in many environmental monitoring programs was developed by the IAEA. The sediment material was collected from the Ham River estuary in South Korea, and the assigned final values were derived from robust statistics on the results provided by selected laboratories which demonstrated technical and quality competence, following the guidance given in ISO Guide 35. The robust mean of the laboratory means was assigned as certified values, for those compounds where the assigned value was derived from at least five datasets and its relative expanded uncertainty was less than 40% of the assigned value (most of the values ranging from 8 to 20%). All the datasets were derived from at least two different analytical techniques which have allowed the assignment of certified concentrations for 22 polychlorinated biphenyl (PCB) congeners, 6 organochlorinated (OC) pesticides, 5 polybrominated diphenyl ethers (PBDEs), and 18 polycyclic aromatic hydrocarbon (PAHs). Mass fractions of compounds that did not fulfill the criteria of certification are considered information values, which include 29 PAHs, 11 PCBs, 16 OC pesticides, and 5 PBDEs. The extensive characterization and associated uncertainties at concentration levels close to the marine sediment quality guidelines will make CRM 459 a valuable matrix reference material for use in marine environmental monitoring programs.

Carotenoids are the likely precursor of a significant fraction of marine dissolved organic matter

PubMed Central

Arakawa, Neal; Aluwihare, Lihini I.; Simpson, Andre J.; Soong, Ronald; Stephens, Brandon M.; Lane-Coplen, Daniel

2017-01-01

The ocean’s biota sequester atmospheric carbon dioxide (CO2) in part by producing dissolved organic matter (DOM) that persists in the ocean for millennia. This long-term accumulation of carbon may be facilitated by abiotic and biotic production of chemical structures that resist degradation, consequently contributing disproportionately to refractory DOM. Compounds that are selectively preserved in seawater were identified in solid-phase extracted DOM (PPL-DOM) using comprehensive gas chromatography (GC) coupled to mass spectrometry (MS). These molecules contained cyclic head groups that were linked to isoprenoid tails, and their overall structures closely resembled carotenoid degradation products (CDP). The origin of these compounds in PPL-DOM was further confirmed with an in vitro β-carotene photooxidation experiment that generated water-soluble CDP with similar structural characteristics. The molecular-level identification linked at least 10% of PPL-DOM carbon, and thus 4% of total DOM carbon, to CDP. Nuclear magnetic resonance spectra of experimental CDP and environmental PPL-DOM overlapped considerably, which indicated that even a greater proportion of PPL-DOM was likely composed of CDP. The CDP-rich DOM fraction was depleted in radiocarbon (14C age > 1500 years), a finding that supports the possible long-term accumulation of CDP in seawater. By linking a specific class of widespread biochemicals to refractory DOM, this work provides a foundation for future studies that aim to examine how persistent DOM forms in the ocean. PMID:28959723

The quantification of short-chain chlorinated paraffins in sediment samples using comprehensive two-dimensional gas chromatography with μECD detection.

PubMed

Muscalu, Alina M; Morse, Dave; Reiner, Eric J; Górecki, Tadeusz

2017-03-01

The analysis of persistent organic pollutants in environmental samples is a challenge due to the very large number of compounds with varying chemical and physical properties. Chlorinated paraffins (CPs) are complex mixtures of chlorinated n-alkanes with varying chain lengths (C 10 to C 30 ) and degree of chlorination (30 to 70% by weight). Their physical-chemical properties make these compounds persistent in the environment and able to bioaccumulate in living organisms. Comprehensive two-dimensional gas chromatography (GC × GC) coupled with micro-electron capture detection (μECD) was used to separate and quantify short-chain chlorinated paraffins (SCCP) in sediment samples. Distinct ordered bands were observed in the GC × GC chromatograms pointing to group separation. Using the Classification function of the ChromaTOF software, summary tables were generated to determine total area counts to set up multilevel-calibration curves for different technical mixes. Fortified sediment samples were analyzed by GC × GC-μECD with minimal extraction and cleanup. Recoveries ranged from 120 to 130%. To further validate the proposed method for the analysis of SCCPs, the laboratory participated in interlaboratory studies for the analysis of standards and sediment samples. The results showed recoveries between 75 and 95% and z-score values <2, demonstrating that the method is suitable for the analysis of SCCPs in soil/sediment samples. Graphical abstract Quantification of SCCPs by 2D-GC-μECD.

Unintentional production of persistent chlorinated and brominated organic pollutants during iron ore sintering processes.

PubMed

Li, Sumei; Liu, Guorui; Zheng, Minghui; Liu, Wenbin; Li, Jinhui; Wang, Mei; Li, Changliang; Chen, Yuan

2017-06-05

Iron ore sintering (SNT) processes are major sources of unintentionally produced chlorinated persistent organic pollutants (POPs), including polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polychlorinated naphthalenes (PCNs). However, few studies of emissions of brominated POPs, such as polybrominated dibenzo-p-dioxins/dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs), during SNT have been performed. Stack gas and fly ash samples from six typical SNT plants in China were collected and analyzed to determine the concentrations and profiles of PCDD/Fs, PCBs, PCNs, PBDD/Fs, and PBDEs, as well as any correlations among these compounds. The PCDD/F, PCB, PCN, PBDD/F, and PBDE emission factors were 2.47, 0.61, 552, 0.32, and 107μgt -1 , respectively (109, 4.07, 10.4, 4.41 and 0.02ng toxic equivalents t -1 , respectively). PCBs were the most abundant compounds by mass, while PCNs were the next most abundant, contributing 51% and 42% to the total POP concentration, respectively. However, PCDD/Fs were the dominant contributors to the chlorinated and brominated POP toxic equivalent concentrations, contributing 89% to the total toxic equivalent concentration. The PCDD/F and other chlorinated and brominated POP concentrations were positively correlated, indicating that chlorinated and brominated POP emissions could be synergistically decreased using the best available technologies/best environmental practices already developed for PCDD/Fs. Copyright © 2017 Elsevier B.V. All rights reserved.

Persistence and partitioning of eight selected pharmaceuticals in the aquatic environment: laboratory photolysis, biodegradation, and sorption experiments.

PubMed

Yamamoto, Hiroshi; Nakamura, Yudai; Moriguchi, Shigemi; Nakamura, Yuki; Honda, Yuta; Tamura, Ikumi; Hirata, Yoshiko; Hayashi, Akihide; Sekizawa, Jun

2009-02-01

We selected eight pharmaceuticals with relatively high potential ecological risk and high consumption-namely, acetaminophen, atenolol, carbamazepine, ibuprofen, ifenprodil, indomethacin, mefenamic acid, and propranolol-and conducted laboratory experiments to examine the persistence and partitioning of these compounds in the aquatic environment. In the results of batch sunlight photolysis experiments, three out of eight pharmaceuticals-propranolol, indomethacin, and ifenprodil-were relatively easily photodegraded (i.e., half-life<24h), whereas the other five pharmaceuticals were relatively stable against sunlight. The results of batch biodegradation experiments using river water suggested relatively slow biodegradation (i.e., half-life>24h) for all eight pharmaceuticals, but the rate constant was dependent on sampling site and time. Batch sorption experiments were also conducted to determine the sorption coefficients to river sediments and a model soil sample. The determined coefficients (K(d) values) were much higher for three amines (atenolol, ifenprodil, and propranolol) than for neutral compounds or carboxylic acids; the K(d) values of the amines were comparable to those of a four-ring polycyclic aromatic hydrocarbon (PAH) pyrene. The coefficients were also higher for sediment/soil with higher organic content, and the organic carbon-based sorption coefficient (logK(oc)) showed a poor linear correlation with the octanol-water distribution coefficient (logD(ow)) at neutral pH. These results suggest other sorption mechanisms-such as electrochemical affinity, in addition to hydrophobic interaction-play an important role in sorption to sediment/soil at neutral pH.

Organic matter preserved in 3-billion-year-old mudstones at Gale crater, Mars.

PubMed

Eigenbrode, Jennifer L; Summons, Roger E; Steele, Andrew; Freissinet, Caroline; Millan, Maëva; Navarro-González, Rafael; Sutter, Brad; McAdam, Amy C; Franz, Heather B; Glavin, Daniel P; Archer, Paul D; Mahaffy, Paul R; Conrad, Pamela G; Hurowitz, Joel A; Grotzinger, John P; Gupta, Sanjeev; Ming, Doug W; Sumner, Dawn Y; Szopa, Cyril; Malespin, Charles; Buch, Arnaud; Coll, Patrice

2018-06-08

Establishing the presence and state of organic matter, including its possible biosignatures, in martian materials has been an elusive quest, despite limited reports of the existence of organic matter on Mars. We report the in situ detection of organic matter preserved in lacustrine mudstones at the base of the ~3.5-billion-year-old Murray formation at Pahrump Hills, Gale crater, by the Sample Analysis at Mars instrument suite onboard the Curiosity rover. Diverse pyrolysis products, including thiophenic, aromatic, and aliphatic compounds released at high temperatures (500° to 820°C), were directly detected by evolved gas analysis. Thiophenes were also observed by gas chromatography-mass spectrometry. Their presence suggests that sulfurization aided organic matter preservation. At least 50 nanomoles of organic carbon persists, probably as macromolecules containing 5% carbon as organic sulfur molecules. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Distribution of some organochlorine compounds (PCB, CBz, and DDE) in beeswax and honey

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

Jan, J.; Cerne, K.

Organochlorines are ranked among the class of prevalent and environmentally persistent synthetic chemicals. Honey bees, beeswax, and honey could be indicators for monitoring environmental pollution by organochlorines such as polychlorobiphenyls (PCBs) and organochloro pesticides. Scarcely any data were reported on the distribution of organochloro compounds between beeswax and honey. Physicochemical factors such as adsorption, volatilization, lipophilicity (octanol-water partition coefficient) and metabolic stability can influence the level of individual organochlorine compounds in beeswax and honey. During wax and honey formation metabolic attack by different enzymes can degrade pollutants. In the PCB and chlorobenzene (CBz) series, biodegradation decreases and bioconcentration increases withmore » increasing degree of chlorine substitution. Regarding the composition of honey (sugars, water, and some organic material and particles such as pollen, organic acid and essential oils in traces), and of beeswax (esters, hydrocarbons, acids and some natural wax from plants as minor components), it is expected that beeswax is more lipophilic and organochlorines could be more enriched in beeswax. However, the presence of particulate matters (e.g., pollen) in honey can increase the level of nonpolar compounds in honey due to sorption processes. This effect has been demonstrated in a similar system where suspended particles can influence the partition coefficient. In this contribution (i) the partition between beeswax and honey of some organochlorine compounds (PCB and CBz isomers, DDE) and (ii) bioconcentration in beeswax and honey from a feeding experiment by administration to honey bees of feed fortified with these compounds is presented and discussed. 17 refs., 3 figs., 1 tab.« less

Inflammatory Asthma Phenotype Discrimination Using an Electronic Nose Breath Analyzer.

PubMed

Plaza, V; Crespo, A; Giner, J; Merino, J L; Ramos-Barbón, D; Mateus, E F; Torrego, A; Cosio, B G; Agustí, A; Sibila, O

2015-01-01

Patients with persistent asthma have different inflammatory phenotypes. The electronic nose is a new technology capable of distinguishing volatile organic compound (VOC) breath-prints in exhaled breath. The aim of the study was to investigate the capacity of electronic nose breath-print analysis to discriminate between different inflammatory asthma phenotypes (eosinophilic, neutrophilic, paucigranulocytic) determined by induced sputum in patients with persistent asthma. Fifty-two patients with persistent asthma were consecutively included in a cross-sectional proof-of-concept study. Inflammatory asthma phenotypes (eosinophilic, neutrophilic and paucigranulocytic) were recognized by inflammatory cell counts in induced sputum. VOC breath-prints were analyzed using the electronic nose Cyranose 320 and assessed by discriminant analysis on principal component reduction, resulting in cross-validated accuracy values. Receiver operating characteristic (ROC) curves were calculated. VOC breath-prints were different in eosinophilic asthmatics compared with both neutrophilic asthmatics (accuracy 73%; P=.008; area under ROC, 0.92) and paucigranulocytic asthmatics (accuracy 74%; P=.004; area under ROC, 0.79). Likewise, neutrophilic and paucigranulocytic breath-prints were also different (accuracy 89%; P=.001; area under ROC, 0.88). An electronic nose can discriminate inflammatory phenotypes in patients with persistent asthma in a regular clinical setting. ClinicalTrials.gov identifier: NCT02026336.

Necessity for Establishment of Inventories for Persistent Organic Pollutants (POPs) in Landfills and Contaminated Sites for an Evaluation of Mobilisation Risk by Climate Change

NASA Astrophysics Data System (ADS)

Weber, Roland; Watson, Alan; Forter, Martin

2010-05-01

The landfilling of persistent hazardous compounds with a tendency to migrate, such as Hexachlorocyclohexane (HCH), polychlorinated biphenyls (PCBs), Hexachlorobenzene (HCB) or Hexachlorobutadiene (HCBD) is a major pollution challenge. Historic dumping and landfilling in badly engineered and unsuitably located sites has resulted in widespread contamination from the landfilling of HCH, HCB and PCB wastes around former production sites. In the case of PCBs this has been exacerbated by subsequent landfilling of contaminated products (oils, capacitors, sealants and other building residues). In most cases locations and amounts are not or vaguely known but impacts are increasingly discovered by monitoring in the most advanced countries with sophisticated monitoring schemes in place. These reveal that entire river systems are being contaminated by these old dumps and contaminated sites and that expensive remediation work is required for to reduce further contamination. In addition more recently other (halogenated) chemicals exhibiting the characteristics of POPs have emerged including e.g. brominated aromatic compounds (e.g. Polybrominated diphenylethers (PBDEs) and other brominated flame retardants) widely used as flame retardants for electronics; textiles, furniture; upholstery; insulation foam etc.) and fluorinated organic pollutants (e.g. PFOS or PFOA used in carpets, textiles, furniture, paper coating etc.). As products containing these chemicals reach the end of their life these hazardous compounds increasingly ended and end up in the waste stream. In most countries a large proportion of these wastes are disposed to landfills. In developing countries and those with economies in transition almost all this waste is landfilled. Consequently the quantities of POPs in municipal waste landfills have increased the last two decades. Therefore in addition to chemical landfills also municipal landfills increasingly become POPs deposits and sources. Because of their persistence and relative mobility, these compounds will persist in landfills for many decades and probably centuries. Over these extended time frames landfill engineering systems, including basal and capping liners, gas and leachate collection systems will inevitably degrade and loose their abilities to contain contamination. Furthermore consideration must now be given to the impacts of climate change and extreme weather events. This is likely to result in higher temperatures with increased volatalisation of semi-volatile compounds; longer dry periods with drying of surface caps; together with higher intensity rainfall events and increased flooding risks. These effects will impact on the integrity of the containment systems. It is therefore inevitable that more of the deposited POPs will leach into rivers, lakes and the larger environment via escaping leachate, ground or surface water as well as escaping to atmosphere by volatilisation. At the same time our reliance on water resources is likely to increase. In order to evaluate the associated risks for human exposure and biodiversity, inventories of deposited POPs and other PBTs need to be established, their locations comprehensively mapped and linked to future flooding scenarios for prediction of contamination of the precious water resources. This interdisciplinary task will require the cooperation between POPs experts, geotechnical engineers, contaminated site/landfill experts, water management specialists and geoscientists working on climate change and flooding.

Perfluorocarboxylic acid (PFCA) atmospheric formation and transport to the Arctic.

NASA Astrophysics Data System (ADS)

Pike-thackray, C.; Selin, N. E.

2015-12-01

Perfluorocarboxylic acids (PFCAs) are highly persistent and toxic environmental contaminants that have been found in remote locations such as the Arctic, far from emission sources. These persistent organic pollutants are emitted directly to the atmosphere as well as being produced by the degradation of precursor compounds in the atmosphere, but recent trends towards increasing precursor emissions and decreasing direct emissions raise the importance of production in the atmosphere. Our work aims to improve understanding of the atmospheric degradation of fluorotelomer precursor compounds to form the long-chain PFCAs PFOA (C8) and PFNA (C9).Using the atmospheric chemical transport model GEOS-Chem, which uses assimilated meteorology to simulate the atmospheric transport of trace gas species, we investigate the interaction of the atmospheric formation of PFCAs and the atmospheric transport of their precursor species. Our simulations are a first application of the GEOS-Chem framework to PFCA chemistry. We highlight the importance of the spatial and temporal variability of background atmospheric chemical conditions experienced during transport. We find that yields and formation times of PFOA and PFNA respond differently and strongly to the photochemical conditions of the atmosphere, such as the abundance of NO, HO2, and other photochemical species.

Fate of polar organic trace compounds infiltrating into an alluvial aquifer from an urban lowland river

NASA Astrophysics Data System (ADS)

Schaper, J. L.; Popp, A. L.; Meinikmann, K.; Shanafield, M.; Banks, E.; Putschew, A.; Lewandowski, J.; Nuetzmann, G.

2016-12-01

High loads of polar organic trace compounds (TrOCs) are frequently detected in urban surface waters threatening both, ecosystem functioning and local drinking water supply. Here we investigate the fate and turnover rate of 17 TrOCs infiltrating from the urban river Erpe into the adjacent alluvial aquifer. River Erpe is a lowland stream in Berlin, Germany that receives up to 80 % of its discharge from a municipal wastewater treatment plant (WWTP) thus containing TrOCs in the µg/L range. To this end, a horizontal piezometer transect extending into the alluvial plane as well as a vertical piezometer nest in the riverbed were installed and sampled in June and July 2016. Within the horizontal transect, redox condition remained aerobic resulting in attenuation rates of up to 25 % for benzotriazol, Carbamazepine, metoprolol and 4 - formylaminoantipyrin. Concentrations of bezafibrate and acesulfame increased although the concentrations of more persistent compounds such as primidone and gabapentin, remained relatively constant. Within the vertical piezometer nest, Fe(II) concentrations increased with depth, allowing for a more rapid turnover of Sulfamethoxazole, but also inhibiting turnover of other compounds such as, benzotriazol, metoprolol and Valsartan. In contrast to previous studies undertaken in more mountainous settings, alluvial attenuation rates at River Erpe were profoundly different. We attribute these findings to both, hydrological characteristics of lowland rivers as well as to the high amounts of labile organic carbon originating from the WWTP effluent. This work further demonstrates that the fate of TrOCs in gaining aquifers adjacent to urban streams is highly complex and demands much more research.

Distribution of persistent organic pollutants (POPS) IN wild Bluefin tuna (Thunnus thynnus) from different FAO capture zones.

PubMed

Chiesa, L M; Labella, G F; Panseri, S; Pavlovic, R; Bonacci, S; Arioli, F

2016-06-01

Residues of environmental contaminants in food represent a concern in food safety programs. In this study, the distribution of persistent organic pollutants (POPs) were evaluated in 79 tuna samples from FAO areas 51 (Indian Ocean), 71 (Pacific Ocean), 34 (Atlantic Ocean), and 37 (Mediterranean Sea). 6 polychlorinated biphenyls (PCBs), 16 organochlorines (OCs) and 7 polybrominated biphenyl ethers (PBDEs) were selected as representative compounds according to EFSA POPs monitoring guidelines. An analytical method, based on Accelerated Solvent Extraction (ASE), with an "in-line" clean-up step and GC-MS/MS detection, was developed, validated and applied. PCBs were detected in all FAO areas, with a prevalence of 100% for most of them. In the FAO area 37, only, all PBDEs were detected. Only 5 OCs were detected. The results showed that POPs contamination of tuna reflects FAO area contamination; in particular FAO area 37 was the most polluted. Moreover, tuna muscle was an appropriate matrix for monitoring contamination and for obtaining information about food safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

Emerging Persistent Organic Pollutants in Chinese Bohai Sea and Its Coastal Regions

PubMed Central

Wang, Yawei; Pan, Yuanyuan

2014-01-01

Emerging persistent organic pollutants (POPs) have widely aroused public concern in recent years. Polybrominated diphenyl ethers (PBDEs) and perfluorooctane sulfonyl fluoride/perfluorooctane sulfonic acid (POSF/PFOS) had been newly listed in Stockholm Convention in 2009, and short chain chlorinated paraffins (SCCPs) and hexabromocyclododecanes (HBCDs) were listed as candidate POPs. Bohai Sea is located in the arms of numbers of industrial cities, the semienclosed location of which makes it an ideal sink of emerging pollutants. In the present paper, latest contamination status of emerging POPs in Bohai Sea was reviewed. According to the literature data, Bohai Sea areas are not heavily contaminated by emerging POPs (PBDE: 0.01–720 ng/g; perfluorinated compounds: 0.1–304 ng/g; SCCPs: 64.9–5510 ng/g; HBCDs: nd-634 ng/g). Therefore, humans are not likely to be under serious risk of emerging POPs exposure through consuming seafood from Bohai Sea. However, the ubiquitous occurrence of emerging POPs in Bohai Sea region might indicate that more work should be done to expand the knowledge about potential risk of emerging POPs pollution. PMID:24688410

Persistent organic pollutants in marine biota of São Pedro and São Paulo Archipelago, Brazil.

PubMed

Dias, Patrick S; Cipro, Caio V Z; Taniguchi, Satie; Montone, Rosalinda C

2013-09-15

Remote islands, such as the São Pedro and São Paulo Archipelago (SPSPA), Brazil, are pristine areas. However, these locations are not exempt from the arrival of anthropogenic agents, such as persistent organic pollutants (POPs). The present study aimed to determine the occurrence and distribution of POPs in the marine biota of the SPSPA. Sample extractions were performed using a microwave-assisted method. The predominant compounds were PCBs and DDTs, which respectively had mean wet weight concentrations of 62.23 and 9.23 ng g(-1) in the tropical two-wing flying fish (Exocoetus volitans), 78.66 and 6.81 ng g(-1) in the brown booby (Sula leucogaster) and 43.40 and 3.03 ng g(-1) in the red rock crab (Grapsus grapsus). Low levels of contaminants suggest a relative degree of isolation. Occurrence and distribution profiles of PCBs support long-range atmospheric transport as the main source of contamination and demonstrate the ubiquity of these pollutants in the marine environment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Interactions of Penicillium griseofulvum with inorganic and organic substrates: vanadium, lead and hexachlorocyclohexane

NASA Astrophysics Data System (ADS)

Ceci, Andrea; Pierro, Lucia; Riccardi, Carmela; Maggi, Oriana; Pinzari, Flavia; Gadd, Geoffrey Michael; Petrangeli Papini, Marco; Persiani, Anna Maria

2015-04-01

Soil is an essential and non-renewable resource for human beings and ecosystems. In recent years, anthropogenic activities mainly related to hydrocarbon fuel combustion, mining and industrial activities have increased the levels of vanadium in the environment, raising concern over its spread. Vanadium may be essential for some bacteria and fungi, but can have toxic effects at high concentrations. The pesticide lindane or γ-hexachlorocyclohexane (γ-HCH) and another two isomers of hexachlorocyclohexane (HCH), α-HCH, and β-HCH, were included as persistent organic pollutants in the Stockholm Convention in 2008, and their worldwide spread and toxic effects on organisms are severe environmental problems. Fungi play important roles in soil and can survive in high concentrations of toxic elements and pesticides by possessing mechanisms for the degradation, utilization and transformation of organic and inorganic substrates. The transformation of potentially toxic elements (PTEs), and degradation of chlorinated pesticides and other persistent organic pollutants may provide environmentally-friendly and economical approaches for environmental management and restoration. In this work, we have investigated the tolerance of a soil fungal species, Penicillum griseofulvum, to different hexachlorocyclohexane (HCH) isomers, α-HCH, β-HCH, δ-HCH and γ-HCH or lindane, and two PTEs, vanadium and lead in relation to growth responses and biotransformation. P. griseofulvum was isolated from soils with high levels of PTEs (including vanadium and lead), and HCH residues. P. griseofulvum was able to tolerate vanadium concentrations up to 5 mM, combinations of 2.5 mM vanadium and lead compounds, and was able to grow in the presence of a 4 mg L-1 mixture of α-HCH, β-HCH, δ-HCH and γ-HCH, and degrade these substrates. Tolerance mechanisms may explain the occurrence of fungi in polluted habitats: their roles in the biotransformation of metals and persistent organic pollutants may provide opportunities for bioremediation. (287 words)

Comparison of degradation between indigenous and spiked bisphenol A and triclosan in a biosolids amended soil.

PubMed

Langdon, Kate A; Warne, Michael Stj; Smernik, Ronald J; Shareef, Ali; Kookana, Rai S

2013-03-01

This study compared the degradation of indigenous bisphenol A (BPA) and triclosan (TCS) in a biosolids-amended soil, to the degradation of spiked labelled surrogates of the same compounds (BPA-d16 and TCS-(13)C12). The aim was to determine if spiking experiments accurately predict the degradation of compounds in biosolids-amended soils using two different types of biosolids, a centrifuge dried biosolids (CDB) and a lagoon dried biosolids (LDB). The rate of degradation of the compounds was examined and the results indicated that there were considerable differences between the indigenous and spiked compounds. These differences were more marked for BPA, for which the indigenous compound was detectable throughout the study, whereas the spiked compound decreased to below the detection limit prior to the study completion. The rate of degradation for the indigenous BPA was approximately 5-times slower than that of the spiked BPA-d16. The indigenous and spiked TCS were both detectable throughout the study, however, the shape of the degradation curves varied considerably, particularly in the CDB treatment. These findings show that spiking experiments may not be suitable to predict the degradation and persistence of organic compounds following land application of biosolids. Copyright © 2013 Elsevier B.V. All rights reserved.

Spatial And Temporal Trends Of Organic Pollutants In Vegetation From Remote And Rural Areas

NASA Astrophysics Data System (ADS)

Bartrons, Mireia; Catalan, Jordi; Penuelas, Josep

2016-05-01

Persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) used in agricultural, industrial, and domestic applications are widely distributed and bioaccumulate in food webs, causing adverse effects to the biosphere. A review of published data for 1977-2015 for a wide range of vegetation around the globe indicates an extensive load of pollutants in vegetation. On a global perspective, the accumulation of POPs and PAHs in vegetation depends on the industrialization history across continents and distance to emission sources, beyond organism type and climatic variables. International regulations initially reduced the concentrations of POPs in vegetation in rural areas, but concentrations of HCB, HCHs, and DDTs at remote sites did not decrease or even increased over time, pointing to a remobilization of POPs from source areas to remote sites. The concentrations of compounds currently in use, PBDEs and PAHs, are still increasing in vegetation. Differential congener specific accumulation is mostly determined by continent—in accordance to the different regulations of HCHs, PCBs and PBDEs in different countries—and by plant type (PAHs). These results support a concerning general accumulation of toxic pollutants in most ecosystems of the globe that for some compounds is still far from being mitigated in the near future.

Petroleomic analysis of the treatment of naphthenic organics in oil sands process-affected water with buoyant photocatalysts.

PubMed

Leshuk, Tim; Peru, Kerry M; de Oliveira Livera, Diogo; Tripp, Austin; Bardo, Patrick; Headley, John V; Gu, Frank

2018-05-10

The persistence of toxicity associated with the soluble naphthenic organic compounds (NOCs) of oil sands process-affected water (OSPW) implies that a treatment solution may be necessary to enable safe return of this water to the environment. Due to recent advances in high-resolution mass spectrometry (HRMS), the majority of the toxicity of OSPW is currently understood to derive from a subset of toxic classes, comprising only a minority of the total NOCs. Herein, oxidative treatment of OSPW with buoyant photocatalysts was evaluated under a petroleomics paradigm: chemical changes across acid-, base- and neutral-extractable organic fractions were tracked throughout the treatment with both positive and negative ion mode electrospray ionization (ESI) Orbitrap MS. Elimination of detected OS + and NO + classes of concern in the earliest stages of the treatment, along with preferential degradation of high carbon-numbered O 2 - acids, suggest that photocatalysis may detoxify OSPW with higher efficiency than previously thought. Application of petroleomic level analysis offers unprecedented insights into the treatment of petroleum impacted water, allowing reaction trends to be followed across multiple fractions and thousands of compounds simultaneously. Copyright © 2018 Elsevier Ltd. All rights reserved.

Chemical quality of the Saw Mill River, Westchester County, New York, 1981-83

USGS Publications Warehouse

Rogers, R.J.

1984-01-01

Surface waters, bottom sediments and coatings formed on artificial substrates (ceramic tiles) were analyzed to evaluate the chemical quality of the Saw Mill River, New York. Heavy metals, nutrients, and organic contaminants were studied. Dissolved orthophosphate concentrations were highest in the lower third of the river. Dissolved manganese was the only metal to exceed U.S. Environmental Protection Agency water-quality criteria. Arsenic, cadmium, copper, lead, and zinc concentrations were highest in waters from the lowest 4 river miles. Concentrations of copper, lead, and zinc in bottom sediments from the lowest 3 river miles were greater than in upstream sediments. Concentrations of nine heavy metals were higher on tiles emplaced below river mile 3 than on tiles upstream. Few organic compounds were detected in the water column; none persisted at all sites. Chlordane, DDD, DDE, DDT, dieldrin, and polychlorinated biphenyls (PCB's) were found in bottom sediments throughout the basin. PCB concentrations were highest in the lowest 6 river miles; the other organic compounds exhibited no spatial patterns. Polynuclear aromatic hydrocarbons were most abundant in bottom sediments from the lowest 2 river miles. Collectively the distribution of contaminants indicates that river quality deteriorates in the lower, more heavily urbanized reach. (USGS)

Photochemical Assessment Monitoring Stations (PAMS)

EPA Pesticide Factsheets

Photochemical Assessment Monitoring Stations (PAMS). This file provides information on the numbers and distribution (latitude/longitude) of air monitoring sites which measure ozone precursors (approximately 60 volatile hydrocarbons and carbonyl), as required by the 1990 Clean Air Act Amendments, in areas with persistently high ozone levels (mostly large metropolitan areas). In these areas, the States have established ambient air monitoring sites which collect and report detailed data for volatile organic compounds, nitrogen oxides, ozone and meteorological parameters. This file displays 199 monitoring sites reporting measurements for 2010. A wide range of related monitoring site attributes is also provided.

Review of 'emerging' organic contaminants in biosolids and assessment of international research priorities for the agricultural use of biosolids.

PubMed

Clarke, Bradley O; Smith, Stephen R

2011-01-01

A broad spectrum of organic chemicals is essential to modern society. Once discharged from industrial, domestic and urban sources into the urban wastewater collection system they may transfer to the residual solids during wastewater treatment and assessment of their significance and implications for beneficial recycling of the treated sewage sludge biosolids is required. Research on organic contaminants (OCs) in biosolids has been undertaken for over thirty years and the increasing body of evidence demonstrates that the majority of compounds studied do not place human health at risk when biosolids are recycled to farmland. However, there are 143,000 chemicals registered in the European Union for industrial use and all could be potentially found in biosolids. Therefore, a literature review of 'emerging' OCs in biosolids has been conducted for a selection of chemicals of potential concern for land application based upon human toxicity, evidence of adverse effects on the environment and endocrine disruption. To identify monitoring and research priorities the selected chemicals were ranked using an assessment matrix approach. Compounds were evaluated based upon environmental persistence, human toxicity, evidence of bioaccumulation in humans and the environment, evidence of ecotoxicity and the number and quality of studies focussed on the contaminant internationally. The identified chemicals of concern were ranked in decreasing order of priority: perfluorinated chemicals (PFOS, PFOA); polychlorinated alkanes (PCAs), polychlorinated naphthalenes (PCNs); organotins (OTs), polybrominated diphenyl ethers (PBDEs), triclosan (TCS), triclocarban (TCC); benzothiazoles; antibiotics and pharmaceuticals; synthetic musks; bisphenol A, quaternary ammonium compounds (QACs), steroids; phthalate acid esters (PAEs) and polydimethylsiloxanes (PDMSs). A number of issues were identified and recommendations for the prioritisation of further research and monitoring of 'emerging' OCs for the agricultural use of biosolids are provided. In particular, a number of 'emerging' OCs (PFOS, PFOA and PCAs) were identified for priority attention that are environmentally persistent and potentially toxic with unique chemical properties, or are present in large concentrations in sludge, that make it theoretically possible for them to enter human and ecological food-chains from biosolids-amended soil. Copyright © 2010 Elsevier Ltd. All rights reserved.

Pesticides in Ground Water of the Maryland Coastal Plain

USGS Publications Warehouse

Denver, Judith M.; Ator, Scott W.

2006-01-01

Selected pesticides are detectable at low levels (generally less than 0.1 microgram per liter) in unconfined ground water in many parts of the Maryland Coastal Plain. Samples were recently collected (2001-04) from 47 wells in the Coastal Plain and analyzed for selected pesticides and degradate compounds (products of pesticide degradation). Most pesticide degradation occurs in the soil zone before infiltration to the water table, and degradates of selected pesticides were commonly detected in ground water, often at higher concentrations than their respective parent compounds. Pesticides and their degradates often occur in ground water in mixtures of multiple compounds, reflecting similar patterns in usage. All measured concentrations in ground water were below established standards for drinking water, and nearly all were below other health-based guidelines. Although drinking-water standards and guidelines are typically much higher than observed concentrations in ground water, they do not exist for many detected compounds (particularly degradates), or for mixtures of multiple compounds. The distribution of observed pesticide compounds reflects known usage patterns, as well as chemical properties and environmental factors that affect the fate and transport of these compounds in the environment. Many commonly used pesticides, such as glyphosate, pendimethalin, and 2,4-D were not detected in ground water, likely because they were sorbed onto organic matter or degraded in the soil zone. Others that are more soluble and (or) persistent, like atrazine, metolachlor, and several of their degradates, were commonly detected in ground water where they have been used. Atrazine, for example, an herbicide used primarily on corn, was most commonly detected in ground water on the Eastern Shore (where agriculture is common), particularly where soils are well drained. Conversely, dieldrin, an insecticide previously used heavily for termite control, was detected only on the Western Shore, where urban land is more common. Use of dieldrin was suspended in 1987, but this compound is relatively persistent in the environment, and several decades are typically required for ground water to move completely through the surficial aquifer. U.S. Department of the Interior U.S. Geological Survey USGS Fact Sheet FS 2006-3119 2006 Location of the Maryland Coastal Plain.

Human exposure, biomarkers, and fate of organotins in the environment.

PubMed

Okoro, Hussein K; Fatoki, Olalekan S; Adekola, Folahan A; Ximba, Bhekumusa J; Snyman, Reinette G; Opeolu, Beatrice

2011-01-01

Organotin compounds result from the addition of organic moieties to inorganic tin.Thus, one or more tin-carbon bonds exist in each organotin molecule. The organo-tin compounds are ubiquitous in the environment. Organotin compounds have many uses, including those as fungicides and stabilizers in plastics, among others in industry. The widespread use of organotins as antifouling agents in boat paints has resulted in pollution of freshwater and marine ecosystems. The presence of organotin compounds in freshwater and marine ecosystems is now understood to be a threat, because of the amounts found in water and the toxicity of some organotin compounds to aquatic organisms, and perhaps to humans as well. Organotin com-pounds are regarded by many to be global pollutants of a stature similar to biphenyl,mercury, and the polychlorinated dibenzodioxins. This stature results from the high toxicity, persistence, bioaccumulation, and endocrine disruptive features of even very low levels of selected organotin compounds.Efforts by selected governmental agencies and others have been undertaken to find a global solution to organotin pollution. France was the first country to ban the use of the organotins in 1980. This occurred before the international maritime organization (IMO) called for a global treaty to ban the application of tributyltin (TBT)-based paints. In this chapter, we review the organotin compounds with emphasis on the human exposure, fate, and distribution of them in the environment. The widespread use of the organotins and their high stability have led to contamination of some aquatic ecosystems. As a result, residues of the organotins may reach humans via food consumption. Notwithstanding the risk of human exposure, only limited data are available on the levels at which the organotins exist in foodstuffs consumed by humans. Moreover, the response of marine species to the organotins, such as TBT, has not been thoroughly investigated. Therefore, more data on the organotins and the consequences of exposure to them are needed. In particular, we believe the following areas need attention: expanded toxicity testing in aquatic species, human exposure, human body burdens, and the research to identify biomarkers for testing the toxicity of the organotins to marine invertebrates.

Effect of persistent trace compounds in landfill gas on engine performance during energy recovery: a case study.

PubMed

Sevimoğlu, Orhan; Tansel, Berrin

2013-01-01

Performances of gas engines operated with landfill gas (LFG) are affected by the impurities in the LFG, reducing the economic viability of energy recovery. The purpose of this study was to characterize the trace compounds in the LFG at the Odayeri Landfill, Istanbul, Turkey which is used for energy recovery. Composite gas samples were collected and analyzed for trace compounds (hydrocarbons, siloxanes, and volatile halogenated hydrocarbons) over a 3-year period. Trace compounds entering the gas engines, their impact on the engine performance were evaluated. The operational problems included deposit formation in the combustion chamber, turbocharger, and intercooler of engine before the scheduled maintenance times. High levels of hydrogen sulfide, as well as chlorinated and fluorinated compounds cause corrosion of the engine parts and decrease life of the engine oils. Persistence of siloxanes results in deposit formation, increasing engine maintenance costs. Pretreatment of LFG is necessary to protect the engines at the waste-to-energy facilities with persistence levels of siloxanes and volatile halogenated hydrocarbons. Copyright © 2012 Elsevier Ltd. All rights reserved.

Biological monitoring of Persistent Organic Pollutants in human milk in Israel.

PubMed

Wasser, Janice; Berman, Tamar; Lerner-Geva, Liat; Grotto, Itamar; Rubin, Lisa

2015-10-01

The Stockholm Convention on Persistent Organic Pollutants (POPs) aims to eliminate or restrict the production and use of POPs around the globe. The Ministry of Health, collaborating with the Ministry of Environmental Protection, measured the exposure of the population to POPs as part of the WHO-coordinated exposure study. Human milk, with a relatively high fat content is a preferred matrix for the monitoring of exposure. Donors of breast milk were recruited from three hospitals after signing informed consent forms. Breast milk was collected from 52 primipara women, aged 23-35, living in Israel for the last 10 years who gave birth to singleton full term healthy infants. Samples, collected at 3-17 weeks postpartum, were stored at -20 °C until sent to the WHO Reference Laboratory, State Laboratory for Chemical and Veterinary Analysis of Food (CVUA), in Frieburg, Germany for a single pooled analysis. Mothers were provided with the pooled analysis results. Out of over 50 Persistent Organic Pollutants listed in the analysis, 16, including aldrin, endrin, parlar and mirex were not found at detectable levels in the Israeli pooled sample. For the indicator compounds found at detectable levels, most were lower than those reported in European countries. Since 1982, levels of POPs contamination as measured in breast milk have declined significantly. This is likely due to restrictions on agricultural, industrial, and other uses of many POPs in Israel. Ongoing biomonitoring in Israel and inter-ministerial collaboration supports the elimination of POPs in the environment and human milk. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ecotoxicity and biodegradability of new brominated flame retardants: a review.

PubMed

Ezechiáš, M; Covino, S; Cajthaml, T

2014-12-01

Brominated flame retardants (BFRs) have been routinely used as additives in a number of consumer products for several decades in order to reduce the risk of fire accidents. Concerns about the massive use of these substances have increased due to their possible toxicity, endocrine disrupting properties and occurrence in almost all the environmental compartments, including humans and wildlife organisms. Several conventional BFRs (e.g. polybrominated diphenylethers (PBDE)) have been included in the list of Persistent Organic Pollutants and their use has been restricted because of their established toxicity and environmental persistence. Over the past few years, these compounds have been replaced with "new" BFRs (NBFRs). Despite the fact that NBFRs are different chemical molecules than traditional BFRs, most of physical-chemical properties (e.g. aromatic moiety, halogen substitution, lipophilic character) are common to both groups; therefore, their fate in the environment is potentially similar to the banned BFRs. Therefore, this article has been compiled to summarize the published scientific data regarding the biodegradability of the most widely used NBFRs, a key factor in their potential persistency in the environment, and their ecotoxicological effects on humans and test organisms. The data reviewed here document that the mechanisms through NBFRs exibit their ecotoxicity and the processes leading to their biotransformation in the environment are still poorly understood. Thus emphasis is placed on the need for further research in these areas is therefore emphasized, in order to avoid the massive use of further potentially harmful and recalcitrant substances of anthropogenic origin. Copyright © 2014 Elsevier Inc. All rights reserved.

Chlorinated hydrocarbons in the marine environment. A report prepared by the Panel on Monitoring Persistent Pesticides in the Marine Environment of the Committee on Oceanography

USGS Publications Warehouse

,; Goldberg, E.D.; Butler, P.; Meier, P.; Menzel, D.; Paulik, G.; Risebrough, R.; Stickel, L.F.

1971-01-01

SUMMARY AND RECOMMENDATIONS : The oceans are an ultimate accumulation site for the persistent chlorinated hydrocarbons. As much as 25 percent of the DDT compounds produced to date may have been transferred to the sea. The amount of DDT compounds in the marine biota is estimated to be less than 0.1 percent of total production, yet this amount has produced a demonstrable impact upon the marine environment. Populations of fish-eating birds have experienced reproductive failure and decline. With continued accumulations of persistent chlorinated hydrocarbons in the marine ecosystem, additional species will be threatened. Continued release of these pollutants to the environment can only accelerate the accumulation of unacceptable levels of persistent chlorinated hydrocarbons in the tissues of marine food fish. Certain risks in the utilization of chlorinated hydrocarbons are especially hard to quantify, but they require serious consideration. The rate at which such substances degrade to harmless products in the marine system is unknown; the half-lives of some of the more persistent materials are certainly of the order of years, and perhaps even of decades or centuries. If most of the remaining 75 percent of the persistent chlorinated hydrocarbons is now in reservoirs that will in time transfer their contents to the sea, we may expect an increased level of these substances in marine organisms, despite future improvements of manufacturing practices. In fact, if these compounds degrade with half-lives of decades or longer, there will be no opportunity to redress the consequences. The more the problems are studied, the more unexpected effects are identified. In view of the findings of the past decade, our prediction of the potential hazards of chlorinated hydrocarbons in the marine environment may be vastly underestimated. The Panel makes the following recommendations, which will be developed and expanded in the remainder of the report: ? A massive national effort should be made immediately to effect a drastic reduction of the escape of persistent toxicants into the environment, with the ultimate aim of achieving virtual cessation in the shortest possible time. ? Programs should be designed both to determine the rates of entry of each pollutant into the marine environment and to make base-line determinations of the distribution of the pollutants among the components of that environment, These should be followed by a program of monitoring long-term trends in order to record progress and to document possible disaster. ? The laws relating to the registration of chemical substances and the release of production figures by government should be examined and perhaps revised in light of evidence of environmental deterioration caused by some of these substances.

Current status of persistent organic pesticides residues in air, water, and soil, and their possible effect on neighboring countries: a comprehensive review of India.

PubMed

Yadav, Ishwar Chandra; Devi, Ningombam Linthoingambi; Syed, Jabir Hussain; Cheng, Zhineng; Li, Jun; Zhang, Gan; Jones, Kevin C

2015-04-01

Though the use of pesticides has offered significant economic benefits by enhancing the production and yield of food and fibers and the prevention of vector-borne diseases, evidence suggests that their use has adversely affected the health of human populations and the environment. Pesticides have been widely distributed and their traces can be detected in all areas of the environment (air, water and soil). Despite the ban of DDT and HCH in India, they are still in use, both in domestic and agricultural settings. In this comprehensive review, we discuss the production and consumption of persistent organic pesticides, their maximum residual limit (MRL) and the presence of persistent organic pesticides in multicomponent environmental samples (air, water and soil) from India. In order to highlight the global distribution of persistent organic pesticides and their impact on neighboring countries and regions, the role of persistent organic pesticides in Indian region is reviewed. Based on a review of research papers and modeling simulations, it can be concluded that India is one of the major contributors of global persistent organic pesticide distribution. This review also considers the health impacts of persistent organic pesticides, the regulatory measures for persistent organic pesticides, and the status of India's commitment towards the elimination of persistent organic pesticides. Copyright © 2014 Elsevier B.V. All rights reserved.

Recent trends in water analysis triggering future monitoring of organic micropollutants.

PubMed

Schmidt, Torsten C

2018-03-21

Water analysis has been an important area since the beginning of analytical chemistry. The focus though has shifted substantially: from minerals and the main constituents of water in the time of Carl Remigius Fresenius to a multitude of, in particular, organic compounds at concentrations down to the sub-nanogram per liter level nowadays. This was possible only because of numerous innovations in instrumentation in recent decades, drivers of which are briefly discussed. In addition to the high demands on sensitivity, high throughput by automation and short analysis times are major requirements. In this article, some recent developments in the chemical analysis of organic micropollutants (OMPs) are presented. These include the analysis of priority pollutants in whole water samples, extension of the analytical window, in particular to encompass highly polar compounds, the trend toward more than one separation dimension before mass spectrometric detection, and ways of coping with unknown analytes by suspect and nontarget screening approaches involving high-resolution mass spectrometry. Furthermore, beyond gathering reliable concentration data for many OMPs, the question of the relevance of such data for the aquatic system under scrutiny is becoming ever more important. To that end, effect-based analytics can be used and may become part of future routine monitoring, mostly with a focus on adverse effects of OMPs in specific test systems mimicking environmental impacts. Despite advances in the field of water analysis in recent years, there are still many challenges for further analytical research. Graphical abstract Recent trends in water analysis of organic micropollutants that open new opportunities in future water monitoring. HRMS high-resolution mass spectrometry, PMOC persistent mobile organic compounds.

Occurrence, fate, and ecosystem implications of endocrine active compounds in select rivers of Minnesota

NASA Astrophysics Data System (ADS)

Writer, J.; Keefe, S.; Barber, L. B.; Brown, G.; Schoenfuss, H.; Kiesling, R.; Gray, J. L.

2009-12-01

Select endocrine active compounds (EACs) were measured in four rivers in southern Minnesota. Additionally, caged and wild fish were assessed for indication of endocrine disruption using plasma vitellogenin and histopathology. Low concentrations of EACs were identified in all rivers, as was elevated plasma vitellogenin in caged and wild fish, indicating potential endocrine disruption. To evaluate the persistence of these compounds in small rivers, a tracer study was performed on one of the rivers (Redwood River) using Lagrangian sampling coupled with hydrologic modeling incorporating transient storage. Mass exchange (transient storage, sorption) and degradation were approximated as pseudo first order processes, and in-stream removal rates were then computed by comparing conservative tracer concentrations to organic compound concentrations. Production of estrone and 4-nonylphenol in the studied reach as a result of biochemical transformation from their parent compounds (17β-estradiol and alkylphenolpolyethoxylates, respectively) was quantified. The distance required for 17β-estradiol and nonylphenol to undergo a 50% reduction in concentration was >2 km and >10 km, respectively. These results indicate that EACs are transported several kilometers downstream from discharge sources and therefore have the potential of adversely impacting the lotic ecosystem over these distances.

Stabilization of biosolids with nanoscale zero-valent iron (nZVI)

NASA Astrophysics Data System (ADS)

Li, Xiao-qin; Brown, Derick G.; Zhang, Wei-xian

2007-04-01

Biosolids are the treated organic residuals, also known as sludge, that are generated from domestic wastewater treatment plants. According to the USEPA, over 7 millions tons (dry weight) of biosolids are generated every year in the US by more than the 16,000 wastewater treatment plants and a large portion of these biosolids is disposed on land. Nuisance odors, the potential of pathogen transmission, and presence of toxic and persistent organic chemicals and metals in biosolids have for the most part limited the use of land applications. This paper presents zero-valent iron nanoparticles (1-100 nm) for the treatment and stabilization of biosolids. Iron nanoparticles have been shown to form stable and nonvolatile surface complexes with malodorous sulfur compounds such as hydrogen sulfide and methyl sulfides, degrade persistent organic pollutants such as PCBs and chlorinated pesticides, and sequestrate toxic metal ions such as mercury and lead. The end products from the nanoparticle reactions are iron oxides and oxyhydroxides, similar to the ubiquitous iron minerals in the environment. Due to the large surface area and high surface reactivity, only a relatively low dose (<0.1% wt) of iron nanoparticles is needed for effective biosolids stabilization. The iron nanoparticle technology may thus offer an economically and environmentally sustainable and unique solution to one of the most vexing environmental problems.

Persistent organic pollutants in selected fishes of the Gulf of Finland

NASA Astrophysics Data System (ADS)

Järv, Leili; Kiviranta, Hannu; Koponen, Jani; Rantakokko, Panu; Ruokojärvi, Päivi; Radin, Maia; Raid, Tiit; Roots, Ott; Simm, Mart

2017-07-01

Fish samples of Baltic herring, sprat, flounder, perch, salmon, and river lamprey were collected from the Gulf of Finland in 2013 and 2014 with the aim to get an overview of the occurrence of pollutants in fish caught in Estonian waters. The content of non-dioxin-like polychlorinated biphenyls (ndl PCBs), polybrominated diphenyl ethers (PBDEs), organic tin (OT) and perfluorocompounds (PFAS) are examined and discussed in the study. The results revealed that potentially higher content of organo-tin compounds, perfluorocompounds and polybrominated diphenyl ethers in Baltic herring, salmon and river lamprey may cause concern regarding human exposure. It is important to link pollutant content to lipid content of fish taking into account their seasonal variation in different age classes.

Effects of urbanization and long-term rainfall on the occurrence of organic compounds and trace elements in reservoir sediment cores, streambed sediment, and fish tissue from the Santa Ana River basin, California, 1998

USGS Publications Warehouse

Burton, Carmen A.

2002-01-01

Organcochlorine compounds, semivolatile-organic compounds (SVOC), and trace elements were analyzed in reservoir sediment cores, streambed sediment, and fish tissue in the Santa Ana River Basin as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Three reservoirs were sampled in areas that have different degrees of urbanization. Streambed sediment and fish tissue collected at 12 sites were divided into two groups, urban and nonurban. More organochlorine compounds were detected in reservoir sediment cores, streambed sediment and fish tissue, and at higher concentrations at urban sites than at nonurban sites. At all sites, except West Street Basin, concentrations of organochlorine compounds were lower than the probable-effect concentration (PEC). At the highly urbanized West Street Basin, chlordane and p,p'-DDE exceeded the PEC throughout the historical record. The less stringent threshold-effect concentration (TEC) was exceeded for six compounds at eight sites. Most of the organochlorine compounds detected in streambed sediment and fish tissue were at urban sites on the Santa Ana River as opposed to its tributaries, suggesting accumulation and persistence in the river. More SVOCs were detected in reservoir sediment cores and streambed sediment, and at higher concentrations, at urban sites than at nonurban sites. At all the sites, except West Street Basin, concentrations of SVOCs were lower than the PEC. At West Street Basin, chrysene, pyrene, and total polycyclic-aromatic hydrocarbons exceeded the PEC throughout the historical record. The TEC was exceeded for 10 compounds at 3 sites. Most of the SVOCs were detected in streambed sediment at urban sites on tributaries to the Santa Ana River rather than the mainstem itself. The less frequent occurrence and lower concentrations in the Santa Ana River suggest that SVOCs are less persistent than organochlorine compounds, possibly as a result of volatization, gradation, or dilution. Most trace-element detections in reservoir sediment cores and streambed sediment were at urban sites, and the concentrations were generally higher than at nonurban sites. Lead and zinc exceeded their PECs at West Street Basin throughout the historical record; copper exceeded its PEC at Canyon Lake, an area of urban growth. The TEC was exceeded for 10 compounds at 11 sites. Frequency of detection and concentration did not differ between tributary and Santa Ana River sites, which may be attributed to the fact that trace elements occur naturally. Four trace elements (arsenic, copper, mercury, and selenium) had higher concentrations in fish tissue at nonurban sites than at urban sites. Concentrations decreased over time for organochlorine compounds at all three reservoirs, probably a result of the discontinued use of many of the compounds. Decreasing trends in SVOCs and trace elements were observed at West Street Basin, but increasing trends were observed at Canyon Lake. Concentrations of organochlorine compounds, SVOCs, and trace elements were higher during periods of above average rainfall at both West Street Basin and Canyon Lake.

Tracking persistent pharmaceutical residues from municipal sewage to drinking water

NASA Astrophysics Data System (ADS)

Heberer, Thomas

2002-09-01

In urban areas such as Berlin (Germany) with high municipal sewage water discharges and low surface water flows there is a potential risk of drinking water contamination by polar organic compounds when groundwater recharge is used in drinking water production. Thus, some pharmaceutically active compounds (PhACs) are not eliminated completely in the municipal sewage treatment plants (STPs) and they are discharged as contaminants into the receiving waters. In terms of several monitoring studies carried out in Berlin between 1996 and 2000, PhACs such as clofibric acid, diclofenac, ibuprofen, propyphenazone, primidone and carbamazepine were detected at individual concentrations up to the μg/l-level in influent and effluent samples from STPs and in all surface water samples collected downstream from the STPs. Under recharge conditions, several compounds were also found at individual concentrations up to 7.3 μg/l in samples collected from groundwater aquifers near to contaminated water courses. A few of the PhACs were also identified at the ng/l-level in Berlin tap water samples.

Do pharmaceuticals, pathogens, and other organic waste water compounds persist when waste water is used for recharge?

USGS Publications Warehouse

Cordy, Gail E.; Duran, Norma L.; Bouwer, Herman; Rice, Robert C.; Furlong, Edward T.; Zaugg, Steven D.; Meyer, Michael T.; Barber, Larry B.; Kolpin, Dana W.

2004-01-01

A proof-of-concept experiment was devised to determine if pharmaceuticals and other organic waste water compounds (OWCs), as well as pathogens, found in treated effluent could be transported through a 2.4 m soil column and, thus, potentially reach ground water under recharge conditions similar to those in arid or semiarid climates. Treated effluent was applied at the top of the 2.4 m long, 32.5 cm diameter soil column over 23 days, Samples of the column inflow were collected from the effluent storage tank at the beginning (Tbegin) and end (Tend) of the experiment, and a sample of the soil column drainage at the base of the column (Bend) was collected at the end of the experiment. Samples were analyzed for 131 OWCs including veterinary and human antibiotics, other prescription and nonprescription drugs, widely used household and industrial chemicals, and steroids and reproductive hormones, as well as the pathogens Salmonella and Legionella. Analytical results for the two effluent samples taken at the beginning (Tbegin) and end (Tend) of the experiment indicate that the number of OWCs detected in the column inflow decreased by 25% (eight compounds) and the total concentration of OWCs decreased by 46% while the effluent was in the storage tank during the 23-day experiment. After percolating through the soil column, an additional 18 compounds detected in Tend (67% of OWCs) were no longer detected in the effluent (Bend) and the total concentration of OWCs decreased by more than 70%. These compounds may have been subject to transformation (biotic and abiotic), adsorption, and (or) volatilization in the storage tank and during travel through the soil column. Eight compounds—carbamazapine; sulfamethoxazole; benzophenone; 5-methyl-1H-benzotriazole; N,N-diethyltoluamide; tributylphosphate; tri(2-chloroethyl) phosphate; and cholesterol—were detected in all three samples indicating they have the potential to reach ground water under recharge conditions similar to those in arid and semiarid climates. Results from real-time polymerase chain reactions demonstrated the presence of Legionella in all three samples. Salmonella was detected only in Tbegin, suggesting that the bacteria died off in the effluent storage tank over the period of the experiment. This proof-of-concept experiment demonstrates that, under recharge conditions similar to those in arid or semiarid climates, some pharmaceuticals, pathogens, and other OWCs can persist in treated effluent after soil-aquifer treatment.

Effects of effluent organic matter characteristics on the removal of bulk organic matter and selected pharmaceutically active compounds during managed aquifer recharge: Column study

NASA Astrophysics Data System (ADS)

Maeng, Sung Kyu; Sharma, Saroj K.; Abel, Chol D. T.; Magic-Knezev, Aleksandra; Song, Kyung-Guen; Amy, Gary L.

2012-10-01

Soil column experiments were conducted to investigate the effects of effluent organic matter (EfOM) characteristics on the removal of bulk organic matter (OM) and pharmaceutically active compounds (PhACs) during managed aquifer recharge (MAR) treatment processes. The fate of bulk OM and PhACs during an MAR is important to assess post-treatment requirements. Biodegradable OM from EfOM, originating from biological wastewater treatment, was effectively removed during soil passage. Based on a fluorescence excitation-emission matrix (F-EEM) analysis of wastewater effluent-dominated (WWE-dom) surface water (SW), protein-like substances, i.e., biopolymers, were removed more favorably than fluorescent humic-like substances under oxic compared to anoxic conditions. However, there was no preferential removal of biopolymers or humic substances, determined as dissolved organic carbon (DOC) observed via liquid chromatography with online organic carbon detection (LC-OCD) analysis. Most of the selected PhACs exhibited removal efficiencies of greater than 90% in both SW and WWE-dom SW. However, the removal efficiencies of bezafibrate, diclofenac and gemfibrozil were relatively low in WWE-dom SW, which contained more biodegradable OM than did SW (copiotrophic metabolism). Based on this study, low biodegradable fractions such as humic substances in MR may have enhanced the degradation of diclofenac, gemfibrozil and bezafibrate by inducing an oligotrophic microbial community via long term starvation. Both carbamazepine and clofibric acid showed persistent behaviors and were not influenced by EfOM.

Assessment of persistent organic pollutants levels in blood samples from Quintana Roo, Mexico.

PubMed

Antonio, Trejo-Acevedo; Edith, Rivero-Pérez Norma; Rogelio, Flores-Ramírez; Fernando, Díaz-Barriga; Catalina, Ochoa Angeles; Nelinho, Pérez-Maldonado Iván

2013-06-01

The Stockholm Convention on persistent organic pollutants (POPs) sought to determine baseline exposures to POPs in the general population; however, in developing countries, exposure to these chemicals in hot spots may be an issue of public health considering its magnitude. Therefore, the aim of this study was to assess the levels of POPs in the blood of children living in three communities in the Southeastern Region of Mexico. During 2007, we studied a total of 96 healthy children (aged 6-12 years). Quantitative analyses were performed using gas chromatography coupled with mass spectrometry. High levels of p,p'-DDT and its principal metabolite, p,p'-DDE, were found in the blood of children living in the three communities studied, the levels ranged from 463.5 to 9046.3 ng/g lipid and from 490.8 to 57,712.4 ng/g lipid for DDT and DDE, respectively. In addition, high levels of lindane (γ-HCH) were found, with mean levels ranging between 575.4 and 6580.6 ng/g lipid. Moreover, children living in the study region were also exposed to polychlorinated biphenyls (PCBs), and the levels of these compounds in the blood of children were very similar between the communities with mean levels of around 3000 ng/g lipid (total PCBs). In conclusion, we demonstrated that children living in the studied communities were exposed to complex chemical mixtures (DDT, DDE, lindane and PCBs) rather than to individual compounds. Therefore, in future studies it is important to understand the potential interactions between the components of these mixtures. Copyright © 2012 Elsevier GmbH. All rights reserved.

Passive sampling to measure baseline dissolved persistent organic pollutant concentrations in the water column of the Palos Verdes Shelf Superfund site.

PubMed

Fernandez, Loretta A; Lao, Wenjian; Maruya, Keith A; White, Carmen; Burgess, Robert M

2012-11-06

Passive sampling was used to deduce water concentrations of persistent organic pollutants (POPs) in the vicinity of a marine Superfund site on the Palos Verdes Shelf, California, USA. Precalibrated solid phase microextraction (SPME) fibers and polyethylene (PE) strips that were preloaded with performance reference compounds (PRCs) were codeployed for 32 d along an 11-station gradient at bottom, surface, and midwater depths. Retrieved samplers were analyzed for DDT congeners and their breakdown products (DDE, DDD, DDMU, and DDNU) and 43 PCB congeners using GC-EI- and NCI-MS. PRCs were used to calculate compound-specific fractional equilibration achieved in situ for the PE samplers, using both an exponential approach to equilibrium (EAE) and numerical integration of Fickian diffusion (NI) models. The highest observed concentrations were for p,p'-DDE, with 2200 and 990 pg/L deduced from PE and SPME, respectively. The difference in these estimates could be largely attributed to uncertainty in equilibrium partition coefficients, unaccounted for disequilibrium between samplers and water, or different time scales over which the samplers average. The concordance between PE and SPME estimated concentrations for DDE was high (R(2) = 0.95). PCBs were only detected in PE samplers, due to their much larger size. Near-bottom waters adjacent to and down current from sediments with the highest bulk concentrations exhibited aqueous concentrations of DDTs and PCBs that exceeded Ambient Water Quality Criteria (AWQC) for human and aquatic health, indicating the need for future monitoring to determine the effectiveness of remedial activities taken to reduce adverse effects of contaminated surface sediments.

Transactivation potencies of Baikal seal constitutive active/androstane receptor by persistent organic pollutants and brominated flame retardants.

PubMed

Sakai, Hiroki; Kim, Eun-Young; Petrov, Evgeny A; Tanabe, Shinsuke; Iwata, Hisato

2009-08-15

To characterize ligand-dependent transcriptional activation of constitutive active/androstane receptor (CAR) in aquatic mammals, transactivation potentials of the Baikal seal (Pusa sibirica) CAR (bsCAR) by environmental pollutants, including persistent organic pollutants (POPs) and brominated flame retardants (BFRs), were investigated using an in vitro reporter gene assay, and compared with those of the mouse CAR (mCAR). Measurement of luciferase reporter gene activities demonstrated that the seal CAR was activated by POPs, including a technical mixture of PCBs (Kanechlor-500), certain individual PCB congeners, DDT compounds, and trans-nonachlor. No or slight bsCAR-dependent activity was detected in experiments with PBDE congeners and HBCDs. The interspecies comparison of lowest observed effect concentration (LOEC) for CAR transactivation byeach compound revealed that bsCAR responds more sensitively to PCBs than mCAR. In addition, bsCAR was weakly deactivated by PBDE99, whereas mCAR transcriptional activity decreased weakly by PBDE100, PBDE154, and PBDE187. Comparison of reporter gene activities by the congeners with the same IUPAC numbers among PCBs and PBDEs revealed that both bsCAR and mCAR were not activated by PBDE99 and PBDE153, but were activated by PCB99 and PCB153. The small ligand-binding pocket in CAR may contribute to difference in response between PCBs and PBDEs. Given that ethical rationale prevents dosing studies with such organohalogens in aquatic mammals, our in vitro assay system constructed with CAR cDNA from a species of interest provides a useful and realistic alternative approach in ecotoxicology.

Effects of biologically-active chemical mixtures on fish in a wastewater-impacted urban stream

USGS Publications Warehouse

Barber, Larry B.; Brown, Gregory K.; Nettesheim, Todd G.; Murphy, Elizabeth W.; Bartell, Stephen E.; Schoenfuss, Heiko L.

2011-01-01

Stream flow in urban aquatic ecosystems often is maintained by water-reclamation plant (WRP) effluents that contain mixtures of natural and anthropogenic chemicals that persist through the treatment processes. In effluent-impactedstreams, aquatic organisms such as fish are continuously exposed to biologically-activechemicals throughout their life cycles. The North Shore Channel of the Chicago River (Chicago, Illinois) is part of an urban ecosystem in which > 80% of the annual flow consists of effluent from the North Side WRP. In this study, multiple samplings of the effluent and stream water were conducted and fish (largemouth bass and carp) were collected on 2 occasions from the North Shore Channel. Fish also were collected once from the Outer Chicago Harbor in Lake Michigan, a reference site not impacted by WRP discharges. Over 100 organic chemicals with differing behaviors and biological effects were measured, and 23 compounds were detected in all of the water samples analyzed. The most frequently detected and highest concentration (> 100 μg/L) compounds were ethylenediaminetetraacetic acid and 4-nonylphenolmono-to-tetraethoxycarboxylic acids. Other biologically-activechemicals including bisphenol A, 4-nonylphenol, 4-nonylphenolmono-to-tetraethoxylates, 4-tert-octylphenol, and 4-tert-octylphenolmono-to-tetraethoxylates were detected at lower concentrations (cis-androsterone were detected at even lower concentrations (< 0.005 μg/L). There were slight differences in concentrations between the North Side WRP effluent and the North Shore Channel, indicating minimal in-stream attenuation. Fish populations are continuously exposed to mixtures of biologically-activechemicals because of the relative persistency of the chemicals with respect to stream hydraulic residence time, and the lack of a fresh water source for dilution. The majority of male fish exhibited vitellogenin induction, a physiological response consistent with exposure to estrogenic compounds. Tissue-level signs of reproductive disruption, such as ovatestis, were not observed.

Effects of biologically-active chemical mixtures on fish in a wastewater-impacted urban stream

USGS Publications Warehouse

Barber, L.B.; Brown, G.K.; Nettesheim, T.G.; Murphy, E.W.; Bartell, S.E.; Schoenfuss, H.L.

2011-01-01

Stream flow in urban aquatic ecosystems often is maintained by water-reclamation plant (WRP) effluents that contain mixtures of natural and anthropogenic chemicals that persist through the treatment processes. In effluent-impacted streams, aquatic organisms such as fish are continuously exposed to biologically-active chemicals throughout their life cycles. The North Shore Channel of the Chicago River (Chicago, Illinois) is part of an urban ecosystem in which > 80% of the annual flow consists of effluent from the North Side WRP. In this study, multiple samplings of the effluent and stream water were conducted and fish (largemouth bass and carp) were collected on 2 occasions from the North Shore Channel. Fish also were collected once from the Outer Chicago Harbor in Lake Michigan, a reference site not impacted by WRP discharges. Over 100 organic chemicals with differing behaviors and biological effects were measured, and 23 compounds were detected in all of the water samples analyzed. The most frequently detected and highest concentration (> 100 ??g/L) compounds were ethylenediaminetetraacetic acid and 4-nonylphenolmono-to-tetraethoxycarboxylic acids. Other biologically-active chemicals including bisphenol A, 4-nonylphenol, 4-nonylphenolmono-to-tetraethoxylates, 4- tert-octylphenol, and 4- tert-octylphenolmono-to-tetraethoxylates were detected at lower concentrations (< 5 ??g/L). The biogenic steroidal hormones 17??-estradiol, estrone, testosterone, 4-androstene-3,17-dione, and cis-androsterone were detected at even lower concentrations (< 0.005 ??g/L). There were slight differences in concentrations between the North Side WRP effluent and the North Shore Channel, indicating minimal in-stream attenuation. Fish populations are continuously exposed to mixtures of biologically-active chemicals because of the relative persistency of the chemicals with respect to stream hydraulic residence time, and the lack of a fresh water source for dilution. The majority of male fish exhibited vitellogenin induction, a physiological response consistent with exposure to estrogenic compounds. Tissue-level signs of reproductive disruption, such as ovatestis, were not observed. ?? 2011.

Increased blood levels of persistent organic pollutants (POP) in obese individuals after weight loss-A review.

PubMed

Jansen, Aina; Lyche, Jan L; Polder, Anuschka; Aaseth, Jan; Skaug, Marit Aralt

2017-01-01

Lipophilic persistent organic pollutants (POP) are stored in adipose tissue. Following rapid weight loss such as when induced by bariatric surgery, an increased release of potential harmful lipophilic compounds into the blood circulation may occur. Weight reduction is recommended for overweight and obese individuals in order to decrease risk of weight-related health problems. However, in cases of significant weight reduction POP become mobilized chemicals and consequently may adversely affect health, including endocrine disruption. The objective of the present investigation was to estimate quantitatively the level of mobilization of POP following weight loss over time. According to literature search criteria, 17 studies were identified with 2061 participants. Data from 5 of the studies with 270 participants were used to assess the change in blood levels of POP in percent per kilogram weight loss. Weight loss in the included studies varied from 4.4 to 64.8 kg. In all studies, the majority of POP concentrations in blood were found to rise following weight reduction. Blood concentrations following weight reduction were elevated by 2-4% per kilogram weight loss for most POP examined. The increased POP levels were still elevated 12 mo after intervention. Most research in this field, including animal studies, is carried out on a single compound or group of selected compounds, not taking the "cocktail effect" into consideration. This does not reflect the true range of POP to which humans are actually exposed. Few chronic investigations have been published and, in particular, few studies were available that compared the increase in POP concentrations with clinical consequences as individuals lost weight. These limitations call for caution in interpreting results. The benefits of losing weight still far outweigh the potential adverse health risks. However, further studies are recommended to determine the clinical significance of increased blood levels of POPs following rapid and excessive weight loss, particularly for women attending weight reduction treatment before pregnancy.

Deep-ocean foraging northern elephant seals bioaccumulate persistent organic pollutants.

PubMed

Peterson, Sarah H; Peterson, Michael G; Debier, Cathy; Covaci, Adrian; Dirtu, Alin C; Malarvannan, Govindan; Crocker, Daniel E; Schwarz, Lisa K; Costa, Daniel P

2015-11-15

As top predators in the northeast Pacific Ocean, northern elephant seals (Mirounga angustirostris) are vulnerable to bioaccumulation of persistent organic pollutants (POPs). Our study examined a suite of POPs in blubber (inner and outer) and blood (serum) of free-ranging northern elephant seals. For adult females (N=24), we satellite tracked and sampled the same seals before and after their approximately seven month long foraging trip. For males, we sampled different adults and sub-adults before (N=14) and after (N=15) the same foraging trip. For females, we calculated blubber burdens for all compounds. The highest POP concentrations in males and females were found for ∑DDTs and ∑PCBs. In blubber and serum, males had significantly greater concentrations than females for almost all compounds. For males and females, ∑DDT and ∑PBDEs were highly correlated in blubber and serum. While ∑PCBs were highly correlated with ∑DDTs and ∑PBDEs in blubber and serum for males, ∑PCBs showed weaker correlations with both compounds in females. As females gained mass while foraging, concentrations of nearly all POPs in inner and outer blubber significantly decreased; however, the absolute burden in blubber significantly increased, indicating ingestion of contaminants while foraging. Additionally, we identified three clusters of seal foraging behavior, based on geography, diving behavior, and stable carbon and nitrogen isotopes, which corresponded with differences in ∑DDTs, ∑PBDEs, MeO-BDE 47, as well as the ratio of ∑DDTs to ∑PCBs, indicating the potential for behavior to heighten or mitigate contaminant exposure. The greatest concentrations of ∑DDTs and ∑PBDEs were observed in the cluster that foraged closer to the coast and had blood samples more enriched in (13)C. Bioaccumulation of POPs by elephant seals supports mesopelagic food webs as a sink for POPs and highlights elephant seals as a potential sentinel of contamination in deep ocean food webs. Copyright © 2015 Elsevier B.V. All rights reserved.

A comparative study of coagulation, granular- and powdered-activated carbon for the removal of perfluorooctane sulfonate and perfluorooctanoate in drinking water treatment.

PubMed

Pramanik, Biplob Kumar; Pramanik, Sagor Kumar; Suja, Fatihah

2015-01-01

Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are persistent organic pollutants in the environment and their occurrence causes toxicological effects on humans. We examined different conventional coagulant treatments such as alum, ferric chloride and polyaluminium chloride in removing these compounds. These were then compared with a natural coagulant (Moringa oleifera). We also investigated the powdered-activated carbon (PAC) and granular-activated carbon (GAC) for removing these compounds. At an initial dose of 5 mg/L, polyaluminium chloride led to a higher reduction of PFOS/PFOA compared with alum which in turn was higher than ferric. The removal efficiency increased with the increase in coagulant dose and decrease in pH. M. oleifera was very effective in reducing PFOS and PFOA than conventional coagulants, with a reduction efficiencies of 65% and 72%, respectively, at a dose of 30 mg/L. Both PAC and GAC were very effective in reducing these compounds than coagulations. PAC led to a higher reduction in PFOS and PFOA than GAC due to its greater surface area and shorter internal diffusion distances. The addition of PAC (10 min contact time) with coagulation (at 5 mg/L dosage) significantly increased the removal efficiency, and the maximum removal efficiency was for M. oleifera with 98% and 94% for PFOS and PFOA, respectively. The reduction efficiency of PFOS/PFOA was reduced with the increase in dissolved organic concentration due to the adsorption competition between organic molecules and PFOS/PFOA.

Modulation of oxidative damage by nitroxide free radicals.

PubMed

Dragutan, Ileana; Mehlhorn, Rolf J

2007-03-01

Piperidine nitroxides like 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) are persistent free radicals in non-acidic aqueous solutions and organic solvents that may have value as therapeutic agents in medicine. In biological environments, they undergo mostly reduction to stable hydroxylamines but can also undergo oxidation to reactive oxoammonium compounds. Reactions of the oxoammonium derivatives could have adverse consequences including chemical modification of vital macromolecules and deleterious effects on cell signaling. An examination of their reactivity in aqueous solution has shown that oxoammonium compounds can oxidize almost any organic as well as many inorganic molecules found in biological systems. Many of these reactions appear to be one-electron transfers that reduce the oxoammonium to the corresponding nitroxide species, in contrast to a prevalence of two-electron reductions of oxoammonium in organic solvents. Amino acids, alcohols, aldehydes, phospholipids, hydrogen peroxide, other nitroxides, hydroxylamines, phenols and certain transition metal ions and their complexes are among reductants of oxoammonium, causing conversion of this species to the paramagnetic nitroxide. On the other hand, thiols and oxoammonium yield products that cannot be detected by ESR even under conditions that would oxidize hydroxylamines to nitroxides. These products may include hindered secondary amines, sulfoxamides and sulfonamides. Thiol oxidation products other than disulfides cannot be restored to thiols by common enzymatic reduction pathways. Such products may also play a role in cell signaling events related to oxidative stress. Adverse consequences of the reactions of oxoammonium compounds may partially offset the putative beneficial effects of nitroxides in some therapeutic settings.

Intrinsic Chemiluminescence Generation during Advanced Oxidation of Persistent Halogenated Aromatic Carcinogens.

PubMed

Mao, Li; Liu, Yu-Xiang; Huang, Chun-Hua; Gao, Hui-Ying; Kalyanaraman, Balaraman; Zhu, Ben-Zhan

2015-07-07

The ubiquitous distribution coupled with their carcinogenicity has raised public concerns on the potential risks to both human health and the ecosystem posed by the halogenated aromatic compounds (XAr). Recently, advanced oxidation processes (AOPs) have been increasingly favored as an "environmentally-green" technology for the remediation of such recalcitrant and highly toxic XAr. Here, we show that AOPs-mediated degradation of the priority pollutant pentachlorophenol and all other XAr produces an intrinsic chemiluminescence that directly depends on the generation of the extremely reactive hydroxyl radicals. We propose that the hydroxyl radical-dependent formation of quinoid intermediates and electronically excited carbonyl species is responsible for this unusual chemiluminescence production. A rapid, sensitive, simple, and effective chemiluminescence method was developed to quantify trace amounts of XAr and monitor their real-time degradation kinetics. These findings may have broad biological and environmental implications for future research on this important class of halogenated persistent organic pollutants.

Persistence and changes in bioavailability of dieldrin, DDE and heptachlor epoxide in earthworms over 45 years

USGS Publications Warehouse

Beyer, W. Nelson; Gale, Robert W.

2013-01-01

The finding of dieldrin (88 ng/g), DDE (52 ng/g), and heptachlor epoxide (19 ng/g) in earthworms from experimental plots after a single moderate application (9 kg/ha) 45 years earlier attests to the remarkable persistence of these compounds in soil and their continued uptake by soil organisms. Half-lives (with 95 % confidence intervals) in earthworms, estimated from exponential decay equations, were as follows: dieldrin 4.9 (4.3-5.7) years, DDE 5.3 (4.7-6.1) years, and heptachlor epoxide 4.3 (3.8-4.9) years. These half-lives were not significantly different from those estimated after 20 years. Concentration factors (dry weight earthworm tissue/dry weight soil) were initially high and decreased mainly during the first 11 years after application. By the end of the study, average concentration factors were 1.5 (dieldrin), 4.0 (DDE), and 1.8 (heptachlor epoxide), respectively.

Biota and Biomolecules in Extreme Environments on Earth: Implications for Life Detection on Mars

PubMed Central

Aerts, Joost W.; Röling, Wilfred F.M.; Elsaesser, Andreas; Ehrenfreund, Pascale

2014-01-01

The three main requirements for life as we know it are the presence of organic compounds, liquid water, and free energy. Several groups of organic compounds (e.g., amino acids, nucleobases, lipids) occur in all life forms on Earth and are used as diagnostic molecules, i.e., biomarkers, for the characterization of extant or extinct life. Due to their indispensability for life on Earth, these biomarkers are also prime targets in the search for life on Mars. Biomarkers degrade over time; in situ environmental conditions influence the preservation of those molecules. Nonetheless, upon shielding (e.g., by mineral surfaces), particular biomarkers can persist for billions of years, making them of vital importance in answering questions about the origins and limits of life on early Earth and Mars. The search for organic material and biosignatures on Mars is particularly challenging due to the hostile environment and its effect on organic compounds near the surface. In support of life detection on Mars, it is crucial to investigate analogue environments on Earth that resemble best past and present Mars conditions. Terrestrial extreme environments offer a rich source of information allowing us to determine how extreme conditions affect life and molecules associated with it. Extremophilic organisms have adapted to the most stunning conditions on Earth in environments with often unique geological and chemical features. One challenge in detecting biomarkers is to optimize extraction, since organic molecules can be low in abundance and can strongly adsorb to mineral surfaces. Methods and analytical tools in the field of life science are continuously improving. Amplification methods are very useful for the detection of low concentrations of genomic material but most other organic molecules are not prone to amplification methods. Therefore, a great deal depends on the extraction efficiency. The questions “what to look for”, “where to look”, and “how to look for it” require more of our attention to ensure the success of future life detection missions on Mars. PMID:25370528

Biota and biomolecules in extreme environments on Earth: implications for life detection on Mars.

PubMed

Aerts, Joost W; Röling, Wilfred F M; Elsaesser, Andreas; Ehrenfreund, Pascale

2014-10-13

The three main requirements for life as we know it are the presence of organic compounds, liquid water, and free energy. Several groups of organic compounds (e.g., amino acids, nucleobases, lipids) occur in all life forms on Earth and are used as diagnostic molecules, i.e., biomarkers, for the characterization of extant or extinct life. Due to their indispensability for life on Earth, these biomarkers are also prime targets in the search for life on Mars. Biomarkers degrade over time; in situ environmental conditions influence the preservation of those molecules. Nonetheless, upon shielding (e.g., by mineral surfaces), particular biomarkers can persist for billions of years, making them of vital importance in answering questions about the origins and limits of life on early Earth and Mars. The search for organic material and biosignatures on Mars is particularly challenging due to the hostile environment and its effect on organic compounds near the surface. In support of life detection on Mars, it is crucial to investigate analogue environments on Earth that resemble best past and present Mars conditions. Terrestrial extreme environments offer a rich source of information allowing us to determine how extreme conditions affect life and molecules associated with it. Extremophilic organisms have adapted to the most stunning conditions on Earth in environments with often unique geological and chemical features. One challenge in detecting biomarkers is to optimize extraction, since organic molecules can be low in abundance and can strongly adsorb to mineral surfaces. Methods and analytical tools in the field of life science are continuously improving. Amplification methods are very useful for the detection of low concentrations of genomic material but most other organic molecules are not prone to amplification methods. Therefore, a great deal depends on the extraction efficiency. The questions "what to look for", "where to look", and "how to look for it" require more of our attention to ensure the success of future life detection missions on Mars.

Persistent Luminescence in Non-Eu2+-Doped Compounds: A Review

PubMed Central

Van den Eeckhout, Koen; Poelman, Dirk; Smet, Philippe F.

2013-01-01

During the past few decades, the research on persistent luminescent materials has focused mainly on Eu2+-doped compounds. However, the yearly number of publications on non-Eu2+-based materials has also increased steadily. By now, the number of known persistent phosphors has increased to over 200, of which over 80% are not based on Eu2+, but rather, on intrinsic host defects, transition metals (manganese, chromium, copper, etc.) or trivalent rare earths (cerium, terbium, dysprosium, etc.). In this review, we present an overview of these non-Eu2+-based persistent luminescent materials and their afterglow properties. We also take a closer look at some remaining challenges, such as the excitability with visible light and the possibility of energy transfer between multiple luminescent centers. Finally, we summarize the necessary elements for a complete description of a persistent luminescent material, in order to allow a more objective comparison of these phosphors. PMID:28811409

Isolation and Identification of Persistent Chlorinated Organophosphorus Flame Retardant-Degrading Bacteria ▿

PubMed Central

Takahashi, Shouji; Satake, Ikuko; Konuma, Isao; Kawashima, Koji; Kawasaki, Manami; Mori, Shingo; Morino, Jun; Mori, Junichi; Xu, Hongde; Abe, Katsumasa; Yamada, Ryo-hei; Kera, Yoshio

2010-01-01

Tris(2-chloroethyl) and tris(1,3-dichloro-2-propyl) phosphates are chlorinated persistent flame retardants that have recently emerged as environmental pollutants. Two bacterial strains that can degrade the compounds when they are the sole phosphorus sources have been isolated and identified as members of the sphingomonads. The strains can be useful for the bioremediation of environments contaminated with these compounds. PMID:20525857

Characterization and Transcriptome Analysis of Acinetobacter baumannii Persister Cells.

PubMed

Alkasir, Rashad; Ma, Yanan; Liu, Fei; Li, Jing; Lv, Na; Xue, Yong; Hu, Yongfei; Zhu, Baoli

2018-06-14

Acinetobacter baumannii is a nonfermenting Gram-negative bacillus. A. baumannii resistance is a significant obstacle to clinical infection treatment. The existence of persister cells (persisters) might represent the reason for therapy failure and relapse, and such cells may be the driving force behind rising resistance rates. In this study, A. baumannii ATCC 19606 was used as a target to explore the essential features of A. baumannii persisters. Antibiotic treatment of A. baumannii cultures at 50-fold the minimum inhibitory concentration resulted in a distinct plateau of surviving drug-tolerant persisters. The sensitive bacteria were lysed with ceftazidime, and the nonreplicating bacteria were isolated for transcriptome analysis using RNA sequencing. We analyzed the transcriptome of A. baumannii persisters and identified significantly differentially expressed genes, as well as their enriched pathways. The results showed that both the GP49 (HigB)/Cro (HigA) and DUF1044/RelB toxin/antitoxin systems were significantly increased during the persister incubation period. In addition, the activities of certain metabolic pathways (such as electron transport, adenosine triphosphate [ATP], and the citrate cycle) decreased sharply after antibiotic treatment and remained low during the persister period, while aromatic compound degradation genes were only upregulated in persisters. These results suggest the involvement of aromatic compound degradation genes in persister formation and maintenance. They further provide the first insight into the mechanism of persister formation in A. baumannii.

A persistent organic pollutant related with unusual high frequency of hermaphroditism in the neotropical anuran Physalaemus cuvieri Fitzinger, 1826.

PubMed

Moresco, Rafaela M; Margarido, Vladimir P; de Oliveira, Classius

2014-07-01

Representing a reflection of anthropic activity, the level of xenobiotic compounds in aquatic ecosystems has increased in recent years, bringing severe damage to the environment. The present work reports the occurrence of malformation in gonads of Physalaemus cuvieri individuals from a population of Atlantic Forest in Southern Brazil. Twenty male specimens were collected, which had their testicles removed, immersed in Karnovsky fixative solution, included in historesin for 2 μm cuts and stained with Hematoxylin-eosin. Four specimens showed intersexual gonads condition along with the presence of sperm and oocytes. In order to test a possible contamination of water, 2L were collected from the water body to check organochlorine, organophosphate and carbamate compounds. The analysis of water showed the presence of agrotoxic Dieldrin in a concentration of 0.05 μg/L, representing a concentration above the recommended reference. This agrotoxic, in addition to acting as endocrine disrupter and commercially prohibited, has quite persistent residual effects, and may be responsible for the high frequency of P. cuvieri with intersexual gonads, which in the long term can represent a risk for this population due to the potential impact on its effective reproductive ability. Copyright © 2014 Elsevier Inc. All rights reserved.

Ecotoxicological risk assessment of environmental pollutants in the Arctic.

PubMed

Brunström, B; Halldin, K

2000-03-15

Concentrations of such persistent organic pollutants (POPs) as polychlorinated biphenyls (PCBs) are high in certain Arctic animal species. The polar bear, Arctic fox, and glaucous gull may be exposed to PCB levels above lowest-observed-adverse-effect-level (LOAEL) values for adverse effects on reproduction in mammals and birds. However, the dioxin-like congeners seem to be major contributors to the reproductive effects of PCBs and the relative concentrations of these congeners are low in polar bears. Temporal trends for POPs in Arctic wildlife and the sensitivities of Arctic species to these compounds determine the risk for future adverse health effects.

Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis.

PubMed

Pflieger, Marilyne; Makorič, Petra; Kovač Viršek, Manca; Koren, Špela

2017-07-01

Plastic resin pellets, categorized as microplastics (≤5 mm in diameter), are small granules that can be unintentionally released to the environment during manufacturing and transport. Because of their environmental persistence, they are widely distributed in the oceans and on beaches all over the world. They can act as a vector of potentially toxic organic compounds (e.g., polychlorinated biphenyls) and might consequently negatively affect marine organisms. Their possible impacts along the food chain are not yet well understood. In order to assess the hazards associated with the occurrence of plastic pellets in the marine environment, it is necessary to develop methodologies that allow for rapid determination of associated organic contaminant levels. The present protocol describes the different steps required for sampling resin pellets, analyzing adsorbed organochlorine pesticides (OCPs) and identifying the plastic type. The focus is on the extraction of OCPs from plastic pellets by means of a pressurized fluid extractor (PFE) and on the polymer chemical analysis applying Fourier Transform-InfraRed (FT-IR) spectroscopy. The developed methodology focuses on 11 OCPs and related compounds, including dichlorodiphenyltrichloroethane (DDT) and its two main metabolites, lindane and two production isomers, as well as the two biologically active isomers of technical endosulfan. This protocol constitutes a simple and rapid alternative to existing methodology for evaluating the concentration of organic contaminants adsorbed on plastic pieces.

Biomimicry of volatile-based microbial control for managing emerging fungal pathogens.

PubMed

Gabriel, K T; Joseph Sexton, D; Cornelison, C T

2018-05-01

Volatile organic compounds (VOCs) are known to be produced by a wide range of micro-organisms and for a number of purposes. Volatile-based microbial inhibition in environments such as soil is well-founded, with numerous antimicrobial VOCs having been identified. Inhibitory VOCs are of interest as microbial control agents, as low concentrations of gaseous VOCs can elicit significant antimicrobial effects. Volatile organic compounds are organic chemicals typically characterized as having low molecular weight, low solubility in water, and high vapour pressure. Consequently, VOCs readily evaporate to the gaseous phase at standard temperature and pressure. This contact-independent antagonism presents unique advantages over traditional, contact-dependent microbial control methods, including increased surface exposure and reduced environmental persistence. This approach has been the focus of our recent research, with positive results suggesting it may be particularly promising for the management of emerging fungal pathogens, such as the causative agents of white-nose syndrome of bats and snake fungal disease, which are difficult or impossible to treat using traditional approaches. Here, we review the history of volatile-based microbial control, discuss recent progress in formulations that mimic naturally antagonistic VOCs, outline the development of a novel treatment device, and highlight areas where further work is needed to successfully deploy VOCs against existing and emerging fungal pathogens. © 2017 The Society for Applied Microbiology.

Analysis of Volatile Organic and Sulfur Compounds in Air Near a Pulp Paper Mill in North-Central Idaho

NASA Astrophysics Data System (ADS)

Johnston, N. A. C.; Bundy, B. A.; Andrew, J. P.; Grimm, B. K.; Ketcherside, D.; Rivero-Zevallos, J. A.; Uhlorn, R. P.

2017-12-01

Lewiston, Idaho is a small city in the Snake River Valley bordering North-Central Idaho and Southeastern Washington, with a population of over 40,000 including the surrounding areas. One of the main industries and employers in the region is a kraft paper mill in North Lewiston, which results in odorous levels of sulfur air pollutants there. The Idaho Department of Environmental Quality has an air monitoring station in Lewiston but measures only air particulate matter (PM). Surprisingly, not much long-term data exists on this area for specific air constituents such as volatile organics, hazardous air pollutants, and sulfur compounds. One year-long study conducted in 2006-2007 by the Nez Perce Tribe found high formaldehyde levels in the area, and warranted further study in July of 2016-2017. Our ongoing study began in the fall of 2016 and investigates the seasonal air composition in the Lewiston area. Specifically, active air sampling via sorbent tubes and analysis by thermal desorption gas chromatography-mass spectrometry (TD-GC-MS). was utilized to measure over 50 volatile organic compounds, hazardous air pollutants, and sulfurous compounds in ambient air (adapted from EPA Method TO-17). Seasonal, diurnal, and spatial variations in air composition were explored with weekly to monthly grab sampling. Dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) were the primary sulfur compounds detected, and these varied considerably depending on time of day, season, location and meteorology. DMS was more prevalent in the summer months, while DMDS was more prevalent in the spring. Elevated concentrations of benzene and chloroform were found in the region during 2017, with average values of short term grab samples over three times the acceptable ambient concentrations in Idaho. These levels did not persist during longer term sampling of 12-hours, however further monitoring is needed to assess a potential health concern.

Organic Chemostratigraphic Markers Characteristic of the (Informally Designated) Anthropocene Epoch

NASA Astrophysics Data System (ADS)

Kruge, M. A.

2008-12-01

Recognizing the tremendous collective impact of humans on the environment in the industrial age, the proposed designation of the current time period as the Anthropocene Epoch has considerable merit. One of the signature activities during this time continues to be the intensive extraction, processing, and combustion of fossil fuels. While fossil fuels themselves are naturally-occurring, they are most often millions of years old and associated with deeply buried strata. They may be found at the surface, for example, as natural oil seeps or coal seam outcrops, but these are relatively rare occurrences. Fossil fuels and their myriad by- products become the source of distinctive organic chemostratigraphic marker compounds for the Anthropocene when they occur out of their original geological context, i.e., as widespread contaminants in sediments and soils. These persistent compounds have high long-term preservation potential, particularly when deposited under low oxygen conditions. Fossil fuels can occur as environmental contaminants in raw form (e.g., crude petroleum spilled during transport) or as manufactured products (e.g., diesel oil from a leaking storage facility, coal tar from a manufactured gas plant, plastic waste in a landfill, pesticides from petroleum feedstock in agricultural soils). Distinctive assemblages of hydrocarbon marker compounds including acyclic isoprenoids, hopanes, and steranes can be readily detected by gas chromatography/mass spectrometric analysis of surface sediments and soils. Polycyclic aromatic hydrocarbons (PAHs), along with sulfur-, oxygen-, and nitrogen-containing aromatic compounds, are also characteristic of fossil fuels and are readily detectable as well. More widespread is the airfall deposition of fossil fuel combustion products from vehicular, domestic and industrial sources. These occur in higher concentrations in large urban centers, but are also detected in remote areas. Parent (nonmethylated) PAHs such as phenanthrene, fluoranthene and pyrene are the most abundant organic marker compounds in these combustion-derived deposits, distinguishable in their types and proportions from the combustion products of natural vegetation fires. The occurrence of specific fossil fuel combustion-derived PAH assemblages serves as a stratigraphic signature for Anthropocene deposits.

Characterization of organochlorine pesticides, brominated flame retardants and dioxin-like compounds in shellfish and eel from Fiji.

PubMed

Lal, Vincent; Bridgen, Phil; Votadroka, Waisea; Raju, Rupantri; Aalbersberg, William

2014-09-01

This article gives an overview of a range of persistent organic pollutant chemical levels in shellfish (Batissa violacea and Anadara antiquata) species and eel (Gymnothorax flavimarginatus) from Fiji. As there is limited data in published literature to date, this paper reports first data on a range of persistent organic pollutants and highlights the more prominent POP chemicals present in marine biota in Fiji. A significant number of POP chemicals were detected (e.g. 17 PCDD/PCDF, 12dl-PCBs, organochlorine pesticides and brominated flame retardants), the concentrations found were generally low (e.g. parts per billion level). The low levels of contamination are indicative of a low input from long range and short-range transport as well as few local point sources. Also concentrations of POPs in eel and shellfish from Fiji are low in comparison to wild species in other regions and are within acceptable limits for POP chemicals in fish and fishery products set by the European Union. It describes also results of early studies on basic POPs levels in shellfish in several Pacific Island Countries, which generally show relatively low levels. Copyright © 2014 Elsevier B.V. All rights reserved.

Formation of Polychlorinated Biphenyls on Secondary Copper Production Fly Ash: Mechanistic Aspects and Correlation to Other Persistent Organic Pollutants

NASA Astrophysics Data System (ADS)

Jiang, Xiaoxu; Liu, Guorui; Wang, Mei; Zheng, Minghui

2015-09-01

Emission of unintentionally formed polychlorinated biphenyls (PCBs) from industrial thermal processes is a global issue. Because the production and use of technical PCB mixtures has been banned, industrial thermal processes have become increasingly important sources of PCBs. Among these processes, secondary copper smelting is an important PCB source in China. In the present study, the potential for fly ash-mediated formation of PCBs in the secondary copper industry, and the mechanisms involved, were studied in laboratory thermochemical experiments. The total PCB concentrations were 37-70 times higher than the initial concentrations. Thermochemical reactions on the fly ash amplified the potential toxic equivalents of PCBs. The formation of PCBs over time and the effect of temperature were investigated. Based on analyses of PCB homologue profiles with different reaction conditions, a chlorination mechanism was proposed for forming PCBs in addition to a de novo synthesis mechanism. The chlorination pathway was supported by close correlations between each pair of adjacent homologue groups. Formation of PCBs and multiple persistent organic pollutants, including polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated naphthalenes, occurred during the tests, indicating that these compounds may share similar formation mechanisms.

Novel sorbents for environmental remediation

NASA Astrophysics Data System (ADS)

Manariotis, Ioannis D.; Karapanagioti, Hrissi K.; Werner, David

2014-05-01

Nowadays, one of the major environmental problems is the pollution of aquatic systems and soil by persistent pollutants. Persistent pollutants have been found widespread in sediments, surface waters, and drinking water supplies. The removal of pollutants can be accomplished prior to their discharge to receiving bodies or by immobilizing them onto soil. Sorption is the most commonly applied process, and activated carbons have been widely used. Rapid progress in nanotechnology and a new focus on biomass-based instead of non-renewable starting materials have produced a wide range of novel engineered sorbents including biosorbents, biochars, carbon-based nanoparticles, bio-nano hybrid materials, and iron-impregnated activated carbons. Sorbent materials have been used in environmental remediation processes and especially in agricultural soil, sediments and contaminated soil, water treatment, and industrial wastewater treatment. Furthermore, sorbents may enhance the synergistic action of other processes, such as volatilization and biodegradation. Novel sorbents have been employed for the removal or immobilization of persistent pollutants such as and include heavy metals (As, Cr, Cu, Pb, Cd, and Hg), halogenated organic compounds, endocrine disrupting chemicals, metalloids and non-metallic elements, and other organic pollutants. The development and evaluation of novel sorbents requires a multidisciplinary approach encompassing environmental, nanotechnology, physical, analytical, and surface chemistry. The necessary evaluations encompass not only the efficiency of these materials to remove pollutants from surface waters and groundwater, industrial wastewater, polluted soils and sediments, etc., but also the potential side-effects of their environmental applications. The aim of this work is to present the results of the use of biochar and impregnated carbon sorbents for the removal of organic pollutants and metals. Furthermore, the new findings from the forthcoming session on Novel sorbents for environmental remediation, will also be evaluated and presented.

Laboratory persistence in soil of thiacloprid, pendimethalin and fenarimol incubated with treated wastewater and dissolved organic matter solutions. Contribution of soil biota.

PubMed

Rodríguez-Liébana, José Antonio; ElGouzi, Siham; Peña, Aránzazu

2017-08-01

Reutilization of treated wastewater (TWW) in agriculture has continued to grow, especially in areas prone to frequent drought periods. One of the major aspects derived from this practice is the addition of important amounts of organic carbon (OC) that could interfere with the fate of organic contaminants in soils. This study has evaluated the impact of irrigation with a secondary TWW and dissolved OC (DOC) solutions from sewage sludge in the dissipation of thiacloprid (THC), pendimethalin (PDM) and fenarimol (FEN) in an OC-poor agricultural soil under laboratory conditions. The effect on soil microbial activity was also assessed through the measurement of dehydrogenase activity. Biotic processes were the main responsible for the degradation of the three compounds. Results showed that while THC was rapidly degraded (DT 50  ≤ 5.5 d), PDM and FEN were moderately persistent in soil (DT 50  ≥ 93 d). Incubation with TWW did not modify the decay rate of the three pesticides, but initially inhibited soil biota. Solutions of DOC did not alter the dissipation of FEN, but contrasting effects were observed for THC and PDM. Low DOC concentrations (30 mg L -1 ) accelerated THC disappearance, a fact explained by stimulation of endogenous biota rather than by the presence of exogenous microorganisms from the solution. On the other hand, high DOC concentrations (300 mg L -1 ) had more influence on the activity of microorganisms at longer times, and showed a trend to enhance the disappearance of the moderately persistent PDM. Copyright © 2017 Elsevier Ltd. All rights reserved.

Volatile organic compound emissions from green waste composting: Characterization and ozone formation

NASA Astrophysics Data System (ADS)

Kumar, Anuj; Alaimo, Christopher P.; Horowitz, Robert; Mitloehner, Frank M.; Kleeman, Michael J.; Green, Peter G.

2011-04-01

Composting of green waste separated from the disposed solid waste stream reduces biodegradable inputs into landfills, and contributes valuable soil amendments to agriculture. Agencies in regions with severe air quality challenges, such as California's San Joaquin Valley (SJV), have raised concerns about gases emitted during the composting process, which are suspected to contribute to persistent high levels of ground-level ozone formation. The goal of the current study is to thoroughly characterize volatile organic compound (VOC) emissions from green waste compost piles of different ages (fresh tipped piles, 3-6 day old windrows, and 2-3 week old windrows). Multiple sampling and analytical approaches were applied to ensure the detection of most gaseous organic components emitted. More than 100 VOCs were detected and quantified in this study, including aliphatic alkanes, alkenes, aromatic hydrocarbons, biogenic organics, aldehydes, ketones, alcohols, furans, acids, esters, ether, halogenated hydrocarbons and dimethyl disulfide (DMDS). Alcohols were found to be the dominating VOC in the emissions from a compost pile regardless of age, with fluxes ranging from 2.6 to 13.0 mg m -2 min -1 with the highest emissions coming from the younger composting windrows (3-6 days). Average VOC emissions other than alcohols were determined to be 2.3 mg m -2 min -1 from younger windows, which was roughly two times higher than either the fresh tipping pile (1.2 mg m -2 min -1) or the older windrows (1.4 mg m -2 min -1). It was also observed that the older windrows emit a slightly larger proportion of more reactive compounds. Approximately 90% of the total VOCs were found to have maximum incremental reactivity of less than 2. Net ozone formation potential of the emissions was also assessed.

Matrix effects on organic pollutants analysis in marine sediment

NASA Astrophysics Data System (ADS)

Azis, M. Y.; Asia, L.; Piram, A.; Buchari, B.; Doumenq, P.; Setiyanto, H.

2018-05-01

Interference from the matrix sample can influence of the accurate analytical method. Accelerated Solvent Extraction and their purification methods were tried to separate the organic micropollutants respectively in marine sediment. Those matrix were as organic pollutants evaluation in marine environment. Polychlorinated Biphenyls (PCBs) and Organochlorine pesticides (OCPs) are two examples organic pollutant in environment which are carcinogenic and mutagenic. Marine sediments are important matrices of information regarding the human activities in coastal areas as well as the fate and behavior of organic pollutants, which are persistent in long-term. This research purpose to evaluate the matrice effect and the recovery from marine sediment spiking with several standar solution and deuterium of molecular target from organic pollutants in not polluted sample of sediment. Matrice samples was tested from indicate in unpolluted location. The methods were evaluated with standard calibration curve (linearity < 0.999, LOQ various ranged 0.5-1000 pg.μL-1 and LOD > LOQ). Recovery (YE) relative, Matrice Effect (ME) relative correction with deuteriated standar were evaluated the interference the matrix. Interference effect for OCPs compounds were higher than PCBs in marine sediment.

Enantioselective Biotransformation of Chiral Persistent Organic Pollutants.

PubMed

Zhang, Ying; Ye, Jing; Liu, Min

2017-01-01

Enantiomers of chiral compounds commonly undergo enantioselective transformation in most biologically mediated processes. As chiral persistent organic pollutants (POPs) are extensively distributed in the environment, differences between enantiomers in biotransformation should be carefully considered to obtain exact enrichment and specific health risks. This review provides an overview of in vivo biotransformation of chiral POPs currently indicated in the Stockholm Convention and their chiral metabolites. Peer-reviewed journal articles focused on the research question were thoroughly searched. A set of inclusion and exclusion criteria were developed to identify relevant studies. We mainly compared the results from different animal models under controlled laboratory conditions to show the difference between enantiomers in terms of distinct transformation potential. Interactions with enzymes involved in enantioselective biotransformation, especially cytochrome P450 (CYP), were discussed. Further research areas regarding this issue were proposed. Limited evidence for a few POPs has been found in 30 studies. Enantioselective biotransformation of α-hexachlorocyclohexane (α-HCH), chlordane, dichlorodiphenyltrichloroethane (DDT), heptachlor, hexabromocyclododecane (HBCD), polychlorinated biphenyls (PCBs), and toxaphene, has been investigated using laboratory mammal, fish, bird, and worm models. Tissue and excreta distributions, as well as bioaccumulation and elimination kinetics after administration of racemate and pure enantiomers, have been analyzed in these studies. Changes in enantiomeric fractions have been considered as an indicator of enantioselective biotransformation of chiral POPs in most studies. Results of different laboratory animal models revealed that chiral POP biotransformation is seriously affected by chirality. Pronounced results of species-, tissue-, gender-, and individual-dependent differences are observed in in vivo biotransformation of chiral POPs. Enantioselective biotransformation of chiral POPs is dependent on enzyme amounts and activities. However, the role of cytochrome P450 in enantioselective biotransformation has not yet been confirmed. Currently available data on biotransformation of chiral POPs provide a preliminary understanding of the fate of chiral compounds in organisms. Further detailed studies of species-dependent biotransformation pathway and molecular mechanism in various animal models should be performed to comprehensively understand chiral POP biotransformation.

Evidence for major input of riverine organic matter into the ocean

USGS Publications Warehouse

Cao, Xiaoyan; Aiken, George R.; Butler, Kenna D.; Huntington, Thomas G.; Balch, William M.; Mao, Jingdong; Schmidt-Rohr, Klaus

2018-01-01

The changes in the structure of XAD-8 isolated dissolved organic matter (DOM) samples along a river (Penobscot River) to estuary (Penobscot Bay) to ocean (across the Gulf of Maine) transect and from the Pacific Ocean were investigated using selective and two dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy coupled with elemental and carbon isotope analysis. The results provide important insights into the nature of relatively stable structures in the river-to-ocean continuum and the enigma of the fate of terrestrial DOM in the marine system. First, lignin and carboxyl-rich alicyclic molecules (CRAMs), which are indistinguishable from mass spectrometry, were clearly differentiated with NMR spectroscopy. NMR unambiguously showed that CRAMs persisted along the river-to-ocean transect and in the Pacific Ocean, while lignin residues dramatically decreased in abundance from the river to the coastal ocean and the Pacific Ocean. The results challenge a previous conclusion that lignin-derived compounds are refractory and can accumulate in the coastal ocean. The loss of terrestrial plant-derived aromatic compounds such as lignin and tannin residues throughout the sequence of riverine, coastal, and open ocean DOM extracts could also partially explain the decreasing organic carbon recovery by XAD-8 isolation and the change in carbon stable isotope composition from riverine DOM (δ13C −27.6‰) to ocean DOM (δ13C −23.0‰) extracts. The observation, from advanced NMR, of similar CRAM molecules in XAD-8 isolated DOM samples from the Penobscot River to the Penobscot Bay and from the ocean refutes a previous conclusion that XAD-isolated DOM samples from seawater and river are distinctly different. The alicyclic structural features of CRAMs and their presence as the major structural units in DOM extracts from the Penobscot River to Gulf of Maine transect, together with the deduced old 14C age of CRAMs in the ocean, imply that terrestrial CRAMs may persist on timescales long enough to be transported into the ocean.

Chemometric Methods and Theoretical Molecular Descriptors in Predictive QSAR Modeling of the Environmental Behavior of Organic Pollutants

NASA Astrophysics Data System (ADS)

Gramatica, Paola

This chapter surveys the QSAR modeling approaches (developed by the author's research group) for the validated prediction of environmental properties of organic pollutants. Various chemometric methods, based on different theoretical molecular descriptors, have been applied: explorative techniques (such as PCA for ranking, SOM for similarity analysis), modeling approaches by multiple-linear regression (MLR, in particular OLS), and classification methods (mainly k-NN, CART, CP-ANN). The focus of this review is on the main topics of environmental chemistry and ecotoxicology, related to the physico-chemical properties, the reactivity, and biological activity of chemicals of high environmental concern. Thus, the review deals with atmospheric degradation reactions of VOCs by tropospheric oxidants, persistence and long-range transport of POPs, sorption behavior of pesticides (Koc and leaching), bioconcentration, toxicity (acute aquatic toxicity, mutagenicity of PAHs, estrogen binding activity for endocrine disruptors compounds (EDCs)), and finally persistent bioaccumulative and toxic (PBT) behavior for the screening and prioritization of organic pollutants. Common to all the proposed models is the attention paid to model validation for predictive ability (not only internal, but also external for chemicals not participating in the model development) and checking of the chemical domain of applicability. Adherence to such a policy, requested also by the OECD principles, ensures the production of reliable predicted data, useful also in the new European regulation of chemicals, REACH.

Sorption and bioaccumulation behavior of multi-class hydrophobic organic contaminants in a tropical marine food web.

PubMed

Zhang, Hui; Kelly, Barry C

2018-05-01

While numerous studies have demonstrated the environmental behavior of legacy persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), information regarding sorption and bioaccumulation potential of other widely used organic chemicals such as halogenated flame retardants (HFRs) is limited. This study involved a comprehensive field investigation of multi-class hydrophobic organic contaminants (HOCs) in environmental media and fish in Singapore Strait, an important tropical maritime strait in Southeast Asia. In total, 90 HOCs were analyzed, including HFRs, synthetic musks, PCBs, OCPs, as well as triclosan and methyl triclosan. The results show that the organic carbon normalized sediment-seawater distribution ratios (C SED /C WD ) of the studied compounds are comparable to the organic carbon-water partition coefficients (K OC ), over a log K OC range of approximately 4-11. The observed species-specific bioaccumulation factors (BAFs), biota-sediment accumulation factors (BSAFs), organism-environment media fugacity ratios (f FISH /f WD and f FISH /f SED ) and trophic magnification factors (TMFs) indicate that legacy POPs and PBDE 47 show bioaccumulation behavior in this tropical marine ecosystem, while triclosan, tonalide, dodecachlorodimethanodibenzocyclooctane stereoisomers (DDC-COs), and hexabromocyclododecanes (HBCDDs) do not. Methyl triclosan and galaxolide exhibit moderate biomagnification. Tetrabromobisphenol A (TBBPA) and 1,2-bis (2,4,6-tribromophenoxy)ethane (BTBPE) were detected in environmental media but not in any of the organisms, suggesting low bioaccumulation potential of these flame retardants. The apparently low bioaccumulation potential of the studied HFRs and synthetic musks is likely because of metabolic transformation and/or reduced bioavailability due to the hydrophobic nature of these compounds. Copyright © 2018 Elsevier Ltd. All rights reserved.

A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP)

EPA Science Inventory

The Pilot Study of Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) investigated the aggregate exposures of 257 preschool children and their primary adult caregivers to pollutants commonly detected in their everyday environments. ...

Geographic Differences in Persistent Organic Pollutant Levels of Yellowfin Tuna.

PubMed

Nicklisch, Sascha C T; Bonito, Lindsay T; Sandin, Stuart; Hamdoun, Amro

2017-06-26

Fish are a source of persistent organic pollutants (POPs) in the human diet. Although species, trophic level, and means of production are typically considered in predicting fish pollutant load, and thus recommendations of consumption, capture location is usually not accounted for. Yellowfin tuna ( Thunnus albacares ) are harvested from across the world's oceans and are widely consumed. Here, we determined geographic variation in the overall mass, concentration, and composition of POPs in yellowfin and examined the differences in levels of several POP congeners of potential relevance to human health. We sampled dorsal muscle of 117 yellowfin tuna from 12 locations worldwide, and measured POP levels using combined liquid or gas chromatography and mass spectrometry according to U.S. Environmental Protection Agency standard procedures. POP levels varied significantly among sites, more than 36-fold on a mass basis. Individual fish levels ranged from 0.16 to 138.29 ng/g wet weight and lipid-normalized concentrations from 0.1 to 12.7 μM. Levels of 10 congeners that interfere with the cellular defense protein P-glycoprotein, termed transporter interfering compounds (TICs), ranged from 0.05 to 35.03 ng/g wet weight and from 0.03 to 3.32 μM in tuna lipid. Levels of TICs, and their individual congeners, were strongly associated with the overall POP load. Risk-based analysis of several carcinogenic POPs indicated that the fish with the highest levels of these potentially harmful compounds were clustered at specific geographic locations. Capture location is an important consideration when assessing the level and risk of human exposure to POPs through ingestion of wild fish. https://doi.org/10.1289/EHP518.

Endocrine effects of contaminated sediments on the freshwater snail Potamopyrgus antipodarum in vivo and in the cell bioassays in vitro.

PubMed

Mazurová, E; Hilscherová, K; Jálová, V; Köhler, H-R; Triebskorn, R; Giesy, J P; Bláha, L

2008-09-17

Lake Pilnok located in the black coal-mining region Ostrava-Karvina, Czech Republic, contains sediments highly contaminated with powdered waste coal. Moreover, population of the endangered species of narrow-clawed crayfish Pontastacus leptodactylus with high proportion of intersex individuals (18%) was observed at this site. These findings motivated our work that aimed to evaluate contamination, endocrine disruptive potency using in vitro assays and in vivo effects of contaminated sediments on reproduction of sediment-dwelling invertebrates. Chemical analyses revealed low concentrations of persistent chlorinated compounds and heavy metals but concentrations of polycyclic aromatic hydrocarbons (PAH) were high (sum of 16 PAHs 10 microg/g dw). Organic extracts from sediments caused significant in vitro AhR-mediated activity in the bioassay with H4IIE-luc cells, estrogenicity in MVLN cells and anti-androgenicity in recombinant yeast assay, and these effects could be attributed to non-persistent compounds derived from the waste coal. We have also observed significant in vivo effects of the sediments in laboratory experiments with the Prosobranchian euryhaline mud snail Potamopyrgus antipodarum. Sediments from Lake Pilnok as well as organic extracts of the sediments (externally added to the control sediment) significantly affected fecundity during 8 weeks of exposure. The effects were stimulations of fecundity at lower concentrations at the beginning of the experiment followed by inhibitions of fecundity and general toxicity. Our study indicates presence of chemicals that affected endocrine balance in invertebrates, and emphasizes the need for integrated approaches combining in vitro and in vivo bioassays with identification of chemicals to elucidate ecotoxicogical impacts of contaminated sediment samples.

Low concentrations of persistent organic pollutants (POPs) in air at Cape Verde.

PubMed

Nøst, Therese Haugdahl; Halse, Anne Karine; Schlabach, Martin; Bäcklund, Are; Eckhardt, Sabine; Breivik, Knut

2018-01-15

Ambient air is a core medium for monitoring of persistent organic pollutants (POPs) under the Stockholm Convention and is used in studies of global transports of POPs and their atmospheric sources and source regions. Still, data based on active air sampling remain scarce in many regions. The primary objectives of this study were to (i) monitor concentrations of selected POPs in air outside West Africa, and (ii) to evaluate potential atmospheric processes and source regions affecting measured concentrations. For this purpose, an active high-volume air sampler was installed on the Cape Verde Atmospheric Observatory at Cape Verde outside the coast of West Africa. Sampling commenced in May 2012 and 43 samples (24h sampling) were collected until June 2013. The samples were analyzed for selected polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB) and chlordanes. The concentrations of these POPs at Cape Verde were generally low and comparable to remote sites in the Arctic for several compounds. Seasonal trends varied between compounds and concentrations exhibited strong temperature dependence for chlordanes. Our results indicate net volatilization from the Atlantic Ocean north of Cape Verde as sources of these POPs. Air mass back trajectories demonstrated that air masses measured at Cape Verde were generally transported from the Atlantic Ocean or the North African continent. Overall, the low concentrations in air at Cape Verde were likely explained by absence of major emissions in areas from which the air masses originated combined with depletion during long-range atmospheric transport due to enhanced degradation under tropical conditions (high temperatures and concentrations of hydroxyl radicals). Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Geographic Differences in Persistent Organic Pollutant Levels of Yellowfin Tuna

PubMed Central

Nicklisch, Sascha C.T.; Bonito, Lindsay T.; Sandin, Stuart

2017-01-01

Background: Fish are a source of persistent organic pollutants (POPs) in the human diet. Although species, trophic level, and means of production are typically considered in predicting fish pollutant load, and thus recommendations of consumption, capture location is usually not accounted for. Objectives: Yellowfin tuna (Thunnus albacares) are harvested from across the world’s oceans and are widely consumed. Here, we determined geographic variation in the overall mass, concentration, and composition of POPs in yellowfin and examined the differences in levels of several POP congeners of potential relevance to human health. Methods: We sampled dorsal muscle of 117 yellowfin tuna from 12 locations worldwide, and measured POP levels using combined liquid or gas chromatography and mass spectrometry according to U.S. Environmental Protection Agency standard procedures. Results: POP levels varied significantly among sites, more than 36-fold on a mass basis. Individual fish levels ranged from 0.16 to 138.29ng/g wet weight and lipid-normalized concentrations from 0.1 to 12.7μM. Levels of 10 congeners that interfere with the cellular defense protein P-glycoprotein, termed transporter interfering compounds (TICs), ranged from 0.05 to 35.03ng/g wet weight and from 0.03 to 3.32μM in tuna lipid. Levels of TICs, and their individual congeners, were strongly associated with the overall POP load. Risk-based analysis of several carcinogenic POPs indicated that the fish with the highest levels of these potentially harmful compounds were clustered at specific geographic locations. Conclusions: Capture location is an important consideration when assessing the level and risk of human exposure to POPs through ingestion of wild fish. https://doi.org/10.1289/EHP518 PMID:28686554

Survey of the Anaerobic Biodegradation Potential of Organic Chemicals in Digesting Sludge

PubMed Central

Battersby, Nigel S.; Wilson, Valerie

1989-01-01

The degradation potential of 77 organic chemicals under methanogenic conditions was examined with an anaerobic digesting sludge from the United Kingdom. Degradation was assessed in terms of net total gas (CH4 plus CO2) produced, expressed as a percentage of the theoretical production (ThGP). The compounds tested were selected from various chemical groups and included substituted phenols and benzoates, pesticides, phthalic acid esters, homocyclic and heterocyclic ring compounds, glycols, and monosubstituted benzenes. The results obtained were in good agreement with published surveys of biodegradability in U.S. digesting sludges and other methanogenic environments. In general, the presence of chloro or nitro groups inhibited anaerobic gas production, while carboxyl and hydroxyl groups facilitated biodegradation. The relationship between substituent position and susceptibility to methanogenic degradation was compound dependent. The following chemicals were completely degraded (≥80% ThGP) at a concentration of 50 mg of carbon per liter: phenol, 2-aminophenol, 4-cresol, catechol, sodium benzoate, 4-aminobenzoic acid, 3-chlorobenzoic acid, phthalic acid, ethylene glycol, diethylene glycol, triethylene glycol, sodium stearate, and quinoline. 3-Cresol, 4-chlorobenzoic acid, dimethyl phthalate, and pyridine were partially degraded. Although the remaining chemicals tested were either persistent or toxic, their behavior may differ at more environmentally realistic chemical-to-biomass ratios. Our findings suggest that biodegradability assessments made with sludge from one source can be extrapolated to sludge from another source with a reasonable degree of confidence and should help in predicting the fate of an organic chemical during the anaerobic digestion of sewage sludge. PMID:16347851

Evaluation of soil contamination in intensive agricultural areas by pesticides and organic pollutants: south-eastern Spain as a case study.

PubMed

Plaza-Bolaños, Patricia; Padilla-Sánchez, Juan Antonio; Garrido-Frenich, Antonia; Romero-González, Roberto; Martínez-Vidal, José Luis

2012-04-01

A comprehensive survey of the occurrence and fate of pesticides and organic contaminants in soils from an intensive agricultural area devoted to horticultural production in plastic-based greenhouses has been performed to determine if the operation under integrated pest management practices has contributed to reduce the levels of these compounds. Almería province (south-eastern Spain) was selected for the case study. 38 agricultural soil samples (each sample corresponds to an independent private greenhouse) of areas working under integrated pest management (IPM) programs have been analyzed in order to evaluate their contamination fate. Sampling was designed to cover an area of about 400 km(2). Pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phenolic compounds and di-(2-ethylhexyl)phthalate (DEHP) were monitored. The obtained results were compared to other studies reported in Spain and Europe. Among relevant persistent pesticides, DDTs and endosulfans were mainly found and the results indicated historical application, although recent application of endosulfan was rarely detected. PAHs were also found but to a lesser extent and derived from pyrogenic sources. DEHP levels were considerably higher in comparison to the other monitored analytes. The evaluation revealed that despite the use of IPM programs, pesticide and organic contaminants are still being detected in this type of agricultural soil, although at relatively low concentration levels. In general, the contamination rate was similar or lower in comparison to other agricultural areas from nearby regions or countries. However, further monitoring studies should be carried out to establish the possible reduction in contamination by the selected compounds.

Weed seed persistence and microbial abundance in long-term organic and conventional cropping systems

USDA-ARS?s Scientific Manuscript database

Weed seed persistence in soil can be influenced by many factors, including crop management. This research was conducted to determine whether organic management systems with higher organic amendments and soil microbial biomass could reduce weed seed persistence compared to conventional management sy...

Polybrominated diphenyl ethers in marine ecosystems of the American continents: foresight from current knowledge.

PubMed

Shaw, Susan D; Kannan, Kurunthachalam

2009-01-01

Polybrominated diphenyl ethers (PBDEs) are a class of synthetic halogenated organic compounds used in commercial and household products, such as textiles, furniture, and electronics, to increase their flame ignition resistance and to meet fire safety standards. The demonstrated persistence, bioaccumulation, and toxic potential of these compounds in animals and in humans are of increasing concern. The oceans are considered global sinks for PBDEs, as higher levels are found in marine organisms than in terrestrial biota. For the past three decades, North America has dominated the world market demand for PBDEs, consuming 95% of the penta-BDE formulation. Accordingly, the PBDE concentrations in marine biota and people from North America are the highest in the world and are increasing. Despite recent restrictions on penta- and octa-BDE commercial formulations, penta-BDE containing products will remain a reservoir for PBDE release for years to come, and the deca-BDE formulation is still in high-volume use. In this paper, we review all available data on the occurrence and trends of PBDEs in the marine ecosystems (air, water, sediments, invertebrates, fish, seabirds, and marine mammals) of North and South America. We outline here our concerns about the potential future impacts of large existing stores of banned PBDEs in consumer products, and the vast and growing reservoirs of deca-BDE as well as new and naturally occurring brominated compounds on marine ecosystems.

Recombinant cells and organisms having persistent nonstandard amino acid dependence and methods of making them

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

Church, George M.; Mandell, Daniel J.; Lajoie, Marc J.

Recombinant cells and recombinant organisms persistently expressing nonstandard amino acids (NSAAs) are provided. Methods of making recombinant cells and recombinant organisms dependent on persistently expressing NSAAs for survival are also provided. These methods may be used to make safe recombinant cells and recombinant organisms and/or to provide a selective pressure to maintain one or more reassigned codon functions in recombinant cells and recombinant organisms.

Cloud processing of organic compounds: Secondary organic aerosol and nitrosamine formation

NASA Astrophysics Data System (ADS)

Hutchings, James W., III

Cloud processing of atmospheric organic compounds has been investigated through field studies, laboratory experiments, and numerical modeling. Observational cloud chemistry studies were performed in northern Arizona and fog studies in central Pennsylvania. At both locations, the cloud and fogs showed low acidity due to neutralization by soil dust components (Arizona) and ammonia (Pennsylvania). The field observations showed substantial concentrations (20-5500 ng•L -1) of volatile organic compounds (VOC) in the cloud droplets. The potential generation of secondary organic aerosol mass through the processing of these anthropogenic VOCs was investigated through laboratory and modeling studies. Under simulated atmospheric conditions, in idealized solutions, benzene, toluene, ethylbenzene, and xylene (BTEX) degraded quickly in the aqueous phase with half lives of approximately three hours. The degradation process yielded less volatile products which would contribute to new aerosol mass upon cloud evaporation. However, when realistic cloud solutions containing natural organic matter were used in the experiments, the reaction kinetics decreased with increasing organic carbon content, resulting in half lives of approximately 7 hours. The secondary organic aerosol (SUA) mass formation potential of cloud processing of BTEX was evaluated. SOA mass formation by cloud processing of BTEX, while strongly dependent on the atmospheric conditions, could contribute up to 9% of the ambient atmospheric aerosol mass, although typically ˜1% appears realistic. Field observations also showed the occurrence of N-nitrosodimethylamine (NDMA), a potent carcinogen, in fogs and clouds (100-340 ng•L -1). Laboratory studies were conducted to investigate the formation of NDMA from nitrous acid and dimethylamine in the homogeneous aqueous phase within cloud droplets. While NDMA was produced in the cloud droplets, the low yields (<1%) observed could not explain observational concentrations. Therefore heterogeneous or gaseous formation of NDMA with partitioning to droplet must be the source of aqueous NDMA. Box-model calculations tended to demonstrate a predominance of a gas phase formation mechanism followed by partitioning into the cloud droplets. The calculations were consistent with field measurements of gaseous and aqueous NDMA concentrations. Measurements and model calculations showed that while NDMA is eventually photolyzed, it might persist in the atmosphere for hours.

Profile distribution of polycyclic aromatic hydrocarbons in soils of drained peatlands after wildfires (Moscow region, Russia)

NASA Astrophysics Data System (ADS)

Tsibart, Anna; Gennadiev, Alexander; Koshovskii, Timur; Kovach, Roman

2014-05-01

Polycyclic aromatic compounds (PAHs) are formed in different natural and anthropogenic processes and could be found in many landscape components. These compounds are carcinogenic and belong to the group of persistent organic pollutants. The anthropogenic sources of PAHs are well-studied, but insufficient data are available on the hightemperature production of PAHs in natural processes. For example, natural fires are frequently related to the PAHs sources in landscapes, but very little factual data are on this topic. The soils of drained peatlands affected by catastrophic wildfires of 2010 and 2002 were studied in the Eastern part of Moscow Region (Russia). A total of 14 profiles of histosols and histic podsols were investigated. These series included soils of plots subjected to fires of different intensities and age, as well as soils of the background plots. Soil samples were taken from genetic horizons and from every 10 cm. The samples were analyzed for the contents of 14 prevailing individual compounds: fluorene, naphthalene, phenanthrene, chrysene, pyrene, anthracene, tetraphene, benz[a]pyrene, benzo[ghi]perylene, benzo[e]pyrene, coronene, dibenztiophene, triphenilene, benz(k)fluorantene. Morfological properties of soils after wildfires on drained peatlands were changed dramatically, the horizons of ash and char instead of organic layers were formed. These new horizons differ in the capability of PAHs accumulation. The char horizons have the highest concentrations of PAHs - up to 300 ng/g because of incomplete burning of organic matter in this sites, and the ash horizons, where the complete burning occured, contain only 10 ng/g PAHs. The highest concentrations of PAHs in soil profiles were detected after recent fires, and in cases of thick peat layers. After the combustion of peat chrysene, benz[a]pyrene, benz[e]pyrene, benzo[ghi]perylene, benz(k)fluorantene and tetraphene accumulated in soils. This is mainly the group of 4-6-nuclear compounds. The formation of high-molecular weight compounds is possible during smoldering process under a low oxygen supply. The oxygen deficit acts as a factor of the organic fragments recombination and PAHs production; therefore, relatively large amounts of PAHs are formed in peat fires. Moreover the peat fires occur directly in the soil layer; therefore, larger amounts of the resulting PAHs remain in the soils of the fire sites. The migration of low-molecular weight compounds occures in histic podsols, in histosols PAHs accumalate only in upper organic horizons. The research was conducted with the support of Russian Geographical Society.

CTEPP OVERVIEW: A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS

EPA Science Inventory

The research study, "Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants," (CTEPP) is a pilot-scale project involving about 260 children in their everyday surroundings. The objectives of CTEPP are twofold: (1) To measure the agg...

Investigation of the fate of sulfonamides downgradient of a decommissioned sewage farm near Berlin, Germany

NASA Astrophysics Data System (ADS)

Richter, Doreen; Massmann, Gudrun; Taute, Thomas; Duennbier, Uwe

2009-05-01

The drinking water production of a drinking water treatment plant in Berlin is affected by ambient contaminated groundwater. The three organic compounds para-toluenesulfonamide (p-TSA), ortho-toluenesulfonamide (o-TSA) and benzenesulfonamide (BSA) were identified in the catchment area of this plant. The groundwater pollution is a result of former sewage farm irrigation in the area, operating for almost 70 years until the 1980s. The distribution of the sulfonamides in the anoxic groundwater was investigated, and a large number of observation and production wells were sampled for this purpose. The contaminant plume is 25 m * 3000 m * 2000 m (depth, length, width) in size. The high concentrations of p-TSA, o-TSA and BSA in the groundwater show that the sulfonamides persist over decades in an anoxic aquifer environment. Groundwater quality assessment revealed that elevated concentrations of the analytes can be expected in the abstraction well galleries in the future. Therefore, sulfonamides should periodically be monitored in the drinking water (maximum allowed concentration of 0.30 µg/L of p-TSA and for o-TSA and BSA, a limit of 0.10 µg/L for unknown substances applies). Because of the widespread application and the persistence of the sulfonamides under anoxic conditions, our local investigations suggest that the substances may generally be present in groundwater under the influence of sewage irrigation. Incubation experiments were conducted under in situ hydrostatic pressure to study the behaviour of these trace organic compounds under different redox conditions (oxic and anoxic). Groundwater sampling equipment was either sterilised or not sterilised in order to distinguish between microbiological processes occurring in the aquifer and those representing sampling and storage artefacts (incubation experiments). Results showed that the addition of oxygen to the anoxic groundwater facilitates p-TSA and o-TSA degradation. Hence, while the substances are persistent under anoxic conditions, they are more degradable in the presence of oxygen. Results also illustrate that maintaining anoxic conditions or applying appropriate preservation techniques is necessary to ensure accurate analysis.

Uncertainties in monitoring of SVOCs in air caused by within-sampler degradation during active and passive air sampling

NASA Astrophysics Data System (ADS)

Melymuk, Lisa; Bohlin-Nizzetto, Pernilla; Prokeš, Roman; Kukučka, Petr; Přibylová, Petra; Vojta, Šimon; Kohoutek, Jiří; Lammel, Gerhard; Klánová, Jana

2017-10-01

Degradation of semivolatile organic compounds (SVOCs) occurs naturally in ambient air due to reactions with reactive trace gases (e.g., ozone, NOx). During air sampling there is also the possibility for degradation of SVOCs within the air sampler, leading to underestimates of ambient air concentrations. We investigated the possibility of this sampling artifact in commonly used active and passive air samplers for seven classes of SVOCs, including persistent organic pollutants (POPs) typically covered by air monitoring programs, as well as SVOCs of emerging concern. Two active air samplers were used, one equipped with an ozone denuder and one without, to compare relative differences in mass of collected compounds. Two sets of passive samplers were also deployed to determine the influence of degradation during longer deployment times in passive sampling. In active air samplers, comparison of the two sampling configurations suggested degradation of particle-bound polycyclic aromatic hydrocarbons (PAHs), with concentrations up to 2× higher in the denuder-equipped sampler, while halogenated POPs did not have clear evidence of degradation. In contrast, more polar, reactive compounds (e.g., organophosphate esters and current use pesticides) had evidence of losses in the sampler with denuder. This may be caused by the denuder itself, suggesting sampling bias for these compounds can be created when typical air sampling apparatuses are adapted to limit degradation. Passive air samplers recorded up to 4× higher concentrations when deployed for shorter consecutive sampling periods, suggesting that within-sampler degradation may also be relevant in passive air monitoring programs.

Gas-phase organics in environmental tobacco smoke. 1. Effects of smoking rate, ventilation, and furnishing level on emission factors.

PubMed

Singer, Brett C; Hodgson, Alfred T; Guevarra, Karla S; Hawley, Elisabeth L; Nazaroff, William W

2002-03-01

We measured the emissions of 26 gas-phase organic compounds in environmental tobacco smoke (ETS) using a model room that simulates realistic conditions in residences and offices. Exposure-relevant emission factors (EREFs), which include the effects of sorption and re-emission over a 24-h period, were calculated by mass balance from measured compound concentrations and chamber ventilation rates in a 50-m3 room constructed and furnished with typical materials. Experiments were conducted at three smoking rates (5, 10, and 20 cigarettes day(-1)), three ventilation rates (0.3, 0.6, and 2 h(-1)), and three furnishing levels (wallboard with aluminum flooring, wallboard with carpet, and full furnishings). Smoking rate did not affect EREFs, suggesting that sorption was linearly related to gas-phase concentration. Furnishing level and ventilation rate in the model room had little effect on EREFs of several ETS compounds including 1,3-butadiene, acrolein, acrylonitrile, benzene, toluene, and styrene. However, sorptive losses at low ventilation with full furnishings reduced EREFs for the ETS tracers nicotine and 3-ethenylpyridine by as much as 90 and 65% as compared to high ventilation, wallboard/aluminum experiments. Likewise, sorptive losses were 40-70% for phenol, cresols, naphthalene, and methylnaphthalenes. Sorption persisted for many compounds; for example, almost all of the sorbed nicotine and most of the sorbed cresol remained sorbed 3 days after smoking. EREFs can be used in models and with ETS tracer-based methods to refine and improve estimates of exposures to ETS constituents.

An innovative ultrasound assisted extraction micro-scale cell combined with gas chromatography/mass spectrometry in negative chemical ionization to determine persistent organic pollutants in air particulate matter.

PubMed

Beristain-Montiel, E; Villalobos-Pietrini, R; Arias-Loaiza, G E; Gómez-Arroyo, S L; Amador-Muñoz, O

2016-12-16

New clean technologies are needed to determine concentration of organic pollutants without generating more pollution. A method to extract Persistent Organic Pollutants (POPs) from airborne particulate matter was developed using a novel technology recently patented called ultrasound assisted extraction micro-scale cell (UAE-MSC). This technology extracts, filters, collects the sample, and evaporates the solvent, on-line. No sample transfer is needed. The cell minimizes sample manipulation, solvent consumption, waste generation, time, and energy; fulfilling most of the analytical green chemistry protocol. The methodology was optimized applying a centred 2 3 factorial experimental design. Optimum conditions were used to validate and determine concentration of 16 organochlorine pesticides (OCls) and 6 polybrominated diphenyl ethers (PBDEs). The best conditions achieved were 2 extractions with 5mL (each) of dichloromethane over 5min (each) at 60°C and 80% ultrasound potency. POPs were determined by gas chromatography/mass spectrometry in negative chemical ionization (GC/MS-NCI). Analytical method validation was carried out on airborne particles spiked with POPs at seven concentration levels between 0.5 and 26.9pgm -3 . This procedure was done by triplicate (N=21). Recovery, ranged between 65.5±2.3% and 107.5±3.0% for OCls and between 79.1±6.5% and 105.2±3.8% for PBDEs. Linearity (r 2 ) was ≥0.94 for all compounds. Method detection limits, ranged from 0.5 to 2.7pgm -3 , while limits of quantification (LOQ), ranged from 1.7 to 9.0pgm -3 . A Bias from -18.6% to 9% for PBDEs was observed in the Standard Reference Material (SRM) 2787. SRM 2787 did not contain OCls. OCls recoveries were equivalent by UAE-MSC and Soxhlet methods UAE-MSC optimized extraction conditions reduced 30 times less solvent and decreased the extraction time from several hours to ten minutes, respect to Soxhlet. UAE-MSC was applied to 15 samples of particles less than 2.5μm (PM 2.5 ) from three seasons (warm dry, rainy, and cold dry) collected in five sites around Mexico City. OCls (4,4'-DDE and endrin aldehyde) concentrations ranged from

Evaluation of Ricinus communis L. for the Phytoremediation of Polluted Soil with Organochlorine Pesticides

PubMed Central

Rissato, Sandra Regina; Galhiane, Mário Sergio; Fernandes, João Roberto; Gomes, Homero Marques; Ribeiro, Renata; de Almeida, Marcos Vinícius

2015-01-01

Phytoremediation is an attractive alternative to conventional treatments of soil due to advantages such as low cost, large application areas, and the possibility of in situ treatment. This study presents the assessment of phytoremediation processes conducted under controlled experimental conditions to evaluate the ability of Ricinus communis L., tropical plant species, to promote the degradation of 15 persistent organic pollutants (POPs), in a 66-day period. The contaminants tested were hexachlorocyclohexane (HCH), DDT, heptachlor, aldrin, and others. Measurements made in rhizosphere soil indicate that the roots of the studied species reduce the concentration of pesticides. Results obtained during this study indicated that the higher the hydrophobicity of the organic compound and its molecular interaction with soil or root matrix the greater its tendency to concentrate in root tissues and the research showed the following trend: HCHs < diclofop-methyl < chlorpyrifos < methoxychlor < heptachlor epoxide < endrin < o,p′-DDE < heptachlor < dieldrin < aldrin < o,p′-DDT < p,p′-DDT by increasing order of log K ow values. The experimental results confirm the importance of vegetation in removing pollutants, obtaining remediation from 25% to 70%, and demonstrated that Ricinus communis L. can be used for the phytoremediation of such compounds. PMID:26301249

The Fox River PCB transport study: Stepping stone to a healthy Great Lakes ecosystem

USGS Publications Warehouse

Fitzgerald, Sharon A.; Steuer, Jeffrey J.

1996-01-01

Polychlorinated Biphenyls (PCBs) in the Great Lakes Despite being banned since the 1970's, polychlorinated biphenyls (PCBs) continue to pose a threat to the environment because of their persistence and toxicity to organisms ranging from minute algae to fish, waterfowl, and human beings. PCBs, a set of 209 related chlorinated organic compounds, had various industrial uses such as in hydraulic fluids, cutting oils, sealants, and pesticides. Despite the manufacturing ban in the mid-1970's, PCBs remain ubiquitous in the environment. In the Laurentian Great Lakes of the Midwest. PCBs and other toxic compounds contaminate bottom sediments at almost all designated "areas of concern" (AOC)(figure 1, upper left inset). The International Joint Commission, a binational group from Canada and the United States, has identified these AOCs in their efforts to restore and protect Great Lakes ecosystems. One such area, the Fox River which flows into Green Bay, has been the focus of much scientific study in an effort to improve not only that river but to apply lessons learned to other AOCs. The final goal is a healthy Great Lakes food chain with fish and waterfowl that are safe to consume.

Dehalogenation of persistent halogenated organic compounds: A review of computational studies and quantitative structure-property relationships.

PubMed

Luo, Jin; Hu, Jiwei; Wei, Xionghui; Fu, Liya; Li, Lingyun

2015-07-01

Dehalogenation is one of the highly important degradation reactions for halogenated organic compounds (HOCs) in the environment, which is also being developed as a potential type of the remediation technologies. In combination with the experimental results, intensive efforts have recently been devoted to the development of efficient theoretical methodologies (e.g. multi-scale simulation) to investigate the mechanisms for dehalogenation of HOCs. This review summarizes the structural characteristics of neutral molecules, anionic species and excited states of HOCs as well as their adsorption behavior on the surface of graphene and the Fe cluster. It discusses the key physiochemical properties (e.g. frontier orbital energies and thermodynamic properties) calculated at various levels of theory (e.g. semiempirical, ab initio, density functional theory (DFT) and the periodic DFT) as well as their connections to the reactivity and reaction pathway for the dehalogenation. This paper also reviews the advances in the linear and nonlinear quantitative structure-property relationship models for the dehalogenation kinetics of HOCs and in the mathematical modeling of the dehalogenation processes. Furthermore, prospects of further expansion and exploration of the current research fields are described in this article. Published by Elsevier Ltd.

ANALYTICAL METHODS DEVELOPED FOR THE CHILDREN'S TOTAL EXPOSURES TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP) STUDY

EPA Science Inventory

The Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) study was designed by the U.S. EPA to collect data on young children's exposures to pesticides and other pollutants in their everyday environments in support of the Food Quality...

PERSISTENT, BIOACCUMULATIVE, AND TOXIC POLLUTANTS (PBTS)

EPA Science Inventory

Article describes the class of compounds known as persistent, bioaccumulative, and toxic pollutants (known as PBTs), including the mechanisms responsible for ability to build up the food chain and for causing adverse health effects and ecosystem damage. Exposure to numerous PBTs ...

Discovery of Emerging Per-and Polyfluoroalkyl Substances

EPA Science Inventory

Legacy perfluorinated compounds exhibit significant environmental persistence and bioaccumulation potential, which has spawned an ongoing effort to introduce replacement compounds with reduced toxicological risk profiles. Many of these emerging chemical species lack validated qua...

Perfluorinated Compounds In The Ohio River Basin

EPA Science Inventory

Contaminants of emerging concern (CECs) in waterways include pharmaceuticals and personal care products (PPCPs), alkylphenols, endocrine disrupting chemicals (EDCs) and perfluorinated alkyl compounds (PFCs). Their distributions and persistence in the aquatic environment remain p...

A cell-based assay to assess the persistence of action of agonists acting at recombinant human beta(2) adrenoceptors.

PubMed

Summerhill, Susan; Stroud, Timothy; Nagendra, Roshini; Perros-Huguet, Christelle; Trevethick, Michael

2008-01-01

The aim was to establish a robust, 96-well, cell-based assay to assess the potency and persistence of action of agonists acting at human recombinant beta(2) adrenoceptors expressed in CHO (Chinese Hamster Ovary) cells and to compare this with published duration of action data in guinea pig isolated trachea and human bronchus. Cells were treated with either: (i) beta-adrenoceptor agonist for 30 min, washed and cyclicAMP (cAMP) measured 30 min later-termed 'washed' cells or, (ii) treated with solvent for 30 min, washed, and then treated with beta-adrenoceptor agonist for 30 min and cAMP measured-termed 'unwashed' cells. The 'washed' EC(50) was divided by the 'unwashed' EC(50) to determine a rightward shift concentration ratio, which was indicative of the persistence of action at the receptor. At the beta(2) adrenoceptor salmeterol, carmoterol and indacaterol were resistant to washing with a concentration ratio of <5, indicating a long persistence of action, whereas formoterol, isoprenaline and salbutamol were washed out with a ratio of 32, >294 and >800 respectively, suggesting a shorter persistence of action. At beta(1) and beta(3) adrenoceptors all compounds washed out. The persistent effects of salmeterol at beta(2) following washing could be reversed by the selective beta(2) antagonist ICI 118551, suggesting continued receptor activation. The data presented agree well with published data assessing duration of action of beta(2) agonists in human isolated bronchus and guinea pig isolated trachea. Key features are: (a) it is a 96-well format which can be used to assess many compounds in a single experiment, (b) both potency and persistence of agonist action are assessed in the same assay, (c) any effects of concentration on the persistence of action can be highlighted, and (d) it allows triage of compounds prior to tissue bath studies thus reducing the use of animal tissue.

Investigating a persistent odor at an aircraft seat manufacturer.

PubMed

Broadwater, Kendra; de Perio, Marie A; Roberts, Jennifer; Burton, Nancy C; Lemons, Angela R; Green, Brett J; Brueck, Scott E

2016-10-01

An aircraft seat manufacturing company requested a NIOSH health hazard evaluation to help identify a strong odor that had persisted throughout the facility for over a year. Employees reported experiencing health effects thought to be related to the odor. We collected and analyzed area air samples for volatile organic compounds, endotoxin, bacterial and fungal metagenome, and metalworking fluid aerosol. Bulk metalworking fluid samples were analyzed for endotoxin, bacterial and fungal metagenome, and viable bacteria and fungus. We also evaluated the building ventilation systems and water diversion systems. Employees underwent confidential medical interviews about work practices, medical history, and health concerns. Based on our analyses, the odor was likely 2-methoxy-3,5-dimethylpyrazine. This pyrazine was found in air samples across the facility and originated from bacteria in the metalworking fluid. We did not identify bacteria known to produce the compound but bacteria from the same Proteobacteria order were found as well as bacteria from orders known to produce other pyrazines. Chemical and biological contaminants and odors could have contributed to health symptoms reported by employees, but it is likely that the symptoms were caused by several factors. We provided several recommendations to eliminate the odor including washing and disinfecting the metalworking machines and metalworking fluid recycling equipment, discarding all used metalworking fluid, instituting a metalworking fluid maintenance program at the site, and physically isolating the metalworking department from other departments.

Investigating a persistent odor at an aircraft seat manufacturer

PubMed Central

Broadwater, Kendra; de Perio, Marie A.; Roberts, Jennifer; Burton, Nancy C.; Lemons, Angela R.; Green, Brett J.; Brueck, Scott E.

2017-01-01

An aircraft seat manufacturing company requested a NIOSH health hazard evaluation to help identify a strong odor that had persisted throughout the facility for over a year. Employees reported experiencing health effects thought to be related to the odor. We collected and analyzed area air samples for volatile organic compounds, endotoxin, bacterial and fungal metagenome, and metalworking fluid aerosol. Bulk metalworking fluid samples were analyzed for endotoxin, bacterial and fungal metagenome, and viable bacteria and fungus. We also evaluated the building ventilation systems and water diversion systems. Employees underwent confidential medical interviews about work practices, medical history, and health concerns. Based on our analyses, the odor was likely 2-methoxy-3,5-dimethylpyrazine. This pyrazine was found in air samples across the facility and originated from bacteria in the metalworking fluid. We did not identify bacteria known to produce the compound but bacteria from the same Proteobacteria order were found as well as bacteria from orders known to produce other pyrazines. Chemical and biological contaminants and odors could have contributed to health symptoms reported by employees, but it is likely that the symptoms were caused by several factors. We provided several recommendations to eliminate the odor including washing and disinfecting the metalworking machines and metalworking fluid recycling equipment, discarding all used metal-working fluid, instituting a metalworking fluid maintenance program at the site, and physically isolating the metalworking department from other departments. PMID:27494786

[Detection of organic compounds on Mars].

PubMed

Kobayashi, K

1997-03-01

McKay et al. detected polycyclic aromatic hydrocarbons (PAHs) in Martian meteorite ALH 84001 by two-step laser mass spectrometry. From the presence of PAHs, together with other results, they concluded that there were past life of Mars. On the other hands, no organisms nor organic compounds were detected in Martian regolith in Viking experiments in 1976. In order to obtain solid evidence for organisms or bioorganic compounds compounds on Mars, further analyses of Martian samples are required. There may be four classes of organic compounds on Mars, which are (i) organic compounds abiotically formed from primitive Mars atmosphere, (ii) Organic compounds delivered out of Mars, (iii) Organic compounds biotically formed by Mars organisms, and (iv) Organic compounds abiotically formed from the present Mars atmosphere. Possible organic compounds on Mars and analytical methods for them are discussed.

Human biomonitoring reference values for some non-persistent chemicals in blood and urine derived from the Canadian Health Measures Survey 2009-2013.

PubMed

Khoury, Cheryl; Werry, Kate; Haines, Douglas; Walker, Mike; Malowany, Morie

2018-05-01

The Canadian Health Measures Survey collects nationally representative human biomonitoring data on a suite of chemicals and their metabolites, including many non-persistent chemicals. Data has been collected on non-persistent chemicals, including acrylamide, chlorophenols, environmental phenols and triclocarban, organophosphate insecticides, phthalates, polycyclic aromatic hydrocarbon, pyrethroid insecticides, and volatile organic compounds from 2009 to 2013. Using a systematic approach building on the reference interval concept proposed by the International Federation of Clinical Chemistry and Laboratory Medicine and the International Union of Pure and Applied Chemistry, we derive human biomonitoring reference values (RV 95 s) for these classes of non-persistent chemicals in blood and urine for the general Canadian population. RV 95 s were derived for biomarkers of non-persistent chemicals with widespread detection in Canadians (>66% detection rate). Samples with urinary creatinine levels outside the recommended range of 0.3-3.0 μg/L were excluded. Reference populations were constructed by applying smoking and fasting as exclusion criteria where appropriate. Age and sex were evaluated as possible partitioning criteria and separate RV 95 s were derived for sub-populations in cases where partitioning was deemed necessary. Reference values were derived for 40 biomarkers and represent the first set of RV 95 s for non-persistent chemicals in the general Canadian population. These values provide a measure of the upper margin of background exposure in the general population and can be compared against individual and population human biomonitoring data. RV 95 s can be used to by public health officials to identify individuals with high exposures, and by risk assessors and risk managers to identify atypical exposures or subpopulations with elevated exposures. Crown Copyright © 2018. Published by Elsevier GmbH. All rights reserved.

Various causes behind the desorption hysteresis of carboxylic acids on mudstones.

PubMed

Rasamimanana, S; Lefèvre, G; Dagnelie, R V H

2017-02-01

Adsorption desorption is a key factor for leaching, migration and (bio)degradation of organic pollutants in soils and sediments. Desorption hysteresis of apolar organic compounds is known to be correlated with adsorption/diffusion into soil organic matter. This work focuses on the desorption hysteresis of polar organic compounds on a natural mudstone sample. Acetic, citric and ortho-phthalic acids displayed adsorption-desorption hysteresis on Callovo-Oxfordian mudstone. The non-reversible behaviours resulted from three different mechanisms. Adsorption and desorption kinetics were evaluated using 14C- and 3H-labelled tracers and an isotopic exchange method. The solid-liquid distribution ratio of acetate decreased using a NaN 3 bactericide, indicating a rapid bacterial consumption compared with negligible adsorption. The desorption hysteresis of phthalate was apparent and suppressed by the equilibration of renewal pore water with mudstone. This confirms the significant and reversible adsorption of phthalate. Finally, persistent desorption hysteresis was evidenced for citrate. In this case, a third mechanism should be considered, such as the incorporation of citrate in the solid or a chemical perturbation, leading to strong desorption resilience. The results highlighted the different pathways that polar organic pollutants might encounter in a similar environment. Data on phthalic acid is useful to predict the retarded transport of phthalate esters and amines degradation products in sediments. The behaviour of citric acid is representative of polydentate chelating agents used in ore and remediation industries. The impact of irreversible adsorption on solid/solution partitioning and transport deserves further investigation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Organizing and Typing Persistent Objects Within an Object-Oriented Framework

NASA Technical Reports Server (NTRS)

Madany, Peter W.; Campbell, Roy H.

1991-01-01

Conventional operating systems provide little or no direct support for the services required for an efficient persistent object system implementation. We have built a persistent object scheme using a customization and extension of an object-oriented operating system called Choices. Choices includes a framework for the storage of persistent data that is suited to the construction of both conventional file system and persistent object system. In this paper we describe three areas in which persistent object support differs from file system support: storage organization, storage management, and typing. Persistent object systems must support various sizes of objects efficiently. Customizable containers, which are themselves persistent objects and can be nested, support a wide range of object sizes in Choices. Collections of persistent objects that are accessed as an aggregate and collections of light-weight persistent objects can be clustered in containers that are nested within containers for larger objects. Automated garbage collection schemes are added to storage management and have a major impact on persistent object applications. The Choices persistent object store provides extensible sets of persistent object types. The store contains not only the data for persistent objects but also the names of the classes to which they belong and the code for the operation of the classes. Besides presenting persistent object storage organization, storage management, and typing, this paper discusses how persistent objects are named and used within the Choices persistent data/file system framework.

Using organic-certified rather than synthetic pesticides may not be safer for biological control agents: selectivity and side effects of 14 pesticides on the predator Orius laevigatus.

PubMed

Biondi, Antonio; Desneux, Nicolas; Siscaro, Gaetano; Zappalà, Lucia

2012-05-01

The generalist predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) is a key natural enemy of various arthropods in agricultural and natural ecosystems. Releases of this predator are frequently carried out, and it is included in the Integrated Pest Management (IPM) programs of several crops. The accurate assessment of the compatibility of various pesticides with predator activity is key for the success of this strategy. We assessed acute and sublethal toxicity of 14 pesticides on O. laevigatus adults under laboratory conditions. Pesticides commonly used in either conventional or organic farming were selected for the study, including six biopesticides, three synthetic insecticides, two sulfur compounds and three adjuvants. To assess the pesticides' residual persistence, the predator was exposed for 3d to pesticide residues on tomato sprouts that had been treated 1 h, 7 d or 14 d prior to the assay. The percentage of mortality and the sublethal effects on predator reproductive capacity were summarized in a reduction coefficient (E(x)) and the pesticides were classified according to the IOBC (International Organization for Biological Control) toxicity categories. The results showed that the pesticides greatly differed in their toxicity, both in terms of lethal and sub lethal effects, as well as in their persistence. In particular, abamectin was the most noxious and persistent, and was classified as harmful up to 14 d after the treatment, causing almost 100% mortality. Spinosad, emamectin, metaflumizone were moderately harmful until 7 d after the treatment, while the other pesticides were slightly harmful or harmless. The results, based on the combination of assessment of acute mortality, predator reproductive capacity pesticides residual and pesticides residual persistence, stress the need of using complementary bioassays (e.g. assessment of lethal and sublethal effects) to carefully select the pesticides to be used in IPM programs and appropriately time the pesticides application (as function of natural enemies present in crops) and potential releases of natural enemies like O. laevigatus. Copyright © 2012 Elsevier Ltd. All rights reserved.

Pop, heavy metal and the blues: secondary analysis of persistent organic pollutants (POP), heavy metals and depressive symptoms in the NHANES National Epidemiological Survey.

PubMed

Berk, Michael; Williams, Lana J; Andreazza, Ana C; Pasco, Julie A; Dodd, Seetal; Jacka, Felice N; Moylan, Steven; Reiner, Eric J; Magalhaes, Pedro V S

2014-07-18

Persistent environmental pollutants, including heavy metals and persistent organic pollutants (POPs), have a ubiquitous presence. Many of these pollutants affect neurobiological processes, either accidentally or by design. The aim of this study was to explore the associations between assayed measures of POPs and heavy metals and depressive symptoms. We hypothesised that higher levels of pollutants and metals would be associated with depressive symptoms. National Health and Nutrition Examination Survey (NHANES). A total of 15 140 eligible people were included across the three examined waves of NHANES. Depressive symptoms were assessed using the nine-item version of the Patient Health Questionnaire (PHQ-9), using a cut-off point of 9/10 as likely depression cases. Organic pollutants and heavy metals, including cadmium, lead and mercury, as well as polyfluorinated compounds (PFCs), pesticides, phenols and phthalates, were measured in blood or urine. Higher cadmium was positively associated with depression (adjusted Prevalence Ratios (PR)=1.48, 95% CI 1.16 to 1.90). Higher levels of mercury were negatively associated with depression (adjusted PR=0.62, 95% CI 0.50 to 0.78), and mercury was associated with increased fish consumption (n=5500, r=0.366, p<0.001). In addition, several PFCs (perfluorooctanoic acid, perfluorohexane sulfonic acid, perfluorodecanoic acid and perfluorononanoic acid) were negatively associated with the prevalence of depression. Cadmium was associated with an increased likelihood of depression. Contrary to hypotheses, many of persistent environmental pollutants were not associated or negatively associated with depression. While the inverse association between mercury and depressive symptoms may be explained by a protective role for fish consumption, the negative associations with other pollutants remains unclear. This exploratory study suggests the need for further investigation of the role of various agents and classes of agents in the pathophysiology of depression. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Accumulation of persistent organic pollutants in consumers of eel from polluted rivers compared to marketable eel.

PubMed

van den Dungen, Myrthe W; Kok, Dieuwertje E; Polder, Anuschka; Hoogenboom, Ron L A P; van Leeuwen, Stefan P J; Steegenga, Wilma T; Kampman, Ellen; Murk, Albertinka J

2016-12-01

Globally, many river sediments are seriously contaminated with persistent organic pollutants (POPs) known to accumulate in aquatic food. In the Netherlands, toxicological risks of human exposure to dioxins and dioxin-like compounds led to a ban on eel fishing in the Rhine-Meuse delta. The aim of this study is to investigate differences in serum POP levels in consumers of eel from high-polluted areas and consumers of eel from low-polluted areas or aquaculture. In total 80 Dutch men were included, aged 40-70 years, with a habitual eel consumption of at least one portion (150 g) per month. Total levels of dioxins and dioxin-like compounds were measured in serum of all participants with the DR CALUX bioassay, validated with GC-MS. For a subgroup of 38 participants extensive POP measurements were performed. We revealed that consumption of eel from polluted rivers resulted in 2.5 and up to 10 times increased levels of dioxins and polychlorinated biphenyls (PCBs) respectively compared to controls. The highest PCB levels were detected for PCB 153, with a median level of 896 ng/g lipid and a maximum level of 5000 ng/g lipid in the high-exposed group. Furthermore, hydroxylated PCB metabolites (OH-PCBs: sum of 4-OH-CB107, 4-OH-CB146, 4'-OH-CB172, and 4-OH-CB187) were 8 times higher in men who consumed eel from polluted areas, and detected at levels (median 4.5 ng/g ww) reported to cause adverse health effects. Also, the majority of the perfluoroalkyl substances (PFASs) were significantly higher in consumers of eel from pullulated areas. In conclusion, this study is the first to reveal that (past) consumption of eel from polluted rivers resulted in high body burdens of dioxins, PCBs, OH-PCBs and PFASs. We confirmed the predictions made in a former risk assessment, and the high levels of dioxins and dioxin-like compounds as well as the OH-PCBs are of health concern. Copyright © 2016 Elsevier Ltd. All rights reserved.

Brominated, chlorinated and mixed brominated/chlorinated persistent organic pollutants in European eels (Anquilla anquilla) from Latvian lakes.

PubMed

Zacs, Dzintars; Rjabova, Jekaterina; Fernandes, Alwyn; Bartkevics, Vadims

2016-01-01

Fifty-eight European eel (Anquilla anquilla) specimens collected from five Latvian lakes were investigated for six groups of persistent organic pollutants (POPs), including polychlorinated, polybrominated and mixed bromo-chloro dibenzo-p-dioxins and dibenzofurans (PCDD/DFs, PBDD/DFs and PXDD/DFs), polychlorinated and mixed bromo-chloro biphenyls (PCBs and PXBs) and polybrominated diphenyl ethers (PBDEs). PCDD/DFs and PCBs were found to occur in the range 0.85-15.8 pg Total-WHO2005-TEQ g(-1) f.w., and concentrations in most of the samples were below the maximum levels specified in European Commission Regulation (EU) No. 1259/2011. The summed concentrations of 27 PBDEs (∑PBDE) and 16 non-dioxin-like PCBs (∑NDL-PCB) were in the ranges of 0.28-26.7 and 6.37-320 ng g(-1) f.w., respectively. PBDD/DFs, PXDD/DFs and PXBs show average upper-bound concentrations of 0.05, 0.06 and 0.01 pg TEQ f.w. and collectively contributed 3.4% to the sum TEQ of dioxin-like compounds. The highest contaminant concentrations were measured in samples from lakes near the Baltic Sea and the industrialised area near Riga (Liepajas and Kisezers lakes). A correlation of POP concentration with the length of collected specimens was observed.

A Model of Extracellular Enzymes in Free-Living Microbes: Which Strategy Pays Off?

PubMed Central

Thygesen, Uffe H.; Riemann, Lasse; Stedmon, Colin A.

2015-01-01

An initial modeling approach was applied to analyze how a single, nonmotile, free-living, heterotrophic bacterial cell may optimize the deployment of its extracellular enzymes. Free-living cells live in a dilute and complex substrate field, and to gain enough substrate, their extracellular enzymes must be utilized efficiently. The model revealed that surface-attached and free enzymes generate unique enzyme and substrate fields, and each deployment strategy has distinctive advantages. For a solitary cell, surface-attached enzymes are suggested to be the most cost-efficient strategy. This strategy entails potential substrates being reduced to very low concentrations. Free enzymes, on the other hand, generate a radically different substrate field, which suggests significant benefits for the strategy if free cells engage in social foraging or experience high substrate concentrations. Swimming has a slight positive effect for the attached-enzyme strategy, while the effect is negative for the free-enzyme strategy. The results of this study suggest that specific dissolved organic compounds in the ocean likely persist below a threshold concentration impervious to biological utilization. This could help explain the persistence and apparent refractory state of oceanic dissolved organic matter (DOM). Microbial extracellular enzyme strategies, therefore, have important implications for larger-scale processes, such as shaping the role of DOM in ocean carbon sequestration. PMID:26253668

Concentrations of persistent organic pollutants (POPs) in human blood samples from Mexico City, Mexico.

PubMed

Orta-García, Sandra; Pérez-Vázquez, Francisco; González-Vega, Carolina; Varela-Silva, José Antonio; Hernández-González, Lidia; Pérez-Maldonado, Iván

2014-02-15

Studies in Mexico have demonstrated exposure to persistent organic pollutants (POPs) in people living in different sites through the country. However, studies evaluating exposure to POPs in people living in Mexico City (one of most contaminated places in the world) are scarce. Therefore, the aim of this study was to assess the levels of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its metabolite dichlorodiphenyldichloroethylene (DDE) in the blood as exposure biomarkers in people living in Mexico City. A total of 123 participants (blood donors aged 20-60 years) were recruited during 2010 in Mexico City. Quantitative analyses of blood samples were performed using gas chromatography coupled with mass spectrometry. Levels of the assessed compounds ranged from non-detectable (

A Mixture of Persistent Organic Pollutants and Perfluorooctanesulfonic Acid Induces Similar Behavioural Responses, but Different Gene Expression Profiles in Zebrafish Larvae

PubMed Central

Khezri, Abdolrahman; Fraser, Thomas W. K.; Nourizadeh-Lillabadi, Rasoul; Kamstra, Jorke H.; Berg, Vidar; Zimmer, Karin E.; Ropstad, Erik

2017-01-01

Persistent organic pollutants (POPs) are widespread in the environment and some may be neurotoxic. As we are exposed to complex mixtures of POPs, we aimed to investigate how a POP mixture based on Scandinavian human blood data affects behaviour and neurodevelopment during early life in zebrafish. Embryos/larvae were exposed to a series of sub-lethal doses and behaviour was examined at 96 h post fertilization (hpf). In order to determine the sensitivity window to the POP mixture, exposure models of 6 to 48 and 48 to 96 hpf were used. The expression of genes related to neurological development was also assessed. Results indicate that the POP mixture increases the swimming speed of larval zebrafish following exposure between 48 to 96 hpf. This behavioural effect was associated with the perfluorinated compounds, and more specifically with perfluorooctanesulfonic acid (PFOS). The expression of genes related to the stress response, GABAergic, dopaminergic, histaminergic, serotoninergic, cholinergic systems and neuronal maintenance, were altered. However, there was little overlap in those genes that were significantly altered by the POP mixture and PFOS. Our findings show that the POP mixture and PFOS can have a similar effect on behaviour, yet alter the expression of genes relevant to neurological development differently. PMID:28146072

Fate and transport of some selected PhACs in a river receiving a high load of treated sewage

NASA Astrophysics Data System (ADS)

Bendz, D.; Ginn, T. R.; Paxeus, N.

2003-04-01

Pharmaceutical active compounds (PhACs) have lately been acknowledged to constitute a risk for humans and for the terrestrial and aquatic environment. Human and veterinary applications are the main sources of PhACs in the environment and the major pathway are excretion and discharge to the environment. Sewage treatment plants (STPs) play a crucial role for the introduction of the human PhACs in the environment through its removal efficiency and by separating these compounds into two exposure pathways associated with the aquatic and the solid (sludge) phase, respectively. Actually, STPs are recognized as being the main point discharge sources of human PhACs to the aquatic environment. In this study the fate and transport of a selected human PhACs belonging to different therapeutic classes (NSAIDs- non-steroidal antiinflamatory drugs, lipid regulators, antiepileptics, antibiotics and &beta-blockers) are investigated in a small river in the very south of Sweden receiving a high load of treated wastewater. In addition to the PhACs, triclosan (commonly used biocide) was included in this study. Water samples were taken of incoming and outgoing wastewater from the treatment plant, at the effluent in the river, and along the river up to 8 kilometers downstream were the river flows into the sea. After enrichment by solid-phase extraction the compounds were analyzed using GC-MS (methylated derivatives) or LC-MS/MS. In addition to the target compounds a screening analysis of the extracts revealed the presence of other wastewater related pollutants (caffeine, flame retardants, antioxidants). Several of the investigated substances demonstrate a surprising persistence in the aquatic environment. This emphasizes the need for a broader view on the concept of persistence by taking into account the recharge/loading rate in addition to removal mechanisms; transformation, volatility and physical sequestration by solids and the influence of different environmental media (Soil organic matter, mineralogy, macroscopic physical properties etc) in various hydrological systems.

Structure-based design of diverse inhibitors of Mycobacterium tuberculosis N-acetylglucosamine-1-phosphate uridyltransferase: combined molecular docking, dynamic simulation, and biological activity.

PubMed

Soni, Vijay; Suryadevara, Priyanka; Sriram, Dharmarajan; Kumar, Santhosh; Nandicoori, Vinay Kumar; Yogeeswari, Perumal

2015-07-01

Persistent nature of Mycobacterium tuberculosis is one of the major factors which make the drug development process monotonous against this organism. The highly lipophilic cell wall, which constituting outer mycolic acid and inner peptidoglycan layers, acts as a barrier for the drugs to enter the bacteria. The rigidity of the cell wall is imparted by the peptidoglycan layer, which is covalently linked to mycolic acid by arabinogalactan. Uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc) serves as the starting material in the biosynthesis of this peptidoglycan layers. This UDP-GlcNAc is synthesized by N-acetylglucosamine-1-phosphate uridyltransferase (GlmU(Mtb)), a bi-functional enzyme with two functional sites, acetyltransferase site and uridyltransferase site. Here, we report design and screening of nine inhibitors against UTP and NAcGlc-1-P of uridyltransferase active site of glmU(Mtb). Compound 4 was showing good inhibition and was selected for further analysis. The isothermal titration calorimetry (ITC) experiments showed the binding energy pattern of compound 4 to the uridyltransferase active site is similar to that of substrate UTP. In silico molecular dynamics (MD) simulation studies, for compound 4, carried out for 10 ns showed the protein-compound complex to be stable throughout the simulation with relative rmsd in acceptable range. Hence, these compounds can serve as a starting point in the drug discovery processes against Mycobacterium tuberculosis.

Coupling passive air sampling with emission estimates and chemical fate modeling for persistent organic pollutants (POPs): a feasibility study for Northern Europe.

PubMed

Gioia, Rosalinda; Sweetman, Andy J; Jones, Kevin C

2007-04-01

Passive air samplers (polyurethane foam disks) were deployed at 23 background locations along a broadly west-east transect in 8 northern European countries and analyzed for PCBs, PBDEs, PAHs, and a range of organochlorine pesticides (HCB, DDTs, and DDEs). PCBs and PAHs were highest at the center of the transect (Denmark) and lowest in northern Norway. HCB was relatively uniformly distributed, reflecting its persistence and high degree of mixing in air. Higher DDE and DDT levels occurred in Eastern Europe and at several sites in Central Europe. PBDE levels were generally similar at all sites, but lower for some locations in Eastern Europe and Ireland. Emissions information for PCBs, HCB, and PBDEs was used as input for a multi-media chemical fate model, to generate predicted air concentrations and compare with these measured values. Different scenarios were highlighted by this exercise: (i) country and compound combinations where the national inventory gave predicted air concentrations in close agreement with those measured (e.g., PCBs in the UK); (ii) country and compound combinations where predicted concentrations were well below those measured, but where advection of emissions from elsewhere is likely to be important (e.g., PCBs in Norway); (iii) consistent underestimation of compound concentrations by the emissions modeling (i.e., HCB); and (iv) general overestimation of ambient concentrations (i.e., PBDEs). Air mass trajectory analysis showed the likely role of long-range atmospheric transport (LRAT) on national levels. In general, advection from the south and west of Europe appeared to contribute to ambient POPs levels for countries in the center and northeast of the transect. Guidelines are presented as to how countries that want to assess their POPs source inventories can do so with this relatively cheap initial screening approach.

Characterization of transboundary POP contamination in aquatic ecosystems of Pearl River delta.

PubMed

Chau, K W

2005-01-01

During the past two decades, the rapid development of the Pearl River delta leads to substantial accumulation of various toxic organic compounds. This study aims to give a preliminary characterization of the existing state of contamination in this region and to provide insight into the possible fate of persistent organic pollutants (POPs) in this estuary. The available data on POPs in water, river, estuarine sediments, soil, and marine organisms within the Pearl River delta are compiled. It is shown that it may lead to transboundary POP pollution problems at both Hong Kong and Macau Special Administration Regions located at the downstream end of the region. It is noted that the levels of DDTs and HCHs in various environmental media are at alerting levels and that fresh DDT might still be applied illegally within the region. A systematic research is required to determine both the temporal and spatial variations of all POPs in various carrying media of the Pearl River delta as a whole.

Winds of change: reducing transboundary air pollutants.

PubMed

Reuther, C G

2000-04-01

Sulfur dioxide, nitrogen oxides, volatile organic compounds, persistent organic pollutants, particulate matter, and heavy metals---air pollutants once thought to be problems that could be solved locally, where the effects occur---are all currently being discussed in international forums. A spate of meetings and agreements in recent months has shown many international governments to be more willing than ever to try to limit the amount of their air pollution that drifts into other countries. Prompting this policy shift are increasing emissions in some parts of the world, better monitoring, and an improved understanding of air pollution transport and the effects of air pollution. In most regions of the world, however, no international agreements on air pollution exist at all, while in others, many overlapping local, multilateral, and global agreements address the problem simultaneously. According to the World Health Organization, air pollution causes nearly 3 million deaths per year, and the U.S. Environmental Protection Agency estimates that ground-level ozone causes damage to U.S. crops totaling $1-2 billion each year.

Persistent organic pollutants and inorganic elements in the Balearic shearwater Puffinus mauretanicus wintering off Portugal.

PubMed

Costa, R A; Torres, J; Vingada, J V; Eira, C

2016-07-15

This study presents the first data on trace element and organic pollutant concentrations in the Critically Endangered Balearic shearwater Puffinus mauretanicus collected in 2010 and 2011 in Portugal. Trace element levels were below the threshold levels for adverse effects on birds, despite the Hg concentrations in feathers (4.35μg·g-1ww). No significant differences were detected between individuals from 2010 and 2011 except for Se concentrations in liver, feathers and muscle (higher in 2010) and Ag in liver and muscle (higher in 2011). No significant differences were detected in total concentrations of organochlorine compounds in Balearic shearwaters between years, although PCB congeners -101 and -180 presented higher concentrations in individuals from 2010. The PCB congeners -138, -153 and -180, and 4.4-DDE were detected in all individuals. This study on toxic elements and organic pollutants in wintering Balearic shearwaters provides baseline data from which deviations can be detected in the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sensory and analytical evaluations of paints with and without texanol.

PubMed

Gallagher, Michelle; Dalton, Pamela; Sitvarin, Laura; Preti, George

2008-01-01

Perception of odor can figure prominently in complaints about indoor air,yet identification of the responsible compound(s) is often difficult. For example, paint emissions contain a variety of odorous volatile organic compounds (VOCs) which maytrigger reports of irritation and upper respiratory health effects. Texanol ester alcohol (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate), a paint coalescing agent, is frequently associated with the "persistent, characteristic odor" of water-based paint. To evaluate the sensory impact of Texanol, naive (unfamiliar with paint constituents) and experienced (familiar with paint constituents) subjects evaluated the odor properties of paints with and without Texanol. VOC emissions from neat paint and paint applied to gypsum wallboard were collected via solid-phase microextraction and analyzed by gas chromatography/ mass spectrometry and gas chromatography/olfactometry. Regardless of subjects' prior experience, aromatic hydrocarbons and oxygenated compounds, introduced from other paint additives and not Texanol, were most commonly associated with paint odor. However, quantitative sensory techniques demonstrated that addition of Texanol to paints led to an overall increase in the perceived intensity of the coating. The combined use of these techniques proved to be an effective methodology for analyzing the structure of paint volatiles and their sensory properties and holds promise for solving many odorous indoor air problems.

A high-resolution conceptual model for diffuse organic micropollutant loads in streams

NASA Astrophysics Data System (ADS)

Stamm, Christian; Honti, Mark; Ghielmetti, Nico

2013-04-01

The ecological state of surface waters has become the dominant aspect in water quality assessments. Toxicity is a key determinant of the ecological state, but organic micropollutants (OMP) are seldom monitored with the same spatial and temporal frequency as for example nutrients, mainly due the demanding analytical methods and costs. However, diffuse transport pathways are at least equally complex for OMPs as for nutrients and there are still significant knowledge gaps. Moreover, concentrations of the different compounds would need to be known with fairly high temporal resolution because acute toxicity can be as important as the chronic one. Fully detailed mechanistic models of diffuse OMP loads require an immense set of site-specific knowledge and are rarely applicable for catchments lacking an exceptional monitoring coverage. Simple empirical methods are less demanding but usually work with more temporal aggregation and that's why they have limited possibilities to support the estimation of the ecological state. This study presents a simple conceptual model that aims to simulate the concentrations of selected organic micropollutants with daily resolution at 11 locations in the stream network of a small catchment (46 km2). The prerequisite is a known hydrological and meteorological background (daily discharge, precipitation and air temperature time series), a land use map and some historic measurements of the desired compounds. The model is conceptual in the sense that all important diffuse transport pathways are simulated separately, but each with a simple empirical process rate. Consequently, some site-specific observations are required to calibrate the model, but afterwards the model can be used for forecasting and scenario analysis as the calibrated process rates typically describe invariant properties of the catchment. We simulated 6 different OMPs from the categories of agricultural and urban pesticides and urban biocides. The application of agricultural pesticides was also simulated with the model using a heat-sum approach. Calibration was carried out with weekly aggregated samples covering the growing season in 2 years. The model could reproduce the observed OMP concentrations with varying success. Compounds that are less persistent in the environment and thus have a dominant temporal dynamics (pesticides with a short half-life) could be simulated in general better than the persistent ones. For the latter group the relatively stable available stock meant that there were no clear seasonal dynamics, which revealed that transport processes are quite uncertain even when daily rainfall is used as the main driver. Nevertheless the daily concentration distribution could still be simulated with higher accuracy than the individual peaks. Thus we can model the concentration-duration relationship for daily resolution in an acceptable way for each compound.

Changes in reproductive biomarkers in an endangered fish species (bonytail chub, Gila elegans) exposed to low levels of organic wastewater compounds in a controlled experiment.

PubMed

Walker, David B; Paretti, Nicholas V; Cordy, Gail; Gross, Timothy S; Zaugg, Steven D; Furlong, Edward T; Kolpin, Dana W; Matter, William J; Gwinn, Jessica; McIntosh, Dennis

2009-11-08

In arid regions of the southwestern United States, municipal wastewater treatment plants commonly discharge treated effluent directly into streams that would otherwise be dry most of the year. A better understanding is needed of how effluent-dependent waters (EDWs) differ from more natural aquatic ecosystems and the ecological effect of low levels of environmentally persistent organic wastewater compounds (OWCs) with distance from the pollutant source. In a controlled experiment, we found 26 compounds common to municipal effluent in treatment raceways all at concentrations <1.0 microg/L. Male bonytail chub (Gila elegans) in tanks containing municipal effluent had significantly lower levels of 11-ketotestosterone (p=0.021) yet higher levels of 17beta-estradiol (p=0.002) and vitellogenin (p=0.036) compared to control male fish. Female bonytail chub in treatment tanks had significantly lower concentrations of 17beta-estradiol than control females (p=0.001). The normally inverse relationship between primary male and female sex hormones, expected in un-impaired fish, was greatly decreased in treatment (r=0.00) versus control (r=-0.66) female fish. We found a similar, but not as significant, trend between treatment (r=-0.45) and control (r=-0.82) male fish. Measures of fish condition showed no significant differences between male or female fish housed in effluent or clean water. Inter-sex condition did not occur and testicular and ovarian cells appeared normal for the respective developmental stage and we observed no morphological alteration in fish. The population-level impacts of these findings are uncertain. Studies examining the long-term, generational and behavioral effects to aquatic organisms chronically exposed to low levels of OWC mixtures are needed.

Changes in reproductive biomarkers in an endangered fish species (bonytail chub, Gila elegans) exposed to low levels of organic wastewater compounds in a controlled experiment

USGS Publications Warehouse

Walker, D.B.; Paretti, N.V.; Cordy, G.; Gross, T.S.; Zaugg, S.D.; Furlong, E.T.; Kolpin, D.W.; Matter, W.J.; Gwinn, J.; McIntosh, D.

2009-01-01

In arid regions of the southwestern United States, municipal wastewater treatment plants commonly discharge treated effluent directly into streams that would otherwise be dry most of the year. A better understanding is needed of how effluent-dependent waters (EDWs) differ from more natural aquatic ecosystems and the ecological effect of low levels of environmentally persistent organic wastewater compounds (OWCs) with distance from the pollutant source. In a controlled experiment, we found 26 compounds common to municipal effluent in treatment raceways all at concentrations <1.0 ??g/L. Male bonytail chub (Gila elegans) in tanks containing municipal effluent had significantly lower levels of 11-ketotestosterone (p = 0.021) yet higher levels of 17??-estradiol (p = 0.002) and vitellogenin (p = 0.036) compared to control male fish. Female bonytail chub in treatment tanks had significantly lower concentrations of 17??-estradiol than control females (p = 0.001). The normally inverse relationship between primary male and female sex hormones, expected in un-impaired fish, was greatly decreased in treatment (r = 0.00) versus control (r = -0.66) female fish. We found a similar, but not as significant, trend between treatment (r = -0.45) and control (r = -0.82) male fish. Measures of fish condition showed no significant differences between male or female fish housed in effluent or clean water. Inter-sex condition did not occur and testicular and ovarian cells appeared normal for the respective developmental stage and we observed no morphological alteration in fish. The population-level impacts of these findings are uncertain. Studies examining the long-term, generational and behavioral effects to aquatic organisms chronically exposed to low levels of OWC mixtures are needed. ?? 2009 Elsevier B.V.

Changes in reproductive biomarkers in an endangered fish species (bonytail chub, Gila elegans) exposed to low levels of organic wastewater compounds in a controlled experiment

USGS Publications Warehouse

Walker, David B.; Paretti, Nicholas V.; Cordy, Gail; Gross, Timothy S.; Zaugg, Steven D.; Furlong, Edward T.; Kolpin, Dana W.; Matter, William J.; Gwinn, Jessica; McIntosh, Dennis

2009-01-01

In arid regions of the southwestern United States, municipal wastewater treatment plants commonly discharge treated effluent directly into streams that would otherwise be dry most of the year. A better understanding is needed of how effluent-dependent waters (EDWs) differ from more natural aquatic ecosystems and the ecological effect of low levels of environmentally persistent organic wastewater compounds (OWCs) with distance from the pollutant source. In a controlled experiment, we found 26 compounds common to municipal effluent in treatment raceways all at concentrations <1.0 μg/L. Male bonytail chub (Gila elegans) in tanks containing municipal effluent had significantly lower levels of 11-ketotestosterone (p = 0.021) yet higher levels of 17β-estradiol (p = 0.002) and vitellogenin (p = 0.036) compared to control male fish. Female bonytail chub in treatment tanks had significantly lower concentrations of 17β-estradiol than control females (p = 0.001). The normally inverse relationship between primary male and female sex hormones, expected in un-impaired fish, was greatly decreased in treatment (r = 0.00) versus control (r = −0.66) female fish. We found a similar, but not as significant, trend between treatment (r = −0.45) and control (r = −0.82) male fish. Measures of fish condition showed no significant differences between male or female fish housed in effluent or clean water. Inter-sex condition did not occur and testicular and ovarian cells appeared normal for the respective developmental stage and we observed no morphological alteration in fish. The population-level impacts of these findings are uncertain. Studies examining the long-term, generational and behavioral effects to aquatic organisms chronically exposed to low levels of OWC mixtures are needed.

How soil organic matter composition controls hexachlorobenzene-soil-interactions: adsorption isotherms and quantum chemical modeling.

PubMed

Ahmed, Ashour A; Kühn, Oliver; Aziz, Saadullah G; Hilal, Rifaat H; Leinweber, Peter

2014-04-01

Hazardous persistent organic pollutants (POPs) interact in soil with the soil organic matter (SOM) but this interaction is insufficiently understood at the molecular level. We investigated the adsorption of hexachlorobenzene (HCB) on soil samples with systematically modified SOM. These samples included the original soil, the soil modified by adding a hot water extract (HWE) fraction (soil+3 HWE and soil+6 HWE), and the pyrolyzed soil. The SOM contents increased in the order pyrolyzed soil

Analysis of annual fluctuations in the content of phenol, chlorophenols and their derivatives in chlorinated drinking waters.

PubMed

Michałowicz, Jaromir; Stufka-Olczyk, Jadwiga; Milczarek, Anna; Michniewicz, Małgorzata

2011-08-01

Chlorophenols are widely represented, toxic, and persistent environmental pollutants. In this work, we analyzed annual fluctuations in the content of phenol, guaiacol, chlorophenols, chlorocatechols, and chlorinated methoxyphenols in drinking water collected in Warsaw and Tomaszów Mazowiecki (Poland). Moreover, the effect of dissolved organic matter content on the occurrence of phenolic compounds in drinking water was studied. The compounds were adsorbed on octadecyl C18 solid-phase discs, separated by the use of gas chromatography, and analyzed using mass spectrometry. The content of organic matter was evaluated by the analysis of UV absorption at 254 nm by water samples. In Warsaw, raw water (derived from infiltration intakes situated in the Vistula River) and treated water (subjected to coagulation, filtration, and disinfection with chlorine dioxide) were collected in order to analyze phenols. In Tomaszów Mazowiecki, raw water (taken directly form the river) and treated water (subjected to coagulation, sand filtration, ozonation, and disinfection with gaseous chlorine) were taken to determine phenolic substances. The obtained results showed the occurrence of phenol, guaiacol, 2,4,6-trichlorophenol (2,4,6-TCP), tetrachlorophenol (TeCP), and pentachlorophenol in drinking water of both cities. Occasionally, in the waters studied, the appearance of chloroguaiacols, 3-chlorosyringol, and some chlorocatechols were noted. It was also observed that the content of dissolved organic matter in river waters may have contributed to the formation of some phenols, e.g., phenol, guaiacol, 2,4,6-TCP, and TeCP in drinking water. Finally, it was found that there were no annual (seasonal) fluctuations in phenolic compounds contents in drinking waters examined.

Dehydrogenation of liquid fuel in microchannel catalytic reactor

DOEpatents

Toseland, Bernard Allen; Pez, Guido Peter; Puri, Pushpinder Singh

2010-08-03

The present invention is an improved process for the storage and delivery of hydrogen by the reversible hydrogenation/dehydrogenation of an organic compound wherein the organic compound is initially in its hydrogenated state. The improvement in the route to generating hydrogen is in the dehydrogenation step and recovery of the dehydrogenated organic compound resides in the following steps: introducing a hydrogenated organic compound to a microchannel reactor incorporating a dehydrogenation catalyst; effecting dehydrogenation of said hydrogenated organic compound under conditions whereby said hydrogenated organic compound is present as a liquid phase; generating a reaction product comprised of a liquid phase dehydrogenated organic compound and gaseous hydrogen; separating the liquid phase dehydrogenated organic compound from gaseous hydrogen; and, recovering the hydrogen and liquid phase dehydrogenated organic compound.

Dehydrogenation of liquid fuel in microchannel catalytic reactor

DOEpatents

Toseland, Bernard Allen [Allentown, PA; Pez, Guido Peter [Allentown, PA; Puri, Pushpinder Singh [Emmaus, PA

2009-02-03

The present invention is an improved process for the storage and delivery of hydrogen by the reversible hydrogenation/dehydrogenation of an organic compound wherein the organic compound is initially in its hydrogenated state. The improvement in the route to generating hydrogen is in the dehydrogenation step and recovery of the dehydrogenated organic compound resides in the following steps: introducing a hydrogenated organic compound to a microchannel reactor incorporating a dehydrogenation catalyst; effecting dehydrogenation of said hydrogenated organic compound under conditions whereby said hydrogenated organic compound is present as a liquid phase; generating a reaction product comprised of a liquid phase dehydrogenated organic compound and gaseous hydrogen; separating the liquid phase dehydrogenated organic compound from gaseous hydrogen; and, recovering the hydrogen and liquid phase dehydrogenated organic compound.

Bench-scale evaluation of in situ bioremediation strategies for soil at a former manufactured gas plant site.

PubMed

Li, Jun; Pignatello, Joseph J; Smets, Barth F; Grasso, Domenico; Monserrate, Esteban

2005-03-01

We examined the biodegradation and desorption of a set of 15 polycyclic aromatic hydrocarbon (PAH) compounds in coal tar-contaminated soil at a former manufactured gas plant site to evaluate the feasibility of in situ bioremediation. Experiments were conducted in well-mixed aerobic soil suspensions containing various additives over a 93- to 106-d period. In general, both biotransformation and desorption decreased with PAH ring size, becoming negligible for the six-ring PAH compounds. Biodegradation by indigenous microorganisms was strongly accelerated by addition of inorganic nutrients (N, P, K, and trace metals). The rates of biotransformation of PAH compounds by indigenous microorganisms in nutrient-amended flasks outpaced their maximum (i.e., chelate-enhanced) rates of desorption to an infinite sink (Tenax) in sterilized systems run in parallel, suggesting that indigenous organisms facilitated desorption. Biodegradation by indigenous organisms in nutrient-amended flasks appeared to be unaffected by the addition of a site-derived bacterial enrichment culture, resulting in approximately 100-fold higher aromatic dioxygenase levels, and by the addition of 0.01 M chelating agent (citrate or pyrophosphate), although such chelating agents greatly enhanced desorption in microbially inactivated flasks. The strong ability of nutrients to enhance degradation of the bioavailable PAHs indicates that their persistence for many decades at this site likely results from nutrient-limited natural biodegradation, and it also suggests that an effective strategy for their bioremediation could consist simply of adding inorganic nutrients.

Monitoring of heavy metal and organic compound levels along the Eastern Aegean coast with transplanted mussels.

PubMed

Kucuksezgin, Filiz; Pazi, Idil; Yucel-Gier, Guzel; Akcali, Baris; Galgani, François

2013-11-01

Within the framework of the MYTITURK project, heavy metals and organic compounds contaminations were assessed in transplanted mussels in eight different bays from the Eastern Aegean coast. Izmir Bay, Canakkale Strait entrance, Saros and Candarli Bay were defined low pollution extent according to Principal Component Analysis taking into metal accumulation. PAHs (Polycyclic Aromatic Hydrocarbons) levels in the range of 29.4-64.2 ng g(-1) (dry weight) indicated that PAH contamination level classified as low along the Aegean coast. Concentrations of Aroclor1254 and 1260 were higher in transplanted mussels from Canakkale Strait Outlet due to industrial activities was originated from Marmara Sea. The organochlorinated pesticides such as heptachlor (<0.4 ng g(-1)), aldrin (<0.30 ng g(-1)), dieldrin (<0.75 ng g(-1)), endrin (<2.3 ng g(-1)) concentrations were homogeneous however, HCB (Hexachlorobenzene) and lindane concentrations were found undetectable level along the coast. DDE/DDT ratio in the caged mussels form Gulluk and Gokova Bay indicated recent DDT (Dikloro difenil trikloroethan) usage in these areas. The residues of organochlorinated compounds in transplanted mussels confirm the long persistence of DDTs. According to world health authorities, the concentration of heavy metals in mussels for the study area can generally be considered not to be at levels posing a health risk except Zn. The levels of POPs indicated that transplanted mussels have a lack of risk for the human health. Copyright © 2013 Elsevier Ltd. All rights reserved.

Application of passive sampling in assessing the occurrence and risk of antibiotics and endocrine disrupting chemicals in the Yangtze Estuary, China.

PubMed

Shi, X; Zhou, J L; Zhao, H; Hou, L; Yang, Y

2014-09-01

Polar organic chemical integrative sampler (POCIS) was used in assessing the occurrence and risk of 12 widely used antibiotics and 5 most potent endocrine disrupting chemicals (EDCs) in the Yangtze Estuary, China. During laboratory validation, the kinetics of pollutant uptake by POCIS were linear, and the sampling rates of most compounds were raised by flow rate and salinity, reaching the highest values at salinity 14‰. The sampling rates varied with the target compounds with the EDCs showing the highest values (overall average=0.123Ld(-1)), followed by chloramphenicols (0.100Ld(-1)), macrolides (0.089Ld(-1)), and finally sulfonamides (0.056Ld(-1)). Validation in the Yangtze Estuary in 2013 showed that the field sampling rates were significantly greater for all compounds except bisphenol A, in comparison to laboratory results, and high-frequency spot sampling is critical for fully validating the passive sampler. The field studies show that antibiotics were widely detected in the Yangtze Estuary, with concentrations varying from below quantification to 1613ngL(-1), suggesting their widespread use and persistence in estuarine waters. The dominating pollutants in July were sulfonamides with a total concentration of 258ngL(-1) and in October were macrolides with a total concentration of 350ngL(-1). The calculation of risk quotient suggested that sulfapyridine, sulfaquinoxaline and erythromycin-H2O may have caused medium damage to sensitive organisms such as fish. Copyright © 2014. Published by Elsevier Ltd.

Pharmaceuticals and other organic wastewater contaminants within a leachate plume downgradient of a municipal landfill

USGS Publications Warehouse

Barnes, Kimberlee K.; Christenson, Scott C.; Kolpin, Dana W.; Focazio, Michael J.; Furlong, Edward T.; Zaugg, Steven D.; Meyer, Michael T.; Barber, Larry B.

2004-01-01

Ground water samples collected from the Norman Landfill research site in central Oklahoma were analyzed as part of the U.S. Geological Survey (USGS) Toxic Substances Hydrology Program's national reconnaissance of pharmaceuticals and other organic waste water contaminants (OWCs) in ground water. Five sites, four of which are located downgradient of the landfill, were sampled in 2000 and analyzed for 76 OWCs using four research methods developed by the USGS. OWCs were detected in water samples from all of the sites sampled, with 22 of the 76 OWCs being detected at least once. Cholesterol (a plant and animal steroid), was detected at all five sites and was the only compound detected in a well upgradient of the landfill. N,Ndiethyltoluamide (DEET used in insect repellent) and tri(2-chloroethyl) phosphate (fire-retardant) were detected in water samples from all four sites located within the landfill-derived leachate plume. The sites closest to the landfill had more detections and greater concentrations of each of the detected compounds than sites located farther away. Detection of multiple OWCs occurred in the four sites located within the leachate plume, with a minimum of four and a maximum of 17 OWCs detected. Because the landfill was established in the 1920s and closed in 1985, many compounds detected in the leachate plume were likely disposed of decades ago. These results indicate the potential for long-term persistence and transport of some OWCs in ground water.

Lactate Clearance and Normalization and Prolonged Organ Dysfunction in Pediatric Sepsis.

PubMed

Scott, Halden F; Brou, Lina; Deakyne, Sara J; Fairclough, Diane L; Kempe, Allison; Bajaj, Lalit

2016-03-01

To evaluate whether lactate clearance and normalization during emergency care of pediatric sepsis is associated with lower rates of persistent organ dysfunction. This was a prospective cohort study of 77 children <18 years of age in the emergency department with infection and acute organ dysfunction per consensus definitions. In consented patients, lactate was measured 2 and/or 4 hours after an initial lactate; persistent organ dysfunction was assessed through laboratory and physician evaluation at 48 hours. A decrease of ≥ 10% from initial to final level was considered lactate clearance; a final level < 2 mmol/L was considered lactate normalization. Relative risk (RR) with 95% CIs, adjusted in a log-binomial model, was used to evaluate associations between lactate clearance/normalization and organ dysfunction. Lactate normalized in 62 (81%) patients and cleared in 70 (91%). The primary outcome, persistent 48-hour organ dysfunction, was present in 32 (42%). Lactate normalization was associated with decreased risk of persistent organ dysfunction (RR 0.46, 0.29-0.73; adjusted RR 0.47, 0.29-0.78); lactate clearance was not (RR 0.70, 0.35-1.41; adjusted RR 0.75, 0.38-1.50). The association between lactate normalization and decreased risk of persistent organ dysfunction was retained in the subgroups with initial lactate ≥ 2 mmol/L and hypotension. In children with sepsis and organ dysfunction, lactate normalization within 4 hours was associated with decreased persistent organ dysfunction. Serial lactate level measurement may provide a useful prognostic tool during the first hours of resuscitation in pediatric sepsis. Copyright © 2016 Elsevier Inc. All rights reserved.

G-quadruplex-interacting compounds alter latent DNA replication and episomal persistence of KSHV

PubMed Central

Madireddy, Advaitha; Purushothaman, Pravinkumar; Loosbroock, Christopher P.; Robertson, Erle S.; Schildkraut, Carl L.; Verma, Subhash C.

2016-01-01

Kaposi's sarcoma associated herpesvirus (KSHV) establishes life-long latent infection by persisting as an extra-chromosomal episome in the infected cells and by maintaining its genome in dividing cells. KSHV achieves this by tethering its epigenome to the host chromosome by latency associated nuclear antigen (LANA), which binds in the terminal repeat (TR) region of the viral genome. Sequence analysis of the TR, a GC-rich DNA element, identified several potential Quadruplex G-Rich Sequences (QGRS). Since quadruplexes have the tendency to obstruct DNA replication, we used G-quadruplex stabilizing compounds to examine their effect on latent DNA replication and the persistence of viral episomes. Our results showed that these G-quadruplex stabilizing compounds led to the activation of dormant origins of DNA replication, with preferential bi-directional pausing of replications forks moving out of the TR region, implicating the role of the G-rich TR in the perturbation of episomal DNA replication. Over time, treatment with PhenDC3 showed a loss of viral episomes in the infected cells. Overall, these data show that G-quadruplex stabilizing compounds retard the progression of replication forks leading to a reduction in DNA replication and episomal maintenance. These results suggest a potential role for G-quadruplex stabilizers in the treatment of KSHV-associated diseases. PMID:26837574

[Assessment of so called organic trace compounds in drinking water from the regulatory, health and aesthetic-quality points of view, with special consideration given to pharmaceuticals].

PubMed

Dieter, H H; Mückter, H

2007-03-01

More than 2500 chemically defined substances are approved as drugs in Germany. Unlike agricultural pesticides, these biologically active structures are not used in open environmental compartments and therefore their environmental toxicological data base is not nearly as complete. Nevertheless, some of them become environmental contaminants after their intended use. Therefore, from the viewpoint of environmental health protection, there are gaps in their health-related environmental risk assessment. Organic trace compounds that lack an adequate toxicological database, and their mixtures, in drinking water can be safely regulated and provisionally assessed by combining the "similar joint action" addition rule with the recommendation of the Federal Environment Agency of March 2003 "Assessing the presence of substances in drinking water without (adequate) toxicological database from the health point of view". The general precautionary value (Gesundheitlicher Orientierungswert GOW1=0.10 microg/l), which is a recommendation for weakly to not genotoxic compounds, re presents a workable compromise between preventive health protection, water management considerations and aesthetic quality claims (purity). Compliance with this value in the long term will only be possible if the chemical and biological degradation of pharmaceuticals and their metabolites in waste water and waste water treatment plants is effectively improved. Alternatively, there is the risk of drinking water degenerating into a sink for highly mobile, polar and persistent compounds. Their elimination at a stage as late as technical drinking water treatment would be neither close to the initial cause nor justifiable in terms of technical effectiveness. The risk assessment of their byproducts would give rise to further uncertainties. Possible conflicts with the therapeutic quality must be solved by developing substitute products which are environmentally sound.

Levels of Selected Persistent Organic Pollutants (PCB, PBDE) and Pesticides in Honey Bee Pollen Sampled in Poland.

PubMed

Roszko, Marek Łukasz; Kamińska, Marta; Szymczyk, Krystyna; Jędrzejczak, Renata

2016-01-01

Chemical plant protection is a commonly discussed factor potentially responsible for decline in pollinators and other beneficial insect populations. Various groups of chemicals including persistent organic pollutants could impact a bee colony's welfare and are reported to be present in bee tissue and apiary products. The aim of this work was to evaluate the presence of selected persistent organic pollutant and pesticide residues in bee pollen originating from different geographical regions of Poland. Pesticide residues were identified in 60% of tested bee pollen samples. The compounds identified were mainly active ingredients of fungicide preparations. Insecticide active ingredients were up to 30% of the identified residues. The triazole fungicide tebuconazole and the neonicotinoid insecticide thiacloprid were the most frequently found pesticides in pollen. The highest pesticide concentration was determined for prothioconazole (356 μg kg-1). Mean concentrations of chlorinated biphenyls-EC6 and EC12 were 194 pg g-1 and 74 pg g-1, respectively. CB # 28 has the greatest share in the EC6 profile (mean 61 pg g-1, 31% contribution). Relatively high contributions were also observed for CBs # 101 (35 pg g-1, 18%), # 138 (36 pg g-1, 19%) and # 153 (33 pg g-1, 17%). CB # 114 and 118 have the highest share in the dioxin-like biphenyls fraction with mean concentrations of 17.6 and 37.6 pg g-1 (respectively 23 and 50%). Mean calculated concentrations of 39 polybrominated diphenyl ether congeners (Σ39 BDE) were 20 ± 27.7 pg g-1. High variability was observed between maximal and minimal determined concentration values. Individual BDEs were found at different frequencies and varying concentration levels. BDEs # 47, 75 and 99 dominated the profile with average concentrations of 3 pg g-1, 3.1 pg g-1, and 2.9 pg g-1, respectively.

Levels of Selected Persistent Organic Pollutants (PCB, PBDE) and Pesticides in Honey Bee Pollen Sampled in Poland

PubMed Central

Roszko, Marek Łukasz; Kamińska, Marta; Szymczyk, Krystyna; Jędrzejczak, Renata

2016-01-01

Chemical plant protection is a commonly discussed factor potentially responsible for decline in pollinators and other beneficial insect populations. Various groups of chemicals including persistent organic pollutants could impact a bee colony’s welfare and are reported to be present in bee tissue and apiary products. The aim of this work was to evaluate the presence of selected persistent organic pollutant and pesticide residues in bee pollen originating from different geographical regions of Poland. Pesticide residues were identified in 60% of tested bee pollen samples. The compounds identified were mainly active ingredients of fungicide preparations. Insecticide active ingredients were up to 30% of the identified residues. The triazole fungicide tebuconazole and the neonicotinoid insecticide thiacloprid were the most frequently found pesticides in pollen. The highest pesticide concentration was determined for prothioconazole (356 μg kg-1). Mean concentrations of chlorinated biphenyls–EC6 and EC12 were 194 pg g-1 and 74 pg g-1, respectively. CB # 28 has the greatest share in the EC6 profile (mean 61 pg g−1, 31% contribution). Relatively high contributions were also observed for CBs # 101 (35 pg g−1, 18%), # 138 (36 pg g−1, 19%) and # 153 (33 pg g−1, 17%). CB # 114 and 118 have the highest share in the dioxin-like biphenyls fraction with mean concentrations of 17.6 and 37.6 pg g−1 (respectively 23 and 50%). Mean calculated concentrations of 39 polybrominated diphenyl ether congeners (Σ39 BDE) were 20 ± 27.7 pg g−1. High variability was observed between maximal and minimal determined concentration values. Individual BDEs were found at different frequencies and varying concentration levels. BDEs # 47, 75 and 99 dominated the profile with average concentrations of 3 pg g−1, 3.1 pg g−1, and 2.9 pg g−1, respectively. PMID:27907097

Use of raw or incubated organic wastes as amendments in reducing pesticide leaching through soil columns.

PubMed

Marín-Benito, J M; Brown, C D; Herrero-Hernández, E; Arienzo, M; Sánchez-Martín, M J; Rodríguez-Cruz, M S

2013-10-01

Soil amendment with organic wastes is becoming a widespread management practice since it can effectively solve the problems of uncontrolled waste accumulation and improve soil quality. However, when simultaneously applied with pesticides, organic wastes can significantly modify the environmental behaviour of these compounds. This study evaluated the effect of sewage sludges (SS), grape marc (GM) and spent mushroom substrates (SMS) on the leaching of linuron, diazinon and myclobutanil in packed columns of a sandy soil with low organic matter (OM) content (<1%). Soil plus amendments had been incubated for one month (1 m) or 12 months (12 m). Data from the experimental breakthrough curves (BTCs) were fitted to the one-dimensional transport model CXTFIT 2.1. All three amendments reduced leaching of linuron and myclobutanil relative to unamended soil. SMS was the most effective in reducing leaching of these two compounds independent of whether soil was incubated for 1 m or 12 m. Soil amendments increased retardation coefficients (Rexp) by factors of 3 to 5 for linuron, 2 to 4 for diazinon and 3 to 5 for myclobutanil relative to unamended soil. Leaching of diazinon was relatively little affected by soil amendment compared to the other two compounds and both SS and SMS amendment with 1m incubation resulted in enhanced leaching of diazinon. The leaching data for linuron and myclobutanil were well described by CXTFIT (mean square error, MSE<4.9·10(-7) and MSE<7.0·10(-7), respectively) whereas those of diazinon were less well fitted (MSE<2.1·10(-6)). The BTCs for pesticides were similar in soils incubated for one month or one year, indicating that the effect of amendment on leaching persists over relatively long periods of time. Copyright © 2013 Elsevier B.V. All rights reserved.

An integrated evaluation of the persistence and effects of 4-nonylphenol in an experimental littoral ecosystem

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

Liber, K.; Knuth, M.L.; Stay, F.S.

1999-03-01

A comprehensive littoral enclosure study was conducted to assess the persistence and distribution of 4-nonylphenol (NP) in a littoral ecosystem, and to evaluate the compound`s effects on resident aquatic biota. Enclosures with a mean ({+-} SD) surface area and volume of 31.4 {+-} 3.3 m{sup 2} and 32.0 {+-} 6.4 m{sup 3}, respectively, received eleven applications at 48-h intervals with one of four different rates of NP. This created a 20-d application period which was followed by a three to fourteen month observation period, depending on the endpoint measured. Mean {+-} SD NP concentrations in the water column measured 2more » h after each application averaged 5 {+-} 4, 23 {+-} 11, 76 {+-} 21, and 243 {+-} 41 {micro}g/L at nominal treatments of 3, 30, 100, and 300 {micro}g/L, respectively. Persistence in the water column was relatively short, with a dissipation half-life estimated at {le} 1.2 d. Persistence of NP in sediment and on macrophytes was substantially longer, with estimated half-lives of 28 to 104 d and 8 to 13 d, respectively. Zooplankton was the most sensitive group of organisms evaluated, with significant reductions in population abundances of some copepod taxa observed at the 23 {+-} 11-{micro}g/L treatment. Fish survival was affected at 243 {+-} 41 {micro}g/L. The most sensitive benthic macroinvertebrate taxon, Pisidium (Bivalvia) was affected at 76 {+-} 21 {micro}g/L, but most taxa were only affected at the 243 {+-} 41-{micro}g/L treatment. None of the assessed populations were affected at the 5 {+-} 4-{micro}g/L treatment. Macrophytes and periphyton were not adversely affected by any of the treatments. Overall community composition, assessed at the family level or higher, was not affected at or below the 23 {+-} 11-{micro}g/L treatment, but did exhibit substantial changes at the 243 {+-} 41-{micro}g/L treatment. Some minor changes were observed at the 76 {+-} 21-{micro}g/L treatment. The maximum acceptable toxicant concentration in the water column, based on protection of the most sensitive taxa in the test system, was estimated at {approximately} 10 {micro}g/L. Details on NP persistence and distribution within the enclosures, and detailed effects on zooplankton, benthic macroinvertebrates, and fish are described in four separate papers immediately following this overview.« less

Prioritizing pesticide compounds for analytical methods development

USGS Publications Warehouse

Norman, Julia E.; Kuivila, Kathryn; Nowell, Lisa H.

2012-01-01

The U.S. Geological Survey (USGS) has a periodic need to re-evaluate pesticide compounds in terms of priorities for inclusion in monitoring and studies and, thus, must also assess the current analytical capabilities for pesticide detection. To meet this need, a strategy has been developed to prioritize pesticides and degradates for analytical methods development. Screening procedures were developed to separately prioritize pesticide compounds in water and sediment. The procedures evaluate pesticide compounds in existing USGS analytical methods for water and sediment and compounds for which recent agricultural-use information was available. Measured occurrence (detection frequency and concentrations) in water and sediment, predicted concentrations in water and predicted likelihood of occurrence in sediment, potential toxicity to aquatic life or humans, and priorities of other agencies or organizations, regulatory or otherwise, were considered. Several existing strategies for prioritizing chemicals for various purposes were reviewed, including those that identify and prioritize persistent, bioaccumulative, and toxic compounds, and those that determine candidates for future regulation of drinking-water contaminants. The systematic procedures developed and used in this study rely on concepts common to many previously established strategies. The evaluation of pesticide compounds resulted in the classification of compounds into three groups: Tier 1 for high priority compounds, Tier 2 for moderate priority compounds, and Tier 3 for low priority compounds. For water, a total of 247 pesticide compounds were classified as Tier 1 and, thus, are high priority for inclusion in analytical methods for monitoring and studies. Of these, about three-quarters are included in some USGS analytical method; however, many of these compounds are included on research methods that are expensive and for which there are few data on environmental samples. The remaining quarter of Tier 1 compounds are high priority as new analytes. The objective for analytical methods development is to design an integrated analytical strategy that includes as many of the Tier 1 pesticide compounds as possible in a relatively few, cost-effective methods. More than 60 percent of the Tier 1 compounds are high priority because they are anticipated to be present at concentrations approaching levels that could be of concern to human health or aquatic life in surface water or groundwater. An additional 17 percent of Tier 1 compounds were frequently detected in monitoring studies, but either were not measured at levels potentially relevant to humans or aquatic organisms, or do not have benchmarks available with which to compare concentrations. The remaining 21 percent are pesticide degradates that were included because their parent pesticides were in Tier 1. Tier 1 pesticide compounds for water span all major pesticide use groups and a diverse range of chemical classes, with herbicides and their degradates composing half of compounds. Many of the high priority pesticide compounds also are in several national regulatory programs for water, including those that are regulated in drinking water by the U.S. Environmental Protection Agency under the Safe Drinking Water Act and those that are on the latest Contaminant Candidate List. For sediment, a total of 175 pesticide compounds were classified as Tier 1 and, thus, are high priority for inclusion in analytical methods available for monitoring and studies. More than 60 percent of these compounds are included in some USGS analytical method; however, some are spread across several research methods that are expensive to perform, and monitoring data are not extensive for many compounds. The remaining Tier 1 compounds for sediment are high priority as new analytes. The objective for analytical methods development for sediment is to enhance an existing analytical method that currently includes nearly half of the pesticide compounds in Tier 1 by adding as many additional Tier 1 compounds as are analytically compatible. About 35 percent of the Tier 1 compounds for sediment are high priority on the basis of measured occurrence. A total of 74 compounds, or 42 percent, are high priority on the basis of predicted likelihood of occurrence according to physical-chemical properties, and either have potential toxicity to aquatic life, high pesticide useage, or both. The remaining 22 percent of Tier 1 pesticide compounds were either degradates of Tier 1 parent compounds or included for other reasons. As with water, the Tier 1 pesticide compounds for sediment are distributed across the major pesticide-use groups; insecticides and their degradates are the largest fraction, making up 45 percent of Tier 1. In contrast to water, organochlorines, at 17 percent, are the largest chemical class for Tier 1 in sediment, which is to be expected because there is continued widespread detection in sediments of persistent organochlorine pesticides and their degradates at concentrations high enough for potential effects on aquatic life. Compared to water, there are fewer available benchmarks with which to compare contaminant concentrations in sediment, but a total of 19 Tier 1 compounds have at least one sediment benchmark or screening value for aquatic organisms. Of the 175 compounds in Tier 1, 77 percent have high aquatic-life toxicity, as defined for this process. This evaluation of pesticides and degradates resulted in two lists of compounds that are priorities for USGS analytical methods development, one for water and one for sediment. These lists will be used as the basis for redesigning and enhancing USGS analytical capabilities for pesticides in order to capture as many high-priority pesticide compounds as possible using an economically feasible approach.

Perfluorinated Compounds in Fish from U.S. Urban Rivers and the Great Lakes

EPA Science Inventory

Perfluorinated compounds (PFCs) have recently received scientific and regulatory attention due to their broad environmental distribution, persistence, bioaccumulative potential, and toxicity. Some studies suggest that the consumption of fish from contaminated waters may be a maj...

Identification of new drug candidates against Borrelia burgdorferi using high-throughput screening.

PubMed

Pothineni, Venkata Raveendra; Wagh, Dhananjay; Babar, Mustafeez Mujtaba; Inayathullah, Mohammed; Solow-Cordero, David; Kim, Kwang-Min; Samineni, Aneesh V; Parekh, Mansi B; Tayebi, Lobat; Rajadas, Jayakumar

2016-01-01

Lyme disease is the most common zoonotic bacterial disease in North America. It is estimated that >300,000 cases per annum are reported in USA alone. A total of 10%-20% of patients who have been treated with antibiotic therapy report the recrudescence of symptoms, such as muscle and joint pain, psychosocial and cognitive difficulties, and generalized fatigue. This condition is referred to as posttreatment Lyme disease syndrome. While there is no evidence for the presence of viable infectious organisms in individuals with posttreatment Lyme disease syndrome, some researchers found surviving Borrelia burgdorferi population in rodents and primates even after antibiotic treatment. Although such observations need more ratification, there is unmet need for developing the therapeutic agents that focus on removing the persisting bacterial form of B. burgdorferi in rodent and nonhuman primates. For this purpose, high-throughput screening was done using BacTiter-Glo assay for four compound libraries to identify candidates that stop the growth of B. burgdorferi in vitro. The four chemical libraries containing 4,366 compounds (80% Food and Drug Administration [FDA] approved) that were screened are Library of Pharmacologically Active Compounds (LOPAC1280), the National Institutes of Health Clinical Collection, the Microsource Spectrum, and the Biomol FDA. We subsequently identified 150 unique compounds, which inhibited >90% of B. burgdorferi growth at a concentration of <25 µM. These 150 unique compounds comprise many safe antibiotics, chemical compounds, and also small molecules from plant sources. Of the 150 unique compounds, 101 compounds are FDA approved. We selected the top 20 FDA-approved molecules based on safety and potency and studied their minimum inhibitory concentration and minimum bactericidal concentration. The promising safe FDA-approved candidates that show low minimum inhibitory concentration and minimum bactericidal concentration values can be chosen as lead molecules for further advanced studies.

Advanced oxidation process-mediated removal of pharmaceuticals from water: A review.

PubMed

Kanakaraju, Devagi; Glass, Beverley D; Oelgemöller, Michael

2018-08-01

Pharmaceuticals, which are frequently detected in natural and wastewater bodies as well as drinking water have attracted considerable attention, because they do not readily biodegrade and may persist and remain toxic. As a result, pharmaceutical residues pose on-going and potential health and environmental risks. To tackle these emerging contaminants, advanced oxidation processes (AOPs) such as photo-Fenton, sonolysis, electrochemical oxidation, radiation and ozonation etc. have been applied to remove pharmaceuticals. These processes utilize the high reactivity of hydroxyl radicals to progressively oxidize organic compounds to innocuous products. This review provides an overview of the findings from recent studies, which have applied AOPs to degrade pharmaceutical compounds. Included is a discussion that links various factors of TiO 2 -mediated photocatalytic treatment to its effectiveness in degrading pharmaceutical residues. This review furthermore highlights the success of AOPs in the removal of pharmaceuticals from different water matrices and recommendations for future studies are outlined. Copyright © 2018 Elsevier Ltd. All rights reserved.

Nitrapyrin in streams: The first study documenting off-field transport of a nitrogen stabilizer compound

USGS Publications Warehouse

Woodward, Emily; Hladik, Michelle; Kolpin, Dana W.

2016-01-01

Nitrapyrin is a bactericide that is co-applied with fertilizer to prevent nitrification and enhance corn yields. While there have been studies of the environmental fate of nitrapyrin, there is no documentation of its off-field transport to streams. In 2016, 59 water samples from 11 streams across Iowa were analyzed for nitrapyrin and its degradate, 6-chloropicolinic acid (6-CPA), along with three widely used herbicides, acetochlor, atrazine, and metolachlor. Nitrapyrin was detected in seven streams (39% of water samples) with concentrations ranging from 12 to 240 ng/L; 6-CPA was never detected. The herbicides were ubiquitously detected (100% of samples, 28–16000 ng/L). Higher nitrapyrin concentrations in streams were associated with rainfall events following spring fertilizer applications. Nitrapyrin persisted in streams for up to 5 weeks. These results highlight the need for more research focused on the environmental fate and transport of nitrapyrin and the potential toxicity this compound could have on nontarget organisms.

Triclosan: Current Status, Occurrence, Environmental Risks and Bioaccumulation Potential

PubMed Central

Dhillon, Gurpreet Singh; Kaur, Surinder; Pulicharla, Rama; Brar, Satinder Kaur; Cledón, Maximiliano; Verma, Mausam; Surampalli, Rao Y.

2015-01-01

Triclosan (TCS) is a multi-purpose antimicrobial agent used as a common ingredient in everyday household personal care and consumer products. The expanded use of TCS provides a number of pathways for the compound to enter the environment and it has been detected in sewage treatment plant effluents; surface; ground and drinking water. The physico-chemical properties indicate the bioaccumulation and persistence potential of TCS in the environment. Hence, there is an increasing concern about the presence of TCS in the environment and its potential negative effects on human and animal health. Nevertheless, scarce monitoring data could be one reason for not prioritizing TCS as emerging contaminant. Conventional water and wastewater treatment processes are unable to completely remove the TCS and even form toxic intermediates. Considering the worldwide application of personal care products containing TCS and inefficient removal and its toxic effects on aquatic organisms, the compound should be considered on the priority list of emerging contaminants and its utilization in all products should be regulated. PMID:26006133

Hospitals and plastics. Dioxin prevention and medical waste incinerators.

PubMed

Thornton, J; McCally, M; Orris, P; Weinberg, J

1996-01-01

CHLORINATED DIOXINS and related compounds are extremely potent toxic substances, producing effects in humans and animals at extremely low doses. Because these compounds are persistent in the environment and accumulate in the food chain, they are now distributed globally, and every member of the human population is exposed to them, primarily through the food supply and mothers' milk. An emerging body of information suggests that dioxin contamination has reached a level that may pose a large-scale, long-term public health risk. Of particular concern are dioxin's effects on reproduction, development, immune system function, and carcinogenesis. Medical waste incineration is a major source of dioxins. Polyvinyl chloride (PVC) plastic, as the dominant source of organically bound chlorine in the medical waste stream, is the primary cause of "iatrogenic" dioxin produced by the incineration of medical wastes. Health professionals have a responsibility to work to reduce dioxin exposure from medical sources. Health care institutions should implement policies to reduce the use of PVC plastics, thus achieving major reductions in medically related dioxin formation.

Brominated flame retardants (BFRs) in eggs from birds of prey from Southern Germany, 2014.

PubMed

Vetter, Walter; Gallistl, Christoph; Schlienz, Annika; Preston, Theresa; Müller, Jens; von der Trenck, K Theo

2017-12-01

In Southern Germany, peregrine falcons (Falco peregrinus), which almost exclusively prey on other birds, are top predators of the terrestrial food chain. These animals accumulate persistent organic pollutants (POPs) and halogenated flame retardants (HFRs) with mothers transferring these lipophilic contaminants to their eggs. Here we analyzed unhatched eggs of eleven peregrine falcons and six of other species, and report concentrations of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), hexabromobenzene (HBB), 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and its metabolites, pentabromoethylbenzene (PBEB), pentabromotoluene (PBT), and tribromophenol (TBP). The extract of one purified peregrine falcon egg sample was comprehensively analyzed in a non-target (NT) approach by gas chromatography with mass spectrometry in the electron capture negative ion mode. A total of ∼400 polyhalogenated compounds were detected, among them dechloranes and possibly transformation products, two tetrabrominated metabolites of PBT and several compounds unknown to us which could not be identified. Copyright © 2017 Elsevier Ltd. All rights reserved.

Organic compounds in produced waters from coalbed natural gas wells in the Powder River Basin, Wyoming, USA

USGS Publications Warehouse

Orem, W.H.; Tatu, C.A.; Lerch, H.E.; Rice, C.A.; Bartos, T.T.; Bates, A.L.; Tewalt, S.; Corum, M.D.

2007-01-01

The organic composition of produced water samples from coalbed natural gas (CBNG) wells in the Powder River Basin, WY, sampled in 2001 and 2002 are reported as part of a larger study of the potential health and environmental effects of organic compounds derived from coal. The quality of CBNG produced waters is a potential environmental concern and disposal problem for CBNG producers, and no previous studies of organic compounds in CBNG produced water have been published. Organic compounds identified in the produced water samples included: phenols, biphenyls, N-, O-, and S-containing heterocyclic compounds, polycyclic aromatic hydrocarbons (PAHs), aromatic amines, various non-aromatic compounds, and phthalates. Many of the identified organic compounds (phenols, heterocyclic compounds, PAHs) are probably coal-derived. PAHs represented the group of organic compounds most commonly observed. Concentrations of total PAHs ranged up to 23 ??g/L. Concentrations of individual compounds ranged from about 18 to <0.01 ??g/L. Temporal variability of organic compound concentrations was documented, as two wells with relatively high organic compound contents in produced water in 2001 had much lower concentrations in 2002. In many areas, including the PRB, coal strata provide aquifers for drinking water wells. Organic compounds observed in produced water are also likely present in drinking water supplied from wells in the coal. Some of the organic compounds identified in the produced water samples are potentially toxic, but at the levels measured in these samples are unlikely to have acute health effects. The human health effects of low-level, chronic exposure to coal-derived organic compounds in drinking water are currently unknown. Continuing studies will evaluate possible toxic effects from low level, chronic exposure to coal-derived organic compounds in drinking water supplies.

Occurrence, distribution, and seasonality of emerging contaminants in urban watersheds.

PubMed

Bai, Xuelian; Lutz, Alex; Carroll, Rosemary; Keteles, Kristen; Dahlin, Kenneth; Murphy, Mark; Nguyen, David

2018-06-01

The widespread occurrence of natural and synthetic organic chemicals in surface waters can cause ecological risks and human health concerns. This study measured a suite of contaminants of emerging concern (CECs) in water samples collected by the U.S. Environmental Protection Agency Region 8 around the Denver, Colorado, metropolitan area. The results showed that 109 of 144 analyzed pharmaceutical compounds, 42 of 55 analyzed waste-indicator compounds (e.g., flame retardants, hormones, and personal care products), and 39 of 72 analyzed pesticides were detected in the water samples collected monthly between April and November in both 2014 and 2015. Pharmaceutical compounds were most abundant in the surface waters and their median concentrations were measured up to a few hundred nanograms per liter. The CEC concentrations varied depending on sampling locations and seasons. The primary source of CECs was speculated to be wastewater effluent. The CEC concentrations were correlated to streamflow volume and showed significant seasonal effects. The CECs were less persistent during spring runoff season compared with baseflow season at most sampling sites. These results are useful for providing baseline data for surface CEC monitoring and assessing the environmental risks and potential human exposure to CECs. Copyright © 2018 Elsevier Ltd. All rights reserved.

An Overview of the Effects of Dioxins and Dioxin-like Compounds on Vertebrates, as Documented in Human and Ecological Epidemiology

PubMed Central

White, Sally S.; Birnbaum, Linda S.

2009-01-01

Dioxins and dioxin-like compounds are primary examples of persistent organic pollutants that induce toxicity in both wildlife and humans. Over the past 200 years these compounds have been almost exclusively generated by human activity and have left a string of disasters in the wake of their accidental release. Most recently, the contamination of the Irish pork supply with dioxins resulted in an international recall of all Irish pork products. Epidemiologic data on human and ecological dioxin exposures have revealed a common pattern of biological response among vertebrate species, which is mediated through activation of the Aryl hydrocarbon Receptor (AhR). These AhR-mediated effects include profound consequences on the vertebrate individual exposed in early-life, with respect to myriad developmental endpoints including neurologic, immunologic, and reproductive parameters. Humans appear to be susceptible to these effects, in a manner similar to that of the laboratory and wildlife species which have demonstrated such outcomes. Furthermore, epidemiologic data suggest that there is little or no margin of exposure for humans, with respect to these developmental effects. Given these concerns, prudent public health policy should include the continued reduction of exposures. PMID:19953395

Long-Term Exposure of Tropical Soils to Pressure Treated Lumber, Barro Colorado Island, Panama: Impacts on Soil Metal Mobility and Microbial Community Structure

NASA Astrophysics Data System (ADS)

Marietta, M. L.; Fowle, D. A.; Roberts, J. A.

2008-12-01

Pressure treated lumber (CCA) has been used in a variety of structures for over seven decades, but recent concerns have been raised about leaching of metals such as chromium (Cr) and arsenic (As) into proximal soils and water supplies. Pressure treated lumber abundance and its continued use necessitate a thorough understanding of metal release and sequestration in the subsurface. To date, no long-term, in situ study on the migration of CCA compounds from lumber has been performed. Barro Colorado Island, Panama is the site of several previous CCA studies and provides an opportunity to investigate the long-term (>70 years) effects of pressure treated lumber in oxisols, where high rainfall and warm temperatures may represent an end-member condition for the leaching and mobility of these metals. Soil samples from CCA and control sites were measured for Cr, As, Cu, Zn, and Fe abundances, microbial biomass and community structure via phospholipid fatty acid analysis, along with basic soil properties. CCA lumber samples were also characterized for their metal abundance. Lumber treated with zinc meta-arsenite displayed advanced decay with elevated As, Cu, and Zn concentrations observed in the adjacent soil. Increased soil organic matter and microbial biomass correlate to decreases in Fe and Fe-associated metals compared to the control. High As concentrations persist to <1 m of the source. Lumber treated with potassium dichromate contained high chromium concentrations and displayed little decay, however, soil concentrations of Cr, Fe, and Cu were generally less than control soils. Over these same intervals, soil organic matter and microbial biomass increased, particularly the fraction of metal reducing bacteria (MRB). We hypothesize that organic carbon loading from lumber stimulates MRB, leading to mobilization of Fe and Fe-associated metals from these oxide-rich soils. Principal component analysis of PLFA data confirms a distinction between controls and samples with elevated metal abundance at each site. This study provides fundamental insight into the long-term persistence of CCA compounds in Fe-rich soils and could serve in practical applications related to CCA contamination.

Chemical evolution of gaseous air pollutants down-wind of tropical megacities: Mexico City case study

NASA Astrophysics Data System (ADS)

Madronich, Sasha

The photochemical evolution of a polluted air parcel originating in a tropical megacity was modeled for 3 days using a box model with detailed gas-phase chemistry. The parcel was initialized with concentrations typically observed in Mexico City for nitrogen oxides (80 parts per billion on a molar basis, or ppbv), carbon monoxide (3000 ppbv), non-methane hydrocarbons (1700 ppb on a carbon basis, or ppbC) and formaldehyde (23.9 ppbv). Vigorous ozone production occurred during day 1, followed by gradual net destruction during the next 2 days. Other major inorganic products were nitric acid and hydrogen peroxide (35 and 16 ppbv, respectively at the end of day 3), while organic products included ketones (83 ppbv), organic hydroperoxides (25 ppbv), peroxyacyl nitrates (28 ppbv), aldehydes (18 ppbv), organic acids (16 ppbv), alkyl nitrates (10 ppbv) and alcohols (0.2 ppbv). Also produced was multitude of different polyfunctional compounds, present individually at small concentrations, but with significant summed concentrations (68, 49 and 1.5 ppbC, respectively, for compounds having 2, 3 or 4 functional groups), which could contribute to the formation of secondary aerosols. The overall reactivity of the parcel (daytime concentrations of hydroxy, hydroperoxy and organic peroxy radicals; and cumulative hydroxyl radical loss rates) remained relatively constant and high on days 2 and 3. This persistent gas-phase reactivity suggests that urban areas could affect regional and global tropospheric chemistry. However, it remains unclear whether heterogeneous losses, on aerosol particles, reduce this reactivity while simultaneously changing aerosol chemical, microphysical and radiative properties relevant to weather and climate.

Behavioral self-organization underlies the resilience of a coastal ecosystem.

PubMed

de Paoli, Hélène; van der Heide, Tjisse; van den Berg, Aniek; Silliman, Brian R; Herman, Peter M J; van de Koppel, Johan

2017-07-25

Self-organized spatial patterns occur in many terrestrial, aquatic, and marine ecosystems. Theoretical models and observational studies suggest self-organization, the formation of patterns due to ecological interactions, is critical for enhanced ecosystem resilience. However, experimental tests of this cross-ecosystem theory are lacking. In this study, we experimentally test the hypothesis that self-organized pattern formation improves the persistence of mussel beds ( Mytilus edulis ) on intertidal flats. In natural beds, mussels generate self-organized patterns at two different spatial scales: regularly spaced clusters of mussels at centimeter scale driven by behavioral aggregation and large-scale, regularly spaced bands at meter scale driven by ecological feedback mechanisms. To test for the relative importance of these two spatial scales of self-organization on mussel bed persistence, we conducted field manipulations in which we factorially constructed small-scale and/or large-scale patterns. Our results revealed that both forms of self-organization enhanced the persistence of the constructed mussel beds in comparison to nonorganized beds. Small-scale, behaviorally driven cluster patterns were found to be crucial for persistence, and thus resistance to wave disturbance, whereas large-scale, self-organized patterns facilitated reformation of small-scale patterns if mussels were dislodged. This study provides experimental evidence that self-organization can be paramount to enhancing ecosystem persistence. We conclude that ecosystems with self-organized spatial patterns are likely to benefit greatly from conservation and restoration actions that use the emergent effects of self-organization to increase ecosystem resistance to disturbance.

Behavioral self-organization underlies the resilience of a coastal ecosystem

PubMed Central

de Paoli, Hélène; van der Heide, Tjisse; van den Berg, Aniek; Silliman, Brian R.; Herman, Peter M. J.

2017-01-01

Self-organized spatial patterns occur in many terrestrial, aquatic, and marine ecosystems. Theoretical models and observational studies suggest self-organization, the formation of patterns due to ecological interactions, is critical for enhanced ecosystem resilience. However, experimental tests of this cross-ecosystem theory are lacking. In this study, we experimentally test the hypothesis that self-organized pattern formation improves the persistence of mussel beds (Mytilus edulis) on intertidal flats. In natural beds, mussels generate self-organized patterns at two different spatial scales: regularly spaced clusters of mussels at centimeter scale driven by behavioral aggregation and large-scale, regularly spaced bands at meter scale driven by ecological feedback mechanisms. To test for the relative importance of these two spatial scales of self-organization on mussel bed persistence, we conducted field manipulations in which we factorially constructed small-scale and/or large-scale patterns. Our results revealed that both forms of self-organization enhanced the persistence of the constructed mussel beds in comparison to nonorganized beds. Small-scale, behaviorally driven cluster patterns were found to be crucial for persistence, and thus resistance to wave disturbance, whereas large-scale, self-organized patterns facilitated reformation of small-scale patterns if mussels were dislodged. This study provides experimental evidence that self-organization can be paramount to enhancing ecosystem persistence. We conclude that ecosystems with self-organized spatial patterns are likely to benefit greatly from conservation and restoration actions that use the emergent effects of self-organization to increase ecosystem resistance to disturbance. PMID:28696313

Local impacts, global sources: The governance of boundary-crossing chemicals.

PubMed

Gorman, Hugh S; Gagnon, Valoree S; Norman, Emma S

2016-12-01

Over the last half century, a multijurisdictional, multiscale system of governance has emerged to address concerns associated with toxic chemicals that have the capacity to bioaccumulate in organisms and biomagnify in food chains, leading to fish consumption advisories. Components of this system of governance include international conventions (such as the Stockholm Convention on Persistent Organic Pollutants and the Minamata Convention on Mercury), laws enacted by nation states and their subjurisdictions, and efforts to adaptively manage regional ecosystems (such as the U.S.-Canadian Great Lakes). Given that many of these compounds - including mercury, industrial chemicals such as polychlorinated biphenyls, and pesticides such as toxaphene - circulate throughout the globe through cycles of deposition and reemission, regional efforts to eliminate the need for fish consumption advisories cannot be successful without efforts to reduce emissions everywhere in the world. This paper argues that the scientific community, by monitoring the concentrations of these compounds in the atmosphere and by modeling their fate and transport, play an important role in connecting the various jurisdictional scales of governance. In addition, the monitoring networks that this community of scientists has established can be visualized as a technology of governance essential in an era in which societies have the capacity to produce and release such chemicals on an industrial scale.

Occurrence and distribution of organochlorine compounds in sediment and livers of striped bass (Morone saxatilis) from the San Francisco Bay-Delta Estuary

USGS Publications Warehouse

Pereira, W.E.; Hostettler, F.D.; Cashman, J.R.; Nishioka, R.S.

1994-01-01

A preliminary assessment was made in 1992 of chlorinated organic compounds in sediments and in livers of striped bass from the San Francisco Bay-Delta Estuary. Samples of sediment and striped bass livers contained DDT (ethane, 1,1,1-trichloro-2,2-bis (p-chlorophenyl)-) and its degradation products, DDD (ethane, 1,1-dichloro-2,2-bis(p-chlorophenyl)-) and DDE (ethylene, 1,1-dichloro-2,2-bis (p-chlorophenyl)-); PCBs (polychlorinated biphenyls); alpha and gamma chlordane, and cis and trans nonachlor. In addition, the livers of striped bass contained small concentrations of DCPA (dimethyl tetrachloroterephthalate), a pre-emergent herbicide. Agricultural run-off from the Sacramento and San Joaquin Rivers, as well as atmospheric deposition, are probably responsible for a low chronic background of DDT in sediments throughout San Francisco Bay. Larger concentrations of DDT in sediment near Richmond in the Central Bay, and Coyote Creek in the South Bay may be derived from point sources. Ratios of pentachloro isomers of PCBs to hexachloro isomers in the South Bay sediments were different from those in the Central and North Bay, suggesting either differences in microbial activity in the sediments or different source inputs of PCBs. Concentrations of alpha chlordane in livers of striped bass were greater than those of gamma chlordane, which suggests a greater environmental stability and persistence of alpha chlordane. Trans nonachlor, a minor component of technical chlorodane, was present in greater concentrations than alpha and gamma chlordane and cis nonachlor. Trans nonachlor is more resistant to metabolism than alpha and gamma chlordane and cis nonachlor, and serves as an environmentally stable marker compound of chlordane contamination in the estuary. Chlorinated organic compounds have bioaccumulated in the livers of striped bass. These compounds may contribute to the decline of the striped bass in San Francisco Bay-Delta Estuary.

Fate and Transport of Organic Contaminants in Coastal Marsh Sediments Resulting from the 2010 Gulf Oil Spill

NASA Astrophysics Data System (ADS)

Natter, M.; Keevan, J.; Lee, M.; Keimowitz, A.; Savrda, C.; Son, A.; Okeke, B.; Wang, Y.

2011-12-01

The devastating explosion and subsequent sinking of the oil platform Deepwater Horizon at the British Petroleum Macondo-1 well in the Northern Gulf of Mexico on April 20, 2010, released approximately 4.9 million barrels of crude oil into the Gulf before the well was capped on July 15, 2010. Although most light compounds of oil may be easily degraded by natural microbes on the short term, saturated heavy oil (e.g., asphaltenes, resins, polycyclic aromatics, etc.) and those adsorbed by sediments could persist in the environment for decades. The long-term effects of high levels of persistent oil compounds on biogeochemical evolution and ecosystems of salt marshes remain unclear. This research investigates the spatial range and changes in levels of oil and their biogeochemical impacts. A total of ten marsh sampling sites that varied from pristine, non-effected marshes (e.g., Weeks Bay and Wolf Bay, Alabama) to heavily oiled wetlands (e.g., Bay Jimmy and Bayou Dulac, Louisiana) were utilized for this study. Sediment cores, bulk sediments, surface water samples, degraded oil, oiled dead marsh grass, and live marsh grass were collected from these sites in an attempt to study the source, distribution, and evolution of organic compounds and oil present in sediments and pore-waters. Geochemical analyses show alarmingly high organic carbon loads in pore-waters and sediments at heavily contaminated sites months after the influx of oil ceased. Very high levels (10-28%) of total organic carbon (TOC) within the heavily oiled sediments (down to 30 cm) are clearly distinguished from those found in pristine wetland sediments (generally < 5%). TOC levels are elevated in the deeper sediments while being depleated in the uppermost ones at certain locations. The TOC contents in uppermost sediments may be reduced by microbial degradation, water mixing, and the use of oil dispersants. Furthermore, dissolved organic carbon (DOC) levels of pore-waters extracted from oiled sediments, ranging up to hundreds of mg/kg, are on the order of one to two magnitudes higher than those at pristine and slightly contaminated sites. These DOC levels also interestingly increase with depth, possibly indicating saltwater-freshwater mixing near the sediment surface or freshwater recharge from rainfall. The spatial changes in DOC indicate that seawater and oil invaded along the deeper portion of the marsh sediments due to their higher density with respect to freshwater. TOC and DOC data clearly indicate that not all the spilled oil rose to the water surface and washed on-shore. Plumes of partially degraded oil could be spreading at various levels of the water column and feeding the underlying sediments. Geochemical biomarkers and stable isotopes (carbon and nitrogen) analyses of wetland plants, oiled sediments, and initial crude oils are underway to trace the sources of oil and the extent of oil degradation in impacted wetlands.

Occurrence and fate of the angiotensin II receptor antagonist transformation product valsartan acid in the water cycle--a comparative study with selected β-blockers and the persistent anthropogenic wastewater indicators carbamazepine and acesulfame.

PubMed

Nödler, Karsten; Hillebrand, Olav; Idzik, Krzysztof; Strathmann, Martin; Schiperski, Ferry; Zirlewagen, Johannes; Licha, Tobias

2013-11-01

The substantial transformation of the angiotensin II receptor antagonist valsartan to the transformation product 2'-(2H-tetrazol-5-yl)-[1,1'-biphenyl]-4-carboxylic acid (referred to as valsartan acid) during the activated sludge process was demonstrated in the literature and confirmed in the here presented study. However, there was a severe lack of knowledge regarding the occurrence and fate of this compound in surface water and its behavior during drinking water treatment. In this work a comparative study on the occurrence and persistency of valsartan acid, three frequently used β-blockers (metoprolol, atenolol, and sotalol), atenolol acid (one significant transformation product of atenolol and metoprolol), and the two widely distributed persistent anthropogenic wastewater indicators carbamazepine and acesulfame in raw sewage, treated wastewater, surface water, groundwater, and tap water is presented. Median concentrations of valsartan acid in the analyzed matrices were 101, 1,310, 69, <1.0, and 65 ng L(-1), respectively. Treated effluents from wastewater treatment plants were confirmed as significant source. Regarding concentration levels of pharmaceutical residues in surface waters valsartan acid was found just as relevant as the analyzed β-blockers and the anticonvulsant carbamazepine. Regarding its persistency in surface waters it was comparable to carbamazepine and acesulfame. Furthermore, removal of valsartan acid during bank filtration was poor, which demonstrated the relevance of this compound for drinking water suppliers. Regarding drinking water treatment (Muelheim Process) the compound was resistant to ozonation but effectively eliminated (≥90%) by subsequent activated carbon filtration. However, without applying activated carbon filtration the compound may enter the drinking water distribution system as it was demonstrated for Berlin tap water. Copyright © 2013 Elsevier Ltd. All rights reserved.

Biogenic volatile organic compounds - small is beautiful

NASA Astrophysics Data System (ADS)

Owen, S. M.; Asensio, D.; Li, Q.; Penuelas, J.

2012-12-01

While canopy and regional scale flux measurements of biogenic volatile organic compounds (bVOCs) are essential to obtain an integrated picture of total compound reaching the atmosphere, many fascinating and important emission details are waiting to be discovered at smaller scales, in different ecological and functional compartments. We concentrate on bVOCs below ground to <2m above ground level. Emissions at leaf scale are well documented and widely presented, and are not discussed here. Instead we describe some details of recent research on rhizosphere bVOCs, and bVOCs associated with pollination of flowers. Although bVOC emissions from soil surfaces are small, bVOCs are exuded by roots of some plant species, and can be extracted from decaying litter. Naturally occurring monoterpenes in the rhizosphere provide a specialised carbon source for micro-organisms, helping to define the micro-organism community structure, and impacting on nutrient cycles which are partly controlled by microorganisms. Naturally occurring monoterpenes in the soil system could also affect the aboveground structure of ecosystems because of their role in plant defence strategies and as mediating chemicals in allelopathy. A gradient of monoterpene concentration was found in soil around Pinus sylvestris and Pinus halepensis, decreasing with distance from the tree. Some compounds (α-pinene, sabinene, humulene and caryophyllene) in mineral soil were linearly correlated with the total amount of each compound in the overlying litter, indicating that litter might be the dominant source of these compounds. However, α-pinene did not fall within the correlation, indicating a source other than litter, probably root exudates. We also show that rhizosphere bVOCs can be a carbon source for soil microbes. In a horizontal gradient from Populus tremula trees, microbes closest to the tree trunk were better enzymatically equipped to metabolise labeled monoterpene substrate. Monoterpenes can also increase the degradation rate in soil of the persistant organic pollutants, likely acting as analogues for the cometabo-lism of polychlorinated biphenyls (PCBs) Flowers of a ginger species (Alpinia kwangsiensis) and a fig species (Ficus hispida) showed different bVOC signals pre- and post pollination. For Ficus hispida, there are three floral stages of a fig-wasp dependency mechanism: receptive, post pollinator and interfloral. Of 28 compounds detected, transcaryophyllene with trans-β-farnesene were the most important at the receptor stage, trans-caryophyllene was the most abundant at the post-pollinator stage, and isoprene was the most abundant in the interfloral stage. Alpinia kwangsiensis presents two morphologies for the reproductive parts of the flower. The "anaflexistyle" morphology has the flower style lowered in the morning and raised in the afternoon. This is reversed for the "cataflexistyle" morphology. The bVOC mixture emitted by each morphology in morning and afternoon was complex. However for compounds showing a difference (cis-ocimene and Z + E epoxy -ocimene), the emissions from the anaflexistyle were greater than from the cataflexistyle, and were greater in the afternoon compared with the morning emissions. Where large flowering plant species are abundant, big changes in monoterpene emissions at < 2m above ground level over relatively small periods of time during pollination are likely to be missed in larger scale integrated flux measurements.

MAMMALIAN METABOLISM AND DISTRIBUTION OF PERFLUOROOCTYL ETHANOL (8-2 TELOMER ALCOHOL) AND ITS OXIDATION METABOLITES

EPA Science Inventory

Perfluorinated compounds have been shown to be globally distributed, bioaccumulative, persistent and potentially toxic. It has been hypothesized that many precursor fluorinated compounds, including the telomer alcohols, degrade or metabolize to the common metabolite PFOA.

Polychlorobiphenyl (PCB) metabolism by plant cells (journal version)

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

Fletcher, J.; Groeger, A.; McCrady, J.

1987-01-01

Suspension cultures of Paul's Scarlet rose provided with 0.3 ppm of 2,2',4,4'-tetrachlorobiphenyl metabolized the compound at a rate of 4.6 pmoles h g dry wt. The environmental and technological significance of plants to metabolize environmentally persistent compounds is discussed.

The astrobiology of Titan

NASA Astrophysics Data System (ADS)

Raulin, F.; Coll, P.; Cabane, M.; Hebrard, E.; Israel, G.; Nguyen, M.-J.; Szopa, C.; Gpcos Team

Largest satellite of Saturn and the only satellite in the solar system having a dense atmosphere, Titan is one of the key planetary bodies for astrobiological studies, due to several aspects: Its analogies with planet Earth, in spite of much lower temperatures, The Cassini-Huygens data have largely confirmed the many analogies between Titan and our own planet. Both have similar vertical temperature profiles, (although much colder, of course, on Titan). Both have condensable and non condensable greenhouse gases in their atmosphere. Both are geologically very active. Furthermore, the data also suggest strongly the presence of a methane cycle on Titan analogous to the water cycle on Earth. The presence of an active organic chemistry, involving several of the key compounds of prebiotic chemistry. The recent data obtained from the Huygens instruments show that the organic matter in Titan low atmosphere (stratosphere and troposphere) is mainly concentrated in the aerosol particles. Because of the vertical temperature profile in this part of the atmosphere, most of the volatile organics are probably mainly condensed on the aerosol particles. The nucleus of these particles seems to be made of complex macromolecular organic matter, well mimicked in the laboratory by the "Titan's tholins". Now, laboratory tholins are known to release many organic compounds of biological interest, such as amino acids and purine and pyrimidine bases, when they are in contact with liquid water. Such hydrolysis may have occurred on the surface of Titan, in the bodies of liquid water which episodically may form on Titan's surface from meteoritic and cometary impacts. The formation of biologically interesting compounds may also occur in the deep water ocean, from the hydrolysis of complex organic material included in the chrondritic matter accreted during the formation of Titan. The possible emergence and persistence of Life on Titan 1 All ingredients which seems necessary for Life are present on Titan : • liquid water : permanently as a deep sub-surface ocean, and even episodically on the surface, • organic matter : in the internal structure, from chondritic materials, and in the atmosphere and on the surface, from the atmospheric organic chemistry • and energy : in the atmosphere (solar UV photons, energetic electrons from Saturn magnetosphere and cosmic rays) and, probably, in the environment of the sub-surface ocean (radioactive nuclei in the deep interior and tidal energy dissipation) as also supported by the likely presence of cryovolcanism on the surface Thus, it cannot be excluded that life may have emerged on or in Titan. In spite of the extreme conditions in this environment life may have been able to adapt and to persist. Many data are still expected from the Cassini-Huygens mission and future astrobiological exploration mission of Titan are now under consideration. Nevertheless, Titan already looks like another word, with an active prebiotic-like chemistry, but in the absence of permanent liquid water, on the surface: a natural laboratory for prebiotic-like chemistry. References. Fortes, A.D. (2000), `Exobiological implications of a possible ammonia-water ocean inside Titan', Icarus 146, 444-452 Raulin, F. (2005), `Exo-Astrobiological Aspects of Europa and Titan: From Observations to Speculations', Space Science Review 116 (1-2), 471-496. Nature, (2005), `The Huygens probe on Titan', 8 News & Views, Articles and Letters 438, 756-802 Schulze-Makuch, D., and Grinspoon D.H. (2005), `Biologically enhanced energy and carbon cycling on Titan?',Astrobiology 5, 560-567. 2

Scavenging amphipods: sentinels for penetration of mercury and persistent organic chemicals into food webs of the deep Arctic Ocean.

PubMed

Bidleman, Terry F; Stern, Gary A; Tomy, Gregg T; Hargrave, Barry T; Jantunen, Liisa M; Macdonald, Robie W

2013-06-04

Archived specimens of the scavenging amphipod Eurythenes gryllus, collected from 2075 to 4250 m below the surface on five expeditions to the western and central Arctic Ocean between 1983 and 1998, were analyzed for total mercury (∑Hg), methyl mercury (MeHg), polychlorinated biphenyls (PCBs) and other industrial or byproduct organochlorines (chlorobenzenes, pentachloroanisole, octachlorostyrene), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs). Median ∑Hg concentrations ranged from 70 to 366 ng g(-1) wet weight (ww). MeHg concentrations (3.55 to 23.5 ng g(-1) ww) accounted for 1.7 to 20.1% (median 3.7%) of ∑Hg. ∑Hg and MeHg were positively and significantly correlated with ww (∑Hg r(2) = 0.18, p = 0.0004, n = 63; MeHg r(2) = 0.42, p = 0.0004, n = 25), but not significantly with δ(13)C nor δ(15)N. Median concentrations of total persistent organic pollutants (POPs) ranged from 9750 to 156,000 ng g(-1) lipid weight, with order of abundance: ∑TOX (chlorobornanes quantified as technical toxaphene) > ∑PCBs > ∑DDTs > ∑chlordanes > ∑mirex compounds > ∑BDEs ∼ ∑chlorobenzenes ∼ octachlorostyrene > α-hexachlorocyclohexane ∼ hexachlorobenzene ∼ pentachloroanisole. Enantioselective accumulation was found for the chiral OCPs o,p'-DDT, cis- and trans-chlordane, nonachlor MC6 and oxychlordane. Lipid-normalized POPs concentrations were elevated in amphipods with lipid percentages ≤10%, suggesting that utilization of lipids resulted in concentration of POPs in the remaining lipid pool. Multidimensional Scaling (MDS) analysis using log-transformed physiological variables and lipid-normalized organochlorine concentrations distinguished amphipods from the central vs western arctic stations. This distinction was also seen for PCB homologues, whereas profiles of other compound classes were more related to specific stations rather than central-west differences.

Highly chlorinated unintentionally produced persistent organic pollutants generated during the methanol-based production of chlorinated methanes: A case study in China.

PubMed

Zhang, Lifei; Yang, Wenlong; Zhang, Linli; Li, Xiaoxiu

2015-08-01

The formation of unintentionally produced persistent organic pollutants (POPs) may occur during various chlorination processes. In this study, emissions of unintentionally produced POPs during the methanol-based production of chlorinated methanes were investigated. High concentrations of highly chlorinated compounds such as decachlorobiphenyl, octachloronaphthalene, octachlorostyrene, hexachlorobutadiene, hexachlorocyclopentadiene, hexachlorobenzene, and pentachlorobenzene were found in the carbon tetrachloride byproduct of the methanol-based production of chlorinated methanes. The total emission amounts of hexachlorocyclopentadiene, hexachlorobutadiene, polychlorinated benzenes, polychlorinated naphthalenes, octachlorostyrene, and polychlorinated biphenyls released during the production of chlorinated methanes in China in 2010 were estimated to be 10080, 7350, 5210, 427, 212, and 167 kg, respectively. Moreover, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) were formed unintentionally during chlorinated methanes production, the emission factor for PCDDs/DFs was 364 μg toxic equivalency quotient (TEQ) t(-1) product for residues, which should be added into the UNEP toolkit for updating. It was worth noting that a high overall toxic equivalency quotient from polychlorinated naphthalenes and PCDDs/DFs was generated from the chlorinated methanes production in China in 2010. The values reached 563 and 32.8 g TEQ, respectively. The results of the study indicate that more research and improved management systems are needed to ensure that the methanol-based production of chlorinated methanes can be achieved safely. Copyright © 2015 Elsevier Ltd. All rights reserved.

A model of extracellular enzymes in free-living microbes: which strategy pays off?

PubMed

Traving, Sachia J; Thygesen, Uffe H; Riemann, Lasse; Stedmon, Colin A

2015-11-01

An initial modeling approach was applied to analyze how a single, nonmotile, free-living, heterotrophic bacterial cell may optimize the deployment of its extracellular enzymes. Free-living cells live in a dilute and complex substrate field, and to gain enough substrate, their extracellular enzymes must be utilized efficiently. The model revealed that surface-attached and free enzymes generate unique enzyme and substrate fields, and each deployment strategy has distinctive advantages. For a solitary cell, surface-attached enzymes are suggested to be the most cost-efficient strategy. This strategy entails potential substrates being reduced to very low concentrations. Free enzymes, on the other hand, generate a radically different substrate field, which suggests significant benefits for the strategy if free cells engage in social foraging or experience high substrate concentrations. Swimming has a slight positive effect for the attached-enzyme strategy, while the effect is negative for the free-enzyme strategy. The results of this study suggest that specific dissolved organic compounds in the ocean likely persist below a threshold concentration impervious to biological utilization. This could help explain the persistence and apparent refractory state of oceanic dissolved organic matter (DOM). Microbial extracellular enzyme strategies, therefore, have important implications for larger-scale processes, such as shaping the role of DOM in ocean carbon sequestration. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Synergistic cellular effects including mitochondrial destabilization, autophagy and apoptosis following low-level exposure to a mixture of lipophilic persistent organic pollutants.

PubMed

Rainey, Nathan E; Saric, Ana; Leberre, Alexandre; Dewailly, Etienne; Slomianny, Christian; Vial, Guillaume; Zeliger, Harold I; Petit, Patrice X

2017-07-05

Humans are exposed to multiple exogenous environmental pollutants. Many of these compounds are parts of mixtures that can exacerbate harmful effects of the individual mixture components. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), is primarily produced via industrial processes including incineration and the manufacture of herbicides. Both endosulfan and TCDD are persistent organic pollutants which elicit cytotoxic effects by inducing reactive oxygen species generation. Sublethal concentrations of mixtures of TCDD and endosulfan increase oxidative stress, as well as mitochondrial homeostasis disruption, which is preceded by a calcium rise and, in fine, induce cell death. TCDD+Endosulfan elicit a complex signaling sequence involving reticulum endoplasmic destalilization which leads to Ca 2+ rise, superoxide anion production, ATP drop and late NADP(H) depletion associated with a mitochondrial induced apoptosis concomitant early autophagic processes. The ROS scavenger, N-acetyl-cysteine, blocks both the mixture-induced autophagy and death. Calcium chelators act similarly and mitochondrially targeted anti-oxidants also abrogate these effects. Inhibition of the autophagic fluxes with 3-methyladenine, increases mixture-induced cell death. These findings show that subchronic doses of pollutants may act synergistically. They also reveal that the onset of autophagy might serve as a protective mechanism against ROS-triggered cytotoxic effects of a cocktail of pollutants in Caco-2 cells and increase their tumorigenicity.

G-quadruplex-interacting compounds alter latent DNA replication and episomal persistence of KSHV.

PubMed

Madireddy, Advaitha; Purushothaman, Pravinkumar; Loosbroock, Christopher P; Robertson, Erle S; Schildkraut, Carl L; Verma, Subhash C

2016-05-05

Kaposi's sarcoma associated herpesvirus (KSHV) establishes life-long latent infection by persisting as an extra-chromosomal episome in the infected cells and by maintaining its genome in dividing cells. KSHV achieves this by tethering its epigenome to the host chromosome by latency associated nuclear antigen (LANA), which binds in the terminal repeat (TR) region of the viral genome. Sequence analysis of the TR, a GC-rich DNA element, identified several potential Quadruplex G-Rich Sequences (QGRS). Since quadruplexes have the tendency to obstruct DNA replication, we used G-quadruplex stabilizing compounds to examine their effect on latent DNA replication and the persistence of viral episomes. Our results showed that these G-quadruplex stabilizing compounds led to the activation of dormant origins of DNA replication, with preferential bi-directional pausing of replications forks moving out of the TR region, implicating the role of the G-rich TR in the perturbation of episomal DNA replication. Over time, treatment with PhenDC3 showed a loss of viral episomes in the infected cells. Overall, these data show that G-quadruplex stabilizing compounds retard the progression of replication forks leading to a reduction in DNA replication and episomal maintenance. These results suggest a potential role for G-quadruplex stabilizers in the treatment of KSHV-associated diseases. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

A rational approach to selecting and ranking some pharmaceuticals of concern for the aquatic environment and their relative importance compared with other chemicals.

PubMed

Donnachie, Rachel L; Johnson, Andrew C; Sumpter, John P

2016-04-01

Aquatic organisms can be exposed to thousands of chemicals discharged by the human population. Many of these chemicals are considered disruptive to aquatic wildlife, and the literature on the impacts of these chemicals grows daily. However, because time and resources are not infinite, research must focus on the chemicals that represent the greatest threat. One group of chemicals of increasing concern is pharmaceuticals, for which the primary challenge is to identify which represent the greatest threat. In the present study, a list of 12 pharmaceuticals was compiled based on scoring the prevalence of different compounds from previous prioritization reviews. These included rankings based on prescription data, environmental concentrations, predicted environmental concentration/predicted no-effect concentration (PEC/PNEC) ratios, persistency/bioaccumulation/(eco)toxicity (PBT), and fish plasma model approaches. The most frequently cited were diclofenac, paracetamol, ibuprofen, carbamazepine, naproxen, atenolol, ethinyl estradiol, aspirin, fluoxetine, propranolol, metoprolol, and sulfamethoxazole. For each pharmaceutical, literature on effect concentrations was compiled and compared with river concentrations in the United Kingdom. The pharmaceuticals were ranked by degree of difference between the median effect and median river concentrations. Ethinyl estradiol was ranked as the highest concern, followed by fluoxetine, propranolol, and paracetamol. The relative risk of these pharmaceuticals was compared with those of metals and some persistent organic pollutants. Pharmaceuticals appear to be less of a threat to aquatic organisms than some metals (Cu, Al, Zn) and triclosan, using this ranking approach. © 2015 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

Environmental risk assessment of selected organic chemicals based on TOC test and QSAR estimation models.

PubMed

Chi, Yulang; Zhang, Huanteng; Huang, Qiansheng; Lin, Yi; Ye, Guozhu; Zhu, Huimin; Dong, Sijun

2018-02-01

Environmental risks of organic chemicals have been greatly determined by their persistence, bioaccumulation, and toxicity (PBT) and physicochemical properties. Major regulations in different countries and regions identify chemicals according to their bioconcentration factor (BCF) and octanol-water partition coefficient (Kow), which frequently displays a substantial correlation with the sediment sorption coefficient (Koc). Half-life or degradability is crucial for the persistence evaluation of chemicals. Quantitative structure activity relationship (QSAR) estimation models are indispensable for predicting environmental fate and health effects in the absence of field- or laboratory-based data. In this study, 39 chemicals of high concern were chosen for half-life testing based on total organic carbon (TOC) degradation, and two widely accepted and highly used QSAR estimation models (i.e., EPI Suite and PBT Profiler) were adopted for environmental risk evaluation. The experimental results and estimated data, as well as the two model-based results were compared, based on the water solubility, Kow, Koc, BCF and half-life. Environmental risk assessment of the selected compounds was achieved by combining experimental data and estimation models. It was concluded that both EPI Suite and PBT Profiler were fairly accurate in measuring the physicochemical properties and degradation half-lives for water, soil, and sediment. However, the half-lives between the experimental and the estimated results were still not absolutely consistent. This suggests deficiencies of the prediction models in some ways, and the necessity to combine the experimental data and predicted results for the evaluation of environmental fate and risks of pollutants. Copyright © 2016. Published by Elsevier B.V.

Long-Term Persistence of Pesticides and TPs in Archived Agricultural Soil Samples and Comparison with Pesticide Application.

PubMed

Chiaia-Hernandez, Aurea C; Keller, Armin; Wächter, Daniel; Steinlin, Christine; Camenzuli, Louise; Hollender, Juliane; Krauss, Martin

2017-09-19

For polar and more degradable pesticides, not many data on long-term persistence in soil under field conditions and real application practices exist. To assess the persistence of pesticides in soil, a multiple-compound screening method (log K ow 1.7-5.5) was developed based on pressurized liquid extraction, QuEChERS and LC-HRMS. The method was applied to study 80 polar pesticides and >90 transformation products (TPs) in archived topsoil samples from the Swiss Soil Monitoring Network (NABO) from 1995 to 2008 with known pesticide application patterns. The results reveal large variations between crop type and field sites. For the majority of the sites 10-15 pesticides were identified with a detection rate of 45% at concentrations between 1 and 330 μg/kg dw in soil. Furthermore, TPs were detected in 47% of the cases where the "parent-compound" was applied. Overall, residues of about 80% of all applied pesticides could be detected with half of these found as TPs with a persistence of more than a decade.

Ultrabright fluorescent OLEDS using triplet sinks

DOEpatents

Zhang, Yifan; Forrest, Stephen R; Thompson, Mark

2013-06-04

A first device is provided. The first device further comprises an organic light emitting device. The organic light emitting device further comprises an anode, a cathode, and an emissive layer disposed between the anode and the cathode. The emissive layer further comprises an organic host compound, an organic emitting compound capable of fluorescent emission at room temperature, and an organic dopant compound. The triplet energy of the dopant compound is lower than the triplet energy of the host compound. The dopant compound does not strongly absorb the fluorescent emission of the emitting compound.

Novel Polyfluorinated Compounds Identified Using High Resolution Mass Spectrometry Downstream of Manufacturing Facilities near Decatur, Alabama

EPA Science Inventory

Concern over persistence, bioaccumulation, and toxicity has led to international regulation and phase-outs of certain perfluorinated compounds and little is known about their replacement products. High resolution mass spectrometry was used to investigate the occurrence and identi...

[Impact of chemical and physical environmental factors on the course and outcome of pregnancy].

PubMed

Slama, R; Cordier, S

2013-09-01

We review the epidemiological literature on the possible impact of chemical and physical factors on pregnancy outcome. Effects of in-utero exposures on child health are not considered here. The highest levels of evidence concern the effects of passive smoking (on fetal growth), of lead (pregnancy-induced hypertension, fetal growth), of some Polychlorinated Biphenyls (PCB; on fetal growth) and, to a lesser extent, of atmospheric pollutants (on fetal growth and preterm delivery). For the other compounds, in particular non-persistent chemicals, the literature, which is generally based on poor exposure assessment, is less informative. In conclusion, the last decades have witnessed the development of mother-child cohorts in which exposure biomarkers have been assayed, allowing a large number of publications. For some persistent compounds, for which efficient exposure assessment approaches have been used, the literature indicates a likely impact on pregnancy outcomes. With the exception of air pollutants, the literature on non-persistent compounds is little conclusive; the assay of exposure biomarkers in repeated biological samples collected at relevant time points could help further increase knowledge regarding any health impact. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Levels and distributions of organic pollutants in subtidal sediments from the Loire estuary: Are there any relationships with TTR-binding activity?

NASA Astrophysics Data System (ADS)

Couderc, M.; Gandolfi, F.; Zalouk-Vergnoux, A.; Beyeler, N.; Malleret, L.; Ambidina, I.; Kamari, A.; Blanchet-Letrouvé, I.; Mouneyrac, C.; Hamers, T.; Poirier, L.

2016-12-01

The Loire estuary runs through important urban sites with shipping, industrial and agricultural activities, being the receptacle of diffusive pollutants comprising, a mixture of contaminants such as persistent organic pollutants (POPs). This work was set out to evaluate the occurrence of thyroid endocrine disruptors in sediments of this estuary. Sediments were collected in September 2012 and April 2013, in subtidal zones along the estuary. Targeted chemical analyses of five classes of pollutants, i.e. polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), alkylphenols (APs), and bisphenol A (BPA) were performed in sediment extracts. Extracts were further tested for their thyroid hormone (TH) disrupting potency to compete with TH for binding to its transporter protein transthyretin (TTR). The Haute-Indre site was characterized by a significant PAH contamination whereas Saint-Nazaire, Bellevue and Rezé would be particularly contaminated by PCBs. These observations could be linked to the different type of anthropogenic activities taking place close to these sites. Donges, Mindin and Paimboeuf were the sampling sites displaying the lowest contamination in PAHs, APs, PCBs and PBDEs. No inter-site difference could be observed for TTR-binding activity, which should be attributed to different compounds than the chemically analyzed compounds, as confirmed by PCA analyses. Furthermore, the TTR-binding potencies of the extracts were relatively low compared to data from literature. More investigations on the quantification of PCB and PBDE hydroxylated metabolites and other known endocrine disruptors such as pesticides or perfluorinated compounds could be considered, as well as bioassays highlighting other endocrine disrupting effects.

Bioaccumulation of organohalogenated compounds in sharks and rays from the southeastern USA.

PubMed

Weijs, Liesbeth; Briels, Nathalie; Adams, Douglas H; Lepoint, Gilles; Das, Krishna; Blust, Ronny; Covaci, Adrian

2015-02-01

Organohalogenated compounds are widespread in the marine environment and can be a serious threat to organisms in all levels of aquatic food webs, including elasmobranch species. Information about the concentrations of POPs (persistent organic pollutants) and of MeO-PBDEs (methoxylated polybrominated diphenyl ethers) in elasmobranchs is scarce and potential toxic effects are poorly understood. The aims of the present study were therefore to investigate the occurrence of multiple POP classes (PCBs, PBDEs, DDXs, HCB, CHLs) and of MeO-PBDEs in various elasmobranch species from different trophic levels in estuarine and marine waters of the southeastern United States. Overall, levels and patterns of PCBs, PBDEs, DDXs, HCB, CHLs and of MeO-PBDEs varied according to the species, maturity stage, gender and habitat type. The lowest levels of POPs were found in Atlantic stingrays and the highest levels were found in bull sharks. As both species are respectively near the bottom and at top of the trophic web, with juvenile bull sharks frequently feeding on Atlantic stingrays, these findings further suggest a bioaccumulation and biomagnification process with trophic position. MeO-PBDEs were not detected in Atlantic stingrays, but were found in all shark species. HCB was not found in Atlantic stingrays, bonnetheads or lemon sharks, but was detected in the majority of bull sharks examined. Comparison with previous studies suggests that Atlantic stingrays may be experiencing toxic effects of PCBs and DDXs on their immune system. However, the effect of these compounds on the health of shark species remains unclear. Copyright © 2014 Elsevier Inc. All rights reserved.

[Concentrations of persistent toxic compounds in the Spanish population: a puzzle without pieces and the protection of public health].

PubMed

Porta, M; Kogevinas, M; Zumeta, E; Sunyer, J; Ribas-Fitó, N; Ruiz, Laura; Jariod, Manuel; Vioque, Jesús; Alguacil, Juan; Martín, Piedad; Malats, Núria; Ayude, Daniel

2002-01-01

The contamination by persistent toxic compounds (PTCs) of the general population is a fact of relevance from a public health perspective. It is also relevant to health care professionals, as well as for environmental, food, industrial and economic policies. Though in Spain information on food contamination by PTCs shows large time and geographic gaps, the scarcity of data is even more severe on the concentrations that PTCs have in people: a representative study of a general healthy population living in a wide geographic area has never been conducted in the country. However, the available studies indicate that around 80-100% of the population has detectable concentrations of DDE, PCBs, hexachlorbenzene or lindane. Studies on the effects that PTCs have upon humans are extremely infrequent in Spain. Yet, the international literature suggests that some PTCs may induce significant biological and clinical effects at doses below those traditionally deemed "safe". The mechanism of action of PTCs are not restricted to endocrine disruption. Assessing the clinical and social relevance of the more subtle and long-term effects of PTCs presents interesting challenges and opportunities. Spain and other European countries lack population indicators on the impact that environmental processes have on human health. Several government levels have a role to fulfill in the monitoring of biological levels of PTCs among persons in order to assess the risks of adverse health effects. Along with over a hundred other countries. Spain will soon try to implement the Stockholm treaty on persistent organic pollutants (POPs). This constitutes a new opportunity to develop more efficient policies to control PTC residues in food, humans and the environment. As part of the treaty implementation it is necessary to launch a Report on factors that influence body concentrations of PTCs in the Spain general population.

Spatial and Temporal Trends of Persistent Organic Chemicals with Emphasis on Brominated Flame Retardants

EPA Science Inventory

Rapid growth in chemical and agrochemical industries during the past century have resulted in the release of large numbers of persistent organic chemicals (POCs) into the environment. Since POCs are prevalent in air, water, soil and tissue of organisms throughout the world and r...

Stability of Soil Organic Matter in Alpine Ecosystems: No Relationship with Vegetation

NASA Astrophysics Data System (ADS)

Matteodo, M.; Sebag, D.; Vittoz, P.; Verrecchia, E. P.

2016-12-01

There is an emerging understanding of mechanisms governing soil organic matter (SOM) stability, which is challenging the historical view of carbon persistence1. According to this alternative vision, SOM stability is not directly regulated by the molecular structure of plant inputs (i.e. the historical view), but the biotic and abiotic conditions of the surrounding environment which play a major role and mediate the influence of compound chemistry. The persistence of SOM is thus influenced by ecological conditions, controlling the access and activity of decomposers' enzymes and being ecosystem-dependent. In this study, we investigated differences of (1) carbon content, and (2) stability of organic matter in litter and organomineral layers from the most widespread plant communities at the subalpine-alpine level of the Swiss Alps. For this purpose, 230 samples from 47 soil profiles have been analysed across seven plant communities, along a subalpine-alpine elevation gradient. Both calcareous and siliceous grasslands were studied, as well as snowbed and ridge communities. Aboveground litter and A horizons were sampled and analysed using Rock-Eval Pyrolysis, a proxy-technique commonly used for the investigation of organic matter composition and stability2,3. Results show that the litter layers of the seven plant communities are significantly different in terms of total organic carbon (TOC) content, but slightly variable in terms of stability. The situation is radically different in the organomineral horizons where the amount of organic carbon is interestingly homogeneous, as well as the SOM stability. In mineral horizons, the amount and stability of SOM are mainly driven by the geological settings, and therefore vary in the different plant communities. These results show a clear disconnection between organic, organomineral, and mineral horizons in terms of factors governing soil organic matter stability. Consistent with the recent view of the carbon balance, plant input seems to influence the litter C dynamics (qualitatively and quantitatively) but not the SOM stability in A and mineral horizons. References 1Schmidt MWI, et al. (2011) Nature 478, 49-56. 2Disnar JR, et al. (2003) Org. Geochem. 34, 327-343. 3Sebag D, et al. (2006) Eur. J. of Soil Sci. 57, 344-355.

Persistence of organic carbon in heated aerosol residuals measured during Tropical Composition Cloud and Climate Coupling (TC4)

NASA Astrophysics Data System (ADS)

Thornberry, T.; Froyd, K. D.; Murphy, D. M.; Thomson, D. S.; Anderson, B. E.; Thornhill, K. L.; Winstead, E. L.

2010-05-01

The Particle Analysis by Laser Mass Spectrometry (PALMS) single particle mass spectrometer was used to analyze the composition of the nonvolatile fraction of atmospheric aerosol in a number of different environments. The mass spectra of individual particles sampled through an inlet section heated to 300°C were compared to unheated particles during flights of the NASA DC-8 aircraft during the Tropical Composition Cloud and Climate Coupling (TC4) mission. Comparisons are presented of measurements made in the marine boundary layer, the free troposphere, and the continental boundary layer over the Colombian jungle. The heated section completely removed sulfate from the aerosols except for sodium sulfate and related compounds in sea salt particles. Organic material in sea salt particles was observed to be less volatile than chlorine. Biomass burning particles were more likely to survive heating than other mixed sulfate-organic particles. For all particle types, there was a significant contribution to the residues from carbonaceous material other than elemental carbon. These results demonstrate the remaining compositional complexity of aerosol residuals that survive heating in a thermal denuder.

Chemoselective Hydrodehalogenation of Organic Halides Utilizing Two-Dimensional Anionic Electrons of Inorganic Electride [Ca2N]+·e^.

PubMed

Kim, Ye Ji; Kim, Sun Min; Yu, Chunghyeon; Yoo, YoungMin; Cho, Eun Jin; Yang, Jung Woon; Kim, Sung Wng

2017-01-31

Halogenated organic compounds are important anthropogenic chemicals widely used in chemical industry, biology, and pharmacology; however, the persistence and inertness of organic halides cause human health problems and considerable environmental pollution. Thus, the elimination or replacement of halogen atoms with organic halides has been considered a central task in synthetic chemistry. In dehalogenation reactions, the consecutive single-electron transfer from reducing agents generates the radical and corresponding carbanion and thus removes the halogen atom as the leaving group. Herein, we report a new strategy for an efficient chemoselective hydrodehalogenation through the formation of stable carbanion intermediates, which are simply achieved by using highly mobile two-dimensional electrons of inorganic electride [Ca 2 N] + ·e - with effective electron transfer ability. The consecutive single-electron transfer from inorganic electride [Ca 2 N] + ·e - stabilized free carbanions, which is a key step in achieving the selective reaction. Furthermore, a determinant more important than leaving group ability is the stability control of free carbanions according to the s character determined by the backbone structure. We anticipate that this approach may provide new insight into selective chemical formation, including hydrodehalogenation.

Incorporation of in silico biodegradability screening in early drug development--a feasible approach?

PubMed

Steger-Hartmann, Thomas; Länge, Reinhard; Heuck, Klaus

2011-05-01

The concentration of a pharmaceutical found in the environment is determined by the amount used by the patient, the excretion and metabolism pattern, and eventually by its persistence. Biological degradation or persistence of a pharmaceutical is experimentally tested rather late in the development of a pharmaceutical, often shortly before submission of the dossier to regulatory authorities. To investigate whether the aspect of persistence of a compound could be assessed early during drug development, we investigated whether biodegradation of pharmaceuticals could be predicted with the help of in silico tools. To assess the value of in silico prediction, we collected results for the OECD 301 degradation test ("ready biodegradability") of 42 drugs or drug synthesis intermediates and compared them to the prediction of the in silico tool BIOWIN. Of these compounds, 38 were predictable with BIOWIN, which is a module of the Estimation Programs Interface (EPI) Suite™ provided by the US EPA. The program failed to predict the two drugs which proved to be readily biodegradable in the degradation tests. On the other hand, BIOWIN predicted two compounds to be readily biodegradable which, however, proved to be persistent in the test setting. The comparison of experimental data with the predicted one resulted in a specificity of 94% and a sensitivity of 0%. The results of this study do not indicate that application of the biodegradation prediction tool BIOWIN is a feasible approach to assess the ready biodegradability during early drug development.

RETINOID METABOLISM IN FISH EMBRYOS FROM SENSITIVE AND RESISTANT POPULATIONS EXPOSED TO DIOXIN-LIKE COMPOUNDS

EPA Science Inventory

Early developmental stages of fish are extremely sensitive to a class of toxic and persistent environmental contaminants known as dioxin-like compounds (DLCs). Most of the toxicological actions of DLCs are mediated via the Aryl hydrocarbon Receptor (AhR) that regulates transcript...

Serum concentrations of perfluorinated compounds (PFC) among selected populations of children and Adults in California

EPA Science Inventory

Perfluorinated compounds (PFCs) have been widely used in industrial applications and consumer products. Their persistent nature and potential health impacts are of concern. Given the high cost of collecting serum samples, this study is to understand whether we can quantify PFC se...

Differences in Pop Levels between Conventional and Omega-3 Fatty Acid-Enriched Milk and Dairy Products

PubMed Central

Guerranti, Cristiana; Focardi, Silvano Ettore

2011-01-01

Conventional and omega-3 fatty acid-enriched milk and cheese were analyzed for persistent organic pollutants (POPs). Omega-3-enriched products are usually supplemented with fish oil which is potentially contaminated. All classes of the considered POPs (PCBs, DDT, HCB, PBDEs, and PCDD/Fs) were found in the samples, with average concentrations higher in omega-3-enriched products than in conventional ones. For PCBs, DDT, and HCB, differences were statistically significant and, therefore, cannot be ascribed to normal variability. With regard to all classes of compounds, the highest levels in individual samples were always found in omega-3 products, in line with the hypothesis that these foods are potentially more contaminated than conventional ones. PMID:23724286

User’s guide to the collection and analysis of tree cores to assess the distribution of subsurface volatile organic compounds

USGS Publications Warehouse

Vroblesky, Don A.

2008-01-01

Analysis of the volatile organic compound content of tree cores is an inexpensive, rapid, simple approach to examining the distribution of subsurface volatile organic compound contaminants. The method has been shown to detect several volatile petroleum hydrocarbons and chlorinated aliphatic compounds associated with vapor intrusion and ground-water contamination. Tree cores, which are approximately 3 inches long, are obtained by using an increment borer. The cores are placed in vials and sealed. After a period of equilibration, the cores can be analyzed by headspace analysis gas chromatography. Because the roots are exposed to volatile organic compound contamination in the unsaturated zone or shallow ground water, the volatile organic compound concentrations in the tree cores are an indication of the presence of subsurface volatile organic compound contamination. Thus, tree coring can be used to detect and map subsurface volatile organic compound contamination. For comparison of tree-core data at a particular site, it is important to maintain consistent methods for all aspects of tree-core collection, handling, and analysis. Factors affecting the volatile organic compound concentrations in tree cores include the type of volatile organic compound, the tree species, the rooting depth, ground-water chemistry, the depth to the contaminated horizon, concentration differences around the trunk related to variations in the distribution of subsurface volatile organic compounds, concentration differences with depth of coring related to volatilization loss through the bark and possibly other unknown factors, dilution by rain, seasonal influences, sorption, vapor-exchange rates, and within-tree volatile organic compound degradation.

40 CFR 442.2 - General definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., organic chemicals including: alcohols, aldehydes, formaldehydes, phenols, peroxides, organic salts, amines, amides, other nitrogen compounds, other aromatic compounds, aliphatic organic chemicals, glycols, glycerines, and organic polymers; refractory organic compounds including: ketones, nitriles, organo-metallic...

Production of reactive oxygen species from abraded silicates. Implications for the reactivity of the Martian soil

NASA Astrophysics Data System (ADS)

Bak, Ebbe N.; Zafirov, Kaloyan; Merrison, Jonathan P.; Jensen, Svend J. Knak; Nørnberg, Per; Gunnlaugsson, Haraldur P.; Finster, Kai

2017-09-01

The results of the Labeled Release and the Gas Exchange experiments conducted on Mars by the Viking Landers show that compounds in the Martian soil can cause oxidation of organics and a release of oxygen in the presence of water. Several sources have been proposed for the oxidizing compounds, but none has been validated in situ and the cause of the observed oxidation has not been resolved. In this study, laboratory simulations of saltation were conducted to examine if and under which conditions wind abrasion of silicates, a process that is common on the Martian surface, can give rise to oxidants in the form of hydrogen peroxide (H2O2) and hydroxyl radicals (ṡOH). We found that silicate samples abraded in simulated Martian atmospheres gave rise to a significant production of H2O2 and ṡOH upon contact with water. Our experiments demonstrated that abraded silicates could lead to a production of H2O2 facilitated by atmospheric O2 and inhibited by carbon dioxide. Furthermore, during simulated saltation the silicate particles became triboelectrically charged and at pressures similar to the Martian surface pressure we observed glow discharges. Electrical discharges can cause dissociation of CO2 and through subsequent reactions lead to a production of H2O2. These results indicate that the reactions linked to electrical discharges are the dominant source of H2O2 during saltation of silicates in a simulated Martian atmosphere, given the low pressure and the relatively high concentration of CO2. Our experiments provide evidence that wind driven abrasion could enhance the reactivity of the Martian soil and thereby could have contributed to the oxidation of organic compounds and the O2 release observed in the Labeled Release and the Gas Exchange experiments. Furthermore, the release of H2O2 and ṡOH from abraded silicates could have a negative effect on the persistence of organic compounds in the Martian soil and the habitability of the Martian surface.

The Biogeochemistry of Sulfur in Hydrothermal Systems

NASA Technical Reports Server (NTRS)

Schulte, Mitchell; Rogers, K. L.; DeVincenzi, Donald L. (Technical Monitor)

2001-01-01

The incorporation of sulfur into many biomolecules likely dates back to the development of the earliest metabolic strategies. Sulfur is common in enzymes and co-enzymes and is an indispensable structural component in many peptides and proteins. Early metabolism may have been heavily influenced by the abundance of sulfide minerals in hydrothermal systems. The incorporation of sulfur into many biomolecules likely dates back to the development of the earliest metabolic strategies. Sulfur is common in enzymes and co-enzymes and is an indispensable structural component in many peptides and proteins. Early metabolism may have been heavily influenced by the abundance of sulfide minerals in hydrothermal systems. Understanding how sulfur became prevalent in biochemical processes and many biomolecules requires knowledge of the reaction properties of sulfur-bearing compounds. We have previously estimated thermodynamic data for thiols, the simplest organic sulfur compounds, at elevated temperatures and pressures. If life began in hydrothermal environments, it is especially important to understand reactions at elevated temperatures among sulfur-bearing compounds and other organic molecules essential for the origin and persistence of life. Here we examine reactions that may have formed amino acids with thiols as reaction intermediates in hypothetical early Earth hydrothermal environments. (There are two amino acids, cysteine and methionine, that contain sulfur.) Our calculations suggest that significant amounts of some amino acids were produced in early Earth hydrothermal fluids, given reasonable concentrations H2, NH3, H2S and CO. For example, preliminary results indicate that glycine activities as high as 1 mmol can be reached in these systems at 100 C. Alanine formation from propanethiol is also a favorable reaction. On the other hand, the calculated equilibrium log activities of cysteine and serine from propanethiol are -21 and -19, respectively, at 100 C. These results indicate that while amino acid formation with thiols as intermediates is favored in some cases, other mechanisms may have been necessary to produce significant amounts of other amino acids. Coupled with our previous results for thiols, these studies imply that sulfur may have been easily incorporated into the organic geochemistry of early Earth hydrothermal systems, leading to its widespread use in biomolecules. Formation of more complex biomolecules in hydrothermal systems may have required sulfur-bearing organic compounds as reaction intermediates.

Method for halogenating or radiohalogenating a chemical compound

DOEpatents

Kabalka, George W.

2006-05-09

A method for obtaining a halogenated organic compound, whereby an organotrifluoroborate compound is reacted with a halide ion in the presence of an oxidizing agent to produce the corresponding halogenated organic compound. The method may be used for producing radiohalogenated organic compounds.

Factors of Persistence for African American Men in a Student Support Organization

ERIC Educational Resources Information Center

Simmons, Lamont D.

2013-01-01

The purpose of this qualitative study is to examine factors of persistence for two African American men involved in the Project Empowerment (PE, pseudonym) student organization at a predominantly White institution. The participants are undergraduate student members of PE, a campus-based organization designed to enhance African American male…

AGGREGATE EXPOSURES OF NINE PRESCHOOL CHILDREN TO PERSISTENT ORGANIC POLLUTANTS AT DAY CARE AND AT HOME

EPA Science Inventory

In the summer of 1997, we measured the aggregate exposures of nine preschool children, ages two to five years, to a suite of organic pesticides and other persistent organic pollutants that are commonly found in the home and school environment. The children attended either of t...

Understanding of Cyclic Volatile Methyl Siloxane Fate in a High Latitude Lake Is Constrained by Uncertainty in Organic Carbon-Water Partitioning.

PubMed

Krogseth, Ingjerd Sunde; Whelan, Michael John; Christensen, Guttorm Normann; Breivik, Knut; Evenset, Anita; Warner, Nicholas Alexander

2017-01-03

Cyclic volatile methyl siloxanes (cVMS) are emitted to aquatic environments with wastewater effluents. Here, we evaluate the environmental behavior of three cVMS compounds (octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6)) in a high latitude lake (Storvannet, 70°N 23°E), experiencing intermittent wastewater emissions and high latitude environmental conditions (low temperatures and seasonal ice cover). Measured cVMS concentrations in lake water were below detection limits in both March and June 2014. However, mean concentrations in sediments were 207 ± 30, 3775 ± 973 and 848 ± 211 ng g -1 organic carbon for D4, D5 and D6, respectively. To rationalize measurements, a fugacity-based model for lakes (QWASI) was parametrized for Storvannet. The key removal process for cVMS from the lake was predicted to be advection due to the low hydraulic retention time of the lake, followed by volatilization. Predicted cVMS behavior was highly sensitive to the partition coefficient between organic carbon and water (K OC ) and its temperature dependence. Predictions indicated lower overall persistence with decreasing temperature due to enhanced partitioning from sediments to water. Inverse modeling to predict steady-state emissions from cVMS concentrations in sediment provided unrealistically high emissions, when evaluated against measured concentrations in sewage. However, high concentrations of cVMS in sediment and low concentrations in water could be explained via a hypothetical dynamic emission scenario consistent with combined sewer overflows. The study illustrates the importance of considering compound-specific behavior of emerging contaminants that may differ from legacy organic contaminants.

Immunomodulation by Persistent Organic Pollutants

EPA Science Inventory

Persistent organic pollutants (POPs) are widely distnbuted in the environment, are resistant to degradation, and increase in concentration (biomagnify) in the food chain. Concentrations in apical predators may be tens to hundreds of times greater than concentrations in their pref...

Article "403. Toxicology of Persistent Organic Pollutants (POPs)"

EPA Science Inventory

Persistent Organic Pollutants (POPs) are all synthetic chemicals, either intentionally or unintentionally produced/released. Some POPs are pesticides. Others are industrial products or unintended by-products resulting from industrial processes or combustions (see figure 1). POPs ...

Is there any consistency between the microplastics found in the field and those used in laboratory experiments?

PubMed

Phuong, Nam Ngoc; Zalouk-Vergnoux, Aurore; Poirier, Laurence; Kamari, Abderrahmane; Châtel, Amélie; Mouneyrac, Catherine; Lagarde, Fabienne

2016-04-01

The ubiquitous presence and persistency of microplastics (MPs) in aquatic environments are of particular concern since they represent an increasing threat to marine organisms and ecosystems. Great differences of concentrations and/or quantities in field samples have been observed depending on geographical location around the world. The main types reported have been polyethylene, polypropylene, and polystyrene. The presence of MPs in marine wildlife has been shown in many studies focusing on ingestion and accumulation in different tissues, whereas studies of the biological effects of MPs in the field are scarce. If the nature and abundance/concentrations of MPs have not been systematically determined in field samples, this is due to the fact that the identification of MPs from environmental samples requires mastery and execution of several steps and techniques. For this reason and due to differences in sampling techniques and sample preparation, it remains difficult to compare the published studies. Most laboratory experiments have been performed with MP concentrations of a higher order of magnitude than those found in the field. Consequently, the ingestion and associated effects observed in exposed organisms have corresponded to great contaminant stress, which does not mimic the natural environment. Medium contaminations are produced with only one type of polymer of a precise sizes and homogenous shape whereas the MPs present in the field are known to be a mix of many types, sizes and shapes of plastic. Moreover, MPs originating in marine environments can be colonized by organisms and constitute the sorption support for many organic compounds present in environment that are not easily reproducible in laboratory. Determination of the mechanical and chemical effects of MPs on organisms is still a challenging area of research. Among the potential chemical effects it is necessary to differentiate those related to polymer properties from those due to the sorption/desorption of organic compounds. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biodegradation of NSO-compounds under different redox-conditions

NASA Astrophysics Data System (ADS)

Dyreborg, S.; Arvin, E.; Broholm, K.

1997-03-01

Laboratory experiments were carried out to investigate the potential of groundwater microorganisms to degrade selected heterocyclic aromatic compounds containing nitrogen, sulphur, or oxygen (NSO-compounds) under four redox-conditions over a period of 846 days. Eight compounds (pyrrole, 1-methylpyrrole, quinoline, indole, carbazole, dibenzothiophene, benzofuran, and dibenzofuran) were degraded under aerobic conditions, whereas thiophene and benzothiophene were degraded only when other compounds were degraded concomitantly. Quinoline and indole were the only two NSO-compounds degraded under anaerobic conditions, even though the microorganisms present in the anaerobic microcosms were active throughout the incubation period. A high variability in the lag period among the NSO-compounds was observed under aerobic conditions. While quinoline, indole, and carbazole were degraded with a lag period of 3-25 days, the lag periods for pyrrole, dibenzothiophene, benzofuran, and dibenzofuran were significantly longer (29-278 days). Under anaerobic conditions, lag periods of 100-300 days were observed. Differences in the degradation rate among the compounds were also observed. Indole, quinoline, carbazole, and benzofuran were quickly degraded in the aerobic microcosms, whereas a slow degradation of dibenzothiophene and dibenzofuran was observed. Pyrrole and 1-methylpyrrole were slowly degraded and 1-methylpyrrole was not completely removed within the 846 days. The anaerobic degradation rate was significantly slower than the aerobic degradation rate. The degradation rate under sulphate-reducing conditions was higher than under denitrifying and methanogenic conditions, though after re-addition of a compound a quick removal was observed. The persistence of many NSO-compounds under anaerobic conditions together with the long lag periods and the low degradation rates under aerobic conditions suggest that NSO-compounds might persist in groundwater at creosote-contaminated sites.

Assessment of soil organic matter persistence under different land uses applying a physical fractionation procedure

NASA Astrophysics Data System (ADS)

Giannetta, Beatrice; Plaza, César; López-de-Sá, Esther G.; Vischetti, Costantino; Zaccone, Claudio

2017-04-01

The understanding of the mechanisms involved in the build-up of soil organic matter (SOM) pools with long residence time is tightly linked to the comprehension of C dynamics. Organo-mineral associations are known to be strongly correlated with the accumulation of selective preserved C forms. Adsorption to minerals, as well as occlusion within aggregates, may affect SOM protection in different ways depending on its molecular structure and pedo-climatic conditions. In this research, we investigated changes in quantity and quality of SOM pools characterized by different protection mechanisms in coniferous and broadleaved forest soils, grassland soils, technosols and an agricultural soil with different organic amendments, in order to evaluate the influence of both land use and organic matter nature on physical and/or chemical stabilization of SOM. In particular, free (FR), intra-macroaggregate (MA), intra-microaggregate (MI), and mineral-associated (Min) fractions were separated in order to define physical and chemical mechanisms responsible for the SOM protection against degradation. All these SOM fractions were analyzed for organic C and total N concentration, and their stability assessed by thermogravimetric analysis (TD-TGA). Preliminary data show that, for all land uses, most of the organic C (40-60%) is found in the Min pool, followed by FR (20-40%)>MI MA. With the only exception of the FR, no significant correlations were found between the C/N ratio and a thermal stability index (H550-400/400-250) of each fraction; at the same time, a highly significant and positive correlation was found between these two parameters in all fractions isolated from agricultural soils. In particular, the thermal stability index measured in all Min fractions may be related to the more marked presence of labile compounds in this pool relative to recalcitrant compounds. Conversely, FR OM could not always represent a fresh and readily decomposable fraction.Furthermore, OM associated with soil minerals exhibits a low C/N ratio, possibly attributed to the association of proteins and peptides with the mineral phase. Future research steps will allow a better understanding of the role of molecular structure on SOM stabilization mechanisms, with a particular focus on the description of C and N compounds in organo-mineral associations.

Water contamination by endocrine disruptors: Impacts, microbiological aspects and trends for environmental protection.

PubMed

Vilela, Caren Leite Spindola; Bassin, João Paulo; Peixoto, Raquel Silva

2018-04-01

Hormone active agents constitute a dangerous class of pollutants. Among them, those agents that mimic the action of estrogens on target cells and are part of the group of endocrine-disruptor compounds (EDCs) are termed estrogenic EDCs, the main focus of this review. Exposure to these compounds causes a number of negative effects, including breast cancer, infertility and animal hermaphroditism. However, especially in underdeveloped countries, limited efforts have been made to warn people about this serious issue, explain the methods of minimizing exposure, and develop feasible and efficient mitigation strategies at different levels and in various environments. For instance, the use of bioremediation processes capable of transforming EDCs into environmentally friendly compounds has been little explored. A wide diversity of estrogen-degrading microorganisms could be used to develop such technologies, which include bioremediation processes for EDCs that could be implemented in biological filters for the post-treatment of wastewater effluent. This review describes problems associated with EDCs, primarily estrogenic EDCs, including exposure as well as the present status of understanding and the effects of natural and synthetic hormones and estrogenic EDCs on living organisms. We also describe potential biotechnological strategies for EDC biodegradation, and suggest novel treatment approaches for minimizing the persistence of EDCs in the environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Isotopic exchangeability as a measure of the available fraction of the human pharmaceutical carbamazepine in river sediment.

PubMed

Williams, Mike; Kookana, Rai

2010-08-01

Cabamazepine (CBZ), an antiepileptic pharmaceutical compound, is a pollutant of aquatic ecosystems entering via wastewater treatment plants that is considered to be persistent to degradation. An isotope exchange technique was employed using radiolabelled CBZ as a model compound, to determine the amount of isotopic exchangeability of CBZ in river sediment. The amount of isotopically exchangeable CBZ was used as an estimate of the extent of desorption hysteresis in solution from river sediment, including a treatment where the sediment was amended with black carbon. The isotopically exchangeable CBZ was measured by equilibrating 12C-CBZ with sediment for 0 to 28 days followed by a 24 hour equilibration with 14C-CBZ at the end of the incubation period. The isotopically exchangeable fraction of CBZ decreased over time in the sediment, particularly following amendment with black carbon. This has important implications for the fate of CBZ, which, apart from being resistant to degradation, is constantly released into aquatic ecosystems from wastewater treatment plants. This study demonstrates the availability of a relatively quick and simple alternative to batch desorption techniques for the assessment of the available fraction of organic compounds in sediments following their release into aquatic ecosystems. 2010. Published by Elsevier B.V. All rights reserved.

ENVIRONMENTAL ANALYTICAL CHEMISTRY OF ...

EPA Pesticide Factsheets

Within the scope of a number of emerging contaminant issues in environmental analysis, one area that has received a great deal of public interest has been the assessment of the role of pharmaceuticals and personal care products (PPCPs) as stressors and agents of change in ecosystems as well as their role in unplanned human exposure. The relationship between personal actions and the occurrence of PPCPs in the environment is clear-cut and comprehensible to the public. In this overview, we attempt to examine the separations aspect of the analytical approach to the vast array of potential analytes among this class of compounds. We also highlight the relationship between these compounds and endocrine disrupting compounds (EDCs) and between PPCPs and EDCs and the more traditional environmental analytes such as the persistent organic pollutants (POPs). Although the spectrum of chemical behavior extends from hydrophobic to hydrophilic, the current focus has shifted to moderately and highly polar analytes. Thus, emphasis on HPLC and LC/MS has grown and MS/MS has become a detection technique of choice with either electrospray ionization or atmospheric pressure chemical ionization. This contrasts markedly with the bench mark approach of capillary GC, GC/MS and electron ionization in traditional environmental analysis. The expansion of the analyte list has fostered new vigor in the development of environmental analytical chemistry, modernized the range of tools appli

Determination of a broad spectrum of pharmaceuticals and endocrine disruptors in biofilm from a waste water treatment plant-impacted river.

PubMed

Huerta, B; Rodriguez-Mozaz, S; Nannou, C; Nakis, L; Ruhí, A; Acuña, V; Sabater, S; Barcelo, D

2016-01-01

Wastewater treatment plants (WWTPs) are one of the main sources of pharmaceuticals and endocrine disrupting compounds in freshwater ecosystems, and several studies have reported bioaccumulation of these compounds in different organisms in those ecosystems. River biofilms are exceptional indicators of pollution, but very few studies have focused on the accumulation of these emerging contaminants. The objectives of this study were first to develop an efficient analytical methodology for the simultaneous analysis of 44 pharmaceuticals and 13 endocrine disrupting compounds in biofilm, and second, to assess persistence, distribution, and bioaccumulation of these contaminants in natural biofilms inhabiting a WWTP-impacted river. The method is based on pressurized liquid extraction, purification by solid-phase extraction, and analysis by ultra performance liquid chromatography coupled to a mass spectrometer (UPLC-MS/MS) in tandem. Recoveries for pharmaceuticals were 31-137%, and for endocrine disruptors 32-93%. Method detection limits for endocrine disruptors were in the range of 0.2-2.4 ng g(-1), and for pharmaceuticals, 0.07-6.7 ng g(-1). A total of five endocrine disruptors and seven pharmaceuticals were detected in field samples at concentrations up to 100 ng g(-1). Copyright © 2015. Published by Elsevier B.V.

Pesticide nonextractable residue formation in soil: insights from inverse modeling of degradation time series.

PubMed

Loos, Martin; Krauss, Martin; Fenner, Kathrin

2012-09-18

Formation of soil nonextractable residues (NER) is central to the fate and persistence of pesticides. To investigate pools and extent of NER formation, an established inverse modeling approach for pesticide soil degradation time series was evaluated with a Monte Carlo Markov Chain (MCMC) sampling procedure. It was found that only half of 73 pesticide degradation time series from a homogeneous soil source allowed for well-behaved identification of kinetic parameters with a four-pool model containing a parent compound, a metabolite, a volatile, and a NER pool. A subsequent simulation indeed confirmed distinct parameter combinations of low identifiability. Taking the resulting uncertainties into account, several conclusions regarding NER formation and its impact on persistence assessment could nonetheless be drawn. First, rate constants for transformation of parent compounds to metabolites were correlated to those for transformation of parent compounds to NER, leading to degradation half-lives (DegT50) typically not being larger than disappearance half-lives (DT50) by more than a factor of 2. Second, estimated rate constants were used to evaluate NER formation over time. This showed that NER formation, particularly through the metabolite pool, may be grossly underestimated when using standard incubation periods. It further showed that amounts and uncertainties in (i) total NER, (ii) NER formed from the parent pool, and (iii) NER formed from the metabolite pool vary considerably among data sets at t→∞, with no clear dominance between (ii) and (iii). However, compounds containing aromatic amine moieties were found to form significantly more total NER when extrapolating to t→∞ than the other compounds studied. Overall, our study stresses the general need for assessing uncertainties, identifiability issues, and resulting biases when using inverse modeling of degradation time series for evaluating persistence and NER formation.

Occurrence, fate and transformation of emerging contaminants in water: An overarching review of the field.

PubMed

Wilkinson, John; Hooda, Peter S; Barker, James; Barton, Stephen; Swinden, Julian

2017-12-01

Many of the products and drugs used commonly contain chemical components which may persist through sewage treatment works (STW) and eventually enter the aquatic environment as parent compounds, metabolites, or transformation products. Pharmaceuticals and personal care products (PPCPs) and other emerging contaminants (ECs) have been detected in waters (typically ng/L) as well as more recently bound to sediment and plastic particles (typically ng/g). Despite significant advancement of knowledge since the late 1990s, the fate of these contaminants/transformation products once introduced into the aquatic environment remains relatively unresolved. This review provides a unique focus on the fate of seven major groups of PPCPs/ECs in the aquatic environment, which is frequently not found in similar works which are often compound or topic-specific and limited in background knowledge. Key findings include: a) some replacements for regulation precluded/banned chemicals may be similarly persistent in the environment as those they replace, b) the adsorption of potentially bioactive chemicals to micro- and nanoplastics is a significant topic with risks to aquatic organisms potentially greater than previously thought, and c) micro-/nanoplastics are likely to remain of significant concern for centuries after regulatory limitations on their use become active due to the slow degradation of macro-plastics into smaller components. An interdisciplinary perspective on recent advances in the field is presented here in a unique way which highlights both the principle science and direction of research needed to elucidate the fate and transport patterns of aquatic PPCPs/ECs. Unlike similar reviews, which are often topic-specific, here we aim to present an overarching review of the field with focus on the occurrence, transformation and fate of emerging contaminants. Environmental presence of seven major classes of contaminants (analygesics, antibiotics, antineoplastics, beta-blockers, perfluorinated compounds, personal care products and plasticisers), factors affecting contaminant fate, association with plastic micro-/nanoparticles and photochemical transformation are comprehensively evaluated. Copyright © 2017 Elsevier Ltd. All rights reserved.

Availability of ferric iron for microbial reduction in bottom sediments of the freshwater tidal potomac river.

PubMed

Lovley, D R; Phillips, E J

1986-10-01

The distribution of Fe(III), its availability for microbial reduction, and factors controlling Fe(III) availability were investigated in sediments from a freshwater site in the Potomac River Estuary. Fe(III) reduction in sediments incubated under anaerobic conditions and depth profiles of oxalate-extractable Fe(III) indicated that Fe(III) reduction was limited to depths of 4 cm or less, with the most intense Fe(III) reduction in the top 1 cm. In incubations of the upper 4 cm of the sediments, Fe(III) reduction was as important as methane production as a pathway for anaerobic electron flow because of the high rates of Fe(III) reduction in the 0- to 0.5-cm interval. Most of the oxalate-extractable Fe(III) in the sediments was not reduced and persisted to a depth of at least 20 cm. The incomplete reduction was not the result of a lack of suitable electron donors. The oxalate-extractable Fe(III) that was preserved in the sediments was considered to be in a form other than amorphous Fe(III) oxyhydroxide, since synthetic amorphous Fe(III) oxyhydroxide, amorphous Fe(III) oxyhydroxide adsorbed onto clay, and amorphous Fe(III) oxyhydroxide saturated with adsorbed phosphate or fulvic acids were all readily reduced. Fe(3)O(4) and the mixed Fe(III)-Fe(II) compound(s) that were produced during the reduction of amorphous Fe(III) oxyhydroxide in an enrichment culture were oxalate extractable but were not reduced, suggesting that mixed Fe(III)-Fe(II) compounds might account for the persistence of oxalate-extractable Fe(III) in the sediments. The availability of microbially reducible Fe(III) in surficial sediments demonstrates that microbial Fe(III) reduction can be important to organic matter decomposition and iron geochemistry. However, the overall extent of microbial Fe(III) reduction is governed by the inability of microorganisms to reduce most of the Fe(III) in the sediment.

Simplification and validation of a large volume polyurethane foam sampler for the analysis of persistent hydrophobic compounds in drinking water.

PubMed

Choi, J W; Lee, J H; Moon, B S; Kannan, K

2008-08-01

The use of a large volume polyurethane foam (PUF) sampler was validated for rapid extraction of persistent organic pollutants (POPs), such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), in raw water and treated water from drinking water plants. To validate the recovery of target compounds in the sampling process, a (37)Cl-labeled standard was spiked into the 1st PUF plug prior to filtration. An accelerated solvent extraction method, as a pressurized liquid extractor (PLE), was optimized to extract the PUF plug. For sample preparation, tandem column chromatography (TCC) clean-up was used for rapid analysis. The recoveries of labeled compounds in the analytical method were 80-110% (n = 9). The optimized PUF-PLE-TCC method was applied in the analysis of raw water and treated potable water from seven drinking water plants in South Korea. The sample volume used was between 18 and 102 L for raw water at a flow rate of 0.4-2 L min(-1), 95 and 107 L for treated water at a flow rate of 1.5-2.2 L min(-1). Limit of quantitation (LOQ) was a function of sample volume and it decreased with increasing sample volume. The LOQ of PCDD/Fs in raw waters analyzed by this method was 3-11 times lower than that described using large-size disk-type solid phase extraction (SPE) method. The LOQ of PCDD/F congeners in raw water and treated water were 0.022-3.9 ng L(-1) and 0.018-0.74 ng L(-1), respectively. Octachlorinated dibenzo-p-dioxin (OCDD) was found in some raw water samples, while their concentrations were well below the tentative criterion set by the Japanese Environmental Ministry for drinking water. OCDD was below the LOQ in the treated drinking water.

Enantioselectivity of the bioconversion of chiral citronellal during the inhibition of wheat seeds germination.

PubMed

Cavalieri, Andrea; Fischer, Ravit; Larkov, Olga; Dudai, Nativ

2014-03-01

Citronellal is one of the most prominent monoterpenes present in many essential oils. Low persistence of essential oils as bioherbicides has often been addressed because of the high volatility of these compounds. Bioconversion of citronellal by wheat seeds releases less aggressive and injurious compounds as demonstrated by their diminished germination. We demonstrated that optically pure citronellal enantiomers were reduced to optically pure citronellol enantiomers with retention of the configuration both in isolated wheat embryos and endosperms. Our findings reveal the potential of essential oils as allelopathic agents providing an insight into their mechanism of action and persistence. Copyright © 2014 Verlag Helvetica Chimica Acta AG, Zürich.

How efficient are constructed wetlands in removing pharmaceuticals from untreated and treated urban wastewaters? A review.

PubMed

Verlicchi, Paola; Zambello, Elena

2014-02-01

This review presents and discusses the data from 47 peer-reviewed journal articles on the occurrence of 137 pharmaceutical compounds in the effluent from various types of constructed wetlands treating urban wastewater. We analyse the observed removal efficiencies of the investigated compounds in order to identify the type of constructed wetland that best removes those most frequently detected. The literature reviewed details experimental investigations carried out on 136 treatment plants, including free water surface systems, as well as horizontal and vertical subsurface flow beds (pilot or full-scale) acting as primary, secondary or tertiary treatments. The occurrence of selected pharmaceuticals in sediments and gravel and their uptake by common macrophytes are also presented and discussed. We analyse the main removal mechanisms for the selected compounds and investigate the influence of the main design parameters, as well as operational and environmental conditions of the treatment systems on removal efficiency. We also report on previous attempts to correlate observed removal values with the chemical structure and chemical-physical properties (mainly pKa and LogKow) of pharmaceutical compounds. We then use the literature data to calculate the average pharmaceutical mass loadings in the effluent from constructed wetlands, comparing the ability of such systems to remove selected pharmaceuticals with the corresponding conventional secondary and tertiary treatments. Finally, the environmental risk posed by pharmaceutical residues in effluents from constructed wetlands acting as secondary and tertiary treatment steps is calculated in the form of the risk quotient ratio. This approach enabled us to provide a ranking of the most critical compounds for the two scenarios, to discuss the ramifications of the adoption of constructed wetlands for removing such persistent organic compounds, and to propose avenues of future research. © 2013.

An overview on the potential of natural products as ureases inhibitors: A review☆

PubMed Central

Modolo, Luzia V.; de Souza, Aline X.; Horta, Lívia P.; Araujo, Débora P.; de Fátima, Ângelo

2014-01-01

Ureases, enzymes that catalyze urea hydrolysis, have received considerable attention for their impact on living organisms’ health and life quality. On the one hand, the persistence of urease activity in human and animal cells can be the cause of some diseases and pathogen infections. On the other hand, food production can be negatively affected by ureases of soil microbiota that, in turn, lead to losses of nitrogenous nutrients in fields supplemented with urea as fertilizer. In this context, nature has proven to be a rich resource of natural products bearing a variety of scaffolds that decrease the ureolytic activity of ureases from different organisms. Therefore, this work compiles the state-of-the-art researches focused on the potential of plant natural products (present in extracts or as pure compounds) as urease inhibitors of clinical and/or agricultural interests. Emphasis is given to ureases of Helicobacter pylori, Canavalia ensiformis and soil microbiota although the active site of this class of hydrolases is conserved among living organisms. PMID:25685542

Dietary Anthocyanins and Insulin Resistance: When Food Becomes a Medicine.

PubMed

Belwal, Tarun; Nabavi, Seyed Fazel; Nabavi, Seyed Mohammad; Habtemariam, Solomon

2017-10-12

Insulin resistance is an abnormal physiological state that occurs when insulin from pancreatic β-cells is unable to trigger a signal transduction pathway in target organs such as the liver, muscles and adipose tissues. The loss of insulin sensitivity is generally associated with persistent hyperglycemia (diabetes), hyperinsulinemia, fatty acids and/or lipid dysregulation which are often prevalent under obesity conditions. Hence, insulin sensitizers are one class of drugs currently employed to treat diabetes and associated metabolic disorders. A number of natural products that act through multiple mechanisms have also been identified to enhance insulin sensitivity in target organs. One group of such compounds that gained interest in recent years are the dietary anthocyanins. Data from their in vitro, in vivo and clinical studies are scrutinized in this communication to show their potential health benefit through ameliorating insulin resistance. Specific mechanism of action ranging from targeting specific signal transduction receptors/enzymes to the general antioxidant and anti-inflammatory mechanisms of insulin resistance are presented.

A pilot plant study using conventional and advanced water treatment processes: Evaluating removal efficiency of indicator compounds representative of pharmaceuticals and personal care products.

PubMed

Zhang, Shuangyi; Gitungo, Stephen; Axe, Lisa; Dyksen, John E; Raczko, Robert F

2016-11-15

With widespread occurrence of pharmaceuticals and personal care products (PPCPs) in the water cycle, their presence in source water has led to the need to better understand their treatability and removal efficiency in treatment processes. Fifteen indicator compounds were identified to represent the large number of PPCPs reported worldwide. Criteria applied to determine the indicator compounds included PPCPs widely used, observed at great frequency in aqueous systems, resistant to treatment, persistent in the environment, and representative of classes of organics. Through a pilot plant investigation to understand the optimal combination of unit process for treating PPCPs, 12 treatment trains with their additive and synergistic contributions were investigated; processes included dissolved air flotation (DAF), pre- and intermediate-ozonation with and without H 2 O 2 , intermediate chlorination, dual media filtration, granular activated carbon (GAC), and UV/H 2 O 2 . Treatment trains that achieved the greatest removals involved 1. DAF followed by intermediate ozonation, dual media filtration, and virgin GAC; 2. pre-ozonation followed by DAF, dual media filtration, and virgin GAC; and, 3. DAF (with either pre- or intermediate oxidation) followed by dual media filtration and UV/H 2 O 2 . Results revealed significant removal efficiencies for virgin GAC (preceded by DAF and intermediate ozonation) and UV/H 2 O 2 with an intensity of 700 mJ/cm 2 , where more than 12 of the compounds were removed by greater than 90%. Reduced PPCP removals were observed with virgin GAC preceded by pre-ozonation and DAF. Intermediate ozonation was more effective than using pre-ozonation, demonstrating the importance of this process targeting PPCPs after treatment of natural organic matter. Removal efficiencies of indicator compounds through ozonation were found to be a function of the O 3 rate constants (k O3 ). For compounds with low O 3 rate constants (k O3  < 10 M -1 s -1 ), H 2 O 2 addition in the O 3 reactor was required. Of the 15 indicator compounds, tri(2-chloroethyl) phosphate (TCEP) and cotinine were observed to be the most recalcitrant. Although UV/H 2 O 2 with elevated intensity (700 mJ/cm 2 ) was effective for PPCP removals, energy requirements far exceed intensities applied for disinfection. Copyright © 2016 Elsevier Ltd. All rights reserved.

Kinetics of natural oxidant demand by permanganate in aquifer solids.

PubMed

Urynowicz, Michael A; Balu, Balamurali; Udayasankar, Umamaheshwari

2008-02-19

During in situ chemical oxidation with permanganate, natural organic matter and other reduced species in the subsurface compete with the target compounds for the available oxidant and can exert a significant natural oxidant demand. This competition between target and nontarget compounds can have a significant impact on the permeation, dispersal, and persistence of permanganate in the subsurface. The kinetics of natural oxidant demand by permanganate was investigated using a composite sample made up of aquifer material collected from three different sites. The study found that although the depletion of organic carbon increased with increased permanganate dosage and increased reaction period, the mass ratio of MnO(4)(-):OC (wt/wt) was relatively constant over time (11.4+/-0.9). The reaction order and rate with respect to permanganate were found to decrease with time suggesting a continuum of reactions with the slower reactions becoming more controlling with time. However, the data also suggests that this continuum of reactions can be simplified into short- and long-term kinetic expressions representing fast and slow reactions. An independent first-order kinetic model with separate fast and slow reaction rate constants was used to successfully describe the complete kinetic expression of natural oxidant demand. The kinetic parameters used in the model are easily determined and can be used to better understand the complex kinetics of natural oxidant demand.

Screening of ground water samples for volatile organic compounds using a portable gas chromatograph

USGS Publications Warehouse

Buchmiller, R.C.

1989-01-01

A portable gas chromatograph was used to screen 32 ground water samples for volatile organic compounds. Seven screened samples were positive; four of the seven samples had volatile organic substances identified by second-column confirmation. Four of the seven positive, screened samples also tested positive in laboratory analyses of duplicate samples. No volatile organic compounds were detected in laboratory analyses of samples that headspace screening indicated to be negative. Samples that contained volatile organic compounds, as identified by laboratory analysis, and that contained a volatile organic compound present in a standard of selected compounds were correctly identified by using the portable gas chromatography. Comparisons of screened-sample data with laboratory data indicate the ability to detect selected volatile organic compounds at concentrations of about 1 microgram per liter in the headspace of water samples by use of a portable gas chromatography. -Author

Equilibrium Passive Sampling of POP in Lipid-Rich and Lean Fish Tissue: Quality Control Using Performance Reference Compounds.

PubMed

Rusina, Tatsiana P; Carlsson, Pernilla; Vrana, Branislav; Smedes, Foppe

2017-10-03

Passive sampling is widely used to measure levels of contaminants in various environmental matrices, including fish tissue. Equilibrium passive sampling (EPS) of persistent organic pollutants (POP) in fish tissue has been hitherto limited to application in lipid-rich tissue. We tested several exposure methods to extend EPS applicability to lean tissue. Thin-film polydimethylsiloxane (PDMS) passive samplers were exposed statically to intact fillet and fish homogenate and dynamically by rolling with cut fillet cubes. The release of performance reference compounds (PRC) dosed to passive samplers prior to exposure was used to monitor the exchange process. The sampler-tissue exchange was isotropic, and PRC were shown to be good indicators of sampler-tissue equilibration status. The dynamic exposures demonstrated equilibrium attainment in less than 2 days for all three tested fish species, including lean fish containing 1% lipid. Lipid-based concentrations derived from EPS were in good agreement with lipid-normalized concentrations obtained using conventional solvent extraction. The developed in-tissue EPS method is robust and has potential for application in chemical monitoring of biota and bioaccumulation studies.

Polycyclic aromatic hydrocarbons - fate and long-range atmospheric transport studied using a global model, EMAC-SVOC

NASA Astrophysics Data System (ADS)

Octaviani, Mega; Tost, Holger; Lammel, Gerhard

2017-04-01

Polycyclic aromatic hydrocarbons (PAHs) are emitted by incomplete combustion from fossil fuel, vehicles, and biomass burning. They may persist in environmental compartments, pose a health hazard and may bio accumulate along food chains. The ECHAM/MESSy Atmospheric Chemistry (EMAC) model had been used to simulate global tropospheric, stratospheric chemistry and climate. In this study, we improve the model to include simulations of the transport and fate of semi-volatile organic compounds (SVOC). The EMAC-SVOC model takes into account essential environmental processes including gas-particle partitioning, dry and wet deposition, chemical and bio-degradation, and volatilization from sea surface, soils, vegetation, and snow. The model was evaluated against observational data in the Arctic, mid-latitudes, and tropics, and further applied to study total environmental lifetime and long-range transport potential (LRTP) of PAHs. We selected four compounds for study, spanning a wide range of volatility, i.e., phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene. Several LRTP indicators were investigated, including the Arctic contamination potential, meridional spreading, and zonal and meridional fluxes to remote regions.

Photodegradation of organic pollutants using N-titanium oxide catalyst.

PubMed

Shinde, S S; Bhosale, C H; Rajpure, K Y

2014-12-01

Photoelectrocatalytic degradation of typical aromatic compounds with persistent reaction rate is studied using thin layers of N-titanium dioxide deposited on transparent and conducting glass substrates. Backside illuminated flow-through parallel plate photoelectrochemical reactors is used and electrical bias for suppressing charge carrier recombination is applied externally. The degradation experiments are performed under solar irradiation with the conditions aimed at reducing contaminant concentrations to maximal tolerated levels as specified under environmental regulations. From the observed COD-time relations, rate constants normalized to unit volume and photocurrent (kinetic parameters), characterizing the efficiency of the electrochemical oxidation process involving photogenerated valence band holes or their immediate reaction products, are calculated and compared to the decrease of optical extinction of the solutions. The parameters for salicylic acid, 4-chlorophenol, benzoic acid and oxalic acid are found to decrease as the main absorption peaks of these substances diminish in due course of degradation reaction. In order to realize a complete mineralization of such compounds, which should be an ultimate aim of water purification, COD and TOC is analyzed. Copyright © 2014 Elsevier B.V. All rights reserved.

[Nutrition and health--toxic substances in food].

PubMed

Rietjens, I M; Alink, G M

2003-11-29

With respect to food, the most important factors causing adverse health effects are: an unbalanced diet, resulting in obesity or vitamin deficiencies, overconsumption of alcohol or fat, the presence of microbial contamination and the presence of natural toxins. Two additional factors, the presence of environmental contaminants and products formed on heating food, may also be of importance. It is generally assumed that, when combined, food-related factors contribute to around 35% of overall cancer incidence. The most important groups of health-threatening compounds to be found in the food chain include natural toxins, such as those produced by plants (phytotoxins), fungi (mycotoxins), marine algae (phycotoxins) and by bacteria, and toxins present in animals for human consumption, especially fish. A second important group of toxic compounds in food consists of environmental contaminants, including heavy metals and persistent organic pollutants, such as dioxins and polychlorinated biphenyls, all of which may unintentionally end up in the food chain. A third group of toxins present in food are those substances produced when food is heated, and include polycyclic aromatic hydrocarbons, heterocyclic amines and acrylamide.

Effects of different factors on photodefluorination of perfluorinated compounds by hydrated electrons in organo-montmorillonite system.

PubMed

Tian, Haoting; Gu, Cheng

2018-01-01

Perfluorinated compounds (PFCs) are considered as the most recalcitrant organic contaminants. Our previous research has shown that PFCs can be completely defluorinated in the UV/organoclay/3-indole acetic acid system, however, the factors that could affect the degradation of PFCs, are still not clear. In this study, we further investigated the effect of different indole derivatives and organo-modified montmorillonite on the degradation of perfluooctanoic acid (PFOA). Based on multiple linear regression analysis, our results clearly indicate that hydrated electron yields of indole derivatives, adsorption of PFOA and indole derivatives on organo-montmorillonite contributed independently to the degradation of PFOA. In addition, the results also show that the presence of humic substance (even at 10 mg C L -1 ) would not significantly suppress the degradation process due to the strong adsorption of humic substance on the organo-montmorillonite surface. This study would provide more information to design an efficient and environment-friendly system for degradation of PFCs, and this technique will have great potential for treatment of persistent contaminants under mild reaction conditions. Copyright © 2017. Published by Elsevier Ltd.

Dyspepsia treatment with Al compounds widely used in clinical practice — an animal model approach

NASA Astrophysics Data System (ADS)

Pinheiro, T.; Canena, J.; Reis, J.; Santos, A. M.; Pinto, A. S.; Quina, M. G.; Reis, M. A.; Alves, L. C.

1996-04-01

The potential toxic effects of Al to organs and tissues used in drugs commonly applied in dyspepsia as therapeutic, have been studied. Brain, liver, kidney and serum samples obtained from Wistar rats treated with two commercial Al complexes were studied and compared with equivalent samples collected from healthy animals receiving a placebo. The major alterations found, connected with the persistent intake of medicaments based on Al compounds, are relative to the accumulation of Al in liver and kidney. Also, the Al levels increase in brain and serum of rats supplemented with one of the Al complexes used. In the liver and kidney samples analyzed alterations in the Cu and Zn content levels were observed. Furthermore, a tendency to the decrease of Fe content in kidney and an increase of the Mn levels in brain is observed. The elemental alterations found are probably related to the intake of the drugs tested and are dependent on the type of the Al complex administered. The results obtained suggest that the long term use of these medicaments in the clinical practice should be thought over.

Method and reaction pathway for selectively oxidizing organic compounds

DOEpatents

Camaioni, Donald M.; Lilga, Michael A.

1998-01-01

A method of selectively oxidizing an organic compound in a single vessel comprises: a) combining an organic compound, an acid solution in which the organic compound is soluble, a compound containing two oxygen atoms bonded to one another, and a metal ion reducing agent capable of reducing one of such oxygen atoms, and thereby forming a mixture; b) reducing the compound containing the two oxygen atoms by reducing one of such oxygen atoms with the metal ion reducing agent to, 1) oxidize the metal ion reducing agent to a higher valence state, and 2) produce an oxygen containing intermediate capable of oxidizing the organic compound; c) reacting the oxygen containing intermediate with the organic compound to oxidize the organic compound into an oxidized organic intermediate, the oxidized organic intermediate having an oxidized carbon atom; d) reacting the oxidized organic intermediate with the acid counter ion and higher valence state metal ion to bond the acid counter ion to the oxidized carbon atom and thereby produce a quantity of an ester incorporating the organic intermediate and acid counter ion; and e) reacting the oxidized organic intermediate with the higher valence state metal ion and water to produce a quantity of alcohol which is less than the quantity of ester, the acid counter ion incorporated in the ester rendering the carbon atom bonded to the counter ion less reactive with the oxygen containing intermediate in the mixture than is the alcohol with the oxygen containing intermediate.

Geogenic organic contaminants in the low-rank coal-bearing Carrizo-Wilcox aquifer of East Texas, USA

NASA Astrophysics Data System (ADS)

Chakraborty, Jayeeta; Varonka, Matthew; Orem, William; Finkelman, Robert B.; Manton, William

2017-06-01

The organic composition of groundwater along the Carrizo-Wilcox aquifer in East Texas (USA), sampled from rural wells in May and September 2015, was examined as part of a larger study of the potential health and environmental effects of organic compounds derived from low-rank coals. The quality of water from the low-rank coal-bearing Carrizo-Wilcox aquifer is a potential environmental concern and no detailed studies of the organic compounds in this aquifer have been published. Organic compounds identified in the water samples included: aliphatics and their fatty acid derivatives, phenols, biphenyls, N-, O-, and S-containing heterocyclic compounds, polycyclic aromatic hydrocarbons (PAHs), aromatic amines, and phthalates. Many of the identified organic compounds (aliphatics, phenols, heterocyclic compounds, PAHs) are geogenic and originated from groundwater leaching of young and unmetamorphosed low-rank coals. Estimated concentrations of individual compounds ranged from about 3.9 to 0.01 μg/L. In many rural areas in East Texas, coal strata provide aquifers for drinking water wells. Organic compounds observed in groundwater are likely to be present in drinking water supplied from wells that penetrate the coal. Some of the organic compounds identified in the water samples are potentially toxic to humans, but at the estimated levels in these samples, the compounds are unlikely to cause acute health problems. The human health effects of low-level chronic exposure to coal-derived organic compounds in drinking water in East Texas are currently unknown, and continuing studies will evaluate possible toxicity.

Gone or just out of sight? The apparent disappearance of aromatic litter components in soils

NASA Astrophysics Data System (ADS)

Klotzbücher, Thimo; Kalbitz, Karsten; Cerli, Chiara; Hernes, Peter J.; Kaiser, Klaus

2016-07-01

Uncertainties concerning stabilization of organic compounds in soil limit our basic understanding on soil organic matter (SOM) formation and our ability to model and manage effects of global change on SOM stocks. One controversially debated aspect is the contribution of aromatic litter components, such as lignin and tannins, to stable SOM forms. In the present opinion paper, we summarize and discuss the inconsistencies and propose research options to clear them. Lignin degradation takes place stepwise, starting with (i) depolymerization and followed by (ii) transformation of the water-soluble depolymerization products. The long-term fate of the depolymerization products and other soluble aromatics, e.g., tannins, in the mineral soils is still a mystery. Research on dissolved organic matter (DOM) composition and fluxes indicates dissolved aromatics are important precursors of stable SOM attached to mineral surfaces and persist in soils for centuries to millennia. Evidence comes from flux analyses in soil profiles, biodegradation assays, and sorption experiments. In contrast, studies on composition of mineral-associated SOM indicate the prevalence of non-aromatic microbial-derived compounds. Other studies suggest the turnover of lignin in soil can be faster than the turnover of bulk SOM. Mechanisms that can explain the apparent fast disappearance of lignin in mineral soils are, however, not yet identified. The contradictions might be explained by analytical problems. Commonly used methods probably detect only a fraction of the aromatics stored in the mineral soil. Careful data interpretation, critical assessment of analytical limitations, and combined studies on DOM and solid-phase SOM could thus be ways to unveil the issues.

Gone or just out of sight? The apparent disappearance of aromatic litter components in soils

NASA Astrophysics Data System (ADS)

Klotzbücher, Thimo; Kalbitz, Karsten; Cerli, Chiara; Hernes, Peter; Kaiser, Klaus

2016-04-01

Uncertainties concerning stabilization of organic compounds in soil limit our basic understanding on soil organic matter (SOM) formation and our ability to model and manage effects of global change on SOM stocks. One controversially debated aspect is the contribution of aromatic litter components, such as lignin and tannins, to stable SOM forms. Here we summarize and discuss the inconsistencies and propose research options to clear them. Lignin degradation takes place step-wise, starting with (i) depolymerisation, followed by (ii) transformation of the water-soluble depolymerization products. The long-term fate of the depolymerization products and other soluble aromatics, e.g., tannins, in the mineral soils is still a mystery. Research on dissolved organic matter (DOM) composition and fluxes indicates dissolved aromatics are important precursors of stable SOM attached to mineral surfaces and persist in soils for centuries to millennia. Evidence comes from flux analyses in soil profiles, biodegradation assays, and sorption experiments. In contrast, studies on composition of mineral-associated SOM indicate the prevalence of non-aromatic microbial-derived compounds. Other studies suggest the turnover of lignin in soil can be faster than the turnover of bulk SOM. Mechanisms that can explain the apparent fast disappearance of lignin in mineral soils are, however, not yet identified. The contradictions might be explained by analytical problems. Commonly used methods probably detect only a fraction of the aromatics stored in the mineral soil. Careful data interpretation, critical assessment of analytical limitations, and combined studies on DOM and solid-phase SOM could thus be ways to unveil the issues.

Protective effects of levamisole, acetylsalicylic acid, and α-tocopherol against dioxin toxicity measured as the expression of AhR and COX-2 in a chicken embryo model.

PubMed

Gostomska-Pampuch, Kinga; Ostrowska, Alicja; Kuropka, Piotr; Dobrzyński, Maciej; Ziółkowski, Piotr; Kowalczyk, Artur; Łukaszewicz, Ewa; Gamian, Andrzej; Całkosiński, Ireneusz

2017-04-01

Polychlorinated dibenzo-p-dioxins and dibenzofurans (dioxins) are classed as persistent organic pollutants and have adverse effects on multiple functions within the body. Dioxins are known carcinogens, immunotoxins, and teratogens. Dioxins are transformed in vivo, and interactions between the products and the aryl hydrocarbon receptor (AhR) lead to the formation of proinflammatory and toxic metabolites. The aim of this study was to determine whether α-tocopherol (vitamin E), acetylsalicylic acid (ASA), and levamisole can decrease the amount of damage caused by dioxins. Fertile Hubbard Flex commercial line chicken eggs were injected with solutions containing 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or containing TCDD and the test compounds. The chicken embryos and organs were analyzed after 7 and 13 days. The levels at which AhR and cyclooxygenase-2 (COX-2) proteins (which are induced during inflammation) were expressed were evaluated by performing immunohistochemical analyses on embryos treated with TCDD alone or with TCDD and the test compounds. TCDD caused developmental disorders and increased AhR and COX-2 expression in the chicken embryo tissues. Vitamin E, levamisole, ASA, and ASA plus vitamin E inhibited AhR and COX-2 expression in embryos after 7 days and decreased AhR and COX-2 expression in embryos after 13 days. ASA, levamisole, and ASA plus vitamin E weakened the immune response and prevented multiple organ changes. Vitamin E was not fully protective against developmental changes in the embryos.

A REVIEW OF BIOACCUMULATION MODELING APPROACHES FOR PERSISTENT ORGANIC POLLUTANTS

EPA Science Inventory

Persistent organic pollutants and mercury are likely to bioaccumulate in biological components of the environment, including fish and wildlife. The complex and long-term dynamics involved with bioaccumulation are often represented with models. Current scientific developments in t...

The Effects of Organic Pollutants in Soil on Human Health

NASA Astrophysics Data System (ADS)

Burgess, Lynn

2013-04-01

The soil has always been depository of the organic chemicals produced naturally or anthropogenically. Soil contamination is a serious human and environmental problem. A large body of evidence has shown the risks of adverse health effects with the exposure to contaminated soil due to the large quantities of organic chemicals used in agriculture and urban areas that have a legacy of environmental pollution linked to industrial activities, coal burning, motor vehicle emissions, waste incineration and waste dumping. In agricultural areas, because of the effort to provide adequate quantities of agricultural products, farmers have been using an increasing amount of organic chemicals, but the resulting pollution has enormous potential for environmental damage. The types of organic pollutants commonly found in soils are polychlorinated biphenyls, polybrominated biphenyls, polychlorinated dibenzofurans, polycyclic aromatic hydrocarbons, organophosphorus and carbamate insecticides, herbicides and organic fuels, especially gasoline and diesel. Another source of soil pollution is the complex mixture of organic chemicals, metals and microorganisms in the effluent from septic systems, animal wastes and other sources of biowaste. The soils of the world are a vast mixture of chemicals and although conditions are such that an individual is rarely exposed to a single compound, the great majority of people are exposed to a vast chemical mixture of organics, their metabolites, and other compounds at low concentrations Human exposure to organic pollutants in the soil is an area of toxicology that is very difficult to study due to the low concentration of the pollutants. The toxicological studies of single organic pollutants found in soils are limited and research on the metabolites and of chemical mixtures is very limited. The majority of toxicological studies are conducted at relatively high doses and for short periods of exposure. This makes the application of this data to exposure from soil very difficult, with the exposure from soil usually being chronic and at very low concentrations. The vastness of the soil has led to the dilution of these pollutants and most of the pollutants remain on or near the surface of the soil unless they have moved by the action of water, organisms, or mechanical mixing. This dilution has reduced the toxicity of these pollutants but the unknown factor is the action of the soil, its chemistry, and the combined action of all the microorganisms, plants, and invertebrates that live in the soil. This biological action combined with the influences of the soil components has the potential of creating new metabolites and chemicals. Toxicologists needs expand their studies to include the persistent organic pollutants and the organic pollutants that can bioaccumulate in organisms. We do not know if the addition of organics chemicals to the soil is creating very toxic xenobiotics and at very low concentrations but with important health effects to humans and other organisms. These unknown compounds could be accumulating in plants that we use for food or as forage for our livestock, then bioaccumulating in the livestock and then on into us.

Neurotoxicity of Persistent Organic Pollutants: Possible Mode(s) of Action and Further Considerations

PubMed Central

Kodavanti, Prasada Rao S.

2005-01-01

Persistent organic pollutants (POPs) are long-lived toxic organic compounds and are of major concern for human and ecosystem health. Although the use of most POPs is banned in most countries, some organochlorine pesticides are still being used in several parts of the world. Although environmental levels of some POPs such as polychlorinated biphenyls (PCBs) have declined, newly emerging POPs such as polybrominated diphenyl ethers (PBDEs) have been increasing considerably. Exposure to POPs has been associated with a wide spectrum of effects including reproductive, developmental, immunologic, carcinogenic, and neurotoxic effects. It is of particular concern that neurotoxic effects of some POPs have been observed in humans at low environmental concentrations. This review focuses on PCBs as a representative chemical class of POPs and discusses the possible mode(s) of action for the neurotoxic effects with emphasis on comparing dose-response and structure-activity relationships (SAR) with other structurally related chemicals. There is sufficient epidemiological and experimental evidence showing that PCB exposure is associated with motor and cognitive deficits in humans and animal models. Although several potential mode(s) of actions were postulated for PCB-induced neurotoxic effects, changes in neurotransmitter systems, altered intracellular signalling processes, and thyroid hormone imbalance are predominant ones. These three potential mechanisms are discussed in detail in vitro and in vivo. In addition, SAR was conducted on other structurally similar chemicals to see if they have a common mode(s) of action. Relative potency factors for several of these POPs were calculated based on their effects on intracellular signalling processes. This is a comprehensive review comparing molecular effects at the cellular level to the neurotoxic effects seen in the whole animal for environmentally relevant POPs. PMID:18648619

Synthetic musk fragrances in environmental Standard Reference Materials.

PubMed

Peck, Aaron M; Kucklick, John R; Schantz, Michele M

2007-04-01

Synthetic musk fragrances have been measured in water, air, sediments, sewage sludge, and biota worldwide. As the study of the environmental fate and impacts of these compounds progresses, the need for Standard Reference Materials (SRMs) for these compounds to facilitate analytical method improvement and interlaboratory comparisons becomes increasingly important. The National Institute of Standards and Technology (NIST) issues environmental matrix SRMs with certified concentrations for a variety of persistent organic pollutants including polycyclic aromatic hydrocarbons (PAHs), chlorinated pesticides, and polychlorinated biphenyl congeners (PCBs). Until now synthetic musk fragrance concentrations have not been reported in NIST SRMs. The objective of this study was to provide reference values for several commonly detected synthetic musk fragrances in several NIST natural matrix SRMs. In this study five polycyclic musk fragrances [HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-gamma-2-benzopyran), AHTN (7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene), ADBI (4-acetyl-1,1-dimethyl-6-tert-butylindane), AHMI (6-acetyl-1,1,2,3,3,5-hexamethylindane), and ATII (5-acetyl-1,1,2,6-tetramethyl-3-isopropylindane] and two nitro musk fragrances [musk xylene (1-tert-butyl-3,5-dimethyl-2,4,6-trinitrobenzene) and musk ketone (4-tert-butyl-3,5-dinitro-2,6-dimethylacetophenone)] were measured in selected environmental SRMs. Gas chromatography-electron impact mass spectrometry (GC/EI-MS) was used for all analyses. HHCB was the most frequently detected synthetic musk fragrance and was detected in SRM 2585 Organic Contaminants in House Dust, SRM 2781 Domestic Sludge, SRM 1974b Organics in Mussel Tissue (Mytilus edulis), and SRM 1947 Lake Michigan Fish Tissue. It was not detected in SRM 1946 Lake Superior Fish Tissue or SRM 1945 Organics in Whale Blubber. Concentrations of HHCB in these SRMs ranged from 1.12 ng/g in SRM 1947 to 92,901 ng/g in SRM 2781. All of the polycyclic musk fragrances were detected in SRM 2781 and all of the target compounds were detected in SRM 2585.

Fate and transport of selected estrogen compounds in Hawaii soils: effect of soil type and macropores.

PubMed

D'Alessio, Matteo; Vasudevan, Dharni; Lichwa, Joseph; Mohanty, Sanjay K; Ray, Chittaranjan

2014-10-01

The fate and transport of estrogen compounds in the environment is of increasing concern due to their potential impact on freshwater organisms, ecosystems and human health. The behavior of these compounds in batch experiments suggests low mobility, while field studies indicate the persistence of estrogen compounds in the soil with the possibility of migration to surface water as well as groundwater. To better understand the movement of these chemicals through soils, we examined their transport in three different Hawaiian soils and two aqueous matrices. The three different soils used were an Oxisol, a Mollisol and a cinder, characterized by different mineralogical properties and collected at depths of 60-90 cm and 210-240 cm. Two liquid matrices were used; deionized (DI) water containing calcium chloride (CaCl2), and recycled water collected from a wastewater treatment facility. The experiments were conducted in packed and structured columns. Non-equilibrium conditions were observed during the study, especially in the structured soil. This is believed to be primarily related to the presence of macropores in the soil. The presence of macropores resulted in reduced contact time between soil and estrogens, which facilitated their transport. We found that the organic carbon content and mineralogical composition of the soils had a profound effect on the transport of the estrogens. The mobility of estrone (E1) and 17β-estradiol (E2) was greater in cinder than in the other soils. In column experiments with recycled water, earlier breakthrough peaks and longer tails of estrogens were produced compared to those observed using DI water. The use of recycled water for agricultural purposes and the siting of septic tanks and cesspools should be critically reviewed in light of these findings, especially in areas where groundwater is the primary source of potable water, such as Hawaii. Copyright © 2014 Elsevier B.V. All rights reserved.

Fate and transport of selected estrogen compounds in Hawaii soils: Effect of soil type and macropores

NASA Astrophysics Data System (ADS)

D'Alessio, Matteo; Vasudevan, Dharni; Lichwa, Joseph; Mohanty, Sanjay K.; Ray, Chittaranjan

2014-10-01

The fate and transport of estrogen compounds in the environment is of increasing concern due to their potential impact on freshwater organisms, ecosystems and human health. The behavior of these compounds in batch experiments suggests low mobility, while field studies indicate the persistence of estrogen compounds in the soil with the possibility of migration to surface water as well as groundwater. To better understand the movement of these chemicals through soils, we examined their transport in three different Hawaiian soils and two aqueous matrices. The three different soils used were an Oxisol, a Mollisol and a cinder, characterized by different mineralogical properties and collected at depths of 60-90 cm and 210-240 cm. Two liquid matrices were used; deionized (DI) water containing calcium chloride (CaCl2), and recycled water collected from a wastewater treatment facility. The experiments were conducted in packed and structured columns. Non-equilibrium conditions were observed during the study, especially in the structured soil. This is believed to be primarily related to the presence of macropores in the soil. The presence of macropores resulted in reduced contact time between soil and estrogens, which facilitated their transport. We found that the organic carbon content and mineralogical composition of the soils had a profound effect on the transport of the estrogens. The mobility of estrone (E1) and 17β-estradiol (E2) was greater in cinder than in the other soils. In column experiments with recycled water, earlier breakthrough peaks and longer tails of estrogens were produced compared to those observed using DI water. The use of recycled water for agricultural purposes and the siting of septic tanks and cesspools should be critically reviewed in light of these findings, especially in areas where groundwater is the primary source of potable water, such as Hawaii.

Cancer and non-cancer health effects from food contaminant exposures for children and adults in California: a risk assessment

PubMed Central

2012-01-01

Background In the absence of current cumulative dietary exposure assessments, this analysis was conducted to estimate exposure to multiple dietary contaminants for children, who are more vulnerable to toxic exposure than adults. Methods We estimated exposure to multiple food contaminants based on dietary data from preschool-age children (2–4 years, n=207), school-age children (5–7 years, n=157), parents of young children (n=446), and older adults (n=149). We compared exposure estimates for eleven toxic compounds (acrylamide, arsenic, lead, mercury, chlorpyrifos, permethrin, endosulfan, dieldrin, chlordane, DDE, and dioxin) based on self-reported food frequency data by age group. To determine if cancer and non-cancer benchmark levels were exceeded, chemical levels in food were derived from publicly available databases including the Total Diet Study. Results Cancer benchmark levels were exceeded by all children (100%) for arsenic, dieldrin, DDE, and dioxins. Non-cancer benchmarks were exceeded by >95% of preschool-age children for acrylamide and by 10% of preschool-age children for mercury. Preschool-age children had significantly higher estimated intakes of 6 of 11 compounds compared to school-age children (p<0.0001 to p=0.02). Based on self-reported dietary data, the greatest exposure to pesticides from foods included in this analysis were tomatoes, peaches, apples, peppers, grapes, lettuce, broccoli, strawberries, spinach, dairy, pears, green beans, and celery. Conclusions Dietary strategies to reduce exposure to toxic compounds for which cancer and non-cancer benchmarks are exceeded by children vary by compound. These strategies include consuming organically produced dairy and selected fruits and vegetables to reduce pesticide intake, consuming less animal foods (meat, dairy, and fish) to reduce intake of persistent organic pollutants and metals, and consuming lower quantities of chips, cereal, crackers, and other processed carbohydrate foods to reduce acrylamide intake. PMID:23140444

Persistent organic pollutants in Mediterranean seawater and processes affecting their accumulation in plankton.

PubMed

Berrojalbiz, Naiara; Dachs, Jordi; Del Vento, Sabino; Ojeda, María José; Valle, María Carmen; Castro-Jiménez, Javier; Mariani, Giulio; Wollgast, Jan; Hanke, Georg

2011-05-15

The Mediterranean and Black Seas are unique marine environments subject to important anthropogenic pressures due to riverine and atmospheric inputs of organic pollutants. Here, we report the results obtained during two east-west sampling cruises in June 2006 and May 2007 from Barcelona to Istanbul and Alexandria, respectively, where water and plankton samples were collected simultaneously. Both matrixes were analyzed for hexaclorochyclohexanes (HCHs), hexachlorobenzene (HCB), and 41 polychlorinated biphenyl (PCB) congeners. The comparison of the measured HCB and HCHs concentrations with previously reported dissolved phase concentrations suggests a temporal decline in their concentrations since the 1990s. On the contrary, PCB seawater concentrations did not exhibit such a decline, but show a significant spatial variability in dissolved concentrations with lower levels in the open Western and South Eastern Mediterranean, and higher concentrations in the Black, Marmara, and Aegean Seas and Sicilian Strait. PCB and OCPs (organochlorine pesticides) concentrations in plankton were higher at lower plankton biomass, but the intensity of this trend depended on the compound hydrophobicity (K(OW)). For the more persistent PCBs and HCB, the observed dependence of POP concentrations in plankton versus biomass can be explained by interactions between air-water exchange, particle settling, and/or bioaccumulation processes, whereas degradation processes occurring in the photic zone drive the trends shown by the more labile HCHs. The results presented here provide clear evidence of the important physical and biogeochemical controls on POP occurrence in the marine environment.

Removal of persistent organic pollutants from micro-polluted drinking water by triolein embedded absorbent.

PubMed

Liu, Huijuan; Ru, Jia; Qu, Jiuhui; Dai, Ruihua; Wang, Zijian; Hu, Chun

2009-06-01

A new biomimetic absorbent, cellulose acetate (CA) embedded with triolein (CA-triolein), was prepared and applied for the removal of persistent organic pollutants (POPs) from micro-polluted aqueous solution. The comparison of CA-triolein, CA and granular activated carbon (GAC) for dieldrin removal was investigated. Results showed that CA-triolein absorbent gave a lowest residual concentration after 24 h although GAC had high removal rate in the first 4 h adsorption. Then the removal efficiency of mixed POPs (e.g. aldrin, dieldrin, endrin and heptachlor epoxide), absorption isotherm, absorbent regeneration and initial column experiments of CA-triolein were studied in detail. The linear absorption isotherm and the independent absorption in binary isotherm indicated that the selected POPs are mainly absorbed onto CA-triolein absorbent by a partition mechanism. The absorption constant, K, was closely related to the hydrophobic property of the compound. Thermodynamic calculations showed that the absorption was spontaneous, with a high affinity and the absorption was an endothermic reaction. Rinsing with hexane the CA-triolein absorbent can be regenerated after absorption of POPs. No significant decrease in the dieldrin removal efficiency was observed even when the absorption-regeneration process was repeated for five times. The results of initial column experiments showed that the CA-triolein absorbent did not reach the breakthrough point at a breakthrough empty-bed volume (BV) of 3200 when the influent concentration was 1-1.5 microg/L and the empty-bed contact time (EBCT) was 20 min.

Estimation of physicochemical properties of 2-ethylhexyl-4-methoxycinnamate (EHMC) degradation products and their toxicological evaluation.

PubMed

Gackowska, Alicja; Studziński, Waldemar; Kudlek, Edyta; Dudziak, Mariusz; Gaca, Jerzy

2018-06-01

The organic UV filters, commonly used in personal protection products, are of concern because of their potential risk to aquatic ecosystems and living organisms. One of UV filters is ethylhexyl-4-methoxycinnamate (EHMC) acid. Studies have shown that, in the presence of oxidizing and chlorinating factors, EHMC forms a series of products with different properties than the substrate. In this study, the toxicities of EHMC and its transformation/degradation products formed under the influence of NaOCl/UV and H 2 O 2 /UV systems in the water medium were tested using Microtox® bioassay and by observation of mortality of juvenile crustaceans Daphnia magna and Artemia Salina. We have observed that oxidation and chlorination products of EHMC show significantly higher toxicity than EHMC alone. The toxicity of chemicals is related to their physicochemical characteristic such as lipophilicity and substituent groups. With the increase in lipophilicity of products, expressed as log K OW , the toxicity (EC 50 ) increases. On the basis of physicochemical properties such as vapour pressure (VP), solubility (S), octanol-water partition coefficient (K OW ), bioconcentration factor (BCF) and half-lives, the overall persistence (P OV ) and long-range transport potential (LRTP) of all the products and EHMC were calculated. It was shown that the most persistent and traveling on the long distances in environment are methoxyphenol chloroderivatives, then methoxybenzene chloroderivatives, EHMC chloroderivatives, methoxybenzaldehyde chloroderivatives and methoxycinnamate acid chloroderivatives. These compounds are also characterised by high toxicity.

Reducing emissions of persistent organic pollutants from a diesel engine by fueling with water-containing butanol diesel blends.

PubMed

Chang, Yu-Cheng; Lee, Wen-Jhy; Yang, Hsi-Hsien; Wang, Lin-Chi; Lu, Jau-Huai; Tsai, Ying I; Cheng, Man-Ting; Young, Li-Hao; Chiang, Chia-Jui

2014-05-20

The manufacture of water-containing butanol diesel blends requires no excess dehydration and surfactant addition. Therefore, compared with the manufacture of conventional bio-alcohols, the energy consumption for the manufacture of water-containing butanol diesel blends is reduced, and the costs are lowered. In this study, we verified that using water-containing butanol diesel blends not only solves the tradeoff problem between nitrogen oxides (NOx) and particulate matter emissions from diesel engines, but it also reduces the emissions of persistent organic pollutants (POPs), including polycyclic aromatic hydrocarbons, polychlorinated dibenzo-p-dioxins and dibenzofurans, polychlorinated biphenyls, polychlorinated diphenyl ethers, polybrominated dibenzo-p-dioxins and dibenzofurans, polybrominated biphenyls and polybrominated diphenyl ethers. After using blends of B2 with 10% and 20% water-containing butanol, the POP emission factors were decreased by amounts in the range of 22.6%-42.3% and 38.0%-65.5% on a mass basis, as well as 18.7%-78.1% and 51.0%-84.9% on a toxicity basis. The addition of water-containing butanol introduced a lower content of aromatic compounds and most importantly, lead to more complete combustion, thus resulting in a great reduction in the POP emissions. Not only did the self-provided oxygen of butanol promote complete oxidation but also the water content in butanol diesel blends could cause a microexplosion mechanism, which provided a better turbulence and well-mixed environment for complete combustion.

Comparison of glacial and non-glacial-fed streams to evaluate the loading of persistent organic pollutants through seasonal snow/ice melt.

PubMed

Bizzotto, E C; Villa, S; Vaj, C; Vighi, M

2009-02-01

The release of persistent organic pollutants (PCBs, HCB, HCHs and DDTs) accumulated in Alpine glaciers, was studied during spring-summer 2006 on the Frodolfo glacial-fed stream (Italian Alps). Samples were also taken on a non-glacial stream in the same valley, to compare POP contribution from different water sources (glacier ice, recent snow and spring). In late spring and early summer (May, June) recent snow melting is the most important process. POP contamination is more affected by local emissions and transport, and comparable levels have been measured in both streams for all studied compounds. In late summer and autumn (July-October), the contribution of ice melting strongly increases. In the glacial-fed stream the concentration of chlorinated pesticides (HCHs and DDTs) is about one order of magnitude higher than in the non-glacial-fed. A different behaviour was observed for PCBs, characterised by a peak in June showing, in both streams, concentrations three orders of magnitude higher than the background levels measured in May and in October. This result should be attributed to local emissions rather than long range atmospheric transport (LRAT). This hypothesis is supported by the PCB congener profile in June strictly comparable to the most commonly used Aroclor technical mixtures. The different seasonal behaviour observed for the different groups of chemicals indicates the POP loading in glacial streams is a combined role of long range atmospheric transport and local emission.

Bioaccumulation and biomagnification of persistent organic pollutants in Indo-Pacific humpback dolphins (Sousa chinensis) from the Pearl River Estuary, China.

PubMed

Gui, Duan; Yu, Riqing; He, Xuan; Tu, Qin; Chen, Laiguo; Wu, Yuping

2014-11-01

Indo-Pacific humpback dolphins (Sousa chinensis) are apex predators in the Pearl River Estuary waters (PRE) of China. PCBs, DDTs and other organochlorine pesticides (OCPs) (e.g., HCHs, HCB, mirex and dieldrin) were analysed in blubber samples of 45 dolphins and 10 prey fishes of S. chinensis collected from 2004 to 2013 in the PRE region to investigate the bioaccumulation and potential biomagnification of persistent organic pollutants (POPs). DDTs were the most abundant residue in the dolphins, with an average of 6,2700 ng g(-1) wet weight (ww), followed by PCBs (average: 1,790 ng g(-1) ww) and other OCPs including ∑HCHs, mirex, endrin, ∑chlordanes, HCB, dieldrin, aldrin, heptachlor, and pentachlorobenzene. The concentrations of PCBs and DDTs in male dolphins significantly increased with age and length. In contrast, female dolphins did not show obvious bioaccumulation trends with age and body length, possibly due to the lactational and parturitional transfer of these compounds. Compared with the POP residues in the prey fishes, the concentrations of PCBs, DDTs, and HCHs in the dolphin blubber increased by factors of 99, 212, and 5, respectively, whereas the residue levels of the other OCPs increased 2-185 times, indicating a potentially significant biomagnification in the top predators. The potential biomagnification factors calculated for most POPs were significantly higher than those in the cetacean species from other regions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Inorganic Carbon and pH in the Gulf of Mexico: Understanding the Deepwater Horizon Region

NASA Astrophysics Data System (ADS)

Young, J.; Yvon-Lewis, S. A.; Bianchi, T. S.; Shields, M. R.; Du, M.

2014-12-01

The breakdown and respiration of oil compounds may contribute to the dissolved inorganic carbon (DIC) pool and thus ocean acidification. The Gulf of Mexico (GOM) has an abundance of natural seeps as well as numerous man-made structures that could provide a source of hydrocarbons to the water column. Samples of seawater were collected on the first GISR (Gulf Integrated Spill Research) cruise (G01) during the first week of July 2012. This cruise covered an area of ~1360 km2 roughly centered on the site of the Deepwater Horizon disaster. Alkalinity profiles for the southeastern most stations indicate lower (~100 μmol/kg) alkalinities at depth when compared to other stations sampled. This results in calculated pHs that are ~0.5 units lower at depth than they are at the other stations. Another group of stations show increased DIC concentrations on the order of 100-150 μmol/kg higher than average at depths at 800 m and 1200 m leading to calculated pHs about 0.2 to 0.4 below average for those depths in all of the stations sampled. These features may or may not be persistent in this region, and the elevated DIC concentrations may be related to organic matter (petroleum or other) oxidation. Samples were collected from this same region 2 years later (June 2014) and the persistence of these features will be discussed in the context of linkages with organic carbon respiration and low pHs.

Organic micro-pollutants in a karst system during low and high flow periods, results of a two-year study

NASA Astrophysics Data System (ADS)

Reh, Roland; Licha, Tobias; Geyer, Tobias; Nödler, Karsten; Sauter, Martin

2013-04-01

Fifty-four different organic micro-pollutants (OMPs) including pharmaceuticals, pesticides, corrosion inhibitors and other typical wastewater compounds such as caffeine are repeatedly analyzed in approximately fifty groundwater observation points in a complex faulted and fractured carbonate aquifer system consisting of three main spring catchment areas. The study area is characterized as well by the influence of an urban area with industrial sites and waste disposals as by surrounding agricultural uses. With the applied HPLC-MS/MS method (Nödler et al., 2010), achieving method quantification limits (MQL) of 1.8 - 28 ng L-1, forty-four of the OMPs are detected in groundwater. Indicating a subsurface water divide, OMPs distinguish between the North and the South main spring areas with respect to the number of detected OMPs, OMP combinations, occurrence of special compounds like tamoxifen and concentrations of triazoles and triazines. Regarding the vertical distribution in the aquifer system upper aquifers exhibit a higher number and higher seasonal variety of OMPs than the lower aquifer and the main spring areas. In addition to triazines and triazoles the anti-epileptic drug carbamazepine and the analgesic drug phenazone are the most frequently detected compounds. The detection of the estrogen antagonist tamoxifen in a groundwater flow system is reported for the first time. Defined combinations of OMPs occur repeatedly in the same observation wells and allow to distinguish different input functions. The comparison of detection frequency with the number of prescribed doses gives information about the specific persistance of pharmaceuticals. A disused waste disposal is identified as input area for triazines. Additional input of triazines in the agricultural areas may be indicated by different fractions of atrazine and its degradation products. Due to prohibition of atrazine as herbicide since 1992 the occurrence of OMPs in the lower aquifer, solely limited to atrazine and desethylatrazine, indicates limited aquifer connections and demonstrates a residence time of several years for vertical transport into the deep aquifer. Phenazone originates also from a disused waste disposal and is showing a persistency for more than three decades under the observed redox conditions. References Nödler K, Licha T, Bester K, Sauter M. Development of a multi-residue analytical method, based on liquid chromatography-tandem mass spectrometry, for the simultaneous determination of 46 micro-contaminants in aqueous samples. Journal of Chromatography A 2010;1217(42), 6511-6521. Reh R, Licha T, Geyer T, Nödler, K.,Sauter M. Occurrence and spatial distribution of organic micro-pollutants in a complex hydrogeological karst system during low flow and high flow periods, results of a two-year study. Science of The Total Environment 2013, 443,438-445, 10.1016/j.scitotenv.2012.11.005.

Historic and newer persistent organic pollutants in food

USDA-ARS?s Scientific Manuscript database

This book chapter reviews the literature published over the past five years with regard to the concentrations of historic and newly-listed persistent organic pollutants (POPs) in foods. The chemical classes selected for this review include historic POPs (dioxins, polychlorinated biphenyls, and DDT) ...

Removal of organic compounds from shale gas flowback water.

PubMed

Butkovskyi, Andrii; Faber, Ann-Hélène; Wang, Yue; Grolle, Katja; Hofman-Caris, Roberta; Bruning, Harry; Van Wezel, Annemarie P; Rijnaarts, Huub H M

2018-07-01

Ozonation, sorption to granular activated carbon and aerobic degradation were compared as potential treatment methods for removal of dissolved organic carbon (DOC) fractions and selected organic compounds from shale gas flowback water after pre-treatment in dissolved air flotation unit. Flowback water was characterised by high chemical oxygen demand and DOC. Low molecular weight (LMW) acids and neutral compounds were the most abundant organic fractions, corresponding to 47% and 35% of DOC respectively. Ozonation did not change distribution of organic carbon fractions and concentrations of detected individual organic compounds significantly. Sorption to activated carbon targeted removal of individual organic compounds with molecular weight >115 Da, whereas LMW compounds remained largely unaffected. Aerobic degradation was responsible for removal of LMW compounds and partial ammonium removal, whereas formation of intermediates with molecular weight of 200-350 Da was observed. Combination of aerobic degradation for LMW organics removal with adsorption to activated carbon for removal of non-biodegradable organics is proposed to be implemented between pre-treatment (dissolved air floatation) and desalination (thermal or membrane desalination) steps. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

Porta, Miquel; Facultat de Medicina, Universitat Autonoma de Barcelona; CIBER en Epidemiologia y Salud Publica

Background: The relationships between social factors and body concentrations of environmental chemical agents are unknown in many human populations. Some chemical compounds may play an etiopathogenic role in pancreatic cancer. Objective: To analyze the relationships between occupational social class and serum concentrations of seven selected organochlorine compounds (OCs) in exocrine pancreatic cancer: dichlorodiphenyltrichloroethane (p,p'-DDT), dichlorodiphenyldichloroethene (p,p'-DDE), 3 polychlorinated biphenyls (PCBs), hexachlorobenzene, and {beta}-hexachlorocyclohexane. Methods: Incident cases of exocrine pancreatic cancer were prospectively identified, and interviewed face-to-face during hospital admission (n=135). Serum concentrations of OCs were analyzed by high-resolution gas chromatography with electron-capture detection. Social class was classified according to occupation.more » Results: Multivariate-adjusted concentrations of all seven compounds were higher in occupational social classes IV-V (the less affluent) than in classes I-II; they were higher as well in class III than in classes I-II for four compounds. Concentrations of six OCs were higher in manual workers than in non-manual workers (p<0.05 for PCBs). Social class explained statistically between 3.7% and 5.7% of the variability in concentrations of PCBs, and 2% or less variability in the other OCs. Conclusions: Concentrations of most OCs were higher in the less affluent occupational social classes. In pancreatic cancer the putative causal role of these persistent organic pollutants may not be independent of social class. There is a need to integrate evidence on the contribution of different social processes and environmental chemical exposures to the etiology of pancreatic and other cancers.« less

Antimicrobial resistance and its association with tolerance to heavy metals in agriculture production.

PubMed

Yu, Zhongyi; Gunn, Lynda; Wall, Patrick; Fanning, Séamus

2017-06-01

Antimicrobial resistance is a recognized public health challenge that since its emergence limits the therapeutic options available to veterinarians and clinicians alike, when treatment is warranted. This development is further compounded by the paucity of new antibiotics. The agri-food industry benefits from the availability of antimicrobial compounds for food-animal production and crop protection. Nonetheless, their improper use can result in the selection for bacteria that are phenotypically resistant to these compounds. Another class of agents used in agriculture includes various cationic metals that can be included in animal diets as nutritional supplements or spread on pastures to support crop growth and protection. Heavy metals, in particular, are giving rise to concerns among public health professionals, as they can persist in the environment remaining stable for prolonged periods. Moreover, bacteria can also exhibit resistance to these chemical elements and the genes encoding this phenotype can be physically localized to plasmids that may also contain one or more antimicrobial resistance-encoding gene(s). This paper reviews our current understanding of the role that bacteria play in expressing resistance to heavy metals. It will describe how heavy metals are used in agri-food production, and explore evidence available to link resistance to heavy metals and antimicrobial compounds. In addition, possible solutions to reduce the impact of heavy metal resistance are also discussed, including using organic minerals and reducing the level of trace minerals in animal feed rations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Aquatic metabolism of 3-trifluoromethyl-4-nitrophenol

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

Fathulla, R.N.; Conteh, A.R.; Pogosyan, A.I.

1995-12-01

Aerobic and anaerobic aquatic metabolism of {sup 14}C-3-trifluoromethyl-4-nitrophenol ({sup 14}C-TFM) in lake water and sediment samples from Black River, Michigan, was investigated following Federal Insecticide, Fungicide, and Rodenticide Act EPA guidelines and according to Good Laboratory Practices. The half-life of {sup 14}C-TFM under anaerobic conditions was 2.1 days versus 5.5 days under aerobic conditions. After 30 days of anaerobic incubation, 93.5% of applied TFM was transferred to 4- amino-3-(trifluoromethyl) phenol (reduced TFM) and only 5.1% was incorporated into sediment organic compounds. After 30 days of aerobic incubation, 77.1 % of TFM transferred to high-molecular-weight compounds and bound residues, 7.8% CO{submore » 2}, and 2.2% remained unchanged. Reduced TFM reached a maximum level at Day 7 (38.4%), then decreased to 0.3% by Day 30. Incorporation could be caused by cross-coupling between amines or phenols independently, or between amines and phenols with subsequent bonding coupled compounds to sediment humic substances. Furthermore, polar compounds formed under aerobic conditions could be the products of substitution of the nitro group of TFM by a hydroxyl group, subsequent oxidation to quinone, polymerization, and bonding of polyphenols with sediment amino acids and peptides. These data suggest that TFM degrades under aerobic conditions to polar products, bound residues, and CO{sub 2}, and it degrades even faster tinder anaerobic conditions to reduced TFM, which seems to persist.« less

Tetrahydrocannabinols in clinical and forensic toxicology.

PubMed

Kochanowski, Maciej; Kała, Maria

2005-01-01

Cannabinoids are the natural constituents of marihuana (cannabis). The main of them are delta9-tetrahydrocannabinol (9THC)--psychoactive agent, cannabinol (CBN) and cannabidiol (CBD). Cannabis is administered either by smoking or orally. 9THC potency and duration of action as well as its and two of its major metabolites concentrations in organism highly depend on the route of administration. A single active dose of 9THC is estimated on 520 mg. 9THC is rapidly metabolised. It is hydroxylated to an active metabolite, I1 -hydroxy-delta9-tetrahydro-cannabinol (11-OH-THC), then oxidised to an inactive 11-nor-9-carboxy-delta9-tetrahydrocannabinol (THCCOOH), which is conjugated with glucuronic acid and predominantly excreted in the urine. The maximum psychological effect persists for 4-6 h after administration despite of very low 9THC blood concentrations. 9THC plasma concentration declined to values of 2-3 ng/ml during 3-4 h after smoking. Such a low concentration of the active compound in human organism create a demand for use of sensitive analytical methods for detection and determination of 9THC and its metabolites. The most effective techniques for 9THC and related compounds determination in biological material are chromatographic ones (gas and liquid) with mass spectrometric detection and different ionization modes. 9THC and its two metabolites (11-OH-THC and THCCOOH) are present in blood and hair, 9THC in saliva, and THCCOOH in urine. 9THC and related compounds are determined in autopsy material, although deaths by overdose of cannabis are exceptionally rare. Fatalities happen most often after intravenous injection of hashish oil. 9THC and its metabolites determination in different biological materials gives the basis for a wide interpretation of analytical results for clinical and forensic toxicology purposes.

In-stream attenuation of neuro-active pharmaceuticals and their metabolites

USGS Publications Warehouse

Writer, Jeffrey; Antweiler, Ronald C.; Ferrar, Imma; Ryan, Joseph N.; Thurman, Michael

2013-01-01

In-stream attenuation was determined for 14 neuro-active pharmaceuticals and associated metabolites. Lagrangian sampling, which follows a parcel of water as it moves downstream, was used to link hydrological and chemical transformation processes. Wastewater loading of neuro-active compounds varied considerably over a span of several hours, and thus a sampling regime was used to verify that the Lagrangian parcel was being sampled and a mechanism was developed to correct measured concentrations if it was not. In-stream attenuation over the 5.4-km evaluated reach could be modeled as pseudo-first-order decay for 11 of the 14 evaluated neuro-active pharmaceutical compounds, illustrating the capacity of streams to reduce conveyance of neuro-active compounds downstream. Fluoxetine and N-desmethyl citalopram were the most rapidly attenuated compounds (t1/2 = 3.6 ± 0.3 h, 4.0 ± 0.2 h, respectively). Lamotrigine, 10,11,-dihydro-10,11,-dihydroxy-carbamazepine, and carbamazepine were the most persistent (t1/2 = 12 ± 2.0 h, 12 ± 2.6 h, 21 ± 4.5 h, respectively). Parent compounds (e.g., buproprion, carbamazepine, lamotrigine) generally were more persistent relative to their metabolites. Several compounds (citalopram, venlafaxine, O-desmethyl-venlafaxine) were not attenuated. It was postulated that the primary mechanism of removal for these compounds was interaction with bed sediments and stream biofilms, based on measured concentrations in stream biofilms and a column experiment using stream sediments.

Geogenic organic contaminants in the low-rank coal-bearing Carrizo-Wilcox aquifer of East Texas, USA

USGS Publications Warehouse

Chakraborty, Jayeeta; Varonka, Matthew S.; Orem, William H.; Finkelman, Robert B.; Manton, William

2017-01-01

The organic composition of groundwater along the Carrizo-Wilcox aquifer in East Texas (USA), sampled from rural wells in May and September 2015, was examined as part of a larger study of the potential health and environmental effects of organic compounds derived from low-rank coals. The quality of water from the low-rank coal-bearing Carrizo-Wilcox aquifer is a potential environmental concern and no detailed studies of the organic compounds in this aquifer have been published. Organic compounds identified in the water samples included: aliphatics and their fatty acid derivatives, phenols, biphenyls, N-, O-, and S-containing heterocyclic compounds, polycyclic aromatic hydrocarbons (PAHs), aromatic amines, and phthalates. Many of the identified organic compounds (aliphatics, phenols, heterocyclic compounds, PAHs) are geogenic and originated from groundwater leaching of young and unmetamorphosed low-rank coals. Estimated concentrations of individual compounds ranged from about 3.9 to 0.01 μg/L. In many rural areas in East Texas, coal strata provide aquifers for drinking water wells. Organic compounds observed in groundwater are likely to be present in drinking water supplied from wells that penetrate the coal. Some of the organic compounds identified in the water samples are potentially toxic to humans, but at the estimated levels in these samples, the compounds are unlikely to cause acute health problems. The human health effects of low-level chronic exposure to coal-derived organic compounds in drinking water in East Texas are currently unknown, and continuing studies will evaluate possible toxicity.

Water-quality assessment of south-central Texas: Occurrence and distribution of volatile organic compounds in surface water and ground water, 1983-94, and implications for future monitoring

USGS Publications Warehouse

Ging, P.B.; Judd, L.J.; Wynn, K.H.

1997-01-01

The study area of the South-Central Texas study unit of the National Water-Quality Assessment Program comprises the Edwards aquifer in the San Antonio region and its catchment area. The first phase of the assessment includes evaluation of existing water-quality data for surface water and ground water, including volatile organic compounds, to determine the scope of planned monitoring. Most analyses of volatile organic compounds in surface water are from the National Pollutant Discharge Elimination System sites in San Antonio, Texas. Nine volatile organic compounds were detected at the six sites. The three compounds with the most detections at National Pollutant Discharge Elimination System sites are 1,2,4-trimethylbenzene, toluene, and xylene. Analysis of volatile organic compounds in ground water was limited to Edwards aquifer wells. Twenty-eight volatile organic compounds were detected in samples from 89 wells. The five most commonly detected compounds in samples from wells, in descending order, are tetrachloroethene, trichloroethene, bromoform, chloroform, and dibromochloromethane. Detections of volatile organic compounds in surface water and ground water within the South-Central Texas study area are limited to site-specific sources associated with development; therefore, planned monitoring for possible detections of volatile organic compounds as part of the National Water-Quality Assessment Program will emphasize areas of expanding population and development. Monitoring of volatile organic compounds is planned at National Pollutant Discharge Elimination System sites, at basic fixed surface-water sites, and in the ground-water study-unit surveys.

Selected ground-water data, Chester County, Pennsylvania

USGS Publications Warehouse

Sloto, Ronald A.

1989-01-01

Hydrologic data for Chester County, Pennsylvania are given for 3,010 wells and 32 springs. Water levels are given for 48 observation wells measured monthly during 1936-86. Chemical analyses of ground water are given for major ions, physical properties, nutrients, metals and other trace constituents, volatile organic compounds, acid organic compounds, base-neutral organic compounds, organochlorine insecticides, polychlorinated biphenyls, polychlorinated napthalenes, organophosphorous insecticides, organic acid herbicides, triazine herbicides, other organic compounds, and radionuclides.

User's guide for polyethylene-based passive diffusion bag samplers to obtain volatile organic compound concentrations in wells. Part I, Deployment, recovery, data interpretation, and quality control and assurance

USGS Publications Warehouse

Vroblesky, Don A.

2001-01-01

Diffusion samplers installed in observation wells were found to be capable of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags containing deionized water and relied on diffusion of chlorinated volatile organic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile organic compound concentrations in water samples obtained using the samplers without prior purging were similar to concentrations in water samples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.

User's guide for polyethylene-based passive diffusion bag samplers to obtain volatile organic compound concentrations in wells. Part 2, Field tests

USGS Publications Warehouse

Vroblesky, Don A.

2001-01-01

Diffusion samplers installed in observation wells were found to be capable of yielding representative water samples for chlorinated volatile organic compounds. The samplers consisted of polyethylene bags containing deionized water and relied on diffusion of chlorinated volatile organic compounds through the polyethylene membrane. The known ability of polyethylene to transmit other volatile compounds, such as benzene and toluene, indicates that the samplers can be used for a variety of volatile organic compounds. In wells at the study area, the volatile organic compound concentrations in water samples obtained using the samplers without prior purging were similar to concentrations in water samples obtained from the respective wells using traditional purging and sampling approaches. The low cost associated with this approach makes it a viable option for monitoring large observation-well networks for volatile organic compounds.

Organic Pollutants in Shale Gas Flowback and Produced Waters: Identification, Potential Ecological Impact, and Implications for Treatment Strategies.

PubMed

Butkovskyi, Andrii; Bruning, Harry; Kools, Stefan A E; Rijnaarts, Huub H M; Van Wezel, Annemarie P

2017-05-02

Organic contaminants in shale gas flowback and produced water (FPW) are traditionally expressed as total organic carbon (TOC) or chemical oxygen demand (COD), though these parameters do not provide information on the toxicity and environmental fate of individual components. This review addresses identification of individual organic contaminants in FPW, and stresses the gaps in the knowledge on FPW composition that exist so far. Furthermore, the risk quotient approach was applied to predict the toxicity of the quantified organic compounds for fresh water organisms in recipient surface waters. This resulted in an identification of a number of FPW related organic compounds that are potentially harmful namely those compounds originating from shale formations (e.g., polycyclic aromatic hydrocarbons, phthalates), fracturing fluids (e.g., quaternary ammonium biocides, 2-butoxyethanol) and downhole transformations of organic compounds (e.g., carbon disulfide, halogenated organic compounds). Removal of these compounds by FPW treatment processes is reviewed and potential and efficient abatement strategies are defined.

Organic Pollutants in Shale Gas Flowback and Produced Waters: Identification, Potential Ecological Impact, and Implications for Treatment Strategies

PubMed Central

2017-01-01

Organic contaminants in shale gas flowback and produced water (FPW) are traditionally expressed as total organic carbon (TOC) or chemical oxygen demand (COD), though these parameters do not provide information on the toxicity and environmental fate of individual components. This review addresses identification of individual organic contaminants in FPW, and stresses the gaps in the knowledge on FPW composition that exist so far. Furthermore, the risk quotient approach was applied to predict the toxicity of the quantified organic compounds for fresh water organisms in recipient surface waters. This resulted in an identification of a number of FPW related organic compounds that are potentially harmful namely those compounds originating from shale formations (e.g., polycyclic aromatic hydrocarbons, phthalates), fracturing fluids (e.g., quaternary ammonium biocides, 2-butoxyethanol) and downhole transformations of organic compounds (e.g., carbon disulfide, halogenated organic compounds). Removal of these compounds by FPW treatment processes is reviewed and potential and efficient abatement strategies are defined. PMID:28376616

Organic Analysis of Catalytic Fischer-Tropsch Type Synthesis Products: Are they Similar to Organics in Chondritic Meteorites?

NASA Technical Reports Server (NTRS)

Yazzie, Cyriah A.; Locke, Darren R.; Johnson, Natasha M.

2014-01-01

Fischer-Tropsch Type (FTT) synthesis of organic compounds has been hypothesized to occur in the early solar nebula that formed our Solar System. FTT is a collection of abiotic chemical reactions that convert a mixture of carbon monoxide and hydrogen over nano-catalysts into hydrocarbons and other more complex aromatic compounds. We hypothesized that FTT can generate similar organic compounds as those seen in chondritic meteorites; fragments of asteroids that are characteristic of the early solar system. Specific goals for this project included: 1) determining the effects of different FTT catalyst, reaction temperature, and cycles on organic compounds produced, 2) imaging of organic coatings found on the catalyst, and 3) comparison of organic compounds produced experimentally by FTT synthesis and those found in the ordinary chondrite LL5 Chelyabinsk meteorite. We used Pyrolysis Gas Chromatography Mass Spectrometry (PY-GCMS) to release organic compounds present in experimental FTT and meteorite samples, and Scanning Electron Microscopy (SEM) to take images of organic films on catalyst grains.

Non-hormonal male contraception: A review and development of an Eppin based contraceptive.

PubMed

O'Rand, Michael G; Silva, Erick J R; Hamil, Katherine G

2016-01-01

Developing a non-hormonal male contraceptive requires identifying and characterizing an appropriate target and demonstrating its essential role in reproduction. Here we review the development of male contraceptive targets and the current therapeutic agents under consideration. In addition, the development of EPPIN as a target for contraception is reviewed. EPPIN is a well characterized surface protein on human spermatozoa that has an essential function in primate reproduction. EPPIN is discussed as an example of target development, testing in non-human primates, and the search for small organic compounds that mimic contraceptive antibodies; binding EPPIN and blocking sperm motility. Although many hurdles remain before the success of a non-hormonal male contraceptive, continued persistence should yield a marketable product. Copyright © 2015 Elsevier Inc. All rights reserved.

Lattice dynamics and the nature of structural transitions in organolead halide perovskites

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

Comin, Riccardo; Crawford, Michael K.; Said, Ayman H.

Organolead halide perovskites are a family of hybrid organic-inorganic compounds whose remarkable optoelectronic properties have been under intensive scrutiny in recent years. Here we use inelastic x-ray scattering to study low-energy lattice excitations in single crystals of methylammonium lead iodide and bromide perovskites. Our findings confirm the displacive nature of the cubic-to-tetragonal phase transition, which is further shown, using neutron and x-ray diffraction, to be close to a tricritical point. Lastly, we detect quasistatic symmetry-breaking nanodomains persisting well into the high-temperature cubic phase, possibly stabilized by local defects. These findings reveal key structural properties of these materials, and also bearmore » important implications for carrier dynamics across an extended temperature range relevant for photovoltaic applications.« less

Enzyme activity in terrestrial soil in relation to exploration of the Martian surface

NASA Technical Reports Server (NTRS)

Ardakani, M. S.; Mclaren, A. D.; Pukite, A. H.

1972-01-01

An exploration was made of enzyme activities in soil, including abundance, persistence and localization of these activities. An attempt was made to develop procedures for the detection and assaying of enzymes in soils suitable for presumptive tests for life in planetary soils. A suitable extraction procedure for soil enzymes was developed and measurements were made of activities in extracts in order to study how urease is complexed in soil organic matter. Mathematical models were developed, based on enzyme action and microbial growth in soil, for rates of oxidation of nitrogen as nitrogen compounds are moved downward in soil by water flow. These biogeochemical models should be applicable to any percolating system, with suitable modification for special features, such as oxygen concetrations, and types of hydrodynamic flow.

Deriving persistence indicators from regulatory water-sediment studies – opportunities and limitations in OECD 308 data.

PubMed

Honti, Mark; Fenner, Kathrin

2015-05-19

The OECD guideline 308 describes a laboratory test method to assess aerobic and anaerobic transformation of organic chemicals in aquatic sediment systems and is an integral part of tiered testing strategies in different legislative frameworks for the environmental risk assessment of chemicals. The results from experiments carried out according to OECD 308 are generally used to derive persistence indicators for hazard assessment or half-lives for exposure assessment. We used Bayesian parameter estimation and system representations of various complexities to systematically assess opportunities and limitations for estimating these indicators from existing data generated according to OECD 308 for 23 pesticides and pharmaceuticals. We found that there is a disparity between the uncertainty and the conceptual robustness of persistence indicators. Disappearance half-lives are directly extractable with limited uncertainty, but they lump degradation and phase transfer information and are not robust against changes in system geometry. Transformation half-lives are less system-specific but require inverse modeling to extract, resulting in considerable uncertainty. Available data were thus insufficient to derive indicators that had both acceptable robustness and uncertainty, which further supports previously voiced concerns about the usability and efficiency of these costly experiments. Despite the limitations of existing data, we suggest the time until 50% of the parent compound has been transformed in the entire system (DegT(50,system)) could still be a useful indicator of persistence in the upper, partially aerobic sediment layer in the context of PBT assessment. This should, however, be accompanied by a mandatory reporting or full standardization of the geometry of the experimental system. We recommend transformation half-lives determined by inverse modeling to be used as input parameters into fate models for exposure assessment, if due consideration is given to their uncertainty.

Anthropogenic impacts on deep submarine canyons of the western Mediterranean Sea

NASA Astrophysics Data System (ADS)

Sanchez-Vidal, A.; Tubau, X.; Llorca, M.; Woodall, L.; Canals, M.; Farré, M.; Barceló, D.; Thompson, R.

2016-02-01

Submarine canyons are seafloor geomorphic features connecting the shallow coastal ocean to the deep continental margin and basin. Often considered biodiversity hotspots, submarine canyons have been identified as preferential pathways for water, sediment, pollutant and litter transfers from the coastal to the deep ocean. Here we provide insights on the presence of some of the most insidious man-made debris and substances in submarine canyons of the western Mediterranean Sea, which are relevant to achieve a "Good Environmental Status" by 2020 as outlined in the European Union's ambitious Marine Strategy Framework Directive. Ranked by size on a decreasing basis, we review the origin, distribution and transport mechanisms of i) marine litter, including plastic, lost fishing gear and metallic objects; ii) microplastics in the form of fibers of rayon, polyester, polyamide and acetates; and iii) persistent organic pollutants including the toxic and persistent perfluoroalkyl substances. This integrated analysis allows us to understand the pivotal role of atmospheric driven oceanographic processes occurring in Mediterranean deep canyons (dense shelf water cascading, coastal storms) in spreading any type of man-made compound to the deep sea, where they sink and accumulate before getting buried.

Contribution of fecal egestion to the whole body elimination of polychlorinated biphenyls by Japanese koi (Cyprinus carpio).

PubMed

Paterson, Gord; Liu, Jian; Haffner, G Douglas; Drouillard, Ken G

2010-08-01

This research investigated dose-dependent whole body and fecal elimination of 39 polychlorinated biphenyl (PCB) congeners spanning a range of chemical hydrophobicities (log Kow) by the Japanese koi (Cyprinus carpio). Both whole body (ktot) and fecal (keg) PCB congener elimination rate coefficients were negatively correlated with log Kow and observed to be dose independent. PCB congener ktot values determined for koi were representative of those generated for fish species of similar size and reared at near optimal temperatures. For persistent and metabolized-type PCB congeners, no significant difference was observed between the regressions describing the relationships between ktot and log Kow for these congeners. Individual PCB congener keg coefficient estimates ranged between 1% and 20% of their respective ktot values but averaged only 5% of the magnitude of ktot over a log Kow range of 5.7-7.8. These results verify first-order kinetics of PCB elimination by a fish species and demonstrate that the relative contribution of keg to ktot is negligible, even for highly hydrophobic (log Kow>6.5) compounds. It was concluded that gill elimination is the primary mechanism of elimination for persistent organic pollutants such as PCBs by Japanese koi.

Factors affecting the dissipation of pharmaceuticals in freshwater sediments.

PubMed

Al-Khazrajy, Omar S A; Bergström, Ed; Boxall, Alistair B A

2018-03-01

Degradation is one of the key processes governing the impact of pharmaceuticals in the aquatic environment. Most studies on the degradation of pharmaceuticals have focused on soil and sludge, with fewer exploring persistence in aquatic sediments. We investigated the dissipation of 6 pharmaceuticals from different therapeutic classes in a range of sediment types. Dissipation of each pharmaceutical was found to follow first-order exponential decay. Half-lives in the sediments ranged from 9.5 (atenolol) to 78.8 (amitriptyline) d. Under sterile conditions, the persistence of pharmaceuticals was considerably longer. Stepwise multiple linear regression analysis was performed to explore the relationships between half-lives of the pharmaceuticals, sediment physicochemical properties, and sorption coefficients for the compounds. Sediment clay, silt, and organic carbon content and microbial activity were the predominant factors related to the degradation rates of diltiazem, cimetidine, and ranitidine. Regression analysis failed to highlight a key property which may be responsible for observed differences in the degradation of the other pharmaceuticals. The present results suggest that the degradation rate of pharmaceuticals in sediments is determined by different factors and processes and does not exclusively depend on a single sediment parameter. Environ Toxicol Chem 2018;37:829-838. © 2017 SETAC. © 2017 SETAC.

Surface-water-quality assessment of the Yakima River basin, Washington; distribution of pesticides and other organic compounds in water, sediment, and aquatic biota, 1987-91; with a section on dissolved organic carbon in the Yakima River basin

USGS Publications Warehouse

Rinella, Joseph F.; McKenzie, Stuart W.; Crawford, J. Kent; Foreman, William T.; Fuhrer, Gregory J.; Morace, Jennifer L.; Aiken, George R.

1999-01-01

During 1987-91, chemical data were collected for pesticides and other organic compounds in surface water, streambed sediment, suspended sediment, agricultural soil, and aquatic biota to determine the occurrence, distribution, transport, and fate of organic compounds in the Yakima River basin in Washington. The report describes the chemical and physical properties of the compounds most frequently detected in the water column; organochlorine compounds including DDT, organophosphorus compounds, thiocarbamate and sulfite compounds, acetamide and triazine compounds, and chlorophenoxy-acetic acid and benzoic compounds. Concentrations are evaluated relative to chronic-toxicity water quality criteria and guidelines for the protection of human health and freshwater aquatic life.

Persistent inflammation, immunosuppression, and catabolism and the development of chronic critical illness after surgery.

PubMed

Efron, Philip A; Mohr, Alicia M; Bihorac, Azra; Horiguchi, Hiroyuki; Hollen, McKenzie K; Segal, Mark S; Baker, Henry V; Leeuwenburgh, Christiaan; Moldawer, Lyle L; Moore, Frederick A; Brakenridge, Scott C

2018-05-25

As early as the 1990s, chronic critical illness, a distinct syndrome of persistent high-acuity illness requiring management in the ICU, was reported under a variety of descriptive terms including the "neuropathy of critical illness," "myopathy of critical illness," "ICU-acquired weakness," and most recently "post-intensive care unit syndrome." The widespread implementation of targeted shock resuscitation, improved organ support modalities, and evidence-based protocolized ICU care has resulted in significantly decreased in-hospital mortality within surgical ICUs, specifically by reducing early multiple organ failure deaths. However, a new phenotype of multiple organ failure has now emerged with persistent but manageable organ dysfunction, high resource utilization, and discharge to prolonged care facilities. This new multiple organ failure phenotype is now clinically associated with the rapidly increasing incidence of chronic critical illness in critically ill surgery patients. Although the underlying pathophysiology driving chronic critical illness remains incompletely described, the persistent inflammation, immunosuppression, and catabolism syndrome has been proposed as a mechanistic framework in which to explain the increased incidence of chronic critical illness in surgical ICUs. The purpose of this review is to provide a historic perspective of the epidemiologic evolution of multiple organ failure into persistent inflammation, immunosuppression, and catabolism syndrome; describe the mechanism that drives and sustains chronic critical illness, and review the long-term outcomes of surgical patients who develop chronic critical illness. Copyright © 2018 Elsevier Inc. All rights reserved.

Manmade organic compounds in the surface waters of the United States: a review of current understanding

USGS Publications Warehouse

Smith, James A.; Witkowski, Patrick J.; Fusillo, Thomas V.

1987-01-01

This report reviews the occurrence and distribution of manmade organic compounds in the surface waters of the United States. On the basis of their aqueous solubilities, nonionic organic compounds partition themselves between water, dissolved organic matter, particulate organic matter, and the lipid reservoirs of aquatic organisms. Ionized organic compounds can be absorbed to sediments, thereby reducing their aqueous concentrations. Transformation processes of photolysis, hydrolysis, biodegradation, and volatilization can attenuate organic compounds, and attenuation rate commonly follow a first-order kinetic process. Eight groups of manmade organic compounds are discussed: 1. Polychlorinated biphenyls and organochlorine insecticides, 2. Carbamate and organophosphorus insecticides, 3. Herbicides, 4. Phenols, 5. Halogenated aliphatic and monocyclic aromatic hydrocarbons, 6. Phthalate esters, 7. Polychlorinated dibenzo-p-dioxins, and 8. Polycyclic aromatic hydrocarbons. For each compound group, data pertaining to use, production, and properties are presented and discussed. Processes that influence that the environmental fate of each group, as determined primarily through laboratory studies, are reviewed, and important fate processes are identified. Environmental concentrations of compounds from each group in water, biota, and sediment are given to demonstrate representative values for comparison to concentrations determined during ongoing research. Finally, where sufficient data exist, regional and temporal contamination trends in the United States are discussed.

Manmade organic compounds in the surface waters of the United States; a review of current understanding

USGS Publications Warehouse

Smith, James A.; Witkowski, P.J.; Fusillo, Thomas V.

1988-01-01

This report reviews the occurrence and distribution of manmade organic compounds in the surface waters of the United States. On the basis of their aqueous solubilities, nonionic organic compounds partition themselves among water, dissolved organic matter, particulate organic matter, and the lipid reservoirs of aquatic organisms. Ionized organic compounds can be adsorbed to sediments, thereby reducing their aqueous concentrations. Transformation processes of photolysis, hydrolysis, biodegradation, and volatilization can attenuate organic compounds, and attenuation rates commonly follow a first-order kinetic process. Eight groups of manmade organic compounds are discussed: 1. Polychlorinated biphenyls and organochlorine insecticides, 2. Carbamate and organophosphorus insecticides, 3. Herbicides, 4. Phenols, 5. Halogenated aliphatic and monocyclic aromatic hydrocarbons, 6. Phthalate esters, 7. Polychlorinated dibenzo-p-dioxins, and 8. Polycyclic aromatic hydrocarbons. For each compound group, data pertaining to use, production, and properties are presented and discussed. Processes that influence the environmental fate of each group, as determined primarily through laboratory studies, are reviewed, and important fate processes are identified. Environmental concentrations of compounds from each group in water, biota, and sediment are given to demonstrate representative values for comparison with concentrations determined during ongoing research. Finally, where data are sufficient, regional and temporal contamination trends in the United States are discussed.

Increase in volatilization of organic compounds using air sparging through addition in alcohol in a soil-water system.

PubMed

Chao, Huan-Ping; Hsieh, Lin-Han Chiang; Tran, Hai Nguyen

2018-02-15

This study developed a novel method to promote the remediation efficiency of air sparging. According to the enhanced-volatilization theory presented in this study, selected alcohols added to groundwater can highly enhance the volatilization amounts of organic compounds with high Henry's law constants. In this study, the target organic compounds consisted of n-hexane, n-heptane, benzene, toluene, 1,1,2-trichloroethane, and tetrachloroethene. n-pentanol, n-hexanol, and n-heptanol were used to examine the changes in the volatilization amounts of organic compounds in the given period. Two types of soils with high and low organic matter were applied to evaluate the transport of organic compounds in the soil-water system. The volatilization amounts of the organic compounds increased with increasing alcohol concentrations. The volatilization amounts of the test organic compounds exhibited a decreasing order: n-heptanol>n-hexanol>n-pentanol. When 10mg/L n-heptanol was added to the system, the maximum volatilization enhancement rate was 18-fold higher than that in distilled water. Samples of soil with high organic matter might reduce the volatilization amounts by a factor of 5-10. In the present study, the optimal removal efficiency for aromatic compounds was approximately 98%. Copyright © 2017 Elsevier B.V. All rights reserved.

Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

DOEpatents

Doherty, Joseph P.; Marek, James C.

1989-01-01

A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper (II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the orginal organic compounds, is subsequently blended with high level radioactive sludge and transferred to a virtrification facility for processing into borosilicate glass for long-term storage.

Handwashing and Ebola virus disease outbreaks: A randomized comparison of soap, hand sanitizer, and 0.05% chlorine solutions on the inactivation and removal of model organisms Phi6 and E. coli from hands and persistence in rinse water.

PubMed

Wolfe, Marlene K; Gallandat, Karin; Daniels, Kyle; Desmarais, Anne Marie; Scheinman, Pamela; Lantagne, Daniele

2017-01-01

To prevent Ebola transmission, frequent handwashing is recommended in Ebola Treatment Units and communities. However, little is known about which handwashing protocol is most efficacious. We evaluated six handwashing protocols (soap and water, alcohol-based hand sanitizer (ABHS), and 0.05% sodium dichloroisocyanurate, high-test hypochlorite, and stabilized and non-stabilized sodium hypochlorite solutions) for 1) efficacy of handwashing on the removal and inactivation of non-pathogenic model organisms and, 2) persistence of organisms in rinse water. Model organisms E. coli and bacteriophage Phi6 were used to evaluate handwashing with and without organic load added to simulate bodily fluids. Hands were inoculated with test organisms, washed, and rinsed using a glove juice method to retrieve remaining organisms. Impact was estimated by comparing the log reduction in organisms after handwashing to the log reduction without handwashing. Rinse water was collected to test for persistence of organisms. Handwashing resulted in a 1.94-3.01 log reduction in E. coli concentration without, and 2.18-3.34 with, soil load; and a 2.44-3.06 log reduction in Phi6 without, and 2.71-3.69 with, soil load. HTH performed most consistently well, with significantly greater log reductions than other handwashing protocols in three models. However, the magnitude of handwashing efficacy differences was small, suggesting protocols are similarly efficacious. Rinse water demonstrated a 0.28-4.77 log reduction in remaining E. coli without, and 0.21-4.49 with, soil load and a 1.26-2.02 log reduction in Phi6 without, and 1.30-2.20 with, soil load. Chlorine resulted in significantly less persistence of E. coli in both conditions and Phi6 without soil load in rinse water (p<0.001). Thus, chlorine-based methods may offer a benefit of reducing persistence in rinse water. We recommend responders use the most practical handwashing method to ensure hand hygiene in Ebola contexts, considering the potential benefit of chlorine-based methods in rinse water persistence.

Emissions of unintentional persistent organic pollutants from open burning of municipal solid waste from developing countries

EPA Science Inventory

Open burning of waste is the most significant source of polychlorinated dibenzo-para-dioxins and dibenzofurans (PCDD/PCDF) in many national inventories prepared pursuant to the Stockholm Convention on Persistent Organic Pollutants (POPs). This is particularly true for developing ...

Neurotoxicity of Legacy and Emerging Persistent Organic Chemicals: A Proteomic Approach to Understand Adverse Outcome Pathways

EPA Science Inventory

During the past century, a vast number of persistent organic chemicals (POCs) have been manufactured and used in industrial, agricultural, public health, consumer products and other applications. Widespread use of legacy POCs, including chlorinated, brominated and fluorinated com...

Characteristics of organic compounds in PM2.5 at urban and remote areas in Korea

NASA Astrophysics Data System (ADS)

Choi, A.; Lee, J.; Shin, H. J.; Lee, M.; Jin seok, H.; Lim, J.

2016-12-01

Organic aerosols contain thousands of organic compounds and contribute to 20%-90% of the total fine aerosol mass (Kanakidou et al., 2005). These organic aerosols originate from anthropogenic and natural (biogenic and geologic) sources and alter physical and chemical properties in the atmosphere depending on the atmospheric and meteorological conditions. About one hundred individual organic compounds in PM2.5 at Seoul (urban area) and Baengnyeong Island (remote area) were identified and quantified using gas chromatography/mass spectrometry (GC/MS) in order to understand the characteristics of organic compounds in PM2.5 at these areas. Further, major factors to determine their concentrations in the atmosphere were investigated. Organic compounds analyzed in this study were classified into six groups, n-alkanes, polycyclic aromatic hydrocarbons (PAHs), hopanes, fatty acids (FA), dicarboxylic acids (DCAs), and sugars. Daily variation of organic compounds concentrations at Seoul were not high, while, the concentrations of organic compounds at Baengnyeong Island showed high daily variation. This is might due to frequent change of source strength and/or SOA formation in this region. Through correlations of organic compounds with other air pollutants and factor analysis at both sites, it found that major factors (or source) for the determination of organic compounds concentrations at Seoul and Baengnyeong Island were different. The major sources at Seoul were anthropogenic sources such as vehicular emission and coal combustions, while, SOA formation and biomass burning were more attributed more to the organic compounds concentrations at Baengnyeong Island.References Kanakidou, M., Seinfeld, J.H., Pandis, S.N., Barnes, I., Dentener, F.J., Facchini, M.C., Van Dingenen, R., Ervens, B., Nenes, A., Nielsen, C.J., Swietlicki, E., Putaud, J.P., Balkanski, Y., Fuzzi, S., Horth, J., Moortgat, G.K., Winterhalter, R., Myhre, C.E.L., Tsigaridis, K., Vignati, E., Stephanou, E.G., Wilson, J., 2005. Organic aerosol and global climate modelling: a review. Atmos. Chem. Phys. 5, 1053e1123.

Occupational exposure associated with reproductive dysfunction.

PubMed

Kumar, Sunil

2004-01-01

Evidence suggestive of harmful effects of occupational exposure on the reproductive system and related outcomes has gradually accumulated in recent decades, and is further compounded by persistent environmental endocrine disruptive chemicals. These chemicals have been found to interfere with the function of the endocrine system, which is responsible for growth, sexual development and many other essential physiological functions. A number of occupations are being reported to be associated with reproductive dysfunction in males as well as in females. Generally, occupations involving the manufacture/or application of some of the persistent chemicals that are not easily degradable as well as bio-accumulative chemicals, occupations involving intensive exposure to heat and radiation, occupations involving the use of toxic solvents as well as toxic fumes are reported to be associated with reproductive dysfunction. Occupational exposure of males to various persistent chemicals have been reported to have male mediated adverse reproductive outcomes in the form of abortion, reduction in fertility etc. with inconclusive or limited evidence. Nevertheless, there is a need for more well designed studies in order to implicate any individual chemical having such effects as in most occupations workers are exposed to raw, intermediate and finished products and there are also several confounding factors associated with lifestyles responsible for reproductive dysfunction. There is an urgent need to look at indiscriminate use of persistent chemicals especially pesticides and persistent organic pollutants (POP's) as these chemicals enter the food chain also and could be potential for exposure during the critical period of development. It is also necessary to impart information, and to educate about the safe use of these chemicals, as a very sensitive reproduction issue is involved with exposure to these chemicals. Occupational exposures often are higher than environmental exposures, so that epidemiological studies should be conducted on these chemicals, on a priority basis, which are reported to have adverse effects on reproduction in the experimental system.

Persistent organic pollutants (POPs) in fish with different feeding habits inhabiting a shallow lake ecosystem.

PubMed

Barni, María F Silva; Ondarza, Paola M; Gonzalez, Mariana; Da Cuña, Rodrigo; Meijide, Fernando; Grosman, Fabián; Sanzano, Pablo; Lo Nostro, Fabiana L; Miglioranza, Karina S B

2016-04-15

The occurrence of persistent organic pollutants (POPs) in the environment can affect organisms inhabiting aquatic systems, in particular shallow lakes that are vulnerable to environmental stressors. This study aimed to assess POPs accumulation and changes at histological and physiological levels in tissues of three fish species with different trophic habits. Gills, brain, muscle, liver and gonads of Odontesthes bonariensis, Oligosarcus jenynsii and Cyphocharax voga were collected from the shallow lake La Peregrina, located in an agricultural area from Argentina. In addition, contaminant levels in surface water (SW), suspended particulate matter (SPM) and bottom sediments (BS) were assessed. Histological lesions were evaluated in fish tissues and levels of vitellogenin (VTG) were assessed in plasma of male fish in order to correlate these alterations with the presence of POPs in the environment. Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were determined by GC-ECD. Biotic and abiotic samples showed the same POPs distribution pattern: OCPs>PCBs>PBDEs. Although tissue distribution of OCPs was species-specific, muscle showed the lowest levels in all species. The most abundant contaminants were endosulfans, suggesting their widespread use in the area. O. bonariensis showed the highest endosulfans levels in liver (184.2-219ngg(-1)wet w), which was associated with the high SPM levels considering this species is a filter feeder. The occurrence of PCBs and PBDEs shows the ubiquity of these pollutants in the area. Histological lesions in gills and liver of O. bonariensis and O. jenynsii, might be related with the high levels of endosulfans in these organs. The detection of VTG in males warns about a possible exposure to estrogenic compounds in the environment. In conclusion, the simultaneous exposure of fish to multiple environmental pollutants leads to different alterations, so measures should be taken in order to prevent their occurrence and toxic effects. Copyright © 2016 Elsevier B.V. All rights reserved.

Mechanochemical synthesis of organic compounds and composites with their participation

NASA Astrophysics Data System (ADS)

Lyakhov, Nikolai Z.; Grigorieva, Tatiana F.; Barinova, Antonina P.; Vorsina, I. A.

2010-05-01

The results of experimental studies in the mechanochemical synthesis of organic compounds and composites with their participation published over the last 15 years are described systematically. The key reactions of organic compounds are considered: synthesis of the salts of organic acids, acylation, substitution, dehalogenation, esterification, hydrometallation and other reactions. Primary attention is devoted to systems and compounds that cannot be obtained by traditional chemistry methods.

78 FR 11618 - Approval and Promulgation of Implementation Plans Tennessee: Revisions to Volatile Organic...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-19

... Promulgation of Implementation Plans Tennessee: Revisions to Volatile Organic Compound Definition AGENCY..., SIP revision adds 17 compounds to the list of compounds excluded from the definition of ``Volatile Organic Compound''. EPA is approving this SIP revision because the State has demonstrated that it is...

PERSISTENT CONTAMINANTS: NEW PRIORITIES, NEW CONCERNS

EPA Science Inventory

The Stockholm Convention on persistent organic pollutants (POPs) was adopted in 2001 to protect human health and the environment from chemicals that are highly toxic, persistent, bioaccumulative, and undergo long range transport. These POPs include 9 pesticides, polychlorin...

Contribution of Organically Grown Crops to Human Health

PubMed Central

Johansson, Eva; Hussain, Abrar; Kuktaite, Ramune; Andersson, Staffan C.; Olsson, Marie E.

2014-01-01

An increasing interest in organic agriculture for food production is seen throughout the world and one key reason for this interest is the assumption that organic food consumption is beneficial to public health. The present paper focuses on the background of organic agriculture, important public health related compounds from crop food and variations in the amount of health related compounds in crops. In addition, influence of organic farming on health related compounds, on pesticide residues and heavy metals in crops, and relations between organic food and health biomarkers as well as in vitro studies are also the focus of the present paper. Nutritionally beneficial compounds of highest relevance for public health were micronutrients, especially Fe and Zn, and bioactive compounds such as carotenoids (including pro-vitamin A compounds), tocopherols (including vitamin E) and phenolic compounds. Extremely large variations in the contents of these compounds were seen, depending on genotype, climate, environment, farming conditions, harvest time, and part of the crop. Highest amounts seen were related to the choice of genotype and were also increased by genetic modification of the crop. Organic cultivation did not influence the content of most of the nutritional beneficial compounds, except the phenolic compounds that were increased with the amounts of pathogens. However, higher amounts of pesticide residues and in many cases also of heavy metals were seen in the conventionally produced crops compared to the organic ones. Animal studies as well as in vitro studies showed a clear indication of a beneficial effect of organic food/extracts as compared to conventional ones. Thus, consumption of organic food seems to be positive from a public health point of view, although the reasons are unclear, and synergistic effects between various constituents within the food are likely. PMID:24717360

Review: Micro-organic contaminants in groundwater in China

NASA Astrophysics Data System (ADS)

Dong, Weihong; Xie, Wei; Su, Xiaosi; Wen, Chuanlei; Cao, Zhipeng; Wan, Yuyu

2018-03-01

Micro-organic contaminants (MOs) in groundwater, which may have adverse effects on human health and ecosystems worldwide, are gaining increased attention in China. A great deal of research has been conducted to investigate their sources, occurrences and behavior in aquifers. This paper reviews the main sources, distribution, concentrations and behavior of a wide range of MOs in groundwater in China. These MOs include well-established persistent organic pollutants—polycyclic aromatic hydrocarbons (PAHs), hexachlorocyclohexanes (HCHs), polychlorinated biphenyls (PCBs), endocrine disrupting chemicals (poly brominated diphenyl ethers (PBDEs), phthalic acid esters (PAEs), bisphenol A (BPA)—and some contaminants of emerging concern such as pharmaceutical and personal care products (antibiotics, caffeine, shampoos) and perfluorinated compounds (PFCs). The results reveal that the main MOs in groundwater are PAHs, organochlorine pesticides (OCPs), PBDEs, PAEs, and antibiotics. Moreover, some PFCs such as perfluorobutane sulfonic acid (PFBS), perfluorobutanoic acid (PFBA) and perfluorooctanoic acid (PFOA) have only recently been observed in groundwater as emerging organic contaminants. Additionally, most MOs are distributed in populated and industrialized areas such as the southeast coast of China. Finally, industrial emissions, wastewater treatment plant effluents and agricultural wastewater are found to be dominant sources of MOs in groundwater. Based on the existing pollution levels, regulation and amelioration of MOs are warranted.

Organic-walled microfossils in 3.2-billion-year-old shallow-marine siliciclastic deposits.

PubMed

Javaux, Emmanuelle J; Marshall, Craig P; Bekker, Andrey

2010-02-18

Although the notion of an early origin and diversification of life on Earth during the Archaean eon has received increasing support in geochemical, sedimentological and palaeontological evidence, ambiguities and controversies persist regarding the biogenicity and syngeneity of the record older than Late Archaean. Non-biological processes are known to produce morphologies similar to some microfossils, and hydrothermal fluids have the potential to produce abiotic organic compounds with depleted carbon isotope values, making it difficult to establish unambiguous traces of life. Here we report the discovery of a population of large (up to about 300 mum in diameter) carbonaceous spheroidal microstructures in Mesoarchaean shales and siltstones of the Moodies Group, South Africa, the Earth's oldest siliciclastic alluvial to tidal-estuarine deposits. These microstructures are interpreted as organic-walled microfossils on the basis of petrographic and geochemical evidence for their endogenicity and syngeneity, their carbonaceous composition, cellular morphology and ultrastructure, occurrence in populations, taphonomic features of soft wall deformation, and the geological context plausible for life, as well as a lack of abiotic explanation falsifying a biological origin. These are the oldest and largest Archaean organic-walled spheroidal microfossils reported so far. Our observations suggest that relatively large microorganisms cohabited with earlier reported benthic microbial mats in the photic zone of marginal marine siliciclastic environments 3.2 billion years ago.

Significant accumulation of persistent organic pollutants and dysregulation in multiple DNA damage repair pathways in the electronic-waste-exposed populations.

PubMed

He, Xiaobo; Jing, Yaqing; Wang, Jianhai; Li, Keqiu; Yang, Qiaoyun; Zhao, Yuxia; Li, Ran; Ge, Jie; Qiu, Xinghua; Li, Guang

2015-02-01

Electronic waste (e-waste) has created a worldwide environmental and health problem, by generating a diverse group of hazardous compounds such as persistent organic pollutants (POPs). Our previous studies demonstrated that populations from e-waste exposed region have a significantly higher level of chromosomal aberrancy and incidence of DNA damage. In this study, we further demonstrated that various POPs persisted at a significantly higher concentration in the exposed group than those in the unexposed group. The level of reactive oxygen species and micronucleus rate were also significantly elevated in the exposed group. RNA sequencing analysis revealed 31 genes in DNA damage responses and repair pathways that were differentially expressed between the two groups (Log2 ratio >1 or <-1). Our data demonstrated that both females and males of the exposed group have activated a series of DNA damage response genes; however many important DNA repair pathways have been dysregulated. Expressions of NEIL1/3 and RPA3, which are critical in initiating base pair and nucleotide excision repairs respectively, have been downregulated in both females and males of the exposed group. In contrast, expression of RNF8, an E3 ligase involved in an error prone non-homologous end joining repair for DNA double strand break, was upregulated in both genders of the exposed group. The other genes appeared to be differentially expressed only when the males or females of the two groups were compared respectively. Importantly, the expression of cell cycle regulatory gene CDC25A that has been implicated in multiple kinds of malignant transformation was significantly upregulated among the exposed males while downregulated among the exposed females. In conclusion, our studies have demonstrated significant correlations between e-waste disposing and POPs accumulation, DNA lesions and dysregulation of multiple DNA damage repair mechanisms in the residents of the e-waste exposed region. Copyright © 2014 Elsevier Inc. All rights reserved.

40 CFR 59.505 - How do I demonstrate compliance with the reactivity limits?

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND... Volatile Organic Compounds (VOC) in Consumer Products and Reactive Organic Compounds in Aerosol Coating...

Surface microlayer enrichment of volatile organic compounds and semi-volatile organic compounds in drinking water source.

PubMed

Huang, Zhi; Zhou, Wen; Yu, Ya-juan; Zhang, Ai-qian; Han, Shuo-kui; Wang, Lian-sheng

2004-01-01

Enrichment of volatile organic compounds(VOC) and semi-volatility organic compounds(SVOC) in surface microlayer(SM) of three drinking water sources were studied. The enrichment factor(EFs) were 0.67 to 13.37 and 0.16 to 136, respectively. The results showed some VOC and most SVOC could enrich in SM. Some EFs of SVOC was quite high. Suspension and temperature could affect EFs of SVOC, slim wind and water movement do not destroy enrichment of organic in SM.

STUDY DESIGN FOR A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC PESTICIDES "CTEPP"

EPA Science Inventory

The Children's Total Exposure to Persistent Pesticides and Other Persistent Pollutant (CTEPP) study is one of the largest aggregate exposure studies of young children in the United States. The CTEPP study examines the exposures of about 260 preschool children and their primary ad...

CTEPP STANDARD OPERATING PROCEDURE FOR EXTRACTING AND PREPARING AIR SAMPLES FOR ANALYSIS OF POLAR PERSISTENT ORGANIC POLLUTANTS (SOP-5.13)

EPA Science Inventory

The method for extracting and preparing indoor and outdoor air samples for analysis of polar persistent organic pollutants is summarized in this SOP. It covers the preparation of samples that are to be analyzed by gas chromatography/mass spectrometry.

CTEPP-OH DATA ANALYTICAL RESULTS ORGANIZED BY CHEMICAL AND MEDIA

EPA Science Inventory

This data set contains the field sample data by chemical and matrix for CTEPP-OH. The data is organized at the sample, chemical level.

The Children’s Total Exposure to Persistent Pesticides and Other Persistent Pollutant (CTEPP) study was one of the largest aggregate exposure ...

Multiplex screening of persistent organic pollutants in fish using spectrally encoded microspheres

USDA-ARS?s Scientific Manuscript database

Persistent organic pollutants (POPs) are food contaminants of global public health concern and known to be carcinogenic and endocrine disruptors. Their monitoring is essential and an easy-to-use, rapid and affordable multi-analyte screening method with simplified sample preparation can be a valuable...

CTEPP NC DATA ANALYTICAL RESULTS ORGANIZED BY CHEMICAL AND MEDIA

EPA Science Inventory

This data set contains the field sample data by chemical and matrix. The data are organized at the sample, chemical level.

The Children’s Total Exposure to Persistent Pesticides and Other Persistent Pollutant (CTEPP) study was one of the largest aggregate exposure studies of y...

Organic Compounds in Carbonaceous Meteorites

NASA Technical Reports Server (NTRS)

Cooper, Grorge

2001-01-01

Carbonaceous meteorites are relatively enriched in soluble organic compounds. To date, these compounds provide the only record available to study a range of organic chemical processes in the early Solar System chemistry. The Murchison meteorite is the best-characterized carbonaceous meteorite with respect to organic chemistry. The study of its organic compounds has related principally to aqueous meteorite parent body chemistry and compounds of potential importance for the origin of life. Among the classes of organic compounds found in Murchison are amino acids, amides, carboxylic acids, hydroxy acids, sulfonic acids, phosphonic acids, purines and pyrimidines (Table 1). Compounds such as these were quite likely delivered to the early Earth in asteroids and comets. Until now, polyhydroxylated compounds (polyols), including sugars (polyhydroxy aldehydes or ketones), sugar alcohols, sugar acids, etc., had not been identified in Murchison. Ribose and deoxyribose, five-carbon sugars, are central to the role of contemporary nucleic acids, DNA and RNA. Glycerol, a three-carbon sugar alcohol, is a constituent of all known biological membranes. Due to the relative lability of sugars, some researchers have questioned the lifetime of sugars under the presumed conditions on the early Earth and postulated other (more stable) compounds as constituents of the first replicating molecules. The identification of potential sources and/or formation mechanisms of pre-biotic polyols would add to the understanding of what organic compounds were available, and for what length of time, on the ancient Earth.

Soil Organic Chemistry.

ERIC Educational Resources Information Center

Anderson, G.

1979-01-01

A brief review is presented of some of the organic compounds and reactions that occur in soil. Included are nitrogenous compounds, compounds of phosphorus and sulfur, carbohydrates, phenolic compounds, and aliphatic acids. (BB)

40 CFR 60.441 - Definitions and symbols.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... Fugitive volatile organic compounds means any volatile organic compounds which are emitted from the coating... capture fugitive volatile organic compounds. Oven means a chamber which uses heat or irradiation to bake... or label product. Solvent applied in the coating means all organic solvent contained in the adhesive...

40 CFR 60.441 - Definitions and symbols.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... Fugitive volatile organic compounds means any volatile organic compounds which are emitted from the coating... capture fugitive volatile organic compounds. Oven means a chamber which uses heat or irradiation to bake... or label product. Solvent applied in the coating means all organic solvent contained in the adhesive...

40 CFR 60.441 - Definitions and symbols.

Code of Federal Regulations, 2012 CFR

2012-07-01

.... Fugitive volatile organic compounds means any volatile organic compounds which are emitted from the coating... capture fugitive volatile organic compounds. Oven means a chamber which uses heat or irradiation to bake... or label product. Solvent applied in the coating means all organic solvent contained in the adhesive...

40 CFR 60.441 - Definitions and symbols.

Code of Federal Regulations, 2014 CFR

2014-07-01

... = the weight fraction of organics applied of each coating (i) applied during a calendar month as.... Fugitive volatile organic compounds means any volatile organic compounds which are emitted from the coating... capture fugitive volatile organic compounds. Oven means a chamber which uses heat or irradiation to bake...

GROUNDWATER TRANSPORT OF HYDROPHOBIC ORGANIC COMPOUNDS IN THE PRESENCE OF DISSOLVED ORGANIC MATTER

EPA Science Inventory

The effects of dissolved organic matter (DOM) on the transport of hydrophobic organic compounds in soil columns were investigated. Three compounds (naphthalene, phenanthrene and DDT) that spanned three orders of magnitude in water solubility were used. Instead of humic matter, mo...

Soil amino compound and carbohydrate contents influenced by organic amendments

USDA-ARS?s Scientific Manuscript database

Amino compounds (i. e. amino acids and sugars), and carbohydrates are labile organic components and contribute to the improvement of soil fertility and quality. Animal manure and other organic soil amendments are rich in both amino compounds and carbohydrates, hence organic soil amendments might af...

Automated gas chromatography

DOEpatents

Mowry, C.D.; Blair, D.S.; Rodacy, P.J.; Reber, S.D.

1999-07-13

An apparatus and process for the continuous, near real-time monitoring of low-level concentrations of organic compounds in a liquid, and, more particularly, a water stream. A small liquid volume of flow from a liquid process stream containing organic compounds is diverted by an automated process to a heated vaporization capillary where the liquid volume is vaporized to a gas that flows to an automated gas chromatograph separation column to chromatographically separate the organic compounds. Organic compounds are detected and the information transmitted to a control system for use in process control. Concentrations of organic compounds less than one part per million are detected in less than one minute. 7 figs.

Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

DOEpatents

Doherty, J.P.; Marek, J.C.

1987-02-25

A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper(II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the original organic compounds, is subsequently blended with high level radioactive sludge land transferred to a vitrification facility for processing into borosilicate glass for long-term storage. 2 figs., 3 tabs.

Oceanic protection of prebiotic organic compounds from UV radiation

NASA Technical Reports Server (NTRS)

Cleaves, H. J.; Miller, S. L.; Bada, J. L. (Principal Investigator)

1998-01-01

It is frequently stated that UV light would cause massive destruction of prebiotic organic compounds because of the absence of an ozone layer. The elevated UV flux of the early sun compounds this problem. This applies to organic compounds of both terrestrial and extraterrestrial origin. Attempts to deal with this problem generally involve atmospheric absorbers. We show here that prebiotic organic polymers as well as several inorganic compounds are sufficient to protect oceanic organic molecules from UV degradation. This aqueous protection is in addition to any atmospheric UV absorbers and should be a ubiquitous planetary phenomenon serving to increase the size of planetary habitable zones.

Automated gas chromatography

DOEpatents

Mowry, Curtis D.; Blair, Dianna S.; Rodacy, Philip J.; Reber, Stephen D.

1999-01-01

An apparatus and process for the continuous, near real-time monitoring of low-level concentrations of organic compounds in a liquid, and, more particularly, a water stream. A small liquid volume of flow from a liquid process stream containing organic compounds is diverted by an automated process to a heated vaporization capillary where the liquid volume is vaporized to a gas that flows to an automated gas chromatograph separation column to chromatographically separate the organic compounds. Organic compounds are detected and the information transmitted to a control system for use in process control. Concentrations of organic compounds less than one part per million are detected in less than one minute.

Water-quality assessment of the Ozark Plateaus study unit, Arkansas, Kansas, Missouri, and Oklahoma; organic compounds in surface water, bed sediment, and biological tissue, 1992-95

USGS Publications Warehouse

Bell, Richard W.; Davis, Jerri V.; Femmer, Suzanne R.; Joseph, Robert L.

1997-01-01

Organic-compound samples, including pesticides and semi-volatiles, were collected from 1992-95 at 43 surface-water and 27 bed-sediment and biological-tissue sampling sites within the Ozark Plateaus National Water-Quality Assessment Program study unit. Most surface-water, bed-sediment, and biological-tissue sites have drainage basins predominantly in the Springfield and Salem Plateaus. At most surface-water sampling sites, one to three pesticide samples were collected in the spring and early summer of 1994 and 1995; two sites had additional samples collected either weekly, biweekly, or monthly from February 1994 through December 1994. At most bed-sediment and biological-tissue sampling sites, a single organic-compounds sample was collected. Agricultural pesticide use was approximately 4.9 million pounds of active ingredients per year from 1987-91 in the study unit and was generally greatest in the Springfield and Salem Plateaus pasturelands and in the Osage Plains and Mississippi Alluvial Plain cropland areas. The most frequently applied pesticide in the study unit was 2,4-D. Atrazine was the second most frequently applied pesticide. Corn, pasture, rice, sorghum, and soybeans received approximately 85 percent of the pesticides applied within the study unit. The highest pesticide application rate occurred on these crops in the Mississippi Alluvial and Osage Plains. Pastureland was the crop type that received the greatest amount of pesticides in 53 of the 96 counties in the study unit. The most commonly detected herbicide (63 samples) in surface water was atrazine. Five other pesticides--desethylatrazine, tebuthiuron, prometon, metolachlor, and simazine--were detected in 15 or more samples. The most commonly detected insecticide (13 samples) was p,p'-DDE. Two other insecticides, diazinon and cis-permethrin, were detected in seven or more samples. Pesticides were detected at 39 surface-water sites; samples collected at Yocum Creek near Oak Grove, Ark. had the most pesticide detections (13). Seventeen other sites had samples with six or more pesticide detections. Analysis of pesticide data collected at surface-water sites indicates that the largest variety of different pesticides detected (18) was in small, agricultural drainage basins; the largest percentage of detections of a single pesticide (about 80) was in medium, agricultural basins. Pesticide concentrations were small, and in most cases, at or near the detection limit. Maximum concentrations ranged from 0.001 to 0.007 micrograms per liter (mg/L) at small, forest sites; 0.001 to 0.029 mg/L at medium, forest sites; 0.001 to 0.079 mg/L at small, agricultural sites; and 0.003 to 0.29 mg/L at medium, agricultural sites. Pesticides were detected significantly more often in medium, agricultural basins in the Springfield Plateau. The most commonly detected (13 samples) organic compound in bed sediment, in concentrations noticeably above background levels, was 2,6-dimethylnaphthalene; the maximum concentration of 2,6-dimethylnaphthalene was 130 micrograms per kilogram. Seventeen or more compounds were detected in bed-sediment samples collected at three sites. Four compounds were detected in biological-tissue samples: p,p'-DDT in Corbicula fluminea (Asiatic clam) tissue collected at the Osage River near St. Thomas, Mo. and cis-chlordane, trans-chlordane, and trans-nonachlor in C. fluminea tissue collected at the James River near Boaz, Mo. Organic compounds collected at surface-water, bed-sediment, or biological-tissue sampling sites were not detected in concentrations that exceeded any health criteria or standards. Based on this information, organic compounds do not pose any widespread or persistent problems in the study unit.

Antibacterial Activity of 1-[(2,4-Dichlorophenethyl)amino]-3-Phenoxypropan-2-ol against Antibiotic-Resistant Strains of Diverse Bacterial Pathogens, Biofilms and in Pre-clinical Infection Models.

PubMed

Defraine, Valerie; Verstraete, Laure; Van Bambeke, Françoise; Anantharajah, Ahalieyah; Townsend, Eleanor M; Ramage, Gordon; Corbau, Romu; Marchand, Arnaud; Chaltin, Patrick; Fauvart, Maarten; Michiels, Jan

2017-01-01

We recently described the novel anti-persister compound 1-[(2,4-dichlorophenethyl)amino]-3-phenoxypropan-2-ol (SPI009), capable of directly killing persister cells of the Gram-negative pathogen Pseudomonas aeruginosa . This compound also shows antibacterial effects against non-persister cells, suggesting that SPI009 could be used as an adjuvant for antibacterial combination therapy. Here, we demonstrate the broad-spectrum activity of SPI009, combined with different classes of antibiotics, against the clinically relevant ESKAPE pathogens Enterobacter aerogenes, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, P. aeruginosa, Enterococcus faecium and Burkholderia cenocepacia and Escherichia coli . Importantly, SPI009 re-enabled killing of antibiotic-resistant strains and effectively lowered the required antibiotic concentrations. The clinical potential was further confirmed in biofilm models of P. aeruginosa and S. aureus where SPI009 exhibited effective biofilm inhibition and eradication. Caenorhabditis elegans infected with P. aeruginosa also showed a significant improvement in survival when SPI009 was added to conventional antibiotic treatment. Overall, we demonstrate that SPI009, initially discovered as an anti-persister molecule in P. aeruginosa , possesses broad-spectrum activity and is highly suitable for the development of antibacterial combination therapies in the fight against chronic infections.

Antibacterial Activity of 1-[(2,4-Dichlorophenethyl)amino]-3-Phenoxypropan-2-ol against Antibiotic-Resistant Strains of Diverse Bacterial Pathogens, Biofilms and in Pre-clinical Infection Models

PubMed Central

Defraine, Valerie; Verstraete, Laure; Van Bambeke, Françoise; Anantharajah, Ahalieyah; Townsend, Eleanor M.; Ramage, Gordon; Corbau, Romu; Marchand, Arnaud; Chaltin, Patrick; Fauvart, Maarten; Michiels, Jan

2017-01-01

We recently described the novel anti-persister compound 1-[(2,4-dichlorophenethyl)amino]-3-phenoxypropan-2-ol (SPI009), capable of directly killing persister cells of the Gram-negative pathogen Pseudomonas aeruginosa. This compound also shows antibacterial effects against non-persister cells, suggesting that SPI009 could be used as an adjuvant for antibacterial combination therapy. Here, we demonstrate the broad-spectrum activity of SPI009, combined with different classes of antibiotics, against the clinically relevant ESKAPE pathogens Enterobacter aerogenes, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, P. aeruginosa, Enterococcus faecium and Burkholderia cenocepacia and Escherichia coli. Importantly, SPI009 re-enabled killing of antibiotic-resistant strains and effectively lowered the required antibiotic concentrations. The clinical potential was further confirmed in biofilm models of P. aeruginosa and S. aureus where SPI009 exhibited effective biofilm inhibition and eradication. Caenorhabditis elegans infected with P. aeruginosa also showed a significant improvement in survival when SPI009 was added to conventional antibiotic treatment. Overall, we demonstrate that SPI009, initially discovered as an anti-persister molecule in P. aeruginosa, possesses broad-spectrum activity and is highly suitable for the development of antibacterial combination therapies in the fight against chronic infections. PMID:29312259

Palladium catalyzed hydrogenation of bio-oils and organic compounds

DOEpatents

Elliott, Douglas C [Kennewick, WA; Hu, Jianli [Richland, WA; Hart,; Todd, R [Kennewick, WA; Neuenschwander, Gary G [Burbank, WA

2011-06-07

The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

Palladium catalyzed hydrogenation of bio-oils and organic compounds

DOEpatents

Elliott, Douglas C [Richland, WA; Hu, Jianli [Kennewick, WA; Hart, Todd R [Kennewick, WA; Neuenschwander, Gary G [Burbank, WA

2008-09-16

The invention provides palladium-catalyzed hydrogenations of bio-oils and certain organic compounds. Experimental results have shown unexpected and superior results for palladium-catalyzed hydrogenations of organic compounds typically found in bio-oils.

Organic compounds in radiation fogs in Davis (California)

NASA Astrophysics Data System (ADS)

Herckes, Pierre; Hannigan, Michael P.; Trenary, Laurie; Lee, Taehyoung; Collett, Jeffrey L.

New stainless steel active fogwater collectors were designed and used in Davis (CA, USA) to collect fogwater for the speciation of organic matter. Organic compounds in fog samples were extracted by liquid-liquid extraction and analyzed by gas chromatography coupled to mass spectrometry. Numerous organic compounds, including various alkanes, polycyclic aromatic hydrocarbons (PAH) and alkanoic acids, have been identified in the fogwater samples. Higher molecular weight (MW) compounds are preferentially associated with an insoluble phase inside the fog drops, whereas lower molecular weight and more polar compounds are found predominantly in the dissolved phase. Concentrations in the dissolved phase were sometimes much higher than estimated by the compounds' aqueous solubilities.

Activation of α7 nicotinic acetylcholine receptors persistently enhances hippocampal synaptic transmission and prevents Aß-mediated inhibition of LTP in the rat hippocampus.

PubMed

Ondrejcak, Tomas; Wang, Qinwen; Kew, James N C; Virley, David J; Upton, Neil; Anwyl, Roger; Rowan, Michael J

2012-02-29

Nicotinic acetylcholine receptors mediate fast cholinergic modulation of glutamatergic transmission and synaptic plasticity. Here we investigated the effects of subtype selective activation of the α7 nicotinic acetylcholine receptors on hippocampal transmission and the inhibition of synaptic long-term potentiation by the Alzheimer's disease associated amyloid ß-protein (Aß). The α7 nicotinic acetylcholine receptor agonist "compound A" ((R)-N-(1-azabicyclo[2.2.2]oct-3-yl)(5-(2-pyridyl))thiophene-2-carboxamide) induced a rapid-onset persistent enhancement of synaptic transmission in the dentate gyrus in vitro. Consistent with a requirement for activation of α7 nicotinic acetylcholine receptors, the type II α7-selective positive allosteric modulator PheTQS ((3aR, 4S, 9bS)-4-(4-methylphenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c]quinoline-8-sulfonamide) potentiated, and the antagonist methyllycaconitine (MLA) prevented the persistent enhancement. Systemic injection of the agonist also induced a similar MLA-sensitive persistent enhancement of synaptic transmission in the CA1 area in vivo. Remarkably, although compound A did not affect control long-term potentiation (LTP) in vitro, it prevented the inhibition of LTP by Aß1-42 and this effect was inhibited by MLA. These findings strongly indicate that activation of α7 nicotinic acetylcholine receptors is sufficient to persistently enhance hippocampal synaptic transmission and to overcome the inhibition of LTP by Aß. Copyright © 2011 Elsevier B.V. All rights reserved.

Dietary Exposure of Fathead Minnows to the Explosives TNT and RDX and to the Pesticide DDT using Contaminated Invertebrates

PubMed Central

Houston, Jerre G.; Lotufo, Guilherme R.

2005-01-01

Explosive compounds have been released into the environment during manufacturing, handling, and usage procedures. These compounds have been found to persist in the environment and potentially promote detrimental biological effects. The lack of research on bioaccumulation and bioconcentration and especially dietary transfer on aquatic life has resulted in challenges in assessing ecological risks. The objective of this study was to investigate the potential trophic transfer of the explosive compounds 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) using a realistic freshwater prey/predator model and using dichlorodiphenyltrichloroethane (DDT), a highly bioaccumulative compound, to establish relative dietary uptake potential. The oligochaete worm Lumbriculus variegatus was exposed to 14C-labeled TNT, RDX or DDT for 5 hours in water, frozen in meal-size packages and subsequently fed to individual juvenile fathead minnows (Pimephales promelas). Fish were sampled for body residue determination on days 1, 2, 3, 4, 7, and 14 following an 8-hour gut purging period. Extensive metabolism of the parent compound in worms occurred for TNT but not for RDX and DDT. Fish body residue remained relatively unchanged over time for TNT and RDX, but did not approach steady-state concentration for DDT during the exposure period. The bioaccumulation factor (concentration in fish relative to concentration in worms) was 0.018, 0.010, and 0.422 g/g for TNT, RDX and DDT, respectively, confirming the expected relatively low bioaccumulative potential for TNT and RDX through the dietary route. The experimental design was deemed successful in determining the potential for trophic transfer of organic contaminants via a realistic predator/prey exposure scenario. PMID:16705829

Biocides in hydraulic fracturing: A comparison to agricultural and assessment of hazard and vulnerability with respect to groundwater pollution

NASA Astrophysics Data System (ADS)

Worrall, Fred; Wilson, Miles; Davies, Richard

2017-04-01

Biocides are one possible chemical additive to frack fluids and their role is to control bacterial growth. Since biocides are designed to be toxic to particular organisms, their accidental or deliberate release into the environment has become a growing topic of concern, especially with regards to fracking. The objective of this study was to consider whether biocides proposed for use in fracking, could be a threat to English groundwater based on past groundwater monitoring data. The study considered all groundwater samples analysed for biocides in English groundwater between 2005 and 2014. The monitoring records were compared to: records of application (both amount and area); and chemical and molecular data for the biocides. The study did not use traditional adsorption and degradation data as these parameters are prone to variability and are not pure molecular parameters. The study showed that of the 110 biocides tested for in English groundwaters in the decade 2005 - 2014. The total number of detections was 2234 out of 1475000 observations of 95 compounds, and 38 were compounds that were not applied during the period of record. The detection of these 38 compounds did not decline over the 10 year period implying very long residence times and that once compounds do pollute an aquifer, then they will be a persistent problem. The study was able to develop binomial regression models of the probability of detecting pesticide in groundwater based upon molecular and application variables; and solely upon molecular properties. The solubility of the range of biocides used in frack fluids would imply a potentially higher hazard than for most agricultural biocides, but molecular modelling implied that one compound could be safer than others.

Influence of treatment conditions on the oxidation of micropollutants by Trametes versicolor laccase.

PubMed

Margot, Jonas; Maillard, Julien; Rossi, Luca; Barry, D A; Holliger, Christof

2013-09-25

Many organic compounds present at low concentrations in municipal wastewater, such as various pharmaceuticals and biocides, are recalcitrant in conventional wastewater treatment plants (WWTPs). To improve their biodegradation, oxidoreductase enzymes such as laccases were tested. The goal was to find optimal conditions for the transformation of two anti-inflammatory pharmaceuticals (diclofenac (DFC) and mefenamic acid (MFA)), one biocide (triclosan (TCN)) and one plastic additive (bisphenol A (BPA)) by Trametes versicolor laccase. Experiments were conducted in spiked solutions at different pH values (from 3 to 9), enzyme concentrations (70-1400 Ul(-1)), reaction times (0-26 hours) and temperatures (10, 25 and 40°C) following a Doehlert experimental design. A semi-empirical model was developed to understand better the combined effects of the four factors and to determine optimal values. This model was able to fit well the experimental data (R(2)>0.97) and showed good predictive ability. All four factors had a significant effect on the micropollutant oxidation with the greatest influence shown by pH. Results for single compounds were different from those obtained for mixtures of micropollutants. For instance, DFC transformation occurred at much higher rates in mixtures under alkaline conditions. Optimal conditions were compound-dependent, but were found to be between pH 4.5 to 6.5 and between 25°C to more than 40°C. A laccase concentration of 730 Ul(-1) was sufficient to obtain a high removal rate (>90%) of the four individual compounds (range of times: 40 min to 5 hours), showing the potential of laccases to improve biodegradation of environmentally persistent compounds. Copyright © 2013 Elsevier B.V. All rights reserved.

77 FR 52606 - Approval and Promulgation of Air Quality Implementation Plans; Indiana; Volatile Organic...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-30

... Promulgation of Air Quality Implementation Plans; Indiana; Volatile Organic Compounds; Architectural and... sets limits on the amount of volatile organic compounds (VOC) in architectural and industrial... Indiana SIP a new rule within Title 326, Article 8 ``Volatile Organic Compound Rules'' that limits the VOC...

Oxidative degradation of nalidixic acid by nano-magnetite via Fe2+/O2-mediated reactions.

PubMed

Ardo, Sandy G; Nélieu, Sylvie; Ona-Nguema, Georges; Delarue, Ghislaine; Brest, Jessica; Pironin, Elsa; Morin, Guillaume

2015-04-07

Organic pollution has become a critical issue worldwide due to the increasing input and persistence of organic compounds in the environment. Iron minerals are potentially able to degrade efficiently organic pollutants sorbed to their surfaces via oxidative or reductive transformation processes. Here, we explored the oxidative capacity of nano-magnetite (Fe3O4) having ∼ 12 nm particle size, to promote heterogeneous Fenton-like reactions for the removal of nalidixic acid (NAL), a recalcitrant quinolone antibacterial agent. Results show that NAL was adsorbed at the surface of magnetite and was efficiently degraded under oxic conditions. Nearly 60% of this organic contaminant was eliminated after 30 min exposure to air bubbling in solution in the presence of an excess of nano-magnetite. X-ray diffraction (XRD) and Fe K-edge X-ray absorption spectroscopy (XANES and EXAFS) showed a partial oxidation of magnetite to maghemite during the reaction, and four byproducts of NAL were identified by liquid chromatography-mass spectroscopy (UHPLC-MS/MS). We also provide evidence that hydroxyl radicals (HO(•)) were involved in the oxidative degradation of NAL, as indicated by the quenching of the degradation reaction in the presence of ethanol. This study points out the promising potentialities of mixed valence iron oxides for the treatment of soils and wastewater contaminated by organic pollutants.

A Review on Polychlorinated Biphenyls (PCBs) and Polybrominated Diphenyl Ethers (PBDEs) in South Asia with a Focus on Malaysia.

PubMed

Kaw, Han Yeong; Kannan, Narayanan

Malaysia is a developing country in Southeast Asia, with rapid industrial and economic growth. Speedy population growth and aggressive consumerism in the past five decades have resulted in environmental pollution issues, including products containing polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). PCBs and PBDEs are classified as persistent organic pollutants (POPs) by the Stockholm Convention due to their persistence, bioaccumulation in the environment and toxicity to humans and wildlife. These compounds are known to cause liver dysfunction, thyroid toxicity, developmental neuro-toxicity and possibly cancer. PCBs in air, mussels, pellets, seawater, fresh water, and human breast milk samples were analyzed in Malaysia, while studies on the pollution level of PBDEs in Malaysia were conducted on mussels, soils, leachate and sediment samples. PCBs in breast milk collected from Malaysia was the highest among Asian developing countries, with mean concentration of 80 ng/g lipid weight. On the other hand, the mean concentration of PCBs in mussels collected from Malaysia recorded the second lowest, with 56 ng/g and 89 ng/g lipid weight in two studies respectively. The concentrations of PBDEs in mussels taken from Malaysia fall in the range of 0.84-16 ng/g lipid weight, which is considerably low compared to 104.5 ng/g lipid weight in Philippines and 90.59 ng/g in Korea. Nevertheless, there are limited studies on these compounds in Malaysia, particularly there is no research on PBDEs in breast milk and sediment samples. This review will summarize the contamination levels of PCBs and PBDEs in different samples collected from Asian countries since 1988 until 2010 with a focus on Malaysia and will provide needed information for further research in this field.

Identification of Organic Iodine Compounds and Their Transformation Products in Edible Iodized Salt Using Liquid Chromatography-High Resolution Mass Spectrometry.

PubMed

Yun, Lifen; Peng, Yue'e; Chang, Qing; Zhu, Qingxin; Guo, Wei; Wang, Yanxin

2017-07-05

The consumption of edible iodized salt is a key strategy to control and eliminate iodine deficiency disorders worldwide. We herein report the identification of the organic iodine compounds present in different edible iodized salt products using liquid chromatography combined with high resolution mass spectrometry. A total of 38 organic iodine compounds and their transformation products (TPs) were identified in seaweed iodine salt from China. Our experiments confirmed that the TPs were generated by the replacement of I atoms from organic iodine compounds with Cl atoms. Furthermore, the organic iodine compound contents in 4 seaweed iodine salt samples obtained from different manufacturers were measured, with significant differences in content being observed. We expect that the identification of organic iodine compounds in salt will be important for estimating the validity and safety of edible iodized salt products.

Methods of making organic compounds by metathesis

DOEpatents

Abraham, Timothy W.; Kaido, Hiroki; Lee, Choon Woo; Pederson, Richard L.; Schrodi, Yann; Tupy, Michael John

2015-09-01

Described are methods of making organic compounds by metathesis chemistry. The methods of the invention are particularly useful for making industrially-important organic compounds beginning with starting compositions derived from renewable feedstocks, such as natural oils. The methods make use of a cross-metathesis step with an olefin compound to produce functionalized alkene intermediates having a pre-determined double bond position. Once isolated, the functionalized alkene intermediate can be self-metathesized or cross-metathesized (e.g., with a second functionalized alkene) to produce the desired organic compound or a precursor thereto. The method may be used to make bifunctional organic compounds, such as diacids, diesters, dicarboxylate salts, acid/esters, acid/amines, acid/alcohols, acid/aldehydes, acid/ketones, acid/halides, acid/nitriles, ester/amines, ester/alcohols, ester/aldehydes, ester/ketones, ester/halides, ester/nitriles, and the like.

Concentrations in human blood of petroleum hydrocarbons associated with the BP/Deepwater Horizon oil spill, Gulf of Mexico.

PubMed

Sammarco, Paul W; Kolian, Stephan R; Warby, Richard A F; Bouldin, Jennifer L; Subra, Wilma A; Porter, Scott A

2016-04-01

During/after the BP/Deepwater Horizon oil spill, cleanup workers, fisherpersons, SCUBA divers, and coastal residents were exposed to crude oil and dispersants. These people experienced acute physiological and behavioral symptoms and consulted a physician. They were diagnosed with petroleum hydrocarbon poisoning and had blood analyses analyzed for volatile organic compounds; samples were drawn 5-19 months after the spill had been capped. We examined the petroleum hydrocarbon concentrations in the blood. The aromatic compounds m,p-xylene, toluene, ethylbenzene, benzene, o-xylene, and styrene, and the alkanes hexane, 3-methylpentane, 2-methylpentane, and iso-octane were detected. Concentrations of the first four aromatics were not significantly different from US National Health and Nutritional Examination Survey/US National Institute of Standards and Technology 95th percentiles, indicating high concentrations of contaminants. The other two aromatics and the alkanes yielded equivocal results or significantly low concentrations. The data suggest that single-ring aromatic compounds are more persistent in the blood than alkanes and may be responsible for the observed symptoms. People should avoid exposure to crude oil through avoidance of the affected region, or utilizing hazardous materials suits if involved in cleanup, or wearing hazardous waste operations and emergency response suits if SCUBA diving. Concentrations of alkanes and PAHs in the blood of coastal residents and workers should be monitored through time well after the spill has been controlled.