Land Application of Wastes: An Educational Program. Potentially Toxic Elements - Module 11.

ERIC Educational Resources Information Center

Clarkson, W. W.; And Others

Five elements are identified as being potentially hazardous in this module. These are boron, cadmium, copper, molybdenum, and nickel. The hazards to plants and animals posed by these elements are discussed in some detail. The sources of toxic elements in sewage and the factors that effect the uptake of toxic elements by sewage sludge are also…

A recent history of metal accumulation in the sediments of Rijeka harbor, Adriatic Sea, Croatia.

PubMed

Cukrov, Neven; Frančišković-Bilinski, Stanislav; Hlača, Bojan; Barišić, Delko

2011-01-01

We studied metal pollution in the sediments of Rijeka harbor, including anthropogenic influence during recent decades and at the present time. Sediment profiles were collected at ten sampling points. The concentrations of 63 elements in bulk sediment were obtained using ICP-MS, and the concentrations of selected elements were evaluated by statistical factor analyses. We also calculated metal-enrichment factors and geoaccumulation indices and constructed spatial-distribution maps. Mercury (Hg) was the heaviest pollutant, with concentrations exceeding 4 mg/kg. Silver (Ag) was the second most important pollutant, with constantly increasing values. The average concentrations of the most toxic elements were comparable to those found in sediments of other ports throughout the world, and their toxicity ranged from threshold values [chromium (Cr), arsenic (As)] and midrange-effect values [cadmium (Cd), lead (Pb), copper (Cu), zinc (Zn), nickel (Ni)] to extreme-effect values (Hg). Metal pollution has decreased during recent decades, except for Ag and barium (Ba). Copyright © 2010 Elsevier Ltd. All rights reserved.

Selective uptake of major and trace elements in Erica andevalensis, an endemic species to extreme habitats in the Iberian Pyrite Belt.

PubMed

Monaci, Fabrizio; Leidi, Eduardo O; Dolores, Mingorance Maria; Valdés, Benito Oliva; Rossini, Sabina Sabina; Bargagli, Roberto

2011-01-01

To assess the ecophysiological traits and the phytoremediation potential of the endemic heather Erica andevalensis, we determined the concentrations of major and trace elements in different plant parts and in rizosphere soils from Riotinto mining district (Huelva, Spain). The results showed that E. andevalensis may grow on substrates with very high As, Cu, Fe and Pb concentrations (up to 4114, 1050, 71900 and 15614 microg/g dry weight, respectively), very low availability of macro- and micronutrients and with pH values ranging from 3.3 to 4.9. In these harsh edaphic conditions E. andevalensis selectively absorbed and translocated essential nutrients and excludes potentially phytotoxic elements, which were accumulated in the root epidermis. The concentrations of major and trace elements in E. andevalensis aerial parts from the Riotinto mining district were in the normal range for plants; likewise other Erica species it accumulated Mn and only in a very polluted site we measured leaf concentrations of As and Pb within the excessive or toxic limits for plants. Differently from previous studies, which emphasized the soil pH and bioavailability of phytotoxic elements as the main stress factors, this study showed that in the Riotinto region, E. andevalensis can tolerate wide range of pH and toxic element concentrations; the harshest environments colonized by monospecific patches of this species were characterized above all by very low availability of nutrients. The extraordinary capability to adapt to these extreme habitats made E. andevalensis a priority species to promote the phytostabilization and the development of a self-sustaining vegetative cover on Riotinto mine tailings.

Characterization of selected bed-sediment-bound organic and inorganic contaminants and toxicity, Barnegat Bay and major tributaries, New Jersey, 2012

USGS Publications Warehouse

Romanok, Kristin M.; Reilly, Timothy J.; Lopez, Anthony R.; Trainor, John J.; Hladik, Michelle; Stanley, Jacob K.; Farrar, Daniel

2014-01-01

A study of bed-sediment toxicity and organic and inorganic contaminants was conducted by the U.S. Geological Survey (USGS) in cooperation with the New Jersey Department of Environmental Protection (NJDEP). Bed-sediment samples were collected once from 22 sites in Barnegat Bay and selected major tributaries during August–September 2012 and analyzed for toxicity and a suite of organic and inorganic contaminants by the USGS and the U.S. Army Corps of Engineers. Sampling sites were selected to coincide with an existing water-quality monitoring network used by the NJDEP and others in order to evaluate water-quality conditions in Barnegat Bay and the surrounding watershed. Two of the 22 sites are reference sites and are within or adjacent to the study area; bed-sediment samples from reference sites allow for comparisons of results for the Barnegat Bay watershed to results from less affected settings within the region. Toxicity testing was conducted by exposing the estuarine amphipod Leptocheirus plumulosus and the freshwater amphipod Hyalella azteca to sediments for 28 days, and the percent survival, difference in biomass, and individual dry weights were measured. Reproductive effects also were evaluated for estuarine samples. Bed-sediment samples from four sites within Barnegat Bay were subjected to a toxicity identification evaluation to determine probable causes of toxicity. Samples were analyzed for a suite of 94 currently-used pesticides, 21 legacy pesticides, 24 trace elements, 40 polycyclic aromatic hydrocarbons, 7 polychlorinated biphenyls (PCBs) as Arochlor mixtures, and 145 individual PCB congeners. Concentrations of detected compounds were compared to sediment-quality guidelines, where appropriate.

Content of trace elements and chromium speciation in Neem powder and tea infusions.

PubMed

Novotnik, Breda; Zuliani, Tea; Ščančar, Janez; Milačič, Radmila

2015-01-01

Total concentrations of selected trace elements in Neem powder and in Neem tea were determined by inductively coupled plasma mass spectrometry (ICP-MS). The data revealed that despite high total concentrations of the potentially toxic elements Al and Ni in Neem powder, their amounts dissolved in Neem tea were low. Total concentrations of the other toxic elements Pb, As and Cd were also very low and do not represent a health hazard. In contrast, total concentrations of the essential elements Fe, Cu, Zn, Se Mo and Cr in Neem powder were high and also considerable in Neem tea. Consuming one cup of Neem tea (2g per 200 mL of water) covers the recommended daily intakes for Cr and Se and represents an important source of Mo and Cu. Speciation analysis of Cr by high performance liquid chromatography (HPLC) coupled to ICP-MS with the use of enriched Cr isotopic tracers to follow species interconversions during the analytical procedure demonstrated that toxic Cr(VI) was not present either in Neem powder or in Neem tea. Its concentrations were below the limits of detection of the HPLC-ICP-MS procedure applied. The speciation analysis data confirmed that even Cr(VI) was added, it was rapidly reduced by the presence of antioxidants in Neem leaves. By the use of enriched Cr isotopic spike solutions it was also demonstrated that for obtaining reliable analytical data it is essential to apply the extraction procedures which prevent Cr species interconversions, or to correct for species transformation. Copyright © 2015 Elsevier GmbH. All rights reserved.

Anthroposophic lifestyle influences the concentration of metals in placenta and cord blood

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

Fagerstedt, Sara; Kippler, Maria; Scheynius, Annika

Allergic diseases develop in genetically susceptible individuals in a complex interplay with the environment, usually early in life. We have previously shown that the anthroposophic lifestyle is associated with reduced risk of allergic disease in children, but details on the influencing environmental factors are largely unknown. This study aims to elucidate if anthroposophic lifestyle influences fetal exposure to selected toxic and essential elements. Randomly selected non-smoking mothers with (n=40) and without (n=40) anthroposophic lifestyle from the prospective birth cohort ALADDIN were included. Concentrations of 12 toxic and essential elements were analyzed in full term placentas and in the erythrocyte fractionsmore » of maternal peripheral blood and of umbilical cord blood, using inductively coupled plasma mass spectrometry. Cadmium concentrations in maternal blood and placenta were significantly higher in mothers with an anthroposophic lifestyle (p<0.001), while concentrations in cord blood were generally low, irrespective of lifestyle. Cobalt concentrations were higher in both maternal blood, placenta and cord blood in the anthroposophic group. Lead concentrations were higher in maternal blood and cord blood, but not placenta, of mothers with anthroposophic lifestyle. Analysis of covariance, including lifestyle, parity, maternal age, gestational age, vegetarian diet, use of herbal medicine and occupation in the model, showed that mainly the anthroposophic lifestyle was significantly associated with cadmium concentrations. In conclusion, women with an anthroposophic lifestyle had higher concentrations of cadmium, cobalt and lead concentrations. Cadmium concentrations might have been influenced by a diet rich in vegetables and/or low iron status of the mothers. - Highlights: • Toxic elements in mother–newborn pairs in relation to anthroposophic lifestyle. • Anthroposophic lifestyle was associated with higher levels of cadmium, cobalt and lead. • A diet rich in vegetables and/or low iron status may explain observed findings. • Nine other elements showed no differences by lifestyle.« less

Reduced Toxicity Fuel Satellite Propulsion System

NASA Technical Reports Server (NTRS)

Schneider, Steven J. (Inventor)

2001-01-01

A reduced toxicity fuel satellite propulsion system including a reduced toxicity propellant supply for consumption in an axial class thruster and an ACS class thruster. The system includes suitable valves and conduits for supplying the reduced toxicity propellant to the ACS decomposing element of an ACS thruster. The ACS decomposing element is operative to decompose the reduced toxicity propellant into hot propulsive gases. In addition the system includes suitable valves and conduits for supplying the reduced toxicity propellant to an axial decomposing element of the axial thruster. The axial decomposing element is operative to decompose the reduced toxicity propellant into hot gases. The system further includes suitable valves and conduits for supplying a second propellant to a combustion chamber of the axial thruster, whereby the hot gases and the second propellant auto-ignite and begin the combustion process for producing thrust.

Reduced Toxicity Fuel Satellite Propulsion System Including Plasmatron

NASA Technical Reports Server (NTRS)

Schneider, Steven J. (Inventor)

2003-01-01

A reduced toxicity fuel satellite propulsion system including a reduced toxicity propellant supply for consumption in an axial class thruster and an ACS class thruster. The system includes suitable valves and conduits for supplying the reduced toxicity propellant to the ACS decomposing element of an ACS thruster. The ACS decomposing element is operative to decompose the reduced toxicity propellant into hot propulsive gases. In addition the system includes suitable valves and conduits for supplying the reduced toxicity propellant to an axial decomposing element of the axial thruster. The axial decomposing element is operative to decompose the reduced toxicity propellant into hot gases. The system further includes suitable valves and conduits for supplying a second propellant to a combustion chamber of the axial thruster. whereby the hot gases and the second propellant auto-ignite and begin the combustion process for producing thrust.

Body burdens, sources and interrelations of selected toxic and essential elements among the nine Cree First Nations of Eeyou Istchee, James Bay region of northern Quebec, Canada.

PubMed

Nieboer, Evert; Martin, Ian D; Liberda, Eric N; Dewailly, Eric; Robinson, Elizabeth; Tsuji, Leonard J S

2017-05-24

this article constitutes a report on the comprehensive Nituuchischaayihtitaau Aschii multi-community environment-and-health study conducted among the Cree peoples (Eeyouch) of northern Quebec, Canada. to interpret observed concentrations of a suite of chemical elements in a multi-media biological monitoring study in terms of sources and predictors. the concentrations of 5 essential and 6 toxic chemical elements were measured in whole blood, and/or in urine or hair by ICP-MS. Concentrations of essential elements are compared to those considered normal (i.e., required for good health) and, when toxic, deemed acceptable at specified concentrations in public health guidelines. Their dependence on age, sex, the specific community lived-in and diet were explored employing multivariate analysis of variance (MANOVA) involving new variables generated by principle component analysis (PCA) and correspondence analysis (CA). the 5 most prominent PCA axes explained 67.7% of the variation, compared to 93.0% by 6 main CA factors. Concentrations of the essential elements in whole blood (WB) and iodine(i) and arsenic (As) in urine were comparable to those reported in the recent Canadian Health Measures survey and are assigned to dietary sources. By contrast, WB cadmium (Cd) was elevated even when smoking was considered. Mercury (Hg) concentrations in WB and hair were also higher in adults, although comparable to those observed for other indigenous populations living at northern latitudes. Fish consumption was identified as the prominent source. Of the 5 coastal communities, all but one had lower Hg exposures than the four inland communities, presumably reflecting the type of fish consumed. Use of firearms and smoking were correlated with WB-lead (Pb). The concentrations of both Hg and Pb increased with age and were higher in men, while WB-Cd and smoking prevalence were higher in women when considering all communities. Hg and Pb were low in children and women of reproductive age, with few exceedances of health guidelines. Although individuals with T2D had somewhat lower WB-Cd, there is some indication that Cd may potentiate renal dysfunction in this subgroup. Plots of selected CA axes grouped those elements expected to be in a normal diet and distinguished them from those with well-known unique sources (especially Hg and As in hair; and Hg, Pb and Cd in WB). the use of multiple biological media in conjunction with the complementary PCA and CA approaches for constructing composite variables allowed a more detailed understanding of both the sources of the essential and toxic elements in body fluids and the dependencies of their observed concentrations on age, sex, community and diet.

Toxicity of nutritionally available selenium compounds in primary and transformed hepatocytes.

PubMed

Weiller, Markus; Latta, Markus; Kresse, Matthias; Lucas, Rudolf; Wendel, Albrecht

2004-09-01

The essential trace element selenium is also toxic at low doses. Since supplementation of selenium is discussed as cancer prophylaxis, we investigated whether or not bioavailable selenium compounds are selectively toxic on malignant cells by comparing primary and transformed liver cells as to the extent and mode of cell death. Sodium selenite and selenate exclusively induced necrosis in a concentration-dependent manner in all cell types investigated. In primary murine hepatocytes, the EC50 was 20 microM for selenite, 270 microM for selenate, and 30 microM for Se-methionine. In the human carcinoma cell line HepG2, the EC50 for selenite was 40 microM, and for selenate 1.1 mM, whereas Se-methionine was essentially non-toxic up to 10 mM. Similar results were found in murine Hepa1-6 cells. Exposure of primary murine cells to selenate or selenite resulted in increased lipid peroxidation. Toxicity was inhibited by superoxide dismutase plus catalase, indicating an important role for reactive oxygen intermediates. In primary hepatocytes, metabolical depletion of intracellular ATP by the ketohexose tagatose, significantly decreased the cytotoxicity of Se-methionine, while the one of selenite was increased. These data do not provide any in vitro evidence that bioavailable selenium compounds induce preferentially apoptotic cell death or selectively kill transformed hepatocytes.

INAA Application for Trace Element Determination in Biological Reference Material

NASA Astrophysics Data System (ADS)

Atmodjo, D. P. D.; Kurniawati, S.; Lestiani, D. D.; Adventini, N.

2017-06-01

Trace element determination in biological samples is often used in the study of health and toxicology. Determination change to its essentiality and toxicity of trace element require an accurate determination method, which implies that a good Quality Control (QC) procedure should be performed. In this study, QC for trace element determination in biological samples was applied by analyzing the Standard Reference Material (SRM) Bovine muscle 8414 NIST using Instrumental Neutron Activation Analysis (INAA). Three selected trace element such as Fe, Zn, and Se were determined. Accuracy of the elements showed as %recovery and precision as %coefficient of variance (%CV). The result showed that %recovery of Fe, Zn, and Se were in the range between 99.4-107%, 92.7-103%, and 91.9-112%, respectively, whereas %CV were 2.92, 3.70, and 5.37%, respectively. These results showed that INAA method is precise and accurate for trace element determination in biological matrices.

Reduced Toxicity Fuel Satellite Propulsion System Including Fuel Cell Reformer with Alcohols Such as Methanol

NASA Technical Reports Server (NTRS)

Schneider, Steven J. (Inventor)

2001-01-01

A reduced toxicity fuel satellite propulsion system including a reduced toxicity propellant supply for consumption in an axial class thruster and an ACS class thruster. The system includes suitable valves and conduits for supplying the reduced toxicity propellant to the ACS decomposing element of an ACS thruster. The ACS decomposing element is operative to decompose the reduced toxicity propellant into hot propulsive gases. In addition the system includes suitable valves and conduits for supplying the reduced toxicity propellant to an axial decomposing element of the axial thruster. The axial decomposing element is operative to decompose the reduced toxicity propellant into hot gases. The system further includes suitable valves and conduits for supplying a second propellant to a combustion chamber of the axial thruster, whereby the hot gases and the second propellant auto-ignite and begin the combustion process for producing thrust.

Heavy metals and essential elements in Italian cereals.

PubMed

Brizio, P; Benedetto, A; Squadrone, S; Curcio, A; Pellegrino, M; Ferrero, M; Abete, M C

2016-12-01

Crops intended for human nutrition and food production containing different essential trace elements, such as copper and zinc, could be contaminated by toxic metals like cadmium and lead. The interrelationship between micronutrients and contaminant trace elements in different cereals was investigated in North-western Italy, where both agricultural and industrial activities are present. Elemental concentrations in sampled cereals were assessed by inductively coupled plasma mass spectrometry (ICP-MS). Rice, oats and barley reached the highest median levels for Al, Cd and Pb content, while corn samples were less contaminated by toxic metals. Regarding essential elements highest median values of Cu and Zn were both found in barley, while Ni median content was higher in oats. Rice had the lowest median levels of essential elements. The correlation study between toxic and essential elements seemed to demonstrate fixed trends in analysed samples, corroborating the importance of a different diet to limit potential adverse effects caused by toxic elements.

Planning studies for measurement of chemical emissions in stack gases of coal-fired power plants. Final report

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

Barrett, W.J.; Gooch, J.P.; Dahlin, R.S.

1983-03-01

Airborne emissions from coal-fired power plants consist of sulfur, nitrogen, and carbon oxides, as well as traces of certain metals or elements, radionuclides, and organic compounds that have the potential of producing adverse health effects if inhaled. To assess this potential toxicity, samples must be obtained and characterized on the basis of quantity, their chemistry, and toxicity. Sample representativeness and use of proper chemical-biological procedures are the critical for providing input into current research directed toward source apportionment and inhalation toxicology. Obtaining a valid stack sample (gases and particles) from each of more than 1500 US coal-fired power plant ismore » not practical; consequently 33 plants have been selected, taking into account plant design and operating parameters that can affect the characteristics of stack chemical emissions. Since such a program has an estimated cost of $20 million over many years, it is recommended that the initial program consists of sampling only six of the 33 units, selected with EPRI guidance, at an estimated cost of $3.5 million over a 30 month period. The plan is directed at in-stack sampling, plume and atmospheric transformations being beyond the project scope. Various stack sampling methods are considered. For particles, a modified SASS train seems best, and for gases, either resin traps or impingers are probably best. Artifact formation must be minimized. Chemical analysis procedures are to be guided by the known toxicity of species present. Procedures are outlined for organics (volatile and nonvolatile), trace elements, inorganics, and gases. Bioassay methods are restricted to in vitro, subdivided into those assays that detect genetic and direct cellular toxicity.« less

Impact of secondary generated minerals on toxic element immobilization for air pollution control fly ash of a municipal solid waste incinerator.

PubMed

Kitamura, Hiroki; Dahlan, Astryd Viandila; Tian, Yu; Shimaoka, Takayuki; Yamamoto, Takashi; Takahashi, Fumitake

2018-05-12

Impacts of secondary generated minerals on mineralogical and physical immobilization of toxic elements were investigated for chelate-treated air pollution control (APC) fly ash of a municipal solid waste incinerator. Scanning electron microscope (SEM) observation showed that ettringite was generated after the moistening treatment with/without chelate. Although ettringite can incorporate toxic elements into its structure, elemental analysis by energy dispersive X-ray could not find concentrated points of toxic elements in ettringite structure. This implies that mineralogical immobilization of toxic element by the encapsulation to ettringite structure seems to be limited. Physical immobilization was also investigated by SEM observation of the same APC fly ash particles before and after the moistening treatment. The transfer of soluble elements was inhibited only when insoluble minerals such as gypsum were generated and covered the surface of fly ash particles. Neoformed insoluble minerals prevented soluble elements from leaching and transfer. However, such physical immobilization seems to be limited because insoluble mineral formation with surface coverage was monitored only one time of more than 20 observations. Although uncertainty owing to limited samples with limited observations should be considered, this study concludes that mineralogical and physical immobilization of toxic elements by secondary minerals is limited although secondary minerals are always generated on the surface of APC fly ash particles during chelate treatment.

Comparative toxicities of selected rare earth elements: Sea urchin embryogenesis and fertilization damage with redox and cytogenetic effects

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

Pagano, Giovanni, E-mail: gbpagano@tin.it; Guida, Marco; Siciliano, Antonietta

Background: Broad-ranging adverse effects are known for rare earth elements (REE), yet only a few studies tested the toxicity of several REE, prompting studies focusing on multi-parameter REE toxicity. Methods: Trichloride salts of Y, La, Ce, Nd, Sm, Eu and Gd were tested in Paracentrotus lividus sea urchin embryos and sperm for: (1) developmental defects in either REE-exposed larvae or in the offspring of REE-exposed sperm; (2) fertilization success; (3) mitotic anomalies in REE-exposed embryos and in the offspring of REE-exposed sperm, and (4) reactive oxygen species (ROS) formation, and malondialdehyde (MDA) and nitric oxide (NO) levels. Results: REEs affectedmore » P. lividus larvae with concentration-related increase in developmental defects, 10{sup −6} to 10{sup −4} M, ranking as: Gd(III)>Y(III)>La(III)>Nd(III)≅Eu(III)>Ce(III)≅Sm(III). Nominal concentrations of REE salts were confirmed by inductively coupled plasma mass spectrometry (ICP-MS). Significant increases in MDA levels, ROS formation, and NO levels were found in REE-exposed embryos. Sperm exposure to REEs (10{sup −5} to 10{sup −4} M) resulted in concentration-related decrease in fertilization success along with increase in offspring damage. Decreased mitotic activity and increased aberration rates were detected in REE-exposed embryos and in the offspring of REE-exposed sperm. Conclusion: REE-associated toxicity affecting embryogenesis, fertilization, cytogenetic and redox endpoints showed different activities of tested REEs. Damage to early life stages, along with redox and cytogenetic anomalies should be the focus of future REE toxicity studies. - Highlights: • Seven rare earth elements exerted different effects on sea urchin early life stages. • Embryo-, spermio- and mitotoxicity, and oxidative/ nitrosative stress were found. • Nominal vs. analytical REE concentrations were checked. • Comparative toxicities were evaluated for the different REE.« less

Batch leaching tests of motherboards to assess environmental contamination by bromine, platinum group elements and other selected heavy metals.

PubMed

Almeida, César; Grosselli, Melina; González, Patricia; Martínez, Dante; Gil, Raúl

2016-02-01

In this study, a batch leaching test was executed to evaluate the toxicity associated with chemicals contained in motherboards. The leaching solutions used were distilled water, nitric acid, acetic acid and synthetic acid rain solution. A total of 21 elements including Ag, As, Au, Br, Cd, Co, Cr, Cu, Hf, Ir, Mn, Ni, Os, Pb, Pd, Pt, Rd, Rh, Se, U and Zn were analyzed. In this study, the pH values of all the leachates fell within the range of 2.33-4.88. The highest concentrations of metals were obtained from the acid rain solution, whilst the maximum value of bromine was achieved with solution of acetic acid. Appreciable concentrations of platinum group elements were detected with concentrations around 3.45, 1.43, 1.21 and 22.19 µg L(-1) for Ir, Pd, Pt and Rh, respectively. The different leaching of the motherboards revealed the predominant presence of the toxic substances in the leached from the e-waste. Copyright © 2015 Elsevier Ltd. All rights reserved.

Interspecies quantitative structure-activity relationships (QSARs) for eco-toxicity screening of chemicals: the role of physicochemical properties.

PubMed

Furuhama, A; Hasunuma, K; Aoki, Y

2015-01-01

In addition to molecular structure profiles, descriptors based on physicochemical properties are useful for explaining the eco-toxicities of chemicals. In a previous study we reported that a criterion based on the difference between the partition coefficient (log POW) and distribution coefficient (log D) values of chemicals enabled us to identify aromatic amines and phenols for which interspecies relationships with strong correlations could be developed for fish-daphnid and algal-daphnid toxicities. The chemicals that met the log D-based criterion were expected to have similar toxicity mechanisms (related to membrane penetration). Here, we investigated the applicability of log D-based criteria to the eco-toxicity of other kinds of chemicals, including aliphatic compounds. At pH 10, use of a log POW - log D > 0 criterion and omission of outliers resulted in the selection of more than 100 chemicals whose acute fish toxicities or algal growth inhibition toxicities were almost equal to their acute daphnid toxicities. The advantage of log D-based criteria is that they allow for simple, rapid screening and prioritizing of chemicals. However, inorganic molecules and chemicals containing certain structural elements cannot be evaluated, because calculated log D values are unavailable.

The use of inductively coupled plasma mass spectrometry (ICP-MS) for the determination of toxic and essential elements in different types of food samples

NASA Astrophysics Data System (ADS)

Voica, C.; Dehelean, A.; Kovacs, M. H.

2012-02-01

Food is the primary source of essential elements for humans and it is an important source of exposure to toxic elements. In this context, levels of essential and toxic elements must be determined routinely in consumed food products. The content of trace elements (As, Pb, Cu, Cd, Zn, Sn, Hg) in different types of food samples (e.g. rice, bread, sugar, cheese, milk, butter, wheat, coffee, chocolate, biscuits pasta, etc.) was determined, using inductively coupled plasma mass spectrometry (ICP-MS). Trace element contents in some foods were higher than maximum permissible levels of toxic metals in human food (Cd in bread, Zn in cheese, Cu in coffee, Hg in carrots and peppers).

Toxicity of trace element and salinity mixtures to striped bass (Morone saxatilis) and Daphnia magna

USGS Publications Warehouse

Dwyer, F.J.; Burch, S.A.; Ingersoll, C.G.; Hunn, J.B.

1992-01-01

Acute toxicity tests with reconstituted water were conducted to investigate the relationship between water hardness, salinity, and a mixture of trace elements found in irrigation drain waters entering Stillwater Wildlife Management Area (SWMA), near Fallon, Nevada. The SWMA has been the site of many fish kills in recent years, and previous toxicity studies indicated that one drain water, Pintail Bay, was acutely toxic to organisms acclimated or cultured in fresh water or salt water. This toxicity could reflect both the ionic composition of this saline water and the presence of trace elements. The lowest water salinity tested with Daphnia magna was near the upper salinity tolerance of these organisms; therefore, we were unable to differentiate between the toxic effects of ion composition and those of trace elements. In toxicity tests conducted with striped bass (Morone saxatilis), we found that the extent to which salinity was lethal to striped bass depended on the ion composition of that salinity. Survival of striped bass increased as hardness increased. In addition, a trace element mixture was toxic to striped bass, even though the concentrations of individual elements were below expected acutely lethal concentrations. Although salinity is an important water quality characteristic, the ionic composition of the water must be considered when one assesses the hazard of irrigation drain waters to aquatic organisms.

ICP-MS: Analytical Method for Identification and Detection of Elemental Impurities.

PubMed

Mittal, Mohini; Kumar, Kapil; Anghore, Durgadas; Rawal, Ravindra K

2017-01-01

Aim of this article is to review and discuss the currently used quantitative analytical method ICP-MS, which is used for quality control of pharmaceutical products. ICP-MS technique has several applications such as determination of single elements, multi element analysis in synthetic drugs, heavy metals in environmental water, trace element content of selected fertilizers and dairy manures. ICP-MS is also used for determination of toxic and essential elements in different varieties of food samples and metal pollutant present in the environment. The pharmaceuticals may generate impurities at various stages of development, transportation and storage which make them risky to be administered. Thus, it is essential that these impurities must be detected and quantified. ICP-MS plays an important function in the recognition and revealing of elemental impurities. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Distribution of uranium, thorium and some stable trace and toxic elements in human hair and nails in Niška Banja Town, a high natural background radiation area of Serbia (Balkan Region, South-East Europe).

PubMed

Sahoo, S K; Žunić, Z S; Kritsananuwat, R; Zagrodzki, P; Bossew, P; Veselinovic, N; Mishra, S; Yonehara, H; Tokonami, S

2015-07-01

Human hair and nails can be considered as bio-indicators of the public exposure to certain natural radionuclides and other toxic metals over a long period of months or even years. The level of elements in hair and nails usually reflect their levels in other tissues of body. Niška Banja, a spa town located in southern Serbia, with locally high natural background radiation was selected for the study. To assess public exposure to the trace elements, hair and nail samples were collected and analyzed. The concentrations of uranium, thorium and some trace and toxic elements (Mn, Ni, Cu, Sr, Cd, and Cs) were determined using inductively coupled plasma mass spectrometry (ICP-MS). U and Th concentrations in hair varied from 0.0002 to 0.0771 μg/g and from 0.0002 to 0.0276 μg/g, respectively. The concentrations in nails varied from 0.0025 to 0.0447 μg/g and from 0.0023 to 0.0564 μg/g for U and Th, respectively. We found significant correlations between some elements in hair and nails. Also indications of spatial clustering of high values could be found. However, this phenomenon as well as the large variations in concentrations of heavy metals in hair and nail could not be explained. As hypotheses, we propose possible exposure pathways which may explain the findings, but the current data does not allow testing them. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Nickel toxicity in the hepatopancreas of an isopod Porcellio scaber ( Oniscidea)

NASA Astrophysics Data System (ADS)

Tarnawska, M.; Migula, P.; Przybyłowicz, W.; Mesjasz-Przybyłowicz, J.; Augustyniak, M.

2007-07-01

This study is focused on recognizing how the functional role of hepatopancreas, the main metal storage organ in woodlice, is affected by the excess of nickel, a toxic element to soil invertebrates. Chronic Ni toxicity (24 weeks) was studied on four groups of woodlice kept on dry shredded maple leaves contaminated with Ni at average concentrations of 0.1 μg g -1 (control), 8.0 μg g -1 (Ni1), 75 μg g -1 (Ni2) and 270 μg g -1(Ni3) dry weight. Micro-PIXE mapping of elemental distribution in the hepatopancreas of the Porcellio scaber woodlice was used to study relations between nickel and other elements in individuals exposed to different metal concentrations in the diet. Data were processed using GeoPIXE II software. Transmission electron microscopy (TEM) was used to check the relations between ultrastructural changes in hepatopancreatic cells and nickel tissue burden. Elemental mapping showed a dose-related nickel bioaccumulation in the hepatopancreas at concentrations from 3 μg g -1 (uncontaminated control animals) to nearly 840 μg g -1 (Ni3). Generally, nickel was distributed uniformly in small aggregations. A combined evaluation of elemental maps and electronograms showed that aggregations of nickel in arbitrarily selected micro-areas in PIXE maps could be the granular structures observed in TEM electronograms. The mechanism of Ni sequestration in the hepatopancreas could be similar to this used for cadmium or lead. The sequences of ultrastructural changes, which follow the increased burdens of Ni in the hepatopancreatic cells, were: the increase of intracellular electron-dense granules, increase in the number of myelin-like structures, intensified mitochondrial swelling and appearance of concentrically arranged, rough endoplasmic reticulum.

Reconnaissance of chemical and physical characteristics of selected bottom sediments of the Caloosahatchee River and estuary, tributaries, and contiguous bays, Lee County, Florida, July 20-30, 1998

USGS Publications Warehouse

Fernandez, Mario; Marot, M.E.; Holmes, C.W.

1999-01-01

This report summarizes a reconnaissance study, conducted July 20-30, 1998, of chemical and physical characteristics of recently deposited bottom sediments in the Caloosahatchee River and Estuary. Recently deposited sediments were identified using an isotopic chronometer, Beryllium-7 (7Be), a short-lived radioisotope. Fifty-nine sites were sampled in an area that encompasses the Caloosahatchee River (River) about three miles upstream from the Franklin Lock (S-79), the entire tidally affected length of the river (estuary), and the contiguous water bodies of Matlacha Pass, San Carlos Bay, Estero Bay, Tarpon Bay, and Pine Island Sound in Lee County, Florida. Bottom sediments were sampled for 7Be at 59 sites. From the results of the 7Be analysis, 30 sites were selected for physical and chemical analysis. Sediments were analyzed for particle size, total organic carbon (TOC), trace elements, and toxic organic compounds, using semiquantitative methods for trace elements and organic compounds. The semiquantitative scans of trace elements indicated that cadmium, copper, lead, and zinc concentrations, when normalized to aluminum, were above the natural background range at 24 of 30 sites. Particle size and TOC were used to characterize sediment deposition patterns and organic content. Pesticides, polychlorinated biphenyls (PCBs), and carcinogenic polycyclic aromatic hydrocarbons (CaPAHs) were determined at 30 sites using immunoassay analysis. The semiquantitative immunoassay analyses of toxic organic compounds indicated that all of the samples contained DDT, cyclodienes as chlordane (pesticides), and CaPAHs. PCBs were not detected. Based on analyses of the 30 sites, sediments at 10 of these sites were analyzed for selected trace elements and toxic organic compounds, including pesticides, PCBs, and PAHs, using quantitative laboratory procedures. No arsenic or cadmium was detected. Zinc was detected at two sites with concentrations greater than the lower limit of the range of sediment contaminant concentrations that are usually or always associated with adverse effects (Florida Department of Environmental Protection's Sediment Quality Assessment Guidelines). Organochlorine pesticides were detected at four sites at concentrations below the reporting limits; there were no organophosphorus pesticides or PCBs detected. PAHs were detected at eight sites; however, only four sites had concentrations above the reporting limit.

Non-toxic invert analog glass compositions of high modulus

NASA Technical Reports Server (NTRS)

Bacon, J. F. (Inventor)

1974-01-01

Glass compositions having a Young's modulus of at least 15 million psi are described. They and a specific modulus of at least 110 million inches consist essentially of, in mols, 15 to 40% SiO2, 6 to 15% Li2O, 24 to 45% of at least two bivalent oxides selected from the group consisting of Ca, NzO, MgO and CuO; 13 to 39% of at least two trivalent oxides selected from the group consisting of Al2O3, Fe2O3, B2O3, La2O3, and Y2O3 and up to 15% of one or more tetravelent oxides selected from the group consisting of ZrO2, TiO2 and CeO2. The high modulus, low density glass compositions contain no toxic elements. The composition, glass density, Young's modulus, and specific modulus for 28 representative glasses are presented. The fiber modulus of five glasses are given.

Synthetic Developments of Nontoxic Quantum Dots.

PubMed

Das, Adita; Snee, Preston T

2016-03-03

Semiconductor nanocrystals, or quantum dots (QDs), are candidates for biological sensing, photovoltaics, and catalysis due to their unique photophysical properties. The most studied QDs are composed of heavy metals like cadmium and lead. However, this engenders concerns over heavy metal toxicity. To address this issue, numerous studies have explored the development of nontoxic (or more accurately less toxic) quantum dots. In this Review, we select three major classes of nontoxic quantum dots composed of carbon, silicon and Group I-III-VI elements and discuss the myriad of synthetic strategies and surface modification methods to synthesize quantum dots composed of these material systems. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Vitamin D, Essential Minerals, and Toxic Elements: Exploring Interactions between Nutrients and Toxicants in Clinical Medicine

PubMed Central

Schwalfenberg, Gerry K.; Genuis, Stephen J.

2015-01-01

In clinical medicine, increasing attention is being directed towards the important areas of nutritional biochemistry and toxicant bioaccumulation as they relate to human health and chronic disease. Optimal nutritional status, including healthy levels of vitamin D and essential minerals, is requisite for proper physiological function; conversely, accrual of toxic elements has the potential to impair normal physiology. It is evident that vitamin D intake can facilitate the absorption and assimilation of essential inorganic elements (such as calcium, magnesium, copper, zinc, iron, and selenium) but also the uptake of toxic elements (such as lead, arsenic, aluminum, cobalt, and strontium). Furthermore, sufficiency of essential minerals appears to resist the uptake of toxic metals. This paper explores the literature to determine a suitable clinical approach with regard to vitamin D and essential mineral intake to achieve optimal biological function and to avoid harm in order to prevent and overcome illness. It appears preferable to secure essential mineral status in conjunction with adequate vitamin D, as intake of vitamin D in the absence of mineral sufficiency may result in facilitation of toxic element absorption with potential adverse clinical outcomes. PMID:26347061

Analysis and prediction of structure-reactive toxicity relationships of substituted aromatic compounds

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

Liu, Z.T.; Wang, L.S.; Chen, S.P.

1996-12-31

The fundamental differentiation of toxicity is between reactive and nonreactive toxicity. Reactive toxicity is associated with a specific mechanism for the reaction with an enzyme or inhibition of a metabolic pathway, and nonreactive toxicity is related directly to the quantity of toxicant acting upon the cell. The quantitative structure-activity relationships (QSARs) have been successfully used in the nonreactive toxicity, such as prediction of the toxicity of nonreactive compounds based on their solubility in the lipids of organisms. The elements of molecular structure that are most closely related to nonreactive toxicity are those that describe the partitioning of the toxicant intomore » the organism, while QSARs for the reactive toxicity are less common in the environmental toxicology literature. With the recent increase in the use of synthetic substituted benzenes as industrial chemicals, the accurate analysis of the effect of reactive toxic chemicals has become recognized with QSAR. For this purpose, we selected the fish (Carassias auratus) as the test organism, measured the acute toxicity of 50% lethal concentration (LC{sub 50}) of the chemicals and the adenosine triphosphate (ATP) content of the liver cells for the organism. These determined the relationships of the acute toxicity of some substituted benzenes with their physicochemical structural parameters. The effects on the ATP content was also compared to predict biological reactivities of the chemicals, so as to find some clues to explain the mode of mechanism of the toxicity. 17 refs., 1 tab.« less

Application of Hyphenated Techniques in Speciation Analysis of Arsenic, Antimony, and Thallium

PubMed Central

Michalski, Rajmund; Szopa, Sebastian; Jabłońska, Magdalena; Łyko, Aleksandra

2012-01-01

Due to the fact that metals and metalloids have a strong impact on the environment, the methods of their determination and speciation have received special attention in recent years. Arsenic, antimony, and thallium are important examples of such toxic elements. Their speciation is especially important in the environmental and biomedical fields because of their toxicity, bioavailability, and reactivity. Recently, speciation analytics has been playing a unique role in the studies of biogeochemical cycles of chemical compounds, determination of toxicity and ecotoxicity of selected elements, quality control of food products, control of medicines and pharmaceutical products, technological process control, research on the impact of technological installation on the environment, examination of occupational exposure, and clinical analysis. Conventional methods are usually labor intensive, time consuming, and susceptible to interferences. The hyphenated techniques, in which separation method is coupled with multidimensional detectors, have become useful alternatives. The main advantages of those techniques consist in extremely low detection and quantification limits, insignificant interference, influence as well as high precision and repeatability of the determinations. In view of their importance, the present work overviews and discusses different hyphenated techniques used for arsenic, antimony, and thallium species analysis, in different clinical, environmental and food matrices. PMID:22654649

A novel microbial fuel cell sensor with a gas diffusion biocathode sensing element for water and air quality monitoring.

PubMed

Jiang, Yong; Liang, Peng; Huang, Xia; Ren, Zhiyong Jason

2018-07-01

Toxicity monitoring is essential for the protection of public health and ecological safety. Microbial fuel cell (MFC) sensors demonstrated good potential in toxicity monitoring, but current MFC sensors can only be used for anaerobic water monitoring. In this study, a novel gas diffusion (GD)-biocathode sensing element was fabricated using a simple method. The GD-biocathode MFC sensor can directly be used for formaldehyde detection (from 0.0005% to 0.005%) in both aerobic and anaerobic water bodies. Electrochemical analysis indicated that the response by the sensor was caused by the toxic inhibition to the microbial activity for the oxygen reduction reaction (ORR). This study for the first time demonstrated that the GD-biocathode MFC sensor has a detection limit of 20 ppm for formaldehyde and can be used to monitor air pollution. Selective sensitivity to formaldehyde was not achieved as the result of using a mixed-culture, which confirms that it can serve as a generic biosensor for monitoring gaseous pollutants. This study expands the realm of knowledge for MFC sensor applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

Selecting surrogate endpoints for estimating pesticide effects on avian reproductive success.

PubMed

Bennett, Richard S; Etterson, Matthew A

2013-10-01

A Markov chain nest productivity model (MCnest) has been developed for projecting the effects of a specific pesticide-use scenario on the annual reproductive success of avian species of concern. A critical element in MCnest is the use of surrogate endpoints, defined as measured endpoints from avian toxicity tests that represent specific types of effects possible in field populations at specific phases of a nesting attempt. In this article, we discuss the attributes of surrogate endpoints and provide guidance for selecting surrogates from existing avian laboratory tests as well as other possible sources. We also discuss some of the assumptions and uncertainties related to using surrogate endpoints to represent field effects. The process of explicitly considering how toxicity test results can be used to assess effects in the field helps identify uncertainties and data gaps that could be targeted in higher-tier risk assessments. © 2013 SETAC.

Ecological effects and environmental fate of solid rocket exhaust

NASA Technical Reports Server (NTRS)

Nimmo, B.; Stout, I. J.; Mickus, J.; Vickers, D.; Madsen, B.

1974-01-01

Specific target processes were classified as to the chemical, chemical-physical, and biological reactions and toxic effects of solid rocket emissions within selected ecosystems at Kennedy Space Center. Exposure of Citris seedlings, English peas, and bush beans to SRM exhaust under laboratory conditions demonstrated reduced growth rates, but at very high concentrations. Field studies of natural plant populations in three diverse ecosystems failed to reveal any structural damage at the concentration levels tested. Background information on elemental composition of selected woody plants from two terrestrial ecosystems is reported. LD sub 50 for a native mouse (peromysous gossypinus) exposed to SRM exhaust was determined to be 50 ppm/g body weight. Results strongly indicate that other components of the SRM exhaust act synergically to enhance the toxic effects of HCl gas when inhaled. A brief summary is given regarding the work on SRM exhaust and its possible impact on hatchability of incubating bird eggs.

Biological toxicity of lanthanide elements on algae.

PubMed

Tai, Peidong; Zhao, Qing; Su, Dan; Li, Peijun; Stagnitti, Frank

2010-08-01

The biological toxicity of lanthanides on marine monocellular algae was investigated. The specific objective of this research was to establish the relationship between the abundance in the seawater of lanthanides and their biological toxicities on marine monocellular algae. The results showed that all single lanthanides had similar toxic effects on Skeletonema costatum. High concentrations of lanthanides (29.04+/-0.61 micromol L(-1)) resulted in 50% reduction in growth of algae compared to the controls (0 micromol L(-1)) after 96 h (96 h-EC50). The biological toxicity of 13 lanthanides on marine monocellular algae was unrelated with the abundance of different lanthanide elements in nature, and the "Harkins rule" was not appropriate for the lanthanides. A mixed solution that contained equivalent concentrations of each lanthanide element had the same inhibition effect on algae cells as each individual lanthanide element at the same total concentration. This phenomenon is unique compared to the groups of other elements in the periodic table. Hence, we speculate that the monocellular organisms might not be able to sufficiently differentiate between the almost chemically identical lanthanide elements. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Global transcriptomic responses of Escherichia coli K-12 to volatile organic compounds.

PubMed

Yung, Pui Yi; Grasso, Letizia Lo; Mohidin, Abeed Fatima; Acerbi, Enzo; Hinks, Jamie; Seviour, Thomas; Marsili, Enrico; Lauro, Federico M

2016-01-28

Volatile organic compounds (VOCs) are commonly used as solvents in various industrial settings. Many of them present a challenge to receiving environments, due to their toxicity and low bioavailability for degradation. Microorganisms are capable of sensing and responding to their surroundings and this makes them ideal detectors for toxic compounds. This study investigates the global transcriptomic responses of Escherichia coli K-12 to selected VOCs at sub-toxic levels. Cells grown in the presence of VOCs were harvested during exponential growth, followed by whole transcriptome shotgun sequencing (RNAseq). The analysis of the data revealed both shared and unique genetic responses compared to cells without exposure to VOCs. Results suggest that various functional gene categories, for example, those relating to Fe/S cluster biogenesis, oxidative stress responses and transport proteins, are responsive to selected VOCs in E. coli. The differential expression (DE) of genes was validated using GFP-promoter fusion assays. A variety of genes were differentially expressed even at non-inhibitory concentrations and when the cells are at their balanced-growth. Some of these genes belong to generic stress response and others could be specific to VOCs. Such candidate genes and their regulatory elements could be used as the basis for designing biosensors for selected VOCs.

Global transcriptomic responses of Escherichia coli K-12 to volatile organic compounds

PubMed Central

Yung, Pui Yi; Grasso, Letizia Lo; Mohidin, Abeed Fatima; Acerbi, Enzo; Hinks, Jamie; Seviour, Thomas; Marsili, Enrico; Lauro, Federico M.

2016-01-01

Volatile organic compounds (VOCs) are commonly used as solvents in various industrial settings. Many of them present a challenge to receiving environments, due to their toxicity and low bioavailability for degradation. Microorganisms are capable of sensing and responding to their surroundings and this makes them ideal detectors for toxic compounds. This study investigates the global transcriptomic responses of Escherichia coli K-12 to selected VOCs at sub-toxic levels. Cells grown in the presence of VOCs were harvested during exponential growth, followed by whole transcriptome shotgun sequencing (RNAseq). The analysis of the data revealed both shared and unique genetic responses compared to cells without exposure to VOCs. Results suggest that various functional gene categories, for example, those relating to Fe/S cluster biogenesis, oxidative stress responses and transport proteins, are responsive to selected VOCs in E. coli. The differential expression (DE) of genes was validated using GFP-promoter fusion assays. A variety of genes were differentially expressed even at non-inhibitory concentrations and when the cells are at their balanced-growth. Some of these genes belong to generic stress response and others could be specific to VOCs. Such candidate genes and their regulatory elements could be used as the basis for designing biosensors for selected VOCs. PMID:26818886

Geographic distribution of selected elements in the livers of polar bears from Greenland, Canada and the United States.

PubMed

Rush, Scott A; Borgå, Katrine; Dietz, Rune; Born, Erik W; Sonne, Christian; Evans, Thomas; Muir, Derek C G; Letcher, Robert J; Norstrom, Ross J; Fisk, Aaron T

2008-06-01

To assess geographic distributions of elements in the Arctic we compared essential and non-essential elements in the livers of polar bears (Ursus maritimus) collected from five regions within Canada in 2002, in Alaska between 1994 and 1999 and from the northwest and east coasts of Greenland between 1988 and 2000. As, Hg, Pb and Se varied with age, and Co and Zn with gender, which limited spatial comparisons across all populations to Cd, which was highest in Greenland bears. Collectively, geographic relationships appeared similar to past studies with little change in concentration over time in Canada and Greenland for most elements; Hg and Se were higher in some Canadian populations in 2002 as compared to 1982 and 1984. Concentrations of most elements in the polar bears did not exceed toxicity thresholds, although Cd and Hg exceeded levels correlated with the formation of hepatic lesions in laboratory animals.

Acute toxicity of arsenic and oxidative stress responses in the embryonic development of the common South American toad Rhinella arenarum.

PubMed

Mardirosian, Mariana Noelia; Lascano, Cecilia Inés; Ferrari, Ana; Bongiovanni, Guillermina Azucena; Venturino, Andrés

2015-05-01

Arsenic (As), a natural element of ecological relevance, is found in natural water sources throughout Argentina in concentrations between 0.01 mg/L and 15 mg/L. The autochthonous toad Rhinella arenarum was selected to study the acute toxicity of As and the biochemical responses elicited by the exposure to As in water during its embryonic development. The median lethal concentration (LC50) value averaged 24.3 mg/L As and remained constant along the embryonic development. However, As toxicity drastically decreased when embryos were exposed from heartbeat-stage on day 4 of development, suggesting the onset of detoxification mechanisms. Given the environmental concentrations of As in Argentina, there is a probability of exceeding lethal levels at 1% of sites. Arsenic at sublethal concentrations caused a significant decrease in the total antioxidant potential but generated an increase in endogenous glutathione (GSH) content and glutathione S-transferase (GST) activity. This protective response might prevent a deeper decline in the antioxidant system and further oxidative damage. Alternatively, it might be linked to As conjugation with GSH for its excretion. The authors conclude that toad embryos are more sensitive to As during early developmental stages and that relatively high concentrations of this toxic element are required to elicit mortality, but oxidative stress may be an adverse effect at sublethal concentrations. © 2014 SETAC.

Toxic elements and associations with hematology, plasma biochemistry, and protein electrophoresis in nesting loggerhead sea turtles (Caretta caretta) from Casey Key, Florida.

PubMed

Perrault, Justin R; Stacy, Nicole I; Lehner, Andreas F; Poor, Savannah K; Buchweitz, John P; Walsh, Catherine J

2017-12-01

Toxic elements (arsenic, cadmium, lead, mercury, selenium, thallium) are a group of contaminants that are known to elicit developmental, reproductive, general health, and immune system effects in reptiles, even at low concentrations. Reptiles, including marine turtles, are susceptible to accumulation of toxic elements due to their long life span, low metabolic rate, and highly efficient conversion of prey into biomass. The objectives of this study were to (1) document concentrations of arsenic, cadmium, lead, mercury, selenium, and thallium in whole blood and keratin from nesting loggerhead sea turtles (Caretta caretta) from Casey Key, Florida and document correlations thereof and (2) correlate whole blood toxic element concentrations to various hematological and plasma biochemistry analytes. Baselines for various hematological and plasma analytes and toxic elements in whole blood and keratin (i.e., scute) in nesting loggerheads are documented. Various correlations between the toxic elements and hematological and plasma biochemistry analytes were identified; however, the most intriguing were negative correlations between arsenic, cadmium, lead, and selenium with and α- and γ-globulins. Although various extrinsic and intrinsic variables such as dietary and feeding changes in nesting loggerheads need to be considered, this finding may suggest a link to altered humoral immunity. This study documents a suite of health variables of nesting loggerheads in correlation to contaminants and identifies the potential of toxic elements to impact the overall health of nesting turtles, thus presenting important implications for the conservation and management of this species. Copyright © 2017 Elsevier Ltd. All rights reserved.

The phytoremediation potential of native plants on New Zealand dairy farms.

PubMed

Hahner, Jason L; Robinson, Brett H; Hong-Tao, Zhong; Dickinson, Nicholas M

2014-01-01

Ecological restoration of marginal land and riparian zones in agricultural landscapes in New Zealand enhances the provision of above-ground ecosystem services. We investigated whether native endemic plant assemblages have remediation potential, through modifying soil nutrient and trace element mobility. Analysis of native plant foliage in situ indicated that selective uptake of a range of commonly deficient trace elements including Zn, B, Cu, Mn and Co could provide a browse crop to avoid deficiencies of these elements in livestock, although some native plants may enhance the risk of Mo and Cd toxicity. Native plant rhizospheres were found to modify soil physico-chemistry and are likely to influence lateral and vertical fluxes of chemical elements in drainage waters. Native plants on marginal land in agricultural landscapes could add value to dairy production systems whilst helping to resolve topical environmental issues.

Comparative analytical study of the selected wine varieties grown in Montenegro.

PubMed

Đorđević, Neda O; Novaković, Miroslav M; Pejin, Boris; Mutić, Jelena J; Vajs, Vlatka E; Pajović, Snežana B; Tešević, Vele V

2017-08-01

Samples of the selected red wine varieties grown in Montenegro (Merlot, Cabernet Sauvignon and Vranac; vintages 2010-2012) were compared according to total phenolic content, anti-DPPH radical activity, phenolic profile and elemental composition. All the samples showed profound anti-DPPH radical activity, due to high content of total phenolic compounds (R = 0.92). The most abundant phenolics were catechin and gallic acid with the highest values recorded for Merlot 2012 (43.22 and 28.65 mg/L, respectively). In addition to this, the content of essential elements including the potentially toxic ones was within healthy (safe) level for all the samples analysed. This study has actually pointed out Merlot wine variety as the best quality one, though all three varieties may be used as safe and health-promoting nutritional products.

Comparative toxicities of selected rare earth elements: Sea urchin embryogenesis and fertilization damage with redox and cytogenetic effects.

PubMed

Pagano, Giovanni; Guida, Marco; Siciliano, Antonietta; Oral, Rahime; Koçbaş, Fatma; Palumbo, Anna; Castellano, Immacolata; Migliaccio, Oriana; Thomas, Philippe J; Trifuoggi, Marco

2016-05-01

Broad-ranging adverse effects are known for rare earth elements (REE), yet only a few studies tested the toxicity of several REE, prompting studies focusing on multi-parameter REE toxicity. Trichloride salts of Y, La, Ce, Nd, Sm, Eu and Gd were tested in Paracentrotus lividus sea urchin embryos and sperm for: (1) developmental defects in either REE-exposed larvae or in the offspring of REE-exposed sperm; (2) fertilization success; (3) mitotic anomalies in REE-exposed embryos and in the offspring of REE-exposed sperm, and (4) reactive oxygen species (ROS) formation, and malondialdehyde (MDA) and nitric oxide (NO) levels. REEs affected P. lividus larvae with concentration-related increase in developmental defects, 10(-6) to 10(-4)M, ranking as: Gd(III)>Y(III)>La(III)>Nd(III)≅Eu(III)>Ce(III)≅Sm(III). Nominal concentrations of REE salts were confirmed by inductively coupled plasma mass spectrometry (ICP-MS). Significant increases in MDA levels, ROS formation, and NO levels were found in REE-exposed embryos. Sperm exposure to REEs (10(-5) to 10(-4)M) resulted in concentration-related decrease in fertilization success along with increase in offspring damage. Decreased mitotic activity and increased aberration rates were detected in REE-exposed embryos and in the offspring of REE-exposed sperm. REE-associated toxicity affecting embryogenesis, fertilization, cytogenetic and redox endpoints showed different activities of tested REEs. Damage to early life stages, along with redox and cytogenetic anomalies should be the focus of future REE toxicity studies. Copyright © 2016 Elsevier Inc. All rights reserved.

Determination of toxic inorganic elements pollution in ground waters of Kahuta Industrial Triangle Islamabad, Pakistan using inductively coupled plasma mass spectrometry.

PubMed

Kausar, Rubina; Ahmad, Zulfiqar

2009-10-01

The present study deals with the ground water quality assessment in Kahuta Industrial Triangle Islamabad, Pakistan. The objective of the study was to assess ground water quality against the drinking water standards for various toxic inorganic elements. Representative groundwater samples were collected and analyzed in the Water Quality Laboratory of Pakistan Council of Research in Water Resources (PCRWR) at Islamabad, Pakistan. The samples were run on ICP-MS (Inductively coupled plasma mass spectrometry), which has the capability to separate and quantify 70 elements at a time. One of the finding of study is that ICP-MS is a very good tool to analyze broad range of toxic inorganic elements to the level of parts per billion (ppb). World Health Organization drinking water standards shows that these toxic inorganic elements such as heavy metals even at this concentration level (ppb) are injurious to human health. This analysis indicated pollution of various toxic elements including Selenium. Vertical leachate through industrial waste septic tanks is identified as major cause of groundwater pollution in the Industrial Triangle. Monitoring of the septic tanks and groundwater quality in study area is suggested along with remedial measures.

Determination of essential and toxic elements in clay soil commonly consumed by pregnant women in Tanzania

NASA Astrophysics Data System (ADS)

Mwalongo, D.; Mohammed, N. K.

2013-10-01

A habit of eating clay soil especially among pregnant women is a common practice in Tanzania. This practice known as geophagy might introduce toxic elements in the consumer's body to endanger the health of the mother and her child. Therefore it is very important to have information on the elemental composition of the eaten soil so as to assess the safety nature of the habit. In this study 100 samples of clay soil, which were reported to be originating from five regions in Tanzania and are consumed by pregnant women were analyzed to determine their levels of essential and toxic elements. The analysis was carried out using energy dispersive X-ray fluorescent technique (EDXRF) of Tanzania Atomic Energy Commission, Arusha. Essential elements Fe, Zn, Cu, Se and Mn and toxic elements As, Pb, Co, Ni, U and Th were detected in concentrations above WHO permissible limits in some of the samples. The results from this study show that the habit of eating soil is exposing the pregnant mothers and their children to metal toxicity which is detrimental to their health. Hence, further actions should be taken to discourage the habit of eating soil at all levels.

A study on toxic and essential elements in wheat grain from the Republic of Kazakhstan.

PubMed

Tattibayeva, Damira; Nebot, Carolina; Miranda, Jose M; Abuova, Altynai B; Baibatyrov, Torebek A; Kizatova, Maigul Z; Cepeda, Alberto; Franco, Carlos M

2016-03-01

Little information is currently available about the content of different elements in wheat samples from the Republic of Kazakhstan. The concentrations of toxic (As, Cd, Cr, Hg, Pb, and U) and essential (Co, Cu, Fe, Mn, Ni, Se, and Zn) elements in 117 sampled wheat grains from the Republic of Kazakhstan were measured. The results indicated that the mean and maximum concentrations of most investigated elements (As, Cd, Co, Cr, Mn, Se, Pb, and U) were higher in samples collected from southern Kazakhstan. The mean and maximum concentrations of toxic elements such as As, Cd, Hg, and Pb did not exceed levels specified by European, FAO, or Kazakh legislation, although the hazard quotient (HQ) values for Co, Cu, Mn, and Zn were higher than 1 and the hazard index (HI) was higher than 1 for samples collected from all areas of Kazakhstan. This indicates that there should be concern about the potential hazards of the combination of toxic elements in Kazakh wheat.

Metal accumulation screening of the Río Tinto flora (Huelva, Spain).

PubMed

de la Fuente, Vicenta; Rufo, Lourdes; Rodríguez, Nuria; Amils, Ricardo; Zuluaga, Javier

2010-06-01

Río Tinto (Huelva, Spain) is located in one of the most important mining regions in the world. Its soils are characterized by their extreme acidity and elevated concentrations of heavy metals. Due to these characteristics, the Tinto ecosystem is considered unique and an ideal location to study biological adaptations to this type of habitat. Plant species that present these adaptations might be useful to mining and other metal pollution restoration programs. This study reports the results for the screening of Ca, Mg, Na, Mn, Fe, Ni, Cu, Zn, As, and Pb in aerial tissues of 97 plant species from the Tinto basin flora. In addition, plant-soil relationships were analyzed using the biological absorption coefficient (BAC) to detect the main plant adaptations in the Tinto flora. The species selected are representative of the biomass of the main dominant edaphophile and climatophile vegetation communities of the three river sections, forest, and subseral stages. Plant and soil elemental analyses were performed using inductively coupled plasma-mass spectrometry technique (ICP-MS). The results indicate that in general, Tinto flora shows a pattern of accumulation of the analyzed elements in aerial tissues which agrees with the nutritional requirements of vascular plants (macronutrients > micronutrients > indifferent or toxic elements). Among macronutrients, Ca seems to be an essential element in this habitat. This element accumulates in the aerial plant tissues. Basically, the Río Tinto flora is made of Fe, Cu, Zn, Ni, As, and Pb excluders, although some analyzed species of Erica, Quercus, Lavandula, Cistus, Genista, and Cytisus genera can be considered Mn accumulators. The results of this study make up a body of fundamental knowledge of the strategies used by plants to thrive in habitats with high concentrations of toxic heavy metals. This information is vital when it comes to planning a restoration program. Plants must be selected and used according to the requirements, always respecting the characteristics of the territory and facilitating the development of suitable vegetation.

Influence of Selected Organic Micropollutants on Organisms

NASA Astrophysics Data System (ADS)

Włodarczyk-Makuła, Maria

2017-03-01

This article describes the toxicity of organic micropollutants on tested microorganisms. Itis a current issue because organic micropollutants are identified in all elements of environmental (surface water, ground water, soils) and in food products. The organic micropollutants include: polychlorinated dibenzodioxyns PCDD, polychlorinated dibenzofurans PCDF, polychlorinated biphenyls PCB, polycyclic aromatic hydrocarbons PAH, halogenated compounds and by-products of water treatment. Some organic compounds cause hazard for health and human life due to their estrogenic biological activity, carcinogenic, mutagenic or teratogenic activity. The influence on organisms indicators of these compounds based on literature data were presented. The level of TEQ (toxic equivalency) in response to organic chlorine derivatives (PCDDs, PCDF, PCBs) is usually determined by toxic equivalency factor (TEF). The International Agency for Research on Cancer classifies organic micropollutants as carcinogenic to humans (Group 1), possibly carcinogenic (Group 2A) or probably carcinogenic to humans (Group 2B).

Toxic and trace elements in tobacco and tobacco smoke.

PubMed Central

Chiba, M.; Masironi, R.

1992-01-01

While the harmful health effects of carbon monoxide, nicotine, tar, irritants and other noxious gases that are present in tobacco smoke are well known, those due to heavy metals and other toxic mineral elements in tobacco smoke are not sufficiently emphasized. Tobacco smoking influences the concentrations of several elements in some organs. This review summarizes the known effects of some trace elements and other biochemically important elements (Al, As, Cd, Cr, Cu, Pb, Mn, Hg, Ni, Po-210, Se, and Zn) which are linked with smoking. Cigarette smoking may be a substantial source of intake of these hazardous elements not only to the smoker but also, through passive smoking, to nonsmokers. The adverse health effects of these toxic elements on the fetus through maternal smoking, and on infants through parental smoking, are of special concern. PMID:1600587

Toxicological Assessment of Toxic Element Residues in Swine Kidney and Its Role in Public Health Risk Assessment

PubMed Central

Milićević, Dragan R.; Jovanović, Milijan; Jurić, Verica B.; Petrović, Zoran I.; Stefanović, Srđan M.

2009-01-01

In order to ensure the safety of consumers in Serbia the prevalence of toxic elements (As, Cd, Hg, Pb) in swine kidney collected from three different areas in Serbia (n = 90) was determined by atomic absorption spectrometry. Also, in order to find information on the effects of accumulation of toxic elements on swine kidney, pathohistological examination of the kidneys was performed. The presence of mercury was found in 33.3% of kidney samples in the range of 0.005–0.055 mg/kg, while the presence of cadmium was detected less often (27.7%) but in larger amounts (0.05–1.23 mg/kg). The presence of arsenic was found only in one sample, while no lead was found. The results of the metal-to-metal correlation analysis supported there were the result of different sources of contamination. Pathohistological examination of kidneys confirms tubulopathies with oedema and cell vacuolization. In addition, haemorrhages and necrosis of proximal kidney tubule cells were found. This study demonstrates that toxic elements in Serbian slaughtered pigs are found at levels comparable to those reported in other countries, and consequently the levels reported in this study do not represent a concern from a consumer safety point of view. The lack of a strong correlation between histopathological changes and the incidence of toxic elements found in this study might be explained as the result of synergism among toxic elements and other nephrotoxic compounds which enhance the toxicity of the individual toxins even at the relatively low mean concentrations observed in this study. PMID:20049251

Toxic trace elements at gastrointestinal level.

PubMed

Vázquez, M; Calatayud, M; Jadán Piedra, C; Chiocchetti, G M; Vélez, D; Devesa, V

2015-12-01

Many trace elements are considered essential [iron (Fe), zinc (Zn), copper (Cu)], whereas others may be harmful [lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As)], depending on their concentration and chemical form. In most cases, the diet is the main pathway by which they enter our organism. The presence of toxic trace elements in food has been known for a long time, and many of the food matrices that carry them have been identified. This has led to the appearance of legislation and recommendations concerning consumption. Given that the main route of exposure is oral, passage through the gastrointestinal tract plays a fundamental role in their entry into the organism, where they exert their toxic effect. Although the digestive system can be considered to be of crucial importance in their toxicity, in most cases we do not know the events that occur during the passage of these elements through the gastrointestinal tract and of ascertaining whether they may have some kind of toxic effect on it. The aim of this review is to summarize available information on this subject, concentrating on the toxic trace elements that are of greatest interest for organizations concerned with food safety and health: Pb, Cd, Hg and As. Copyright © 2015 Elsevier Ltd. All rights reserved.

Toxic Element Contamination of Natural Health Products and Pharmaceutical Preparations

PubMed Central

Genuis, Stephen J.; Schwalfenberg, Gerry; Siy, Anna-Kristen J.; Rodushkin, Ilya

2012-01-01

Background Concern has recently emerged regarding the safety of natural health products (NHPs)–therapies that are increasingly recommended by various health providers, including conventional physicians. Recognizing that most individuals in the Western world now consume vitamins and many take herbal agents, this study endeavored to determine levels of toxic element contamination within a range of NHPs. Methods Toxic element testing was performed on 121 NHPs (including Ayurvedic, traditional Chinese, and various marine-source products) as well as 49 routinely prescribed pharmaceutical preparations. Testing was also performed on several batches of one prenatal supplement, with multiple samples tested within each batch. Results were compared to existing toxicant regulatory limits. Results Toxic element contamination was found in many supplements and pharmaceuticals; levels exceeding established limits were only found in a small percentage of the NHPs tested and none of the drugs tested. Some NHPs demonstrated contamination levels above preferred daily endpoints for mercury, cadmium, lead, arsenic or aluminum. NHPs manufactured in China generally had higher levels of mercury and aluminum. Conclusions Exposure to toxic elements is occurring regularly as a result of some contaminated NHPs. Best practices for quality control–developed and implemented by the NHP industry with government oversight–is recommended to guard the safety of unsuspecting consumers. PMID:23185404

Occurrence and mobility of toxic elements in coals from endemic fluorosis areas in the Three Gorges Region, SW China.

PubMed

Xiong, Yan; Xiao, Tangfu; Liu, Yizhang; Zhu, Jianming; Ning, Zengping; Xiao, Qingxiang

2017-10-01

Fluorine (F) is a topic of great interest in coal-combustion related endemic fluorosis areas. However, little extent research exists regarding the environmental geochemistry of toxic elements that are enriched in coals and coal wastes in traditional endemic fluorosis areas, particularly focusing on their occurrences and mobilities during the weathering-leaching processes of coals and coal wastes in the surface environment. This paper addressed the issue of toxic elements in coals and coal wastes in the Three Gorges Region, Southwest (SW) China, where endemic fluorosis has historically prevailed, and investigated the distribution, occurrence, mobility features, and associated potential health risks. For this purpose, a modified experiment combined with long-term humidity cell test and column leaching trial was applied to elucidate the mobility of toxic elements in coals and coal wastes. In addition, sequential chemical extraction (SCE) was used to ascertain the modes of occurrence of toxic elements. The results demonstrated that the contents of toxic elements in the study area followed the order: stone coals > gangues > coal balls > coals. Furthermore, modes of occurrence of toxic elements were obviously different in coals and coal wastes. For example, cadmium (Cd) was mainly associated with monosulfide fraction in coals, molybdenum (Mo) and arsenic (As) were mainly associated with carbonate and silicate in coal gangues and stone coals, chromium (Cr) mainly existed in silicate and insoluble matter in coal gangues and coal balls, thallium (Tl) mainly occurred in organic matter in stone coals and sulfide in coals, and the occurrence of antimony (Sb) varied with different kinds of samples. Moreover, a large amount of toxic elements released to the leachates during the weathering and leaching process, which might pollute the environment and threaten human health. Based on the geo-accumulation index (I geo ), single factor index (P i ) and Nemerow index (P N ), soils i n the study area were mainly polluted by Cd, which constituted a potential risk to locally planted crops. Copyright © 2017 Elsevier Inc. All rights reserved.

Biochar application to hardrock mine tailings: Soil quality, microbial activity, and toxic element sorption

USGS Publications Warehouse

Kelly, Charlene N.; Peltz, Christopher D.; Stanton, Mark R.; Rutherford, David W.; Rostad, Colleen E.

2014-01-01

Waste rock piles from historic mining activities remain unvegetated as a result of metal toxicity and high acidity. Biochar has been proposed as a low-cost remediation strategy to increase soil pH and reduce leaching of toxic elements, and improve plant establishment. In this laboratory column study, biochar made from beetle-killed pine wood was assessed for utility as a soil amendment by mixing soil material from two mine sites collected near Silverton, Colorado, USA with four application rates of biochar (0%, 10%, 20%, 30% vol:vol). Columns were leached seven times over 65 days and leachate pH and concentration of toxic elements and base cations were measured at each leaching. Nutrient availability and soil physical and biological parameters were determined following the incubation period. We investigated the hypotheses that biochar incorporation into acidic mine materials will (1) reduce toxic element concentrations in leaching solution, (2) improve soil parameters (i.e. increase nutrient and water holding capacity and pH, and decrease compaction), and (3) increase microbial populations and activity. Biochar directly increased soil pH (from 3.33 to 3.63 and from 4.07 to 4.77 in the two materials) and organic matter content, and decreased bulk density and extractable salt content in both mine materials, and increased nitrate availability in one material. No changes in microbial population or activity were detected in either mine material upon biochar application. In leachate solution, biochar increased base cations from both materials and reduced the concentrations of Al, Cd, Cu, Pb, and Zn in leachate solution from one material. However, in the material with greater toxic element content, biochar did not reduce concentrations of any measured dissolved toxic elements in leachate and resulted in a potentially detrimental release of Cd and Zn into solution at concentrations above that of the pure mine material. The length of time of effectiveness and specific sorption by biochar is variable by element and the toxic element concentration and acidity of the initial mine material.

Concentrations of cadmium and selected essential elements in malignant large intestine tissue

PubMed Central

Dziki, Adam; Kilanowicz, Anna; Sapota, Andrzej; Duda-Szymańska, Joanna; Daragó, Adam

2015-01-01

Introduction Colorectal cancer is one of the most common cancers worldwide. Incidence rates of large intestine cancer indicate a role of environmental and occupational factors. The role of essential elements and their interaction with toxic metals can contribute to the explanation of a complex mechanism by which large intestine cancer develops. Bearing this in mind, determining the levels of essential and toxic elements in tissues (organs), as well as in body fluids, seems to shed light on their role in the mode of action in malignant disease. Aim Determination of the levels of cadmium, zinc, copper, selenium, calcium, magnesium, and iron in large intestine malignant tissue. Material and methods Two intraoperative intestine sections were investigated: one from the malignant tissue and the other one from the normal tissue, collected from each person with diagnosed large intestine cancer. Cadmium, zinc, copper, calcium, magnesium, and iron levels were determined with atomic absorption spectrometry, and selenium levels by spectrofluorimetric method. Results The levels of copper, selenium, and magnesium were higher in the malignant than in normal tissues. In addition, the zinc/copper and calcium/magnesium relationship was altered in malignant tissue, where correlations were lower compared to non-malignant tissue. Conclusions The results seems to demonstrate disturbed homeostasis of some essential elements. However, it is hard to confirm their involvement in the aetiology of colorectal cancer. PMID:27110307

Laser ablation ICP-MS profiling and semiquantitative determination of trace element concentrations in desert tortoise shells: documenting the uptake of elemental toxicants.

PubMed

Seltzer, Michaeld; Berry, Kristinh

2005-03-01

The outer keratin layer (scute) of desert tortoise shells consists of incrementally grown laminae in which various bioaccumulated trace elements are sequestered during scute deposition. Laser ablation ICP-MS examination of laminae in scutes of dead tortoises revealed patterns of trace elemental distribution from which the chronology of elemental uptake can be inferred. These patterns may be of pathologic significance in the case of elemental toxicants such as arsenic, which has been linked to both shell and respiratory diseases. Laser ablation transects, performed along the lateral surfaces of sectioned scutes, offered the most successful means of avoiding exogenous contamination that was present on the scute exterior. Semiquantitative determination of elemental concentrations was achieved using sulfur, a keratin matrix element, as an internal standard. The results presented here highlight the potential of laser ablation ICP-MS as a diagnostic tool for investigating toxic element uptake as it pertains to tortoise morbidity and mortality.

Laser ablation ICP-MS profiling and semiquantitative determination of trace element concentrations in desert tortoise shells: Documenting the uptake of elemental toxicants

USGS Publications Warehouse

Seltzer, M.D.; Berry, K.H.

2005-01-01

The outer keratin layer (scute) of desert tortoise shells consists of incrementally grown laminae in which various bioaccumulated trace elements are sequestered during scute deposition. Laser ablation ICP-MS examination of laminae in scutes of dead tortoises revealed patterns of trace elemental distribution from which the chronology of elemental uptake can be inferred. These patterns may be of pathologic significance in the case of elemental toxicants such as arsenic, which has been linked to both shell and respiratory diseases. Laser ablation transects, performed along the lateral surfaces of sectioned scutes, offered the most successful means of avoiding exogenous contamination that was present on the scute exterior. Semiquantitative determination of elemental concentrations was achieved using sulfur, a keratin matrix element, as an internal standard. The results presented here highlight the potential of laser ablation ICP-MS as a diagnostic tool for investigating toxic element uptake as it pertains to tortoise morbidity and mortality.

Acute and chronic systemic chromium toxicity.

PubMed

Gad, S C

1989-10-01

Although chromium and compounds containing it have been recognized as having potential severe adverse effects on health for more than 160 years, understanding of the systemic toxicology and true hazard of these compounds is still not complete. A review of the current state of knowledge is attempted in this paper, with appropriate attention given to the complications of multiple valence states and solubility. Selected chromium compounds, particularly hexavalent ones, are carcinogens, corrosives, delayed contact sensitizers, and have the kidney as their primary target organ. But chromium is also an essential element for humans. The body clearly possesses some effective detoxification mechanisms for some degree of exposure to hexavalent chrome compounds. The significant features of acute and chronic chromium toxicity are presented in view of these considerations.

Selenium, selected inorganic elements, and organochlorine pesticides in bottom material and biota from the Colorado River delta

USGS Publications Warehouse

Garcia-Hernandez, J.; King, K.A.; Velasco, A.L.; Shumilin, E.; Mora, M.A.; Glenn, E.P.

2001-01-01

Concentrations of selenium (Se) in bottom material ranged from 0.6 to 5.0 μg g−1, and from 0.5 to 18.3 μg g−1in biota; 23% of samples exceeded the toxic threshold. Concentrations of DDE in biota exceeded the toxic threshold in 30% of the samples. Greater concentrations of selenium in biota were found at sites with strongly reducing conditions, no output, alternating periods of drying and flooding or dredging activities, and at sites that received water directly from the Colorado River. The smallest Se concentrations in biota were found at sites where an outflow and exposure or physical disturbance of the bottom material were uncommon.

Phytoremediation of soils contaminated with toxic elements and radionuclides

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

Cornish, J.E.; Goldberg, W.C.; Levine, R.S.

1995-12-31

At many US Department of Energy (US DOE) facilities and other sites, surface soils over relatively large areas are contaminated with heavy metals, radionuclides, and other toxic elements, often at only a relatively small factor above regulatory action levels. Cleanup of such sites presents major challenges, because currently available soil remediation technologies can be very expensive. In response, the US DOE`s Office of Technology Development, through the Western Environmental Technology Office, is sponsoring research in the area of phytoremediation. Phytoremediation is an emerging technology that uses higher plants to transfer toxic elements and radionuclides from surface soils into aboveground biomass.more » Some plants, termed hyperaccumulators, take up toxic elements in substantial amounts, resulting in concentrations in aboveground biomass over 100 times those observed with conventional plants. After growth, the plant biomass is harvested, and the toxic elements are concentrated and reclaimed or disposed of. As growing, harvesting, and processing plant biomass is relatively inexpensive, phytoremediation can be a low-cost technology for remediation of extensive areas having lightly to moderately contaminated soils. This paper reviews the potential of hyper- and moderate accumulator plants in soil remediation, provides some comparative cost estimates, and outlines ongoing work initiated by the US DOE.« less

Environmental biomonitoring of essential and toxic elements in human scalp hair using accelerated microwave-assisted sample digestion and inductively coupled plasma optical emission spectroscopy.

PubMed

Kumakli, Hope; Duncan, A'ja V; McDaniel, Kiara; Mehari, Tsdale F; Stephenson, Jamira; Maple, Lareisha; Crawford, Zaria; Macemore, Calvin L; Babyak, Carol M; Fakayode, Sayo O

2017-05-01

Human scalp hair samples were collected and used to assess exposure to toxic elements and essential elements in the state of North Carolina, USA using accelerated microwave assisted acid digestion and inductively coupled plasma optical emission spectroscopy (ICP-OES). The figures-of-merit of the ICP-OES were appropriate for elemental analysis in scalp hair with detection limits as low as 0.0001 mg/L for Cd, good linearity (R 2  > 0.9978), and percent recoveries that ranged from 96 to 106% for laboratory-fortified-blanks and 88-112% for sample spike recovery study. The concentrations of essential elements in scalp hair were larger than those of toxic elements, with Ca having the highest average concentration (3080 μg/g, s = 14,500, n = 194). Some of the maximum concentrations observed for As (65 μg/g), Ni (331 μg/g), Cd (2.96 μg/g), and Cr (84.6 μg/g) in individual samples were concerning, however. Samples were statistically analyzed to determine the influence of race, gender, smoking habits, or age on the elemental concentrations in scalp hair. Higher concentrations of essential elements were observed in the scalp hair of Caucasians, females, and non-smokers, and the differences were often significant at a 90% confidence level. Several pairs of essential elements, for example Ca-K, Ca-Mg, and Ca-Zn, were strongly correlated in Caucasian hair but uncorrelated in African-American hair. Similarly, essential elements were strongly correlated in female hair but weakly correlated in male hair. Toxic element pairs (As-Cd, As-Se, Pb-As, and Se-Cd) were strongly correlated in the hair of smokers but uncorrelated in that of non-smokers, suggesting that cigarette smoke is a common source of toxic elements in humans. Published by Elsevier Ltd.

Study of the Accumulation of Toxic and Essential Ultra-Trace Elements in Fruits of Sorbus domestica L.

PubMed Central

Zeiner, Michaela; Juranović Cindrić, Iva; Majić, Boris; Stingeder, Gerhard

2017-01-01

In the present work, the accumulation of selected toxic and essential ultra-trace elements in fruits of service tree (Sorbus domestica L.) were determined depending on harvest time. Samples were collected from the same sampling area in two different years and within one year in September and October (maturity state). Harvesting the fruits in the same area excludes the influence of metals taken up via roots, thus the impact of airborne contamination by heavy metal translocation can be studied. All samples were dried and digested using an acidic microwave assisted digestion system prior to quantification by inductively coupled plasma—sector field mass spectrometry (ICP–SFMS). The elements chosen were Arsenic and Cadmium as well as Lithium, Molybdenum, and Selenium. The Arsenic content rose with maturity in mesocarp. Cadmium found in the mesocarp was unaffected by ripeness. For Selenium and Molybdenum, no statistically significant effect of ripeness could be found on their content in mesocarp. Lithium could not be detected in the majority of fruit samples. Differences between the metal concentrations based on the year of harvest were found for Arsenic, Molybdenum, and Selenium, depending on precipitation. The drier the season, the more Arsenic was accumulated. For Molybdenum and Selenium, the opposite effect was observed. PMID:28338629

Study of the Accumulation of Toxic and Essential Ultra-Trace Elements in Fruits of Sorbus domestica L.

PubMed

Zeiner, Michaela; Juranović Cindrić, Iva; Majić, Boris; Stingeder, Gerhard

2017-03-24

In the present work, the accumulation of selected toxic and essential ultra-trace elements in fruits of service tree ( Sorbus domestica L.) were determined depending on harvest time. Samples were collected from the same sampling area in two different years and within one year in September and October (maturity state). Harvesting the fruits in the same area excludes the influence of metals taken up via roots, thus the impact of airborne contamination by heavy metal translocation can be studied. All samples were dried and digested using an acidic microwave assisted digestion system prior to quantification by inductively coupled plasma-sector field mass spectrometry (ICP-SFMS). The elements chosen were Arsenic and Cadmium as well as Lithium, Molybdenum, and Selenium. The Arsenic content rose with maturity in mesocarp. Cadmium found in the mesocarp was unaffected by ripeness. For Selenium and Molybdenum, no statistically significant effect of ripeness could be found on their content in mesocarp. Lithium could not be detected in the majority of fruit samples. Differences between the metal concentrations based on the year of harvest were found for Arsenic, Molybdenum, and Selenium, depending on precipitation. The drier the season, the more Arsenic was accumulated. For Molybdenum and Selenium, the opposite effect was observed.

Guidelines for performing systematic reviews in the development of toxicity factors.

PubMed

Schaefer, Heather R; Myers, Jessica L

2017-12-01

The Texas Commission on Environmental Quality (TCEQ) developed guidance on conducting systematic reviews during the development of chemical-specific toxicity factors. Using elements from publicly available frameworks, the TCEQ systematic review process was developed in order to supplement the existing TCEQ Guidelines for developing toxicity factors (TCEQ Regulatory Guidance 442). The TCEQ systematic review process includes six steps: 1) Problem Formulation; 2) Systematic Literature Review and Study Selection; 3) Data Extraction; 4) Study Quality and Risk of Bias Assessment; 5) Evidence Integration and Endpoint Determination; and 6) Confidence Rating. This document provides guidance on conducting a systematic literature review and integrating evidence from different data streams when developing chemical-specific reference values (ReVs) and unit risk factors (URFs). However, this process can also be modified or expanded to address other questions that would benefit from systematic review practices. The systematic review and evidence integration framework can improve regulatory decision-making processes, increase transparency, minimize bias, improve consistency between different risk assessments, and further improve confidence in toxicity factor development. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

The impact of human activities in soils and sediments on urban and peri-urban areas

NASA Astrophysics Data System (ADS)

Horváth, Adrienn; Szita, Renáta; Bidló, András; Gribovszki, Zoltán

2017-04-01

In this current research we would like to detect the amount of the differences between the natural, the suburb and the urban areas. The aim of the investigation was to determine the impact of human activities on urban and peri-urban soils of Sopron. 72 urban soil samples were collected on 6 sub-catchments for analysing the background pollution of Rák Creek in Sopron. After the analysis of chemical and physical properties of urban soil samples, two element fractions - the total (HNO3+H2O2-extractable) and the available NH4-acetate+EDTA-extractable - were used for element determination. Toxic elements were measured by ICP-OES in the urban soils and the sediments as well. in case of sediment samples from thalweg and dead region. That were collected from the bank of the Rák creek at 6 sampling points to calculate enrichment factors to assess the possible harmful effects of toxic metals. The field and laboratory data were processed using a GIS softver DigiTerraMap. Six elements were selected for analyses Co, Cd, Ni, Cu, Zn, Pb, which are prominent in urban soils. Statistical analysis was carried out with Microsoft Office Excel 2003, STATISTICA 11 and R Studio. C2 program was used for the distribution of toxic elements. Based on results e.g. pH, etc., there were definite differences between natural HAZ, BAN, semi-natural HAJNAL and urbanized FASOR, GYORI, TESCO areas and significant differences in toxic element distribution as well. The toxic elements of sediment showed the following tendency: Pb > Zn > Cu > Ni = Co. The Co and the Ni values were lower than the natural background limits. The Cutotal exceeded the first interventional pollution limit > 75 mg.kg-1 and the available Zn and Pb were higher than the suggested interventional pollution limits Znavailable >40 mg.kg-1; Pbavailable >25 mg.kg-1 at GYORI sub-catchment. The EF values were generally higher in dead region than in thalweg except of GYORI point. Lead had the highest EF values between the five metals investigated and it is followed by Zn strongly. The EFPb > 5, which indicates the moderate degree of Pb contamination inside the town. Co, Cu and Ni exhibited the lowest in our EF values. Summarized, the largest heavy metal values were in sampling point GYORI. The EF values for Pb and Zn increased towards city. The accumulation of Pb was confirmed by moderate enrichment of sediment samples, which are originated from the busiest transport hub of Sopron. The difference between natural and urban areas seemed definite based on our results. Even though the flow characteristic of the dead region and thalweg of the natural part of the stream was different, the heavy metals accumulated in the dead region mainly in the urbanized area.

Toxic Elements in Different Medicinal Plants and the Impact on Human Health.

PubMed

Brima, Eid I

2017-10-11

Local medicinal plants from Madina, Saudi Arabia, are used to cure various diseases. However, some can cause adverse health effects. Five different medicinal plants were collected in the city of Madina: mahareeb ( Cymbopogon ), sheeh ( Artemisia ), harjal ( Cynanchum argel delile ), nabipoot ( Equisetum ), and kafmariam ( Vitex agnus-castus ). In total, four toxic elements including Al, Pb, As, and Cd were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The range of recoveries fell between 86.1 and 90.6% for all measured elements. Al levels were the highest of any of the studied elements in all plant samples, with Cymbopogon showing the highest levels. The range of concentrations of Al was 156-1609 mg/kg. Cd appeared at the lowest levels in all plants samples, with Vitex agnus-castus containing this element at the highest levels. Cd concentrations were in the range of 0.01-0.10 mg/kg. A washing process lowered the toxic elements in all plants; average % recoveries were Al (47.32%), As (59.1%), Cd (62.03%), and Pb (32.40%). The calculated human health risk assessment in one dose for toxic elements in all plants was as follows: Al (1.33 × 10 -3 -5.57 × 10 -2 mg/kg.bw), Pb (0-8.86 × 10 -5 mg/kg.bw), As (3.43 × 10 -7 -1.33 × 10 -5 mg/kg.bw), and Cd (0-3.14 × 10 -6 mg/kg.bw). Medicinal plants are a source of exposure to toxic elements. However, none of the plants in this study exceeded the daily guideline set by the WHO for any element based on conventional use by the local population. We may cautiously conclude that these medicinal plants pose no risk to users based on conventional use.

Experimental substantiation of the possibility of developing selenium- and iodine-containing pharmaceuticals based on blue-green algae Spirulina platensis.

PubMed

Mosulishvili, L M; Kirkesali, E I; Belokobylsky, A I; Khizanishvili, A I; Frontasyeva, M V; Pavlov, S S; Gundorina, S F

2002-08-22

The great potential of using blue-green algae Spirulina platensis as a matrix for the production of selenium- and iodine-containing pharmaceuticals is shown experimentally. The background levels of 31 major, minor and trace elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni (using (n,p) reaction), As, Br, Zn, Rb, Mo, Ag, Sb, I, Ba, Sm, Tb, Tm, Hf, Ta, W, Au, Hg, Th) in S. platensis biomass were determined by means of epithermal neutron activation analysis. The dependence of selenium and iodine accumulation in spirulina biomass on a nutrient medium loading of the above elements was characterized. To demonstrate the possibilities of determining toxic element intake by spirulina biomass, mercury was selected. The technological parameters for production of iodinated treatment-and-prophylactic pills are developed.

Speciation in Metal Toxicity and Metal-Based Therapeutics

PubMed Central

Templeton, Douglas M.

2015-01-01

Metallic elements, ions and compounds produce varying degrees of toxicity in organisms with which they come into contact. Metal speciation is critical to understanding these adverse effects; the adjectives “heavy” and “toxic” are not helpful in describing the biological properties of individual elements, but detailed chemical structures are. As a broad generalization, the metallic form of an element is inert, and the ionic salts are the species that show more significant bioavailability. Yet the salts and other chelates of a metal ion can give rise to quite different toxicities, as exemplified by a range of carcinogenic potential for various nickel species. Another important distinction comes when a metallic element is organified, increasing its lipophilicity and hence its ability to penetrate the blood brain barrier, as is seen, for example, with organic mercury and tin species. Some metallic elements, such as gold and platinum, are themselves useful therapeutic agents in some forms, while other species of the same element can be toxic, thus focusing attention on species interconversions in evaluating metal-based drugs. The therapeutic use of metal-chelating agents introduces new species of the target metal in vivo, and this can affect not only its desired detoxification, but also introduce a potential for further mechanisms of toxicity. Examples of therapeutic iron chelator species are discussed in this context, as well as the more recent aspects of development of chelation therapy for uranium exposure. PMID:29056656

Occurrence and risk assessment of potentially toxic elements and typical organic pollutants in contaminated rural soils.

PubMed

Xu, Yongfeng; Dai, Shixiang; Meng, Ke; Wang, Yuting; Ren, Wenjie; Zhao, Ling; Christie, Peter; Teng, Ying

2018-07-15

The residual levels and risk assessment of several potentially toxic elements (PTEs), phthalate esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs) in rural soils near different types of pollution sources in Tianjin, China, were studied. The soils were found to be polluted to different extents with PTEs, PAEs and PAHs from different pollution sources. The soil concentrations of chromium (Cr), nickel (Ni), di-n-butyl phthalate (DnBP), acenaphthylene (Any) and acenaphthene (Ane) were higher than their corresponding regulatory reference limits. The health risk assessment model used to calculate human exposure indicates that both non-carcinogenic and carcinogenic risks from selected pollutants were generally acceptable or close to acceptable. Different types of pollution sources and soil physicochemical properties substantially affected the soil residual concentrations of and risks from these pollutants. PTEs in soils collected from agricultural lands around industrial and residential areas and organic pollutants (PAEs and PAHs) in soils collected from agricultural areas around livestock breeding were higher than those from other types of pollution sources and merit long-term monitoring. Copyright © 2018 Elsevier B.V. All rights reserved.

Trace elements in blood samples of smoker and nonsmoker active pulmonary tuberculosis patients from Jamshoro, Pakistan.

PubMed

Memon, Zainab Manzoor; Yilmaz, Erkan; Shah, Afsheen Mushtaque; Sahin, Ugur; Kazi, Tasneem Gul; Devrajani, Bikha Ram; Soylak, Mustafa

2017-12-01

Pulmonary tuberculosis (PTB) is a serious public threat throughout the world. PTB and smoking have a strong correlation. Malnutrition, poverty, addiction, overcrowding, illiteracy, unemployment, and poor hygienic conditions are the collective aspects for the disease progress. Pakistan is the fifth among 22 high tuberculosis (TB) burden countries and the fourth regarding multidrug-resistant tuberculosis (MDR-TB). The aim of study was to determine the concentration of essential and toxic elements from blood samples of smoker and nonsmoker PTB patients by inductively coupled plasma mass spectrometry (ICP-MS) followed by microwave acid digestion and compared with control subjects (n = 30). Eighty PTB patients were selected from different hospitals with age ranging 20-70 years. It was interpreted that the mean age among males and females was found to be 35.6 ± 1.4 and 33.5 ± 1.2, respectively, and the male patients were highly affected in contrast to females. Essential elements such as Mn, Fe, Zn, and Se were statistically found to be lower while Ca, Co, and Cu were found to be higher compared to the control group (p = 0.00). However, toxic elements like Al, Cr, Ni, As, Cd, and Pb were statistically elevated in smokers than nonsmokers. Further research is needed to understand the degree of the impact of essential trace elements on treatment outcome (follow-up) followed by balanced healthy nutritional supplementation along with medical therapy, consequently improving the pulmonary tuberculosis outcome and survival as well.

A simple scheme to determine potential aquatic metal toxicity from mining wastes

USGS Publications Warehouse

Wildeman, T.R.; Smith, K.S.; Ranville, J.F.

2007-01-01

A decision tree (mining waste decision tree) that uses simple physical and chemical tests has been developed to determine whether effluent from mine waste material poses a potential toxicity threat to the aquatic environment. For the chemical portion of the tree, leaching tests developed by the United States Geological Survey, the Colorado Division of Minerals and Geology (Denver, CO), and a modified 1311 toxicity characteristic leaching procedure (TCLP) test of the United States Environmental Protection Agency have been extensively used as a surrogate for readily available metals that can be released into the environment from mining wastes. To assist in the assessment, element concentration pattern graphs (ECPG) are produced that compare concentrations of selected groups of elements from the three leachates and any water associated with the mining waste. The MWDT makes a distinction between leachates or waters with pH less than or greater than 5. Generally, when the pH values are below 5, the ECPG of the solutions are quite similar, and potential aquatic toxicity from cationic metals, such as Pb, Cu, Zn, Cd, and Al, is assumed. Below pH 5, these metals are mostly dissolved, generally are not complexed with organic or inorganic ligands, and hence are more bioavailable. Furthermore, there is virtually no carbonate alkalinity at pH less than 5. All of these factors promote metal toxicity to aquatic organisms. On the other hand, when the pH value of the water or the leachates is above 5, the ECPG from the solutions are variable, and inferred aquatic toxicity depends on factors in addition to the metals released from the leaching tests. Hence, leachates and waters with pH above 5 warrant further examination of their chemical composition. Physical ranking criteria provide additional information, particularly in areas where waste piles exhibit similar chemical rankings. Rankings from physical and chemical criteria generally are not correlated. Examples of how this decision tree has been applied in assessing mine sites are discussed. Copyright ?? Taylor & Francis Group, LLC.

A novel microbial fuel cell sensor with biocathode sensing element.

PubMed

Jiang, Yong; Liang, Peng; Liu, Panpan; Wang, Donglin; Miao, Bo; Huang, Xia

2017-08-15

The traditional microbial fuel cell (MFC) sensor with bioanode as sensing element delivers limited sensitivity to toxicity monitoring, restricted application to only anaerobic and organic rich water body, and increased potential fault warning to the combined shock of organic matter/toxicity. In this study, the biocathode for oxygen reduction reaction was employed for the first time as the sensing element in MFC sensor for toxicity monitoring. The results shown that the sensitivity of MFC sensor with biocathode sensing element (7.4±2.0 to 67.5±4.0mA% -1 cm -2 ) was much greater than that showed by bioanode sensing element (3.4±1.5 to 5.5±0.7mA% -1 cm -2 ). The biocathode sensing element achieved the lowest detection limit reported to date using MFC sensor for formaldehyde detection (0.0005%), while the bioanode was more applicable for higher concentration (>0.0025%). There was a quicker response of biocathode sensing element with the increase of conductivity and dissolved oxygen (DO). The biocathode sensing element made the MFC sensor directly applied to clean water body monitoring, e.g., drinking water and reclaimed water, without the amending of background organic matter, and it also decreased the warning failure when challenged by a combined shock of organic matter/toxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

Jointed toxicity of TiO2 NPs and Cd to rice seedlings: NPs alleviated Cd toxicity and Cd promoted NPs uptake.

PubMed

Ji, Ye; Zhou, Yun; Ma, Chuanxin; Feng, Yan; Hao, Yi; Rui, Yukui; Wu, Wenhao; Gui, Xin; Le, Van Nhan; Han, Yaning; Wang, Yingcai; Xing, Baoshan; Liu, Liming; Cao, Weidong

2017-01-01

Previous studies have reported that nanoparticles (NPs) and heavy metals are toxic to the environment. However, the jointed toxicity is not yet well understood. This study was aimed to investigate the combined toxicity of TiO 2 NPs and the heavy metal cadmium (Cd) to plants. Rice (Oryzasativa L.) was selected as the target plant. The rice seedlings were randomly separated into 12 groups and treated with CdCl 2 (0, 10 and 20 mg/L) and TiO 2 NPs (0, 10, 100 and 1000 mg/L). The plant height, biomass and root length indicated significant toxicity of Cd to the growth, but TiO 2 NPs exhibited the potential ability to alleviate the Cd toxicity. Transmission electron microscopy (TEM) and energy dispersive spectrometer (EDS) confirmed the existence of TiO 2 NPs in plants. Elemental analysis of Ti and Cd suggested that the presences of Cd significantly decreased the Ti accumulation in the rice roots in the co-exposure treatments. Interestingly, TiO 2 NPs could lower the Cd uptake and distribution in rice roots and leaves. The results of antioxidant enzyme activity, lipid peroxide as well as phytohormones varied in the different treatments. Comparing with the Cd alone treatment, the net photosynthetic rate and chlorophyll content were significantly increased in the co-exposure treatments, suggesting that TiO 2 NPs could tremendously reduce the Cd toxicity. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Trace elements in native and transplanted Fontinalis antipyretica and Platyhypnidium riparioides from rivers polluted by uranium mining.

PubMed

Kosior, Grzegorz; Steinnes, Eiliv; Samecka-Cymerman, Aleksandra; Lierhagen, Syverin; Kolon, Krzysztof; Dołhańczuk-Śródka, Agnieszka; Ziembik, Zbigniew

2017-03-01

The past uranium/polymetallic mining activities in the Sudety (SW Poland) left abandoned mines, pits, and dumps of waste rocks with trace elements and radionuclides which may erode or leach out and create a potential risk for the aquatic ecosystem, among others. In the present work four rivers affected by effluents from such mines were selected to evaluate the application of aquatic mosses for the bioindication of 56 elements. Naturally growing F. antipyretica and P. riparioides were compared with transplanted samples of the same species. The results demonstrate serious pollution of the examined rivers, especially with As, Ba, Fe, Mn, Pb, Ti, U and Zn, reaching extremely high concentrations in native moss samples. In the most polluted rivers native F. antipyretica and P. riparioides samples showed significantly higher concentrations of As, Ba, Cu, Fe, La, Nd, Ni, Pb, U and Zn than corresponding transplanted samples, whereas at less polluted sites a reverse situation was sometimes observed. Transplanted moss moved from clean to extremely polluted rivers probably protects itself against the accumulation of toxic elements by reducing their uptake. Selection of native or transplanted F. antipyretica and P. riparioides depended on the pollution load. Copyright © 2016. Published by Elsevier Ltd.

Germination of Medicago sativa is inhibited by soluble compounds in cement dust.

PubMed

Lafragüeta, Cristina; García-Criado, Balbino; Arranz, Angel; Vázquez-de-Aldana, Beatriz R

2014-01-01

Deposition of cement dust on soils and plant surfaces is known to affect plant growth and the species composition of plant communities, but little is known about its effects (and those of its pH and constituents) on germination. Therefore, the aim of this study was to assess the toxicity of an aqueous cement extract, constituents of the extract and pH on the germination of seeds of a selected species, Medicago sativa. First, the effects of the extract were tested in assays with concentrations and exposure durations ranging from 0 to 1.0 g/mL and 4 to 96 h, respectively. At 0.8 g/mL, the extract strongly inhibited germination; a 4-h exposure reduced the germination rate, from 77 ± 1.8 to 50 ± 2.6% (mean ± SE), while 8-h exposure completely inhibited it. Further, treatment at this concentration killed the non-germinating seeds, thus the inhibition was due to toxic effects. Neither the pH of the extract nor the concentration of its main soluble elements separately (K, Ca, S, Na, or Cr) caused the toxicity since germination rates were not significantly reduced when these variables were tested individually. However, a mixture of the elements in solution reduced germination rates, suggesting that they have adverse synergistic effects.

Estimated sediment thickness, quality, and toxicity to benthic organisms in selected impoundments in Massachusetts

USGS Publications Warehouse

Breault, Robert F.; Sorenson, Jason R.; Weiskel, Peter K.

2013-01-01

The U.S. Geological Survey and the Massachusetts Department of Fish and Game, Division of Ecological Restoration, collaborated to collect baseline information on the quantity and quality of sediment impounded behind selected dams in Massachusetts, including sediment thickness and the occurrence of contaminants potentially toxic to benthic organisms. The thicknesses of impounded sediments were measured, and cores of sediment were collected from 32 impoundments in 2004 and 2005. Cores were chemically analyzed, and concentrations of 32 inorganic elements and 108 organic compounds were quantified. Sediment thicknesses varied considerably among the 32 impoundments, with an average thickness of 3.7 feet. Estimated volumes also varied greatly, ranging from 100,000 cubic feet to 81 million cubic feet. Concentrations of toxic contaminants as well as the number of contaminants detected above analytical quantification levels (also known as laboratory reporting levels) varied greatly among sampling locations. Based on measured contaminant concentrations and comparison to published screening thresholds, bottom sediments were predicted to be toxic to bottom-dwelling (benthic) organisms in slightly under 30 percent of the impoundments sampled. Statistically significant relations were found between several of the contaminants and individual indicators of urban land use and industrial activity in the upstream drainage areas of the impoundments. However, models developed to estimate contaminant concentrations at unsampled sites from upstream landscape characteristics had low predictive power, consistent with the long and complex land-use history that is typical of many drainage areas in Massachusetts.

Measuring calcium, potassium, and nitrate in plant nutrient solutions using ion-selective electrodes in hydroponic greenhouse of some vegetables.

PubMed

Vardar, Gökay; Altıkatoğlu, Melda; Ortaç, Deniz; Cemek, Mustafa; Işıldak, İbrahim

2015-01-01

Generally, the life cycle of plants depends on the uptake of essential nutrients in a balanced manner and on toxic elements being under a certain concentration. Lack of control of nutrient levels in nutrient solution can result in reduced plant growth and undesired conditions such as blossom-end rot. In this study, sensitivity and selectivity tests for various polyvinylchloride (PVC)-based ion-selective membranes were conducted to identify those suitable for measuring typical concentration ranges of macronutrients, that is, NO(3-), K(+), and Ca(2+), in hydroponic solutions. The sensitivity and selectivity of PVC-membrane-based ion-selective sensors prepared with tetradodecylammoniumnitrate for NO(3-), valinomycin for K(+), and Ca ionophore IV for Ca(2+) were found to be satisfactory for measuring NO(3-), K(+), and Ca(2+) ions in nutrient solutions over typical ranges of hydroponic concentrations. Potassium, calcium, and nitrate levels that were utilized by cucumber and tomato seedlings in the greenhouse were different. The findings show that tomato plants consumed less amounts of nitrate than cucumber plants over the first 2 months of their growth. We also found that the potassium intake was higher than other nutritional elements tested for all plants. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

Contamination level, distribution and health risk assessment of heavy and toxic metallic and metalloid elements in a cultivated mushroom Pleurotus florida (Mont.) singer.

PubMed

Khani, Rouhollah; Moudi, Maryam; Khojeh, Vahid

2017-02-01

There are great concentrations of toxic metallic and metalloid elements such as lead, arsenic, mercury, cadmium or silver in many species of mushrooms comparative to other fruits and vegetables. In this study, contamination with heavy and toxic metallic and metalloid elements in the cultivated mushroom of (Pleurotus florida (Mont.) Singer) is investigated. P. florida was cultivated on different substrates; wheat straw (as blank), wheat straw + pine cone, wheat straw + soybean straw and wheat straw + urea and the effects of these substrates on contamination levels of Mn, Fe, Cu, Zn, As, Cd, and Pb were analyzed. The results showed that the concentrations of essential elements (Mn, Fe, Cu, and Zn) in the target mushroom are at the typical levels. The estimated daily intakes of studied metallic and metalloid elements were below their oral reference dosage mentioned by the international regulatory bodies. Health risk index (HRI) was calculated to evaluate the consumer's health risk assessment from the metal intake that contaminated in the cultivated mushroom of P. florida on the different nutrient sources. In this study, the individual HRIs were less than 1, which indicates insignificant potential health risk associated with the consumption of target mushroom from the studied substrates. Based on the HRIs values among the toxic metallic and metalloid elements, As in the target mushroom in the substrate of the wheat straw + pine cone is the main sources of risk, and it may cause severe health problems. Thus, this study suggests that the concentrations of heavy and toxic elements should be periodically monitored in cultivated mushrooms.

Effects of copyrolysis of sludge with calcium carbonate and calcium hydrogen phosphate on chemical stability of carbon and release of toxic elements in the resultant biochars.

PubMed

Xu, Xuebin; Hu, Xin; Ding, Zhuhong; Chen, Yijun

2017-12-01

The potential release of toxic elements and the stability of carbon in sludge-based biochars are important on their application in soil remediation and wastewater treatment. In this study, municipal sludge was co-pyrolyzed with calcium carbonate (CaCO 3 ) and calcium dihydrogen phosphate [Ca(H 2 PO 4 ) 2 ] under 300 and 600 °C, respectively. The basic physicochemical properties of the resultant biochars were characterized and laboratory chemical oxidation and leaching experiments of toxic elements were conducted to evaluate the chemical stability of carbon in biochars and the potential release of toxic elements from biochars. Results show that the exogenous minerals changed the physico-chemical properties of the resultant biochars greatly. Biochars with exogenous minerals, especially Ca(H 2 PO 4 ) 2 , decreased the release of Zn, Cr, Ni, Cu, Pb, and As and the release ratios were less than 1%. Tessier's sequential extraction analysis revealed that labile toxic elements were transferred to residual fraction in the biochars with high pyrolysis temperature (600 °C) and exogenous minerals. Low risks for biochar-bound Pb, Zn, Cd, As, Cr, and Cu were confirmed according to risk assessment code (RAC) while the potential ecological risk index (PERI) revealed that the exogenous Ca(H 2 PO 4 ) 2 significantly decreased the risks from considerable to moderate level. Moreover, the exogenous minerals significantly increased the chemical stability of carbon in 600 °C-pyrolyzed biochars by 10-20%. These results indicated that the copyrolysis of sludge with phosphate and carbonate, especially phosphate, were effective methods to prepare the sludge-based biochars with immobilized toxic elements and enhanced chemical stability of carbon. Copyright © 2017 Elsevier Ltd. All rights reserved.

Elemental composition of edible nuts: fast optimization and validation procedure of an ICP-OES method.

PubMed

Tošić, Snežana B; Mitić, Snežana S; Velimirović, Dragan S; Stojanović, Gordana S; Pavlović, Aleksandra N; Pecev-Marinković, Emilija T

2015-08-30

An inductively coupled plasma-optical emission spectrometry method for the speedy simultaneous detection of 19 elements in edible nuts (walnuts: Juglans nigra; almonds: Prunus dulcis; hazelnuts: Corylus avellana; Brazil nuts: Bertholletia excelsa; cashews: Anacardium occidentalle; pistachios: Pistacia vera; and peanuts: Arachis hypogaea) available on the Serbian markets, was optimized and validated through the selection of instrumental parameters and analytical lines free from spectral interference and with the lowest matrix effects. The analysed macro-elements were present in the following descending order: Na > Mg > Ca > K. Of all the trace elements, the tested samples showed the highest content of Fe. The micro-element Se was detected in all the samples of nuts. The toxic elements As, Cd and Pb were either not detected or the contents were below the limit of detection. One-way analysis of variance, Student's t-test, Tukey's HSD post hoc test and hierarchical agglomerative cluster analysis were applied in the statistical analysis of the results. Based on the detected content of analysed elements it can be concluded that nuts may be a good additional source of minerals as micronutrients. © 2014 Society of Chemical Industry.

Characterization of traffic-related ambient fine particulate matter (PM2.5) in an Asian city: Environmental and health implications

NASA Astrophysics Data System (ADS)

Zhang, Zhi-Hui; Khlystov, Andrey; Norford, Leslie K.; Tan, Zhen-Kang; Balasubramanian, Rajasekhar

2017-07-01

Vehicular traffic emission is an important source of particulate pollution in most urban areas. The detailed chemical speciation of traffic-related PM2.5 (fine particles) is relatively sparse in the literature, especially in Asian cities. To fill this knowledge gap, we carried out an intensive field study in Singapore from November 2015 to February 2016. PM2.5 samples were collected concurrently at a typical roadside microenvironment and at an urban background site. A detailed chemical speciation of PM2.5 samples was conducted to gain insights into the emission characteristics of traffic-related fine aerosols. Analyses of diagnostic ratios and molecular markers of selected chemical species were explored for source attribution of different classes of chemical constituents in traffic-related PM2.5. The human health risk due to inhalation of the particulate-bound PAHs (polycyclic aromatic hydrocarbons) and toxic trace elements was estimated for both adults and children. The overall results of the study indicate that gasoline-powered vehicles make a higher contribution to traffic-related fine aerosol components such as organic carbon (OC), particle-bound PAHs and particulate ammonium than that of diesel-powered vehicles. However, both types of vehicles contribute to traffic-related EC emissions significantly. The combustion of petroleum fuels and lubricating oil make significant contributions to the emission of n-alkanes and hopanes into the urban atmosphere, respectively. The study further reveals that some toxic trace elements are emitted from non-exhaust sources and that aromatic acids represent an important component of secondary organic aerosols. The emission of toxic trace elements from non-exhaust sources is of particular concern as they could pose a higher carcinogenic risk to both adults and children than other chemical species.

Elemental selenium at nano size possesses lower toxicity without compromising the fundamental effect on selenoenzymes: comparison with selenomethionine in mice.

PubMed

Wang, Huali; Zhang, Jinsong; Yu, Hanqing

2007-05-15

Glutathione peroxidase and thioredoxin reductase are major selenoenzymes through which selenium exerts powerful antioxidant effects. Selenium also elicits pro-oxidant effects at toxic levels. The antioxidant and pro-oxidant effects, or bioavailability and toxicity, of selenium depend on its chemical form. Selenomethionine is considered to be the most appropriate supplemental form due to its excellent bioavailability and lower toxicity compared to various selenium compounds. The present studies reveal that, compared with selenomethionine, elemental selenium at nano size (Nano-Se) possesses equal efficacy in increasing the activities of glutathione peroxidase and thioredoxin reductase but has much lower toxicity as indicated by median lethal dose, acute liver injury, and short-term toxicity. Our results suggest that Nano-Se can serve as an antioxidant with reduced risk of selenium toxicity.

Distinctive Pattern of Serum Elements During the Progression of Alzheimer’s Disease

PubMed Central

Paglia, Giuseppe; Miedico, Oto; Cristofano, Adriana; Vitale, Michela; Angiolillo, Antonella; Chiaravalle, Antonio Eugenio; Corso, Gaetano; Di Costanzo, Alfonso

2016-01-01

Element profiling is an interesting approach for understanding neurodegenerative processes, considering that compelling evidences show that element toxicity might play a crucial role in the onset and progression of Alzheimer’s disease (AD). Aim of this study was to profile 22 serum elements in subjects with or at risk of AD. Thirtyfour patients with probable AD, 20 with mild cognitive impairment (MCI), 24 with subjective memory complaint (SMC) and 40 healthy subjects (HS) were included in the study. Manganese, iron, copper, zinc, selenium, thallium, antimony, mercury, vanadium and molybdenum changed significantly among the 4 groups. Several essential elements, such as manganese, selenium, zinc and iron tended to increase in SMC and then progressively to decrease in MCI and AD. Toxic elements show a variable behavior, since some elements tended to increase, while others tended to decrease in AD. A multivariate model, built using a panel of six essential elements (manganese, iron, copper, zinc, selenium and calcium) and their ratios, discriminated AD patients from HS with over 90% accuracy. These findings suggest that essential and toxic elements contribute to generate a distinctive signature during the progression of AD, and their monitoring in elderly might help to detect preclinical stages of AD. PMID:26957294

Distinctive Pattern of Serum Elements During the Progression of Alzheimer's Disease.

PubMed

Paglia, Giuseppe; Miedico, Oto; Cristofano, Adriana; Vitale, Michela; Angiolillo, Antonella; Chiaravalle, Antonio Eugenio; Corso, Gaetano; Di Costanzo, Alfonso

2016-03-09

Element profiling is an interesting approach for understanding neurodegenerative processes, considering that compelling evidences show that element toxicity might play a crucial role in the onset and progression of Alzheimer's disease (AD). Aim of this study was to profile 22 serum elements in subjects with or at risk of AD. Thirtyfour patients with probable AD, 20 with mild cognitive impairment (MCI), 24 with subjective memory complaint (SMC) and 40 healthy subjects (HS) were included in the study. Manganese, iron, copper, zinc, selenium, thallium, antimony, mercury, vanadium and molybdenum changed significantly among the 4 groups. Several essential elements, such as manganese, selenium, zinc and iron tended to increase in SMC and then progressively to decrease in MCI and AD. Toxic elements show a variable behavior, since some elements tended to increase, while others tended to decrease in AD. A multivariate model, built using a panel of six essential elements (manganese, iron, copper, zinc, selenium and calcium) and their ratios, discriminated AD patients from HS with over 90% accuracy. These findings suggest that essential and toxic elements contribute to generate a distinctive signature during the progression of AD, and their monitoring in elderly might help to detect preclinical stages of AD.

Bioaccumulation of potentially toxic trace elements in benthic organisms of Admiralty Bay (King George Island, Antarctica).

PubMed

Majer, Alessandra Pereira; Petti, Mônica Angélica Varella; Corbisier, Thais Navajas; Ribeiro, Andreza Portella; Theophilo, Carolina Yume Sawamura; Ferreira, Paulo Alves de Lima; Figueira, Rubens Cesar Lopes

2014-02-15

Data about the concentration, accumulation and transfer of potentially toxic elements in Antarctic marine food webs are essential for understanding the impacts of these elements, and for monitoring the pollution contribution of scientific stations, mainly in Admiralty Bay due to the 2012 fire in the Brazilian scientific station. Accordingly, the concentration of As, Cd, Cu, Ni, Pb and Zn was measured in eight benthic species collected in the 2005/2006 austral summer and the relationship between concentration and trophic position (indicated by δ(15)N values) was tested. A wide variation in metal content was observed depending on the species and the element. In the studied trophic positions, it was observed bioaccumulation for As, Cd and Pb, which are toxic elements with no biological function. In addition, Cd showed a positive relationship between concentration and trophic level suggesting the possible biomagnification of this element. Copyright © 2013 Elsevier Ltd. All rights reserved.

A functional metagenomic approach for expanding the synthetic biology toolbox for biomass conversion

PubMed Central

Sommer, Morten OA; Church, George M; Dantas, Gautam

2010-01-01

Sustainable biofuel alternatives to fossil fuel energy are hampered by recalcitrance and toxicity of biomass substrates to microbial biocatalysts. To address this issue, we present a culture-independent functional metagenomic platform for mining Nature's vast enzymatic reservoir and show its relevance to biomass conversion. We performed functional selections on 4.7 Gb of metagenomic fosmid libraries and show that genetic elements conferring tolerance toward seven important biomass inhibitors can be identified. We select two metagenomic fosmids that improve the growth of Escherichia coli by 5.7- and 6.9-fold in the presence of inhibitory concentrations of syringaldehyde and 2-furoic acid, respectively, and identify the individual genes responsible for these tolerance phenotypes. Finally, we combine the individual genes to create a three-gene construct that confers tolerance to mixtures of these important biomass inhibitors. This platform presents a route for expanding the repertoire of genetic elements available to synthetic biology and provides a starting point for efforts to engineer robust strains for biofuel generation. PMID:20393580

Deficiencies and toxicities of trace elements and micronutrients in tropical soils: Limitations of knowledge and future research needs

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

Davies, B.E.

1997-01-01

This article reviews present knowledge concerning deficiencies and toxicities of trace elements and micronutrients in tropical soils. The myth that all tropical soils are highly leached and nutrient-poor is challenged. Continuing use of the term laterite by ecologists and geologists is criticized and adoption of plinthite is urged. The trace element content of plinthite and its possible influence on micronutrient availability are described. Micronutrient limitations of tropical agriculture are related to soil type and formation, and the special problem of aluminum toxicity in acid soils is discussed in both agricultural and ecological contexts. Studies of micronutrient cycling in tropical forestsmore » or savannas are needed to supplement the emerging picture of the complexities of major element cycles in these ecosystems.« less

Efficiency Evaluation of Food Waste Materials for the Removal of Metals and Metalloids from Complex Multi-Element Solutions.

PubMed

Massimi, Lorenzo; Giuliano, Antonella; Astolfi, Maria Luisa; Congedo, Rossana; Masotti, Andrea; Canepari, Silvia

2018-02-26

Recent studies have shown the potential of food waste materials as low cost adsorbents for the removal of heavy metals and toxic elements from wastewater. However, the adsorption experiments have been performed in heterogeneous conditions, consequently it is difficult to compare the efficiency of the individual adsorbents. In this study, the adsorption capacities of 12 food waste materials were evaluated by comparing the adsorbents' efficiency for the removal of 23 elements from complex multi-element solutions, maintaining homogeneous experimental conditions. The examined materials resulted to be extremely efficient for the adsorption of many elements from synthetic multi-element solutions as well as from a heavy metal wastewater. The 12 adsorbent surfaces were analyzed by Fourier transform infrared spectroscopy and showed different types and amounts of functional groups, which demonstrated to act as adsorption active sites for various elements. By multivariate statistical computations of the obtained data, the 12 food waste materials were grouped in five clusters characterized by different elements' removal efficiency which resulted to be in correlation with the specific adsorbents' chemical structures. Banana peel, watermelon peel and grape waste resulted the least selective and the most efficient food waste materials for the removal of most of the elements.

Recovery of toxic metal ions from washing effluent containing excess aminopolycarboxylate chelant in solution.

PubMed

Hasegawa, Hiroshi; Rahman, Ismail M M; Nakano, Masayoshi; Begum, Zinnat A; Egawa, Yuji; Maki, Teruya; Furusho, Yoshiaki; Mizutani, Satoshi

2011-10-15

Aminopolycarboxylate chelants (APCs) are extremely useful for a variety of industrial applications, including the treatment of toxic metal-contaminated solid waste materials. Because non-toxic matrix elements compete with toxic metals for the binding sites of APCs, an excess of chelant is commonly added to ensure the adequate sequestration of toxic metal contaminants during waste treatment operations. The major environmental impacts of APCs are related to their ability to solubilize toxic heavy metals. If APCs are not sufficiently eliminated from the effluent, the aqueous transport of metals can occur through the introduction of APCs into the natural environment, increasing the magnitude of associated toxicity. Although several techniques that focus primarily on the degradation of APCs at the pre-release step have been proposed, methods that recycle not only the processed water, but also provide the option to recover and reuse the metals, might be economically feasible, considering the high costs involved due to the chelants used in metal ion sequestration. In this paper, we propose a separation process for the recovery of metals from effluents that contain an excess of APCs. Additionally, the option of recycling the processed water using a solid phase extraction (SPE) system with an ion-selective immobilized macrocyclic material, commonly known as a molecular recognition technology (MRT) gel, is presented. Simulated effluents containing As(V), Cd(II), Cr(III), Pb(II) or Se(IV) in the presence of APCs at molar ratios of 1:50 in H2O were studied with a flow rate of 0.2 mL min(-1). The 'captured' ions in the SPE system were quantitatively eluted with HNO3. The effects of solution pH, metal-chelant stability constants and matrix elements were assessed. Better separation performance for the metals was achieved with the MRT-SPE compared to other SPE materials. Our proposed technique offers the advantage of a non-destructive separation of both metal ions and chelants compared to conventional treatment options for such effluents. Copyright © 2011 Elsevier Ltd. All rights reserved.

Toxic Elements in Different Medicinal Plants and the Impact on Human Health

PubMed Central

Brima, Eid I.

2017-01-01

Local medicinal plants from Madina, Saudi Arabia, are used to cure various diseases. However, some can cause adverse health effects. Five different medicinal plants were collected in the city of Madina: mahareeb (Cymbopogon), sheeh (Artemisia), harjal (Cynanchum argel delile), nabipoot (Equisetum), and kafmariam (Vitex agnus-castus). In total, four toxic elements including Al, Pb, As, and Cd were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The range of recoveries fell between 86.1 and 90.6% for all measured elements. Al levels were the highest of any of the studied elements in all plant samples, with Cymbopogon showing the highest levels. The range of concentrations of Al was 156–1609 mg/kg. Cd appeared at the lowest levels in all plants samples, with Vitex agnus-castus containing this element at the highest levels. Cd concentrations were in the range of 0.01–0.10 mg/kg. A washing process lowered the toxic elements in all plants; average % recoveries were Al (47.32%), As (59.1%), Cd (62.03%), and Pb (32.40%). The calculated human health risk assessment in one dose for toxic elements in all plants was as follows: Al (1.33 × 10−3–5.57 × 10−2 mg/kg.bw), Pb (0–8.86 × 10−5 mg/kg.bw), As (3.43 × 10−7–1.33 × 10−5 mg/kg.bw), and Cd (0–3.14 × 10−6 mg/kg.bw). Medicinal plants are a source of exposure to toxic elements. However, none of the plants in this study exceeded the daily guideline set by the WHO for any element based on conventional use by the local population. We may cautiously conclude that these medicinal plants pose no risk to users based on conventional use. PMID:29019913

Determination of minor and trace elements in aromatic spices by micro-wave assisted digestion and inductively coupled plasma-mass spectrometry.

PubMed

Khan, Naeem; Choi, Ji Yeon; Nho, Eun Yeong; Jamila, Nargis; Habte, Girum; Hong, Joon Ho; Hwang, In Min; Kim, Kyong Su

2014-09-01

This study aimed at analyzing the concentrations of 23 minor and trace elements in aromatic spices by inductively coupled plasma-mass spectrometry (ICP-MS), after wet digestion by microwave system. The analytical method was validated by linearity, detection limits, precision, accuracy and recovery experiments, obtaining satisfactory values in all cases. Results indicated the presence of variable amounts of both minor and trace elements in the selected aromatic spices. Manganese was high in cinnamon (879.8 μg/g) followed by cardamom (758.1 μg/g) and clove (649.9 μg/g), strontium and zinc were high in ajwain (489.9 μg/g and 84.95 μg/g, respectively), while copper was high in mango powder (77.68 μg/g). On the whole some of the minor and essential trace elements were found to have good nutritional contribution in accordance to RDA. The levels of toxic trace elements, including As, Cd, and Pb were very low and did not found to pose any threat to consumers. Copyright © 2014 Elsevier Ltd. All rights reserved.

Toxicity of irradiated advanced heavy water reactor fuels.

PubMed

Priest, N D; Richardson, R B; Edwards, G W R

2013-02-01

The good neutron economy and online refueling capability of the CANDU® heavy water moderated reactor (HWR) enable it to use many different fuels such as low enriched uranium (LEU), plutonium, or thorium, in addition to its traditional natural uranium (NU) fuel. The toxicity and radiological protection methods for these proposed fuels, unlike those for NU, are not well established. This study uses software to compare the fuel composition and toxicity of irradiated NU fuel against those of two irradiated advanced HWR fuel bundles as a function of post-irradiation time. The first bundle investigated is a CANFLEX® low void reactor fuel (LVRF), of which only the dysprosium-poisoned central element, and not the outer 42 LEU elements, is specifically analyzed. The second bundle investigated is a heterogeneous high-burnup (LEU,Th)O(2) fuelled bundle, whose two components (LEU in the outer 35 elements and thorium in the central eight elements) are analyzed separately. The LVRF central element was estimated to have a much lower toxicity than that of NU at all times after shutdown. Both the high burnup LEU and the thorium fuel had similar toxicity to NU at shutdown, but due to the creation of such inhalation hazards as (238)Pu, (240)Pu, (242)Am, (242)Cm, and (244)Cm (in high burnup LEU), and (232)U and (228)Th (in irradiated thorium), the toxicity of these fuels was almost double that of irradiated NU after 2,700 d of cooling. New urine bioassay methods for higher actinoids and the analysis of thorium in fecal samples are recommended to assess the internal dose from these two fuels.

Trace elements in streambed sediments of small subtropical streams on O'ahu, Hawai'i: Results from the USGS NAWQA program

USGS Publications Warehouse

De Carlo, E. H.; Tomlinson, M.S.; Anthony, S.S.

2005-01-01

Data are presented for trace element concentrations determined in the <63 ??m fraction of streambed sediment samples collected at 24 sites on the island of O'ahu, Hawai'i. Sampling sites were classified as urban, agricultural, mixed (urban/agricultural), or forested based on their dominant land use, although the mixed land use at selected sampling sites consisted of either urban and agricultural or forested and agricultural land uses. Forest dominated sites were used as reference sites for calculating enrichment factors. Trace element concentrations were compared to concentrations from studies conducted in the conterminous United States using identical methods and to aquatic-life guidelines provided by the Canadian Council of Ministers of the Environment. A variety of elements including Pb, Cr, Cu and Zn exceeded the aquatic-life guidelines in selected samples. All of the Cr and Zn values and 16 of 24 Cu values exceeded their respective guidelines. The potential toxicity of elements exceeding guidelines, however, should be considered in the context of strong enrichments of selected trace elements attributable to source rocks in Hawai'i, as well as in the context of the abundance of fine-grained sediment in the streambed of O'ahu streams. Statistical methods including cluster analysis, Kruskal-Wallis non-parametric test, correlation analysis, and principal component analysis (PCA) were used to evaluate differences and elucidate relationships between trace elements and sites. Overall, trace element distributions and abundances can be correlated to three principal sources of elements. These include basaltic rocks of the volcanic edifice (Fe, Al, Ni, Co, Cr, V and Cu), carbonate/seawater derived elements (Mg, Ca, Na and Sr), and elements enriched owing to anthropogenic activity (P, Sn, Cd, Sn, Ba and Pb). Anthropogenic enrichment gradients were observed for Ba, Cd, Pb, Sn and Zn in the four streams in which sediments were collected upstream and downstream. The findings of this study are generally similar to but differ slightly from previous work on sediments and suspended particulate matter in streams, from two urban watersheds of O'ahu, Hawai'i. Inter-element associations in the latter were often stronger and indicated a mixture of anthropogenic, agricultural and basaltic sources of trace elements. Some elements fell into different statistical categories in the two studies, owing in part to differences in study design and the hydrogeological constraints on the respective study areas.

Maternal-child transfer of essential and toxic elements through breast milk in a mine-waste polluted area.

PubMed

Castro, Francisca; Harari, Florencia; Llanos, Miguel; Vahter, Marie; Ronco, Ana Maria

2014-11-01

To determine the daily intake of essential micronutrients and toxic elements through breast milk in exclusive and nonexclusive breastfed infants living in an area with major mine tailing deposition (n = 24), compared with a control area (n = 11). The milk volume ingested by 2 to 4 and 4 to 6 month infants was measured by a stable isotopic method. Elements in milk, maternal and infant urine, and drinking water were measured by inductively coupled plasma mass spectrometry (ICP-MS). Similar breast milk volume and essential micronutrients intake in groups of exclusively breastfed infants, but more cadmium, boron, and lithium through breastfeeding in experimental area was found. This exposure was even higher in the nonexclusively breastfed infants, who also ingested more arsenic, boron, and lithium than exclusive breastfed infants. The use of the deuterium and the ICP-MS methods made it possible to evaluate the exact amount of essential and toxic elements ingested by infants through breast milk demonstrating that lower amount of toxic elements are transferred to exclusive breastfed infants compared with those who additionally received nonmaternal milk. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Chemical composition of selected seaweeds from the Indian Ocean, KwaZulu-Natal coast, South Africa.

PubMed

Magura, Judie; Moodley, Roshila; Jonnalagadda, Sreekantha B

2016-08-02

The chemical composition of three edible seaweeds (Codium capitatum, Hypnea spicifera and Sargassum elegans) and two inedible seaweeds (Halimeda cuneata and Spyridia hypnoides) from the Indian Ocean along the KwaZulu-Natal East Coast, South Africa were investigated as a function of seasonal variation. The proximate compositions of the edible seaweeds were determined. In edible seaweeds, the moisture level ranged from 85.4 to 89.5%, protein from 6.1 to 11.8%, lipids from 7.5 to 13.1% and carbohydrates from 37.8 to 71.9%. Elemental concentrations in the five studied seaweeds varied significantly with season (P < 0.05) with mean elemental concentrations (in µg g(-1), dry weight) being: Ca (29 260), Mg (6 279), Fe (1 086), Cu (145.9), Mn (48.32), As (24.29), Zn (15.65), Ni (9.83), Cr (5.78), Pb (4.84), Co (0.87) and Se (0.86). The concentrations of As were particularly high in S. elegans, ranging from 94.70 ± 6.6 µg g(-1) in winter to 65.10 ± 2.3 µg g(-1) in summer. Hierarchical cluster analysis showed similar distribution of elements in edible seaweeds which was dissimilar to that in inedible seaweeds. This study suggests that edible macro alga, C. capitatum and H. spicifera, could be potential sources of most essential nutrients and may contribute positively to the diet without posing the risk of adverse health effects due to low concentrations of toxic elements. However, due to high levels of As in S. elegans, its consumption should be moderated to reduce dietary exposure to this toxic element.

Arsenic: A Review of the Element's Toxicity, Plant Interactions, and Potential Methods of Remediation.

PubMed

Hettick, Bryan E; Cañas-Carrell, Jaclyn E; French, Amanda D; Klein, David M

2015-08-19

Arsenic is a naturally occurring element with a long history of toxicity. Sites of contamination are found worldwide as a result of both natural processes and anthropogenic activities. The broad scope of arsenic toxicity to humans and its unique interaction with the environment have led to extensive research into its physicochemical properties and toxic behavior in biological systems. The purpose of this review is to compile the results of recent studies concerning the metalloid and consider the chemical and physical properties of arsenic in the broad context of human toxicity and phytoremediation. Areas of focus include arsenic's mechanisms of human toxicity, interaction with plant systems, potential methods of remediation, and protocols for the determination of metals in experimentation. This assessment of the literature indicates that controlling contamination of water sources and plants through effective remediation and management is essential to successfully addressing the problems of arsenic toxicity and contamination.

Nicotine, aerosol particles, carbonyls and volatile organic compounds in tobacco- and menthol-flavored e-cigarettes.

PubMed

Lee, Mi-Sun; LeBouf, Ryan F; Son, Youn-Suk; Koutrakis, Petros; Christiani, David C

2017-04-27

We aimed to assess the content of electronic cigarette (EC) emissions for five groups of potentially toxic compounds that are known to be present in tobacco smoke: nicotine, particles, carbonyls, volatile organic compounds (VOCs), and trace elements by flavor and puffing time. We used ECs containing a common nicotine strength (1.8%) and the most popular flavors, tobacco and menthol. An automatic multiple smoking machine was used to generate EC aerosols under controlled conditions. Using a dilution chamber, we targeted nicotine concentrations similar to that of exposure in a general indoor environment. The selected toxic compounds were extracted from EC aerosols into a solid or liquid phase and analyzed with chromatographic and spectroscopic methods. We found that EC aerosols contained toxic compounds including nicotine, fine and nanoparticles, carbonyls, and some toxic VOCs such as benzene and toluene. Higher mass and number concentrations of aerosol particles were generated from tobacco-flavored ECs than from menthol-flavored ECs. We found that diluted machine-generated EC aerosols contain some pollutants. These findings are limited by the small number of ECs tested and the conditions of testing. More comprehensive research on EC exposure extending to more brands and flavor compounds is warranted.

Trace elements have beneficial, as well as detrimental effects on bone homeostasis.

PubMed

Zofkova, I; Davis, M; Blahos, J

2017-07-18

The protective role of nutrition factors such as calcium, vitamin D and vitamin K for the integrity of the skeleton is well understood. In addition, integrity of the skeleton is positively influenced by certain trace elements (e.g. zinc, copper, manganese, magnesium, iron, selenium, boron and fluoride) and negatively by others (lead, cadmium, cobalt). Deficiency or excess of these elements influence bone mass and bone quality in adulthood as well as in childhood and adolescence. However, some protective elements may become toxic under certain conditions, depending on dosage (serum concentration), duration of treatment and interactions among individual elements. We review the beneficial and toxic effects of key elements on bone homeostasis.

Efficiency Evaluation of Food Waste Materials for the Removal of Metals and Metalloids from Complex Multi-Element Solutions

PubMed Central

Giuliano, Antonella; Astolfi, Maria Luisa; Congedo, Rossana; Masotti, Andrea; Canepari, Silvia

2018-01-01

Recent studies have shown the potential of food waste materials as low cost adsorbents for the removal of heavy metals and toxic elements from wastewater. However, the adsorption experiments have been performed in heterogeneous conditions, consequently it is difficult to compare the efficiency of the individual adsorbents. In this study, the adsorption capacities of 12 food waste materials were evaluated by comparing the adsorbents’ efficiency for the removal of 23 elements from complex multi-element solutions, maintaining homogeneous experimental conditions. The examined materials resulted to be extremely efficient for the adsorption of many elements from synthetic multi-element solutions as well as from a heavy metal wastewater. The 12 adsorbent surfaces were analyzed by Fourier transform infrared spectroscopy and showed different types and amounts of functional groups, which demonstrated to act as adsorption active sites for various elements. By multivariate statistical computations of the obtained data, the 12 food waste materials were grouped in five clusters characterized by different elements’ removal efficiency which resulted to be in correlation with the specific adsorbents’ chemical structures. Banana peel, watermelon peel and grape waste resulted the least selective and the most efficient food waste materials for the removal of most of the elements. PMID:29495363

[Effects of rare earth elements on soil fauna community structure and their ecotoxicity to Holotrichia parallela].

PubMed

Li, Guiting; Jiang, Junqi; Chen, Jie; Zou, Yunding; Zhang, Xincai

2006-01-01

By the method of OECD filter paper contact, this paper studied the effects of applied rare earth elements on soil fauna community structure and their ecological toxicity to Holotrichia parallela in bean field. The results showed that there were no significant differences between the treatments and the control in soil fauna species, quantity of main species, and diversity index. Urgent and chronic toxic test showed that the differences between the treatments and the control were not significant. It was suggested that within the range of test dosages, rare earth elements had little ecological toxicity to Holotrichia parallela, and did not change the soil fauna community structure.

Toxic Trace Elements in the Hair of Children with Autism

ERIC Educational Resources Information Center

Fido, Abdullahi; Al-Saad, Samira

2005-01-01

Excess or deficiency of natural trace elements has been implicated in the etiology of autism. This study explores whether concentration levels of toxic metals in the hair of children with autism significantly differ from those of age- and sex-matched healthy controls. In-hair concentration levels of antimony, uranium, arsenic, beryllium, mercury,…

Control of trace element toxicity in Chesapeake Bay by dominant phytoplankton. Final report

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

Sanders, J.G.; Riedel, G.F.; Connell, D.B.

1992-02-01

Copper (Cu) and arsenic (As), but not chromium (Cr), underwent large changes in chemical form during the development and senescence of natural phytoplankton blooms. In general, the percentage of organically-associated Cu was lowest during periods of rapid cell growth and highest during periods of cell decline or periods of dominance by red tide-forming dinoflagellates, a pattern tied to periods of release of organic compounds during either bloom senescence or during unusual algal blooms. Chromium, in contrast, was unreactive. The end result of biological mediation of both As and Cu was to increase the proportion of the element present in amore » less toxic form, at least to phytoplankton, thus affecting the potential toxicity of either element to a natural ecosystem. The results of the project provide a framework for the construction of general predictive models of likely trace element behavior in productive ecosystems and provide a conceptual theory of how such toxic contaminants may affect ecosystem structure and food webs within Chesapeake Bay. Predictive models of ecosystem impact will require further experimentation with multi-trophic level food chains.« less

Elemental selenium at nano size (Nano-Se) as a potential chemopreventive agent with reduced risk of selenium toxicity: comparison with se-methylselenocysteine in mice.

PubMed

Zhang, Jinsong; Wang, Xufang; Xu, Tongwen

2008-01-01

Selenium (Se) is an essential trace element with a narrow margin between beneficial and toxic effects. As a promising chemopreventive agent, its use requires consumption over the long term, so the toxicity of Se is always a crucial concern. Based on clinical findings and recent studies in selenoprotein gene-modified mice, it is likely that the antioxidant function of one or more selenoproteins is responsible for the chemopreventive effect of Se. Furthermore, upregulation of phase 2 enzymes by Se has been implicated as a possible chemopreventive mechanism at supranutritional dietary levels. Se-methylselenocysteine (SeMSC), a naturally occurring organic Se product, is considered as one of the most effective chemopreventive selenocompounds. The present study revealed that, as compared with SeMSC, elemental Se at nano size (Nano-Se) possessed equal efficacy in increasing the activities of glutathione peroxidase, thioredoxin reductase, and glutathione S-transferase, but had much lower toxicity as indicated by median lethal dose, acute liver injury, survival rate, and short-term toxicity. Our results suggest that Nano-Se can serve as a potential chemopreventive agent with reduced risk of Se toxicity.

Baseline susceptibility of Planococcus ficus (Hemiptera: Pseudococcidae) from California to select insecticides.

PubMed

Prabhaker, Nilima; Gispert, Carmen; Castle, Steven J

2012-08-01

Between 2006 and 2008, 20 populations of Planococcus ficus (Signoret), from Coachella and San Joaquin Valleys of California were measured in the laboratory for susceptibility to buprofezin, chlorpyrifos, dimethoate, methomyl, and imidacloprid. Toxicity was assessed using a petri dish bioassay technique for contact insecticides and by a systemic uptake technique for imidacloprid. Mixed life stages were tested for susceptibility to all insecticides except for buprofezin, which was measured against early and late instars (first, second, and third). Dose-response regression lines from the mortality data established LC50 and LC99 values by both techniques. Responses of populations from the two geographical locations to all five insecticides varied, in some cases significantly. Variations in susceptibility to each insecticide among sample sites showed a sevenfold difference for buprofezin, 11-fold to chlorpyrifos, ninefold to dimethoate, 24-fold to methomyl, and 8.5-fold to imidacloprid. In spite of susceptibility differences between populations, baseline toxicity data revealed that all five insecticides were quite effective based on low LC50s. Chlorpyrifos was the most toxic compound to Planococcus ficus populations as shown by lowest LC50s. Buprofezin was toxic to all immature stages but was more potent to first instars. The highest LC99 estimated by probit analysis of the bioassay data of all 20 populations for each compound was selected as a candidate discriminating dose for use in future resistance monitoring efforts. Establishment of baseline data and development of resistance monitoring tools such as bioassay methods and discriminating doses are essential elements of a sustainable management program for Planococcus ficus.

Estimating children's exposure to toxic elements in contaminated toys and children's jewelry via saliva mobilization.

PubMed

Guney, Mert; Nguyen, Alain; Zagury, Gerald J

2014-09-19

Children's potential for exposure to potentially toxic elements in contaminated jewelry and toys via mouth contact has not yet been fully evaluated. Various toys and jewelry (metallic toys and jewelry [MJ], plastic toys, toys with paint or coating, and brittle/pliable toys; n = 32) were tested using the saliva extraction (mouthing) compartment of the DIN and RIVM bioaccessibility protocols to assess As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, Sb, and Se mobilization via saliva. Total concentrations of As, Cd, Cu, Ni, Pb, and Sb were found elevated in analyzed samples. Four metals were mobilized to saliva from 16 MJ in significant quantities (>1 μg for highly toxic Cd and Pb, >10 μg for Cu and Ni). Bioaccessible concentrations and hazard index values for Cd exceeded limit values, for young children between 6 mo- and 3 yr-old and according to both protocols. Total and bioaccessible metal concentrations were different and not always correlated, encouraging the use of bioaccessibility for more accurate hazard assessments. Bioaccessibility increased with increasing extraction time. Overall, the risk from exposure to toxic elements via mouthing was high only for Cd and for MJ. Further research on children's exposure to toxic elements following ingestion of toy or jewelry material is recommended.

The Role of Intermetal Competition and Mis-Metalation in Metal Toxicity.

PubMed

Barwinska-Sendra, Anna; Waldron, Kevin J

2017-01-01

The metals manganese, iron, cobalt, nickel, copper and zinc are essential for almost all bacteria, but their precise metal requirements vary by species, by ecological niche and by growth condition. Bacteria thus must acquire each of these essential elements in sufficient quantity to satisfy their cellular demand, but in excess these same elements are toxic. Metal toxicity has been exploited by humanity for centuries, and by the mammalian immune system for far longer, yet the mechanisms by which these elements cause toxicity to bacteria are not fully understood. There has been a resurgence of interest in metal toxicity in recent decades due to the problematic spread of antibiotic resistance amongst bacterial pathogens, which has led to an increased research effort to understand these toxicity mechanisms at the molecular level. A recurring theme from these studies is the role of intermetal competition in bacterial metal toxicity. In this review, we first survey biological metal usage and introduce some fundamental chemical concepts that are important for understanding bacterial metal usage and toxicity. Then we introduce a simple model by which to understand bacterial metal homeostasis in terms of the distribution of each essential metal ion within cellular 'pools', and dissect how these pools interact with each other and with key proteins of bacterial metal homeostasis. Finally, using a number of key examples from the recent literature, we look at specific metal toxicity mechanisms in model bacteria, demonstrating the role of metal-metal competition in the toxicity mechanisms of diverse essential metals. © 2017 Elsevier Ltd. All rights reserved.

Studies on the toxic elements and organic degradation products in aquatic bodies and sediments around Kennedy Space Center (KSC) South Mosquito lagoon

NASA Technical Reports Server (NTRS)

Ghuman, G. S.; Menon, M. P.; Emeh, C. O.

1978-01-01

A compilation was put together of research work performed on the aquatic systems around Kennedy Space Center (KSC). The report includes a brief description of the study area, field data and analytical results of all the samples collected during the five visits to KSC up to December 17, 1977. The aquatic area selected for the study is the Southern part of Mosquito Lagoon which extends from the Haulover Canal to the dead end boundary of this lagoon southwards.

Use of human milk in the assessment of toxic metal exposure and essential element status in breastfeeding women and their infants in coastal Croatia.

PubMed

Grzunov Letinić, Judita; Matek Sarić, Marijana; Piasek, Martina; Jurasović, Jasna; Varnai, Veda Marija; Sulimanec Grgec, Antonija; Orct, Tatjana

2016-12-01

Pregnant and lactating women and infants are vulnerable population groups for adverse effects of toxic metals due to their high nutritional needs and the resultant increased gastrointestinal absorption of both, essential and toxic elements. Although breastfeeding is recommended for infants worldwide, as human milk is the best source of nutrients and other required bioactive factors, it is also a pathway of maternal excretion of toxic substances including toxic metals and thus a source of infant exposure. The aim of this research was to assess health risks in breastfeeding women in the coastal area of the Republic of Croatia and their infants (N=107) due to maternal exposure to Cd and Pb via cigarette smoking, and Hg via seafood and dental amalgam fillings, and their interaction with essential elements. Biological markers of exposure were the concentrations of main toxic metals Pb, Cd and Hg in maternal blood and three types of breast milk throughout lactation stages. Biological markers of effects were the levels of essential elements Ca, Fe, Cu, Zn and Se in maternal serum and breast milk. With regard to cigarette smoking as a source of exposure to Cd and Pb, there were effects of smoking on Cd concentration in blood and correlations between the smoking index and Cd concentrations in maternal blood (ρ=0.593; P<0.001) and mature milk (ρ=0.271; P=0.011) and Pb concentration in transitional milk (ρ=0.280; P=0.042). Regarding fish, we found correlations between weekly consumption frequency and total Hg concentrations in maternal blood (ρ=0.292; P=0.003) and mature milk (ρ=0.303; P=0.003). The number of dental amalgam fillings correlated with total Hg concentrations in colostrum (ρ=0.489; P=0.005) and transitional milk (ρ=0.309; P=0.018). As for the essential element status, only Se levels in maternal serum decreased by 10% in persons who continued smoking during pregnancy compared to non-smokers. In conclusion, the levels of main toxic metals Cd, Pb and Hg and essential elements Ca, Fe, Cu, Zn and Se in maternal blood and three types of breast milk samples in the studied area of coastal Croatia showed no risk of disrupted essential element levels with regard of toxic metal exposure in both breastfeeding women and their infants. Copyright © 2016 Elsevier GmbH. All rights reserved.

Elemental mercury contamination survey in a chlor-alkali plant by the use of transplanted Spanish moss, Tillandsia usneoides (L.).

PubMed

Calasans, C F; Malm, O

1997-12-22

Atmospheric Hg0 contamination and the potential risk of occupational exposure were evaluated in a chlor-alkali facility by the use of transplanted Tillandsia usneoides. This plant species was selected since it presents some features that makes it useful for air monitoring purposes. After short-term exposure (15 days), control plants showed a mean concentration of 0.2 microgram Hg.g-1 whereas Hg values in transplants ranged from 1 to 10,400 micrograms.g-1. This latter value was observed near an elemental Hg spillage. Even after exposure to toxic conditions plant metabolism was still operative, allowing the transplant technique to be employed to assess both Hg taken up through the stomata and Hg associated with particles deposited on the biomonitor.

Trace elements in dialysis.

PubMed

Filler, Guido; Felder, Sarah

2014-08-01

In end-stage chronic kidney disease (CKD), pediatric nephrologists must consider the homeostasis of the multiple water-soluble ions that are influenced by renal replacement therapy (RRT). While certain ions such as potassium and calcium are closely monitored, little is known about the handling of trace elements in pediatric dialysis. RRT may lead to accumulation of toxic trace elements, either due to insufficient elimination or due to contamination, or to excessive removal of essential trace elements. However, trace elements are not routinely monitored in dialysis patients and no mechanism for these deficits or toxicities has been established. This review summarizes the handling of trace elements, with particular attention to pediatric data. The best data describe lead and indicate that there is a higher prevalence of elevated lead (Pb, atomic number 82) levels in children on RRT when compared to adults. Lead is particularly toxic in neurodevelopment and lead levels should therefore be monitored. Monitoring of zinc (Zn, atomic number 30) and selenium (Se, atomic number 34) may be indicated in the monitoring of all pediatric dialysis patients to reduce morbidity from deficiency. Prospective studies evaluating the impact of abnormal trace elements and the possible therapeutic value of intervention are required.

Principles for characterizing the potential human health effects from exposure to nanomaterials: elements of a screening strategy

PubMed Central

Oberdörster, Günter; Maynard, Andrew; Donaldson, Ken; Castranova, Vincent; Fitzpatrick, Julie; Ausman, Kevin; Carter, Janet; Karn, Barbara; Kreyling, Wolfgang; Lai, David; Olin, Stephen; Monteiro-Riviere, Nancy; Warheit, David; Yang, Hong

2005-01-01

The rapid proliferation of many different engineered nanomaterials (defined as materials designed and produced to have structural features with at least one dimension of 100 nanometers or less) presents a dilemma to regulators regarding hazard identification. The International Life Sciences Institute Research Foundation/Risk Science Institute convened an expert working group to develop a screening strategy for the hazard identification of engineered nanomaterials. The working group report presents the elements of a screening strategy rather than a detailed testing protocol. Based on an evaluation of the limited data currently available, the report presents a broad data gathering strategy applicable to this early stage in the development of a risk assessment process for nanomaterials. Oral, dermal, inhalation, and injection routes of exposure are included recognizing that, depending on use patterns, exposure to nanomaterials may occur by any of these routes. The three key elements of the toxicity screening strategy are: Physicochemical Characteristics, In Vitro Assays (cellular and non-cellular), and In Vivo Assays. There is a strong likelihood that biological activity of nanoparticles will depend on physicochemical parameters not routinely considered in toxicity screening studies. Physicochemical properties that may be important in understanding the toxic effects of test materials include particle size and size distribution, agglomeration state, shape, crystal structure, chemical composition, surface area, surface chemistry, surface charge, and porosity. In vitro techniques allow specific biological and mechanistic pathways to be isolated and tested under controlled conditions, in ways that are not feasible in in vivo tests. Tests are suggested for portal-of-entry toxicity for lungs, skin, and the mucosal membranes, and target organ toxicity for endothelium, blood, spleen, liver, nervous system, heart, and kidney. Non-cellular assessment of nanoparticle durability, protein interactions, complement activation, and pro-oxidant activity is also considered. Tier 1 in vivo assays are proposed for pulmonary, oral, skin and injection exposures, and Tier 2 evaluations for pulmonary exposures are also proposed. Tier 1 evaluations include markers of inflammation, oxidant stress, and cell proliferation in portal-of-entry and selected remote organs and tissues. Tier 2 evaluations for pulmonary exposures could include deposition, translocation, and toxicokinetics and biopersistence studies; effects of multiple exposures; potential effects on the reproductive system, placenta, and fetus; alternative animal models; and mechanistic studies. PMID:16209704

The Impact of a Nickel-Copper Smelter on Concentrations of Toxic Elements in Local Wild Food from the Norwegian, Finnish, and Russian Border Regions

PubMed Central

Hansen, Martine D.; Nøst, Therese H.; Heimstad, Eldbjørg S.; Evenset, Anita; Dudarev, Alexey A.; Rautio, Arja; Myllynen, Päivi; Dushkina, Eugenia V.; Jagodic, Marta; Christensen, Guttorm N.; Anda, Erik E.; Brustad, Magritt; Sandanger, Torkjel M.

2017-01-01

Toxic elements emitted from the Pechenganickel complex on the Kola Peninsula have caused concern about potential effects on local wild food in the border regions between Norway, Finland and Russia. The aim of this study was to assess Ni, Cu, Co, As, Pb, Cd, and Hg concentrations in local wild foods from these border regions. During 2013–2014, we collected samples of different berry, mushroom, fish, and game species from sites at varying distances from the Ni-Cu smelter in all three border regions. Our results indicate that the Ni-Cu smelter is the main source of Ni, Co, and As in local wild foods, whereas the sources of Pb and Cd are more complex. We observed no consistent trends for Cu, one of the main toxic elements emitted by the Ni-Cu smelter; nor did we find any trend for Hg in wild food. Concentrations of all investigated toxic elements were highest in mushrooms, except for Hg, which was highest in fish. EU maximum levels of Pb, Cd, and Hg were exceeded in some samples, but most had levels considered safe for human consumption. No international thresholds exist for the other elements under study. PMID:28657608

The Impact of a Nickel-Copper Smelter on Concentrations of Toxic Elements in Local Wild Food from the Norwegian, Finnish, and Russian Border Regions.

PubMed

Hansen, Martine D; Nøst, Therese H; Heimstad, Eldbjørg S; Evenset, Anita; Dudarev, Alexey A; Rautio, Arja; Myllynen, Päivi; Dushkina, Eugenia V; Jagodic, Marta; Christensen, Guttorm N; Anda, Erik E; Brustad, Magritt; Sandanger, Torkjel M

2017-06-28

Toxic elements emitted from the Pechenganickel complex on the Kola Peninsula have caused concern about potential effects on local wild food in the border regions between Norway, Finland and Russia. The aim of this study was to assess Ni, Cu, Co, As, Pb, Cd, and Hg concentrations in local wild foods from these border regions. During 2013-2014, we collected samples of different berry, mushroom, fish, and game species from sites at varying distances from the Ni-Cu smelter in all three border regions. Our results indicate that the Ni-Cu smelter is the main source of Ni, Co, and As in local wild foods, whereas the sources of Pb and Cd are more complex. We observed no consistent trends for Cu, one of the main toxic elements emitted by the Ni-Cu smelter; nor did we find any trend for Hg in wild food. Concentrations of all investigated toxic elements were highest in mushrooms, except for Hg, which was highest in fish. EU maximum levels of Pb, Cd, and Hg were exceeded in some samples, but most had levels considered safe for human consumption. No international thresholds exist for the other elements under study.

Assessment of the geoavailability of trace elements from minerals in mine wastes: analytical techniques and assessment of selected copper minerals

USGS Publications Warehouse

Driscoll, Rhonda; Hageman, Phillip L.; Benzel, William M.; Diehl, Sharon F.; Adams, David T.; Morman, Suzette; Choate, LaDonna M.

2012-01-01

In this study, four randomly selected copper-bearing minerals were examined—azurite, malachite, bornite, and chalcopyrite. The objectives were to examine and enumerate the crystalline and chemical properties of each of the minerals, to determine which, if any, of the Cu-bearing minerals might adversely affect systems biota, and to provide a multi-procedure reference. Laboratory work included use of computational software for quantifying crystalline and amorphous material and optical and electron imaging instruments to model and project crystalline structures. Chemical weathering, human fluid, and enzyme simulation studies were also conducted. The analyses were conducted systematically: X-ray diffraction and microanalytical studies followed by a series of chemical, bio-leaching, and toxicity experiments.

Trace elements and radionuclides in palm oil, soil, water, and leaves from oil palm plantations: A review.

PubMed

Olafisoye, O B; Oguntibeju, O O; Osibote, O A

2017-05-03

Oil palm (Elaeisguineensis) is one of the most productive oil producing plant in the world. Crude palm oil is composed of triglycerides supplying the world's need of edible oils and fats. Palm oil also provides essential elements and antioxidants that are potential mediators of cellular functions. Experimental studies have demonstrated the toxicity of the accumulation of significant amounts of nonessential trace elements and radionuclides in palm oil that affects the health of consumers. It has been reported that uptake of trace elements and radionuclides from the oil palm tree may be from water and soil on the palm plantations. In the present review, an attempt was made to revise and access knowledge on the presence of some selected trace elements and radionuclides in palm oil, soil, water, and leaves from oil palm plantations based on the available facts and data. Existing reports show that the presence of nonessential trace elements and radionuclides in palm oil may be from natural or anthropogenic sources in the environment. However, the available literature is limited and further research need to be channeled to the investigation of trace elements and radionuclides in soil, water, leaves, and palm oil from oil palm plantations around the globe.

Acute toxicity and synergism of cadmium and zinc in white shrimp, Penaeus setiferus, Juveniles

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

Vanegas, C.; Espina, S.; Botello, A.V.

1997-01-01

Toxic effects of individual heavy metals on decapod crustaceans have been reported frequently, but little information exists concerning interactions. Among the non-essential heavy metals, cadmium is one of the most hazardous elements in the aquatic environment; on the other hand, zinc is an essential element, but toxic when present in greater than trace amounts. Biological effects of cadmium in aquatic organisms are complex due to the interactions with both environmental variables and other toxic agents. In decapod crustaceans, the toxicity of cadmium and zinc is modified by salinity, temperature, hypoxia, calcium ion concentrations and life-cycle stage. Heavy metal pollution hasmore » increased in the coastal waters of the Gulf of Mexico, particularly in shrimp habitat. This study examined the toxicity of cadmium and zinc to white shrimp juveniles and looked at the interaction of the metals. 16 refs., 2 tabs.« less

Toxic and essential mineral elements content of black tea leaves and their tea infusions consumed in Iran.

PubMed

Salahinejad, Maryam; Aflaki, Fereydoon

2010-04-01

The metal contents of eleven black tea samples, four cultivated in Iran and seven imported, and their tea infusions were determined. Twelve elements consisting toxic metals (Al, As, Pb, Cr, Cd, and Ni) and essential mineral elements (Fe, Zn, Cu, Mn, Ca, and Mg) were analyzed using inductively coupled plasma atomic emission spectroscopy (ICP-AES). Al, Ca, Mg, and Mn ranged in black tea leaves at mg g(-1) levels, while Cr, Fe, Ni, Cu, Zn were at microg g(-1) levels. Analysis of variance showed no statistically significant differences among most elements determined in cultivated and imported black teas in Iran except for Ni and Cu. The extraction efficiency of each element into tea infusions was evaluated. The solubility of measured metals in infusion extracts varied widely and ranged from 0 to 59.3%. Among the studied elements, Cr, Pb, and Cd showed the lowest rates of solubility and Ni had the highest rates of solubility. The amount of toxic metals and essential mineral elements that one may take up through consumption of black tea infusion was estimated. The amount of realizing each element into tea infusions and acceptable daily intake, for safety consumption of black tea, was compared.

Manganese toxicity upon overexposure

PubMed Central

Crossgrove, Janelle; Zheng, Wei

2014-01-01

Manganese (Mn) is a required element and a metabolic byproduct of the contrast agent mangafodipir trisodium (MnDPDP). The Mn released from MnDPDP is initially sequestered by the liver for first-pass elimination, which allows an enhanced contrast for diagnostic imaging. The administration of intravenous Mn impacts its homeostatic balance in the human body and can lead to toxicity. Human Mn deficiency has been reported in patients on parenteral nutrition and in micronutrient studies. Mn toxicity has been reported through occupational (e.g. welder) and dietary overexposure and is evidenced primarily in the central nervous system, although lung, cardiac, liver, reproductive and fetal toxicity have been noted. Mn neurotoxicity results from an accumulation of the metal in brain tissue and results in a progressive disorder of the extrapyramidal system which is similar to Parkinson's disease. In order for Mn to distribute from blood into brain tissue, it must cross either the blood–brain barrier (BBB) or the blood–cerebrospinal fluid barrier (BCB). Brain import, with no evidence of export, would lead to brain Mn accumulation and neurotoxicity. The mechanism for the neurodegenerative damage specific to select brain regions is not clearly understood. Disturbances in iron homeostasis and the valence state of Mn have been implicated as key factors in contributing to Mn toxicity. Chelation therapy with EDTA and supplementation with levodopa are the current treatment options, which are mildly and transiently efficacious. In conclusion, repeated administration of Mn, or compounds that readily release Mn, may increase the risk of Mn-induced toxicity. PMID:15617053

Bioaccumulation and toxicity of selenium compounds in the green alga Scenedesmus quadricauda

PubMed Central

Umysová, Dáša; Vítová, Milada; Doušková, Irena; Bišová, Kateřina; Hlavová, Monika; Čížková, Mária; Machát, Jiří; Doucha, Jiří; Zachleder, Vilém

2009-01-01

Background Selenium is a trace element performing important biological functions in many organisms including humans. It usually affects organisms in a strictly dosage-dependent manner being essential at low and toxic at higher concentrations. The impact of selenium on mammalian and land plant cells has been quite extensively studied. Information about algal cells is rare despite of the fact that they could produce selenium enriched biomass for biotechnology purposes. Results We studied the impact of selenium compounds on the green chlorococcal alga Scenedesmus quadricauda. Both the dose and chemical forms of Se were critical factors in the cellular response. Se toxicity increased in cultures grown under sulfur deficient conditions. We selected three strains of Scenedesmus quadricauda specifically resistant to high concentrations of inorganic selenium added as selenite (Na2SeO3) – strain SeIV, selenate (Na2SeO4) – strain SeVI or both – strain SeIV+VI. The total amount of Se and selenomethionine in biomass increased with increasing concentration of Se in the culturing media. The selenomethionine made up 30–40% of the total Se in biomass. In both the wild type and Se-resistant strains, the activity of thioredoxin reductase, increased rapidly in the presence of the form of selenium for which the given algal strain was not resistant. Conclusion The selenium effect on the green alga Scenedesmus quadricauda was not only dose dependent, but the chemical form of the element was also crucial. With sulfur deficiency, the selenium toxicity increases, indicating interference of Se with sulfur metabolism. The amount of selenium and SeMet in algal biomass was dependent on both the type of compound and its dose. The activity of thioredoxin reductase was affected by selenium treatment in dose-dependent and toxic-dependent manner. The findings implied that the increase in TR activity in algal cells was a stress response to selenium cytotoxicity. Our study provides a new insight into the impact of selenium on green algae, especially with regard to its toxicity and bioaccumulation. PMID:19445666

Major Limitations in Using Element Concentrations in Hair as Biomarkers of Exposure to Toxic and Essential Trace Elements in Children

PubMed Central

Skröder, Helena; Kippler, Maria; Nermell, Barbro; Tofail, Fahmida; Levi, Michael; Rahman, Syed Moshfiqur; Raqib, Rubhana

2017-01-01

Background: Hair is a commonly used exposure biomarker for metals and other trace elements, but concern has been raised regarding its appropriateness for assessing the internal dose. Objectives: The aim of the present study was to evaluate children’s hair as biomarker of internal dose for toxic (As, Mn, Cd, Pb) and essential elements (Mg, Ca, Fe, Co, Cu, Zn, Se, Mo). Methods: In 207 children (9–10 years of age), originating from a population-based cohort in rural Bangladesh, we measured concentrations of the selected elements in hair (2cm closest to the scalp) using ICP-MS. We compared these with previously measured concentrations in erythrocytes, urine, and water. For a subset of children (n=19), we analyzed four consecutive 2cm pieces of hair. Results: There were strong associations between hair As and the other biomarkers (erythrocytes: rS=0.73, p<0.001; urine: rS=0.66, p<0.001); and water (rS=0.60, p<0.001); and there were significant correlations between Se in hair and erythrocytes (overall rS=0.38, p<0.001), and urine (rS=0.29, p<0.001). Hair Co and Mo showed weak correlations with concentrations in erythrocytes. Hair Mn was not associated with Mn in erythrocytes, urine, or water, and the geometric mean concentration increased almost five times from the 2cm closest to the head to the 7th–8th cm (p<0.001). Also Mg, Ca, Co, Cd, and Pb increased from the scalp outward (>50% higher in 7th–8th cm compared with 1st–2nd cm, p<0.001). Conclusions: Hair was found to be a useful exposure biomarker of absorbed As and Se only. Of all measured elements, hair Mn seemed the least reflective of internal dose. https://doi.org/10.1289/EHP1239 PMID:28669939

Arsenic toxicity in the human nerve cell line SK-N-SH in the presence of chromium and copper

PubMed Central

HU, LIGANG; GREER, JUSTIN B.; SOLO-GABRIELE, HELENA; FIEBER, LYNNE A.; CAI, YONG

2013-01-01

As, Cr, and Cu represent one potential combination of multiple metals/metalloids exposures since these three elements are simultaneously leached from chromated copper arsenate (CCA)-treated wood, a common product used for building construction, at levels that can be potentially harmful. This study investigated the neurotoxicity of As associated with CCA-treated wood when accompanied by Cr and Cu. The toxicity was evaluated on basis of a cytotoxicity model using human neuroblastoma cell line SK-N-SH. The cells were cultured with CCA-treated wood leachates or with solutions containing arsenate [As(V)], divalent copper [Cu(II)], trivalent chromium [Cr(III)] alone or in different combinations of the three elements. The toxicity was evaluated using variations in cell replication compared to controls after 96 hrs exposure. Among the three elements present in wood leachates, As played the primary role in the observed toxic effects, which exerted through multiple pathways, including the generation of oxidative stress. DOM affected the absorption of metals/metalloids into the test cells, which however did not obviously appear to impact toxicity. As toxicity was enhanced by Cu(II) and inhibited by Cr(III) at concentrations below U.S. EPA’s allowable maximum contaminant levels in drinking waters. Thus assessing As toxicity in real environments is not sufficient if based solely on the result from As. PMID:23473430

Abnormal chemical element concentrations in lichens of Isle Royale National Park

USGS Publications Warehouse

Bennett, J.P.

1995-01-01

Lichens have been used for many years to monitor changes in deposited airborne chemical elements in many areas, but few studies have focused on areas suspected of experiencing slightly elevated pollution. Detection of subtle patterns of slightly elevated pollutants calls for developing several lines of evidence as opposed to single line studies used in heavily polluted areas. This study of two lichen species, Hypogymnia physodes and Evernia mesomorpha, in Isle Royale National Park, Michigan compares the concentrations and ranks of elements with the concentrations and ranks of the elements in the earth's crust, changes in element concentrations over a nine year period, and the geography of element concentrations in the park. S, Zn, Pb, Cd and Se were elevated in both species and higher in rank compared to the concentrations and ranks in the earth's crust. Toxic elements increased 123% in Hypogymnia and 62% in Evernia over 9 years, compared to increases of 45% and 59% for non-toxic elements in each species, respectively. Geographically, the lichens at certain localities with higher exposures experienced higher than average element concentrations. Finally, tissue concentrations of Mn, S and Se at some localities were above levels known to be either toxic or similar to those found in polluted areas. These four lines of evidence suggest that Isle Royale National Park is experiencing the onset of chronic air pollution stress from a number of sources.

Selenium uptake through cystine transporter mediated by glutathione conjugation.

PubMed

Tobe, Takao; Ueda, Koji; Aoki, Akira; Okamoto, Yoshinori; Kojima, Nakao; Jinno, Hideto

2017-01-01

Selenium (Se) is an essential trace element and is regarded as a protective agent against cancer. In particular, antioxidant effects of selenoenzymes contribute to cancer prevention. Se can also produce reactive oxygen species and, thereby, exert cancer-selective cytotoxicity. Selenodiglutathione (SDG) is a primary Se metabolite conjugated to two glutathione (GSH) moieties. SDG increases intracellular Se accumulation and is more toxic than selenous acid (H 2 SeO 3 ), but the mechanisms for importing Se compounds into cells are not fully understood. Here, we propose a novel mechanism for importing Se, in the form of SDG. Cellular intake of Se compounds was assessed based on Se accumulation, as detected by ICP-MS. SDG incorporation was decreased in the presence of thiols (GSH, cysteine or their oxidized forms, GSSG and cystine), whereas H 2 SeO 3 uptake was increased by addition of GSH or cysteine. Cellular SDG uptake was decreased by pretreatment with specific inhibitors against gamma-glutamyl transpeptidase (GGT) or the cystine/glutamate antiporter (system x c - ). Furthermore, siRNA against xCT, which is the light chain component of system x c - , significantly decreased SDG incorporation. These data suggest an involvement of SDG in Se incorporation, with SDG processed at the cell surface by GGT, leading to formation of selenodicysteine which, in turn, is likely to be imported via xCT. Because GGT and xCT are highly expressed in cancer cells, these mechanisms mediated by the cystine transporter might underlie the cancer-selective toxicity of Se. In addition, the system described in our study appears to represent a physiological transport mechanism for the essential element Se.

Fluorescent bioassays for toxic metals in milk and yoghurt

PubMed Central

2012-01-01

Background From a human health viewpoint, contaminated milk and its products could be a source of long-term exposure to toxic metals. Simple, inexpensive, and on-site assays would enable constant monitoring of their contents. Bioassays that can measure toxic metals in milk or yoghurt might reduce the risk. For this purpose, the green fluorescent protein (GFP)-tagged trans factors, ArsR-GFP and CadC-GFP, together with their cis elements were used to develop such bioassays. Results ArsR-GFP or CadC-GFP, which binds either toxic metal or DNA fragment including cis element, was directly mixed with cow’s milk or yoghurt within a neutral pH range. The fluorescence of GFP, which is reflected by the association/dissociation ratio between cis element and trans factor, significantly changed with increasing externally added As (III) or Cd (II) whereas smaller responses to externally added Pb (II) and Zn (II) were found. Preparation and dilution of whey fraction at low pH were essential to intrinsic zinc quantification using CadC-GFP. Using the extraction procedure and bioassay, intrinsic Zn (II) concentrations ranging from 1.4 to 4.8 mg/l for milk brands and from 1.2 to 2.9 mg/kg for yoghurt brands were determined, which correlated to those determined using inductively coupled plasma atomic emission spectroscopy. Conclusions GFP-tagged bacterial trans factors and cis elements can work in the neutralized whole composition and diluted whey fraction of milk and yoghurt. The feature of regulatory elements is advantageous for establishment of simple and rapid assays of toxic metals in dairy products. PMID:23098077

Fluorescent bioassays for toxic metals in milk and yoghurt.

PubMed

Siddiki, Mohammad Shohel Rana; Ueda, Shunsaku; Maeda, Isamu

2012-10-25

From a human health viewpoint, contaminated milk and its products could be a source of long-term exposure to toxic metals. Simple, inexpensive, and on-site assays would enable constant monitoring of their contents. Bioassays that can measure toxic metals in milk or yoghurt might reduce the risk. For this purpose, the green fluorescent protein (GFP)-tagged trans factors, ArsR-GFP and CadC-GFP, together with their cis elements were used to develop such bioassays. ArsR-GFP or CadC-GFP, which binds either toxic metal or DNA fragment including cis element, was directly mixed with cow's milk or yoghurt within a neutral pH range. The fluorescence of GFP, which is reflected by the association/dissociation ratio between cis element and trans factor, significantly changed with increasing externally added As (III) or Cd (II) whereas smaller responses to externally added Pb (II) and Zn (II) were found. Preparation and dilution of whey fraction at low pH were essential to intrinsic zinc quantification using CadC-GFP. Using the extraction procedure and bioassay, intrinsic Zn (II) concentrations ranging from 1.4 to 4.8 mg/l for milk brands and from 1.2 to 2.9 mg/kg for yoghurt brands were determined, which correlated to those determined using inductively coupled plasma atomic emission spectroscopy. GFP-tagged bacterial trans factors and cis elements can work in the neutralized whole composition and diluted whey fraction of milk and yoghurt. The feature of regulatory elements is advantageous for establishment of simple and rapid assays of toxic metals in dairy products.

Development, validation and application of an ICP-MS/MS method to quantify minerals and (ultra-)trace elements in human serum.

PubMed

Meyer, Sören; Markova, Mariya; Pohl, Gabriele; Marschall, Talke A; Pivovarova, Olga; Pfeiffer, Andreas F H; Schwerdtle, Tanja

2018-09-01

Multi-element determination in human samples is very challenging. Especially in human intervention studies sample volumes are often limited to a few microliters and due to the high number of samples a high-throughput is indispensable. Here, we present a state-of-the-art ICP-MS/MS-based method for the analysis of essential (trace) elements, namely Mg, Ca, Fe, Cu, Zn, Mo, Se and I, as well as food-relevant toxic elements such as As and Cd. The developed method was validated regarding linearity of the calibration curves, method LODs and LOQs, selectivity and trueness as well as precision. The established reliable method was applied to quantify the element serum concentrations of participants of a human intervention study (LeguAN). The participants received isocaloric diets, either rich in plant protein or in animal protein. While the serum concentrations of Mg and Mo increased in participants receiving the plant protein-based diet (above all legumes), the Se concentration in serum decreased. In contrast, the animal protein-based diet, rich in meat and dairy products, resulted in an increased Se concentration in serum. Copyright © 2018 Elsevier GmbH. All rights reserved.

Bacterial Cell Surface Adsorption of Rare Earth Elements

NASA Astrophysics Data System (ADS)

Jiao, Y.; Park, D.; Reed, D.; Fujita, Y.; Yung, M.; Anderko, A.; Eslamimanesh, A.

2015-12-01

Rare earth elements (REE) play a critical role in many emerging clean energy technologies, including high-power magnets, wind turbines, solar panels, hybrid/electric vehicle batteries and lamp phosphors. In order to sustain demand for such technologies given current domestic REE shortages, there is a need to develop new approaches for ore processing/refining and recycling of REE-containing materials. To this end, we have developed a microbially-mediated bioadsorption strategy with application towards enrichment of REE from complex mixtures. Specifically, the bacterium Caulobacter crescentus was genetically engineered to display lanthanide binding tags (LBTs), short peptides that possess high affinity and specificity for rare earth elements, on its cell surface S-layer protein. Under optimal conditions, LBT-displayed cells adsorbed greater than 5-fold more REE than control cells lacking LBTs. Competition binding experiments with a selection of REEs demonstrated that our engineered cells could facilitate separation of light- from heavy- REE. Importantly, binding of REE onto our engineered strains was much more favorable compared to non-REE metals. Finally, REE bound to the cell surface could be stripped off using citrate, providing an effective and non-toxic REE recovery method. Together, this data highlights the potential of our approach for selective REE enrichment from REE containing mixtures.

Physical, chemical, and biological data for detailed study of the Sun River Irrigation Project, Freezout Lake Wildlife Management Area, and Benton Lake National Wildlife Refuge, west-central Montana, 1990-92, with selected data for 1987-89

USGS Publications Warehouse

Lambing, J.H.; Nimick, D.A.; Knapton, J.R.; Palawski, D.U.

1994-01-01

Physical chemical, and biological data were collected in the lower Sun River area of west-central Montana during 1990-92 as part of a U.S. Department of the Interior detailed study of the extent, magnitude, sources, and potential biological impacts of contaminants associated with irrigation drainage. Physical and chemical data were collected from areas within and near the Sun River Irrigation Project and from wetland areas receiving irrigation drainage. Biological data were collected from areas in and near Freezout Lake Wildlife Management Area and Benton Lake National Wildlife Refuge. Additional biological data were collected previously during 1987-89 as part of a U.S. Fish and Wildlife Service program. This report presents data for selenium and other potentially toxic constituents in solid-phase, water, and biological media. Data consist of concentrations of major and trace elements in soil and drill cores; concen- trations of major ions, nutrients, and trace elements in ground water and surface water; and trace-element concentrations in bottom sediment and biological tissue. Hydrogeologic data for domestic and test wells and daily streamflow data for selected sites also are included.

A Challenging Case of Acute Mercury Toxicity

PubMed Central

Alghoula, Faysal; Holewinski, Christopher

2018-01-01

Background Mercury exists in multiple forms: elemental, organic, and inorganic. Its toxic manifestations depend on the type and magnitude of exposure. The role of colonoscopic decompression in acute mercury toxicity is still unclear. We present a case of acute elemental mercury toxicity secondary to mercury ingestion, which markedly improved with colonoscopic decompression. Clinical Case A 54-year-old male presented to the ED five days after ingesting five ounces (148 cubic centimeters) of elemental mercury. Examination was only significant for a distended abdomen. Labs showed elevated serum and urine mercury levels. An abdominal radiograph showed radiopaque material throughout the colon. Succimer and laxatives were initiated. The patient had recurrent bowel movements, and serial radiographs showed interval decrease of mercury in the descending colon with interval increase in the cecum and ascending colon. Colonoscopic decompression was done successfully. The colon was evacuated, and a repeat radiograph showed decreased hyperdense material in the colon. Three months later, a repeat radiograph showed no hyperdense material in the colon. Conclusion Ingested elemental mercury can be retained in the colon. Although there are no established guidelines for colonoscopic decompression, our patient showed significant improvement. We believe further studies on this subject are needed to guide management practices. PMID:29559996

Monitoring of toxic elements present in sludge of industrial waste using CF-LIBS.

PubMed

Kumar, Rohit; Rai, Awadhesh K; Alamelu, Devanathan; Aggarwal, Suresh K

2013-01-01

Industrial waste is one of the main causes of environmental pollution. Laser-induced breakdown spectroscopy (LIBS) was applied to detect the toxic metals in the sludge of industrial waste water. Sludge on filter paper was obtained after filtering the collected waste water samples from different sections of a water treatment plant situated in an industrial area of Kanpur City. The LIBS spectra of the sludge samples were recorded in the spectral range of 200 to 500 nm by focusing the laser light on sludge. Calibration-free laser-induced breakdown spectroscopy (CF-LIBS) technique was used for the quantitative measurement of toxic elements such as Cr and Pb present in the sample. We also used the traditional calibration curve approach to quantify these elements. The results obtained from CF-LIBS are in good agreement with the results from the calibration curve approach. Thus, our results demonstrate that CF-LIBS is an appropriate technique for quantitative analysis where reference/standard samples are not available to make the calibration curve. The results of the present experiment are alarming to the people living nearby areas of industrial activities, as the concentrations of toxic elements are quite high compared to the admissible limits of these substances.

Health and safety in the dental clinic - Hygiene regulations for use of elemental mercury in the protection of rights, safety and well-being of the patients, workers and the environment.

PubMed

Ngim, Chunhan; Ngim, Allister Daquan

2013-12-01

The rules governing the use of metallic mercury, a toxic and hazardous chemical, is in most jurisdictions identical to widely accepted standards and practices for handling the same chemical in industry for the protection of humans and their work environment. There cannot be exceptions solely for the practitioner dentists and their patients. Any workplace must be safe for both workers and visitors. The latter being dental patients waiting in the dentist's work environment. We reviewed the literature for toxic health effects of elemental mercury upon humans and present information about the Minimata Convention convened by the United Nations Environment Programme. A study conducted among dentists in Singapore and their personal work environment almost 30 years ago contributed to the workplace standard for elemental mercury, which was reduced, and is still currently enforced as a global standard. We recommend that dentists, with a large alternative battery of restorative materials today, make selection of a restorative material a more seriously considered choice, and not to make use of amalgam without the proper use of personal protective equipment for themselves (members of the dental operating team) and their patients, (amalgam traps and judicious monitoring of their workplace air quality). Mercury is ubiquitous in our presence due to human activities; any reduction in the dentists' workplace contributes to a global reduction. © 2013 Published by Elsevier (Singapore) Pte Ltd.

A selfish genetic element confers non-Mendelian inheritance in rice.

PubMed

Yu, Xiaowen; Zhao, Zhigang; Zheng, Xiaoming; Zhou, Jiawu; Kong, Weiyi; Wang, Peiran; Bai, Wenting; Zheng, Hai; Zhang, Huan; Li, Jing; Liu, Jiafan; Wang, Qiming; Zhang, Long; Liu, Kai; Yu, Yang; Guo, Xiuping; Wang, Jiulin; Lin, Qibing; Wu, Fuqing; Ren, Yulong; Zhu, Shanshan; Zhang, Xin; Cheng, Zhijun; Lei, Cailin; Liu, Shijia; Liu, Xi; Tian, Yunlu; Jiang, Ling; Ge, Song; Wu, Chuanyin; Tao, Dayun; Wang, Haiyang; Wan, Jianmin

2018-06-08

Selfish genetic elements are pervasive in eukaryote genomes, but their role remains controversial. We show that qHMS7 , a major quantitative genetic locus for hybrid male sterility between wild rice ( Oryza meridionalis ) and Asian cultivated rice ( O. sativa ), contains two tightly linked genes [ Open Reading Frame 2 ( ORF2 ) and ORF3 ]. ORF2 encodes a toxic genetic element that aborts pollen in a sporophytic manner, whereas ORF3 encodes an antidote that protects pollen in a gametophytic manner. Pollens lacking ORF3 are selectively eliminated, leading to segregation distortion in the progeny. Analysis of the genetic sequence suggests that ORF3 arose first, followed by gradual functionalization of ORF2 Furthermore, this toxin-antidote system may have promoted the differentiation and/or maintained the genome stability of wild and cultivated rice. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Screen-Printed Electrodes Modified with “Green” Metals for Electrochemical Stripping Analysis of Toxic Elements

PubMed Central

Economou, Anastasios

2018-01-01

This work reviews the field of screen-printed electrodes (SPEs) modified with “green” metals for electrochemical stripping analysis of toxic elements. Electrochemical stripping analysis has been established as a useful trace analysis technique offering many advantages compared to competing optical techniques. Although mercury has been the preferred electrode material for stripping analysis, the toxicity of mercury and the associated legal requirements in its use and disposal have prompted research towards the development of “green” metals as alternative electrode materials. When combined with the screen-printing technology, such environment-friendly metals can lead to disposable sensors for trace metal analysis with excellent operational characteristics. This review focuses on SPEs modified with Au, Bi, Sb, and Sn for stripping analysis of toxic elements. Different modification approaches (electroplating, bulk modification, use of metal precursors, microengineering techniques) are considered and representative applications are described. A developing related field, namely biosensing based on stripping analysis of metallic nanoprobe labels, is also briefly mentioned. PMID:29596391

Screen-Printed Electrodes Modified with "Green" Metals for Electrochemical Stripping Analysis of Toxic Elements.

PubMed

Economou, Anastasios

2018-03-29

This work reviews the field of screen-printed electrodes (SPEs) modified with "green" metals for electrochemical stripping analysis of toxic elements. Electrochemical stripping analysis has been established as a useful trace analysis technique offering many advantages compared to competing optical techniques. Although mercury has been the preferred electrode material for stripping analysis, the toxicity of mercury and the associated legal requirements in its use and disposal have prompted research towards the development of "green" metals as alternative electrode materials. When combined with the screen-printing technology, such environment-friendly metals can lead to disposable sensors for trace metal analysis with excellent operational characteristics. This review focuses on SPEs modified with Au, Bi, Sb, and Sn for stripping analysis of toxic elements. Different modification approaches (electroplating, bulk modification, use of metal precursors, microengineering techniques) are considered and representative applications are described. A developing related field, namely biosensing based on stripping analysis of metallic nanoprobe labels, is also briefly mentioned.

BioMetals: a historical and personal perspective.

PubMed

Silver, Simon

2011-06-01

Understanding of BioMetals developed basically from a starting point about 60 years ago to current mechanistic understanding of the biological behavior of many metal ions from protein structural and functional studies. Figure 1 shows a Biochemical Periodic Table, element by element, with requirements, roles and biochemistry of the specific ions indicated. With few exceptions, the biology is of the ions formed and not of the elemental state of each. Early BioMetals efforts defined nutritional growth needs for animals, plants and microbes for inorganic "macro-nutrients" such as magnesium, calcium, potassium, sodium, and phosphate and of "micronutrients" such as copper, iron, manganese and zinc. Surprises came early with regard to microbes, for example the finding that Escherichia coli (then and now the standard microbial model) grows happily in the apparent total absence of calcium, sodium, and chloride, which are certainly major animal nutrients. Some elements such as mercury and arsenic are never required by living cells, but are always toxic, often at very low levels. Therefore, the division into nutrient elements and toxic elements came soon. For most inorganic nutrients, excessive amounts can be toxic as well, for example for copper and iron.

Evidence of Coal-Fly-Ash Toxic Chemical Geoengineering in the Troposphere: Consequences for Public Health.

PubMed

Herndon, J Marvin

2015-08-11

The widespread, intentional and increasingly frequent chemical emplacement in the troposphere has gone unidentified and unremarked in the scientific literature for years. The author presents evidence that toxic coal combustion fly ash is the most likely aerosolized particulate sprayed by tanker-jets for geoengineering, weather-modification and climate-modification purposes and describes some of the multifold consequences on public health. Two methods are employed: (1) Comparison of 8 elements analyzed in rainwater, leached from aerosolized particulates, with corresponding elements leached into water from coal fly ash in published laboratory experiments, and (2) Comparison of 14 elements analyzed in dust collected outdoors on a high-efficiency particulate air (HEPA) filter with corresponding elements analyzed in un-leached coal fly ash material. The results show: (1) the assemblage of elements in rainwater and in the corresponding experimental leachate are essentially identical. At a 99% confidence interval, they have identical means (T-test) and identical variances (F-test); and (2) the assemblage of elements in the HEPA dust and in the corresponding average un-leached coal fly ash are likewise essentially identical. The consequences on public health are profound, including exposure to a variety of toxic heavy metals, radioactive elements, and neurologically-implicated chemically mobile aluminum released by body moisture in situ after inhalation or through transdermal induction.

Exploiting CRISPR-Cas to manipulate Enterococcus faecalis populations.

PubMed

Hullahalli, Karthik; Rodrigues, Marinelle; Palmer, Kelli L

2017-06-23

CRISPR-Cas provides a barrier to horizontal gene transfer in prokaryotes. It was previously observed that functional CRISPR-Cas systems are absent from multidrug-resistant (MDR) Enterococcus faecalis , which only possess an orphan CRISPR locus, termed CRISPR2, lacking cas genes. Here, we investigate how the interplay between CRISPR-Cas genome defense and antibiotic selection for mobile genetic elements shapes in vitro E. faecalis populations. We demonstrate that CRISPR2 can be reactivated for genome defense in MDR strains. Interestingly, we observe that E. faecalis transiently maintains CRISPR targets despite active CRISPR-Cas systems. Subsequently, if selection for the CRISPR target is present, toxic CRISPR spacers are lost over time, while in the absence of selection, CRISPR targets are lost over time. We find that forced maintenance of CRISPR targets induces a fitness cost that can be exploited to alter heterogeneous E. faecalis populations.

Trace elements in parenteral nutrition: a practical guide for dosage and monitoring for adult patients.

PubMed

Fessler, Theresa A

2013-12-01

Parenteral nutrition (PN) is a life-sustaining therapy for hundreds of thousands of people who have severe impairment of gastrointestinal function. Trace elements are a small but very important part of PN that can be overlooked during busy practice. Serious complications can result from trace element deficiencies and toxicities, and this is especially problematic during times of product shortages. Practical information on parenteral trace element use can be gleaned from case reports, some retrospective studies, and very few randomized controlled trials. A general knowledge of trace element metabolism and excretion, deficiency and toxicity symptoms, products, optimal dosages, and strategies for supplementation, restriction, and monitoring will equip practitioners to provide optimal care for their patients who depend on PN.

Trace-elements in sheep grazing near a lead-zinc smelting complex at Port Pirie, South Australia

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

Koh, T.S.; Judson, G.J.

1986-07-01

In South Australia, several studies have shown that heavy metal pollution of soils and plants occurs in the vicinity of a lead/zinc smelter at Port Pirie. Data on soil analysis indicates that at least 3400 km/sup 2/ of land near these smelters has been contaminated by the fallout of Pb, Zn and Cd. It is possible that contamination of soil and pasture by heavy metals may adversely affect the health of livestock grazing near the smelters. In sheep, Pb toxicity causes anorexia, abdominal pain and diarrhea while Zn or Cd supplementation reduces the Cu status. This study was undertaken tomore » investigate the effects of heavy metals on the trace-element status of sheep grazing at selected distances from the Port Pirie smelters.« less

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Sun River area, west-central Montana, 1986-87

USGS Publications Warehouse

Knapton, J.R.; Jones, W.E.; Sutphin, J.W.

1988-01-01

The Sun River area was selected for a reconnaissance investigation of irrigation drainage because sufficient information existed to indicate that potential problems of a toxic nature might exist. The area of study included the Sun River Irrigation Project, Freeze-out Lake Game Management Area, and Benton Lake National Wildlife Refuge. Water, bottom sediment , and biota were sampled at selected sites and analyzed for inorganic and organic constituents that could be toxic at large concentrations. Although selenium was of primary concern, other trace elements and selected pesticides were also analyzed. Some water quality problems have been prevalent for many years in the Sun River Irrigation Projects, including the Sun River and Muddy Creek. However, during this study, most sampling sites were free of concentrations of toxic constituents that are in excess of established criteria and standards. There was little change in arsenic, boron, mercury, and selenium concentrations in fish and invertebrates at Sun River sampling sites upstream and downstream from the irrigation project. Presently, the most serious threat within the irrigation project appears to be from nitrate in groundwater. Water from some wells contains nitrate concentration in excess of drinking water standards (10 mg/L) established for the State of Montana. The largest selenium concentrations in water and bottom sediment were from seeps that surround Benton Lake, with maximum concentrations of 580 mg/L in water and biological samples. Several eared-grebe livers from Freezeout Lake and several coot livers and eggs from Benton Lake had selenium concentrations indicative of contamination. (See also W89-07064) (Author 's abstract)

Natural and anthropic effects on hydrochemistry and major and trace elements in the water mass of a Spanish Pyrenean glacial lake set.

PubMed

Santolaria, Zoe; Arruebo, Tomás; Pardo, Alfonso; Rodríguez-Casals, Carlos; Matesanz, José María; Lanaja, Francisco Javier; Urieta, José Santiago

2017-07-01

This study presents the key hydrochemical characteristics and concentration levels of major (Ca, Mg, Na, Si, K, Sr, Fe) and trace (Ba, Sc, Cr, Mn, Al, As, Li, Co, Cu, U, Pb, Hg, Au, Sn, Zn, Cd, Ag, Ni) elements in the water mass of four selected Pyrenean cirque glacial lakes (Sabocos, Baños, Truchas and Escalar tarns) with different catchment features, between 2010 and 2013. Resulting data set is statistically analyzed to discriminate between the natural or anthropic origin of the elements. Analyses indicate that in all cases, the main source of most major and trace elements is geological weathering, being thus individual bedrock composition the main driver of differences between lakes. Several anthropogenic sources of airborne Cu, Sc, Co, and Cr must be also considered. The shallowness of the lake is also a factor that may influence element cycling and concentration levels in its water mass. Concentrations of anthropogenic elements were low, comparable to those reported in other glacial lakes, way below the WHO, US EPA, EC, and Spanish legal limits for drinking water quality, indicating the absence of serious pollution. Toxic heavy metals Cd, Pb, Hg, and Zn were not detected in any of the tarns.

Trace elements in agroecosystems and impacts on the environment.

PubMed

He, Zhenli L; Yang, Xiaoe E; Stoffella, Peter J

2005-01-01

Trace elements mean elements present at low concentrations (mg kg-1 or less) in agroecosystems. Some trace elements, including copper (Cu), zinc (Zn), manganese (Mn), iron (Fe), molybdenum (Mo), and boron (B) are essential to plant growth and are called micronutrients. Except for B, these elements are also heavy metals, and are toxic to plants at high concentrations. Some trace elements, such as cobalt (Co) and selenium (Se), are not essential to plant growth but are required by animals and human beings. Other trace elements such as cadmium (Cd), lead (Pb), chromium (Cr), nickel (Ni), mercury (Hg), and arsenic (As) have toxic effects on living organisms and are often considered as contaminants. Trace elements in an agroecosystem are either inherited from soil parent materials or inputs through human activities. Soil contamination with heavy metals and toxic elements due to parent materials or point sources often occurs in a limited area and is easy to identify. Repeated use of metal-enriched chemicals, fertilizers, and organic amendments such as sewage sludge as well as wastewater may cause contamination at a large scale. A good example is the increased concentration of Cu and Zn in soils under long-term production of citrus and other fruit crops. Many chemical processes are involved in the transformation of trace elements in soils, but precipitation-dissolution, adsorption-desorption, and complexation are the most important processes controlling bioavailability and mobility of trace elements in soils. Both deficiency and toxicity of trace elements occur in agroecosystems. Application of trace elements in fertilizers is effective in correcting micronutrient deficiencies for crop production, whereas remediation of soils contaminated with metals is still costly and difficult although phytoremediation appears promising as a cost-effective approach. Soil microorganisms are the first living organisms subjected to the impacts of metal contamination. Being responsive and sensitive, changes in microbial biomass, activity, and community structure as a result of increased metal concentration in soil may be used as indicators of soil contamination or soil environmental quality. Future research needs to focus on the balance of trace elements in an agroecosystem, elaboration of soil chemical and biochemical parameters that can be used to diagnose soil contamination with or deficiency in trace elements, and quantification of trace metal transport from an agroecosystem to the environment.

Critical evaluation of the ability of sequential extraction procedures to quantify discrete forms of selenium in sediments and soils.

PubMed

Wright, Michael T; Parker, David R; Amrhein, Christopher

2003-10-15

Sequential extraction procedures (SEPs) have been widely used to characterize the mobility, bioavailibility, and potential toxicity of trace elements in soils and sediments. Although oft-criticized, these methods may perform best with redox-labile elements (As, Hg, Se) for which more discrete biogeochemical phases may arise from variations in oxidation number. We critically evaluated two published SEPs for Se for their specificity and precision by applying them to four discrete components in an inert silica matrix: soluble Se(VI) (selenate), Se(IV) (selenite) adsorbed onto goethite, elemental Se, and a metal selenide (FeSe; achavalite). These were extracted both individually and in a mixed model sediment. The more selective of the two procedures was modified to further improve its selectivity (SEP 2M). Both SEP 1 and SEP 2M quantitatively recovered soluble selenate but yielded incomplete recoveries of adsorbed selenite (64% and 81%, respectively). SEP 1 utilizes 0.1 M K2S2O8 to target "organically associated" Se, but this extractant also solubilized most of the elemental (64%) and iron selenide (91%) components of the model sediment. In SEP 2M, the Na2SO3 used in step III is effective in extracting elemental Se but also extracted 17% of the Se from the iron selenide, such that the elemental fraction would be overestimated should both forms coexist. Application of SEP 2M to eight wetland sediments further suggested that the Na2SO3 in step III extracts some organically associated Se, so a NaOH extraction was inserted beforehand to yield a further modification, SEP 2OH. Results using this five-step procedure suggested that the four-step SEP 2M could overestimate elemental Se by as much as 43% due to solubilization of organic Se. Although still imperfect in its selectivity, SEP 20H may be the most suitable procedure for routine, accurate fractionation of Se in soils and sediments. However, the strong oxidant (NaOCl) used in the final step cannot distinguish between refractory organic forms of Se and pyritic Se that might form under sulfur-reducing conditions.

A review on the elemental contents of Pakistani medicinal plants: Implications for folk medicines.

PubMed

Aziz, Muhammad Abdul; Adnan, Muhammad; Begum, Shaheen; Azizullah, Azizullah; Nazir, Ruqia; Iram, Shazia

2016-07-21

Substantially, plants produce chemicals such as primary and secondary metabolites, which have significant applications in modern therapy. Indigenous people mostly rely on traditional medicines derived from medicinal plants. These plants have the capacity to absorb a variety of toxic elements. The ingestion of such plants for medicinal purpose can have imperative side effects. Hence, with regard to the toxicological consideration of medicinal plants, an effort has been made to review the elemental contents of ethno medicinally important plants of Pakistan and to highlight the existing gaps in knowledge of the safety and efficacy of traditional herbal medications. Literature related to the elemental contents of ethno medicinal plants was acquired by utilizing electronic databases. We reviewed only macro-elemental and trace elemental contents of 69 medicinal plant taxa, which are traditionally used in Pakistan for the treatment of sundry ailments, including anemia, jaundice, cancer, piles, diarrhea, dysentery, headache, diabetes, asthma, blood purification, sedative and ulcer. A majority of plants showed elemental contents above the permissible levels as recommended by the World health organization (WHO). As an example, the concentrations of Cadmium (Cd) and Lead (Pb) were reportedly found higher than the WHO permissible levels in 43 and 42 medicinal plants, respectively. More specifically, the concentrations of Pb (54ppm: Silybum marianum) and Cd (5.25ppm: Artemisia herba-alba) were found highest in the Asteraceae family. The reported medicinal plants contain a higher amount of trace and toxic elements. Intake of these plants as traditional medicines may trigger the accumulation of trace and toxic elements in human bodies, which can cause different types of diseases. Thus, a clear understanding about the nature of toxic substances and factors affecting their concentrations in traditional medicines are essential prerequisites for efficacious herbal therapeutics with lesser or no side effects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The effects of trace element content on pyrite oxidation rates

NASA Astrophysics Data System (ADS)

Gregory, D. D.; Lyons, T.; Cliff, J. B.; Perea, D. E.; Johnson, A.; Romaniello, S. J.; Large, R. R.

2017-12-01

Pyrite acts as both an important source and sink for many different metals and metalloids in the environment, including many that are toxic. Oxidation of pyrite can release these elements while at the same time producing significant amounts of sulfuric acid. Such issues are common in the vicinity of abandoned mines and smelters, but, as pyrite is a common accessory mineral in many different lithologies, significant pyrite oxidation can occur whenever pyritic rocks are exposed to oxygenated water or the atmosphere. Accelerated exposure to oxygen can occur during deforestation, fracking for petroleum, and construction projects. Geochemical models for pyrite oxidation can help us develop strategies to mitigate these deleterious effects. An important component of these models is an accurate pyrite oxidation rate; however, current pyrite oxidation rates have been determined using relatively pure pyrite. Natural pyrite is rarely pure and has a wide range of trace element concentrations that may affect the oxidation rate. Furthermore, the position of trace elements within the mineral lattice can also affect the oxidation rate. For example, elements such as Ni and Co, which substitute into the pyrite lattice, are thought to stabilize the lattice and thus prevent pyrite oxidation. Alternatively, trace elements that are held within inclusions of other minerals could form a galvanic cell with the surrounding pyrite, thus enhancing pyrite oxidation rates. In this study, we present preliminary analyses from three different pyrite oxidation experiments each using natural pyrite with different trace element compositions. These results show that the pyrite with the highest trace element concentration has approximately an order of magnitude higher oxidation rate compared to the lowest trace element sample. To further elucidate the mechanisms, we employed microanalytical techniques to investigate how the trace elements are held within the pyrite. LA-ICPMS was used to determine the variability of trace element content from the pyrite samples. These data were then used to select areas of interest for NanoSIMS analyses, which in turn was used to select areas for TEM and APT. These analyses show that the trace element content of pyrite can be highly variable, which may significantly affect the rate of pyrite oxidation.

Objective Assessment of an Ionic Footbath (IonCleanse): Testing Its Ability to Remove Potentially Toxic Elements from the Body

PubMed Central

Kennedy, Deborah A.; Cooley, Kieran; Einarson, Thomas R.; Seely, Dugald

2012-01-01

Ionic footbaths are often used in holistic health centres and spas to aid in detoxification; however, claims that these machines eliminate toxins from the body have not been rigorously evaluated. In this proof-of-principle study, we sought to measure the release of potentially toxic elements from ionic footbaths into distilled and tap water with and without feet. Water samples were collected and analyzed following 30-minute ionic footbath sessions without feet using both distilled (n = 1) and tap water (n = 6) and following four ionic footbaths using tap water (once/week for 4 weeks) in six healthy participants. Urine collection samples were analyzed at four points during the study. Hair samples were analyzed for element concentrations at baseline and study conclusion. Contrary to claims made for the machine, there does not appear to be any specific induction of toxic element release through the feet when running the machine according to specifications. PMID:22174728

Llama-derived single domain antibodies specific for Abrus agglutinin.

PubMed

Goldman, Ellen R; Anderson, George P; Zabetakis, Dan; Walper, Scott; Liu, Jinny L; Bernstein, Rachael; Calm, Alena; Carney, James P; O'Brien, Thomas W; Walker, Jennifer L; Garber, Eric A E

2011-11-01

Llama derived single domain antibodies (sdAb), the recombinantly expressed variable heavy domains from the unique heavy-chain only antibodies of camelids, were isolated from a library derived from llamas immunized with a commercial abrin toxoid preparation. Abrin is a potent toxin similar to ricin in structure, sequence and mechanism of action. The selected sdAb were evaluated for their ability to bind to commercial abrin as well as abrax (a recombinant abrin A-chain), purified abrin fractions, Abrus agglutinin (a protein related to abrin but with lower toxicity), ricin, and unrelated proteins. Isolated sdAb were also evaluated for their ability to refold after heat denaturation and ability to be used in sandwich assays as both capture and reporter elements. The best binders were specific for the Abrus agglutinin, showing minimal binding to purified abrin fractions or unrelated proteins. These binders had sub nM affinities and regained most of their secondary structure after heating to 95 °C. They functioned well in sandwich assays. Through gel analysis and the behavior of anti-abrin monoclonal antibodies, we determined that the commercial toxoid preparation used for the original immunizations contained a high percentage of Abrus agglutinin, explaining the selection of Abrus agglutinin binders. Used in conjunction with anti-abrin monoclonal and polyclonal antibodies, these reagents can fill a role to discriminate between the highly toxic abrin and the related, but much less toxic, Abrus agglutinin and distinguish between different crude preparations.

Llama-Derived Single Domain Antibodies Specific for Abrus Agglutinin

PubMed Central

Goldman, Ellen R.; Anderson, George P.; Zabetakis, Dan; Walper, Scott; Liu, Jinny L.; Bernstein, Rachael; Calm, Alena; Carney, James P.; O’Brien, Thomas W.; Walker, Jennifer L.; Garber, Eric A. E.

2011-01-01

Llama derived single domain antibodies (sdAb), the recombinantly expressed variable heavy domains from the unique heavy-chain only antibodies of camelids, were isolated from a library derived from llamas immunized with a commercial abrin toxoid preparation. Abrin is a potent toxin similar to ricin in structure, sequence and mechanism of action. The selected sdAb were evaluated for their ability to bind to commercial abrin as well as abrax (a recombinant abrin A-chain), purified abrin fractions, Abrus agglutinin (a protein related to abrin but with lower toxicity), ricin, and unrelated proteins. Isolated sdAb were also evaluated for their ability to refold after heat denaturation and ability to be used in sandwich assays as both capture and reporter elements. The best binders were specific for the Abrus agglutinin, showing minimal binding to purified abrin fractions or unrelated proteins. These binders had sub nM affinities and regained most of their secondary structure after heating to 95 °C. They functioned well in sandwich assays. Through gel analysis and the behavior of anti-abrin monoclonal antibodies, we determined that the commercial toxoid preparation used for the original immunizations contained a high percentage of Abrus agglutinin, explaining the selection of Abrus agglutinin binders. Used in conjunction with anti-abrin monoclonal and polyclonal antibodies, these reagents can fill a role to discriminate between the highly toxic abrin and the related, but much less toxic, Abrus agglutinin and distinguish between different crude preparations. PMID:22174977

Historical Fluxes of Toxic Trace Elements and Associated Implications in the Salton Sea Basin

NASA Astrophysics Data System (ADS)

Odigie, K. O.; Hardisty, D. S.; Geraci, J. B.; Lyons, T. W.

2017-12-01

The Salton Sea is a polymictic, hypersaline lake that is predominantly sustained by wastewater and agricultural runoff from Mexico and the United States. It is a terminal lake that acts as a net sink for toxicants, which in addition to nutrients and increasing salinity, have dramatically transformed the lake over the past century. However, the impacts of these changes on the cycling and bio-accessibility of toxic elements and compounds and their associated human and environmental health implications are not well understood. This project aims to measure and model the fluxes of toxic elements, including selenium, lead, and mercury, in the lake over temporal and spatial scales by using geochemical data from the analysis of sediment cores, a pervasive salt crust, and the water column. The project also aims to elucidate the bio-accessibility and depositional environments of these elements. Preliminary results highlight two different oxygen concentration regimes in the lake: an increasingly anoxic condition in the bottom of the northern lobe and a seasonally variable oxygen deficiency in the bottom of the southern lobe. The deteriorating conditions at the lake could be exacerbated by a receding shoreline, which has already exposed several square kilometres of lake bed and is expected to continue as future inflows are diverted under the Quantification Settlement Agreement. Continued water conservation by Imperial Valley farmers and the increasing reuse of reclaimed water by Mexico are also expected to contribute to reduced inflows to the lake. Therefore, improved understanding of the cycling of toxic elements and their potential remobilization, including via wind entrainment (dust) associated with lake desiccation, will be valuable in protecting human and environmental health within the Salton Sea basin.

Modeling Aquatic Toxicity through Chromatographic Systems.

PubMed

Fernández-Pumarega, Alejandro; Amézqueta, Susana; Farré, Sandra; Muñoz-Pascual, Laura; Abraham, Michael H; Fuguet, Elisabet; Rosés, Martí

2017-08-01

Environmental risk assessment requires information about the toxicity of the growing number of chemical products coming from different origins that can contaminate water and become toxicants to aquatic species or other living beings via the trophic chain. Direct toxicity measurements using sensitive aquatic species can be carried out but they may become expensive and ethically questionable. Literature refers to the use of chromatographic measurements that correlate to the toxic effect of a compound over a specific aquatic species as an alternative to get toxicity information. In this work, we have studied the similarity in the response of the toxicity to different species and we have selected eight representative aquatic species (including tadpoles, fish, water fleas, protozoan, and bacteria) with known nonspecific toxicity to chemical substances. Next, we have selected four chromatographic systems offering good perspectives for surrogation of the eight selected aquatic systems, and thus prediction of toxicity from the chromatographic measurement. Then toxicity has been correlated to the chromatographic retention factor. Satisfactory correlation results have been obtained to emulate toxicity in five of the selected aquatic species through some of the chromatographic systems. Other aquatic species with similar characteristics to these five representative ones could also be emulated by using the same chromatographic systems. The final aim of this study is to model chemical products toxicity to aquatic species by means of chromatographic systems to reduce in vivo testing.

Spatial/Temporal Variations of Elemental Carbon, Organic Carbon, and Trace Elements in PM10 and the Impact of Land-Use Patterns on Community Air Pollution in Paterson, NJ

PubMed Central

Yu, Chang Ho; Fan, Zhi-Hua; Meng, Qingyu; Zhu, Xianlei; Korn, Leo; Bonanno, Linda J.

2014-01-01

An urban community PM10 (particulate matter ≤ 10 μm in aerodynamic diameter) air pollution study was conducted in Paterson, NJ, a mixed land-use community that is interspersed with industrial, commercial, mobile, and residential land-use types. This paper examines (1) the spatial/temporal variation of PM10, elemental carbon (EC), organic carbon (OC), and nine elements; and (2) the impact of land-use type on those variations. Air samples were collected from three community-oriented locations in Paterson that attempted to capture industrial, commercial, and mobile source-dominated emissions. Sampling was conducted for 24 hr every 6 days from November 2005 through December 2006. Samples were concurrently collected at the New Jersey Department of Environmental Protection-designated air toxics background site in Chester, NJ. PM10 mass, EC, OC, and nine elements (Ca, Cu, Fe, Pb, Mn, Ni, S, Ti, and Zn) that had more than 50% of samples above detection and known sources or are toxic were selected for spatial/temporal analysis in this study. The concentrations of PM10, EC, OC, and eight elements (except S) were significantly higher in Paterson than in Chester (P < 0.05). The concentrations of these elements measured in Paterson were also found to be higher during winter than the other three seasons (except S), and higher on weekdays than on weekends (except Pb). The concentrations of EC, Cu, Fe, and Zn at the commercial site in Paterson were significantly higher than the industrial and mobile sites; however, the other eight species were not significantly different within the city (P > 0.05). These results indicated that anthropogenic sources of air pollution were present in Paterson. The source apportionment confirmed the impact of vehicular and industrial emissions on the PM10 ambient air pollution in Paterson. The multiple linear regression analysis showed that categorical land-use type was a significant predictor for all air pollution levels, explaining up to 42% of the variability in concentration by land-use type only. PMID:21751583

The Effect of Toxic Leadership

DTIC Science & Technology

2012-03-15

traits) and not the disease (culture, climate, outcomes ).3 Several researchers agree that the long-term negative effect that toxic leaders have on an...The Effect of Toxic Leadership by Lieutenant Colonel Darrell W. Aubrey United States Army United States Army War...The Effect of Toxic Leadership 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Lieutenant

[The elemental composition of teeth hard tissues depending on the state of the environment].

PubMed

Suladze, N; Shishniashvili, T; Margvelashvili, V; Kobakhidze, K

2014-01-01

At present, great attention is paid to the origin of man-made micro elemental anomalies. To monitor the state of the environment and its effects on the human body, of great importance is the determination of the amount and distribution of various chemical elements in the dentin and enamel of the teeth. To determine the essential (Ca, Zn, Mn, Ni), conditionally essential (Rb, Ni, Sr) and toxic (Pb, Hg) trace elements in the mineralized tissues of the teeth and to identify the relationship between the elemental composition of the tooth structure and the state of the general and dental health depending on the state of the environment, we have examined 29 children aged 3-4 years who have carried out analysis of hard tissue of teeth (teeth used for remote medical reasons) for the maintenance of nine chemical elements. Children living in a relatively environmentally favorable conditions essential value and conditionally essential elements in the mineralized tissues of the teeth were within normal limits, and toxic elements slightly increased limits that differ from those of children living in environmentally disadvantaged areas. In particular, these essential elements were significantly reduced (except for zinc), as indicators of toxic elements - mercury and lead, increased by 12.5% and 44.5%, respectively, which is clearly reflected on the state of dental health because noted decompensated form of tooth decay. Thus, deviations in a state of general and dental health of children associated with an imbalance of macro-and microelements in the mineralized tissues of the teeth.

ELEMENTAL ANALYSIS OF RESPIRABLE TIRE PARTICLES AND ASSESSMENT OF CARDIO-PULMONARY TOXICITY IN RATS

EPA Science Inventory

Elemental Analysis of Respirable Tire Particles and Assessment of Cardio-pulmonary Toxicity in Rats

R.R. Gottipolu, PhD1, E. Landa, PhD2, J.K. McGee, MS1, M.C. Schladweiler, BS1, J.G. Wallenborn, MS3, A.D. Ledbetter, BS1, J.E. Richards, MS1 and U.P. Kodavanti, PhD1. 1NHEER...

Evaluation of the Biotoxicity of Tree Wood Ashes in Zebrafish Embryos.

PubMed

Consigli, Veronica; Guarienti, Michela; Bilo, Fabjola; Benassi, Laura; Depero, Laura E; Bontempi, Elza; Presta, Marco

2016-10-01

Ashes derived from biomass combustion and used as soil fertilizers can generate negative environmental and human health risks, related to leaching of heavy metals and other putative toxic elements. Tree wood ash composition may vary depending on geographical location and surrounding industrial processes. In this study, we evaluated the biotoxicity of lixiviated tree wood ash samples from trees of the Ash (Fraxinus), Cherry (Pronus), Hazel (Corylus), and Black locust (Robinia) genus collected in an industrialized region in Northern Italy. Elemental chemical analysis of the samples was performed by total reflection X-ray fluorescence technique and their biotoxicity was assessed in zebrafish (Danio rerio) embryos. Ashes from Ash, Cherry, and Hazel trees, but not Black locust trees, had a high concentration of heavy metals and other putative toxic elements. Accordingly, a dose-dependent increase in mortality rate and morphological and teratogenic defects was observed in zebrafish embryos treated with lixiviated Ash, Cherry, and Hazel tree wood samples, whereas the toxicity of Black locust tree wood ashes was negligible. In conclusion, lixiviated wood ashes from different plants show a different content of toxic elements that correlate with their biotoxic effects on zebrafish embryos. Tree wood ashes derived from biomass combustion may represent a potential risk for the environment and human health.

Evidence of Coal-Fly-Ash Toxic Chemical Geoengineering in the Troposphere: Consequences for Public Health

PubMed Central

Herndon, J. Marvin

2015-01-01

The widespread, intentional and increasingly frequent chemical emplacement in the troposphere has gone unidentified and unremarked in the scientific literature for years. The author presents evidence that toxic coal combustion fly ash is the most likely aerosolized particulate sprayed by tanker-jets for geoengineering, weather-modification and climate-modification purposes and describes some of the multifold consequences on public health. Two methods are employed: (1) Comparison of 8 elements analyzed in rainwater, leached from aerosolized particulates, with corresponding elements leached into water from coal fly ash in published laboratory experiments, and (2) Comparison of 14 elements analyzed in dust collected outdoors on a high-efficiency particulate air (HEPA) filter with corresponding elements analyzed in un-leached coal fly ash material. The results show: (1) the assemblage of elements in rainwater and in the corresponding experimental leachate are essentially identical. At a 99% confidence interval, they have identical means (T-test) and identical variances (F-test); and (2) the assemblage of elements in the HEPA dust and in the corresponding average un-leached coal fly ash are likewise essentially identical. The consequences on public health are profound, including exposure to a variety of toxic heavy metals, radioactive elements, and neurologically-implicated chemically mobile aluminum released by body moisture in situ after inhalation or through transdermal induction. PMID:26270671

Evaluation of dietary exposure to minerals, trace elements and heavy metals from the muscle tissue of the lionfish Pterois volitans (Linnaeus 1758).

PubMed

Hoo Fung, Leslie A; Antoine, Johann M R; Grant, Charles N; Buddo, Dayne St A

2013-10-01

Twenty-five samples of Pterois volitans caught in Jamaican waters were analyzed for 25 essential, non-essential and toxic elements using Graphite Furnace Atomic Absorption Spectrophotometry (GF-AAS), Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) and Instrumental Neutron Activation Analysis (INAA). The mean values for calcium (355 mg/kg), copper (107 μg/kg), iron (0.81 mg/kg), potassium (3481 mg/kg), magnesium (322 mg/kg), manganese (0.04 mg/kg), selenium (0.47 mg/kg), sodium (700 mg/kg) and zinc (4.46 mg/kg) were used to estimate dietary intake. The percentage contribution to provisional tolerable weekly intake for a 70 kg male and a 65 kg female were also estimated for the toxic elements arsenic (1.28% M, 1.38% F), cadmium (0.26% M. 0.28% F), mercury (3.85% M, 4.15% F) and lead (0.17% M, 0.18% F). To further assess the risk of mercury toxicity and the role of mitigation provided by selenium, selenium-mercury molar ratios were calculated for all samples. All samples were shown to have a molar excess of selenium. In addition the suggested selenium health benefit value was calculated, and was positive for all samples. It was concluded that P. volitans appears to contribute modestly to mineral and trace element nutrition, while not being a significant contributor to dietary exposure of toxic elements. Copyright © 2013 Elsevier Ltd. All rights reserved.

The long (LINEs) and the short (SINEs) of it: altered methylation as a precursor to toxicity.

PubMed

Carnell, Ammie N; Goodman, Jay I

2003-10-01

Although once thought of as "junk" DNA, the importance of interspersed elements in the genome has become increasingly appreciated in recent years. In a broad sense these are collectively referred to as transposable elements, which encompass both transposons and retrotransposons. The latter include long interspersed nuclear elements (LINEs) and short interspersed nuclear elements (SINEs). Expression of these elements leads to genetic instability. Therefore, it is important that they remain transcriptionally silenced, and DNA methylation plays a key role in this regard. A framework for understanding the possible interplay between altered DNA methylation, an epigenetic change, and mutational events is presented. A case is made as to how retrotransposable elements, specifically LINEs and SINEs, are likely to emerge as key players in furthering our understanding of mechanisms underlying a variety of toxicities, including carcinogenesis but not limited to this endpoint.

Essential and toxic elements in commercial baby food on the Spanish and Serbian market.

PubMed

Škrbić, Biljana; Živančev, Jelena; Jovanović, Grigorije; Farre, Marinella

2017-03-01

About 10 heavy elements were determined in 90 samples of baby food collected from Spanish and Serbian market. The results indicated that iron, manganese and copper were most frequently detected. Tin was the predominant toxic element in both Spanish and Serbian samples, with occurrence frequencies of 12.5% and 10.0%, respectively. Element intake for Spanish and Serbian infants were estimated and compared with the recommended reference values, for the majority of elements being lower than one. However, iron and manganese intake through consumption of infant/follow-on formulas were assessed to be higher than the respective daily intakes. Particular attention should be paid to the exposure of infants who consume porridges made of vegetables and fish or chicken, because they may ingest certain elements, particularly arsenic and lead, at levels that exceed the reference toxicological values. Principal component analysis (PCA) was applied to classify and distinguish the different types of baby food.

Strategies for the engineered phytoremediation of toxic element pollution: mercury and arsenic.

PubMed

Meagher, Richard B; Heaton, Andrew C P

2005-12-01

Plants have many natural properties that make them ideally suited to clean up polluted soil, water, and air, in a process called phytoremediation. We are in the early stages of testing genetic engineering-based phytoremediation strategies for elemental pollutants like mercury and arsenic using the model plant Arabidopsis. The long-term goal is to develop and test vigorous, field-adapted plant species that can prevent elemental pollutants from entering the food-chain by extracting them to aboveground tissues, where they can be managed. To achieve this goal for arsenic and mercury, and pave the way for the remediation of other challenging elemental pollutants like lead or radionucleides, research and development on native hyperaccumulators and engineered model plants needs to proceed in at least eight focus areas: (1) Plant tolerance to toxic elementals is essential if plant roots are to penetrate and extract pollutants efficiently from heterogeneous contaminated soils. Only the roots of mercury- and arsenic-tolerant plants efficiently contact substrates heavily contaminated with these elements. (2) Plants alter their rhizosphere by secreting various enzymes and small molecules, and by adjusting pH in order to enhance extraction of both essential nutrients and toxic elements. Acidification favors greater mobility and uptake of mercury and arsenic. (3) Short distance transport systems for nutrients in roots and root hairs requires numerous endogenous transporters. It is likely that root plasma membrane transporters for iron, copper, zinc, and phosphate take up ionic mercuric ions and arsenate. (4) The electrochemical state and chemical speciation of elemental pollutants can enhance their mobility from roots up to shoots. Initial data suggest that elemental and ionic mercury and the oxyanion arsenate will be the most mobile species of these two toxic elements. (5) The long-distance transport of nutrients requires efficient xylem loading in roots, movement through the xylem up to leaves, and efficient xylem unloading aboveground. These systems can be enhanced for the movement of arsenic and mercury. (6) Aboveground control over the electrochemical state and chemical speciation of elemental pollutants will maximize their storage in leaves, stems, and vascular tissues. Our research suggests ionic Hg(II) and arsenite will be the best chemical species to trap aboveground. (7) Chemical sinks can increase the storage capacity for essential nutrients like iron, zinc, copper, sulfate, and phosphate. Organic acids and thiol-rich chelators are among the important chemical sinks that could trap maximal levels of mercury and arsenic aboveground. (8) Physical sinks such as subcellular vacuoles, epidermal trichome cells, and dead vascular elements have shown the evolutionary capacity to store large quantities of a few toxic pollutants aboveground in various native hyperaccumulators. Specific plant transporters may already recognize gluthione conjugates of Hg(II) or arsenite and pump them into vacuole.

Ionophore-based optical nanosensors incorporating hydrophobic carbon dots and a pH-sensitive quencher dye for sodium detection.

PubMed

Galyean, A A; Behr, M R; Cash, K J

2018-01-21

Nanosensors present a biological monitoring method that is biocompatible, reversible, and nano-scale, and they offer many advantages over traditional organic indicators. Typical ionophore-based nanosensors incorporate nile-blue derivative pH indicators but suffer from photobleaching while quantum dot alternatives pose a potential toxicity risk. In order to address this challenge, sodium selective nanosensors containing carbon dots and a pH-sensitive quencher molecule were developed based on an ion-exchange theory and a decoupled recognition element from the pH indicator. Carbon dots were synthesized and integrated into nanosensors containing a pH-indicator, an analyte-binding ligand (ionophore), and a charge-balancing additive. These nanosensors are ion-selective against potassium (selectivity coefficient of 0.4) and lithium (selectivity coefficient of 0.9). Reversible nanosensor response to sodium is also demonstrated. The carbon dot nanosensors are resistant to changes in optical properties for at least 12 h and display stable selectivity to physiologically-relevant sodium (alpha = 0.5 of 200 mM NaCl) for a minimum of 6 days.

Comparative assessment of button cells using a normalized index for potential pollution by heavy metals.

PubMed

Moreno-Merino, Luis; Jiménez-Hernández, Maria Emilia; de la Losa, Almudena; Huerta-Muñoz, Virginia

2015-09-01

Many household batteries worldwide still end up in landfills or are incinerated due to inefficient collection and recycling schemes. Toxic heavy metals from improperly discarded button cells pose a serious risk to human health and the environment, as they can pollute air, soil and water. This paper analyses a series of button cells selected from batteries available on the retail market, and compares their polluting potential. A total of 64 batteries were subjected to chemical analyses of 19 elements - including metals and metalloids - , and energy density measurements. The samples were from four different brands of each of the four most common button cell technologies (alkaline, zinc-air, silver oxide and lithium). An energy-normalized index - the Weighted Potential Pollution Index (WPPI) - was proposed to compare the polluting potential of the different batteries. The higher the battery WPPI score, the greater the content in toxic elements and the lower the energy output. The results of the chemical composition and energy density varied depending on the construction technology of the button cells. However, significant differences in both variables were also found when comparing different brands within the same technology. The differences in WPPI values confirmed the existence of a significant margin to reduce the environmental impact of discarded button cells simply by avoiding the most polluting options. The choice of the battery with the most favourable WPPI produced a reduction in potential pollution of 3-53% for silver oxide batteries, 4-39% for alkaline, 20-28% for zinc-air and 12-26% for lithium. Comparative potential pollution could be assessed when selecting batteries using an energy-normalized index such as WPPI to reduce the environmental impact of improperly disposed button cells. Published by Elsevier B.V.

Behavior as a common focus of toxicology and nutrition

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

Weiss, B.

1980-01-01

Behavior as an index of toxicity parallels its role as an index of nutritional impairment, just as toxicology and nutrition share other common themes. Intersections among the three disciplines arise because foodstuffs serve as one of the major routes of toxic exposure and also because food elements modify toxicity. With this perspective, the safety of our food supply is examined in the contexts of essential nutrients, toxins, toxic metals, manufactured contaminants, self-administered toxicants, and food additives.

Treatment of copper industry waste and production of sintered glass-ceramic.

PubMed

Coruh, Semra; Ergun, Osman Nuri; Cheng, Ta-Wui

2006-06-01

Copper waste is iron-rich hazardous waste containing heavy metals such as Cu, Zn, Co, Pb. The results of leaching tests show that the concentration of these elements exceeds the Turkish and EPA regulatory limits. Consequently, this waste cannot be disposed of in its present form and therefore requires treatment to stabilize it or make it inert prior to disposal. Vitrification was selected as the technology for the treatment of the toxic waste under investigation. During the vitrification process significant amounts of the toxic organic and inorganic chemical compounds could be destroyed, and at the same time, the metal species are immobilized as they become an integral part of the glass matrix. The copper flotation waste samples used in this research were obtained from the Black Sea Copper Works of Samsun, Turkey. The samples were vitrified after being mixed with other inorganic waste and materials. The copper flotation waste and their glass-ceramic products were characterized by X-ray analysis (XRD), scanning electron microscopy and by the toxicity characteristic leaching procedure test. The products showed very good chemical durability. The glass-ceramics fabricated at 850 degrees C/2 h have a large application potential especially as construction and building materials.

Essential and toxic elements in seaweeds for human consumption.

PubMed

Desideri, D; Cantaluppi, C; Ceccotto, F; Meli, M A; Roselli, C; Feduzi, L

2016-01-01

Essential elements (K, Ca, P, S, Cl, Mn, Fe, Cu, Zn, Ni, Br, and I) and nonessential or toxic elements (Al, Ti, Si, Rb, Sr, As, Cd, Sn, and Pb) were determined by energy-dispersive polarized x-ray fluorescence spectrometry in 14 seaweeds purchased in local specialty stores in Italy and consumed by humans. The differences in elements between the algae species reached up to 2-4 orders of magnitude. Lithothamnium calcareum showed the highest levels of Ca, Al, Si, Fe, and Ti. Palmaria palmata showed the highest concentrations of K, Rb, and Cl. The highest content of S was in Chondrus crispus. Laminaria digitata contained the highest concentrations of total As, Cd, Sn, Br, and I. The highest concentration of Zn was in Chlorella pyrenoidosa. Ulva lactuca displayed the highest levels of Cu, Ni, Mn, and Pb. Iodine levels ranged from 3.4 in Chlorella pyrenoidosa to 7316 mg/kg(dry) in Laminaria digitata. The nutrimental importance of essential elements was assessed using nutritional requirements. The results showed that the consumption of algae might serve as an important source of the essential elements. Health risk due to the toxic elements present in seaweed was estimated using risk estimators. Total As, Cd, and Pb concentrations ranged from <1 to 67.6, to 7.2 and to 6.7 mg/kg(dry) respectively; therefore, their contribution to total elemental intake does not appear to pose any threat to the consumers, but the concentrations of these elements should be controlled to protect the consumer against potential adverse health risks.

Long-Term Effects of Dredging Operations Program. Long-Term Evaluation of Plants and Animals Colonizing Contaminated Estuarine Dredged Material Placed in Both Upland and Wetland Environments

DTIC Science & Technology

1991-09-01

MP D-91-5, September 1991 References Beckett, P. H. T., and Davis, R. D. 1977. Upper critical levels of toxic elements in plants. New Phytology 79:95...and ryegrass. New Phytology 80:23-42. Davis, R. D., Beckett, P. H. T., and Wollan, E. 1978. Critical levels of twenty potentially toxic elements in

The effects of bio-available copper on macrolide antibiotic resistance genes and mobile elements during tylosin fermentation dregs co-composting.

PubMed

Zhang, Bo; Wang, Meng Meng; Wang, Bing; Xin, Yanjun; Gao, Jiaqi; Liu, Huiling

2018-03-01

In this study, aerobic co-composting of tylosin fermentation dregs (TFDs) and sewage sludge with different adding concentrations of copper (Cu) was investigated to inspect the fate of antibiotic resistance genes (ARGs), metal resistance genes (MRGs) and mobile genetic elements (MGEs). Results showed that two concentrations of Cu did affect not only the abiotic factors but the relative abundances of resistance genes. High concentration of Cu inhibited the metabolic capacity of microbial community and the nitrogen-fixing process while had little effect on the degradation of TYL and TOC. The abundance of ermT, mefA, mphA increased partly attributed to the toxic effects and co-selective pressure from heavy metal reflected by MRGs. There was significant correlation among some environmental factors like pH, bio-Cu, organic matters and ARGs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Targeted polymeric nanoparticles for cancer gene therapy

PubMed Central

Kim, Jayoung; Wilson, David R.; Zamboni, Camila G.; Green, Jordan J.

2015-01-01

In this article, advances in designing polymeric nanoparticles for targeted cancer gene therapy are reviewed. Characterization and evaluation of biomaterials, targeting ligands, and transcriptional elements are each discussed. Advances in biomaterials have driven improvements to nanoparticle stability and tissue targeting, conjugation of ligands to the surface of polymeric nanoparticles enable binding to specific cancer cells, and the design of transcriptional elements has enabled selective DNA expression specific to the cancer cells. Together, these features have improved the performance of polymeric nanoparticles as targeted non-viral gene delivery vectors to treat cancer. As polymeric nanoparticles can be designed to be biodegradable, non-toxic, and to have reduced immunogenicity and tumorigenicity compared to viral platforms, they have significant potential for clinical use. Results of polymeric gene therapy in clinical trials and future directions for the engineering of nanoparticle systems for targeted cancer gene therapy are also presented. PMID:26061296

Mineral Element Contents in Commercially Valuable Fish Species in Spain

PubMed Central

Peña-Rivas, Luis; Ortega, Eduardo; López-Martínez, Concepción; Olea-Serrano, Fátima; Lorenzo, Maria Luisa

2014-01-01

The aim of this study was to measure selected metal concentrations in Trachurus trachurus, Trachurus picturatus, and Trachurus mediterraneus, which are widely consumed in Spain. Principal component analysis suggested that the variable Cr was the main responsible variable for the identification of T. trachurus, the variables As and Sn for T. mediterraneus, and the rest of variables for T. picturatus. This well-defined discrimination between fish species provided by mineral element allows us to distinguish them on the basis of their metal content. Based on the samples collected, and recognizing the inferential limitation of the sample size of this study, the metal concentrations found are below the proposed limit values for human consumption. However, it should be taken into consideration that there are other dietary sources of these metals. In conclusion, metal contents in the fish species analyzed are acceptable for human consumption from a nutritional and toxicity point of view. PMID:24895678

Potential of selected Canadian plant species for phytoextraction of trace elements from selenium-rich soil contaminated by industrial activity.

PubMed

Nissim, Werther Guidi; Hasbroucq, Séverine; Kadri, Hafssa; Pitre, Frederic E; Labrecque, Michel

2015-01-01

In this preliminary screening study, we tested the phytoextraction potential of nine Canadian native/well-adapted plant species on a soil highly polluted by trace elements (TE) from a copper refinery. Plant physiological parameters and soil cover index were monitored for a 12-week period. At the end of the trial, biomass yield, bioconcentration (BFC) and translocation (TF) factors for the main TE as well as phytoextraction potential were determined. Most plants were severely injured by the high pollution levels, showing symptoms of toxicity including chlorosis, mortality and very low biomass yield. However, Indian mustard showed the highest selenium extraction potential (65 mg m(-2)), even under harsh growing conditions. Based on our results, tall fescue and ryegrass, which mainly stored As, Cu, Pb and Zn within roots, could be used effectively for phytostabilization.

Essential and toxic elements in meat of wild birds.

PubMed

Roselli, Carla; Desideri, Donatella; Meli, Maria Assunta; Fagiolino, Ivan; Feduzi, Laura

2016-01-01

Essential and toxic elements were determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES), mass spectrometry (MS), and atomic absorption (AS) in meat of 14 migratory birds originating from central and northern Europe to provide baseline data regarding game meat consumed in central Italy. In all samples analyzed, cobalt (Co) and chromium (Cr) (total) levels were <0.326 mg/kg ww . For nonessential or toxic elements, arsenic (As), barium (Ba), cadmium (Cd), stannous (Sn), thallium (Tl), tellurium (Te), titanium (Ti), cerium (Ce), lantanium (La), and uranium (U) concentrations were <0.326 mg/kg ww, thorium (Th) <1.63 mg/kg ww , and mercury (Hg) <0.0163 mg/kg ww . When detectable, lead (Pb) concentrations always exceeded maximal admissible levels for metal (0.1 mg/kg ww ) established by the European Commission for meat. These findings indicate that elevated Pb concentrations in game ingested by humans may be a cause for concern.

Trace Elements Speciation of Submicron Particulate Matter (PM1) Collected in the Surroundings of Power Plants.

PubMed

Zajusz-Zubek, Elwira; Kaczmarek, Konrad; Mainka, Anna

2015-10-16

This study reports the concentrations of PM1 trace elements (As, Cd, Co, Cr, Hg, Mn, Ni, Pb, Sb and Se) content in highly mobile (F1), mobile (F2), less mobile (F3) and not mobile (F4) fractions in samples that were collected in the surroundings of power plants in southern Poland. It also reports source identification by enrichment factors (EF) and a principal component analysis (PCA). There is limited availability of scientific data concerning the chemical composition of dust, including fractionation analyses of trace elements, in the surroundings of power plants. The present study offers important results in order to fill this data gap. The data collected in this study can be utilized to validate air quality models in this rapidly developing area. They are also crucial for comparisons with datasets from similar areas all over the world. Moreover, the identification of the bioavailability of selected carcinogenic and toxic elements in the future might be used as output data for potential biological and population research on risk assessment. This is important in the context of air pollution being hazardous to human health.

Microbial transformation of elements: the case of arsenic and selenium

USGS Publications Warehouse

Stolz, J.; Basu, P.; Oremland, R.

2002-01-01

Microbial activity is responsible for the transformation of at least one third of the elements in the periodic table. These transformations are the result of assimilatory, dissimilatory, or detoxification processes and form the cornerstones of many biogeochemical cycles. Arsenic and selenium are two elements whose roles in microbial ecology have only recently been recognized. Known as "essential toxins", they are required in trace amounts for growth and metabolism but are toxic at elevated concentrations. Arsenic is used as an osmolite in some marine organisms while selenium is required as selenocysteine (i.e. the twenty-first amino acid) or as a ligand to metal in some enzymes (e.g. FeNiSe hydrogenase). Arsenic resistance involves a small-molecular-weight arsenate reductase (ArsC). The use of arsenic and selenium oxyanions for energy is widespread in prokaryotes with representative organisms from the Crenarchaeota, thermophilic bacteria, low and high G+C gram-positive bacteria, and Proteobacteria. Recent studies have shown that both elements are actively cycled and play a significant role in carbon mineralization in certain environments. The occurrence of multiple mechanisms involving different enzymes for arsenic and selenium transformation indicates several different evolutionary pathways (e.g. convergence and lateral gene transfer) and underscores the environmental significance and selective impact in microbial evolution of these two elements.

Microbial transformation of elements: the case of arsenic and selenium.

PubMed

Stolz, J F; Basu, P; Oremland, R S

2002-12-01

Microbial activity is responsible for the transformation of at least one third of the elements in the periodic table. These transformations are the result of assimilatory, dissimilatory, or detoxification processes and form the cornerstones of many biogeochemical cycles. Arsenic and selenium are two elements whose roles in microbial ecology have only recently been recognized. Known as "essential toxins", they are required in trace amounts for growth and metabolism but are toxic at elevated concentrations. Arsenic is used as an osmolite in some marine organisms while selenium is required as selenocysteine (i.e. the twenty-first amino acid) or as a ligand to metal in some enzymes (e.g. FeNiSe hydrogenase). Arsenic resistance involves a small-molecular-weight arsenate reductase (ArsC). The use of arsenic and selenium oxyanions for energy is widespread in prokaryotes with representative organisms from the Crenarchaeota, thermophilic bacteria, low and high G+C gram-positive bacteria, and Proteobacteria. Recent studies have shown that both elements are actively cycled and play a significant role in carbon mineralization in certain environments. The occurrence of multiple mechanisms involving different enzymes for arsenic and selenium transformation indicates several different evolutionary pathways (e.g. convergence and lateral gene transfer) and underscores the environmental significance and selective impact in microbial evolution of these two elements.

Application of the Total Reflection X-ray Fluorescence technique to trace elements determination in tobacco

NASA Astrophysics Data System (ADS)

Martinez, T.; Lartigue, J.; Zarazua, G.; Avila-Perez, P.; Navarrete, M.; Tejeda, S.

2008-12-01

Many studies have identified an important number of toxic elements along with organic carcinogen molecules and radioactive isotopes in tobacco. In this work we have analyzed by Total Reflection X-Ray Fluorescence 9 brands of cigarettes being manufactured and distributed in the Mexican market. Two National Institute of Standards and Technology standards and a blank were equally treated at the same time. Results show the presence of some toxic elements such as Pb and Ni. These results are compared with available data for some foreign brands, while their implications for health are discussed. It can be confirmed that the Total Reflection X-Ray Fluorescence method provides precise (reproducible) and accuracy (trueness) data for 15 elements concentration in tobacco samples.

Risk assessment of bioaccessible trace elements in smoke haze aerosols versus urban aerosols using simulated lung fluids

NASA Astrophysics Data System (ADS)

Huang, Xian; Betha, Raghu; Tan, Li Yun; Balasubramanian, Rajasekhar

2016-01-01

Smoke-haze episodes, caused by uncontrolled peat and forest fires, occur almost every year in the South-East Asian region with increased concentrations of PM2.5 (airborne particulate matter (PM) with diameter ≤ 2.5 μm). Particulate-bound trace elements (TrElems), especially carcinogenic and toxic elements, were measured during smoke haze as well as non-haze periods in 2014 as they are considered to be indicators of potential health effects. The bioaccessibilities of 13 TrElems were investigated using two types of simulated lung fluids (SLFs), Gamble's solution and artificial lysosomal fluid (ALF), instead of the commonly used leaching agent (water). The dissolution kinetics was also examined for these TrElems. Many TrElems showed higher solubility in SLFs, and were more soluble in ALF compared to the Gamble's solution. Cu, Mn and Cd were observed to be the most soluble trace elements in ALF, while in Gamble's solution the most soluble trace elements were Cu, Mn and Zn. The dissolution rates were highly variable among the elements. Health risk assessment was conducted based on the measured concentrations of TrElems and their corresponding toxicities for three possible scenarios involving interactions between carcinogenic and toxic TrElems and SLFs, using the United States Environmental Protection Agency (USEPA) human health risk assessment model. The cumulative cancer risks exceeded the acceptable level (1 in a million i.e. 1 × 10-6). However, the estimation of health quotient (HQ) indicated no significant chronic toxic health effects. The risk assessment results revealed that the assessment of bioaccessibility of particulate-bound TrElems using water as the leaching agent may underestimate the health risk.

Spatial and temporal trends of selected trace elements in liver tissue from polar bears (Ursus maritimus) from Alaska, Canada and Greenland.

PubMed

Routti, Heli; Letcher, Robert J; Born, Erik W; Branigan, Marsha; Dietz, Rune; Evans, Thomas J; Fisk, Aaron T; Peacock, Elizabeth; Sonne, Christian

2011-08-01

Spatial trends and comparative changes in time of selected trace elements were studied in liver tissue from polar bears from ten different subpopulation locations in Alaska, Canadian Arctic and East Greenland. For nine of the trace elements (As, Cd, Cu, Hg, Mn, Pb, Rb, Se and Zn) spatial trends were investigated in 136 specimens sampled during 2005-2008 from bears from these ten subpopulations. Concentrations of Hg, Se and As were highest in the (northern and southern) Beaufort Sea area and lowest in (western and southern) Hudson Bay area and Chukchi/Bering Sea. In contrast, concentrations of Cd showed an increasing trend from east to west. Minor or no spatial trends were observed for Cu, Mn, Rb and Zn. Spatial trends were in agreement with previous studies, possibly explained by natural phenomena. To assess temporal changes of Cd, Hg, Se and Zn concentrations during the last decades, we compared our results to previously published data. These time comparisons suggested recent Hg increase in East Greenland polar bears. This may be related to Hg emissions and/or climate-induced changes in Hg cycles or changes in the polar bear food web related to global warming. Also, Hg:Se molar ratio has increased in East Greenland polar bears, which suggests there may be an increased risk for Hg(2+)-mediated toxicity. Since the underlying reasons for spatial trends or changes in time of trace elements in the Arctic are still largely unknown, future studies should focus on the role of changing climate and trace metal emissions on geographical and temporal trends of trace elements.

Spatial and temporal trends of selected trace elements in liver tissue from polar bears (Ursus maritimus) from Alaska, Canada and Greenland

USGS Publications Warehouse

Routti, H.; Letcher, R.J.; Born, E.W.; Branigan, M.; Dietz, R.; Evans, T.J.; Fisk, A.T.; Peacock, E.; Sonne, C.

2011-01-01

Spatial trends and comparative changes in time of selected trace elements were studied in liver tissue from polar bears from ten different subpopulation locations in Alaska, Canadian Arctic and East Greenland. For nine of the trace elements (As, Cd, Cu, Hg, Mn, Pb, Rb, Se and Zn) spatial trends were investigated in 136 specimens sampled during 2005-2008 from bears from these ten subpopulations. Concentrations of Hg, Se and As were highest in the (northern and southern) Beaufort Sea area and lowest in (western and southern) Hudson Bay area and Chukchi/Bering Sea. In contrast, concentrations of Cd showed an increasing trend from east to west. Minor or no spatial trends were observed for Cu, Mn, Rb and Zn. Spatial trends were in agreement with previous studies, possibly explained by natural phenomena. To assess temporal changes of Cd, Hg, Se and Zn concentrations during the last decades, we compared our results to previously published data. These time comparisons suggested recent Hg increase in East Greenland polar bears. This may be related to Hg emissions and/or climate-induced changes in Hg cycles or changes in the polar bear food web related to global warming. Also, Hg:Se molar ratio has increased in East Greenland polar bears, which suggests there may be an increased risk for Hg 2+-mediated toxicity. Since the underlying reasons for spatial trends or changes in time of trace elements in the Arctic are still largely unknown, future studies should focus on the role of changing climate and trace metal emissions on geographical and temporal trends of trace elements. ?? 2011 The Royal Society of Chemistry.

Plant-soil distribution of potentially toxic elements in response to elevated atmospheric CO2.

PubMed

Duval, Benjamin D; Dijkstra, Paul; Natali, Susan M; Megonigal, J Patrick; Ketterer, Michael E; Drake, Bert G; Lerdau, Manuel T; Gordon, Gwyneth; Anbar, Ariel D; Hungate, Bruce A

2011-04-01

The distribution of contaminant elements within ecosystems is an environmental concern because of these elements' potential toxicity to animals and plants and their ability to hinder microbial ecosystem services. As with nutrients, contaminants are cycled within and through ecosystems. Elevated atmospheric CO2 generally increases plant productivity and alters nutrient element cycling, but whether CO2 causes similar effects on the cycling of contaminant elements is unknown. Here we show that 11 years of experimental CO2 enrichment in a sandy soil with low organic matter content causes plants to accumulate contaminants in plant biomass, with declines in the extractable contaminant element pools in surface soils. These results indicate that CO2 alters the distribution of contaminant elements in ecosystems, with plant element accumulation and declining soil availability both likely explained by the CO2 stimulation of plant biomass. Our results highlight the interdependence of element cycles and the importance of taking a broad view of the periodic table when the effects of global environmental change on ecosystem biogeochemistry are considered.

Molecular manipulations for enhancing luminescent bioreporters performance in the detection of toxic chemicals.

PubMed

Yagur-Kroll, Sharon; Belkin, Shimshon

2014-01-01

Microbial whole-cell bioreporters are genetically modified microorganisms that produce a quantifiable output in response to the presence of toxic chemicals or other stress factors. These bioreporters harbor a genetic fusion between a sensing element (usually a gene regulatory element responsive to the target) and a reporter element, the product of which may be quantitatively monitored either by its presence or by its activity. In this chapter we review genetic manipulations undertaken in order to improve bioluminescent bioreporter performance by increasing luminescent output, lowering the limit of detection, and shortening the response time. We describe molecular manipulations applied to all aspects of whole-cell bioreporters: the host strain, the expression system, the sensing element, and the reporter element. The molecular construction of whole-cell luminescent bioreporters, harboring fusions of gene promoter elements to reporter genes, has been around for over three decades; in most cases, these two genetic elements are combined "as is." This chapter outlines diverse molecular manipulations for enhancing the performance of such sensors.

Potentially-toxic and essential elements profile of AH1N1 patients in Mexico City

PubMed Central

Moya, Mireya; Bautista, Edgar G.; Velázquez-González, Antonio; Vázquez-Gutiérrez, Felipe; Tzintzun, Guadalupe; García-Arreola, María Elena; Castillejos, Manuel; Hernández, Andrés

2013-01-01

During spring of 2009, a new influenza virus AH1N1 spread in the world causing acute respiratory illness and death, resulting in the first influenza pandemic since 1968. Blood levels of potentially-toxic and essential elements of 40 pneumonia and confirmed AH1N1 were evaluated against two different groups of controls, both not infected with the pandemic strain. Significant concentrations of potentially-toxic elements (lead, mercury, cadmium, chromium, arsenic) along with deficiency of selenium or increased Zn/Cu ratios characterized AH1N1 cases under study when evaluated versus controlled cases. Deficiency of selenium is progressively observed from controls I (influenza like illness) through controls II (pneumonia) and finally pneumonia -AH1N1 infected patients. Cases with blood Se levels greater than the recommended for an optimal cut-off to activate glutathione peroxidase (12.5 μg/dL) recovered from illness and survived. Evaluation of this essential element in critical pneumonia patients at the National Institutes is under evaluation as a clinical trial. PMID:23422930

In Vitro and In Vivo Evaluation of Lactobacillus delbrueckii subsp. bulgaricus KLDS1.0207 for the Alleviative Effect on Lead Toxicity

PubMed Central

Li, Bailiang; Jin, Da; Yu, Shangfu; Etareri Evivie, Smith; Muhammad, Zafarullah; Huo, Guicheng; Liu, Fei

2017-01-01

Lead (Pb) is a toxic contaminating heavy metal that can cause a variety of hazardous effects to both humans and animals. In the present study, Lactobacillus delbrueckii subsp. bulgaricus KLDS1.0207 (L. bulgaricus KLDS1.0207), which has a remarkable Pb binding capacity and Pb tolerance, was selected for further study. It was observed that the thermodynamic and kinetic model of L. bulgaricus KLDS1.0207 Pb binding respectively fit with the Langmuir–Freundlich model and the pseudo second-order kinetic model. Scanning electron microscopy and energy dispersive spectroscopy analysis disclosed that the cell surfaces were covered with Pb and that carbon and oxygen elements were chiefly involved in Pb binding. Combined with Fourier transform infrared spectroscopy analysis, it was revealed that the carboxyl, phosphoryl, hydroxyl, amino and amide groups were the main functional groups involved in the Pb adsorption. The protective effects of L. bulgaricus KLDS1.0207 against acute Pb toxicity in mice was evaluated by prevention and therapy groups, the results in vivo showed that L. bulgaricus KLDS1.0207 treatment could reduce mortality rates, effectively increase Pb levels in the feces, alleviate tissue Pb enrichment, improve the antioxidant index in the liver and kidney, and relieve renal pathological damage. Our findings show that L. bulgaricus KLDS1.0207 can be used as a potential probiotic against acute Pb toxicity. PMID:28786945

In Vitro and In Vivo Evaluation of Lactobacillus delbrueckii subsp. bulgaricus KLDS1.0207 for the Alleviative Effect on Lead Toxicity.

PubMed

Li, Bailiang; Jin, Da; Yu, Shangfu; Etareri Evivie, Smith; Muhammad, Zafarullah; Huo, Guicheng; Liu, Fei

2017-08-08

Lead (Pb) is a toxic contaminating heavy metal that can cause a variety of hazardous effects to both humans and animals. In the present study, Lactobacillus delbrueckii subsp. bulgaricus KLDS1.0207 ( L. bulgaricus KLDS1.0207), which has a remarkable Pb binding capacity and Pb tolerance, was selected for further study. It was observed that the thermodynamic and kinetic model of L. bulgaricus KLDS1.0207 Pb binding respectively fit with the Langmuir-Freundlich model and the pseudo second-order kinetic model. Scanning electron microscopy and energy dispersive spectroscopy analysis disclosed that the cell surfaces were covered with Pb and that carbon and oxygen elements were chiefly involved in Pb binding. Combined with Fourier transform infrared spectroscopy analysis, it was revealed that the carboxyl, phosphoryl, hydroxyl, amino and amide groups were the main functional groups involved in the Pb adsorption. The protective effects of L. bulgaricus KLDS1.0207 against acute Pb toxicity in mice was evaluated by prevention and therapy groups, the results in vivo showed that L. bulgaricus KLDS1.0207 treatment could reduce mortality rates, effectively increase Pb levels in the feces, alleviate tissue Pb enrichment, improve the antioxidant index in the liver and kidney, and relieve renal pathological damage. Our findings show that L. bulgaricus KLDS1.0207 can be used as a potential probiotic against acute Pb toxicity.

Sediment quality in the north coastal basin of Massachusetts, 2003

USGS Publications Warehouse

Breault, Robert F.; Ashman, Mary S.; Heath, Douglas

2004-01-01

The U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, completed a reconnaissance-level study of bottom-sediment quality in selected lakes, rivers, and estuaries in the North Coastal Basin of Massachusetts. Bottom-sediment grab samples were collected from 20 sites in the North River, Lake Quannapowitt, Saugus River, Mill River, Shute Brook, Sea Plane Basin, Pines River, and Bear Creek. The samples were tested for various types of potentially harmful contaminants? including 33 elements, 17 polyaromatic hydrocarbons (PAHs), 22 organochlorine pesticides, and 7 polychlorinated biphenyl (PCB) mixtures (Aroclors)?to benthic organisms (bottom-dwelling) and humans. The results were compared among sampling sites, to background concentrations, and to concen-trations measured in other urban rivers, and sediment-quality guidelines were used to predict toxicity at the sampling sites to benthic organisms and humans. Because there are no standards for human toxicity for aquatic sediment, standards for contaminated upland soil were used. Contaminant concentrations measured in sediment collected from the North Coastal Basin generally were equal to or greater than concentrations in sediment from uncontaminated rivers throughout New England. Contaminants in North Coastal Basin sediment with elevated concentrations (above back-ground levels) included arsenic, chromium, copper, lead, nickel, and zinc, some of the PAHs, dichlorodiphenyltrichloro-ethane (DDT) and its metabolites, and dieldrin. No PCBs were measured above the detection limits. Measured concentrations of arsenic, chromium, and lead were also generally greater than those measured in other urban rivers throughout the conter-minous United States. With one exception (arsenic), local con-centrations measured in sediment samples collected from the North Coastal Basin were lower than concentrations measured in sediment collected from two of three urban rivers draining to Boston Harbor. The probable toxicity to benthic organisms ranged from about 33 to 91 percent across the study area. Of the elements analyzed, antimony, arsenic, beryllium, and lead exceeded the soil standards for risk to human health. Of the PAHs analyzed, four also exceeded soil standards. Organochlorine pesticide concentrations, however, were not high enough relative to the soil standards to pose a risk to human health. Some trace element and some organic compound concentrations in bottom sediment may be toxic to aquatic organisms and may pose a risk to human health.

Spatial distribution of dust-bound trace elements in Pakistan and their implications for human exposure.

PubMed

Eqani, Syed Ali Musstjab Akber Shah; Kanwal, Ayesha; Bhowmik, Avit Kumar; Sohail, Mohammad; Ullah, Rizwan; Ali, Syeda Maria; Alamdar, Ambreen; Ali, Nadeem; Fasola, Mauro; Shen, Heqing

2016-06-01

This study aims to assess the spatial patterns of selected dust-borne trace elements alongside the river Indus Pakistan, their relation with anthropogenic and natural sources, and the potential risk posed to human health. The studied elements were found in descending concentrations: Mn, Zn, Pb, Cu, Ni, Cr, Co, and Cd. The Index of Geo-accumulation indicated that pollution of trace metals were higher in lower Indus plains than on mountain areas. In general, the toxic elements Cr, Mn, Co and Ni exhibited altitudinal trends (P < 0.05). The few exceptions to this trend were the higher values for all studied elements from the northern wet mountainous zone (low lying Himalaya). Spatial PCA/FA highlighted that the sources of different trace elements were zone specific, thus pointing to both geological influences and anthropogenic activities. The Hazard Index for Co and for Mn in children exceeded the value of 1 only in the riverine delta zone and in the southern low lying zone, whereas the Hazard Index for Pb was above the bench mark for both children and adults (with few exceptions) in all regions, thus indicating potential non-carcinogenic health risks. These results will contribute towards the environmental management of trace metal(s) with potential risk for human health throughout Pakistan. Copyright © 2016 Elsevier Ltd. All rights reserved.

Heavy metals pollution status in surface sediments (rivers and artifical lakes, Serbia)

NASA Astrophysics Data System (ADS)

Sakan, Sanja; Đorđević, Dragana

2017-04-01

Potentially hazardous trace elements, often in literature referred as "heavy metals", are deemed serious pollutants due to their toxicity, persistence and non-degradability in the environment. These elements play an important role in extent of water pollution and threaten the health of populations and ecosystems. As the sink of heavy metals, sediment beds adsorb metals in quantities that are many times higher than those found in the water column in the long-term polluted water environment. It is believed that most of the metal content, as much as 90% in aquatic sediments is bound to sediments. Metal contamination in these sediments could be directly affect the river water quality, resulting in potential consequences to the sensitive lowest levels of the food chain and ultimately to human health. The objective of this research was the evaluation of heavy metal contamination level in sediments of the most important rivers and artificial lakes in Serbia. The heavy metal enrichment in studied sediments was conducted by using: determination of total metal content, sequential extraction procedure for the fractionation of studied elements, quantification of the metal enrichment degree in the sediments by calculating geo-accumulation indices, determination of actual and potential element availability and application of BRAI index for the assessment of heavy metal bioavailability. The sediments were found to be contaminated by heavy metals to various extents, mostly with Cd, Cu, and Zn. The significant variation in heavy metal distribution among samples collected in this large region, encompassing all Serbian watersheds, suggests the selective contamination of sediments by heavy metals. Elevated concentrations of elements in most cases were detected in samples of river sediments, since artificial lake reservoirs are usually built in rural areas, where the less anthropogenic pollution. Rivers often flow through the towns and these water basins less or more loaded micronutrients, toxic substances, organic or inorganic, waste materials, depending on the species and type of industrial processes that are often without the necessary technological and mandatory treatment directly discharged into them. Due to the potential risk of heavy metal pollution in studied sediments, pollution prevention and control measurements seems necessary, especially in areas where we found increased levels of these elements.

Alterations of mitochondrial DNA in CEM cells selected for resistance toward ddC toxicity.

PubMed

Bjerke, M; Franco, M; Johansson, M; Balzarini, J; Karlsson, A

2006-01-01

2 ',3 '-dideoxycytidine (ddC) is a nucleoside analog that has been shown to produce a delayed toxicity which may be due to the depletion of mitochondrial DNA (mtDNA). In order to gain further understanding of the events involved in mitochondrial toxicity, two different CEM cell lines were selected for resistance to the delayed ddC toxicity.

SEM-EDS-Based Elemental Identification on the Enamel Surface after the Completion of Orthodontic Treatment: In Vitro Studies

PubMed Central

Seeliger, Julia; Lipski, Mariusz; Wójcicka, Anna; Gedrange, Tomasz; Woźniak, Krzysztof

2016-01-01

Braces as foreign bodies in the mouth carry a risk of side effects and toxicity to the human body. This article presents the results indicating the possible toxic effects of tools used for cleaning the enamel after the completion of orthodontic treatment. The studies were carried out in vitro. The procedure of enamel etching, bonding orthodontic metal brackets, and enamel cleaning after their removal was performed under laboratory conditions. The enamel microstructure and elements present on its surface were evaluated using the scanning electron microscope (SEM). Silicon and aluminium were found in addition to the tooth building elements. PMID:27766265

Relationship of Indoor, Outdoor and Personal Air (RIOPA) study: study design, methods and quality assurance/control results.

PubMed

Weisel, Clifford P; Zhang, Junfeng; Turpin, Barbara J; Morandi, Maria T; Colome, Steven; Stock, Thomas H; Spektor, Dalia M; Korn, Leo; Winer, Arthur; Alimokhtari, Shahnaz; Kwon, Jaymin; Mohan, Krishnan; Harrington, Robert; Giovanetti, Robert; Cui, William; Afshar, Masoud; Maberti, Silvia; Shendell, Derek

2005-03-01

The Relationship of Indoor, Outdoor and Personal Air (RIOPA) Study was undertaken to evaluate the contribution of outdoor sources of air toxics, as defined in the 1990 Clean Air Act Amendments, to indoor concentrations and personal exposures. The concentrations of 18 volatile organic compounds (VOCs), 17 carbonyl compounds, and fine particulate matter mass (PM(2.5)) were measured using 48-h outdoor, indoor and personal air samples collected simultaneously. PM2.5 mass, as well as several component species (elemental carbon, organic carbon, polyaromatic hydrocarbons and elemental analysis) were also measured; only PM(2.5) mass is reported here. Questionnaires were administered to characterize homes, neighborhoods and personal activities that might affect exposures. The air exchange rate was also measured in each home. Homes in close proximity (<0.5 km) to sources of air toxics were preferentially (2:1) selected for sampling. Approximately 100 non-smoking households in each of Elizabeth, NJ, Houston, TX, and Los Angeles, CA were sampled (100, 105, and 105 respectively) with second visits performed at 84, 93, and 81 homes in each city, respectively. VOC samples were collected at all homes, carbonyls at 90% and PM(2.5) at 60% of the homes. Personal samples were collected from nonsmoking adults and a portion of children living in the target homes. This manuscript provides the RIOPA study design and quality control and assurance data. The results from the RIOPA study can potentially provide information on the influence of ambient sources on indoor air concentrations and exposure for many air toxics and will furnish an opportunity to evaluate exposure models for these compounds.

Bioavailability and health risk assessment of potentially toxic elements in Thriasio Plain, near Athens, Greece.

PubMed

Antoniadis, Vasileios; Golia, Evangelia E; Shaheen, Sabry M; Rinklebe, Jörg

2017-04-01

Elevated concentrations of potentially toxic elements (PTEs) are usually found in areas of intense industrial activity. Thriasio Plain is a plain near Athens, Greece, where most of the heavy industry of the country has been situated for decades, but it also is a residential and horticultural area. We aimed at measuring the levels of PTEs in soils and indigenous plant species and assessing the health risk associated with direct soil ingestion. Samples of soils at roadsides and growing plants were collected from 31 sites of that area. Concentrations of Al, As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, V and Zn were measured in both soils (as pseudo-total) and aerial plant tissues. We found that As, Cd, Cr, Cu, Ni, Pb and Zn were higher than maximum regulatory limits. Element concentrations in plants were rather lower than expected, probably because indigenous plants have developed excluder behaviour over time. Copper and Zn soil-to-plant coefficients were highest among the other elements; for Cu this was unexpected, and probably associated with recent Cu-releasing industrial activity. Risk assessment analysis indicated that As was the element contributing more than 50 % of the health risk related to direct soil ingestion, followed by Cr, Pb, and, surprisingly, Mn. We concluded that in a multi-element contamination situation, elevated risk of PTEs (such as As, Cr and Pb) may reduce the tolerance limits of exposure to less-toxic elements (here, Mn).

Microbial transformations of arsenic in the environment: From soda lakes to aquifers

USGS Publications Warehouse

Lloyd, J.R.; Oremland, R.S.

2006-01-01

Arsenic is a highly toxic element that supports a surprising range of biogeochemical transformations. The biochemical basis of these microbial interactions is described, with an emphasis on energy-yielding redox biotransformations that cycle between the As5+ and As3+ oxidation states. The subsequent impact of As3+-oxidising and As 5+-reducing prokaryotes on the chemistry of selected environments is also described, focusing on soda lakes with naturally high concentrations of the metalloid and on Southeast Asian aquifer sediments, where the microbial reduction of sorbed As5+ and subsequent mobilisation of As 3+ into water abstracted for drinking and irrigation threaten the lives of millions.

Continuous-flow leaching in a rotating coiled column for studies on the mobility of toxic elements in dust samples collected near a metallurgic plant.

PubMed

Fedotov, Petr S; Ermolin, Mikhail S; Ivaneev, Alexandr I; Fedyunina, Natalia N; Karandashev, Vasily K; Tatsy, Yury G

2016-03-01

Continuous-flow (dynamic) leaching in a rotating coiled column has been applied to studies on the mobility of Zn, Cd, Cu, Pb, Ni, Sb, As, S, and other potentially toxic elements in atmospherically deposited dust samples collected near a large copper smelter (Chelyabinsk region, Russia). Water and simulated "acid rain" (pH 4) were used as eluents. The technique enables not only the fast and efficient leaching of elements but as well time-resolved studies on the mobilization of heavy metals, sulphur, and arsenic in environmentally relevant forms to be made. It is shown that up to 1.5, 4.1, 1.9, 11.1, and 46.1% of Pb, As, Cu, Zn, and S, correspondingly, can be easily mobilized by water. Taking into consideration that the total concentrations of these elements in the samples under investigation are surprisingly high and vary in the range from 2.7 g/kg (for arsenic) to 15.5 g/kg (for sulphur), the environmental impact of the dust may be dramatic. The simulated acid rain results in somewhat higher recoveries of elements, except Cu and Pb. The proposed approach and the data obtained can very useful for the risk assessment related to the mobility of potentially toxic elements and their inclusion in the biogeochemical cycle. Copyright © 2015 Elsevier Ltd. All rights reserved.

Arabidopsis and the Genetic Potential for the Phytoremediation of Toxic Elemental and Organic Pollutants

PubMed Central

Cobbett, Christopher S.; Meagher, Richard B.

2002-01-01

In a process called phytoremediation, plants can be used to extract, detoxify, and/or sequester toxic pollutants from soil, water, and air. Phytoremediation may become an essential tool in cleaning the environment and reducing human and animal exposure to potential carcinogens and other toxins. Arabidopsis has provided useful information about the genetic, physiological, and biochemical mechanisms behind phytoremediation, and it is an excellent model genetic organism to test foreign gene expression. This review focuses on Arabidopsis studies concerning: 1) the remediation of elemental pollutants; 2) the remediation of organic pollutants; and 3) the phytoremediation genome. Elemental pollutants include heavy metals and metalloids (e.g., mercury, lead, cadmium, arsenic) that are immutable. The general goal of phytoremediation is to extract, detoxify, and hyperaccumulate elemental pollutants in above-ground plant tissues for later harvest. A few dozen Arabidopsis genes and proteins that play direct roles in the remediation of elemental pollutants are discussed. Organic pollutants include toxic chemicals such as benzene, benzo(a)pyrene, polychlorinated biphenyls, trichloroethylene, trinitrotoluene, and dichlorodiphenyltrichloroethane. Phytoremediation of organic pollutants is focused on their complete mineralization to harmless products, however, less is known about the potential of plants to act on complex organic chemicals. A preliminary survey of the Arabidopsis genome suggests that as many as 700 genes encode proteins that have the capacity to act directly on environmental pollutants or could be modified to do so. The potential of the phytoremediation proteome to be used to reduce human exposure to toxic pollutants appears to be enormous and untapped. PMID:22303204

Free-ranging domestic cats are characterized by increased metal content in reproductive tissues.

PubMed

Rzymski, Piotr; Niedzielski, Przemysław; Poniedziałek, Barbara; Rzymski, Paweł; Pacyńska, Joanna; Kozak, Lidia; Dąbrowski, Piotr

2015-12-01

Trace metals may be supportive to mammalian reproduction but also reveal certain toxicities. The present study investigated the content of selected metals (Ca, Cd, Cu, Mn, Mg, Ni, Pb, Zn) in uterine and testicular tissue of free-ranging and household cats and its relation with hair metal status, cats' age, weight, physical activity, diet and inhabited environment. Free-rangers and cats not fed by humans were characterized by higher concentrations of essential metals in their reproductive tissues as well as increased levels of toxic elements, particularly Cd and Ni. No difference in metal status was found for household individuals fed on different varieties of commercial food. Cats inhabiting urbanized areas were characterized by higher Pb levels in their reproductive system. Feline hair was found to be less, if at all, susceptible to environmental, lifestyle and dietary variables and most importantly, did not reflect a metal burden in reproductive tissues. Copyright © 2015 Elsevier Inc. All rights reserved.

Toxicity of Cold Lake Blend and Western Canadian Select dilbits to standard aquatic test species

EPA Science Inventory

Dilbits are blends of bitumen and natural gas condensates or crude oils with only limited toxicity data. Two dilbits, Cold Lake Blend and Western Canadian Select, were tested as either unweathered or weathered oils for acute and chronic toxicity to standard freshwater and estuari...

Computer Simulation Lends New Insights Into Cyanide-Caused Cardiac Toxicity

DTIC Science & Technology

2004-12-01

COMPUTER SIMULATION LENDS NEW INSIGHTS INTO CYANIDE-CAUSED CARDIAC TOXICITY C.K. Zoltani* U.S. Army Research Laboratory Computational and...Into Cyanide-Caused Cardiac Toxicity 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK...disequilibrium in the membrane currents caused by the cyanide has grave implications for the cell’s electrophysiology. CN-caused cardiac toxicity shares

Trace elements in coal. Environmental and health significance

USGS Publications Warehouse

Finkelman, R.B.

1999-01-01

Trace elements can have profound adverse effects on the health of people burning coal in homes or living near coal deposits, coal mines, and coal- burning power plants. Trace elements such as arsenic emitted from coal- burning power plants in Europe and Asia have been shown to cause severe health problems. Perhaps the most widespread health problems are caused by domestic coal combustion in developing countries where millions of people suffer from fluorosis and thousands from arsenism. Better knowledge of coal quality characteristics may help to reduce some of these health problems. For example, information on concentrations and distributions of potentially toxic elements in coal may help delineate areas of a coal deposit to be avoided. Information on the modes of occurrence of these elements and the textural relations of the minerals in coal may help to predict the behavior of the potentially toxic trace metals during coal cleaning, combustion, weathering, and leaching.

Particle size effects on bioaccessible amounts of ingestible soil-borne toxic elements.

PubMed

Qin, Junhao; Nworie, Obinna Elijah; Lin, Chuxia

2016-09-01

The unified BARGE method was used to examine the effects of soil particle size on the bioaccessible amounts of potentially toxic elements in multi-contaminated soils from a closed landfill site. The results show that bioaccessible As, Al, Cd, Cr, Cu, Mn, Ni, Pb and Zn increased with decreasing soil particle size and the <0.002 mm soil fraction contained much greater amounts of the bioaccessible elements, as compared to other soil fractions (0.002-0.063 mm, 0.063-0.125 mm, and 0.125-0.250 mm). As, Al and Cr had much lower bioaccessibility, as compared to the six cationic heavy metals. In contrast with other elements, As bioaccessibility tended to be higher in the gastrointestinal phase than in the gastric phase. There was a significant soil particle size effect on bioaccessibility of As and Al in the gastrointestinal phase: As bioaccessibility decreased with decreasing particle size, and the finer soil fractions tended to have a higher Al bioaccessibility, as compared to the coarser soil fractions. The research findings prompt the need for further division of soil particle size fractions in order to more accurately assess the bioaccessible amounts of soil-borne potentially toxic elements in contaminated lands. Copyright © 2016 Elsevier Ltd. All rights reserved.

Potentially toxic elements in foodcrops: Triticum aestivum L., Zea mays L.

NASA Astrophysics Data System (ADS)

Bini, Claudio; Fontana, Silvia; Squizzato, Stefania; Minello, Fabiola; Fornasier, Flavio; Wahsha, Mohammad

2013-04-01

Soil is the basis of the ecosystems and of our system of food production. Crops can uptake heavy metals and potentially toxic elements from the soil and store them in the roots or translocate them to the aerial parts. Excessive content of these elements in edible parts can produce toxic effects and, through the food chain and food consumption, result in a potential hazard for human health. In this study soils and plants (spring wheat, Triticum aestivum L. and maize, Zea mays L.) from a tannery district in North-East Italy were analyzed to determine pedological characters, soil microbial indicators and the content of some major and micro-nutrients and potentially toxic elements (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, P, Pb, S, Zn, V). The soils of the area are moderately polluted; Cr is the most important inorganic contaminant, followed by Ni, Cu and V. Factor analysis evidenced that the contaminants are in part anthropogenic and in part geogenic. Major anthropogenic origin was detected for Cr, Ni (from industrial activities), Zn, Cu, Cd (from agriculture practices). Biological Absorption Coefficient (BAC) from soil to plant roots and Translocation factor (TF) within the plant were calculated; major nutrients (K, P, S) and some micronutrients (Cu, Zn, Mg, Mn) are easily absorbed and translocated, whilst other nutrients (Ca, Fe) and potentially toxic elements or micronutrients (Al, Cd, Cr, Ni, Pb, V) are not accumulated in the seeds of the two considered species. However, the two edible species proved differently able to absorb and translocate elements, and this suggests to consider separately every species as potential PHEs transporter to the food chain and to humans. Cr concentrations in seeds and other aerial parts (stem and leaves) of the examined plants are higher than the values found for the same species and for other cereals grown on unpolluted soils. Comparing the Cr levels in edible parts with recommended dietary intake, besides other possible Cr sources (dust ingestion, water), there seems to be no health risk for animal breeding and population due to the consumption of wheat and maize grown in the area.

Wheat phytotoxicity from arsenic and cadmium separately and together in solution culture and in a calcareous soil

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

Cao, Q; Hu, Q; Khan, S

2007-03-05

The toxicity effect of two deleterious elements of arsenic (As) and cadmium (Cd) (individually or in combination) on root elongation of wheat seedlings (Triticum aestivum, L.) were investigated both in hydroponics and in soils freshly spiked with the toxic elements. Median effective concentration (EC{sub 50}) and non-observed effect concentration (NOEC) were used to investigate the toxic thresholds and potencies of the two elements. The EC{sub 50} for As was 0.97 {mu}M in hydroponics and 196 mg {center_dot} kg{sup -1} in soil, and 4.32 {mu}M and 449 mg {center_dot} kg{sup -1} for Cd, respectively. Toxic unit (TU) and additive index (AI)more » concepts were introduced to determine the combined outcomes, and different behaviors were obtained: synergism in solution culture (EC{sub 50mix} = 0.36 TU{sub mix} and AI: 1.76) and antagonism in soil experiments (EC{sub 50mix} = 1.49 TU{sub mix} and AI: -0.33). Furthermore, the data of soil bioavailable As and Cd can not explain the discrepancy between the results derived from soil and hydroponics experiments.« less

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the American Falls Reservoir area, Idaho, 1988-89. Water Resources Investigation

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

Low, W.H.; Mullins, W.H.

1990-01-01

The report presents results of a reconnaissance investigation to determine whether potentially toxic concentrations of selected trace elements or organochlorine compounds associated with irrigation drainage exist in surface and ground water, bottom sediment, aquatic plants, benthic invertebrates, fish, and waterbirds in the American Falls Reservoir area. American Falls Reservoir was selected for investigation in part because several previous investigations of fish in the reservoir indicated that mercury and cadmium concentrations exceeded human health standards and periodic botulism-related die-offs of waterbirds have been known to occur. Also, rocks south and southeast of the reservoir contain naturally occurring selenium concentrations many timesmore » greater than those in the continental crust. Samples of water, bottom sediment, aquatic plants, benthic invertebrates, fish, and waterbirds were collected from nine sites in the American Falls Reservoir area. The samples were analyzed for selected inorganic and organic constituents to determine whether concentrations exceeded known standards or criteria.« less

Radionuclides and toxic elements transfer from the princess dump to water in Roodepoort, South Africa.

PubMed

Dlamini, S G; Mathuthu, M M; Tshivhase, V M

2016-03-01

High concentrations of radionuclides and toxic elements in gold mine tailings facilities present a health hazard to the environment and people living near that area. Soil and water samples from selected areas around the Princess Mine dump were collected. Soil sampling was done on the surface (15 cm) and also 100 cm below the surface. Water samples were taken from near the dump, mid-stream and the flowing part of the stream (drainage pipe) passing through Roodepoort from the mine dump. Soil samples were analyzed by gamma-ray spectroscopy using a HPGe detector to determine the activity concentrations of (238)U, (232)Th and (4) (​40)K from the activities of the daughter nuclides in the respective decay chains. The average activity concentrations for uranium and thorium in soil were calculated to be 129 ± 36.1 Bq/kg and 18.1 ± 4.01 Bq/kg, respectively. Water samples were analyzed using Inductively Coupled Plasma Mass Spectrometer. Transfer factors for uranium and thorium from soil to water (at point A closest to dump) were calculated to be 0.494 and 0.039, respectively. At point Z2, which is furthest from the dump, they were calculated to be 0.121 and 0.004, respectively. These transfer factors indicate that there is less translocation of the radionuclides as the water flows. Copyright © 2016 Elsevier Ltd. All rights reserved.

Assessment of the potential health risks associated with the aluminium, arsenic, cadmium and lead content in selected fruits and vegetables grown in Jamaica.

PubMed

Antoine, Johann M R; Fung, Leslie A Hoo; Grant, Charles N

2017-01-01

Thirteen Jamaican-grown food crops - ackee ( Blighia sapida ), banana ( Musa acuminate ), cabbage ( Brassica oleracea ), carrot ( Daucus carota ), cassava ( Manihot esculenta ), coco ( Xanthosoma sagittifolium ), dasheen ( Colocasia esculenta ), Irish potato ( Solanum tuberosum ), pumpkin ( Cucurbita pepo ), sweet pepper ( Capsicum annuum ), sweet potato ( Ipomoea batatas ), tomato ( Solanum lycopersicum ) and turnip ( Brassica rapa ) - were analysed for aluminium, arsenic, cadmium and lead by atomic absorption spectrophotometry and instrumental neutron activation analysis. The fresh weight mean concentrations in these food crops (4.25-93.12 mg/kg for aluminium; 0.001-0.104 mg/kg for arsenic; 0.015-0.420 mg/kg for cadmium; 0.003-0.100 mg/kg for lead) were used to calculate the estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI) and target cancer risk (TCR) for arsenic, associated with dietary exposure to these potentially toxic elements. Each food type had a THQ and HI < 1 indicating no undue non-carcinogenic risk from exposure to a single or multiple potentially toxic elements from the same food. The TCR for arsenic in these foods were all below 1 × 10 -4 , the upper limit used for acceptable cancer risk. There is no significant health risk to the consumer associated with the consumption of these Jamaican-grown food crops.

Detection of hazardous pollutants in chrome-tanned leather using locally developed laser-induced breakdown spectrometer.

PubMed

Nasr, M M; Gondal, Mohammed Asharf; Seddigi, Z S

2011-04-01

Highly toxic contaminants like Cr, As, and Pb were detected in chrome-tanning process of animal skin to produce leather by applying locally developed laser-induced breakdown spectrometer. An Nd-YAG laser with 1,064 nm wavelength was focused on the surface of leather samples (natural and manufactured) to generate a plasma spark and spectrally resolved spectra were used for identification and quantification of contaminants. The leather samples were collected from a tannery located in industrial cities of Riyadh and Jeddah, Saudi Arabia. The study was carried out on fully, half manufactured (wet blue leather), and natural hide (skin). To the best of our knowledge, this is the first attempt where laser-induced breakdown spectroscopy (LIBS) technique has been applied for the analysis of leather before and after tanning process. The maximum concentration of different elements of environmental significance like chromium, lead, arsenic, sulfur, magnesium were 199, 289, 31, 38, and 39 ppm, respectively, in one of the manufactured leather samples. The limit of detection (LOD) of our LIBS system for chromium, lead, arsenic, sulfur, and magnesium were 2, 3, 1.5,7, and 3 ppm, respectively. The safe permissible limit for tanned leather for highly toxic elements like chromium, lead, and arsenic are 1, 0.5, 0.01 ppm, respectively, as prescribed in Environmental Regulation Standards for Saudi Industries set by Royal Commission Jubail, Saudi Arabia. The LIBS technique is superior to other conventional techniques like ICP or atomic absorption that a little or no sample preparation is required, no chemicals are needed, multi-elemental analysis is possible for all kinds of samples (natural and anthropogenic materials), microgram of sample is essential, and LIBS could be applied for remote analysis. It is highly selective and sensitivity higher than ICP, and as no sample and chemicals are required, it is cost effective for multi-sample analysis per unit time as compared with other conventional techniques. The concentration of some toxic elements (Cr, Pb, As) is much higher than the safe permissible limits set by Occupational Safety and Health Administration in USA or Saudi environmental regulatory agencies. Results obtained with our LIBS systems were in close agreement with the results obtained using other standard analytical technique such as the inductively coupled plasma atomic emission spectroscopy.

Specifically Designed Constructed Wetlands: A Novel Treatment Approach for Scrubber Wastewater

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

John H. Rodgers Jr; James W. Castle; Chris Arrington: Derek Eggert

2005-09-01

A pilot-scale wetland treatment system was specifically designed and constructed at Clemson University to evaluate removal of mercury, selenium, and other constituents from flue gas desulfurization (FGD) wastewater. Specific objectives of this research were: (1) to measure performance of a pilot-scale constructed wetland treatment system in terms of decreases in targeted constituents (Hg, Se and As) in the FGD wastewater from inflow to outflow; (2) to determine how the observed performance is achieved (both reactions and rates); and (3) to measure performance in terms of decreased bioavailability of these elements (i.e. toxicity of sediments in constructed wetlands and toxicity ofmore » outflow waters from the treatment system). Performance of the pilot-scale constructed wetland treatment systems was assessed using two criteria: anticipated NPDES permit levels and toxicity evaluations using two sentinel toxicity-testing organisms (Ceriodaphnia dubia and Pimephales promelas). These systems performed efficiently with varied inflow simulations of FGD wastewaters removing As, Hg, and Se concentrations below NPDES permit levels and reducing the toxicity of simulated FGD wastewater after treatment with the constructed wetland treatment systems. Sequential extraction procedures indicated that these elements (As, Hg, and Se) were bound to residual phases within sediments of these systems, which should limit their bioavailability to aquatic biota. Sediments collected from constructed wetland treatment systems were tested to observe toxicity to Hyalella azteca or Chironomus tetans. Complete survival (100%) was observed for H. azteca in all cells of the constructed wetland treatment system and C. tentans had an average of 91% survival over the three treatment cells containing sediments. Survival and growth of H. azteca and C. tentans did not differ significantly between sediments from the constructed wetland treatment system and controls. Since the sediments of the constructed wetland treatment system are repositories for As, Hg, and Se and the bioavailability of these elements decreased after deposition, the pilot-scale constructed wetland treatment system contributed significantly to mitigation of risks to aquatic life from these elements.« less

Transformations of Heavy Metals and Plant Nutrients in Dredged Sediments as Affected by Oxidation Reduction Potential and pH. Volume 1. Literature Review

DTIC Science & Technology

1977-05-01

895-896 (1974). 191. Fagerstrom, T., and Jernelov, A. "Formation of Methyl Mercury from Pure Mercuric Sulphide in Aerobic Organic Sediment." Water...was available. The toxic and nutrient elements included are lead, cadmium, mercury , arsenic, selenium, copper, zinc, manganese, iron, nitrogen...on the exchange of these materials between sediment and water. The toxic and nutrient elements included are lead, cadmium, mercury , ar- senic

An evaluation of inorganic toxicity reference values for use in assessing hazards to American robins (Turdus migratorius)

USGS Publications Warehouse

Beyer, W. Nelson; Sample, Bradley E.

2017-01-01

When performing screening-level and baseline risk assessments, assessors usually compare estimated exposures of wildlife receptor species with toxicity reference values (TRVs). We modeled the exposure of American robins (Turdus migratorius) to 10 elements (As, Cd, Cr, Cu, Hg, Mn, Pb, Se, Zn, and V) in spring and early summer, a time when earthworms are the preferred prey. We calculated soil benchmarks associated with possible toxic effects to these robins from 6 sets of published TRVs. Several of the resulting soil screening-level benchmarks were inconsistent with each other and less than soil background concentrations. Accordingly, we examined the derivations of the TRVs as a possible source of error. In the case of V, a particularly toxic chemical compound (ammonium vanadate) containing V, not normally present in soil, had been used to estimate a TRV. In the cases of Zn and Cu, use of uncertainty values of 10 in estimating TRVs led to implausibly low soil screening values. In the case of Pb, a TRV was calculated from studies demonstrating reductions in egg production in Japanese quail (Coturnix coturnix japonica) exposed to Pb concentrations well below than those causing toxic effects in other species of birds. The results on quail, which were replicated in additional trials, are probably not applicable to other, unrelated species, although we acknowledge that only a small fraction of all species of birds has been tested. These examples underscore the importance of understanding the derivation and relevance of TRVs before selecting them for use in screening or in ecological risk assessment.

Heavy Metals and Related Trace Elements.

ERIC Educational Resources Information Center

Leland, Harry V.; And Others

1978-01-01

Presents a literature review of heavy metals and related trace elements in the environment, covering publications of 1976-77. This review includes: (1) trace treatment in natural water and in sediments; and (2) bioaccumulation and toxicity of trace elements. A list of 466 references is presented. (HM)

Root anatomy and element distribution vary between two Salix caprea isolates with different Cd accumulation capacities

PubMed Central

Vaculík, Marek; Konlechner, Cornelia; Langer, Ingrid; Adlassnig, Wolfram; Puschenreiter, Markus; Lux, Alexander; Hauser, Marie-Theres

2012-01-01

The understanding of the influence of toxic elements on root anatomy and element distribution is still limited. This study describes anatomical responses, metal accumulation and element distribution of rooted cuttings of Salix caprea after exposure to Cd and/or Zn. Differences in the development of apoplastic barriers and tissue organization in roots between two distinct S. caprea isolates with divergent Cd uptake and accumulation capacities in leaves might reflect an adaptive predisposition based on different natural origins. Energy-dispersive X-ray spectroscopy (EDX) revealed that Cd and Zn interfered with the distribution of elements in a tissue- and isolate-specific manner. Zinc, Ca, Mg, Na and Si were enriched in the peripheral bark, K and S in the phloem and Cd in both vascular tissues. Si levels were lower in the superior Cd translocator. Since the cuttings originated from stocks isolated from polluted and unpolluted sites we probably uncovered different strategies against toxic elements. PMID:22325439

Tier 3 Toxicity Value White Paper

EPA Pesticide Factsheets

The purpose of this white paper is to articulate the issues pertaining to Tier 3 toxicity values and provide recommendations on processes that will improve the transparency and consistency of identifying, evaluating, selecting, and documenting Tier 3 toxicity values for use in the Superfund and Resource Conservation and Recovery Act (RCRA) programs. This white paper will be used to assist regional risk assessors in selecting Tier 3 toxicity values as well as provide the foundation for future regional and national efforts to improve guidance and policy on Tier 3 toxicity values.

Trace Elements in Hair from Tanzanian Children: Effect of Dietary Factor (abstract)

NASA Astrophysics Data System (ADS)

Mohammed, Najat K.; Spyrou, Nicholas M.

2009-04-01

Trace elements in certain amounts are essential for childrens' health, because they are present in tissues participating in metabolic reactions of organisms. Deficiency of the essential elements may result in malnutrition, impaired body immunity, and poor resistance to disease. These conditions might be enhanced against a background of additional adverse environmental factors such as toxic elements. The analysis of elements in childrens' hair will give information on the deficiency of essential elements and excess of toxic elements in relation to their diet. In this study, 141 hair samples from children (girls and boys) living in two regions of Tanzanian mainland (Dar es Salaam and Moshi) and the island of Zanzibar have been analysed for trace elements in relation to food consumption habits. The analysis was carried out using long and short irradiation instrumental neutron activation analysis (INAA) of the Nuclear Physics Institute at Rez, Czech Republic. Arithmetic and geometric means with their respective standard deviations are presented for 19 elements. Subgroups were formed according to age, gender, and geographic regions from which the samples were collected. Differences in concentrations for the groups and with other childhood populations were explored and discussed.

Trace Elements in Hair from Tanzanian Children: Effect of Dietary Factor

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

Mohammed, Najat K.; Spyrou, Nicholas M.

2009-04-19

Trace elements in certain amounts are essential for childrens' health, because they are present in tissues participating in metabolic reactions of organisms. Deficiency of the essential elements may result in malnutrition, impaired body immunity, and poor resistance to disease. These conditions might be enhanced against a background of additional adverse environmental factors such as toxic elements. The analysis of elements in childrens' hair will give information on the deficiency of essential elements and excess of toxic elements in relation to their diet. In this study, 141 hair samples from children (girls and boys) living in two regions of Tanzanian mainlandmore » (Dar es Salaam and Moshi) and the island of Zanzibar have been analysed for trace elements in relation to food consumption habits. The analysis was carried out using long and short irradiation instrumental neutron activation analysis (INAA) of the Nuclear Physics Institute at Rez, Czech Republic. Arithmetic and geometric means with their respective standard deviations are presented for 19 elements. Subgroups were formed according to age, gender, and geographic regions from which the samples were collected. Differences in concentrations for the groups and with other childhood populations were explored and discussed.« less

Biomedical Implications of Heavy Metals Induced Imbalances in Redox Systems

PubMed Central

Singh, Shweta; Siddiqi, Nikhat J.

2014-01-01

Several workers have extensively worked out the metal induced toxicity and have reported the toxic and carcinogenic effects of metals in human and animals. It is well known that these metals play a crucial role in facilitating normal biological functions of cells as well. One of the major mechanisms associated with heavy metal toxicity has been attributed to generation of reactive oxygen and nitrogen species, which develops imbalance between the prooxidant elements and the antioxidants (reducing elements) in the body. In this process, a shift to the former is termed as oxidative stress. The oxidative stress mediated toxicity of heavy metals involves damage primarily to liver (hepatotoxicity), central nervous system (neurotoxicity), DNA (genotoxicity), and kidney (nephrotoxicity) in animals and humans. Heavy metals are reported to impact signaling cascade and associated factors leading to apoptosis. The present review illustrates an account of the current knowledge about the effects of heavy metals (mainly arsenic, lead, mercury, and cadmium) induced oxidative stress as well as the possible remedies of metal(s) toxicity through natural/synthetic antioxidants, which may render their effects by reducing the concentration of toxic metal(s). This paper primarily concerns the clinicopathological and biomedical implications of heavy metals induced oxidative stress and their toxicity management in mammals. PMID:25184144

Pre-ingestive selection capacity and endoscopic analysis in the sympatric bivalves Mulinia edulis and Mytilus chilensis exposed to diets containing toxic and non-toxic dinoflagellates

PubMed Central

Widdows, John; Chaparro, Oscar R.; Ortíz, Alejandro; Mellado, Carla; Villanueva, Paola A.

2018-01-01

This study investigates the effects of toxic and non-toxic dinoflatellates on two sympatric bivalves, the clam Mulinia edulis and the mussel Mytilus chilensis. Groups of bivalves were fed one of three diets: (i) the toxic paralytic shellfish producing (PSP) Alexandrium catenella + Isochrysis galbana; (ii) the non-toxic Alexandrium affine + Isochrysis galbana and (iii) the control diet of Isochrysis galbana. Several physiological traits were measured, such as, clearance rate, pre-ingestive selection efficiency and particle transport velocity in the gill. The clearance rates of both M. chilensis and M. edulis showed a significant reduction when fed a mixed toxic diet of 50% Alexandrium catenella: 50% Isochrysis galbana. Similarly, when both species of bivalves were fed with the non-toxic diet (50% A. affine: 50% I. galbana), clearance rate was significantly lower compared with a diet of 100% I. galbana. Under all the experimental diets, M. chilensis showed higher clearance rate values, slightly more than double that of M. edulis. M. edulis and M. chilensis have the ability to select particles at the pre-ingestive level, thus eliminating a larger proportion of the toxic dinoflagellate A. catenella as well as the non-toxic A. affine in the form of pseudofaeces. Higher values of selection efficiency were registered in M. edulis than in M. chilensis when exposed to the toxic diet. Similar results were observed when these two species were exposed to the diet containing the non-toxic dinoflagellate, explained by the fact that the infaunal Mulinia edulis is adapted to dealing with larger particle sizes and higher particle densities (Navarro et al., 1993). The lower transport particle velocity observed in the present work for both species, is related to the reduced clearance rate, the higher particle concentration, and the presence of larger, toxic dinoflagellates. In addition, the species differ in their feeding responses to diets, with and without A. catenella or A. affine, largely reflecting their adaptations to different environmental conditions. The results suggest that the presence of a dinoflagellate bloom, whether toxic or non-toxic spp in Yaldad Bay, is likely to have a greater impact on the Mytilus chilensis than the infaunal Mulinia edulis, based on the combined effects on clearance rate, selection efficiency and particle transport velocity. PMID:29474467

Pre-ingestive selection capacity and endoscopic analysis in the sympatric bivalves Mulinia edulis and Mytilus chilensis exposed to diets containing toxic and non-toxic dinoflagellates.

PubMed

Navarro, Jorge M; Widdows, John; Chaparro, Oscar R; Ortíz, Alejandro; Mellado, Carla; Villanueva, Paola A

2018-01-01

This study investigates the effects of toxic and non-toxic dinoflatellates on two sympatric bivalves, the clam Mulinia edulis and the mussel Mytilus chilensis. Groups of bivalves were fed one of three diets: (i) the toxic paralytic shellfish producing (PSP) Alexandrium catenella + Isochrysis galbana; (ii) the non-toxic Alexandrium affine + Isochrysis galbana and (iii) the control diet of Isochrysis galbana. Several physiological traits were measured, such as, clearance rate, pre-ingestive selection efficiency and particle transport velocity in the gill. The clearance rates of both M. chilensis and M. edulis showed a significant reduction when fed a mixed toxic diet of 50% Alexandrium catenella: 50% Isochrysis galbana. Similarly, when both species of bivalves were fed with the non-toxic diet (50% A. affine: 50% I. galbana), clearance rate was significantly lower compared with a diet of 100% I. galbana. Under all the experimental diets, M. chilensis showed higher clearance rate values, slightly more than double that of M. edulis. M. edulis and M. chilensis have the ability to select particles at the pre-ingestive level, thus eliminating a larger proportion of the toxic dinoflagellate A. catenella as well as the non-toxic A. affine in the form of pseudofaeces. Higher values of selection efficiency were registered in M. edulis than in M. chilensis when exposed to the toxic diet. Similar results were observed when these two species were exposed to the diet containing the non-toxic dinoflagellate, explained by the fact that the infaunal Mulinia edulis is adapted to dealing with larger particle sizes and higher particle densities (Navarro et al., 1993). The lower transport particle velocity observed in the present work for both species, is related to the reduced clearance rate, the higher particle concentration, and the presence of larger, toxic dinoflagellates. In addition, the species differ in their feeding responses to diets, with and without A. catenella or A. affine, largely reflecting their adaptations to different environmental conditions. The results suggest that the presence of a dinoflagellate bloom, whether toxic or non-toxic spp in Yaldad Bay, is likely to have a greater impact on the Mytilus chilensis than the infaunal Mulinia edulis, based on the combined effects on clearance rate, selection efficiency and particle transport velocity.

Trace element contaminants in mineral fertilizers used in Iran.

PubMed

Latifi, Zahra; Jalali, Mohsen

2018-05-25

The application of mineral fertilizers which have contaminants of trace elements may impose concern regarding the entry and toxic accumulation of these elements in agro-ecosystems. In this study, 57 mineral fertilizers (nitrogen, potassium, phosphate, and compound fertilizers) distributed in Iran were analyzed for their contents of Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, and Fe. The results revealed that the contents of these trace elements varied considerably depending on the type of the element and the fertilizer. Among these elements, Fe displayed the highest average content, whereas Cd showed the lowest. Generally, the trace element contents in P-containing fertilizers were higher than those in nitrogen and potassium fertilizers. The mean values of trace elements (mg kg -1 ) in P-containing fertilizers were 4.0 (Cd), 5.5 (Co), 35.7 (Cr), 24.4 (Cu), 272 (Mn), 14.3 (Ni), 6.0 (Pb), 226 (Zn), and 2532 (Fe). Comparing trace element contents to limit values set by the German Fertilizer Ordinance showed that the mean contents of potentially toxic trace elements, such as Cd and Pb, were lower than their limit values in all groups of fertilizers. On the other hand, while a number of fertilizers contained a high content of some essential trace elements, particularly Fe, they were not labeled as such.

Toxicity of atmospheric aerosols on marine phytoplankton

USGS Publications Warehouse

Paytan, A.; Mackey, K.R.M.; Chen, Y.; Lima, I.D.; Doney, S.C.; Mahowald, N.; Labiosa, R.; Post, A.F.

2009-01-01

Atmospheric aerosol deposition is an important source of nutrients and trace metals to the open ocean that can enhance ocean productivity and carbon sequestration and thus influence atmospheric carbon dioxide concentrations and climate. Using aerosol samples from different back trajectories in incubation experiments with natural communities, we demonstrate that the response of phytoplankton growth to aerosol additions depends on specific components in aerosols and differs across phytoplankton species. Aerosol additions enhanced growth by releasing nitrogen and phosphorus, but not all aerosols stimulated growth. Toxic effects were observed with some aerosols, where the toxicity affected picoeukaryotes and Synechococcus but not Prochlorococcus.We suggest that the toxicity could be due to high copper concentrations in these aerosols and support this by laboratory copper toxicity tests preformed with Synechococcus cultures. However, it is possible that other elements present in the aerosols or unknown synergistic effects between these elements could have also contributed to the toxic effect. Anthropogenic emissions are increasing atmospheric copper deposition sharply, and based on coupled atmosphere-ocean calculations, we show that this deposition can potentially alter patterns of marine primary production and community structure in high aerosol, low chlorophyll areas, particularly in the Bay of Bengal and downwind of South and East Asia.

Sediment Chemistry and Toxicity in Barnegat Bay, New Jersey: Pre- and Post- Hurricane Sandy, 2012-2013.

USGS Publications Warehouse

Romanok, Kristin M.; Szabo, Zoltan; Reilly, Timothy J.; Defne, Zafer; Ganju, Neil K.

2016-01-01

Hurricane Sandy made landfall in Barnegat Bay, October, 29, 2012, damaging shorelines and infrastructure. Estuarine sediment chemistry and toxicity were investigated before and after to evaluate potential environmental health impacts and to establish post-event baseline sediment-quality conditions. Trace element concentrations increased throughout Barnegat Bay up to two orders of magnitude, especially north of Barnegat Inlet, consistent with northward redistribution of silt. Loss of organic compounds, clay, and organic carbon is consistent with sediment winnowing and transport through the inlets and sediment transport modeling results. The number of sites exceeding sediment quality guidance levels for trace elements tripled post-Sandy. Sediment toxicity post-Sandy was mostly unaffected relative to pre-Sandy conditions, but at the site with the greatest relative increase for trace elements, survival rate of the test amphipod decreased (indicating degradation). This study would not have been possible without comprehensive baseline data enabling the evaluation of storm-derived changes in sediment quality.

Linking the occurrence of cutaneous opportunistic fungal invaders with elemental concentrations in false killer whale (Pseudorca crassidens) skin.

PubMed

Mouton, Marnel; Przybylowicz, Wojciech; Mesjasz-Przybylowicz, Jolanta; Postma, Ferdinand; Thornton, Meredith; Archer, Edward; Botha, Alfred

2015-10-01

Cetaceans, occupying the top levels in marine food chains, are vulnerable to elevated levels of potentially toxic trace elements, such as aluminium (Al), mercury (Hg) and nickel (Ni). Negative effects associated with these toxic metals include infection by opportunistic microbial invaders. To corroborate the link between the presence of cutaneous fungal invaders and trace element levels, skin samples from 40 stranded false killer whales (FKWs) were analysed using culture techniques and inductively coupled plasma-mass spectroscopy. Twenty-two skin samples yielded 18 clinically relevant fungal species. While evidence for bioaccumulation of Hg in the skin of the FKWs was observed, a strong link was found to exist between the occurrence of opportunistic fungal invaders and higher Al : Se and Al : Zn ratios. This study provides indications that elevated levels of some toxic metals, such as Al, contribute to immunotoxicity rendering FKWs susceptible to colonization by cutaneous opportunistic fungal invaders. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

Sediment chemistry and toxicity in Barnegat Bay, New Jersey: Pre- and post-Hurricane Sandy, 2012-13.

PubMed

Romanok, Kristin M; Szabo, Zoltan; Reilly, Timothy J; Defne, Zafer; Ganju, Neil K

2016-06-30

Hurricane Sandy made landfall in Barnegat Bay, October, 29, 2012, damaging shorelines and infrastructure. Estuarine sediment chemistry and toxicity were investigated before and after to evaluate potential environmental health impacts and to establish post-event baseline sediment-quality conditions. Trace element concentrations increased throughout Barnegat Bay up to two orders of magnitude, especially north of Barnegat Inlet, consistent with northward redistribution of silt. Loss of organic compounds, clay, and organic carbon is consistent with sediment winnowing and transport through the inlets and sediment transport modeling results. The number of sites exceeding sediment quality guidance levels for trace elements tripled post-Sandy. Sediment toxicity post-Sandy was mostly unaffected relative to pre-Sandy conditions, but at the site with the greatest relative increase for trace elements, survival rate of the test amphipod decreased (indicating degradation). This study would not have been possible without comprehensive baseline data enabling the evaluation of storm-derived changes in sediment quality. Published by Elsevier Ltd.

40 CFR 268.34 - Waste specific prohibitions-toxicity characteristic metal wastes.

Code of Federal Regulations, 2011 CFR

2011-07-01

... characteristic wastes from elemental phosphorus processing; radioactive wastes mixed with EPA Hazardous wastes... identified characteristic wastes from elemental phosphorus processing, radioactive waste mixed with D004-D011...

40 CFR 268.34 - Waste specific prohibitions-toxicity characteristic metal wastes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... characteristic wastes from elemental phosphorus processing; radioactive wastes mixed with EPA Hazardous wastes... identified characteristic wastes from elemental phosphorus processing, radioactive waste mixed with D004-D011...

Elemental distribution patterns in the skins of false killer whales (Pseudorca crassidens) from a mass stranding in South Africa, analysed using micro-PIXE

NASA Astrophysics Data System (ADS)

Mouton, M.; Botha, A.; Thornton, M.; Mesjasz-Przybyłowicz, J.; Przybyłowicz, W. J.

2015-11-01

Several studies revealed that anthropogenic activities often cause toxic concentrations of some elements, such as mercury, which bio-accumulate through the marine food chain, impacting negatively on the health of animals in the top trophic levels, such as a variety of marine mammals. Moreover, analysis of cetacean skin has been reported to be a reliable, long-term and mostly non-invasive method to monitor bio-accumulation of chemicals in cetacean populations. Several elements, including trace elements, occur naturally in cetacean skin, although nothing is known about their distribution patterns and little about safe base line concentrations. In May 2009, 42 false killer whales (FKWs) beached and died at Kommetjie in the Western Cape of South Africa. Skin samples of these FKWs were collected and analysed to determine elemental distribution patterns. The concentrations and distribution patterns of the major, as well as detectable trace elements were determined in skin samples from ten randomly selected FKW individuals, using micro-PIXE (particle-induced X-ray emission) analysis. Results revealed differences between the distribution patterns of elements in the skin sections. Fe, for example, was found to be concentrated in the dermal papillae, whereas the highest Zn concentrations occurred in the epidermis and particularly in the epidermal papillae. Since these essential elements mediate factors such as host immunity, from skin integrity to humoral immunity, knowledge of their typical distribution patterns can be of great value in studies of bio-accumulation. This is the first report of micro-PIXE being employed to study elemental distribution in cetacean skin and the resulting elemental distribution maps can serve as reference in future environmental pollution studies.

Nanoparticles of volcanic ash as a carrier for toxic elements on the global scale.

PubMed

Ermolin, Mikhail S; Fedotov, Petr S; Malik, Natalia A; Karandashev, Vasily K

2018-06-01

At present, there is concern about engineered nanoparticles in the environment, whereas natural nanoparticles (NPs) and their impact are often neglected. In our paper, we demonstrate the important role of nanoparticles of volcanic ash in transport of toxic elements on a global scale. A single volcanic eruption can eject millions of tons of ash. NPs of volcanic ash reach the upper troposphere and the stratosphere and may "travel" around the world for years affecting human health, environment, and even climate. So far, there is a gap in exposure assessment of volcanic ash NPs since their chemical composition remains largely unknown. Here we show for the first time that volcanic ash NPs can serve as an important carrier for potentially toxic elements. The concentrations of Ni, Zn, Cd, Ag, Sn, Se, Te, Hg, Tl, Pb, Bi in volcanic ash NPs (<100 nm) were found to be 10-500 times higher than total contents of these elements in bulk samples. This is valid for volcanoes from different regions of the world (Kamchatka, Far East of Russia and Andes, Chile). The work opens a new door into studies on biogeochemical impact of volcanic ash. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Co-Induced Effects of Molybdenum and Cadmium on the Trace Elements and the mRNA Expression Levels of CP and MT in Duck Testicles.

PubMed

Xia, Bing; Chen, Hua; Hu, Guoliang; Wang, Liqi; Cao, Huabin; Zhang, Caiying

2016-02-01

To investigate the chronic toxicity of molybdenum (Mo) and cadmium (Cd) on the trace elements and the mRNA expression levels of ceruloplasmin (CP) and metallothionein (MT) in duck testicles, 120 healthy 11-day-old male ducks were randomly divided into six groups with 20 ducks in each group. Ducks were treated with the diet containing different dosages of Mo or Cd. The source of Mo and Cd was hexaammonium molybdate ([(NH4)6Mo7O24·4H2O]) and cadmium sulfate (3CdSO4·8H2O), respectively, in this study. After being treated for 60 and 120 days, ten male birds in each group were randomly selected and euthanized and then testicles were aseptically collected for determining the mRNA expression levels of MT and CP, antioxidant indexes, and contents of trace elements in the testicle. In addition, testicle tissues at 120 days were subjected to histopathological analysis with the optical microscope. The results showed that co-exposure to Mo and Cd resulted in an increase in malondialdehyde (MDA) level while decrease in xanthine oxidase (XOD) and catalase (CAT) activities. The mRNA expression level of MT gene was upregulated while CP was decreased in combination groups. Contents of Mo, copper (Cu), iron (Fe), and zinc (Zn) decreased in combined groups while Cd increased in Cd and combined groups at 120 days. Furthermore, severe congestion, low sperm count, and malformation were observed in low dietary of Mo combined with Cd group and high dietary of Mo combined with Cd group. Our results suggested that Mo and Cd might aggravate testicular degeneration synergistically through altering the mRNA expression levels of MT and CP, increasing lipid peroxidation through inhibiting related enzyme activities and disturbing homeostasis of trace elements in testicles. Interaction of Mo and Cd may have a synergistic effect on the testicular toxicity.

Multi-elemental analysis of jet engine lubricating oils and hydraulic fluids and their implication in aircraft air quality incidents.

PubMed

van Netten, C

1999-05-07

The flight crews of aircraft often report symptoms including dizziness, nausea, disorientation, blurred vision and tingling in legs and arms. Many of these incidents have been traced to contamination of cabin air with lubricating oil, as well as hydraulic fluid, constituents. Considering that these air contaminants are often subjected to temperatures in excess of 500 degrees C, a large number of different exposures can be expected. Although the reported symptoms are most consistent with exposures to volatile organic compounds, carbon monoxide, and the organophosphate constituents in these oils and fluids, the involvement of these agents has not been clearly demonstrated. Possible exposure to toxic elements, such as lead, mercury, thallium and others, have not been ruled out. In order to assess the potential of exposure to toxic elements a multi-elemental analysis was done on two hydraulic fluids and three lubricating oils which have been implicated in a number of air quality incidents. A secondary objective was to establish if the multi-elemental concentrations of the fluids tested are different enough to allow such an analysis to be used as a possible method of identifying the source of exposure that might have been present during aircraft air quality incidents. No significant concentrations of toxic elements were identified in any of the oils or hydraulic fluids. The elemental compositions of the samples were different enough to be used for identification purposes and the measurement of only three elements was able to achieve this. Whether these findings have an application, in aircraft air quality incident investigations, needs to be established with further studies.

Functional characterization of replication and stability factors of an incompatibility group P-1 plasmid from Xylella fastidiosa.

PubMed

Lee, Min Woo; Rogers, Elizabeth E; Stenger, Drake C

2010-12-01

Xylella fastidiosa strain riv11 harbors a 25-kbp plasmid (pXF-RIV11) belonging to the IncP-1 incompatibility group. Replication and stability factors of pXF-RIV11 were identified and used to construct plasmids able to replicate in X. fastidiosa and Escherichia coli. Replication in X. fastidiosa required a 1.4-kbp region from pXF-RIV11 containing a replication initiation gene (trfA) and the adjacent origin of DNA replication (oriV). Constructs containing trfA and oriV from pVEIS01, a related IncP-1 plasmid of the earthworm symbiont Verminephrobacter eiseniae, also were competent for replication in X. fastidiosa. Constructs derived from pXF-RIV11 but not pVEIS01 replicated in Agrobacterium tumefaciens, Xanthomonas campestris, and Pseudomonas syringae. Although plasmids bearing replication elements from pXF-RIV11 or pVEIS01 could be maintained in X. fastidiosa under antibiotic selection, removal of selection resulted in plasmid extinction after 3 weekly passages. Addition of a toxin-antitoxin addiction system (pemI/pemK) from pXF-RIV11 improved plasmid stability such that >80 to 90% of X. fastidiosa cells retained plasmid after 5 weekly passages in the absence of antibiotic selection. Expression of PemK in E. coli was toxic for cell growth, but toxicity was nullified by coexpression of PemI antitoxin. Deletion of N-terminal sequences of PemK containing the conserved motif RGD abolished toxicity. In vitro assays revealed a direct interaction of PemI with PemK, suggesting that antitoxin activity of PemI is mediated by toxin sequestration. IncP-1 plasmid replication and stability factors were added to an E. coli cloning vector to constitute a stable 6.0-kbp shuttle vector (pXF20-PEMIK) suitable for use in X. fastidiosa.

Profiling extractable and leachable inorganic impurities in ophthalmic drug containers by ICP-MS.

PubMed

Solomon, Paige; Nelson, Jenny

2018-03-01

In this study, we investigated the elemental impurities present in the plastic material of ophthalmic eye drop bottles using inductively coupled plasma-mass spectrometry (ICP-MS). Metallic contaminations, especially localized within the small cavity of the eye, can significantly perturb the ocular metallome. The concern is two-fold: first certain elements, for example heavy metals, can be toxic to humans at even trace levels, and second, these contaminations can have adverse reactions with other medicines or enzymatic processes in the eye. The implication of redox-active metals in cataract formation is one such biological consequence. The analysis demonstrated the effect of aggressive storage and transportation conditions on elemental extractable and leachable contamination, and posits that release of these elemental impurities can disrupt metallome equilibrium in the ocular compartment, leading to toxicity and disease.

Toxic and essential elements in Lebanese cheese.

PubMed

Bou Khozam, Rola; Pohl, Pawel; Al Ayoubi, Baydaa; Jaber, Farouk; Lobinski, Ryszard

2012-01-01

Concentrations of 20 minor, trace and ultratrace elements relevant to human health (Ag, Al, As, Cd, Co, Cr, Cu, Fe, Hg, Li, Mn, Mo, Ni, Pb, Sb, Se, Si, Sn, V) were determined in four different varieties of the most consumed cheese in Lebanon (Halloumi, Double Crème, Baladi, Labneh) sampled at five different provinces (Grand Beirut, South of Lebanon, North of Lebanon, Mount of Lebanon and Beka'a) during the wet and dry seasons. The analyses were carried out by double focussing sector field inductively coupled plasma-mass spectrometry (ICP-MS) in order to avoid errors due to polyatomic interferences. Levels of toxic elements (As, Cd, Pb) were generally below the WHO permissible levels in dairy products. Concentrations of most elements were considerably affected by the type of cheese, the geographical site and the season of sampling.

Estimated Dietary Intakes of Toxic Elements from Four Staple Foods in Najran City, Saudi Arabia.

PubMed

Mohamed, Hatem; Haris, Parvez I; Brima, Eid I

2017-12-14

Exposure of the inhabitants of Najran area in Saudi Arabia to the toxic elements As, Cd, Cr, and Pb through foods has not been previously investigated. Exposure to such elements is an important public health issue, so the study described here was performed with the aim of determining estimated dietary intakes (EDIs) for these metals in Najran area. The As, Cd, Cr, and Pb concentrations in four staple foods (rice, wheat, red meat, and chicken) were determined by inductively coupled plasma-mass spectrometry. A food frequency questionnaire (FFQ) was completed by 80 study participants. These data were used to estimate dietary intakes of the metals in the four staple foods. The mean As, Cd, Cr, and Pb EDIs in the four food types were 1.1 × 10 -6 -2.6 × 10 -5 , 1.42 × 10 -5 -2.2 × 10 -4 , 3.4 × 10 -4 -8.0 × 10 -4 , and 2.3 × 10 -5 -2.1 × 10 -3 mg/kg bw day, respectively. Hazard Quotients (HQ) for all elements did not exceed one. The highest Pb concentration was found for chicken and the source of this toxic element in this food needs to be investigated in the future. The lowest As concentration was found for wheat highest in rice. The EDIs for all elements in the four food types were below the provisional tolerable weekly intakes set by the World Health Organization (WHO).

Toxic effects of selenium and copper on the planarian, Dugesia dorotocephala

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

Rauscher, J.D.

1988-01-01

Aquatic toxicologists have become increasingly concerned with the effects of sublethal concentrations of toxicants on aquatic organisms. Sublethal effects of toxicants on freshwater invertebrates were reviewed. Selenium (Se) and copper (Cu) are both essential trace elements and toxicants. Se has been reported to alter the toxicity of heavy metals. Planarians, Dugesia dorotocephala, were used as test animals. The objectives of this study were to determine: (1) acute toxicity of Se on planarians and the effect of the number of planarians per test chamber, (2) interaction of the acute toxicity of Se and Cu on planarians, and (3) sublethal effects ofmore » Se and Cu on planarians.« less

Heavy Metals Toxicity and the Environment

PubMed Central

Tchounwou, Paul B; Yedjou, Clement G; Patlolla, Anita K; Sutton, Dwayne J

2013-01-01

Heavy metals are naturally occurring elements that have a high atomic weight and a density at least 5 times greater than that of water. Their multiple industrial, domestic, agricultural, medical and technological applications have led to their wide distribution in the environment; raising concerns over their potential effects on human health and the environment. Their toxicity depends on several factors including the dose, route of exposure, and chemical species, as well as the age, gender, genetics, and nutritional status of exposed individuals. Because of their high degree of toxicity, arsenic, cadmium, chromium, lead, and mercury rank among the priority metals that are of public health significance. These metallic elements are considered systemic toxicants that are known to induce multiple organ damage, even at lower levels of exposure. They are also classified as human carcinogens (known or probable) according to the U.S. Environmental Protection Agency, and the International Agency for Research on Cancer. This review provides an analysis of their environmental occurrence, production and use, potential for human exposure, and molecular mechanisms of toxicity, genotoxicity, and carcinogenicity. PMID:22945569

The test ability of fish Tawes to leachate garbage dump (TPA) Benowo

NASA Astrophysics Data System (ADS)

Juliardi AR, N. R.; Wiyanti, R. I.

2018-01-01

Leachate is a liquid from waste containing elements of dissolved and suspended elements. Garbage collected at the landfill site contains organic, inorganic and heavy metal substances. If the rains will produce leachate with mineral content, organic and heavy metals. When the condition or leachate flow in let to the soil surface can cause negative effects to the surrounding environment including for humans. Toxicity test it was conducted to determine the level of leachate toxicity of the test animals living in surface water located around of the “TPA Benowo”. In this study using Tawes fish with length between 4-6 cm. In this toxicity test is done in 2 stages, namely: range finding test, the search for this range is obtained 0% concentrations (as control) 0,3%; 0,6%; 0,9%; 0,12% and 0,15%. The next stage of toxicity acute test, at this stage of toxicity concentration do smaller again that is: 0,18%; 0,36%; 0,54%; 0,72% and 0,9%. The results obtained LC50 value of 0,385%, while eyes, brown stomach skin.

TEMPORAL VARIABILITY OF TOXIC CONTAMINANTS IN ANIMAL DIETS

EPA Science Inventory

Uncertified commercial research animal feed (Purina Chow TM) was analyzed over forty-one months to determine essential and trace elements and toxic contaminants. Parametric statistics and graphic chronologic progressions of the results are presented for cat, monkey, rodent (rat/m...

Analysis of four toxic metals in a single rice seed by matrix solid phase dispersion -inductively coupled plasma mass spectrometry

NASA Astrophysics Data System (ADS)

He, Xiufen; Chen, Lixia; Chen, Xin; Yu, Huamei; Peng, Lixu; Han, Bingjun

2016-12-01

Toxic metals in rice pose great risks to human health. Metal bioaccumulation in rice grains is a criterion of breeding. Rice breeding requires a sensitive method to determine metal content in single rice grains to assist the variety selection. In the present study, four toxic metals of arsenic (As), cadmium (Cd), chromium (Cr) and lead (Pb) in a single rice grain were determined by a simple and rapid method. The developed method is based on matrix solid phase dispersion using multi-wall carbon nanotubes (MWCNTs) as dispersing agent and analyzed by inductively coupled plasma mass spectrometry. The experimental parameters were systematically investigated. The limits of detection (LOD) were 5.0, 0.6, 10 and 2.1 ng g-1 for As, Cd, Cr, and Pb, respectively, with relative standard deviations (n = 6) of <7.7%, demonstrating the good sensitivity and precision of the method. The results of 30 real world rice samples analyzed by this method agreed well with those obtained by the standard microwave digestion. The amount of sample required was reduced approximately 100 fold in comparison with the microwave digestion. The method has a high application potential for other sample matrices and elements with high sensitivity and sample throughput.

Current data regarding the structure-toxicity relationship of boron-containing compounds.

PubMed

Farfán-García, E D; Castillo-Mendieta, N T; Ciprés-Flores, F J; Padilla-Martínez, I I; Trujillo-Ferrara, J G; Soriano-Ursúa, M A

2016-09-06

Boron is ubiquitous in nature, being an essential element of diverse cells. As a result, humans have had contact with boron containing compounds (BCCs) for a long time. During the 20th century, BCCs were developed as antiseptics, antibiotics, cosmetics and insecticides. Boric acid was freely used in the nosocomial environment as an antiseptic and sedative salt, leading to the death of patients and an important discovery about its critical toxicology for humans. Since then the many toxicological studies done in relation to BCCs have helped to establish the proper limits of their use. During the last 15 years, there has been a boom of research on the design and use of new, potent and efficient boron containing drugs, finding that the addition of boron to some known drugs increases their affinity and selectivity. This mini-review summarizes two aspects of BCCs: toxicological data found with experimental models, and the scarce but increasing data about the structure-activity relationship for toxicity and therapeutic use. As is the case with boron-free compounds, the biological activity of BCCs is related to their chemical structure. We discuss the use of new technology to discover potent and efficient BCCs for medicinal therapy by avoiding toxic effects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Analysis of four toxic metals in a single rice seed by matrix solid phase dispersion -inductively coupled plasma mass spectrometry.

PubMed

He, Xiufen; Chen, Lixia; Chen, Xin; Yu, Huamei; Peng, Lixu; Han, Bingjun

2016-12-06

Toxic metals in rice pose great risks to human health. Metal bioaccumulation in rice grains is a criterion of breeding. Rice breeding requires a sensitive method to determine metal content in single rice grains to assist the variety selection. In the present study, four toxic metals of arsenic (As), cadmium (Cd), chromium (Cr) and lead (Pb) in a single rice grain were determined by a simple and rapid method. The developed method is based on matrix solid phase dispersion using multi-wall carbon nanotubes (MWCNTs) as dispersing agent and analyzed by inductively coupled plasma mass spectrometry. The experimental parameters were systematically investigated. The limits of detection (LOD) were 5.0, 0.6, 10 and 2.1 ng g -1 for As, Cd, Cr, and Pb, respectively, with relative standard deviations (n = 6) of <7.7%, demonstrating the good sensitivity and precision of the method. The results of 30 real world rice samples analyzed by this method agreed well with those obtained by the standard microwave digestion. The amount of sample required was reduced approximately 100 fold in comparison with the microwave digestion. The method has a high application potential for other sample matrices and elements with high sensitivity and sample throughput.

Abiotic Stress Response to As and As+Si, Composite Reprogramming of Fruit Metabolites in Tomato Cultivars

PubMed Central

Marmiroli, Marta; Mussi, Francesca; Imperiale, Davide; Lencioni, Giacomo; Marmiroli, Nelson

2017-01-01

The toxic element arsenic interacts with the beneficial element silicon at many levels of the plant metabolism. The ability of the tomato plant to take up and translocate As into its fruit has risen concerns that it could facilitate the entry of this element into the human food chain above the admitted level. Here, the fruit of two contrasting tomato cultivars, Aragon and Gladis, were evaluated following exposures of either 48 h or 14 days to As-contaminated irrigation water, with or without supplementary Si. The focus was on selected biochemical stress response indicators to dissect metabolic fruit reprogramming induced by As and Si. A multivariate statistical approach was utilized to establish the relationship between tissue As and Si concentrations and selected biochemical aspects of the stress response mechanisms to identify a set of relevant stress response descriptors. This resulted in the recognition of strong cultivar and temporal effects on metabolic and biochemical stress parameters following the treatments. In this paper the metabolic changes in H2O2 content, lipid peroxidation, lycopene and carotenoids content, ascorbate and GSH redox state, total phenolics, ABTS and DPPH radicals inhibition were in favor of an oxidative stress. The significance of some of these parameters as reliable arsenic exposition biomarkers is discussed in the context of the limited knowledge on the As-induced stress response mechanisms at the level of the ripening fruit which presents a distinctive molecular background dissimilar from roots and shoots. PMID:29312426

Analysis of 22 Elements in Milk, Feed, and Water of Dairy Cow, Goat, and Buffalo from Different Regions of China.

PubMed

Zhou, Xuewei; Qu, Xueyin; Zhao, Shengguo; Wang, Jiaqi; Li, Songli; Zheng, Nan

2017-03-01

The objectives of this study were to measure the concentrations of elements in raw milk by inductively coupled plasma-mass spectrometry (ICP-MS) and evaluate differences in element concentrations among animal species and regions of China. Furthermore, drinking water and feed samples were analyzed to investigate whether the element concentrations in raw milk are correlated with those in water and feed. All samples were analyzed by ICP-MS following microwave-assisted acid digestion. The mean recovery of the elements was 98.7 % from milk, 103.7 % from water, and 93.3 % from a certified reference material (cabbage). Principal component analysis results revealed that element concentrations differed among animal species and regions. Correlation analysis showed that trace elements Mn, Fe, Ni, Ga, Se, Sr, Cs, U in water and Co, Ni, Cu, Se, U in feed were significantly correlated with those in milk (p < 0.05). Toxic and potential toxic elements Cr, As, Cd, Tl, Pb in water and Al, Cr, As, Hg, Tl in feed were significantly correlated with those in milk (p < 0.05). Results of correlation analysis revealed that elements in water and feed might contribute to the elements in milk.

Essential and toxic element concentrations in blood and urine and their associations with diet: results from a Norwegian population study including high-consumers of seafood and game.

PubMed

Birgisdottir, B E; Knutsen, H K; Haugen, M; Gjelstad, I M; Jenssen, M T S; Ellingsen, D G; Thomassen, Y; Alexander, J; Meltzer, H M; Brantsæter, A L

2013-10-01

The first aim of the study was to evaluate calculated dietary intake and concentrations measured in blood or urine of essential and toxic elements in relation to nutritional and toxicological reference values. The second aim was to identify patterns of the element concentrations in blood and urine and to identify possible dietary determinants of the concentrations of these elements. Adults with a known high consumption of environmental contaminants (n=111), and a random sample of controls (n=76) answered a validated food frequency questionnaire (FFQ). Complete data on biological measures were available for 179 individuals. Blood and urine samples were analyzed for selenium, iodine, arsenic, mercury, cadmium and lead. Principal component analysis was used to identify underlying patterns of correlated blood and urine concentrations. The calculated intakes of selenium, iodine, inorganic arsenic and mercury were within guideline levels. For cadmium 24% of the high consumer group and 8% of the control group had intakes above the tolerable weekly intake. Concentrations of lead in blood exceeded the bench-mark dose lower confidence limits for some participants. However, overall, the examined exposures did not give rise to nutritional or toxicological concerns. Game consumption was associated with lead in blood (B(ln) 0.021; 95%CI:0.010, 0.031) and wine consumption. Seafood consumption was associated with urinary cadmium in non-smokers (B(ln) 0.009; 95%CI:0.003, 0.015). A novel finding was a distinct pattern of positively associated biological markers, comprising iodine, selenium, arsenic and mercury (eigenvalue 3.8), reflecting seafood intake (B 0.007; 95%CI:0.004, 0.010). The study clearly demonstrates the significance of seafood as a source of both essential nutrients and toxic elements simultaneously and shows that exposure to various essential and toxic elements can be intertwined. © 2013 Elsevier B.V. All rights reserved.

Several methods to determine heavy metals in the human brain

NASA Astrophysics Data System (ADS)

Andrási, Erzsébet; Igaz, Sarolta; Szoboszlai, Norbert; Farkas, Éva; Ajtony, Zsolt

1999-05-01

The determination of naturally occurring heavy metals in various parts of the human brain is discussed. The patients had no diseases in their central nervous systems (five individuals, mean age 70 years). Twenty brain parts were selected from both hemispheres. The analysis was carried out by graphite furnace atomic absorption spectrometry, inductively coupled plasma atomic emission spectrometry and instrumental neutron activation analysis methods. Accuracy and precision of the applied techniques were tested by using standard reference materials. Two digestion methods were used to dissolve the brain samples for ICP-AES and GF-AAS. One was performed in a Parr-bomb and the second in a microwave oven. The present results show a non-homogeneous distribution of the essential elements (Cu, Fe, Mn, Zn) in normal human brain. Corresponding regions in both hemispheres showed an almost identical concentration of these elements. In the case of toxic elements (Pb, Cd) an average value in different brain regions can not be established because of the high variability of individual data. This study indicates that beside differences in Pb and Cd intake with foods or cigarette smoke inhalation, the main factors of the high inter-individual variability of these element concentrations in human brain parts may be a marked difference in individual elimination or accumulation capabilities.

Cytotoxicity and therapeutic effect of irinotecan combined with selenium nanoparticles.

PubMed

Gao, Fuping; Yuan, Qing; Gao, Liang; Cai, Pengju; Zhu, Huarui; Liu, Ru; Wang, Yaling; Wei, Yueteng; Huang, Guodong; Liang, Jian; Gao, Xueyun

2014-10-01

Although chemotherapeutic drugs are widely applied for clinic tumor treatment, severe toxicity restricts their therapeutic efficacy. In this study, we reported a new form of selenium, selenium nanoparticles (Nano Se) which have significant lower toxicity and acceptable bioavailability. We investigated Nano Se as chemotherapy preventive agent to protect against toxicities of anticancer drug irinotecan and synergistically enhance the anti-tumor treatment effect in vitro and in vivo. The underlying mechanisms were also investigated. The combination of Nano Se and irinotecan showed increased cytotoxic effect with HCT-8 tumor cells likely by p53 mediated apoptosis. Nano Se inhibited growth of HCT-8 tumor cells partially through caspases mediated apoptosis. In vivo experiment showed Nano Se at a dose of 4 mg/kg/day significantly alleviated adverse effects induced by irinotecan (60 mg/kg) treatment. Nano Se alone treatment did not induce any toxic manifestations. The combination of Nano Se and irinotecan dramatically inhibited tumor growth and significantly induced apoptosis of tumor cells in HCT-8 cells xenografted tumor. Tumor inhibition rate was about 17.2%, 48.6% and 62.1% for Nano Se, irinotecan and the combination of Nano Se and irinotecan, respectively. The beneficial effects of Nano Se for tumor therapy were mainly ascribed to selectively regulating Nrf2-ARE (antioxidant responsive elements) pathway in tumor tissues and normal tissues. Our results suggest Nano Se is a promising selenium species with potential application in cancer treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Lead, cadmium and other metals in serum of pet dogs from an urban area of NW Poland.

PubMed

Tomza-Marciniak, Agnieszka; Pilarczyk, Bogumiła; Bąkowska, Małgorzata; Ligocki, Marek; Gaik, Marcelina

2012-12-01

This study was designed to evaluate the degree of exposure of pet dogs from an urban area of NW Poland to selected metals, including toxic Cd and Pb. The study was conducted on a group of 48 healthy dogs. The serum concentration of the analysed elements followed the order Fe > Al > Zn > Cu > Mn > As > Sr > Pb > Cd > Cr > Ni > V. The presence of cadmium and lead was found in all the serum samples tested. The average contents of these elements were 0.309 and 0.489 μg/mL. The factors that played the greatest role in the intake of the analysed elements were diet and breed-dependent size of dogs. Small-sized dogs had higher concentrations of all elements compared with large dogs, with statistically significant differences noted for Cu, Pb, Cd and Sr. It was also found that dogs receiving commercial and mixed food had more metals in serum compared with dogs on homemade food (except strontium). The present study showed elevated concentrations of some heavy metals (Pb, Cd, Fe and Cu) in serum of pet dogs, which is probably due to the excess elemental load of this area. Given that no information is available on the concentrations of strontium, vanadium and aluminium in dogs, further research is necessary to determine certain reference values which would allow for an easier interpretation of results and evaluation of exposure to these elements.

Comparison of essential and toxic elements in esophagus, lung, mouth and urinary bladder male cancer patients with related to controls.

PubMed

Kazi, Tasneem Gul; Wadhwa, Sham Kumar; Afridi, Hassan Imran; Talpur, Farah Naz; Tuzen, Mustafa; Baig, Jameel Ahmed

2015-05-01

There is a compelling evidence in support of negative associations between essential trace and toxic elements in different types of cancer. The aim of the present study was to investigate the relationship between carcinogenic (As, Cd, Ni) and anti-carcinogenic (Se, Zn) trace elements in scalp hair samples of different male cancerous patients (esophagus, lung, mouth, and urinary bladder). For comparative purposes, the scalp hair samples of healthy males of the same age group (ranged 35-65 years) as controls were analyzed. Both controls and patients have the same socioeconomic status, localities, dietary habits, and smoking locally made cigarette. The scalp hair samples were oxidized by 65% nitric acid: 30% hydrogen peroxide (2:1) ratio in microwave oven followed by atomic absorption spectrometry. The validity and accuracy of the methodology were checked using certified reference material of human hair BCR 397. The mean concentrations of As, Cd, and Ni were found to be significantly higher in scalp hair samples of patients having different cancers as compared to the controls, while reverse results were obtained in the case of Se and Zn levels (p < 0.01). The study revealed that the carcinogenic processes are significantly affecting the trace elements burden and mutual interaction of essential trace and toxic elements in the cancerous patients.

In which regions is breast-feeding safer from the impact of toxic elements from the environment?

PubMed

Cinar, Nursan; Ozdemir, Sami; Yucel, Oya; Ucar, Fatma

2011-11-01

Owing to its unique nutritional and immunological characteristics, breast milk is the most important food source for infants. But, children are at greater risk for exposure to environmental toxicants from breast milk. The aim of this study was to evaluate the influence of environmental pollution on essential and toxic element contents of breast milk and determine the risky locations in our population. This study was conducted on women who were breastfeeding (n=90). Milk samples were collected at three locations in Marmara region, Turkey: highly industrialized region highly affected by pollution, urbanized region moderately and rural area that is affected little. Breast milk samples (5 mL) were collected at approximately one month postpartum (mature milk). The concentrations of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) in milk samples were compared to the milk samples coming from different locations.Lead, cadmium, nickel, chromium, iron and manganese levels in the breast milk are highest and engrossing especially in rural areas compared to the other regions but cobalt, copper, zinc levels are highest in highly industrial areas. The levels of essential and toxic elements in breast milk can vary in different regions. The levels presented in our study are above some countries' data albeit not at toxic levels. Because of global effects, environmental pollution is not the problem for industrializing regions only. Rural area also may not be safe for breastfeed babies.

ELEMENTAL SPECIATION IN ENVIRONMENTAL EXPOSURE ASSESSMENT MATRICES

EPA Science Inventory

Arsenic and tin are two trace metals where exposure assessments have moved towards a speciation based approach because the toxicity is very chemical form dependent. This toxicity difference can be one of many factors which influence the formulation of certain regulations. For a...

Evolution of thiol protective systems in prokaryotes

NASA Technical Reports Server (NTRS)

Fahey, R. C.; Newton, G. L.

1986-01-01

Biological thiols are essential elements in most aspects of cell function but undergo rapid oxidation to disulfides in the presence of oxygen. The evolution of systems to protect against such oxygen toxicity was essential to the emergence of aerobic life. The protection system used by eukaryotes is based upon glutathione (GSH) and GSH-dependent enzymes but many bacteria lack GSH and apparently use other mechanisms. The objective of this research is to elaborate the thiol protective mechanisms employed by prokaryotes of widely divergent evolutionary origin and to understand why GSH became the central thiol employed in essentially all higher organisms. Thiol-selective fluorescent labeling and HPLC analysis has been used to determine key monothiol components.

Mercury, elemental

Integrated Risk Information System (IRIS)

Mercury , elemental ; CASRN 7439 - 97 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

Premature aging in bone of fish from a highly polluted marine area.

PubMed

Scopelliti, Giovanna; Di Leonardo, Rossella; Tramati, Cecilia D; Mazzola, Antonio; Vizzini, Salvatrice

2015-08-15

Fish species have attracted considerable interest in studies assessing biological responses to environmental contaminants. In this study, the attention has been focussed on fishbone of selected fish species from a highly polluted marine area, Augusta Bay (Italy, Central Mediterranean) to evaluate if toxicant elements had an effect on the mineralogical structure of bones, although macroscopic deformations were not evident. In particular, an attempt was made to evaluate if bone mineral features, such as crystallinity, mineral maturity and carbonate/phosphate mineral content, determined by XR-Diffraction and FT-IR Spectroscopy, suffered negative effects due to trace element levels in fishbone, detected by ICP-OES. Results confirmed the reliability of the use of diffractometric and spectroscopic techniques to assess the degree of crystallinity and the mineral maturity in fishbone. In addition, in highly polluted areas, Hg and Cr contamination induced a process of premature aging of fishbone, altering its biochemical and mineral contents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Trace elements in oceanic pelagic communities in the western Indian Ocean.

PubMed

Bodin, Nathalie; Lesperance, Dora; Albert, Rona; Hollanda, Stephanie; Michaud, Philippe; Degroote, Maxime; Churlaud, Carine; Bustamante, Paco

2017-05-01

The mineral composition of target and non-target pelagic fish caught by purse-seiners and longliners in the western-central Indian Ocean was determined. From the 10 essential elements analysed, selenium and zinc showed the highest concentrations in swordfish and blue marlin while Indian mackerel appeared as a good source of copper, iron and chrome. All catch had levels of lead and cadmium, two toxic elements, below the maximum sanitary limits. Although some concerns were raised regarding mercury concentrations in the largest species (wahoo, swordfish and blue marlin), molar ratios of mercury and selenium indicate that all oceanic pelagic fish from the western-central Indian Ocean are safe for human consumption. This study also gives insights on the relationships between the levels of essential and toxic elements in fish muscle and the size, trophic position and diet sources of the studied pelagic species. Copyright © 2017 Elsevier Ltd. All rights reserved.

Essentiality, Toxicity and Uncertainty in the Risk Assessment of Manganese

EPA Science Inventory

Risk assessments of manganese by inhalation or oral routes of exposure typically acknowledge the duality of manganese as an essential element at low doses and a toxic metal at high doses. Previously, however, risk assessors were unable to describe manganese pharmacokinetics quant...

Survey of toxicity and carcinogenity of mineral deposits

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

Furst, A.; Harding-Barlow, I.

1981-11-03

The toxicities and biogeochemical cycles of arsenic, cadmium, chromium, lead and nickel are reviewed in some detail, and other trace elements briefly mentioned. These heavy metals are used as a framework within which the problem of low-level radioactive waste disposal can be compared. (ACR)

Pollution Assessment of Toxic and Potentially Toxic Elements in Agricultural Soils of the City Addis Ababa, Ethiopia.

PubMed

Aschale, Minbale; Sileshi, Yilma; Kelly-Quinn, Mary; Hailu, Dereje

2017-02-01

Due to the significantly fast urban expansion and increased industrial activities, the soils in the farms in Addis Ababa are contaminated by some toxic and potentially toxic elements (As, V, Cr, Fe, Co, Ni, Cu, B, Ba, Sr, Zn, Mn, Pb and Cd) in varying degrees. The mean concentrations of Cr, Ni, As and B in most of the soil farms were found to be higher than the maximum recommended limits. The mean concentrations of Cd, Cu, Pb, Co, Ni and Mn were found to be higher than the background soil concentrations given for uncontaminated soils. Multivariate analyses coupled with correlation analysis were used to identify possible sources. The geo-accumulation index values for Cr, Mn and Pb indicated that the farm soils were unpolluted to moderately polluted as a result of anthropogenic activities. A comprehensive environmental management strategy should be formulated by the government to measure further pollution of the farmland soil.

An evaluation of inorganic toxicity reference values for use in assessing hazards to American robins (Turdus migratorius).

PubMed

Beyer, W Nelson; Sample, Bradley E

2017-03-01

When performing screening-level and baseline risk assessments, assessors usually compare estimated exposures of wildlife receptor species with toxicity reference values (TRVs). We modeled the exposure of American robins (Turdus migratorius) to 10 elements (As, Cd, Cr, Cu, Hg, Mn, Pb, Se, Zn, and V) in spring and early summer, a time when earthworms are the preferred prey. We calculated soil benchmarks associated with possible toxic effects to these robins from 6 sets of published TRVs. Several of the resulting soil screening-level benchmarks were inconsistent with each other and less than soil background concentrations. Accordingly, we examined the derivations of the TRVs as a possible source of error. In the case of V, a particularly toxic chemical compound (ammonium vanadate) containing V, not normally present in soil, had been used to estimate a TRV. In the cases of Zn and Cu, use of uncertainty values of 10 in estimating TRVs led to implausibly low soil screening values. In the case of Pb, a TRV was calculated from studies demonstrating reductions in egg production in Japanese quail (Coturnix coturnix japonica) exposed to Pb concentrations well below than those causing toxic effects in other species of birds. The results on quail, which were replicated in additional trials, are probably not applicable to other, unrelated species, although we acknowledge that only a small fraction of all species of birds has been tested. These examples underscore the importance of understanding the derivation and relevance of TRVs before selecting them for use in screening or in ecological risk assessment. Integr Environ Assess Manag 2017;13:352-359. © 2016 SETAC. © 2016 SETAC.

"Watching the Detectives" report of the general assembly of the EU project DETECTIVE Brussels, 24-25 November 2015.

PubMed

Fernando, Ruani N; Chaudhari, Umesh; Escher, Sylvia E; Hengstler, Jan G; Hescheler, Jürgen; Jennings, Paul; Keun, Hector C; Kleinjans, Jos C S; Kolde, Raivo; Kollipara, Laxmikanth; Kopp-Schneider, Annette; Limonciel, Alice; Nemade, Harshal; Nguemo, Filomain; Peterson, Hedi; Prieto, Pilar; Rodrigues, Robim M; Sachinidis, Agapios; Schäfer, Christoph; Sickmann, Albert; Spitkovsky, Dimitry; Stöber, Regina; van Breda, Simone G J; van de Water, Bob; Vivier, Manon; Zahedi, René P; Vinken, Mathieu; Rogiers, Vera

2016-06-01

SEURAT-1 is a joint research initiative between the European Commission and Cosmetics Europe aiming to develop in vitro- and in silico-based methods to replace the in vivo repeated dose systemic toxicity test used for the assessment of human safety. As one of the building blocks of SEURAT-1, the DETECTIVE project focused on a key element on which in vitro toxicity testing relies: the development of robust and reliable, sensitive and specific in vitro biomarkers and surrogate endpoints that can be used for safety assessments of chronically acting toxicants, relevant for humans. The work conducted by the DETECTIVE consortium partners has established a screening pipeline of functional and "-omics" technologies, including high-content and high-throughput screening platforms, to develop and investigate human biomarkers for repeated dose toxicity in cellular in vitro models. Identification and statistical selection of highly predictive biomarkers in a pathway- and evidence-based approach constitute a major step in an integrated approach towards the replacement of animal testing in human safety assessment. To discuss the final outcomes and achievements of the consortium, a meeting was organized in Brussels. This meeting brought together data-producing and supporting consortium partners. The presentations focused on the current state of ongoing and concluding projects and the strategies employed to identify new relevant biomarkers of toxicity. The outcomes and deliverables, including the dissemination of results in data-rich "-omics" databases, were discussed as were the future perspectives of the work completed under the DETECTIVE project. Although some projects were still in progress and required continued data analysis, this report summarizes the presentations, discussions and the outcomes of the project.

“Watching the Detectives” Report of the general assembly of the EU project DETECTIVE Brussels, 24-25 November, 2015

PubMed Central

Fernando, Ruani N.; Chaudhari, Umesh; Escher, Sylvia E.; Hengstler, Jan G.; Hescheler, Jürgen; Jennings, Paul; Keun, Hector C.; Kleinjans, Jos C. S.; Kolde, Raivo; Kollipara, Laxmikanth; Kopp-Schneider, Annette; Limonciel, Alice; Nemade, Harshal; Nguemo, Filomain; Peterson, Hedi; Prieto, Pilar; Rodrigues, Robim M.; Sachinidis, Agapios; Schäfer, Christoph; Sickmann, Albert; Spitkovsky, Dimitry; Stöber, Regina; van Breda, Simone G.J.; van de Water, Bob; Vivier, Manon; Zahedi, René P.

2017-01-01

SEURAT-1 is a joint research initiative between the European Commission and Cosmetics Europe aiming to develop in vitro and in silico based methods to replace the in vivo repeated dose systemic toxicity test used for the assessment of human safety. As one of the building blocks of SEURAT-1, the DETECTIVE project focused on a key element on which in vitro toxicity testing relies: the development of robust and reliable, sensitive and specific in vitro biomarkers and surrogate endpoints that can be used for safety assessments of chronically acting toxicants, relevant for humans. The work conducted by the DETECTIVE consortium partners has established a screening pipeline of functional and “-omics” technologies, including high-content and high-throughput screening platforms, to develop and investigate human biomarkers for repeated dose toxicity in cellular in vitro models. Identification and statistical selection of highly predictive biomarkers in a pathway- and evidence-based approach constitutes a major step in an integrated approach towards the replacement of animal testing in human safety assessment. To discuss the final outcomes and achievements of the consortium, a meeting was organized in Brussels. This meeting brought together data-producing and supporting consortium partners. The presentations focused on the current state of ongoing and concluding projects and the strategies employed to identify new relevant biomarkers of toxicity. The outcomes and deliverables, including the dissemination of results in data-rich “-omics” databases, were discussed as were the future perspectives of the work completed under the DETECTIVE project. Although some projects were still in progress and required continued data analysis, this report summarizes the presentations, discussions and the outcomes of the project. PMID:27129694

Human placenta processed for encapsulation contains modest concentrations of 14 trace minerals and elements.

PubMed

Young, Sharon M; Gryder, Laura K; David, Winnie B; Teng, Yuanxin; Gerstenberger, Shawn; Benyshek, Daniel C

2016-08-01

Maternal placentophagy has recently emerged as a rare but increasingly popular practice among women in industrialized countries who often ingest the placenta as a processed, encapsulated supplement, seeking its many purported postpartum health benefits. Little scientific research, however, has evaluated these claims, and concentrations of trace micronutrients/elements in encapsulated placenta have never been examined. Because the placenta retains beneficial micronutrients and potentially harmful toxic elements at parturition, we hypothesized that dehydrated placenta would contain detectable concentrations of these elements. To address this hypothesis, we analyzed 28 placenta samples processed for encapsulation to evaluate the concentration of 14 trace minerals/elements using inductively coupled plasma mass spectrometry. Analysis revealed detectable concentrations of arsenic, cadmium, cobalt, copper, iron, lead, manganese, mercury, molybdenum, rubidium, selenium, strontium, uranium, and zinc. Based on one recommended daily intake of placenta capsules (3300 mg/d), a daily dose of placenta supplements contains approximately 0.018 ± 0.004 mg copper, 2.19 ± 0.533 mg iron, 0.005 ± 0.000 mg selenium, and 0.180 ± 0.018 mg zinc. Based on the recommended dietary allowance (RDA) for lactating women, the recommended daily intake of placenta capsules would provide, on average, 24% RDA for iron, 7.1% RDA for selenium, 1.5% RDA for zinc, and 1.4% RDA for copper. The mean concentrations of potentially harmful elements (arsenic, cadmium, lead, mercury, uranium) were well below established toxicity thresholds. These results indicate that the recommended daily intake of encapsulated placenta may provide only a modest source of some trace micronutrients and a minimal source of toxic elements. Copyright © 2016 Elsevier Inc. All rights reserved.

Chalcogenide Glass for Active and Passive Mid-IR Applications

DTIC Science & Technology

2010-09-01

Reactive gas conversion • Chemical vapour deposition What is a Chalcogenide? – From Greek sulphur-loving for elements that frequently bond to sulphur...Predominately As or Se based (toxic!) ORC Research Focussed On – Gallium Lanthanum Sulphides (non-toxic) – Germanium Sulphides (non-toxic) – Capability to...770 2 hours Primary Screening 2 - 3 days Time Scale: one week Pioneering Technology: High Throughput Physical Vapour Deposition Material Discovery

Blood levels of toxic metals and rare earth elements commonly found in e-waste may exert subtle effects on hemoglobin concentration in sub-Saharan immigrants.

PubMed

Henríquez-Hernández, Luis Alberto; Boada, Luis D; Carranza, Cristina; Pérez-Arellano, José Luis; González-Antuña, Ana; Camacho, María; Almeida-González, Maira; Zumbado, Manuel; Luzardo, Octavio P

2017-12-01

Pollution by heavy metals and more recently by rare earth elements (REE) and other minor elements (ME) has increased due in part to their high use in technological and electronic devices. This contamination can become very relevant in those sites where e-waste is improperly processed, as it is the case in many countries of the African continent. Exposure to some toxic elements has been associated to certain hematological disorders, specifically anemia. In this study, the concentrations of 48 elements (including REE and other ME) were determined by ICP-MS in whole blood samples of sub-Saharan immigrants with anemia (n=63) and without anemia (n=78). We found that the levels of Fe, Cr, Cu, Mn, Mo, and Se were significantly higher in the control group than in the anemia group, suggesting that anemia was mainly due to nutritional deficiencies. However, since other authors have suggested that in addition to nutritional deficiency, exposure to some elements may influence hemoglobin levels, we wanted to explore the role of a broad panel of toxic and "emerging" elements in hemoglobin deficiency. We found that the levels of Ag, As, Ba, Bi, Ce, Eu, Er, Ga, La, Nb, Nd, Pb, Pr, Sm, Sn, Ta, Th, Tl, U and V were higher in anemic participants than in controls. For most of these elements an inverse correlation with hemoglobin concentration was found. Some of them also correlated inversely with blood iron levels, pointing to the possibility that a higher rate of intestinal uptake of these could exist in relation to a nutritional deficiency of iron. However, the higher levels of Pb, and the group of REE and other ME in anemic participants were independent of iron levels, pointing to the possibility that these elements could play a role in the development of anemia. Copyright © 2017 Elsevier Ltd. All rights reserved.

Elements levels in dogs from "triangle of death" and different areas of Campania region (Italy).

PubMed

Zaccaroni, Annalisa; Corteggio, Annunziata; Altamura, Gennaro; Silvi, Marina; Di Vaia, Roberto; Formigaro, Costanza; Borzacchiello, Giuseppe

2014-08-01

In the last twenty years, many concerns have raised in Campania region (Southern Italy) about illegal waste dumping and toxic waste and their possible adverse effects on health. Many human activities are considered to be important sources of environmental pollutants, elements among them. In this study, pet dogs were enrolled as environmental sentinels from three different areas of Campania, with a different degree of pollution, evaluating elements in blood and hair. The obtained data indicated that dogs from less polluted area were exposed to a hot spot of pollution, as only animals from one city (Sessa Aurunca) presented elements concentrations very close to toxic levels. When excluding these animals, the area proved to be the less contaminated. The present report confirm the higher degree of pollution of the most industrialized areas, and a certain concern originates from Cr, Ni and As, which are present as levels well above toxic thresholds. These data are indicative of a reduced pollution of the areas considered by Cd and Pb, but arise concern for Hg, As, Cr and Ni, which reach concentrations high enough to impact dogs and humans health, in term of acute (in the city of Sessa Aurunca) and chronic toxicity (i.e. reproduction impairment, endocrine disruption, immunosuppression). Additional studies are necessary to better define not only the precise distribution of hot spots of pollution, but also the real impact of such an exposure on the health of dogs, in term of endocrine balance and/or immune system activity. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Installation Restoration Program Toxicology Guide. Volume 4

DTIC Science & Technology

1989-07-01

64.15 64-5 JP-4 Fuel-Water Partition Coefficients (K,) for Selected Hydrocarbons .......................... 64-20 04-6 Acute Toxicity of Components of JP...65.11 65-3 Equilibrium Partitioning of Select Gasoline Hydrocarbons in Model Environments ............... 65-14 65-4 Acute Toxicity of Components o...66-27 66-5 Acute Toxicity of Components of Fuel Oils ............ 66-37 67-1 Composition Dat,- for Stoddard Solvent

TCDD influences reservoir of antibiotic resistance genes in murine gut microbiome.

PubMed

Stedtfeld, Robert D; Stedtfeld, Tiffany M; Fader, Kelly A; Williams, Maggie R; Bhaduri, Prianca; Quensen, John; Zacharewski, Timothy R; Tiedje, James M; Hashsham, Syed A

2017-05-01

Dysbiosis of the gut microbiome via antibiotics, changes in diet and infection can select for bacterial groups that more frequently harbor antimicrobial resistance genes (ARGs) and mobile genetic elements (MGEs). However, the impact of environmental toxicants on the reservoir of ARGs in the gut microbiome has received less attention. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent aryl hydrocarbon receptor (AhR) agonist with multiple toxic health effects including immune dysfunction. The selective pressure of TCDD on the abundance of ARG and MGE-harboring gut populations was examined using C57BL/6 mice exposed to 0-30 μg/kg TCDD for 28 and 92 days with the latter having a 30-day recovery period. DNA extracted from temporally collected fecal pellets was characterized using a qPCR array with 384 assays targeting ARGs and MGEs. Fourteen genes, typically observed in Enterobacteriaceae, increased significantly within 8 days of initial dosing, persisted throughout the treatment period, and remained induced 30 days post dosing. A qPCR primer set targeting Enterobacteriaceae also showed 10- to 100-fold higher abundance in TCDD-treated groups, which was further verified using metagenomics. Results show a bloom of ARG-harboring bacterial groups in the gut due to a xenobiotic compound that is not a metal, biocide or antimicrobial. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Estimated Dietary Intakes of Toxic Elements from Four Staple Foods in Najran City, Saudi Arabia

PubMed Central

Haris, Parvez I.; Brima, Eid I.

2017-01-01

Exposure of the inhabitants of Najran area in Saudi Arabia to the toxic elements As, Cd, Cr, and Pb through foods has not been previously investigated. Exposure to such elements is an important public health issue, so the study described here was performed with the aim of determining estimated dietary intakes (EDIs) for these metals in Najran area. The As, Cd, Cr, and Pb concentrations in four staple foods (rice, wheat, red meat, and chicken) were determined by inductively coupled plasma-mass spectrometry. A food frequency questionnaire (FFQ) was completed by 80 study participants. These data were used to estimate dietary intakes of the metals in the four staple foods. The mean As, Cd, Cr, and Pb EDIs in the four food types were 1.1 × 10−6–2.6 × 10−5, 1.42 × 10−5–2.2 × 10−4, 3.4 × 10−4–8.0 × 10−4, and 2.3 × 10−5–2.1 × 10−3 mg/kg bw day, respectively. Hazard Quotients (HQ) for all elements did not exceed one. The highest Pb concentration was found for chicken and the source of this toxic element in this food needs to be investigated in the future. The lowest As concentration was found for wheat highest in rice. The EDIs for all elements in the four food types were below the provisional tolerable weekly intakes set by the World Health Organization (WHO). PMID:29240693

Metalloids, soil chemistry and the environment.

PubMed

Lombi, Enzo; Holm, Peter E

2010-01-01

This chapter reviews physical chemical properties, origin and use ofmetalloids and their relevance in the environment. The elements boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), polonium (Po) and astatine (At) are considered metalloids. Metalloids conduct heat and electricity intermediate between nonmetals and metals and they generally form oxides. The natural abundance ofmetalloids varies from Si being the second most common element in the Earth's crust to At as the rarest of natural elements on Earth. The metalloid elements Ge, Te, Po and At are normally present in trace or ultratrace levels in the environment and as such are not considered of relevance in terms of environmental health. The environmental geochemical processes, factors and parameters controlling the partitioning and the speciation of B, Si, As and Sb are reviewed in relation to the bioavailability of these metalloids. Approaches based on the hypothesis that metal toxicity is related to both the metal-ligand complexation processes and the metal interactions with competing cations at the cell surface (biotic ligand) have so far not been successful for assessing metalloid bioavailability. The chapter concludes that our understanding of metalloids toxicity will improve in the future if, in addition to the points discussed above, surface membrane potentials are considered. This should represent a robust approach to the prediction of metalloid toxicity.

Prompt gamma neutron activation analysis of toxic elements in radioactive waste packages.

PubMed

Ma, J-L; Carasco, C; Perot, B; Mauerhofer, E; Kettler, J; Havenith, A

2012-07-01

The French Alternative Energies and Atomic Energy Commission (CEA) and National Radioactive Waste Management Agency (ANDRA) are conducting an R&D program to improve the characterization of long-lived and medium activity (LL-MA) radioactive waste packages. In particular, the amount of toxic elements present in radioactive waste packages must be assessed before they can be accepted in repository facilities in order to avoid pollution of underground water reserves. To this aim, the Nuclear Measurement Laboratory of CEA-Cadarache has started to study the performances of Prompt Gamma Neutron Activation Analysis (PGNAA) for elements showing large capture cross sections such as mercury, cadmium, boron, and chromium. This paper reports a comparison between Monte Carlo calculations performed with the MCNPX computer code using the ENDF/B-VII.0 library and experimental gamma rays measured in the REGAIN PGNAA cell with small samples of nickel, lead, cadmium, arsenic, antimony, chromium, magnesium, zinc, boron, and lithium to verify the validity of a numerical model and gamma-ray production data. The measurement of a ∼20kg test sample of concrete containing toxic elements has also been performed, in collaboration with Forschungszentrum Jülich, to validate the model in view of future performance studies for dense and large LL-MA waste packages. Copyright © 2012 Elsevier Ltd. All rights reserved.

Rare earth elements in human and animal health: State of art and research priorities.

PubMed

Pagano, Giovanni; Aliberti, Francesco; Guida, Marco; Oral, Rahime; Siciliano, Antonietta; Trifuoggi, Marco; Tommasi, Franca

2015-10-01

A number of applications have been developed using rare earth elements (REE), implying several human exposures and raising unsolved questions as to REE-associated health effects. A MedLine survey was retrieved from early reports (1980s) up to June 2015, focused on human and animal exposures to REE. Literature from animal models was selected focusing on REE-associated health effects. Some REE occupational exposures, in jobs such as glass polishers, photoengravers and movie projectionists showed a few case reports on health effects affecting the respiratory system. No case-control or cohort studies of occupational REE exposures were retrieved. Environmental exposures have been biomonitored in populations residing in REE mining areas, showing REE accumulation. The case for a iatrogenic REE exposure was raised by the use of gadolinium-based contrast agents for nuclear magnetic resonance. Animal toxicity studies have shown REE toxicity, affecting a number of endpoints in liver, lungs and blood. On the other hand, the use of REE as feed additives in livestock is referred as a safe and promising device in zootechnical activities, possibly suggesting a hormetic effect both known for REE and for other xenobiotics. Thus, investigations on long-term exposures and observations are warranted. The state of art provides a limited definition of the health effects in occupationally or environmentally REE-exposed human populations. Research priorities should be addressed to case-control or cohort studies of REE-exposed humans and to life-long animal experiments. Copyright © 2015 Elsevier Inc. All rights reserved.

AUTOMATED RESPIROMETER METHOD FOR MICROBIAL TOXICITY ASSESSMENT OF LOW-LEVEL ZINC CONTAMINATION IN SOIL

EPA Science Inventory

Zinc is an essential trace element for all living organisms including humans. ecause microbial-based toxicity approaches to assess the changes in ecosystem processes are not well defined for soil application, this laboratory has developed an automated respirometer capable of meas...

COMPARING THE RECOMMENDED DIETARY ALLOWANCE TO TOXICITY VALUES FOR ZN, SE, MN, AND MB

EPA Science Inventory

Certain essential nutrients can be toxic when ingested at dosages higher than the daily nutritional requirement. Research data for the essential trace elements, zinc, selenium, manganese and molybdenum have been reviewed by various government agencies for both their nutritional n...

Elemental Characterization of Hardpan Topping Selected Sections of Ajali Sand, Anambra Basin. Nigeria.

NASA Astrophysics Data System (ADS)

Ajidahun, E. J.

2015-12-01

The hardpan cap of selected sections of loose Ajali sand in Anambra Basin of Nigeria was investigated for elemental compositions using Energy Dispersive X-Ray Fluorescence mapping (M4-Tornado ED-XRF); while bulk mineralogy was determined by X-Ray Diffraction and Scanning Electron Microscopy (SEM) at the Federal Institute for Geosciences and Natural Resources (BGR), Hannover, Germany. Elemental maps of Fe, Si, Ti, Al, Cr etc. were used to highlight texture and mineral distribution. The Ajali sands are locally topped by iron rich hardpans. These hardpans consist of rock fragments up to several cm in length in a primary matrix and locally large pores. Besides laminated sandstone fragments, highly altered porphyritic volcanic rocks can be observed. The latter in the SEM appear highly spongeous, and show relics of phenochryts such as biotite, hornblende and pyroxene, corroded magmatic quartz, magnetite, Ilmenite, zircon or voids of former crystals in an almost entirely altered matrix Large pores show several generations of periodic infill of quartz sand / soil mixtures alternating with multiple layers of Fe rich precipitates, locally enriched in Al, P, S, Mn or Sr agglutinating the fines. Volcanic fragments show rims of elevated Cr content, and Cr and V-rich precipitates may separate generations of infill. A number of large open pore channels rimmed by Fe-rich matrix might act as water channels. They are coated by Al, K rich precipitates. Ajali sands can hardly be considered as the source for the agglutination of the hardpan cap. The source of Fe and other elements such as Al, K, Cr, V has to be attributed to the volcanic fragments, mainly to the matrix, but to the altered phenocrysts, too. Toxic elements such as Cr being mobile in the system are in part stabilized as precipitates. EDXRF-micro mapping provides excellent textural, chemical and even mineralogical information to get better insight into the sedimentation and agglutination history of the hardpan cap. Key words: Hardpan Cap, Ajali Sands, Anambra Basin, Agglutination, Volcanic Fragment.

Temporal variations of low molecular mass organic acids during vegetation period in temperate forest soil affected by acidification

NASA Astrophysics Data System (ADS)

Tejnecky, V.; Drabek, O.; Bradová, M.; Němeček, K.; Šebek, O.; Zenáhlíková, J.; Boruvka, L.

2011-12-01

The Low Molecular Mass Organic Acids (LMMOA) are essential in processes affecting the soils and represent reactive fraction of dissolved organic carbon (DOC). LMMOA influence soil-chemistry behaviour, participate in transport of mineral nutrition and reduce potential toxicity of selected elements like Al. The aim of this research was to assess behaviour, amount and composition of LMMOA in forest soil under different vegetation cover. The researched area is located in the naturally acid Jizera Mountains (Czech Republic), which was further affected by acid deposition and improper forest management. Soil samples from organic F and H horizons, organo-mineral A horizon and spodic or cambic mineral B horizons were taken under beech and spruce stands monthly (from April to October). Both stands were located immediately next to each other. The collected soil samples were analyzed immediately in a "fresh" state. Contents of LMMOA in deionised water extract were determined by means of ion-exchange chromatography (ICS-1600, Dionex, USA) with suppressed conductivity and gradient elution of KOH mobile phase. The contents of LMMOAS were also determined in precipitation samples. In addition, other selected elements (Al, Fe, Ca, Na, Mg and K), Al speciation and main inorganic anions were determined in water extract and precipitation samples. The highest amounts of LMMOA (mainly lactic, acetic, formic, malic and oxalic acid) were observed in organic F and H horizons and measured amounts decreased with increasing soil profile depth. Higher contents were determined in soil under spruce forest than under beech forest. External inputs of LMMOA in a form of precipitation were assessed as less significant in comparison with the soil processes (e.g. soil biological activity, soil organic matter decomposition processes). LMMOA amounts were higher in spring and summer (from April to August), caused by increased biological activity, while lower amounts were observed during the autumn period. Soil LMMOA were influencing also Al behaviour and Al species representation to less potentially toxic Al species.

Potentially toxic elements and environmentally-related pollutants recognition using colorimetric and ratiometric fluorescent probes.

PubMed

Rasheed, Tahir; Li, Chuanlong; Bilal, Muhammad; Yu, Chunyang; Iqbal, Hafiz M N

2018-05-30

A safer detection or sensing of toxic pollutants is one among several environmental contamination issues, across the globe. The ever-increasing industrial practices and controlled or uncontrolled release of toxic pollutants from various industrial sectors is a key source of this environmental problem. Significant research efforts have been or being made to tackle this problematic issue to fulfill the growing needs of the modern world. Despite many useful aspects, heavy metals are posing noteworthy toxicological concerns and human-health related issues at various levels of the ecosystem. In this context, notable efforts from various regulatory authorities, the increase in the concentration of these toxic heavy metals in the environment is of serious concern, so real-time monitoring is urgently required. Herein, we reviewed fluorescent sensor based models and their potentialities to address the detection fate of hazardous pollutants including chromium, manganese, cobalt, nickel, copper, and zinc as model elements. The novel aspects of turn-on/off fluorescent sensors have also been discussed from a state of the art viewpoint. In summary, comprehensive literature regarding fluorescent sensor based models and their potentialities to detect various types of toxic pollutants is reviewed. Copyright © 2018 Elsevier B.V. All rights reserved.

Identifying the causes of oil sands coke leachate toxicity to aquatic invertebrates.

PubMed

Puttaswamy, Naveen; Liber, Karsten

2011-11-01

A previous study found that coke leachates (CL) collected from oil sands field sites were acutely toxic to Ceriodaphnia dubia; however, the cause of toxicity was not known. Therefore, the purpose of this study was to generate CL in the laboratory to evaluate the toxicity response of C. dubia and perform chronic toxicity identification evaluation (TIE) tests to identify the causes of CL toxicity. Coke was subjected to a 15-d batch leaching process at pH 5.5 and 9.5. Leachates were filtered on day 15 and used for chemical and toxicological characterization. The 7-d median lethal concentration (LC50) was 6.3 and 28.7% (v/v) for pH 5.5 and 9.5 CLs, respectively. Trace element characterization of the CLs showed Ni and V levels to be well above their respective 7-d LC50s for C. dubia. Addition of ethylenediaminetetraacetic acid significantly (p ≤ 0.05) improved survival and reproduction in pH 5.5 CL, but not in pH 9.5 CL. Cationic and anionic resins removed toxicity of pH 5.5 CL only. Conversely, the toxicity of pH 9.5 CL was completely removed with an anion resin alone, suggesting that the pH 9.5 CL contained metals that formed oxyanions. Toxicity reappeared when Ni and V were added back to anion resin-treated CLs. The TIE results combined with the trace element chemistry suggest that both Ni and V are the cause of toxicity in pH 5.5 CL, whereas V appears to be the primary cause of toxicity in pH 9.5 CL. Environmental monitoring and risk assessments should therefore focus on the fate and toxicity of metals, especially Ni and V, in coke-amended oil sands reclamation landscapes. Copyright © 2011 SETAC.

The influence of salinity on the toxicity of selected sulfonamides and trimethoprim towards the green algae Chlorella vulgaris.

PubMed

Borecka, Marta; Białk-Bielińska, Anna; Haliński, Łukasz P; Pazdro, Ksenia; Stepnowski, Piotr; Stolte, Stefan

2016-05-05

This paper presents the investigation of the influence of salinity variations on the toxicity of sulfapyridine, sulfamethoxazole, sulfadimethoxine and trimethoprim towards the green algae Chlorella vulgaris after exposure times of 48 and 72 h. In freshwater the EC50 values ranged from 0.98 to 123.22 mg L(-1) depending on the compound. The obtained results revealed that sulfamethoxazole and sulfapyridine were the most toxic, while trimethoprim was the least toxic pharmaceutical to the selected organism. Deviations between the nominal and real test concentrations were determined via instrumental analysis to support the interpretation of ecotoxicological data. The toxicity effects were also tested in saline water (3, 6 and 9 PSU). The tendency that the toxicity of selected pharmaceuticals decreases with increasing salinity was observed. Higher salinity implies an elevated concentration of inorganic monovalent cations that are capable of binding with countercharges available on algal surfaces (hydroxyl functional groups). Hence it can reduce the permeability of pharmaceuticals through the algal cell walls, which could be the probable reason for the observed effect. Moreover, for the classification of the mode of toxic action, the toxic ratio concept was applied, which indicated that the effects of the investigated drugs towards algae are caused by the specific mode of toxic action. Copyright © 2016 Elsevier B.V. All rights reserved.

A Novel Inhibitor Of Topoisomerase I is Selectively Toxic For A Subset of Non-Small Cell Lung Cancer Cell Lines | Office of Cancer Genomics

Cancer.gov

SW044248, identified through a screen for chemicals that are selectively toxic for NSCLC cell lines, was found to rapidly inhibit macromolecular synthesis in sensitive, but not in insensitive cells. SW044248 killed approximately 15% of a panel of 74 NSCLC cell lines and was non-toxic to immortalized human bronchial cell lines.

Patterns and trends in sediment toxicity in the San Francisco Estuary

USGS Publications Warehouse

Anderson, B.; Hunt, J.; Phillips, B.; Thompson, B.; Lowe, S.; Taberski, K.; Scott, Carr R.

2007-01-01

Widespread sediment toxicity has been documented throughout the San Francisco Estuary since the mid-1980s. Studies conducted in the early 1990s as part of the Bay Protection and Toxic Cleanup Program (BPTCP), and more recently as part of the Regional Monitoring Program (RMP) have continued to find sediment toxicity in the Estuary. Results of these studies have shown a number of sediment toxic hotspots located at selected sites in the margins of the Estuary. Recent RMP monitoring has indicated that the magnitude and frequency of sediment toxicity is greater in the winter wet season than in the summer dry season, which suggests stormwater inputs are associated with sediment toxicity. Additionally, spatial trends in sediment toxicity data indicate that toxic sediments are associated with inputs from urban creeks surrounding the Estuary, and from Central Valley rivers entering the northern Estuary via the Delta. Sediment toxicity has been correlated with a number of contaminants, including selected metals, PAHs and organochlorine pesticides. While toxicity identification evaluations (TIEs) suggest that metals are the primary cause of sediment toxicity to bivalve embryos; TIEs conducted with amphipods have been inconclusive. ?? 2006 Elsevier Inc. All rights reserved.

Predicting Water Quality Problems Associated with Coal Fly Ash Disposal Facilities Using a Trace Element Partitioning Study

NASA Astrophysics Data System (ADS)

Bhattacharyya, S.; Donahoe, R. J.; Graham, E. Y.

2006-12-01

For much of the U.S., coal-fired power plants are the most important source of electricity for domestic and industrial use. Large quantities of fly ash and other coal combustion by-products are produced every year, the majority of which is impounded in lagoons and landfills located throughout the country. Many older fly ash disposal facilities are unlined and have been closed for decades. Fly ash often contains high concentrations of toxic trace elements such as arsenic, boron, chromium, molybdenum, nickel, selenium, lead, strontium and vanadium. Trace elements present in coal fly ash are of potential concern due to their toxicity, high mobility in the environment and low drinking water MCL values. Concern about the potential release of these toxic elements into the environment due to leaching of fly ash by acid rain, groundwater or acid mine drainage has prompted the EPA to develop national standards under the subtitle D of the Resource Conservation and Recovery Act (RCRA) to regulate ash disposal in landfills and surface impoundments. An attempt is made to predict the leaching of toxic elements into the environment by studying trace element partitioning in coal fly ash. A seven step sequential chemical extraction procedure (SCEP) modified from Filgueiras et al. (2002) is used to determine the trace element partitioning in seven coal fly ash samples collected directly from electric power plants. Five fly ash samples were derived from Eastern Bituminous coal, one derived from Western Sub-bituminous coal and the other derived from Northern Lignite. The sequential chemical extraction procedure gives valuable information on the association of trace elements: 1) soluble fraction, 2) exchangeable fraction, 3) acid soluble fraction, 4) easily reducible fraction, 5) moderately reducible fraction, 6) poorly reducible fraction and 7) oxidizable organics/sulfide fraction. The trace element partitioning varies with the composition of coal fly ash which is influenced by the type of coal burned. Preliminary studies show that in some fly ash samples, significant amounts of As, B, Mo, Se, Sr and V are associated with the soluble and exchangeable fraction, and thus would be highly mobile in the environment. Lead, on the other hand, is mainly associated with the amorphous Fe and Mn oxide fractions and would be highly immobile in oxidizing conditions, but mobile in reducing conditions. Ni and Cr show different associations in different fly ash samples. In most fly ash samples, significant amounts of the trace elements are associated with more stable fractions that do not threaten the environment. The study of trace element partitioning in coal fly ash thus helps us to predict their leaching behavior under various conditions.

Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops*

PubMed Central

Islam, Ejaz ul; Yang, Xiao-e; He, Zhen-li; Mahmood, Qaisar

2007-01-01

Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary toxicity. PMID:17173356

Assessing potential dietary toxicity of heavy metals in selected vegetables and food crops.

PubMed

Islam, Ejaz ul; Yang, Xiao-e; He, Zhen-li; Mahmood, Qaisar

2007-01-01

Heavy metals, such as cadmium, copper, lead, chromium and mercury, are important environmental pollutants, particularly in areas with high anthropogenic pressure. Their presence in the atmosphere, soil and water, even in traces can cause serious problems to all organisms, and heavy metal bioaccumulation in the food chain especially can be highly dangerous to human health. Heavy metals enter the human body mainly through two routes namely: inhalation and ingestion, ingestion being the main route of exposure to these elements in human population. Heavy metals intake by human populations through food chain has been reported in many countries. Soil threshold for heavy metal toxicity is an important factor affecting soil environmental capacity of heavy metal and determines heavy metal cumulative loading limits. For soil-plant system, heavy metal toxicity threshold is the highest permissible content in the soil (total or bioavailable concentration) that does not pose any phytotoxic effects or heavy metals in the edible parts of the crops does not exceed food hygiene standards. Factors affecting the thresholds of dietary toxicity of heavy metal in soil-crop system include: soil type which includes soil pH, organic matter content, clay mineral and other soil chemical and biochemical properties; and crop species or cultivars regulated by genetic basis for heavy metal transport and accumulation in plants. In addition, the interactions of soil-plant root-microbes play important roles in regulating heavy metal movement from soil to the edible parts of crops. Agronomic practices such as fertilizer and water managements as well as crop rotation system can affect bioavailability and crop accumulation of heavy metals, thus influencing the thresholds for assessing dietary toxicity of heavy metals in the food chain. This paper reviews the phytotoxic effects and bioaccumulation of heavy metals in vegetables and food crops and assesses soil heavy metal thresholds for potential dietary toxicity.

Illumina microRNA profiles reveal the involvement of miR397a in Citrus adaptation to long-term boron toxicity via modulating secondary cell-wall biosynthesis.

PubMed

Huang, Jing-Hao; Qi, Yi-Ping; Wen, Shou-Xing; Guo, Peng; Chen, Xiao-Min; Chen, Li-Song

2016-03-10

The mechanisms underlying tolerance to B-toxicity in plants are still controversial. Our previous studies indicated that B-toxicity is mainly limited to leaves in Citrus and that alternations of cell-wall structure in vascular bundles are involved in tolerance to B-toxicity. Here, miRNAs and their expression patterns were first identified in B-treated Citrus sinensis (tolerant) and C. grandis (intolerant) leaves via high-throughput sequencing. Candidate miRNAs were then verified with molecular and anatomical approaches. The results showed that 51 miRNAs in C. grandis and 20 miRNAs in C. sinensis were differentially expressed after B-toxic treatment. MiR395a and miR397a were the most significantly up-regulated miRNAs in B-toxic C. grandis leaves, but both were down-regulated in B-toxic C. sinensis leaves. Four auxin response factor genes and two laccase (LAC) genes were confirmed through 5'-RACE to be real targets of miR160a and miR397a, respectively. Up-regulation of LAC4 resulted in secondary deposition of cell-wall polysaccharides in vessel elements of C. sinensis, whereas down-regulation of both LAC17 and LAC4, led to poorly developed vessel elements in C. grandis. Our findings demonstrated that miR397a plays a pivotal role in woody Citrus tolerance to B-toxicity by targeting LAC17 and LAC4, both of which are responsible for secondary cell-wall synthesis.

Toxic effects of environmental rare earth elements on delayed outward potassium channels and their mechanisms from a microscopic perspective.

PubMed

Wang, Lihong; He, Jingfang; Xia, Ao; Cheng, Mengzhu; Yang, Qing; Du, Chunlei; Wei, Haiyan; Huang, Xiaohua; Zhou, Qing

2017-08-01

The wide applications cause a large amount of rare earth elements (REEs) to be released into the environment, and ultimately into the human body through food chain. Toxic effects of REEs on humans have been extensively studied, but their toxic effects and binding targets in cells are not understood. Delayed outward potassium channels (K + channels) are good targets for exogenous substances or clinical drugs. To evaluate cellular toxicities of REEs and clarify toxic mechanisms, the toxicities of REEs on the K + channel and their structural basis were investigated. The results showed that delayed outward potassium channels on the plasma membrane are the targets of REEs acting on living organisms, and the changes in the thermodynamic and kinetic characteristics of the K + channel are the reasons of diseases induced by REEs. Two types of REEs, a light REE La 3+ and a heavy REE Tb 3+ , displayed different intensity of toxicities on the K + channel, in which the toxicity of Tb 3+ was stronger than that of La 3+ . More interestingly, in comparison with that of heavy metal Cd 2+ , the cytotoxicities of the light and heavy REEs showed discriminative differences, and the cytotoxicity of Tb 3+ was higher than that of Cd 2+ , while the cytotoxicity of La 3+ was lower than that of Cd 2+ . These different cytotoxicities of La 3+ , Tb 3+ and Cd 2+ on human resulted from the varying binding abilities of the metals to this channel protein. Copyright © 2017 Elsevier Ltd. All rights reserved.

Illumina microRNA profiles reveal the involvement of miR397a in Citrus adaptation to long-term boron toxicity via modulating secondary cell-wall biosynthesis

PubMed Central

Huang, Jing-Hao; Qi, Yi-Ping; Wen, Shou-Xing; Guo, Peng; Chen, Xiao-Min; Chen, Li-Song

2016-01-01

The mechanisms underlying tolerance to B-toxicity in plants are still controversial. Our previous studies indicated that B-toxicity is mainly limited to leaves in Citrus and that alternations of cell-wall structure in vascular bundles are involved in tolerance to B-toxicity. Here, miRNAs and their expression patterns were first identified in B-treated Citrus sinensis (tolerant) and C. grandis (intolerant) leaves via high-throughput sequencing. Candidate miRNAs were then verified with molecular and anatomical approaches. The results showed that 51 miRNAs in C. grandis and 20 miRNAs in C. sinensis were differentially expressed after B-toxic treatment. MiR395a and miR397a were the most significantly up-regulated miRNAs in B-toxic C. grandis leaves, but both were down-regulated in B-toxic C. sinensis leaves. Four auxin response factor genes and two laccase (LAC) genes were confirmed through 5′-RACE to be real targets of miR160a and miR397a, respectively. Up-regulation of LAC4 resulted in secondary deposition of cell-wall polysaccharides in vessel elements of C. sinensis, whereas down-regulation of both LAC17 and LAC4, led to poorly developed vessel elements in C. grandis. Our findings demonstrated that miR397a plays a pivotal role in woody Citrus tolerance to B-toxicity by targeting LAC17 and LAC4, both of which are responsible for secondary cell-wall synthesis. PMID:26962011

A Review of Events That Expose Children to Elemental Mercury in the United States

PubMed Central

Lee, Robin; Middleton, Dan; Caldwell, Kathleen; Dearwent, Steve; Jones, Steven; Lewis, Brian; Monteilh, Carolyn; Mortensen, Mary Ellen; Nickle, Richard; Orloff, Kenneth; Reger, Meghan; Risher, John; Rogers, Helen Schurz; Watters, Michelle

2009-01-01

Objective Concern for children exposed to elemental mercury prompted the Agency for Toxic Substances and Disease Registry and the Centers for Disease Control and Prevention to review the sources of elemental mercury exposures in children, describe the location and proportion of children affected, and make recommendations on how to prevent these exposures. In this review, we excluded mercury exposures from coal-burning facilities, dental amalgams, fish consumption, medical waste incinerators, or thimerosal-containing vaccines. Data sources We reviewed federal, state, and regional programs with information on mercury releases along with published reports of children exposed to elemental mercury in the United States. We selected all mercury-related events that were documented to expose (or potentially expose) children. We then explored event characteristics (i.e., the exposure source, location). Data synthesis Primary exposure locations were at home, at school, and at other locations such as industrial property not adequately remediated or medical facilities. Exposure to small spills from broken thermometers was the most common scenario; however, reports of such exposures are declining. Discussion and conclusions Childhood exposures to elemental mercury often result from inappropriate handling or cleanup of spilled mercury. The information reviewed suggests that most releases do not lead to demonstrable harm if the exposure period is short and the mercury is properly cleaned up. Recommendations Primary prevention should include health education and policy initiatives. For larger spills, better coordination among existing surveillance systems would assist in understanding the risk factors and in developing effective prevention efforts. PMID:19590676

Low doses of six toxicants change plant size distribution in dense populations of Lactuca sativa.

PubMed

Belz, Regina G; Patama, Marjo; Sinkkonen, Aki

2018-08-01

Toxicants are known to have negligible or stimulatory, i.e. hormetic, effects at low doses below those that decrease the mean response of a plant population. Our earlier observations indicated that at such low toxicant doses the growth of very fast- and slow-growing seedlings is selectively altered, even if the population mean remains constant. Currently, it is not known how common these selective low-dose effects are, whether they are similar among fast- and slow-growing seedlings, and whether they occur concurrently with hormetic effects. We tested the response of Lactuca sativa in complete dose-response experiments to six different toxicants at doses that did not decrease population mean and beyond. The tested toxicants were IAA, parthenin, HHCB, 4-tert-octylphenol, glyphosate, and pelargonic acid. Each experiment consisted of 14,400-16,800 seedlings, 12-14 concentrations, 24 replicates per concentration and 50 germinated seeds per replicate. We analyzed the commonness of selective low-dose effects and explored if toxic effects and hormetic stimulation among fast- and slow-growing individuals occurred at the same concentrations as they occur at the population level. Irrespective of the observed response pattern and toxicant, selective low-dose effects were found. Toxin effects among fast-growing individuals usually started at higher doses compared to the population mean, while the opposite was found among slow-growing individuals. Very low toxin exposures tended to homogenize plant populations due to selective effects, while higher, but still hormetic doses tended to heterogenize plant populations. Although the extent of observed size segregation varied with the specific toxin tested, we conclude that a dose-dependent alteration in size distribution of a plant population may generally apply for many toxin exposures. Copyright © 2018 Elsevier B.V. All rights reserved.

Levels of selected metals in ambient air PM10 in an urban site of Zaragoza (Spain).

PubMed

López, J M; Callén, M S; Murillo, R; García, T; Navarro, M V; de la Cruz, M T; Mastral, A M

2005-09-01

An assessment of the air quality of Zaragoza (Spain) was performed by determining the trace element content in airborne PM10 in a sampling campaign from July 2001 to July 2002. Samples were collected in a heavy traffic area with a high volume air sampler provided with a PM10 cutoff inlet. The levels of 16 elements (Al, Ba, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, V, and Zn) were quantified after collecting the PM10 on Teflon-coated glass fiber filters (GFF). Regarding the PM10, 32% exceedance of the proposed PM10 daily limit was obtained, some of them corresponding to summer and autumn periods. The limit values of toxic trace elements from US-EPA, WHO, and EC were not exceeded, considering Zaragoza as a moderately polluted city under the current air quality guidelines. The contribution of anthropogenic sources to atmospheric elemental levels was reflected by the high values of enrichment factors for Zn, Pb, and Cu compared to the average crustal composition. Statistical analyses also determined the contribution of different sources to the PM10, finding that vehicle traffic and anthropogenic emissions related to combustion and industrial processes were the main pollutant sources as well as natural sources associated with transport of dust from Africa for specific dates. Regarding the influence of meteorological conditions on PM10 and trace elements concentrations, it was found that calm weather conditions with low wind speed favor the PM10 collection and the pollution for trace elements, suggesting the influence of local sources.

Pesticide mobility and leachate toxicity in two abandoned mine soils. Effect of organic amendments.

PubMed

Rodríguez-Liébana, José Antonio; Mingorance, M Dolores; Peña, Aránzazu

2014-11-01

Abandoned mine areas, used in the past for the extraction of minerals, constitute a degraded landscape which needs to be reintegrated to productive or leisure activities. However these soils, mainly composed by silt or sand and with low organic matter content, are vulnerable to organic and inorganic pollutants posing a risk to the surrounding ecosystems and groundwater. Soils from two mining areas from Andalusia were evaluated: one from Nerva (NCL) in the Iberian Pyrite Belt (SW Andalusia) and another one from the iron Alquife mine (ALQ) (SE Andalusia). To improve soil properties and fertility two amendments, stabilised sewage sludge (SSL) and composted sewage sludge (CSL), were selected. The effect of amendment addition on the mobility of two model pesticides, thiacloprid and fenarimol, was assessed using soil columns under non-equilibrium conditions. Fenarimol, more hydrophobic than thiacloprid, only leached from native ALQ, a soil with lower organic carbon (OC) content than NCL (0.21 and 1.4%, respectively). Addition of amendments affected differently pesticide mobility: thiacloprid in the leachates was reduced by 14% in NCL-SSL and by 4% in ALQ-CSL. Soil OC and dissolved OC were the parameters which explained pesticide residues in soil. Chemical analysis revealed that leachates from the different soil columns did not contain toxic element levels, except As in NCL soil. Finally ecotoxicological data showed moderate toxicity in the initial leachates, with an increase coinciding with pesticide maximum concentration. The addition of SSL slightly reduced the toxicity towards Vibrio fischeri, likely due to enhanced retention of pesticides by amended soils. Copyright © 2014 Elsevier B.V. All rights reserved.

Biogeochemical processes underpin ecosystem services

USDA-ARS?s Scientific Manuscript database

Elemental cycling is critical to the function of ecosystems and delivery of key ecosystem services because many of these elements are essential nutrients or detrimental toxicants that directly affect the health of organisms and ecosystems. A team of authors from North Carolina State University and ...

Environmental exposures of trace elements assessed using keratinized matrices from patients with chronic kidney diseases of uncertain etiology (CKDu) in Sri Lanka.

PubMed

Diyabalanage, Saranga; Fonseka, Sanjeewani; Dasanayake, D M S N B; Chandrajith, Rohana

2017-01-01

An alarming increase in chronic kidney disease with unknown etiology (CKDu) has recently been reported in several provinces in Sri Lanka and chronic exposures to toxic trace elements were blamed for the etiology of this disease. Keratinized matrices such as hair and nails were investigated to determine the possible link between CKDu and toxic element exposures. Elements Li, B, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Cd, Ba, Hg and Pb of hair and nails of patients and age that matched healthy controls were determined with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results showed that trace element contents in the hair of patients varies in the order of Zn>Fe>Al>Mn>Cu>Ba>Sr>Ni>Pb>Cr>B>Hg>Se>Mo>Co>As>Li>Cd while Fe>Al>Zn>Ni>Cu>Mn>Cr>Ba>Sr>B>Pb>Se>Mo>Co>Hg>Li>As>Cd in nail samples. The hair As levels of 0.007-0.165μgg -1 were found in CKDu subjects. However, no significant difference was observed between cases and controls. The total Se content in hair of CKDu subjects ranged from 0.043 to 0.513μgg -1 while it was varied from 0.031 to 1.15μgg -1 in controls. Selenium in nail samples varied from 0.037μgg -1 to 4.10μgg -1 in CKDu subjects and from 0.042μgg -1 to 2.19μgg -1 in controls. This study implies that substantial proportions of Sri Lankan population are Se deficient irrespective of gender, age and occupational exposure. Although some cutaneous manifestations were observed in patient subjects, chemical analyses of hair and nails indicated that patients were not exposed to toxic levels of arsenic or the other studied toxic elements. Therefore the early suggested causative factors such as exposure to environmental As and Cd, can be ruled out. Copyright © 2016 Elsevier GmbH. All rights reserved.

Contamination of organic nutrient sources with potentially toxic elements, antibiotics and pathogen microorganisms in relation to P fertilizer potential and treatment options for the production of sustainable fertilizers: A review.

PubMed

Bloem, E; Albihn, A; Elving, J; Hermann, L; Lehmann, L; Sarvi, M; Schaaf, T; Schick, J; Turtola, E; Ylivainio, K

2017-12-31

Organic nutrient sources such as farmyard manure, sewage sludge, their biogas digestates or other animal by-products can be valuable fertilizers delivering organic matter to the soil. Currently, especially phosphorus (P) is in the focus of research since it is an essential plant nutrient with finite resources, estimated to last only for some more decades. Efficient utilization of organic P sources in agriculture will help to preserve P resources and thereby has the potential to close nutrient cycles and prevent unwanted P-losses to the environment, one of the major causes for eutrophication of water bodies. Unfortunately, organic P sources usually contain also various detrimental substances, such as potentially toxic elements or organic contaminants like pharmaceuticals as well as pathogenic microorganisms. Additionally, the utilization of some of these substrates such as sewage sludge or animal by-products is legally limited in agriculture because of the potential risk to contaminate sites with potentially toxic elements and organic contaminants. Thus, to close nutrient cycles it is important to develop solutions for the responsible use of organic nutrient sources. The aim of this review is to give an overview of the contamination of the most important organic nutrient sources with potentially toxic elements, antibiotics (as one important organic contaminant) and pathogenic microorganisms. Changes in manure and sewage sludge management as well as the increasing trend to use such substrates in biogas plants will be discussed with respect to potential risks posed to soils and water bodies. Some examples for abatement options by which contamination can be reduced to produce P fertilizers with high amounts of plant available P forms are presented. Copyright © 2017 Elsevier B.V. All rights reserved.

Monitoring impacts of air pollution: PIXE analysis and histopathological modalities in evaluating relative risks of elemental contamination.

PubMed

Ejaz, Sohail; Camer, Gerry Amor; Anwar, Khaleeq; Ashraf, Muhammad

2014-04-01

Environmental toxicants invariably affect all biological organisms resulting to sufferings ranging from subclinical to debilitating clinical conditions. This novel research aimed to determine the toxic burdens of increased environmental elements in some vital organs/tissues of the wild animals (starling, owl, crow and pigeon), exposed to air polluted environment were assessed using particle induced X-ray emission and histopathological approaches. The presence of significantly elevated amounts of elemental toxicants namely: Aluminum (Al), Chlorine (Cl), Iron (Fe), Potassium (K), Magnesium (Mg), Manganese (Mn), Silicon (Si) and Vanadium (V) from the skin, muscle, lungs, liver and kidney of sampled animals were in concurrence with the observed histopathological changes. The skin of sampled starling, owl, pigeon and crow spotlighted highly significant increase (P < 0.001) in Al, Cl, Mg and Si. Muscle samples with myodegenerative lesions and mineral depositions highlighted substantial augmentation (P < 0.001) in the amount of Al, Fe, Mn, Si and V. The lungs of starling, owl, and pigeon were severely intoxicated (P < 0.001) with increased amount of Al, Fe, K, Mn and Si producing pulmonary lesions of congestion, edema, pneumonitis and mineral debris depositions. Liver samples revealed that the sampled animals were laden with Cl, Fe, Mg, Mn and V with histopathological profound degenerative changes and hepatic necrosis. Kidney sections presented severe tubular degenerative and necrotic changes that may be attributed to increased amounts of Cl and Fe. These current findings implied that the environmental/elemental toxicants and the accompanying lesions that were discerned in the organs/tissues of sampled birds may as well be afflicting people living within the polluted area. Further assessment to more conclusively demonstrate correlations of current findings to those of the populace within the area is encouraged.

Use of neutralized industrial residue to stabilize trace elements (Cu, Cd, Zn, As, Mo, and Cr) in marine dredged sediment from South-East of France.

PubMed

Taneez, Mehwish; Marmier, Nicolas; Hurel, Charlotte

2016-05-01

Management of marine dredged sediments polluted with trace elements is prime issue in the French Mediterranean coast. The polluted sediments possess ecological threats to surrounding environment on land disposal. Therefore, stabilization of contaminants in multi-contaminated marine dredged sediment is a promising technique. Present study aimed to assess the effect of gypsum neutralized bauxaline(®) (bauxite residue) to decrease the availability of pollutants and inherent toxicity of marine dredged sediment. Bauxaline(®), (alumia industry waste) contains high content of iron oxide but its high alkalinity makes it not suitable for the stabilization of all trace elements from multi-contaminated dredged sediments. In this study, neutralized bauxaline(®) was prepared by mixing bauxaline(®) with 5% of plaster. Experiments were carried out for 3 months to study the effect of 5% and 20% amendment rate on the availability of Cu, Cd, Zn, As, Mo, and Cr. Trace elements concentration, pH, EC and dissolved organic carbon were measured in all leachates. Toxicity of leachates was assessed against marine rotifers Brachionus plicatilis. The Results showed that both treatments have immobilization capacity against different pollutants. Significant stabilization of contaminants (Cu, Cd, Zn) was achieved with 20% application rate whereas As, Mo, and Cr were slightly stabilized. Toxicity results revealed that leachates collected from treated sediment were less toxic than the control sediment. These results suggest that application of neutralized bauxaline(®) to dredged sediment is an effective approach to manage large quantities of dredged sediments as well as bauxite residue itself. Copyright © 2016 Elsevier Ltd. All rights reserved.

Chronic toxicity and carcinogenicity studies of chromium picolinate monohydrate administered in feed to F344/N rats and B6C3F1 mice for 2 years.

PubMed

Stout, M D; Nyska, A; Collins, B J; Witt, K L; Kissling, G E; Malarkey, D E; Hooth, M J

2009-04-01

Trivalent chromium (Cr(III)) has been proposed to be an essential element, which may increase sensitivity to insulin and thus participate in carbohydrate and lipid metabolism. Humans ingest Cr(III) both as a natural dietary constituent and in dietary supplements taken for weight loss and antidiabetic effects. Chromium picolinate (CP), a widely used supplement, contains Cr(III) chelated with three molecules of picolinic acid and was formulated in an attempt to improve the absorption of Cr(III). In order to examine the potential for CP to induce chronic toxicity and carcinogenicity, the NTP conducted studies of the monohydrate form (CPM) in groups of 50 male and female F344/N rats and B6C3F1 mice exposed in feed to concentrations of 0, 2000, 10,000 or 50,000 ppm for 2 years; exposure concentrations were selected following review of the data from NTP 3-month toxicity studies. Exposure to CPM did not induce biologically significant changes in survival, body weight, feed consumption, or non-neoplastic lesions in rats or mice. In male rats, a statistically significant increase in the incidence of preputial gland adenoma at 10,000 ppm was considered an equivocal finding. CPM was not carcinogenic to female rats or to male or female mice.

Chronic Toxicity and Carcinogenicity Studies of Chromium Picolinate Monohydrate Administered in Feed to F344/N Rats and B6C3F1 Mice for 2 Years

PubMed Central

Stout, M.D.; Nyska, A.; Collins, B.J.; Witt, K.L.; Kissling, G.E.; Malarkey, D.E.; Hooth, M.J.

2009-01-01

Trivalent chromium (Cr(III)) has been proposed to be an essential element, which may increase sensitivity to insulin and thus participate in carbohydrate and lipid metabolism. Humans ingest Cr(III) both as a natural dietary constituent and in dietary supplements taken for weight loss and antidiabetic effects. Chromium picolinate (CP), a widely used supplement, contains Cr(III) chelated with three molecules of picolinic acid and was formulated in an attempt to improve the absorption of Cr(III). In order to examine the potential for CP to induce chronic toxicity and carcinogenicity, the NTP conducted studies of the monohydrate form (CPM) in groups of 50 male and female F344/N rats and B6C3F1 mice exposed in feed to concentrations of 0, 2,000, 10,000 or 50,000 ppm for 2 years; exposure concentrations were selected following review of the data from NTP 3-month toxicity studies. Exposure to CPM did not induce biologically significant changes in survival, body weight, feed consumption, or non-neoplastic lesions in rats or mice. In male rats, a statistically significant increase in the incidence of preputial gland adenoma at 10,000 ppm was considered an equivocal finding. CPM was not carcinogenic to female rats or to male or female mice. PMID:19166900

Investigation of the impact of trace elements on anaerobic volatile fatty acid degradation using a fractional factorial experimental design.

PubMed

Jiang, Ying; Zhang, Yue; Banks, Charles; Heaven, Sonia; Longhurst, Philip

2017-11-15

The requirement of trace elements (TE) in anaerobic digestion process is widely documented. However, little is understood regarding the specific requirement of elements and their critical concentrations under different operating conditions such as substrate characterisation and temperature. In this study, a flask batch trial using fractional factorial design is conducted to investigate volatile fatty acids (VFA) anaerobic degradation rate under the influence of the individual and combined effect of six TEs (Co, Ni, Mo, Se, Fe and W). The experiment inoculated with food waste digestate, spiked with sodium acetate and sodium propionate both to 10 g/l. This is followed by the addition of a selection of the six elements in accordance with a 2 6-2 fractional factorial principle. The experiment is conducted in duplicate and the degradation of VFA is regularly monitored. Factorial effect analysis on the experimental results reveals that within these experimental conditions, Se has a key role in promoting the degradation rates of both acetic and propionic acids; Mo and Co are found to have a modest effect on increasing propionic acid degradation rate. It is also revealed that Ni shows some inhibitory effects on VFA degradation, possibly due to its toxicity. Additionally, regression coefficients for the main and second order effects are calculated to establish regression models for VFA degradation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Topographic PIXE analysis of platinum levels in kidney slices from CIS-platin treated patients

NASA Astrophysics Data System (ADS)

Dikhoff, T. G. M. H.; Van Der Heide, J. A.; McVie, J. G.

1985-05-01

Concentrations of platinum and several other trace elements have been measured exploiting a 50 × 50 μ proton beam for PIXE analysis. The thickness of a selective germanium absorber for the spectral resolution of platinum L β and selenium K α peaks optimized, taking into account the fluorescent X-rays excited in the absorber material. The measurements have been performed in the framework of a project on the assessment of the toxicity of cytostatic platinum compounds. The lateral distributions of platinum in human kidneys and in dog tissues were measured. The highest concentrations of platinum were seen in arterial walls, followed by glomeruli and tubules. Chronic kidney damage may be correlated to this pattern of retention.

Estimation of the bio-accessible fraction of Cr, As, Cd and Pb in locally available bread using on-line continuous leaching method coupled to inductively coupled plasma mass spectrometry.

PubMed

Lamsal, Ram P; Beauchemin, Diane

2015-03-31

A previously developed, efficient and simple on-line leaching method was used to assess the maximum bio-accessible fraction (assuming no synergistic effect from other food and beverage) of potentially toxic elements (Cr, As, Cd and Pb) in whole wheat brown and white bread samples. Artificial saliva, gastric juice and intestinal juice were successively pumped into a mini-column, packed with bread (maintained at 37 °C) connected on-line to the nebulizer of an inductively coupled plasma mass spectrometry (ICP-MS) instrument equipped with a collision-reaction interface (CRI) using hydrogen as reaction gas to minimize carbon- and chlorine-based polyatomic interferences. In contrast to the conventional batch method to which it was compared, this approach provides real-time monitoring of potentially toxic elements that are continuously released during leaching. Mass balance for both methods was verified at the 95% confidence level. Results obtained from the whole wheat brown and white bread showed that the majority of Cr, Cd and Pb was leached by gastric juice but, in contrast, the majority of As was leached by saliva. While there was higher total content for elements in whole wheat bread than in white bread, a higher percentage of elements were bio-accessible in white bread than in whole wheat bread. Both the on-line and batch methods indicate that 40-98% of toxic elements in bread samples are bio-accessible. While comparison of total analyte concentrations with provisional tolerable daily intake values may indicate some serious health concern for children, when accounting for the bio-accessibility of these elements, bread consumption is found to be safe for all ages. Copyright © 2015 Elsevier B.V. All rights reserved.

Selected Issues Associated with the Risk Assessment Process for Pesticides with Persistent, Bioaccumulative, and Toxic Characteristics

EPA Science Inventory

This Scientific Advisory Panel meeting will address selected scientific issues associated with assessing the potential ecological risks resulting from use of a pesticide active ingredient which has persistent, bioaccumulative, and toxic (PBT) characteristics. EPA will pose speci...

Levels of selected carcinogens and toxicants in vapour from electronic cigarettes.

PubMed

Goniewicz, Maciej Lukasz; Knysak, Jakub; Gawron, Michal; Kosmider, Leon; Sobczak, Andrzej; Kurek, Jolanta; Prokopowicz, Adam; Jablonska-Czapla, Magdalena; Rosik-Dulewska, Czeslawa; Havel, Christopher; Jacob, Peyton; Benowitz, Neal

2014-03-01

Electronic cigarettes, also known as e-cigarettes, are devices designed to imitate regular cigarettes and deliver nicotine via inhalation without combusting tobacco. They are purported to deliver nicotine without other toxicants and to be a safer alternative to regular cigarettes. However, little toxicity testing has been performed to evaluate the chemical nature of vapour generated from e-cigarettes. The aim of this study was to screen e-cigarette vapours for content of four groups of potentially toxic and carcinogenic compounds: carbonyls, volatile organic compounds, nitrosamines and heavy metals. Vapours were generated from 12 brands of e-cigarettes and the reference product, the medicinal nicotine inhaler, in controlled conditions using a modified smoking machine. The selected toxic compounds were extracted from vapours into a solid or liquid phase and analysed with chromatographic and spectroscopy methods. We found that the e-cigarette vapours contained some toxic substances. The levels of the toxicants were 9-450 times lower than in cigarette smoke and were, in many cases, comparable with trace amounts found in the reference product. Our findings are consistent with the idea that substituting tobacco cigarettes with e-cigarettes may substantially reduce exposure to selected tobacco-specific toxicants. E-cigarettes as a harm reduction strategy among smokers unwilling to quit, warrants further study. (To view this abstract in Polish and German, please see the supplementary files online.).

Air quality modeling of selected aromatic and non-aromatic air toxics in the Houston urban and industrial airshed

NASA Astrophysics Data System (ADS)

Coarfa, Violeta Florentina

2007-12-01

Air toxics, also called hazardous air pollutants (HAPs), pose a serious threat to human health and the environment. Their study is important in the Houston area, where point sources, mostly located along the Ship Channel, mobile and area sources contribute to large emissions of such toxic pollutants. Previous studies carried out in this area found dangerous levels of different HAPs in the atmosphere. This thesis presents several studies that were performed for the aromatic and non-aromatic air toxics in the HGA. For these studies we developed several tools: (1) a refined chemical mechanism, which explicitly represents 18 aromatic air toxics that were lumped under two model species by the previous version, based on their reactivity with the hydroxyl radical; (2) an engineering version of an existing air toxics photochemical model that enables us to perform much faster long-term simulations compared to the original model, that leads to a 8--9 times improvement in the running time across different computing platforms; (3) a combined emission inventory based on the available emission databases. Using the developed tools, we quantified the mobile source impact on a few selected air toxics, and analyzed the temporal and spatial variation of selected aromatic and non-aromatic air toxics in a few regions within the Houston area; these regions were characterized by different emissions and environmental conditions.

Release of elements to natural water from sediments of Lake Roosevelt, Washington, USA

USGS Publications Warehouse

Paulson, Anthony J.; Cox, Stephen E.

2007-01-01

Reservoir sediments from Lake Roosevelt (WA, USA) that were contaminated with smelter waste discharged into the Columbia River (BC, Canada) were examined using three measures of elemental release reflecting varying degrees of physical mixing and time scales. Aqueous concentrations of Cd, Cu, Pb, and Zn in the interstitial water of reservoir sediments, in the gently stirred overlying waters of incubated sediment cores, and in supernatants of aggressively tumbled slurries of reservoir sediments generally were higher than the concentrations from a reference site. When compared to chronic water-quality criteria, all three measures of release suggest that slag-contaminated sediments near the U.S.-Canadian border are potentially toxic as a result of Cu release and Pb release in two of the three measures. All three measures of Cd release suggest potential toxicity for one site farther down the reservoir, probably contaminated as a result of transport and adsorption of Cd from smelter liquid waste. Releases of Zn and As did not appear to be potentially toxic. Carbonate geochemistry indirectly affects the potential toxicity by increasing water hardness.

Preliminary Assessment of Health Risks of Potentially Toxic Elements in Settled Dust over Beijing Urban Area

PubMed Central

Wan, Dejun; Zhan, Changlin; Yang, Guanglin; Liu, Xingqi; Yang, Jinsong

2016-01-01

To examine levels, health risks, sources, and spatial distributions of potentially toxic elements in settled dust over Beijing urban area, 62 samples were collected mostly from residential building outdoor surfaces, and their <63 μm fractions were measured for 12 potentially toxic elements. The results show that V, Cr, Mn, Co, Ni, and Ba in dust are from predominantly natural sources, whereas Cu, Zn, As, Cd, Sb, and Pb mostly originate from anthropogenic sources. Exposure to these elements in dust has significant non-cancer risks to children but insignificant to adults. Cancer risks of Cr, Co, Ni, As, and Cd via inhalation and dermal contact are below the threshold of 10−6–10−4 but As via dust ingestion shows a tolerable risk. The non-cancer risks to children are contributed mainly (75%) by As, Pb, and Sb, and dominantly (92%) via dust ingestion, with relatively higher risks mainly occurring in the eastern and northeastern Beijing urban areas. Although Cd, Zn, and Cu in dust are heavily affected by anthropogenic sources, their health risks are insignificant. Source appointments suggest that coal burning emissions, the dominant source of As, are likely the largest contributors to the health risk, and traffic-related and industrial emissions are also important because they contribute most of the Pb and Sb in dust. PMID:27187427

Dandelion (Taraxacum officinale) and Agrimony (Agrimonia eupatoria) as Indicators of Geogenic Contamination of Flysch Soils in Eastern Slovakia.

PubMed

Čurlík, Ján; Kolesár, Martin; Ďurža, Ondrej; Hiller, Edgar

2016-04-01

Contents of potentially toxic elements Fe, Mn, Cr, Ni, Co, V, Cu, and Mo were determined in common dandelion (Taraxacum officinale) and agrimony (Agrimonia eupatoria) to show their usefulness as bioindicators of geogenic soil pollution. Both plants were collected on geochemically anomalous soils developed on flysch sedimentary rocks (Paleogene) of Eastern Slovakia, which also are composed of weathered detritus of some ultramafic rocks. Generally, contents of the investigated association of potentially toxic elements are highly increased in these "serpentine"-like soils. Elevated concentrations were detected in both shoots and roots of the plants. The highest values, which exceed world average values for plants, were observed for Ni content. They ranged from 1.7 to 16.3 mg kg(-1) in dandelion and from 1.6 to 22.6 mg kg(-1) in agrimony. Essential elements, such as Mo, Cu, and Mn, were the most concentrated in plants, whereas Co, V, and Cr were the least concentrated. Although the bioindication value of the common dandelion for anthropogenic soil pollution is well known, it is not mentioned for agrimony in literature, and no data exist to indicate the geogenic pollution for both plants. Dandelion and agrimony are widely used as herbal drugs; therefore, our intention also was to point out another fact, namely, possible high uptake of potentially toxic elements by herbal plants growing on similar soils.

Distribution of toxic trace elements in soil/sediment in post-Katrina New Orleans and the Louisiana Delta

USGS Publications Warehouse

Su, T.; Shu, S.; Shi, Honglan; Wang, Jingyuan; Adams, Craig; Witt, Emitt C.

2008-01-01

This study provided a comprehensive assessment of seven toxic trace elements (As, Pb, V, Cr, Cd, Cu, and Hg) in the soil/sediment of Katrina affected greater New Orleans region 1 month after the recession of flood water. Results indicated significant contamination of As and V and non-significant contamination of Cd, Cr, Cu, Hg and Pb at most sampling sites. Compared to the reported EPA Region 6 soil background inorganic levels, except As, the concentrations of other six elements had greatly increased throughout the studied area; St. Bernard Parish and Plaquemines Parish showed greater contamination than other regions. Comparison between pre- and post-Katrina data in similar areas, and data for surface, shallow, and deep samples indicated that the trace element distribution in post-Katrina New Orleans was not obviously attributed to the flooding. This study suggests that more detailed study of As and V contamination at identified locations is needed. ?? 2008 Elsevier Ltd.

Metal and metalloid accumulation in shrews (Soricomorpha, Mammalia) from two protected Mediterranean coastal sites.

PubMed

Sánchez-Chardi, Alejandro; López-Fuster, María José

2009-04-01

Although ecotoxicological data on heavy metals are abundant, information on other potentially toxic elements with attributed deficiency and/or toxic disturbances is scarce. Here we quantify zinc, copper, iron, manganese, chromium, molybdenum, strontium, barium, and boron in bones of greater white-toothed shrews, Crocidura russula, inhabiting two protected Mediterranean coastal sites: the Ebro Delta, a wetland impacted by human activities, and the Medas Islands, a reference site. Natural and anthropogenic inputs significantly increase Fe, Mn, Mo, Sr, Ba, and B in specimens from the Ebro Delta, whereas Cu and Cr were higher in Medas' shrews. Principal component analysis allowed complete separation between sites along the first two axes in particular due to B, Sr, and Cu. This study provides metal reference values in bones of insectivores, explores their variability and bioaccumulation patterns in depth, and assesses the potential environmental risk and toxicity for biota exposed to the above elements.

A glimpse on biological activities of tellurium compounds.

PubMed

Cunha, Rodrigo L O R; Gouvea, Iuri E; Juliano, Luiz

2009-09-01

Tellurium is a rare element which has been regarded as a toxic, non-essential trace element and its biological role is not clearly established to date. Besides of that, the biological effects of elemental tellurium and some of its inorganic and organic derivatives have been studied, leading to a set of interesting and promising applications. As an example, it can be highlighted the uses of alkali-metal tellurites and tellurates in microbiology, the antioxidant effects of organotellurides and diorganoditellurides and the immunomodulatory effects of the non-toxic inorganic tellurane, named AS-101, and the plethora of its uses. Inasmuch, the nascent applications of organic telluranes (organotelluranes) as protease inhibitors and its applications in disease models are the most recent contribution to the scenario of the biological effects and applications of tellurium and its compounds discussed in this manuscript.

Toxicity of selected insecticides applied to western spruce budworm

Treesearch

Jacqueline L. Robertson; Nancy L. Gillette; Melvin Look; Barbara A. Lucas; Robert L. Lyon

1975-01-01

The contact toxicity of 100 insecticides to last stage larvae of Choristoneura occidentalis Freeman was tested by topical application in a 10-yr series of screening experiments. Pyrethroids were generally the most toxic group of chemicals tested. Compounds more toxic than the standard, mexacarbate, at Ld50 were:...

In Vitro and In Vivo Toxicity Profiling of Ammonium-Based Deep Eutectic Solvents

PubMed Central

Hayyan, Maan; Looi, Chung Yeng; Hayyan, Adeeb; Wong, Won Fen; Hashim, Mohd Ali

2015-01-01

The cytotoxic potential of ammonium-based deep eutectic solvents (DESs) with four hydrogen bond donors, namely glycerine (Gl), ethylene glycol (EG), triethylene glycol (TEG) and urea (U) were investigated. The toxicity of DESs was examined using In Vitro cell lines and In Vivo animal model. IC50 and selectivity index were determined for the DESs, their individual components and their combinations as aqueous solutions for comparison purposes. The cytotoxicity effect of DESs varied depending on cell lines. The IC50 for the GlDES, EGDES, UDES and TEGDES followed the sequence of TEGDES< GlDES< EGDES< UDES for OKF6, MCF-7, A375, HT29 and H413, respectively. GlDES was selective against MCF-7 and A375, EGDES was selective against MCF-7, PC3, HepG2 and HT29, UDES was selective against MCF-7, PC3, HepG2 and HT29, and TEGDES was selective against MCF-7 and A375. However, acute toxicity studies using ICR mice showed that these DESs were relatively toxic in comparison to their individual components. DES did not cause DNA damage, but it could enhance ROS production and induce apoptosis in treated cancer cells as evidenced by marked LDH release. Furthermore, the examined DESs showed less cytotoxicity compared with ionic liquids. To the best of our knowledge, this is the first time that combined In Vitro and In Vivo toxicity profiles of DESs were being demonstrated, raising the toxicity issue of these neoteric mixtures and their potential applicability to be used for therapeutic purposes. PMID:25679975

Mechanism Profiling of Hepatotoxicity Caused by Oxidative Stress Using Antioxidant Response Element Reporter Gene Assay Models and Big Data.

PubMed

Kim, Marlene Thai; Huang, Ruili; Sedykh, Alexander; Wang, Wenyi; Xia, Menghang; Zhu, Hao

2016-05-01

Hepatotoxicity accounts for a substantial number of drugs being withdrawn from the market. Using traditional animal models to detect hepatotoxicity is expensive and time-consuming. Alternative in vitro methods, in particular cell-based high-throughput screening (HTS) studies, have provided the research community with a large amount of data from toxicity assays. Among the various assays used to screen potential toxicants is the antioxidant response element beta lactamase reporter gene assay (ARE-bla), which identifies chemicals that have the potential to induce oxidative stress and was used to test > 10,000 compounds from the Tox21 program. The ARE-bla computational model and HTS data from a big data source (PubChem) were used to profile environmental and pharmaceutical compounds with hepatotoxicity data. Quantitative structure-activity relationship (QSAR) models were developed based on ARE-bla data. The models predicted the potential oxidative stress response for known liver toxicants when no ARE-bla data were available. Liver toxicants were used as probe compounds to search PubChem Bioassay and generate a response profile, which contained thousands of bioassays (> 10 million data points). By ranking the in vitro-in vivo correlations (IVIVCs), the most relevant bioassay(s) related to hepatotoxicity were identified. The liver toxicants profile contained the ARE-bla and relevant PubChem assays. Potential toxicophores for well-known toxicants were created by identifying chemical features that existed only in compounds with high IVIVCs. Profiling chemical IVIVCs created an opportunity to fully explore the source-to-outcome continuum of modern experimental toxicology using cheminformatics approaches and big data sources. Kim MT, Huang R, Sedykh A, Wang W, Xia M, Zhu H. 2016. Mechanism profiling of hepatotoxicity caused by oxidative stress using antioxidant response element reporter gene assay models and big data. Environ Health Perspect 124:634-641; http://dx.doi.org/10.1289/ehp.1509763.

Mechanism Profiling of Hepatotoxicity Caused by Oxidative Stress Using Antioxidant Response Element Reporter Gene Assay Models and Big Data

PubMed Central

Kim, Marlene Thai; Huang, Ruili; Sedykh, Alexander; Wang, Wenyi; Xia, Menghang; Zhu, Hao

2015-01-01

Background: Hepatotoxicity accounts for a substantial number of drugs being withdrawn from the market. Using traditional animal models to detect hepatotoxicity is expensive and time-consuming. Alternative in vitro methods, in particular cell-based high-throughput screening (HTS) studies, have provided the research community with a large amount of data from toxicity assays. Among the various assays used to screen potential toxicants is the antioxidant response element beta lactamase reporter gene assay (ARE-bla), which identifies chemicals that have the potential to induce oxidative stress and was used to test > 10,000 compounds from the Tox21 program. Objective: The ARE-bla computational model and HTS data from a big data source (PubChem) were used to profile environmental and pharmaceutical compounds with hepatotoxicity data. Methods: Quantitative structure–activity relationship (QSAR) models were developed based on ARE-bla data. The models predicted the potential oxidative stress response for known liver toxicants when no ARE-bla data were available. Liver toxicants were used as probe compounds to search PubChem Bioassay and generate a response profile, which contained thousands of bioassays (> 10 million data points). By ranking the in vitro–in vivo correlations (IVIVCs), the most relevant bioassay(s) related to hepatotoxicity were identified. Results: The liver toxicants profile contained the ARE-bla and relevant PubChem assays. Potential toxicophores for well-known toxicants were created by identifying chemical features that existed only in compounds with high IVIVCs. Conclusion: Profiling chemical IVIVCs created an opportunity to fully explore the source-to-outcome continuum of modern experimental toxicology using cheminformatics approaches and big data sources. Citation: Kim MT, Huang R, Sedykh A, Wang W, Xia M, Zhu H. 2016. Mechanism profiling of hepatotoxicity caused by oxidative stress using antioxidant response element reporter gene assay models and big data. Environ Health Perspect 124:634–641; http://dx.doi.org/10.1289/ehp.1509763 PMID:26383846

Source identification, environmental risk assessment and human health risks associated with toxic elements present in a coastal industrial environment, India.

PubMed

Satapathy, Shreemayee; Panda, C R

2018-03-26

This study investigated the source and contamination levels of toxic elements (Cd, Cr, As, Pb, Ni and Hg) present in a coastal environment, Paradip-an industrial hub of the east coast of India. The ecological risk assessment indices and human exposure models were used to evaluate the pollution status. Enrichment factor indicated that all the metal(loid)s found in the sediment are mostly derived from the anthropogenic source. According to the sediment quality quotient, 8.33% of sediments have crossed the ERM limit for Ni that can be fatal to biota. Meanwhile, 66.66, 41.66 and 8.33% of sediments have exceeded PEL range for Cr, Ni and As, respectively, that can register frequent lethal toxicity to benthic biota. As had the highest potential ecological harm coefficient (Er f  > 80), and Hg had moderate ecological harm coefficient (40 < Er f  < 80). Summarily, the sediment quality of this site is moderate to heavily toxic to benthic organisms. The concentration of toxic metals in seawater was below the permissible limit (CCC and CMC) set by USEPA indicating that water is relatively safer for free floating aquatic biota. The health risk index of toxic metal (loid)s present in soils of the residential sites has confirmed that there is a severe non-carcinogenic threat for children (HI child > 1) and a borderline carcinogenic risk for both adult and children. THQ Cr possesses highest non-carcinogenic threat, which contributed approximately 50% to HI followed by THQ As . The contribution of carcinogenic risk of chromium (CR Cr ) to TCR is approximately 60%. Cr is the significant contaminant of this site that has highest health effects. Highest exposure risks were associated with ingestion pathway accounting for about 85% of the total for most of the elements.

Occurrence and concentrations of selected trace elements, halogenated organic compounds, and polycyclic aromatic hydrocarbons in streambed sediments and results of water-toxicity testing in Westside Creeks and the San Antonio River, San Antonio, Texas, 2014

USGS Publications Warehouse

Crow, Cassi L.; Wilson, Jennifer T.; Kunz, James L.

2016-12-01

Sediment samples and samples for water-toxicity testing were collected during 2014 from several streams in San Antonio, Texas, known locally as the Westside Creeks (Alazán, Apache, Martínez, and San Pedro Creeks) and from the San Antonio River. Samples were collected during base flow and after periods of stormwater runoff (poststorm conditions) to determine baseline sediment- and water-quality conditions. Streambed-sediment samples were analyzed for selected constituents, including trace elements and organic contaminants such as pesticides, polychlorinated biphenyls (PCBs), brominated flame retardants, and polycyclic aromatic hydrocarbons (PAHs). Potential risks of contaminants in sediment were evaluated by comparing concentrations of contaminants in sediment to two effects-based sediment-quality guidelines: (1) a lower level, called the threshold effect concentration, below which, harmful effects to benthic biota are not expected, and (2) a higher level, the probable effect concentration (PEC), above which harmful effects are expected to occur frequently. Samples for water-toxicity testing were collected from each stream to provide information about fish toxicity in the study area. The trace metal lead was detected at potentially toxic concentrations greater than the PEC in both the base-flow and poststorm samples collected at two sites sampled on San Pedro Creek. The PECs for the pesticides dichlorodiphenyldichloroethane, dichlorodiphenyldichloroethylene, dichlorodiphenyltrichloroethane, and chlordane were exceeded in some of the samples at the same two sites on San Pedro Creek. Brominated flame retardants and polybrominated diphenyl ether (PBDE) 85, 153, and 154 were found in all streambed-sediment samples. Federal Environmental Quality Guidelines established by Environment Canada for PBDE 99 and PBDE 100 were exceeded in all samples in which PBDE 99 was detected and in a majority of the samples in which PBDE 100 was detected; the greatest concentrations occurred in samples collected at the same two sites on San Pedro Creek where the samples containing elevated lead and pesticide concentrations were collected. All concentrations of total PCBs (computed as the sum of the 18 reported PCB congeners) in the individual streambed-sediment samples were less than the threshold effect concentration, but the concentrations were elevated in the two sites on San Pedro Creek compared to concentrations at other sites. At one site on Apache Creek, 6 of the individual PAHs measured in the sample collected during base-flow conditions exceeded the PECs and 8 of the 9 PECs were exceeded in the sample collected during poststorm conditions. The total PAH concentration in the sample collected at the site during poststorm conditions was 3.3 times greater than the PEC developed for total PAHs. Average PAH profiles computed for base-flow samples and poststorm samples most closely resemble the parking lot coal-tar sealcoat dust PAH source profile, defined as the average PAH concentrations in dust swept from parking lots in six cities in the United States that were sealed with a black, viscous liquid containing coal-tar pitch. Six of ten water samples collected during base-flow conditions caused reductions in Pimephales promelas (fathead minnow) survival and were considered to be toxic.

Sediment toxicity identification evaluation (TIE) studies at marine sites suspected of ordnance contamination

USGS Publications Warehouse

Carr, R.S.; Nipper, M.; Biedenbach, J.M.; Hooten, R.L.; Miller, K.; Saepoff, S.

2001-01-01

A sediment quality assessment survey and subsequent toxicity identification evaluation (TIE) study was conducted at several sites in Puget Sound, Washington. The sites were previously suspected of contamination with ordnance compounds. The initial survey employed sea urchin porewater toxicity tests to locate the most toxic stations. Sediments from the most toxic stations were selected for comprehensive chemical analyses. Based on the combined information from the toxicity and chemical data, three adjacent stations in Ostrich Bay were selected for the TIE study. The results of the phase I TIE suggested that organics and metals were primarily responsible for the observed toxicity in the sea urchin fertilization test. In addition to these contaminants, ammonia was also contributing to the toxicity for the sea urchin embryological development test. The phase II TIE study isolated the majority of the toxicity in the fraction containing nonpolar organics with high log Kow, but chemical analyses failed to identify a compound present at a concentration high enough to be responsible for the observed toxicity. The data suggest that some organic or organometallic contaminant(s) that were not included in the comprehensive suite of chemical analyses caused the observed toxicological responses.

Chemical and sewage sludge co-incineration in a full-scale MSW incinerator: toxic trace element mass balance.

PubMed

Biganzoli, Laura; Grosso, Mario; Giugliano, Michele; Campolunghi, Manuel

2012-10-01

Co-incineration of sludges with MSW is a quite common practice in Europe. This paper illustrates a case of co-incineration of both sewage sludges and chemical sludges, the latter obtained from drinking water production, in a waste-to-energy (WTE) plant located in northern Italy and equipped with a grate furnace, and compares the toxic trace elements mass balance with and without the co-incineration of sludges. The results show that co-incineration of sewage and chemical sludges does not result in an increase of toxic trace elements the total release in environment, with the exception of arsenic, whose total release increases from 1 mg t(fuel) (-1) during standard operation to 3 mg t(fuel) (-1) when sludges are co-incinerated. The increase of arsenic release is, however, attributable to the sole bottom ashes, where its concentration is five times higher during sludge co-incineration. No variation is observed for arsenic release at the stack. This fact is a further guarantee that the co-incineration of sludges, when performed in a state-of-the-art WTE plant, does not have negative effects on the atmospheric environment.

Optimisation of the supercritical extraction of toxic elements in fish oil.

PubMed

Hajeb, P; Jinap, S; Shakibazadeh, Sh; Afsah-Hejri, L; Mohebbi, G H; Zaidul, I S M

2014-01-01

This study aims to optimise the operating conditions for the supercritical fluid extraction (SFE) of toxic elements from fish oil. The SFE operating parameters of pressure, temperature, CO2 flow rate and extraction time were optimised using a central composite design (CCD) of response surface methodology (RSM). High coefficients of determination (R²) (0.897-0.988) for the predicted response surface models confirmed a satisfactory adjustment of the polynomial regression models with the operation conditions. The results showed that the linear and quadratic terms of pressure and temperature were the most significant (p < 0.05) variables affecting the overall responses. The optimum conditions for the simultaneous elimination of toxic elements comprised a pressure of 61 MPa, a temperature of 39.8ºC, a CO₂ flow rate of 3.7 ml min⁻¹ and an extraction time of 4 h. These optimised SFE conditions were able to produce fish oil with the contents of lead, cadmium, arsenic and mercury reduced by up to 98.3%, 96.1%, 94.9% and 93.7%, respectively. The fish oil extracted under the optimised SFE operating conditions was of good quality in terms of its fatty acid constituents.

Comparative uptake study of arsenic, boron, copper, manganese and zinc from water by different green microalgae.

PubMed

Saavedra, Ricardo; Muñoz, Raúl; Taboada, María Elisa; Vega, Marisol; Bolado, Silvia

2018-04-26

This work represents a comparative uptake study of the toxic elements arsenic, boron, copper, manganese and zinc in monometallic and multimetallic solutions by four green microalgae species (Chlamydomonas reinhardtii, Chlorella vulgaris, Scenedesmus almeriensis and an indigenous Chlorophyceae spp.), evaluating the effect of pH and contact time. Maximum removal efficiencies for each toxic element were 99.4% for Mn (C. vulgaris, pH 7.0, 3 h), 91.9% for Zn (Chlorophyceae spp., pH 5.5, 3 h), 88% for Cu (Chlorophyceae spp., pH 7.0, 10 min), 40.7% for As (S. almeriensis, pH 9.5, 3 h) and 38.6% for B (S. almeriensis, pH 5.5, 10 min). B removal efficiencies decreased remarkably in multimetallic solutions (down to 0.2% in C. reinhardtii), except for Chlorophyceae spp., the only species isolated from a polluted environment. FTIR spectra shown the highest interactions for As (1150-1300 cm -1 ) and Cu (3300, 1741, 1535, 1350-1400 cm -1 ). Results confirm microalgae biomass as a potential biosorbent for toxic elements. Copyright © 2018 Elsevier Ltd. All rights reserved.

Metal release from contaminated leaf litter and leachate toxicity for the freshwater crustacean Gammarus fossarum.

PubMed

Maunoury-Danger, Florence; Felten, Vincent; Bojic, Clément; Fraysse, Fabrice; Cosin Ponce, Mar; Dedourge-Geffard, Odile; Geffard, Alain; Guérold, François; Danger, Michael

2018-04-01

Industrialization has left large surfaces of contaminated soils, which may act as a source of pollution for contiguous ecosystems, either terrestrial or aquatic. When polluted sites are recolonized by plants, dispersion of leaf litter might represent a non-negligible source of contaminants, especially metals. To evaluate the risks associated to contaminated leaf litter dispersion in aquatic ecosystems, we first measured the dynamics of metal loss from leaf litter during a 48-h experimental leaching. We used aspen (Populus tremula L.), a common tree species on these polluted sites, and collected leaf litter on three polluted sites (settling pond of a former steel mill) and three control sites situated in the same geographic area. Then, toxicity tests were carried out on individuals of a key detritivore species widely used in ecotoxicology tests, Gammarus fossarum (Crustacea, Amphipoda), with uncontaminated and contaminated leaf litter leachates, using a battery of biomarkers selected for their sensitivity to metallic stress. Leaf litters collected on polluted sites exhibited not only significantly higher cadmium and zinc concentrations but also lower lignin contents. All leaf litters released high amounts of chemical elements during the leaching process, especially potassium and magnesium, and, in a lesser extent, phosphorus, calcium, and trace metals (copper, cadmium, and zinc but not lead). Toxicity tests revealed that the most important toxic effects measured on G. fossarum were due to leaf litter leachates by themselves, whatever the origin of litter (from polluted or control sites), confirming the toxicity of such substances, probably due to their high content in phenolic compounds. Small additional toxic effects of leachates from contaminated leaf litters were only evidenced on gammarid lipid peroxidation, indicating that contaminated leaf litter leachates might be slightly more toxic than uncontaminated ones, but in a very reduced manner. Further studies will be required to verify if these patterns are generalizable to other species and to investigate the effects of contaminated leaf litter ingestion by consumers on aquatic food webs. Nevertheless, our results do not permit to exclude potential chronic effects of an exposure to contaminated leaf litter leachates in aquatic ecosystems.

Application of Solid Phase Microextraction Coupled with Gas Chromatography/Mass Spectrometry as a Rapid Method for Field Sampling and Analysis of Chemical Warfare Agents and Toxic Industrial Chemicals

DTIC Science & Technology

2003-01-01

PHASE MICROEXTRACTION COUPLED WITH GAS CHROMATOGRAPHY/MASS SPECTROMETRY AS A RAPID METHOD FOR FIELD SAMPLING AND ANALYSIS OF CHEMICAL WARFARE AGENTS...SAMPLING AND ANALYSIS OF CHEMICAL WARFARE AGENTS AND TOXIC INDUSTRIAL CHEMICALS 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...GAS CHROMATOGRAPHY/MASS SPECTROMETRY AS A RAPID METHOD FOR FIELD SAMPLING AND ANALYSIS OF CHEMICAL WARFARE AGENTS AND TOXIC INDUSTRIAL CHEMICALS

Genotoxicity testing on the international space station: Preparatory work on the SOS-LUX test as part of the space experiment TRIPLE-LUX

NASA Astrophysics Data System (ADS)

Stojicic, Nevena; Walrafen, David; Baumstark-Khan, Christa; Rabbow, Elke; Rettberg, Petra; Weisshaar, Maria-Paz; Horneck, Gerda

Harmful environmental factors - namely ionizing radiation - will continue to influence future manned space missions. The Radiation Biology Unit at the German Aerospace Center (DLR) develops cellular monitoring systems, which include bacterial and mammalian cell systems capable of recognizing DNA damage as a consequence of the presence of genotoxic conditions. Such a bioassay is the SOS-LUX test, which represents the radiobiological part of the German space experiment "Gene, immune and cellular responses to single and combined space flight conditions (TRIPLE-LUX)" which has been selected by the IDI/USRA Peer Review Panel for NASA/ESA to be performed on the International Space Station (ISS). It will supply basic information on the genotoxic response to radiation applied in microgravity. The biological end-point under investigation will depend on the bacterial SOS response brought about by genetically modified bacteria that are transformed with the pSWITCH plasmid (constructed from the plasmids pPLS-1 and pGFPuv). The luminescent/fluorescent bioassay SWITCH (SWITCH: Salmonella Weighting of Induced Toxicity Cyto/GenoTox for Human Health) as successor of the SOS-LUX test for rapid toxicity (genotoxicity and cytotoxicity) testing, makes use of two sensing and reporting systems for the two biological endpoints under investigation: the SOS-LUX test and the LAC- Fluoro test. The SWITCH plasmid carries the promoterless lux operon of Photobacterium leiognathi as reporter element under the control of the DNA-damage-dependent SOS promoter of ColD as sensor element (for genotoxicity testing) and the sequences for a hybrid protein consisting of β-galactosidase and GFPuv of Aequorea victoria as reporter element under the control of the (in Salmonella constitutively active) LAC promoter of Escherichia coli as sensor element (for cytotoxicity testing). The system has worked properly for terrestrial applications during the first experiments. Experiments using X-rays and UV radiation of various qualities (from UVC to UVA) have given insights into cellular mechanisms relevant for estimation of health risks, resulting from exposure of astronauts to the extraordinary radiation environment of space.

Germanium and Rare Earth Element accumulation in woody bioenergy crops

NASA Astrophysics Data System (ADS)

Hentschel, Werner

2016-04-01

Germanium and REEs are strategic elements that are used for high tech devices and engineered systems, however these elements are hardly concentrated into mineable ore deposits. Since these elements occur widely dispersed in the earth crust with concentrations of several mgṡkg-1 (Ge 1.6 mgṡkg-1, Nd 25 mgṡkg-1) a new possibility to gain these elements could be phytomining, a technique that uses plants to extract elements from soils via their roots. Since knowledge about accumulating plant species is quite limited we conducted research on the concentrations of strategic elements in wood and leaves of fast growing tree species (Salix spec., Populus spec., Betula pendula, Alnus glutinosa, Fraxinus excelsior, Acer pseudoplatanus). In total 35 study sites were selected in the mining affected area around Freiberg (Saxony, Germany), differing in their species composition and degree of contamination with toxic trace metals (Pb, As, Cd). On each site plant tissues (wood and leaves, respectively) of different species were sampled. In addition soil samples were taken from a soil depth of 0 - 30 cm and 30 - 60 cm. The aim of our work was to investigate correlations between the concentrations of the target elements in plant tissues and soil characteristics like pH, texture, nutrients and concentrations in six operationally defined soil fractions (mobile, acid soluble, oxidizable, amorphic oxides, crystalline oxides, residual or siliceous). Concentrations of elements in soil extracts and plant tissues were measured with ICP-MS. The element Nd was selected as representative for the group of REEs, since this element showed a high correlation with the concentrations of the other REE We found that the concentration of Nd in the leaves (0.31 mgṡkg-1Nd) were several times higher than in herbaceous species (0.05 mgṡkg-1 Nd). The concentration of Ge in leaves were ten times lower than that of Nd whereas in herbaceous species Nd and Ge were in equal magnitude. Within the tree species Populus spec. (0.77 mgṡkg-1) and Salix spec. (0.36 mgṡkg-1) showed by far the highest concentrations of Nd in leaves. Fraxinus excelsior (0.10 mgṡkg-1) and Betula pendula (0.06 mgṡkg-1) feature the lowest concentrations of Nd in leaves. We found significant correlations between the concentration of the target elements in the plant tissue and the concentration of these elements in the first steps of the sequential extraction of the soil samples. These studies have been carried out in the framework of the PhytoGerm project financed by the Federal Ministry of Education and Research, Germany.

Trace element concentrations in feathers and blood of Northern goshawk (Accipiter gentilis) nestlings from Norway and Spain.

PubMed

Dolan, Kevin J; Ciesielski, Tomasz M; Lierhagen, Syverin; Eulaers, Igor; Nygård, Torgeir; Johnsen, Trond V; Gómez-Ramírez, Pilar; García-Fernández, Antonio J; Bustnes, Jan O; Ortiz-Santaliestra, Manuel E; Jaspers, Veerle L B

2017-10-01

Information on trace element pollution in the terrestrial environment and its biota is limited compared to the marine environment. In the present study, we collected body feathers and blood of 37 Northern goshawk (Accipiter gentilis) nestlings from Tromsø (northern Norway), Trondheim (central Norway), and Murcia (southeastern Spain) to study regional exposure, hypothesizing the potential health risks of metals and other trace elements. Blood and body feathers were analyzed by a high resolution inductively coupled plasma mass spectrometer (HR-ICP-MS) for aluminum (Al), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), mercury (Hg) and lead (Pb). The influence of regional differences, urbanization and agricultural land usage in proximity to the nesting Northern goshawks was investigated using particular spatial analysis techniques. Most trace elements were detected below literature blood toxicity thresholds, except for elevated concentrations (mean ± SD µgml -1 ww) found for Zn (5.4 ± 1.5), Cd (0.00023 ± 0.0002), and Hg (0.021 ± 0.01). Corresponding mean concentrations in feathers (mean ± SD µgg -1 dw) were 82.0 ± 12.4, 0.0018 ± 0.002, and 0.26 ± 0.2 for Zn, Cd and Hg respectively. Multiple linear regressions indicated region was a significant factor influencing Al, Zn, Se and Hg feather concentrations. Blood Cd and Hg concentrations were significantly influenced by agricultural land cover. Urbanization did not have a significant impact on trace element concentrations in either blood or feathers. Overall metal and trace element levels do not indicate a high risk for toxic effects in the nestlings. Levels of Cd in Tromsø and Hg in Trondheim were however above sub-lethal toxic threshold levels. For holistic risk assessment purposes it is important that the concentrations found in the nestlings of this study indicate that terrestrial raptors are exposed to various trace elements. Copyright © 2017 Elsevier Inc. All rights reserved.

Determination of the acute toxicity of isoniazid to three invasive carp species and rainbow trout in static exposures

USGS Publications Warehouse

Schreier, Theresa M.; Hubert, Terrance D.

2015-01-01

Three invasive fishes of considerable concern to aquatic resource managers are the Hypophthalmichthys nobilis (bighead carp),Hypophthalmichthys molitrix (silver carp), and Ctenopharyngodon idella (grass carp), collectively known as Asian carps. There is a need for an effective chemical control agent for Asian carps. Isoniazid was identified as a potential toxicant for grass carp. The selective toxicity of isoniazid to grass carp was verified as a response to an anecdotal report received in 2013. In addition, the toxicity of isoniazid to bighead carp, silver carp, and Oncorhynchus mykiss (rainbow trout) was evaluated. Isoniazid was not toxic to grass carp at the reported anecdotal concentration, which was 13 milligrams per liter. Isoniazid (130 milligrams per liter) was not selectively toxic to bighead carp, silver carp, or grass carp when compared to rainbow trout.

Toxic metal interactions affect the bioaccumulation and dietary intake of macro- and micro-nutrients.

PubMed

Khan, Anwarzeb; Khan, Sardar; Alam, Mehboob; Khan, Muhammad Amjad; Aamir, Muhammad; Qamar, Zahir; Ur Rehman, Zahir; Perveen, Sajida

2016-03-01

The present study was conducted to evaluate the effects of heavy metals (cadmium (Cd), lead (Pb) and Cd-Pb mix) on bioaccumulation of different nutrients. Three plant species including potato, tomato and lettuce were grown in pots containing soil contaminated with Cd, Pb and Cd-Pb mix at four different levels. The edible portions of each plant were analysed for Cd, Pb and different macro- and micro-nutrients including protein, vitamin C, nitrogen (N), phosphorous (P), potassium (K), iron (Fe), manganese (Mn), calcium (Ca) and magnesium (Mg). Results indicated significant variations in selected elemental concentrations in all the three plants grown in different treatments. The projected daily dietary intake values of selected metals were significant (P < 0.001) for Fe, Mn, Ca and Mg but not significant for protein, vitamin C, N and P. The elemental contribution to Recommended Dietary Allowance (RDA) was significant for Mn. Similarly, Fe and Mg also showed substantial contribution to RDA, while Ca, N, P, K, protein and vitamin C showed the minimal contribution for different age groups. This study suggests that vegetables cultivated on Cd and Pb contaminated soil may significantly affect their quality, and the consumption of such vegetables may result in substantial negative effects on nutritional composition of the consumer body. Long term and continuous use of contaminated vegetables may result in malnutrition. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bioaccumulation of metals and metalloids in medicinal plant Ipomoea pes-caprae from areas impacted by tsunami.

PubMed

Kozak, Lidia; Kokociński, Mikołaj; Niedzielski, Przemysław; Lorenc, Stanisław

2015-02-01

Tsunami events may have an enormous impact on the functioning of aquatic and terrestrial ecosystems by altering various relationships with biotic components. Concentrations of acid-leachable fractions of heavy metals and metalloids in soils and plant samples from areas affected by the December 2004 tsunami in Thailand were determined. Ipomoea pes-caprae, a common plant species growing along the seashore of this region, and frequently used in folk medicine, was selected to assess the presence of selected elements. Elevated amounts of Cd, Pb, Zn, and As in soil samples, and Pb, Zn, As, Se, Cr, and Ni in plant samples were determined from the tsunami-impacted regions for comparison with reference locations. The flowers of Ipomoea pes-caprae contained the highest amounts of these metals, followed by its leaves, and stems. In addition, its bioaccumulation factor (BAF) supports this capability of high metal uptake by Ipomoea pes-caprae from the areas affected by the tsunami in comparison with a reference site. This uptake was followed by the translocation of these elements to the various plant components. The presence of these toxic metals in Ipomoea pes-caprae growing in contaminated soils should be a concern of those who use this plant for medicinal purposes. Further studies on the content of heavy metals and metalloids in this plant in relation to human health concerns are recommended. © 2014 SETAC.

Microbiological stimulation of phytoremediation process using Salvinia natans to mercury contamined water

NASA Astrophysics Data System (ADS)

Filyarovskaya, Viktoriya; Sitarska, Magdalena; Traczewska, Teodora; Wolf, Mirela

2017-11-01

An alternative to traditional cleaning methods of heavy metals in the water environment is phytoremediation. They efficiency depends on used technological process conditions as well as plant species. One of the most dangerous metallic elements mercury plays a particular role, which is a trace element and a physiologically foreign in living organisms. Mercury has a high degree of toxicity with strong affinity to thiol groups. This may cause an adverse effect on the enzymatic processes and consequently inhibiting the physiological functions. Because of high risk for human health, water environment treatment from mercury is essential proecological action. Mercury removal studies were conducted using Salvinia natans pleustofit, sampled from its natural water environment. In the first step, epiphytic bacteria, which was resistant to high concentrations of mercury (0,6 mgHg/l), was isolated from the plant and than selected by the tiles gradient mthod. In the next step, the identification using molecular biology methods was made. In the following step plant Salvinia natans was exposure to high levels of mercury in the presence of the three isolated Pseudomonas strains with exceptional resistance characteristics to environmental factors. Has been found a positive bacteria effect on the plant condition because the selected strains belong to Pseudomonas species producing materials supporting plant growth. The use of microbial stimulation to phytoremediation by hyperaccumulator Salvinia natans can multiply the effectiveness of the process.

BIOLOGICAL MONITORING OF TOXIC TRACE METALS. VOLUME 2. TOXIC TRACE METALS IN PLANTS AND ANIMALS OF THE WORLD. PART II

EPA Science Inventory

The needs and priorities in using biological accumulator organisms for monitoring toxic trace metals in plants and animals are analyzed. The toxic trace metals selected for study are antimony, arsenic, beryllium, boron, cadmium, chromium, cobalt, copper, lead, mercury, nickel, se...

BIOLOGICAL MONITORING OF TOXIC TRACE METALS. VOLUME 2. TOXIC TRACE METALS IN PLANTS AND ANIMALS OF THE WORLD. PART I

EPA Science Inventory

The needs and priorities in using biological accumulator organisms for monitoring toxic trace metals in plants and animals are analyzed. The toxic trace metals selected for study are antimony, arsenic, beryllium, boron, cadmium, chromium, cobalt, copper, lead, mercury, nickel, se...

Controls on the chemical composition of saline surface crusts and emitted dust from a wet playa in the Mojave Desert (USA)

USGS Publications Warehouse

Goldstein, Harland L.; Breit, George N.; Reynolds, Richard L.

2017-01-01

Saline-surface crusts and their compositions at ephemeral, dry, and drying lakes are important products of arid-land processes. Detailed understanding is lacking, however, about interactions among locally variable hydrogeologic conditions, compositional control of groundwater on vadose zone and surface salts, and dust composition. Chemical and physical data from groundwater, sediments, and salts reveal compositional controls on saline-surface crusts across a wet playa, Mojave Desert, with bearing on similar settings elsewhere. The compositions of chemically and isotopically distinctive shallow (<3 m) water masses are recorded in the composition of associated salts. In areas with deeper and more saline groundwater, however, not all ions are transported through the vadose zone. Retention of arsenic and other elements in the vadose zone diminishes the concentrations of potentially toxic elements in surface salts, but creates a reservoir of these elements that may be brought to the surface during wetter conditions or by human disturbance. Selective wind-erosion loss of sulfate salts was identified by the compositional contrast between surface salt crusts and underlying groundwater. At the sub-basin scale, compositional links exist among groundwater, salt crusts, and dust from wet playas. Across the study basin, however, lateral variations in groundwater and solid-salt compositions are produced by hydrogeologic heterogeneity.

Rare earth elements in human and animal health: State of art and research priorities

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

Pagano, Giovanni, E-mail: gbpagano@tin.it; Aliberti, Francesco; Guida, Marco

Background: A number of applications have been developed using rare earth elements (REE), implying several human exposures and raising unsolved questions as to REE-associated health effects. Methods: A MedLine survey was retrieved from early reports (1980s) up to June 2015, focused on human and animal exposures to REE. Literature from animal models was selected focusing on REE-associated health effects. Results: Some REE occupational exposures, in jobs such as glass polishers, photoengravers and movie projectionists showed a few case reports on health effects affecting the respiratory system. No case-control or cohort studies of occupational REE exposures were retrieved. Environmental exposures havemore » been biomonitored in populations residing in REE mining areas, showing REE accumulation. The case for a iatrogenic REE exposure was raised by the use of gadolinium-based contrast agents for nuclear magnetic resonance. Animal toxicity studies have shown REE toxicity, affecting a number of endpoints in liver, lungs and blood. On the other hand, the use of REE as feed additives in livestock is referred as a safe and promising device in zootechnical activities, possibly suggesting a hormetic effect both known for REE and for other xenobiotics. Thus, investigations on long-term exposures and observations are warranted. Conclusion: The state of art provides a limited definition of the health effects in occupationally or environmentally REE-exposed human populations. Research priorities should be addressed to case-control or cohort studies of REE-exposed humans and to life-long animal experiments. - Highlights: • An extensive number of activities have been developed utilizing rare earth elements (REE). • The literature of REE-associated health effects in humans, and on animal studies is reviewed. • The main literature gaps are discussed, in epidemiological and in animal studies. • Prospects studies are suggested, aimed at evaluating long-term effects of REE exposures. • The relevance of REE-related hormesis, speciation and acidic pollution are discussed.« less

Temporal dissolution of potentially toxic elements from silver smelting slag by synthetic environmental solutions.

PubMed

Ash, Christopher; Borůvka, Luboš; Tejnecký, Václav; Šebek, Ondřej; Nikodem, Antonín; Drábek, Ondřej

2013-11-15

Waste slag which is created during precious metal smelting contains high levels of potentially toxic elements (PTE) which can be mobilised from unconfined deposits into the local environment. This paper examines the extractability of selected PTE (Pb, Zn, Cd, Mn) from slag samples by synthetic solutions designed to replicate those in the environment. Extracting agents were used to replicate potential leaching scenarios which are analogous to natural chemical weathering. Slag was submersed in a rainwater simulation solution (RSS), weak citric acid solution (representing rhizosphere secretions) and control solutions (deionised water) for a one month period with solution analyses made at intervals of 1, 24, 168 and 720 h. In 1 mM citric acid, dissolution of Cd and Zn showed little change with time, although for Zn the initial dissolution was considerable. Lead in citric acid was characterized by overall poor extractability. Mn solubility increased until an equilibrium state occurred within 24 h. The solubility of studied metals in citric acid can be characterized by a short time to equilibrium. RSS proved to be an effective solvent that, unlike citric acid solution, extracted increasing concentrations of Cd, Mn and Zn with time. Solubility of Pb in RSS was again very low. When taken as a proportion of a single 2 M HNO3 extraction which was applied to slag samples, Cd was the element most readily leached into RSS and control samples. In both studied solvents, slag heterogeneity is prominent in the case of Cd and Zn solubility. Contact time with solvent appears to be an important variable for the release of PTE from slag into solution. The purpose of this study was to provide insight into the environmental chemical dissolution of PTE from slag, which causes their enrichment in surrounding soils and surface waters. Copyright © 2013 Elsevier Ltd. All rights reserved.

Speciation, Characterization, And Mobility Of As, Se and Hg In Flue Gas Desulphurization Residues

EPA Science Inventory

Flue gas from coal combustion contains significant amounts of volatile toxic trace elements such as arsenic (As), selenium (Se) and mercury (Hg). The capture of these elements in the flue gas desulphurization (FGD) scrubber unit has resulted in generation of a metal-laden residue...

Speciation, Characterization, And Mobility Of As, Se, and Hg In Flue Gas Desulphurization Residues

EPA Science Inventory

Flue gas from coal combustion contains significant amounts of volatile elements, such as arsenic (As), selenium (Se) and mercury (Hg), which could lead to serious environmental health risks. The capture of these toxic elements in the scrubber with a flue gas desulphurization (FGD...

High-resolution genome-wide scan of genes, gene-networks and cellular systems impacting the yeast ionome

USDA-ARS?s Scientific Manuscript database

To balance the demand for uptake of essential elements with their potential toxicity living cells have complex regulatory mechanisms. Here, we describe a genome-wide screen to identify genes that impact the elemental composition (‘ionome’) of yeast Saccharomyces cerevisiae. Using inductively coupled...

Toxicology of sulfur in ruminants: review

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

Kandylis, K.

1984-10-01

This review deals with the toxicology of sulfur in ruminants including toxicity, neurotoxic effects, and mechanism of toxic action of hydrogen sulfide, clinical signs, and treatment. It will report effects of excessive intake of sulfur by ruminants on feed intake, animal performance, ruminal digestion and motility, rumination, and other physiological functions. Poisoning of animals with sulfur from industrial emissions (sulfur dioxide) also is discussed. Excessive quantities of dietary sulfur (above .3 to .4%) as sulfate or elemental sulfur may cause toxic effects and in extreme cases can be fatal. The means is discussed whereby consumption of excessive amounts of sulfurmore » leads to toxic effects. 53 references, 1 table.« less

Impact of heat treatment on size, structure, and bioactivity of elemental selenium nanoparticles

PubMed Central

Zhang, Jinsong; Taylor, Ethan W; Wan, Xiaochun; Peng, Dungeng

2012-01-01

Background Elemental selenium nanoparticles have emerged as a novel selenium source with the advantage of reduced risk of selenium toxicity. The present work investigated whether heat treatment affects the size, structure, and bioactivity of selenium nanoparticles. Methods and results After a one-hour incubation of solution containing 80 nm selenium particles in a 90°C water bath, the nanoparticles aggregated into larger 110 nm particles and nanorods (290 nm × 70 nm), leading to significantly reduced bioavailability and phase II enzyme induction in selenium-deficient mice. When a solution containing 40 nm selenium nanoparticles was treated under the same conditions, the nanoparticles aggregated into larger 72 nm particles but did not transform into nanorods, demonstrating that the thermostability of selenium nanoparticles is size-dependent, smaller selenium nanoparticles being more resistant than larger selenium nanoparticles to transformation into nanorods during heat treatment. Conclusion The present results suggest that temperature and duration of the heat process, as well as the original nanoparticle size, should be carefully selected when a solution containing selenium nanoparticles is added to functional foods. PMID:22359458

Emergence of the Epidemic Methicillin-Resistant Staphylococcus aureus Strain USA300 Coincides with Horizontal Transfer of the Arginine Catabolic Mobile Element and speG-mediated Adaptations for Survival on Skin

PubMed Central

Planet, Paul J.; LaRussa, Samuel J.; Dana, Ali; Smith, Hannah; Xu, Amy; Ryan, Chanelle; Uhlemann, Anne-Catrin; Boundy, Sam; Goldberg, Julia; Narechania, Apurva; Kulkarni, Ritwij; Ratner, Adam J.; Geoghegan, Joan A.; Kolokotronis, Sergios-Orestis; Prince, Alice

2013-01-01

ABSTRACT The arginine catabolic mobile element (ACME) is the largest genomic region distinguishing epidemic USA300 strains of methicillin-resistant Staphylococcus aureus (MRSA) from other S. aureus strains. However, the functional relevance of ACME to infection and disease has remained unclear. Using phylogenetic analysis, we have shown that the modular segments of ACME were assembled into a single genetic locus in Staphylococcus epidermidis and then horizontally transferred to the common ancestor of USA300 strains in an extremely recent event. Acquisition of one ACME gene, speG, allowed USA300 strains to withstand levels of polyamines (e.g., spermidine) produced in skin that are toxic to other closely related S. aureus strains. speG-mediated polyamine tolerance also enhanced biofilm formation, adherence to fibrinogen/fibronectin, and resistance to antibiotic and keratinocyte-mediated killing. We suggest that these properties gave USA300 a major selective advantage during skin infection and colonization, contributing to the extraordinary evolutionary success of this clone. PMID:24345744

Elemental selenium particles at nano-size (Nano-Se) are more toxic to Medaka (Oryzias latipes) as a consequence of hyper-accumulation of selenium: a comparison with sodium selenite.

PubMed

Li, Hongcheng; Zhang, Jinsong; Wang, Thanh; Luo, Wenru; Zhou, Qunfang; Jiang, Guibin

2008-09-29

Recent studies have shown that elemental selenium particles at nano-size (Nano-Se) exhibited comparable bioavailability and less toxicity in mice and rats when compared to sodium selenite, selenomethinine and methylselenocysteine. However, little is known about the toxicity profile of Nano-Se in aquatic animals. In the present study, toxicities of Nano-Se and selenite in selenium-sufficient Medaka fish were compared. Selenium bioaccumulation and subsequent clearance in fish livers, gills, muscles and whole bodies were examined after 10 days of exposure to Nano-Se and selenite (100 microg Se/L) and again after 7 days of depuration. Both forms of selenium exposure effectively increased selenium concentrations in the investigated tissues. Surprisingly, Nano-Se was found to be more hyper-accumulated in the liver compared to selenite with differences as high as sixfold. Selenium clearance of both Nano-Se and selenite occurred at similar ratios in whole bodies and muscles but was not rapidly cleared from livers and gills. Nano-Se exhibited strong toxicity for Medaka with an approximately fivefold difference in terms of LC(50) compared to selenite. Nano-Se also caused larger effects on oxidative stress, most likely due to more hyper-accumulation of selenium in liver. The present study suggests that toxicity of nanoparticles can largely vary between different species and concludes that the evaluation of nanotoxicology should be carried out on a case-by-case basis.

Migration of 18 trace elements from ceramic food contact material: influence of pigment, pH, nature of acid and temperature.

PubMed

Demont, M; Boutakhrit, K; Fekete, V; Bolle, F; Van Loco, J

2012-03-01

The effect of pH, nature of acid and temperature on trace element migration from ceramic ware treated with 18 commercially available glazes was studied. Besides of the well-studied lead and cadmium, migration of other toxic and non toxic elements such as aluminum, boron, barium, cobalt, chrome, copper, iron, lithium, magnesium, manganese, nickel, antimony, tin, strontium, titanium, vanadium, zinc and zirconium was investigated in order to evaluate their potential health hazards. Trace element concentrations were determined with Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). This study suggests that there is indeed a health risk concerning the possible migration of other elements than lead and cadmium. At low pH (2

Body burden of toxic metals and rare earth elements in non-smokers, cigarette smokers and electronic cigarette users.

PubMed

Badea, Mihaela; Luzardo, Octavio P; González-Antuña, Ana; Zumbado, Manuel; Rogozea, Liliana; Floroian, Laura; Alexandrescu, Dana; Moga, Marius; Gaman, Laura; Radoi, Mariana; Boada, Luis D; Henríquez-Hernández, Luis Alberto

2018-06-13

Smoking is considered an important source for inorganic elements, most of them toxic for human health. During the last years, there has been a significant increase in the use of e-cigarettes, although the role of them as source of inorganic elements has not been well established. A cross-sectional study including a total of 150 subjects from Brasov (Romania), divided into three groups (non-smokers, cigarette smokers and electronic cigarettes smokers) were recruited to disclose the role of smoking on the human exposure to inorganic elements. Concentration of 42 elements, including trace elements, elements in the ATSDR's priority pollutant list and rare earth elements (REE) were measured by ICP-MS in the blood serum of participants. Cigarette smokers showed the highest levels of copper, molybdenum, zinc, antimony, and strontium. Electronic cigarette (e-cigarette) users presented the highest concentrations of selenium, silver, and vanadium. Beryllium, europium and lanthanides were detected more frequently among e-cigarette users (20.6%, 23.5%, and 14.7%) than in cigarette smokers (1.7%, 19.0%, and 12.1%, respectively); and the number of detected REE was also higher among e-cigarette users (11.8% of them showed more than 10 different elements). Serum levels of cerium and erbium increased as the duration of the use of e-cigarettes was longer. We have found that smoking is mainly a source of heavy metals while the use of e-cigarettes is a potential source of REE. However, these elements were detected at low concentrations. Copyright © 2018 Elsevier Inc. All rights reserved.

Toxicity of selected insecticides and insecticide mixtures to adult brown stink bug (Heteroptera: Pentatomidae)

USDA-ARS?s Scientific Manuscript database

Glass vial bioassay were conducted to evaluate the toxicity of selected insecticides and insecticide mixtures to the brown stink bug (BSB), Euschistus servus (Say) collected from blacklight traps, cotton plants and weeds in farming areas in the Brazos Valley of Texas. Dicrotophos was 5- and 18-fold...

RELATIONSHIPS OF QUANTITATIVE STRUCTURE-ACTIVITY TO COMPARATIVE TOXICITY OF SELECTED PHENOLS IN THE 'PIMEPHALES PROMELAS' AND 'TETRAHYMENA PYRIFORMIS' TEST SYSTEMS

EPA Science Inventory

The relative toxic response of 27 selected phenols in the 96-hr acute flowthrough Pimephales promelas (fathead minnow) and the 48- to 60-hr chronic static Tetrahymena pyriformis (ciliate protozoan) test systems was evaluated. Log Kow-dependent linear regression analyses revealed ...

HAIR HEAVY METAL AND ESSENTIAL TRACE ELEMENT CONCENTRATION IN CHILDREN WITH AUTISM SPECTRUM DISORDER.

PubMed

Tabatadze, T; Zhorzholiani, L; Kherkheulidze, M; Kandelaki, E; Ivanashvili, T

2015-11-01

Our study aims evaluation of level of essential trace elements and heavy metals in the hair samples of children with autistic spectrum disorder (ASD) and identification of changes that are associated with autistic spectrum disorders. Case-control study was conducted at Child Development Center of Iashvili Children's Central Hospital (LD).We studied 60 children aged from 4 to 5 years old. The concentrations of 28 elements among (Ca,Zn, K, Fe, Cu, Se, Mn, Cr, S, Br, Cl, Co, Ag, V, Ni, Rb, Mo, Sr, Ti, Ba, Pb, As, Hg, Cd, Sb, Zr, Sn, Bi) them trace elements and toxic metals) were determined in scalp hair samples of children (n=30) with autistic spectrum disorder (ASD) and from control group of healthy children (n=30) with matched sex and age. Micro-elemental status was detected in the hair, with roentgen-fluorescence spectrometer method (Method MBИ 081/12-4502-000, Apparatus ALVAX- CIP, USA - UKRAIN) .To achieve the similarity of study and control groups, pre and postnatal as well as family and social history were assessed and similar groups were selected. Children with genetic problems, malnourished children, children from families with social problems were excluded from the study. The diagnosis of ASD were performed by pediatrician and psychologist (using M-CHAT and ADOS) according to DSM IV (Diagnostic and Statistical Manual of Mental Disorders from the American Psychiatric association) criteria. The study was statistically analyzed using computer program SPSS 19. Deficiencies of essential trace microelements revealed in both group, but there was significant difference between control and studied groups. The most deficient element was zinc (92% in target and 20% in control), then - manganese (55% and 8%) and selenium (38% and 4%). In case of cooper study revealed excess concentration of this element only in target group in 50% of cases. The contaminations to heavy metals were detected in case of lead (78% and 16), mercury (43% and 10%) and cadmium (38% and 8%). The study statistical results indicated, that deficient concentrations of trace elements such as zinc, manganese, molybdenum and selenium in hair significantly linked with ASD (Kramer's V was 0,740; 0,537; 0,333; 0,417 accordingly). In case of cooper we got excess levels of this element and this data was highly linked with autism spectrum disorder. We got high associations and significant values between of lead, mercury and cadmium concentrations and ASD. Study results indicate that there are significant differences of hair essential trace elements concentrations in children with autism spectrum disorder comparing with healthy children group. The result obtained also showed high contamination to heavy metals such as lead, mercury and cadmium in ASD children compared to healthy ones. So, our study demonstrated alteration in levels of toxic heavy metals and essential trace elements in children with autistic spectrum disorders as compared to healthy children. This suggests a possible pathophysiological role of heavy metals and trace elements in the genesis of symptoms of autism spectrum disorders.

Trace and major element levels in rats after oral administration of diesel and biodiesel derived from opium poppy (Papaver somniferum L.) seeds.

PubMed

Aksoy, Laçine; Sözbilir, Nalan Bayşu

2015-10-01

The study investigated the toxic effects of diesel and biodiesel derived from opium poppy (Papaver somniferum L.) oil seeds on the trace and major elements in kidney, lung, liver, and serum of rats. By the end of 21 days, trace and major element concentrations in kidney, lung, and liver tissues and the serum were measured using inductively coupled plasma-optical emission spectroscopy. We observed that trace and major element levels in kidney, lung, and liver tissues and the serum changed. Especially, important differences were detected in trace and major element concentrations in kidney and lung tissues. In kidney tissue, the concentration differences of calcium, sodium, and zinc (Zn) were found between diesel and biodiesel groups. In lung tissue, the concentration differences of cadmium, lithium, magnesium, manganese, and Zn were found between diesel and biodiesel groups. Among the significant findings, Zn concentration in serum and liver tissue of diesel and biodiesel were different from control (p < 0.05). However, the metal levels of biodiesel group were similar to control group. Due to lesser toxicity of biodiesel, it could be considered as an alternate fuel. © The Author(s) 2013.

Determination of trace elements in bovine semen samples by inductively coupled plasma mass spectrometry and data mining techniques for identification of bovine class.

PubMed

Aguiar, G F M; Batista, B L; Rodrigues, J L; Silva, L R S; Campiglia, A D; Barbosa, R M; Barbosa, F

2012-12-01

The reproductive performance of cattle may be influenced by several factors, but mineral imbalances are crucial in terms of direct effects on reproduction. Several studies have shown that elements such as calcium, copper, iron, magnesium, selenium, and zinc are essential for reproduction and can prevent oxidative stress. However, toxic elements such as lead, nickel, and arsenic can have adverse effects on reproduction. In this paper, we applied a simple and fast method of multi-element analysis to bovine semen samples from Zebu and European classes used in reproduction programs and artificial insemination. Samples were analyzed by inductively coupled plasma spectrometry (ICP-MS) using aqueous medium calibration and the samples were diluted in a proportion of 1:50 in a solution containing 0.01% (vol/vol) Triton X-100 and 0.5% (vol/vol) nitric acid. Rhodium, iridium, and yttrium were used as the internal standards for ICP-MS analysis. To develop a reliable method of tracing the class of bovine semen, we used data mining techniques that make it possible to classify unknown samples after checking the differentiation of known-class samples. Based on the determination of 15 elements in 41 samples of bovine semen, 3 machine-learning tools for classification were applied to determine cattle class. Our results demonstrate the potential of support vector machine (SVM), multilayer perceptron (MLP), and random forest (RF) chemometric tools to identify cattle class. Moreover, the selection tools made it possible to reduce the number of chemical elements needed from 15 to just 8. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A multi-element screening method to identify metal targets for blood biomonitoring in green sea turtles (Chelonia mydas).

PubMed

Villa, C A; Finlayson, S; Limpus, C; Gaus, C

2015-04-15

Biomonitoring of blood is commonly used to identify and quantify occupational or environmental exposure to chemical contaminants. Increasingly, this technique has been applied to wildlife contaminant monitoring, including for green turtles, allowing for the non-lethal evaluation of chemical exposure in their nearshore environment. The sources, composition, bioavailability and toxicity of metals in the marine environment are, however, often unknown and influenced by numerous biotic and abiotic factors. These factors can vary considerably across time and space making the selection of the most informative elements for biomonitoring challenging. This study aimed to validate an ICP-MS multi-element screening method for green turtle blood in order to identify and facilitate prioritisation of target metals for subsequent fully quantitative analysis. Multi-element screening provided semiquantitative results for 70 elements, 28 of which were also determined through fully quantitative analysis. Of the 28 comparable elements, 23 of the semiquantitative results had an accuracy between 67% and 112% relative to the fully quantified values. In lieu of any available turtle certified reference materials (CRMs), we evaluated the use of human blood CRMs as a matrix surrogate for quality control, and compared two commonly used sample preparation methods for matrix related effects. The results demonstrate that human blood provides an appropriate matrix for use as a quality control material in the fully quantitative analysis of metals in turtle blood. An example for the application of this screening method is provided by comparing screening results from blood of green turtles foraging in an urban and rural region in Queensland, Australia. Potential targets for future metal biomonitoring in these regions were identified by this approach. Copyright © 2014 Elsevier B.V. All rights reserved.

Trace element partitioning behavior of coal gangue-fired CFB plant: experimental and equilibrium calculation.

PubMed

Zhang, Yingyi; Nakano, Jinichiro; Liu, Lili; Wang, Xidong; Zhang, Zuotai

2015-10-01

Energy recovery is a promising method for coal gangue utilization, during which the prevention of secondary pollution, especially toxic metal emission, is a significant issue in the development of coal gangue utilization. In the present study, investigation into trace element partitioning behavior from a coal gangue-fired power plant in Shanxi province, China, has been conducted. Besides the experimental analysis, thermodynamic equilibrium calculation was also conducted to help the further understanding on the effect of different parameters. Results showed that Hg, As, Be, and Cd were highly volatile elements in the combustion of coal gangue, which were notably enriched in fly ash and may be emitted into the environment via the gas phase. Cr and Mn were mostly non-volatile and were enriched in the bottom ash. Pb, Co, Zn, Cu, and Ni were semi-volatile elements and were enriched in the fly ash to varying degrees. Equilibrium calculations show that the air/fuel ratio and the presence of Cl highly affect the element volatility. The presence of mineral phases, such as aluminosilicates, depresses the volatility of elements by chemical immobilization and competition in Cl. The coal gangue, fly ash, and bottom ash all passed the toxicity characteristic leaching procedure (TCLP), and their alkalinity buffers the acidity of the solution and contributes to the low solubility of the trace elements.

Determination of essential and toxic elements in Cordyceps kyushuensis Kawam by inductively coupled plasma mass spectrometry.

PubMed

Zhang, Guoying; Zhao, Yanxin; Liu, Fengjun; Ling, Jianya; Lin, Jianqiang; Zhang, Changkai

2013-01-01

In this study, a total of 20 elements (essential, non-essential and toxic): lithium (Li), sodium (Na), potassium (K), gallium (Ga), magnesium (Mg), zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), vanadium (V), chromium (Cr), nickel (Ni), cobalt (Co), molybdenum (Mo), selenium (Se), barium (Ba), tin (Sn), arsenic (As), lead (Pb) cadmium (Cd) and mercury (Hg) in natural and cultured Cordyceps kyushuensis have been determined by means of inductively coupled plasma mass spectrometry (ICP-MS). Cultured stroma, natural stroma and natural worm were digested by microwave-assisted method before analysis. The proposed ICP-MS method was validated by analyzing a certified reference material (CRM) GBW10015 (spinach). The results of one-way analysis of variance (ANOVA) revealed that the element concentrations in the three kinds of samples were significantly different (p<0.05). Except for Mg, Zn, Cu, the values of other elemental contents were the highest in the stroma of natural C. kyushuensis. In comparison with the worm, the concentrations of determined elements in wild stroma were higher. The remarkable difference of elemental contents between cultured and natural stroma may be caused by distinct growing environment. This finding highlighted the usefulness of ICP-MS elemental analysis and enhanced the value of C. kyushuensis as a candidate for nourishing food based on its composition. Copyright © 2012 Elsevier B.V. All rights reserved.

Review of the Toxicity of the Metallic Compounds Proposed for Use in the New Green Missile Formulation

NASA Technical Reports Server (NTRS)

Major, Michael A.

2000-01-01

In an effort to modernize and minimize hazards posed by the toxic components of missile propellant, the USACHPPM has been tasked to provide a comparison of the toxicity of compounds currently in use as missile propellants and the suite of compounds proposed to replace them. This report deals with the portion of this work concerning the toxicity of the organometallic compounds used in these formulations. Toxicity assessments of the organic compounds used in these formulations are published elsewhere. In general, toxicity data were available for all the metal compounds of concern or for closely related compounds that can serve as surrogates for the assessment of toxicity. We have high confidence in the reliability of these comparisons. This report is organized by element to provide the reader with an in-depth assessment with a minimum of redundancy. The narrative will first describe general concepts about the toxicity of each metal and then provide a summary of the toxicological information available for the specific compound.

Recent developments in human biomonitoring: non-invasive assessment of target tissue dose and effects of pneumotoxic metals.

PubMed

Mutti, A; Corradi, M

2006-01-01

Tobacco smoke and polluted environments substantially increase the lung burden of pneumotoxic chemicals, particularly pneumotoxic metallic elements. To achieve a better understanding of the early events between exposure to inhaled toxicants and the onset of adverse effects on the lung, the characterization of dose at the target organ would be extremely useful. Exhaled breath condensate (EBC), obtained by cooling exhaled air under conditions of spontaneous breathing, is a novel technique that could provide a non-invasive assessment of pulmonary pathobiology. Considering that EBC is water practically free of interfering solutes, it represents an ideal biological matrix for elemental characterization. Published data show that several toxic metals and trace elements are detectable in EBC, raising the possibility of using this medium to quantify the lung tissue dose of pneumotoxic substances. This novel approach may represent a significant advance over the analysis of alternative media (blood, serum, urine, hair), which are not as reliable (owing to interfering substances in the complex matrix) and reflect systemic rather than lung (target tissue) levels of both toxic metals and essential trace elements. Data obtained among workers occupationally exposed to either hard metals or chromium (VI) and in smokers with or without chronic obstructive pulmonary disease (COPD) are reviewed to show that--together with biomarkers of exposure--EBC also allows the simultaneous quantification of biomarkers of effect directly sampled from the epithelial lining fluid, thus providing novel insights on both kinetic and dynamic aspects of metal toxicology.

Biomonitoring of environmental pollution using growth tree rings of Tipuana tipu: Quantification by synchrotron radiation total reflection X-ray fluorescence

NASA Astrophysics Data System (ADS)

Geraldo, S. M.; Canteras, F. B.; Moreira, S.

2014-02-01

Currently, many studies use the bioindicators to qualitatively and/or quantitatively measure pollution. The analyses of tree growth rings represent one such bioindicator as changes in the environment are often recorded as impressions in the wood. The main objective of the present study is to examine the growth rings of Tipuana tipu - a member of the Leguminosae family that is native to Argentina and Bolivia and was introduced in Brazil as an ornamental plant - for potentially toxic elements. T. tipu is one of the most common trees in the urban landscape of Sao Paulo city and would provide an accurate reflection of environment changes. Tree ring samples previously dated using Synchrotron Radiation Total Reflection X-ray Fluorescence were collected from strategic locations in Sao Paulo. These locations include Piracicaba (SP) that has little access and small flow traffic and the campus of the University of São Paulo. Some trace elements present concentrations higher than considered as normal in some periods. In São Paulo city, samples collected from the campus of University of São Paulo (Butantã), showed the highest toxicity, with concentrations above the tolerable limit for the elements: Cr, Cu, and Pb. For the samples collected in Piracicaba city, one sample presented highest concentrations for the majority of the elements when compared to the other four samples collected at the same place, exceeding the toxicity limits for: Cr, Ni, Cu, and Pb.

Elemental mercury neurotoxicity and clinical recovery of function: A review of findings, and implications for occupational health.

PubMed

Calabrese, Edward J; Iavicoli, Ivo; Calabrese, Vittorio; Cory-Slechta, Deborah A; Giordano, James

2018-05-01

This paper assessed approximately 30 studies, mostly involving occupationally exposed subjects, concerning the extent to which those who developed elemental mercury (Hg)-induced central and/or peripheral neurotoxicities from chronic or acute exposures recover functionality and/or performance. While some recovery occurred in the vast majority of cases, the extent of such recoveries varied considerably by individual and endpoint. Factors accounting for the extensive inter-individual variation in toxicity and recovery were not specifically assessed such as age, gender, diet, environmental enrichment, chelation strategies and dose-rate. While the data indicate that psychomotor endpoints often show substantial and relatively rapid (i.e., 2-6 months) recovery and that neuropsychological endpoints display slower and less complete recovery, generalizations are difficult due to highly variable study designs, use of different endpoints measured between studies, different Hg exposures based on blood/urine concentrations and Hg dose-rates, the poor capacity for replicating findings due to the unpredictable/episodic nature of harmful exposures to elemental Hg, and the inconsistency of the initiation of studies after induced toxicities and the differing periods of follow up during recovery periods. Finally, there is strikingly limited animal model literature on the topic of recovery/reversibility of elemental Hg toxicity, a factor which significantly contributes to the overall marked uncertainties for predicting the rate and magnitude of recovery and the factors that affect it. Copyright © 2018 Elsevier Inc. All rights reserved.

Synthesis, characterization and applications of a new cation exchanger tamarind sulphonic acid (TSA) resin.

PubMed

Singh, A V; Sharma, Naresh Kumar; Rathore, Abhay S

2012-01-01

A new composite cation exchanger, tamarind sulphonic acid (TSA) resin has been synthesized. The chemically modified TSA ion exchange resin has been used for the removal and preconcentration of Zn2+, Cd2+, Fe2+, Co2+ and Cu2+ ions in aqueous solution and effluent from the Laxmi steel plant in Jodhpur, India. This type of composite represents a new class of hybrid ion exchangers with good ion exchange capacity, stability, reproducibility and selectivity for toxic metal ions found in effluent from the steel industry. The characterization of the resin was carried out by determining the ion-exchange capacity, elemental analysis, pH titration, Fourier transform infrared spectra and thermal analysis. The distribution coefficients (K(d)) of toxic metal ions were determined in a reference aqueous solution and the steel plant effluent at different pH values; the absorbency of different metal ions on the TSA resin was studied for up to 10 cycles. The adsorption of different metal ions on TSA resin follows the order: Co2+ > Cu2+ > Zn2+ > Fe2+ > Cd2+. The ion exchange capacity of TSA resin is 2.87%.

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

Belinsky, S. A.; Hoover, M. D.; Bradley, P. L.

This document from the Inhalation Toxicology Research Institute includes annual reports in the following general areas: (I) Aerosol Technology and Characterization of Airborne Materials; (II) Deposition, transport, and clearance of inhaled Toxicants; (III) Metabolism and Markers of Inhaled Toxicants; (IV) Carcinogenic Responses to Toxicants; (V) Mechanisms of carcinogenic response to Toxicants; (VI) Non carcinogenic responses to inhaled toxicants; (VII) Mechanisms of noncarcinogenic Responses to Inhaled Toxicants; (VIII) The application of Mathematical Modeling to Risk Estimates. 9 appendices are also included. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

Cadmium Handling, Toxicity and Molecular Targets Involved during Pregnancy: Lessons from Experimental Models.

PubMed

Jacobo-Estrada, Tania; Santoyo-Sánchez, Mitzi; Thévenod, Frank; Barbier, Olivier

2017-07-22

Even decades after the discovery of Cadmium (Cd) toxicity, research on this heavy metal is still a hot topic in scientific literature: as we wrote this review, more than 1440 scientific articles had been published and listed by the PubMed.gov website during 2017. Cadmium is one of the most common and harmful heavy metals present in our environment. Since pregnancy is a very particular physiological condition that could impact and modify essential pathways involved in the handling of Cd, the prenatal life is a critical stage for exposure to this non-essential element. To give the reader an overview of the possible mechanisms involved in the multiple organ toxic effects in fetuses after the exposure to Cd during pregnancy, we decided to compile some of the most relevant experimental studies performed in experimental models and to summarize the advances in this field such as the Cd distribution and the factors that could alter it (diet, binding-proteins and membrane transporters), the Cd-induced toxicity in dams (preeclampsia, fertility, kidney injury, alteration in essential element homeostasis and bone mineralization), in placenta and in fetus (teratogenicity, central nervous system, liver and kidney).

Arsenic-transforming microbes and their role in biomining processes.

PubMed

Drewniak, L; Sklodowska, A

2013-11-01

It is well known that microorganisms can dissolve different minerals and use them as sources of nutrients and energy. The majority of rock minerals are rich in vital elements (e.g., P, Fe, S, Mg and Mo), but some may also contain toxic metals or metalloids, like arsenic. The toxicity of arsenic is disclosed after the dissolution of the mineral, which raises two important questions: (1) why do microorganisms dissolve arsenic-bearing minerals and release this metal into the environment in a toxic (also for themselves) form, and (2) How do these microorganisms cope with this toxic element? In this review, we summarize current knowledge about arsenic-transforming microbes and their role in biomining processes. Special consideration is given to studies that have increased our understanding of how microbial activities are linked to the biogeochemistry of arsenic, by examining (1) where and in which forms arsenic occurs in the mining environment, (2) microbial activity in the context of arsenic mineral dissolution and the mechanisms of arsenic resistance, (3) the minerals used and technologies applied in the biomining of arsenic, and (4) how microbes can be used to clean up post-mining environments.

Cadmium Handling, Toxicity and Molecular Targets Involved during Pregnancy: Lessons from Experimental Models

PubMed Central

Santoyo-Sánchez, Mitzi; Thévenod, Frank; Barbier, Olivier

2017-01-01

Even decades after the discovery of Cadmium (Cd) toxicity, research on this heavy metal is still a hot topic in scientific literature: as we wrote this review, more than 1440 scientific articles had been published and listed by the PubMed.gov website during 2017. Cadmium is one of the most common and harmful heavy metals present in our environment. Since pregnancy is a very particular physiological condition that could impact and modify essential pathways involved in the handling of Cd, the prenatal life is a critical stage for exposure to this non-essential element. To give the reader an overview of the possible mechanisms involved in the multiple organ toxic effects in fetuses after the exposure to Cd during pregnancy, we decided to compile some of the most relevant experimental studies performed in experimental models and to summarize the advances in this field such as the Cd distribution and the factors that could alter it (diet, binding-proteins and membrane transporters), the Cd-induced toxicity in dams (preeclampsia, fertility, kidney injury, alteration in essential element homeostasis and bone mineralization), in placenta and in fetus (teratogenicity, central nervous system, liver and kidney). PMID:28737682

Toxicity and bioavailability of metals in the Missouri River adjacent to a lead refinery

USGS Publications Warehouse

Chapman, Duane C.; Allert, Ann L.; Fairchild, James F.; May, Thomas W.; Schmitt, Christopher J.; Callahan, Edward V.

2001-01-01

This study is an evaluation of the potential environmental impacts of contaminated groundwater from the ASARCO metals refining facility adjacent to the Missouri River in Omaha, Nebraska. Surface waters, sediments, and sediment pore waters were collected from the Burt-Izard drain, which transects the facility, and from the Missouri River adjacent to the facility. Groundwater was also collected from the facility. Waters and sediments were analyzed for inorganic contaminants, and the toxicity of the waters was evaluated with the Ceriodaphnia dubia 7-day test. Concentrations of several elemental contaminants were highly elevated in the groundwater, but not in river sediment pore waters. Lead concentrations were moderately elevated in whole sediment at one site, but lead concentrations in pore waters were low due to apparent sequestration by acid-volatile sulfides. The groundwater sample was highly toxic to C. dubia, causing 100% mortality. Even at the lowest groundwater concentration tested (6.25%) C. dubia survival was reduced; however, at that concentration, reproduction was not significantly different from upstream porewater reference samples. Sediment pore waters were not toxic, except reproduction in pore water collected from one downstream site was somewhat reduced. The decrease in reproduction could not be attributed to measured elemental contaminants.

Areal distribution and concentration of contaminants of concern in surficial streambed and lakebed sediments, Lake St. Clair and tributaries, Michigan, 1990-2003

USGS Publications Warehouse

Rachol, Cynthia M.; Button, Daniel T.

2006-01-01

As part of the Lake St. Clair Regional Monitoring Project, the U.S. Geological Survey evaluated data collected from surficial streambed and lakebed sediments in the Lake Erie-Lake St. Clair drainages. This study incorporates data collected from 1990 through 2003 and focuses primarily on the U.S. part of the Lake St. Clair Basin, including Lake St. Clair, the St. Clair River, and tributaries to Lake St. Clair. Comparable data from the Canadian part of the study area are included where available. The data are compiled into 4 chemical classes and consist of 21 compounds. The data are compared to effects-based sediment-quality guidelines, where the Threshold Effect Level and Lowest Effect Level represent concentrations below which adverse effects on biota are not expected and the Probable Effect Level and Severe Effect Level represent concentrations above which adverse effects on biota are expected to be frequent.Maps in the report show the spatial distribution of the sampling locations and illustrate the concentrations relative to the selected sediment-quality guidelines. These maps indicate that sediment samples from certain areas routinely had contaminant concentrations greater than the Threshold Effect Concentration or Lowest Effect Level. These locations are the upper reach of the St. Clair River, the main stem and mouth of the Clinton River, Big Beaver Creek, Red Run, and Paint Creek. Maps also indicated areas that routinely contained sediment contaminant concentrations that were greater than the Probable Effect Concentration or Severe Effect Level. These locations include the upper reach of the St. Clair River, the main stem and mouth of the Clinton River, Red Run, within direct tributaries along Lake St. Clair and in marinas within the lake, and within the Clinton River headwaters in Oakland County.Although most samples collected within Lake St. Clair were from sites adjacent to the mouths of its tributaries, samples analyzed for trace-element concentrations were collected throughout the lake. The distribution of trace-element concentrations corresponded well with the results of a two-dimensional hydrodynamic model of flow patterns from the Clinton River into Lake St. Clair. The model was developed independent from the bed sediment analysis described in this report; yet it showed a zone of deposition for outflow from the Clinton River into Lake St. Clair that corresponded well with the spatial distribution of trace-element concentrations. This zone runs along the western shoreline of Lake St. Clair from L'Anse Creuse Bay to St. Clair Shores, Michigan and is reflected in the samples analyzed for mercury and cadmium.Statistical summaries of the concentration data are presented for most contaminants, and selected statistics are compared to effects-based sediment-quality guidelines. Summaries were not computed for dieldrin, chlordane, hexachlorocyclohexane, lindane, and mirex because insufficient data are available for these contaminants. A statistical comparison showed that the median concentration for hexachlorobenzene, anthracene, benz[a]anthracene, chrysene, and pyrene are greater than the Threshold Effect Concentration or Lowest Effect Level.Probable Effect Concentration Quotients provide a mechanism for comparing the concentrations of contaminant mixtures against effects-based biota data. Probable Effect Concentration Quotients were calculated for individual samples and compared to effects-based toxicity ranges. The toxicity-range categories used in this study were nontoxic (quotients < 0.5) and toxic (quotients > 0.5). Of the 546 individual samples for which Probable Effect Concentration Quotients were calculated, 469 (86 percent) were categorized as being nontoxic and 77 (14 percent) were categorized as being toxic. Bed-sediment samples with toxic Probable Effect Concentration Quotients were collected from Paint Creek, Galloway Creek, the main stem of the Clinton River, Big Beaver Creek, Red Run, Clinton River towards the mouth, Lake St. Clair along the western shore, and the St. Clair River near Sarnia.

Field screening of water quality, bottom sediment, and biota associated with irrigation drainage in and near Walker River Indian Reservation, Nevada 1994-95

USGS Publications Warehouse

Thodal, Carl E.; Tuttle, Peter L.

1996-01-01

A study was begun in 1994 to determine whether the quality of irrigation drainage from the Walker River Indian Reservation, Nevada, has caused or has potential to cause harmful effects on human health or on fish and wildlife, or may adversely affect the suitability of the Walker River for other beneficial uses. Samples of water, bottom sediment, and biota were collected during June-August 1994 (during a drought year) from sites upstream from and on the Walker River Indian Reservation for analyses of trace elements. Other analyses included physical characteristics, major dissolved constituents, selected species of water-soluble nitrogen and phosphorus, and selected pesticides in bottom sediment. Water samples were collected again from four sites on the Reservation in August 1995 (during a wetterthan- average year) to provide data for comparing extreme climatic conditions. Water samples collected from the Walker River Indian Reservation in 1994 equaled or exceeded the Nevada water-quality standard or level of concern for at least one of the following: water temperature, pH, dissolved solids, unionized ammonia, phosphate, arsenic, boron, chromium, lead, and molybdenum; in 1995, only a single sample from one site exceeded a Nevada water-quality standard for molybdenum. Levels of concern for trace elements in bottom sediment collected in 1994 were equaled or exceeded for arsenic, iron, manganese, and zinc. Concentrations of organochiorine pesticide residues in bottom sediment were below analytical reporting limits. Levels of concern for trace-elements in samples of biota were equaled or exceeded for arsenic, boron, copper, and mercury. Results of toxicity testing indicate that only water samples from Walker Lake caused a toxic response in test bacteria. Arsenic and boron concentrations in water, bottom sediment, and biological tissue exceeded levels of concern throughout the Walker River Basin, but most commonly in the lower Walker River Basin. Mercury also was elevated in several biological samples collected throughout the Basin, although concentrations in water and bottom sediment were below analytical reporting limits. Sources of arsenic, boron, and mercury in the Basin are uncertain, but ambient levels reported for a variety of sample matrices collected from western Nevada generally exceed ranges cited as natural background levels. Because these potentially toxic constituents exceeded concern levels in areas that do not directly receive irrigation drainage, concentrations measured in samples collected for this study may not necessarily be attributable to agricultural activities. Diversion of river water for irrigation may have greater effects on beneficial uses of water and on fish and wildlife than does drainage from agricultural areas on the Reservation. In 1994, agricultural water consumption precluded dilution of ground-water seepage to the river channel. This resulted in concentrations of potentially toxic solutes that exceeded levels of concern. Diversion of irrigation water also may have facilitated leaching of potentially toxic solutes from irrigated soil on the Reservation, but during this study all water applied for irrigation on the Reservation was either consumed by evapotranspiration or infiltrated to recharge shallow ground water. No irrigation drainage was found on the Reservation during this study. However, because 1994 samples of ground-water seepage to the Walker River channel exceeded at least six Nevada waterquality standards, water-quality problems may result should ground-water levels rise enough to cause ground-water discharge to the agricultural drain on the Reservation. Nevertheless, the potential for adverse effects from irrigation drainage on the Reservation is believed to be small because surface-water rights for the Walker River Indian Reservation amount to only 2 percent of total surface- water rights in the entire Walker River Basin.

Toxic trace element assessment for soils/sediments deposited during Hurricanes Katrina and Rita from southern Louisiana, USA: a sequential extraction analysis.

PubMed

Shi, Honglan; Witt, Emitt C; Shu, Shi; Su, Tingzhi; Wang, Jianmin; Adams, Craig

2010-07-01

Analysis of soil/sediment samples collected in the southern Louisiana, USA, region three weeks after Hurricanes Katrina and Rita passed was performed using sequential extraction procedures to determine the origin, mode of occurrence, biological availability, mobilization, and transport of trace elements in the environment. Five fractions: exchangeable, bound to carbonates, bound to iron (Fe)-manganese (Mn) oxides, bound to organic matter, and residual, were subsequently extracted. The toxic trace elements Pb, As, V, Cr, Cu, and Cd were analyzed in each fraction, together with Fe in 51 soil/sediment samples. Results indicated that Pb and As were at relatively high concentrations in many of the soil/sediment samples. Because the forms in which Pb and As are present tend to be highly mobile under naturally occurring environmental conditions, these two compounds pose an increased health concern.Vanadium and Cr were mostly associated with the crystal line nonmobile residual fraction. A large portion of the Cu was associated with organic matter and residual fraction. Cadmium concentrations were low in all soil/sediment samples analyzed and most of this element tended to be associated with the mobile fractions. An average of 21% of the Fe was found in the Fe-Mn oxide fraction, indicating that a substantial part of the Fe was in an oxidized form. The significance of the overall finding of the present study indicated that the high concentrations and high availabilities of the potentially toxic trace elements As and Pb may impact the environment and human health in southern Louisiana and, in particular, the New Orleans area. Copyright (c) 2010 SETAC.

Multiple Elemental Exposures Amongst Workers at the Agbogbloshie Electronic Waste (E-Waste) Site in Ghana

PubMed Central

Srigboh, Roland Kofi; Basu, Niladri; Stephens, Judith; Asampong, Emmanuel; Perkins, Marie; Neitzel, Richard L.; Fobil, Julius

2016-01-01

Electronic waste (e-waste) recycling is growing worldwide and raising a number of environmental health concerns. One of the largest e-waste sites is Agbogbloshie (Ghana). While several toxic elements have been reported in Agbogbloshie’s environment, there is limited knowledge of human exposures there. The objectives of this study were to characterize exposures to several essential (copper, iron, manganese, selenium, zinc) and toxic (arsenic, cadmium, cobalt, chromium, mercury, nickel, lead) elements in the urine and blood of male workers (n=58) at Agbogbloshie, as well as females (n=11) working in activities that serve the site, and to relate these exposures to sociodemographic and occupational characteristics. The median number of years worked at the site was 5, and the average worker indicated being active in 6.8 tasks (of 9 key e-waste job categories). Additionally, we categorized four main e-waste activities (in brackets % of population self-reported main activity): dealing (22.4%), sorting (24.1%), dismantling (50%), and burning (3.4%) e-waste materials. Many blood and urinary elements (including essential ones) were within biomonitoring reference ranges. However, blood cadmium (1.2 ug/L median) and lead (6.4 ug/dl; 67% above U.S. CDC/NIOSH reference level), and urinary arsenic (38.3 ug/L; 39% above U.S. ATSDR value) levels were elevated compared to background populations elsewhere. Workers who burned e-waste tended to have the highest biomarker levels. The findings of this study contribute to a growing body of work at Agbogbloshie (and elsewhere) to document that individuals working within e-waste sites are exposed to a number of toxic elements, some at potentially concerning levels. PMID:27580259

Multiple elemental exposures amongst workers at the Agbogbloshie electronic waste (e-waste) site in Ghana.

PubMed

Srigboh, Roland Kofi; Basu, Niladri; Stephens, Judith; Asampong, Emmanuel; Perkins, Marie; Neitzel, Richard L; Fobil, Julius

2016-12-01

Electronic waste (e-waste) recycling is growing worldwide and raising a number of environmental health concerns. One of the largest e-waste sites is Agbogbloshie (Ghana). While several toxic elements have been reported in Agbogbloshie's environment, there is limited knowledge of human exposures there. The objectives of this study were to characterize exposures to several essential (copper, iron, manganese, selenium, zinc) and toxic (arsenic, cadmium, cobalt, chromium, mercury, nickel, lead) elements in the urine and blood of male workers (n = 58) at Agbogbloshie, as well as females (n = 11) working in activities that serve the site, and to relate these exposures to sociodemographic and occupational characteristics. The median number of years worked at the site was 5, and the average worker indicated being active in 6.8 tasks (of 9 key e-waste job categories). Additionally, we categorized four main e-waste activities (in brackets % of population self-reported main activity): dealing (22.4%), sorting (24.1%), dismantling (50%), and burning (3.4%) e-waste materials. Many blood and urinary elements (including essential ones) were within biomonitoring reference ranges. However, blood cadmium (1.2 μg/L median) and lead (6.4 μg/dl; 67% above U.S. CDC/NIOSH reference level), and urinary arsenic (38.3 μg/L; 39% above U.S. ATSDR value) levels were elevated compared to background populations elsewhere. Workers who burned e-waste tended to have the highest biomarker levels. The findings of this study contribute to a growing body of work at Agbogbloshie (and elsewhere) to document that individuals working within e-waste sites are exposed to a number of toxic elements, some at potentially concerning levels. Copyright © 2016 Elsevier Ltd. All rights reserved.

Records of anthropogenic antimony in the glacial snow from the southeastern Tibetan Plateau

NASA Astrophysics Data System (ADS)

Zhang, Yulan; Kang, Shichang; Chen, Pengfei; Li, Xiaofei; Liu, Yajun; Gao, Tanguang; Guo, Junming; Sillanpää, Mika

2016-12-01

Antimony (Sb) is a ubiquitous element in the environment that is potentially toxic at very low concentrations. In this study, surface snow/ice and snowpit samples were collected from four glaciers in the southeastern Tibetan Plateau in June 2015. The concentrations of Sb and other elements were measured in these samples. The results showed that the average concentration of Sb was approximately 2.58 pg g-1 with a range of 1.64-9.20 pg g-1. The average Sb concentration in the study area was comparable to that recorded in a Mt. Everest ice core and higher than that in Arctic and Antarctic snow/ice but much lower than that in Tien Shan and Alps ice cores. Sb presented different variations with other toxic elements (Pb and Cr) and a crustal element (Al) in the three snowpits, which indicated the impact of a different source or post-deposition processes. The enrichment factor of Sb was larger than 10, suggesting that anthropogenic sources provided important contributions to Sb deposition in the glaciers. The Sb in the glacial snow was mainly loaded in the fourth component in principal component analysis, exhibiting discrepancies with crustal elements (Fe and Ca) and other toxic metals (Pb). Backward trajectories revealed that the air mass arriving at the southeastern Tibetan Plateau mostly originated from the Bay of Bengal and the South Asia in June. Thus, pollutants from the South Asia could play an important role in Sb deposition in the studied region. The released Sb from glacier meltwater in the Tibetan Plateau and surrounding areas might pose a risk to the livelihoods and well-being of those in downstream regions.

URBAN STORMWATER TOXIC POLLUTANTS: ASSESSMENT, SOURCES, AND TREATABILITY

EPA Science Inventory

This paper summarizes an investigation to characterize and treat selected storm water contaminants that are listed as toxic pollutants (termed toxicants in this paper) in the Clean Water Act, Section 307 (Arbuckle et al., 1991). The first project phase investigated typical toxica...

TOXIC TRACE METALS IN MAMMALIAN HAIR AND NAILS

EPA Science Inventory

Data have been compiled from the available world literature on the accumulation and bioconcentration of selected toxic trace metals in human hair and nails and other mammalian hair, fur, nails, claws, and hoofs. The toxic trace metals and metalloids include antimony, arsenic, bor...

Performance of toxicity probability interval based designs in contrast to the continual reassessment method

PubMed Central

Horton, Bethany Jablonski; Wages, Nolan A.; Conaway, Mark R.

2016-01-01

Toxicity probability interval designs have received increasing attention as a dose-finding method in recent years. In this study, we compared the two-stage, likelihood-based continual reassessment method (CRM), modified toxicity probability interval (mTPI), and the Bayesian optimal interval design (BOIN) in order to evaluate each method's performance in dose selection for Phase I trials. We use several summary measures to compare the performance of these methods, including percentage of correct selection (PCS) of the true maximum tolerable dose (MTD), allocation of patients to doses at and around the true MTD, and an accuracy index. This index is an efficiency measure that describes the entire distribution of MTD selection and patient allocation by taking into account the distance between the true probability of toxicity at each dose level and the target toxicity rate. The simulation study considered a broad range of toxicity curves and various sample sizes. When considering PCS, we found that CRM outperformed the two competing methods in most scenarios, followed by BOIN, then mTPI. We observed a similar trend when considering the accuracy index for dose allocation, where CRM most often outperformed both the mTPI and BOIN. These trends were more pronounced with increasing number of dose levels. PMID:27435150

University of Texas Southwestern Medical Center: NSCLC Cell Lines with Loss of SMARCA4 Expression are Hypersensitive to Inhibitors of Aurora Kinase A | Office of Cancer Genomics

Cancer.gov

A genome-wide siRNA screen was employed to identify genes that were selectively toxic for a non-small cell lung cancer (NSCLC) cell line that lacked expression of SMARCA4, but were not toxic in non-cancerous immortalized human bronchial epithelial cells lacking SMARCA4 expression. Among the selectively toxic genes were several mapping to the molecular machinery regulating activity of Aurora kinase A on the mitotic spindle.

University of Texas Southwestern Medical Center (UTSW): NSCLC Cell Lines with Loss of SMARCA4 Expression are Hypersensitive to Inhibitors of Aurora Kinase A | Office of Cancer Genomics

Cancer.gov

A genome-wide siRNA screen was employed to identify genes that were selectively toxic for a non-small cell lung cancer (NSCLC) cell line that lacked expression of SMARCA4, but were not toxic in non-cancerous immortalized human bronchial epithelial cells lacking SMARCA4 expression. Among the selectively toxic genes were several mapping to the molecular machinery regulating activity of Aurora kinase A on the mitotic spindle.

A subchronic toxicity study of elemental Nano-Se in Sprague-Dawley rats.

PubMed

Jia, X; Li, N; Chen, J

2005-03-11

The subchronic toxicity of Nano-Se was compared with selenite and high-selenium protein in rats. Groups of Sprague-Dawley rats (12 males and 12 females per group) were fed diets containing Nano-Se, selenite and high-selenium protein at concentrations of 0, 2, 3, 4 and 5 ppm Se, respectively, for 13 weeks. Clinical observations were made and body weight and food consumption were recorded weekly. At the end of the study, the rats were subjected to a full necropsy, blood samples were collected for hematology and clinical chemistry determination. Histopathological examination was performed on selected tissues. At the two higher doses (4 and 5 ppm Se), significant abnormal changes were found in body weight, hematology, clinical chemistry, relative organ weights and histopathology parameters. However, the toxicity was more pronounced in the selenite and high-selenium protein groups than the Nano-Se group. At the dose of 3 ppm Se, significant growth inhibition and degeneration of liver cells were found in the selenite and high-selenium protein groups. No changes attributable to administration of Nano-Se at the dose of 3 ppm Se were found. Taken together, the no-observed-adverse-effect level (NOAEL) of Nano-Se in male and female rats was considered to be 3 ppm Se, equivalent to 0.22 mg/kg bw/day for males and 0.33 mg/kg bw/day for females. On the other hand, the NOAELs of selenite and high-selenium protein in males and females were considered to be 2 ppm Se, equivalent to 0.14 mg/kg bw/day for males and 0.20 mg/kg bw/day for females. In addition, studies have shown that Nano-Se has a similar bioavailability in rat, and much less acute toxicity in mice compared with selenite. In conclusion, Nano-Se is less toxic than selenite and high-selenium protein in the 13-week rat study.

THE ROLE OF AQUEOUS THIN FILM EVAPORATIVE COOLING ON RATES OF ELEMENTAL MERCURY AIR-WATER EXCHANGE UNDER TEMPERATURE DISEQUILIBRIUM CONDITIONS

EPA Science Inventory

The technical conununity has only recently addressed the role of atmospheric temperature variations on rates of air-water vapor phase toxicant exchange. The technical literature has documented that: 1) day time rates of elemental mercury vapor phase air-water exchange can exceed ...

Processing of a porous titanium alloy from elemental powders using a solid state isothermal foaming technique.

PubMed

Nugroho, Aris W; Leadbeater, Garry; Davies, Ian J

2010-12-01

The authors have conducted a preliminary investigation with regard to the potential to manufacture porous titanium alloys for biomedical applications using toxic-free elemental powders, i.e., Ti, Nb, Ta, Zr, in combination with the pressurised gas bubble entrapment method and in contrast to standard processing routes that generally utilise prealloyed powder containing potentially toxic elements. Elemental powder compacts were either hot isostatic pressed (HIP-ed) at 1000°C and then foamed at 1150°C or else HIP-ed at 1100°C and foamed at 1350°C. Porous α + β alloys containing up to 45 vol% of porosity in the size range 20-200 μm were successfully produced, thus highlighting the potential of this manufacturing route. It was expected that further optimisation of the processing route would allow full development of the preferred β-Ti phase (from the point of view of elastic modulus compatibility between implant and bone) with this being the subject of future work by the authors.

Rice flakes produced from commercial wild rice: Chemical compositions, vitamin B compounds, mineral and trace element contents and their dietary intake evaluation.

PubMed

Sumczynski, Daniela; Koubová, Eva; Šenkárová, Lenka; Orsavová, Jana

2018-10-30

Non-traditional wild rice flakes were analysed for chemical composition, vitamin B compounds, α-tocopherol, mineral and trace elements. Dietary intakes of vitamins, minerals and trace elements were evaluated using FAO/WHO and Institute of Medicine regulations. Wild rice flakes proved to be significant contributors of pyridoxine, pantothenic and folic acids, niacin, thiamine, chromium, magnesium, manganese, phosphorus, zinc, copper, molybdenum and iron to essential dietary intakes values. Toxic dietary intake values for aluminium, cadmium, tin and mercury were less than 33%, which complies the limits for adults set by FAO/WHO for toxic elements intake related to the body weight of 65 kg for females and 80 kg for males taking 100 g of flakes as a portion. However, concentrations of Hg reaching between 3.67 and 12.20 µg/100 g in flakes exceeded the average Hg value of 0.27-1.90 μg/100 g in cereals consumed in the EU. It has to be respected in the future. Copyright © 2018 Elsevier Ltd. All rights reserved.

Monitorization of technosols in old mining sites treated with calcareous fillers

NASA Astrophysics Data System (ADS)

Martínez-Sanchez, MJose; Perez-Sirvent, Carmen; Garcia-Lorenzo, MariLuz; Gonzalez, Eva; Perez-Espinosa, Victor; Martínez-Lopez, Salvadora; Hernandez, Carmen; Molina, Jose; Martínez, Lucia B.

2014-05-01

A large number of soils around the world are contaminated by heavy metals due to mining activities, generating adverse effects on human health and the environment. In response to these negative effects, a variety of technologies to remediate soils affected by heavy metals have been developed. Among them, in situ immobilization by means of soil amendment is a non-intrusive and cost effective alternative, that transforms the highly mobile toxic heavy metals to physico-chemically stable forms, reducing their mobility and environmental risks. Limestone filler is a good selection for such a purpose, because of its low permeability and low solubility, due to its high degree of physical-chemical stability and because is a non-toxic material with a high finely divided calcium carbonate content. In addition, the use of this amendment could revalorize the residues, reducing the costs of the process. The objective of this work was to evaluate the effectiveness of a immobilization technique in sediments contaminated by heavy metals as a results of mining activities. The study area was Portman bay, located close to the mining region of La Unión and subjected to mining from the time of the Roman Empire to 1991. Wastes from mining activities mainly consisted in ore materials (galena, pyrite and sphalerite), phyllosilicates, in addition to siderite, iron oxides and sometimes alteration products such as jarosite, alunite, kaolinite and greenalite. These materials have suffered a concentration process by floatation with sea water and, as a result of the discharge, the whole of the bay has filled up with wastes which also extend into the Mediterranean Sea. Two experimental areas, approximately 1 Ha each one, were selected and technosols were developed as follows: original sediments from the bay, sediments mixed with limestone filler in a 1:1 proportion, gravel to avoid capillary and natural soil to allow plant growth. After the remediation technique was applied, monitorization of experimental areas was done in 18 sampling points in which sediment and water samples were collected and analyzed. Monitorization was carried out during a 4 years period, samples being obtained at two month intervals. The pH and the electrical conductivity were determined, in naddition to the heavy metal concentration. The Zn content was determined by flame atomic absorption spectrometry. The Pb, Cd and Cu content was determined by electrothermal atomization atomic absorption spectrometry. The As content was measured by atomic fluorescence spectrometry using an automated continuous flow hydride generation spectrometer. In addition, Microtox bioassay was applied in order to study ecotoxicity of collected water samples. Sediments before the remediation technique showed acidic pH, high EC values and high trace elements content. The results obtained after the immobilization showed that sediment samples had neutral pH (average value of 8.3) low electrical conductivity (1.32 dS m-1) and low trace elements concentration, in some cases below the detection limit. When water samples obtained in the piezometers were evaluated, the results indicated that these samples correspond to rainfall waters and were characterized by neutral pH and trace elements concentration below the detection limit. In addition, none of them showed toxicity when submitted to the selected bioassay Then, we can conclude that the use of limestone filler constitutes an excellent option in sediments polluted by trace elements, because of risk for human health or ecosystem does not exist or is decreased in a large extent after the intervention. In addition, the designed experience allows stabilizer proportion to be optimized and may suppose a big cost-saving in the project in areas affected by mining activities.

Size distribution and chemical composition of airborne particles in south-eastern Finland during different seasons and wildfire episodes in 2006.

PubMed

Makkonen, Ulla; Hellén, Heidi; Anttila, Pia; Ferm, Martin

2010-01-01

The inorganic main elements, trace elements and PAHs were determined from selected PM(1), PM(2.5) and PM(10) samples collected at the Nordic background station in Virolahti during different seasons and during the wildfire episodes in 2006. Submicron particles are those most harmful to human beings, as they are able to penetrate deep into the human respiratory system and may cause severe health effects. About 70-80%, of the toxic trace elements, like lead, cadmium, arsenic and nickel, as well as PAH compounds, were found in particles smaller than 1 microm. Furthermore, the main part of the copper, zinc, and vanadium was associated with submicron particles. In practice, all the PAHs found in PM(10) were actually in PM(2.5). For PAHs and trace elements, it is more beneficial to analyse the PM(2.5) or even the PM(1) fraction instead of PM(10), because exclusion of the large particles reduces the need for sample cleaning to minimize the matrix effects during the analysis. During the wildfire episodes, the concentrations of particles smaller than 2.5 microm, as well as those of submicron particles, increased, and also the ratio PM(1)/PM(10) increased to about 50%. On the fire days, the mean potassium concentration was higher in all particle fractions, but ammonium and nitrate concentrations rose only in particles smaller than 1.0 microm. PAH concentrations rose even to the same level as in winter.

Determination of reference ranges for elements in human scalp hair.

PubMed

Druyan, M E; Bass, D; Puchyr, R; Urek, K; Quig, D; Harmon, E; Marquardt, W

1998-06-01

Expected values, reference ranges, or reference limits are necessary to enable clinicians to apply analytical chemical data in the delivery of health care. Determination of references ranges is not straightforward in terms of either selecting a reference population or performing statistical analysis. In light of logistical, scientific, and economic obstacles, it is understandable that clinical laboratories often combine approaches in developing health associated reference values. A laboratory may choose to: 1. Validate either reference ranges of other laboratories or published data from clinical research or both, through comparison of patients test data. 2. Base the laboratory's reference values on statistical analysis of results from specimens assayed by the clinical reference laboratory itself. 3. Adopt standards or recommendations of regulatory agencies and governmental bodies. 4. Initiate population studies to validate transferred reference ranges or to determine them anew. Effects of external contamination and anecdotal information from clinicians may be considered. The clinical utility of hair analysis is well accepted for some elements. For others, it remains in the realm of clinical investigation. This article elucidates an approach for establishment of reference ranges for elements in human scalp hair. Observed levels of analytes from hair specimens from both our laboratory's total patient population and from a physician-defined healthy American population have been evaluated. Examination of levels of elements often associated with toxicity serves to exemplify the process of determining reference ranges in hair. In addition the approach serves as a model for setting reference ranges for analytes in a variety of matrices.

A Meta-Analysis and Multisite Time-Series Analysis of the Differential Toxicity of Major Fine Particulate Matter Constituents

PubMed Central

Levy, Jonathan I.; Diez, David; Dou, Yiping; Barr, Christopher D.; Dominici, Francesca

2012-01-01

Health risk assessments of particulate matter less than 2.5 μm in diameter (PM2.5) often assume that all constituents of PM2.5 are equally toxic. While investigators in previous epidemiologic studies have evaluated health risks from various PM2.5 constituents, few have conducted the analyses needed to directly inform risk assessments. In this study, the authors performed a literature review and conducted a multisite time-series analysis of hospital admissions and exposure to PM2.5 constituents (elemental carbon, organic carbon matter, sulfate, and nitrate) in a population of 12 million US Medicare enrollees for the period 2000–2008. The literature review illustrated a general lack of multiconstituent models or insight about probabilities of differential impacts per unit of concentration change. Consistent with previous results, the multisite time-series analysis found statistically significant associations between short-term changes in elemental carbon and cardiovascular hospital admissions. Posterior probabilities from multiconstituent models provided evidence that some individual constituents were more toxic than others, and posterior parameter estimates coupled with correlations among these estimates provided necessary information for risk assessment. Ratios of constituent toxicities, commonly used in risk assessment to describe differential toxicity, were extremely uncertain for all comparisons. These analyses emphasize the subtlety of the statistical techniques and epidemiologic studies necessary to inform risk assessments of particle constituents. PMID:22510275

Biomarkers of Exposure to Toxic Substances. Volume 2: Genomics: Unique Patterns of Differential Gene Expression and Pathway Perturbation Resulting from Exposure to Nephrotoxins with Regional Specific Toxicity

DTIC Science & Technology

2009-05-01

of chemicals agents . Changes in gene expression are among the most sensitive indicators of chemical exposure. Toxicogenomics, which is based on DNA...assessing gene expression changes and subsequently the mechanism of renal injury following exposure to nephrotoxins selected for their regional...Serine Treatment on Selected Serum Chemistry Parameters ........................ 8 Table 4: Effect of PUR Treatment on Selected Serum Chemistry

Zooplankton interactions with toxic phytoplankton: Some implications for food web studies and algal defence strategies of feeding selectivity behaviour, toxin dilution and phytoplankton population diversity

NASA Astrophysics Data System (ADS)

Barreiro, A.; Guisande, C.; Maneiro, I.; Vergara, A. R.; Riveiro, I.; Iglesias, P.

2007-11-01

This study focuses on the interactions between toxic phytoplankton and zooplankton grazers. The experimental conditions used are an attempt to simulate situations that have, so far, received little attention. We presume the phytoplankton community to be a set of species where a population of a toxic species is intrinsically diverse by the presence of coexisting strains with different toxic properties. The other species in the community may not always be high-quality food for herbivorous zooplankton. Zooplankton populations may have developed adaptive responses to sympatric toxic phytoplankton species. Zooplankton grazers may perform a specific feeding behaviour and its consequences on fitness will depend on the species ingested, the effect of toxins, and the presence of mechanisms of toxin dilution and compensatory feeding. Our target species are a strain of the dinoflagellate Alexandrium minutum and a sympatric population of the copepod Acartia clausi. Mixed diets were used with two kinds of A. minutum cells: non-toxic and toxic. The flagellate Rhodomonas baltica and the non-toxic dinoflagellate Alexandrium tamarense were added as accompanying species. The effect of each alga was studied in separate diets. The toxic A. minutum cells were shown to have negative effects on egg production, hatching success and total reproductive output, while, in terms of its effect on fitness, the non-toxic A. minutum was the best quality food offered. R. baltica and A. tamarense were in intermediate positions. In the mixed diets, copepods showed a strong preference for toxic A. minutum cells and a weaker one for A. tamarense cells, while non-toxic A. minutum was slightly negatively selected and R. baltica strongly negatively selected. Although the level of toxins accumulated by copepods was very similar, in both the diet with only toxic A. minutum cells and in the mixed diet, the negative effects on fitness in the mixed diet could be offset by toxin dilution mechanisms. The implications of these findings are the fact that mesozooplankton may not play an important role in phytoplankton blooms development. Phytoplankton endotoxin production does not seem to be an evolutionary stable strategy as a defence against some herbivores.

Aquatic toxicity of petroleum products and dispersant agents ...

EPA Pesticide Factsheets

The U.S. EPA Office of Research and Development has developed baseline data on the ecotoxicity of selected petroleum products and several chemical dispersants as part of its oil spills research program. Two diluted bitumens (dilbits) from the Alberta Tar Sands were tested for acute and chronic toxicity to standard freshwater and marine organisms given their spill potential during shipment within the United States. Separately, two reference crude oils representing a range of characteristics, and their mixtures with four representative dispersants, were tested to evaluate acute and chronic toxicity to marine organisms in support of Subpart J of the U.S. National Contingency Plan. Water accommodated fractions (WAF) of oil were prepared using traditional slow-stir methods and toxicity tests generally followed U.S. EPA standard effluent testing guidelines. WAFs were characterized for petroleum hydrocarbons including alkyl PAH homologs. The results of these studies will assist the U.S. EPA to assess toxicity data for unconventional oils (dilbits), and establish baseline toxicity data for selected crude oils and dispersant in support of planning and response activities. Abstract reporting the results of EPA's oil and dispersant toxicity testing program

Environmental Exposure of Children to Toxic Trace Elements (Hg, Cr, As) in an Urban Area of Yucatan, Mexico: Water, Blood, and Urine Levels.

PubMed

Arcega-Cabrera, F; Fargher, L; Quesadas-Rojas, M; Moo-Puc, R; Oceguera-Vargas, I; Noreña-Barroso, E; Yáñez-Estrada, L; Alvarado, J; González, L; Pérez-Herrera, N; Pérez-Medina, S

2018-05-01

Merida is the largest urban center in the Mexican State of Yucatan. Here domestic sewage is deposited in poorly built septic tanks and is not adequately treated. Because of contamination from such waste, water from the top 20 m of the aquifer is unsuitable for human consumption. Given this situation and because children are highly vulnerable to environmental pollution, including exposure to toxic trace elements, this study focused on evaluating the exposure of children to arsenic (As), chromium (Cr), and mercury (Hg) in water. It also evaluated the relationship between the levels of these elements in water and their concentrations in urine and blood. Among the 33 children monitored in the study, arsenic surpassed WHO limits for blood in 37% of the cases, which could result from the ingestion of poultry contaminated with organoarsenic compounds. In the case of WHO limits for Mercury, 65% of the water samples analyzed, 28% of urine samples, and 12% of blood samples exceeded them. Mercury exposure was correlated with biological sex, some lifestyle factors, and the zone in Merida in which children live. These data suggest that the levels of some toxic metals in children may be affected by water source, socioeconomic factors, and individual behavior.

Water Quality of Camp Creek, Costello Creek, and Other Selected Streams on the South Side of Denali National Park and Preserve, Alaska

USGS Publications Warehouse

Brabets, Timothy P.; Whitman, Matthew S.

2002-01-01

The Camp and Costello Creek watersheds are located on the south side of Denali National Park and Preserve. The Dunkle Mine, an abandoned coal mine, is located near the mouth of Camp Creek. Due to concern about runoff from the mine and its possible effects on the water quality and aquatic habitat of Camp Creek and its receiving stream, Costello Creek, these two streams were studied during the summer runoff months (June to September) in 1999 and 2000 as part of a cooperative study with the National Park Service. Since the south side of Denali National Park and Preserve is part of the U.S. Geological Survey?s National Water-Quality Assessment Cook Inlet Basin study unit, an additional part of this study included analysis of existing water-quality data at 23 sites located throughout the south side of Denali National Park and Preserve to compare with the water quality of Camp and Costello Creeks and to obtain a broader understanding of the water quality in this area of the Cook Inlet Basin. Analysis of water column, bed sediment, fish, invertebrate, and algae data indicate no effects on the water quality of Camp Creek from the Dunkle Mine. Although several organic compounds were found in the streambed of Camp Creek, all concentrations were below recommended levels for aquatic life and most of the concentrations were below the minimum reporting level of 50 ?g/kg. Trace element concentrations of arsenic, chromium, and nickel in the bed sediments of Camp Creek exceeded threshold effect concentrations (TEC), but concentrations of these trace elements were also exceeded in streambed sediments of Costello Creek above Camp Creek. Since the percent organic carbon in Camp Creek is relatively high, the toxicity quotient of 0.55 is only slightly above the threshold value of 0.5. Costello Creek has a relatively low organic carbon content and has a higher toxicity quotient of 1.19. Analysis of the water-quality data for other streams located in the south side of Denali National Park and Preserve indicate similarities to Camp Creek and Costello Creek. Most of the streams are calcium bicarbonate/calcium bicarbonate-sulfate type water with the exception of two streams that are calcium sulfate and magnesium sulfate type water. Trace element concentrations of arsenic, chromium, and nickel in the bed sediments of 9 streams exceeded the TEC or the probable effect concentration (PEC). Seven streams exceeded the threshold value of the toxicity quotient. Analysis of trace element concentrations in bed sediment and basin characteristics for 16 watersheds by cluster and discriminant analysis techniques indicated that the watersheds could be separated into two groups based on their basin characteristics.

Assessment of serum trace elements and electrolytes in children with childhood and atypical autism.

PubMed

Skalny, Anatoly V; Simashkova, Natalia V; Klyushnik, Tatiana P; Grabeklis, Andrei R; Radysh, Ivan V; Skalnaya, Margarita G; Nikonorov, Alexandr A; Tinkov, Alexey A

2017-09-01

The existing data demonstrate a significant interrelation between ASD and essential and toxic trace elements status of the organism. However, data on trace element homeostasis in particular ASD forms are insufficient. Therefore, the objective of the present study was to assess the level of trace elements and electrolytes in serum of children with childhood and atypical autism. A total of 48 children with ASD (24 with childhood and 24 with atypical autism) and age- and sex-adjusted controls were examined. Serum trace elements and electrolytes were assessed using inductively-coupled plasma mass spectrometry. The obtained data demonstrate that children with ASD unspecified are characterized by significantly lower Ni, Cr, and Se levels as compared to the age- and sex-matched controls. At the same time, significantly decreased serum Ni and Se concentrations were detected in patients with childhood autism. In turn, children with atypical autism were characterized by more variable serum trace element spectrum. In particular, atypical autism is associated with lower serum Al, As, Ni, Cr, Mn, and Se levels in comparison to the control values. Moreover, Al and Mn concentration in this group was also lower than that in childhood autism patients. Generally, the obtained data demonstrate lower levels of both essential and toxic trace elements in atypical autism group, being indicative of profound alteration of trace elements metabolism. However, further detailed metabolic studies are required to reveal critical differences in metabolic pathways being responsible for difference in trace element status and clinical course of the disease. Copyright © 2016 Elsevier GmbH. All rights reserved.

Adsorption of oils, heavy metals and dyes by recovered carbon powder from spent pot liner of aluminum smelter plant.

PubMed

Mazumder, B; Devi, Sasmita Rani

2008-07-01

Aluminum smelter plants employ Hall-Heroult electrolysis cells for electrolysis of molten cryolite to recover aluminum metal by electrolysis. These cells use carbon cathode blocks as a lining material inside. At the end of service life of the cells, pot lines are discarded and new carbon blocks are laid for fresh charging. These used carbon cathode blocks, known as spent pot liners, are heavily infested with toxic elements such as fluoride, cyanide, alkali, etc. Therefore, their disposal in open field poses great environmental risk. A simple process has been developed for decontamination of these spent pot liners and to recover its carbon value. The experiments indicated that this carbon, in the form of fine powder (around 20 micron in size) can absorb toxic elements like heavy metals, dyes, oils, etc. to a great extent and thus can be used for mitigating environmental pollution occuring due to various toxic wastes.

In Vitro Methods To Measure Toxicity Of Chemicals

DTIC Science & Technology

2004-12-01

industrial compounds for toxicity will require high-throughput in vitro assays with which to select candidate compounds for more intensive animal...for estimating the starting dose for the rat oral acute toxicity test, thus reducing and refining the use of animals in the toxicological

Prediction of the developmental toxicity hazard potential of halogenated drinking water disinfection by-products tested by the in vitro hydra assay

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

Fu, L.J.; Johnson, E.M.; Newman, L.M.

A series of seven randomly selected potential halogenated water disinfection by-products were evaluated in vitro by the hydra assay to determine their developmental toxicity hazard potential. For six of the chemicals tested by this assay (dibromoacetonitrile; trichloroacetonitrile; 2-chlorophenol; 2,4,6-trichlorophenol; trichloroacetic acid; dichloroacetone) it was predicted that they would be generally equally toxic to both adult and embryonic mammals when studied by means of standard developmental toxicity teratology tests. However, the potential water disinfection by-product chloroacetic acid (CA) was determined to be over eight times more toxic to the embryonic developmental portion of the assay than it was to the adults.more » Because of this potential selectivity, CA is a high-priority item for developmental toxicity tests in pregnant mammals to confirm or refute its apparent unique developmental hazard potential and/or to establish a NOAEL by the route of most likely human exposure.« less

Potentially toxic elements in soil of the Khyber Pakhtunkhwa province and Tribal areas, Pakistan: evaluation for human and ecological risk assessment.

PubMed

Saddique, Umar; Muhammad, Said; Tariq, Mohsin; Zhang, Hua; Arif, Mohammad; Jadoon, Ishtiaq A K; Khattak, Nimat Ullah

2018-03-22

Potentially toxic elements (PTEs) contaminations in the soil ecosystem are considered as extremely hazardous due to toxicity, persistence and bioaccumulative nature. Therefore, this study was aimed to summarize the results of published PTEs in soil of Khyber Pakhtunkhwa and Tribal areas, Pakistan. Results were evaluated for the pollution quantification factors, including contamination factor (CF), pollution load index (PLI), ecological risk index (ERI) and human health risk assessment. The highest CF (797) and PLI (7.35) values were observed for Fe and ERI (857) values for Cd. Soil PTEs concentrations were used to calculate the human exposure for the risk assessment, including chronic or non-carcinogenic risks such as the hazard quotient (HQ) and carcinogenic or cancer risk (CR). The values of HQ were > 1 for the Cd, Co and Cr in Khyber Pakhtunkhwa and Tribal areas. Tribal areas showed higher values of ERI, HQ, and CR as compared to the Khyber Pakhtunkhwa that were attributed to the mining activities, weathering and erosion of mafic and ultramafic bedrocks hosting ophiolites. This study strongly recommends that best control measures need to be taken for soil PTEs with the intent to alleviate any continuing potential threat to the human health, property and environment, which otherwise could enter ecosystem and ultimately the living beings. Further studies are recommended to combat the soil PTEs concentrations and toxicity in the Tribal areas for a best picture of understanding the element effects on human, and environment can be achieved that will lead to a sustainable ecological harmony.

Evaluation of Toxicological Effects of an Aqueous Extract of Shells from the Pecan Nut Carya illinoinensis (Wangenh.) K. Koch and the Possible Association with Its Inorganic Constituents and Major Phenolic Compounds.

PubMed

Porto, Luiz Carlos S; da Silva, Juliana; Sousa, Karen; Ambrozio, Mariana L; de Almeida, Aline; Dos Santos, Carla Eliete I; Dias, Johnny F; Allgayer, Mariangela C; Dos Santos, Marcela S; Pereira, Patrícia; Ferraz, Alexandre B F; Picada, Jaqueline N

2016-01-01

Background. Industrial processing of the pecan nut Carya illinoinensis K. Koch generated a large amount of shells, which have been used to prepare nutritional supplements and medicinal products; however, the safe use of shells requires assessment. This study evaluated the toxic, genotoxic, and mutagenic effects of pecan shell aqueous extract (PSAE) and the possible contribution of phenolic compounds, ellagic and gallic acids, and inorganic elements present in PSAE to induce toxicity. Results. Levels of inorganic elements like K, P, Cl, and Rb quantified using the Particle-Induced X-Ray Emission method were higher in PSAE than in pecan shells, while Mg and Mn levels were higher in shells. Mice showed neurobehavioral toxicity when given high PSAE doses (200-2,000 mg kg(-1)). The LD50 was 1,166.3 mg kg(-1). However, PSAE (50-200 mg·kg(-1)) and the phenolic compounds (10-100 mg·kg(-1)) did not induce DNA damage or mutagenicity evaluated using the comet assay and micronucleus test. Treatment with ellagic acid (10-100 mg·kg(-1)) decreased triglyceride and glucose levels, while treatments with PSAE and gallic acid had no effect. Conclusion. Pecan shell toxicity might be associated with high concentrations of inorganic elements such as Mn, Al, Cu, and Fe acting on the central nervous system, besides phytochemical components, suggesting that the definition of the safe dose should take into account the consumption of micronutrients.

Evaluation of Toxicological Effects of an Aqueous Extract of Shells from the Pecan Nut Carya illinoinensis (Wangenh.) K. Koch and the Possible Association with Its Inorganic Constituents and Major Phenolic Compounds

PubMed Central

Porto, Luiz Carlos S.; Sousa, Karen; Ambrozio, Mariana L.; de Almeida, Aline; dos Santos, Carla Eliete I.; Dias, Johnny F.; Allgayer, Mariangela C.; dos Santos, Marcela S.; Pereira, Patrícia; Picada, Jaqueline N.

2016-01-01

Background. Industrial processing of the pecan nut Carya illinoinensis K. Koch generated a large amount of shells, which have been used to prepare nutritional supplements and medicinal products; however, the safe use of shells requires assessment. This study evaluated the toxic, genotoxic, and mutagenic effects of pecan shell aqueous extract (PSAE) and the possible contribution of phenolic compounds, ellagic and gallic acids, and inorganic elements present in PSAE to induce toxicity. Results. Levels of inorganic elements like K, P, Cl, and Rb quantified using the Particle-Induced X-Ray Emission method were higher in PSAE than in pecan shells, while Mg and Mn levels were higher in shells. Mice showed neurobehavioral toxicity when given high PSAE doses (200–2,000 mg kg−1). The LD50 was 1,166.3 mg kg−1. However, PSAE (50–200 mg·kg−1) and the phenolic compounds (10–100 mg·kg−1) did not induce DNA damage or mutagenicity evaluated using the comet assay and micronucleus test. Treatment with ellagic acid (10–100 mg·kg−1) decreased triglyceride and glucose levels, while treatments with PSAE and gallic acid had no effect. Conclusion. Pecan shell toxicity might be associated with high concentrations of inorganic elements such as Mn, Al, Cu, and Fe acting on the central nervous system, besides phytochemical components, suggesting that the definition of the safe dose should take into account the consumption of micronutrients. PMID:27525021

Mercury toxicity and antioxidants: Part 1: role of glutathione and alpha-lipoic acid in the treatment of mercury toxicity.

PubMed

Patrick, Lyn

2002-12-01

Mercury exposure is the second-most common cause of toxic metal poisoning. Public health concern over mercury exposure, due to contamination of fish with methylmercury and the elemental mercury content of dental amalgams, has long been a topic of political and medical debate. Although the toxicology of mercury is complex, there is evidence for antioxidant protection in the prevention of neurological and renal damage caused by mercury toxicity. Alpha-lipoic acid, a coenzyme of pyruvate and alpha-ketoglutarate dehydrogenase, has been used in Germany as an antioxidant and approved treatment for diabetic polyneuropathy for 40 years. Research has attempted to identify the role of antioxidants, glutathione and alpha-lipoic acid specifically, in both mitigation of heavy metal toxicity and direct chelation of heavy metals. This review of the literature will assess the role of glutathione and alpha-lipoic acid in the treatment of mercury toxicity.

Uranium in well drinking water of Kabul, Afghanistan and its effective, low-cost depuration using Mg-Fe based hydrotalcite-like compounds.

PubMed

Kato, Masashi; Azimi, Mohammad Daud; Fayaz, Said Hafizullah; Shah, Muhammad Dawood; Hoque, Md Zahirul; Hamajima, Nobuyuki; Ohnuma, Shoko; Ohtsuka, Tomomi; Maeda, Masao; Yoshinaga, Masafumi

2016-12-01

Toxic elements in drinking water have great effects on human health. However, there is very limited information about toxic elements in drinking water in Afghanistan. In this study, levels of 10 elements (chromium, nickel, copper, arsenic, cadmium, antimony, barium, mercury, lead and uranium) in 227 well drinking water samples in Kabul, Afghanistan were examined for the first time. Chromium (in 0.9% of the 227 samples), arsenic (7.0%) and uranium (19.4%) exceeded the values in WHO health-based guidelines for drinking-water quality. Maximum chromium, arsenic and uranium levels in the water samples were 1.3-, 10.4- and 17.2-fold higher than the values in the guidelines, respectively. We next focused on uranium, which is the most seriously polluted element among the 10 elements. Mean ± SD (138.0 ± 1.4) of the 238 U/ 235 U isotopic ratio in the water samples was in the range of previously reported ratios for natural source uranium. We then examined the effect of our originally developed magnesium (Mg)-iron (Fe)-based hydrotalcite-like compounds (MF-HT) on adsorption for uranium. All of the uranium-polluted well water samples from Kabul (mean ± SD = 190.4 ± 113.9 μg/L; n = 11) could be remediated up to 1.2 ± 1.7 μg/L by 1% weight of our MF-HT within 60 s at very low cost (<0.001 cents/day/family) in theory. Thus, we demonstrated not only elevated levels of some toxic elements including natural source uranium but also an effective depurative for uranium in well drinking water from Kabul. Since our depurative is effective for remediation of arsenic as shown in our previous studies, its practical use in Kabul may be encouraged. Copyright © 2016 Elsevier Ltd. All rights reserved.

Applications of diatoms as potential microalgae in nanobiotechnology.

PubMed

Jamali, Ali Akbar; Akbari, Fariba; Ghorakhlu, Mohamad Moradi; de la Guardia, Miguel; Yari Khosroushahi, Ahmad

2012-01-01

Diatoms are single cell eukaryotic microalgae, which present in nearly every water habitat make them ideal tools for a wide range of applications such as oil explora-tion, forensic examination, environmental indication, biosilica pattern generation, toxicity testing and eutrophication of aqueous ecosystems. Essential information on diatoms were reviewed and discussed towards impacts of diatoms on biosynthesis and bioremediation. In this review, we present the recent progress in this century on the application of diatoms in waste degradation, synthesis of biomaterial, biomineraliza-tion, toxicity and toxic effects of mineral elements evaluations. Diatoms can be considered as metal toxicity bioindicators and they can be applied for biomineralization, synthesis of biomaterials, and degradation of wastes.

Potentially Toxic Element Uptake by Bacillus jeotgali Strain U3: A Natural Attenuation Mechanism in polluted sediments from Estero de Urías Coastal Lagoon (SE Gulf of California)?

NASA Astrophysics Data System (ADS)

Green-Ruiz, C. R.; Rodríguez-Tirado, V. A.; Carrasco-Valenzuela, A. C.; Gómez-Gil, B.

2007-05-01

In addition to an increased flux of potentially toxic elements (PTE's) into aquatic ecosystems, toxicity, bioavailability and persistency of these pollutants have led to critical localized pollution sites around the world, and the risk for the environment and the health of organism, including humans, has been increased. Clean-up technologies for the treatment of huge volumes of water, sediments and soils contaminated with these elements are needed. Use of bacteria as concentrators of PTE's can become a good tool for the remediation of man- impacted coastal ecosystems. A subtropical estuarine bacterium was isolate from surface sediments from Estero de Urías coastal lagoon, Mazatlán, Mexico, which is an aquatic ecosystem surrounded by several anthropogenic that release PTE's into the environment. This bacterial strain (U3) was ascertained (16s rRNA analysis) to belong to the Bacillus jeotgali specie. Batch experiments with different bacterial biomass and PTE (Cd, Cu, Hg, Pb and Zn) concentrations, pH and temperature were carried out in order to evaluate the biosorption capacity of Bacillus jeotgali strain U3. Except data from Zn experiments, all values were fitted to the adsorption Langmuir model. The maximum adsorption capacities (qmax) were 58 mg Cd g-1, 27 mg Cu g-1, 191 mg Hg g-1 (viable biomass), 21 mg Hg g-1 (non-viable biomass), 90 mg Pb g-1. Adsorption of Zn was 350 mg g-1, when equilibrium concentration in solution was 130 mg Zn l-1. According our data, Bacillus jeotgali strain U3 is considered as a suitable adsorbent and the presence of this microorganism in Estero de Urías coastal lagoon can produce a natural attenuation of potentially toxic elements pollution.

Selenite reduction by the obligate aerobic bacterium Comamonas testosteroni S44 isolated from a metal-contaminated soil

PubMed Central

2014-01-01

Background Selenium (Se) is an essential trace element in most organisms but has to be carefully handled since there is a thin line between beneficial and toxic concentrations. Many bacteria have the ability to reduce selenite (Se(IV)) and (or) selenate (Se(VI)) to red elemental selenium that is less toxic. Results A strictly aerobic bacterium, Comamonas testosteroni S44, previously isolated from metal(loid)-contaminated soil in southern China, reduced Se(IV) to red selenium nanoparticles (SeNPs) with sizes ranging from 100 to 200 nm. Both energy dispersive X-ray Spectroscopy (EDX or EDS) and EDS Elemental Mapping showed no element Se and SeNPs were produced inside cells whereas Se(IV) was reduced to red-colored selenium in the cytoplasmic fraction in presence of NADPH. Tungstate inhibited Se(VI) but not Se(IV) reduction, indicating the Se(IV)-reducing determinant does not contain molybdenum as co-factor. Strain S44 was resistant to multiple heavy and transition metal(loid)s such as Se(IV), As(III), Cu(II), and Cd(II) with minimal inhibitory concentrations (MIC) of 100 mM, 20 mM, 4 mM, and 0.5 mM, respectively. Disruption of iscR encoding a transcriptional regulator negatively impacted cellular growth and subsequent resistance to multiple heavy metal(loid)s. Conclusions C. testosteroni S44 could be very useful for bioremediation in heavy metal(loid) polluted soils due to the ability to both reduce toxic Se(VI) and Se(IV) to non-toxic Se (0) under aerobic conditions and to tolerate multiple heavy and transition metals. IscR appears to be an activator to regulate genes involved in resistance to heavy or transition metal(loid)s but not for genes responsible for Se(IV) reduction. PMID:25098921

Divalent Naphthalene Diimide Ligands Display High Selectivity for the Human Telomeric G‐quadruplex in K+ Buffer

PubMed Central

Street, Steven T. G.; Chin, Donovan N.; Hollingworth, Gregory J.; Berry, Monica

2017-01-01

Abstract Selective G‐quadruplex ligands offer great promise for the development of anti‐cancer therapies. A novel series of divalent cationic naphthalene diimide ligands that selectively bind to the hybrid form of the human telomeric G‐quadruplex in K+ buffer are described herein. We demonstrate that an imidazolium‐bearing mannoside‐conjugate is the most selective ligand to date for this quadruplex against several other quadruplex and duplex structures. We also show that a similarly selective methylpiperazine‐bearing ligand was more toxic to HeLa cancer cells than doxorubicin, whilst exhibiting three times less toxicity towards fetal lung fibroblasts WI‐38. PMID:28257554

Analysis of the Toxic Element Concentrations in the Mesozoic Siliceous Rocks in Terms of the Raw Material Importance

NASA Astrophysics Data System (ADS)

Pękala, Agnieszka

2017-10-01

As part of an integrated system of environmental protection at every stage of the product life cycle such as: raw material extraction, its transportation and processing as well the subsequent use and development is required to carry out actions towards reducing or completely eliminating products that contain harmful substances to the environment. The purpose of the presented paper is an analysis of the toxic element concentrations in the extracted siliceous minerals at the initial stage of the raw material recognition. The research material is constituted by rocks collected from the Mesozoic bedrock from the Bełchatów lignite deposit. A group of the studied rocks is represented by diatomites, gaizes, opoka-rocks and light opoka-rocks, enriched with minerals from the group of SiO2. Most of the recognized petrographic sediments have a real possibility of potential applications in the building material industry, but it needs to carry out a detailed and thorough research. The studies of the chemical composition were determined by atomic absorption spectroscopy (AAS) using Philips PU 9100Xi Camera SX-100 spectrometer and an atomic emission spectroscopy with inductively coupled plasma (ICP AES) using PLASMA 40 spectrometer. There were carried out a chemical analyses and determined the content of some toxic elements: Pb, Cr, Cd, Ni, Zn, Cu, Co, As, Sr, Ba, Zr. in the studied sedimentary rocks. The analysis of the results draws attention to the high content of cadmium in the case of the studied sediments. The concentration of this element in the described rocks is an average of 0.22 mg/kg -the diatomites, 0.05 mg/kg -the gaizes, 0.4 mg/kg -the opoka-rocks, 2.23 mg/kg -the light opoka-rocks. It was moreover registered varied concentration of arsenic in diatomites, that is formed in the range of 0.05 - 9.6 mg/kg, an average of 6.3 mg/kg. The content of the other designated elements with toxic properties in the analysed groups of rocks does not exceed the limit values. An increased concentration of cadmium and arsenic should be considered as an important information in resource research of the studied rocks. The both elements belong to the easily soluble elements as a result of weathering processes. Cadmium is one of the most dangerous toxicological environmental elements. It is easily absorbed and relatively long stopped in humans and animal’s organism. It also seems that the increased concentration in the siliceous rocks results from the nature of the lignite from the Bełchatów lignite deposit, outstanding higher cadmium content in relation to the observed lignite of the world.

Physical linkage of metabolic genes in fungi is an adaptation against the accumulation of toxic intermediate compounds.

PubMed

McGary, Kriston L; Slot, Jason C; Rokas, Antonis

2013-07-09

Genomic analyses have proliferated without being tied to tangible phenotypes. For example, although coordination of both gene expression and genetic linkage have been offered as genetic mechanisms for the frequently observed clustering of genes participating in fungal metabolic pathways, elucidation of the phenotype(s) favored by selection, resulting in cluster formation and maintenance, has not been forthcoming. We noted that the cause of certain well-studied human metabolic disorders is the accumulation of toxic intermediate compounds (ICs), which occurs when the product of an enzyme is not used as a substrate by a downstream neighbor in the metabolic network. This raises the hypothesis that the phenotype favored by selection to drive gene clustering is the mitigation of IC toxicity. To test this, we examined 100 diverse fungal genomes for the simplest type of cluster, gene pairs that are both metabolic neighbors and chromosomal neighbors immediately adjacent to each other, which we refer to as "double neighbor gene pairs" (DNGPs). Examination of the toxicity of their corresponding ICs shows that, compared with chromosomally nonadjacent metabolic neighbors, DNGPs are enriched for ICs that have acutely toxic LD50 doses or reactive functional groups. Furthermore, DNGPs are significantly more likely to be divergently oriented on the chromosome; remarkably, ∼40% of these DNGPs have ICs known to be toxic. We submit that the structure of synteny in metabolic pathways of fungi is a signature of selection for protection against the accumulation of toxic metabolic intermediates.

Physical linkage of metabolic genes in fungi is an adaptation against the accumulation of toxic intermediate compounds

PubMed Central

McGary, Kriston L.; Slot, Jason C.; Rokas, Antonis

2013-01-01

Genomic analyses have proliferated without being tied to tangible phenotypes. For example, although coordination of both gene expression and genetic linkage have been offered as genetic mechanisms for the frequently observed clustering of genes participating in fungal metabolic pathways, elucidation of the phenotype(s) favored by selection, resulting in cluster formation and maintenance, has not been forthcoming. We noted that the cause of certain well-studied human metabolic disorders is the accumulation of toxic intermediate compounds (ICs), which occurs when the product of an enzyme is not used as a substrate by a downstream neighbor in the metabolic network. This raises the hypothesis that the phenotype favored by selection to drive gene clustering is the mitigation of IC toxicity. To test this, we examined 100 diverse fungal genomes for the simplest type of cluster, gene pairs that are both metabolic neighbors and chromosomal neighbors immediately adjacent to each other, which we refer to as “double neighbor gene pairs” (DNGPs). Examination of the toxicity of their corresponding ICs shows that, compared with chromosomally nonadjacent metabolic neighbors, DNGPs are enriched for ICs that have acutely toxic LD50 doses or reactive functional groups. Furthermore, DNGPs are significantly more likely to be divergently oriented on the chromosome; remarkably, ∼40% of these DNGPs have ICs known to be toxic. We submit that the structure of synteny in metabolic pathways of fungi is a signature of selection for protection against the accumulation of toxic metabolic intermediates. PMID:23798424

Validation of the proteasome as a therapeutic target in Plasmodium using an epoxyketone inhibitor with parasite-specific toxicity

PubMed Central

Li, Hao; Ponder, Elizabeth L.; Verdoes, Martijn; Asbjornsdottir, Kristijana H.; Deu, Edgar; Edgington, Laura E.; Lee, Jeong Tae; Kirk, Christopher J.; Demo, Susan D.; Williamson, Kim C.; Bogyo, Matthew

2012-01-01

Summary The Plasmodium proteasome has been suggested to be a potential anti-malarial drug target, however toxicity of inhibitors has prevented validation of this enzyme in vivo. We report here a screen of a library of 670 analogs of the recently FDA approved inhibitor, carfilzomib, to identify compounds that selectively kill parasites. We identified one compound, PR3, that has significant parasite killing activity in vitro but dramatically reduced toxicity in host cells. We found that this parasite-specific toxicity is not due to selective targeting of the Plasmodium proteasome over the host proteasome, but instead is due to a lack of activity against one of the human proteasome subunits. Subsequently, we used PR3 to significantly reduce parasite load in P. berghei infected mice without host toxicity, thus validating the proteasome as a viable anti-malarial drug target. PMID:23142757

Chemical, Biochemical, and Genetic Approaches to Arsenic Metabolism" -An overview of arsenic metabolism and toxicity- A series of five papers to appear together in Current Protocols in Toxicology

EPA Science Inventory

The toxic properties of arsenic (As) were recognized long before Albertus Magnus in the 13th century prepared its elemental form (Buchanan, 1962). Its use as a poison has played lethal and decisive roles in domestic and dynastic intrigues throughout history (Cullen, 2008). Inorga...

When dinner is dangerous: toxic frogs elicit species-specific responses from a generalist snake predator.

PubMed

Phillips, Ben; Shine, Richard

2007-12-01

In arms races between predators and prey, some evolved tactics are unbeatable by the other player. For example, many types of prey are inedible because they have evolved chemical defenses. In this case, prey death removes any selective advantage of toxicity to the prey but not the selective advantage to a predator of being able to consume the prey. In the absence of effective selection for postmortem persistence of the toxicity then, some chemical defenses probably break down rapidly after prey death. If so, predators can overcome the toxic defense simply by waiting for that breakdown before consuming the prey. Floodplain death adders (Acanthophis praelongus) are highly venomous frog-eating elapid snakes native to northern Australia. Some of the frogs they eat are nontoxic (Litoria nasuta), others produce gluelike mucus when seized by a predator (Limnodynastes convexiusculus), and one species (Litoria dahlii) is dangerously toxic to snakes. Both the glue and the toxin degrade within about 20 min of prey death. Adders deal with these prey types in different and highly stereotyped ways: they consume nontoxic frogs directly but envenomate and release the other taxa, waiting until the chemical defense loses its potency before consuming the prey.

Enrichment of rare earth metal ions by the highly selective adsorption of phytate intercalated layered double hydroxide.

PubMed

Jin, Cheng; Liu, Huimin; Kong, Xianggui; Yan, Hong; Lei, Xiaodong

2018-02-27

Phytate intercalated MgAl layered double hydroxide (MgAl-LDH) was prepared by an anion exchange method with the precursor NO 3 - containing MgAl-LDH. The final as-synthesized product [Mg 0.69 Al 0.31 (OH) 2 ] (phytateNa 6 ) 0.05 (NO 3 ) 0.01 ·mH 2 O (phytate-LDH) has highly selective adsorption ability for some metal ions and can be used to enrich rare earth metal ions in mixed solution, such as Pr 3+ and Ce 3+ from a mixed solution of them with Pb 2+ and Co 2+ . At first, phytate-LDH has good adsorption performance for these ions in single metal ion solutions. At low concentration (below 10 mg L -1 ), all the capture rates of the four metal ions were more than 97%, for highly toxic Pb 2+ it was even up to nearly 100%, and a high capture rate (99.87%) was maintained for Pb 2+ at a high concentration (100 mg L -1 ). When all the four metal ions are co-existing in aqueous solution, the selectivity order is Pb 2+ ≫ Pr 3+ ≈ Ce 3+ > Co 2+ . In a solution containing mixtures of the three metal ions of Pr 3+ , Ce 3+ , and Co 2+ , the selectivity order is Pr 3+ ≈ Ce 3+ ≫ Co 2+ , and in a solution containing mixtures of Pr 3+ with Co 2+ and Ce 3+ with Co 2+ , the selectivity orders are Pr 3+ ≫ Co 2+ and Ce 3+ ≫ Co 2+ , respectively. The high selectivity and adsorption capacities for Pb 2+ , Co 2+ , Pr 3+ , and Ce 3+ result in the efficient removal of Pb 2+ and enrichment of the rare earth metal ions Pr 3+ and Ce 3+ by phytate-LDH. Based on the elemental analysis, it is found that the difference of the adsorption capacities is mainly due to the different coordination number of them with phytate-LDH. With molecular simulation, we believe that the adsorption selectivity is due to the difference of the binding energy between the metal ion and phytate-LDH. Therefore, the phytate-LDH is promising for the enrichment and/or purification of the rare earth metal ions and removal of toxic metal ions from waste water.

Modeling adverse event counts in phase I clinical trials of a cytotoxic agent.

PubMed

Muenz, Daniel G; Braun, Thomas M; Taylor, Jeremy Mg

2018-05-01

Background/Aims The goal of phase I clinical trials for cytotoxic agents is to find the maximum dose with an acceptable risk of severe toxicity. The most common designs for these dose-finding trials use a binary outcome indicating whether a patient had a dose-limiting toxicity. However, a patient may experience multiple toxicities, with each toxicity assigned an ordinal severity score. The binary response is then obtained by dichotomizing a patient's richer set of data. We contribute to the growing literature on new models to exploit this richer toxicity data, with the goal of improving the efficiency in estimating the maximum tolerated dose. Methods We develop three new, related models that make use of the total number of dose-limiting and low-level toxicities a patient experiences. We use these models to estimate the probability of having at least one dose-limiting toxicity as a function of dose. In a simulation study, we evaluate how often our models select the true maximum tolerated dose, and we compare our models with the continual reassessment method, which uses binary data. Results Across a variety of simulation settings, we find that our models compare well against the continual reassessment method in terms of selecting the true optimal dose. In particular, one of our models which uses dose-limiting and low-level toxicity counts beats or ties the other models, including the continual reassessment method, in all scenarios except the one in which the true optimal dose is the highest dose available. We also find that our models, when not selecting the true optimal dose, tend to err by picking lower, safer doses, while the continual reassessment method errs more toward toxic doses. Conclusion Using dose-limiting and low-level toxicity counts, which are easily obtained from data already routinely collected, is a promising way to improve the efficiency in finding the true maximum tolerated dose in phase I trials.

Distribution of toxic alkaloids in tissues from three herbal medicine Aconitum species using laser micro-dissection, UHPLC-QTOF MS and LC-MS/MS techniques.

PubMed

Jaiswal, Yogini; Liang, Zhitao; Ho, Alan; Wong, LaiLai; Yong, Peng; Chen, Hubiao; Zhao, Zhongzhen

2014-11-01

Aconite poisoning continues to be a major type of poisoning caused by herbal drugs in many countries. Nevertheless, despite its toxic characteristics, aconite is used because of its valuable therapeutic benefits. The aim of the present study was to determine the distribution of toxic alkaloids in tissues of aconite roots through chemical profiling. Three species were studied, all being used in traditional Chinese Medicine (TCM) and traditional Indian medicine (Ayurveda), namely: Aconitum carmichaelii, Aconitum kusnezoffii and Aconitum heterophyllum. Laser micro-dissection was used for isolation of target microscopic tissues, such as the metaderm, cortex, xylem, pith, and phloem, with ultra-high performance liquid chromatography equipped with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS) employed for detection of metabolites. Using a multi-targeted approach through auto and targeted LC-MS/MS, 48 known compounds were identified and the presence of aconitine, mesaconitine and hypaconitine that are the biomarkers of this plant was confirmed in the tissues. These results suggest that the three selected toxic alkaloids were exclusively found in A. carmichaelii and A. kusnezoffii. The most toxic components were found in large A. carmichaelii roots with more lateral root projections, and specifically in the metaderm, cork and vascular bundle tissues. The results from metabolite profiling were correlated with morphological features to predict the tissue specific distribution of toxic components and toxicity differences among the selected species. By careful exclusion of tissues having toxic diester diterpenoid alkaloids, the beneficial effects of aconite can still be retained and the frequency of toxicity occurrences can be greatly reduced. Knowledge of tissue-specific metabolite distribution can guide users and herbal drug manufacturers in prudent selection of relatively safer and therapeutically more effective parts of the root. The information provided from this study can contribute towards improved and effective management of therapeutically important, nonetheless, toxic drug such as Aconite. Copyright © 2014 Elsevier Ltd. All rights reserved.

The role of genetic background in susceptibility to chemical warfare nerve agents across rodent and non-human primate models.

PubMed

Matson, Liana M; McCarren, Hilary S; Cadieux, C Linn; Cerasoli, Douglas M; McDonough, John H

2018-01-15

Genetics likely play a role in various responses to nerve agent exposure, as genetic background plays an important role in behavioral, neurological, and physiological responses to environmental stimuli. Mouse strains or selected lines can be used to identify susceptibility based on background genetic features to nerve agent exposure. Additional genetic techniques can then be used to identify mechanisms underlying resistance and sensitivity, with the ultimate goal of developing more effective and targeted therapies. Here, we discuss the available literature on strain and selected line differences in cholinesterase activity levels and response to nerve agent-induced toxicity and seizures. We also discuss the available cholinesterase and toxicity literature across different non-human primate species. The available data suggest that robust genetic differences exist in cholinesterase activity, nerve agent-induced toxicity, and chemical-induced seizures. Available cholinesterase data suggest that acetylcholinesterase activity differs across strains, but are limited by the paucity of carboxylesterase data in strains and selected lines. Toxicity and seizures, two outcomes of nerve agent exposure, have not been fully evaluated for genetic differences, and thus further studies are required to understand baseline strain and selected line differences. Published by Elsevier B.V.

Trace element accumulation in bivalve mussels Anodonta woodiana from Taihu Lake, China.

PubMed

Liu, Hongbo; Yang, Jian; Gan, Juli

2010-11-01

Data are presented for 13 trace metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, and Pb) in 38 bivalve mussels Anodonta woodiana from four separate sites (Huzhou, Dapu, Sansandao, and Manshan) around the Taihu Lake of China. All elemental concentrations generally ranked in decreasing order, Mn > Fe > Zn > As ≈ Cu ≈ Cd ≈ Se > Pb > Mo ≈ Ag, except that Cr, Co, and Ni were not detected. Anodonta woodiana was able to bioaccumulate essential Mn and toxic Cd to the extremely high level of 19,240 and 53 mg/kg dry weight, respectively. Geographical differences in the concentrations of trace elements were usually significant between sampling sites except for As and Pb, and the mussels from Sanshandao site had mostly accumulated or were contaminated with essential and toxic elements. The residue level of Cd in A. woodiana from the Sanshandao and Manshan sites appeared to be even higher than those of the essential elements Cu and Se, and exceeded the corresponding maximum residue limits of China. The present study provides the most recent information on trace element bioaccumulation or contamination in Taihu Lake and, further, suggests that A. woodiana can be used as a suitable bioindicator for inland water environmental monitoring.

Effective Message Elements for Disclosures about Chemicals in Cigarette Smoke.

PubMed

Kelley, Dannielle E; Boynton, Marcella H; Noar, Seth M; Morgan, Jennifer C; Mendel, Jennifer R; Ribisl, Kurt M; Stepanov, Irina; Nylander-French, Leena A; Brewer, Noel T

2017-05-17

Cigarette smoke contains at least 93 chemicals or "constituents" that the Food and Drug Administration (FDA) has identified as harmful or potentially harmful to human health. Our study sought to identify which constituent disclosure message elements are most effective in discouraging people from smoking. Three hundred eighty-eight current smokers ages 18 and older completed an online survey in February 2015. We randomized participants to respond to one of two sets of 13 toxic products that contain cigarette constituents and 25 health effects associated with cigarette constituents. Products that elicited the most discouragement were those with lower chances of exposure (e.g., explosives), followed by products with possible exposure (e.g., rat poison) and products with a high likelihood of exposure (e.g., floor cleaner). Awareness of toxic products that constituents are found in (p<0.001) and low exposure products (p<0.001) were associated with higher discouragement. Health effects that people had heard are caused by cigarette smoke constituents elicited higher discouragement from smoking cigarettes (p<0.001). Cancer was associated with higher discouragement relative to respiratory, cardiovascular, and reproductive health effects (all p<0.001). Cigarette smoke constituent messages may discourage smoking if they include information about carcinogenic health effects (e.g., mouth cancer, lung tumors) and low exposure toxic products (e.g. explosives, radioactive material) may be particularly effective message elements. Our study identified health effects and toxic products, especially cancers and rarely encountered toxic products, that may discourage smoking when included in disclosure messages. By constructing messages that communicate the harms associated with tobacco use by contextualizing those harms in terms of specific constituents, tobacco education messaging efforts may be increasingly successful. © The Author 2017. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Exposures to multiple air toxics in New York City.

PubMed Central

Kinney, Patrick L; Chillrud, Steven N; Ramstrom, Sonja; Ross, James; Spengler, John D

2002-01-01

Efforts to assess health risks associated with exposures to multiple urban air toxics have been hampered by the lack of exposure data for people living in urban areas. The TEACH (Toxic Exposure Assessment, a Columbia/Harvard) study was designed to characterize levels of and factors influencing personal exposures to urban air toxics among high school students living in inner-city neighborhoods of New York City and Los Angeles, California. This present article reports methods and data for the New York City phase of TEACH, focusing on the relationships between personal, indoor, and outdoor concentrations in winter and summer among a group of 46 high school students from the A. Philip Randolph Academy, a public high school located in the West Central Harlem section of New York City. Air pollutants monitored included a suite of 17 volatile organic compounds (VOCs) and aldehydes, particulate matter with a mass median aerodynamic diameter

Exposures to multiple air toxics in New York City.

PubMed

Kinney, Patrick L; Chillrud, Steven N; Ramstrom, Sonja; Ross, James; Spengler, John D

2002-08-01

Efforts to assess health risks associated with exposures to multiple urban air toxics have been hampered by the lack of exposure data for people living in urban areas. The TEACH (Toxic Exposure Assessment, a Columbia/Harvard) study was designed to characterize levels of and factors influencing personal exposures to urban air toxics among high school students living in inner-city neighborhoods of New York City and Los Angeles, California. This present article reports methods and data for the New York City phase of TEACH, focusing on the relationships between personal, indoor, and outdoor concentrations in winter and summer among a group of 46 high school students from the A. Philip Randolph Academy, a public high school located in the West Central Harlem section of New York City. Air pollutants monitored included a suite of 17 volatile organic compounds (VOCs) and aldehydes, particulate matter with a mass median aerodynamic diameter

A meiotic drive element in the maize pathogen Fusarium verticillioides is located within a 102-kb region of chromosome V

USDA-ARS?s Scientific Manuscript database

Fusarium verticillioides is an agriculturally important fungus because of its association with maize and its propensity to contaminate grain with toxic compounds. Some isolates of the fungus harbor a meiotic drive element known as Spore killer (SkK) that causes nearly all surviving meiotic progeny f...

Toxicity of selected insecticides applied to western spruce budworm

Treesearch

Jacqueline E. Robertson; Nancy L. Gillette; Barbara A. Lucas; Robert L. Lyon

1976-01-01

The contact toxlaty of 100 insecticides to last stage larvae of Choristoneura occidentalis Freeman was tested by topical application in a 10-yr series of screening experiments. Pyrethroids were generally the most toxic group of chemicals tested. Compounds more toxic than the standard, mexacarbate, at LD90 were:...

Determination of toxic and essential trace elements in serum of healthy and hypothyroid respondents by ICP-MS: A chemometric approach for discrimination of hypothyroidism.

PubMed

Stojsavljević, Aleksandar; Trifković, Jelena; Rasić-Milutinović, Zorica; Jovanović, Dragana; Bogdanović, Gradimir; Mutić, Jelena; Manojlović, Dragan

2018-07-01

Inductively coupled plasma-mass spectrometry ((ICP-MS)) was used to determine three toxic (Ni, As, Cd) and six essential trace elements (Cr, Mn, Co, Cu, Zn, Se) in blood serum of patients with hypothyroidism (Hy group) and healthy people (control group), in order to set the experimental conditions for accurate determination of a unique profile of these elements in hypothyroidism. Method validation was performed with standard reference material of the serum by varying the sample treatment with both standard and collision mode for analysis of elements isotopes. Quadratic curvilinear functions with good performances of models and the lowest detection limits were obtained for 52 Cr, 66 Zn, 75 As, 112 Cd in collision mode, and 55 Mn, 59 Co, 60 Ni, 65 Cu, 78 Se in standard mode. Treatment of serum samples with aqueous solution containing nitric acid, Triton X-100 and n-butanol gave the best results. Chemometric tools were applied for discrimination of patients with hypothyroidism. All nine elements discriminated Hy group of samples with almost the same discriminating power as indicated by their higher values for this group of patients. Statistically significant correlation (p < 0.01) was observed for several elements. Results indicated clear differences in element profile between Hy and control group and it could be used as a unique profile of hypothyroid state. Copyright © 2018 Elsevier GmbH. All rights reserved.

Ameliorative Effects of Dietary Selenium Against Cadmium Toxicity Is Related to Changes in Trace Elements in Chicken Kidneys.

PubMed

Zhang, Runxiang; Wang, Yanan; Wang, Chao; Zhao, Peng; Liu, Huo; Li, Jianhong; Bao, Jun

2017-04-01

The ameliorative effects of selenium (Se) against cadmium (Cd)-induced toxicity have been reported extensively. However, few studies have assessed the effects of multiple ions simultaneously on the variations of elements. In this study, the changes in Se, Cd, and 26 other element concentrations were investigated in chicken kidneys. One hundred and twenty-eight 31-week-old laying hens were fed a diet supplemented with either Se, Cd, or both Se and Cd for 90 days. The ion content was analyzed by inductively coupled plasma mass spectrometry (ICP-MS). We found that the Se, Cd, and combined Se and Cd treatments significantly affected the trace elements in the chicken kidneys. The Cd supplement caused ion profile disorders, including reduced concentrations of V, Cr, Mn, Mo, As, Ba, Hg, Ti, and Pb and increased Si, Cu, Li, Cd, and Sb. The Se supplement reduced the contents of Co, Mo, and Pb and increased the contents of Cr, Fe, and Se. Moreover, Se also increased the concentrations of Cr, Mn, Zn, and Se and decreased those of Li and Pb, which in contrast were induced by Cd. Complex interactions between elements were analyzed, and both positive and negative correlations among these elements are presented. The present study indicated that Se can help against the negative effects of Cd and may be related to the homeostasis of the trace elements in chicken kidneys.

Recurrence quantification analysis to characterize cyclical components of environmental elemental exposures during fetal and postnatal development

PubMed Central

Austin, Christine; Gennings, Chris; Tammimies, Kristiina; Bölte, Sven; Arora, Manish

2017-01-01

Environmental exposures to essential and toxic elements may alter health trajectories, depending on the timing, intensity, and mixture of exposures. In epidemiologic studies, these factors are typically analyzed as a function of elemental concentrations in biological matrices measured at one or more points in time. Such an approach, however, fails to account for the temporal cyclicity in the metabolism of environmental chemicals, which if perturbed may lead to adverse health outcomes. Here, we conceptualize and apply a non-linear method–recurrence quantification analysis (RQA)–to quantify cyclical components of prenatal and early postnatal exposure profiles for elements essential to normal development, including Zn, Mn, Mg, and Ca, and elements associated with deleterious health effects or narrow tolerance ranges, including Pb, As, and Cr. We found robust evidence of cyclical patterns in the metabolic profiles of nutrient elements, which we validated against randomized twin-surrogate time-series, and further found that nutrient dynamical properties differ from those of Cr, As, and Pb. Furthermore, we extended this approach to provide a novel method of quantifying dynamic interactions between two environmental exposures. To achieve this, we used cross-recurrence quantification analysis (CRQA), and found that elemental nutrient-nutrient interactions differed from those involving toxicants. These rhythmic regulatory interactions, which we characterize in two geographically distinct cohorts, have not previously been uncovered using traditional regression-based approaches, and may provide a critical unit of analysis for environmental and dietary exposures in epidemiological studies. PMID:29112980

Computational toxicology as implemented by the U.S. EPA: providing high throughput decision support tools for screening and assessing chemical exposure, hazard and risk.

PubMed

Kavlock, Robert; Dix, David

2010-02-01

Computational toxicology is the application of mathematical and computer models to help assess chemical hazards and risks to human health and the environment. Supported by advances in informatics, high-throughput screening (HTS) technologies, and systems biology, the U.S. Environmental Protection Agency EPA is developing robust and flexible computational tools that can be applied to the thousands of chemicals in commerce, and contaminant mixtures found in air, water, and hazardous-waste sites. The Office of Research and Development (ORD) Computational Toxicology Research Program (CTRP) is composed of three main elements. The largest component is the National Center for Computational Toxicology (NCCT), which was established in 2005 to coordinate research on chemical screening and prioritization, informatics, and systems modeling. The second element consists of related activities in the National Health and Environmental Effects Research Laboratory (NHEERL) and the National Exposure Research Laboratory (NERL). The third and final component consists of academic centers working on various aspects of computational toxicology and funded by the U.S. EPA Science to Achieve Results (STAR) program. Together these elements form the key components in the implementation of both the initial strategy, A Framework for a Computational Toxicology Research Program (U.S. EPA, 2003), and the newly released The U.S. Environmental Protection Agency's Strategic Plan for Evaluating the Toxicity of Chemicals (U.S. EPA, 2009a). Key intramural projects of the CTRP include digitizing legacy toxicity testing information toxicity reference database (ToxRefDB), predicting toxicity (ToxCast) and exposure (ExpoCast), and creating virtual liver (v-Liver) and virtual embryo (v-Embryo) systems models. U.S. EPA-funded STAR centers are also providing bioinformatics, computational toxicology data and models, and developmental toxicity data and models. The models and underlying data are being made publicly available through the Aggregated Computational Toxicology Resource (ACToR), the Distributed Structure-Searchable Toxicity (DSSTox) Database Network, and other U.S. EPA websites. While initially focused on improving the hazard identification process, the CTRP is placing increasing emphasis on using high-throughput bioactivity profiling data in systems modeling to support quantitative risk assessments, and in developing complementary higher throughput exposure models. This integrated approach will enable analysis of life-stage susceptibility, and understanding of the exposures, pathways, and key events by which chemicals exert their toxicity in developing systems (e.g., endocrine-related pathways). The CTRP will be a critical component in next-generation risk assessments utilizing quantitative high-throughput data and providing a much higher capacity for assessing chemical toxicity than is currently available.

Molluscicidal properties and selective toxicity of surface-active agents

PubMed Central

Visser, S. A.

1965-01-01

Of over 100 commercially produced surface-active agents tested against the bilharziasis vector snail Biomphalaria sudanica, 13 were found to possess considerable and highly selective molluscicidal properties at concentrations of less than 1 ppm for exposures of 48 hours. Against crustacea, fish, water plants, mosquito larvae, mice, and the eggs of B. sudanica, the toxicities of the 13 surfactants were slight. The chemicals did not appear to be absorbed by organic matter to any appreciable extent. It is thought that the toxicity to B. sudanica is of both a chemical and a physical nature. PMID:5294185

Behavioral toxicity of selected radioprotectors

NASA Astrophysics Data System (ADS)

Landauer, M. R.; Davis, H. D.; Kumar, K. S.; Weiss, J. F.

1992-10-01

Effective radioprotection with minimal behavioral disruption is essential for the selection of protective agents to be used in manned spaceflight. This overview summarizes the studies on the behavioral toxicity of selected radioprotectors classified as phosphorothioates (WR-2721, WR-3689), bioactive lipids (16, 16 dimethylprostaglandin E2(DiPGE2), platelet activating factor (PAF), leukotriene C4), and immunomodulators (glucan, synthetic trehalose dicorynomycolate, and interleukin-1). Behavioral toxicity was examined in laboratory mice using a locomotor activity test. For all compounds tested, there was a dose-dependent decrease in locomotor behavior that paralleled the dose-dependent increase in radioprotection. While combinations of radioprotective compounds (DiPGE2 plus WR-2721) increased radioprotection, they also decreased locomotor activity. The central nervous system stimulant, caffeine, was able to mitigate the locomotor decrement produced by WR-3689 or PAF.

Select Dietary Phytochemicals Function as Inhibitors of COX-1 but Not COX-2

PubMed Central

Li, Haitao; Zhu, Feng; Sun, Yanwen; Li, Bing; Oi, Naomi; Chen, Hanyong; Lubet, Ronald A.; Bode, Ann M.; Dong, Zigang

2013-01-01

Recent clinical trials raised concerns regarding the cardiovascular toxicity of selective cyclooxygenase-2 (COX-2) inhibitors. Many active dietary factors are reported to suppress carcinogenesis by targeting COX-2. A major question was accordingly raised: why has the lifelong use of phytochemicals that likely inhibit COX-2 presumably not been associated with adverse cardiovascular side effects. To answer this question, we selected a library of dietary-derived phytochemicals and evaluated their potential cardiovascular toxicity in human umbilical vein endothelial cells. Our data indicated that the possibility of cardiovascular toxicity of these dietary phytochemicals was low. Further mechanistic studies revealed that the actions of these phytochemicals were similar to aspirin in that they mainly inhibited COX-1 rather than COX-2, especially at low doses. PMID:24098505

Increase in accumulation of strontium-90 in the maternal skeleton during pregnancy and lactation: analysis of the Techa River data.

PubMed

Tolstykh, Evgenia I; Shagina, Natalia B; Degteva, Marina O

2014-08-01

The unique contamination of the Techa River (Southern Urals, Russia) in the 1950s by long-lived (90)Sr allows investigation of the accumulation of bone-seeking elements in humans. This study is based on information compiled at the Urals Research Center for Radiation Medicine (Chelyabinsk, Russia) over a long period of time. It includes the results of in vivo measurements of (90)Sr-body burden with a whole body counter (WBC), data on personal medical examinations and residence and family histories. Data on 185 women from two Techa riverside villages Muslyumovo and Brodokalmak were selected. The settlements differ in terms of (90)Sr diet intake (higher in Muslyumovo than in Brodokalmak) and ethnicity (residents were mainly Slavs in Brodokalmak and Turkic in Muslyumovo). Results of a total of 555 WBC measurements performed in 1974-1997 were available for the women studied; maximum measured values reached 40 kBq/body. The women from each settlement were subdivided into three groups according to their childbearing history: pregnancy and lactation occurred (1) during the period of maximal (90)Sr intake (1950-1951); (2) after the period of maximal intake and (3) before this period or women who were childless. An increase was found in accumulation of (90)Sr in maternal skeleton during pregnancy and lactation (group 1) by a factor of 1.5-2 in comparison with non-pregnant, non-lactating women. This result was found in both Muslyumovo and Brodokalmak samples. An increase in accumulation of toxic elements in pregnant/lactating women is associated with increased radiation/toxic doses and risk for the women's health.

Estuarine sediment toxicity tests on diatoms: Sensitivity comparison for three species

NASA Astrophysics Data System (ADS)

Moreno-Garrido, Ignacio; Lubián, Luis M.; Jiménez, Begoña; Soares, Amadeu M. V. M.; Blasco, Julián

2007-01-01

Experimental populations of three marine and estuarine diatoms were exposed to sediments with different levels of pollutants, collected from the Aveiro Lagoon (NW of Portugal). The species selected were Cylindrotheca closterium, Phaeodactylum tricornutum and Navicula sp. Previous experiments were designed to determine the influence of the sediment particle size distribution on growth of the species assayed. Percentage of silt-sized sediment affect to growth of the selected species in the experimental conditions: the higher percentage of silt-sized sediment, the lower growth. In any case, percentages of silt-sized sediment less than 10% did not affect growth. In general, C. closterium seems to be slightly more sensitive to the selected sediments than the other two species. Two groups of sediment samples were determined as a function of the general response of the exposed microalgal populations: three of the six samples used were more toxic than the other three. Chemical analysis of the samples was carried out in order to determine the specific cause of differences in toxicity. After a statistical analysis, concentrations of Sn, Zn, Hg, Cu and Cr (among all physico-chemical analyzed parameters), in order of importance, were the most important factors that divided the two groups of samples (more and less toxic samples). Benthic diatoms seem to be sensitive organisms in sediment toxicity tests. Toxicity data from bioassays involving microphytobentos should be taken into account when environmental risks are calculated.

Potential Influence of Selenium, Copper, Zinc and Cadmium on L-Thyroxine Substitution in Patients with Hashimoto Thyroiditis and Hypothyroidism.

PubMed

Rasic-Milutinovic, Z; Jovanovic, D; Bogdanovic, G; Trifunovic, J; Mutic, J

2017-02-01

Background: Besides genetic factors, it is known that some trace elements, as Selenium, Copper, and Zinc are essential for thyroid gland fuction and thyroid hormone metabolism. Moreover, there were some metals effect that suggested patterns associated with overt thyroid disease. Aim of study: Hashimoto thyroiditis (HT), chronic autoimune inflamation of thyroid gland with cosequtive hipothyroidism, is common disease in Serbia, and we thought it is worthwile to explore potential effects of essential and toxic metals and metalloides on thyroid function and ability to restore euthyroid status of them. Results: This cross-sectional, case-control, study investigated the status of essential elements (Selenium,Copper,and Zinc) and toxic metals and metalloides (Al, Cr, Mn, Co, As, Cd, Sb, Ba, Be, Pb and Ni) from the blood of 22 female, patients with Hashimoto thyroiditis and overt hypothyroidism, and compared it with those of 55 female healthy persons. We tried to establish the presence of any correlation between previous mentioned elements and thyroid function in hypothyroid patients and healthy participants. Conclusions: The results of our study suggested that the blood concentration of essential trace elements, especially the ratio of Copper, and Selenium may influence directly thyroid function in patients with HT and overt hypothyroidism.Thus, our findings may have implication to life-long substitution therapy in terms of l-thyroxine dose reduction. Furthermore, for the first time, our study shown potential toxic effect of Cadmium on thyroid function in HT patients, which may implicate the dose of l-thyroxine substitution. © Georg Thieme Verlag KG Stuttgart · New York.

Accumulation of cadmium, zinc, and copper by Helianthus annuus L.: impact on plant growth and uptake of nutritional elements.

PubMed

Rivelli, Anna Rita; De Maria, Susanna; Puschenreiter, Markus; Gherbin, Piergiorgio

2012-04-01

We investigated the effects on physiological response, trace elements and nutrients accumulation of sunflower plants grown in soil contaminated with: 5 mg kg(-1) of Cd; 5 and 300 mg kg(-1) of Cd and Zn, respectively; 5, 300, and 400 mg kg(-1) of Cd, Zn, and Cu, respectively. Contaminants applied did not produce large effects on growth, except in Cd-Zn-Cu treatment in which leaf area and total dry matter were reduced, by 15%. The contamination with Cd alone did not affect neither growth nor physiological parameters, despite considerable amounts of Cd accumulated in roots and older leaves, with a high bioconcentration factor from soil to plant. By adding Zn and then Cu to Cd in soil, significant were the toxic effects on chlorophyll content and water relations due to greater accumulation of trace elements in tissues, with imbalances in nutrients uptake. Highly significant was the interaction between shoot elements concentration (Cd, Zn, Cu, Fe, Mg, K, Ca) and treatments. Heavy metals concentrations in roots always exceeded those in stem and leaves, with a lower translocation from roots to shoots, suggesting a strategy of sunflower to compartmentalise the potentially toxic elements in physiologically less active parts in order to preserve younger tissues.

Influence of soil composition on the major, minor and trace metal content of Velebit biomedical plants.

PubMed

Zeiner, Michaela; Juranović Cindrić, Iva; Požgaj, Martina; Pirkl, Raimund; Šilić, Tea; Stingeder, Gerhard

2015-03-15

The use of medical herbs for the treatment of many human diseases is increasing nowadays due to their mild features and low side effects. Not only for their healing properties, but also for their nutritive value supplementation of diet with various herbs is recommended. Thus also their analysis is of rising importance. While total elemental compositions are published for many common herbs, the origin of toxic as well as beneficial elements is not yet well investigated. Thus different indigenous medicinal plants, namely Croatian spruce (Picea abies), savory (Satureja montana L.), mountain yarrow (Achillea clavennae), showy calamint (Calamintha grandiflora), micromeria (Micromeria croatica), yellow gentian (Gentiana lutea) and fir (Abies alba) together with soil samples were collected in the National Park Northern Velebit. The macro- and trace elements content, after microwave digestion, was determined by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and inductively coupled plasma mass spectroscopy (ICP-MS). The study focuses on the one hand on essential elements and on the other hand on non-essential elements which are considered as toxic for humans, covering in total Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr and Zn. Copyright © 2014 Elsevier B.V. All rights reserved.

Evaluation of Trace Elements in Potatoes (Solanum tuberosum) from a Suburban Area of Naples, Italy: The "Triangle of Death".

PubMed

Roma, Antonella De; Abete, Maria Cesarina; Brizio, Paola; Picazio, Giuseppe; Caiazzo, Marcello; D'auria, Jacopo Luigi; Esposito, Mauro

2017-07-01

Human exposure to contaminated food is a general health concern worldwide; it is necessary to evaluate food safety with respect to contaminants present in the edible parts of major food crops. This study evaluated the concentrations of 17 trace elements (As, Be, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Se, Sn, Tl, V, and Zn) from 51 potato plantations in the Campania region, inside the area known as the "Triangle of Death," with inductively coupled plasma mass spectrometry analysis. Results confirm that the potatoes collected from the suburban area of Naples contained concentrations of trace elements below the safe limits prescribed by the Food and Agriculture Organization of the United Nations and the World Health Organization. The concentrations of elements were similar to those reported for potatoes grown in other countries. Monitoring the content of toxic and potentially toxic elements is one of the most important aspects of food quality assurance. The environmental persistence of metals may result in the accumulation of significant levels of these contaminants in plants. They are absorbed to different extents, depending on their source, soil and climatic factors, plant genotype, and agrotechnical conditions, thereby entering the food chain and representing a risk to human health.

Plant growth, nutrients and potentially toxic elements in leaves of yerba mate clones in response to phosphorus in acid soils.

PubMed

Barbosa, Julierme Z; Motta, Antonio C V; Consalter, Rangel; Poggere, Giovana C; Santin, Delmar; Wendling, Ivar

2018-01-01

Native to subtropical region of South America, yerba mate is responsive to P under some conditions, but the degree of influence of genetic and soil on the growth and composition of the leaf is unknown. The aim of study was to evaluate plant growth, nutrients and potentially toxic elements in leaves of yerba mate clones in response to P application in acid soils. In greenhouse condition, two yerba mate clone seedlings were grown (210 days) in pots, each clone in a completely randomized design in factorial scheme (with and without P; four acid soils). The elemental composition of leaves and the growth of plants were determined. Phosphorus promoted plant growth, but this was not accompanied by increased P in leaf tissue in all conditions tested. The P effect on the elemental composition varied: decrease/null (N, K, Mg, Mn, Cu, Ni, B, Mo, Al, Cd); increase/null (C/N, C, Ca, Fe, V); increase/decrease/null (Zn, Ba, Pb) and; null (Cr). The soils affect the elemental composition of the leaves, especially Mn, with accumulation greater than 1000 mg kg-1. The Ba, Pb, Al and Zn in the leaves varied among clones. Yerba mate response to P was affected by edaphic and plant factors.

Seven Golden Rules for heuristic filtering of molecular formulas obtained by accurate mass spectrometry

PubMed Central

Kind, Tobias; Fiehn, Oliver

2007-01-01

Background Structure elucidation of unknown small molecules by mass spectrometry is a challenge despite advances in instrumentation. The first crucial step is to obtain correct elemental compositions. In order to automatically constrain the thousands of possible candidate structures, rules need to be developed to select the most likely and chemically correct molecular formulas. Results An algorithm for filtering molecular formulas is derived from seven heuristic rules: (1) restrictions for the number of elements, (2) LEWIS and SENIOR chemical rules, (3) isotopic patterns, (4) hydrogen/carbon ratios, (5) element ratio of nitrogen, oxygen, phosphor, and sulphur versus carbon, (6) element ratio probabilities and (7) presence of trimethylsilylated compounds. Formulas are ranked according to their isotopic patterns and subsequently constrained by presence in public chemical databases. The seven rules were developed on 68,237 existing molecular formulas and were validated in four experiments. First, 432,968 formulas covering five million PubChem database entries were checked for consistency. Only 0.6% of these compounds did not pass all rules. Next, the rules were shown to effectively reducing the complement all eight billion theoretically possible C, H, N, S, O, P-formulas up to 2000 Da to only 623 million most probable elemental compositions. Thirdly 6,000 pharmaceutical, toxic and natural compounds were selected from DrugBank, TSCA and DNP databases. The correct formulas were retrieved as top hit at 80–99% probability when assuming data acquisition with complete resolution of unique compounds and 5% absolute isotope ratio deviation and 3 ppm mass accuracy. Last, some exemplary compounds were analyzed by Fourier transform ion cyclotron resonance mass spectrometry and by gas chromatography-time of flight mass spectrometry. In each case, the correct formula was ranked as top hit when combining the seven rules with database queries. Conclusion The seven rules enable an automatic exclusion of molecular formulas which are either wrong or which contain unlikely high or low number of elements. The correct molecular formula is assigned with a probability of 98% if the formula exists in a compound database. For truly novel compounds that are not present in databases, the correct formula is found in the first three hits with a probability of 65–81%. Corresponding software and supplemental data are available for downloads from the authors' website. PMID:17389044

Trace elements in hazardous mineral fibres.

PubMed

Bloise, Andrea; Barca, Donatella; Gualtieri, Alessandro Francesco; Pollastri, Simone; Belluso, Elena

2016-09-01

Both occupational and environmental exposure to asbestos-mineral fibres can be associated with lung diseases. The pathogenic effects are related to the dimension, biopersistence and chemical composition of the fibres. In addition to the major mineral elements, mineral fibres contain trace elements and their content may play a role in fibre toxicity. To shed light on the role of trace elements in asbestos carcinogenesis, knowledge on their concentration in asbestos-mineral fibres is mandatory. It is possible that trace elements play a synergetic factor in the pathogenesis of diseases caused by the inhalation of mineral fibres. In this paper, the concentration levels of trace elements from three chrysotile samples, four amphibole asbestos samples (UICC amosite, UICC anthophyllite, UICC crocidolite and tremolite) and fibrous erionite from Jersey, Nevada (USA) were determined using inductively coupled plasma mass spectrometry (ICP-MS). For all samples, the following trace elements were measured: Li, Be, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Sb, Cs, Ba, La, Pb, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, U. Their distribution in the various mineral species is thoroughly discussed. The obtained results indicate that the amount of trace metals such as Mn, Cr, Co, Ni, Cu and Zn is higher in anthophyllite and chrysotile samples, whereas the amount of rare earth elements (REE) is higher in erionite and tremolite samples. The results of this work can be useful to the pathologists and biochemists who use asbestos minerals and fibrous erionite in-vitro studies as positive cyto- and geno-toxic standard references. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of trace element status of organic dairy cattle.

PubMed

Orjales, I; Herrero-Latorre, C; Miranda, M; Rey-Crespo, F; Rodríguez-Bermúdez, R; López-Alonso, M

2018-06-01

The present study aimed to evaluate trace mineral status of organic dairy herds in northern Spain and the sources of minerals in different types of feed. Blood samples from organic and conventional dairy cattle and feed samples from the respective farms were analysed by inductively coupled plasma mass spectrometry to determine the concentrations of the essential trace elements (cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), iodine (I), manganese (Mn), molybdenum (Mo), nickel (Ni), selenium (Se) and zinc (Zn)) and toxic trace elements (arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb)). Overall, no differences between organic and conventional farms were detected in serum concentrations of essential and toxic trace elements (except for higher concentrations of Cd on the organic farms), although a high level of inter-farm variation was detected in the organic systems, indicating that organic production greatly depends on the specific local conditions. The dietary concentrations of the essential trace elements I, Cu, Se and Zn were significantly higher in the conventional than in the organic systems, which can be attributed to the high concentration of these minerals in the concentrate feed. No differences in the concentrations of trace minerals were found in the other types of feed. Multivariate chemometric analysis was conducted to determine the contribution of different feed sources to the trace element status of the cattle. Concentrate samples were mainly associated with Co, Cu, I, Se and Zn (i.e. with the elements supplemented in this type of feed). However, pasture and grass silage were associated with soil-derived elements (As, Cr, Fe and Pb) which cattle may thus ingest during grazing.

Towards Mechanistic Understanding of Mercury Availability and Toxicity to Aquatic Primary Producers.

PubMed

Dranguet, Perrine; Flück, Rebecca; Regier, Nicole; Cosio, Claudia; Le Faucheur, Séverine; Slaveykova, Vera I

2014-11-01

The present article reviews current knowledge and recent progress on the bioavailability and toxicity of mercury to aquatic primary producers. Mercury is a ubiquitous toxic trace element of global concern. At the base of the food web, primary producers are central for mercury incorporation into the food web. Here, the emphasis is on key, but still poorly understood, processes governing the interactions between mercury species and phytoplankton, and macrophytes, two representatives of primary producers. Mass transfer to biota surface, adsorption to cell wall, internalization and release from cells, as well as underlying toxicity mechanisms of both inorganic mercury and methylmercury are discussed critically. In addition, the intracellular distribution and transformation processes, their importance for mercury toxicity, species-sensitivity differences and trophic transfer are presented. The mini-review is illustrated with examples of our own research.

Evaluation of toxicity of ‘Vatsanabha’ (Aconitum ferox, Ranunculaceae) Before and After Shodhana

PubMed Central

Deore, S.L.; Moon, K.V.; Khadabadi, S.S.; Deokate, U.A.; Baviskar, B.A.

2013-01-01

Ayurvedic preparations contain toxic elements like heavy metals and other chemicals exceeding their permissible limits. Ayurvedic method of detoxification of such products involves Shodhana. Hence, in present paper it has been decided to replace Ayurvedic Shodhana process by chemical purification method and to study the benefits and/or drawbacks of the traditional Ayurvedic Shodhana process. Crude aconite root, Ayurvedic Shodhana treated aconite root and chemical Shodhana treated aconite root samples were evaluated for toxicity and changes by animal studies and thin layer chromatography (TLC) respectively. The results of the toxicity study suggest that the modified method of Shodhana is less efficient as compared to the traditional Ayurvedic Shodhana process. TLC studies have shown that pseudoaconitine and aconitine were converted into far less toxic substances like veratroyl pseudoaconine and benzoylaconine respectively only in traditional Ayurvedic Shodhana. PMID:24023444

Evaluation of the attenuating properties of selected Greek clays for toxic inorganic elements in landfill sites.

PubMed

Mimides, T; Perraki, T

2000-05-15

Heavy metal attenuation properties of selected clay material collected from miscellaneous Greek sites is investigated and tested in the laboratory for their suitability, either as liners in hydrologically unsafe sites or as earth covers for sanitary landfill sites. Eleven potentially hazardous elements (As, Be, Cd, Cr, Cu, Hg, Ni, Pb, Se, V, and Zn) generated by a co-disposal landfill leachate have been considered. Experimental column and static equilibrium methods for the determination of dispersion and adsorption are described. Molecular diffusion dominates the migration phenomena with a velocity range between 1.3 x 10(-5) and 3.5 x 10(-4) cm/s throughout the experiments. A simple way to evaluate dispersion coefficients from breakthrough curves gave values of between 3.90 x 10(-6) and 3.5 x 10(-4) cm2/s, with a mean value of 1.5 x 10(-5). Static adsorption equilibrium studies supported by column runs showed that Freundlich (F = kCn) isotherms express in a better way the assimilative capacities of the tested clays, with k and n values ranging from 0.06 to 1.99 and 0.55 to 1.48 correspondingly. Mathematical models involving non-linear parabolic equations are involved. The experimental data, together with finite difference techniques and some physical clay characteristics, produced trilinear textural diagrams and predictive flow transport convection-dispersion breakthrough curves for a quick estimation of the attenuating properties of clays for heavy metals.

Leaching capacity of metals-metalloids and recovery of valuable materials from waste LCDs.

PubMed

Savvilotidou, Vasiliki; Hahladakis, John N; Gidarakos, Evangelos

2015-11-01

The purpose of Directive 2012/19/EU which is related to WEEE (Waste Electrical and Electronic Equipment), also known as "e-waste", is to contribute to their sustainable production and consumption that would most possibly be achieved by their recovery, recycling and reuse. Under this perspective, the present study focused on the recovery of valuable materials, metals and metalloids from LCDs (Liquid Crystal Displays). Indium (In), arsenic (As) and stibium (Sb) were selected to be examined for their Leaching Capacity (R) from waste LCDs. Indium was selected mainly due to its rarity and preciousness, As due to its high toxicity and wide use in LCDs and Sb due to its recent application as arsenic's replacement to improve the optimal clarity of a LCD screen. The experimental procedure included disassembly of screens along with removal and recovery of polarizers via thermal shock, cutting, pulverization and digestion of the shredded material and finally leaching evaluation of the aforementioned elements. Leaching tests were conducted under various temperatures, using various solid:liquid (S/L) ratios and solvents (acid mixtures), to determine the optimal conditions for obtaining the maximum leaching capacities. The examined elements exhibited different leaching behaviors, mainly due to the considerable diversity in their inherent characteristic properties. Indium demonstrated the highest recovery percentages (approximately 60%), while the recovery of As and Sb was unsuccessful, obtaining poor leaching percentages (0.16% and 0.5%, respectively). Copyright © 2015 Elsevier Ltd. All rights reserved.

Fundamental Study of the Development and Evaluation of Biodegradable Mg-Y-Ca-Zr Alloys as Novel Implant Materials

NASA Astrophysics Data System (ADS)

Da-Tren Chou

Degradable metals hold considerable promise as materials which exhibit higher mechanical properties than degradable polymers while corroding over time to alleviate complications such as stress-shielding and infection that is inherent to permanent, bioinert metallic biomaterials. Specifically, degradable magnesium (Mg) alloys have emerged as a promising alternative for orthopedic and craniofacial applications due to their positive bone remodeling behavior, good biocompatibility, and relatively high strength compared to polymers while exhibiting similar stiffness to natural bone. Increasing the strength to maintain device integrity during degradation while simultaneously controlling the rapid corrosion of Mg to reduce the risk of hydrogen gas accumulation and toxicity are ongoing paramount goals for optimizing Mg alloys for musculoskeletal applications. In order to address these goals, novel Mg-Y-Ca-Zr based alloys were developed with alloying elements judiciously selected to impart favorable properties. Processing techniques including solution heat treatment combined with hot extrusion were employed to further enhance the desired properties of the material namely, controlled corrosion, high strength and ductility, and minimal toxic response. Increasing the Y content contributed to improved corrosion resistance yielding corrosion rates similar to commercial Mg alloys. Hot extrusion was employed to reduce the grain size, thereby improving mechanical properties through the Hall-Petch relation. Extrusion yielded extremely high strength relative to other Mg alloys, values approaching that of iron-based alloys, due to the presence of Mg12YZn, a long period stacking order phase that served to impede dislocation propagation. Both as-cast and extruded Mg-Y-Ca-Zr alloys demonstrated excellent in vitro cytocompatibility eliciting high viability and proliferation of MC3T3 pre-osteoblast cells and human mesenchymal stem cells. Alloying elements Y and Zr were specifically shown to improve cell proliferation. Finally, implantation of Mg-Y-Ca-Zr based alloys into the mouse subcutaneous tissue and intramedullary cavities of fractured rat femurs resulted in a normal host response and fracture healing, without eliciting any local or systemic toxicity. Thus, the alloys investigated in this work demonstrated great potential for applications as orthopedic and craniofacial implant biomaterials, warranting additional pre-clinical safety and efficacy trials that will be conducted in the near future.

Long-term impact of sewage irrigation on soil properties and assessing risk in relation to transfer of metals to human food chain.

PubMed

Meena, Ramu; Datta, S P; Golui, Debasis; Dwivedi, B S; Meena, M C

2016-07-01

A case study was undertaken to assess the risk of sewage-irrigated soils in relation to the transfer of trace elements to rice and wheat grain. For this purpose, peri-urban agricultural lands under the Keshopur Effluent Irrigation Scheme (KEIS) of Delhi were selected. These agricultural lands have been receiving irrigation through sewage effluents since 1979. Sewage effluent, groundwater, soil, and plant (rice and wheat grain) samples were collected with GPS coordinates from this peri-urban area. Under wheat crop, sewage irrigation for four decades resulted into a significant buildup of zinc (141 %), copper (219 %), iron (514 %), nickel (75.0 %), and lead (28.1 %) in sewage-irrigated soils over adjacent tube well water-irrigated ones. Under rice crop, there was also a significant buildup of phosphorus (339 %), sulfur (130 %), zinc (287 %), copper (352 %), iron (457 %), nickel (258 %), lead (136 %), and cadmium (147 %) in sewage-irrigated soils as compared to that of tube well water-irrigated soils. The values of hazard quotient (HQ) for intake of trace toxic elements by humans through consumption of rice and wheat grain grown on these sewage-irrigated soils were well within the safe permissible limit. The variation in Zn, Ni, and Cd content in wheat grain could be explained by solubility-free ion activity model (FIAM) to the extent of 50.1, 56.8, and 37.2 %, respectively. Corresponding values for rice grain were 49.9, 41.2, and 42.7 %, respectively. As high as 36.4 % variation in As content in rice grain could be explained by solubility-FIAM model. Toxic limit of extractable Cd and As in soil for rice in relation to soil properties and human health hazard associated with consumption of rice grain by humans was established. A similar exercise was also done in respect of Cd for wheat. The conceptual framework of fixing the toxic limit of extractable metals and metalloid in soils with respect to soil properties and human health hazard under the modeling framework was established.

Bioavailability assessment of toxic metals using the technique "acid-volatile sulfide (AVS)-simultaneously extracted metals (SEM)" in marine sediments collected in Todos os Santos Bay, Brazil.

PubMed

Silva, Jucelino B; Nascimento, Rodrigo A; de Oliva, Sergio T; de Oliveira, Olívia M C; Ferreira, Sergio L C

2015-10-01

This paper reports the bioavailability of the metals (cadmium, copper, zinc, lead, and nickel) in sediment samples collected in seven stations from the São Paulo Estuary, Todos os Santos Bay, Brazil. The bioavailability was determined by employing the technique "acid-volatile sulfide (AVS) and simultaneously extracted metal (SEM)". The elements cadmium, copper, lead, and zinc were determined using differential pulse anodic stripping voltammetry (DPASV), while nickel was quantified utilizing electrothermal atomic absorption spectrometry (ET AAS). The accuracy of these methods was confirmed using a certified reference material of estuarine sediment (NIST 1646). The sulfide was quantified using potentiometry with selective electrode and the organic matter determination employing an indirect volumetric method using potassium dichromate and iron(II) sulfate solutions. The bioavailability of the metals was estimated by relationship between the concentration of AVS and the sum of the concentrations of the simultaneously extracted metals (ΣSEM), considering a significant toxicity when (ΣSEM)/(AVS) is higher than 1. The bioavailability values in the seven stations studied varied from 0.93 to 1.31 (June, 2014) and from 0.34 to 0.58 (September, 2014). These results demonstrated a critical condition of toxicity (bioavailability >1) in six of the seven sediment samples collected during the rainy season (June, 2014). In the other period (September, 2014), the bioavailability was always lower than 1 for all sediment samples collected in the seven stations. The individual values of the concentrations of the five metals were compared with the parameters PEL (probable effects level) and TEL (threshold effects level), which are commonly employed for characterization of ecological risk in environmental systems. This comparison revealed that all metals have concentrations lower than the PEL and only zinc and lead in some stations have contents higher than the TEL. The bioavailability evaluation and the concentrations achieved for the five elements in the sediments samples analyzed demonstrated that the ecosystem studied does not present an environmental risk.

Pyrrolizidine Alkaloids: Testing for Toxic Constituents of Comfrey.

ERIC Educational Resources Information Center

Vollmer, John J.; And Others

1987-01-01

Discusses the possibilities of toxins present in medicinal herbs. Describes an experiment in which toxic constituents can be selectively detected by thin-layer chromatography and NMR spectroscopy. (TW)

Two New Reference Materials Based on Tobacco Leaves: Certification for over a Dozen of Toxic and Essential Elements

PubMed Central

Samczyński, Zbigniew; Dybczyński, Rajmund S.; Polkowska-Motrenko, Halina; Chajduk, Ewelina; Pyszynska, Marta; Danko, Bożena; Czerska, Elżbieta; Kulisa, Krzysztof; Doner, Katarzyna; Kalbarczyk, Paweł

2012-01-01

The preparation, certification, and characterization of two new biological certified reference materials for inorganic trace analysis have been presented. They are based on two different varieties of tobacco leaves, namely, Oriental Basma Tobacco Leaves (INCT-OBTL-5), grown in Greece, and Polish Virginia Tobacco Leaves (INCT-PVTL-6), grown in Poland. Certification of the materials was based on the statistical evaluation of results obtained in a worldwide interlaboratory comparison, in which 87 laboratories from 18 countries participated, providing 2568 laboratory averages on nearly 80 elements. It was possible to establish the certified values of concentration for many elements in the new materials, that is, 37 in INCT-OBTL-5 and 36 in INCT-PVTL-6, including several toxic ones like As, Cd, Hg, Pb, and so forth. The share and the role of instrumental analytical techniques used in the process of certification of the new CRMs are discussed. PMID:22536124

Investigating different mechanisms for biogenic selenite transformations: Geobacter sulfurreducens, Shewanella oneidensis and Veillonella atypica

USGS Publications Warehouse

Pearce, C.I.; Pattrick, R.A.D.; Law, N.; Charnock, J.M.; Coker, V.S.; Fellowes, J.W.; Oremland, R.S.; Lloyd, J.R.

2009-01-01

The metal-reducing bacteria Geobacter sulfurreducens, Shewanella oneidensis and Veillonella atypica, use different mechanisms to transform toxic, bioavailable sodium selenite to less toxic, non-mobile elemental selenium and then to selenide in anaerobic environments, offering the potential for in situ and ex situ bioremediation of contaminated soils, sediments, industrial effluents, and agricultural drainage waters. The products of these reductive transformations depend on both the organism involved and the reduction conditions employed, in terms of electron donor and exogenous extracellular redox mediator. The intermediary phase involves the precipitation of elemental selenium nanospheres and the potential role of proteins in the formation of these structures is discussed. The bionanomineral phases produced during these transformations, including both elemental selenium nanospheres and metal selenide nanoparticles, have catalytic, semiconducting and light-emitting properties, which may have unique applications in the realm of nanophotonics. This research offers the potential to combine remediation of contaminants with the development of environmentally friendly manufacturing pathways for novel bionanominerals. ?? 2009 Taylor & Francis.

GEMAS - Soil geochemistry and health implications

NASA Astrophysics Data System (ADS)

Ernstsen, Vibeke; Ladenberger, Anna; Wragg, Joanna; Gulan, Aleksandra

2014-05-01

The GEMAS Project resulted in a large coherent data set displaying baseline levels of elements in agricultural and grazing land soil, which has a wide variety of applications. Medical geology is an emerging new discipline providing a link between geoscience and medicine by interpreting natural geological factors in relation to human and animal health and their geographical distribution. Medical geology shows not only problems related to harmful health effects of natural geological materials and processes, but also deals with their beneficial aspects. Since the GEMAS project demonstrates the importance of geological factors in geochemical patterns in European soil, this data set can be used in improving our understanding of how the geological processes may affect human health in Europe. The main potential health problems are related to deficiency of nutrients in soil and toxic effects of potentially harmful elements. Deficiency in macro- (e.g., K, Fe, Mg, P) and micro-nutrients (e.g., Se, Zn, Cl) can be responsible for a reduction in crop productivity and certain health issues for livestock and humans. On the other hand, bioavailability of crucial elements depends on soil parameters, e.g., pH; namely, low pH in soil (in northern Europe) makes more micronutrients bioavailable, with the exception of Mo, P and Ca. Rocks underlying the soil layer have a major impact on soil composition, and soil parent material can be a main source of toxic metals, for instance, soil developed on black shale (e.g., Oslo region) shows potentially toxic levels of metals, such as As, Cd, U, Zn and Pb. High content of organic matter is another factor amplifying the toxic levels of metals in soil. Several important topics with health implications can be then addressed using the GEMAS data set, namely, soil properties and element bioavailability, arsenic toxicity, selenium deficiency, potential health effects of liming, uranium in European soil, influence of recent and historical volcanic activity on soil composition and its health consequences. References Reimann, C., Birke, M., Demetriades, A., Filzmoser, P. & O'Connor, P. (Editors), 2014. Chemistry of Europe's agricultural soils - Part A: Methodology and interpretation of the GEMAS data set. Geologisches Jahrbuch (Reihe B), Schweizerbarth, Hannover, 528 pp. Reimann, C., Birke, M., Demetriades, A., Filzmoser, P. & O'Connor, P. (Editors), 2014. Chemistry of Europe's agricultural soils - Part B: General background information and further analysis of the GEMAS data set. Geologisches Jahrbuch (Reihe B), Schweizerbarth, Hannover, 352 pp.

Toxicity and biodegradability of selected N-substituted phenols under anaerobic conditions

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

Donlon, B.; Razo-Flores, E.; Hwu, C.S.

1995-12-31

The anaerobic toxicity and biodegradability of N-substituted aromatics were evaluated in order to obtain information on their ultimate biotreatment. The toxicity of selected N-substituted aromatic compounds toward acetoclastic methanogens in granular sludge was measured in batch assays. This toxicity was highly correlated with compound hydrophobicity, indicating that partitioning into the bacterial membranes was an important factor in the toxicity. However, other factors, such as chemical interactions with key cell components, were suggested to be playing an important role. Nitroaromatic compounds were, on the average, over 300-fold more toxic than their amino-substituted counterparts. This finding suggests that the facile reduction ofmore » nitro-groups known to occur in anaerobic environments would result in a high level of detoxification. To test this hypothesis, continuous lab-scale upward-flow anaerobic sludge bed reactors treating 2-nitrophenol and 4-nitrophenol were established. The 4-nitrophenol was readily converted to the corresponding 4-aminophenol, whereas complete mineralization of 2-nitrophenol via intermediate formation of 2-aminophenol was obtained. These conversions led to a dramatic detoxification of the nitrophenols, because it was feasible to treat the highly toxic nitrophenolics at high organic loading rates.« less

Human Exposure and Health Effects of Inorganic and Elemental Mercury

PubMed Central

Zheng, Wei

2012-01-01

Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety. PMID:23230464

Trace elements distributions at Datoko-Shega artisanal mining site, northern Ghana.

PubMed

Arhin, Emmanuel; Boansi, Apea Ohene; Zango, M S

2016-02-01

Environmental geochemistry classifies elements into essential, non-essential and toxic elements in relationship to human health. To assess the environmental impact of mining at Datoko-Shega area, the distributions and concentrations of trace elements in stream sediments and soil samples were carried out. X-ray fluorescence analytical technique was used to measure the major and trace element concentrations in sediments and modified fire assay absorption spectrometry in soils. The results showed general depletion of major elements except titanium oxide (TiO2) compared to the average crustal concentrations. The retention of TiO2 at the near surface environment probably was due to the intense tropical weathering accompanied by the removal of fine sediments and soil fractions during the harmattan season by the dry north-east trade winds and sheet wash deposits formed after flash floods. The results also showed extreme contamination of selenium (Se), cadmium (Cd) and mercury (Hg), plus strong contaminations of arsenic (As) and chromium (Cr) in addition to moderate contamination of lead (Pb) in the trace element samples relative to crustal averages in the upper continental crust. However Hg, Pb and Cd concentrations tend to be high around the artisanal workings. It was recognised from the analysis of the results that the artisanal mining activity harnessed and introduces some potentially toxic elements such as Hg, Cd and Pb mostly in the artisan mine sites. But the interpretation of the trace element data thus invalidates the elevation of As concentrations to be from the mine operations. It consequently noticed As values in the mine-impacted areas to be similar or sometimes lower than As values in areas outside the mine sites from the stream sediment results.

Human exposure and health effects of inorganic and elemental mercury.

PubMed

Park, Jung-Duck; Zheng, Wei

2012-11-01

Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety.

Phytoaccumulation of trace elements by wetland plants: 3. Uptake and accumulation of ten trace elements by twelve plant species

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

Qian, J.H.; Zayed, A.; Zhu, Y.L.

1999-10-01

Interest is increasing in using wetland plants in constructed wetlands to remove toxic elements from polluted wastewater. To identify those wetland plants that hyperaccumulate trace elements, 12 plant species were tested for their efficiency to bioconcentrate 10 potentially toxic trace elements including As, b, Cd, Cr, Cu, Pb, Mn, Hg, Ni, and Se. Individual plants were grown under carefully controlled conditions and supplied with 1 mg L{sup {minus}1} of each trace element individually for 10 d. Except B, all elements accumulated to much higher concentrations in roots than in shoots. Highest shoot tissue concentrations (mg kg{sup {minus}1} DW) of themore » various trace elements were attained by the following species: umbrella plant (Cyperus alternifolius L.) for Mn (198) and Cr (44); water zinnia (Wedelia trilobata Hitchc.) for Cd (148) and Ni (80); smartweed (Polygonum hydropiperoides Michx.) for Cu (95) and Pb (64); water lettuce (Pistia stratiotes L.) for Hg (92), As (34), and Se (39); and mare's tail (hippuris vulgaris L.) for B (1132). Whereas, the following species attained the highest root tissue concentrations (mg kg{sup {minus}1} DW); stripped rush (Baumia rubiginosa) for Mn (1683); parrot's feather (Myriophyllum brasiliense Camb.) for Cd (1426) and Ni (1077); water lettuce for Cu (1038), Hg (1217), and As (177); smartweed for Cr (2980) and Pb (1882); mare's tail for B (1277); and monkey flower (Mimulus guttatus Fisch.) for Se (384). From a phytoremediation perspective, smartweed was probably the best plant species for trace element removal from wastewater due to its faster growth and higher plant density.« less

[ELEMENTAL STATUS OF PATIENTS WITH VARIOUS FORMS OF VITILIGO].

PubMed

Tsiskarishvili, N I; Katsitadze, A; Tsiskarishvili, N V; Charischarishvili, I

2017-12-01

Vitiligo is a multifactorial disease in which, in each specific case of its manifestation, different mechanisms of its pathogenesis and different levels of melanin formation in the skin can be involved. Skin is one of the most metabolically active organs. Carrying out a number of vital functions (barrier, protective, respiratory, excretory, metabolic, immune, etc.), it needs microelementss. Of the 92 naturally occurring chemical elements, 81 are found in the human body. Lack of the vital elements, leads to the emergence of diseases, which are based on deficiency, excess or imbalance of micro- and macroelements in the body. To assess the elemental status of patients with various forms of vitiligo, fluorescent x-ray spectroscopy was used. The method has good informativeness, since the hair most fully reflects the level of content of both toxic and vital elements. According to the results obtained, in patients with segmental vitiligo, a slight decrease in the content of manganese and copper was detected in the hair. In the group of patients with non-segmental form of vitiligo, along with a significant decrease in the concentration of basic elements (on average from 20 to 50%) copper, manganese, selenium, zinc, there was an increase in the indices of such toxic elements as lead and cadmium. The data of multi-element hair analysis, as are confirmed by well-known information about the role of certain chemical elements in the pathogenesis of vitiligo, also allow us to make new assumptions about the possible relationship between the violation of the microelement balance of the organism with the emergence and peculiarity of the flow of various forms of vitiligo. The correct approach to understanding the mechanisms of the emergence of vitiligo, will allow to offer new effective schemes for the treatment of vitiligo.

Exploiting Nutritional Value of Staple Foods in the World’s Semi-Arid Areas: Risks, Benefits, Challenges and Opportunities of Sorghum

PubMed Central

Proietti, Ilaria; Frazzoli, Chiara; Mantovani, Alberto

2015-01-01

Sorghum (Sorghum bicolor (L.) Moench) is a drought-resistant crop and an important food resource in terms of nutritional as well as social-economic values, especially in semi-arid environments. Cultivar selection and processing methods have been observed to impact on composition and functional and nutritional value of sorghum. Amino acid imbalance, cyanogenic glycosides, endogenous anti-nutrients, mycotoxins and toxic elements are among factors impairing its nutritional value. This paper reviews possible approaches (varieties selection, production practices, cooking processes) to improve the benefits-to-risks balance of sorghum meal, to mitigate the risk of deficiencies and/or imbalances and to improve effects on human nutrition. Opportunity for avoiding dietary diversification in high sorghum consumers is also discussed, e.g., tryptophan and niacin deficits potentially related to pellagra, or unavailability of proteins and divalent cations (e.g., Fe, Zn) due to the antinutrient activity of phytic acid and tannins. As potential candidate for production investments, the role of sorghum in preserving biological diversity is also considered. PMID:27417755

Exploiting Nutritional Value of Staple Foods in the World's Semi-Arid Areas: Risks, Benefits, Challenges and Opportunities of Sorghum.

PubMed

Proietti, Ilaria; Frazzoli, Chiara; Mantovani, Alberto

2015-03-30

Sorghum (Sorghum bicolor (L.) Moench) is a drought-resistant crop and an important food resource in terms of nutritional as well as social-economic values, especially in semi-arid environments. Cultivar selection and processing methods have been observed to impact on composition and functional and nutritional value of sorghum. Amino acid imbalance, cyanogenic glycosides, endogenous anti-nutrients, mycotoxins and toxic elements are among factors impairing its nutritional value. This paper reviews possible approaches (varieties selection, production practices, cooking processes) to improve the benefits-to-risks balance of sorghum meal, to mitigate the risk of deficiencies and/or imbalances and to improve effects on human nutrition. Opportunity for avoiding dietary diversification in high sorghum consumers is also discussed, e.g., tryptophan and niacin deficits potentially related to pellagra, or unavailability of proteins and divalent cations (e.g., Fe, Zn) due to the antinutrient activity of phytic acid and tannins. As potential candidate for production investments, the role of sorghum in preserving biological diversity is also considered.

The development of Army relevant peptide-based surface enhanced Raman scattering (SERS) sensors for biological threat detection

NASA Astrophysics Data System (ADS)

Farrell, Mikella E.; Strobbia, Pietro; Sarkes, Deborah A.; Stratis-Cullum, Dimitra N.; Cullum, Brian M.; Pellegrino, Paul M.

2016-05-01

The utility of peptide-based molecular sensing for the development of novel biosensors has resulted in a significant increase in their development and usage for sensing targets like chemical, biological, energetic and toxic materials. Using peptides as a molecular recognition element is particularly advantageous because there are several mature peptide synthesis protocols that already exist, peptide structures can be tailored, selected and manipulated to be highly discerning towards desired targets, peptides can be modified to be very stable in a host of environments and stable under many different conditions, and through the development of bifunctionalized peptides can be synthesized to also bind onto desired sensing platforms (various metal materials, glass, etc.). Two examples of the several Army relevant biological targets for peptide-based sensing platforms include Ricin and Abrin. Ricin and Abrin are alarming threats because both can be weaponized and there is no antidote for exposure. Combining the sensitivity of SERS with the selectivity of a bifunctional peptide allows for the emergence of dynamic hazard sensor for Army application.

Process and catalyst for carbonylating olefins

DOEpatents

Zoeller, Joseph Robert

1998-06-02

Disclosed is an improved catalyst system and process for preparing aliphatic carbonyl compounds such as aliphatic carboxylic acids, alkyl esters of aliphatic carboxylic acids and anhydrides of aliphatic carboxylic acids by carbonylating olefins in the presence of a catalyst system comprising (1) a first component selected from at least one Group 6 metal, i.e., chromium, molybdenum, and/or tungsten and (2) a second component selected from at least one of certain halides and tertiary and quaternary compounds of a Group 15 element, i.e., nitrogen, phosphorus and/or arsenic, and (3) as a third component, a polar, aprotic solvent. The process employing the improved catalyst system is carried out under carbonylating conditions of pressure and temperature discussed herein. The process constitutes and improvement over known processes since it can be carried out at moderate carbonylation conditions without the necessity of using an expensive noble metal catalyst, volatile, toxic materials such as nickel tetracarbonyl, formic acid or a formate ester. Further, the addition of a polar, aprotic solvent to the catalyst system significantly increases, or accelerates, the rate at which the carbonylation takes place.

Assessment of biotic response to heavy metal contamination in Avicennia marina mangrove ecosystems in Sydney Estuary, Australia.

PubMed

Nath, Bibhash; Chaudhuri, Punarbasu; Birch, Gavin

2014-09-01

Mangrove forests act as a natural filter of land-derived wastewaters along industrialized tropical and sub-tropical coastlines and assist in maintaining a healthy living condition for marine ecosystems. Currently, these intertidal communities are under serious threat from heavy metal contamination induced by human activity associated with rapid urbanization and industrialization. Studies on the biotic responses of these plants to heavy metal contamination are of great significance in estuary management and maintaining coastal ecosystem health. The main objective of the present investigation was to assess the biotic response in Avicennia marina ecosystems to heavy metal contamination through the determination of metal concentrations in leaves, fine nutritive roots and underlying sediments collected in fifteen locations across Sydney Estuary (Australia). Metal concentrations (especially Cu, Pb and Zn) in the underlying sediments of A. marina were enriched to a level (based on Interim Sediment Quality Guidelines) at which adverse biological effects to flora could occasionally occur. Metals accumulated in fine nutritive roots greater than underlying sediments, however, only minor translocation of these metals to A. marina leaves was observed (mean translocation factors, TFs, for all elements <0.13, except for Mn). Translocation factors of essential elements (i.e., common plant micro-nutrients, Cu, Ni, Mn and Zn) were greater than non-essential elements (As, Cd, Co, Cr and Pb), suggesting that A. marina mangroves of this estuary selectively excluded non-essential elements, while regulating essential elements and limiting toxicity to plants. This study supports the notion that A. marina mangroves act as a phytostabilizer in this highly modified estuary thereby protecting the aquatic ecosystem from point or non-point sources of heavy metal contamination. Copyright © 2014 Elsevier Inc. All rights reserved.

Remote Excavation of Heavily Contaminated UXO Sites. The Range Master

DTIC Science & Technology

2007-09-05

NUMBER 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 6. AUTHOR(S) 7. PERFORMING ORGANIZATION NAME(S) AND...Master) ESTCP Project UX-200327 ii Final Phase II Report, September 2007 3.5.5 Sampling Plan...Explosive HSP Health and Safety Program HTRW Hazardous, Toxic, and Radioactive Waste HTW Hazardous and Toxic Waste HW Hazardous Waste IAW In

Hepatic concentrations of copper and other metals in dogs with and without chronic hepatitis.

PubMed

Cedeño, Y; López-Alonso, M; Miranda, M

2016-12-01

Defects in copper metabolism have been described in several dog breeds, and recently, it has been suggested that changes in other essential trace elements could be involved in the pathogenesis of hepatic disease. This study measured hepatic copper accumulation and its interactions with other essential trace and toxic metals in dogs diagnosed with chronic hepatitis. Liver samples of 20 chronic hepatitis and 20 healthy dogs were collected. Samples were acid digested, and essential metals (cobalt, copper, iron, manganese, molibdenum, selenium and zinc) and toxic metals (arsenic, cadmium, mercury and lead) were analysed by inductively-coupled plasma mass spectrometry. Copper concentrations were significantly higher in dogs affected by hepatic disease than in controls. Dogs having chronic hepatitis with liver copper concentration greater than 100 mg/kg wet weight showed statistically higher cobalt, manganese and zinc concentrations than dogs having chronic hepatitis with liver copper concentrations less than 100 mg/kg wet weight and controls. Toxic metal concentrations were low - in all cases below the threshold associated with toxicity in dogs. Dogs with chronic hepatitis not only have increased concentrations of copper in the liver but also increased concentrations of cobalt, manganese and zinc; measurement of these elements may perhaps aid in diagnosis of liver disease in dogs. © 2016 British Small Animal Veterinary Association.

Fumigant toxicity of basil oil compounds and related compounds to Thrips palmi and Orius strigicollis.

PubMed

Kim, Kwang-Ho; Yi, Chang-Geun; Ahn, Young-Joon; Kim, Soon Il; Lee, Sang-Guei; Kim, Jun-Ran

2015-09-01

This study was aimed at assessing the fumigant toxicity to adult Thrips palmi (a serious insect pest) and Orius strigicollis (a beneficial predator insect) of basil (Ocimum basilicum) essential oil compounds and structurally related compounds using vapour-phase toxicity bioassays. Against adult T. palmi, linalool (LD50 0.0055 mg cm(-3) ) was the most toxic fumigant and was 15.2-fold more effective than dichlorvos (0.0837 mg cm(-3) ). Strong fumigant toxicity was also observed in pulegone (0.0095 mg cm(-3) ), (±)-camphor (0.0097 mg cm(-3) ) and 1,8-cineole (0.0167 mg cm(-3) ). Moderate toxicity was produced by camphene, 3-carene, (-)-menthone, (+)-α-pinene, (+)-β-pinene, α-terpineol and (-)-α-thujone (0.0215-0.0388 mg cm(-3) ). Against adult O. strigicollis, dichlorvos (LD50 9.0 × 10(-10) mg cm(-3) ) was the most toxic fumigant, whereas the LD50 values of these compounds ranged from 0.0127 to >0.23 mg cm(-3) . Based upon the selective toxicity ratio, the compounds described are more selective than dichlorvos. The basil oil compounds described merit further study as potential insecticides for control of T. palmi in greenhouses because of their generally lower toxicity to O. strigicollis and their greater activity as a fumigant than dichlorvos. © 2014 Society of Chemical Industry.

Macrophage-selective toxicity as a mechanism of hydroquinone-induced myelotoxicity

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

Thomas, D.J.

1989-01-01

This research has focused upon the role of the bone marrow stroma in the etiology of benzene hematotoxicity. Treatment with the metabolite hydroquinone results in a reduced capacity of the stroma to support myelopoiesis. The goal of this research was to examine stromal cell selective toxicity following hydroquinone treatment. Populations of macrophages and a fibroblastoid cell line (LTF) or primary fibroblasts were developed from mouse bone marrow. Following treatment of with hydroquinone, treated or control fibroblastoid cells were reconstituted with control or treated macrophages, respectively, and the cultures were assayed for their ability to support myelopoiesis. To examine mechanisms ofmore » selective toxicity, macrophage and LTF cultures were incubated with 14C-hydroquinone and bioactivation was examined. After 24 hours, macrophages had 16-fold higher levels of bound {sup 14}C than LTF cells. Peroxide-dependent bioactivation in cell homogenates revealed that peroxide could support formation of covalent-binding species in macrophage homogenates but not in LTF homogenates. It was determined that macrophages, but not LTF cells, contained detectable levels of peroxidase activity which was consistent with the postulate that increased binding was due to peroxidase-mediated bioactivation of hydroquinone. Accordingly, purified myeloperoxidase incubated with {sup 14}C-hydroquinone, resulted in bioactivation to a covalent-binding species. This study provided evidence supporting selective bioactivation as a mechanism of selective toxicity of hydroquinone to bone marrow stromal macrophages.« less

High levels of heavy metal accumulation in dental calculus of smokers: a pilot inductively coupled plasma mass spectrometry study.

PubMed

Yaprak, E; Yolcubal, I; Sinanoğlu, A; Doğrul-Demiray, A; Guzeldemir-Akcakanat, E; Marakoğlu, I

2017-02-01

Various trace elements, including toxic heavy metals, may exist in dental calculus. However, the effect of environmental factors on heavy metal composition of dental calculus is unknown. Smoking is a major environmental source for chronic toxic heavy metal exposition. The aim of this study is to compare toxic heavy metal accumulation levels in supragingival dental calculus of smokers and non-smokers. A total of 29 supragingival dental calculus samples were obtained from non-smoker (n = 14) and smoker (n = 15) individuals. Subjects with a probability of occupational exposure were excluded from the study. Samples were analyzed by inductively coupled plasma mass spectrometry in terms of 26 metals and metalloids, including toxic heavy metals. Toxic heavy metals, arsenic (p < 0.05), cadmium (p < 0.05), lead (p < 0.01), manganese (p < 0.01) and vanadium (p < 0.01) levels were significantly higher in smokers than non-smokers. The levels of other examined elements were similar in both groups (p > 0.05). Within the limitations of this study, it can be concluded that the elementary composition of dental calculus may be affected by environmental factors such as tobacco smoke. Therefore, dental calculus may be utilized as a non-invasive diagnostic biological material for monitoring chronic oral heavy metal exposition. However, further studies are required to evaluate its diagnostic potential. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Nitrite Biosensing via Selective Enzymes—A Long but Promising Route

PubMed Central

Almeida, M. Gabriela; Serra, Alexandra; Silveira, Celia M.; Moura, Jose J.G.

2010-01-01

The last decades have witnessed a steady increase of the social and political awareness for the need of monitoring and controlling environmental and industrial processes. In the case of nitrite ion, due to its potential toxicity for human health, the European Union has recently implemented a number of rules to restrict its level in drinking waters and food products. Although several analytical protocols have been proposed for nitrite quantification, none of them enable a reliable and quick analysis of complex samples. An alternative approach relies on the construction of biosensing devices using stable enzymes, with both high activity and specificity for nitrite. In this paper we review the current state-of-the-art in the field of electrochemical and optical biosensors using nitrite reducing enzymes as biorecognition elements and discuss the opportunities and challenges in this emerging market. PMID:22163541

Bioavailability and risk assessment of potentially toxic elements in garden edible vegetables and soils around a highly contaminated former mining area in Germany.

PubMed

Antoniadis, Vasileios; Shaheen, Sabry M; Boersch, Judith; Frohne, Tina; Du Laing, Gijs; Rinklebe, Jörg

2017-01-15

Although soil contamination by potentially toxic elements (PTEs) in Europe has a history of many centuries, related problems are often considered as having been dealt with due to the enforcement of tight legislations. However, there are many unsolved issues. We aimed to assess PTE levels in highly contaminated soils and in garden edible vegetables using human health risk indices in order to evaluate the availability and mobilization of arsenic (As), copper (Cu), manganese (Mn), mercury (Hg), lead (Pb), and zinc (Zn). In four gardens in Germany, situated on, or in the vicinity of, a mine dump area, we planted beans (Phaseolus vulgaris ssp. nanus), carrots (Daucus sativus) and lettuce (Lactuca sativa ssp. capitata). We examined soil-to-plant mobilization of elements using transfer coefficient (TC), as well as soil contamination using contamination factor (CF), enrichment factor (EF), and bioaccumulation index (I geo ). In addition, we tested two human health risk assessment indices: Soil-induced hazard quotient (HQ S ) (representing the "direct soil ingestion" pathway), and vegetable-induced hazard quotient (HQ V ) (representing the "vegetable intake" pathway). The studied elements were highly elevated in the soils. The values in garden 2 were especially high (e.g., Pb: 13789.0 and Hg: 36.8 mg kg -1 ) and largely exceeded the reported regulation limits of 50 (for As), 40 (Cu), 400 (Pb), 150 (Zn), and 5 (Hg) mg kg -1 . Similarly, element concentrations were very high in the grown vegetables. The indices of CF, EF and I geo were enhanced even to levels that are rarely reported in the literature. Specifically, garden 2 indicated severe contamination due to multi-element deposition. The contribution of each PTE to the total of measured HQ S revealed that Pb was the single most important element causing health risk (contributing up to 77% to total HQ S ). Lead also posed the highest risk concerning vegetable consumption, contributing up to 77% to total HQ V . The presence of lead in both cases was followed by that of As, Mn and Hg. We conclude that in multi-element contamination cases, along with high-toxicity elements (here, Pb, As and Hg) other elements may also be responsible for increasing human health risks (i.e., Mn), due to the possibility of adverse synergism of the PTEs. Copyright © 2016. Published by Elsevier Ltd.

DISTRIBUTED STRUCTURE-SEARCHABLE TOXICITY ...

EPA Pesticide Factsheets

The ability to assess the potential genotoxicity, carcinogenicity, or other toxicity of pharmaceutical or industrial chemicals based on chemical structure information is a highly coveted and shared goal of varied academic, commercial, and government regulatory groups. These diverse interests often employ different approaches and have different criteria and use for toxicity assessments, but they share a need for unrestricted access to existing public toxicity data linked with chemical structure information. Currently, there exists no central repository of toxicity information, commercial or public, that adequately meets the data requirements for flexible analogue searching, SAR model development, or building of chemical relational databases (CRD). The Distributed Structure-Searchable Toxicity (DSSTox) Public Database Network is being proposed as a community-supported, web-based effort to address these shared needs of the SAR and toxicology communities. The DSSTox project has the following major elements: 1) to adopt and encourage the use of a common standard file format (SDF) for public toxicity databases that includes chemical structure, text and property information, and that can easily be imported into available CRD applications; 2) to implement a distributed source approach, managed by a DSSTox Central Website, that will enable decentralized, free public access to structure-toxicity data files, and that will effectively link knowledgeable toxicity data s

Lethal and sublethal effects of selected insecticides and an insect growth regulator on the boll weevil (Coleoptera: Curculionidae) ectoparasitoid Catolaccus grandis (Hymenoptera: Pteromalidae).

PubMed

Elzen, G W; Maldonado, S N; Rojas, M G

2000-04-01

A laboratory culture of Catolaccus grandis (Burks), an ectoparasitoid of the boll weevil, Anthonomus grandis grandis Boheman, was exposed to lethal and sublethal doses of insecticides and an insect growth regulator using a spray chamber bioassay. Materials tested were azinphos-methyl, endosulfan, fipronil, malathion, cyfluthrin, dimethoate, spinosad, methyl parathion, acephate, oxamyl, and tebufenozide. At full rates, spinosad was significantly less toxic to female C. grandis than other treatments except endosulfan. Fipronil and malathion were significantly more toxic to females than other treatments. Most of the chemicals tested were highly toxic to male C. grandis; spinosad was least toxic. At reduced rates, most of 4 selected chemicals tested were low in toxicity to C. grandis; however, a reduced rate of malathion was significantly more toxic to females than other treatments. No C. grandis pupae developed from parasitism during a 24-h treatment period with malathion or spinosad. The sex ratio of progeny from sprayed adults appeared to be unaffected by the treatments.

Health effects and toxicity mechanisms of rare earth elements-Knowledge gaps and research prospects.

PubMed

Pagano, Giovanni; Guida, Marco; Tommasi, Franca; Oral, Rahime

2015-05-01

In the recent decades, rare earth elements (REE) have undergone a steady spread in several industrial and medical applications, and in agriculture. Relatively scarce information has been acquired to date on REE-associated biological effects, from studies of bioaccumulation and of bioassays on animal, plant and models; a few case reports have focused on human health effects following occupational REE exposures, in the present lack of epidemiological studies of occupationally exposed groups. The literature is mostly confined to reports on few REE, namely cerium and lanthanum, whereas substantial information gaps persist on the health effects of other REE. An established action mechanism in REE-associated health effects relates to modulating oxidative stress, analogous to the recognized redox mechanisms observed for other transition elements. Adverse outcomes of REE exposures include a number of endpoints, such as growth inhibition, cytogenetic effects, and organ-specific toxicity. An apparent controversy regarding REE-associated health effects relates to opposed data pointing to either favorable or adverse effects of REE exposures. Several studies have demonstrated that REE, like a number of other xenobiotics, follow hormetic concentration-related trends, implying stimulatory or protective effects at low levels, then adverse effects at higher concentrations. Another major role for REE-associated effects should be focused on pH-dependent REE speciation and hence toxicity. Few reports have demonstrated that environmental acidification enhances REE toxicity; these data may assume particular relevance in REE-polluted acidic soils and in REE mining areas characterized by concomitant REE and acid pollution. The likely environmental threats arising from REE exposures deserve a new line of research efforts. Copyright © 2015 Elsevier Inc. All rights reserved.

Use of porewater extracts to identify the cause of toxicity in marine and estuarine sediments

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

Douglas, W.S.

1994-12-31

Amphipod toxicity tests in the evaluation of dredged material proposed for ocean disposal has come under increased scrutiny by the regulated community in the Port of NY/NJ. In recent large-scale assessments of sediment quality in the harbor, the vast majority of locations were deemed highly contaminated when tested with Ampelisca abdita. Toxicity tests, by themselves, do not provide data regarding the cause of toxicity of these sediments. The enormous potential costs associated with most proposed alternatives to ocean disposal of dredged sediments has prompted the investigation of the causative agents of toxicity in sediments of the NY/NJ Harbor. Sediment frommore » five locations in the harbor, selected in consultation with local regulatory agencies to represent diverse potential contamination scenarios, was collected and tested for toxicity to the amphipods Ampelisca abdita, Leptocheirus plumulosus, Eohaustorius estuadus, Rhepoxynius abronius, and the mysid shrimp, Mysidopsis bahia, using 10-day static bioassays. Porewater from each of the five sediments was extracted under centrifugation and used in water-only toxicity tests with A. abdita, L. plumulosus, R. abronius, E. estuadus, M. bahia, M. beryllina, and Microtox. A Phase 1 Toxicity Identification Evaluation of the three most toxic porewater samples was conducted using several of the species tested. Results from the preliminary investigations and the ongoing TIE`s will be presented. Species selection, porewater toxicity test procedures, and Phase 1, 2, and 3 paradigms will be discussed.« less

Molecular characterization and identification of markers for toxic and non-toxic varieties of Jatropha curcas L. using RAPD, AFLP and SSR markers.

PubMed

Sudheer Pamidimarri, D V N; Singh, Sweta; Mastan, Shaik G; Patel, Jalpa; Reddy, Muppala P

2009-07-01

Jatropha curcas L., a multipurpose shrub has acquired significant economic importance for its seed oil which can be converted to biodiesel, is emerging as an alternative to petro-diesel. The deoiled seed cake remains after oil extraction is toxic and cannot be used as a feed despite having best nutritional contents. No quantitative and qualitative differences were observed between toxic and non-toxic varieties of J. curcas except for phorbol esters content. Development of molecular marker will enable to differentiate non-toxic from toxic variety in a mixed population and also help in improvement of the species through marker assisted breeding programs. The present investigation was undertaken to characterize the toxic and non-toxic varieties at molecular level and to develop PCR based molecular markers for distinguishing non-toxic from toxic or vice versa. The polymorphic markers were successfully identified specific to non-toxic and toxic variety using RAPD and AFLP techniques. Totally 371 RAPD, 1,442 AFLP markers were analyzed and 56 (15.09%) RAPD, 238 (16.49%) AFLP markers were found specific to either of the varieties. Genetic similarity between non-toxic and toxic verity was found to be 0.92 by RAPD and 0.90 by AFLP fingerprinting. In the present study out of 12 microsatellite markers analyzed, seven markers were found polymorphic. Among these seven, jcms21 showed homozygous allele in the toxic variety. The study demonstrated that both RAPD and AFLP techniques were equally competitive in identifying polymorphic markers and differentiating both the varieties of J. curcas. Polymorphism of SSR markers prevailed between the varieties of J. curcas. These RAPD and AFLP identified markers will help in selective cultivation of specific variety and along with SSRs these markers can be exploited for further improvement of the species through breeding and Marker Assisted Selection (MAS).

Nanoscale zero-valent iron-assisted soil washing for the removal of potentially toxic elements.

PubMed

Boente, C; Sierra, C; Martínez-Blanco, D; Menéndez-Aguado, J M; Gallego, J R

2018-05-15

The present study focuses on soil washing enhancement via soil pretreatment with nanoscale zero-valent iron (nZVI) for the remediation of potentially toxic elements. To this end, soil polluted with As, Cu, Hg, Pb and Sb was partitioned into various grain sizes (500-2000, 125-500 and <125 μm). The fractions were pretreated with nZVI and subsequently subjected, according to grain size, to Wet-High Intensity Magnetic Separation (WHIMS) or hydrocycloning. The results were compared with those obtained in the absence of nanoparticles. An exhaustive characterization of the magnetic signal of the nanoparticles was done. This provided valuable information regarding potentially toxic elements (PTEs) fate, and allowed a metallurgical accounting correction considering the dilution effects caused by nanoparticle addition. As a result, remarkable recovery yields were obtained for Cu, Pb and Sb, which concentrated with the nZVI in the magnetically separated fraction (WHIMS tests) and underflow (hydrocyclone tests). In contrast, Hg, concentrated in the non-magnetic fraction and overflow respectively, while the behavior of As was unaltered by the nZVI pretreatment. All things considered, the addition of nZVI enhanced the efficiency of soil washing, particularly for larger fractions (125-2000 μm). The proposed methodology lays the foundations for nanoparticle utilization in soil washing operations. Copyright © 2018 Elsevier B.V. All rights reserved.

Subcellular Mn compartation, anatomic and biochemical changes of two grape varieties in response to excess manganese.

PubMed

Yao, Yinan; Xu, Gang; Mou, Dongling; Wang, Junru; Ma, Jinbiao

2012-09-01

To explore the underlying mechanism for the high tolerance to excess manganese stress in the grape species (Vitis vinifera Linn), we observed the subcellular compartment of Mn element, anatomic and biochemical responses of two grape cultivars (Combier and Shuijin) under excess Mn stress in semi-controlled environmental condition. Grape species exhibited typical detoxifying or tolerant mechanism as following: first, majority of Mn element accumulated in leaf was excluded into cell wall or comparted into cell vacuole to avoid cellular Mn-toxicity; Mn and other elements were also secreted into leaf surface or deposited in vascular wall; second, only small amount of Mn was located in cellular organ, and excess Mn in chloroplast was detoxified by depositing in starch granule, which serve as a novel detoxifying strategy; additionally, the cellular Mn was further chelated by phytochelatins; third, to quench the toxic oxygen radicals, the total phenolic compounds and polyamine (putrescine and spermidine) were enhanced. Although the obvious symptom of Mn-toxicity was not detected, we observed the dessication symptom under high level of Mn treatment in the two cultivars, such as sunk stomata, thickened palisade tissue, enhanced palisade/spongy tissue ratio and abscisic acid concentration. The growth inhibition and dessication symptom in the two grape cultivars could be largely associated with osmotic stress resulted from high concentration of leaf Mn. Copyright © 2012 Elsevier Ltd. All rights reserved.

Determination of the Mineral Composition and Toxic Element Contents of Propolis by Near Infrared Spectroscopy

PubMed Central

González-Martín, M. Inmaculada; Escuredo, Olga; Revilla, Isabel; Vivar-Quintana, Ana M.; Coello, M. Carmen; Palacios Riocerezo, Carlos; Wells Moncada, Guillermo

2015-01-01

The potential of near infrared spectroscopy (NIR) with remote reflectance fiber-optic probes for determining the mineral composition of propolis was evaluated. This technology allows direct measurements without prior sample treatment. Ninety one samples of propolis were collected in Chile (Bio-Bio region) and Spain (Castilla-León and Galicia regions). The minerals measured were aluminum, calcium, iron, potassium, magnesium, phosphorus, and some potentially toxic trace elements such as zinc, chromium, nickel, copper and lead. The modified partial least squares (MPLS) regression method was used to develop the NIR calibration model. The determination coefficient (R2) and root mean square error of prediction (RMSEP) obtained for aluminum (0.79, 53), calcium (0.83, 94), iron (0.69, 134) potassium (0.95, 117), magnesium (0.70, 99), phosphorus (0.94, 24) zinc (0.87, 10) chromium (0.48, 0.6) nickel (0.52, 0.7) copper (0.64, 0.9) and lead (0.70, 2) in ppm. The results demonstrated that the capacity for prediction can be considered good for wide ranges of potassium, phosphorus and zinc concentrations, and acceptable for aluminum, calcium, magnesium, iron and lead. This indicated that the NIR method is comparable to chemical methods. The method is of interest in the rapid prediction of potentially toxic elements in propolis before consumption. PMID:26540058

Micro-PIXE studies of Lupinus angustifolius L. after treatment of seeds with molybdenum

NASA Astrophysics Data System (ADS)

Przybylowicz, W. J.; Mesjasz-Przybylowicz, J.; Wouters, K.; Vlassak, K.; Combrink, N. J. J.

1997-02-01

An example of nuclear microprobe application in agriculture is presented. The NAC nuclear microprobe was used to determine quantitative elemental distribution of major, minor and trace elements in Lupinus angustifolius L. (Leguminosae) after treatment of seeds with molybdenum. Experiments were performed in order to establish safe concentration levels and sources of Mo in seed treatments. Elemental distributions in Mo-treated plants and in the non-treated control plants were studied in order to explain how Mo causes toxicity. Some specific regions of Mo and other main and trace elements enrichment were identified.

Iron Sulfide Attenuates the Methanogenic Toxicity of Elemental Copper and Zinc Oxide Nanoparticles and their Soluble Metal Ion Analogs

PubMed Central

Gonzalez-Estrella, Jorge; Gallagher, Sara; Sierra-Alvarez, Reyes; Field, Jim A.

2016-01-01

Elemental copper (Cu0) and zinc oxide (ZnO) nanoparticle (NP) toxicity to methanogens has been attributed to the release of soluble metal ions. Iron sulfide (FeS) partially controls the soluble concentration of heavy metals and their toxicity in aquatic environments. Heavy metals displace the Fe from FeS forming poorly soluble metal sulfides in the FeS matrix. Therefore, FeS may be expected to attenuate the NP toxicity. This work assessed FeS as an attenuator of the methanogenic toxicity of Cu0 and ZnO NPs and their soluble salt analogs. The toxicity attenuation capacity of fine (25–75 µm) and coarse (500 to 1200 µm) preparations of FeS (FeS-f and FeS-c respectively) was tested in the presence of highly inhibitory concentrations of CuCl2, ZnCl2 Cu0 and ZnO NPs. FeS-f attenuated methanogenic toxicity better than FeS-c. The results revealed that 2.5× less FeS-f than FeS-c was required to recover the methanogenic activity to 50% (activity normalized to uninhibited controls). The results also indicated that a molar FeS-f/Cu0 NP, FeS-f/ZnO NP, FeS-f/ZnCl2, and FeS-f/CuCl2 ratio of 2.14, 2.14, 4.28, and 8.56 respectively, was necessary to recover the methanogenic activity to >75%. Displacement experiments demonstrated that CuCl2 and ZnCl2 partially displaced Fe from FeS. As a whole, the results indicate that not all the sulfide in FeS was readily available to react with the soluble Cu and Zn ions which may explain the need for a large stoichiometric excesses of FeS to highly attenuate Cu and Zn toxicity. Overall, this study provides evidence that FeS attenuates the toxicity caused by Cu0 and ZnO NPs and their soluble ion analogs to methanogens. PMID:26803736

Genome wide association mapping of grain arsenic, copper, molybdenum, and zinc in rice (Oryza sativa L.) grown at four international field sites

USDA-ARS?s Scientific Manuscript database

The mineral concentrations in cereals are important for human health, especially for individuals who consume a cereal subsistence diet. A number of elements, such as zinc, are required within the diet, while some elements are toxic to humans, for example arsenic. In this study we carried out genome-...

Primary Teeth and Hair as Indicators of Environmental Pollution.

PubMed

Shishniashvili, T E; Suladze, N N; Margvelashvili, V V

2016-01-01

To study the influence of environmental pollution on the mineralization of dental hard tissues by using biosubstrates: teeth and hair. : At the first stage epidemiological survey was conducted in polluted and less polluted areas of Tbilisi (Georgia). We studied 525 children aged 3 and 4 years. Caries prevalence and intensity was defined by the methodology of World Health Organization. At the second stage the chemical elements content was studied in hair and teeth hard tissues of 24 children by X-ray fluorescent spectroscopy method. The prevalence of dental caries in the polluted region was 46%, caries intensity--1.92 (± 2.842). In the less polluted region prevalence was 37%, caries intensity--1.47 (± 2.571). These data are statistically reliable (p < 0.05). The study of hair and tooth tissues showed that the toxic elements (Pb, Hg, Sn, Ti) content in these tissues was higher in environmentally unfavorable than in favorable conditions. Hair and dental tissues can be used as indicators of environmental pollution. Our survey showed that toxic elements content in dental hard tissues was higher and the level of essential elements was less in polluted than in less polluted areas of Tbilisi.

[The effect of alternating administration of aluminum chloride and sodium fluoride in drinking water on the concentration of fluoride in serum and its content in bones of rats].

PubMed

Lubkowska, Anna; Chlubek, Dariusz; Machoy-Mokrzyniska, Anna

2006-01-01

Fluorine and aluminum remain a very interesting research topic due to equivocal and relatively unknown toxic action, role in the etiology of various diseases, and interactions of both elements. Fluorine and aluminum compounds are absorbed by organisms through the gastric and respiratory systems, although the latter route operates only at very high concentrations in air. Chronic exposure to fluorine and aluminum leads to accumulation of both elements, especially in bones and teeth, but also in lung, brain, kidney, and liver. Organisms excrete these elements with urine, faeces, and to a minor extent with sweat and bile. In the light of reports suggesting that aluminum has protective properties against fluorine toxicity during exposure to both elements, we decided to examine the effect of alternating doses of aluminum fluoride and sodium fluoride in drinking water on rats. Four female groups received: I--100 ppm fluorine ions during one month; II--100 ppm fluorine ions alternating every two days with 300 ppm aluminum ions during one month; III--100 ppm fluoride ions during four months; IV--100 ppm fluorine ions alternating every two days with 300 ppm aluminum ions during four months. The respective male groups called IA, IIA, IIIA, and IVA were treated identically. Subsequently, the animals were anesthetized and sacrificed. Blood was sampled from the heart and the right femur was removed for fluorine determination. Fluorine content in the femur and serum was determined with an ion-selective electrode (Orion). The results were analyzed statistically (Statistica 6). We observed higher fluoride concentrations in serum as compared with control values in all groups of female and male rats exposed to sodium fluoride only. Longer exposure time (4 months) did not result in further increase in serum fluoride concentration. However, longer exposure increased fluoride accumulation in the femur (p < 0.001). All groups exposed to NaF had significantly higher fluoride concentration in the femur as compared with control animals. Groups receiving NaF and AlCl3 showed lower fluoride concentration in serum and femur compared with those exposed to NaF only and higher in comparison with controls. Fluorine content in the femur of rats exposed to NaF and AlCI3 for four months was similar to the results obtained after one month of exposure.

Comparison of cytotoxicity and expression of metal regulatory genes in zebrafish (Danio rerio) liver cells exposed to cadmium sulfate, zinc sulfate and quantum dots.

PubMed

Tang, Song; Allagadda, Vinay; Chibli, Hicham; Nadeau, Jay L; Mayer, Gregory D

2013-10-01

Recent advances in the ability to manufacture and manipulate materials at the nanometer scale have led to increased production and use of many types of nanoparticles. Quantum dots (QDs) are small, fluorescent nanoparticles composed of a core of semiconductor material (e.g. cadmium selenide, zinc sulfide) and shells or dopants of other elements. Particle core composition, size, shell, and surface chemistry have all been found to influence toxicity in cells. The aim of this study was to compare the toxicities of ionic cadmium (Cd) and zinc (Zn) and Cd- and Zn-containing QDs in zebrafish liver cells (ZFL). As expected, Cd(2+) was more toxic than Zn(2+), and the general trend of IC50-24 h values of QDs was determined to be CdTe < CdSe/ZnS or InP/ZnS, suggesting that ZnS-shelled CdSe/ZnS QDs were more cytocompatible than bare core CdTe crystals. Smaller QDs showed greater toxicity than larger QDs. Isolated mRNA from these exposures was used to measure the expression of metal response genes including metallothionein (MT), metal response element-binding transcription factor (MTF-1), divalent metal transporter (DMT-1), zrt and irt like protein (ZIP-1) and the zinc transporter, ZnT-1. CdTe exposure induced expression of these genes in a dose dependent manner similar to that of CdSO4 exposure. However, CdSe/ZnS and InP/ZnS altered gene expression of metal homeostasis genes in a manner different from that of the corresponding Cd or Zn salts. This implies that ZnS shells reduce QD toxicity attributed to the release of Cd(2+), but do not eliminate toxic effects caused by the nanoparticles themselves.

The Molecular Basis of Toxins’ Interactions with Intracellular Signaling via Discrete Portals

PubMed Central

Lahiani, Adi; Yavin, Ephraim; Lazarovici, Philip

2017-01-01

An understanding of the molecular mechanisms by which microbial, plant or animal-secreted toxins exert their action provides the most important element for assessment of human health risks and opens new insights into therapies addressing a plethora of pathologies, ranging from neurological disorders to cancer, using toxinomimetic agents. Recently, molecular and cellular biology dissecting tools have provided a wealth of information on the action of these diverse toxins, yet, an integrated framework to explain their selective toxicity is still lacking. In this review, specific examples of different toxins are emphasized to illustrate the fundamental mechanisms of toxicity at different biochemical, molecular and cellular- levels with particular consideration for the nervous system. The target of primary action has been highlighted and operationally classified into 13 sub-categories. Selected examples of toxins were assigned to each target category, denominated as portal, and the modulation of the different portal’s signaling was featured. The first portal encompasses the plasma membrane lipid domains, which give rise to pores when challenged for example with pardaxin, a fish toxin, or is subject to degradation when enzymes of lipid metabolism such as phospholipases A2 (PLA2) or phospholipase C (PLC) act upon it. Several major portals consist of ion channels, pumps, transporters and ligand gated ionotropic receptors which many toxins act on, disturbing the intracellular ion homeostasis. Another group of portals consists of G-protein-coupled and tyrosine kinase receptors that, upon interaction with discrete toxins, alter second messengers towards pathological levels. Lastly, subcellular organelles such as mitochondria, nucleus, protein- and RNA-synthesis machineries, cytoskeletal networks and exocytic vesicles are also portals targeted and deregulated by other diverse group of toxins. A fundamental concept can be drawn from these seemingly different toxins with respect to the site of action and the secondary messengers and signaling cascades they trigger in the host. While the interaction with the initial portal is largely determined by the chemical nature of the toxin, once inside the cell, several ubiquitous second messengers and protein kinases/ phosphatases pathways are impaired, to attain toxicity. Therefore, toxins represent one of the most promising natural molecules for developing novel therapeutics that selectively target the major cellular portals involved in human physiology and diseases. PMID:28300784

Toxicity of plant essential oils to different life stages of the poultry red mite, Dermanyssus gallinae, and non-target invertebrates.

PubMed

George, D R; Sparagano, O A E; Port, G; Okello, E; Shiel, R S; Guy, J H

2010-03-01

Seven essential oils with potential as acaricides for use against the poultry red mite, Dermanyssus gallinae (De Geer) (Acari: Dermanyssidae), were selected for study. These products (essential oils of manuka, cade, pennyroyal, thyme, garlic, clove bud and cinnamon bark) were deployed against different life stages of D. gallinae in laboratory tests at the (lethal concentration) LC(50) level for adult mites. For all essential oils tested, toxicity to D. gallinae juveniles was as high as toxicity to adults, if not higher. However, at the LC(50) level determined for adults, some oils were ineffective in preventing hatching of D. gallinae eggs. The essential oils were also tested under laboratory conditions at their LC(90) levels for D. gallinae adults on two model non-target species, the brine shrimp, Artemia salina (L.), and the mealworm beetle, Tenebrio molitor (L.). Results showed that not all essential oils were as toxic to A. salina and T. molitor as they were to D. gallinae, suggesting that it may be possible to select certain oils for development as acaricides against D. gallinae that would have minimal impact on non-target organisms. However, the level of toxicity to A. salina and T. molitor was not consistent across the selected essential oils.

Patient- and therapy-related factors associated with the incidence of xerostomia in nasopharyngeal carcinoma patients receiving parotid-sparing helical tomotherapy.

PubMed

Lee, Tsair-Fwu; Liou, Ming-Hsiang; Ting, Hui-Min; Chang, Liyun; Lee, Hsiao-Yi; Wan Leung, Stephen; Huang, Chih-Jen; Chao, Pei-Ju

2015-08-20

We investigated the incidence of moderate to severe patient-reported xerostomia among nasopharyngeal carcinoma (NPC) patients treated with helical tomotherapy (HT) and identified patient- and therapy-related factors associated with acute and chronic xerostomia toxicity. The least absolute shrinkage and selection operator (LASSO) normal tissue complication probability (NTCP) models were developed using quality-of-life questionnaire datasets from 67 patients with NPC. For acute toxicity, the dosimetric factors of the mean doses to the ipsilateral submandibular gland (Dis) and the contralateral submandibular gland (Dcs) were selected as the first two significant predictors. For chronic toxicity, four predictive factors were selected: age, mean dose to the oral cavity (Doc), education, and T stage. The substantial sparing data can be used to avoid xerostomia toxicity. We suggest that the tolerance values corresponded to a 20% incidence of complications (TD20) for Dis = 39.0 Gy, Dcs = 38.4 Gy, and Doc = 32.5 Gy, respectively, when mean doses to the parotid glands met the QUANTEC 25 Gy sparing guidelines. To avoid patient-reported xerostomia toxicity, the mean doses to the parotid gland, submandibular gland, and oral cavity have to meet the sparing tolerance, although there is also a need to take inherent patient characteristics into consideration.

Toxic hydrogen sulfide and dark caves: life-history adaptations in a livebearing fish (Poecilia mexicana, Poeciliidae).

PubMed

Riesch, Rüdiger; Plath, Martin; Schlupp, Ingo

2010-05-01

Life-history traits are very sensitive to extreme environmental conditions, because resources that need to be invested in somatic maintenance cannot be invested in reproduction. Here we examined female life-history traits in the Mexican livebearing fish Poecilia mexicana from a variety of benign surface habitats, a creek with naturally occurring toxic hydrogen sulfide (H2S), a sulfidic cave, and a non-sulfidic cave. Previous studies revealed pronounced genetic and morphological divergence over very small geographic scales in this system despite the absence of physical barriers, suggesting that local adaptation to different combinations of two selection factors, toxicity (H2S) and darkness, is accompanied by very low rates of gene flow. Hence, we investigated life-history divergence between these populations in response to the selective pressures of darkness and/or toxicity. Our main results show that toxicity and darkness both select for (or impose constraints on) the same female trait dynamics: reduced fecundity and increased offspring size. Since reduced fecundity in the sulfur cave population was previously shown to be heritable, we discuss how divergent life-history evolution may promote further ecological divergence: for example, reduced fecundity and increased offspring autonomy are clearly beneficial in extreme environments, but fish with these traits are outcompeted in benign habitats.

Analysis of metal-binding proteins separated by non-denaturating gel electrophoresis using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS).

PubMed

Becker, J Susanne; Mounicou, Sandra; Zoriy, Miroslav V; Becker, J Sabine; Lobinski, Ryszard

2008-09-15

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) have become established as very efficient and sensitive biopolymer and elemental mass spectrometric techniques for studying metal-binding proteins (metalloproteins) in life sciences. Protein complexes present in rat tissues (liver and kidney) were separated in their native state in the first dimension by blue native gel electrophoresis (BN-PAGE). Essential and toxic metals, such as zinc, copper, iron, nickel, chromium, cadmium and lead, were detected by scanning the gel bands using quadrupole LA-ICP-MS with and without collision cell as a microanalytical technique. Several proteins were identified by using MALDI-TOF-MS together with a database search. For example, on one protein band cut from the BN-PAGE gel and digested with the enzyme trypsin, two different proteins - protein FAM44B and cathepsin B precursor - were identified. By combining biomolecular and elemental mass spectrometry, it was possible to characterize and identify selected metal-binding rat liver and kidney tissue proteins.

Aspects of a Distinct Cytotoxicity of Selenium Salts and Organic Selenides in Living Cells with Possible Implications for Drug Design.

PubMed

Estevam, Ethiene Castellucci; Witek, Karolina; Faulstich, Lisa; Nasim, Muhammad Jawad; Latacz, Gniewomir; Domínguez-Álvarez, Enrique; Kieć-Kononowicz, Katarzyna; Demasi, Marilene; Handzlik, Jadwiga; Jacob, Claus

2015-07-31

Selenium is traditionally considered as an antioxidant element and selenium compounds are often discussed in the context of chemoprevention and therapy. Recent studies, however, have revealed a rather more colorful and diverse biological action of selenium-based compounds, including the modulation of the intracellular redox homeostasis and an often selective interference with regulatory cellular pathways. Our basic activity and mode of action studies with simple selenium and tellurium salts in different strains of Staphylococcus aureus (MRSA) and Saccharomyces cerevisiae indicate that such compounds are sometimes not particularly toxic on their own, yet enhance the antibacterial potential of known antibiotics, possibly via the bioreductive formation of insoluble elemental deposits. Whilst the selenium and tellurium compounds tested do not necessarily act via the generation of Reactive Oxygen Species (ROS), they seem to interfere with various cellular pathways, including a possible inhibition of the proteasome and hindrance of DNA repair. Here, organic selenides are considerably more active compared to simple salts. The interference of selenium (and tellurium) compounds with multiple targets could provide new avenues for the development of effective antibiotic and anticancer agents which may go well beyond the traditional notion of selenium as a simple antioxidant.

Rapid and selective adsorption of cationic dyes by a unique metal-organic framework with decorated pore surface

NASA Astrophysics Data System (ADS)

Zhang, Jie; Li, Fan; Sun, Qian

2018-05-01

Organic dye pollutants become a big headache due to their toxic nature to the environment, and it should be one of the best solutions if we can remove and separate them. Here, a metal-organic framework (MOF) (denoted as Zn-MOF) with carbonyl group based on fluorenone-2,7-dicarboxylate ligand, was directly synthesized without post-synthesis method and applied to selectively absorb cationic dyes such as MB, CV, RhB from aqueous solution, while anionic or neutral dyes were excluded. Characterization of the Zn-MOF was achieved by X-ray diffraction, scanning electron microscope, Fourier transform infrared spectrometry and elemental analysis. The Zn-MOF mainly possesses open pore channels, high surface area, big pore volume, and most important, the pore surface is furnished with carbonyl groups arising from the ligand and pointing toward the centers of the large chambers of the framework, which are benefit for the adsorption of the cationic dyes. The MB maximum adsorption capacities can attain 326 mg g-1, which is probably due to the suitable pore size, higher solvent-accessible void, and the prominent adsorption capacity of the mesoporous material. The dye adsorption process for the material is proven to be charge-selective and size-selective, and the adsorption isotherms, as well as kinetics characteristic of dye adsorption onto the Zn-MOF were also investigated.

Effects of SiC nanoparticles orally administered in a rat model: Biodistribution, toxicity and elemental composition changes in feces and organs

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

Lozano, Omar, E-mail: omar.lozanogarcia@fundp.ac.be; Research Centre for the Physics of Matter and Radiation; Laloy, Julie

2012-10-15

Background: Silicon carbide (SiC) presents noteworthy properties as a material such as high hardness, thermal stability, and photoluminescent properties as a nanocrystal. However, there are very few studies in regard to the toxicological potential of SiC NPs. Objectives: To study the toxicity and biodistribution of silicon carbide (SiC) nanoparticles in an in vivo rat model after acute (24 h) and subacute (28 days) oral administrations. The acute doses were 0.5, 5, 50, 300 and 600 mg·kg{sup −1}, while the subacute doses were 0.5 and 50 mg·kg{sup −1}. Results: SiC biodistribution and elemental composition of feces and organs (liver, kidneys, andmore » spleen) have been studied by Particle-Induced X-ray Emission (PIXE). SiC and other elements in feces excretion increased by the end of the subacute assessment. SiC did not accumulate in organs but some elemental composition modifications were observed after the acute assessment. Histopathological sections from organs (stomach, intestines, liver, and kidneys) indicate the absence of damage at all applied doses, in both assessments. A decrease in the concentration of urea in blood was found in the 50 mg·kg{sup −1} group from the subacute assessment. No alterations in the urine parameters (sodium, potassium, osmolarity) were found. Conclusion: This is the first study that assesses the toxicity, biodistribution, and composition changes in feces and organs of SiC nanoparticles in an in vivo rat model. SiC was excreted mostly in feces and low traces were retrieved in urine, indicating that SiC can cross the intestinal barrier. No sign of toxicity was however found after oral administration. -- Highlights: ► SiC nanoparticles were orally administered to rats in acute and subacute doses. ► SiC was found in low traces in urine. It is mostly excreted in feces within 5 days. ► SiC excretion rate, feces and organ elemental composition change with time. ► No morphological alteration were found on GI tract, liver, kidneys, or spleen. ► Urea increased in blood in the subacute assessment. No change in urine properties.« less

Decaleside: a new class of natural insecticide targeting tarsal gustatory sites

NASA Astrophysics Data System (ADS)

Rajashekar, Yallappa; Rao, Lingamallu J. M.; Shivanandappa, Thimmappa

2012-10-01

Natural sources for novel insecticide molecules hold promise in view of their eco-friendly nature, selectivity, and mammalian safety. Recent progress in understanding the biology of insect olfaction and taste offers new strategies for developing selective pest control agents. We have isolated two natural insecticidal molecules from edible roots of Decalepis hamiltonii named Decalesides I and II, which are novel trisaccharides, highly toxic to household insect pests and stored-product insects. We have experimentally shown that insecticidal activity requires contact with tarsi on the legs but is not toxic orally. The insecticidal activity of molecules is lost by hydrolysis, and various sugars modify toxic response, showing that the insecticidal activity is via gustatory sites on the tarsi. Selective toxicity to insects by virtue of their gustatory site of action and the mammalian safety of the new insecticides is inherent in their chemical structure with 1-4 or 1-1 α linkage that is easily hydrolyzed by digestive enzymes of mammals. Decalesides represent a new chemical class of natural insecticides with a unique mode of action targeting tarsal chemosensory/gustatory system of insects.

Toxicity of new pyrethroid in pest insects Asciamonuste and Diaphania hyalinata, predator Solenopsis saevissima and stingless bee Tetragonisca angustula.

PubMed

Moreno, Shaiene C; Silvério, Flaviano O; Lopes, Mayara C; Ramos, Rodrigo S; Alvarenga, Elson S; Picanço, Marcelo C

2017-04-03

There is increasing demand for new products for vegetable pest management. Thus, the aim of this study was to assess the toxicity of pyrethroids with acid moiety modifications to measure the insecticidal activity of these compounds on the lepidopteran vegetable pests Diaphania hyalinata (L.) (Lepidoptera: Pyralidae) and Asciamonuste (Latreille) (Lepidoptera: Pieridae) and evaluate their selectivity for the predatory ant Solenopsis saevissima (F. Smith) (Hymenoptera: Formicidae) and pollinator Tetragonisca angustula (Latreille) (Hymenoptera: Apidae: Meliponinae). Racemic mixtures of five new pyrethroids (30 µg molecule mg -1 insect body weight) resulted in high (100%) and rapid (stable LD 50 after 12 h) mortality in D. hyalinata and A. monuste. In A. monuste, the trans-pyrethroid [12] isomer showed similar toxicity to permethrin. For D. hyalinata, the trans-pyrethroid [9] isomer and cis-pyrethroid [10] isomer were as toxic as permethrin. Due to their low selectivity, these new pyrethroids should be applied on the basis of ecological selectivity principles to minimize impacts on nontarget organisms S. saevissima and T. angustula.

Informed Consent Conversations and Documents: A Quantitative Comparison

PubMed Central

Koyfman, Shlomo A.; Reddy, Chandana A.; Hizlan, Sabahat; Leek, Angela C.; Kodish, Eric

2015-01-01

Background Informed consent for clinical research includes two components: informed consent documents (ICD) and informed consent conversations (ICC). Readability software has been used to help simplify the language of the ICD, but rarely employed to assess the language during the ICC, which may influence the quality of informed consent. This analysis was completed to determine if length and reading levels of transcribed ICCs are lower than their corresponding ICDs for selected clinical trials, and to assess whether investigator experience affected use of simpler language and comprehensiveness. Methods Prospective study where ICCs were audio-recorded at 6 institutions when families were offered participation in pediatric phase I oncology trials. Word count, Flesch-Kincaid Grade Level (FKGL) and Flesch Reading Ease Score (FRES) of ICCs were compared to corresponding ICDs, including the frequency that investigators addressed 8 pre-specified critical consent elements during the ICC. Results Sixty-nine unique physician/protocol pairs were identified. Overall, ICCs contained fewer words (4,677 vs. 6,364; p=0.0016), had lower FKGL (6 vs. 9.7; p=<0.0001) and higher FRES (77.8 vs. 56.7; p<0.0001) than their respective ICDs, but were more likely to omit critical consent elements, such as voluntariness (55%) and dose limiting toxicities (26%). Years of investigator experience was not correlated with reliably covering critical elements or decreased linguistic complexity. Conclusions Clinicians use more understandable language during ICCs than the corresponding ICD, but less reliably cover elements critical to fully informed consent. Focused efforts at providing communication training for clinician-investigators should be done to optimize the synergy between the ICD and conversation. PMID:26505269

The use of olive-mill waste compost to promote the plant vegetation cover in a trace-element-contaminated soil.

PubMed

Pardo, Tania; Martínez-Fernández, Domingo; Clemente, Rafael; Walker, David J; Bernal, M Pilar

2014-01-01

The applicability of a mature compost as a soil amendment to promote the growth of native species for the phytorestoration of a mine-affected soil from a semi-arid area (SE Spain), contaminated with trace elements (As, Cd, Cu, Mn, Pb and Zn), was evaluated in a 2-year field experiment. The effects of an inorganic fertiliser were also determined for comparison. Bituminaria bituminosa was the selected native plant since it is a leguminous species adapted to the particular local pedoclimatic conditions. Compost addition increased total organic-C concentrations in soil with respect to the control and fertiliser treatments, maintained elevated available P concentrations throughout the duration of the experiment and stimulated soil microbial biomass, while trace elements extractability in the soil was rather low due to the calcareous nature of the soil and almost unaltered in the different treatments. Tissue concentrations of P and K in B. bituminosa increased after the addition of compost, associated with growth stimulation. Leaf Cu concentration was also increased by the amendments, although overall the trace elements concentrations can be considered non-toxic. In addition, the spontaneous colonisation of the plots by a total of 29 species of 15 different families at the end of the experiment produced a greater vegetation cover, especially in plots amended with compost. Therefore, the use of compost as a soil amendment appears to be useful for the promotion of a vegetation cover and the phytostabilisation of moderately contaminated soils under semi-arid conditions.

A chemical status predictor. A methodology based on World-Wide sediment samples.

PubMed

Gredilla, A; Fdez-Ortiz de Vallejuelo, S; de Diego, A; Arana, G; Stoichev, T; Amigo, J M; Wasserman, J C; Botello, A V; Sarkar, S K; Schäfer, J; Moreno, C; Guardia, M de la; Madariaga, J M

2015-09-15

As a consequence of the limited resources of underdeveloped countries and the limited interest of the developed ones, the assessment of the chemical quality of entire water bodies around the world is a utopia in the near future. The methodology described here may serve as a first approach for the fast identification of water bodies that do not meet the good chemical status demanded by the European Water Framework Directive (WFD). It also allows estimating the natural background (or reference values of concentration) of the areas under study using a simple criterion. The starting point is the calculation the World-Wide Natural Background Levels (WWNBLs) and World-Wide Threshold Values (WWTVs), two indexes that depend on the concentration of seven elements present in sediments. These elements, As, Cd, Cr, Cu, Ni, Pb and Zn, have been selected taking into account the recommendations of the UNEP (United Nations Environment Programme) and USEPA (United States Environmental Protection Agency), that describe them as elements of concern with respect to environmental toxicity. The methodology has been exemplified in a case study that includes 134 sediment samples collected in 11 transitional water bodies from 7 different countries and 4 different continents. Six of the water bodies considered met the good chemical status demanded by the WFD. The rest of them exceeded the reference WWTVs, at least for one of the elements. The estuaries of the Nerbioi-Ibaizabal (Basque Country) and Cavado (Portugal), the sea inlet of Río San Pedro (Spain), the Sepetiba Bay (Brazil) and the Yucateco lagoon (Mexico) belong to that group. Copyright © 2015 Elsevier Ltd. All rights reserved.

Environmental hazard of oil shale combustion fly ash.

PubMed

Blinova, Irina; Bityukova, Liidia; Kasemets, Kaja; Ivask, Angela; Käkinen, Aleksandr; Kurvet, Imbi; Bondarenko, Olesja; Kanarbik, Liina; Sihtmäe, Mariliis; Aruoja, Villem; Schvede, Hedi; Kahru, Anne

2012-08-30

The combined chemical and ecotoxicological characterization of oil shale combustion fly ash was performed. Ash was sampled from the most distant point of the ash-separation systems of the Balti and Eesti Thermal Power Plants in North-Eastern Estonia. The fly ash proved potentially hazardous for tested aquatic organisms and high alkalinity of the leachates (pH>10) is apparently the key factor determining its toxicity. The leachates were not genotoxic in the Ames assay. Also, the analysis showed that despite long-term intensive oil-shale combustion accompanied by considerable fly ash emissions has not led to significant soil contamination by hazardous trace elements in North-Eastern Estonia. Comparative study of the fly ash originating from the 'new' circulating fluidized bed (CFB) combustion technology and the 'old' pulverized-fired (PF) one showed that CFB fly ash was less toxic than PF fly ash. Thus, complete transfer to the 'new' technology will reduce (i) atmospheric emission of hazardous trace elements and (ii) fly ash toxicity to aquatic organisms as compared with the 'old' technology. Copyright © 2012 Elsevier B.V. All rights reserved.