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Despite their high persistence in the environment, organochlorines (OC) are widely used in the pharmaceutical industry, in plastics, and in the manufacture of pesticides, among other applications. These compounds and the byproducts of their decomposition deserve attention and efficient proposals for their treatment. Among sustainable alternatives, the use of ligninolytic enzymes (LEs) from fungi stands out, as these molecules can catalyze the transformation of a wide range of pollutants. Among LEs, laccases (Lac) are known for their efficiency as biocatalysts in the conversion of organic pollutants. Their application in biotechnological processes is possible, but the enzymes are often unstable and difficult to recover after use, driving up costs. Immobilization of enzymes on a matrix (support or solid carrier) allows recovery and stabilization of this catalytic capacity. Agricultural residual biomass is a passive environmental asset. Although underestimated and still treated as an undesirable component, residual biomass can be used as a low‐cost adsorbent and as a support for the immobilization of enzymes. In this review, the adsorption capacity and immobilization of fungal Lac on supports made from residual biomass, including compounds such as biochar, for the removal of OC compounds are analyzed and compared with the use of synthetic supports. A qualitative and quantitative comparison of the reported results was made. In this context, the use of peanut shells is highlighted in view of the increasing peanut production worldwide. The linkage of methods with circular economy approaches that can be applied in practice is discussed. [ABSTRACT FROM AUTHOR]

It is possible to remove volatile organic compounds containing chlorine (CVOCs, such as chlorobenzene) in a single device designed for selective catalytic reduction of NOX with NH3 for the industries containing CVOCs and NOX. Breaking the efficiency-selectivity trade-off in chlorobenzene oxidation remains a major challenge due to the conjugation of halogen atoms with the benzene ring and the reducing nature of NH3. A stepwise synthesis strategy is demontrated to disperse dual Ru/Cu Lewis acid sites outside and inside the zeolite channel. Under the confinement of zeolite, the Ru4+ Lewis acid site on the external surface of the zeolite promotes chlorobenzene oxidation by weakening the p-n conjugate structure of Cl and benzene ring, while the Cu2+ Lewis acid site within the internal channel converts NOX and NH3 to N2. The mutual interference between catalytic oxidation and reduction is successfully avoided. Therefore, the low toxic CO2 and HCl selectivity experience a considerable increase from 21% to 86%, and from 51% to 94% with 91% conversion of chlorobenzene, while maintaining excellent elimination performance for NO (with N2 selectivity exceeding 90%). The incorporation of separated active sites and reaction spaces into the design may offer potentials for other energy and environmental applications. [ABSTRACT FROM AUTHOR]

An integrated process of phase transfer nucleophilic substitution and coalescence is proposed to upgrade coal tar by simultaneously removing organochlorine compounds (OOCs) and water. For the phase transfer catalysts (PTCs) and nucleophiles, polyethylene glycol 400 (PEG‐400) and triethanolamine (TEOA) were the most effective to remove OOCs from coal tar. The optimal parameters of the dichlorination process in terms of molar ratio of PEG‐400 and TEOA to OOCs, reaction temperature, reaction time, and stirring speed were determined. The chloride removal efficiency reached 80.66 % when glass fiber was used for oil‐water coalescence separation. A promising method for simulllltaneously removing chloride and water from coal tar is provided. [ABSTRACT FROM AUTHOR]

This study investigates selected secondary atmospheric responses to the widely reported emission change attributed to COVID‐19 lockdowns in the highly polluted Indo‐Gangetic Plain (IGP) using ground‐based measurements of trace gases and particulate matter. We used a chemical box‐model to show that production of nighttime oxidant, NO3, was affected mainly by emission decrease (average nighttime production rates 1.2, 0.8 and 1.5 ppbv hr−1 before, during and relaxation of lockdown restrictions, respectively), while NO3 sinks were sensitive to both emission reduction and seasonal variations. We have also shown that the maximum potential mixing ratio of nitryl chloride, a photolytic chlorine radical source which has not been previously considered in the IGP, is as high as 5.5 ppbv at this inland site, resulting from strong nitrate radical production and a potentially large particulate chloride mass. This analysis suggests that air quality measurement campaigns and modeling explicitly consider heterogeneous nitrogen oxide and halogen chemistry. Plain Language Summary: The Indo‐Gangetic Plain (IGP) is one of the most polluted regions on earth, with poor air quality affecting the majority of the Indian population. The atmospheric chemistry that transforms major regional emissions into harmful secondary pollutants is complex. Here, we quantify, for the first time, several important oxidative processes and show the potential for substantial oxidation of biogenic volatile organic compounds and the production of chlorine through unconventional chemistry in the IGP. We further show how these chemical cycles varied due to the emission reductions as a result of COVID‐19 lockdown, findings that will serve to define their sensitivity to future emission changes in the region. Key Points: Atmospheric response in the Indo‐Gangetic Plain varied according to seasonal changes and emissions reductions due to COVID‐19 lockdownNO3 production was mainly affected by emission changes, while NO3 sinks were sensitive to both emissions and seasonal changesNitryl chloride, a photolytic chlorine radical source not previously considered in the inland Indo‐Gangetic Plain, may be up to 5.5 ppbv [ABSTRACT FROM AUTHOR]

Organic compounds featuring a chlorine substituted stereocenter are frequently found in nature and are interesting for pharmaceutical applications and as synthetic building blocks. Catalytic methods to generate such stereocenters by C,H bond functionalization are still relatively rare. Here we report the first catalytic asymmetric chlorination of isoxazolinones, a synthetically and biologically interesting class of heterocycles, which can be considered as precursors for β‐aminoacids. The title reaction was catalyzed with high enantioselectivity by a planar chiral ferrocene based palladacycle in high to excellent yields. It is showcased that the products are valuable for post‐synthetic transformations. An SN2 reaction proceeded with smooth inversion of the absolute configuration. The substitution product could then be transformed into an α‐azido β‐aminoacid derivative via a reductive, diastereoselective ring opening. [ABSTRACT FROM AUTHOR]

Most of the organics detected on Mars so far are aliphatic and aromatic organo‐chlorine compounds. The smallest were first identified by the thermal treatment of the solid samples by Viking in 1976; although at the time, they were attributed to contamination. Since 2012, a larger variety of structures have been identified by the Sample Analysis at Mars experiment aboard the Curiosity rover. Evidence suggests that the chlorohydrocarbons formed during pyrolysis of sedimentary materials. Laboratory experiments show that heating of samples containing oxychlorines, such as chlorates (ClO3−) and perchlorates (ClO4−), along with organic matter present at Mars' surface is the logical source of these compounds. Nevertheless, this discovery of indigenous organic matter in the Mars regolith raises important questions: How do the oxychlorines influence the pyrolysis of organics? What are the organics precursors of the organo‐chlorinated molecules detected on Mars? Is there a way to identify the parent molecules in a sample after pyrolysis? This paper presents the results of systematic laboratory experiments of the products formed during the pyrolysis of organic compounds from three chemical families—polycyclic aromatic hydrocarbons, amino acids, and carboxylic acids—in presence of calcium perchlorates. Results show that the polycyclic aromatic hydrocarbon parent molecules and most of the carboxylic acids are still detectable after pyrolysis in presence of calcium perchlorate and that the degradation and/or evolution of all parent molecules mostly depends on their chemical nature. In addition, we demonstrate that the chlorohydrocarbons detected on Mars by the Sample Analysis at Mars instrument could come from the three chemical families studied. Plain Language Summary: Organic molecules are the building blocks of life as we know it, and detecting them on the surface of Mars has been one of the major goals of Mars exploration. Viking landers in 1976, followed by the Curiosity rover in 2012, discovered simple chlorine‐bearing organics on Mars. These chlorohydrocarbons are known to be mainly produced by the instrument itself, through chemical reactions at high temperatures between other organic molecules thermally extracted from solid rock and soil samples that react with the oxidizing minerals present on Mars (e.g., perchlorates). Studying the influence of the minerals like perchlorates on the thermal extraction of different parent molecules requires thorough experimental studies like this one. Our work constrains the potential parent molecules of the chlorohydrocarbons detected on Mars in the presence of calcium perchlorate, thereby shedding light on the past and present habitability of Mars. Key Points: A systematic study reveals the influence of calcium perchlorate during the pyrolysis of organic compounds from various chemical familiesSome parent organics can be identified after thermal extraction as well as through the production of characteristic pyrolysis product(s)The precursors of the chlorohydrocarbons detected on Mars with the SAM instrument could originate from the three chemical families studied [ABSTRACT FROM AUTHOR]

Dichloromethane (CH2Cl2) and perchloroethylene (C2Cl4) are chlorinated very short lived substances (Cl‐VSLS) with anthropogenic sources. Recent studies highlight the increasing influence of such compounds, particularly CH2Cl2, on the stratospheric chlorine budget and therefore on ozone depletion. Here, a multiyear global‐scale synthesis inversion was performed to optimize CH2Cl2 (2006–2017) and C2Cl4 (2007–2017) emissions. The approach combines long‐term surface observations from global monitoring networks, output from a three‐dimensional chemical transport model (TOMCAT), and novel bottom‐up information on prior industry emissions. Our posterior results show an increase in global CH2Cl2 emissions from 637 ± 36 Gg yr−1 in 2006 to 1,171 ± 45 Gg yr−1 in 2017, with Asian emissions accounting for 68% and 89% of these totals, respectively. In absolute terms, Asian CH2Cl2 emissions increased annually by 51 Gg yr−1 over the study period, while European and North American emissions declined, indicating a continental‐scale shift in emission distribution since the mid‐2000s. For C2Cl4, we estimate a decrease in global emissions from 141 ± 14 Gg yr−1 in 2007 to 106 ± 12 Gg yr−1 in 2017. The time‐varying posterior emissions offer significant improvements over the prior. Utilizing the posterior emissions leads to modeled tropospheric CH2Cl2 and C2Cl4 abundances and trends in good agreement to those observed (including independent observations to the inversion). A shorter C2Cl4 lifetime, from including an uncertain Cl sink, leads to larger global C2Cl4 emissions by a factor of ~1.5, which in some places improves model‐measurement agreement. The sensitivity of our findings to assumptions in the inversion procedure, including CH2Cl2 oceanic emissions, is discussed. Plain Language Summary: The 1987 Montreal Protocol banned production for dispersive uses of major ozone‐depleting gases, such as chlorofluorocarbons, due to their role in depletion of the stratospheric ozone layer. In consequence, the ozone layer is expected to recover in coming decades, as stratospheric chlorine from banned substances slowly declines. However, chlorinated very short lived substances (Cl‐VSLS), not controlled by the Montreal Protocol, represent a small, but growing, source of atmospheric chlorine that could potentially slow ozone recovery. It is thus important that the magnitude of emissions of these compounds, their spatial distribution, and changes with time are quantified. Here, we combined observations of Cl‐VSLS, prior estimates of their emissions, and a chemical transport model to produce an optimized set of emission estimates on a region‐by‐region basis between 2006 and 2017. We show that industrial emissions of dichloromethane, the most abundant Cl‐VSLS, increased by ~84% within this period, predominately due to an increase in Asian emissions, while European and North American emissions decreased. Over 2007–2017, emissions of perchloroethylene, a less abundant Cl‐VSLS, decreased, particularly in Europe and North America. We show that our new emission estimates lead to better agreement with observational data compared to previous estimates. Key Points: Global CH2Cl2 emissions increased by ~85% between 2006 and 2017, mostly due to increasing emissions from AsiaGlobal C2Cl4 emissions decreased in the same period by ~25%, mainly due to reduced emissions from Europe and North AmericaPosterior CH2Cl2 and C2Cl4 emissions provide good agreement with surface and aircraft observational data [ABSTRACT FROM AUTHOR]

High levels of organochlorine contaminants (OCs) have been found in arctic char (Salvelinus alpinus) from Lake Ellasjøen, Bjørnøya (Norwegian Arctic). The aim of the present study was to investigate the potential genotoxic effect of environmental organochlorine contaminant exposure in arctic char from Ellasjøen compared with arctic char from the low‐contaminated Lake Laksvatn nearby. Blood was analyzed using agarose gel electrophoresis and image data analysis to quantify the fraction of total DNA that migrated into the gel (DNA‐FTM) as a relative measure of DNA double‐strand breaks (DSBs). Analysis by GC‐MS of muscle samples showed an average 43 times higher concentration of ΣOCs in arctic char from Ellasjøen (n = 18) compared with Laksvatn char (n = 21). Char from Lake Ellasjøen had a much higher frequency of DSBs, as measured by DNA‐FTM, than char from Lake Laksvatn. Principal component analysis and multiple linear regressions show that there was a significant positive relationship between DSBs and levels of organochlorine contaminants in the char. In addition, DSBs were less frequent in reproductively mature char than in immature char. The results suggest that organochlorine contaminants are genotoxic to arctic char. Environ Toxicol Chem 2019;38:2405–2413. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC [ABSTRACT FROM AUTHOR]

Background: The insecticide exposure has been linked to Parkinson's disease (PD). In the present study, we used a most widely used cell line in study of PD, the SH‐SY5Y cells, to investigate mechanisms of chlorpyrifos (CPF) induced cell toxicity and the possible roles of cell pyroptosis and oxidative stress in SH‐SY5Y cells, as well as role of miR‐181/SIRT1/PGC‐1α/Nrf2 signaling pathway in this process. Methods: SH‐SY5Y cells were treated with different concentrations of CPF. Cell viability was measured using CCK‐8 assay. Cell pyroptosis was determined by immunofluorescence of caspase‐1 and TUNEL assay. The miR‐181 (has‐miR‐181‐5p) level was determined by qRT‐PCR. Expression of SIRT1, PGC‐1α, Nrf2, and pyroptosis related proteins NLRP3, caspase‐1, IL‐1β, and IL‐18 was determined by both qRT‐PCR and Western blotting. Results: Cell viability was found to be decreased with the increased CPF concentrations. The pyroptosis related proteins, ROS levels, as well as level of caspase‐1 and the TUNEL positive cells were all significantly up‐regulated by CPF. Meanwhile, expression of miR‐181 and pyroptosis proteins was also enhanced, while the SIRT1/PGC‐1α/Nrf2 signaling was inhibited by CPF. Knockdown of Nrf2 significantly up‐regulated the expression of pyroptosis related proteins, ROS level, caspase‐1, and the TUNEL positive cells, while over‐expression of Nrf2 resulted in opposite results. The expression of PGC‐1α and Nrf2 was significantly down‐regulated when SIRT1 was inhibited, while over‐expressed SIRT1 led to increased PGC‐1α and Nrf2 levels. Besides, miR‐181 promoted the CPF induced activation of pyroptosis and oxidative stress, as well as down‐regulated SIRT1/PGC‐1α/Nrf2 signaling, while inhibition of miR‐181 led to opposite results. Conclusions: Chlorpyrifos could inhibit cell proliferation, activate cell pyroptosis and increase susceptibility on oxidative stress‐induced toxicity by elevating miR‐181 through down‐regulation of the SIRT1/PGC‐1α/Nrf2 pathway in human neuroblastoma SH‐SY5Y cells. This study might give deeper insights for mechanisms of CPF induced toxicity and might give some novel research targets for PD treatment. [ABSTRACT FROM AUTHOR]

The article discusses new processes and tools for assessing reactive mineral-mediated abiotic contaminant transformation. It discusses iron-mediated chlorinated volatile organic compounds (CVOC) transformation processes, and offers suggestions with regard to abiotic processes in remedy design and natural attentuation evaluations. It discusses tools such as Min-Traps or Mineral Traps which are specialized sampling devices.

Background: Workers raised concerns over suspected excesses of mortality at automotive electronics manufacturing facilities in Huntsville, Alabama. Methods: A study of 4396 UAW members ever‐employed at Huntsville facilities between 1972 and 1993 was conducted with mortality follow‐up through 2016. Standardized Mortality Ratios (SMRs) were estimated using U.S. and Alabama reference rates. Results: Relative to U.S. rates, there was a modest excess of all‐cause mortality among White female workers (SMR 1.08, 95%CI: 0.99‐1.18) and among all workers hired <1977 at the original plant building (SMR 1.10, 95%CI: 0.99‐1.22). There was excess nervous system disorder (SMR 1.24, 95%CI: 0.91‐1.65) and brain and nervous system cancer (SMR 1.31, 95%CI: 0.67‐2.28) mortality. Estimates for several causes of interest were imprecise. Conclusions: All‐cause mortality estimates were greater than anticipated based on results from other UAW cohorts. The excess of nervous system disease mortality is consistent with other studies of electronics workers exposed to lead‐solder and chlorinated solvents. [ABSTRACT FROM AUTHOR]

Background: This study was carried out in response to worker concerns over their exposure to lead solder and chlorinated solvents at automotive electronics manufacturing plants in Huntsville, Alabama. Methods: A study of 4396 United Autoworkers members ever‐employed at the plants between 1972 and 1993 was conducted with mortality follow‐up through 2016. Poisson regression was used to estimate mortality rate ratios (RR) according to employment characteristics, including calendar period of employment. Results: Pre‐1977 hires exhibited elevated adjusted rates of all‐cause (RR, 1.29; 95% confidence interval [CI], 1.09‐1.52), cardiovascular (RR, 1.38; 95% CI, 1.03‐1.86), and digestive system (RR, 2.31; 95% CI, 1.04‐5.10) disease mortality relative to the most recent hire group (1984‐1993). Never‐ versus ever‐employment in a skilled trade job was associated with elevated adjusted rates of all‐cause, all‐cancer, and cardiovascular disease mortality. Nervous system disorder mortality was greatest among 1977‐1983 hires. Conclusions: Elevated mortality among pre‐1977 hires is consistent with worker concerns over greater exposure to hazards at the original plant building. [ABSTRACT FROM AUTHOR]

In birds, incubation‐related behaviors and brood patch formation are influenced by hormonal regulation such as prolactin secretion. Brood patch provides efficient heat transfer between the incubating parent and the developing embryo in the egg. Importantly, several environmental contaminants are already known to have adverse effects on avian reproduction. However, relatively little is known about the effect of contaminants on incubation temperature (Tinc) in wild birds. By using temperature thermistors placed into artificial eggs, we investigated whether the most contaminated parent birds are less able to provide appropriate egg warming and thus less committed to incubating their clutch. Specifically, we investigated the relationships among 3 groups of contaminants (organochlorines, perfluoroalkyl substances [PFASs], and mercury [Hg]) with Tinc and also with prolactin concentrations and brood patch size in incubating Arctic black‐legged kittiwakes (Rissa tridactyla). Our results reveal that among the organochlorines considered, only blood levels of oxychlordane, the main metabolite of chlordane, a banned pesticide, were negatively related to the minimum incubation temperature in male kittiwakes. Levels of PFASs and Hg were unrelated to Tinc in kittiwakes. Moreover, our study suggests a possible underlying mechanism: since we reported a significant and negative association between blood oxychlordane concentrations and the size of the brood patch in males. Finally, this reduced Tinc in the most oxychlordane‐contaminated kittiwakes was associated with a lower egg hatching probability. Environ Toxicol Chem 2018;37:2881–2894. © 2018 SETAC [ABSTRACT FROM AUTHOR]

Abstract: Studies were conducted to develop methods to assess the effects of a complex mixture of polychlorinated biphenyls (PCBs) in the domestic chicken (Gallus domesticus). Treatments were administered by egg injection to compare embryonic effects of an environmentally relevant PCB congener mixture in the domestic chicken over a range of doses. Chicken eggs were injected with the PCB mixture with a profile similar to that found in avian eggs collected on the upper Hudson River, New York, USA, at doses that spanned 0 to 98 μg/g egg. Eggs were hatched in the laboratory to ascertain hatching success. In the domestic chicken, the median lethal dose was 0.3 μg/g. These data demonstrate adverse effects of an environmentally relevant PCB mixture and provide the basis for further work using in vitro and other models to characterize the potential risk to avian populations. Environ Toxicol Chem 2018;37:2513–2522. © 2018 SETAC [ABSTRACT FROM AUTHOR]

A series of fused 4,5‐borazaropyrrolo[1,2‐a]quinolines have been prepared from potassium organotrifluoroborates and substituted 1‐(2‐aminophenyl)pyrroles via direct formation of C–B and N–B bonds. The target products were obtained in moderate to high yields under mild conditions. The optical properties of some products were investigated by UV/Vis spectroscopy and spectrofluorometry. Moreover, the influence of structural modification on the spectroscopic and electronic properties was studied by DFT calculations. [ABSTRACT FROM AUTHOR]

Abstract: Recent epidemiological studies have revealed significant positive associations between exposure to organochlorine (OC) pesticides and occurrence of the metabolic syndrome and there are a growing number of animal‐based studies to support causality. However, the cellular mechanisms linking OC compound exposure and metabolic dysfunction remain elusive. Therefore, the present study was designed to determine if direct exposure to three highly implicated OC compounds promoted hepatic steatosis, the hepatic ramification of the metabolic syndrome. First, the steatotic effect of p,p′‐dichlorodiphenyldichloroethylene (DDE), oxychlordane, and trans‐nonachlor was determined in freshly isolated rat primary hepatocytes. Exposure to trans‐nonachlor significantly increased neutral lipid accumulation as opposed to DDE and oxychlordane. To determine possible mechanisms governing increased fatty acid availability, the effects of trans‐nonachlor exposure on fatty acid uptake, de novo lipogenesis, triglyceride secretion, and fatty acid oxidation were explored. Trans‐nonachlor did not significantly alter fatty acid uptake. However, insulin‐stimulated de novo lipogenesis as well as basal expression of fatty acid synthase, a major regulator of lipogenesis were significantly increased following trans‐nonachlor exposure. Interestingly, there was a significant decrease in fatty acid oxidation following trans‐nonachlor exposure. This decrease in fatty acid oxidation was accompanied by a slight, but significant increase in oleic acid‐induced cellular triglyceride secretion. Therefore, taken together, the present data indicate direct exposure to trans‐nonachlor has a more potent pro‐steatotic effect than exposure to DDE or oxychlordane. This pro‐steatotic effect of trans‐nonachlor appears to be predominately mediated via increased de novo lipogenesis and decreased fatty acid oxidation. [ABSTRACT FROM AUTHOR]

Polychlorinated terphenyls (PCT), a group of persistent, low‐volatile environmental pollutants are rarely investigated because of their high number of congeners and missing practicable analytical methods. Therefore, the proven strategy is pursued to define a set of reference substances that is analyzed representatively of all PCT. For this purpose, 29 tetra‐ to hepta‐chlorinated terphenyls are chosen, easily reaching a coplanar conformation because of lacking ortho‐substitutions. Now, the synthesis work has been finished by producing the so‐far‐missing 17 single coplanar PCT. Spectroscopic data of these compounds, generated by nuclear magnetic resonance, Fourier transform infrared spectroscopy, and mass spectrometry, as well as short notes on the synthesis procedures, are provided herein. [ABSTRACT FROM AUTHOR]

A crude oil from Shengli oilfield of China was extracted with N,N‐dimethylformamide (DMF) for separation and enrichment of organic chlorides. The resulting extract with relatively higher chlorine concentration was analyzed with gas chromatography–mass spectrometry (GC/MS). Among the identified heteroatom compounds in the extract sample, nitrogen‐containing compounds were most abundant in the extract sample, followed by chlorine‐, sulfur‐, and oxygen‐containing compounds, respectively. Four organochlorines with an aromatic core structure, i.e., 5‐chloro‐2‐methylaniline, 2‐chloro‐6‐methylaniline, 4‐chloro‐2‐nitrotoluene, and 1‐(5‐chloro‐2‐hydroxyphenyl)ethanone, were identified from crude oil extract. The dominant abundant organic chloride is 5‐chloro‐2‐methylaniline with relative content of 65.1% in the total of identified organic chlorides, followed by 1‐(5‐chloro‐2‐hydroxyphenyl)ethanone of 16.3%, 2‐chloro‐6‐methylaniline of 14.5%, and 4‐chloro‐2‐nitrotoluene of 4.1%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Chemical use in society is growing rapidly and is one of the five major pressures on biodiversity worldwide. Since empirical toxicity studies of pollutants generally focus on a handful of model organisms, reliable approaches are needed to assess sensitivity to chemicals across the wide variety of species in the environment. Phylogenetic comparative methods (PCM) offer a promising approach for toxicity extrapolation incorporating known evolutionary relationships among species. If phylogenetic signal in toxicity data is high, i.e., closely related species are more similarly sensitive as compared to distantly related species, PCM could ultimately help predict species sensitivity when toxicity data are lacking. Here, we present the largest ever test of phylogenetic signal in toxicity data by combining phylogenetic data from fish with acute mortality data for 42 chemicals spanning 10 different chemical classes. Phylogenetic signal is high for some chemicals, particularly organophosphate pesticides, but not necessarily for many chemicals in other classes (e.g., metals, organochlorines). These results demonstrate that PCM may be useful for toxicity extrapolation in untested species for those chemicals with clear phylogenetic signal. This study provides a framework for using PCM to understand the patterns and causes of variation in species sensitivity to pollutants. [ABSTRACT FROM AUTHOR]

West Nile virus (WNV) is maintained cryptically primarily in avian (passerine) populations, where it is transmitted by Culex spp. mosquitoes. Mosquito-control measures currently include physical activities to reduce mosquito-breeding sites and the application of mosquito larvicides or aerosolized insecticides to kill adults (adulticides) when arboviral diseases such as WNV or Zika virus are detected in mosquito populations. Organochlorine, organophosphorus, carbamate, and pyrethroid insecticides are often used. Previous work suggests an effect of pyrethroids on the immune system in a variety of vertebrates. We examined the effects of exposure to aerosolized Permanone® 30:30 insecticide (permethrin and piperonyl butoxide in soy oil vehicle) at approximately 103 to 106 times potential environmental concentrations on the response of captive zebra finches ( Taeniopygia guttata) to experimental challenge with WNV. Compared to vehicle control birds, WNV outcome was unchanged (65% of birds produced a viremia) in the 'low' exposure (9.52 ± 3.13 mg/m3 standard deviation [SD] permethrin) group but reduced in the 'high' exposure (mean 376.5 ± 27.9 mg/m3 SD permethrin) group (30% were viremic; p < 0.05). After clearing WNV infection, birds treated with Permanone regained less body mass than vehicle-treated birds ( p < 0.001). The present study suggests that exposure to aerosolized Permanone insecticide at levels exceeding typical application rates has the potential to not change or to mildly enhance a bird's resistance to WNV. Environ Toxicol Chem 2017;36:3376-3386. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. [ABSTRACT FROM AUTHOR]

Environmental pollutants may act as endocrine disruptors in animals. Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) enter the food chain and may accumulate in the fatty animal tissues, including adrenals. To our knowledge, no previous study has investigated their presence in the human normal adrenal (NA) cortex and aldosterone-producing adenomas (APA). Surgical fragments of APA from 11 patients and NA from 8 kidney donors were analyzed for 16 PCBs congeners and 10 OCPs. A Matrix Solid-Phase Dispersion (MSPD) method for simultaneous determination of the target compounds in cortex homogenates was developed. A gas-chromatography triple quadrupole mass spectrometry (Triple Quad GC-MS) system was used for the analysis. Data were analyzed using Random Forest and Wilcoxon's rank-sum test. OCPs and PCBs were found in specimens from both types. A subset of pollutants characterized APA more than NA. Higher concentrations (μg g−1) in APA were observed for α-, β-, and γ- Hexachlorocyclohexane (HCH) (1.48 ± 3.32 vs. 0.17 ± 0.19, P = 0.028; 2.81 ± 2.10 vs. 0.96 ± 0.98, P = 0.011; 2.16 ± 4.85 vs. 0.17 ± 0.26, P = 0.004, respectively), as well as for Hexachlorobenzene (HCB) and for PCBs 28, 52 and 101 (3.41 ± 3.11 vs. 0.97 ± 1.06, P = 0.021; 2.34 ± 4.68 vs. 0.25 ± 0.22, P = 0.039; 0.58 ± 1.19 vs. 0.06 ± 0.02, P = 0.002; 0.26 ± 0.43 vs. 0.05 ± 0.00, P = 0.001, respectively). Environmental organochlorine pollutants were shown to be present in the human normal and abnormal adrenal cortex, deserving future investigation on their possible role as adrenal endocrine disruptors in human disease. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

1,2-Dichloropropane (1,2-DCP) and dichloromethane (DCM) are possible causative agents associated with the development of cholangiocarcinoma in employees working in printing plant in Osaka, Japan. However, few reports have demonstrated an association between these agents and cholangiocarcinoma in rodent carcinogenicity studies. Moreover, the combined effects of these compounds have not been fully elucidated. In the present study, we evaluated the in vivo mutagenicity of 1,2-DCP and DCM, alone or combined, in the livers of gpt delta rats. Six-week-old male F344 gpt delta rats were treated with 1,2-DCP, DCM or 1,2-DCP + DCM by oral administration for 4 weeks at the dose (200 mg kg−1 body weight 1,2-DCP and 500 mg kg−1 body weight DCM) used in the carcinogenesis study performed by the National Toxicology Program. In vivo mutagenicity was analyzed by gpt mutation/Spi− assays in the livers of rats. In addition, gene and protein expression of CYP2E1 and GSTT1, the major enzymes responsible for the genotoxic effects of 1,2-DCP and DCM, were analyzed by quantitative polymerase chain reaction and western blotting. Gpt and Spi− mutation frequencies were not increased by 1,2-DCP and/or DCM in any group. Additionally, there were no significant changes in the gene and protein expression of CYP2E1 and GSTT1 in any group. These results indicated that 1,2-DCP, DCM and 1,2-DCP + DCM had no significant impact on mutagenicity in the livers of gpt delta rats under our experimental conditions. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Hepatic steatosis is recognized as an independent risk factor for the development of cardiovascular disease. While obesity and type 2 diabetes are well-established risk factors in the development of hepatic steatosis, recent studies have revealed exposure to mixtures of persistent organic pollutants (POPs), which are environmental contaminants in various fatty foods, can promote steatosis. Thus, the present study was designed to determine if exposure to a defined mixture of prevalent polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides or their metabolites promote hepatic steatosis in a genetically induced model of type 2 diabetes, the leptin-deficient ob/ob mouse. Male C57BL/6J wild type (WT) or ob/ob mice were administered an environmentally relevant mixture of PCBs and OCs for 7 weeks via oral gavage. Exposure to POPs did not significantly alter fasting serum glucose or insulin levels. However, POPs exposure significantly increased hepatic triglyceride content in ob/ob animals, while decreasing serum triglyceride levels. This POPs-mediated increase in hepatic triglyceride content did not appear to be associated with significantly increased inflammation in either the liver or adipose. Exposure to POPs significantly induced the expression of cytochrome P450 3a11 in WT animals, yet the expression of this cytochrome was significantly downregulated in ob/ob animals regardless of POPs exposure. Taken together, the present data indicate exposure to an environmentally relevant mixture of both PCBs and OC pesticides in ob/ob mice promotes hepatic steatosis while decreasing hypertriglyceridemia, which demonstrates exposure to a defined mixture of POPs alters systemic lipid metabolism in a genetically induced model of obesity and type 2 diabetes. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1399-1411, 2017. [ABSTRACT FROM AUTHOR]

The present study explored short-term temporal variations in circulating concentrations of 3 legacy organochlorines with different physicochemical properties (polychlorinated biphenyl 153 [PCB-153], p,p′-dichlorodiphenyldichloroethylene [DDE], and hexachlorobenzene [HCB]) in breeding kittiwakes ( Rissa tridactyla) in a colony in Svalbard (78°N), Norwegian Arctic. Concentrations were measured in blood of a large number ( n = 412-521 blood samples, depending on the data analyses) of prebreeding, incubating, and chick-rearing birds over a period of 5 yr (2007-2011). The PCB-153 concentrations were equal in male and female blood in the prebreeding period, whereas females had significantly lower concentrations during incubation and chick rearing, probably because of their ability to eliminate organochlorines through egg laying. A similar temporal pattern was observed with DDE, although the lower concentrations in incubating females were not significant. Males and females had similar concentrations of HCB over all reproductive stages. The concentrations of all 3 compounds varied greatly between years. The concentrations of PCB-153 tended to decline over the study period, whereas concentrations of HCB showed an increasing trend, especially among chick-rearing males late in the season. Concentrations of PCB-153 increased approximately 2.5 times from the prebreeding to the chick-rearing period, concurrent with mobilization of body lipids (reduced body mass). A similar, but less pronounced trend was found for HCB. For DDE, however, kittiwakes had the highest concentrations in the prebreeding period, suggesting relatively high exposure in their winter areas. The present study documented large variations in circulating concentrations of legacy organochlorines among and within breeding seasons in kittiwakes, but the alterations within seasons were relatively consistent from year to year. Environ Toxicol Chem 2017;36:442-448. © 2016 SETAC [ABSTRACT FROM AUTHOR]

Exposure to pesticides may increase the generation of reactive oxygen species ( ROS), leading to oxidation of cell membrane lipids and proteins. Although fruit bats are potentially exposed to pesticides during their entire lifespan, the impacts of this exposure are still poorly investigated. We examined the effects of low, commercially recommended concentrations (0, 1.05 and 2.1 g/l) of an organochlorine insecticide endosulfan ( EDS) formulation on oxidative responses in the liver and kidneys of Neotropical fruit bats ( Artibeus lituratus), as well as possible liver morphological alterations following a 35-day oral exposure. Superoxide dismutase activity was significantly decreased upon exposure to 1.05 g/l of EDS in the liver and kidneys, catalase was decreased in the liver of 2.1 g/l EDS-exposed bats, while glutathione S-transferase was increased in the liver of 2.1 g/l EDS-exposed bats. Protein carbonyls increased following the exposure to the highest EDS dose tested. Endosulfan-induced morphological alterations in the liver included cell degeneration and cell death, with apparent cytoplasm lipid accumulation (steatosis) and pyknotic nuclei, karyolysis and deposit of collagen fibres. Our findings suggest that exposure to low concentrations of EDS induced a certain extent of oxidative damage in fruit bats, which may have led to liver morphological alterations. [ABSTRACT FROM AUTHOR]

Sample preparation is often the main bottleneck in analyzing biological samples. Particularly, effective evaluation of sample preparation conditions usually involves multiple factors and tedious and time-consuming experiments. In this study, fractional factorial design, specifically orthogonal array testing, was employed to screen and optimize multiple extraction parameters in concise but representative experiments. An efficient and sensitive method was developed to determine organophosphorus and organochlorine pesticide residues in tobacco, via microwave-assisted extraction and gas chromatography coupled with mass spectrometry detection. With orthogonal array design, screening, and optimization tests were subsequently conducted to determine the range, impact rank, and possible interactions of extraction temperature, time, microwave power, additive salt, and additive water. Orthogonal array testing selectively reduces the size and cost of experiments and meanwhile provides more information compared to the traditional experimental design that optimizes one factor at a time. A good linear range (0.02-2.00 μg/mL), limits of detection (0.001-0.098 μg/mL), and recovery rates (70.4-107.1%) were demonstrated by spiking known concentrations of multiple pesticide standards in tobacco samples. The established method was then successfully applied to the determination of multipesticide residues in raw tobacco leaves and commercial cigarettes. [ABSTRACT FROM AUTHOR]

Triclocarban (TCC) is an antimicrobial agent routinely detected in surface waters that has been hypothesized to interact with the vertebrate endocrine system. The present study examined the effects of TCC alone and in combination with the model endocrine disruptor 17β-trenbolone (TRB) on fish reproductive function. Adult Pimephales promelas were continuously exposed to either 1µg TCC/L or 5µg TCC/L, to 0.5µg TRB/L, or to a mixture (MIX) of 5µg TCC/L and 0.5µg TRB/L for 22 d, and a variety of reproductive and endocrine-related endpoints were examined. Cumulative fecundity was significantly reduced in fathead minnows exposed to TRB, MIX, or 5µg TCC/L. Exposure to 1µg TCC/L had no effect on reproduction. In general, both TRB and MIX treatments caused similar physiological effects, evoking significant reductions in female plasma vitellogenin, estradiol, and testosterone, and significant increases in male plasma estradiol. Based on analysis of the ovarian transcriptome, there were potential pathway impacts that were common to both TRB- and TCC-containing treatment groups. In most cases, however, those pathways were more plausibly linked to differences in reproductive status than to androgen-specific functions. Overall, TCC was reproductively toxic to fish at concentrations at or near those that have been measured in surface water. There was little evidence that TCC elicits reproductive toxicity through a specific mode of endocrine or reproductive action, nor that it could augment the androgenic effects of TRB. Nonetheless, the relatively small margin of safety between some measured environmental concentrations and effect concentrations suggests that concern is warranted. [ABSTRACT FROM AUTHOR]

Background Majantol® [2,2-dimethyl-3-(3-methylphenyl)propan-1-ol; CAS no. 103694-68-4] has been identified as a contact allergen in humans, despite negative animal tests. Hence impurities, specifically organochlorines, in Majantol® might have been the reason for positive patch test reactions in the past. Objectives To assess elicitation via patch testing with a standard market-quality version of Majantol® ('normal') with a normal content of organochlorine impurities, as compared with an ultra-purified version of Majantol® ('pure'), without detectable organochlorine impurities. Methods Between 1 October 2013 and 31 December 2014, two different Majantol® patch test preparations of the above-mentioned quality were tested 5% pet. in parallel in the 'monitor series', that is, together with the baseline series, in 8005 consecutive patients from 33 departments of dermatology of the Information Network of Departments of Dermatology ( IVDK). Results Fifty-three of 7740 [0.69% (95% CI: 0.51-0.87)] patch tested patients reacted to at least one Majantol® preparation. The majority (n = 32) (60.4%) reacted to both preparations, 13 (24.5%) reacted to the 'normal' version only, and 8 (15.1%) reacted to the 'pure' version only. There was good concordance between results [ Cohen's kappa 0.75 (95% CI: 0.65-0.85)], and there was no significant difference in frequency or intensity between the two preparations. More doubtful or irritant reactions than positive reactions were observed, and> 80% of all positive reactions were weak positive. Conclusion Organochlorine impurities are very probably not the cause of allergic reactions to Majantol®. [ABSTRACT FROM AUTHOR]

A fast, sensitive, and convenient technique consisting of a miniaturized solid-phase extraction method named microextraction in packed syringe coupled with gas chromatography and mass spectrometry was developed for the preconcentration and determination of some pesticides, including hexachlorobenzene, heptachlor, alachlor, aldrine, and metolachlore, in natural water samples. Carboxyl-purified multiwalled carbon nanotubes were used as a sorbent in microextraction in packed syringe. Based on this technique, 6.0 mg of multiwalled carbon nanotubes was inserted in the syringe between two polypropylene frits. The analytes would be adsorbed on the solid phase, and would subsequently be eluted using organic solvents. The influence of some important parameters involved including the solution pH, type, and volume of the organic desorption solvent, and amount of the multiwalled carbon nanotubes sorbent on the extraction efficiency of the selected pesticides were investigated. The proposed method showed a good linearity in the range of 0.1-25.0 ng/mL and low limits of detection in the range of 0.02-0.19 ng/mL using the selected ion-monitoring mode. Reproducibility of the method was in the range of 3.3-8.5% for the studied pesticides. Also to evaluate the matrix effect, the developed method was applied to the preconcentration and determination of the selected pesticides in different water samples. [ABSTRACT FROM AUTHOR]

Antimicrobial novel substituted maleimido aromatic hydrazides were synthesized from N-[4-(chlorocarbonyl) phenyl] maleimide with salicylhydrazide, p-aminobenzohydrazide, or p-aminosalicylhydrazide. They were characterized by Fourier transform infrared (FTIR), hydrogen-1 nuclear magnetic resonance (1H-NMR), mass spectra, elemental analyses, and antimicrobial activities. These derivatives were investigated as thermal stabilizers for rigid poly(vinyl chloride) (PVC) at 180°C in air by measuring the rate of dehydrochlorination, the extent of discoloration, and the changes that occurred in the molecular masses of the degraded PVC samples. The previously reported stabilizing efficiency data of a nonsubstituted derivative, which was synthesized from N-[4-(chlorocarbonyl) phenyl] maleimide with benzohydrazide, is also given for comparison. The results reveal the greater stabilizing efficiency of the investigated derivatives as shown by their longer thermal stability (Ts) periods and lower dehydrochlorination rates in relation to dibasic lead carbonate, cadmium-barium-zinc stearate, and n-octyltin mercaptide industrial stabilizers. The stabilizing efficiency increases with the introduction of electron donating substituent groups in the aromatic ring of the stabilizer molecules. Moreover, the investigated stabilizers impart better color stability for the degraded samples as compared with the reference stabilizers. A synergistic effect is achieved when the materials under investigation were mixed in various weight ratios with any of the reference stabilizers, reaching its maximum at equivalent weight ratio of the investigated stabilizer to the reference one. J. VINYL ADDIT. TECHNOL., 22:247-258, 2016. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A simple, rapid, and efficient ultrasound-assisted emulsification microextraction method followed by gas chromatography mass spectrometry in selected ion monitoring mode was developed for the determination of organochlorine pesticides in honey samples. The type and volume of organic extraction solvent, pH, effect of added salt content, and centrifuging time and speed were investigated. Under the optimum extraction conditions, 30 μL of 1, 2-dibromoethane (extraction solvent) was immersed into an ultrasonic bath for 1 min at 40°C. The limits of detection and quantification for all target pesticides were 0.003-0.06 and 0.01-0.2 ng/g, respectively. The extraction recovery was 91-100% and the enrichment factors were 168-192. The relative standard deviation for the method was <6% for intraday ( n = 6) and <8% for interday precision ( n = 4). The proposed method was successfully applied for the analysis of organochlorine pesticides in honey samples. [ABSTRACT FROM AUTHOR]

The development of dicamba (3,6-dichloro-2-methoxybenzoic acid)- and 2,4-D [(2,4-dichlorophenoxy) acetic acid]-resistant soybean [Glycine max (L.) Merr.] will increase the frequency of applying these herbicides to control broadleaf weeds in soybean production systems. We evaluated the sensitivity of randomly selected waterhemp [Amaranthus tuberculatus (Moq.) Sauer var. rudis (Sauer) Costea and Tardif] and Palmer amaranth (Amaranthuspalmeri S. Wats) populations to a single dose of dicamba and 2,4-D. Selected populations were then used in dicamba and 2,4-D dose-response experiments to evaluate: (i) visual injury at 28 d after treatment; and (ii) plant survival, biomass accumulation, and flowering at 84 DAT. Across selected populations, the estimated dicamba dose for 50% visual injury (I50) was below the recommended field rate (560 g ha-1) and ranged between 59 and 117 g ha-1 for waterhemp and 43 and 81 g ha-1 for Palmer amaranth populations. The estimated 2,4-D dose for I50 was also below the recommended field rate (800 g ha-1) and ranged between 127 and 242 g ha-1 for waterhemp and 127 and 196 g ha-1 for Palmer amaranth. Waterhemp plants flowered with up to 560 g ha-1 dicamba and 2240 g ha-1 2,4-D, while Palmer amaranth plants flowered with up to 280 g ha-1 dicamba, and 1120 g ha-1 2,4-D. Individual plants will likely survive and flower following recommended field rates of dicamba (waterhemp) and 2,4-D (both species). Close monitoring of weed populations are needed for the stewardship of available weed management technologies. [ABSTRACT FROM AUTHOR]

Hydrodechlorination is a promising method for treating toxic chlorocarbon compounds. Pd is among the most effective catalysts for chloroform hydrodechlorination, and experiments have shown that the Pd-Au alloy catalyst yields superior catalytic performance over pure Pd. Here we examine the chloroform hydrodechlorination mechanism over Pd(1 1 1) and PdML/Au(1 1 1) surfaces using periodic, self-consistent density functional theory calculations (DFT, GGA-PW91) and maximum rate analysis. We suggest that the reaction occurs on both surfaces through complete dechlorination of chloroform followed by hydrogenation of CH* to methane, and that the initial dechlorination step is likely the rate-limiting step. On Pd(1 1 1), the chloroform dechlorination barrier is 0.24 eV higher than the desorption barrier, whereas on PdML/Au(1 1 1), the chloroform dechlorination barrier is 0.07 eV lower than the desorption barrier, which can explain the higher hydrodechlorination activity of the Pd-Au alloy catalyst. [ABSTRACT FROM AUTHOR]

BACKGROUND The pangasius catfish ( Pangasianodon hypophthalmus) is a ubiquitous item of seafood in global markets. However, pesticide residues in aquaculture fish, arising from agricultural run-off and/or direct application during pond preparation, pest control and harvest, are a potential food safety concern. This study assessed the level of chemical hazard in domestic and imported pangasius fish in India. RESULTS A total of 119 contaminants, including polyaromatic hydrocarbons ( PAHs), organochlorines ( OCs) and other groups of pesticides, were screened in 148 samples during 2014-2015 as the first endeavour of its kind in an Indian context, employing a validated gas chromatography/tandem mass spectrometry ( GC/ MS/ MS) method. Apart from the low-level incidence of OCs, pesticides such as quinalphos, malathion, parathion-methyl, etc. were detected in 38% of the samples. In comparison with Indian pangasius, fewer contaminants at low residue level were detected in pangasius fillets imported from Vietnam. CONCLUSION The human dietary exposures of the residue concentrations detected were less than the maximum permissible intakes and hence appeared safe. However, detection of commonly used pesticides indicated their direct application in aquaculture and contamination from agricultural run-off. This emphasizes the need for continual residue monitoring in aquaculture fish. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Concentrations, pollutant characteristics and sources apportionment of organic pesticides (OPs) of fifty one soils from bamboo forest in Zhejiang province, China were investigated. Ten organochlorine(OCPs), three organophosphorus(OPPs), and one pyrethroids (OPYs) were detected. The detection rate (DR %) ranged from 27.27% to 100%, and descended in the order: OCPs>OPPs>OPYs. Concentrations of all OCPs and OPPs were <15µg kg-1, while the concentrations of hexachlorocyclohexane (HCH) and 1,1,1-tri-chloro-2,2-di(4-chlorophenyl)ethane (DDT) were <50 µg kg-1, and no recent usage. However, fenvalerate(FEN) had a concentration of 1227 µg kg-1, the maximal value of all OPs. OPs residue in soil with pH 3.10 - 4.50 was nearly higher than those of soil with pH 4.51 - 5.90. OCPs residue was positive correlated with soil TOC, while OPPs and OPYs residue were influenced markedly by usage and management intensity. The DR %, peak value and ratio of excess standard for methamidophos (MEA) was 82.35%, 33.62 µg kg-1 and 82.35%, respectively. The residue levels of MEA accounted for 70.87% of the σ-OPPS and significantly positively correlated with σ-OPPS. All results was summarized that OPPs, OPYs and partial of OCPs such as Chlorothalonil (CHL), Dicofol (DIC) was main pollutant and potential to jeopardize the human health, bamboo forest environment and shoot production. [ABSTRACT FROM AUTHOR]

Recent government mandates have lowered the permissible global warming potential (GWP) for refrigerants in mobile air conditioning substantially below that of the hydrofluorocarbon products that are used currently. Potential replacements, hydrofluoro-olefins (HFO), have a reduced impact on the ozone layer and lower GWP. Many desirable HFO compounds, such as HFO-1234yf, can be produced utilizing chlorocarbons as feedstocks such as the preferred 1,1,2,3-tetrachloropropene (TCPE). TCPE can be produced by several routes; however, producing TCPE from 1,2-dichloropropane (PDC) is potentially more desirable environmentally and economically since PDC is a byproduct of propylene oxide and allyl chloride production. One process option is to convert PDC to pentachloropropane (PCP) intermediates by chlorination, followed by dehydrochlorination of the PCPs to produce TCPE. In this work, we show that PCPs can be produced through the chlorination of PDC in a free-radical liquid phase reaction and have developed a kinetic model for PDC chlorination based on the relevant free radical elementary reactions. Thermodynamic properties including standard heats of formation, standard entropies of formation, and heat capacities for the radical and non-radical species were estimated by using ab initio and COSMOtherm calculations and validated against available experimental data. The reaction equilibrium constants were determined from the Gibb's free energies of the reactants and products. Phase equilibria were calculated by means of a consistent set of thermodynamic properties of the species. In addition, physical properties such as the vapor pressure of pure components involved in the reaction network were also estimated. Ab initio transition state calculations were employed to estimate the rate parameters including pre-exponential factors and activation energies for the relevant reactions. The activation energies of some key reactions were then adjusted to match experimental data. The resulting kinetic model provided a basis for process yield optimization and scale up. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1174-1191, 2016 [ABSTRACT FROM AUTHOR]

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) residues were studied in different mollusk species from the Egyptian Mediterranean and Red Sea coasts. The average levels of OCPs in mollusks comprised chlordanes, dieldrins, total endrin, endosulfan compounds, and methoxychlor (DECEM), dichlorodiphenyltrichloroethanes (DDTs), and, hexachlorocyclohexanes (HCHs). The averages of HCHs, DDTs, and polychlorinated biphenyls (PCBs) in mollusks from the Mediterranean Sea were 1.13 ± 1.21, 1.30 ± 1.27, and 1.40 ± 0.93 ng/g, respectively; from the Red Sea, they were 0.62 ± 0.90, 1.77 ± 1.82, and 6.44 ± 5.05 ng/g, respectively. The analysis of HCHs, DDTs, and PCBs in mollusks indicates a new usage of lindane, PCB congeners, and the input of technical HCH and aged DDT. The data showed that the Red Sea Coast was more affected by PCBs congeners than the Mediterranean Sea Coast, which may be attributed to the different activities along the two coastal areas. Mollusks in the Mediterranean Sea had higher dieldrins, total endrin, endosulfan compounds, and methoxychlor contents than those in the Red Sea. Interestingly, HCHs, DDTs, and PCBs levels were lower than those recommended for Swedish Food Regulation and U.S. Food and Drug Administration, which means that mollusks from these two coastal areas are safe as food. [ABSTRACT FROM AUTHOR]

Organochlorine insecticides have been studied extensively in relation to breast cancer incidence, and results from two metaanalyses have been null for late-life residues, possibly due to measurement error. Whether these compounds influence survival remains to be fully explored. We examined associations between organochlorine insecticides [p,p0-DDT (dichlorodiphenyltrichloroethane), its primary metabolite, p,p0-DDE, and chlordane] assessed shortly after diagnosis and survival among women with breast cancer. A population-based sample of women diagnosed with a first primary invasive or in situ breast cancer in 1996-1997 and with available organochlorine blood measures (n5633) were followed for vital status through 2011. After follow-up of 5 and 15 years, we identified 55 and 189 deaths, of which 36 and 74, respectively, were breast cancer-related. Using Cox regression models, we estimated the multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for lipid-adjusted organochlorine concentrations with all-cause and breast cancer-specific mortality. At 5 years after diagnosis, the highest tertile of DDT concentration was associated with all-cause (HR52.19; 95% CI: 1.02, 4.67) and breast cancerspecific (HR52.72; 95% CI: 1.04, 7.13) mortality. At 15 years, middle tertile concentrations of DDT (HR51.42; 95% CI 0.99, 2.06) and chlordane (HR51.42; 95% CI: 0.94, 2.12) were modestly associated with all-cause and breast cancer-specific mortality. Third tertile DDE concentrations were inversely associated with 15-year all-cause mortality (HR50.66; 95% CI: 0.44, 0.99). This is the first population-based study in the United States to show that DDT may adversely impact survival following breast cancer diagnosis. Further studies are warranted given the high breast cancer burden and the ubiquity of these chemicals. [ABSTRACT FROM AUTHOR]

Trace analysis of chlorophenols in water was performed by simultaneous silylation and dispersive liquid-liquid microextraction followed by gas chromatography with mass spectrometry. Dispersive liquid-liquid microextraction was carried out using an organic solvent lighter than water ( n-hexane). The effect of different silylating reagents on the method efficiency was investigated. The influence of derivatization reagent volume, presence of catalyst and derivatization/extraction time on the yield of the derivatization reaction was studied. Different parameters affecting extraction efficiency such as kind and volume of extraction and disperser solvents, pH of the sample and addition of salt were also investigated and optimized. Under the optimum conditions, the calibration graphs were linear in the range of 0.05-100 ng/mL and the limit of detection was 0.01 ng/mL. The enrichment factors were 242, 351, and 363 for 4-chlorophenol, 2,4-dichlorophenol, and 2,4,6-trichlorophenol, respectively. The values of intra- and inter-day relative standard deviations were in the range of 3.0-6.4 and 6.1-9.9%, respectively. The applicability of the method was investigated by analyzing water and wastewater samples. [ABSTRACT FROM AUTHOR]

We demonstrate the potential of infrared degenerate four-wave mixing (IR-DFWM) as a tool for non-intrusive in situ spatially resolved detection of CH3Cl in reactive hot gas flows especially feasible for applications to biomass combustion and gasification. IR-DFWM spectra of CH3Cl, by probing ro-vibrational transitions belonging to the fundamental stretching modes v1 and v4, have been successfully recorded in gas flows diluted with nitrogen at atmospheric pressure and elevated temperatures up to 820 K. In order to identify the spectral lines of CH3Cl, the recorded IR-DFWM spectra are compared with simulations using molecular parameters extracted from the HITRAN database. The potential interference from water vapor is discussed from measurements of H2O spectrum at 820 K combined with simulations of H2O IR-DFWM spectrum based on the HITEMP database, and it was found that the QQ6 line of the v1 band is relatively free from water interference at elevated temperatures. At atmospheric pressure, the detection limits for temperatures at 296, 550 and 820 K were estimated to be 2.1, 3.1 and 6.2 (×1015 molecules/cm3), respectively, by scanning the QQ6 line of the v1 band. These results show the potential of interference free detection of CH3Cl with IR-DFWM in harsh environments like combustion. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

RATIONALE: The development of compound-specific chlorine isotope analysis (Cl-CSIA) is hindered by the lack of international organochlorine reference materials with isotopic compositions expressed in the δ37Cl notation. Thus, a reliable off-line analytical method is needed, allowing direct comparison of the δ37Cl values of molecularly different organic compounds with that of ocean-water chloride, to refer measurement results to a Standard Mean Ocean Chloride (SMOC) scale. METHODS: The analytical method included sealed-tube combustion of organochlorines, precipitation and subsequent conversion of formed inorganic chlorides into methyl chloride (CH3Cl) for the determination of δ37Cl values by Dual- Inlet Isotope Ratio Mass Spectrometry (DI-IRMS). A sample preparation step most sensitive to the sample size - dissolution of the inorganic copper chlorides formed by combustion of organochlorines - was identified. RESULTS: Recovery of 94 ±5% of chlorine was reached by applying determined optimal conditions for the dissolution, implying good external precision of δ37Cl values (-0.18 ± 0.03‰, 1σ, n = 3). Validation of the optimized method by the analysis of the produced and initial CH3Cl samples with known δ37Cl values vs SMOC resulted in a difference of 0.11 ± 0.04‰ (1σ, n=3), confirming the external precision and accuracy of the entire method. CONCLUSIONS: The efficiency of the sample preparation method for CH3Cl-DI-IRMS analysis is independent both of the chemical structure of the chlorinated compound and of the amount of chlorine in the sample. This method has the potential to be applied to a broad range of chlorinated organic compounds, e.g. reference material for the calibration of methods for Cl-CSIA against SMOC. [ABSTRACT FROM AUTHOR]

Caged supramolecular systems are promising hosts for guest inclusion, separation, and stabilization. Well-studied examples are mainly metal-coordination-based or covalent architectures. An anion-coordination-based cage that is capable of encapsulating halocarbon guests is reported for the first time. This A4L4-type (A=anion) tetrahedral cage, [(PO4)4 L4]12−, assembled from a C3-symmetric tris(bisurea) ligand ( L) and phosphate ion (PO43−), readily accommodates a series of quasi-tetrahedral halocarbons, such as the Freon components CFCl3, CF2Cl2, CHFCl2, and C(CH3)F3, and chlorocarbons CH2Cl2, CHCl3, CCl4, C(CH3)Cl3, C(CH3)2Cl2, and C(CH3)3Cl. The guest encapsulation in the solid state is confirmed by crystal structures, while the host-guest interactions in solution were demonstrated by NMR techniques. [ABSTRACT FROM AUTHOR]

A large industrial water resource recovery facility needed to significantly reduce the amount of 1,2-dichlorobenzene (ODCB) entering its biological treatment units. Numerous Advanced Oxidation Processes (AOPs) were considered based on literature and industry reports. Many AOPs appear to be incompatible with some of the native species present in groundwater or wastewater matrices. Iron, in particular, is often viewed as a nuisance increasing the complexity of the overall treatment scheme. The approach used in the current study was to incorporate the new AOP into the existing groundwater matrix and facilities as much as possible. To that end, native iron was exploited as the reaction catalyst, an acid was selected to fit with current macro nutrient needs of the biotreatment units, and the reactor was designed to require minimum modification of the existing facilities. The ''green chemical'' (Noyori, 2003) treatment process selected was demonstrated at full-scale, achieving good agreement with the results of prior laboratory studies. Up to eighty percent destruction of ODCB was demonstrated in a new pretreatment unit whose effluent fit seamlessly with the existing bioreactors. [ABSTRACT FROM AUTHOR]

A highly sensitive surface-enhanced Raman scattering (SERS) platform for the selective trace analysis of persistent organic pollutant (POP) such as polychlorinated biphenyl (PCBs) was reported based on β-CD modified gold nanoparticles (AuNPs) with the real environmental sample of polluted soil. The synthesized gold nanoparticles were characterized using UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). In polluted soil the presentation of PCB is confirmed by using GC-MS. It is further verified and confirmed by using SERS. When the contaminated soil was added to the system, the binding of soil with β-CD resulted in the aggregation of AuNPs, and excellent Raman signal was obtained which can reflect the isomers of polychlorinated biphenyls. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel procedure of sample preparation combined with high-performance liquid chromatography with diode array detection is introduced for the analysis of highly chlorinated phenols (trichlorophenols, tetrachlorophenols, and pentachlorophenol) in wine. The main features of the proposed method are (i) low-toxicity diethyl carbonate as extraction solvent to selectively extract the analytes without matrix effect, (ii) the combination of salting-out assisted liquid-liquid extraction and dispersive liquid-liquid microextraction to achieve an enrichment factor of 334-361, and (iii) the extract is analyzed by high-performance liquid chromatography to avoid derivatization. Under the optimum conditions, correlation coefficients ( r) were >0.997 for calibration curves in the range 1-80 ng/mL, detection limits and quantification limits ranged from 0.19 to 0.67 and 0.63 to 2.23 ng/mL, respectively, and relative standard deviation was <8%. The method was applied for the determination of chlorophenols in real wines, with recovery rates in the range 82-104%. [ABSTRACT FROM AUTHOR]

ABSTRACT Dexamethasone-loaded poly(lactide- co-glycolide) (PLGA) devices are commonly used as model systems for controlled release. In this study, PLGA nanoparticles containing dexamethasone acetate were prepared by a nanoprecipitation technique in the absence of organochlorine solvents and were characterized by their mean size, ζ potential, scanning electron microscopy, and differential scanning calorimetry to develop a controlled release system. The analytical method for the quantification of dexamethasone acetate by high-performance liquid chromatography was validated. The results show that it was possible to prepare particles at a nanometric size because the average diameter of the drug-loaded PLGA particles was 540 ± 4 nm with a polydispersity index of 0.07 ± 0.01 and a ζ potential of −2.5 ± 0.3 mV. These values remained stable for at least 7 months. The drug encapsulation efficiency was 48%. In vitro tests showed that about 25% of the drug was released in 48 h. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41199. [ABSTRACT FROM AUTHOR]

Objective To demonstrate the protection of Merino sheep from flystrike by Lucilia cuprina with cyromazine or dicyclanil in an implant study and in the field. Methods In the implant study, sheep were treated with cyromazine or dicyclanil and implanted with 1st-stage larvae from a newly isolated field strain of L. cuprina ( CYR-LS) or a reference strain ( DZR50), then assessed over 3 days and compared with the implants on untreated control sheep. In the field study, weaner lambs were treated with cyromazine or dicyclanil and monitored weekly for flystrike over 18 weeks of grazing on the same farm from which the L. cuprina were isolated. Results Implant study: cyromazine (6%) provided effective protection against CYR-LS and DZR50 L. cuprina for a minimum of 13 and 10 weeks, respectively. Dicyclanil (5%) provided at least 18 weeks' protection against both strains. Field study: only 1 of 386 lambs in the cyromazine-treated group was struck in the first 14 weeks of the trial. No strikes occurred in the 198 sheep treated with dicyclanil (5%). Rainfall, temperature and flytrap data indicated consistent fly pressure during the study. Conclusions Based on the results of these studies, there was no evidence of reduced susceptibility to cyromazine or dicyclanil and the periods of protection of sheep against L. cuprina were unaffected and consistent with the registered label claims. [ABSTRACT FROM AUTHOR]

A novel fast screening method was developed for the determination of polychlorinated biphenyls that are constituents of the commercial mixture, Aroclor 1260, in soil matrices by gas chromatography with mass spectrometry combined with solid-phase microextraction. Nonequilibrium headspace solid-phase microextraction with a 100 μm polydimethylsiloxane fiber was used to extract polychlorinated biphenyls from 0.5 g of soil matrix. The use of 2 mL of saturated potassium dichromate in 6 M sulfuric acid solution improved the reproducibility of the extractions and the mass transfer of the polychlorinated biphenyls from the soil matrix to the microextraction fiber via the headspace. The extraction time was 30 min at 100°C. The percent recoveries, which were evaluated using an Aroclor 1260 standard and liquid injection, were within the range of 54.9-65.7%. Two-way extracted ion chromatogram data were used to construct calibration curves. The relative error was <±15% and the relative standard deviation was <15%, which are respective measures of the accuracy and precision. The method was validated with certified soil samples and the predicted concentrations for Aroclor 1260 agreed with the certified values. The method was demonstrated to be linear from 10 to 1000 ng/g for Aroclor 1260 in dry soil. [ABSTRACT FROM AUTHOR]

A simple, rapid, efficient, and environmentally friendly pretreatment based on a low-density solvent based dispersive liquid-liquid microextraction was developed for determining trace levels of 17 organochlorine pesticides in snow. The parameters affecting the extraction efficiency, such as the type and volume of the extraction and dispersive solvents, extraction time, and salt content, were optimized. The optimized conditions yielded a good performance, with enrichment factors ranging from 271 to 474 and recoveries ranging from 71.4 to 114.5% and relative standard deviations between 1.6 and 14.8%. The detection limits, calculated as three times the signal-to-noise ratio, ranged from 0.02 to 0.11 μg/L. The validated method was used to successfully analyze 17 analytes in snow water samples, overcoming the drawbacks of some existing low-density solvent liquid microextraction methods, which require special devices, large volumes of organic solvents, or complicated operation procedures. [ABSTRACT FROM AUTHOR]

Biosolids are an important source of nutrients and organic matter, which are necessary for the productive cultivation of crop plants. Biosolids have been found to contain the personal care products triclosan and triclocarban at high concentrations relative to other pharmaceuticals and personal care products. The present study investigates whether exposure of 6 plant species (radish, carrot, soybean, lettuce, spring wheat, and corn) to triclosan or triclocarban derived from biosolids has an adverse effect on seed emergence and/or plant growth parameters. Plants were grown in soil amended with biosolids at a realistic agronomic rate. Biosolids were spiked with triclosan or triclocarban to produce increasing environmentally relevant exposures. The concentration of triclosan and triclocarban in biosolids-amended soil declined by up to 97% and 57%, respectively, over the course of the experiments. Amendment with biosolids had a positive effect on the majority of growth parameters in radish, carrot, soybean, lettuce, and wheat plants. No consistent triclosan- or triclocarban-dependent trends in seed emergence and plant growth parameters were observed in 5 of 6 plant species. A significant negative trend in shoot mass was observed for lettuce plants exposed to increasing concentrations of triclocarban ( p < 0.001). If best management practices are followed for biosolids amendment, triclosan and triclocarban pose a negligible risk to seed emergence and growth of crop plants. Environ Toxicol Chem 2014;33:1840-1848. © 2014 SETAC [ABSTRACT FROM AUTHOR]