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Mercury risk assessment combining internal and external exposure methods for a population living near a municipal solid waste incinerator Texte intégral
2016
Deng, Chunyan | Xie, Han | Ye, Xuejie | Zhang, Haoran | Liu, Maodian | Tong, Yindong | Ou, Langbo | Yuan, Wen | Zhang, Wei | Wang, Xuejun
Risk assessments for human health have been conducted for municipal solid waste incinerators (MSWIs) in many western countries, whereas only a few risk assessments have been performed for MSWIs in developing countries such as China where the use of waste incineration is increasing rapidly. To assess the mercury exposure risks of a population living near the largest MSWI in South China, we combined internal exposure and external exposure assessment with an individual–specific questionnaire. The mercury concentrations in air, soil, and locally collected food around the MSWI were assessed. The total mercury (T-Hg) and methylmercury (MeHg) of 447 blood samples from a control group, residential exposure group, and MSWI workers were measured. The internal and external exposures of the subject population were analyzed. Significant difference in MeHg concentrations was observed between the control group and the exposed group, between the control group and the MSWI workers, and between the exposed group and the MSWI workers (median levels: 0.70 μg/L, 0.81 μg/L, and 1.02 μg/L for the control group, exposed group, and MSWI workers, respectively). The MeHg/T-Hg ratio was 0.51 ± 0.19, 0.59 ± 0.17 and 0.58 ± 0.25, respectively. Multiple linear regression analysis indicated that MeHg concentrations were positively correlated with the gaseous mercury in the air. Combining internal and external exposure assessment showed that the direct contribution of MSWI emissions was minor compared with the dietary contribution. The external and internal exposures were well matched with each other. This study also suggested that an integrated method combining internal and external exposure assessment with an individual–specific questionnaire is feasible to assess the risks for a population living near a MSWI.
Afficher plus [+] Moins [-]Palaeo-pollution from mining activities in the Vosges Mountains: 1000 years and still bioavailable Texte intégral
2016
Mariet, Anne-Lise | de Vaufleury, Annette | Bégeot, Carole | Walter-Simonnet, Anne-Véronique | Gimbert, Frédéric
Palaeo-pollution from mining activities in the Vosges Mountains: 1000 years and still bioavailable Texte intégral
2016
Mariet, Anne-Lise | de Vaufleury, Annette | Bégeot, Carole | Walter-Simonnet, Anne-Véronique | Gimbert, Frédéric
Mining and smelting activities have contaminated the environment with trace metals (TMs) at a worldwide scale for at least two millennia. A combination of chemical approaches and active biomonitoring was performed to analyse the environmental availability and bioavailability of TM palaeo-pollution in a former PbAg mining district in the Vosges Mountains, France. Along a soil TM contamination gradient that covered eight stations, including two archaeological mining sites, the toxicokinetics of six TMs (Pb, Cd, As, Ag, Co, Sb) in the snail Cantareus aspersus revealed that palaeo-pollution from the studied sites remains bioavailable. This study provides the first data on the accumulation kinetics of Ag and Co for C. aspersus. The environmental availability of the TMs was estimated with three chemical extraction methods (aqua regia, EDTA 50 mM, CaCl2 10 mM). Univariate regression analyses showed that EDTA extraction is the best method for estimating the bioavailability of Pb, As, Ag, Co and Sb to snails. None of the three extractants was efficient for Cd. A multivariate analysis of bioaccumulation data revealed that TM bioavailability and transfer were modulated by exposure sources (soil, humus and vegetation) rather than by soil physico-chemical characteristics. Hence, although the deposition of mining wastes dates back several centuries, these wastes still represent a source of contamination that must be considered to develop relevant site management and environmental risk assessment.
Afficher plus [+] Moins [-]Palaeo-pollution from mining activities in the Vosges Mountains: 1000 years and still bioavailable Texte intégral
2016
Mariet, Anne-Lise | de Vaufleury, Annette | Bégeot, Carole | Walter-Simonnet, Anne-Véronique | Gimbert, Frédéric | Université Bourgogne Franche-Comté [COMUE] (UBFC) | Funding Agency and Grant Number : French "Agence de l'Environnement et de la Maitrise de l'Energie" (ADEME); Conseil Regional de Franche-Comte; University of Franche-Comte (BQR PRES); French national program EC2CO-Ecodyn (POLMIN); University of Bourgogne (BQR PRES)
International audience | Mining and smelting activities have contaminated the environment with trace metals (TMs) at a worldwide scale for at least two millennia. A combination of chemical approaches and active biomonitoring was performed to analyse the environmental availability and bioavailability of TM palaeo-pollution in a former Pb-Ag mining district in the Vosges Mountains, France. Along a soil TM contamination gradient that covered eight stations, including two archaeological mining sites, the toxicokinetics of six TMs (Pb, Cd, As, Ag, Co, Sb) in the snail Cantareus aspersus revealed that palaeo-pollution from the studied sites remains bioavailable. This study provides the first data on the accumulation kinetics of Ag and Co for C. aspersus. The environmental availability of the TMs was estimated with three chemical extraction methods (aqua regia, EDTA 50 mM, CaCl2 10 mM). Univariate regression analyses showed that EDTA extraction is the best method for estimating the bioavailability of Pb, As, Ag, Co and Sb to snails. None of the three extractants was efficient for Cd. A multivariate analysis of bioaccumulation data revealed that TM bioavailability and transfer were modulated by exposure sources (soil, humus and vegetation) rather than by soil physico-chemical characteristics. Hence, although the deposition of mining wastes dates back several centuries, these wastes still represent a source of contamination that must be considered to develop relevant site management and environmental risk assessment. (C) 2016 Elsevier Ltd. All rights reserved.
Afficher plus [+] Moins [-]Alterations in juvenile diploid and triploid African catfish skin gelatin yield and amino acid composition: Effects of chlorpyrifos and butachlor exposures Texte intégral
2016
Karamī, ʻAlī | Karbalaei, Samaneh | Zad Bagher, Fariba | Ismail, Amin | Simpson, Stuart L. | Courtenay, Simon C.
Skin is a major by-product of the fisheries and aquaculture industries and is a valuable source of gelatin. This study examined the effect of triploidization on gelatin yield and proximate composition of the skin of African catfish (Clarias gariepinus). We further investigated the effects of two commonly used pesticides, chlorpyrifos (CPF) and butachlor (BUC), on the skin gelatin yield and amino acid composition in juvenile full-sibling diploid and triploid African catfish. In two separate experiments, diploid and triploid C. gariepinus were exposed for 21 days to graded CPF [mean measured: 10, 16, or 31 μg/L] or BUC concentrations [Mean measured: 22, 44, or 60 μg/L]. No differences in skin gelatin yield, amino acid or proximate compositions were observed between diploid and triploid control groups. None of the pesticide treatments affected the measured parameters in diploid fish. In triploids, however, gelatin yield was affected by CPF treatments while amino acid composition remained unchanged. Butachlor treatments did not alter any of the measured variables in triploid fish. To our knowledge, this study is the first to investigate changes in the skin gelatin yield and amino acid composition in any animal as a response to polyploidization and/or contaminant exposure.
Afficher plus [+] Moins [-]Industrial water pollution, water environment treatment, and health risks in China Texte intégral
2016
Wang, Qing | Yang, Zhiming
The negative health effects of water pollution remain a major source of morbidity and mortality in China. The Chinese government is making great efforts to strengthen water environment treatment; however, no studies have evaluated the effects of water treatment on human health by water pollution in China. This study evaluated the association between water pollution and health outcomes, and determined the extent to which environmental regulations on water pollution may lead to health benefits. Data were extracted from the 2011 and 2013 China Health and Retirement Longitudinal Study (CHARLS). Random effects model and random effects Logit model were applied to study the relationship between health and water pollution, while a Mediator model was used to estimate the effects of environmental water treatment on health outcomes by the intensity of water pollution. Unsurprisingly, water pollution was negatively associated with health outcomes, and the common pollutants in industrial wastewater had differential impacts on health outcomes. The effects were stronger for low-income respondents. Water environment treatment led to improved health outcomes among Chinese people. Reduced water pollution mediated the associations between water environment treatment and health outcomes. The results of this study offer compelling evidence to support treatment of water pollution in China.
Afficher plus [+] Moins [-]Dissolved organic carbon content and characteristics in relation to carbon dioxide partial pressure across Poyang Lake wetlands and adjacent aquatic systems in the Changjiang basin Texte intégral
2016
Wang, Huaxin | Jiao, Ruyuan | Wang, Fang | Zhang, Lu | Yan, Weijin
Dissolved organic carbon (DOC) plays diverse roles in carbon biogeochemical cycles. Here, we explored the link between DOC and pCO2 using high-performance size-exclusion chromatography (HPSEC) with UV254 detection and excitation emission matrix (EEM) fluorescence spectroscopy to determine the molecular weight distribution (MW) and the spectral characteristics of DOC, respectively. The relationship between DOC and pCO2 was investigated in the Poyang Lake wetlands and their adjacent aquatic systems. The results indicated significant spatial variation in the DOC concentrations, MW distributions, and pCO2. The DOC concentration was higher in the wetlands than in the rivers and lakes. pCO2 was high in wetlands in which the dominant vegetation was Phragmites australis, whereas it was low in wetlands in which Carex tristachya was the dominant species. DOC was divided into five fractions according to MW, as follows: super-low MW (SLMW, <1 kDa); low MW (LMW, 1–2.5 kDa); intermediate MW (IMW, 2.5–3.5 kDa); high MW (HMW, 3.5–6 kDa); and super-high MW (SMW, > 40 kDa). Rivers contained high proportions of HMW and extremely low amounts of SLMW, whereas wetlands had relatively high proportions of SLMW. The proportion of SMW (SMWp) was particularly high in wetlands. We found that pCO2 significantly positively correlated with the proportion of IMW, and significantly negatively correlated with SMWp. These data improve our understanding of the MW of bioavailable DOC and its conversion to CO2. The present results demonstrate that both the content and characteristics of DOC significantly affect pCO2. pCO2 and DOC must be studied further to help understanding the role of the wetland on the regional CO2 budget.
Afficher plus [+] Moins [-]Winter monsoon variability and its impact on aerosol concentrations in East Asia Texte intégral
2016
Jeong, Jaein I. | Park, Rokjin J.
We investigate the relationship between winter aerosol concentrations over East Asia and variability in the East Asian winter monsoon (EAWM) using GEOS-Chem 3-D global chemical transport model simulations and ground-based aerosol concentration data. We find that both observed and modeled surface aerosol concentrations have strong relationships with the intensity of the EAWM over northern (30–50°N, 100–140°E) and southern (20–30°N, 100–140°E) East Asia. In strong winter monsoon years, compared to weak winter monsoon years, lower and higher surface PM2.5 concentrations by up to 25% are shown over northern and southern East Asia, respectively. Analysis of the simulated results indicates that the southward transport of aerosols is a key process controlling changes in aerosol concentrations over East Asia associated with the EAWM. Variability in the EAWM is found to play a major role in interannual variations in aerosol concentrations; consequently, changes in the EAWM will be important for understanding future changes in wintertime air quality over East Asia.
Afficher plus [+] Moins [-]Towards the suitable monitoring of ingestion of microplastics by marine biota: A review Texte intégral
2016
Wesch, Charlotte | Bredimus, Katja | Paulus, Martin | Klein, Roland
Monitoring plastic ingestion in marine biota is a difficult task, especially regarding ubiquitous microplastics (particles of <5 mm). Due to their microscopic size, evidence for microplastic ingestion is often limited to laboratory studies. The following review provides a comparison and assessment of different microplastic ingestion monitoring procedures. Emphasis is given to the most important steps of current monitoring practice: (1) selecting suitable indicator species, (2) sampling and sample processing, (3) analytical procedures and (4) the prevention of secondary contamination of the sample. Moreover, an overview on ingestion records of microplastics by different marine feeding guilds is presented, including filter, suspension and deposit feeders as well as predators and scavengers. Lastly, monitoring processes are addressed critically in terms of their suitability for achieving the aims of an appropriate monitoring programme. Recommendations for future research priorities are presented with a focus on the necessity of standardised and comparable monitoring procedures in microplastic detection.
Afficher plus [+] Moins [-]Predicting chronic copper and nickel reproductive toxicity to Daphnia pulex-pulicaria from whole-animal metabolic profiles Texte intégral
2016
Taylor, Nadine S. | Kirwan, Jennifer A. | Johnson, Craig | Yan, Norman D. | Viant, Mark R. | Gunn, John M. | McGeer, James C.
The emergence of omics approaches in environmental research has enhanced our understanding of the mechanisms underlying toxicity; however, extrapolation from molecular effects to whole-organism and population level outcomes remains a considerable challenge. Using environmentally relevant, sublethal, concentrations of two metals (Cu and Ni), both singly and in binary mixtures, we integrated data from traditional chronic, partial life-cycle toxicity testing and metabolomics to generate a statistical model that was predictive of reproductive impairment in a Daphnia pulex-pulicaria hybrid that was isolated from an historically metal-stressed lake. Furthermore, we determined that the metabolic profiles of organisms exposed in a separate acute assay were also predictive of impaired reproduction following metal exposure. Thus we were able to directly associate molecular profiles to a key population response – reproduction, a key step towards improving environmental risk assessment and management.
Afficher plus [+] Moins [-]Manganese concentrations in drinking water from villages near banana plantations with aerial mancozeb spraying in Costa Rica: Results from the Infants' Environmental Health Study (ISA) Texte intégral
2016
van Wendel de Joode, Berna | Barbeau, Benoit | Bouchard, Maryse F. | Mora, Ana María | Skytt, Åsa | Córdoba, Leonel | Quesada, Rosario | Lundh, Thomas | Lindh, Christian H. | Mergler, Donna
Elevated manganese (Mn) in drinking water has been reported worldwide. While, naturally occurring Mn in groundwater is generally the major source, anthropogenic contamination by Mn-containing fungicides such as mancozeb may also occur. The main objective of this study was to examine factors associated with Mn and ethylenethiourea (ETU), a degradation product of mancozeb, in drinking water samples from villages situated near banana plantations with aerial spraying of mancozeb. Drinking water samples (n = 126) were obtained from 124 homes of women participating in the Infants' Environmental Health Study (ISA, for its acronym in Spanish), living nearby large-scale banana plantations. Concentrations of Mn, iron (Fe), arsenic (As), lead (Pb), cadmium (Cd) and ethylenethiourea (ETU), a degradation product of mancozeb, were measured in water samples. Only six percent of samples had detectable ETU concentrations (limit of detection (LOD) = 0.15 μg/L), whereas 94% of the samples had detectable Mn (LOD = 0.05 μg/L). Mn concentrations were higher than 100 and 500 μg/L in 22% and 7% of the samples, respectively. Mn was highest in samples from private and banana farm wells. Distance from a banana plantation was inversely associated with Mn concentrations, with a 61.5% decrease (95% CI: −97.0, −26.0) in Mn concentrations for each km increase in distance. Mn concentrations in water transported with trucks from one village to another were almost 1000 times higher than Mn in water obtained from taps in houses supplied by the same well but not transported, indicating environmental Mn contamination. Elevated Mn in drinking water may be partly explained by aerial spraying of mancozeb; however, naturally occurring Mn in groundwater, and intensive agriculture may also contribute. Drinking water risk assessment for mancozeb should consider Mn as a health hazard. The findings of this study evidence the need for health-based World Health Organization (WHO) guidelines on Mn in drinking water.
Afficher plus [+] Moins [-]Distribution of polychlorinated biphenyls, phthalic acid esters, polycyclic aromatic hydrocarbons and organochlorine substances in the Moscow River, Russia Texte intégral
2016
Eremina, Natalia | Paschke, Albrecht | Mazlova, Elena A. | Schüürmann, Gerrit
The purpose of this study was to investigate the levels of polychlorinated biphenyl (PCB), phthalic acid esters (PAE), polycyclic aromatic hydrocarbons (PAH) and organochlorine substances (OCP) in the Moscow River water. Some studies have reported the occurrence of these substances in the soil of the Moscow region; however, no study has yet established an overview for these compounds in the Moscow River water. In this study the Moscow River water contamination with PAEs, PAHs and OCPs was determined. Obtained results were associated with the resident area located on the river bank, and the possible contamination sources were considered. The obtained data were compared with the data on the contamination of the different world-wide rivers. This research indicates the further study necessity of the Moscow region to cover more contaminated sites and environmental compartments.
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