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Influence of open vegetation fires on black carbon and ozone variability in the southern Himalayas (NCO-P, 5079 m a.s.l.) 全文
2014
Putero, D. | Landi, T.C. | Cristofanelli, P. | Marinoni, A. | Laj, P. | Duchi, R. | Calzolari, F. | Verza, G.P. | Bonasoni, P.
We analysed the variability of equivalent black carbon (BC) and ozone (O3) at the global WMO/GAW station Nepal Climate Observatory-Pyramid (NCO-P, 5079 m a.s.l.) in the southern Himalayas, for evaluating the possible contribution of open vegetation fires to the variability of these short-lived climate forcers/pollutants (SLCF/SLCP) in the Himalayan region.We found that 162 days (9% of the data-set) were characterised by acute pollution events with enhanced BC and O3 in respect to the climatological values. By using satellite observations (MODIS fire products and the USGS Land Use Cover Characterization) and air mass back-trajectories, we deduced that 56% of these events were likely to be affected by emissions from open fires along the Himalayas foothills, the Indian Subcontinent and the Northern Indo-Gangetic Plain.These results suggest that open fire emissions are likely to play an important role in modulating seasonal and inter-annual BC and O3 variability over south Himalayas.
显示更多 [+] 显示较少 [-]Modelling uptake and toxicity of nickel in solution to Enchytraeus crypticus with biotic ligand model theory 全文
2014
He, Erkai | Qiu, Hao | Van Gestel, Cornelis A.M.
Protons and other cations may inhibit metal uptake and alleviate metal toxicity in aquatic organisms, but less is known about these interactions in soil organisms. The present study investigated the influence of solution chemistry on uptake and toxicity of Ni in Enchytraeus crypticus after 14 days exposure. Ca2+, Mg2+ and Na+ were found to exert significant effects on both uptake and toxicity of Ni. An extended Langmuir model, which incorporated cation competition effects, well predicted Ni uptake. The LC50{Ni2+} predicted by a developed Biotic Ligand Model matched well with observed values. These suggest that cation competition needs to be taken into account when modelling uptake and effects. The binding constants of Ni2+, Mg2+ and Na+ on the uptake and toxic action sites were similar, but for Ca2+ they differed. This indicates that the effect of Ca2+ on Ni2+ toxicity cannot simply be explained by the competition for entry into organism.
显示更多 [+] 显示较少 [-]Arsenic speciation in total contents and bioaccessible fractions in atmospheric particles related to human intakes 全文
2014
Huang, Minjuan | Chen, Xunwen | Zhao, Yinge | Yu Chan, Chuen | Wang, Wei | Wang, Xuemei | Wong, Ming Hung
Speciation of inorganic trivalent arsenicals (iAsIII), inorganic pentavalent arsenicals (iAsV), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) in total arsenic (As) content and its bioaccessible fractions contained in road dust, household air-conditioning (AC) filter dust and PM2.5 was investigated. Inorganic As, especially iAsV, was observed as the dominant species. Physiologically based extraction test (PBET), an in-vitro gastrointestinal method, was used to estimate the oral As bioaccessibility in coarse particles and the species present in the oral bioaccessible fraction. A composite lung simulating serum was used to mimic the pulmonary condition to extract the respiratory bioaccessible As and its species in PM2.5. Reduction of iAsV to iAsIII occurred in both in-vitro gastrointestinal and lung simulating extraction models. The inorganic As species was the exclusive species for absorption through ingestion and inhalation of atmospheric particles, which was an important exposure route to inorganic As, in addition to drinking water and food consumption.
显示更多 [+] 显示较少 [-]Determining the bioavailability and toxicity of lead contamination to earthworms requires using a combination of physicochemical and biological methods 全文
2014
Luo, Wei | Verweij, Rudo A. | van Gestel, Cornelis A.M.
This study aimed at assessing the bioavailability and toxicity of lead to Eisenia andrei in shooting range soils representing different land uses (forest, grassland, bullet plot). Soils contained 47–2398 mg Pb/kg dry weight (dw), but also had different pH-CaCl2 (3.2–6.8) and organic matter contents (3.8–13%). Therefore artificial soils with different pH and organic matter contents and two natural soils were included as control soils. Earthworms were exposed for 28 days and toxicity and uptake of Pb were related to total, water and 0.01 M CaCl2 extractable and porewater Pb concentrations as well as to soil characteristics. Pb uptake in the earthworms linearly increased with increasing soil concentrations. At >2000 mg Pb/kg dw and pH 3.3–3.5, high earthworm mortality with significant weight loss and complete inhibition of reproduction were recorded. At <1000 mg/kg dw, earthworm reproduction was more related to differences in pH and other soil characteristics than to Pb.
显示更多 [+] 显示较少 [-]Pharmaceuticals occurrence in a WWTP with significant industrial contribution and its input into the river system 全文
2014
Collado, N. | Rodriguez-Mozaz, S. | Gros, M. | Rubirola, A. | Barceló, D. | Comas, J. | Rodriguez-Roda, I. | Buttiglieri, G.
Occurrence and removal of 81 representative Pharmaceutical Active Compounds (PhACs) were assessed in a municipal WWTP located in a highly industrialized area, with partial water reuse after UV tertiary treatment and discharge to a Mediterranean river. Water monitoring was performed in an integrated way at different points in the WWTP and river along three seasons.Consistent differences between therapeutic classes were observed in terms of influent concentration, removal efficiencies and seasonal variation. Conventional (primary and secondary) treatment was unable to completely remove numerous compounds and UV-based tertiary treatment played a complementary role for some of them. Industrial activity influence was highlighted in terms of PhACs presence and seasonal distribution.Even if global WWTP effluent impact on the studied river appeared to be minor, PhACs resulted widespread pollutants in river waters. Contamination can be particularly critical in summer in water scarcity areas, when water flow decreases considerably.
显示更多 [+] 显示较少 [-]Toxicokinetics of metals in the earthworm Lumbricus rubellus exposed to natural polluted soils – relevance of laboratory tests to the field situation 全文
2014
Giska, Iwona | van Gestel, Cornelis A.M. | Skip, Borys | Laskowski, Ryszard
The aim of this study was to estimate the bioavailability of essential (Zn, Cu) and non-essential metals (Cd, Pb) to the earthworm Lumbricus rubellus exposed to soils originating from a gradient of metal pollution in Southern Poland. Metal uptake and elimination kinetics were determined and related to soils properties. Experimental results were compared with tissue metal concentrations observed in earthworms from the studied transect. Cd and Pb were intensively accumulated by the earthworms, with very slow or no elimination. Their uptake rate constants, based on 0.01 M CaCl2-extractable concentrations in the soils, increased with soil pH. Internal concentrations of Cu and Zn were maintained by the earthworms at a stable level, suggesting efficient regulation of these metals by the animals. The estimated uptake and elimination kinetics parameters enabled fairly accurate prediction of metal concentrations reached within a life span of L. rubellus in nature.
显示更多 [+] 显示较少 [-]Ecological responses to contamination: A meta-analysis of experimental marine studies 全文
2014
O'Brien, Allyson L. | Keough, Michael J.
Identifying general response patterns to contamination in the environment is critical for reliable assessments of ecosystem health. However, it is not often clear if there are biases in the information used to understand general effects of contamination. To investigate this we conducted a review of 314 studies that experimentally manipulated contaminants and measured the effects on marine invertebrate taxa. The majority of studies investigated the effects of metals (54%) on individual taxa (mainly bivalves, amphipods, copepods). Ecologically relevant responses to contamination were measured in only 22% of the studies. A meta-analysis using studies that measured ecological responses to copper illustrated a general negative effect of copper and highlighted the bias towards field or laboratory experiments that measure community or individual-level responses. There is a need for diversification of studies that investigate the ecological effects of contamination as an important advancement in ecotoxicology and ecological research and environmentally relevant risk assessments.
显示更多 [+] 显示较少 [-]Comparing sediment equilibrium partitioning and passive sampling techniques to estimate benthic biota PCDD/F concentrations in Newark Bay, New Jersey (U.S.A.) 全文
2014
Friedman, Carey L. | Lohmann, Rainer
Sediment and polyethylene sampler-based estimates of polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/F) concentrations in Newark Bay, New Jersey (USA) benthic biota were compared. Biota concentrations based on sediment were estimated using an organic carbon (OC)-water partitioning model and an OC and black carbon (BC)-water dual model. Biota concentrations based on polyethylene were estimated from samplers deployed in the Newark Bay water column and samplers immersed in a sediment/porewater slurry in the laboratory. Porewater samplers provided the best estimates of biota concentrations (within 3.1×), with best results achieved for deposit-feeders (within 1.6×). Polyethylene deployed in deep water also provided good estimates of biota concentrations (within 4×). By contrast, OC-water partitioning overestimated biota concentrations by up to 7×, while OC and BC combined underestimated biota concentrations by up to 13×. We recommend passive samplers such as polyethylene for estimating concentrations of hydrophobic organic contaminants in field biota given its simplicity and relatively lower uncertainty compared to sediment equilibrium partitioning.
显示更多 [+] 显示较少 [-]Evidence of altered fertility in female roach (Rutilus rutilus) from the River Seine (France) 全文
2014
Gerbron, M. | Geraudie, P. | Fernandes, D. | Rotchell, J.M. | Porte, C. | Minier, C.
A large variety of anthropogenic chemicals present in the aquatic environment have been shown to be able to alter the endocrine system of exposed organisms, potentially impacting their reproductive function. The aim of this study was to assess the effects of environmental pollution on the reproductive system of wild female roach (Rutilus rutilus) from the Seine River (Normandy, France). A suite of biomarkers of endocrine disruption including gonado-somatic index, plasmatic vitellogenin, gonadal aromatase activity and histological parameters (oocyte diameter and gonad maturation) were studied. Female fish from the polluted sites showed a number of reproductive alterations, including inhibited gonad maturation, reduced oocyte growth, reduced levels of plasmatic vitellogenin and 3-fold lower gonadal aromatase activity than females collected in the reference site. Overall, these results highlight the presence of endocrine disruption in female roach from the Seine River.
显示更多 [+] 显示较少 [-]Air pollution and hospital admissions for respiratory diseases in Lanzhou, China 全文
2014
Tao, Yan | Mi, Shengquan | Zhou, Shuhong | Wang, Shigong | Xie, Xiaoyun
Lanzhou is among the most seriously air-polluted cities in China as a whole, due to its unique topography, climate, industrial structure and so on. We studied the relationship between different air pollution and respiratory hospitalizations from 2001 to 2005, the total of respiratory hospital admissions were 28,057. The data were analyzed using Poisson regression models after controlling for the long time trend for air pollutants, the “day of week” effect and confounding meteorological factors. Three air pollutants (PM10, SO2, NO2) had a lag effect, the lag was 3–5 days for PM10, 1–3 days for SO2 and 1–4 days for NO2. The relative risks were calculated for increases in the inter-quartile range of the pollutants (139 μg/m3 in PM10, 61 μg/m3 in SO2 and 31 μg/m3 in NO2). Results showed that there were significant associations between air pollutants and respiratory hospital admissions, and stronger effects were observed for females and aged ≥65 yrs in Lanzhou.
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