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China's water pollution by persistent organic pollutants
2012
Bao, Lian-Jun | Maruya, Keith A. | Snyder, Shane A. | Zeng, E. Y. (Eddy Y.)
Available data were reviewed to assess the status of contamination by persistent organic pollutants (POPs), including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), in drinking water sources and coastal waters of China. The levels of POPs in China's waters were generally at the high end of the global range. A comparison of China's regulatory limits indicated that PCBs in rivers and coastal water may pose potential human health risk. Occurrence of DDTs in some rivers of China may also pose health risk to humans using the regulatory limits of DDTs recommended by the European Union. Future monitoring of POPs in China's waters should be directed towards analytes of concern (e.g. PCBs and PCDD/Fs) and to fill data gaps for analytes (e.g. PBDEs, PCDD/Fs, and chlordane) and in watersheds/regions (e.g. West China) where data are scarce.
Show more [+] Less [-]The interaction rainfall vs. weight as determinant of total mercury concentration in fish from a tropical estuary
2012
Barletta, M. | Lucena, L.R.R. | Costa, M.F. | Barbosa-Cintra, S.C.T. | Cysneiros, F.J.A.
Mercury loads in tropical estuaries are largely controlled by the rainfall regime that may cause biodilution due to increased amounts of organic matter (both live and non-living) in the system. Top predators, as Trichiurus lepturus, reflect the changing mercury bioavailability situations in their muscle tissues. In this work two variables [fish weight (g) and monthly total rainfall (mm)] are presented as being important predictors of total mercury concentration (T-Hg) in fish muscle. These important explanatory variables were identified by a Weibull Regression model, which best fit the dataset. A predictive model using readily available variables as rainfall is important, and can be applied for human and ecological health assessments and decisions. The main contribution will be to further protect vulnerable groups as pregnant women and children. Nature conservation directives could also improve by considering monitoring sample designs that include this hypothesis, helping to establish complete and detailed mercury contamination scenarios.
Show more [+] Less [-]Warm season chloride concentrations in stream habitats of freshwater mussel species at risk
2012
Todd, Aaron K. | Kaltenecker, M Georgina
Warm season (May–October) chloride concentrations were assessed in stream habitats of freshwater mussel species at risk in southern Ontario, Canada. Significant increases in concentrations were observed at 96% of 24 long-term (1975–2009) monitoring sites. Concentrations were described as a function of road density indicating an anthropogenic source of chloride. Linear regression showed that 36% of the variation of concentrations was explained by road salt use by the provincial transportation ministry. Results suggest that long-term road salt use and retention is contributing to a gradual increase in baseline chloride concentrations in at risk mussel habitats. Exposure of sensitive mussel larvae (glochidia) to increasing chloride concentrations may affect recruitment to at risk mussel populations.
Show more [+] Less [-]Monitoring of selected estrogenic compounds and estrogenic activity in surface water and sediment of the Yellow River in China using combined chemical and biological tools
2012
Wang, Li | Ying, Guang-Guo | Chen, Feng | Zhang, Li-Juan | Zhao, Jian-Liang | Lai, Hua-Jie | Chen, Zhi-Feng | Tao, Ran
We investigated occurrence of selected compounds (4-t-octylphenol: 4-t-OP; 4-nonylphenols: 4-NP; bisphenol-A: BPA; estrone: E1; 17β-estradiol: E2; triclosan: TCS) and estrogenicity in surface water and sediment of the Yellow River in China by using combined chemical analysis and in vitro yeast screen bioassay. Estrogenic compounds 4-t-OP, 4-NP, BPA, E1, E2 and TCS were measured in the water samples, with their average concentrations of 4.7, 577.9, 46.7, 1.3, ND and 6.8 ng/L, respectively. In sediment, the average concentrations of 4-t-OP, 4-NP, BPA and TCS were 35.7, 0.5, 1.7 and 0.7 ng/g while E1 and E2 were not detected in the sediments of all selected sites. In general, the estrogenic compounds in surface water and sediment of the Yellow River were at relatively low levels, thus having medium to minimal estrogenic risks in most sites except for the site of east Lanzhou with high estrogenic risks.
Show more [+] Less [-]Spatial patterns and temporal trends in mercury concentrations, precipitation depths, and mercury wet deposition in the North American Great Lakes region, 2002–2008
2012
Risch, Martin R. | Gay, David A. | Fowler, Kathleen K. | Keeler, Gerard J. | Backus, Sean M. | Blanchard, Pierrette | Barres, James A. | Dvonch, J Timothy
Annual and weekly mercury (Hg) concentrations, precipitation depths, and Hg wet deposition in the Great Lakes region were analyzed by using data from 5 monitoring networks in the USA and Canada for a 2002–2008 study period. High-resolution maps of calculated annual data, 7-year mean data, and net interannual change for the study period were prepared to assess spatial patterns. Areas with 7-year mean annual Hg concentrations higher than the 12 ng per liter water-quality criterion were mapped in 4 states. Temporal trends in measured weekly data were determined statistically. Monitoring sites with significant 7-year trends in weekly Hg wet deposition were spatially separated and were not sites with trends in weekly Hg concentration. During 2002–2008, Hg wet deposition was found to be unchanged in the Great Lakes region and its subregions. Any small decreases in Hg concentration apparently were offset by increases in precipitation.
Show more [+] Less [-]Distributions and impact factors of antimony in topsoils and moss in Ny-Ålesund, Arctic
2012
Jia, Nan | Sun, Liguang | He, Xin | You, Kehua | Zhou, Xin | Long, Nanye
The distribution of antimony (Sb) in topsoil and moss (Dicranum angustum) in disturbed and undisturbed areas, as well as coal and gangue, in Ny-Ålesund, Arctic was examined. Results show that the weathering of coal bed could not contribute to the increase of Sb concentrations in topsoil and moss in the study area. The distribution of Sb is partially associated with traffic and historical mining activities. The occurrence of the maximum Sb concentration is due to the contribution of human activities. In addition, the decrease of Sb content in topsoil near the coastline may be caused by the washing of seawater. Compared with topsoils, moss could be a useful tool for monitoring Sb in both highly and lightly polluted areas.
Show more [+] Less [-]A multimedia fate model to evaluate the fate of PAHs in Songhua River, China
2012
Wang, Ce | Feng, Yujie | Sun, Qingfang | Zhao, Shanshan | Gao, Peng | Li, Bai-Lian
A multimedia fate model coupling dynamic water flow with a level IV fugacity model has been developed and applied to simulate the temporal and spatial fate of Polycyclic Aromatic Hydrocarbons (PAHs) in the Songhua River, China. The model has two components: in the first, the one-dimensional network kinematic wave equation is used to calculate varying water flow and depth. In the second, Fugacity IV equations are implemented to predict contaminant distributions in four environmental media. The estimated concentrations of eight PAHs in Songhua River are obtained, and all simulated results are in acceptable agreement with monitoring data, as verified with the Theil’s inequality coefficient test. The sensitivity of PAH concentration in each environmental phase to input parameters are also evaluated. Our results show the model predicts reasonably accurate contaminant concentrations in natural rivers, and that it can be used to supply necessary information for control and management of water pollution.
Show more [+] Less [-]Quantifying the impacts of socio-economic factors on air quality in Chinese cities from 2000 to 2009
2012
Zhao, Juanjuan | Chen, Shengbin | Wang, Hua | Ren, Yin | Du, Ke | Xu, Weihua | Zheng, Hua | Jiang, Bo
Socio-economic factors have significant influences on air quality and are commonly used to guide environmental planning and management. Based on data from 85 long-term daily monitoring cities in China, air quality as evaluated by AOFDAQ-A (Annual Occurrence Frequency of Daily Air Quality above Level III), was correlated to socio-economic variable groups of urbanization, pollution and environmental treatment by variation partitioning and hierarchical partitioning methods. We found: (1) the three groups explained 43.5% of the variance in AOFDAQ-A; (2) the contribution of “environmental investment” to AOFDAQ-A shown a time lag effect; (3) “population in mining sector” and “coverage of green space in built-up area” were respectively the most significant negative and positive explanatory socio-economic variables; (4) using eight largest contributing individual factors, a linear model to predict variance in AOFDAQ-A was constructed. Results from our study provide a valuable reference for the management and control of air quality in Chinese cities.
Show more [+] Less [-]The challenge of choosing environmental indicators of anthropogenic impacts in estuaries
2012
Dafforn, Katherine A. | Simpson, Stuart L. | Kelaher, Brendan P. | Clark, Graeme F. | Komyakova, Valeriya | Wong, Chris K.C. | Johnston, Emma L.
Ecological assessments over large spatial scales require that anthropogenic impacts be distinguishable above natural variation, and that monitoring tools are implemented to maximise impact detection and minimise cost. For three heavily modified and four relatively ‘pristine’ estuaries (disturbance category), chemical indicators (metals and PAHs) of anthropogenic stress were measured in benthic sediments, suspended sediments and deployed oysters, together with other environmental variables. These were compared with infaunal and hard-substrate invertebrate communities. Univariate analyses were useful for comparing contaminant loads between different monitoring tools and identified the strongest relationships between benthic and suspended sediments. However, multivariate analyses were necessary to distinguish ecological response to anthropogenic stressors from environmental “noise” over a large spatial scale and to identify sites that were being impacted by contaminants. These analyses provide evidence that suspended sediments are a useful alternative monitoring tool to detect potential anthropogenic impacts on benthic (infaunal and hard-substrate) communities.
Show more [+] Less [-]Occupational exposure to airborne particles and other pollutants in an aviation base
2012
Buonanno, Giorgio | Bernabei, Manuele | Avino, Pasquale | Stabile, Luca
The occupational exposure to airborne particles and other pollutants in a high performance jet engine airport was investigated. Three spatial scales were considered: i) a downwind receptor site, ii) close to the airstrip, iii) personal monitoring. Particle number, surface area, mass concentrations and distributions were measured as well as inorganic and organic fractions, ionic fractions and Polycyclic Aromatic Hydrocarbons. Particle number distribution measured at a receptor site presents a mode of 80 nm and an average total concentration of 6.5 × 10³ part. cm⁻³; the chemical analysis shows that all the elements may be attributed to long-range transport from the sea. Particle number concentrations in the proximity of the airstrip show short term peaks during the working day mainly related to takeoff, landing and pre-flight operations of jet engines. Personal exposure of workers highlights a median number concentration of 2.5 × 10⁴ part. cm⁻³ and 1.7 × 10⁴ part. cm⁻³ for crew chief and hangar operator.
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