The Science of the total environment
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Sci. Total Environ. · Oct 2010
Levels and patterns of Persistent Organic Pollutants (POPS) in selected food items from Northwest Russia (1998-2002) and implications for dietary exposure.
Residues of persistent organic pollutants (POPs) were analysed in 70 selected food items from Northwest Russia in 1998-2002. Levels of PCBs ranged from 0.2 to 16ng/g wet weight (ww) in dairy products and fats, 0.2 to 23ng/g ww in meat products, 0.5 to 16ng/g ww in eggs and 0.3 to 30ng/g ww in fish. High levels of DDT (16ng/g ww) were found in locally produced butter from Kola Peninsula, in pork fat from Arkhangels region (10 to 130ng/g ww) and in some fish samples from White Sea and Kargopol region (17 and 30ng/g ww). ⋯ Consumption of meat and poultry were important sources for intake of DDTs and HCHs, respectively. Contamination of animal feed and agricultural practice were assumed the most important causes for the results in the present study. However, increased control on maximum residue levels in food and feed may have resulted in large changes on levels and patterns of POPs in food in the studied areas.
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Sci. Total Environ. · Sep 2010
The relationship between particulate air pollution and emergency hospital visits for hypertension in Beijing, China.
A number of epidemiological studies have examined the adverse effect of air pollution on mortality and morbidity. Also, several studies have investigated the associations between air pollution and specific-cause diseases including arrhythmia, myocardial infarction, and heart failure. However, little is known about the relationship between air pollution and the onset of hypertension. ⋯ Elevated levels of ambient particulate matters are associated with an increase in EHVs for hypertension in Beijing, China.
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Sci. Total Environ. · Oct 2009
2020s scenario analysis of nutrient load in the Mekong River Basin using a distributed hydrological model.
A distributed hydrological model, YHyM, was integrated with the export coefficient concept and applied to simulate the nutrient load in the Mekong River Basin. In the validation period (1992-1999), Nash-Sutcliffe efficiency was 76.4% for discharge, 65.9% for total nitrogen, and 45.3% for total phosphorus at Khong Chiam. ⋯ Overall, the noticeable nutrient sources are cropland in the middle region and urban load in the lower region. The installation of waste water treatment plants in urban areas possibly cut 60.6%N and 19.9%P of the estimated increase in the case without any treatment.
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Sci. Total Environ. · Sep 2009
Skin penetrating abilities and reservoir effects of neat DMF and DMF/water mixtures.
This study was set out to determine the skin permeabilities of neat N, N-dimethylformamide (DMF, denoted as DMF(100%)) and DMF/water mixtures (including 50% DMF/50% water and 10% DMF/90% water mixtures (v/v), denoted as DMF(50%) and DMF(10%), respectively) and to assess their skin reservoir effects on the systemic absorption. The penetration fluxes for DMF(10%) and DMF(50%) (=0.015 and 0.126 mg/cm(2)/h, respectively) were only approximately 1.1%and 15% in magnitude as that of DMF(100%) (=0.872+/-0.231 mg/cm(2)/h), respectively. The above results could be because the perturbation effect of the DMF content was much more significant than the rehydration effect of the water content on skin permeability. ⋯ We found that the half-life (T(1/2)) of DMF retaining in the skin layer were 12.3, 4.07 and 1.24h for DMF(100%), DMF(50%) and DMF(10%), respectively. The estimated reservoir effect for DMF(100%) (=34.1%) was higher than that of DMF(50%) and DMF(10%) (=27.1% and 14.1%, respectively). The above results suggest that the impact associated with the internal burden of DMF could be prolonged even the external exposure of DMF is terminated, particularly for those dermal contact with DMF/water mixtures with high DMF contents.