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The levels and distributions of polybrominated diphenyl ethers (PBDEs) in chicken tissues from an electronic waste (e-waste) recycling area in southeast China were investigated. Human dietary intake by local residents via chicken muscle and eggs was estimated. The mean PBDEs concentrations in tissues ranged from 15.2 to 3138.1 ng/g lipid weight (lw) and in egg the concentration was 563.5 ng/g lw. The results showed that the level of total PBDEs (PPBDEs) in the chicken tissue was 2–3 orders of magnitude higher than those reported in the literature. The large di erence of PPBDEs concentrations between tissues confirmed that the distribution of PBDEs in tissues depend on tissue-specificity rather than the “lipid-compartment”. BDE-209 was the predominant congener (82.5%– 94.7% of PPBDEs) in all chicken tissues except in brain (34.7% of PPBDEs), which indicated that deca-BDE (the major commercial PBDE formulation comprising 65%–70% of total production) was major pollution source in this area and could be bioaccumulated in terrestrial animals. The dietary PBDEs intake of the local residents from chicken muscle and egg, assuming only local bred chickens and eggs were consumed, ranged from 2.2 to 22.5 ng/(day kg body weight (bw)) with a mean value of 13.5 ng/(day kg bw), which was one order of magnitude higher than the value reported in previous studies for consumption of all foodstu s.  相似文献
2.
The characteristics of ammonia in drinking water sources in China were evaluated during 2005-2009. The spatial distribution and seasonal changes of ammonia in different types of drinking water sources of 22 provinces, 5 autonomous regions and 4 municipalities were investigated. The levels of ammonia in drinking water sources follow the order of river > lake/reservoir > groundwater. The levels of ammonia concentration in river sources gradually decreased from 2005 to 2008, while no obvious change was observed in the lakes/reservoirs and groundwater drinking water sources. The proportion of the type of drinking water sources is different in different regions. In river drinking water sources, the ammonia level was varied in different regions and changed seasonally. The highest value and wide range of annual ammonia was found in South East region, while the lowest value was found in Southwest region. In lake/reservoir drinking water sources, the ammonia levels were not varied obviously in different regions. In underground drinking water sources, the ammonia levels were varied obviously in different regions due to the geological permeability and the natural features of regions. In the drinking water sources with higher ammonia levels, there are enterprises and wastewater drainages in the protected areas of the drinking water sources.  相似文献
3.
In this work, a method was developed and optimized for the analysis of polyfluoroalkyl and/or perfluoroalkyl substances (PFASs) content in surface water and sediment samples with high instrumental response and good separation. Surface water and sediment samples were collected from the Yangtze River Delta (YRD) to analyze the distribution characteristics of perfluoroalkyl carboxylic acids (PFCAs), perfluoroalkane sulfonic acids (PFSAs), perfluoroalkyl phosphonic acids (PFPAs), perfluoroalkyl phosphinic acids (PFPiAs), and polyfluoroalkyl phosphoric acid diesters (diPAPs). The results showed that the total concentrations of PFCAs and PFSAs in YRD varied from 31 to 902 ng/L. PFCAs (≥ 11 carbons) and PFSAs (≥ 10 carbons atoms) were not detected in any surface water samples. The mean concentrations of all PFCAs and PFSAs in surface water from the sampling areas decreased in the following order: Yangtze river (191 ng/L) ≈ Taihu lake (189 ng/L) > Huangpu river (122 ng/L) ≈ Qiantang river (120 ng/L) > Jiaxing urban river (100 ng/L). Strong significant (p < 0.05) correlations between the concentrations of many of the compounds were found in the sampling areas, suggesting a common source for these compounds. Only perfluorooctanoic acid (PFOA) was observed in all sediment samples, at concentrations varying from 0.02 to 1.35 ng/g. Finally, detection rates of two diPAPs were only 8% and 10%, respectively and the concentration of diPAPs was two to three times lower compared to PFCAs and PFSAs.  相似文献
4.
Decabromodiphenyl ether (decaBDE), as a flame retardant, is widely produced and used. To study the thyroid disruption by technical decaBDE at low concentrations, Xenopus laevis tadpoles were exposed to technical decaBDE mixture DE-83R (1–1000 ng/L) in water from stage 46/47 (free swimming larvae, system of Nieuwkoop and Faber) to stage 62. DE-83R at concentration of 1000 ng/L significantly delayed the time to metamorphosis (presented by forelimb emergence, FLE). Histological examination showed that DE- 83R at all tested concentrations caused histological alterations – multilayer follicular epithelial cell and markedly increased follicle size accompanied by partial colloid depletion and increase in the peripheral colloid vacuolation, in thyroid glands. All tested concentrations of DE-83R also induced a down-regulation of thyroid receptor mRNA expression. These results demonstrated that technical decaBDE disrupted the thyroid system in X. laevis tadpoles. Analysis of polybrominated diphenyl ethers (PBDEs) (sum of 39 congeners) in X. laevis indicated that mean concentrations of total PBDEs in X. laevis exposed to 1, 10, 100, 1000 ng/L were 11.0, 128.1, 412.1, 1400.2 ng/g wet weight, respectively. Considering that PBDEs burden of X. laevis tadpoles was close to PBDEs levels in amphibians as reported in previous studies, our study has raised new concerns for thyroid disruption in amphibians of technical decaBDE at environmentally relevant concentrations.  相似文献
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