The concentration and distribution of three persistent organic pollutants （hexachlorocyclohexanes （HCHs）, dichlorodiphenyltrichloroethanes （DDTs） and polyehlorinated biphenyls （PCBs）） was assessed in tidal fia...The concentration and distribution of three persistent organic pollutants （hexachlorocyclohexanes （HCHs）, dichlorodiphenyltrichloroethanes （DDTs） and polyehlorinated biphenyls （PCBs）） was assessed in tidal fiat sediments collected from the south bank of Hangzhou Bay, China from 2009 to 2013. Gas chromatography coupled to triple quadrupole mass spectrometry （GC-MS/MS） was used for analysis, based on United States Environmental Protection Agency methods EPAS080A, EPA8081B, and EPA3550B. The results showed that the levels of HCHs, DDTs and PCBs decreased in the order of DDTs 〉 HCHs 〉 PCBs, and their mass fractions ranged from 0.29-32.91, 0.09-13.19 and 0.16-4.10 ktg/kg （dry mass）, respectively. The levels of HCHs, DDTs and PCBs decreased slowly from 2009 to 2013, with considerably greater concentrations in winter than in spring and summer. In this study area, the concentrations of DDTs and HCHs decreased gradually towards the mouth of Hangzhou Bay, while the concentrations of PCBs were related to changes in the local economy. In addition, the sources of HCHs and DDTs were identified as atmospheric precipitation and historical residues, Finally, we predicted that PCBs pollution primarily originated from Aroclor 1254（Lot A4）, which might root in the illegal demolition and stacking of abandoned paint, transformer or electronic equipment in the south bank of Hangzhou Bay.展开更多
基金Supported by the Medical and Health Science Research Foundation of Zhejiang Province(No.2011RCA031)the Agriculture and Social Development Funds of Ningbo,China(No.2012C0030)
文摘The concentration and distribution of three persistent organic pollutants （hexachlorocyclohexanes （HCHs）, dichlorodiphenyltrichloroethanes （DDTs） and polyehlorinated biphenyls （PCBs）） was assessed in tidal fiat sediments collected from the south bank of Hangzhou Bay, China from 2009 to 2013. Gas chromatography coupled to triple quadrupole mass spectrometry （GC-MS/MS） was used for analysis, based on United States Environmental Protection Agency methods EPAS080A, EPA8081B, and EPA3550B. The results showed that the levels of HCHs, DDTs and PCBs decreased in the order of DDTs 〉 HCHs 〉 PCBs, and their mass fractions ranged from 0.29-32.91, 0.09-13.19 and 0.16-4.10 ktg/kg （dry mass）, respectively. The levels of HCHs, DDTs and PCBs decreased slowly from 2009 to 2013, with considerably greater concentrations in winter than in spring and summer. In this study area, the concentrations of DDTs and HCHs decreased gradually towards the mouth of Hangzhou Bay, while the concentrations of PCBs were related to changes in the local economy. In addition, the sources of HCHs and DDTs were identified as atmospheric precipitation and historical residues, Finally, we predicted that PCBs pollution primarily originated from Aroclor 1254（Lot A4）, which might root in the illegal demolition and stacking of abandoned paint, transformer or electronic equipment in the south bank of Hangzhou Bay.
