[Measurement and preliminary human health risk assessment of representative organochlorines in farmed Mandarin fish].

Concentrations of representative organochlorines (OCs), including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in a batch of farmed mandarin fish from a cultivation pond in Wujiang City, Jiangsu Province, were determined with GC-ECD. Meanwhile, a preliminary human health risk assessment was conducted. Results showed that, the concentrations of dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and PCBs in the farmed mandarin fish were in the range of 1.3-4.57 ng/g, 0.13-1.24 ng/g, 0.07-0.44 ng/g and 0-5.22 ng/g, respectively, with an average value of 2.96, 0.40, 1.27 and 0.7 ng/g, respectively. These values were far below the corresponding residue limits set by China's Ministry of Health and the U.S. Food and Drug Administration, and at the low end of the global pollution bar. Referring to the reference values given by USEPA Integrated Risk Information System, calculated non-carcinogenic hazard ratios (HRs) of DDTs, HCB and PCBs were all <1 and carcinogenic HRs of DDTs, HCHs, HCB and PCBs were all >1. The results indicated that DDTs, HCHs and HCB in farmed mandarin fish did not have negative human health influence, but existed potential carcinogenic risk to humans. Compared to rural residents, urban residents were more vulnerable to DDTs, HCHs, HCB and PCBs threats.

Four trace elements contents of water environment of mining subsidence in the Huainan diggings, China.

Mining subsidence pool is the special waters formed by coal mining, located near the mine. We understand the impact on these waters of the surrounding coal production activities and the electricity plant through research the content and characteristics of harmful trace elements in coal contained in these waters. Pb, Hg, Se and Cr these four trace elements increase 0.52, 0.78, 0.70 and 0.28% respectively in Datong mining subsidence pool from November 2004 to November 2006; the four elements increase 1.52, 1.23, 1.08 and 1.08% respectively in Xie'er mining subsidence pool; the four elements increase 1.01, 1.06, 1.02 and 0.83% respectively in Pansan mining subsidence pool. The absolute value of Pb, Hg, Se and Cr in mining subsidence pool is related with their background value, while the increase in their concentration and their environment of mine and electricity plant surrounded are closely linked.