| الوصف: |
Food consumption is an important pathway of human exposure to persistent organic pollutants (POPs). Market basket surveys for POPs have been conducted worldwide; however, there are very few surveys that cover all the major POPs for a comprehensive assessment of overall exposure. The primary objective of this study is to monitor a broad spectrum of POPs present in seafood samples collected from two coastal cities in China, with a view to evaluate the potential cancer and noncancer risks on humans exposed to these contaminants due to food consumption. Seafood is a major dietary component for coastal populations in China. According to a questionnaire-based dietary survey conducted in a Chinese coastal city, Zhoushan, in 2001, daily consumption of fishes, crabs, cephalopods, shrimps and bivalves were 105 g, 17.3 g, 3.37 g, 54.1 g, and 76.5 g wet wt., respectively, for an adult. In the first instance, fish samples were selected as the study targets because fish constitute an important dietary component in Chinese coastal cities. The concentrations of organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs) ranged from 0.67 to 13 and 0.24 to 1.4 ng/g wet wt., respectively. The hazard ratios (HRs), based on non-cancer endpoints, were all less than unity, while the cancer-based HRs were greater than unity for certain contaminants based on the 95th centile concentration in fish tissue. Results of this preliminary study indicated that fish consumption may pose a lifetime cancer risk of greater than one in one million, and thus further studies were conducted to cover a wider range of contaminants in a more extensive selection of seafood samples. In the second study, comprehensive market basket surveys were undertaken at two coastal cities, Guangzhou and Zhoushan. In this study, polychlorinated compounds, including PCBs, non- and mono-ortho-PCBs, polychlorinated naphthalenes (PCNs) and polychlorinated dibenzo-p-dioxins and furans (PCDDs/DFs); polybrominated compounds, including polybrominated diphenyl ethers ... |
