title: Distribution patterns of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in sediments of the Xiangjiang River, China.
abstract: We investigated the occurrence and distribution patterns of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in six sediment samples from the Xiangjiang River, Hunan Province, People's Republic of China. Total concentrations of PCDD/Fs ranged from 876 to 497,759 (mean 160,766) ng/kg dw, the highest of which exceeded that have ever been reported for sediment samples. World Health Organization total toxicity equivalent (WHO-TEQ) concentrations in three out of six samples were significantly higher than the guidance level (21.5 ng WHO-TEQ/kg dw) suggested by Canadian Sediment Quality Guideline. A predominance of octachlorodibenzo-p-dioxin (OCDD) was observed with an average contribution of 90.8% to the total PCDD/F concentrations, while 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD) was the major contributor to the PCDD/F WHO-TEQ concentrations in most of the sites. Such high levels of OCDD and HpCDD may be attributed to the presence of PCP/PCP-Na pollution, although MB-WW, agricultural straw open burning, and boilers-hazardous wastes were also the potential sources of PCDD/Fs. This is the first report for the concentrations and congener profiles of PCDD/Fs in sediment samples from the Xiangtan, Zhuzhou, and Changsha sections of the Xiangjiang River, providing scientific evidence for establishing priorities to reduce ecological risks posed by PCDD/Fs in the rapidly developing areas of Hunan Province and elsewhere.
authors.affiliation: Ministry of Environmental Protection, South China Institute of Environmental Sciences, Guangzhou 510655, People's Republic of China.
authors.forename: Zhiliang
authors.initials: Z
authors.lastname: Chen
authors.forename: Bing
authors.initials: B
authors.lastname: Yang
authors.forename: Alessio
authors.initials: A
authors.lastname: Mengoni
authors.forename: Jiahua
authors.initials: J
authors.lastname: Dong
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Peng
mesh_terms: D001572:Benzofurans / Q000032:analysis*; D002681:China; D000072338:Dibenzofurans, Polychlorinated; D004147:Dioxins / Q000032:analysis*; D052244:Endocrine Disruptors / Q000032:analysis; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D045483:Rivers / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data
chemical_list: D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D004147:Dioxins; D052244:Endocrine Disruptors; D014874:Water Pollutants, Chemical; C020887:dibenzo(1,4)dioxin