title: Polychlorinated biphenyl congeners and organochlorine insecticides in the water column and sediments of Daya Bay, China.
abstract: Samples of sub-surface water, suspended particulate matter (SPM) and surface sediments collected from Daya Bay, China have been analysed for 12 polychlorinated biphenyl (PCB) congeners and 18 organochlorine insecticides, using gas chromatography electron capture detection. Total PCB levels varied from 91.1 to 1355.3 ng l-1 in water and from 0.85 to 27.37 ng g-1 dry weight in sediments. The levels of total organochlorine insecticides were in the range 143.3-5104.8 ng l-1 in water and 2.43-86.25 ng g-1 dry weight in sediment. None of the target compounds were detected in SPM. The levels of total hexachlorocyclohexanes in water varied from 35.5 to 1228.6 ng l-1, whilst in sediments they ranged from 0.32 to 4.16 ng g-1 dry weight. For the sum of dichlorodiphenyltrichloroethanes (DDTs), their levels were in the range 26.8-975.9 ng l-1 in water, and 0.14-20.27 ng g-1 dry weight in sediments. The distribution profiles of these contaminants in water and sediments suggest that there are a number of sources contributing to total contaminant burden in the bay, including soil runoffs, wastewater discharges, sewage outfalls and shipping activites. Ratios of DDT/(DDE + DDD) in the water and sediments indicate recent inputs of such chemicals into the day. The results, therefore, provide important information on the current contamination status of a key aquacultural area in China, and point to the need for urgent actions to stop the use of persistent agrochemicals such as DDT and lindane.
authors: Centre for Environmental Research, School of Chemistry, Physics and Environmental Science, University of Sussex, Falmer, Brighton BN1 9QJ, UK. j.zhou@sussex.ac.uk
authors: J L
authors: JL
authors: Zhou
authors: K
authors: K
authors: Maskaoui
authors: Y W
authors: YW
authors: Qiu
authors: H S
authors: HS
authors: Hong
authors: Z D
authors: ZD
authors: Wang
mesh_terms: D017756:Aquaculture; D002849:Chromatography, Gas; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D007306:Insecticides / Q000032:analysis*; D010316:Particle Size; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D007306:Insecticides; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls