title: Ecotoxicological bioassays of sediment leachates in a river bed flanked by decommissioned pesticide plants in Nantong City, East China.
abstract: Traditionally, the toxicity of river contaminants is analyzed chemically or physically through river bed sediments. The biotoxicity of polluted sediment leachates has not caught our attention. This study aims to overcome this deficiency through a battery of biotests which were conducted to monitor comprehensive toxicity of sediment leachates for the Yaogang River in East Jiangsu Province of China, which is in close proximity to former pesticide plants. The general physical and chemical parameters of major pollutants were analyzed from river bed sediments collected at five strategic locations. The ecotoxicity analyses undertaken include overall fish (adult zebrafish) acute toxicity, luminescent bacteria (Vibrio fischeri) bioassay, and zebrafish embryo toxicity assay. Compared with the control group, sediment leachates increased the lethality, inhibited the embryos hatching and induced development abnormalities of zebrafish embryos, and inhibited the luminescence of V. fischeri. The results show that sediment leachates may assume various toxic effects, depending on the test organism. This diverse toxicity to aquatic organisms reflects their different sensitivity to sediment leachates. It is found clearly that V. fischeri was the organism which was characterized by the highest sensitivity to the sediment leachates. The complicated toxicity of leachates was not caused by one single factor but by multiple pollutants together. This indicates the need of estimations of sediment leachate not only taking into account chemical detection but also of applying the biotests to the problem. Thus, multigroup bioassays are necessary to realistically evaluate river ecological risks imposed by leachates.
authors.affiliation: State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Science, Ministry of Environmental Protection of China (MEPC), Nanjing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: School of Environment, Nanjing Normal University, Nanjing, China.
authors.forename: Fenghe
authors.initials: F
authors.lastname: Wang
authors.affiliation: State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Science, Ministry of Environmental Protection of China (MEPC), Nanjing, China. wjz@nies.org.
authors.forename: Jinzhong
authors.initials: J
authors.lastname: Wan
authors.affiliation: State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Science, Ministry of Environmental Protection of China (MEPC), Nanjing, China.
authors.forename: Jian
authors.initials: J
authors.lastname: He
authors.affiliation: State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Science, Ministry of Environmental Protection of China (MEPC), Nanjing, China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Li
authors.affiliation: State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Science, Ministry of Environmental Protection of China (MEPC), Nanjing, China.
authors.lastname: Qiang Chen
authors.affiliation: School of Environment, The University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors.forename: Jay
authors.initials: J
authors.lastname: Gao
authors.affiliation: State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Science, Ministry of Environmental Protection of China (MEPC), Nanjing, China.
authors.forename: Yusuo
authors.initials: Y
authors.lastname: Lin
authors.affiliation: State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control, Nanjing Institute of Environmental Science, Ministry of Environmental Protection of China (MEPC), Nanjing, China. zst@nies.org.
authors.forename: Shengtian
authors.initials: S
authors.lastname: Zhang
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects; D000818:Animals; D001681:Biological Assay; D002681:China; D019015:Geologic Sediments / Q000737:chemistry; D010575:Pesticides; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical
chemical_list: D010575:Pesticides; D014874:Water Pollutants, Chemical
keywords: Bioassays; Ecotoxicology; Pesticide; Sediment leachates; Zebrafish