title: Toxic effects of crude-oil-contaminated soil in aquatic environment on Carassius auratus and their hepatic antioxidant defense system.
abstract: Under the indoor simulant conditions, toxic effects of crude-oil-contaminated soil which was put into aquatic environment on the young fishes Carassius auratus and their hepatic antioxidant system after a 20-d exposure were investigated. Results showed that the relationship between the mortality of C. auratus and the exposed doses could be divided into 3 phases: fishes exposed to the low dose groups (0.5-5.0 g/L) were dead due to the ingestion of crude-oil-contaminated soils in aquatic environment; at the medium dose groups (5.0-25.0 g/L) fishes were dead due to the penetration of toxic substances; at the high dose groups (25.0-50.0 g/L) fishes were dead due to environmental stress. The highest mortality and death speed were found in the 1.0 g/L dose group, and the death speed was sharply increased in the 50.0 g/L dose group in the late phase of exposure. The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and the content of malaondialdehyde (MDA) in the hepatic tissues of C. auratus were induced significantly. The activity of SOD was increased and then decreased. It was significantly inhibited in the 50.0 g/L dose group. The activity of CAT was highly induced, and restored to a level which is little more than the control when the exposed doses exceeded 10.0 g/L. The activity of GST was the most sensitive, it was significantly induced in all dose groups, and the highest elevation was up to 6 times in the 0.5 g/L dose group comparing with the control. The MDA content was significantly elevated in the 50.0 g/L dose group, and the changes of the MDA content were opposite with the changes of GST activity.
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria, Ministry of Education of China, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China. wangyy@mail.nankai.edu.cn
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Wang
authors.forename: Qixing
authors.initials: Q
authors.lastname: Zhou
authors.forename: Shengwei
authors.initials: S
authors.lastname: Peng
authors.forename: Lena Q
authors.initials: LQ
authors.lastname: Ma
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Niu
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D006054:Goldfish; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D010578:Petroleum / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D000975:Antioxidants; D010578:Petroleum; D014874:Water Pollutants, Chemical