水體中石油污染土壤對鯽魚及其肝臟抗氧化系統的毒性效應

王媛媛，周啟星

南開大學環境科學與工程學院 環境污染過程與基準教育部重點實驗室，天津市城市生態環境修復與污染防治重點實驗室，天津300071

水體中石油污染土壤對鯽魚及其肝臟抗氧化系統的毒性效應

王媛媛，周啟星*

南開大學環境科學與工程學院 環境污染過程與基準教育部重點實驗室，天津市城市生態環境修復與污染防治重點實驗室，天津300071

在室內模擬條件下，研究了水體中不同濃度石油污染土壤暴露20d對鯽魚（Carassius auratus）幼體死亡率和肝臟抗氧化系統的影響.結果表明，鯽魚死亡率隨其暴露濃度的變化明顯分為3個部分：低濃度（0.5～5.0g·L-1）攝食死亡，中等濃度（5.0～25.0g·L-1）吸收死亡，高濃度（25.0～50.0g·L-1）脅迫死亡.1.0g·L-1濃度組死亡率最高，死亡速率最快；50.0g·L-1濃度組在暴露后期死亡速率迅速升高.鯽魚肝臟中谷胱甘肽硫轉移酶（GST）、過氧化氫酶（CAT）和超氧化物歧化酶（SOD）的活性可被顯著誘導，具體表現為：在所設濃度范圍內，幼體鯽魚肝臟GST活性均受到顯著激活，0.5g·L-1濃度下，GST活性被最大程度誘導，達到對照組的606%；SOD活性先升高后降低，10.0g·L-1時酶活性最強，50.0g·L-1濃度下活性被顯著抑制；CAT活性于0.5g·L-1就被顯著誘導，2.5g·L-1濃度是對照組的4.86倍.可以認為，鯽魚肝臟SOD和CAT，尤其GST活性對水體中石油污染土壤較敏感，均可作為水生生態系統中石油污染存在的早期檢測指標.

鯽魚；石油污染土壤；生態毒性；抗氧化系統；水環境

Received 20 December 2009 accepted 31 January 2010

Abstract：Under the indoor stimulant conditions,the effect of exposure to oil polluted soil in aquatic environment for 20 days on the death rate of the larval Carassius auratus and its hepatic antioxidant system were studied.Results showed that the relationship between the death rate of Carassius auratus and the exposure dose could be divided to three parts:the death in low dose groups（0.5～5.0g·L-1）was contributed to ingestion of toxic substances;the death in medium dose groups（5.0～25.0g·L-1）was related to the permeation of toxic substances;and the death in high dose groups（25.0～50.0g·L-1）was dependent on environmental stress.The highest death rate and death velocity appeared in the 1.0g·L-1dose group,and the death velocity increased sharply in the 50.0g·L-1dose group in the late phase of the exposure.The activities of glutathione S-transferase（GST）,superoxide dismutase（SOD）and catalase（CAT）in the hepatic system of Carassius auratus could be induced significantly.The activity of GST was the most sensitive,and it could be induced remarkably in all dose groups.Even at 0.5g·L-1,it reached the highest level（606%compared with that in the control level）.The activity of SOD increased first and then decreased,and was significantly suppressed in the the 50.0g·L-1dose group.The activity of CAT was significantly induced in 0.5g·L-1dose group,and the highest inducement in the 2.5g·L-1dose group was 4.86 times as much as that in the control group.It was concluded that the activities of SOD and CAT,especially GST in the hepatic system of Carassius auratus were sensitive,and they could be the early monitoring index for the presence of oil pollution in aquatic ecosystems.

Keywords：Carassius auratus；crude-oil-contaminated soil；ecotoxicity；antioxidant defense system；aquatic environment

1 引言（Introduction）

石油是水體和土壤生態系統的代表性污染物.有關石油污染對魚類等水生生物的毒性效應及其……