沙蚕暴露于石油烃、Cu2+和Cd2+毒性效应及乙酰胆碱酯酶活性的响应

采用浓度梯度污染暴露室内模拟方法,研究了沙蚕（Perinereis aibuhitensis Grube）暴露于不同浓度的石油烃和重金属Cu²⁺、Cd²⁺的毒性效应及乙酰胆碱酯酶活性的响应.结果表明,石油烃和Cd²⁺、Cu²⁺对沙蚕均具有较强的毒性效应.暴露4 d和10 d后,石油烃LC₅₀分别为440和110 μg·L^-1,Cu²⁺分别为1 150和570 μg·L^-1,Cd²⁺分别为5 090和2 500 μg·L^-1,相应的生态毒性大小为：石油烃＞Cu²⁺＞Cd²⁺.在Cd²⁺、Cu²⁺污染暴露条件下,沙蚕体内乙酰胆碱酯酶活性受到一定程度的抑制,但抑制率均低于50％.而在石油烃污染暴露条件下,沙蚕体内乙酰胆碱酯酶活性受到显著抑制,最高抑制率可达90％以上;而且,其乙酰胆碱酯酶活性的变化与石油烃的浓度显著相关.可见,乙酰胆碱酯酶活性的变化可以作为生物标志物,较灵敏地反映出石油烃对沙蚕的污染效应及其毒害作用.

Toxic Effects of Petroleum Hydrocarbons, Copper and Cadmium on Polychaete Perinereis aibuhitensis Grube and on Its Responses in Acetycholinesterase Activity

Using the indoor simulating method of pollution exposure at various concentrations, the toxic effects of various concentrations of petroleum hydrocarbons (PHCs), copper (Cu2+) and cadmium (Cd2+) on the polychaete Perinereis aibuhitensis Grube and on its acetycholinesterase (AChE) activity were examined. The results indicated that petroleum hydrocarbons, Cu2+ and Cd2+ had the high toxicity to the polychaete Perinereis aibuhitensis Grube. After 4-day and 10-day exposure to petroleum hydrocarbons, Cu2+ and Cd2+, the value of LC50 were 440 and 110 microg x L(-1) for PHCs, 1 150 and 570 microg x L(-1) for Cu2+, 5 090 and 2 500 microg x L(-1) for Cd2+. In particular, PHCs had a stronger acute toxic effect than Cu and Cd. The AChE activity was inhibited, when the animal was exposed to Cd2+ and Cu2+, but the rate of inhibition was less than 50%. In particular, the AChE activity of the animal exposed to PHCs was significantly inhibited. The maximum rate of the inhibition by PHCs reached more than 90%. Moreover, the changes in the AChE activity significantly related with the concentration of PHCs. Thus, the index in the activity of AChE can sensitively reflect the toxic effects of PHCs on Perinereis aibuhitensis Grube as an important biomarker.