消油剂对海湾扇贝(Argopecten irradians)的急性毒性效应

本研究以海湾扇贝(Argopecten irradians)为研究对象, 通过96 h半静水毒性实验，探讨了消油剂、0号柴油分散液(WAF)与0号柴油乳化液(CEWAF)对海湾扇贝24 h、48 h、72 h、96 h急性毒性效应。结果显示，消油剂对海湾扇贝的24 h、48 h、72 h和96 h半致死浓度(95%可信限)分别为1905(1570-2451 mg/L)、1293(1070-1556 mg/L)、1015(721-1348 mg/L)、846 mg/L(660-1020 mg/L)；WAF对海湾扇贝的24 h、48 h、72 h和96 h半致死浓度(95%可信限)分别为36.57(29.42-48.96 mg/L)、23.10(21.07-25.39 mg/L)、14.99(13.66-16.41 mg/L)、11.31 mg/L(8.37-14.47 mg/L)；CEWAF对海湾扇贝的24 h、48 h、72 h和96 h半致死浓度(95%可信限)分别为12.71(10.78-15.55 mg/L)、8.51 (7.99-9.07 mg/L)、6.56(4.46-7.74 mg/L)、5.42 mg/L(4.51-6.29 mg/L)。消油剂、0号柴油分散液、0号柴油乳化液对海湾扇贝96 h安全浓度分别为84.6、1.13、0.54 mg/L。随着实验时间的延长，消油剂、WAF和CEWAF对海湾扇贝的半致死浓度(LC50)均呈逐渐降低之势，半致死浓度与时间呈幂函数关系，其关系式分别为y=12242x–0.583、y=564.37x–0.848、y=89.987x–0.613。在受试溶液中暴露相同时间，海湾扇贝的半致死浓度从高到低依次为消油剂、WAF和CEWAF，说明CEWAF对海湾扇贝的毒性大于消油剂和WAF，这对于在养殖海区使用消油剂处理溢油事故具有重要的指导意义。

The Acute Toxicity of Dispersant and Chemically Dispersed Oil on the Argopecten irradians

Chemical dispersant has rapidly gained popularity in controlling unwanted oil spill in the aquatic environment, however, it exerts adverse effects on the aquatic organisms. The acute toxicity of chemical dispersant on fish, algae and zooplanktons has been widely investigated in previous studies. In the contrast, the acute toxic effects on shellfish remains unclear. In this study, we examined the acute toxic effects of chemical dispersant, dispersed 0 diesel oil (WAF) and chemically dispersed 0 diesel (CEWAF) on A. irradians. The test was performed within 96h, and the concentrations of chemical dispersant, WAF and CEWAF ranged from 0.50-3.00, 5.88-58.80 and 3.54-20.00 mg/L respectively. The LC50 values (within 95% confidence intervals) of dispersant in A. irradians were 1905, 1293, 1015 and 846 mg/L in the time courses of 24 h, 48 h, 72 h and 96 h respectively. The LC50 values of WAF were 36.57, 23.10, 14.99 and 11.31 mg/L corresponding to different time courses, and the values of CEWAF were 12.71, 8.51, 6.56 and 5.42mg/L respectively. As the time course increased from 24 h to 96 h, the median lethal concentrations (LC50) of chemical dispersant, WAF and CEWAF were decreased accordingly. The median lethal concentration and time course appeared to be highly correlated. The functions of LC50 (y) of dispersant, WAF and CEWAF against time (x) were y=12242x-0.583, y=564.37x-0.848, and y=89.987x-0.613 respectively. For the same exposure time, the order of the median lethal concentrations was dispersant > WAF > CEWAF, suggesting that the acute toxicity of CEWAF on A. irradians was higher than dispersant and WAF.