海河悬浮颗粒物影响阿特拉津对斑马鱼的急性毒性研究

Acute toxicity of atrazine to Brachydaniorerio under the effect of suspended sediments in Haihe River

悬浮颗粒物对有机污染物的吸附降低了其表观生物富集系数,这一过程是否同时能够减弱有机污染物对水生生物的毒性却少有报道.因此,本研究选取海河干流二道闸沉积物为悬浮颗粒物,以阿特拉津为目标污染物,斑马鱼为目标生物,进行急性毒性试验.结果表明,无悬浮颗粒物时,阿特拉津对斑马鱼的96 h半致死浓度(96h-LC50)为29.06 mg·L-1,95%置信区间为24.41~40.70 mg·L-1,悬浮颗粒物浓度为7500mg·L-1和15000 mg·L-1时这一指标分别为30.74 mg·L-1和39.51 mg·L-1,对应的95%置信区间分别为27.17~40.91 mg·L-1和30.43~126.93 mg·L-1.并且无悬浮颗粒物、7500 mg·L-1悬浮颗粒物、15000 mg·L-1悬浮颗粒物3组染毒系列中出现的最大无效应浓度分别为3、9和15 mg·L-1.研究表明,悬浮颗粒物的存在降低了阿特拉津对斑马鱼的急性毒性.

Suspended sediments can decrease apparent bioconcentration factor of organic pollutants through adsorption. However,it is not clear whether this process can weaken the toxicity of organic pollutants to non-target aquatic organisms. Sediments from Erdaozha,Haihe River were chosen as suspended sediments with atrazine as target pollutant and Brachydaniorerio as target organism to conduct the acute toxic experiment. Results show that without suspended sediments,the 96 h-LC50 of atrazine to Brachydaniorerio is 29. 06 mg·L- 1with 95% confidence interval of 24. 41 ~ 40. 70 mg·L- 1.When suspended sediments are 7500 mg·L- 1and 15000 mg·L- 1,the 96 h-LC50 are 30. 74 mg·L- 1and 39. 51 mg·L- 1,respectively,and their corresponding confidence intervals are 27. 17 ~ 40. 91 mg·L- 1and 30. 43 ~ 126. 93 mg·L- 1,respectively. The NOECs of the three contaminate series above are 3,9 and 15 mg·L- 1,respectively. Suspended sediments can weaken the acute toxic of atrazine to Brachydaniorerio.