我国地表水新烟碱类杀虫剂对水生生物安全的威胁

Neonicotinoid Insecticides Threaten Surface Waters at the National Scale in China

针对我国新烟碱类杀虫剂(NNIs)使用量大且地表水中浓度逐渐上升的现状,基于物种敏感度分布法,利用危害商法和概率风险评价法评估了我国地表水中NNIs对淡水水生生物的单一和复合生态风险,并对我国地表水质监管NNIs提出了目标建议值.结果表明:①单一化合物,吡虫啉的急性危害最大,吡虫啉和啶虫脒的慢性危害较大,最敏感生物均为昆虫;②海南省是地表水NNIs浓度最高的地区,急慢性危害最大;③联合毒性的概率曲线表明,5种NNIs对5%淡水水生生物产生慢性联合毒性的概率高达92.12%,严重威胁我国水生生物的安全;④基于物种敏感度分布曲线得到毒性参考值,结合危害商和概率风险评价的结果,建议我国保护水生生物安全的地表水质监管目标值分别为吡虫啉0.01μg·L^(-1)、噻虫啉0.03μg·L^(-1)、啶虫脒0.04μg·L^(-1)、噻虫胺0.22μg·L^(-1)和噻虫嗪0.24μg·L^(-1).总之,我国地表水中NNIs浓度已经威胁到水生生物的安全,必须加强监管.

This study was conducted in response to the current situation in our country in which neonicotinoid pesticides(NNIs)are used in large quantities and their concentration in surface water is gradually increasing.Based on the species sensitivity distribution(SSD),the hazard quotient(HQ)and probabilistic risk assessment(PRA)were used to compare single and mixture risks of NNIs in the surface water in China.The target and recommended values of NNIs in China's surface water quality supervision were also presented.The results showed that:①in the single acute hazard assessment,imidacloprid(IMI)was the most harmful insecticide,and in the single chronic hazard assessment,imidacloprid(IMI)and acetamiprid(ACE)were more harmful.Furthermore,insects were the most sensitive creatures.②Hainan province was the region with the highest single acute and chronic hazard in the study area.③Based on the joint probability curves of five neonicotinoids,the probability in which 5%of species would be affected by long-term exposure was approximately 91.12%.Thus,the combined ecological risk of these five neonicotinoids cannot be ignored.④Based on the toxicity reference value from SSD and the combined results of HQ and PRA,the regulatory values of surface water quality in China were as follows:acetamiprid(ACE)0.04μg·L^(-1),clothianidin(CLO)0.22μg·L^(-1),imidacloprid(IMI)0.01μg·L^(-1),thiacloprid(THI)0.03μg·L^(-1),and thiamethoxam(THIA)0.24μg·L^(-1).In short,the concentration of NNIs in the surface water in China has threatened the safety of aquatic organisms,and its supervision must be improved.