16种农药制剂对意大利蜜蜂的急性毒性及初级风险评估

Acute Toxicity and Risk Assessment of 16 Pesticide Formulations to Apis mellifera

为评价常用化学农药对意大利蜜蜂的毒害作用,采用饲喂法和微量点滴法分别测定了16种农药制剂对意大利蜜蜂成年工蜂的急性经口毒性和急性接触毒性,并结合田间推荐施用量计算风险商值,进行了初级风险评估。结果表明,供试8种杀虫剂均为高毒,其中,除10%高效氯氰菊酯水乳剂风险商值为0.89,<1外,其余7种制剂风险商值均>1,风险不可接受。除草剂中,45%莎稗磷乳油为中毒,急性经口和急性接触的48 h半致死剂量(48 h-LD_(50))分别为5.90μg a.i.·蜂^(-1)和5.42μg a.i.·蜂^(-1),风险商值>1,风险不可接受。其余4种除草剂和3种杀菌剂均为低毒,风险商值均<1,风险可接受。15%高效氯氟氰菊酯·噻虫嗪悬浮剂和10%高效氯氟氰菊酯·噻虫胺悬浮剂2种混配制剂相比于单剂,对意大利蜜蜂的急性毒性和风险均升高。建议对高风险制剂进一步开展高级风险评估或采取错开作物花期施用等规避措施降低对蜜蜂的风险。

The acute oral toxicity and acute contact toxicity to adult bees of Apis mellifera about 16 chemical pesticide formulations were tested using oral-feeding and topical application methods in order to evaluate the toxic effects of common pesticides.The first-tier risk assessment was characterized by the risk quotient(RQ)combined with the recommended application rates.The results showed 8 insecticides exhibited high toxicity.The RQ values of 7 formulations were greater than 1 except 0.89 of 10%beta-cypermethrin EW and the risk was unacceptable.45%anilofos EC,one of the herbicides,exhibited moderate toxicity,the 48 h median lethal dose(48 h-LD_(50))of acute oral toxicity and acute contact toxicity were 5.90μg a.i.·bee^(-1)and 5.42μg a.i.·bee^(-1),respectively.The RQ values were greater than 1 and the risk was unacceptable.The remaining 4 herbicides and 3 fungicides were all low toxicity,and the RQ values were less than 1 so the risk was acceptable.Both the 15%lambda-cyhalothrin·thiamethoxam SC and the 10%lambda-cyhalothrin·clothianidin SC mixtures exhibited higher toxicity and risk to Apis mellifera than the single agents.Therefore,higher tier risk assessment or risk avoidance measures such as avoiding application at flowering stage should be carried out to reduce the risk to honeybees.