新烟碱类和阿维菌素类药剂对蚯蚓的急性毒性效应

Acute Toxicity of Neonicotinoids and Avermectins to Earthworm,Eisenia foetida

为评价农药对蚯蚓的生态风险提供基础数据,采用滤纸法和人工土壤法测定了新烟碱类和阿维菌素类药剂对蚯蚓的急性毒性效应。滤纸法测定结果表明,吡虫啉、啶虫脒、烯啶虫胺、氯噻啉和噻虫啉5种新烟碱类药剂对蚯蚓的LC50值范围为0.0089(0.0075～0.010)μg·cm-2～0.44(0.34～0.56)μg·cm-(248h结果),噻虫嗪对蚯蚓的LC50值在24h和48h均大于62.91μg·cm-2;阿维菌素、依维菌素和甲氨基阿维菌素苯甲酸盐3种阿维菌素类药剂对蚯蚓的LC50值范围为4.52(3.71～5.50)μg·cm-2～22.76(18.68～27.73)μg·cm-(248h结果)。人工土壤法测定结果表明,5种新烟碱类药剂(除噻虫嗪外)对蚯蚓的LC50值范围为1.54(1.43～1.71)mg·kg-1～17.29(16.44～19.41)mg·kg-(114d结果),噻虫嗪对蚯蚓的LC50值在第7d和14d均大于1200mg·kg-1;3种阿维菌素类药剂对蚯蚓的LC50值范围为27.93(26.04～29.81)mg·kg-1～175.33(162.82～188.91)mg·kg-(114d结果)。根据《化学农药环境安全评价试验准则》,吡虫啉、啶虫脒和烯啶虫胺对蚯蚓属于中毒级,其他的药剂对蚯蚓属于低毒级。

To evaluate ecological risk of pesticides to earthworm,Eisenia foetida,filter paper testing and artificial soil testing methods were applied to determine the acute toxicity of neonicotinoids and avermectins to E. foetida. The results of filter paper test showed that the LC50 values（48 h contact toxicity） ranged from 0.008 9（0.007 5-0.010） μg·cm^-2 to 0.44（0.34-0.56） μg·cm^-2 for imidacloprid,acetamiprid,nitenpyram,imidaclothiz and thiacloprid to E. foetida. The 24 h and 48 h LC50 values of thiamethoxam to E. foetida were higher than 62.91 μg·cm^-2. Moreover,the LC50 values of abamectin,ivermectin and emamectin benzoate to E. foetida were between 4.52（3.71-5.50） μg·cm^-2 and 22.76（18.68-27.73） μg·cm^-2（48 h results）. The results of artificial soil test showed that the LC50 values of neonicotinoids（except for thiamethoxam） to E. foetida ranged from 1.54（1.43-1.71） mg·kg^-1 to 17.92（16.44-19.41） mg·kg^-1（14 d results）,and the LC50 values of thiamethoxam to E. foetida were more than 1 200 mg·kg^-1 after 7 d and 14 d. Moreover,the LC50 values of avermectin insecticides to E. foetida were between 27.93（26.04-29.81） mg·kg^-1 and 175.33（162.82-188.91） mg·kg^-1 after 14 d. Our results indicated that imidacloprid,acetamiprid and nitenpyram have moderate toxicity,while other pesticides have low toxicity to E. foetida,based on the classification standard of the Testing Guidelines for Environmental Safety Evaluation of Chemical Pesticides.