生物杀虫剂印楝素的亚慢性毒性

Subchronic Toxicity of Biopesticide Azadirachtin (AZ)

目的评价以印楝中提取的印楝素(AZ)为生物杀虫有效成分杀虫剂的亚慢性毒性,为AZ类杀虫剂的安全使用和管理提供科学依据。方法用AZ(20%原药)含量分别为0,0.04%,0.20%和1.00%的饲料喂饲雄性和雌性Wistar大鼠90 d。观察动物表现,记录动物体重和食物消耗量,进行血常规、血清生化、尿常规和解剖及组织病理学检查。结果动物表现、动物体重、食物消耗量、尿常规分析及组织病理学等均未显示与受试物处理相关的改变。染毒结束(90 d)时,雄性高剂量组红细胞(RBC)总数和血红蛋白(Hb)含量降低,雌性高剂量组Hb降低;雄性高、中剂量组血清总蛋白(TP)含量增高,雌性高、中剂量组碱性磷酸酶(ALP)减少,胆固醇(CHO)增高,TP增高,其他生化检测指标未发现有毒理学意义的改变。雄性高、中剂量组肝脏系数和高剂量组肾脏系数与对照组比较明显增高,雌性高、中剂量组肝脏系数增高。结论AZ(20%原药)亚慢性毒性相对较低,对造血系统和肝脏、肾脏可能有潜在的影响,对肾脏的影响推测为功能性改变。根据结果推断,0.04%AZ(20%原药)为本研究的最小可见有害作用水平(lowest observedadverse effect level,LOAEL),雌、雄性大鼠分别为每日50.2 mg/kg和45.6 mg/kg。

Objective To study the subchronic toxicity of azadirachtin （AZ）, a biopesticide （or bioinsecticide） extracted from neem tree, and determine its safety for use as a pesticide. Methods AZ（20% active compound as stock solution）was orally administered to male and female rats at dosages of 0, 0.04%, 0.20% and 1.00% in the diet for 90 days. Clinical signs, body weights, organ weights, food consumption, hematology, serum biochemistry, urinalysis and histopathology were observed and recorded. Results No treatment related effects were observed in the clinical signs, body weights, food consumption, urinalysis, and histopathology during the study. The RBC and Hb concentration in males significantly decreased in the high-dose group, and the Hb concentration in females significantly decreased in the high-dose group after 90 days of treatment. TP concentration in serum of males significantly increased in the mid- and high-dose groups. ALP activity in females significantly decreased in the mid- and high-dose groups. TP concentration and CHO concentration in females increased in the mid- and high-dose groups. Other treatment related changes of serum chemistry parameter were not observed after 90 days of treatment. The liver/body weight ratio in males and females significantly increased in the mid- and high-dose groups, and the kidney/body weight ratio in males significantly increased in the high-dose group. Conclusions The results suggests that the subchronic toxicity of AZ （20% active compound） are relatively low. AZ （20 % active compound） may have potential impacts on haematogenesis system, liver and kidney. The induction of kidney abnormalities may only be indicative of renal dysfunction. Based on the present toxicity data, 0. 04% was determined to be the lowest observed adverse effect level（LOAEL）, converting into 50.2 and 45.6 mg/kg · day for female and male rats, respectively.