异丙隆原药慢性毒性研究

Study on Chronic Toxicity of Isoproturon

目的为了解异丙隆原药的慢性毒性，提出其慢性最小有害作用剂量（LOAEL）和无害作用剂量（NOAEL）。方法480只SD种雄性和雌性大鼠（体重110～140g）分为4组，3个染毒组分别喂饲染毒异丙隆原药50．0mg／（kg·d）（高剂量组）、5．0mg／（kg·d）（中剂量组）和0．5mg／（kg·d）（低剂量组），对照组喂饲正常饲料，历时2a；观察大鼠日常表现、检测体重和饲料消耗量；检查了解解剖、病理、血液学、血液生化和尿液等指标的改变。结果高剂量组雌性和雄性大鼠的体重增长分别从试验第6周和第11个月开始减慢（P〈0．01）；高、中两剂量组雄性大鼠肝脏肿大，肝细胞水肿样变性和脂肪变性。结论异丙隆原药对雌性和雄性大鼠慢性毒性的LOAEL分别为50．0mg／（kg·d）和5．0mg／（kg·d），而NAOEL为0．5mg／（kg·d）。

Objective To observe the chronic toxicity of isoproturon and to provide the lowest observed adverse effect level（LOAEL）and no observed adverse effect level（NOAEL）. Methods 480 male and female SD rats weighing 110-140 g were divided into 4 groups. 3 exposed groups were fed with feedstuff containing high dosage isoproturon [50.0 mg/（kg · d）], medium dosage [5. 0 mg/（kg · d）] and low dosage[0.5 mg/（kg ·d）] respectively for 2 years. The control group was fed with normal feedstuff. The daily behavior was observed. The body weight and feed consumption were recorded. The changes in gross anatomy, histopathology, hematology, blood biochemistry and urinalysis were examined and analyzed. Results The body weight growth of rats in the high dosage group started to decline since the 6th week for female rats and the llth month for male rats （P〈0.01）. The hepatomegaly showing hydropic degeneration and fatty degeneration was observed in male rats of high and medium dosage groups. Conclusions The LOAELs of chronic toxicity of isoproturon are 50.0 mg/（kg · d） for female rats and 5.0 mg/（kg · d） for male rats, while the NOAEL is 0.5 mg/（kg · d）.