Technical imidacloprid was evaluated for its effect on ovarian morphology, hormones and antioxidant enzymes in female rats after 90 days oral exposure. Activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and levels of reduced glutathione (GSH) and lipid peroxidation (LPO) were estimated in ovary and Luteinizing hormone (LH), Follicle stimulating hormone (FSH) and progesterone levels were estimated in serum of rats after oral administration of imidacloprid (5, 10, and 20 mg/kg/day) for 90 days. Decreased ovarian weight together with significant patho-morphological changes in follicles, antral follicles and atretic follicles were observed at 20mg/kg/day. Imidacloprid at 5 and 10 mg/kg/day did not produce any significant changes in ovarian morphology, hormones and antioxidant status of ovary. However, 20 mg/kg/day dose produced signi-ficant changes in SOD, CAT, GPx, GSH, and LPO. Similarly, significant decrease in the levels of LH and progesterone and increased levels of FSH were observed at 20 mg/kg/day dose level. Therefore, it is concluded that imidacloprid at 20mg/kg/day dose level has produced significant toxicological impact on ovary of female rats as evident by patho-morpholo-gical changes, hormonal imbalance and generating oxidative stress and can be considered primarily as Lowest Observed Effect Level (LOEL) for chronic study.

Kapoor et al.; Food and Chemical Toxicology; 2011; 49; 3086–3089.

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