Induction of gonadal toxicity to female rats after chronic exposure to mancozeb.

Mancozeb, a fungicide of ethylenebisdithiocarbamate group was orally administered at doses of 500, 600, 700 and 800 mg/kg body weight/day to normal virgin rats of Wistar strain for 30 days. The vaginal smear and body weight of the rats were recorded daily and rats were sacrificed on 31st day. Estrous cycle was effected by showing a significant decrease in the number of estrous cycle, duration of proestrus, estrus and metestrus with concomitant significant increase in the duration of diestrus in all the mancozeb treated groups when compared with controls. There were a significant decrease in the number of healthy follicles and a significant increase in the number of atretic follicles in all the mancozeb treated groups when compared with controls. The histologic observation of the ovary revealed the presence of less number of corpora lutea and the size of the ovary was also reduced in high doses of mancozeb treated rats. There was a significant increase in the thyroid weight in all the mancozeb treated rats except in 500 mg/kg/d. In rats treated with 500 mg/kg/d showed a significant increase in the level of total lipids in the liver. In rats treated with 600 mg/kg/d mancozeb showed a significant decrease in the levels of glycogen and total lipids in the uterus and total lipids in the liver. In rats treated with 700 mg/kg/d showed a significant decrease in the levels of protein in ovary, glycogen, total lipids, phospholipids and neutral lipids in the uterus and a significant increase in the levels of phospholipids, neutral lipids in the ovary and total lipids, phospholipids and neutral lipids in the liver. In rats treated with 800 mg/kg/d showed a significant decrease in the levels of protein and glycogen in the ovary and protein, glycogen, total lipids, phospholipids and neutral lipids in the uterus and a significant increase in the levels of total lipids, phospholipids and neutral lipids in the ovary and liver when compared with controls. These observed effect of mancozeb on the estrous cycle, follicles and biochemical constituents may be due to imbalance in the hormone or toxic effect.