Methomyl (MET) is a carbamate pesticide whose prolonged exposure has been associated with systemic toxicity in mammals. The reproductive system and adrenal glands are among the most sensitive targets of chemical-induced oxidative imbalance. The aim of this study was to evaluate the effects of subchronic exposure to MET on oxidative stress and histological damage in the reproductive system and adrenal glands of adult male rats. Animals were randomly divided into two groups: the control group and the MET-treated group, which received a daily oral dose of MET (1mg/kg body weight) for 90 consecutive days. Histopathological analysis revealed multiple types of tissue damage characterized by degenerative and necrotic lesions in the epididymis, accessory sex glands and adrenal glands in the MET-treated group. These alterations were associated with oxidative stress, as evidenced by a significant increase in malondialdehyde, a marker of lipid peroxidation, along with a decrease in glutathione levels and reduced activity of antioxidant enzymes such as glutathione S-transferase and glutathione peroxidase in the affected organs. This study provides compelling evidence that 90-day exposure to MET induces histological damage in the reproductive system and adrenal glands, potentially mediated by disrupted redox homeostasis in these tissues.

KEY WORDS: Methomyl; Subchronic toxicity; Oxidative stress; Reproductive organs; Adrenal glands.