Subchronic toxicity of sublethal oral doses of tolfenpyrad in rats

Abstract

Tolfenpyrad (TFP), a pyrazole-based pesticide, was evaluated for its sublethal effects on male Wistar rats following repeated oral administration for 60 days. The study aimed to assess changes in body weight, feed and water intake, and physiological responses across three dose levels (1/5th, 1/10th, and 1/20th of LD50). No overt toxicity symptoms or mortality were observed; however, noticeable changes included coarser body coats, redness around the mouth, and altered fecal consistency, which became more evident toward the end of the study. A significant, dose-dependent reduction in feed and water intake was observed, with the highest suppression in the 1/5th LD50 group. Correspondingly, weight gain was lower in the higher-dose groups, suggesting an impact on metabolism and physiological functions. These findings align with previous reports on pesticide-induced appetite suppression, neurotoxic effects, and growth inhibition in rodents. The study underscores the need for further research into the mechanistic pathways underlying these effects and their potential implications for human health.