A review on aquatic ecotoxicity of profenofos with reference to environmental fate and impact on fish

Abstract

Profenofos (PFF), a widely used organophosphorus insecticide in agriculture, has raised serious environmental concerns due to its persistence and toxicity in aquatic ecosystems. This review critically examines the environmental fate, transformation pathways, and ecotoxicological effects of PFF, with a particular focus on fish. PFF enters aquatic environments through runoff, leaching, and direct application, where it undergoes hydrolysis and microbial degradation, producing metabolites such as 4-bromo-2-chlorophenol and dichlorvos. These compounds exhibit bioaccumulative and toxic properties, affecting key physiological systems in aquatic organisms. As sensitive bioindicators, fish experience a range of toxic effects, including oxidative stress, neurotoxicity, impaired respiration, reproductive dysfunction, and behavioral anomalies, even at sublethal concentrations. The compound’s potential for biomagnification poses risks to higher trophic levels, including piscivorous birds and humans. This review identifies neurotoxicity, reproductive failure, and metabolic disruption in fish as the most prominent adverse outcomes of PFF exposure. However, limited data on chronic low-dose exposure, trophic transfer dynamics, and endocrine disruption mechanisms represent key knowledge gaps that require further investigation. Despite existing regulations, gaps persist in long-term monitoring, risk assessment, and identifying safe alternatives. This review emphasises the urgent need for integrated pest management (IPM), enhanced pesticide formulations, and stricter environmental policies to mitigate the ecological impacts of PFF and protect aquatic biodiversity.