Monocrotophos (MCP) is a highly toxic and broad-spectrum pesticide extensively used for agricultural and household purposes. The present study was aimed to evaluate the genotoxicity and alterations in the biochemical and physiological conditions induced by monocrotophos in a non-target organism, an estuarine bivalve, Donax incarnatus. The bivalves were exposed to three sub-lethal concentrations (6.8, 13.7, and 27.45 ppm) of MCP for a period of 72 h. DNA damage was assessed using the comet assay. Oxidative stress was analyzed using catalase, glutathione peroxidase, and superoxide dismutase. Neurotoxicity was evaluated using the acetylcholinesterase assay (AChE) and the physiological condition was assessed using the condition index (CI). A significant concentration-dependent increase of DNA damage was observed as well as a decline in the activities of the antioxidant enzymes. However, a decrease in DNA damage was observed with advancing time. A significant decrease of AChE activity and CI was observed in the bivalves exposed to MCP. Positive correlations were also observed between DNA damage and the antioxidant enzymes whereas negative correlations were observed between AChE and the antioxidant enzymes indicating MCP toxicity mediated by oxidative stress.

久效磷（MCP）是一种剧毒的广谱农药，广泛用于农业和家庭用途。本研究旨在评估久效磷在非靶标生物，河口双壳类，Donax incarnatus中引起的遗传毒性以及生化和生理条件的改变。将双壳类动物暴露于三种亚致死浓度（6.8、13.7和27.45 ppm）的MCP中72小时。使用彗星试验评估DNA损伤。使用过氧化氢酶，谷胱甘肽过氧化物酶和超氧化物歧化酶分析氧化应激。使用乙酰胆碱酯酶测定法（AChE）评估神经毒性，并使用条件指数（CI）评估生理状况。观察到DNA损伤的浓度依赖性显着增加以及抗氧化酶活性的下降。但是，随着时间的推移，观察到DNA损伤的减少。在暴露于MCP的双壳动物中，AChE活性和CI显着降低。