We aimed to understand the toxic effects of two crop protecting agents, organophosphate pesticide, chlorpyrifos (CPF) and fertilizer, urea (U), and their binary mixtures at sublethal concentrations for 28-d in a freshwater fish Channa punctata with a battery of biochemical biomarkers in gill and liver. The study has practical value as such mixtures, so often present together in water in the agro-intensive areas, might be predicted to cause cocktail effects. Both CPF and U inhibited AChE, augmented SOD, CAT, GPx activities, and caused lipid peroxidation and depletion in tissue macromolecules in a concentration and duration-dependent manner. While U alone had less severe effects compared to CPF treatments, complex interactions were observed for three combination doses (1CPF + 1U, 2CPF + 1U, 1CPF + 2U). In their mutual effects, antagonism prevailed over other interactions when CPF and U were in equal proportion in the mixture, while synergism was observed for AchE and key antioxidant enzymes when more U was in the mixture. The present study concluded that urea in water bodies might impart adverse effects in combination with pesticides in non-target aquatic organisms such as fish, and there should be a restriction in its excessive usage.

我们旨在了解两种作物保护剂，即有机磷农药，毒死rif（CPF）和化肥，尿素（U）及其在低致死浓度下二元混合物在淡水鱼Channa punctata中的毒害作用28天。在a和肝脏中带有一系列生化生物标记物。该研究具有实用价值，因为这种混合物通常在农业密集地区的水中共同存在，可能会导致鸡尾酒效应。CPF和U均以浓度和持续时间依赖性方式抑制AChE，增加SOD，CAT，GPx活性，并引起组织大分子脂质过氧化和耗竭。尽管与CPF治疗相比，单独使用U的严重程度较轻，但在三种联合剂量（1CPF + 1U，2CPF + 1U，1CPF + 2U）中观察到了复杂的相互作用。在互作用中，当CPF和U在混合物中的比例相等时，拮抗作用胜过其他相互作用，而当混合物中存在更多的U时，则观察到AchE和关键抗氧化酶的协同作用。