Department of Pesticide Chemistry and Technology, Faculty of Agriculture, University of Alexandria, Alexandria, Egypt.
Mammalian and Aquatic Toxicology Department, Central Agricultural Pesticide Lab, Agricultural Research Center, Alexandria, Egypt.
Environ Sci Pollut Res Int. 2024 Nov;31(55):63747-63763. doi: 10.1007/s11356-024-35420-1. Epub 2024 Nov 6.
Aquatic organisms are simultaneously exposed to multiple hazardous chemicals that can be released into water bodies. The current study aimed to evaluate the effect of sublethal concentration (1/50 96 h-LC) of two formulated pesticides: ethoprophos, bispyribac-sodium, and their combination for 1, 2, 3, and 4 weeks on oxidative stress, genotoxic response, and gill morphology in Nile tilapia. This study is the first to demonstrate the toxic effects of ethoprophos and bispyribac-sodium mixture on the commercial important species, Oreochromis niloticus. The results showed that the 96 h-LC values of ethoprophos and bispyribac-sodium were 4.8 and 0.064 mg/L, respectively. Additionally, exposure to individual or combined pesticides induced a significant increase in the level of malondialdehyde (MDA), glutathione S-transferase (GST), and 8-hydroxy-2-deoxyguanosine (8-OHdG), as well as a notable decline in reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) levels at all time of exposure. Furthermore, there were alterations in ultrastructure of the gill samples, including erosive lesions on the primary and secondary lamellae, fusion of microridges, and excessive mucus secretions on the epithelium. The data clearly demonstrate that the negative effects of the tested compounds are time-dependent and are more severe in combination than in a single compound. Collectively, our results indicated that the interaction of ethoprophos and bispyribac-sodium might be largely synergistic and provide new insights into the molecular mechanisms of fish confronting these substances.
水生生物同时暴露于多种可能释放到水体中的有害化学物质中。本研究旨在评估亚致死浓度（1/50 96 h-LC）的两种配方农药：乙基丙磷、双丙吡草酸钠及其混合物对尼罗罗非鱼（Oreochromis niloticus）1、2、3 和 4 周的氧化应激、遗传毒性反应和鳃形态的影响。这是首次证明乙基丙磷和双丙吡草酸钠混合物对商业重要物种尼罗罗非鱼的毒性作用。结果表明，乙基丙磷和双丙吡草酸钠的 96 h-LC 值分别为 4.8 和 0.064 mg/L。此外，单独或联合使用这些农药会导致丙二醛（MDA）、谷胱甘肽 S-转移酶（GST）和 8-羟基-2-脱氧鸟苷（8-OHdG）水平显著升高，同时还原型谷胱甘肽（GSH）、超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和谷胱甘肽过氧化物酶（GPx）水平显著降低，所有暴露时间均如此。此外，鳃样本的超微结构也发生了改变，包括初级和次级鳃瓣的侵蚀性病变、微嵴融合以及上皮过度分泌黏液。数据清楚地表明，测试化合物的负面影响是时间依赖性的，且混合物的影响比单一化合物更严重。总的来说，我们的结果表明，乙基丙磷和双丙吡草酸钠的相互作用可能在很大程度上是协同的，并为鱼类应对这些物质的分子机制提供了新的见解。
