Beijing Advanced Innovation Center for Food Nutrition and Human Health, Department of Applied Chemistry, China Agricultural University, Beijing, 100193, PR China.
College of Sciences, China Agricultural University, PR China.
Chemosphere. 2019 Jul;226:520-533. doi: 10.1016/j.chemosphere.2019.03.140. Epub 2019 Mar 26.
Hexaconazole and epoxiconazole are the worldwidely used fungicides. However, limited information is known about the toxicological effects of their enantiomers on aquatic organisms. In this study, zebrafish were separately exposed to 100 and 1000 μgL hexaconazole and epoxiconazole enantiomers for 21 d H NMR-based metabolomics analysis showed that the exposure of low and high dose of hexaconazole enantiomers altered energy metabolism, lipid metabolism and amino acid metabolism of zebrafish, with the different metabolic profiles resulted from the same dose of (+)-hexaconazole and (-)-hexaconazole. Similar to hexaconazole enantiomers, the metabolic profiles, including the changes related to energy metabolism, lipid metabolism and amino acid metabolism, were demonstrated in low and high dose epoxiconazole enantiomers treatment groups. There are differences in the metabolic profiles of zebrafish between exposed to (+)-epoxiconazole and (-)-epoxiconazole of the same dose. The results of histological examination revealed that the exposure of both enantiomers for hexaconazole and epoxiconazole resulted in the similar histopathological changes. The exposure of hexaconazole and epoxiconazole enantiomers at low and high dose resulted the vacuolization and swell in the liver of the female and male zebrafish. Compared to female zebrafish, more liver damage was found in male zebrafish in the hexaconazole enantiomers exposure groups. The reduction of spermatids was observed in hexaconazole and epoxiconazole enantiomers treatment groups of both doses. Hexaconazole enantiomers exposure of low and high dose resulted the increase in the number of mature eggs, while such effect was not observed in epoxiconazole enantiomers exposure groups. Hexaconazole and epoxiconazole enantiomers exposure resulted in no changes in brains of female and male zebrafish. As a result, both triazole-based chiral bactericides, hexaconazole and epoxiconazole, have similar toxicological effects but their mechanisms of action are not exactly the same. The above results will play an important part in making the differences in toxic effects of hexaconazole and epoxiconazole enantiomers clear. What's more, it is an indispensable part for an integrated environmental risk assessment.
六氯环己烷和环氧氯丙烷是世界范围内广泛使用的杀菌剂。然而，关于它们的对映体对水生生物的毒理学影响的信息有限。在这项研究中，斑马鱼分别暴露于 100 和 1000 µgL 的六氯环己烷和环氧氯丙烷对映体 21 天。基于 1H NMR 的代谢组学分析表明，低剂量和高剂量的六氯环己烷对映体改变了斑马鱼的能量代谢、脂质代谢和氨基酸代谢，而相同剂量的 (+)-六氯环己烷和 (-)-六氯环己烷导致不同的代谢谱。与六氯环己烷对映体类似，低剂量和高剂量环氧氯丙烷对映体处理组均显示出代谢谱的变化，包括与能量代谢、脂质代谢和氨基酸代谢相关的变化。在暴露于相同剂量的 (+)-环氧氯丙烷和 (-)-环氧氯丙烷的斑马鱼中，代谢谱存在差异。六氯环己烷和环氧氯丙烷对映体的暴露导致雌、雄斑马鱼的组织病理学变化相似。与雌斑马鱼相比，在六氯环己烷对映体暴露组中，雄斑马鱼的肝脏损伤更严重。在低剂量和高剂量的六氯环己烷和环氧氯丙烷处理组中，均观察到精子减少。低剂量和高剂量的六氯环己烷对映体暴露导致成熟卵子数量增加，而在环氧氯丙烷对映体暴露组中未观察到这种效应。六氯环己烷和环氧氯丙烷对映体暴露对雌、雄斑马鱼的大脑没有影响。因此，两种三唑类手性杀菌剂六氯环己烷和环氧氯丙烷具有相似的毒理学效应，但作用机制并不完全相同。上述结果将有助于阐明六氯环己烷和环氧氯丙烷对映体的毒性作用差异。此外，这也是综合环境风险评估不可或缺的一部分。
