手性农药丁氟螨酯对斑马鱼胚胎的选择性发育毒性

近年来丁氟螨酯（CYF）对非靶标生物的发育毒性已成为一个值得关注的问题，但其对水生生物的对映选择性效应尚不清晰.为评估丁氟螨酯对斑马鱼胚胎的对映选择性毒性，通过96 h的暴露试验，研究了梯度浓度的丁氟螨酯消旋体及对映体对斑马鱼胚胎的急性毒性.此外，试验还研究了丁氟螨酯对斑马鱼胚胎孵化率、卵黄囊水肿、心包囊水肿和身体弯曲的影响.根据急性毒性结果可知，毒性大小为S-CYF > Rac-CYF > R-CYF，其中S-CYF的毒性是R-CYF的2.3倍.72 hpf，500 mg·L^-1的S-CYF可显著诱导胚胎产生卵黄囊水肿（YSE）、体轴弯曲（CB）等畸形效应（p<0.05），而Rac-CYF降低了斑马鱼胚胎的孵化成功率.在本研究中发育毒性效应结果与急性毒性结果一致，均为S-CYF > Rac-CYF > R-CYF，表明丁氟螨酯对斑马鱼胚胎存在显著的对映选择性发育毒性，研究结果为丁氟螨酯的环境风险评估提供了理论依据.

Enantioselective developmental toxicity of chiral cyflumetofen to zebrafish embryos

Although the developmental toxicity of cyflumetofen (CYF) to non-target organisms has become a significant concern in recent years, its enantioselective effects on aquatic organisms are poorly understood. To evaluate the enantioselective toxicity of CYF on zebrafish, zebrafish embryos were exposed to a series of isometric concentrations of two CYF enantiomers and the CYF racemate (Rac) for 96 h. In addition, the effect of three compounds on hatching rate, yolk sac edema, pericardial edema, and curved body axis were investigated. According to the acute toxicity results, S-CYF and Rac-CYF were higher than R-CYF, the toxicity of S-CYF was 2.3 times higher than R-CYF. At 500 mg·L^-1, and the S-CYF could significantly induce developmental abnormities including yolk sac edema, pericardial edema, curved body axis (p<0.05) at 72 hpf, while only the Rac-CYF could decrease the hatching rate. It''s been noticeable a regulation was apparent in this study, the developmental toxicity was consistent with acute toxicity (S-CYF > Rac-CYF > R-CYF). This work demonstrated the obvious of enantioselectivity in developmental toxicity of CYF to zebrafish embryos, which could be considered in environmental risk assessment.