Pyriproxyfen (2-[1-methyl-2-(4-phenoxyphenoxy) ethoxy] pyridine) (PPF), a pyridine-based pesticide widely used to control agricultural insect pests and mosquitoes in drinking water sources. However, its ecotoxicological data is limited in aquatic vertebrates particularly in fish. Hence, the present study aimed to evaluate the adverse effect of PPF in zebrafish embryo development (Danio rerio). In order to investigate the impact of PPF, embryos were exposed to 0.16, 0.33 and 1.66 μg/mL (0.52, 1.04 and 5.2 μM, respectively) for 96 hpf and various biomarker indices such as developmental toxicity (edema formation, hyperemia, heart size and scoliosis), oxidative stress (reactive oxygen species (ROS), lipid peroxidation (LPO) and nitric oxide (NO)), antioxidant responses (superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), glutathione peroxidase (GPx) and reduced glutathione (GSH)), biochemical (lactate dehydrogenase (LDH) and acid phosphatase (AP)), neurotoxicity (acetylcholinesterase (AChE)), genotoxicity (apoptosis and DNA damage) and histopathological changes were determined. The results showed that severe developmental deformities and changes in heart rate were observed in embryos treated with highest (1.66 μg/mL) concentration than the control (P < 0.05). Heart size measurement showed that, significant change in heart size (P < 0.01) was observed in embryos of 96 hpf only at 1.66 μg/mL PPF exposure. The oxidative stress was apparent at highest test concentration (1.66 μg/mL) as reflected by the elevated ROS, LPO and NO and changes in antioxidant enzyme activities including SOD, CAT, GST and GPx (P < 0.05). Besides, GSH level and AChE activity were significantly lowered in 1.66 μg/mL PPF exposed group than the control. After 96 hpf of PPF exposure, no significant changes were found in AP activity whereas, a biphasic response was observed in the LDH activity. There was no genotoxic effect in embryos exposed to PPF at 0.16 and 0.33 μg/mL, while significant (P < 0.05) DNA damage and apoptosis were found in 1.66 μg/mL treated group. Histopathological analysis revealed that exposure to PPF at 1.66 μg/mL resulted in thinning of heart muscles, pericardial edema and hyperemia while there was no obvious changes were observed in other treatment groups. Hence, the results of the present study demonstrate that PPF could cause adverse effect on early developmental stages of zebrafish at higher concentration.

吡咯烷芬（2- [1-甲基-2-（4-苯氧基苯氧基）乙氧基]吡啶）（PPF），一种基于吡啶的农药，广泛用于控制饮用水源中的农业害虫和蚊子。但是，其生态毒理学数据在水生脊椎动物中特别是在鱼类中是有限的。因此，本研究旨在评估PPF对斑马鱼胚胎发育（Danio rerio）的不利影响。）。为了研究PPF的影响，将胚胎分别暴露于0.16、0.33和1.66μg/ mL（分别为0.52、1.04和5.2μM）下96 hpf和各种生物标志物指数，例如发育毒性（水肿形成，充血，心脏大小）和脊柱侧弯），氧化应激（活性氧（ROS），脂质过氧化（LPO）和一氧化氮（NO）），抗氧化反应（超氧化物歧化酶（SOD），过氧化氢酶（CAT），谷胱甘肽S-转移酶（GST），谷胱甘肽测定过氧化物酶（GPx）和还原型谷胱甘肽（GSH），生物化学物质（乳酸脱氢酶（LDH）和酸性磷酸酶（AP）），神经毒性（乙酰胆碱酯酶（AChE）），遗传毒性（细胞凋亡和DNA损伤）和组织病理学变化。结果表明，在接受最高处理的胚胎中观察到严重的发育畸形和心率变化（1。浓度比对照浓度高66μg/ mL（P <0.05）。心脏大小测量表明，仅在1.66μg/ mL PPF暴露下，在96 hpf的胚胎中观察到心脏大小的显着变化（P <0.01）。氧化应激在最高测试浓度（1.66μg/ mL）时很明显，这是由ROS，LPO和NO升高以及抗氧化酶活性（包括SOD，CAT，GST和GPx）的变化所反映的（P <0.05）。此外，暴露于1.66μg/ mL PPF的组的GSH水平和AChE活性均显着低于对照组。PPF暴露96 hpf后，AP活性未见明显变化，而LDH活性则观察到双相反应。在暴露于PPF 0.16和0.33μg/ mL的胚胎中没有遗传毒性作用，而在1.66μg/ mL的治疗组中发现了显着的（P <0.05）DNA损伤和细胞凋亡。组织病理学分析显示，暴露于1.66μg/ mL的PPF会导致心肌变薄，心包水肿和充血，而其他治疗组则无明显变化。因此，本研究的结果表明，PPF可以在较高浓度下对斑马鱼的早期发育阶段产生不利影响。