Heavy metals and herbicide are gaining serious environmental concern in aquatic toxicology due to its adverse effects on aquatic organisms especially amphibians. Accordingly, present study first time evaluated the acute toxicity of two heavy metals [arsenic (As3+) and chromium (Cr6+)] and a herbicide (Almix) to Indian skittering frog tadpole, Euphlyctis cyanophlyctis. The LC50 values of As, Cr and Almix for 24, 48, 72 and 96 h were 73.58, 56.31, 43.58 and 32.58 mg L-1; 326.68, 224.31, 171.92 and 141.99 mg L-1; and 1297.85, 1148.22, 1033.62 and 955.17 mg L-1, respectively. It also revealed the concentration- and time-dependent increased mortality rate under these toxicants. The safety concentrations (SC) of As, Cr and Almix to tadpoles were 3.26, 14.20 and 95.52 mg L-1, respectively. The findings disclosed that As is highly toxic to E. cyanophlyctis than Cr and Almix. Alkaline phosphatase (ALP) activity showed varied responses to exposed chemicals. In particularly, ALP activity reduced significantly for Cr treatment. Glutathione S-transferase (GST) activity in E. cyanophlyctis was significantly inhibited by As treatment (p < 0.05); however, GST activity was remain unchanged for Cr and Almix (p > 0.05). The As toxicity correlates positively with GST inhibition (r = 0.779, p < 0.01); contrarily, Cr and Almix revealed negative correlation with GST induction (r = -0.461 and -0.19, respectively; p > 0.05). This result indicated that GST play a crucial role for regulating the tadpole mortality and intoxication by As, Cr and Almix. Overall, our findings demonstrate the different levels of toxic sensitivity (adverse effects) under different toxicants on E. cyanophlyctis tadpoles. Finally, the present findings could be used as baseline information of toxicosis for metalloid, heavy metal and herbicide exposures in wild frog populations.

中文翻译：

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氰化蓝Eu中砷，铬和混合20WP的急性毒性评估。

由于重金属和除草剂对水生生物特别是两栖动物具有不利影响，因此在水生毒理学方面正受到严重的环境关注。因此，本研究首次评估了两种重金属[砷（As3 +）和铬（Cr6 +）]和除草剂（Almix）对印度ski蛙frog（Euphlyctis cyanophlyctis）的急性毒性。As，Cr和Almix在24、48、72和96小时内的LC50值为73.58、56.31、43.58和32.58 mg L-1；326.68、224.31、171.92和141.99 mg L-1；分别为1297.85、1148.22、1033.62和955.17 mg L-1。它还揭示了在这些有毒物质下浓度和时间依赖性的死亡率增加。As，Cr和Almix对t的安全浓度（SC）分别为3.26、14.20和95.52 mg L-1。研究结果表明，As对E有剧毒。蓝藻比Cr和Almix。碱性磷酸酶（ALP）的活性显示出对暴露的化学物质的不同反应。特别地，对于Cr处理，ALP活性显着降低。砷处理显着抑制了蓝藻大肠杆菌中的谷胱甘肽S-转移酶（GST）活性（p <0.05）。但是，Cr和Almix的GST活性保持不变（p> 0.05）。As毒性与GST抑制呈正相关（r = 0.779，p <0.01）; 相反，Cr和Almix与GST诱导呈负相关（r分别为-0.461和-0.19； p> 0.05）。该结果表明，GST在调节As的死亡和砷，铬和铝混合物的中毒方面起着至关重要的作用。总体而言，我们的发现表明，在E上不同的毒物作用下，其不同的毒性敏感性水平（不良反应）。蓝藻t。最后，本研究结果可以用作野生蛙种群中类金属，重金属和除草剂暴露中毒的基线信息。