Globally, amphibians are experiencing widespread abnormalities and population declines. One potential contributor to these challenges is the use of pesticides, particularly aquatic herbicides applied to aquatic habitats inhabited by amphibians. Critical issues of concern are the potential toxicity and teratogenicity of these herbicides towards amphibians. Using the FETAX protocol, three globally used formulations, including diquat dibromide (Midstream), glufosinate ammonium (Basta), and imazapyr (Arsenal), were assessed for embryotoxicity, teratogenicity, and growth inhibition. Developing Xenopus laevis embryos were exposed for 96 h at concentrations of 0.5–3.0 mg/L, 1.6–3.0 mg/L, and 20–45 mg/L for Midstream, Basta, and Arsenal respectively. The 96-h LC₅₀ estimates were 0.83 mg/L acid equivalent (a.e.), 36 mg/L a.e., and 2.2 mg/L a.e., whereas the EC₅₀ estimates were 0.24 mg/L a.e., 28.13 mg/L a.e., and 2.01 mg/L a.e. for the Midstream, Arsenal, and Basta formulations, respectively. These two estimates produced Teratogenic Index of 3.5, 1.3, and 1.1 for Midstream, Arsenal, and Basta, respectively, indicating a high risk of malformation induction by Midstream and moderate risk for Arsenal. Regarding growth inhibition, lowest observable effect concentrations of 0.5 mg/L, 25 mg/L, and 2.0 mg/L were computed for Midstream, Arsenal, and Basta, respectively, producing the minimum concentration inhibiting growth (MCIG) ratios of 0.62, 0.69, and 0.89 for the three formulations. These MICG values are higher than the standard 0.30 growth inhibitors benchmark, suggesting that the formulations are not growth inhibitors at the evaluated concentrations. This study provides evidence of the embryotoxic and teratogenic status of Midstream and the embryotoxicity of Basta. There is a need to further characterise the physiological and ecological impacts of these formulations to ensure responsible use and the safety of amphibians and other wildlife.

在全球范围内，两栖动物正经历着广泛的异常和人口下降。应对这些挑战的潜在原因之一是使用农药，特别是将水生除草剂应用于两栖动物栖息的水生生境。关注的关键问题是这些除草剂对两栖动物的潜在毒性和致畸性。使用FETAX协议，评估了三种全球使用的制剂，包括敌草快二溴化物（Midstream），草铵膦铵盐（Basta）和依马吡吡（Arsenal）的胚胎毒性，致畸性和生长抑制作用。发育中的非洲爪蟾胚胎在中游，巴斯塔和阿森纳的浓度分别为0.5-3.0 mg / L，1.6-3.0 mg / L和20-45 mg / L暴露96 h。96小时LC ₅₀估计分别为0.83 mg / L酸当量（ae），36 mg / L ae和2.2 mg / L ae，而EC ₅₀对于中游配方，阿森纳配方和Basta配方，估计分别为0.24 mg / L ae，28.13 mg / L ae和2.01 mg / L ae。这两个估计分别导致中游，阿森纳和巴斯塔的致畸指数分别为3.5、1.3和1.1，这表明中游引起畸形的风险很高，而阿森纳则为中等风险。关于生长抑制，分别计算了中游，阿森纳和巴斯塔的最低可观察效应浓度为0.5 mg / L，25 mg / L和2.0 mg / L，产生的最小抑菌生长（MCIG）比率为0.62、0.69。 ，对于这三种公式，则为0.89。这些MICG值高于标准的0.30生长抑制剂基准，表明该制剂在所评估的浓度下不是生长抑制剂。这项研究提供了中游的胚胎毒性和致畸状态以及Basta的胚胎毒性的证据。需要进一步表征这些制剂的生理和生态影响，以确保负责任的使用以及两栖动物和其他野生动植物的安全。