Many international guidance documents for deriving water quality guideline values recommend the use of chronic toxicity data. For the tropical fish northern trout gudgeon, Mogurnda mogurnda, 96-h acute and 28-d chronic toxicity tests have been developed, but both tests have drawbacks. The 96-h toxicity test is acute and has a lethal endpoint; hence it is not a preferred method for guideline value derivation. The 28-d method has a sublethal (growth) endpoint, but is highly resource intensive and is high risk in terms of not meeting quality control criteria. The present study aimed to determine the feasibility of a 7-d larval growth toxicity test as an alternative to the 96-h survival and 28-d growth tests. Once the method was successfully developed, derived toxicity estimates for uranium, magnesium, and manganese were compared with those for other endpoints and tests lengths within the literature. As a final validation of the 7-d method, the sensitivity of the 7-d growth endpoint was compared with those of 14-, 21-, and 28-d exposures. Fish growth rate, based on length, over 7 d was significantly more sensitive compared with existing acute toxicity endpoints for magnesium and manganese, and was similarly sensitive to existing chronic toxicity endpoints for uranium. For uranium, the sensitivity of the growth endpoint over the 4 exposure periods was similar, suggesting that 7 d as an exposure duration is sufficient to provide an indication of longer term chronic growth effects. The sensitivity of the 7-d method, across the 3 metals tested, highlights the benefit of utilizing the highly reliable short-term 7-d chronic toxicity test method in future toxicity testing using M. mogurnda. Environ Toxicol Chem 2021;40:1596–1605. © 2021 Commonwealth of Australia. Environmental Toxicology and Chemistry © 2021 SETAC.

中文翻译：

---

北方鳟鱼 Gudgeon、Mogurnda mogurnda 亚致死慢性毒性试验的开发以及对铀、镁和锰的应用

许多用于推导水质准则值的国际指导文件都推荐使用慢性毒性数据。对于热带鱼北部鳟鱼 gudgeon，Mogurnda mogurnda, 96 小时急性和 28 天慢性毒性试验已经开发出来，但两种试验都有缺点。96 小时毒性试验是急性的，具有致命的终点；因此，它不是准则值推导的首选方法。28 天方法具有亚致死（生长）终点，但资源高度密集，不符合质量控制标准的风险很高。本研究旨在确定 7 天幼虫生长毒性试验替代 96 小时存活和 28 天生长试验的可行性。一旦成功开发了该方法，将得出的铀、镁和锰毒性估计值与文献中其他终点和测试长度的估计值进行比较。作为 7-d 方法的最终验证，将 7-d 生长终点的敏感性与 14-、21-、和 28 天曝光。与现有的镁和锰急性毒性终点相比，7 天以上的鱼类生长速率（基于长度）明显更敏感，并且对铀的现有慢性毒性终点同样敏感。对于铀，4 个暴露期的生长终点的敏感性相似，这表明 7 天的暴露持续时间足以提供长期慢性生长效应的指示。7-d 方法在 3 种金属测试中的敏感性突出了在未来毒性测试中使用高度可靠的短期 7-d 慢性毒性测试方法的好处 并且对铀的现有慢性毒性终点同样敏感。对于铀，4 个暴露期的生长终点的敏感性相似，这表明 7 天的暴露持续时间足以提供长期慢性生长效应的指示。7-d 方法在 3 种金属测试中的敏感性突出了在未来毒性测试中使用高度可靠的短期 7-d 慢性毒性测试方法的好处 并且对铀的现有慢性毒性终点同样敏感。对于铀，4 个暴露期的生长终点的敏感性相似，这表明 7 天的暴露持续时间足以提供长期慢性生长效应的指示。7-d 方法在 3 种金属测试中的敏感性突出了在未来毒性测试中使用高度可靠的短期 7-d 慢性毒性测试方法的好处M. mogurnda。环境毒物化学2021；40:1596–1605。© 2021 澳大利亚联邦。环境毒理学和化学© 2021 SETAC。