Rigaud Cyril, Härme Julia, Vehniäinen Eeva-Riikka
Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland.
Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland.
Comp Biochem Physiol C Toxicol Pharmacol. 2022 Feb;252:109219. doi: 10.1016/j.cbpc.2021.109219. Epub 2021 Oct 29.
Salmonids are known to be among the most sensitive fish to dioxin-like compounds (DLCs), but very little is known about the sensitivity of the brown trout (Salmo trutta), which has declined and is endangered in several countries of Europe and Western Asia. We investigated the sensitivity of brown trout larvae to a widespread dioxin-like PAH, retene (3.2 to 320 μg.L), compared to the larvae of a salmonid commonly used in toxicology studies, the rainbow trout (Oncorhynchus mykiss). Mortality, growth, cyp1a induction and the occurrence of deformities were measured after 15 days of exposure. Brown trout larvae showed a significantly higher mortality at 320 μg.L compared to rainbow trout larvae. While the occurrence of deformities was only significantly increased at 320 μg.L for the rainbow trout, brown trout larvae displayed pericardial edemas and hemorrhages already at 10 or 100 μg.L. cyp1a induction was increased significantly already at ≥3.2 μg.L for the brown trout, versus ≥32 μg.L for the rainbow trout. Least square regression analysis of the concentration-response relationships suggested that S. trutta larvae were at least 2 times more sensitive than O. mykiss larvae for cyp1a induction. The present study suggests that S. trutta larvae are more sensitive than O. mykiss larvae to a potent DLC, retene. As it is possible that S. trutta populations have declined partly because of pollution by DLCs, we recommend generating more data regarding the sensitivity of threatened fish populations, in order to ensure better risk assessment.
已知鲑科鱼类是对二噁英类化合物（DLCs）最敏感的鱼类之一，但对于褐鳟（Salmo trutta）的敏感性却知之甚少。褐鳟数量在欧洲和西亚的几个国家已经减少且濒临灭绝。我们研究了褐鳟幼鱼对一种广泛存在的二噁英类多环芳烃——惹烯（浓度为3.2至320μg.L）的敏感性，并与毒理学研究中常用的鲑科鱼类虹鳟（Oncorhynchus mykiss）幼鱼进行了比较。在暴露15天后，测量了死亡率、生长情况、cyp1a诱导以及畸形的发生情况。与虹鳟幼鱼相比，褐鳟幼鱼在320μg.L时死亡率显著更高。虽然虹鳟仅在320μg.L时畸形发生率才显著增加，但褐鳟幼鱼在10或100μg.L时就已出现心包水肿和出血。对于褐鳟，cyp1a诱导在≥3.2μg.L时就已显著增加，而虹鳟则在≥32μg.L时才显著增加。浓度 - 反应关系的最小二乘回归分析表明，在cyp1a诱导方面，褐鳟幼鱼比虹鳟幼鱼至少敏感2倍。本研究表明，褐鳟幼鱼对一种强效DLC——惹烯比虹鳟幼鱼更敏感。由于褐鳟种群数量下降部分可能是由于DLCs污染所致，我们建议生成更多关于受威胁鱼类种群敏感性的数据，以确保更好的风险评估。
