Department of Plant and Environmental Sciences, University of Gothenburg, Box 461, 405 30 Gothenburg, Sweden.
Environ Toxicol. 2011 Jun;26(3):315-24. doi: 10.1002/tox.20559.
An unexpectedly high frequency of skeletal deformations in brown trout has previously been observed in the brook Vallkärrabäcken in southern Sweden. Environmental pollutants from storm water and leachate from an old landfill have been suggested as responsible for the observed deformations. Biomarkers in farmed rainbow trout, placed in tanks with water supplied from the brook, were used to investigate if exposure to pollutants may induce toxic responses in fish. Furthermore, biomarkers were also measured in wild brown trout that were caught in the brook. The most important finding was that the hepatic ethoxyresorufin-O-deethylase (EROD) activity was five to seven times higher for rainbow trout and brown trout in exposed areas compared to reference sites (P<0.001). Analyses of bile in rainbow trout showed that the concentration of PAH-metabolites was two to three times higher (P<0.001) in the exposed areas. However, due to their smaller size and the feeding status, only insufficient amounts of bile could be retrieved from the wild brown trout. The study provides evidence for pollution in parts of Vallkärrabäcken. It is therefore possible that the previously observed high frequency of skeletal damage have been caused by pollutants. The methodology with farmed rainbow trout in flow through tanks worked well and provided more information about the occurrence of pollutants in Vallkärrabäcken than the data from brown trout. The main reasons for this were that the size and the feeding status of the fish could be controlled. This allowed a total of 21 biomarkers to be analyzed in farmed rainbow trout compared to only five in wild brown trout. Furthermore, the use of farmed fish eliminates the risk of migration, which may otherwise bias the data when wild fish are used.
先前在瑞典南部的 Vallkärrabäcken 小溪中观察到褐鳟骨骼畸形的频率异常高。有观点认为，来自雨水的环境污染物和旧垃圾场的渗滤液是导致观察到的畸形的原因。在装有来自小溪的水的水箱中放置养殖虹鳟的生物标志物，用于研究暴露于污染物是否会引起鱼类的毒性反应。此外，还在小溪中捕获的野生褐鳟中测量了生物标志物。最重要的发现是，暴露区虹鳟和褐鳟的肝乙氧基荧蒽-O-脱乙基酶（EROD）活性比参照点高 5 至 7 倍（P<0.001）。对虹鳟的胆汁分析表明，暴露区的多环芳烃代谢物浓度高 2 至 3 倍（P<0.001）。然而，由于它们的体型较小和摄食状态，只能从野生褐鳟中获得数量不足的胆汁。该研究为 Vallkärrabäcken 部分地区的污染提供了证据。因此，先前观察到的骨骼损伤高发率可能是由污染物引起的。用流动水箱中的养殖虹鳟进行的方法学研究效果很好，提供了比野生褐鳟数据更多关于 Vallkärrabäcken 污染物发生情况的信息。主要原因是可以控制鱼类的大小和摄食状态。这使得可以在养殖虹鳟中分析总共 21 种生物标志物，而在野生褐鳟中仅分析 5 种。此外，养殖鱼类的使用消除了因使用野生鱼类而可能导致数据偏倚的洄游风险。
