Great Lakes Science Center, US Geological Survey, Ann Arbor, MI 48105, USA.
Arch Environ Contam Toxicol. 2012 Aug;63(2):262-9. doi: 10.1007/s00244-012-9767-2. Epub 2012 May 3.
Based on a laboratory experiment, we estimated the net trophic transfer efficiency of methylmercury to lake trout Salvelinus namaycush from its prey to be equal to 76.6 %. Under the assumption that gross trophic transfer efficiency of methylmercury to lake trout from its prey was equal to 80 %, we estimated that the rate at which lake trout eliminated methylmercury was 0.000244 day(-1). Our laboratory estimate of methylmercury elimination rate was 5.5 times lower than the value predicted by a published regression equation developed from estimates of methylmercury elimination rates for fish available from the literature. Thus, our results, in conjunction with other recent findings, suggested that methylmercury elimination rates for fish have been overestimated in previous studies. In addition, based on our laboratory experiment, we estimated that the net trophic transfer efficiency of inorganic mercury to lake trout from its prey was 63.5 %. The lower net trophic transfer efficiency for inorganic mercury compared with that for methylmercury was partly attributable to the greater elimination rate for inorganic mercury. We also found that the efficiency with which lake trout retained either methylmercury or inorganic mercury from their food did not appear to be significantly affected by the degree of their swimming activity.
基于实验室实验，我们估计甲基汞从其猎物向湖鳟（Salvelinus namaycush）的净营养传递效率等于 76.6%。假设甲基汞从其猎物向湖鳟的总营养传递效率等于 80%，我们估计湖鳟消除甲基汞的速度为 0.000244 天(-1)。我们实验室对甲基汞消除率的估计比从文献中可获得的鱼类甲基汞消除率的已发表回归方程预测的值低 5.5 倍。因此，我们的结果与其他最近的发现表明，在以前的研究中，鱼类对甲基汞的消除率被高估了。此外，基于我们的实验室实验，我们估计无机汞从其猎物向湖鳟的净营养传递效率为 63.5%。与甲基汞相比，无机汞的净营养传递效率较低部分归因于无机汞的消除率较高。我们还发现，湖鳟从食物中保留甲基汞或无机汞的效率似乎不受其游泳活动程度的显著影响。
