Taylor Vivien F, Buckman Kate L, Chen Celia Y, Kraft Jana
Department of Earth Sciences, Dartmouth College, Hanover, NH 03755, United States of America.
Connecticut River Conservancy, Greenfield, MA 01301, United States of America.
Sci Total Environ. 2025 Jul 15;986:179786. doi: 10.1016/j.scitotenv.2025.179786. Epub 2025 May 29.
Commercial marine fish are a major source of exposure to harmful compounds such as methylmercury (MeHg) but are also an important source of nutrients including selenium (Se) and omega-3 polyunsaturated fatty acids (ω-3). Safe eating guidelines seek to provide information to minimize the risk of contaminant exposure, while promoting the nutritional benefits of eating fish, yet information on the patterns and drivers of contaminants and nutrients are scarce, particularly within and across populations of commercially harvested marine fish species. This study assessed total mercury (Hg), Se and total lipids, along with subsets of MeHg and ω-3, in muscle tissue of six species of fish (Atlantic cod, Atlantic herring, red hake, silver hake, little skates and spiny dogfish) caught in the Gulf of Maine, the largest coastal fishery in the U.S. Fish species, as well as size and catch location (inshore vs. offshore) had a significant effect on concentrations of Hg and lipids, whereas Se concentrations varied little, except in skate. Higher length-adjusted concentrations of Hg and lower concentrations of lipids were found inshore for Atlantic cod, whereas the reverse was true for Atlantic herring, and Hg was also higher in offshore spiny dogfish. Stable isotope analysis and differences in catch timing suggest these patterns are due to seasonal and locational differences in plankton community compositions and in prey availability to pelagic and demersal fish. These findings reveal that local environment plays an important role in determining both nutrient and contaminant load, and points to the effects of environmental change on the risk-inducing and beneficial qualities of commercially caught fish.
商业海洋鱼类是人们接触甲基汞（MeHg）等有害化合物的主要来源，但也是包括硒（Se）和ω-3多不饱和脂肪酸（ω-3）在内的重要营养来源。安全饮食指南旨在提供信息，以尽量减少污染物暴露风险，同时促进食用鱼类的营养益处，然而，关于污染物和营养物质的模式及驱动因素的信息却很匮乏，尤其是在商业捕捞的海洋鱼类种群内部及不同种群之间。本研究评估了在美国最大的沿海渔场缅因湾捕获的六种鱼类（大西洋鳕鱼、大西洋鲱鱼、红无须鳕、银无须鳕、小鳐和白斑角鲨）肌肉组织中的总汞（Hg）、硒和总脂质，以及甲基汞和ω-3的子集。鱼类种类以及鱼的大小和捕捞地点（近海与远海）对汞和脂质的浓度有显著影响，而硒浓度变化不大，鳐鱼除外。对于大西洋鳕鱼，在近海发现其汞的长度校正浓度较高而脂质浓度较低，而大西洋鲱鱼则相反，远海的白斑角鲨汞含量也较高。稳定同位素分析和捕捞时间的差异表明，这些模式是由于浮游生物群落组成以及中上层和底层鱼类的猎物可获得性存在季节性和位置差异所致。这些发现表明，当地环境在决定营养物质和污染物负荷方面起着重要作用，并指出了环境变化对商业捕捞鱼类的风险诱导和有益特性的影响。
