Groupe de Recherche Interuniversitaire en Limnologie (GRIL), Université de Montréal, Département de Sciences Biologiques, Complexe des Sciences, C.P., 6128, Succ. Centre-Ville, Montréal, Québec, H3C 3J7, Canada.
Groupe de Recherche Interuniversitaire en Limnologie (GRIL), Département des Sciences Biologiques, Université Du Québec à Montréal (UQAM), 141 Avenue Du Président-Kennedy, Montreal, H2X1Y4, Canada.
Chemosphere. 2021 Feb;265:129036. doi: 10.1016/j.chemosphere.2020.129036. Epub 2020 Nov 19.
Current guidelines tend to limit fish consumption based on mercury (Hg) or monomethylmercury (MeHg) content in fish flesh, without considering the presence of antagonist chemical elements that could modulate Hg toxicity. However, it is difficult to assess the potential for antagonistic interactions of these elements since their covariation within muscle tissues is poorly known. Here we present the first study simultaneously mapping multiple metal(oid)s (Hg, As and Se), lipids and proteins in fish fillets in order to assess the magnitude of intra-organ variability of metals and the potential for antagonistic interactions. We mapped two fish species (Striped Bass and Northern Pike) with contrasting muscular structure with respect to the presence of white, intermediate and red muscles. In individual Striped Bass muscle tissues, metals varied on average by 2.2-fold. Methylmercury and selenium covaried strongly and were related to protein content as assessed by % N; arsenic was inversely related to these elements and was associated with the lipid fraction of the muscle. In Pike, no such relationship was found because the contents in proteins and lipids were less variable. Arsenic speciation revealed that arsenobetaine and arsenolipids were the only As species in those fish species, whereas the toxic inorganic As species (As) was under the detection limit. Arsenobetaine was related to % N, whereas arsenolipids covaried with % lipids. Elemental associations found with muscle lipids and proteins could help explain changes in bioaccumulation patterns within and between individuals with potential implications on fish toxicology, biomonitoring and human consumption guidelines.
目前的指南往往基于鱼肉中的汞（Hg）或甲基汞（MeHg）含量来限制鱼类的消费，而不考虑可能调节汞毒性的拮抗化学元素的存在。然而，由于肌肉组织中这些元素的共变关系知之甚少，因此很难评估这些元素的拮抗相互作用的潜力。在这里，我们首次进行了同时绘制鱼肉中多种金属（汞、砷和硒）、脂质和蛋白质的研究，以评估金属在器官内的变异性及其拮抗相互作用的潜力。我们绘制了两种肌肉结构存在差异的鱼类（条纹鲈鱼和北方狗鱼）的图谱，这两种鱼类具有白色、中间和红色肌肉。在单个条纹鲈鱼肌肉组织中，金属的平均变化幅度为 2.2 倍。甲基汞和硒强烈相关，与用 N%评估的蛋白质含量有关；砷与这些元素呈负相关，与肌肉的脂质部分有关。在狗鱼中，由于蛋白质和脂质的含量变化较小，因此没有发现这种关系。砷形态分析表明，在这些鱼类中，砷甜菜碱和砷脂是唯一的砷物种，而有毒的无机砷物种（As）低于检测限。砷甜菜碱与 N%有关，而砷脂与脂质含量有关。与肌肉脂质和蛋白质相关的元素关联可以帮助解释个体内和个体间生物累积模式的变化，这可能对鱼类毒理学、生物监测和人类消费指南产生影响。
