Abstract:
During January 2013, a mining spill occurred in the Santa Maria mining region, releasing around 300,000 m3 of tailings on Los Remedios river, which was transported through the San Lorenzo river and finally to El Comedero (EC) dam. Twenty months later, we examined the concentrations of Hg and Se in the muscle, liver, gills, and guts of three fish species (Cyprinus carpio, Oreochromis aureus, Micropterus salmoides) captured in the EC dam to assess the performance of the cleaning operations. A high Se concentration in the liver of all species (carp, 1.2 ± 0.4; tilapia, 3.9 ± 2.1; bass, 3.5 ± 1.1 µg g-1 ww) was consistently observed, while this behavior was only found in the blue tilapia for Hg (0.15 ± 0.11 µg g-1 ww). Tilapia (benthic-detritivorous) exhibited the highest Se concentrations compared to the carp (omnivore) and the largemouth bass (piscivore). In contrast, the largemouth bass had the highest Hg levels in the muscle compared with the other fishes. Such differences could be related to the different metabolism and feeding habits among species. Compared to a tilapia study carried out three months after the mine spill during a mortality event, a decrease was evident in the liver for Se and Hg by 7.2 and 4.7 times, respectively. This reveals that cleaning operations were more efficient for Se and less for Hg, and that a prolonged period was required for the partial recovery of the element levels in fish from sites impacted by mining. Considering the Mexican consumption scenarios for each fish species, it could be concluded that there will be no non-cancer risk by exposure to Hg or Se.
摘要:
2013年1月,圣玛丽亚矿区发生采矿泄漏,在LosRemedios河上释放约30万立方米的尾矿,通过SanLorenzo河运输,最后到达ElComedero(EC)大坝。20个月后,我们检查了肌肉中汞和硒的浓度,肝脏,ill,和三种鱼类的内脏(鲤鱼,金黄色葡萄球菌,Micropterussalmoides)在EC大坝中捕获,以评估清洁操作的性能。所有物种的肝脏中硒浓度都很高(鲤鱼,1.2±0.4;罗非鱼,3.9±2.1;低音,始终观察到3.5±1.1µg-1ww),而这种行为仅在蓝色罗非鱼中发现汞(0.15±0.11µg-1ww)。与鲤鱼(杂食动物)和大嘴鲈鱼(piscivore)相比,罗非鱼(底栖有害动物)的硒浓度最高。相比之下,与其他鱼类相比,大嘴鲈鱼肌肉中的汞含量最高。这种差异可能与物种之间的代谢和摄食习惯的不同有关。与死亡事件期间矿山泄漏三个月后进行的罗非鱼研究相比,肝脏中Se和Hg明显减少7.2和4.7倍,分别。这表明,清洁操作对Se更有效,对Hg更低,并且需要长时间才能从受采矿影响的地点部分恢复鱼类中的元素水平。考虑到墨西哥对每种鱼类的消费情况,可以得出结论,暴露于Hg或Se不会有非癌风险。