The expansion of urban centers, the increase in the use of chemicals in agriculture, and the significant expansion of industry has dumped increasing amounts of heavy metals into aquatic ecosystems, directly and indirectly affecting the entire food web in freshwater environments. In freshwater fish, many studies conducted worldwide have shown that these pollutants can cause alterations from the molecular level to behavioral, in all stages of life, including in future generations. Despite the great diversity of freshwater fish in the Neotropical region, few studies addressing the influence of metals on native species have been carried out. The last decade of studies showed that the effects of metals in neotropical species can be from the molecular to the behavioral level. Metals like Arsenic, Cadmium, Copper, Lead, Mercury, Chromium and Zinc have often been detected in environmental studies and evaluated in experimental approaches. Metabolically active organs showed higher levels of accumulation. In addition, some environmental studies have shown that ecologic and trophic conditions can be determinant in the level of exposure to metals. Oxidative stress, genotoxicity and several histopathological alterations were the most recurrent effects detected in target organs.

城市中心的扩张、农业中化学品使用的增加以及工业的显着扩张已将越来越多的重金属倾倒到水生生态系统中，直接或间接地影响了淡水环境中的整个食物网。在淡水鱼中，世界范围内进行的许多研究表明，这些污染物会在生命的所有阶段（包括后代）引起从分子水平到行为的改变。尽管新热带地区的淡水鱼种类繁多，但很少有研究解决金属对本地物种的影响。过去十年的研究表明，金属对新热带物种的影响可以从分子水平到行为水平。砷、镉、铜、铅、汞等金属，铬和锌经常在环境研究中被检测到，并在实验方法中进行评估。代谢活跃的器官显示出更高水平的积累。此外，一些环境研究表明，生态和营养条件可以决定接触金属的水平。氧化应激、基因毒性和一些组织病理学改变是在靶器官中检测到的最常见的影响。