The wastewater contamination of urban rivers is a concern for biodiversity and a consequence from poor urban conservation policies. In the current study, the impact of urban and industrial activities was investigated in Iguaçu river (Southern Brazil) using juvenile Oreochromis niloticus, after trophic and chronic exposure (25, 50 and 100 %), over 81 days. After exposure liver, gills, gonads, brain, muscle, and blood were sampled for chemical, biochemical, histopathological, genotoxic and molecular analyses. Water levels of persistent organic pollutants such as polychlorinated biphenyls, organochlorine pesticides, polycyclic aromatics hydrocarbon (PAHs) and metals were investigated. The redox unbalance, histopathological and increase in vitellogenin expression in fish revealed both the bioavailability of micropollutants and their harmful effects. According to the results, the level of Iguaçu river pollution negatively impacts the health of O. niloticus revealing and highlighting the risk of this pollution exposure to biota and human populations.

城市河流的废水污染是对生物多样性的关注，也是城市保护政策不力的结果。在当前的研究中，使用少年Oreochromis niloticus对伊瓜苏河（巴西南部）的城市和工业活动的影响进行了调查，营养和慢性暴露（分别为25％，50％和100％）后81天。暴露后，对liver，性腺，大脑，肌肉和血液进行采样，以进行化学，生化，组织病理学，遗传毒性和分子分析。调查了持久性有机污染物（如多氯联苯，有机氯农药，多环芳烃和金属）的水位。鱼类中的氧化还原失衡，组织病理学和卵黄蛋白原表达的增加揭示了微污染物的生物利用度及其有害作用。根据结果​​，伊瓜苏河的污染水平对尼罗罗非鱼的健康产生了负面影响，这揭示并强调了这种污染暴露于生物群和人类的风险。