Metais pesados: prejuízos causados e répteis como bioindicadores de monitoramento

Abstract

A variety of metals are essential for animal health, as they are part of the body's physiological, structural and regulatory functions. However, while some metals in specific concentrations are necessary for cellular metabolism, others can be potentially toxic. Several elements circulate rapidly through trophic levels, accumulating in animal tissues that reach concentrations harmful to predators, including humans. Reptiles have interesting biological properties to monitor the quality of aquatic environments in urban areas, being considered good bioindicators. Therefore, the dissertation aimed to address the relationship of heavy metals with reptiles and determine Cadmium levels in populations of Trachemys dorbigni, in addition to exposing a set of promising cellular biomarkers to assess toxic effects at the cellular level in this species. Article 1 addresses a published review that investigated heavy metal exposure and the associated oxidative stress in reptiles, exploring topics about anthropic action, environmental bioindicators, free radicals and the antioxidant system. The review was concluded by validating the negative consequences of anthropic activities with damage to the ecosystem. In article 2, the research used T. dorbigni as a bioindicator of environmental pollution by cadmium. The hypothesis was that the animals reflected the damage caused by a potentially polluted aquatic environment. It was found that animals from urban areas are inserted in an aquatic biota contaminated by this metal and suffer from injuries at the cellular level, reflecting possible liver and muscle damage from chronic exposure to cadmium. This dissertation demonstrates the importance of environmental awareness to prevent and reduce future damage to the health of wild animals and humans.