HEAVY METALS PROMOTE LIVER AND GILL OXIDATIVE STRESS AND HISTOPATHOLOGIES IN CICHLID FISHES: PROTOCOL FOR SYSTEMATIC REVIEW

Billions of tons of heavy metals are emitted every year by industrial chimneys and sewage, contaminating the hydrosphere and polluting rivers, lakes and seas. In this context, freshwater fish are the most affected due to their proximity to the source of contamination and are therefore used as bioindicators in the assessment of environmental impact after exposure to metals. However, our understanding of the effects of heavy metals on the detoxification organs – such as the liver and gills – of freshwater fish under environmental conditions is still limited. Thus, the aim of this review will be to determine the main cellular changes and mechanisms involved in the morphological modifications in the liver and gills of cichlid fish after exposure to heavy metals.