Toxic elements in contact with the human body cause numerous health problems. The contamination occurs mostly by food consumption, such as the ingestion of fish contaminated with high concentrati ons of As, Cd, Hg or Pb among other elements. Many fishermen and their family members end up exposing themselves to different toxic elements due to fish based diet as the main protein nutrient because they are unaware of the health risks associated with th e consumption of fish from contaminated waters. In the present study, quantification of the toxic or potentially toxic elements As, Br, Cs, Cr, Co, Fe, K, Na, Sc, Se and Zn in samples of fish of the genus Astyanax (known by the common name of lambari )). The fish was collected at Billings Reservoir by fishermen from the Riacho Grande District (S??o Bernardo do Campo city , S??o Paulo State, Brazil ) is presented. The lambari fish had great relevance in this study because it is consumed as a snack, in which the subject feeds on the whole organism of the fish, having a greater risk of direct contact with toxic elements through ingestion. Elements were determined by Instrumental Neutron Activation Analysis (INAA). This study is important in establishing an updated spatiotemporal vision of the contamination by various elements of interest in the region Additionally, it contributes to the food safety assurance, regarding inorganic contaminants referred by the Brazilian Health Regulatory Agency (ANVISA).