Heavy bioaccumulative metals in Tilapia (oreochromis niloticus) in the bed of the Balsas river, Tierra Caliente de Guerrero

Abstract

Heavy metals affect the food chain due to its bioaccumulation; this is due to its high persistence in the environment. The study of the content of metals in food is an important aspect because some of these metals are necessary for the normal development of organisms, while others, even at low concentrations can not be tolerated due to their toxicity to humans. The objective of the present study is to record the concentration of heavy metals in Orechromis niloticus (tilapia). In September 2017, 85 specimens were collected, frozen in situ and transported to the laboratory for analysis. The samples were analyzed by atomic absorption spectrophotometry. The results indicate the presence of Pb in fish, in the muscle a concentration was registered above the permissible limits. The presence of Cr, Cd and Mn in the gills was recorded in relatively high concentrations (Golovanova, 2008). Therefore, it is important to monitor these elements to guarantee the quality of the fish that comes from this river in the Balsas channel. The dangers of metals to humans from the consumption of contaminated food will depend on the relative levels of metal and its speciation. In case of chronic toxicity, it is known that lead causes harmful effects on the kidneys; in addition to the deterioration of renal function, hepatic dysfunction and poor reproductive capacity (Abou-Arab et al., 1996); It has also been reported that in humans, exposure to lead produces a reduction in the intellectual coefficient, learning difficulties, growth retardation, behavioral abnormalities, hearing difficulties and cognitive functions (Dahiya et al., 2005).