Trace elements detection in tissues of fish (Pseudoplatystoma coruscans) caught in the São Francisco river (MG)

Abstract

Surubim (Pseudoplatystoma coruscans) is a predator fish found in the São Francisco River in Minas Gerais state, and it isfrequently consumed by both the local population as well as people throughout the entire state. Despite the significant advantagesof having fish as part of a normal diet, one of the more recent concerns of state and federal governmental agencies is the metalcontamination in these catches. In this context, a study was conducted on the content of mercury, lead, cadmium, arsenic andzinc in 59 sample units of liver, spleen, kidney, and muscular tissue from surubim fish captured during different periods of theyear in the São Francisco River. The liver and kidney samples presented mercury, cadmium, zinc, and lead contamination atlevels above the limits set forth under Brazilian law. The spleen samples also presented cadmium, zinc, and lead contaminationat levels above the legal limit as well. However, in muscular tissue, no presence of the metals analyzed herein was detected atabove the legal limits. A positive and directly proportional correlation of 72% was found among metals studied. The positivecorrelation between of lead and cadmium concentrations in the spleen was 82%. It is important to note that, although these fishare appropriate for human consumption, the presence of metals in these fish samples should serve as a warning for the periodicinspection of the studied area, regarding not only human consumption but also the different biological systems in which all faunaand flora are present.