Estudo sobre a presença de metais em diferentes tecidos de peixes surubins (Pseudoplatystoma coruscans) capturados no Rio São Francisco (MG)

Abstract

Pseudoplatystoma coruscans is fish specie that inhabits an important river (SãoFrancisco) in the southeast of Brazil (Minas Gerais State). This fish specie is popularlyknown by Surubim and it is often consumed due the high nutritional value. In spite ofthe positive aspects of human consumption of fish, one of the concerns of the FederalDepartment is the metals contamination in fish. In Brazil, there is few data about thepresence the metals in fish, specifically in Surubim. This predator fish specie belongsto the higher level of aquatic ecosystem, and accumulates toxic residues, justifying theimportance of toxicological tests. The aim of this study was to detect mercury,cadmium, lead, zinc and arsenic levels in 59 liver, spleen, and kidneys samples and in20 skeletal muscle samples of captured Surubim at different seasons. The presenceof metals was evaluated by atomic absorption spectrophotometer. The liver andkidneys samples showed mercury, cadmium, zinc and lead, above the value allowedby the Brazilian legislation. The spleen samples, also presented contamination bycadmium, zinc and lead with values above the allowed by the Brazilian legislation. Inthe skeletal muscle, all values were below the tolerance limit allowed by the Brazilianlegislation. All fish that had bigger corporal mass had too bigger length, and it waspositive statistically proportional correlation. There was a positive correlation of 72%among metals studied. In spleen, there was a positive correlation of 82% between leadand cadmium. In this study, despite the fish skeletal muscles have metals levels belowthe permitted by Brazilian laws, the presence of metals must serve as an alert for aperiodic inspection of the area studied, not only for human consumption but for alldifferent biological systems