Concentration and distribution of heavy metals in tissues of wild and farmed shrimp Penaeus vannamei from the northwest coast of Mexico

Abstract

The concentration and distribution of Fe, Mn, Ni, Cu, Cd, and Zn among the tissues of wild and farmed pre-adult shrimp Penaeus vannamei collected from the northwest coast of México was determined. Distinct inter-tissue and inter-site differences in metal concentrations were observed. In general, highest concentrations of Zn, Ni, and Cd were found in hepatopancreas while higher levels of Cu and Fe occurred in gills. The highest Mn concentrations were noted in the antennal organs and exoskeleton. Differences between shrimps were evident in the exoskeleton (for both sexes) and hepatic material (females). The farmed shrimp (larger in size) accumulated more Fe than the wild shrimp. Similarly, in the hard tissues (exoskeleton and antennal organs) the farmed shrimp accumulated more Cu than the wild shrimp for both sexes, while the wild shrimp accumulated more Mn than the farmed shrimp in the hard tissues of both sexes.