Evaluation of heavy metal concentrations in vegetable crop cultivation areas in Minas Gerais, Brazil

摘要

> size="2" face="Verdana">The objective of this study was to investigate the presence of heavy metals (Cd, Pb, Cu, Cr, Fe, Mn, Mo, Ni and Zn) in agricultural soils, irrigation waters and some vegetable crops in the State of Minas Gerais, Brazil. Samples were submitted to an acid digestion and the heavy metal contents were determined using an ICP-OES. The majority of soil samples presented low heavy metal content, and did not indicate accumulation of these elements in soil, with the exception of Cr and Cd, which presented contents justifying complementary analysis. However, for these elements, the DTPA extraction data were close to zero, indicating their low availability. In water samples the presence of Cd and Pb was not detected. Considering the maximum contents permitted by the Brazilian legislation, only a few samples were above the limits. In the vegetables samples, contents of Cd, Cr and Ni not even approached the critical limit, and the majority of the other elements barely exceeded the considered limit. In general, the data show that the soil, water and vegetables samples analyzed were not contaminated by heavy metals.