BIOCONCENTRACIÓN Y RIESGOS POR METALES EN PLANTAS CULTIVADAS Y RUDERALES COMESTIBLES DEL ESTADO VARGAS, VENEZUELA.

Human consumption of leafy vegetables is a common way to obtain nutrients. However, there are risks of contamination by metals and consequent health damage because conventional agricultural practice, based on high yields and short growing cycles, requires the use of agrochemicals. The objective of this study was to evaluate and compare the contents, bioconcentration and toxicity risks of nutrients and non-essential mineral elements in three leafy vegetable species: a crop species, coriander (Coriandrum sativum), and the ruderals amaranthus (Amaranthus hybridus) and wild basil (Galinsoga sp.), wild growing species with dietary potential. In an agricultural area of the Carayaca rural community in Vargas State, Venezuela, adult leaves of the three species were collected the first year and the two ruderals in the second year. Samples were dried, milled and digested in nitric and perchloric acids, and the concentration of mineral elements was measured by plasma spectrometry (ICP). Contents of Ca, Mg and P showed high nutritional potential in the ruderals. Nickel concentrations in A. hybridus (1.2 mg kg-1 - 6.7 mg kg-1) were above the permissible limits of FAO, whereas Mn, Cr, Cu and Zn were below those limits but significantly higher in ruderals than in coriander. The bioconcentration factors of Ca and P in ruderal species were greater than 1. The risk coefficients for Ni and Pb were high for all the species studied, which implies risk in hypothetical scenarios of high consumption by children. [ABSTRACT FROM AUTHOR]