Investigations on the relationship between extracting (DTPA) solutions and plant (Phaseolus vulgaris) in the uptake of cadmium and lead from latosols

Abstract

Given the relationship between the contents of heavy metals extracted from contaminated soil samples and dilution of these samples in diethylenetriaminepentacetic acid (DTPA) solution, the goal of this work was to test three soil–extractant solution ratios, namely 1:5, 1:10, and 1:15. The extracted contents from each solution were compared to those extracted by bean plants (Phaseolus vulgaris) cultivated in a greenhouse in two different soils: dystrophic red latosol (RLd) and humic red-yellow latosol (RYLh). Contents of cadmium (Cd) and lead (Pb) were greater in RYLh (lower amount of clay) for all soil–extractant ratios; 1:5 and 1:10 ratios differed negligibly from the plant result for the Cd extraction, while for Pb, the 1:15 soil–extractant ratio was the one that better correlated with the extractive behavior of sensitive indicator plants.