Evaluation of the Bioavailability of Heavy Metals by Saline, EDTA and HCL Solutions in Agricultural Soil

Abstract

The objectives of this study is to determine the bioavailability of eight heavy metals (Cu, Cd, Pb, Mn, Co, Ni, Cr and Fe) by the different extractants (complexing agent EDTA and saline solutions: NH4OAC, NaNO3, CaCl2 and NH4NO3, acid HCl) in an agricultural soil on the one hand and on the other hand in the different organs of a food plant (durum wheat) of the city of Hammam Boughrara-Algeria and this in order to evaluate the rate of contamination of these heavy metals. It turned out that the part extracted is not very representative of the fraction actually bioavailable in agricultural soil and in the food plant, durum wheat. As for the cultivated plant, the study indicates a potential ecological risk of durum wheat contaminated particularly by chromium, to a lesser extent by cadmium, lead and copper thus causing potential health risks, on the other hand manganese presents deficiencies in the soil and in the aerial parts. All the results obtained constitute a first step towards understanding the effects affecting the soils irrigated by wastewater, the waters of the Tafna River and the Hammam Boughrara dam. The first advantage of such an approach is that it provides a present state of the soil studied in the perimeter of Hammam Boughrara which can then be useful for monitoring the situation over the long term.