Extractors for barium,cadmium, copper,nickel, and zinc in tropical soils

ABSTRACT

The accumulation of potentially toxic elements (PTEs) in the soil can pose risks to human health, and precise risk assessment dealing with the production and consumption of plants is required. The 0.43 M of nitric acid (HNO?) solution was suggested by the International Organization for Standardization for reactive fraction of PTEs in the soil. The efficiency of some extractors was evaluated in tropical soils. Contents of barium (Ba), cadmium (Cd), copper (Cu), nickel (Ni) and zinc (Zn) were extracted in accordance with the methods of Environmental Protection Agency (EPA) 3051A, Aqua Regia, Diethylenetriaminepentaacetic acid (DTPA), Mehlich-1, Mehlich-3, 0.43 M HNO? and 0.01 M of calcium chloride (CaCl?), and these contents correlated with the contents of PTEs in roots, shoots, and fruits of vegetables. Mehlich-3 had the highest correlation with Ni and Zn contents extracted by the plants. Contents extracted with 0.43 M HNO? had high correlation with the amounts extracted by DTPA and Mehlich-3, as well as with the amounts of PTEs accumulated by plants.