LAUSR

ABSTRACT One of the current challenges of soil research is how to assess quality simply and reliably. Trace contaminant metals and As in soils were determined in order to assess the toxicity effects on plants and the impact on the environment and human health in general. This work aimed to apply a simple microwave-assisted digestion procedure based on USEPA 3051 for soil samples used for cocoa cultivation, and the determination of extracted metals and As by inductively coupled plasma mass spectrometry. Furthermore, based on the concentrations determined, the effects of anthropogenic processes on soils collected either from impacted areas or from areas with limited impact were evaluated by applying artificial neural networks. The analytes studied were As, Cd, Co, Cr, Cu, Ni and Pb. Accuracy was evaluated by analysing a certified reference material and by performing addition and recovery experiments. It was concluded that the analytical procedure was suitable in terms of accuracy and sensitivity. Considering the data, it can be inferred that anthropogenic processes affected the studied soils and caused an elevation in metal concentrations that may eventually cause toxic effects; therefore, additional studies are needed for a broader evaluation of the quality of soil used for cocoa cultivation in the southern region of Bahia.