BIOACUMULAÇÃO DE MACRO E MICROELEMENTOS EM PLANTAÇÃO DE FEIJÃO (Vigna unguiculata L. WALP) E AVALIAÇÃO DO POTENCIAL RISCO AO CONSUMO HUMANO

Abstract

Beans are one of the most important leguminous for human consumption in the world and represents an important source of protein for the diet. Brazil is one of the largests consumers of beans in the world and one of the main producers of cowpea in South America. However, the accumulation of minerals in this food can pose a risk to the human food chain. Thus, predicting or measuring the likely risks arising from exposure to heavy metals from soil, water, atmospheric deposition and accumulation in different crops used as food, has become increasingly common and this risk assessment is analyzed together with the data of pollution indices, transfer and bioaccumulation factors, for a better understanding of the threats to human health. The aim of this study was to investigate the accumulation and transfer of macro and microelements from the soil to grains, leaves and pods of cowpea. And to evaluate the levels of soil pollution and the health risks associated with the consumption of the edible part of the crop. The quantification of minerals As, Cd, Cr, Cu, Fe, Mg, Mn, Mo, Pb, Se, V and Zn by ICP OES was carried out in grain, leaf, pod and soil samples from the cowpea crop, located in Campo Grande-MS and surrounded by a stream, landfill, vegetation and highway. With the data on the concentrations of macro and microelements, calculations of the pollution index, bioaccumulation coefficient, estimated intake, carcinogenic and non-carcinogenic risk were performed. The content of Cd and Pb in the grains was above the maximum daily oral dose. The risk quotients of the elements As, Cd, Pb, Se and V, were above the safety limit, the risk index was > 1 for all elements analyzed and based on the daily dose of chronic ingestion, the heavy metals As, Cd, Cr and Pb present carcinogenic risk. The proximity of the cowpea crop to the highway and the landfill contributed to the contamination of the soil and, consequently, of the cowpea grains. These findings show the importance of monitoring and understanding the soil-plant-human system, especially when the environmental conditions around the crops are favorable to contamination, representing a great risk to public health.