Research Article

Availability and Distribution of Arsenic in a Corn Crop in the Eastern Zone of the Province of Tucumán, Argentina

Abstract

There is a relationship between the arsenic content of crops and that of agricultural soils and the water used for irrigation. The consumption of foods with high arsenical concentrations represents a health risk. Corn is one of the most widely grown cereals in the world due to its ability to adapt to different soils and climates. In northern Argentina, the cultivation of this plant has become more important over the years. However, the groundwater supply of this zone has high arsenic levels. In this study, the levels and distribution of arsenic and its species in soils and corn plants of this agricultural area were determined. Some of the edaphic characteristics that facilitate its phytoavailability were also studied, and the rate of transfer and accumulation of the metalloid in the plant was determined. Elemental determinations were carried out by ICP-MS, FAAS and UV-VisS. Arsenical species were analyzed by HPLC-ICP-MS. We found that the soil is not contaminated with arsenic and that the proportion of the metalloid passing into the aqueous phase is low. However, a high proportion of this available arsenic is taken up by the plant. Although it was not detected in the cob kernels, the concentrations of arsenic in the roots and leaves of the plants are high, which represents a risk for its use as fodder. As(V) was dominant in the system. Methylated species were quantified in the plants even though they were not detected in the soil.