Multiple potentially toxic elements in urban gardens from a Brazilian industrialized city

Abstract

Abstract Urban agriculture should be promoted as long as the food produced is safe for consumption. Located in the metropolitan region of São Paulo-Brazil, Santo André has intense industrial activities and more recently an increasing stimulus to urban gardening. One of the potential risks associated to this activity is the presence of potentially toxic elements (PTEs). In this study, the concentration of PTEs (As, Ba, Cd, Co, Cu, Cr, Ni, Mo, Pb, Sb, Se, V and Zn) was evaluated by soil (n=85) and soil amendments (n=19) in urban gardens from this municipality. Only barium was above regulatory limits in agricultural soil, although enrichment of all elements was observed. A multivariate statistical approach was applied and indicated two groups of elements with strong influence of the petrochemical complex located in this region. However, carcinogenic, and non-carcinogenic risks were not observed. Soil amendments were identified as a possible source of contamination for Ba, Zn and Pb and for pathogenic bacteria. Besides that, the occurrence of antimicrobial resistance suggests some soil management practices are necessary.