Content, bioavailability and sources of metals and semi-metals in soils and vegetables of community gardens in Bratislava

This study examines the soil and vegetables of community gardens in Bratislava using geochemical and statistical tools, with an emphasis on the content and origin of potentially risky elements. Another important goal is to determine the potential health risks associated with working in community gardens and consuming grown products. Increased concentrations of Cu, Pb, Sb and Zn were recorded in the soils of community gardens in Bratislava, while the content of metals and semi-metals in vegetables was generally low. Enrichment factor and principal component analysis indicate the natural origin of As, Co, Cr, Fe, Mn, Ni and V, and the anthropogenic origin of Cu, Pb, Sb and Zn. The investigated elements had a higher rate of bioavailability from plants than from soil, while the bioavailability of metals had a general decreasing trend from the gastric to the intestinal phase. The measured values of the ²⁰⁶Pb/²⁰⁷Pb isotopic ratios indicate a mixed origin of Pb in the soils, and a preferential accumulation of anthropogenic Pb from the soil to cultivated vegetables. From the point of view of potential health risks from exposure to metals and semi-metals in soil and vegetables, it can be assessed that physical work in community gardens and consumption of grown products do not pose health risks. (authors)