Potential Toxic Elements Accumulation in Several Food Species Grown in Urban and Rural Gardens Subjected to Different Conditions

Abstract

Urban agriculture increased in Seville (South Spain) in the last 20 years and play different roles in the urban context. Edible species can be contaminated by soil and airborne contamination leading to health risks. Samples of different crop and fruit species and their soils were collected in urban and rural gardens, including urban gardens from a mining area to investigate the potential contamination in food and soils. Results show that soils from mining gardens were the most contaminated. In the city, crops were generally not more contaminated those in the rural area. Most differences were observed between species, chard and lettuce were the species that reached the highest level of most elements’ accumulation and fruits always had lower metal accumulation than leafy vegetables. Arsenic, Cd, and Pb concentrations did not exceed the FAO/HWO and European legal maximum levels for vegetables studied, so their consumption would be safe for human health. The concentration of Cr, Cu, Mn, and Ni can be considered in the range cited in the bibliography. Special attention should be paid for leafy green vegetables (lettuce and chard) since high values of Ba and Zn were found, up to 42 and 123 mg kg−1, respectively, and the risk to human health associated with consuming these species should be studied.