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In this study, leaves of the evergreen holm oak Quercus ilex were used to assess airborne contamination of potentially toxic elements (PTEs) at five towns located on the slopes of the Mt. Amiata (central Italy), an area with a long history of mining and, more recently, an important district for the industrial exploitation of geothermal energy. PTE composition and covariance of washed and unwashed Q. ilex leaves of three different ages (6, 12 and 24 month-old) were used to identify atmospheric inputs of PTEs at residential areas, evaluate long-term adsorption and retention of PTEs by the leaves, thus providing an indication of potential human exposure. Moreover, the determination of foliar concentrations of major elements (C, N, S and P) allowed an assessment of the nutritional status of the investigated urban tree stands which excluded the existence of stress condition caused by air pollution or other disturbances. Results indicated that overall Pb, Cu, and Cd concentration were low in the investigated urban sites, if compared with similar studies conducted in larger Italian cities, denoting a low contribution of vehicular traffic to the atmospheric pathway. The five urban settlements were characterized by a specific profile of elements (Al, Ba, Hg and Sb) enriched in unwashed leaves, resulting from the distinct geochemical characteristics of the area and from diffuse (i.e., urban activity) and point sources of PTEs emission (i.e., brownfields, geothermal power plants). The latter sources primarily govern the distribution of Hg, whose contamination was found to be very localized close to a major abandoned mining area. Our data provided quantitative evidence of the spectrum of PTEs potentially impacting resident population and may prove useful in support of follow-up instrumental monitoring campaigns of air quality, as well as for human health and ecological risk assessments. [ABSTRACT FROM AUTHOR]

BACKGROUND Cadmium (Cd) is a mobile heavy metal and soybeans accumulate more of this element compared to other grain crops. Because vegan and vegetarian lifestyles are increasingly popular, plant‐based diets should be free from contaminants. Cd minimization has recently been identified as a breeding aim in addition to protein and oil levels. It is also important to consider the regional variability of Cd in crops. RESULTS: A large sample collection (n = 602) was subjected to Cd analyses. Soybeans were grown using a standard protocol by private gardeners in a citizen science program. Some 12.5% of samples exceeded European Union limits, although Cd concentrations and exceedances showed regional variation around the national mean (0.13 mg kg−1). Contamination was higher in densely populated regions, possibly as a result of the long‐term emissions of heavy metal loaded dusts from industry, traffic and energy production. Cd concentrations were also elevated in regions once characterized by mining and heavy industry. Values were low overall in rural areas and agricultural regions despite potential inputs via phosphate fertilizers. CONCLUSION: Grain Cd levels are highly variable across Germany. Soybean farming may be problematic in regions with a long history of mining and heavy metal deposition. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A field study was carried out in the vicinity of a former battery recycling plant, with heavy metal content (Pb and Zn), the toxicological risk of seed consumption of soybean crops [Glycine Max (L.) Merr.] grown on these soils and their relation with seed quality being evaluated. The concentrations of Pb and Zn in soybeans (roots, stems, pods and seeds) and in top soils were investigated and their potential risk to the health of consumers was estimated. Furthermore, quality-related seed parameters (standard germination test, tetrazolium test, biomass and weight of 1000 seeds) were obtained. The results show that the concentrations of Pb in soybeans at all sites (controls and close to the smelter) were above the maximum permitted levels. Seed quality decreased as the lead concentration increased in seeds from sites near to the former battery recycling plant. Moreover, the greatest accumulation of Zn in seeds was found at sites with high concentrations of Pb in soils. Taking into account these findings, future studies need to be performed in order to evaluate the parameters influencing the mobility and bioavailability of toxic metals in agricultural soils, with the purpose of not only assessing the current state of crops in terms of food security but also evaluating possible soil remediation techniques. [ABSTRACT FROM AUTHOR]