Rare Earth Elements Transfer from Soil to Vegetables and Health Risks Associated with Vegetable Consumption in a Former Mining Area

Abstract

Rare earth elements (REEs) and 18 other elements in the vegetables (carrot, parsley, cabbage, potato, onion) and soils from two villages near tailings management facilities in the Baia Mare area, NW Romania, were measured. The soil-to-plant transfer and the health risks posed by the consumption of these vegetables were also assessed. The pseudo-total concentrations of elements varied widely in the soil and vegetables, with the lowest concentrations being found for Ta (2.1 µg/kg) and the highest for Fe (9219 mg/kg). The concentration of total light REEs (LREEs) was considerably higher than that of heavy REEs (HREEs). The percentages of available elements were <20% of the pseudo-total concentration, except for Zn, Cd, and Pb, where the available fractions were much higher. Generally, the soil-to-plant transfer factors decreased in the following order: parsley > onion > cabbage > carrot > potato, and varied from element to element. The LREEs were less absorbed than the HREEs in all investigated vegetable species. Pearson correlations revealed strong positive correlations between the lanthanides, except for Eu, in the soil and vegetables. No important health risks following the consumption of vegetables were found for REEs, the estimated daily intake of REEs through vegetable consumption being much lower than the acceptable daily intake.