Bioaccumulation of heavy metals in garlic bulbs (Allium sativum L.) in correlation with soil from private gardens in the Copșa Mică area, Romania

Abstract

Heavy metal contamination of soil and plants is a worldwide concern. Copșa Mică in Romania is one of the areas in the country known to have a high level of pollution. Even if metallurgical activities have been reduced or stopped the soil is still polluted. This study aimed to estimate the bioaccumulation of heavy metals (Cd, Pb, Zn and Cu) in soil from garlic bulbs (Allium sativum L.) from individual gardens in the Copșa Mică polluted area, Romania. The bioaccumulation of heavy metals in garlic bulbs was estimated based on a data set collected from 44 individual gardens. The value of the linear correlation coefficient between the total cadmium content in the soil and that in the plant was significantly different from zero, indicating a close correlation between the two variables (r = 0.775***). In addition, for zinc (r = 0.649***) and lead (r = 0.423**), simple power-type regressions were found to be best for estimating the bioaccumulation of these elements in garlic bulbs. Only for copper, the value of the linear correlation coefficient was not significantly different from zero (r = 0.274ns), indicating that the estimation of copper accumulation in garlic cannot be described by simple power-type regressions. The results of this study are important for estimating the accumulation of heavy metals in garlic bulbs (head), which are often consumed by the population.