The purpose of this paper was to determine the distribution of some heavy metals from the soil in root vegetables, cultivated in a plain area of Banat: Cenad place, area considered unpolluted with such metals. The physico-chemical properties of the soils and surface waters, also the climatic factors specific to this area, allows ecological production and encourages the cultivation of vegetables with a normal content of heavy metals. The concentrations in Cd, Co, Cr, Cu, Fe, Mn, Ni and Zn from the soil (total and mobile forms) and from some root vegetables (total concentration) were determined: carrot, parsley, celery and potatoes. The obtained results of the heavy metals determination, made by atomic absorption spectrometry in acetylene-air flame method (FAAS), shows that their distribution in soil and vegetables is non-uniform, depending on the nature of the metal and also vegetables. The analysis of heavy metals contents from carrots, parsley, celery and potatoes show that the vegetables contain significant amounts of essential mineral elements and insignificant contents of toxic or potentially toxic metals. Translocation of heavy metals from soil to the plant is conditioned by a series of factors, among which the most important are the nature of the heavy metal, the physicochemical soil properties, the mineral needs of the plant. Considering the accessible concentrations (mobile forms) of heavy metals in the soil and the average heavy metal concentrations in the vegetables (average values for the four analyzed vegetables) it can be stated that fraction of metal translocated from soil to vegetables has the following values (%) : 13.79 (Fe), 3.82 (Mn), 91.99 (Zn), 24.73 (Cu), 70.83 (Co), 62.32 (Ni), 76.32 (Cr), 2.98 (Pb) and <15 (Cd). For a healthy nutrition it is very important to know these contents. The concentrations of heavy metals in the soil samples and in the analyzed vegetables are below the toxicity limits provided by the legislation. Therefore, vegetables grown in this area do not present a risk of contamination with heavy metals.

heavy metals, soil, root vegetables, FAAS

sciences soil

Presentation: poster