Comparative assessment of mineral elements and heavy metals accumulation in vegetable species

Abstract

The heavy metal (cadmium, lead, nickel, chromium) and mineral element (potassium, phosphorus, calcium, magnesium) levels in edible parts of tomato, potato, spinach, beetroot, parsley, parsnip, carrot, cauliflower, pepper and broccoli were determined by atomic absorption spectrophotometry. Six samples for each species originating from different localities were collected from green markets. The heavy metal concentrations ranged from <0.01 to 2.37, <0.01 to 7.72, <0.01 to 5.37 and <0.01 to 9.31 g/g for cadmium, chromium, nickel and lead, respectively. The order of the macroelement concentrations in dry matter for all vegetable species was as follows: potassium > calcium > phosphorus > magnesium. The highest mean levels of the heavy metals, as well as of potassium, calcium and magnesium, were found in spinach. A large number of samples containing high levels of toxic heavy metals, especially of cadmium and lead, impose the necessity for strict regulative guidelines concerning individual vegetable crops production, harvest, handling and storing, in order to diminish possibility of contamination.