Accumulation of lead, zinc and cadmium in plant seeds growing in metalliferous habitats in Bulgaria

Seeds from some plants were collected from metalliferous region in Bulgaria. In this area the concentrations of lead, cadmium and zinc in soil were 3500 mg kg−1, 280 mg kg−1 and 30 mg kg−1, respectively. Plants accumulate heavy metal ions in their seeds selectively. It appears that peanut and corn seeds accumulate mainly Pb (5.2–9.6 mg kg−1), pea seeds accumulate mainly Cd (1.0–1.2 mg kg−1 l), and wheat seeds accumulate mainly Zn (59.4–73.2 mg kg−1). This shows that the accumulation of heavy metals in the seeds of plants from some polluted regions may reach dangerous levels, especially if they are used as forage or food.