The aim of the research is to reveal the reasons of contamination of tomato plants by heavy metals at the experimental plots with different degrees of remoteness and protection from anthropogenic influence using irrigation water from different sources. The contamination of tomatoes, grown at two different background experimental plots and two plots situated in zone of road influence by Fe, Mn, Cu, Zn, Pb, Cd, Co, Ni, were studied. Soil samples were taken by layers 0–5, 5–20 cm, where total and mobile water-soluble forms of heavy metals were determined. The same analyses were done for fruits, leaves, and stems of tomato plant. It is established that pollution sources of heavy metals were soil at the content of total forms of Pb (10 mg/kg), Mn (800 mg/kg), Zn (50 mg/kg), and Cu (20 mg/kg) and irrigation water, in which the increasing of Cd was in 3.5 and more times. Contamination of tomato leaves and stems by Cd (0.2 mg/kg), Ni (0.56 mg/kg), Fe (176 mg/kg) which provides by mineral silt of the soil and exhaust aerosols of motor transport were marked at the plot in Shchepkino, Zn (37 mg/kg), Cd (0.13 mg/kg), Fe (154 mg/kg) – at the plot in Dacha-1, Cd (0.2 mg/kg), Ni (13 mg/kg), Fe (414 mg/kg) – at the plot in Dacha-2, Pb (1.22 mg/kg), Cd (0.11 mg/kg), Ni (18 mg/kg), Fe (214 mg/kg) – at the plot Taganrog – Mariupol. The ranks of mobility for heavy metals at their transition from water-soluble compounds of soil to tomato plants have inversion what determines minimal intake of heavy metals by tomato plants, therefore the fruits of tomato grown at all sites had the content of heavy metals less than Clarke number for plants that is ecologically clean production.
Keywords: tomato, heavy metals, pollution sources, inversion of heavy metal mobility, total forms, mobile forms, water-soluble forms.
