HEAVY METAL CONTAMINATION OF SOIL IN BAIA MARE MINING AREA

In the Baia Mare area, located in North-Western Romania, around an industrial complex involved in mining, metallurgical and chemical activities, the environment and particularly the soils are polluted due to the acid rains and heavy metals. The soils in this area are affected by the emissions from these industrial activities. From environmental point of view, all heavy metals are very important because they cannot be biodegraded in soils, so they tend to accumulate and persist in urban soils for decades. Lead, cadmium, copper, zinc and nickel are metals frequently reported to have a high impact on organisms. Heavy metal pollution of soil enhances plant uptake causing accumulation in plant tissues and eventual phytotoxicity. In Baia Mare, 35 soil samples were collected covering the whole area ( industrial and residential). The concentrations of heavy metals were determined by inductively coupled plasma atomic emission spectrometry after aqua regia digestion. The obtained results showed that the concentrations of Pb exceeded the intervention level for all samples; for Cu and Zn concentrations, the half of samples exceeded the intervention level; for Cd concentrations, one third of samples exceeded intervention level; for As concentrations, the majority of samples exceeded alert level; Cr concentrations exceeded alert level for two samples; and the alert level for Ni has not been exceeded.