Mercury in soil and perennial plants in a mining-affected urban area from Northwestern Romania

Abstract

The mercury (Hg) concentrations were evaluated in soils and perennial plants sampled in four districts of Baia Mare city, a historical mining and ore processing center in Northwestern Romania. The results showed that the Hg concentration exceeded the guideline value of 1.0 mg kg⁻¹ dry weight (dw) established by the Romanian Legislation, in 24 % of the analyzed soil samples, while the median Hg concentration (0.70 mg kg⁻¹ dw) was lower than the guideline value. However, Hg content in soil was generally higher than typical values in soils from residential and agricultural areas of the cities all over the world. The median Hg concentration was 0.22 mg kg⁻¹ dw in the perennial plants, and exceeded the maximum level of Hg (0.10 mg kg⁻¹) established by European Directive 2002/32/EC for plants used in animal feed in order to prevent its transfer and further accumulation in the higher levels of food chain. No significant correlations were found between soil Hg and other analyzed metals (Cd, Cu, Pb, Zn) resulted from the non-ferrous smelting activities, probably due to the different physicochemical properties, that led to different dispersion patterns.

Keywords:

• Mercury
• urban soil
• perennial plants
• Baia Mare
• TD-CV-AAS
• multivariate analysis.

Acknowledgments

This work was carried out with support from the Romanian Ministry of Education and Research, PNCDI II Program (Project CISPPA no. 52157/2008).