Contamination levels and human health risk assessment of mercury in dust and soils of the urban environment, Vanadzor, Armenia

Abstract Mercury has unique chemical features which predetermine its migration and accumulation behaviors in the environment. In this regard, the studies devoted to the identification of Hg contents and pollution issues should consider both transit and deponent medium such as air dust and soils, respectively. This paper aimed at exploring spatial distribution characteristics, pollution levels and human health risk of Hg in dust and soils of Vanadzor urban area. A total of 42 street dust, 13 leaf deposited dust and 84 soil samples were collected from an area covering the entire territory of Vanadzor, encompassing residential and industrial sites. The potential hazard associated with Hg was assessed with the use of geo-accumulation index, enrichment factor and potential ecological risk index. The spatial distribution of concentrations of Hg suggested that high values were detected near the Chemical Plant and on high traffic streets, indicate the possible anthropogenic origin of Hg. According to geo-accumulation index, most of the samples in street dust were characterized as moderately polluted, in leaf deposited dust – from unpolluted to moderately polluted levels and all soil samples were characterized by unpolluted levels. Enrichment values are significantly higher in dust samples compared with soils. The potential ecological risk assessment showed that high, considerable, and low levels of ecological risk dominated in the street dust, leaf deposited dust and soils in the City area, respectively. The results of health risk assessment showed that detected contents of Hg are not risky for the health of the population.