Objective The aims were to quantitatively analyze the sources of heavy metals in soils and assess health risks in the industrial belt on the northern slope of the East Tianshan Mountains, including Midong District, Fukang City, Jimusaer County, and Qitai County. The study analyzed the concentrations of six heavy metals (Zn, Cu, Cr, Pb, Hg, and As) in 68 surface soil samples from the region.
Method The geostatistics, potential ecological risk index, correlation analysis, UNMIX model, and health risk assessment models (USEPA) combined with Monte Carlo simulation were employed to evaluate ecological risks of soil heavy metals and identify their sources.
Result ①Except for Cu and Cr, concentrations of Zn, Pb, Hg, and As in soils exceeded Xinjiang's background values by 1.19, 2.11, 3.18, and 2.90 times, respectively. Meanwhile, As exceeded China's agricultural soil screening values by 1.02 times. ②Spatially, Zn, Pb and Hg were predominantly enriched in the southwest and central-southern parts of the study area, while Cu was concentrated in the northwest and central areas, and Cr accumulated mainly in the central-southern parts. As showed a more scattered distribution. ③The potential ecological risk index showed that Hg content in 98.53% sample sites, As content in 19.12% sample sites and 63.25% sample sites in the study area were at moderate risk or above. ④Soil heavy metal pollution in the study area primarily originated from mixed sources composed of transportation and industrial emissions, atmospheric deposition, and mixed sources from transportation and parent materials for soil formation. ⑤Both non-carcinogenic risk (Hazard Index, HI) and carcinogenic risk (Carcinogenic Risk, TCR) were relatively high in the study area. As was the main contributor to non-carcinogenic risk, while Cr and As were significant contributors to carcinogenic risk.
Conclusion Hg and As would cause the significant environmental hazards in the study area, while As and Cr would cause substantial health risks to humans.
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