Soil tungsten contamination and health risk assessment of an abandoned tungsten mine site

Abstract

The mining and beneficiation of tungsten ores, including waste treatment and tailings disposal, may cause soil contamination in the mining area and environments. Few studies have addressed soil contamination in tungsten mine sites. The current research quantitated the leachates in the surface and subsurface soil samples from mining and beneficiation areas, peripheral area, sand-making area, dumping area, and tailings pond of an abandoned tungsten mine site in Ganzhou City, Jiangxi Province of China. We further evaluated the degree of soil tungsten pollution and the risk to human health. The results showed that soil tungsten contamination mainly occurred in the sand-making area where tailings were used to make sand. The highest tungsten content in the surface and subsurface soils of the sand-making area was 1250 and 3020 mg/kg, respectively, exceeding the EPA's Regional Screening Level of tungsten (930 mg/kg) for industrial land use. The leaching concentrations of soil tungsten had similar distribution patterns to that of total soil tungsten, with the highest leaching concentration (0.860 mg/L) found in the sand-making area. The geo-accumulation index evaluation indicated heavy tungsten contamination at the sand-making area and tailings pond. The hazard quotient (HQ = 1.34) of tungsten contamination in the surface soils of the sand-making area exceeded the acceptable level (HQ = 1), implying a significant risk to human health. The present study provided valuable information for pollution control and risk management of soil contamination in tungsten mine sites. CAPSULE: We studied the degree of soil tungsten pollution and health risk assessment in an abandoned tungsten mining area to provide helpful information for soil pollution control and risk management in China's tungsten mining areas.

Keywords: Geo-accumulation index; Health risk assessment; Leaching; Soil contamination; Tungsten mine site.