Health and environmental risk assessment of mercury in outdoor and indoor dust in artisanal and small-scale gold mining area in Amansie-west district in the Ashanti Region of Ghana

Mercury (Hg) pollution around artisanal and small-scale gold mining (ASGM) areas has been of much concern. Many studies have reported elevated Hg concentrations in environmental media and human hair, but studies on dust relating to inhalation exposure of Hg are limited. In this study, we investigated mercury (Hg) in indoor and outdoor dust to reveal environmental and human health risk around ASGM in Amansie West district, Ghana. Indoor and outdoor dust samples were collected from Manso Abore and Manso Nkwanta in Ashanti Region, Ghana. The Mean and median value of Hg concentration in the indoor dust were 2.2 ± 3.6 mg/kg ( n  = 31) and 0.72 mg/kg respectively while that of the outdoor dust were 0.19 ± 0.48 mg/kg ( n  = 60) and 0.042 mg/kg, respectively. Mean and median Hg concentration in indoor dust were about 11 and 17 times higher respectively than that in the outdoor dust. The Hg concentration in the indoor dust of the miner was statistically significantly higher than that of the non-miner in Manso Abore ( p  < 0.05) but was not significant in Manso Nkwanta. The geo-accumulation index of the outdoor dust ranged from unpolluted to extremely polluted while that of the indoor dust ranged from moderately polluted to extremely polluted. Health risk assessments suggested that there was no potential non-carcinogenic health effect for Hg exposure relating to the dust to residents living in rooms of miners and non-miners.