Human health risk assessment of exposure to indoor mercury vapour in a Ghanaian artisanal small-scale gold mining community

Abstract People living or working in and around artisanal small-scale gold mining communities can be exposed to mercury vapour, which may negatively affect their health. In this study, the human exposure to air borne mercury in an artisanal mining community in the Upper East region of Ghana was investigated using Lumex RA 915 M mercury analyser, an active sampler. The concentration of mercury in air was measured inside and outside households and was related to human health risk standards. For each household, one measurement was taken from outside and three from inside at different positions. About 91% of the households where amalgam burning was reported had concentrations higher than the USEPA reference dose of 300 ng m−3 whereas 64% of the households where amalgam burning was not reported exceeded the reference dose above. The maximal (upper) instrumental limit (50,000 ng m−3) was passed for the highest concentrations, so, the upper 97.5% concentration was estimated, using censored statistics, to exceed 800,000 ng m−3 for the fireplaces. This exceeds any reported indoor household air concentration of Hg, identified by the literature review in this paper. Estimated hazard quotients were found to range from