Graham Sustainability Institute

Environmental and Occupational Exposures To Mercury Among Indigenous People in Dunkwa-On-Offin, A Small-Scale Gold Mining Area In The Southwest of Ghana

November 2010

An analysis of mercury concentrations in human hair and urine sample of miners and farmers in a small-scale gold mining area of Ghana.

Total mercury concentrations in human hair and urine samples were determined to ascertain the extent of environmental and occupational mercury exposure in Dunkwa-On-Offin, a small scale gold mining area of the central-west region of Ghana. In all ninety-four (94) hair and urine samples comprising of forty (40) small scale miners and fifty-four (54) farmers were collected and analyzed for their total mercury levels using the cold vapor atomic absorption spectrometry. The hair total mercury concentrations ranged from 0.63 to 7.19 ug/g with a mean of 2.35 ± 1.58 ug/g for the farmers and 0.57–6.07 ug/g with a mean of 2.14 ± 1.53 ug/g for the small scale gold miners. There was no significant correlation between the total mercury concentration and the average weekly fish diet. The total mercury concentrations in urine of the miners were higher than those of the farmers and ranged from 0.32 to 3.62 ug/L with a mean of 1.23 ± 0.86 ug/L. The urine concentrations of farmers ranged from 0.075 to 2.31 ug/L with a mean of 0.69 ± 0.39 ug/L. Although the results indicate elevated internal dose of mercury the current levels of exposures do not appear to pose a significant health threat to the people.