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In South Africa the magnitude of Hg pollution was relatively low on the agenda in 2000,although a study by Pacina et al.[1] has ranked the country as the second highest anthropogenic emitter.This data was largely based on the Hg emissions from coal combustion and artisanal gold mining,reporting that South Africa contributes more than 10%to the global Hg emission budget [2].In 2013,the UNEP Global Mercury Assessment Report [3] has identified artisanal gold mining as the highest contributor to the global mercury budget.This presents South Africa with another challenge to fully understand its Hg footprint [4].The focus of this paper is to understand the role Hg has played in artisanal gold mining activities during the early stages of gold mining in South Africa.By quantifying the amount of Hg present in historical gold mining wastes,it is hoped that a possible prediction of Hg mobilisation,re-emission and persistence in the environment can be made [5].Environmental samples were collected in three areas in which artisanal gold mining has taken place in the past.This included the Pilgrims Rest and Barberton areas in the Mpumalanga Province,including the Krugersdorp area in the Gauteng Province.The results obtained for the freshwater and sediment samples have shown that the aquatic ecosystem is still impacted by elevated Hg concentrations.The TotHg concentrations in the freshwater samples collected in the Pilgrims Rest area ranged between 4 – 6 ng/L,while the MeHg concentrations ranged between 0.6 – 0.8 ng/L.The TotHg concentrations in the sediment ranged between 2 – 35 ng/g w.wt,with the MeHg concentrations ranging between 0.8 – 1.8 ng/g w.wt.In the Barberton area the TotHg concentrations in freshwater ranged between 0.1 – 16.6 ng/L,while the MeHg concentrations ranged between 0.05 – 0.87 ng/L.The TotHg concentrations in the sediment ranged between 5 – 413 ng/g w.wt,while the MeHg concentrations ranged between 0.1 – 5.1 ng/g w.wt.For the Krugersdorp area,the TotHg concentrations of the freshwater ranged between 0.8 – 26.7 ng/L,while the MeHg concentrations ranged between 0.02 – 0.89 ng/L.The TotHg concentrations in the sediment ranged between 0.45 – 48.49 ng/g w.wt,while the MeHg concentrations ranged between 0.11 – 5.26 ng/g w.wt.