Pollution Characteristics and Risk Assessments of Mercury in the Soil of Chami (Dakhlet Nouadhibou, Mauritania): Preliminary study

Due to the rapid expansion of mining, the economy of town of Chami in Mauritania has experienced swift growth. However, this rapid expansion brings the risk of soil pollution by mercury (Hg) as a result of increased mineral processing activities. In order to study the characteristics of soil Hg pollution in Chami and assess the health risk, a total of 14 samples were collected from seven sites from the town of Chami. The results revealed that the soil Hg concentration varies widely from 0.0061 to 0.658 mg/kg with an average of 0.233 mg/Kg in first campaign. In second campaign, the soil Hg concentration varies widely from 0.063 to 0.819 mg/kg with an average of 0.258 mg/Kg. The results of the laboratory analysis were further elucidated using pollution indices such as the Single Pollution Index, Contamination Factor, Ecological Risk Factor and the Geo-accumulation Index. These environmental indices revealed that the soil is seriously polluted with Hg. However, the values of the total non-carcinogenic risk assessment index (HI) were found to be far less than 1. These results reveal that the soil of the town of Chami does not pose any risk to human health.