Chemical characteristics and health hazards of heavy metals in shallow groundwater: case study Anloga community, Volta Region, Ghana

Abstract

Five water samples each were collected from six shallow wells which serve as source of drinking water at different locations within the Anloga community of the Volta Region in Ghana. Samples were analyzed for physicochemical characteristics, and human health risk associated with the consumption of heavy metals in the samples was also assessed. The results showed that pH, EC, water hardness, fluoride and sulfate levels were below the maximum permissible levels recommended by the WHO for drinking but chloride and nitrate levels in well A6 were above their respective WHO limits. Concentration of heavy metals showed Cd and Pd toxicities in some of the wells since their concentrations were higher than the WHO accepted limit for drinking water. Estimated non-carcinogenic health risks of the metals through ingestion were less than 1 in some of the wells, indicating small to no health hazard; however, high non-carcinogenic risk was recorded in well 2, 3 and 5 indicating a potential health hazard to the local residents. Health risk through dermal injection of the metals was found to be less than 1, indicating no health risk associated with water samples via dermal absorption. Cancer risk computed for Cd ranged from 1.82E−02 in well A5 to 9.09E−02 in well A1 and A6, indicating that consumption of water from these wells could result in an excess of 2–9 cancer cases per 100 people. The risk of developing cancer from Pb as a result of consuming water from wells A1, A2 and A5 was estimated to be 3.69E−06.