A comparative study of the pollution status of Sakumo II and Muni lagoons in Ghana.

The pollution status of Sakumo II and Muni Lagoons and Mamahuma and Gbagbla Ankonu feeder streams, which feed Sakumo II along the coast of Ghana, were assessed and compared. As expected of saline waters, pH values of both lagoons fell within a slightly neutral to saline range whilst, the feeder streams were moderately saline. Conductivity distribution also showed saline (>5.0 mS cm(-1)) characteristics of the lagoons, while, the feeder streams are brackish (1.5-5.0 mS cm(-1)). DO concentrations in both lagoons indicated a wide variation. Relatively high BOD and nutrients content of Sakumo II and the feeder streams suggested that, Sakumo II and its feeder streams are moderately to grossly polluted. However, Muni Lagoon was characterized by relatively low BOD and nutrients content suggesting relatively low anthropogenic impact. The ionic dominance patterns for Sakumo II and Muni Lagoons were: Na(+) > Mg(2 + ) > Ca(2 + ) and Cl(-) > HCO(3)(-) > SO(4)(2-), Na(+) > Ca(2 + ) > Mg(2 + ) and Cl(-) > HCO(3)(-) > SO(4)(2-), respectively. Using water quality index (WQI), Sakumo II was found to be grossly polluted and requires mitigation measures, while, Muni Lagoon was of fairly good quality and requires monitoring.

Contamination status of arsenic and other trace elements in drinking water and residents from Tarkwa, a historic mining township in Ghana.

This study was conducted to assess the contamination status of 22 trace elements, especially As in water and residents in Tarkwa, a historic mining town in Ghana. Drinking water and human urine samples were collected from Tarkwa in addition to control samples taken from Accra, the capital of Ghana in March, 2004. Concentrations of As and Mn in some drinking water samples from Tarkwa were found above the WHO drinking water guidelines posing a potential health risk for the people. A potential health risk of As and Mn is a concern for the people consuming the contaminated water in this area. No significant difference of As concentrations in human urine between mining town (Tarkwa) and control site (Accra) was observed. Although As concentrations in drinking water in Tarkwa were low, urinary As levels were comparable to those reported in highly As-affected areas in the world. These results suggest the presence of other sources of As contamination in Ghana. This is the first study on multi-elemental contamination in drinking water and human from a mining town in Ghana.