An Assessment of Some Heavy Metal Levels in Drinking Water and Social Characteristics in Buruli Ulcer Endemic and Non-Endemic Communities in the Amansie West District

Abstract

Buruli ulcer (BU) is a skin disease caused by Mycobacterium ulcerans (MU). It is often associated with slow-flowing or stagnant water and increase in incidence of the disease is also associated with ecological transformation. Several risk factors have been identified, and a number of transmission mechanisms suggested. However, the exact mechanism of transmission and development of BU through water-related human activities is unknown. A study was carried out to compare concentrations of cadmium, lead and aluminum in drinking water samples and some social characteristics from endemic and non-endemic communities in the Amansie West District in Ghana. Sixty-six drinking water sources were sampled from boreholes and hand-dug wells in the study area. The analysis of the samples showed that the average concentration of cadmium was significantly higher (p < 0.05) in endemic communities than in non-endemic communities even though all the values were below the WHO guideline values of 0.003mg/L. The average concentrations of lead and aluminum were lower in endemic communities than in non-endemic communities, but the differences between the average concentrations were not statistically significant (p > 0.95 for lead, p > 0.30 for aluminum). Aluminum concentrations in all the samples were however lower than the WHO recommended guideline value of 0.1mg/L, whilst the concentration of lead was higher than the recommended guideline value in several communities.  It was therefore concluded that cadmium, lead and aluminum may not contribute to the occurrence and transmission of BU. In relation to the social characteristics, the educational level was generally poorer in endemic areas than in the non-endemic areas. The endemic communities used poorer source of water which include streams and hand-dug wells, unlike non-endemic communities which had better sources of water - boreholes and pipe-borne water only. Field observation showed that people in the endemic communities walked barefooted, whilst those in the non-endemic communities had footwear. In this District therefore, attitudinal behaviour/social characteristics may play a role in the occurrence of the disease. Other heavy metals like arsenic should be investigated into, as well as the water usage patterns of the people in the community (to determine whether the disease is water-washed, water-borne or water-based). The organism may be present in the water and/or soil, and it is recommended that more research be carried out to isolate it in the environment.

Keywords: Buruli ulcer, Drinking-water, Amansie West, Heavy metals