Assessment of Heavy Metals (As, Cd, Hg, Pb) in Sources of Water for Human Consumption in Sub-Saharan Africa: A Literature Review

Abstract

In the world and particularly in Africa, the supply of drinking water by rural communities is still a challenge to be met due to the unavailability of water in quality and quantity. Indeed, 76% of the population in sub-Saharan Africa does not have access to drinking water. This situation is more pronounced in rural and peri-urban communities than in urban areas. Some communities, particularly in rural areas, are therefore condemned to consume surface water, rainwater and well water of dubious quality due to the contamination of this water and especially the lack of a drinking water distribution network. Several research studies on metal contamination of surface water, groundwater and rainwater have reported high levels of metals. This review article focuses on the contamination of waters in sub-Saharan Africa by cadmium, lead, mercury and arsenic, because of their toxicity and the health and ecotoxicological consequences linked to their presence in water. These are heavy metals at the origin of several dangerous diseases such as lead poisoning, hydrarygysmus, Itai Itai disease, etc. This article reviews the problems of accessibility to drinking water in communities in terms of quantity and quality, the origins and levels of water contamination by metals as well as analytical methods for metals and the consequences related to the consumption of these waters.