Wastewater is used in agriculture in many parts of Africa and this practice has implications for both human and ecosystem health.
Heavy metals in contaminated wastewater pose several risks to humans through assimilation pathways such as the ingestion of plant material (in the food chain). Heavy metals also destroy soil organisms that are responsible for nitrogen fixation, increase drainage and soil aeration. Although the metal concentrations in domestic wastewater effluents are usually relatively low, long-term irrigation with wastewater can eventually result in heavy metal accumulation in the soil (Wuana and Okieimen 2011).
From collection: Sanitation and Wastewater Atlas of Africa - Ecosystems