1. Environmental Health and Ecological Sciences, Ifakara Health Institute, P.O. Box 53, Ifakara, Morogoro, Tanzania
2. Maji Safi kwa Afya Bora (MSABI), P.O. Box 284, Ifakara, Morogoro, Tanzania
3. Pollution Research Group, Chemical Engineering, University of KwaZulu-Natal, Durban 4041, South Africa; Water Research Centre, The University of New South Wales, Kensington, NSW 2052, Australia; andSchool of Civil Engineering, The University of Sydney, Darlington, NSW 2008, Australia