Use of ash and mud for handwashing in low income communities
Epidemiological and microbiological data show that, in low income communities, as elsewhere, handwashing is particularly important in reducing the burden of infectious and parasitic diseases. These data also suggest that the efficacy of the handwashing process itself has a significant impact on the risk of disease transmission. A key factor is the extent to which pathogens are detached from the skin surface, by rubbing with appropriate materials prior to rinsing. In low income communities in developing countries, soil, mud or ash are still frequently used as an alternative to soap. In using mud, soil or ash as an alternative to soap, it is important to weigh the potential benefits, against the fact that these materials can become contaminated with pathogens and helminths, and can themselves act as a vehicle and source of gastrointestinal, parasitic and other infections. These materials can also contain potential toxic heavy metals such as arsenic, lead and chromium, as well as pesticides. The objective of this review is to bring together the available scientific data on the benefits and potential risks of using mud, soil and ash, as against soap, as against water only, for handwashing, and evaluate the factors which inform choice of the most appropriate agent in relation to the needs and constraints in different communities. The review was prepared by Professor Sally Bloomfield and Professor KJ Nath. The report was peer reviewed by Dr Stephen Luby (International Centre for Diarrhoeal Diseases Research, Bangladesh) and Dr Bilqis Hoque (Environment and Population Research Centre, Bangladesh).