British engineers have developed a simple water filter which could save thousands of lives in developing countries.
Unlike the commercial water filters currently supplied by some charities, the unit designed by Dr Paul Sallis and colleagues at Newcastle University, UK, can easily be made by local craftsmen and women, using local materials.
The 'low tech' manufacturing process overcomes the problems of having to persuade and educate low-income families to use water filters and of having to order costly spare parts when a filter breaks down.
But after successful trials, the project has not been widely implemented because it does not qualify for support from the development agencies, falling into a 'no man's land' between research and commercial products.
Charities estimate that more than a billion people do not have access to safe drinking water. In some parts of Africa, water-borne diseases such as cholera, dysentery and viral diarrhoea claim the lives of one in four children.
The United Nations has deemed such infant mortality rates as unacceptable. One of its eight Millennium Development Goals is to 'reduce by two-thirds the mortality rate among children under five'. This goal is one of the keynote topics at the 2006 World Water Congress in Beijing, today, Monday 11 September.
The Newcastle project began after a group of postgraduate civil engineering students visited Ghana, Kenya and Malaysia and recognised the huge benefits that sustainable water filtration could have on health. One of the students, Matt Simpson, decided to devote his doctoral research project to this topic.
Working in the laboratories at Newcastle University, he tested many techniques and eventually discovered that a mixture of clay and crop residues - such as rice husks or bran - created the ideal ceramic filter, when fired at 700 to 1,000C.
At these temperatures the crop residue decomposes, releasing carbon dioxide gas which forms microscopic por
Contact: Dr Paul Sallis
University of Newcastle upon Tyne