At the recently held Fourth World Water Forum in Mexico City, hundreds of governmental agencies, international organizations, environmental groups and private sector companies promoted ideas and projects aimed at conserving water and improving sanitation. As VOA's Greg Flakus reports, one idea being promoted by several European groups would change the way the world uses water to eliminate human waste.
Modern sanitation systems around the world use millions of cubic meters of water everyday to rid homes and businesses of human waste.
Environmentalists from Germany and Scandinavia believe there is a better way. They came to the World Water Forum to promote a dry, composting toilet.
This toilet separates human urine and human feces and stores them in separate compartments.
The resulting material can then be used as fertilizer, according to the Stockholm Environmental Institute's Cecilia Ruben. "This is the compost. This is what comes out, depending on the climate and the technology that is used, it takes anywhere from two months to six months to have the material sanitized."
Ruben insists that the human waste compost is safe and effective, especially the urine.
"Human urine has basically the same composition as commercial fertilizer and, therefore, with some treatment or with storage, in fact, it is enough, you can apply it to the fields -- and we have guidelines on how it can be applied -- and it is very safe and produces very good growth in various crops."
But not everyone agrees. Some environmentalists and development experts see composting toilets as a reversion to primitivism that could be dangerous.
Iain Murray, Senior Fellow at the Competitive Enterprise Institute in Washington DC is among the skeptics. He told us, "Generally speaking, handling human waste matter is not particularly safe. That is one of the reasons why, throughout human history, the main aim of sanitation has been to get rid of this stuff and not to use it in our own back yards."
Murray worries that well-meaning groups from industrialized nations, like Sweden, may be imposing their values on poor people who would rather have better water systems and flush toilets.
"I think this is an example of what I like to call 'Green Imperialism,' which is where the developing world is having moral values imposed on it by the developed world, which has already gone through a lot of the problems that the developing world is facing at the moment," says Murray.
But Linus Dogerskog, who has helped introduce composting toilets in West Africa, says years of experience shows they are safe and effective. "It is proved that it can be done, it is proved that it can be done without great health risks."
He says people in many parts of the world now view human excreta as a resource rather than something unclean and hazardous. "We are on the verge of going to scale in West Africa and in many parts of the world there are pilot projects on the verge of going to scale. In China they have constructed one million units."
Linus Dogerskog says he plans on installing one of these toilets in his home in Sweden.
"It is the future," he says.