In the slums of the Kenyan capital, Nairobi, visiting the bathroom usually means one of two things: a trip to the local pit latrine or the flying toilet

The former entails letting nature take its course in a rickety outhouse perched atop a hole in the ground - a facility also used by hundreds of other people in the neighborhood. The latter meanwhile consists of relieving oneself in a plastic bag before throwing the offending item away in the street. A 2011 report by the Bill and Melinda Gates Foundation found that these arrangements led to environmental contamination and the spread of diseases such as typhoid and tuberculosis. In Kenya alone there are 10 million people who live in the slums and 8 million of them don't have access to a clean toilet.