Anchor Lisa Mullins speaks with Arno Rosemarin about the potential of dry composting toilets to help solve the world's sanitation crisis. Rosemarin runs the ecological sanitation project at the Stockholm Environment Institute.

Rosemarin is an expert on sanitation.

But why talk about toilets? Because even today — in the 21st century — a third of the world does not have access to basic sanitation. The result: water and soil pollution, and widespread health problems like cholera and dysentery.

Sanitation is “something that human beings have… trouble talking about,” says Rosemarin. But he contends we must get over our aversion to the subject if we are to solve the earth’s sanitation challenges.

So how can we provide basic sanitation to those who don’t have access to it? And would you be willing to trade your flush toilet for a more earth-friendly design?