It's amazing how something as simple as a toilet, that we take for granted everyday, is such a monumentally difficult thing to re-engineer cheaply for the world's poor.
Many cabins in the mountains in Norway use thick plastic bags that you just tie off and dump in a skip when you leave. At least they did last time I rented one twenty years ago, so the general idea is not new. Sealing the waste in with a biodegradable film is a neat idea though and makes a lot of sense for a hot climate.
That's because our toilets are unsustainable. The problems of the poor are hard to solve because the rich solve problems by pushing them off onto the poor. The poor don't have anyone to push their shit on because they are the people shit gets pushed on.
If we're still talking about toilets, this really depends on local conditions. In USA east of the Rockies, typical flush toilets aren't inherently problematic. In areas with less water, they are.
It's amazing how something as simple as a toilet, that we take for granted everyday, is such a monumentally difficult thing to re-engineer cheaply for the world's poor.