Sun, salt and lime sounds like the beginnings of a cocktail recipe, but for some, it could mean cleaner, life-sustaining water.
In many developing countries, the only source of water is contaminated with viruses and bacteria. In fact, the United Nations estimates that 1 in 6 people don't have access to enough fresh drinking water.
Pouring water into clear plastic bottles and placing them in the sun can kill disease causing organisms in about six hours. It's a simple and cheap method that's been around forever, and it helps. (Who says sun tea isn't safe?)
But there's a hitch – the water has to be clear enough for the sun's rays to penetrate – and much of the world's water supply is murky from the clay soils in riverbeds and lake bottoms that mix with the water. Enter the scientists.