SA Students Invent 'Urine Bricks' (PHOTO)

University students in South Africa say they have created new environmentally-friendly bricks using human urine.

The students from Cape Town combined urine collected from men's toilets with sand and bacteria - in a process that allows the bricks to solidify naturally at room temperature.

They say an enzyme in the mixture breaks down the urine to produce calcium carbonate - a key component of limestone - which binds the other materials together.

Regular bricks need to be baked in high-temperature kilns, that produce large amounts of carbon dioxide.