The water drunk by astronauts on the International Space Station is recycled by up to 80% from their sweat, urine and other sources. Recycling reduces the number of supply missions needed for the Station, and building a self-sufficient spacecraft will be necessary for future mission farther from our planet. Flight surgeons and astronauts closely monitor the quality of the drinking water, and the Aquapad experiment that ESA astronaut Thomas Pesquet will run in space aims to simplify the regular testing. Although developed for space, the technology behind Aquapad is clearly useful on Earth, for example, in disaster-stricken areas, where water could be contaminated. See http://www.esa.int/spaceinimages/Images/2016/10/Testing_the_waters
