Wastewater from sewage that is churned out by expanding cities and towns worldwide helps meet food security globally, especially in developing regions. It is the one resource (unlike land, labour, or freshwater) that is continuously growing in volume and used to cultivate vegetables, grains, animal feed, and fish at a larger scale than we ever realised.
A new study shows how widespread this practice is among farmers who grow our food. Using satellite images, geo spatial data sets, and computer modelling of the water cycle, the report estimates that because most wastewater remains untreated 885 million people are at health risk through the food chain, not counting those otherwise in contact with the water.