Health

Abstract

As the children’s book reminds us, everyone poops. They pee too. Then they flush all that solid and liquid waste down the toilet to the sewer system, where it joins everybody else’s waste and wends its way to a wastewater treatment plant.Because all that excrement contains chemical remnants of the food people ate, the cigarettes they smoked, and the medications they took, the wastewater treatment plant is a rich source of information about the health of the population it serves.The sewage that flows into the facility can be thought of as a pooled urine and stool sample of every person whose sewage is treated there. Any tests that would be run on an individual’s sample—monitoring for illicit drug use, for instance—can conceivably be undertaken at a population level in a treatment plant. That’s the basis of the field of study researchers are calling wastewater-based epidemiology.“If you are at the mouth