Europe Samples Sewage Water to Find Its Biggest Drug Cities

The Belgian city of Antwerp is known for its Gothic cathedral and its skilled diamond cutters. It may also have a little-noticed drug problem. A new study revealed traces of cocaine, amphetamines, cannabis, and ecstasy in Antwerp’s sewage—all at levels among the highest of 42 European cities tested.

The study, published today in the British journal Addiction, represents the most extensive research yet in the emerging science of wastewater epidemiology. By testing samples of municipal sewage, researchers can see broad patterns in drug abuse, identify places where consumption is rising or falling, and even figure out what days of the week people tend to get high.