Look Ma, no drugs! How to drug test an entire community
You can give an entire community a drug test using just a teaspoon of wastewater from a city’s sewer plant!
“It’s a community urinalysis,” said Caleb Banta-Green, a University of Washington drug abuse researcher who was part of the Oregon State team…The ingredient Americans consume and excrete the most was caffeine, said Jennifer Field, the lead researcher and a professor of environmental toxicology at Oregon State.
She said that one fairly affluent community scored low for illicit drugs except for cocaine. Cocaine and ecstasy tended to peak on weekends and drop on weekdays, she said, while methamphetamine and prescription drugs were steady throughout the week.
As Bruce Schneier points out, you won’t identity individual users, but if you did push the sample high enough into the pipe, you can test groups of houses or even individual houses.