Oregon State University researchers say it's possible to get a snapshot of the drug use in a particular community by drug-testing samples of wastewater from public sewage systems, the Associated Press reported Aug. 21.

Researchers recently tested samples from 10 U.S. cities and found wide variations in use of methamphetamine, for example. Drug-use patterns also emerged: cocaine and ecstasy use tended to peak on weekends, for example, while use of meth and prescription drugs remained steady throughout the week.

Tests for 15 different drugs were conducted; the most common substance detected was caffeine. "It's a community urinalysis," said Caleb Banta-Green, a researcher from the University of Washington who was part of the Oregon State team.

"Wastewater facilities are wonderful places to understand what humans consume and excrete," added lead researcher Jennifer Field, who wants to run similar tests on the wastewater of 40 Oregon communities.

The results of the study were unveiled at a recent meeting of the American Chemical Society.