Traces of illicit drugs in municipal wastewater could be used to pinpoint consumption hotspots and perhaps target treatment and prevention services more effectively, according to a new study.

Researchers in Oregon collected untreated wastewater samples from 96 communities statewide on a single day -- March 4, 2008 -- and analyzed them for the presence of methamphetamine, cocaine, and ecstasy. They found that traces of cocaine were higher in urban areas and barely present in rural areas, while methamphetamines were found in samples gathered from both rural and urban communities. Traces of ecstasy were only found in about half the samples, but tended to be more present in urban wastewater.

Testing wastewater for drugs could allow public-health officials to better track drug consumption patterns across communities and over time, according to researchers from Oregon State University, the University of Washington, and McGill University.

"This work is the first to demonstrate the use of wastewater samples for spatial analyses, a relatively simple and cost-effective approach to measuring community drug use," said University of Washington researcher and study lead author Caleb Banta-Green. "Current measures of the true prevalence of drug use are severely limited both by cost and methodological issues. We believe these data have great utility as a population measure of drug use and provide further evidence of the validity of this methodology."

"We believe this methodology can dramatically improve measurement of the true level and distribution of a range of illicit drugs," added Banta-Green. "By measuring a community's drug index load, public-health officials will have information applicable to a much larger proportion of the total population than existing measures can provide."

The study was published online in the journal Addiction.