Adopting a strategy from Europe, the federal Office of National Drug Control Policy (ONDCP) is trying to get a handle on drug-use rates by testing sewage from Fairfax County, Va., for signs of cocaine use, the Washington Post reported March 27.

Federal surveys estimate that 2.5 percent of county residents use cocaine; the sewage study seeks to verify that data by measuring cocaine metabolites from the urine of drug users. "It's a very strange request," said Fairfax County Board of Supervisors Chairman Gerald E. Connoll. "We're ready to do anything and everything we can do to eliminate illicit drug use. But I'd want to know a lot more about what this will actually lead to." 

ONDCP officials say it's unclear if studying sewage is any more accurate than surveys in measuring drug use. But David Murray, an assistant to drug czar John Walters, said officials think the project "will be very, very useful."

Sewage samples gathered over five days in March have been sent to the Armed Forces Institute of Pathology for analysis; researchers will be measuring traces of benzoylecgonine, a cocaine metabolite.

A similar study in Milan, Italy concluded that more than twice the number of residents were using cocaine as previously estimated in surveys.