LOWDOWN ON CITIES' DRUG USE FLUSHED OUT IN SEWAGE

Researchers Study Levels of Illicit Narcotics

Which city uses more cocaine: Los Angeles or London? Is heroin a big
problem in San Diego? And has ecstasy emerged in rural America?

Environmental scientists are beginning to use an unsavory new tool,
raw sewage, to paint an accurate portrait of drug abuse in
communities. Like one big, citywide urinalysis, tests at municipal
sewage plants in many areas of the United States and Europe have
detected illicit drugs such as cocaine, methamphetamine, heroin and marijuana.

Law enforcement officials have long sought a way to make reliable and
verifiable calculations of narcotics use, to identify trends and to
formulate policies. Surveys, the backbone of drug-use estimates, are
only as reliable as the people who answer them. But sewage does not lie.

Because people excrete chemicals in urine and flush it down toilets,
measuring raw sewage for street drugs can provide quick, fairly
precise snapshots of drug use in communities, even on a particular day.

The results have been intriguing: Methamphetamine levels in sewage
are much higher in Las Vegas than in Omaha, Neb., and Oklahoma City.
Los Angeles County has more cocaine in its sewage than several major
European cities. And Londoners apparently are heavier users of heroin
than people in cities in Italy and Switzerland.

"Every sample has one illicit drug or another, regardless of
location," said Jennifer Field, an environmental chemist at Oregon
State University who has tested sewage in many U.S. cities. "You may
see differences from place to place, but there's always something."

The practice of testing sewage has illuminated an environmental
threat: Many urban waterways are contaminated with low doses of
cocaine and other illicit drugs from treated sewage.

So far, this "sewage forensics" or "sewage epidemiology" has not been
widespread. Treatment plants do not monitor sewage regularly for
street drugs. The Environmental Protection Agency is planning to add
illicit drugs to the array of substances that could be monitored
daily at treatment plants.

Unlike prescription drugs and personal-care products, which are a hot
topic in environmental contamination, illicit drugs have long been
below the radar.

Christian Daughton, chief of environmental chemistry at the EPA's
National Exposure Research Laboratory, first proposed the tests in 2001.

"To me, chemicals are chemicals. All chemicals, whether legal or
illegal, have the potential to get into the environment, and living
organisms have a potential to be exposed," Daughton said.

Daughton, who was interested in environmental ramifications, realized
that the data could help law enforcement, sociologists and others
trying to gauge trends in drug abuse.

Most of those experts rely on door-to-door annual surveys, which are
based on questioning of 70,000 people nationwide. From those surveys,
they estimate that more than 20 million Americans used illicit drugs in 2006.

Scientists in Italy, led by Roberto Fanelli and Ettore Zuccato, were
the first to implement his idea, testing sewage in Milan, London and
Lugano, Switzerland, in 2005.

Amphetamines, including ecstasy, were the least prevalent drugs in
the three cities, while marijuana was detected widely, reported the
Mario Negri Institute for Pharmacological Research in the online
version of the journal Environmental Health Perspectives last month.

For every 1,000 people, about 210 milligrams of heroin were used
daily in London, compared with 70 in Milan and 100 in Lugano.
Amphetamine use also was higher in London.

The scientists were even able to use sewage to estimate individual
use and weekly trends. For instance, they estimated that people in
Milan used twice as much cocaine, about 35 grams per person per year,
than Italy's government surveys had suggested.

Cocaine use peaked on Saturdays, while heroin and marijuana use
remained steady weeklong.

In the United States, officials at the White House's Office of
National Drug Control Policy looked for cocaine in sewage from 24
regions in 2006.

Tests have shown that some U.S. cities have a bigger methamphetamine
problem than Europe. Within the U.S., Las Vegas' concentrations were
five times higher than Omaha's and twice Oklahoma City's, said Field,
who conducted those tests.

Comparing cities can be tricky. Concentrations can fluctuate due to
volumes of flow, the time of day and how long waste travels through
sewers, which gives drugs a chance to degrade.

"This has caught on only recently, and people are still trying to
understand the uncertainties," said Field, who is analyzing data from
96 locations in Oregon.

Jennifer de Vallance, spokeswoman for the White House's Office of
National Drug Control Policy, said the testing of sewage in 2006 was
an experiment to see if it could provide useful data to federal drug
officials at a low cost.

"It came back very favorable. Our determination was that it probably
could be done on a larger scale," she said.

EPA Assistant Administrator Benjamin Grumbles said the EPA and the
national drug office are "working on the details" of a voluntary
program at sewage plants that will test for illicit drugs.

"This is sensitive for various communities because these substances
do have a stigma attached to them," Daughton said. San Diego, for
example, refused to grant permission to researchers.

Some researchers are checking the environment for illicit drugs.
Traces of prescription drugs have been detected in some drinking
water supplies, while cocaine and other drugs have been found in
rivers. No one has tested drinking water for illicit drugs.

"Since most of these residues still have potent pharmacological
activities, their presence in the aquatic environment may have
potential implications for human health and wildlife," the scientists
from Milan reported in February.

Although few researchers are studying the effect of these ultra-low
doses, scientists say the threat to people is probably minimal. To
get a typical dose of cocaine, someone would have to drink 1,000
liters of raw sewage, Field said.

For now, this new drug test remains anonymous. Wastewater from
thousands, sometimes millions, of people is pooled at treatment
plants, so it cannot be tracked to any individual or specific location.

But because waste also can be tested in local sewers, questions about
privacy have been raised.

"You could take this down to a community, a street, even a house,"
Daughton said. "You can do all kinds of stuff with this. It's sort of
unlimited."