Sewage Tells Tales about Community-Wide Drug Abuse

Newswise — Public health officials may soon be able to flush out more accurate estimates on illegal drug use in communities across the country thanks to screening test described here today at the 234th national meeting of the American Chemical Society, the world's largest scientific society. The test doesn't screen people, it seeks out evidence of illicit drug abuse in drug residues and metabolites excreted in urine and flushed toward municipal sewage treatment plants.

The approach could provide a fast, reliable and inexpensive way to track trends in drug use at the local, regional or state levels while preserving the anonymity of individuals, says lead researcher Jennifer Field, Ph.D., an environmental chemist at Oregon State University who works with colleagues at Oregon State University and at the University of Washington.

Past estimates of illicit drug abuse in a community were based largely on surveys in which children and adults were asked about their use of illegal drugs. Researchers knew that some were untruthful, with individuals reluctant to admit breaking the law.

Preliminary tests conducted in 10 U.S. cities show the method can simultaneously quantify methamphetamine and metabolites of cocaine and marijuana and legal drugs such as methadone, oxycodone, and ephedrine, according to Aurea Chiaia, a graduate student who is working to refine the process and described details at the ACS meeting.

"Because our method can provide data in real time, we anticipate it might be used to help law officials undertaking surveillance to make intervention or prevention decisions or to decide where to allocate resources," Chiaia says.

Recently, scientists have sought ways to gauge illegal drug use by measuring the levels of drugs and their by-products found in rivers and wastewater. Last year, Italian scientists found ways to detect metabolites for cocaine in the Po River, giving law enforcement officials more accurate estimates on cocaine use in the area. The U.S. Office of National Drug Control Policy has obtained samples from a dozen different waterways in an effort to assess illegal drug use, as well.

Field says the new screening method under development in her lab improves upon the utility of the laboratory tools currently used to identify traces and metabolites of drugs in such studies. Tandem mass spectrometry, for example, is a laboratory method routinely used to identify the unique by-products of various drugs by determining their molecular weight. The problem is, the method frequently requires a time-consuming off-line process to concentrate the samples.

Field and her colleagues have eliminated that step. "By streamlining this process, we can cut back on the use of solvents and bring about a savings in time, therefore saving money," Field says.

Her lab is now refining the technique to verify its accuracy for extremely low concentrations, on the order of a few nanograms (billionths of a gram) per liter. Calculations of drug use based solely on byproducts found in water supplies, especially at low levels, can be subject to error, Field says. To address this issue, her lab is working to identify common indicators, or biomarkers, such as caffeine or nicotine that can be used to sharpen their calculations.

"A lot of things contribute to the flow in wastewater, including agricultural and industrial processes," Field says. "By linking our illicit drug measurements to biomarkers related to measurable human activities, we could compensate for differences in flows that aren't related to human excretion."

The method would eliminate the need to rely on surveys, medical records and crime reports to assess the scope of a community's drug abuse problem, she says, and allow drug enforcement officials to monitor drug use through time and across geographic regions.

"If you're looking for trends over time or space, this will be a suitable methodology," she says. "By using rapid screening methods on a regular basis, we could follow regional (spatial) trends over time in drug use," she says.

Collaborating with Field and Chiaia are Daniel Sudakin, Ph.D., associate professor of environmental and molecular toxicology at Oregon State University and Caleb Banta-Green, M.S., a research scientist at the University of Washington's Alcohol and Drug Abuse Institute.

The American Chemical Society — the world's largest scientific society — is a nonprofit organization chartered by the U.S. Congress and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio.

— Susan Gaidos

The paper on this research, ENVR 080, will be presented at 2:25 p.m. Tuesday, Aug. 21, at the Boston Park Plaza, Stanbro Room, during the symposium, "Symposium Honoring Dr. Walter Giger: Emerging Contaminants."

Jennifer Field, Ph.D., is a professor with the Department of Environmental and Molecular Toxicology at Oregon State University, in Corvallis, Oregon.

Aurea Chiaia is a master's student in the Chemistry Department at Oregon State University.

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ALL PAPERS ARE EMBARGOED UNTIL DATE AND TIME OF PRESENTATION, UNLESS OTHERWISE NOTED

The paper on this research, ENVR 080, will be presented at 2:25 PM, Tuesday, 21 August 2007, during the symposium, "Symposium Honoring Dr. Walter Giger."

ENVR 080Determination of illicit drugs and biomarkers in raw municipal wastewater influent as a tool for drug epidemiology

Program Selection: Division of Environmental ChemistryTopic Selection: Symposium Honoring Dr. Walter Giger: Emerging Contaminants

Abstract

The synthesis and abuse of illicit drugs is a widespread public health problem. Current techniques in drug-use epidemiology are limited by time lags, poor geographic resolution, substantial under-reporting bias, and an over reliance on morbidity and mortality data. To address these limitations, we have initiated a program that links analytical measurements for illicit drugs, key metabolites and precursors with population indicators including residents served by sewer districts as well as human population biomarkers. A sensitive and selective analytical method based on large-volume injection and liquid chromatography/tandem mass spectrometry was developed to quantify abuse drugs and human biomarkers in raw sewage influents with a goal of obtaining high throughput and accuracy. Illicit drugs, metabolites, and precursor concentrations measured in 24 hr flow-normalized composites of raw influents from municipal wastewater treatment plants are normalized against population indicators for use as a low-cost tool to estimate community burdens of illicit drugs.

Researcher Provided Non-Technical Summary

Briefly explain in lay language what you have done, why it is significant and what are its implications (particularly to the general public)

Determination of illicit dugs and biomarkers in raw municipal wastewater influent as a tool for drug epidemiology

Drug abuse is a widespread public health problem but there are several limitations to the current methods for documenting and anticipating the distribution of illicit drugs over time and across regions of the country. For example, documenting the occurrence and spread of drug abuse in large populations and across large regions is limited by a substantial under-reporting bias, which often relies on self-reporting by drug abusers, and an over dependence on police, poisoning, or death reports. To address these limitations, we have initiated a program that uses analytical measurements of illicit drugs in primary wastewaters of municipalities as a low-cost tool to estimate community consumption of illicit drugs. Illicit drugs like cocaine, methamphetamine, heroin and their forms that result from being metabolized in the body are measured in composite samples of raw influent collected from municipal wastewater treatment plants. In addition to the stated population served by a wastewater treatment plant, we are using population indicators or biomarkers like nicotine, for which sales are widely known, and creatinine, a breakdown body product excreted from humans, to be used as human population indicators to normalize measured concentrations of illicit drugs as an alternative to estimate per capita or 'community burdens' of illicit drugs. The approach developed for this study is designed to provide local health and social services information on trends in illicit drug use over time for their communities and to provide information on changes in illicit drug use on a regional scale in order to help them allocate resources (law enforcement and funds for prevention and intervention) and to monitor the outcomes of their efforts.

How new is this work and how does it differ from that of others who may be doing similar research?

The environmental impact and persistence of psychoactive drugs in different aquatic matrices is a field of recent research (1, 2). Drugs of abuse and metabolites in river water had been applied as a tool to surveillance community drug consumption (3, 4). Laboratories conventionally use gas chromatography-mass spectrometry (GC-MS) for the analysis of drugs, but this procedure is time consuming and usually needs derivatization. A sensitive and selective rapid analytical method based on large-volume injection and liquid chromatography/tandem mass spectrometry was developed to normalize data with human indicators, provide per capita consumption and establish a correlation between abuse drugs at the community, regional, or state to drug poisoning incidents reported statewide to Poison Control Centers to be used as a low-cost tool to estimate community burdens of illicit drugs.

References:(1) Hummel, D.; Loffler, D.; Fink, G.; Ternes, T. A. Environ. Sci. Technol. 2006, 40, 7321-7328.(2) Ternes, T. A.; Meisenheimer, M.; McDowell, D.; Sacher, F.; Brauch, H. J.; Haist-Gulde, B.; Preuss, G.; Wilme, U.; Zulei-Seibert, N. Environ. Sci. Technol. 2002, 36, 3855-3863.(3) Zuccato, E.; Chiabrando, C.; Castiglioni, S.; Calamari, D.; Bagnati, R.; Schiarea, S.; Fanelli, R. Environmental Health: A Global Access Science Source 2005, 4, 14.(4) Castiglioni Sara, Z. E., Crisci Elisabetta , Chiabrando Chiara , Fanelli Roberto , and Bagnati Renzo Analytical Chemistry 2006, 78 8421 -8429.