Wouldn't it be interesting to know if your neighbors are taking illegal drugs? Though it's not feasible to pinpoint exactly who is doing them, it is possible to detect trends in communitywide drug use with a new, simpler test that samples a teaspoon of wastewater.
Two researchers from the Pacific Northwest have simplified a procedure that, in effect, is a urinalysis for an entire community. The test's main goal is to determine how the environment is being contaminated by pharmaceuticals that are flushed down toilets and throughout sewers. But law enforcement and public health officials also might find a new stream of data they can use to fight emerging drug problems.
The wastewater test could be used to identify drug-use trends, such as the prevalence of methamphetamine, which has been a source of angst for law enforcement in parts of the Northwest and the rest of the United States.
"What we used to see with methamphetamine labs was, for many years, the number of labs were increasing," said Caleb Banta-Green, a researcher with the Alcohol and Drug Abuse Institute at the University of Washington. "Now, they're declining. I was doing mapping, and I could see that as numbers declined, [meth labs] were getting pushed from urban to rural areas. That's a perfect example of a phenomenon relevant for law enforcement."
Banta-Green was one of the researchers involved in developing the new procedure, which simplifies the task of spotting drugs in wastewater.
Medford, Ore., Police Chief Randy Schoen said his department hasn't discovered a meth lab in two years since the state passed a law requiring customers to register and present ID to buy over-the-counter medications, like Sudafed, that are used in the manufacturing of meth. "We would be interested in the results of the meth chemicals in the water as that would possibly alert us of meth labs that may be operating in our area," Schoen said.
Wastewater treatment plants are tested regularly to maintain functionality and to assure they comply with state and federal discharge requirements. They are tested for pH, residual chlorine and biological oxygen - but not drugs. Plants must report on how well they are functioning, but they typically aren't required to report on the presence of pharmaceuticals.
The new wastewater drug test streamlines existing ones; it's cheaper and speedier. The typical testing method - tandem mass spectrometry - identifies the unique products of various drugs by determining their molecular weight. It requires, however, a time-consuming step to concentrate the samples. Banta-Green and Jennifer Field, a professor of environmental and molecular toxicology at Oregon State University, eliminated that step and streamlined the process.
"[Treatment plants] take a number of small samples over a 24-hour period and put them into a single container, and then a subset is tested for the things they usually monitor," Field said. "We ask for a portion of that, and that's brought into a lab and analyzed. What our methodology does is quantify and produce a concentration of each drug, metabolite or biomarker in the whole water sample."
A biomarker is a substance in the water - one example is caffeine - to which the measurement of drugs, such as meth and cocaine, can be compared. Caffeine, probably found in the wastewater of every community, is considered an accurate biomarker to other drugs.
The researchers multiply the drug concentration numbers found in the wastewater by the total flow of the plant, which yields a calculation that is the total mass of the drug coming from the community. "You can then divide by either the stated population or some other biomarker of population," Field said. "You get a per capita, equivalent drug excretion for that municipality."
Field said there were a few surprises in what she and Banta-Green found in the water the first time they used their new process to test a local community. "What surprises me could simply be a function of my naivete," Field said. "For example, there are enough users excreting enough drugs that it's measurable."
She also was surprised to get queries about the confidentiality of the test: There's no way to pinpoint who is using drugs and who isn't because the sewer is a public commons. Everybody uses it. Field said the drugs found in the water were the "usual suspects," including cocaine, LSD, heroin and meth.
The new test method could be used to track drug excretion rates over time to spot trends that may be applied to drug intervention policies, Field said. "I see a lot of interest in individual communities to simply know if they have a drug issue that you can see in their [wastewater]."
The method could be used as an early warning system for the presence of drug problems within a community, according to Banta-Green. There's typically a lag of five to 10 years between the time an individual starts using drugs and the time he or she gets treatment. Mortality is obviously another indicator with a long lag time. "With this [wastewater test], theoretically, there's not a lag," said Banta-Green. "We're talking about a 24-hour lag, not a five-to-10-year lag."
The new test could give law enforcement a head start on addressing drug problems, enabling agencies to allocate resources before problems get out of hand, Banta-Green said. "This would give law enforcement the data to go to captains or chiefs and say, 'Not only do we think we're seeing drugs, we're hearing about it and it's in the water.'"
The test, however, cannot tell exactly how many people are using drugs and who they are, Banta-Green said. "We're really talking about a community load of a drug, and not how many people it is."
But there is some correlation between the load and heavy use by a community. If the test indicates a large load of meth in the wastewater, that's a good indicator of substantial use. "It's crude in terms of trying to quantify the number of people," Banta-Green said.
The utility of the test is being able to track drug-use changes over time and how it moves within a region, he said. "If it's getting done throughout the state, you can know geographically where it is, and if it's spreading."