Methamphetamine abusers could someday be one flush away from arrest.
Scientists have tested a device that can detect meth in sewage lines near places of suspected meth use or manufacture. The successful test of the Polar Organic Chemical Integrative Sampler (POCIS) by Tennessee Technological University researchers demonstrates a new way that law enforcement might be able to zero in on illicit drug cookers.
The three locations studied in Cookeville, Tenn., were among those already published in the local newspaper as places where meth busts had occurred, explained Tennessee Tech environmental chemist Tammy Boles. The POCIS was placed directly in the raw sewage for four weeks to collect any possible methamphetamine coming out of a nearby lines from the buildings. Meth was found in sewage from one of three sampling sites at a significant concentration, reported Boles and Martha J.M. Wells in their paper in the Feb. 15 issue of the journal Science of the Total Environment.
The POCIS device works by having an absorbent material sandwiched between two membranes which let water and dissolved chemicals pass through it. The absorbent traps and collects chemicals. When the POCIS is pulled out of the waste water, the absorbent layer is analyzed in a lab to discover what chemicals it has gathered during its time underwater.
Boles cautioned that the meth they detected in the Cookeville sewage could have been from either manufacture or from the urine of meth users – since meth passes through the human body chemically intact. So intact, she said, that some meth labs have been found filled with jugs of urine from meth users intending to recycle the drug.
"It's crazy that people do to make this," said Boles, whose study was funded by the U.S. Department of Justice.
Bole's paper is the first to demonstrate how the POCIS device could be useful to law enforcement in locating and closing down clandestine meth labs.
"The paper showed a proof of concept that it is possible to qualitatively determine either presence, or absence, of a polar compound of interest in raw sewage," said research chemist Tammy Jones-Lepp of the U.S. Environmental Protection Agency.
The POCIS approach contrasts with grab sampling of sewage waters, she explained, which only shows what's in waste water for a brief moment. "Whereas, with POCIS the deployments can last for several days to weeks, giving a more holistic understanding of any emerging contaminants present over a longer period of time."
Boles is careful to point out that the new technique could pose ethical issues, especially with regards to privacy, and so they were careful to put the POCIS devices only in city-owned waste water lines. Their goal in this prove the technique would work, not actually indict anyone at this time. "We don't want to identify where we found it," she said. "That's not our goal."
The work also has implications for waste water treatment plants, which are charged with cleaning waters despite the fact that they often don't know what compounds -- like meth or pharmaceuticals -- is in waste water.
"Sampling, and the reporting of emerging contaminants, such as pharmaceuticals, has been on-going in the U.S. for over 10 years and longer in the EU," said Jones-Lepp. Some water authorities in the United States have been using both grab sampling and POCIS samplers already to get a better handle on what's entering their waste streams and water supplies.
"I could see this new research development as a tool to in helping water authorities better understand which areas of a municipality input different waste streams into a wastewater treatment plant, and maybe through the use of new engineering techniques remove emerging contaminants that are problematic before they enter into the wastewater treatment plant."
As for the meth that's entering waste water treatment plants, it's not treated, said Boles. It could even up in lakes and streams of Tennessee, just like it has already been measured in surface waters in Europe, she said.
"It's just amazing what's in our waste water after treatment," said Boles. "We can't really effectively clean them up and we have a finite amount of water."