Drug use tracked through waste water monitoring

Drug enforcement is going down the toilet. Illegal drug use can be monitored by tracing drug concentrations in sewage water.

A method to do so was outlined in a new research paper by Kevin Bisceglia and Lynn Roberts, of Hopkins Environmental Engineering Department, in collaboration with the National Institute of Standards ad Technology (NIST) in the journal Analytical and Bioanalytical Chemistry.

The use of illicit drugs in a society is difficult to track using traditional methods. Data is collected primarily in two ways.

First is emergency room screenings, which see a high percentage of heavy users. Second are random and anonymous telephone surveys, which depend on the honesty of those being asked. A more rigorous methodology needs to be employed to get more accurate data.

When a person uses drugs, both legal and illegal, evidence of such consumption can be found in urine. In a city, all toilet water is routed through the sewage system, passing through a wastewater treatment plant. Samples of this water can then be collected and analyzed for drug concentrations.

“By monitoring this waste stream, it may be possible to conduct drug tests on entire cities, or possibly on smaller geographic regions within cities,” Bisceglia  wrote in an email to The News-Letter. “The advantage of this approach over [others] is that it is likely to be cheaper and more accurate. It might also be possible to perform this wastewater-based monitoring in near ‘real time,’ so that municipalities can evaluate whether their approaches for the treatment and control of drug abuse are effective, and modify them accordingly.”

Sewer epidemiology, as the field is known, has been attempted in various European cities as well as by one other American group.

Expanding on this work, Bisceglia developed a method that employs a technique called liquid chromatography-tandem mass spectrometry (LC-MS/MS) to measure drug concentrations in levels of parts per trillion.

The method allows for detection of cocaine and 13 metabolites, as well as methamphetamine, amphetamines, ecstasy, oxycodone (oxycontin) and hydrocodone (vicodin) — all simultaneously.

“The method is notable because its expanded suite of cocaine metabolites greatly reduces the uncertainty associated with resulting estimates of cocaine consumption, and may also allow us to distinguish between cocaine that is smoked as crack-cocaine, and cocaine consumed by other means,” wrote Bisceglia.

The researchers aim for the method to be adopted by cities as an alternative to more qualitative studies. Therefore, the goal is for it “to be reliable and robust.” If successful, this way would save money while also being more accurate.

Testing was carried out at the Back River Wastewater Treatment Plant in Baltimore in April 2009; the plant serves approximately 944,000 people.

“Our purpose was not to rigorously evaluate drug consumption in Baltimore, but rather to test our method,” wrote Bisceglia.

Nevertheless, data was collected on cocaine consumption in Baltimore. “We estimated that about 3 kilograms of cocaine was consumed in a day. This number was higher than what has been estimated in European cities (estimations performed by other researchers), but is not the highest reported estimation for a city in the US.”