The latest findings from the largest European project in the emerging science of wastewater analysis, presented by the Europe-wide SCORE group, in association with the EU drugs agency (EMCDDA), have found that while cocaine continues to be the most consumed narcotic in Portugal, ecstasy is becoming increasingly popular.
The project analysed wastewater in over 50 European cities in 18 European countries in March 2016, to explore the drug-taking behaviours of their inhabitants. Among the cities studied were Lisbon, Porto and Almada. The study analysed daily wastewater samples in the catchment areas of Wastewater Treatment Plants (WWTPs) over a one week period.
Wastewater from approximately 25 million people was analysed for traces of four illicit drugs: amphetamine, cocaine, MDMA (ecstasy) and methamphetamine. Wastewater-based epidemiology is a rapidly developing scientific discipline with the potential for monitoring near-real-time, population-level trends in illicit drug use.
Researchers were able to establish that traces of ecstasy almost doubled over weekends in Lisbon, Porto and Almada. Cocaine use remained relatively stable throughout the week, with the lowest consumption recorded on Wednesdays, while Saturdays were the peak. Scientists say they were able to estimate the quantity of drugs used in a community by measuring the levels of illicit drugs and their metabolites excreted in their urine.
While annual wastewater monitoring campaigns have been conducted since 2011, this is the first time that data has been published within only a few months of the campaign, underlining the potential of this method for the timely monitoring of trends in illicit drug use at population level. Traces of cocaine in wastewater indicate that cocaine use is highest in western and southern European cities, particularly in cities in Belgium, the Netherlands, Spain and the UK. The analysis points to very low to negligible cocaine use in the majority of eastern European cities.
For ecstasy, the 2016 wastewater data confirmed the trend established in 2015. In most cities, wastewater MDMA loads were higher in 2016 than in 2011, with sharp increases seen in some cities, which may be related to the increased purity of MDMA or increased availability and use of the drug.
The loads of amphetamine detected in wastewater varied considerably across the study locations, with the highest levels reported in cities in the north of Europe. Amphetamine was found at much lower levels in cities in the south of Europe. When weekly patterns of drug use were examined, cocaine and MDMA (ecstasy) levels rose sharply at weekends in most cities, while methamphetamine use appeared to be more evenly distributed throughout the week.
Commenting on the findings, EMCDDA Director Alexis Goosdeel said: “Wastewater-based epidemiology has demonstrated its potential to become a useful complement to established drug monitoring tools.” The EMCDDA chief added that its ability to deliver timely data on drug use patterns is particularly relevant against the backdrop of an ever-shifting drugs problem. “By detecting changes in drug use patterns, both geographically and over time, it can help health and treatment services respond better to emerging trends and changing treatment needs.” In 2017, on the margins of the Lisbon Addictions 2017 conference, the EMCDDA will also be co-hosting ‘Testing the waters 2017’, the third international conference on wastewater analysis.