Spatial differences and temporal changes in illicit drug use in <scp>E</scp>urope quantified by wastewater analysis

TLDR

The study aims to use wastewater analysis to map spatial and temporal patterns of illicit drug use across a large European population. Researchers collected one‑week raw wastewater samples from 25–47 treatment plants across 11–21 European countries in 2012–2013 and quantified excretion products of cocaine, amphetamine, ecstasy, methamphetamine, and cannabis using liquid chromatography‑mass spectrometry. Spatial patterns of illicit drug use varied widely across European cities, and while most drug levels remained stable over time, methamphetamine showed a notable decline in 2012; overall, wastewater data largely matched traditional surveillance and offers a faster, more comprehensive monitoring tool.

Abstract

Abstract Aims To perform wastewater analyses to assess spatial differences and temporal changes of illicit drug use in a large E uropean population. Design Analyses of raw wastewater over a 1‐week period in 2012 and 2013. Setting and Participants Catchment areas of wastewater treatment plants ( WWTP s) across E urope, as follows: 2012: 25 WWTP s in 11 countries (23 cities, total population 11.50 million); 2013: 47 WWTP s in 21 countries (42 cities, total population 24.74 million). Measurements Excretion products of five illicit drugs (cocaine, amphetamine, ecstasy, methamphetamine, cannabis) were quantified in wastewater samples using methods based on liquid chromatography coupled to mass spectrometry. Findings Spatial differences were assessed and confirmed to vary greatly across E uropean metropolitan areas. In general, results were in agreement with traditional surveillance data, where available. While temporal changes were substantial in individual cities and years ( P ranging from insignificant to &lt;10 −3 ), overall means were relatively stable. The overall mean of methamphetamine was an exception (apparent decline in 2012), as it was influenced mainly by four cities. Conclusions Wastewater analysis performed across Europe provides complementary evidence on illicit drug consumption and generally concurs with traditional surveillance data. Wastewater analysis can measure total illicit drug use more quickly and regularly than is the current norm for national surveys, and creates estimates where such data does not exist.