Spatio‐temporal assessment of illicit drug use at large scale: evidence from 7 years of international wastewater monitoring
Authors: González‐Mariño Iria , Baz‐Lomba Jose Antonio , Alygizakis Nikiforos A. , Andrés‐Costa Maria Jesús , Bade Richard , Bannwarth Anne , Barron Leon P. , Been Frederic , Benaglia Lisa , Berset Jean‐Daniel , Bijlsma Lubertus , Bodík Igor , Brenner Asher , Brock Andreas L. , Burgard Daniel A. , Castrignanò Erika , Celma Alberto , Christophoridis Christophoros E. , Covaci Adrian , Delémont Olivier , de Voogt Pim , Devault Damien A. , Dias Mário J. , Emke Erik , Esseiva Pierre , Fatta‐Kassinos Despo , Fedorova Ganna , Fytianos Konstantinos , Gerber Cobus , Grabic Roman , Gracia‐Lor Emma , Grüner Stefan , Gunnar Teemu , Hapeshi Evroula , Heath Ester , Helm Björn , Hernández Félix , Kankaanpaa Aino , Karolak Sara , Kasprzyk‐Hordern Barbara , Krizman‐Matasic Ivona , Lai Foon Yin , Lechowicz Wojciech , Lopes Alvaro , López de Alda Miren , López‐García Ester , Löve Arndís S. C. , Mastroianni Nicola , McEneff Gillian L. , Montes Rosa , Munro Kelly , Nefau Thomas , Oberacher Herbert , O'Brien Jake W. , Oertel Reinhard , Olafsdottir Kristin , Picó Yolanda , Plósz Benedek G. , Polesel Fabio , Postigo Cristina , Quintana José Benito , Ramin Pedram , Reid Malcolm J. , Rice Jack , Rodil Rosario , Salgueiro‐González Noelia , Schubert Sara , Senta Ivan , Simões Susana M. , Sremacki Maja M. , Styszko Katarzyna , Terzic Senka , Thomaidis Nikolaos S. , Thomas Kevin V. , Tscharke Ben J. , Udrisard Robin , van Nuijs Alexander L. N. , Yargeau Viviane , Zuccato Ettore , Castiglioni Sara , Ort Christoph 
Published: October 2019

Background and aims

Wastewater‐based epidemiology is an additional indicator of drug use that is gaining reliability to complement the current established panel of indicators. The aims of this study were to: (i) assess spatial and temporal trends of population‐normalized mass loads of benzoylecgonine, amphetamine, methamphetamine and 3,4‐methylenedioxymethamphetamine (MDMA) in raw wastewater over 7 years (2011–17); (ii) address overall drug use by estimating the average number of combined doses consumed per day in each city; and (iii) compare these with existing prevalence and seizure data.

Design

Analysis of daily raw wastewater composite samples collected over 1 week per year from 2011 to 2017.

Setting and Participants

Catchment areas of 143 wastewater treatment plants in 120 cities in 37 countries.

Measurements

Parent substances (amphetamine, methamphetamine and MDMA) and the metabolites of cocaine (benzoylecgonine) and of Δ9‐tetrahydrocannabinol (11‐nor‐9‐carboxy‐Δ9‐tetrahydrocannabinol) were measured in wastewater using liquid chromatography–tandem mass spectrometry. Daily mass loads (mg/day) were normalized to catchment population (mg/1000 people/day) and converted to the number of combined doses consumed per day. Spatial differences were assessed world‐wide, and temporal trends were discerned at European level by comparing 2011–13 drug loads versus 2014–17 loads.

Findings

Benzoylecgonine was the stimulant metabolite detected at higher loads in southern and western Europe, and amphetamine, MDMA and methamphetamine in East and North–Central Europe. In other continents, methamphetamine showed the highest levels in the United States and Australia and benzoylecgonine in South America. During the reporting period, benzoylecgonine loads increased in general across Europe, amphetamine and methamphetamine levels fluctuated and MDMA underwent an intermittent upsurge.

Conclusions

The analysis of wastewater to quantify drug loads provides near real‐time drug use estimates that globally correspond to prevalence and seizure data.