Wastewater-based epidemiology (WBE):

a new approach to monitor drug use and

emerging trends

EMCDDA Conference – 20 years of monitoring and communicating evidence on drugs

Lisbon, 21-22 September 2015

Sara Castiglioni Mario Negri Institute

Department of Environmental Health Sciences

Unity of Environmental Biomarkers

Rational of the approach

� Almost all substances we consume

are excreted unchanged or as a

mixture of metabolites in urine

and/faeces

� Excreted substances end up in sewer network

�Enter sewage treatment plants

Raw wastewater is containing all the metabolic

residues of substances consumed by a defined

population

Raw wastewater contains multiple information

on human habits in a defined population

Wastewater-Based Epidemiology: Illicit Drugs

The route of the drugs: from the consumer to the STP

CONSUMPTION ESTIMATE

Amounts of the residues

(g/day) are used to back-

calculate drug consumption in

the population served by the

STP (g/day of the parent drug)

Illicit Drugs

-cocaine

-cannabis

-heroin

-amphetamines

CONSUMER

Excretes residues of

the drugs with urine

after the intake

TREATMENT PLANT

The residues of the drugs

are transported to the STP

with the wastewater

DRUG RESIDUES

QUANTIFICATION

Wastewater is sampled and

the residues of the drugs at

the STP are quantified

Wastewater-Based Epidemiology Approach

Mass spectrometric analyses

Concentrations of Target

Residues

Amount of target residues entering a

sewage treatment plant per day (g/day)

Daily flow

rate

Amounts of each parent substance

consumed by the population served by

the plant

Human

metabolism

Collection of raw wastewater

samplesComposite 24 h samples

Ability to provide:

� Objective estimates

� Qualitative and quantitative evaluation

� Real-time estimates

� Updated information on substance use

� Possibility to identify changing habits and new substances

Novelty of the WBE Approach

WBE approach was proposed as a complementary

indicator of drug use

Objectives

Sewage analysis CORE group (SCORE) Activities

2010 8 European Research Institutes joined

and a European Collaboration started

� Organize the first Europe-wide monitoring

� Establish a common protocol

� Check the performance of analysis through an

interlaboratory study

Sewage analysis CORE group (SCORE) Activities

Europe-wide monitoring (2011-2015)Results available at:

http://www.emcdda.europa.eu/topics/pods/waste-water-analysis

Interlaboratory test (2011-2015) to check the quality of results

Each laboratory is required to analyze standards and samples spiked

at known levels and distributed by one lab – paper in preparation

Results from Europe-wide monitoring

LOADS mg/day/1000 people

1. How to improve data comparability ?

2. How results from WBE can be used to

integrate epidemiological data?

Sewage analysis CORE group (SCORE) Activities

Best practice protocol Guidelines addressing sampling,

storage and chemical analyses

Identification of gaps

and uncertainty

Minimize or control uncertainties

Suggestions for each step of WBE

New Insight publication on WBE by EMCDDA

Compare WBE with epidemiological data

Compare WBE with epidemiological data

Comparison among:

1. GPS survey

2. Wastewater analysis

3. Survey among drivers

Comparing consumption estimates

Data were compared as absolute quantities – total amount consumed

WBE Estimate of ConsumptionGPS data: number of users x

frequency of use

60-91 kg/year 70-165 kg/year

Comparing prevalence estimates

Data from WBE were transformed for comparison

WBE Estimates: Consumption/ per user consumption figure

GPS data

1.9% (1-4 %) 2.9% (2.6-3.2 %)

Reid et al., BMJ open, 2012

Compare WBE with epidemiological data

Population surveys compared with wastewater analysis for monitoring illicit drug consumption in Italy in 2010-2014

Ettore Zuccato, Sara Castiglioni, Ivan Senta, Andrea Borsotti,

Bruno Genetti, Alessandra Andreotti, Giovanni Pieretti,

Giovanni Serpelloni

Temporal trend of cocaine use in Milan

Spatial distribution of cocaine use in Italy

Prevalence data ( about 55% drop)

Last Month: 2.6% in 2007 - 1.2% in 2010

Last Year: 5% in 2007 - 2.1% in 2010(Source: Local Health Agency 2011)

Last Year: 2.1% in 2008 – 0.9% in 2010(GPS survey, Source: Department of Anti-Drug Policies, 2010)

45% drop

Temporal Trends in Milan - WBE approach Spatial distribution in Italy - WBE approach

Consumption measured in October 2011

Prevalence measured in January 2012

(last month prevalence)(GPS survey, Source: Department of Anti-Drug Policies, 2012)

Compare WBE with epidemiological data

Challenges and research needs:

�Comparison of similar estimates (collection of additional data)

� Size of sample populations

�Temporal inconsistencies

�Spatial inconsistencies :

- population is mobile

- lack of geographical correspondence between wastewater

catchment and surveyed areas

�Sampling strategy in WBE to produce reliable figures at different

geographical scales

WBE can’t act alone but provide supporting information

Collaboration with epidemiologists is essential

Wastewater-Based Epidemiology: Potential Uses

This method can provide

• Evidence-based and real-time estimates of drug collective consumption

It can be successfully employed to:

1. Estimate spatial differences at different scales (local, national, international)

2. Monitor temporal trends (daily, weekly, yearly)

3. Monitor consumption changes in specific sites (rural vs urban) or during special events (holidays or music events)

4. Assess drug use in specific populations (prisons, schools, sub-populations in a city)

5. Identify new substances (new psychoactive substances)

Temporal trends – Novel synthetic stimulants

Drug Use in Adelaide, Australia (Chen et al., Forensic Science International, 2013)

Monitoring of new synthetic recreational drugs

Ketamine is a

dissociative

anaesthetic drug...

...with documented

increase in its use

as a recreational drug

Increased use in Milan from 2008 to 2013

4-5 weeks investigated per year

Profile of KETAMINE use in Milan in a six-year study

Conclusions

� Wastewater - based epidemiology is a promising novel

indicator to measure drug use in a population

� The approach gives objective and updated information

� The approach has been refined by developing a

best practice protocol

� Several attempts were a done to compare data –

WBE versus epidemiological data

� Interdisciplinary collaboration is essential to improve

the methodologies and their comparison

Thanks

Thanks for your attention!

SCORE GroupSara Castiglioni

Lubertus Bijlsma, Adrian Covaci,

Erik EmkeFélix Hernández,

Malcolm Reid, Christoph Ort,

Kevin V Thomas, Alexander LN van Nuijs,

Pim de Voogt, Ettore Zuccato

EMCDDAPaul Griffith,

Jane Mounteney, Danica Thanki, Liesbeth Vandam

COST Action ES1307