Opinion

There has been a lot of interest in recent reports assessing alcohol and other drug (AOD) use levels utilising wastewater samples. But just what is wastewater analysis and what can it tell us?

The National Wastewater Drug Monitoring Program (NWDMP) is one of a number of AOD data collection systems. AOD data is collected for differing purposes and there is no definitive dataset that serves the needs of all interested parties (Roche, Pidd, Taylor & Freegard, 2011). Australia is fortunate to have a plethora of AOD-related data collections that all contribute to our understanding of the role that drugs and alcohol play in the health and wellbeing of individuals and communities (Roche, Pidd, Taylor & Freegard, 2011).

The NWDMP is designed to measure population-scale substance use and aims to establish baseline data on AOD use across Australia. It provides a measure of the demand for various licit and illicit drugs and specifically measures the presence of 12 drugs including alcohol, nicotine, methamphetamine, amphetamine, cocaine, heroin, MDMA, oxycodone and fentanyl. Cannabis is not tested for as part of the NWDMP (ACIC, 2018).

On 4 March 2018, the Australian Criminal Intelligence Commission (ACIC) released its fourth NWDMP report (in a series of nine) of licit and illicit drug use from 45 wastewater sites (20 capital city and 25 regional sites) across Australia. Wastewater samples were collected in October and December 2017 and analysed at the University of South Australia and University of Queensland (ACIC, 2018).

Although the NWDMP is administered by a law enforcement agency and is funded through the Confiscated Assets Fund, it is not used by law enforcement agencies as an intelligence-gathering tool to target individuals. It has both law enforcement and health applications, and from a health perspective, the NWDMP data can be used, in conjunction with other data, to inform AOD prevention and treatment programs.

The release of the March 2018 report prompted heightened media interest with headlines such as:

• Calls for more treatment services as Adelaide retains title of 'ice capital of Australia' 
• Sewage reveals Aussies’ huge drug problem
• Use of ‘hillbilly heroin’ high in Tasmania
• This test proves we’re using more meth
• Report finds cocaine use rising in regional areas

However, a key finding under-reported by the media was that while the NWDMP found that methamphetamine was the highest consumed illicit drug, alcohol and nicotine were consistently the highest consumed drugs in all states and territories (ACIC, 2018).

The report also found that levels of heroin consumption were generally lower than pharmaceutical opioids such as fentanyl and oxycodone. Importantly, the per-capita average regional consumption of fentanyl and oxycodone exceeded consumption levels in the capital city sites (ACIC, 2018).

What is wastewater analysis really telling us from an AOD policy and service provision perspective and how can we use the data to inform evidence-based practice?

By way of background, internationally, wastewater analysis commenced in Italy in 2004 and has been used in Australia in Queensland since 2009 and in South Australia since 2011 (Irvine, Kostakis, Felgate, Jaehne, Chen & White, 2011). In 2016, it was expanded to include sites in other Australian jurisdictions with the allocation of monies from the Confiscated Assets Fund (ACIC, 2017).

The wastewater collection methods and analysis protocols used by Australian jurisdictions are similar to their overseas counterparts thereby allowing for jurisdictional, national and international comparisons (ACIC, 2018).

A recent review by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) of wastewater-based epidemiology concluded that:

• No single measure of AOD use provides a complete picture of patterns and prevalence
• National surveys can be time-consuming and complex with significant intervals between data collection
• Wastewater analysis allows for non-invasive and near real-time analyses and can act as an early warning system for spikes in the use of drugs under examination
• Wastewater analysis is not subject to the biases associated with self-reported data (EMCDDA, 2016).

Nevertheless, wastewater testing has its limitations and may not necessarily provide a comprehensive indication of overall patterns of drug use. For example, recent increases in levels of methamphetamine found in wastewater could stem from a larger number of people using small amounts or a relatively small number of people using larger amounts of the drug . In addition, the wastewater analyses cannot be broken down by more fine-grained demographic consumer variables (eg age, gender and ethnicity).

Different data sets can sometimes appear inconsistent. For example, the 2016 National Drug Strategy Household Survey (NDSHS) data shows that nationally there was a significant decrease in overall recent meth/amphetamine use between 2013 and 2016 (from 2.1% to 1.4%) (AIHW, 2017).

Conversely, the NWDMP data found consistently high levels of methamphetamine between August 2016 and December 2017 albeit with significant jurisdictional and regional differences (ACIC, 2017). Examination of the wastewater historical data shows that, for most jurisdictions, between 2013 and 2016 there was no evident decline in methamphetamine use (ACIC, 2017).

In addition, the recently published key findings from the 2016-17 Alcohol and Other Drug Treatment Services National Minimum Data Set (AODTS NMDS) show that the proportion of closed treatment episodes for clients receiving treatment for amphetamines has more than doubled in 10 years, from 11% in 2007–08 to 27% in 2016–17. The demand for methamphetamine-related treatment services is therefore high and services are seeing more people experiencing problems associated with their use of crystal methamphetamine (AIHW, 2018).

So what are we to make of this apparent paradox?

The NDSHS provides a global overview of the characteristics of individual AOD consumers but, as a result of its data collection methods, is likely to provide conservative estimates of levels of use.

The NWDMP, which reports its findings every 3-4 months provides accurate and recent information on the:

• Quantum of drugs in communities 
• Demand for a range of licit and illicit drugs
• Different consumption patterns across jurisdictions and regions.

However, it provides limited insight into specific patterns of use or the characteristics of users.

Synthesising findings from all data sources can provide policy makers with a more accurate picture of how much AOD is being used, patterns of use, characteristics of users and the nature of harms experienced.

Each of Australia’s AOD-related data collections, including the NWDMP, provide their own unique insights and need to be considered collectively as part of the broader context of available evidence. When examined as a whole they offer an important picture of drug markets and AOD use in Australia and yield evidence-based information to inform law enforcement and health-based policy and service responses.

References

Australian Criminal Intelligence Commission (ACIC) (2018). National Wastewater Drug Monitoring Program – Report 4, March 2018 https://www.acic.gov.au/sites/g/files/net3726/f/nwdmp4.pdf?v=1522809564

Australian Criminal Intelligence Commission (ACIC) (2017). National Wastewater Drug Monitoring Program – Report 1, March 2017 https://www.acic.gov.au/sites/g/files/net1491/f/national_wastewater_drug...

Australian Institute of Health and Welfare (AIHW) (2017). National Drug Strategy Household Survey 2016: detailed findings. Drug Statistics series no.31. Cat.no. PHE 214. Canberra: AIHW.

Australian Institute of Health and Welfare (AIHW) (2018). Alcohol and other drug treatment services in Australia 2016-17: key findings. Canberra: AIHW https://www.aihw.gov.au/reports/alcohol-other-drug-treatment-services/ao...

European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) (2016). Assessing illicit drugs in wastewater: advances in wastewater-based drug epidemiology. Insights 22, Publications Office of the European Union, Luxembourg.

Irvine, R.J., Kostakis, C., Felgate, P., Jaehne, E.J., Chen, C., & White, J. (2011). Population drug use in Australia: A wastewater analysis. Forensic Science International, 210 (1-3), 69-73.

Roche, A.M., Pidd, K., Taylor, C., & Freegard, S. (2011). Australia’s key alcohol-related datasets. National Centre for Education and Training on Addiction (NCETA), Flinders University, Adelaide South Australia.