Wastewater data suggests meth use is at a record high. Here’s why we don’t need to panic

Data from Australia’s wastewater drug monitoring program suggests methamphetamine use (also known as speed, ice or crystal meth) is at a record high. Cocaine is also up. MDMA may be levelling off. Heroin is fluctuating.

At first glance, these findings from the Australian Criminal Intelligence Commission this week sound alarming.

But before we draw big conclusions about worsening drug use, it’s worth taking a closer look at what this data can and can’t tell us.

What wastewater data actually measures

Wastewater testing works by analysing sewage for traces of drugs people have used. Researchers test samples from treatment plants to estimate how much of a drug has been consumed by the population connected to that system.

It measures metabolised drugs. So it’s able to tell the difference between drugs that have been flushed down the toilet and drugs that have been excreted.

It’s a clever method that avoids some of the issues of self-report surveys, where people may under-report illegal behaviour.

It also gives close to real-time data unlike population surveys that are only conducted every few years.

But wastewater data can only measure the volume of drugs consumed, not the number of people using them or level of harm they experience.

Wastewater data can’t differentiate quantity from frequency. When it shows increases in particular drugs, we don’t know whether there are more people using the drug, or if the same people are using more of the drug, or using it more often.

It also can’t identify whether changes are due to higher purity.

So when we hear methamphetamine use is at a “ten-year high”, it really means the total quantity detected is higher, not necessarily that more Australians are using methamphetamine, or that harms are increasing.

Do these findings match other data?

National surveys, treatment data, hospital presentations, police seizures and wastewater data all track different parts of the drug system at different time points. And they don’t always move in the same direction at the same time.

Long-running population survey data shows a decrease in the prevalence of methamphetamine use over the past 15 years. Other data shows harms have increased, such as more people needing treatment and more ambulance callouts for methamphetamine. We have also seen a shift toward more potent forms of the drug and more intensive use among a smaller group of people.

That pattern fits with wastewater increases.

The same caution applies to cocaine. Wastewater data shows a steady rise but we can’t tell whether this reflects increased use by people who already use cocaine, or an increase in new users.

Based on other data – including the National Drug Strategy Household Survey, which shows increases in people trying the drug – it’s likely to be both.

Could prescriptions be affecting the data?

One question that often comes up is whether increases in stimulant prescriptions, such as those used to treat attention-deficit hyperactivity disorder (ADHD), could be influencing wastewater results.

There has been a significant increase in prescription amphetamines such as short- and long-acting dexamphetamine for ADHD.

Wastewater can’t easily distinguish between illicit and prescribed amphetamines.

But the scale of increase seen in the volume of methamphetamine is unlikely to be explained by prescription use alone.

MDMA levelling off

The wastewater report suggests MDMA use may be levelling off after earlier peaks. This is consistent with what we know about drug markets.

MDMA tends to follow social patterns. It rises with nightlife and festival culture, and falls when those environments change. We saw a big drop during the pandemic when both access to both MDMA and to festivals was substantially reduced.

There were early signs it was on the increase again. The plateau may reflect a stabilising market after post-pandemic rebounds.

Heroin is different

Heroin shows a more even pattern. Less than 1% of the population uses heroin but they tend to use it regularly, over a longer period.

Fluctuations in heroin use tend to occur when there are changes in supply, purity, or availability of treatments such as opioid substitution therapy, such as methadone.

Read more: How does methadone work as a heroin-replacement therapy? And what about the longer-acting buprenorphine?

What about the high rates in regional areas?

The wastewater report notes higher per capita use of some drugs in regional areas. But population survey data shows a lower percentage of people use illicit drugs in regional areas.

Wastewater data can make regional drug use look higher, not because more people are using drugs, but because a smaller group may be using them more heavily and more often.

Regional communities have fewer treatment services, greater economic stress and tighter social networks that can amplify both supply and harm.

Wastewater data also can’t tell who are visitors to an area and who are residents. Areas with festivals, for example, may show increases during festival season.

So wastewater data cannot be interpreted in isolation; it needs to be read alongside the many other robust data Australia collects.

A resilient and adaptive market

One of the clearest insights from the wastewater data is not about consumption, but about how resilient the drug markets are.

Despite an enormous amount of money and effort spent by law enforcement, markets continue to adapt and, in some cases, grow.

With high prices and strong demand, Australia remains an attractive market. So when one route is disrupted, another often emerges.

Rather than just focusing on reducing supply, policy responses should also prioritise reducing harm.

Patterns of use are becoming more concentrated. A smaller group of people seem to be experiencing more severe problems. These people need earlier and more targeted treatment and support to reduce harm.

In the end, it’s not just about how much drug is being used, it’s about what that means for the people using it.

If you’re worried about your own or someone else’s drug use, you can call the National Alcohol and other Drug Hotline on 1800 250 015.