Drug use in regional Australia is outpacing consumption in capital cities, according to new data.

Figures released by the Australian Criminal Intelligence Commission on Monday show that while Sydney is still the capital for cocaine, and heroin is most frequently found in Melbourne, it is in regional Australia where drug use is most pronounced.

The data – which analyses wastewater from sites across Australia – reveals that in regional Australia the average use of methamphetamine, oxycodone, fentanyl, MDMA, cannabis, alcohol and nicotine outstripped capital city consumption.

Now in its third year, the commission’s wastewater analysis shows how much of each drug is being consumed around the country, underlining the size of the market.

Perhaps most concerning for law enforcement, some drugs have been intercepted at a greater rate than others. While almost twice as much MDMA was seized as was used, heroin, cocaine and methamphetamine seizures remained at half or less-than half of consumption.

The commission’s chief executive, Michael Phelan, said the latest figures showed demand for drugs “has not gotten any better”.

“Australians have an insatiable demand for all sorts of narcotics and synthetic drugs,” Phelan told reporters in Brisbane.

The figures show that population-weighted average consumption of methamphetamine, cocaine, MDMA and heroin in capital city and regional areas all increased in the period measured.

Besides heroin use in regional areas, all of those drugs saw the highest consumption levels since measurement began. The data did, however, show an overall drop in the use of prescription opioids such as oxycodone and fentanyl, though in some areas, including Tasmania, the use of the former increased.

Sewage analysis cannot differentiate between neighbourhoods or suburbs, and the waste being sampled is a mix of that flowing from prisons, hospitals, offices, homes, hotels and shopping centres.

It also cannot distinguish between prescribed or illicit opioid use, or whether nicotine intake is from tobacco, e-cigarettes, patches or gum.

The commission aims to establish baseline data of substance use across Australia, claiming the latest data collection represents 55% of Australia’s population, or 12.9 million people.

Its results are used to inform government policy and decision making, as well as law enforcement activities.