Regional Australians more than doubled their use of the highly potent opioid fentanyl within a year, the latest wastewater tests show.

An Australian Criminal Intelligence Commission report released on Tuesday shows use of the pain killer fentanyl more than doubled in regional Australia in the year to April 2018.

Use of the drug across the country was at its highest levels since the testing began, according to the fifth National Wastewater Drug Monitoring Program report.

Pop music legend Prince died of an accidental fentanyl overdose in 2016, and ACIC is concerned by the increased consumption rates within Australia, as the high potency of the drug increases the risk of overdose.

Out of the 23 countries with comparable data, Australia is second behind the US for MDMA, cocaine, amphetamine and methylamphetamine use.

The wastewater tests from April 2018 checked for 12 drugs and covered more than half of the Australian population, with 47 wastewater treatment plants participating across the country.

Nicotine and alcohol remain the most consumed substances of those tested, while methylamphetamine levels were the highest in the illicit drug category.

Although consumption varies across states and territories, the data shows an overall decrease in average use for many of the drugs tested, including cocaine, MDMA, MDA, heroin and oxycodone.

Methylamphetamine use decreased in regional Australia while increasing in the cities.

Use of the drug markedly decreased in South Australia and Western Australia between December 2017 and April 2018.

ACIC chief executive Michael Phelan says the data will help direct resources to priority areas of organised crime.

Previous data showed Australians used an estimated 8.3 tonnes of methylamphetamine, more than 3 tonnes of cocaine, 1.2 tonnes of MDMA and more than 700 kilograms of heroin in the year from August 2016 to August 2017.

DRUGS USE ACROSS AUSTRALIA

- ACT: highest use of fentanyl in a capital city, increased use of methylamphetamine, cocaine, MDA, oxycodone, fentanyl and heroin

- NSW: highest levels of cocaine use in a capital city and regionally, highest regional use of MDMA, MDA and fentanyl, increased methylamphetamine consumption across the state

- NT: highest levels of nicotine and alcohol, most methylamphetamine and MDMA use in a capital city

- QLD: Fentanyl use on the rise, second highest regional consumption of cocaine

- TAS: highest consumption of MDA, oxycodone and fentanyl in a capital city

- VIC: highest levels of heroin use, increasing fentanyl use and highest regional consumption of oxycodone

- WA: highest methylamphetamine use in regional areas