Big increase in Qld ice residue: study

SYDNEY, March 4 AAP - The levels of methamphetamine found in the wastewater of a Queensland city increased fivefold since 2009, according to new research.

The "huge" increase confirms evidence and speculation that the use of ice in Australia is on the rise, Professor Wayne Hall told AAP.

"It's all confirming that we are not imagining we have had a big increase in the use of this drug - which is what some people have been saying, that it is a bit of a beat-up."

Prof Hall, from the University of Queensland's Centre for Youth Substance Abuse Research, and colleagues analysed wastewater samples from two treatment plants in southeast Queensland.

They obtained 498 samples from a plant serving a coastal metropolitan city that included entertainment precincts between 2009-2015 and 712 from one serving a major inland regional city.

Meth consumption, measured in milligrams per day per 1000 inhabitants, was higher in the metropolitan city than in the regional one, and levels in both increased significantly.

"Consumption increased 4.8 times in the metropolitan area between 2009 and 2015, and 3.4 times in the regional city between 2010 and 2015," the authors said in their report published in the Medical Journal of Australia.

They noted the data didn't allow them to decide whether the increase was due to more new users and/or because current users are consuming higher doses of a purer drug.

But the results were consistent with trends found in a South Australian wastewater study and with the increase in arrests for ice use and supply and the number of users seeking treatment.

"When we have looked at other drugs (in wastewater) they did not show such a striking pattern of increase," Prof Hall said.

A condition of getting access to the wastewater was to not identify the Qld cities.

Another recently published paper estimated that there were 268,000 regular ice users in Australia with 160,000 dependent on the drug.

The estimates suggested the numbers have substantially risen during the past five years.