Methamphetamine residue found in the wastewater of a Queensland city has multiplied five times since 2009, while the total number of users in Australia is greater than the population of Hobart.
“There has been ongoing debate about whether the number of methamphetamine users in Australia has increased significantly or whether it is a small percentage of the population using a lot more,” Professor Hall said.
“These studies when viewed together are consistent with there being exponential growth in the number of users.”
Professor Hall collaborated with UQ colleagues from The National Research Centre for Environmental Toxicology (Entox) to test wastewater in south-east Queensland.
More than 1000 samples were taken from a coastal metropolitan city and a major inland regional city between 2009 and 2015.
Consumption increased 4.8 times in the metropolitan area over the timeframe, and 3.4 times in the regional area.
“Over a similar period across Australia from 2009 to 2014, a concurrent study showed an upsurge of more than 170,000 regular users to a total of 270,000 users,” Professor Hall said
“A regular user was defined as someone using at least once per month.
“The number of dependent methamphetamine users – those with impaired control over their usage – was estimated at 160,000.
“Highest usage rates were found among those aged 25-34, while the sharpest increase was in the 15-24 bracket.”
The study on national estimates was led by Professor Louisa Degenhardt from the National Drug and Alcohol Research Centre at the University of New South Wales.
A total of 270,000 users is greater than 2014 population figures for Hobart (219,243) and Townsville (178,649), and marginally less than the Wollongong region (289,236).
Both the wastewater study and the study on Australian usage estimates have been published by The Medical Journal of Australia.
Words: Rob Burgin