Trends in methamphetamine residues in wastewater in metropolitan and regional cities in south-east Queensland, 2009–2015
Over the past several years, the Australian media have reported increased use and harm arising from the use of crystal methamphetamine (“ice”),1,2 a highly pure form of the drug that can be smoked or injected.2 We used wastewater analysis to examine trends in methamphetamine residues in wastewater samples from the inlets of two treatment plants in south-east Queensland. One plant served a coastal metropolitan city that included entertainment precincts and the other a major inland regional city.
Wastewater analysis is an approach to monitoring illicit drug use in the population,3 in which liquid chromatography and mass spectrometry are used to measure the concentrations of illicit drug residues in wastewater. We used drug-specific excretion factors and the de jure population from the Australian Bureau of Statistics 2011 census data for these catchments to estimate the amount of methamphetamine consumed by people who contributed to the wastewater samples.
We collected a total of 498 samples in the metropolitan city (2009–2015) and 712 samples in the regional city (2010–2015). Details of the sampling, analytical and back-calculation methods are described in the