A wastewater‐based assessment of the impact of a minimum unit price (MUP) on population alcohol consumption in the Northern Territory, Australia

Abstract

Aim To test if there was a reduction in alcohol consumption in wastewater samples in the Northern Territory of Australia after the implementation of a minimum unit alcohol price policy (MUP) in October 2018. Design, setting, cases Between August 2016 and February 2020, wastewater samples were collected across 66 sites in the Northern Territory and all other states and territories in Australia. Samples were collected every 2 months in capital cities and every 4 months in regional places during this period. Overall, 4917 samples were taken (2816 before MUP and 2101 after). Measurements The number of standard drinks per 1000 people per day in the respective catchment areas was estimated based on the concentration of an alcohol‐specific metabolite, ethyl sulphate in the samples (using the excretion factor of ethyl sulphate, the flow of wastewater entering the wastewater treatment plants and the population of each wastewater catchment). Findings Results from a linear mixed model showed that there was a large drop in alcohol consumption immediately after the MUP in Northern Territory [estimated drop = 1231, 99% confidence interval (CI) = 830, 1633; 38.75%]. There was no significant drop in all other states/territories except for Queensland, which showed a significant but much smaller drop (estimated drop: 310; 99% CI = 114, 550). One year after the MUP, the drop narrowed to 520 (99% CI = 189, 851) and was no longer statistically significant in February 2020 (15 months after MUP; estimated drop = 283, 99% CI = −114, 681). Conclusions Per‐capita consumption of alcohol appears to have decreased substantially in the Northern Territory of Australia immediately after the implementation of a minimum unit price but consumption steadily recovered and almost returned to the pre‐MUP consumption level after 15 months.

A Framework for Public Health Authorities to Evaluate Health Determinants for Wastewater-Based Epidemiology

“…However, estimates of per capita consumption can be used to investigate general patterns of consumption, including spatiotemporal variation (e.g., weekly and long-term trends, 93 , 95 geographic variation or hotspots 95 , 96 ) and behaviors (e.g., during festivals or holidays 93 , 97 ) and to assess the effectiveness of interventions. 26 …”

“… 69 , 93 , 95 This consistent relationship allows for both temporal and spatial comparisons of consumption, 95 as well as assessment of public health interventions. 26 …”

“…During this evaluation, it is important to consider the overall objectives and constraints of the program because context, priorities, and resource availability are likely to differ between the applied use of WBE by public health authorities and academic, curiosity-driven research. For example, will the data generated by WBE be used to inform immediate public health responses, 25 evaluate the effect of interventions, 26 guide policy making, 27 or support long-term monitoring of trends, 28 or will it help to expand academic knowledge? WBE is most useful in supporting public health outcomes if the data produced relates to a relevant public health issue, can be clearly and correctly interpreted, and is actionable in some way.…”

Causal inference with observational data in addiction research

“…For example, O'Brien et al . [29] tested the effect of minimum alcohol pricing on population‐level alcohol consumption in the Northern Territory, Australia.…”

A wastewater‐based evaluation of the effectiveness of codeine control measures in Australia

“…WBE provides a complementary approach to evaluate the effects of policy changes on the population consumption of licit and illicit drugs, including opioids [ 9 ]. It has recently evaluated the impact of minimum unit pricing on alcohol products in Northern Territory, Australia [ 10 ]. Wastewater‐based studies collect representative samples of community urine from municipal sewage treatment plants and analyse levels of human metabolites of the target substances in the samples.…”