Degree Name

Doctor of Philosophy


School of Management, Operations and Marketing


Moving consumers into more sustainable consumption patterns is arguably one of the most difficult behaviour change targets, particularly when competing against strongly habitualised behaviours. A change in context, however, in which bad habits were otherwise sustained, facilitates favourable conditions for behaviour modification. The removal of single-use plastic bags in Australia provided such favourable conditions. Given that little is known about the consequences of plastic bag charges, this study uses the Theory of Planned behaviour to explore the implications of the single-use plastic bag phase out in Australia in terms of people’s changes in attitudes, social norms and perceived behavioural control (PBC). This research also investigates whether the phase out can lead to an uptake of other, related pro-environmental behaviours (i.e., spillover behaviours). A quantitative research approach was used, employing a longitudinal trend study based on the Theory of Planned Behaviour (TPB) variables and measures of spillover over time. A panel survey was used to collect data over a 9-month period between June 2018 and February 2019. Data was collected in three stages: two to three weeks before (n = 200), during (n = 342) and six months after (n = 346) the phase out.

Quantitative data analysis involved multivariate analyses of variance (MANOVA) as well as structural equation modelling (SEM). The SEM output revealed good fit of the theoretical model, with most hypothesised relationships staying stable over time. The findings indicate that overall, the single-use plastic bag phase out in Australia resulted in higher behavioural intention to use reusable shopping bags. Informational social influence was the strongest predictor of intention to use reusable bags after the phase out. The influence of attitudes, however, was found to be negative during transition as well as six months after the implementation, likely due to the extrinsic nature of the intervention. While no evidence for spillover was found, the positive influence of informational social norms and hedonic attitudes could lay the groundwork for the future uptake in other, related pro-environmental behaviour.



Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.