RT Journal Article SR Electronic T1 Impact of the FDA flavour enforcement policy on flavoured electronic cigarette use behaviour changes JF Tobacco Control JO Tob Control FD BMJ Publishing Group Ltd SP s176 OP s183 DO 10.1136/tc-2022-057492 VO 31 IS Suppl 3 A1 Li, Dongmei A1 Ossip, Deborah J A1 Bansal-Travers, Maansi A1 Xie, Zidian YR 2022 UL http://tobaccocontrol.bmj.com/content/31/Suppl_3/s176.abstract AB Introduction This study aims to investigate electronic cigarette (e-cigarette) use behaviour changes after the implementation of the US Food and Drug Administration (FDA) restriction on the sale of all unauthorised flavoured cartridge-based e-cigarettes other than tobacco and menthol flavour on 6 February 2020, as well as factors associated with these changes.Methods Through Amazon’s Mechanical Turk service, 3533 current adult flavoured e-cigarette users (who were not exclusive tobacco-flavoured or menthol-flavoured e-cigarette users) were recruited for an online survey from 8 July to 29 July 2021. Multiple logistic regression models were used to identify significant factors associated with quitting e-cigarette use, switching to other flavoured electronic nicotine delivery system (ENDS) products, switching to combustible tobacco products, switching to menthol-flavoured e-cigarettes and switching to tobacco-flavoured e-cigarettes.Results Resulting from the FDA flavour enforcement policy, the top four e-cigarette use behaviour changes were: (1) switching to other flavoured ENDS products such as the tank system or disposable e-cigarettes (29.24%), (2) switching to menthol-flavoured pod systems (18.09%), (3) switching to combustible tobacco products (14.12%) and (4) switching to tobacco-flavoured pod systems (12.03%). There were 4.9% participants who indicated that they quit e-cigarette use. Overall, multiple factors, especially past 30-day use of certain flavours, were associated with different behaviour changes.Conclusions The implementation of the FDA flavour enforcement policy on cartridge-based e-cigarette was associated with significant e-cigarette behaviour changes, with multiple factors being associated with these changes. These results provide important information for future regulations of flavoured e-cigarette products.Data are available on reasonable request. Data are available on reasonable request through corresponding author.