Twenty years on from smoke-free legislation in Scotland: A secondary analysis of the Scottish Health Survey dataset ( 1998–2024 ) examining changes in household smoking rules, and salivary cotinine concentrations among non-smokers

Scotland has sustained large reductions in SHS exposure since smoke-free legislation was introduced twenty years ago in 2006. However, progress evident in the years between 2006 and 2011 has not been maintained: there are still nearly one-quarter of non-smoking adults having measurable exposure to SHS on any given day. Smoking in the home has also reduced, but the level of inequality of this measure has doubled between 2012 and 2024. Public health interventions should consider the remaining workplace and home settings where people experience exposure to SHS.