Second-hand smoke exposure in Scotland has decreased by 96% since the country's smoke-free legislation took effect on March 26, 2006, according to new research by the University of Stirling and Public Health Scotland. The findings were released on Mar. 26 as part of a study marking two decades since the law was enacted.
The reduction in second-hand smoke is seen as a major public health achievement, but researchers note that some workers remain exposed to tobacco smoke in places not fully covered by current laws, such as private homes visited by care workers and outdoor hospitality venues.
The study, led by Professor Sean Semple from the University of Stirling's Institute for Social Marketing and Health, analyzed data from the Scottish Health Survey spanning from 1998 to 2024. It found a nearly 96% drop in average salivary cotinine levels—a biomarker for tobacco exposure—among non-smokers during this period. However, improvements have slowed since 2011; in 2024 almost one quarter of non-smoking adults still had measurable levels of cotinine.
"Scotland's smoke-free legislation has delivered extraordinary public health gains. The scale of the reduction in second-hand smoke exposure since 2006 is remarkable and shows how effective bold legislation can be," said Semple. He added: "But nearly a quarter of non-smokers are still exposed to tobacco smoke... No one should be forced to breathe in tobacco smoke while doing their job." Semple also emphasized that repeated low-level exposure continues to pose health risks and called for renewed focus on protecting workers and addressing inequalities related to home exposure.
Between 2012 and 2024, the proportion of Scottish households with indoor smoking bans rose from about three-quarters to over ninety percent—an increase representing approximately 380,000 additional smoke-free homes. Despite this progress, inequality has grown: households in deprived communities are now more than ten times more likely to allow indoor smoking compared with those in less deprived areas.
Dr Garth Reid, Consultant in Public Health at Public Health Scotland said: "Smoking is one of the biggest causes of ill health and premature death in Scotland... Thanks to the smoking ban we have historically low smoking rates." Reid encouraged people who want help quitting smoking to use NHS services or local pharmacies.
Public Health Minister Jenni Minto called banning indoor public place smoking "a landmark moment for Scotland" and highlighted that cigarette smoking has almost halved since then. She noted new legislative efforts under consideration that would give ministers powers to expand existing smoke-free spaces as well as create vape- and heated tobacco-free zones.
