Second-hand smoke linked to 1.7 million deaths globally, study finds

Millions of non-smokers are dying due to second-hand smoke.

More than 2.7 billion people including children have been exposed to second-hand smoke globally, contributing to nearly 1.7 million deaths in 2023, according to study published Tuesday in The Lancet.

Tobacco remains a leading cause of disease globally, the study said, noting many "non-smokers exposed to second-hand smoke" were among the estimate total of 8 million people who died in 2023 of smoking-related illnesses.

"Exposure to second-hand smoke is a globally recognised health risk, with no safe level of inhalation," it said.

By reviewing studies published in the US National Institutes of Health database PubMed along with population surveys, Tuesday's study sought to estimate the prevalence of exposure to second-hand smoke and quantify the burden of disease in 204 countries and territories between 1990 and 2023.