Key findings
Data from the National Health and Nutrition Examination Survey
During 2015–2018, 20.8% of nonsmoking U.S. adults aged 18 and over were exposed to secondhand tobacco smoke (SHS) as measured by cotinine in the blood.
The prevalence of SHS exposure was greater for adults aged 18–39 (25.6%) than for those aged 40–59 (19.1%) and 60 and over (17.6%).
Exposure to SHS was more prevalent among non-Hispanic black adults (39.7%) compared with non-Hispanic white (18.4%), non-Hispanic Asian (20.9%), and Hispanic (17.2%) adults.
Adults with some college education had a lower prevalence of SHS exposure compared with those with a high school education or less, and the percentage of SHS-exposed adults decreased with increasing family income.