Exposure to pro- and anti-tobacco messages online and off-line among people experiencing homelessness.

The prevalence of cigarette smoking among people experiencing homelessness is 70%. The internet is a common mode of exposure to tobacco-related messaging, yet little is known about these exposures among people experiencing homelessness. Using time-location sampling, we recruited a sample of adults experiencing homelessness who were current cigarette smokers (i.e. smoked in the past 30 days) from shelters and service sites in San Francisco. We administered a survey to explore self-reported use of the internet and online streaming services; and exposure to tobacco messaging online and offline. Of the 470 participants, 75.5% reported using the internet and 67.2% reported using online streaming video in a typical week. Many participants had seen online advertisements for tobacco products ( = 197, 41.7%) or anti-tobacco industry messages ( = 215, 45.6%), although participants reported seeing both advertisements and warnings related to tobacco more frequently offline than online. Respondents who reported using the internet for more than 4 h in a typical week were more likely to recall seeing tobacco-related warnings or advertisements online. Respondents who reported seeing tobacco-related warnings and advertisements were more likely to have attempted to quit smoking within the past year. These findings suggest an opportunity to use the internet to communicate the harms of tobacco products with messages tailored towards adults experiencing homelessness. Our results suggest further that now is the time to saturate the internet and online streaming services with anti-tobacco industry messages before advertisements for tobacco products become as ubiquitous online as they are elsewhere.