Increases in Secondhand Smoke After Going Smoke-Free: An Assessment of the Impact of a Mandated Smoke-Free Housing Policy

Objective: The 12-month impact of federally mandated smoke-free housing (SFH) policy adoption (July 2018) was assessed using two markers of ambient secondhand smoke (SHS): airborne nicotine and particulate matter at the 2.5-micrometer threshold (PM2.5). Methods: We measured markers of SHS in Norfolk, VA from December 2017 to December 2018 in six federally subsidized multi-unit public housing buildings. Multi-level regression was used to model the following comparisons: (1) the month immediately before SFH implementation versus the month immediately after, and (2) December 2017 versus December 2018. Results: There was a 27% reduction in indoor PM2.5 and a 32% reduction in airborne nicotine in the first month after SFH adoption, compared to the month prior to adoption. However, there was a 33% increase in PM2.5 and a 25% increase in airborne nicotine after 12 months. Conclusions: US Department of Housing and Urban Development (HUD)-mandated SFH can reduce SHS in multi-unit housing. However, SFH could also plausibly increase indoor smoking. Policy approaches adopted by individual properties or housing authorities-for example, property-wide bans versus allowing designated smoking areas-could be driving this potential unintended consequence.