Nearly half of Oklahoma adults reported secondhand cannabis smoke exposure, linked to respiratory symptoms

SHCS exposure was reported by 42% of adults. Those exposed were more likely to be male, younger, non-Hispanic Black or Hispanic, lower SES, and had more respiratory symptoms. Respiratory symptoms were highest among those with both SHCS exposure and personal cannabis use. Young adulthood, Black race, and current cigarette/cannabis use were the strongest predictors of exposure.

Repeated cross-sectional online survey of 5,410 adults in Oklahoma (a state with legalized medical cannabis and limited smoke-free protections). Measured 30-day SHCS exposure in homes, vehicles, and indoor settings alongside harm perceptions, respiratory symptoms, and substance use.

As cannabis legalization expands, secondhand smoke is an emerging public health concern, particularly for populations with less ability to control their exposure environments. Oklahoma had limited smoke-free protections at the time of the study.

Secondhand tobacco smoke protections took decades to develop. With cannabis legalization outpacing indoor air regulations in many states, this study highlights that secondhand cannabis smoke exposure is already common and disproportionately affects socially vulnerable populations.

Self-reported exposure and symptoms may be subject to recall bias. Oklahoma-specific findings in a medical-cannabis-only state may not generalize. Cannot separate SHCS effects from personal cannabis or cigarette smoking effects. Cross-sectional design.