Wildland firefighters are exposed to health hazards including inhaling hazardous pollutants from the combustion of live and dead vegetation (smoke) and breathe soil dust, while working long shifts with no respiratory protection. This research brief summarizes a study analyzing long-term health impacts of smoke exposure for wildland firefighters (Navarro et al. 2019). The study estimated relative risk of lung cancer and cardiovascular disease mortality from existing particulate matter (PM) exposure-response relationships using a measured PM concentration from smoke and breathing rates from previous wildland firefighter studies across different exposure scenarios.