Impact of wildfire smoke, heat stress and sleep deprivation on the brain health of wildland firefighters

Wildland firefighters (WLFFs) face significant brain health risks due to prolonged exposure to smoke, extreme heat, dehydration, physical exertion and irregular sleep patterns. Here, the literature is presented as a narrative review on studies that inform our knowledge on WLFF brain health. The neurotoxic components of wildfire smoke, such as particulate matter, carbon monoxide and polycyclic aromatic hydrocarbons, can disrupt brain function by inducing oxidative stress, neuroinflammation and hypoxia, which can contribute to cognitive decline and increase the risk of neurodegenerative diseases. Chronic heat exposure can exacerbate these risks leading to impaired cognitive functions including attention, memory, and decision-making. Sleep deprivation and extended shifts can compound cognitive and mood impairments through elevated stress hormone levels and inflammatory cytokines. Psychological stressors in wildland firefighting, including exposure to traumatic events, increase vulnerability to post-traumatic stress, anxiety, depression and suicidal ideation. Protective strategies for WLFFs should include personal protective equipment, hydration protocols, extended recovery periods and mental health programs. Future research should focus on long-term studies to fully understand the cumulative effects of these occupational hazards on brain health and inform policy changes to safeguard WLFF well-being. This holistic approach is critical as fire seasons become longer and more intense due to climate change.