Inflammatory and psychological consequences of chronic high exposure firefighting.

Objectives: This study aimed to examine the impact of extreme heat exposure frequency on inflammation and well-being in UK Fire Service personnel.

Methods: 136 Fire personnel and 14 controls (CON) were recruited [92 Firefighters (FF), 44 Breathing Apparatus Instructors (BAI)]. BAI were split into low (LBAI; ≤15 exposures per month) and high (HBAI; ≥20 exposures per month) categories. Measures of inflammation, mood and fatigue were collected at 0, 3 and 6 month times points. These variables were analysed for differences between groups and association with frequency of exposure.

Results: HBAI exhibited raised IL-1β, IL-6, IL-10, IgE and lower IgM (p < 0.05). In addition, IL-1β, IL-6, IL-10 and IgM were associated with monthly exposure number, with exposures accounting for 15.4% of the variance in IL-6, 11.8% of IL-1β and 25.2% of IL-10. No differences in mood or fatigue were reported (p > 0.05).

Conclusion: High exposure firefighting consistently causes systemic inflammation without perceptual recognition of potential health risks.