To better understand the absorption of combustion byproducts during firefighting, we performed biological monitoring (breath and urine) on firefighters who responded to controlled residential fires and examined the results by job assignment and fire attack tactic. Urine was analyzed for metabolites of polycyclic aromatic hydrocarbons (PAHs) and breath was analyzed for volatile organic compounds (VOCs) including benzene. Median concentrations of PAH metabolites in urine increased from pre-firefighting to 3-h post firefighting for all job assignments. This change was greatest for firefighters assigned to attack and search with 2.3, 5.6, 3.9, and 1.4-fold median increases in pyrene, phenanthrene, naphthalene, and fluorene metabolites. Median exhaled breath concentrations of benzene increased 2-fold for attack and search firefighters (p < 0.01) and 1.4-fold for outside vent firefighters (p = 0.02). Compared to interior attack, transitional attack resulted in 50% less uptake of pyrene (p = 0.09), 36% less uptake phenanthrene (p = 0.052), and 20% less uptake of fluorene (p < 0.01). Dermal absorption likely contributed to firefighters' exposures in this study. Firefighters' exposures will vary by job assignment and can be reduced by employing a transitional fire attack when feasible.
Keywords: Benzene; Biomarker; Breath; Firefighter; PAH; Urine.