Elevated Exposures to Polycyclic Aromatic Hydrocarbons and Other Organic Mutagens in Ottawa Firefighters Participating in Emergency, On-Shift Fire Suppression

Abstract

Occupational exposures to combustion emissions were examined in Ottawa Fire Service (OFS) firefighters. Paired urine and dermal wipe samples (i.e., pre- and post-event) as well as personal air samples and fire event questionnaires were collected from 27 male OFS firefighters. A total of 18 OFS office workers were used as additional controls. Exposures to polycyclic aromatic hydrocarbons (PAHs) and other organic mutagens were assessed by quantification of urinary PAH metabolite levels, levels of PAHs in dermal wipes and personal air samples, and urinary mutagenicity using the Salmonella mutagenicity assay (Ames test). Urinary Clara Cell 16 (CC16) and 15-isoprostane F (8-iso-PGF) levels were used to assess lung injury and overall oxidative stress, respectively. The results showed significant 2.9- to 5.3-fold increases in average post-event levels of urinary PAH metabolites, depending on the PAH metabolite (p < 0.0001). Average post-event levels of urinary mutagenicity showed a significant, event-related 4.3-fold increase (p < 0.0001). Urinary CC16 and 8-iso-PGF did not increase. PAH concentrations in personal air and on skin accounted for 54% of the variation in fold changes of urinary PAH metabolites (p < 0.002). The results indicate that emergency, on-shift fire suppression is associated with significantly elevated exposures to combustion emissions.

Firefighters’ absorption of PAHs and VOCs during controlled residential fires by job assignment and fire attack tactic

“…Although some of these firefighters could have had inhalation exposure prior to structure entry when SCBA was worn (due to environmental smoke, n = 20) or when removing their SCBA postresponse (due to off-gassing turnout gear, n = 2) [43,44], we found no difference in exhaled breath concentrations of benzene by these factors. Thus, the findings here support previous work suggesting that dermal absorption plays an important role in the accumulation of toxicants during firefighting [16,18,19].…”

“…The PAH metabolites were measured using an enzyme-linked immunosorbent assay (ELISA), which is not specific, but correlates well (r = 0.89) with the sum of metabolites of four PAHs (naphthalene, fluorene, phenanthrene, and pyrene) measured by gas chromatography-mass spectrometry in exposed workers' urine [34]. Other studies of firefighters have documented post-fire increases in metabolites of phenanthrene, fluorene, and pyrene [15,16].…”

“…Although the inhalation route is protected by use of SCBA, the potential for dermal exposure still exists. Studies have found PAH particulates under firefighters' protective ensembles (i.e., turnout gear) and contaminating the skin following fire responses [15][16][17][18][19][20] and PAHs can be readily absorbed through skin [21][22][23][24].…”

“…Several studies have documented increased excretion of PAH and/or benzene metabolites in urine or breath following structural firefighting [15,16,18,[30][31][32]. In many of these studies, both dermal and inhalation routes could have contributed to the systemic levels.…”

Polycyclic aromatic hydrocarbons in the firefighter workplace: The results from the first in Poland short-term measuring campaign

“…Smoke emitted by a fire contains carcinogens [11][12][13][14][15]. From among the polycyclic aromatic hydrocarbons (PAHs) released into the air in vast amounts during a fire, are benzo[a]pyrene, which is carcinogenic to humans, dibenz [a,h] [16,17].…”