Characterization of Volatile Organic Compounds in Smoke at Municipal Structural Fires

Abstract

The objective of this study was to characterize volatile organic compounds (VOCs) found at municipal structural fires in order to identify sources of long-term health risks to firefighters, which may be contributing factors in heart disease and cancer. Firefighters collected air into evacuated Summa canisters inside burning buildings at nine municipal structural fires under conditions where they judged that at least some firefighters might remove their self-contained breathing apparatus masks. Volatile organic compounds were identified and quantified for 144 target compounds using cryogenic preconcentration and gas chromatography/mass spectral detection (GC/MSD) methodology operating in selected ion monitoring mode. Samples were also analyzed in SCAN mode and examined for the appearance of substances that were not present in the instrument standard calibration mixture. The spectra of municipal structural fires were surprisingly similar and remarkable for their simplicity, which was largely due to the dominating presence of benzene along with toluene and naphthalene. Propene and 1,3-butadiene were found in all of the fires, and styrene and other alkyl-substituted benzene compounds were frequently identified. Similar "fingerprints" of the same 14 substances (propene, benzene, xylenes, 1-butene/2-methylpropene, toluene, propane, 1,2-butadiene, 2-methylbutane, ethylbenzene, naphthalene, styrene, cyclopentene, 1-methylcyclopentene, isopropylbenzene) previously identified at experimental fires burning various solid combustible materials were also found at municipal structural fires, accounting for 76.8% of the total VOCs measured. Statistically significant positive correlations were found between increasing levels of benzene and levels of propene, the xylenes, toluene, 1-butene/2-methylpropene, 1,3-butadiene, and naphthalene. Given the toxicity/carcinogenicity of those VOCs that were found in the highest concentrations, particularly benzene, 1,3-butadiene, and styrene, further investigation of VOC exposures of firefighters is warranted. Benzene, or its metabolic product s-phenylmercapturic acid in urine, was identified as a suitable chemical marker for firefighter exposure to combustion products.

Chemical exposure and hearing loss

“…Environmental exposure studies have determined the concentration of combustion products and various toxic agents in the smoke to which firefighters may be exposed. [40][41][42][43][44] According to these studies, smoke contains numerous harmful chemicals such as acrolein, benzene, methylene chloride, polyaromatic hydrocarbons, perchloroethylene, carbon monoxide, toluene, trichloroethylene, trichlorophenol, xylene, and formaldehyde. In addition, combustion products include metals such as lead, cadmium, mercury, and arsenic.…”

Health hazard evaluation report: evaluation of dermal exposure to polycyclic aromatic hydrocarbons in fire fighters.

“…These levels far exceed the levels of benzene (80-360 µg/ m 3 ) and toluene (40-300 µg/m 3 ) measured by Queensland Fire and Rescue Service investigators during similar types of structural training fires [QFRS 2011a,b]. However, similar air concentrations of benzene (70,000 µg/m 3 [Jankovic et al 1991]) and higher air concentrations of toluene (20,000 µg/m 3 [Austin et al 2001b]) have been reported during knockdown of structure fires. Because toluene has a similar rate of dermal absorption as benzene [Franz 1984], we would expect the post-exposure increase in benzene concentrations to be around 16 times greater than the post-exposure increase in toluene concentrations for the exhaled breath samples collected during the last day of round 2.…”

Health hazard evaluation report: HETA-2008-0241-3113, evaluation of chemical and particle exposures during vehicle fire suppression training, Miami Township Fire and Rescue, Yellow Springs, Ohio.

“…According to an analysis by Austin et al [2001], fire fighters in Montreal were estimated to wear SCBAs approximately 50% of the time at structural fires, but only 6% of the time at all fires (which included vehicle fires). Possible reasons for not wearing an SCBA during vehicle fires include the following: vehicle fires tend to be suppressed quickly (within a few minutes) and thus, exposures are assumed to be minimal, donning an SCBA takes time and is cumbersome to wear, and the belief that breathing air should be saved for more intense fires when it is really needed.…”

“…Investigators in this study reported potentially harmful levels of hydrogen chloride, sulfur dioxide, aromatic hydrocarbons (benzene), PAHs, aldehydes (formaldehyde), dioxins and furans, and isocyanates. Many more studies investigating fire fighter exposures during structural fires have been conducted [Gold et al 1978;Treitman et al 1980;Brandt-Rauf et al 1988;Jankovic et al 1991;Bolstad-Johnson et al 2000;Austin et al 2001]. High levels (in excess of STELs) of CO, formaldehyde, acrolein, hydrogen chloride, hydrogren cyanide, sulphuric acid, and hydrogen fluoride have been reported during knockdown of structural fires [Jankovic et al 1991].…”