Firefighters' skin may be exposed to chemicals via permeation/penetration of combustion byproducts through or around personal protective equipment (PPE) or from the cross-transfer of contaminants on PPE to the skin. Additionally, volatile contaminants can evaporate from PPE following a response and be inhaled by firefighters. Using polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) as respective markers for non-volatile and volatile substances, we investigated the contamination of firefighters' turnout gear and skin following controlled residential fire responses. Participants were grouped into three crews of twelve firefighters. Each crew was deployed to a fire scenario (one per day, four total) and then paired up to complete six fireground job assignments. Wipe sampling of the exterior of the turnout gear was conducted pre- and post-fire. Wipe samples were also collected from a subset of the gear after field decontamination. VOCs off-gassing from gear were also measured pre-fire, post-fire, and post-decon. Wipe sampling of the firefighters' hands and neck was conducted pre- and post-fire. Additional wipes were collected after cleaning neck skin. PAH levels on turnout gear increased after each response and were greatest for gear worn by firefighters assigned to fire attack and to search and rescue activities. Field decontamination using dish soap, water, and scrubbing was able to reduce PAH contamination on turnout jackets by a median of 85%. Off-gassing VOC levels increased post-fire and then decreased 17-36 min later regardless of whether field decontamination was performed. Median post-fire PAH levels on the neck were near or below the limit of detection (< 24 micrograms per square meter [µg/m]) for all positions. For firefighters assigned to attack, search, and outside ventilation, the 75 percentile values on the neck were 152, 71.7, and 39.3 µg/m, respectively. Firefighters assigned to attack and search had higher post-fire median hand contamination (135 and 226 µg/m, respectively) than other positions (< 10.5 µg/m). Cleansing wipes were able to reduce PAH contamination on neck skin by a median of 54%.

Turnout gear provides protection against dermal exposure to contaminants during firefighting; however, the level of protection is unknown. We explored the dermal contribution to the systemic dose of polycyclic aromatic hydrocarbons (PAHs) and other aromatic hydrocarbons in firefighters during suppression and overhaul of controlled structure burns. The study was organized into two rounds, three controlled burns per round, and five firefighters per burn. The firefighters wore new or laundered turnout gear tested before each burn to ensure lack of PAH contamination. To ensure that any increase in systemic PAH levels after the burn was the result of dermal rather than inhalation exposure, the firefighters did not remove their self-contained breathing apparatus until overhaul was completed and they were >30 m upwind from the burn structure. Specimens were collected before and at intervals after the burn for biomarker analysis. Urine was analyzed for phenanthrene equivalents using enzyme-linked immunosorbent assay and a benzene metabolite (s-phenylmercapturic acid) using liquid chromatography/tandem mass spectrometry; both were adjusted by creatinine. Exhaled breath collected on thermal desorption tubes was analyzed for PAHs and other aromatic hydrocarbons using gas chromatography/mass spectrometry. We collected personal air samples during the burn and skin wipe samples (corn oil medium) on several body sites before and after the burn. The air and wipe samples were analyzed for PAHs using a liquid chromatography with photodiode array detection. We explored possible changes in external exposures or biomarkers over time and the relationships between these variables using non-parametric sign tests and Spearman tests, respectively. We found significantly elevated (P < 0.05) post-exposure breath concentrations of benzene compared with pre-exposure concentrations for both rounds. We also found significantly elevated post-exposure levels of PAHs on the neck compared with pre-exposure levels for round 1. We found statistically significant positive correlations between external exposures (i.e. personal air concentrations of PAHs) and biomarkers (i.e. change in urinary PAH metabolite levels in round 1 and change in breath concentrations of benzene in round 2). The results suggest that firefighters wearing full protective ensembles absorbed combustion products into their bodies. The PAHs most likely entered firefighters’ bodies through their skin, with the neck being the primary site of exposure and absorption due to the lower level of dermal protection afforded by hoods. Aromatic hydrocarbons could have been absorbed dermally during firefighting or inhaled during the doffing of gear that was off-gassing contaminants.

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. The ELISA had a minimum detectable concentration (MDC) of 0.06 g/ml, which, when dilution adjusted, yielded a whole-serum MDC of 3.0 g of anti-PA IgG per ml. The reliable detection limit (RDL) was 0.09 g/ml, while the dynamic range was 0.06 to 1.7 g/ml. The diagnostic sensitivity of the assay was 97.6% and the diagnostic specificity was 94.2% for clinically verified cases of anthrax. A competitive inhibition anti-PA IgG ELISA was also developed to enhance the diagnostic specificity to 100%. We report a newly developed fluorescence covalent microbead immunosorbent assay (FCMIA) for B. anthracis PA which was Luminex xMap technology. The FCMIA MDC was 0.006 g of anti-PA IgG per ml, the RDL was 0.016 g/ml, and the whole-serum equivalent MDC was 1.5 g/ml. The dynamic range was 0.006 to 6.8 g/ml. Using this system, we analyzed 20 serum samples for anti-PA IgG and compared our results to those measured by ELISA in a double-masked analysis. The two methods had a high positive correlation (r 2 ‫؍‬ 0.852; P < 0.001). The FCMIA appears to have benefits over the ELISA for the measurement of anti-PA IgG, including greater sensitivity and speed, enhanced dynamic range and reagent stability, the use of smaller sample volumes, and the ability to be multiplexed (measurement of more than one analyte simultaneously), as evidenced by the multiplexed measurement in the present report of anti-PA and anti-lethal factor IgG in serum from a confirmed clinical anthrax infection.In response to the anthrax terrorist attacks of 2001, the Centers for Disease Control and Prevention (CDC) undertook accelerated development for a quantitative enzyme-linked immunosorbent assay (ELISA) for detection of anti-protective antigen (PA)-specific immunoglobulin G (IgG) in human serum and the development of a competitive inhibition assay to enhance diagnostic specificity (15). This assay was shown to have a diagnostic sensitivity of 97.6% and a diagnostic specificity of 94.2%. Preadsorption of sera with PA enhanced the diagnostic specificity to 100%. A potential limitation of ELISA is that it is a monoplex technology. Only one analyte can be measured per assay; measurement of numerous analytes necessitates either simultaneous or sequential assays. When the number of analytes becomes large, resource and manpower limitations can occur. An alternative to the ELISA is an assay that can multiplex analytes, i.e., measure numerous analytes simultaneously. Fluorescent covalent microsphere immunoassay (FCMIA) is a technology that can accomplish this by using uniquely dually stained microspheres for the measurement of up to 100 analytes simultaneously (18). In the present report we describe a newly developed FCMIA and compare it to a specific, sensitive, and quantitative ELISA for anti-PA IgG and also present multiplexed data for measuring anti-PA and antilethal factor (LF) IgG in serum from a confirmed case of human clinical anthrax. MATERIALS AND METHODSSerum samples. Twenty-two serum samples (3 quality control standards, 1 negative control standard, and 16 unk...