Characterization of fire investigators' polyaromatic hydrocarbon exposures using silicone wristbands.

BACKGROUND: Exposures to polyaromatic hydrocarbons (PAHs) contribute to cancer in the fire service. Fire investigators are involved in evaluations of post-fire scenes. In the US, it is estimated that there are up to 9000 fire investigators, compared to approximately 1.1 million total firefighting personnel. This exploratory study contributes initial evidence of PAH exposures sustained by this understudied group using worn silicone passive samplers. OBJECTIVES: Evaluate PAH exposures sustained by fire investigators at post-fire scenes using worn silicone passive samplers. Assess explanatory factors and health risks of PAH exposure at post-fire scenes. METHODS: As part of a cross-sectional study design, silicone wristbands were distributed to 16 North Carolina fire investigators, including eight public, seven private, and one public and private. Wristbands were worn during 46 post-fire scene investigations. Fire investigators completed pre- and post-surveys providing sociodemographic, occupational, and post-fire scene characteristics. Solvent extracts from wristbands were analyzed via gas chromatography-mass spectrometry (GC-MS). Results were used to estimate vapor-phase PAH concentration in the air at post-fire scenes. RESULTS: Fire investigations lasted an average of 148 minutes, standard deviation ± 93 minutes. A significant positive correlation (r=0.455, p<.001) was found between investigation duration and PAH concentrations on wristbands. Significantly greater time-normalized PAH exposures (p=0.039) were observed for investigations of newer post-fire scenes compared to older post-fire scenes. Regulatory airborne PAH exposure limits were exceeded in six investigations, based on exposure to estimated vapor-phase PAH concentrations in the air at post-fire scenes. DISCUSSION: Higher levels of off-gassing and suspended particulates at younger post-fire scenes may explain greater PAH exposure. Weaker correlations are found between wristband PAH concentration and investigation duration at older post-fire scenes, suggesting reduction of off-gassing PAHs over time. Exceedances of regulatory PAH limits indicate a need for protection against vapor-phase contaminants, especially at more recent post-fire scenes.

Self-reported and objectively measured occupational exposures, health, and safety concerns among fishermen: A cross-sectional Fishing Industry Safety and Health (FISH) pilot study.

BACKGROUND: Fishing industry workers are exposed to hazardous working conditions, engage in strenuous labor, and work long hours in variable weather conditions. Despite these known employment challenges, little is known of their perceived occupational health and safety concerns. In this pilot study, we: (1) describe fishermen's perceptions on worker- and organizational-level characteristics that impact occupational health and safety; and (2) estimate environmental exposure to polycyclic aromatic hydrocarbons (PAHs) encountered during fishing activities. METHODS: We collected both qualitative and quantitative data from Mississippi and Florida fishermen. Using an ethnographic approach, the study team conducted 1-h key informant interviews, administered a one-page demographic survey, and collected objective measurements to PAHs using silicone-based passive sampling wristbands. RESULTS: Study participants (n = 17) had a mean age of 50.9 years (SD = 11.7), 88.2% were male, 94.1% white, 100.0% non-Hispanic/Latino, and 52.9% were married. Approximately, 87.5% reported fishing as their primary job, with a mean of 26.4 years in the industry (SD = 15.3). Four broad themes describing the culture of the fishing industry, common workplace exposures that impact fishermen's safety and health, and facilitators and barriers to safety while working in the fishing industry were documented. Deckhands had the lowest mean exposure to PAHs (8.3 ppb), followed by crew members (11.0 ppb), captains (82.64 ppb), and net makers (208.1 ppb). CONCLUSIONS: Gulf coast fishermen expressed specific occupational health and safety concerns and were exposed to carcinogenic PAHs during regular work. Opportunities exist and strategies are needed for health protection and health promotion interventions among Gulf fishermen.

Mapping carcinogen exposure across urban fire incident response arenas using passive silicone-based samplers.

Carcinogens are emitted in significant quantities at fire scenes and are a major contributor in the increased cancer risk observed in firefighters when compared to the general population. A knowledge gap exists in the current understanding of the distribution of these toxic compounds within a localized fire incident response arena. Here, we employ stationary silicone-based passive samplers at controlled live fire trainings to evaluate the deposition behavior of polyaromatic hydrocarbons (PAHs) emitted by fires. Our findings indicate significantly greater total PAH exposure in fires fueled by biomass and wood compared to fires burning cleaner fuels, such as propane. A 22% increase in total PAH deposition and a 68% increase in high molecular weight PAH deposition was recorded for biomass fueled fires compared to propane fueled fires. Furthermore, we observe that heavier molecular weight PAHs exhibit a pronounced deposition front within a certain radius of the hot zone, whereas low molecular weight PAHs are more uniformly distributed throughout the area. These findings highlight that the warm zones and cold zones of fire situations yield elevated levels of carcinogen exposure to first responders within them. We anticipate that these findings will help inform decisions made by emergency personnel when evaluating risk for the hot zone, warm zone, and cold zone of urban fires helping ease the carcinogenic risk experienced.

Evaluation of silicone-based wristbands as passive sampling systems using PAHs as an exposure proxy for carcinogen monitoring in firefighters: Evidence from the firefighter cancer initiative.

Compared to the general population, firefighters are known to sustain greater levels of exposure to hazardous compounds, despite their personal protective equipment, also known as turnout gear. Among the most significant toxins that firefighters are chronically exposed to are polycyclic aromatic hydrocarbons (PAHs). Additionally, firefighters have also been noted to exhibit an increased incidence of certain types of cancer. Considering a probable link between exposure to PAHs and increased rates of cancer in the fire service, we aim to document ambient chemical concentrations in the firefighter work environment. Our strategy involves the use of silicone-based wristbands that have the capacity to passively sorb PAHs. To determine if wristbands can serve as an effective chemical monitoring device for the fire service, silicone wristbands were pilot-tested as personal sampling devices for work environment risk monitoring in active-duty firefighters. Recovered wristbands underwent multiple extraction steps, followed by GC-MS analysis to demonstrate their efficacy in monitoring PAHs in the firefighter environment. Initial findings from all wristband samples taken from firefighters showed multiple exposures to various PAHs of concern for the health of the firefighters when in a fire environment. In addition to PAH monitoring, we examined known and potential sources of PAH contamination in their work environment. To that end, profiles of elevated PAH concentrations were documented at various fire stations throughout South Florida, for individual firefighters both during station duties and active fire response.

Objective Measurement of Carcinogens Among Dominican Republic Firefighters Using Silicone-Based Wristbands.

OBJECTIVE: Characterize objective measurements of carcinogenic exposure using passive sampling silicone-based wristbands among Dominican firefighters. METHODS: Firefighters from a metropolitan fire service in the Dominican Republic were asked to wear a silicone-based wristband during one typical 24-hour shift. A pre- and post-shift survey collected work shift characteristics. Wristbands were processed for the type and quantity of polycyclic aromatic hydrocarbons (PAHs), a family of known carcinogenic compounds. RESULTS: Fifteen firefighters wore a wristband, of which 73.3% responded to a fire with an average of 3.7 calls during the shift. Total PAH exposure was significantly higher among firefighters who responded to a fire versus firefighters with no fire during their shift (261 parts per billion [ppb] vs 117 ppb, P = 0.003). CONCLUSIONS: Silicone-based wristbands as objective passive samplers documented exposure to carcinogenic compounds during a typical 24-hour firefighter shift.

The "Warm Zone" Cases: Environmental Monitoring Immediately Outside the Fire Incident Response Arena by Firefighters.

Hazardous work zones (i.e., hot, warm, and cold) are typically established by emergency response teams during hazardous materials (HAZMAT) calls but less consistently for fire responses to segment personnel and response activities in the immediate geographic area around the fire. Despite national guidelines, studies have documented the inconsistent use of respiratory protective equipment by firefighters at the fire scene. In this case-series report, we describe warm zone gas levels using multigas detectors across five independent fire incident responses all occurring in a large South Florida fire department. Multigas detector data collected at each fire response indicate the presence of sustained levels of volatile organic compounds in the "warm zone" of each fire event. These cases suggest that firefighters should not only implement strategies for multigas detector use within the warm zone but also include respiratory protection to provide adequate safety from toxic exposures in the warm zone.

Hemoglobin aggregates studied under static and dynamic conditions involving the formation of nanobacteria-like structures.

Laser light scattering and scanning electron microscopy (SEM) are used to study hemoglobin in the aqueous phase. The impact that salts [NaCl, Ca3(PO4)2] and iron oxide nanoparticles have on the hemoglobin size are also studied. The first set of experiments examined hemoglobin aggregates in the aqueous phases in the presence of salts and nanoparticles. Aqueous phase samples were then dehydrated and examined using SEM. The resulting structures resemble those observed in nanobacteria studies conducted in other labs. This study demonstrates that aggregates of hemoglobin and various salts found in a physiological environment can produce structures that resemble nanobacteria.