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.
•Firefighters are occupationally exposed to toxic and carcinogenic compounds such as polyaromatic hydrocarbons (PAHs).•Silicone-based passive sampling presents an easy, affordable means to document firefighter exposure.•PAH exposure observed on wristbands of firefighters reporting to fire scenes was greater than for non-fire wristbands.•Diagnostic PAH ratios support exposure originating from diesel combustion observed in the fire service environment.
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.
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.
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.
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.
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.
•Fire investigators are exposed to carcinogens while performing post-fire audits.•Fire investigators’ polyaromatic hydrocarbon exposures were evaluated with silicone wristbands.•Newer post-fire scenes yield higher exposures than older ones.•Exposure results suggest a need for protection from vapor-phase contaminants.•This is the first study to evaluate investigators’ exposures at post-fire scenes.
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.
•Firefighters are occupationally exposed to toxic and carcinogenic compounds during various fire situations.•Fire scenes are divided into safety zones: hot zones, warm zones, and cold zones.•This work assesses the migration and deposition of volatilized carcinogens such as PAHs in fire situations and the surrounding environment.•Passive samplers highlight higher than anticipated PAH levels in various zones at a fire scene.•Provide insights to help with policies to mitigate future exposure for firefighters and the nearby population.
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.
Metoda dinamičkog rasapa svjetlosti i pretražna elektronska mikroskopija (SEM) koriš tene su za proučavanje hemoglobina u vodenoj fazi. Nadalje, ispitivan je utjecaj soli NaCl, Ca3(PO4)2 i nanočestica oksida željeza na veličinu hemoglobina. U prvom setu pokusa proučavani su agregati hemoglobina u vodenoj fazi u prisutnosti soli i nanočestica. Vodena faza je dehidrirana i ostatak analiziran pomoću pretražne elektronske mikroskopije. Agregati hemoglobina i različitih soli pronađeni u fiziološkim uvjetima čine strukture slične nanobakterijama.
Metoda dinamičkog rasapa svjetlosti i pretražna elektronska mikroskopija (SEM) korištene su za proučavanje hemoglobina u vodenoj fazi. Nadalje, ispitivan je utjecaj soli NaCl, Ca3(PO4)2 i ...nanočestica oksida željeza na veličinu hemoglobina. U prvom setu pokusa proučavani su agregati hemoglobina u vodenoj fazi u prisutnosti soli i nanočestica. Vodena faza je dehidrirana i ostatak analiziran pomoću pretražne elektronske mikroskopije. Agregati hemoglobina i različitih soli pronađeni u fiziološkim uvjetima čine strukture slične nanobakterijama.
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