J.D. Skube, Occup. Haz in the Fire Service

Occupational Exposures in the Fire Service 1

Occupational Exposures in the Fire Service
A Review of Exposure and Epidemiological Data
Jonathan D. Skube
Western Kentucky University


Abstract
In the U.S. there are nearly a million firefighters, representing a large workforce that is
exposed to tremendous stressors. In a review of the leading causes of mortality for
firefighters in the U.S., we find both the causes and nature of injury are due to medical
reasons other than trauma. Since investigators first began studying firefighter mortality,
sudden cardiac death has predominated as the largest proportion of on-duty deaths by
cause. Epidemiological studies suggest there is also an increased risk of specific cancers
associated with firefighting as an occupation. Additionally, more recent exposure studies
have shown a variety of combustion byproducts formed by structural fires include
substances known to also contribute to both cancer and cardiovascular disorders. These
substances include microscopic, respirable particles that are essentially invisible to the
eye yet are increased in airborne concentration as fire-suppression activities continue.
Inhalation exposures during fire-suppression are most likely to occur when self-contained
breathing apparatus is not worn. Furthermore, combustion byproducts are found to enter
the body through both dermal and inhalation routes of exposure even while structural-
firefighters’ ensemble is worn, with uptake noted by an increase in the body burden of
carcinogens after exposure. In conclusion, this review of firefighters’ epidemiological
and exposure data may provide evidence that compliance with conventional personal
protection ensembles during all fire-suppression activities are merely minimal exposure
reduction strategies. Lack of respiratory protection during salvage and overhaul
continue to represent a common, yet preventable, cause of potentially life-threatening
exposures. The fire service should be addressed as an occupation where every fire-
suppression activity represents a work environment with specific occupational hazards.


1. Introduction of the Research Topic
1.1 Occupational Exposures in Firefighting
Since the findings of Sir Percival Pott (1744-1788), we have found associations between
occupational exposure to incomplete combustion byproducts and adverse health events
(Richards & Bourgeois, 2014). Since then, environmental and industrial standards have
been established based on scientific discovery and used to make occupations safer by
decreasing the exposure and subsequent risk of an associated illness. However, current
standard operating procedures (SOPs) in the firefighting industry are mainly focused on
the use of structural firefighter's gear as they relate to those working an “active fire” with
visible flames and billowing smoke or in a hazardous materials incident. These
occupational settings describe what we consider an Immediately Dangerous to Life and
Health (IDLH) atmosphere. Until recently, there has been a gross underestimation of the
health impacts that cause firefighter morbidity and mortality, and on atypical firefighter
working environments when compared to fixed-settings in general industry. Minimal
information has been available regarding firefighter exposures during overhaul, the phase
in fire-suppression when firefighters search for hidden fire inside attics, ceilings, and
walls. Additionally, salvage is conducted in an attempt to preserve property. Both
phases are often conducted without the same respiratory protection afforded during the
knockdown phase of an active fire response and any attempted rescue of victims
(Bolsted-Johnson et al., 2000).
Ongoing research is finding more and more constant, insidious threats from both this
work environment and from continuous exposures retained on equipment and especially
on structural firefighters’ protective clothing. Commonly referred to as “bunker” or
“turnout” gear, it serves both as the industry standard and iconic ensemble of a structural
firefighter. Studies suggest there is an apparent lack of any uniform administrative
controls concerning the use of Personal Protective Equipment (PPE), namely, turnout
gear and SCBA. Until recently, the majority of past studies have characterized firefighter
exposures during the knockdown phase, when maximum personal protection is most
often utilized. Lapses in the use of PPE, particularly SCBA, most routinely occur during
lengthy exposure settings that follow active-fire “knockdown”, the phase in fire-
suppression in which the majority of the incident is mitigated. These studies have
indicated that even the act of donning and doffing contaminated PPE can lead to
inhalation of toxic and carcinogenic substances and to the spread of contaminants in the
firehouse (Fent et al., 2014). With nearly 1 million full and part-time firefighters in the
U.S., new research-based regulation and department-based occupational oversight on the
firefighting industry is warranted.
1.2 Current Efforts in Firefighters’ Occupational Health
Since its inception 40 years ago, the National Fire Protection Agency (NFPA) has sought
to primarily protect firefighters against the Immediately Dangerous to Life and Health
(IDLH) atmospheres, in accordance with Occupation Safety and Health Administration
(OSHA) standards (2015). An IDLH atmosphere is defined by the National Institutes for


Occupational Safety and Health (NIOSH) as an atmospheric concentration of any “toxic,
corrosive or asphyxiating substance that poses an immediate threat to life or would cause
irreversible or delayed adverse health effects or would interfere with an individual's
ability to escape from a dangerous atmosphere” (NIOSH, 1994). Since visible flames
and the acutely toxic and heated gasses produced in a fire represent both the most
destructive and acutely hazardous components of a structural fire, IDLH atmosphere,
thermal injuries, and mechanical stressors are at the forefront of industry standards on
firefighter health and safety. However, with the majority of firefighters being well-
trained against immediate threats and thereby preventing life-threatening injuries, there is
apparent lack of training and education towards protecting themselves and each other
against insidious, chronic threats to health that predominate the nature and causes of this
occupation’s mortality rates.
1.3 Firefighter Line of Duty Deaths
According to the NFPA (2015), an on-duty fatality includes “any injury sustained in the
line of duty that proves fatal, any illness that was incurred as a result of actions while on
duty that proves fatal, and fatal mishaps involving non- emergency occupational hazards
that occur while on duty” (Fahy, LeBlanc & Molis, 2015). Commonly referred to as Line
of Duty Deaths (LODDs), these are recorded as incidents when signs and symptoms
occur during firefighting activities, training, or either when enroute or coming back from
a response. Additionally, any illness or injury with initial onset of symptoms and
manifestation during such activities can also been categorized as on-duty fatalities. As an
example, chest pain encountered while on-scene and any subsequent manifestation to a
fatal acute myocardial infarction (AMI) can be included as a case where death is delayed
considerably, even for days.
1.4 Line of Duty Deaths
1.4.1 Sudden Cardiac Death
In a study by the National Fire Protection Agency (NFPA), of the 1,006 total on-duty
firefighter deaths recorded between 1995 and 2005, 440 were attributed to sudden cardiac
death (Fahy, 2005). Of these 440, 155 (35.2 percent) included those who experienced
cardiac symptoms during fire ground operations, with only 3 of them reportedly due to
acute inhalation of smoke. 1 of the 3 acute smoke-related deaths occurred at a “wildland”
(forest) fire setting, where firefighters are not expected, nor commonly equipped, to use
self-contained breathing apparatus (SCBA). The other 2 deaths were at structure fires
where one of the victims was reported to have been using SCBA while stretching a hose
line, a physically strenuous activity, where the face piece may have been dislodged. The
suspected effect of this vigorous activity resulted in the inhalation of toxic gasses either
prior to or while being rescued. The next largest percentage of the 440 cardiac deaths,
111 (25.2%) involved firefighters responding to, or returning from, alarms. Of these
firefighters, 52 were responding to incidents while 59 were returning or had returned
from a response when they appeared to have signs and symptoms of a cardiac event,
constituting a LODD (Fahy, 2005).


1.4.2 Recent Trends in Sudden Cardiac Death
In a more recent study of firefighters in the United States, of the 64 firefighter deaths in
2014, 58% alone were considered related to overexertion, stress and other medical issues,
with 35 of the 37 deaths in this category caused by sudden cardiac death (Fahy, Leblanc
& Molis, 2015). One of these deaths was attributed to an acute ischemic brain incident,
otherwise known as a stroke. Strokes are also designated as a cardiovascular event
because it involves the cardiovascular system. As a whole, sudden cardiac death
accounts for 56% of the total deaths during 2014. Sudden cardiac death rates were higher
for firefighters over the age of 40, constituting more than 2/3 of the total cases (Fahy,
2005).
1.5 Cancer Morbidity and Mortality from Firefighting
As stated by Daniels et al. (2014), most studies have simply examined mortality, but not
cancer incidence, among relatively few firefighters, with subjects recruited from a single
fire department. As of now, instances of fatal cancers possibly resulting from exposure to
firefighting operations are not on the list of on-duty deaths, with numerous discrepancies
noted by the International Association of Fire Fighters (IAFF) in the cancer risk
assessment processes currently used by the National League of Cities (IAFF, 2009).
However, we should expect that this might change in light of studies showing exposure
and quantifiable body burden to both known and suspected carcinogenic substances after
firefighting operations (Fent et al, 2014; Pleil, Stiegel, & Fent, 2014). Shift work, intense
training, and mandatory overnight stays in firehouses, along with high intensity work
during firefighting activities, are viewed as accepted stressors of the trade. However, in
addition to high levels of both physical and emotional stress, it has been recognized by
the IAFF that short and long-term exposure to chemicals and infectious disease are
causes of death and occupational disease disability that might be prevented (IAFF, 2008).
1.5.1 Cancer Rates for Firefighters versus the U.S. General Population
According to LeMasters et al., (2006), in a meta-analysis and systematic review of 32
types of cancer, previous findings of an elevated risk for multiple myeloma were
confirmed to exist among firefighters with a summary risk estimate (SRE) calculated
from existing statistical data. The SRE were calculated after meta-relative risk ratios
were performed on each of the cancer types, with both hypotheses for homogeneity
validated with fixed-effects modeling calculated and verified by SAS statistical software
in a three-part statistical summary, with measures incorporated to control for bias. In
conclusion, the researchers estimated a probable cancer risk of multiple myelomas with
an SRE of 1.53 with a 95% confidence interval (CI) of 1.21-1.94. In addition to eight
cancers possibly associated with firefighting, a probable association with other cancers,
including both non-Hodgkin lymphoma and cancers of the prostate were identified, with
SREs of 1.28 and 1.51, respectively. Testicular cancer had the highest relative risk (RR)
of any cancer identified with firefighting, indicated with a SRE of 2.02 (CI = 1.30-3.13)
(LeMasters et al, 2006).


The results of a study on firefighter exposures and cancer rates by Daniels et al. (2014),
provide additional evidence of a relation between known carcinogens, exposures by
firefighters, and cancer, with findings of excess malignant mesothelioma (SMR 2.00,
95% CI), indicating a twofold increase in mortality from this disease when compared to
the general U.S. population. According to Virta (2006), worldwide asbestos production
and use rose rapidly from 573,728 metric tons in the 1940s to 3,493,800 in 1970. This
fact illustrates the tremendous potential for firefighter exposure to asbestos and
subsequent disease manifestation from exposure during incidents involving buildings
constructed over that time period. This represents a specific workplace hazard generally
minimized for most occupations since the use of asbestos became highly regulated in the
1970s (Fritschi & Glass, 2014). This knowledge is critical to the firefighting industry,
given that asbestos, found in older building where it is integrated into insulating and
fireproofing materials such as concrete, shingles, and around pipes, does not normally
represent an inhalation hazard (Daniels et al., 2014). However, given the nature of
firefighting, any exposures may likely occur during operations in demolished buildings
when asbestos containing materials become damaged and their fibers become airborne.
During this scenario, asbestos fibers may present both inhalation hazards in the air of the
fire-suppression setting and then directly from contaminated structural firefighters gear.
Other diseases recognized to be specific to the respiratory route of exposure are lung
cancers and chronic obstructive pulmonary disease (COPD). These are of interest
because inhalation to the causative agents is considered the major pathway for exposures
during firefighting operations. Additionally, there is evidence of chronic and acute
inflammatory respiratory effects in firefighters. These short-term and chronic exposures
are hypothesized to be linked to the development of cancer (Daniels et al., 2014).
2. Human Exposure to Combustion By-Products
2.1 Environmental Hazards and Public Health Effects
In addition, the World Health Organization (WHO) has established an association
between air pollution and heart health disease, contributing to an estimated 40% of
ischemic heart disease, 40% of strokes, 11% of chronic obstructive pulmonary disease
(COPD), and 6% of lung cancers (World Health Organization, 2014). Additionally,
Jung, Su, & Liang (2015) found an association between indoor air pollutant exposure
with high blood pressure and increased heart rates in subjects according to body mass
index, a suspected factor for heart disease. The study also measured the levels of carbon
dioxide, total volatile organic compounds (VOCs) and PM2.5, two components of a
smoldering fire to which firefighters are certainly exposed. Additionally, in an exposure
and risk assessment performed by Rezadeh Azari et al. (2012), calculated levels of VOCs
in petroleum fuels, included known and/or suspected carcinogens and aromatic toxicants
such as benzene, toluene, ethylbenzene, and xylene (BTEX). Such compounds have been
characterized as being present in aerosol form in both structural fires and during
petroleum fuel loading operations. In the study, the researchers concluded that specific
biomarkers for BTEX compounds were found to accumulate in the bodies of exposed
workers after conducting the loading of petroleum fuel tanker trucks (Rezadeh Azari et
al., 2012).


2.1.1 Health Effects of Volatile Organic Compound (VOC) Exposure
As we now understand, solid or liquid inhalable combustion by-products that enter the
smallest functional components of the human lung consist of aerosolized particles and
other constituents of aerosols that make up smoke. These components include particulate
matter, oxides, volatile organic compounds (VOCs), including potentially toxic and
carcinogenic chemicals and elements (Richards & Bourgois, 2014). Regarding perhaps
the most widely known of the VOCs for its cancer causing properties in the
environmental and occupational environment, benzene is a highly volatile hydrocarbon
that consists of a single, 6-carbon aromatic ring. In a study by Portengen et al. (2015),
even at low levels of benzene exposure, researchers were able to detect increased risk of
lymphopoietic disorders during epidemiological investigations of benzene exposure.
This association was found using a statistical model for calculating exposure levels of
subjects from factories that were part of a nested case-cohort study of benzene exposed
workers (Portengen et al., 2015). This modeling framework enabled us to deal with the
data complexities generally found in studies using historical exposure data in a
comprehensive way and we therefore expect to be able to investigate effects at relatively
low exposure levels, such as those found during sampling as we assess chronic exposures
of firefighters.
2.1.2 Health Effects of Particulate Matter
In population health studies, industrialized nations have gained awareness of associations
between increases in the concentration of airborne combustion by-products and a
corresponding increase in adverse human health effects. In particular, urbanized centers
have become centers of environmental health research into the effects of particulate
matter on human health. Of special importance, particulate matter with an average
aerodynamic diameter equal to or less than 2.5 micrometers (PM2.5) has been implicated
in both respiratory and cardiovascular diseases, including strokes, heart disease, and
cancer, due to its ability to enter and carry compounds and elements to the smallest
regions of the human respiratory system (Richards & Bourgois, 2014). As one of the
most polluted cities in the world, Beijing has observed various adverse health
consequences from airborne contaminants, including PM2.5, which has resulted in both
increases in respiratory disease incidence and severity, with excessive hospital
admissions correlated with increased airborne concentration of these pollutants (Xiong et
al., 2015). In a study by Lee, Coull, Kloog, & Schwartz (2015) on the acute effects of
inhalation particulate matter, 10  mcg/m3
increase in PM2.5 was associated with a 1.56%
increase in daily deaths, with increases in cardiovascular disease showing the highest
effect estimate. Orru et al. (2009) found a relationship between the airborne
concentration of fine particulate matter and cardiovascular events, leading to both an
increased number of hospitalizations and premature deaths, as indicated by a decrease in
life expectancy of as much as an estimated 13 years.


2.2 Occupational Hazards and Health Effects from Firefighting
According to the NFPA, there were 346,000 career firefighters and 783,000 volunteer
firefighters in the USA between 2012 and 2013; any number of which were exposed to a
potential variety of chemicals and particulates during fire suppression, including
components of incomplete combustion that can exist in both particle and gas phase
(Karter & Stein, 2013). According to Feairheller (2015), high blood pressure,
cardiovascular disease (CVD), and obesity are global health problems and are a large
concern for firefighters, with the leading cause of death among firefighters being cardiac-
related. These threats to health, while at the center stage in our nation’s public health
view, may be of great concern to first responders and especially firefighters, as they face
austere and dangerous environments daily. However, such obvious threats as injury or
death from building collapse, inhalation of acutely toxic smoke, and burns are most
predominantly the concern among firefighters since first being addressed on a national
scale with the release of the first and most predominant NFPA publication on safety,
NFPA 1950. While such publications serve as essential components to the field,
immediate threats to life safety overwhelmingly have had the spotlight over firefighter
long-term health and wellbeing (Feairheller, 2015).
In a study by Fent et al. (2015), there was a measured >5 fold increases in mean
concentrations of styrene, benzene, 1,4-dichlorobenzene, acetone, and cyclohexane in the
burn site collected after a controlled burn, when compared to background atmospheric
concentrations. In addition, the researchers measured >2 fold increases in mean breath
concentrations of benzene, toluene, and styrene after the burns when compared to pre-
exposure samples. In conclusion, it was found that BTEX compounds “off-gassing” from
firefighters' used PPE and in firefighters' post-burn exhaled breath were significantly
correlated (Fent et al., 2015). Additionally, Trasande et al. (2015), found that polycyclic
aromatic hydrocarbons (PAH), commonly are produced by incomplete combustion
processes, have been associated with oxidant stress as well as insulin resistance and
hypertension in adults. By providing direct toxicological information into some of the
occupational risk factors for heart disease, it may be equally critical to protect from
obvious examples of acute hazards as it is to understand how firefighters’ personal
protective equipment (PPE) affects cardiovascular responses as risks to as long-term
health.
3. Protection Against Exposure and Physical Stressors
3.1 Firefighting Industry Standards – Turnout Gear
The NFPA, while responsible for producing a library of PPE standards for the fire
service, is also responsible for setting the industry standards that provide atmospheric
protection for the body of first responders during firefighting and hazardous materials
operations. NFPA 1971 details specifications and uses for PPE ensembles for structural
firefighting (NFPA, 2013). Turnout gear, most characteristic of firefighting operations,
consists of a jacket and pant set, with at least an abrasion and heat resistant outer layer, a
water-resistant yet vapor-permeable middle inner layer, and an additional heat-resistant


liner. The design of the suits is to allow for maximum thermal and physical hazard
protection and dexterity during any active-fire response, with materials technology that
allows the liquid barrier layer to keep firefighters dry from water but to allow for gaseous
perspiration to leave the suit. For such reasons, turnout gear is not to be used for
response to Chemical, Biological, Radiological, or Nuclear (CBRN) threats (NFPA,
2013).
3.2 Turnout Gear versus Vapor-Protective Ensembles
Turnout gear, in its most predominantly implemented forms, is neither impervious to
vaporous hazards nor dermal exposures to soot and chemicals that may come in direct
contact with skin, as obvious gaps exist between the suit, the gloves, and the SCBA face-
piece (NFPA, 2013). This comes despite built-in features that include a thumb loop and
cuffing between the sleeve and any removable gloves worn. Additionally, there is the
incorporation of a separate thermal protective hood that is worn over the facemask seal
and under the collar of the jacket. Despite the seemingly comprehensive coverage of this
ensemble design, these areas can become quickly compromised during stressful incidents
where flesh may be directly exposed the surrounding environment. In contrast, the
standards for structural and proximity firefighting vary significantly from the NFPA 1991
Standard on Vapor-Protective Ensamples for Hazardous Materials Emergencies, which
details the Level A ensemble – a fully-encapsulating, one-piece suit that provides the
maximum barrier from both liquid and aerosolized hazards (NFPA, 2005). This suit type
is in direct contrast with turnout-gear as any suspected gaps that would allow even vapor
penetration are taped or otherwise sealed according to manufacturers’ instructions. Like
turnout gear, Level A suits are also worn in conjunction with SCBA. However, the
vapor-barrier enable provides essentially no thermal protection and cannot be used in
firefighting operations where flame hazards exist or are likely to occur. This becomes one
of the main disadvantage to the Level A suit as perspiration readily accumulates in the
suit, often limiting visibility. Additionally, lack of thermal protection and vapor
permeability make both heat stress and cold weather effects more likely than those
wearing turnout gear (NFPA, 2005).
3.2.1 Protective Limitations of Turnout Gear
Testing of firefighters for the presence of toxicants (clinical biomarkers) by taking
samples of exhaled breath for lab analysis, is suggested as a suitable method for assessing
systemic dermal exposure in a simple and non-invasive manner, when we assume that
SCBA, when worn during operations, is fully effective during firefighting operations
(Fent et al, 2014). According to Kirk et al. (2011), combustion science investigators
researching the gaseous components of structural fires found that aromatic hydrocarbons,
common components of incomplete combustion, may penetrate turnout gear and come in
direct contact with skin (Fent et al, 2014). In addition, samples of firefighter face and
neck wipes taken after “controlled burns” of household fires were found to contain a
number of Polyaromatic Hydrocarbons (PAHs) and single ring organic compounds,
several of which are known to have carcinogenic activity. Additionally, Baxter et al.


(2014), found both benzene and benzofluoranthene, category 1 and category 2
carcinogens, in overhaul air from samples taken during controlled burn trials (Baxter et
al., 2014; NIOSH, 2015). While Pleil, Stiegel, & Fent (2014) assumed that SCBA
protects the user from the majority of inhaled hydrocarbons, any changes in the exhaled
profile of combustion products, including an increase in post-exposure bio-assessment for
both single ring and poly aromatic hydrocarbons found, can be attributed to dermal
exposures from gas and particle penetration through the turnout gear.
3.3 Self-Contained Breathing Apparatus and Limitations
As assumed by the aforementioned study by Pleil, Stiegel, & Fent (2014), SCBA, which
is afforded the maximum Protection Factor (PF) by the National Institute for
Occupational Safety and Health (NIOSH) of any respiratory protection device, should
keep the respiratory tract protected by maintaining positive pressure between the seal of
the mask and the face of operator under normal exertion levels. However, according to a
study of firefighters’ use of SCBA during various physical activities by Burgess &
Crutchfield (1995), under higher levels of physical stress, firefighters could “over-
breathe” SCBA, causing a break between the skin and full facemask of the operator
(Pleil, Stiegel, & Fent, 2014). The results of the break between the facemask and
operator was the inhalation of the surrounding atmosphere, thereby confirming the
potential for inhalation of any toxic and/or carcinogenic aerosols contained therein to
enter the users’ respiratory tract. This was found to be due to overcoming the allotted
rate and amount of supplied air at a given time (Fent et al., 2014). Thus, for every
firefighter that encounters excessive exertion levels, it may be assumed that there is
potential for a significant toxic and/or carcinogenic inhalation exposure to occur in other
than “normal levels of exertion” (Burgess & Crutchfield, 1995).
4. Exposures Encountered during Fire Suppression Activities
4.1 Dermal Exposures during Firefighting
The composition of structural firefighters PPE typically includes layers that are easily
permeated by aerosolized particles, as they are meant to reduce thermal and physical
hazards while providing liquid-resistant, yet breathable protection, by allowing for gas
exchange. Until recently, only a few studies have explored dermal exposure and
absorption of combustion products in firefighters (Fent et al., 2014). During a study of
dermal absorption of aromatic hydrocarbons by both firefighters and fuel workers, the
authors concluded that there was significant increases in breath concentrations of benzene
that were consistent with levels of contaminant accumulated on the face and neck –
portions of the body only protected by a thin fabric hood, despite the use of appropriate
respiratory protection, including SCBA, for firefighters in the study (Pleil, Stiegel, &
Fent, 2014). This study was representative of real-world scenarios whereby firefighters
and fuel-workers both wore job appropriate PPE. In an attempt to limit the inhalation
route of exposure during the live-fire study, participating firefighters wore SCBA
throughout operations and stayed upwind of the site after doffing ensemble at a distance
of at least 30 meters from the structure. The authors of the study conclude that while


controlling for inhalation exposure as best as possible, exposure to environmental smoke
from premature removal of SCBA and transfer of PAHs from contaminated gear to the
skin were potential confounders of the study. In conclusion, it was found that firefighters
wearing full protective ensembles have systemic uptake of PAHs and other aromatic
hydrocarbons, with the neck being the primary site of exposure (figure 1). Thus, further
study on hood design, turnout gear doffing, decontamination methods, and growing
awareness of firefighters’ dermal absorption during fire responses are warranted (Pleil,
Stiegel, & Fent, 2014).
Figure 1: Pre and Post-Exposure Breath Concentration of Select Hydrocarbons for
Firefighters and U.S. Air Force Fuel Workers
Referenced from: Pleil, Stiegel, & Fent, 2014
4.2 Inhalation Exposures during Fire Suppression Activities
In a study by Baxter et al. (2010), fine particulate matter was measured in 7 different
scale scenarios, including 90 minutes prior to ignition, during initial fire ignition, initial
fire-suppression (knockdown), and during salvage and overhaul. The researchers found
that ultrafine particulate matter (<1 micrometer in diameter) were generated at high
number densities relative to background values, beginning at the knockdown and even
more so at the overhaul stages. In all scenarios, including automobile fires and differing
residential setups, ultrafine particulate matter was found to comprise greater than 99% of
the total particulate matter measured using a wide range particle spectrometer (figure 2).
While not visible to the naked eye, it is hypothesized that ultrafine particles generated
during knockdown and overhaul may give firefighters a false sense of security and easily
lead to doffing of SCBA prematurely. Exposure to ultrafine particulate matter is


suspected to contribute to the incidence of both cardiovascular disease and sudden
cardiac death. During physical examinations, clinical changes in both spirometry and
other lung permeability parameters in firefighters noted as not wearing SCBA during
overhaul have been documented (Baxter et al., 2010).
Figure 2: Particulate Matter Sampled during Fire Suppression Activities
Referenced from: Baxter et al., 2010
4.3 Mixed Inhalation/Dermal Uptake of VOCs during Fire Suppression
In summary of a study of firefighters by Fent et al. (2014), after controlling for inhalation
route of entry by continued use of SCBA during doffing of structural firefighters
equipment, the authors noted that after finding for clinical biomarkers, it was concluded
that the PAHs most likely entered firefighters’ bodies through their skin. In a subsequent
study by Fent et al. (2015), there was a measured >5 fold increases in mean
concentrations of styrene, benzene, 1,4-dichlorobenzene, acetone, and cyclohexane in the
burn site collected following a controlled burn, when compared to background levels. In
support of both dermal and inhalation routes of exposure as significant to the uptake of
VOCs, a subsequent study of the dermal route of exposure concluded that a more than
two-fold increase in mean breath concentrations of benzene, toluene, and styrene were
present in samples taken from firefighters after the burns, when compared to pre-
exposure samples. In addition, the concentrations of BTEX chemicals measured off-
gassing from firefighters' used PPE and in firefighters' post-burn exhaled breath were
significantly correlated. In this case, the authors conceded that although previous studies
have suggested a single route of exposure to be the culprit for the majority of systemic
contaminants, firefighters might have absorbed these substances through both the dermal
and (to a lesser extent) inhalation routes during firefighting and from off-gassing of
contaminated tools, equipment, and PPE after fire-suppression operations (Fent et al.,
2015).
4.4 Exposures in the Firehouse
In addition to exposures during fire-suppression activities, it has been found that the
firehouse contributes to airborne contamination in the firefighters’ living environment. In


an exposure study of particulate matter comparing both fire-suppression sites and
firehouses, both environments were found to contain significant airborne contamination
of particulate matter and other combustion byproducts. In a typical firefighting shift, 24
hours constitutes the typical timeframe that a crew works, with 48 hours between shifts.
The result is that exposures in the workplace, to include the firehouse, may involve a
more continuous exposure of occupational exposures, well beyond the timeframes that
NIOSH and the Occupational Safety and Health Administration (OSHA) standards make
provisions for, based on typical 8 and 10-hour workdays. This makes the estimation of
both recommended and regulatory limits of exposure to contaminants difficult, with gross
underestimation of workplace exposures of particular concern. The results of the study by
Baxter et al. (2014) conclude that detectable exposures to particulate matter in the
respirable range contaminate both the sites where firefighting activities occur and
additionally in parts of the firehouse where cooking, dining, storage, training, and other
work activities commonly take place. Contaminated areas inside the firehouse include
vehicle-bays, sleeping quarters, and kitchens where air samples containing both PM2.5
and submicron particles were found (figure 3). Furthermore, the researchers found
PAHs, including naphthalene, present in 2 out of 3 firehouses where samples were taken
(Baxter et al, 2014). Therefore, in addition to airborne exposure, toxic and/or
carcinogenic substances may also be present in the food and drink preparation areas,
providing the potential for the ingestion route of exposure from the food the firefighters
consume while on duty.
Figure 3: Fine Particle Concentration in the Firehouse over Time of Day
Referenced from: Baxter et al, 2014.#
5. Conclusion
As a series of future steps, illustrated by Fent et al. (2014), adherence to wearing full
protective ensembles, research on further study designs on PPE including redesign of fire
-resistant hoods, and methods of decontamination as well as ways to otherwise limit
firefighters’ dermal absorption of toxic and/or carcinogenic substances, are all minimal
steps to reduce the frequency, extent, and duration of future exposures in this occupation.
New NFPA standards for turnout gear include specifics on cleaning and maintaining


existing gear prior to and following exposure to fire and combustion byproducts, as both
SCBA and PPE are noted to be both critical to the job and an important part of a
firefighter’s protection against exposure to carcinogens (NFPA, 2015). However, the
responsibility for compliance lies with both individual departments and firefighters to
ensure PPE and SCBA are maintained and cleaned as recommended by the NFPA. In
light of recent research and exposure data that illustrates the insidious hazards we now
recognize as threats to both life and health, it is their responsibility to ensure that SCBA
is worn during all fire-suppression phases, including salvage and overhaul. Additionally,
firefighters should be made aware of the potential for inhalation exposure when doffing
and traveling in confined vehicles with contaminated PPE and take measures to minimize
this exposure pathway (Fent et al., 2015). As we have observed more information on
toxic and/or carcinogenic substances encountered during and after fire-suppression, the
industry should seek to improve administrative controls through compliance with
firefighters’ protection against exposure to toxic and carcinogenic substances with the
implementation and take initiatives to continually strive for the development of new PPE.
Finally, fire departments should invest in the components of workplace hazard reduction
and utilize industrial hygienists, occupational health physicians, and other environmental
health and safety personnel for monitoring of contaminants in both fire-suppression sites
and the firehouse.


Sources Cited
Baxter, C.S., Ross, C.S., Fabian, T., Jacob, L. Borgerson, J.L., Shawdon, J., Gandhi,
P.D., Dalton, J.M., MArch & Lockey, J.E. (2010). Ultrafine particle exposure
during fire suppression – is it an important contributory factor for coronary heart
disease in firefighters? American College of Occupational and Environmental
Medicine (JOEM). 2010 Aug;52(8).
Referenced from:
http://media.cygnus.com/files/cygnus/article/FHC/2010/SEP/firefightersandheartd
isease_10466452.pdf
Baxter, C.S., Hoffman, J.D., Knipp, M.J., Reponen, T., & Haynes, E.N. (2014). Exposure
of firefighters to particulates and polycyclic aromatic hydrocarbons. Occup
Environ Hyg. 2014;11(7):D85-91. doi: 10.1080/15459624.2014.890286.
Referenced from:
http://www.ncbi.nlm.nih.gov/pubmed/24512044
Bolstad-Johnson, D.M., Burgess, J.L., Crutchfield, C.D., Storment, S., Gerkin, R.,
Wilson, J.R. (2000). Characterization of firefighter exposures during fire
overhaul. AIHAJ. 2000 Sep-Oct;61(5):636-41.
Referenced from:
Burgess JL, Crutchfield CD. (1995). Quantitative respirator fit tests of Tucson fire
fighters and measurement of negative pressure excursions during exertion. Appl
Occup Environ Hyg; 10: 29–36
Referenced from:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4124999/#CIT0005
Daniels, R., Kubale, T., Tiin, J, Dahm, M., Hales, T., Baris, D., Zahm, S., Beaumont, J.,
Waters, K. & Pinkerton, L. (2014). Mortality and cancer incidence in a pooled
cohort of US firefighters from san francisco, chicago, and Philadelphia (1950-
2009). Occup Environ Med. 2014 Jun; 71(6): 388–397.
Published online 2013 Oct 14.
Referenced from:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4499779/
Fahy, R.F. (2005). U.S. Firefighter Fatalities Due to Sudden Cardiac Death, 1995 –
2004. Quincy, MA; National Fire Protection Association Fire Analysis and
Research Division.
Fahy, R.F., LeBlanc, P.R., Molis, J.L. (2015). Firefighter Fatalities in the United States
– 2014. Quincy, MA; National Fire Protection Association Fire Analysis and
Research Division.
Feairheller, D.L. (2015). Blood pressure and heart rate responses in volunteer
firefighters while wearing personal protective equipment. Blood Press Monit.


2015 Aug;20(4):194-8. doi: 10.1097/MBP.0000000000000120.
Referenced from:
Fent, K.W., Eisenberg, J., Snawder, J., Sammons, D., Pleil, J.D., Stiegel, M.A., Mueller,
C., Horn, G.P., & Dalton, J. (2014). Systemic exposure to PAHs and benzene in
firefighters suppressing controlled structure fires. Ann Occup Hyg. 2014 Aug;
58(7): 830–845.
Referenced from:
Fent, K.W., Evans, D.E., Booher, D., Pleil, J.D., Stiegel, M.A., Horn, G.P., Dalton, J.
(2015). Volatile Organic Compounds Off-gassing from Firefighters' Personal
Protective Equipment Ensembles after Use. J Occup Environ Hyg.
2015;12(6):404-14. doi: 10.1080/15459624.2015.1025135.
Retrieved from:
Fritschi, L., Glass, D.C. (2014). Firefighters and cancer: where are we and where to
now?. Occup Environ Med. 2014;71(8):525-526.
Referenced from:
http://www.medscape.com/viewarticle/828495
International Association of Fire Fighters [IAFF]. (2008). The Fire Service Joint Labor
Management Wellness-Fitness Initiative (3rd
ed.).
Referenced from:
http://www.iafc.org/files/healthWell_WFI3rdEdition.pdf.pdf
International Association of Fire Chiefs [IAFC]. (2009). Review and assessment of the
national league of cities’ assessing cancer presumption laws and current
firefighter cancer research.
Referenced from:
https://www.iafc.org/files/safety_ReviewFindingsNLCreportOnCancerRiskInFire
fighters.pdf
Jung, C.C., Su, H.J., & Liang, H.H. (2015). Association between indoor air pollutant
exposure and blood pressure and heart rate in subjects according to body mass
index. Sci Total Environ. 2015 Sep 9;539:271-276. doi:
10.1016/j.scitotenv.2015.08.158.
Referenced from:
http://www.ncbi.nlm.nih.gov/pubmed/?term=Jung%2C+C.C.%2C+Su%2C+H.J.
%2C+%26+Liang%2C+H.H.++%282015%29.++Association+between+indoor+a
ir+pollutant+exposure+and+blood+pressure+and+heart+rate+in+subjects+accordi
ng+to+body+mass+index.++Sci+Total+Environ.+2015+Sep+9%3B539%3A271-
276.+doi%3A+10.1016%2Fj.scitotenv.2015.08.158.++Referenced+from%3A


Karter, M.J. & Stein, G.P (eds). (2013). U.S. Fire Department Profile (2013a). Quincy,
MA: National Fire Protection Association.
Referenced from:
Kirk, K.M., Ridgway, M., Splawinski, Z., & Logan, M.B. (eds). (2011). Firefighter
exposures to airborne contaminants during extinguishment of simulated
residential room fires, Research Report 2011-01. Queensland, Australia:
Queensland Fire Rescue Service Scientific Branch.
Referenced from:
Lee, M., Koutrakis, P., Coull, B., Kloog, I., & Schwartz, J. Acute effect of fine
particulate matter on mortality in three Southeastern states from 2007-2011. J
Expo Sci Environ Epidemiol. 2015 Aug 26. doi: 10.1038/jes.2015.47.
Referenced from:
LeMasters, G.K., Geniady, A.M., Succop, P., Deddens, J., Sobeih, T., Berriera-Viruet,
H., Dunning, K., & Lockey, K. (2006). Cancer risk among firefighters: a review
and meta-analysis of 32 studies. J Occup Environ Med. 2006 Nov;48(11):1189-
202.
Referenced from:
https://www.iaff.org/hs/PDF/Cancer%20Risk%20Among%20Firefighters%20-
%20UC%20Study.pdf
Lim, S.K., Shin, H.S., Yoon, K.S., Kwack, S.J., Um, Y.M., Hyeon, J.H., Kwak, H.M.,
Kim, J.Y., Kim, T.Y., Kim, Y.J., Roh, T.H., Lim, D.S., Shin, M.K., Choi, S.M.,
Kim, H.S., & Lee, B.B. (2015) Risk assessment of volatile organic compounds
benzene, toluene, ethylbenzene, and xylene (BTEX) in consumer products. J
Toxicol Environ Health A. 2014;77(22-24):1502-21. doi:
10.1080/15287394.2014.955905.
Referenced from:
National Institutes for Occupational Safety and Health [NIOSH]. (2015).
Benzofluoroanthene. International Chemical Safety Cards (ICSC).
Referenced from:
http://www.cdc.gov/niosh/ipcsneng/neng0720.html
National Fire Protection Agency [NFPA]. Firefighter fatalities in the United States -
2014. Quincy, MA.
Referenced from:
http://www.nfpa.org/research/reports-and-statistics/the-fire-service/fatalities-and-
injuries/firefighter-fatalities-in-the-united-states


National Fire Protection Agency [NFPA]. (2005). NFPA 1991, Standard on Vapor-
Protective Ensamples for Hazardous Materials Emergencies – 2005 Edition.
Quincy, MA.
National Fire Protection Agency [NFPA]. (2013). NFPA 1971, Protective Ensembles for
Structural Fire Fighting and Proximity Fire Fighting – 2013 Edition. Quincy,
MA.
National Fire Protection Agency [NFPA]. (2014). NFPA 1851, Standard on Selection,
Care and Maintenance of Protective Ensembles for Structural Fire Fighting and
Proximity Fire Fighting – 2014 Edition. Quincy, MA.
National Institutes for Occupational Safety and Health [NIOSH]. (1994). Immediately
Dangerous To Life or Health (IDLH).
Retrieved from: http://www.cdc.gov/niosh/idlh/idlhintr.html
Orru, H., Teinemaa, E., Lai, Taavi, L., Tamm, T., Kassik, M., Kimmel, V., Kangur, K.,
Merisalu, E., & Forsberg, B. (2009). Health impact assessment of particulate
pollution in Tallinn using fine spatial resolution and modeling techniques.
Environ Health. 2009; 8: 7. Published online 2009 Mar 3. doi: 10.1186/1476-
069X-8-7.
Referenced from:
Pleil, J.D., Stiegel, M.A., & Fent, K.W. (2014). Exploratory breath analyses for
assessing toxic dermal exposures of firefighters during suppression of structural
burns. J Breath Res. 2014 Sep;8(3):037107. doi: 10.1088/1752-7155/8/3/037107.
Epub 2014 Sep 4.
Referenced from:
Portengen, L., Linet, M.S., Li, G.L., Lan, Q., Dores, G.M., B.T., Hayes, R.B., Yin S.N.,
Rothman, N., & Vermeulen, R. (2015). Retrospective benzene exposure
assessment for a multi-center case-cohort study of benzene-exposed workers in
China. J Expo Sci Environ Epidemiol. 2015 Aug 12. doi: 10.1038/jes.2015.44.
Referenced from:
Richards, I.S., & Bourgeois, M. (2014). Principles and Practices of Toxicology in
Public Health (2nd
ed). Burlington, MA: Jones and Bartlett Learning.
Trasande, L., Urbina, E.M., Kohder, M., Alghamadi, M., Shabaj, I. Alam, M.S., Harrison,
R.M., & Shamy, M. (2015). Polycyclic aromatic hydrocarbons, brachial artery
distensibility and blood pressure among children residing near an oil refinery.


Environ Res. 2015 Jan;136:133-40. doi: 10.1016/j.envres.2014.08.038. Epub
2014 Nov 20.
Referenced from:
Virta, R.L. (2006). Worldwide asbestos supply and consumption trends from 1900
through 2003. U.S. Department of the Interior (USGS): Reston, Virginia.
Referenced from:
http://pubs.usgs.gov/circ/2006/1298/c1298.pdf
Willette, K. (2015). The Exposure Factor: Firefighting, Hazardous Environments and
NFPA Standards. National Fire Protection Association Journal; May 1, 2015.
Retrieved from:
http://www.nfpa.org/newsandpublications/nfpa-journal/2015/may-june-
2015/columns/first-responder

World Health Organization [WHO]. (2014). 7 million premature deaths annually linked
to air pollution. WHO; Geneva, Switzerland. 25 March 2014
Referenced by:
http://www.who.int/mediacentre/news/releases/2014/air-pollution/en/
Xiong, Q., Zhao, W., Gong, Z., Zhao, W., & Tang, T. (2015). Fine Particulate Matter
Pollution and Hospital Admissions for Respiratory Diseases in Beijing, China. Int
J Environ Res Public Health. 2015 Sep 22;12(9):11880-11892.
Referenced from:

J.D. Skube, Occup. Haz in the Fire Service

Recommandé

Recommandé

Contenu connexe

En vedette

En vedette (18)

Similaire à J.D. Skube, Occup. Haz in the Fire Service

Similaire à J.D. Skube, Occup. Haz in the Fire Service (20)

J.D. Skube, Occup. Haz in the Fire Service