Respiratory function in active firefighters

The allostatic load model: a framework to understand the cumulative multi-system impact of work-related psychosocial stress exposure among firefighters

Firefighting is recognised as a profession where health and well-being can be affected by a variety of occupational factors, such as physical, thermal, and chemical stressors. Along with the risks intuitively associated with the fire service, however, psychosocial stress has begun to attract attention as another variable deserving of consideration. Indeed, long-term exposure to work-related psychosocial stress has been linked with poor health outcomes in many workers; however, despite this association, very little has been done to examine how such stressors become biologically embedded in firefighters. To help facilitate research into how psychosocial stress can affect health-related outcomes in the fire service, we propose a framework centered on the notion of allostatic load. First, we reviewed the occupational characteristics that may generate psychosocial stress within firefighters before introducing allostatic load (that is, dysregulation across various physiological systems caused by the need to manage ongoing stressors). Next, we provided a summary of how allostatic load can be measured and touched on the framework's utility for studying the cumulative effects of work-related stress on firefighter health. After this, factors that may influence the steps leading from stress exposure to health outcomes were discussed; in particular, we commented upon how research in this area should consider specific non-modifiable (age, sex, and ethnicity) and modifiable (psychosocial resources and behavioural habits) factors. Finally, we presented methodological barriers and opportunities that may arise when using the allostatic load framework with this professional group. By introducing the framework, we hope to provide a tool that may be used by those interested in stress-health research in firefighters to build the evidence needed to inform primary prevention measures.

Bench-Scale and Full-Scale Level Evaluation of the Effect of Parameters on Cleaning Efficacy of the Firefighters' PPE

The National Fire Protection Association (NFPA) 1851 document provides guidelines for firefighters on the care and maintenance of their PPE, including decontamination practices. Firefighters are exposed to various toxic chemicals during fire suppression activities, making effective decontamination crucial for their safety. This study evaluated the efficacy of different washing parameters, including temperature, time, and surfactants, on cleaning outer-shell material contaminated with nine targeted compounds from three different functional groups: phenols, polycyclic aromatic hydrocarbons (PAHs), and phthalates. The study was conducted on both bench-scale and full-scale levels, with contaminated swatches washed in a water shaker bath in the bench-scale evaluation and full-sized washer extractors used in the full-scale evaluation. The results showed that bench-scale washing demonstrated similar trends in contaminant removal to full-scale washing. Importantly, the study highlighted the complexity of removing fireground contaminants from the personal protective ensemble (PPE). The findings of this study have practical implications for the firefighting industry as they provide insight into the effectiveness of different washing parameters for PPE decontamination. Future studies could explore the impact of repeated washing on PPE and investigate the potential for developing more efficient decontamination strategies. Ultimately, the study underscores the importance of ongoing efforts to ensure the safety of firefighters, who face significant occupational hazards.

Comparing self-reported obstructive airway disease in firefighters with and without World Trade Center exposure

BACKGROUND

The degree to which routine, non-World Trade Center (WTC) firefighting exposures contribute to the WTC exposure-obstructive airway disease (OAD) relationship is unknown. Our objective was to compare the frequency of self-reported OAD diagnoses in WTC-exposed firefighters from the Fire Department of the City of New York (FDNY) compared with non-WTC-exposed firefighters from other cities and the general population.

METHODS

A total of 9792 WTC-exposed male FDNY firefighters and 3138 non-WTC-exposed male firefighters from Chicago, Philadelphia, and San Francisco who were actively employed on 9/11/01 and completed a health questionnaire were included. Logistic regression estimated odds ratios of self-reported asthma and COPD diagnoses in firefighters (WTC-exposed vs. non-WTC-exposed; all firefighters vs. general population), adjusting for age, race, smoking status, and last medical visit.

RESULTS

WTC-exposed firefighters were, on average, younger on 9/11 (mean ± SD = 40.2 ± 7.4 vs. 44.1 ± 9.1) and less likely to report ever-smoking (32.9% vs. 41.8%) than non-WTC-exposed firefighters. Odds of any OAD and asthma were 4.5 and 6.3 times greater, respectively, in WTC-exposed versus non-WTC-exposed. Odds of COPD were also greater in WTC-exposed versus non-WTC-exposed, particularly among never-smokers. Compared with the general population, WTC-exposed firefighters had greater odds of both asthma and COPD, while the nonexposed had lower odds of asthma and greater odds of COPD.

CONCLUSIONS

Odds ratios for OAD diagnoses were greater in WTC-exposed firefighters versus both non-WTC-exposed and the general population after adjusting for covariates. While asthma and other OADs are known occupational hazards of firefighting, WTC exposure significantly compounded these adverse respiratory effects.

The Effect of Fire Smoke Exposure on Firefighters' Lung Function: A Meta-Analysis

Firefighters are exposed to a range of harmful substances during firefighting. Exposure to fire smoke has been associated with a decrease in their lung function. However, the cause-effect relationship between those two factors is not yet demonstrated. This meta-analysis aimed to evaluate the potential associations between firefighters' occupational exposure and their lung function deterioration. Studies were identified from PubMed, Web of Science, Scopus and Science Direct databases (August 1990-March 2021). The studies were included when reporting the lung function values of Forced Expiratory Volume in 1 s (FEV₁) or Forced Vital Capacity (FVC). The meta-analyses were performed using the generic inverse variance in R software with a random-effects model. Subgroup analysis was used to determine if the lung function was influenced by a potential study effect or by the participants' characteristics. A total of 5562 participants from 24 studies were included. No significant difference was found between firefighters' predicted FEV₁ from wildland, 97.64% (95% CI: 91.45-103.82%; I² = 99%), and urban fires, 99.71% (95% CI: 96.75-102.67%; I² = 98%). Similar results were found for the predicted FVC. Nevertheless, the mean values of firefighters' predicted lung function varied significantly among studies, suggesting many confounders, such as trials' design, statistical methods, methodologies applied, firefighters' daily exposure and career length, hindering an appropriate comparison between the studies.

Assessment and outcomes of firefighter applicants with possible asthma

BACKGROUND

Firefighter applicants (FFAs) with a history of asthma may be refused entry to the fire service because of potentially putting themselves and others at risk.

AIMS

We undertook a service evaluation to identify respiratory and employment outcomes of FFAs with a history of asthma who had undergone additional respiratory assessment at our specialist occupational lung disease clinic during 2005-19.

METHODS

We reviewed FFA medical records and categorized them as having either no current asthma or definite/probable asthma at the time of clinic assessment. 'No current asthma' was defined as negative non-specific bronchial hyper-responsiveness (BHR) to histamine/methacholine, and no symptoms or treatment within the 2 years before clinic. 'Definite/probable current asthma' was defined as either positive BHR, or negative BHR with symptoms and/or treatment within the previous 2 years. Around 1 year later, we contacted FFAs to enquire about their application outcome and current respiratory symptoms.

RESULTS

Data were available on 116 applicants; of whom, 45% (n = 52) had definite/probable current asthma and were significantly more likely to be older, atopic to common aeroallergens, report atopic disease and have a lower forced expiratory volume in one second/forced vital capacity ratio compared with applicants with no current asthma. Only two individuals' applications were rejected due to asthma. At follow-up, just 2 (2%) of the 90 operational firefighters reported any recent trouble with asthma.

CONCLUSIONS

A history of asthma alone is not sufficient to determine current asthma in FFAs. Even with a diagnosis of current asthma, FFAs are mostly successful in their application to join the fire service.

Decreased Pulmonary Function Over 5 Years in US Firefighters

To examine changes in pulmonary function over a 5-year period in US firefighters.

Assessing decontamination and laundering processes for the removal of polycyclic aromatic hydrocarbons and flame retardants from firefighting uniforms

Firefighter uniforms protect firefighters from exposure to potentially harmful chemicals including a range of semi-volatile organic compounds (SVOCs). Contaminated uniforms can become a secondary source of firefighters' exposure to these chemicals. There is inconsistency on the removal efficiency of SVOCs during the cleaning, laundering and field decontamination of firefighting uniforms. Therefore, this study aims to assess how effective decontamination and laundering processes are in reducing firefighter uniforms as a vector for transport and exposure to SVOCs. Firefighters who had attended a controlled house fire and simulated container burns had their uniforms sampled pre- and post-laundering. Clean station wear was laundered with contaminated uniforms and after a load of contaminated uniforms to assess inter and intra load contamination. Surface wipes were collected from uniforms across 12 fire stations, after they had returned from a laundering provider. Concentrations of 13 polycyclic aromatic hydrocarbons (PAHs), six organophosphate flame retardants (OPFRs) and seven polybrominated diphenyl ethers (PBDEs) were measured in the collected samples. The concentrations of ∑₁₃ PAHs in firefighters uniforms ranged between 0.063 and 43 μg g^-1, while concentration of ∑₆ OPFRs were between 0.061 and 90 μg g^-1 with ∑₇ PBDEs concentrations being measured between 0.00054 and 0.97 μg g^-1.The highest concentrations of ∑₁₃ PAHs were measured on the outer layers of gloves at an average of 19 μg g^-1, with the highest ∑₆ OPFRs concentrations being measured in the middle layers of gloves at an average of 31 μg g^-1. The highest ∑₇ PBDEs concentrations were measured on the shell layers of turnout jackets at 0.42 μg g^-1. The significant reduction in ∑₁₃ PAHs after laundering or decontamination was only found in 3 of the 16 sampled areas from firefighting uniforms. No significant differences were found in the between pre- and post-laundering concentrations of ∑₆ OPFRs or ∑₇ PBDEs in firefighting uniforms. The current laundering techniques do not appear to effectively remove PAHs, OPFRs and PBDEs at the measured concentrations from firefighters' uniforms. Further research is required to assess if chemical exposure though firefighting uniforms poses a health risk to firefighters and to develop methods for the removal of SVOCs from firefighting uniforms.

Characterising the exposure of Australian firefighters to polycyclic aromatic hydrocarbons generated in simulated compartment fires

Firefighters are exposed to a wide variety of chemicals including polycyclic aromatic hydrocarbons (PAHs) while attending fire scenes. The objective of this study was to understand the exposure of firefighters to PAHs when attending simulated compartment fires that consisted of either a diesel pan or particleboard fire. Firefighters remained in the compartment fires for 15 min while using standard gear including self contained breathing apparatus (SCBA). Firefighters were able to remove firefighting clothing and shower within 10 min of leaving the burn. Air samples were collected from inside the compartment during the fire. Twenty-six (26) firefighters participated in the study providing urine and skin wipe samples collected from the wrist and neck before and after either one of the burn types. The concentrations of PAHs were measured in skin wipes and air samples, while concentrations of monohydroxy metabolites of PAHs (OH-PAHs) were measured in urine. The concentrations of all PAHs were significantly higher (p < 0.05) in the smoke layer of particleboard fires than in diesel pan fires. Correspondingly, the level of PAHs deposited on the wrists and necks of participants attending the particleboard fires was higher than those attending diesel pan fires. Urine samples from participants who attended diesel pan fires showed no significant difference (p > 0.05) in the concentration of all OH-PAHs between pre-burn and post-burn. Samples from participants who attended particleboard fires, showed no significant difference (p > 0.05) between 1-hydroxypyrene (1-OH-PYR) concentrations in urine pre- and post-burn. However, median concentrations of hydroxynaphthalenes (OH-NAPs), hydroxyfluorenes (OH-FLUs) and hydroxyphenanthrenes (OH-PHEs) increased significantly from 5.2, 0.44 and 0.88 μg g^-1 creatinine pre-burn to 12, 1.4 and 1.2 μg g^-1 creatinine post-burn, respectively. This suggests that in compartment burns with high concentrations of PAHs in the smoke layer, such as those created by the particleboard fires, exposure to PAHs can be observed though urinary OH-PAH metabolites. Overall, concentrations of urinary OH-PAHs were relatively low considering the potential exposure in these burns. This suggests protective equipment in combination with rapid removal of firefighting ensembles and showering are relatively effective in controlling exposure.

The occurrence of PAHs and flame-retardants in air and dust from Australian fire stations

Firefighters are exposed to a wide range of chemicals whilst on duty, including polycyclic aromatic hydrocarbons (PAHs), organophosphate flame-retardants (OPFRs), and polybrominated diphenyl ethers (PBDEs). These groups of chemicals are related to combustion emissions. PAHs are formed during combustion. OPFRs and PBDEs are flame-retardants and are inadvertently released during combustion. Exposure to these chemicals occurs when attending fire scenes, and firefighters can track these chemicals back into fire stations leading to further exposure. The objective of this study was to understand the concentrations of PAHs, OPFRs, and PBDEs in fire stations, to evaluate factors that affect chemical concentration, and to assess how air and dust could contribute to firefighters' relevant exposure risk. Concentrations of 13 PAHs, 9 OPFRs, and 8 PBDEs were quantified in fire station dust (n = 49) and air (n = 15) samples collected between November 2017 and February 2018. The median ∑₁₃PAH concentration was 15 ng m^-3 and 3.1 µg g^-1 in air and dust, respectively, while the median ∑₉ OPFR concentration was 56 ng m^-3 in air and 84 µg g^-1 in dust, and ∑₈ PBDE had a median concentration of 0.78 ng m^-3 in air and 26 µg g^-1 in dust. The estimated daily intakes through dust and air for ∑₁₃ PAHs, ∑₉ OPFRs, and ∑₈ PBDEs in firefighters were 3.6, 17, and 1.6 ng (kg body weight)^-1day^-1, respectively. The worst-case estimated daily intakes were only 2% of the reference dose for individual chemicals. Pearson's correlations with chemical concentration for several PAHs, OPFRs, and PBDEs were found between the number of years since fire stations were last renovated, as well as the storage locations of firefighting ensembles. These results suggest chemicals are brought back to fire stations from fire scenes and that they are accumulating in fire stations. They also suggest soiled firefighting ensembles are a source of these chemicals in fire stations and that their proximity to the rest of the station determines the extent to which they contribute to chemical concentrations in fire stations.

Women Firefighters' Health and Well-Being: An International Survey

OBJECTIVES

This study aimed to identify specific health and well-being issues that women firefighters may experience as part of their daily working practices. Issues identified from this under-represented population can drive future research, education, and strategy to guide safety and health practices.

METHODS

A total of 840 women firefighters from 14 separate countries (255 United Kingdom and Ireland, 320 North America, 177 Australasia, and 88 mainland Europe) completed the survey over a 4-month period. Questions related to general health and well-being and role-specific health concerns, gender-related issues, and available exercise facilities.

RESULTS

Women firefighters in North America reported a higher prevalence of lower back (49%) and lower limb (51%) injuries than all other groups. North American respondents reported more heat illnesses (45%) than respondents from other places (36%). Although many participants did not respond, of those who did, 39% thought the menstrual cycle (199/512) or menopause (55/151) affected their work, and 36% were concerned for their ability to meet future job demands. Sixteen percent felt confident they could complete the role after 60 years of age. Women firefighters identified a lack of strength and conditioning support (50%) or lack of gym access (21%). There appears to be poor availability of female-specific personal protective equipment, with availability greatest in the United Kingdom (66%) compared with the sample as a whole (42%).

CONCLUSIONS

There is a need for female-specific strength and conditioning support and facilities to decrease injury and illness risk and improve longevity. Research and education into gynecological issues, heat exposure, and their effects on women firefighters' fertility and cancer risk is required.

Risk of asthma and chronic obstructive pulmonary disease in a large historical cohort of Danish firefighters

OBJECTIVE

Firefighters are exposed to numerous respiratory hazards, but large studies on the risk of pulmonary disease are scarce. The objective of this study was to examine incidence of asthma and chronic obstructive pulmonary disease (COPD) in a nationwide cohort of Danish firefighters.

METHODS

We used individual historical employment records on 11 968 Danish male firefighters primarily supplied by trade unions and fire agencies. Furthermore, we used the Supplementary Pension Fund Register to form an occupational reference group consisting of military employees. Information on respiratory incidence was retrieved from the nationwide Danish National Patient Registry. Age and calendar time standardised incidence ratio (SIR) and Poisson regression analyses (incidence rate ratio) were used for estimation of risks, including 95% CIs.

RESULTS

Compared with military employees, the overall age and calendar-time adjusted risk for asthma was significantly increased among full-time firefighters (SIR=1.58, 95% CI 1.32 to 1.88), but not among part-time/volunteer firefighters. Full-time firefighters' risk for asthma did not vary by duration of employment. No consistent evidence of an increased risk for chronic obstructive pulmonary disease was detected.

CONCLUSION

Danish firefighters have an increased risk of asthma, but the causes, whether occupational or not, remain to be established.

Fire service instructors' working practices: A UK survey

Analysis of Fire Service Instructors (FSI) working practices and health is needed to minimise health risks related to heat illness, cardiovascular events and immunological stress. Online surveys were distributed to UK FSI and Firefighters (FF). One hundred and thirty FSI (age: 43 ± 7yrs) and 232 FF (age: 41 ± 8yrs) responded. FSI experienced 2-10 live fires per week, with 45% of FSI reporting management does not set a limit on the number of exposures. Few FSI followed hydration guidelines, or cooling methods. New symptoms of ill health were reported by 41% of FSI and 21% of FF. FSI with ≥11 Breathing Apparatus exposures per month were 4.5 times (95% CI 1.33-15.09) more likely to experience new symptoms. A large proportion of FSI are experiencing new symptoms of illness after starting their career, and guidelines on exposure and hydration are not universally in place to reduce the risk of future health problems.

A cross-sectional survey of occupational history as a wildland firefighter and health

BACKGROUND

Little is known regarding the impact of long-term wildland firefighting on health. Our objective was to investigate associations between duration of wildland firefighting experience and the prevalence of self-reported health outcomes.

METHODS

We ascertained employment, health, and demographic information on 499 current wildland firefighters (WLFFs) via questionnaire.

RESULTS

Relative to those with less than 10 years of experience as a WLFF, those with 10-19 years of experience had significantly greater odds of having ever been diagnosed with hypertension, as did those with 20 or more years of experience. Significant associations were observed for report of physician-diagnosed heart arrhythmia and previous knee surgery.

CONCLUSIONS

We observed significant links between a greater number of years as a WLFF and self-report of two subclinical cardiovascular risk factors as well as markers of musculoskeletal health. Additional studies are needed to determine if findings can be generalized to all WLFFs.

Occupational and environmental risk factors for chronic rhinosinusitis: a systematic review

BACKGROUND

Chronic rhinosinusitis (CRS) is a prevalent and disabling paranasal sinus disease, with a likely multifactorial etiology potentially including hazardous occupational and environmental exposures. We completed a systematic review of the occupational and environmental literature to evaluate the quality of evidence of the role that hazardous exposures might play in CRS.

METHODS

We searched PubMed for studies of CRS and following exposure categories: occupation, employment, work, industry, air pollution, agriculture, farming, environment, chemicals, roadways, disaster, and traffic. We abstracted information from the final set of articles across 6 primary domains: study design; population; exposures evaluated; exposure assessment; CRS definition; and results.

RESULTS

We identified 41 articles from 1080 manuscripts: 37 occupational risk papers, 1 environmental risk paper, and 3 papers studying both categories of exposures. None of the 41 studies used a CRS definition consistent with current diagnostic guidelines. Exposure assessment was generally dependent on self-report or binary measurements of exposure based on industry of employment. Only grain, dairy, and swine operations among farmers were evaluated by more than 1 study using a common approach to defining CRS, but employment in these settings was not consistently associated with CRS. The multiple other exposures did not meet quality standards for reporting associations or were not evaluated by more than 1 study.

CONCLUSION

The current state of the literature allows us to make very few conclusions about the role of hazardous occupational or environmental exposures in CRS, leaving a critical knowledge gap regarding potentially modifiable risk factors for disease onset and progression.

Mortality due to malignant and non-malignant diseases in Korean professional emergency responders

OBJECTIVE

This study was conducted to estimate the cause-specific mortality in male emergency responders (ER), compare with that of Korean men. Mortality was also compared between more experienced firefighters (i.e., firefighters employed ≥ 20 years and firefighters employed ≥ 10 to < 20 years) and less experienced firefighters and non-firefighters (i.e., firefighters employed < 10 years and non-firefighters) to investigate associations between mortality and exposure to occupational hazards.

METHODS

The cohort was comprised of 33,442 males who were employed as ERs between 1980 and 2007 and not deceased as of 1991. Work history was merged with the death registry from the National Statistical Office of Korea to follow-up on mortality between 1992 and 2007. Standardized mortality ratios (SMR) for ERs were calculated in reference to the Korean male population. Adjusted relative risks (ARRs) of mortalities for firefighters employed ≥ 20 years and ≥ 10 years to < 20 years were calculated in reference to non-firefighters and firefighters employed < 10 years.

RESULTS

Overall (SMR = 0.43, 95%CI = 0.39-0.47) and some kinds of cause-specific mortalities were significantly lower among ERs compared with the Korean male population. No significant increase in mortality was observed across the major ICD-10 classifications among ERs. Mortality due to exposure to smoke, fire, and flames (SMR = 3.11, 95% CI = 1.87-4.85), however, was significantly increased among ERs. All-cause mortality (ARR = 1.46, 95% CI=1.13-1.89), overall cancer mortality (ARR = 1.54, 95% CI = 1.02-2.31) and mortality of external injury, poisoning and external causes (ARR = 3.13, 95% CI = 1.80-5.46) were significantly increased among firefighters employed ≥ 20 years compared to those of non-firefighters and firefighters employed < 10 years.

CONCLUSIONS

An increase in mortality due to all cancer and external injury, poisoning, and external causes in firefighters employed ≥ 20 years compared with non-firefighters and firefighters employed < 10 years suggests occupational exposure.

Exposure-response relationships for select cancer and non-cancer health outcomes in a cohort of U.S. firefighters from San Francisco, Chicago and Philadelphia (1950-2009)

OBJECTIVES

To examine exposure-response relationships between surrogates of firefighting exposure and select outcomes among previously studied US career firefighters.

METHODS

Eight cancer and four non-cancer outcomes were examined using conditional logistic regression. Incidence density sampling was used to match each case to 200 controls on attained age. Days accrued in firefighting assignments (exposed-days), run totals (fire-runs) and run times (fire-hours) were used as exposure surrogates. HRs comparing 75th and 25th centiles of lagged cumulative exposures were calculated using loglinear, linear, log-quadratic, power and restricted cubic spline general relative risk models. Piecewise constant models were used to examine risk differences by time since exposure, age at exposure and calendar period.

RESULTS

Among 19,309 male firefighters eligible for the study, there were 1333 cancer deaths and 2609 cancer incidence cases. Significant positive associations between fire-hours and lung cancer mortality and incidence were evident. A similar relation between leukaemia mortality and fire-runs was also found. The lung cancer associations were nearly linear in cumulative exposure, while the association with leukaemia mortality was attenuated at higher exposure levels and greater for recent exposures. Significant negative associations were evident for the exposure surrogates and colorectal and prostate cancers, suggesting a healthy worker survivor effect possibly enhanced by medical screening.

CONCLUSIONS

Lung cancer and leukaemia mortality risks were modestly increasing with firefighter exposures. These findings add to evidence of a causal association between firefighting and cancer. Nevertheless, small effects merit cautious interpretation. We plan to continue to follow the occurrence of disease and injury in this cohort.

Chronic respiratory conditions in a cohort of metropolitan fire-fighters: associations with occupational exposure and quality of life

OBJECTIVES

To assess the prevalence of chronic respiratory conditions in metropolitan fire-fighters and to study associations between occupational exposure, use of respiratory protection and health-related quality of life (HRQoL) in fire-fighters with and without chronic respiratory conditions.

METHODS

Cross-sectional cohort analysis: Respiratory symptoms, medical conditions, occupational tasks and exposures and consistency of using respiratory protection were inquired by questionnaire. The SF12(®)V2 Health Survey was used to measure physical (PCS-12) and mental (MCS-12) HRQoL. Fire-fighters were categorised in subgroups: asthma; COPD/emphysema/chronic bronchitis; no chronic respiratory conditions; and as being 'not involved' or 'involved' in fire-fighting tasks, the latter further categorised as 'consistent' or 'inconsistent' use of respiratory protection. PCS-12 and MCS-12 scores were compared between subgroups and categories using linear regression.

RESULTS

Five hundred and seventy fire-fighters were analysed, 24 (4%) fulfilled the criteria for asthma, 39 (7%) for COPD/emphysema/chronic bronchitis. Fire-fighters with asthma were older than those in the other two subgroups and had been employed in the fire service longer. Respiratory subgroups did not differ in their involvement in fire-fighting tasks. Ninety-one percent of fire-fighters reported relevant occupational exposure in the past year. Mean PCS-12 scores for fire-fighters with no chronic respiratory conditions, asthma and COPD/emphysema/bronchitis were 52.0 (SD 6.9), 47.0 (8.5) and 48.1 (9.4). For PCS-12 (but not for MCS-12), interaction between having a chronic respiratory condition and inconsistent use of respiratory protection during fire knockdown was observed (p < 0.001).

CONCLUSIONS

Ten percent of metropolitan fire-fighters reported underlying chronic respiratory conditions. Presence of such a condition in combination with suboptimal protection from inhaled exposures may lead to poorer physical HRQoL.

Non-cancer occupational health risks in firefighters

BACKGROUND

Firefighters are exposed to a number of different workplace hazards. As a result of this and the perception of increased ill-health symptoms, a systematic review was carried out to identify significant associations.

AIMS

To carry out a systematic review of evidence relating to non-cancer occupational health risks in firefighters.

METHODS

Systematic literature searches were conducted using a predetermined search strategy that encompassed terms describing the population of interest and health outcomes. Titles and abstracts identified were subjected to an initial screening process using specified guidelines. Included papers were reviewed and data extracted. Additional material, in the form of papers cited by those selected for review, was also obtained and, where relevant, added to the review. Extracted data were then collated into evidence tables to support the narrative review.

RESULTS

Relatively few papers were identified that addressed forms of ill-health in firefighters other than cancer. Nine papers were considered covering each of coronary heart disease and respiratory health. Other ill-health outcomes studied were hearing loss (five studies); hip osteoarthritis (two studies); and sarcoidosis (two studies). None of these sets of papers provided conclusive evidence of a consistent relationship between the specified disease outcomes and the occupation as a firefighter; although, in some instances (hearing loss, respiratory health, and hip and knee osteoarthritis), there were limited indications of some effect.

CONCLUSIONS

None of the sets of papers reviewed showed any consistent association between the occupation of firefighter and any of a number of non-cancer disease and ill-health outcomes.

Personal carbon monoxide exposures among firefighters at prescribed forest burns in the Southeastern United States

Exposure to combustion products from wildland fires causes respiratory irritation and decreased lung function among firefighters. The authors evaluated carbon monoxide (CO) exposures of a group of wildland firefighters who conducted prescribed burns in the southeastern United States of America. A total of 149 person-days of samples were collected using data logging CO monitors. A questionnaire was administered to collect data on job tasks and self-reported smoke exposure. Overall, the highest exposures were seen amongst firefighters assigned to holding and mop-up tasks (geometric mean [GM]: 2.6 ppm), whereas the lowest were associated with lighting and jobs such as burn boss (GM: 1.6 and 0.3 ppm, respectively). The self-reported smoke exposure showed a significant linear trend with increasing CO exposure. The numbers of acres burned or burn duration, however, were not good predictors of exposure.

Resting and post bronchial challenge testing carbon dioxide partial pressure in individuals with and without asthma

Objective

There is conflicting evidence about resting carbon dioxide levels in asthmatic individuals. We wanted to determine if transcutaneously measured carbon dioxide levels prior and during bronchial provocation testing differ according to asthma status reflecting dysfunctional breathing.

Methods

We investigated active firefighters and policemen by means of a validated questionnaire on respiratory symptoms, spirometry, bronchial challenge testing with methacholine (MCT) and measurement of transcutaneous blood carbon dioxide partial pressure (PtcCO₂) at rest prior performing spirometry, one minute and five minutes after termination of MCT. A respiratory physician blinded to the PtcCO₂ results assigned a diagnosis of asthma after reviewing the available study data and the files of the workers medical screening program.

Results

The study sample consisted of 128 male and 10 female individuals. Fifteen individuals (11%) had physician-diagnosed asthma. There was no clinically important difference in median PtcCO₂ at rest, one and five minutes after recovery from MCT in asthmatics compared to non-asthmatics (35.6 vs 35.7 mmHg, p = 0.466; 34.7 vs 33.4 mmHg, p = 0.245 and 37.4 vs 36.4 mmHg, p = 0.732). The median drop in PtcCO₂ during MCT and the increase after MCT was lower in asthmatics compared to non-asthmatics (0.1 vs 3.2 mmHg, p = 0.014 and 1.9 vs 2.9 mmHg, p = 0.025).

Conclusions

PtcCO₂ levels at rest prior and during recovery after MCT do not differ in individuals with or without physician diagnosed asthma. The fall and subsequent increase in PtcCO₂ levels are higher in non-asthmatics than in asthmatics and seems to be related with increased number of respiratory maneuvers during MCT.

Acute respiratory effects in firefighters

BACKGROUND

Associations between acute respiratory inflammatory responses, changes in bronchial hyperresponsiveness, serum pneumoprotein levels, and exposure to fire smoke were studied.

METHODS

The study comprised 51 firefighters. Blood samples were taken within 24 hr following exposure to fire smoke, and after a week and 3 months. Sputum was induced within 5 days post-exposure and subjects underwent spirometry and methacholine provocation one week post-exposure. Exposure was registered by a questionnaire.

RESULTS

No changes were observed following smoke exposure in bronchial hyperresponsiveness and serum pneumoprotein levels. Nevertheless, in a sizable proportion of the firefighters (44%) elevated sputum neutrophil levels (≥60%) were found. Serum IL-8 concentrations were higher 24 hr post-exposure compared to pre-exposure. Elevated neutrophil levels in sputum were associated with elevated serum IL-8 (β = 0.010, P = 0.004) and TNFα (β = 0.005, P = 0.034) levels within 24 hr post-exposure and IL-8 elevation lasted up to 3 months.

CONCLUSIONS

Acute exposure to fire smoke induces acute neutrophilic airway and long-lasting systemic inflammation in healthy firefighters in the absence of bronchial hyperresponsiveness.

Short-term spirometric changes in wildland firefighters

BACKGROUND

The short-term effects of smoke inhalation have been little studied in European wildland firefighters, especially in an intra-individual design. Our purpose is to study the spirometric changes from the early stage during a wildland fire season and to compare smokers and non-smokers.

METHODS

A population of 108 firefighters from a Civil Security Unit, based in Corsica, was tested immediately after having been exposed to the smoke of coniferous trees.

RESULTS

Out of 108 people, 59 were smokers and 49 were non-smokers without any acute or chronic pulmonary disease. Compared to baseline values, a decrease of spirometric parameters was observed immediately after the end of exposure and an even greater decrease was seen after 24 hr (FEV1 -0.53 L; FVC -0.59 L; PEF -53 L min(-1), P < 0.05 for each). None of the participants complained of respiratory symptoms. Three months after the end of the season, a final test was given which revealed a persistent decrease in spirometric parameters in comparison with baseline values (FEV1 -0.28 L; FVC -0.34 L; PEF -45 L min(-1), P < 0.05 for each). Comparison of smoking and non-smoking groups did not show any noteworthy difference for each parameter or the importance of their decline.

CONCLUSIONS

The findings show that firefighters are likely to develop respiratory impairments after wood smoke exposure. We did not observe any statistical differences between smokers and non-smokers.

Tobacco use among firefighters in the central United States

BACKGROUND

This study provides a comprehensive, population-based examination of tobacco use among both career and volunteer firefighters.

METHODS

Data are from a population-based cohort study of randomly selected career (N = 11) and volunteer (N = 13) departments comprised of 677 male firefighters.

RESULTS

Unadjusted rates of smoking were 13.6% and 17.4% for career and volunteer firefighters, respectively. Smoking rates were less than a comparable occupational group (military personnel) and adult males in the states represented. Smokers were more likely to have been diagnosed with an anxiety disorder (OR = 5.8; P = 0.010), have an elevated CAGE alcohol problem score (OR = 2.9; P = 0.040), and more likely to report driving after drinking too much (OR = 4.5; P = 0.020) compared to never-smokers. Large percentages of career (18.4%) and volunteer (16.8%) firefighters used smokeless tobacco. CONCLUSIONS Smoking among firefighters is associated with other significant health and safety risks. High rates of smokeless tobacco use suggest that the fire service is an important target for intervention. Thus, despite strong statements against smoking by the fire service, the need to maintain high levels of health and fitness and relatively low smoking rates, a significant proportion of firefighters continue to use tobacco products.

Novel monitor paradigm for real-time exposure assessment

A wearable monitor that can reliably, accurately, and continuously measure personal exposure levels of various toxicants would not only accelerate the current environmental and occupational health and safety studies, but also enable new studies that are not possible with the current monitoring technology. Developing such a monitor has been a difficult challenge, and requires innovative sensing science and creative engineering. We have developed, built, and tested a wearable monitor for real-time detection of toxic hydrocarbons and acids in the environment. The monitor is low-cost, accurate, and user friendly. In addition, it can communicate wirelessly with a cell phone in which the monitoring results can be processed, displayed, stored, and transmitted to a designated computer. We have validated the functions and performance of the monitor, and carried out field tests with workers involving waste management, fire overhaul, and floor-cleaning activities, as well as with first- and second-hand smokers. The averaged exposure levels are in agreement with those determined by the standard NIOSH methods. The monitor provides accurate and real-time exposure assessment for the workers involving different activities. The real-time and continuous monitoring capability makes it possible to correlate the exposure levels with different activities and changes in the microenvironments. The monitor provides unprecedented real-time information that will help advance occupational safety and environmental health studies. It may also be used to better protect workers from occupational overexposure to toxic molecules.

Respiratory symptoms in firefighters

BACKGROUND

The aim of the present study was to determine the prevalence and risk factors associated with respiratory symptoms in common firefighters in the Netherlands.

METHODS

A total of 1,330 firefighters from the municipal fire brigades of three provinces of the Netherlands were included in the study. All subjects were administered a Dutch web-based version of the European Community Respiratory Health Survey questionnaire.

RESULTS

General respiratory symptoms were associated with the number of fires fought in the last 12 months with odds ratios between 1.2 (95% CI 1.0-1.4) and 1.4 (95% CI 1.2-1.7) per 25 fires. A strong association was found between an inhalation incident and present respiratory symptoms with odds ratios between 1.7 (95% CI 1.1-2.7) and 3.0 (95% CI 1.9-4.7). Adjustments for smoking, sex, atopy, and age did not change any of the associations. After stratification, atopics showed elevated odds ratios.

CONCLUSIONS

It is recommended that firefighters are aware of these elevated healthcare risks associated with exposure to fire smoke and that they increase as much as possible the use of self-contained breathing apparatus.

Monitoring of firefighters exposure to smoke during fire experiments in Portugal

Forest fires represent a serious threat to public security in Europe due to the large burned area. Moreover, smoke pollution due to forest fire events is an important public health issue for the communities directly affected, and particularly for the personnel involved in firefighting operations. Aiming to contribute to the scientific knowledge concerning firefighters exposure to forest fires smoke, data of individual exposure to carbon monoxide, nitrogen dioxide, volatile organic compounds, and particulate matter were obtained during experimental field fires for a group of 10 firefighters equipped with portable "in continuum" measuring devices. Measured values are very high exceeding the Occupational Exposure Standard limits, in particular for peak limit thresholds. These are the first measurements and analysis of firefighter's individual exposure to toxic gases and particles in fire smoke experiments in Europe. However, they already indicate that urgent measures to avoid these levels of exposure are needed.

Spirometry and impulse oscillometry (IOS) for detection of respiratory abnormalities in metropolitan firefighters

BACKGROUND AND OBJECTIVE

As firefighters are at increased risk of adverse health effects, periodic examination of their respiratory health is important. The objective of this study was to establish whether the use of impulse oscillometry (IOS) reveals respiratory abnormalities in metropolitan firefighters that go undetected during routine respiratory health screening by spirometry and assessment of respiratory symptoms.

METHODS

This was a cross-sectional analysis of spirometry, IOS and questionnaire data from 488 male firefighters. Abnormal spirometry was defined as FEV(1), FEV(1)/FVC and/or FEF(50) below the lower limit of normal. Abnormal IOS was defined as resistance at 5 Hz (R5), frequency dependence of resistance (DeltaR5-R20) and/or reactance area (AX) above the upper limit of normal. Respiratory symptoms, smoking history, exposures and medical history were assessed. Data were analysed using logistic and linear regression models.

RESULTS

The mean age of the firefighters was 43.8 (SD 8.4) years. There were 123 (25%) former smokers and 50 (10%) current smokers. Abnormal spirometry was detected in 12%, abnormal IOS in 9% and respiratory symptoms in 20% of firefighters. Current smoking was associated with all IOS parameters (OR for R5 = 3.1, OR for DeltaR5-R20 = 7.7, OR for AX = 4.3), and with FEF(50) (OR = 9.1), chronic productive cough (OR = 4.0) and breathlessness (OR = 5.4) (P < 0.05 for all). Exposure during firefighting duties was associated with chronic productive cough (OR = 2.6), but not with spirometry or IOS parameters. Interaction terms in the linear regression models indicated associations between smoking and DeltaR5-R20, and also between smoking and AX, in the lowest and second lowest quartiles of spirometry parameters.

CONCLUSIONS

Application of IOS for the assessment of respiratory health in firefighters identified airways dysfunction in some individuals, even when spirometry values were within the normal range and there were no respiratory symptoms.

Prevalence and risk of asthma symptoms among firefighters in São Paulo, Brazil: a population-based study

The firefighters are at increased risk of respiratory disease as a result of exposure to smoke and dust. The aim of this study was to determine the prevalence and risk associated with respiratory symptoms among city firefighters in São Paulo, Brazil.

METHODS

A cross-sectional study utilizing the European Community Respiratory Health Survey (ECRHS) questionnaire was administered to firefighters and police officers, in order to evaluate their respiratory symptoms.

RESULTS

Complete respiratory data were obtained from 1,235 firefighters and 1,839 police officers. Among the firefighters, there were 55.5% never-smokers, 22.4% current smokers and 18.2% former smokers (P < 0.05). Among the police officers, there were 63.4%, 18.6%, and 9.6% who were never-smokers, current smokers and former smokers (P < 0.05), respectively. Compared to police, firefighters experienced an increase in wheezing [OR = 1.63 (95% CI: 1.43-1.87)], wheezing with breathlessness [OR = 1.34 (95% CI: 1.10-1.64)], wheezing without a cold [OR = 1.60 (95% CI: 1.32-1.95)], waking with tightness in the chest [OR = 1.20 (95% CI: 1.02-1.42)], and rhinitis [OR = 1.12 (95% CI: 1.03-1.22)]. The prevalence of adult-onset asthma in never-smokers was 9.3% and 6.7% for firefighters and police officers [OR = 1.23 (95% CI: 1.01-1.56)]. An independent association was observed between years employed, smoking, history of rhinitis, and work as a firefighter and respiratory and nasal symptoms. We observed a high prevalence of asthma-like symptoms in firefighters who presented respiratory symptoms beginning immediately after firefighting.

CONCLUSION

These results suggest that the prevalence of respiratory symptoms and asthma in firefighters is higher than those in police officers. Work-as a firefighter, rhinitis and years employed were risk factors for respiratory symptoms of asthma.

Respiratory protection programs for firefighters: a survey of practices for the state of Kentucky

OBJECTIVE

Firefighters play a crucial role as first responders in a variety of situations that can expose them to respiratory hazards. To ensure their safety and health, fire departments should have a respiratory protection program in place for all firefighters. A survey of Kentucky fire departments was conducted to assess their respiratory protection practices, barriers to program implementation, and medical evaluation programs.

METHOD

A 21-question survey assessing respiratory practices during the previous 12 months was mailed to all Kentucky fire departments.

RESULTS

A 62% survey response rate was achieved, with 116 of Kentucky's 120 counties returning at least one survey. All respondents indicated they were utilizing some type of respiratory protection, but only 37% indicated they had a written respiratory protection program. Compensation status and department sizes were found to be significant variables (p < 0.01) in determining if a fire department had a written respiratory protection program. Lack of funding (48%) and lack of understanding (39%) were cited as the greatest barriers to program implementation. Only 51% indicated they require their firefighters to receive a fit testing of their respirator, and 23% indicated they had a health-care provider who reviewed medical questionnaires or provided medical evaluations.

CONCLUSION

This survey indicates that many Kentucky fire departments are not meeting the legal and voluntary respiratory protection standards and guidelines, and demonstrates the need for improved education and funding to ensure that firefighters are adequately protected from respiratory hazards. This is particularly applicable to small rural volunteer departments, which had the greatest gap in compliance.

Plasma Catecholamine Levels and Neurobehavioral Problems in Indian Firefighters

Firefighting is a stressful and hazardous job. Persons engaged in firefighting are highly exposed to work-related stress as well as to smoke containing a host of chemicals potentially harmful to human health. In order to elucidate whether firefighting affects neuroendocrine and behavioral responses of firefighters, plasma catecholamine (CA) levels and the prevalence of neurobehavioral symptoms in 62 firefighters (all males, mean age 43 yr) and 52 control subjects matched for age and sex were examined in this study. Self-reported neurobehavioral symptoms data were obtained from a questionnaire survey and personal interview. Concentrations of epinephrine (E), norepinephrine (NE) and dopamine (DA) in plasma were measured by high-performance liquid chromatography with electrochemical detection. Compared with matched controls, the firefighters showed higher prevalence (p<0.05) of neurobehavioral symptoms such as burning sensation in the extremities, tingling and numbness, transient loss of memory, and depression, but no significant difference was recorded in the prevalences of anxiety, vertigo and dizziness. The firefighters demonstrated a more than two-fold (p<0.05) rise in plasma levels of E and NE, but the plasma DA level was relatively unchanged. Controlling age and smoking as possible confounders, firefighting was found to be associated with raised E (OR=2.15; 95% CI, 0.98-4.52), and NE levels (OR=2.24 95% CI, 1.22-3.61). In conclusion, the job of firefighting appears to be associated with stimulation of sympathetic activity and a rise in the prevalence of neurobehavioral symptoms.

Municipal firefighter exposure groups, time spent at fires and use of self-contained-breathing-apparatus

BACKGROUND

Previous studies have found significant associations between firefighting and cancer.

METHODS

Fires, vehicle movement, and firefighter job assignment were determined, and storage and distribution of self-contained-breathing-apparatus (SCBAs) were tracked for 12 months. Time spent at fires and use of SCBAs were calculated.

RESULTS

Only 66% of fire department personnel were 1st-line combat firefighters. Number of runs was an unreliable surrogate for time spent at fires. Eight firefighter exposure groups were identified (based on job title, firehall assignment, and time spent at fires), ranging from no exposures to 3,244 min/year/firefighter. SCBAs appear to have been used for approximately 50% of the time at structural fires but for only 6% of the time at all fires.

CONCLUSIONS

Failure of previous studies to identify homogeneous exposure groups may have resulted in misclassification and underestimates of health risks. The approach used in this study may be used in epidemiological studies to identify exposure/response relationships.