Evaluating workplace protection factors (WPFs) of different firefighter PPE interface control measures for select volatile organic compounds (VOCs).

Structural firefighters are exposed to a complex set of contaminants and combustion byproducts, including volatile organic compounds (VOCs). Additionally, recent studies have found structural firefighters' skin may be exposed to multiple chemical compounds via permeation or penetration of chemical byproducts through or around personal protective equipment (PPE). This mannequin-based study evaluated the effectiveness of four different PPE conditions with varying contamination control measures (incorporating PPE interface design features and particulate blocking materials) to protect against ingress of several VOCs in a smoke exposure chamber. We also investigated the effectiveness of long-sleeve base layer clothing to provide additional protection against skin contamination. Outside gear air concentrations were measured from within the smoke exposure chamber at the breathing zone, abdomen, and thigh heights. Personal air concentrations were collected from mannequins under PPE at the same general heights and under the base layer at abdomen and thigh heights. Sampled contaminants included benzene, toluene, styrene, and naphthalene. Results suggest that VOCs can readily penetrate the ensembles. Workplace protection factors (WPFs) were near one for benzene and toluene and increased with increasing molecular weight of the contaminants. WPFs were generally lower under hoods and jackets compared to under pants. For all PPE conditions, the pants appeared to provide the greatest overall protection against ingress of VOCs, but this may be due in part to the lower air concentrations toward the floor (and cuffs of pants) relative to the thigh-height outside gear concentrations used in calculating the WPFs. Providing added interface control measures and adding particulate-blocking materials appeared to provide a protective benefit against less-volatile chemicals, like naphthalene and styrene.

Determination of dynamic air gap thickness and analysis of its relationship with firefighters' joint movement.

Objectives. The purpose of this study was to calculate the dynamic air gap thickness between the human body and the turnout gear. Relationships between the air gap thickness and joint range of motion (ROM) were also explored. Methods. The air gap thickness and joint ROM of 12 male firefighters walking in a control condition with no self-contained breathing apparatus (SCBA) and three varying-strapped SCBAs were measured using three-dimensional (3D) body scanning and 3D inertial motion capture. The interpolation technique was employed to predict the air gap thickness curve during walking. The dynamic air gap thickness was compared with the joint ROM to see how they relate to the location and percentage of movement restriction. Results. During the walking, the air gap fluctuated as a sine curve. Carrying SCBA reduced the air gap thickness at the trunk most (F = 11.17, p < 0.001, η2 = 0.63), and adjusting the shoulder strap length altered the air gap distribution at the trunk. The reduced air gap at the pelvis caused an incremental restriction on pelvis rotation. Conclusions. A compatibility design of the shoulder strap and hip belt in SCBA with the turnout jacket is suggested.

Exploring the adverse effect of fine particulate matter (PM2.5) on wildland firefighters' pulmonary function and DNA damage.

Chiang Mai encounters severe pollution during the wildfire season. Wildland firefighters encounter various hazards while engaged in fire suppression operations, which encompass significant exposure to elevated concentrations of air pollutants resulting from combustion, especially particulate matter. The adverse effects of wildfire smoke on respiratory health are a significant concern. The objective of this study was to examine the potential adverse effects of PM2.5 exposure on the respiratory function and DNA damage of wildland firefighters. This prospective cohort study conducted in Chiang Mai from January to May 2022 planned to evaluate the health status of wildland firefighters during the pre-peak, peak, and post-peak ambient air pollution seasons. The measurement of PM2.5 was done at every forest fire station, as well as utilizing data from the Pollution Control Department. Participants received general health examinations, spirometry evaluations, and blood tests for DNA damage analysis. Pair t-tests and multiple regression models were used to examine the connection between pulmonary function parameters (FVC, FEV1) and PM2.5 concentration, with a significance level of P < 0.05. Thirty-three peak-season and twenty-one post-peak-season participants were enrolled. Four pre-peak-season wildland firefighters had FVC and FEV1 declines of > 15%. Multiple regression analysis showed a negative association between PM2.5 exposure and FVC% predicted (- 2.81%, 95% CI - 5.27 to - 0.34%, P = 0.027) and a marginally significant negative correlation with FVC (- 114.38 ml, 95% CI - 230.36 to 1.59 ml, P = 0.053). The remaining pulmonary measures showed a statistically insignificant decline. There were no significant changes in DNA damage detected. Wildland firefighters suffered a significant decline in pulmonary function associated with PM2.5 exposure. Spirometry is crucial for monitoring and promptly identifying respiratory issues that occur during wildfire seasons. Further research is recommended to explore DNA damage alterations and their potential association with PM2.5.

Distinct Prostate Cancer Survival Outcomes in Firefighters: A Population-Based Study.

Introduction: Survival outcomes for prostate cancer among specific occupational groups prone to regular medical check-ups vis-à-vis the general population have been understudied. For firefighters, a demographic subject to rigorous medical evaluations, possessing above-average medical expertise, and exposed to specific carcinogens of interest, prostate cancer survival in the US has never been studied. Methods: We conducted a retrospective study, utilizing data from the Florida Cancer Data System spanning 2004 to 2014, coupled with firefighter certification records from the Florida State Fire Marshal's Office. Our study cohort consisted of 1058 prostate cancer cases among firefighters as well as prostate cases for the Florida general population (n = 150,623). We compared cause-specific survival between the two using Cox regression models adjusted for demographics and clinical characteristics, including PSA levels, Gleason scores, and treatment modalities. Results: Firefighters demonstrated a higher five-year cause-specific survival rate (96.1%, 95% CI: 94.7-97.1%) than the general population (94.2%, 95%CI: 94.1-94.3%). Overall, firefighters' diagnoses were established at younger ages (median age 63 vs. 67 in the general population), exhibited a higher proportion of localized stage cancers (84.7% vs. 81.1%), and had a greater utilization of surgery (46.4% vs. 37.6%), a treatment modality with a high success rate but potential side effects. In multivariable analysis, firefighters displayed a survival advantage for localized stage (adjusted hazard ratio [aHR] = 0.53; 95%CI: 0.34-0.82). However, for regional or distant stages, firefighters aged 65 and above exhibited a higher risk of death (aHR = 1.84; 95% CI: 1.18-2.86) than the general population. Conclusion: Firefighters experience enhanced prostate cancer survival, primarily in cases diagnosed at localized stages, likely due to increased PSA testing. Nonetheless, for regional or distant stage, survival among older firefighters' lags behind that of the general population. Further investigations are warranted to unravel factors influencing the development of aggressive disease beyond PSA and Gleason scores in this population, as well as to assess the impact of a higher rate of surgical treatment on firefighters' quality of life.

Urine proteome profile of firefighters with exposure to emergency fire-induced smoke: A pilot study to identify potential carcinogenic effects.

Firefighters are frequently exposed to a variety of chemicals formed from smoke, which pose a risk for numerous diseases, including cancer. Comparative urine proteome profiling could significantly improve our understanding of the early detection of potential cancer biomarkers. In this study, for the first time, we conducted a comparative protein profile analysis of 20 urine samples collected from ten real-life firefighters prior to and following emergency fire-induced smoke. Using a label-free quantitative proteomics platform, we identified and quantified 1325 unique protein groups, of which 45 proteins showed differential expressions in abundance in response to fire-smoke exposure (post) compared to the control (pre). Pathway analysis showed proteins associated with epithelium development (e.g., RHCG, HEG1, ADAMTSL2) and Alzheimer's disease (SORL1) were significantly increased in response to smoke exposure samples. A protein-protein-network study showed a possible link between these differentially abundant proteins and the known cancer gene (TP53). Moreover, a cross-comparison analysis revealed that seven proteins-ALDH1A1, APCS, POMC, COL2A1, RDX, DDAH2, and SDC4 overlapped with the previously published urine cancer proteome datasets, suggesting a potential cancer risk. Our findings demonstrated that the discovery proteomic platform is a promising analytical technique for identifying potential non-invasive biomarkers associated with fire-smoke exposure in firefighters that may be related to cancer.

Patterns of comorbid PTSD, depression, alcohol use disorder, and insomnia symptoms in firefighters: A latent profile analysis.

BACKGROUND: Firefighters are an at-risk population for multiple psychiatric conditions, including posttraumatic stress disorder (PTSD), depression, alcohol use disorders (AUDs), and insomnia. These disorders are likely to co-occur; however, patterns of comorbidity have scarcely been investigated in firefighters. We aimed to identify subgroups of comorbidity of PTSD, depression, AUDs, and insomnia in a nationwide population of firefighters in South Korea. METHODS: A total of 54,054 firefighters responded to an online survey. Latent classes of comorbidity were categorized using latent profile analysis (LPA) based on the symptom scores of PTSD, depression, AUDs, and insomnia. Analysis of variance was performed to compare the characteristics of the identified classes, and multinomial logistic regression was conducted to examine whether anger reactions, resilience, and number of traumatic events predicted class membership. RESULTS: The LPA identified four subgroups: minimal symptoms (n = 42,948, 79.5 %), predominant PTSD (n = 2858, 5.3 %), subthreshold symptoms and comorbidity (n = 7003, 13.0 %), and high symptoms and comorbidity (n = 1245, 2.3 %). Three comorbidity classes were defined based on severity and one class showed predominant PTSD symptoms. Number of traumatic exposures predicted predominant PTSD, while resilience and anger reactions predicted severity of comorbidities. LIMITATIONS: The cross-sectional design and usage of self-reported questionnaires are limitations of this study. CONCLUSIONS: The severity of PTSD, depression, AUDs and insomnia tend to correlate and co-occur in firefighters. Our findings highlight the need to assess comorbid symptoms in firefighters and need to reduce anger reactions and enhance resilience in those with multiple comorbidities.

Assessment of Left Lung Remodeling With Magnetic Resonance Imaging in a Murine Model Following Exposure to Douglas Fir Smoke.

Wildland firefighters (WLFFs) experience lung function decline due to occupational exposure to fire smoke. WLFFs typically do not wear respiratory personal protective equipment, and if they do, it is a simple bandana, which is not effective at filtering smoke. To pinpoint the biological underpinnings of abnormal respiratory function following 3-7 years of WLFF service, we exposed mice to Douglas fir smoke (DFS) over 8 weeks. Following exposure, we assessed changes in lung structure through Magnetic Resonance Imaging (MRI) and histological analysis, which was supported by immunohistochemistry staining. With MRI, we found that the signal decay time, T2*, from ultrashort echo time (UTE) images was significantly shorter in mice exposed to DFS compared to air controls. In addition, the variation in T2* was more heterogeneously distributed throughout the left lung in DFS-exposed mice, compared to air controls. As confirmed by histological analysis, shorter T2* was caused by larger parenchyma airspace sizes and not fibrotic remodeling. Destruction of the alveolar spaces was likely due to inflammation, as measured by an influx of CD68+ macrophages and destruction due to enhanced neutrophil elastase. In addition, measurements of airspace dimensions from histology were more heterogeneously distributed throughout the lung, corroborating the enhanced relative dispersion of T2*. Findings from this study suggest that the decline in lung function observed in WLFFs may be due to emphysema-like changes in the lung, which can be quantified with MRI.

Firefighters' Occupational Exposure in Preparation for Wildfire Season: Addressing Biological Impact.

The characterization of wildland firefighters' occupational exposure must consider different exposures, including those at the fire station. The present study aimed to characterize the occupational exposure of 172 Northern Portuguese wildland firefighters in fire stations during the pre-wildfire season of 2021. The biological impact of estimated inhaled doses of PM10 and PM2.5 (indoor/outdoor) was accessed through a buccal micronucleus cytome (BMCyt) assay in exfoliated buccal cells of a subgroup of 80 firefighters. No significant association was found between estimated inhaled doses of PM10 and PM2.5 (mean 1.73 ± 0.43 µg kg-1 and 0.53 ± 0.21 µg kg-1, respectively) and biological endpoints. However, increased frequencies of cell death parameters were found among subjects of the Permanent Intervention Teams (full-time firefighters). The intake of nutritional supplements was associated with a significant decrease in micronucleus frequencies (i.e., DNA damage or chromosome breakage). In addition, our findings showed a significantly increased frequency of cell death endpoints (i.e., nuclear fragmentation) with coffee consumption, while daily consumption of vegetables significantly decreased it (i.e., nuclear shrinkage). Our results provide data on the occupational exposure of wildland firefighters while working in fire stations during the pre-wildfire season, providing the essential baseline for further studies throughout the wildfire season.

The Effect of Emotional Labor on Psychological Well-Being in the Context of South Korean Firefighters: The Moderating Role of Transformational Leadership.

Drawing on insights from the conservation of resources theory and the job demands-resources theory, our study investigates the association between two types of emotional labor-surface and deep acting-and the psychological well-being of firefighters. In addition, it investigates the moderating effect of transformational leadership within this context. To this end, this study utilizes ordinary least squares models to analyze survey data from 1453 firefighters in Gyeonggi-do, South Korea's largest province by population. The findings reveal a negative association between both types of emotional labor and the psychological well-being of firefighters. The study further demonstrates that transformational leadership mitigates the adverse effects of surface acting on psychological well-being. Our research indicates that transformational leadership plays a pivotal role in replenishing lost emotional resources, thereby enhancing the mental and emotional health of those engaged in demanding roles such as firefighting and emergency medical services. Accordingly, the study highlights a vital strategy for maintaining the psychological well-being of firefighters.

Prevalence and predictors of colon and prostate cancer screening among volunteer firefighters: The United States Firefighter Cancer Assessment and Prevention Study.

BACKGROUND: Although firefighters have increased risk for colon and prostate cancer, limited information exists on screening practices for these cancers in volunteer firefighters who compose two-thirds of the US fire service. We estimated the prevalence of colon and prostate cancer screening among volunteer firefighters using eligibility criteria from 4 evidence-based screening recommendations and evaluated factors influencing screening. METHODS: We evaluated colon (n = 569) and prostate (n = 498) cancer screening prevalence in a sample of US volunteer firefighters using eligibility criteria from the US Preventive Services Taskforce (USPSTF), National Fire Protection Association, American Cancer Society, and National Comprehensive Cancer Network. We assessed associations with fire service experience, demographics, and cancer risk perception based on USPSTF guidelines. RESULTS: For those eligible based on USPSTF guidelines, colon and prostate cancer screening prevalence was 51.7% (95% CI: 45.7, 57.8) and 48.8% (95% CI: 40.0, 57.6), respectively. Higher odds of colon and prostate cancer screening were observed with older age and with some college education compared to those with less education. Fire service experience and cancer risk perception were not associated with screening practices. CONCLUSION: This is the first large study to assess colon and prostate cancer screening among US volunteer firefighters based on different screening guidelines. Our findings suggest gaps in cancer prevention efforts in the US volunteer fire service. Promoting cancer screening education and opportunities for volunteer firefighters by their fire departments, healthcare professionals, and public health practitioners, may help to address the gaps.

Baseline data and associations between urinary biomarkers of polycyclic aromatic hydrocarbons, blood pressure, hemogram, and lifestyle among wildland firefighters.

Introduction: Available literature has found an association between firefighting and pathologic pathways leading to cardiorespiratory diseases, which have been linked with exposure to polycyclic aromatic hydrocarbons (PAHs). PAHs are highlighted as priority pollutants by the European Human Biomonitoring Initiative in occupational and non-occupational contexts. Methods: This cross-sectional study is the first to simultaneously characterize six creatinine-adjusted PAHs metabolites (OHPAHs) in urine, blood pressure, cardiac frequency, and hemogram parameters among wildland firefighters without occupational exposure to fire emissions (> 7 days), while exploring several variables retrieved via questionnaires. Results: Overall, baseline levels for total OHPAHs levels were 2 to 23-times superior to the general population, whereas individual metabolites remained below the general population median range (except for 1-hydroxynaphthalene+1-hydroxyacenaphtene). Exposure to gaseous pollutants and/or particulate matter during work-shift was associated with a 3.5-fold increase in total OHPAHs levels. Firefighters who smoke presented 3-times higher total concentration of OHPAHs than non-smokers (p < 0.001); non-smoker females presented 2-fold lower total OHPAHs (p = 0.049) than males. 1-hydroxypyrene was below the recommended occupational biological exposure value (2.5 µg/L), and the metabolite of carcinogenic PAH (benzo(a)pyrene) was not detected. Blood pressure was above 120/80 mmHg in 71% of subjects. Firefighters from the permanent intervention team presented significantly increased systolic pressure than those who performed other functions (p = 0.034). Tobacco consumption was significantly associated with higher basophils (p = 0.01-0.02) and hematocrit (p = 0.03). No association between OHPAHs and blood pressure was found. OHPAHs concentrations were positively correlated with monocyte, basophils, large immune cells, atypical lymphocytes, and mean corpuscular volume, which were stronger among smokers. Nevertheless, inverse associations were observed between fluorene and pyrene metabolites with neutrophils and eosinophils, respectively, in non-smokers. Hemogram was negatively affected by overworking and lower physical activity. Conclusion: This study suggests possible associations between urinary PAHs metabolites and health parameters in firefighters, that should be further assessed in larger groups.

Longitudinal assessment of psychological distress and its determinants in a sample of firefighters based in Montreal, Canada.

Introduction: Firefighters face elevated risks of common mental health issues, with distress rates estimated at around 30%, surpassing those of many other occupational groups. While exposure to potentially traumatic events (PTEs) is a well-recognized risk factor, existing research acknowledges the need for a broader perspective encompassing multidimensional factors within the realm of occupational stress. Furthermore, this body of evidence heavily relies on cross-sectional studies. This study adopts an intensive longitudinal approach to assess psychological distress and its determinants among firefighters. Methods: Participants were recruited from 67 fire stations in Montreal, Canada, meeting specific criteria: full-time employment, smartphone ownership, and recent exposure to at least one PTE, or first responder status. Subjects underwent a telephone interview and were directed to use an app to report depressive, post-traumatic, and generalized anxiety symptoms every 2 weeks, along with work-related stressors, social support, and coping styles. Analyses involved 274 participants, distinguishing between those exceeding clinical thresholds in at least one distress measure (the "distressed" subgroup) and those deemed "resilient." The duration and onset of distress were computed for the distressed group, and linear mixed models were employed to evaluate determinants for each psychological distress variable. Results: Clinical psychological distress was observed in 20.7% of participants, marked by depressive, post-traumatic, and anxiety symptoms, often within the first 4-week reference period. Contextual factors (operational climate, social support, solitude) and individual factors (coping style, solitude and lifetime traumatic events in private life) exhibited more significant impacts on psychological distress than professional pressures within the firefighters' work environment. Discussion: This study reports lower rates of psychological distress than previous research, possibly attributable to sample differences. It highlights that reported symptoms often represent a combined and transient layer of distress rather than diagnosable mental disorders. Additionally, determinants analysis underscores the importance of interpersonal relationships and coping mechanisms for mental health prevention interventions within this worker group. The findings carry implications for the development of prevention and support programs for firefighters and similar emergency workers.

In the heat of the moment: the effects of extreme temperatures on the cognitive functioning of firefighters.

Exposure to high temperatures can have detrimental effects on cognitive processing and this is concerning for firefighters who routinely work in extreme temperatures. Whilst past research has studied the effects of heat on firefighter cognition, findings are mixed, and no work has measured the time course of cognitive recovery. This study compared working memory, vigilance, and cognitive flexibility of 37 firefighters before and after they engaged in a live-fire training exercise with temperatures exceeding 115 °C. To assess recovery, cognition was measured on exiting the fire, then 20- and 40-minutes post-fire. Results showed impaired vigilance and cognitive flexibility (increased errors, slower responses) immediately after the fire, but recovery at 20-minutes. These findings indicate that a live indoor fire negatively impacts cognitive processing, but this effect is relatively short-lived and return to baseline functioning is seen 20-minutes after exiting the fire. The findings could be used to inform re-entry and cooling decisions.

Acute heat stress may affect cognitive processing, posing a health and safety risk to firefighters. This study demonstrates impaired cognition following a firefighter training exercise in temperatures exceeding 115 °C. Cognition recovered as core body temperature returned to normal, providing evidence for a 20-minute cooling period following exposure to extreme heat.

Occupational exposure of firefighters to hazardous pollutants during prescribed fires in Portugal.

Firefighters perform high-risk activities and during the course of their functions are highly exposed to a wide range of occupational hazards, including air pollution. Thus, this study aimed to assess the exposure of firefighters in prescribed wildland fires and their occupational exposure, as well as to identify and chemically characterise the particles collected during wildland firefighting and inside fire stations. Exposure to wildfire smoke was evaluated in 7 prescribed fires in Portugal, 2 in the north and 5 in the south of Viseu district. The concentrations of PM2.5, NO2, SO2, CO and VOCs were monitored and exceedances to occupational exposure limit values were identified. Moreover, the chemical composition of PM2.5 was analysed. The results showed that firefighters were exposed to high concentrations of these pollutants during prescribed fires and that, in some cases, exceeded occupational exposure limits, both for time-weighted average concentrations for an 8-h working day (a time-weighted average, TWA) of PM2.5, and for short-term exposure values (STEL) of NO2 and SO2. Despite being exposed to very high concentrations of CO, no exceedances to the occupational exposure values were observed. FT-IR and SEM-EDS allowed to chemically characterise the composition of the particles collected inside the fire stations and also during wildland fires, identifying mainly quartz, aluminium and magnesium silicates, characteristic of earth's crust constituents. and also, fibres that have undergone combustion. Concluding, firefighters' exposure to high concentrations of harmful pollutants, can lead to the degradation of their respiratory health. It is therefore extremely important to increase existing knowledge and conduct further studies, especially longitudinal ones, that can assess their lung function. This will allow an understanding of the impacts of smoke on firefighters' health and develop effective strategies to protect them during wildland firefighting operations.

Occupational stress and musculoskeletal disorders in firefighters: the mediating effect of depression and job burnout.

The firefighting profession carries a heightened risk of musculoskeletal disorders. A firefighter's job is physically demanding and includes activities such as running, climbing, dragging, and lifting. Often, these tasks are unpredictable, performed in harsh environments, and have been found to cause psychological stress. The purpose of this study was to investigate the effects of occupational stress on work-related musculoskeletal disorders (WRMSD) in firefighters. In addition, the mediating effects of depression and job burnout on proposed relationships were examined. Data informing this study were collected using a survey questionnaire. The survey questionnaire included the Beck Depression Inventory, the Center for Epidemiological Studies Depression Scale (CES-D), the Maslach Burnout Inventory, the Post Traumatic Stress Disorder Inventory (PCL), and the Nordic Musculoskeletal Questionnaire. Collected data were analyzed using structural equation modeling approach in AMOS. The results of the 2339 responding firefighters suggest that work related stress is positively related to WRMSDs in firefighters and can lead to musculoskeletal symptoms through four paths, being emotional exhaustion, personal accomplishment, CES-D total score, and depersonalization. Through depersonalization, job stress had the most significant impact on musculoskeletal symptoms (coefficient = 0.053). Furthermore, the results showed that post-traumatic stress disorders (PTSD) can affect musculoskeletal symptoms through ten paths, again through depersonalization, PTSD had the most significant impact on musculoskeletal symptoms (coefficient = 0.141). The results of this study suggest that organizations should design interventions and policies to prevent and manage occupational stress, depression, and job burnout to negate its undesired consequences on firefighters' health (i.e. WRMSD).

A comparison between the effects of simulation of basic CPR training and workshops on firefighters' knowledge and skills: experimental study.

BACKGROUND: One of the most common causes of death worldwide is cardiopulmonary arrest. Firefighters are among the first responders at the scenes of accidents and can, therefore, play a key part in performing basic cardiopulmonary resuscitation (CPR) for victims who need it. The present study was conducted to compare the effects of simulation training against workshops on the CPR knowledge and skills of firefighters in the south of Iran. METHODS: This experimental (Interventional) study was conducted on 60 firefighters of south of Fars province, Iran. The study was undertaken from March to July 2023. Through random allocation, the participants were divided into two groups: simulation-based training (30 members) and traditional workshop training (30 members). The participants' CPR knowledge and practical skills were measured before, immediately after, and three months after intervention. RESULTS: The findings of the study revealed a statistically significant difference between the pretest and posttest CPR knowledge and skill mean scores of the simulation groups as compared to the workshop group (p < 0.001). As measured three months after the intervention, the firefighters' knowledge and skill mean scores were still significantly different from their pretest mean scores (p < 0.001); however, they had declined, which can be attributed to the fact that the study population did not frequently exercise CPR. CONCLUSION: Based on the findings of the study, even though both methods of education were effective on enhancing the firefighters' CPR knowledge and skill, simulation training had a far greater impact than training in workshops. In view of the decline in the participants' knowledge and skill scores over time, it is recommended that short simulation training courses on CPR should be repeated on a regular basis.

Assessment of PAH exposure and health risks among South Korean firefighters based on urinary PAH metabolites.

Polycyclic aromatic hydrocarbons (PAHs) comprise a group of compounds resulting from the incomplete combustion of organic matter. Firefighters engaged in fire suppression are highly exposed to PAHs. This study centered on evaluating the exposure levels and health risks of PAHs in South Korean firefighters involved in firefighting activities. The concentrations of 10 PAH metabolites in the urine of firefighters were measured immediately after, and two weeks post their engagement in extinguishing a large tire factory fire. The levels of OH-PAHs in urine samples immediately after fire suppression were elevated by a factor of 1.01-1.84 compared to urine samples from non-exposed period. The median concentration of total PAH metabolites (OH-PAHs) was higher in urine samples immediately after fire suppression (5910 ng/g creatinine) than in urine samples from non-exposed periods (5020 ng/g creatinine). However, the ∑OH-PAH levels in firefighters' urine were related to personal habits such as smoking. The concentrations of all individual OH-PAHs in the urine samples of nonsmokers exhibited a substantial increase, ranging from 1.37 to 2.3 times, clearly demonstrating that firefighting activities were a substantial source of PAH exposure. The calculated values associated with the health risks stemming from exposure to PAHs, including carcinogenic risk, total estimated daily intake (TEDI), and hazard quotients/index (HQs/HI), all fell within acceptable limits, indicating negligible risk. However, the HQ/HI values and TEDI for individual and total PAH exposures, except those for naphthalene, were 1.36-2.00 times higher in firefighters' samples taken after firefighting operations compared to those during regular duty. This underscores the need for more comprehensive investigations to comprehend the singular impact of firefighting activities due to the diverse sources of PAH emissions in the environment.

Effects of implementing a mandatory and consequential annual fitness assessment in a fire department over the initial 4-year period.

BACKGROUND: Despite the physical nature of the occupation many firefighters have low levels of physical fitness which is associated with poor performance of occupational tasks and increased injury rates. For many fire departments an initial step in promoting health and wellness within the department is to conduct annual fitness testing. OBJECTIVE: To examine the effects of implementing a consequential fitness assessment within a fire department. METHODS: A retrospective repeated measures design was used to analyze annual fitness assessment data of professional firefighters (n = 1415) from 2019 to 2022 within a large urban fire department located in the mid-Atlantic region of the United States. The fitness tests included assessments of pull-ups, push-ups, sit-ups, aerobic capacity, and body composition. Repeated measure analyses of variances (ANOVAs) assessed the effect of year and a 2-way ANOVA was conducted to investigate the effects of sex and age on fitness measures on 2022 data. RESULTS: All fitness measures were found to be maintained over the 4-year period. Significant main effects of age and sex across all fitness measures, but no significant interactions were found. Older firefighters (50 + years) exhibited lower performance (p <  0.001, d >  0.80) on muscular fitness assessments than young firefighters (20-29 years). A large effect of sex (males >  females) was found for pull-ups (d = 1.04), push-ups (d = 1.23), and aerobic capacity (d = 1.38). CONCLUSIONS: The results suggest that implementing a consequential fitness assessment could help maintain firefighters' fitness levels over a multi-year period.

Normal Lung Function and Mortality in World Trade Center Responders and NHANES III Participants.

RATIONALE: Low forced expiratory volume at one second (FEV1) is a biomarker of increased mortality. The association of normal lung function and mortality is not well described. OBJECTIVE: To evaluate the FEV1-mortality association among participants with normal lung function. METHODS: 10,999 Fire Department of the City of New York (FDNY) responders and 10,901 NHANES III participants, ages 18-65 with FEV1 ≥80% predicted, were analyzed, with FEV1 percent predicted calculated using Global Lung Function Initiative Global race-neutral reference equations. Mortality data were obtained from linkages to the National Death Index. Cox proportional hazards models estimated the association between FEV1 and all-cause mortality, controlling for age, sex, race/ethnicity, smoking history, and, for FDNY, work assignment. Cohorts were followed for a maximum of 20.3 years. MEASUREMENTS AND MAIN RESULTS: We observed 504/10,999 deaths (4.6%) for FDNY and 1,237/10,901 deaths (9.4% [weighted]) for NHANES III. Relative to FEV1 ≥120% predicted, mortality was significantly higher for FEV1 100-109%, 90-99%, and 80-89% predicted in the FDNY cohort. In the NHANES III cohort, mortality was significantly higher for FEV1 90-99% and 80-89% predicted. Each 10% higher predicted FEV1 was associated with 15% (HR=0.85, 95% CI 0.80-0.91) and 23% (HR=0.77, 95% CI 0.71-0.84) lower mortality for FDNY and NHANES III, respectively. CONCLUSIONS: In both cohorts, higher FEV1 is associated with lower mortality, suggesting higher FEV1 is a biomarker of better health. These findings demonstrate that a single cross-sectional measurement of FEV1 is predictive of mortality over two decades, even when FEV1 is in the normal range.

Development and validation of the trauma-specific emotional counting Stroop paradigm for fMRI study.

BACKGROUND: The emotional-counting Stroop (ecStroop) is a cognitive task to evaluate emotional information processing. This study aimed to develop a trauma-specific ecStroop protocol for firefighters and assess its validity as a functional magnetic resonance imaging (fMRI) activation paradigm. METHODS: To develop the ecStroop protocol, trauma-related words for firefighters were selected from previous studies, and general negative and neutral words were matched corresponding to the number of letters and syllables, parts of speech, and frequency in the Korean language. The negative emotional valence of whole words was investigated in 520 healthy participants. To compare brain activation between three categories, 25 healthy individuals underwent fMRI during the ecStroop task. RESULTS: Eight trauma-related words, eight general negative words, and sixteen neutral words were selected by emotional valence scores. The general negative words were related to increased activation in the right inferior and middle temporal gyrus, right medial frontal gyrus, and left superior frontal gyrus compared to the neutral words. When exposed to the trauma-related words, participants' brain activation was increased in the right inferior temporal gyrus, right medial frontal gyrus, left superior temporal gyrus, and left inferior frontal gyrus as compared to when exposed to the neutral words. LIMITATIONS: The fact that all participants in the phase 2 fMRI study were male could limit generalization to all genders. CONCLUSIONS: These findings suggest that the ecStroop paradigm successfully activated the brain regions for emotional processing. This paradigm could be valuable in assessing the trauma-specific neural changes in firefighters.