Dynamic Metabolic Risk Profiling of World Trade Center Lung Disease: A Longitudinal Cohort Study.

Rationale: Metabolic syndrome (MetSyn) increases the risk of World Trade Center (WTC) lung injury (LI). However, the temporal relationship of MetSyn, exposure intensity, and lung dysfunction is not well understood. Objective: To model the association of longitudinal MetSyn characteristics with WTC lung disease to define modifiable risk. Methods: Firefighters, for whom consent was obtained (N = 5,738), were active duty on September 11, 2001 (9/11). WTC-LI (n = 1,475; FEV1% predicted

Cancer incidence in World Trade Center-exposed and non-exposed male firefighters, as compared with the US adult male population: 2001-2016.

OBJECTIVE: To compare cancer incidence in Fire Department of the City of New York (FDNY) firefighters who worked at the World Trade Center (WTC) site to incidence in a population of non-WTC-exposed firefighters, the Career Firefighter Health Study (CFHS) cohort, and to compare rates from each firefighter cohort to rates in demographically similar US males. METHODS: FDNY (N=10 786) and CFHS (N=8813) cohorts included male firefighters who were active on 11 September 2001 (9/11) and were followed until death or 31 December 2016. Cases were identified from 15 state cancer registries. Poisson regression models assessed cancers in each group (FDNY and CFHS) versus US males, and associations between group and cancer rates; these models estimated standardised incidence ratios (SIRs) and adjusted relative rates (RRs), respectively. Secondary analyses assessed surveillance bias and smoking history. RESULTS: We identified 915 cancer cases in 841 FDNY firefighters and 1002 cases in 909 CFHS firefighters. FDNY had: higher rates for all cancers (RR=1.13; 95% CI 1.02 to 1.25), prostate (RR=1.39; 95% CI 1.19 to 1.63) and thyroid cancer (RR=2.53; 95% CI 1.37 to 4.70); younger median ages at diagnosis (55.6 vs 59.4; p<0.001, all cancers); and more cases with localised disease when compared with CFHS. Compared with US males, both firefighter cohorts had elevated SIRs for prostate cancer and melanoma. Control for surveillance bias in FDNY reduced most differences. CONCLUSIONS: Excess cancers occurred in WTC-exposed firefighters relative to each comparison group, which may partially be explained by heightened surveillance. Two decades post-9/11, clearer understanding of WTC-related risk requires extended follow-up and modelling studies (laboratory or animal based) to identify workplace exposures in all firefighters.

SARS-CoV-2 antibody seroprevalence among firefighters in Orange County, California.

OBJECTIVES: We conducted serological SARS-CoV-2 antibody testing from October to November 2020 to estimate the SARS-CoV-2 seroprevalence among firefighters/paramedics in Orange County (OC), California. METHODS: OC firefighters employed at the time of the surveillance activity were invited to participate in a voluntary survey that collected demographic, occupational and previous COVID-19 testing data, and a SARS-CoV-2 immunoglobulin (Ig)G antibody blood test. We collected venous blood samples using mobile phlebotomy teams that travelled to individual fire stations, in coordination with an annual tuberculosis testing campaign for firefighters employed by OC Fire Authority (OCFA), and independently for firefighters employed by cities. We estimated seroprevalence and assessed several potential predictors of seropositivity. RESULTS: The seroprevalence was 5.3% among 923 OCFA personnel tested, with 92.2% participating. Among firefighters self-reporting a previous positive COVID-19 antibody or PCR test result, twenty-one (37%) did not have positive IgG tests in the current serosurvey. There were no statistically significant differences in demographic characteristics between cases and non-cases. Work city was a significant predictor of case status (p=0.015). Seroprevalence (4.8%) was similar when aggregated across seven city fire departments (42%-65% participation). In total, 1486°C fire personnel were tested. CONCLUSION: Using a strong serosurvey design and large firefighter cohort, we observed a SARS-CoV-2 IgG seroprevalence of 5.3%. The seroprevalence among OC firefighters in October 2020 was lower than the general county population estimated seroprevalence (11.5%) in August. The difference may be due in part to safety measures taken by OC fire departments at the start of the pandemic, as well as differences in antibody test methods and/or duration of antibody response.

Predicting Posttraumatic Stress and Depression Symptoms Among Frontline Firefighters in China.

To investigate the prevalence and comorbidity rate of potential posttraumatic stress disorder (PTSD) and depression in frontline firefighters in China, as well as to analyze the related predictive factors for PTSD and depression, our study included 261 firefighters who completed assessments including the Demographic Data Forum, PTSD Checklist for DSM-5, Center for Epidemiological Studies Depression Scale, Chinese version of Perceived Stress Scale, and Perceived Social Support Scale. Among the participants, 1.9% and 11.9% were identified as having potential PTSD and depression, respectively. There was a 9.1% chance of comorbid PTSD among the depressed firefighters and a 60% chance of comorbid depression among the firefighters with PTSD. Perceived stress positively predicted both PTSD and depression; perceived social support negatively predicted both PTSD and depression. Whereas family exogenous support predicted both PTSD and depression, family endogenous support only predicted depression. In addition, PTSD was predicted by rank. Soldiers and sergeants demonstrated higher level of PTSD than officers. Future studies on mental health of firefighters should take factors like perceived stress, social support, and rank into consideration.

Recovery Sleep versus Emotion Regulation in Predicting Fire Service Shift Workers Stress, Fatigue and Irritability.

Objective/Background: Fire service shift workers are at risk of developing mental health difficulties related to sleep loss and emotion dysregulation. We aimed to clarify the relationship between off-shift recovery sleep and emotion regulation on stress, fatigue and irritability. Participants: A total of 61 fire service shift workers (e.g. firefighter, captain, engineer, paramedic) on a "5/6" shift. Methods: Following five 24-hour shifts, participants reported on emotion regulation as well as daily sleep, stress, fatigue and irritability during six consecutive off-shift recovery days. Mediation analyses examined (1) emotion regulation as a predictor and sleep as a mediator of stress, fatigue and irritability outcomes; and (2) sleep as a predictor and emotion regulation as a mediator of stress, fatigue and irritability outcomes. Results: Greater self-reported total sleep time predicted lower recovery stress, fatigue, and irritability. Greater subjective sleep efficiency predicted lower recovery stress and fatigue, but not irritability. No significant relationships emerged for objective sleep or emotion regulation variables predicting stress, fatigue or irritability. There were no significant findings with either emotion regulation or sleep variables included as mediators. Conclusions: These findings suggest that stress management programs for fire service shift workers may be most effective when targeting sleep efficiency and quantity rather than emotion regulation strategies in the off-shift recovery period.

Coccidioidomycosis outbreak among inmate wildland firefighters: California, 2017.

BACKGROUND: In California, state prison inmates are employed to fight wildfires, which involves performing soil-disrupting work. Wildfires have become more common, including areas where Coccidioides, the soil-dwelling fungus that causes coccidioidomycosis, proliferates. However, work practices that place wildland firefighters at risk for coccidioidomycosis have not been investigated. METHODS: On August 17, 2017, the California Department of Public Health was notified of a cluster of coccidioidomycosis cases among Wildfire A inmate wildland firefighters. We collected data through medical record abstraction from suspected case-patients and mailed a survey assessing potential job task risk factors to Wildfire A inmate firefighters. We described respondent characteristics and conducted a retrospective case-control investigation to assess coccidioidomycosis risk factors. RESULTS: Among 198 inmate firefighters who worked on Wildfire A, 112 (57%) completed the survey. Of 10 case-patients (four clinical and six laboratory-confirmed), two were hospitalized. In the case-control analysis of 71 inmate firefighters, frequently cutting fire lines with a McLeod tool (odds ratio [OR]: 5.5; 95% confidence interval [CI]: 1.1-37.2) and being in a dust cloud or storm (OR: 4.3; 95% CI: 1.1-17.4) were associated with illness. Two of 112 inmate firefighters reported receiving coccidioidomycosis training; none reported wearing respiratory protection on this wildfire. CONCLUSIONS: Wildland firefighters who use hand tools and work in dusty conditions where Coccidioides proliferates are at risk for coccidioidomycosis. Agencies that employ them should provide training about coccidioidomycosis and risk reduction, limit dust exposure, and implement respiratory protection programs that specify where respirator use is feasible and appropriate.

Comparing cancer risk estimates using occupational record linkage approaches in male Florida firefighters.

BACKGROUND: Firefighters have an increased risk of cancer, but variations in reported results could be due to differences in occupational case ascertainment. This study compares cancer risk estimates generated by identifying firefighters from their occupational title available in the Florida Cancer Data System (FCDS) versus identification by a linkage method between the FCDS and the Florida State Fire Marshal's Office. METHODS: Florida firefighter employment records (1972-2012; n = 109,009) were linked with FCDS data (1981-2014; ~3.3 million records), identifying 3760 primary cancers in male firefighters. Using the FCDS occupational data field we identified 1831 male cancer cases in those classified as firefighters, first-line supervisors of firefighting and prevention workers, fire inspectors, emergency medical technicians, or paramedics. Age and calendar year-adjusted odds ratios (aOR) and 95% confidence intervals for firefighters versus non-firefighters were calculated for both groups. RESULTS: For skin cancers the risk estimate for FCDS-indentified firefighters was substantially lower than in the employment-record-linked firefighters (aOR = 1.06; 0.87-1.29 vs. 1.54; 1.37-1.73), but for endocrine system cancers it was greater (aOR = 2.36; 1.77-3.14 vs. 2.08; 1.71-2.53). Remaining cancer risk estimates were in the same direction for the two samples except for lymphoma (aOR = 1.10; 0.90-1.34 vs. 0.86; 0.75-0.99). CONCLUSION: Reliance on occupational title in cancer registry records to characterize firefighter cancer risk may result in estimates that are over- or underestimated depending on cancer site. The authors recommend moving toward national linkages between cancer registries and certification or other administrative records, which are a vital resource for firefighter cancer research.

Estimation of differential occupational risk of COVID-19 by comparing risk factors with case data by occupational group.

BACKGROUND: The disease burden of coronavirus disease 2019 (COVID-19) is not uniform across occupations. Although healthcare workers are well-known to be at increased risk, data for other occupations are lacking. In lieu of this, models have been used to forecast occupational risk using various predictors, but no model heretofore has used data from actual case numbers. This study assesses the differential risk of COVID-19 by occupation using predictors from the Occupational Information Network (O*NET) database and correlating them with case counts published by the Washington State Department of Health to identify workers in individual occupations at highest risk of COVID-19 infection. METHODS: The O*NET database was screened for potential predictors of differential COVID-19 risk by occupation. Case counts delineated by occupational group were obtained from public sources. Prevalence by occupation was estimated and correlated with O*NET data to build a regression model to predict individual occupations at greatest risk. RESULTS: Two variables correlate with case prevalence: disease exposure (r = 0.66; p = 0.001) and physical proximity (r = 0.64; p = 0.002), and predict 47.5% of prevalence variance (p = 0.003) on multiple linear regression analysis. The highest risk occupations are in healthcare, particularly dental, but many nonhealthcare occupations are also vulnerable. CONCLUSIONS: Models can be used to identify workers vulnerable to COVID-19, but predictions are tempered by methodological limitations. Comprehensive data across many states must be collected to adequately guide implementation of occupation-specific interventions in the battle against COVID-19.

The Influence of Heat on Daily Police, Medical, and Fire Dispatches in Boston, Massachusetts: Relative Risk and Time-Series Analyses.

Objectives. To examine the impact of extreme heat on emergency services in Boston, MA.Methods. We conducted relative risk and time series analyses of 911 dispatches of the Boston Police Department (BPD), Boston Emergency Medical Services (BEMS), and Boston Fire Department (BFD) from November 2010 to April 2014 to assess the impact of extreme heat on emergency services.Results. During the warm season, there were 2% (95% confidence interval [CI] = 0%, 5%) more BPD dispatches, 9% (95% CI = 7%, 12%) more BEMS dispatches, and 10% (95% CI = 5%, 15%) more BFD dispatches on days when the maximum temperature was 90°F or higher, which remained consistent when we considered multiple days of heat. A 10°F increase in daily maximum temperature, from 80° to 90°F, resulted in 1.016, 1.017, and 1.002 times the expected number of daily BPD, BEMS, and BFD dispatch calls, on average, after adjustment for other predictors.Conclusions. The burden of extreme heat on local emergency medical and police services may be agency-wide, and impacts on fire departments have not been previously documented.Public Health Implications. It is important to account for the societal burden of extreme heat impacts to most effectively inform climate change adaptation strategies and planning.

Firefighter occupation is associated with increased risk for laryngeal and hypopharyngeal squamous cell carcinoma among men from the Greater Boston area.

OBJECTIVE: Firefighters are exposed to a wide variety of carcinogens during the line of duty, including several associated with head and neck cancer. Existing studies assessing head and neck cancer risk with firefighting have predominately included occupational cohorts or registry data, which are limited by inability to adjust for smoking and alcohol consumption-major risk factors for head and neck cancer. Our objective was to assess the risk of head and neck cancer among men with an occupational history as a firefighter. METHODS: This work was conducted using male subjects from a large population-based case-control study of head and neck cancer from the greater Boston area using self-reported occupational history (718 cases and 905 controls). RESULTS: An occupational history as a firefighter was reported for 11 cases and 14 controls. Although no significant association was observed overall, we observed substantial increased risk for hypopharyngeal and laryngeal squamous cell carcinoma among professional municipal firefighters who had a light or no smoking history (OR=8.06, 95% CI 1.74 to 37.41), with significantly increasing risk per decade as a firefighter (OR=2.10, 95% CI 1.06 to 4.14). CONCLUSION: Professional municipal firefighters may be at increased risk for hypopharyngeal and laryngeal squamous cell carcinoma due to carcinogenic exposures encountered during the line of duty.

Cancer risks of firefighters: a systematic review and meta-analysis of secular trends and region-specific differences.

PURPOSE: The objective of this study was to conduct a systematic review and meta-analysis to evaluate the cancer risks among firefighters in the time course and from different geographical areas. METHOD: A PubMed search was performed to identify cohort studies about cancer risk and firefighting presented with standardized incidence ratios (SIRs) or standardized mortality ratios (SMRs). Using random-effect models, meta-relative risk estimates (mSIRs, mSMRs) and 95% confidence intervals (CI) were assessed. Cohort studies with employment starting before 1950 were classified as "old", studies starting between 1950 and 1970 as "medium", and later studies as "new". RESULTS: The general cancer risk of firefighters was similar to the general population, but mSMR decreased over time (new studies: mSMR = 0.81, 95% CI 0.70-0.92). We observed an increase of mSIR for melanoma of the skin and prostate cancer as well as a decrease of mSIR for stomach cancer with later employment onset. For those cancer sites, we did not observe a secular trend of mSMRs. Regional differences between relative cancer risks were particularly observed for bladder cancer. CONCLUSIONS: Among other things, innovative firefighting techniques and better personal protective equipment have provided a safer and healthier working environment for firefighters over time leading to a reduction of overall cancer incidence and mortality ratios. Increased general preventive medical checkups and possible additional screenings for firefighters might have led to more findings of malignant melanoma of the skin and prostate cancer in the recent past.

The relationship between the pattern of shift work and sleep disturbances in Korean firefighters.

PURPOSE: Sleep disturbances are prevalent in firefighters, but the relationship between patterns of shift work and sleep disturbances has not yet been investigated. Here, this relationship has been evaluated in Korean firefighters. METHODS: A cross-sectional study was conducted using an online questionnaire, which captured demographic, psychosocial and work-related characteristics. Sleep disturbance was assessed using the insomnia severity index (ISI). The relationship between insomnia and work-related factors (including type of shift work and the frequency of emergency events and off-duty work which means overtime work on off days) was analyzed. RESULTS: A total of 9810 firefighters completed the survey, representing approximately 21.5% of all Korean firefighters; data from 9738 subjects were included in the analysis. All firefighter roles were significantly associated with insomnia; the odds ratio (OR) was 2.456 (95% confidence interval [CI] 1.461-4.128) for fire suppression and 1.871 (95% CI 1.105-3.167) for the emergency medical services and rescue. However, the pattern of shift work did not show a statistically significant relationship. The OR increased along with the frequency of emergency events and off-duty work (p value for trend < 0.05). CONCLUSIONS: This study found a significant association between the frequency of emergency and off-duty work and insomnia in Korean firefighters, whereas the pattern of shift work showed no significant relationship. Therefore, measures to reduce the frequency of emergency and off-duty work are required to prevent sleep disturbances in firefighters.

Full employment history of Danish firefighters potentially involving additional exposures, 1964-2015.

BACKGROUND: This study aimed to demonstrate the possibility of using data on full employment history to describe occupational patterns of Danish firefighters that may indicate additional hazards encountered by these workers. METHODS: An established cohort of Danish full-time and part-time/volunteer firefighters was used in the study (N = 9952) as well as occupational history covering the period 1964-2015, which was retrieved from a nationwide pension fund with compulsory membership. The most frequently held employments other than firefighting, together with temporal patterns of these employments, were explored in descriptive analyses. RESULTS: Besides working in the firefighter service, both full-time and part-time/volunteer firefighters had frequently been employed in the military and the police (55% and 38%) and more than 10% of both types of firefighters in a number of blue-collar jobs, including construction-related jobs (eg, masonry, joining, carpentry, insulation, and installation), laundry and dry cleaning, the auto industry, and rubber and plastic production. Part-time/volunteer firefighters had more frequently been employed in the machine industry, fabricated metal production, the wood and furniture industry, and farming. Both types of firefighters were initially employed in other jobs before their employment in firefighting. CONCLUSION: The cohort of Danish firefighters had frequently been working in other professions potentially exposing them to additional hazardous exposures, and occupational patterns varied by type of firefighter employment. Accounting for full employment history is, for that reason, considered essential when exploring associations between specific professions and health outcomes.

Cancer risk among career male and female Florida firefighters: Evidence from the Florida Firefighter Cancer Registry (1981-2014).

BACKGROUND: Firefighters are at increased risk for select cancers. However, many studies are limited by relatively small samples, with virtually no data on the cancer experience of female firefighters. This study examines cancer risk in over 100,000 career Florida firefighters including 5000 + females assessed over a 34-year period. METHODS: Florida firefighter employment records (n = 109 009) were linked with Florida Cancer Data System registry data (1981-2014; ~3.3 million records), identifying 3760 male and 168 female-linked primary cancers. Gender-specific age and calendar year-adjusted odds ratios (aOR) and 95% confidence intervals for firefighters vs non-firefighters were calculated. RESULTS: Male firefighters were at increased risk of melanoma (aOR = 1.56; 1.39-1.76), prostate (1.36; 1.27-1.46), testicular (1.66; 1.34-2.06), thyroid (2.17; 1.78-2.66) and late-stage colon cancer (1.19;1.00-1.41). Female firefighters showed significantly elevated risk of brain (2.54; 1.19-5.42) and thyroid (2.42; 1.56-3.74) cancers and an elevated risk of melanoma that approached statistical significance (1.68; 0.97-2.90). Among male firefighters there was additional evidence of increased cancer risk younger than the age of 50 vs 50 years and older for thyroid (2.55; 1.96-3.31 vs 1.69; 1.22-2.34), prostate (1.88; 1.49-2.36 vs 1.36; 1.26-1.47), testicular (1.60; 1.28-2.01 vs 1.47; 0.73-2.94), and melanoma (1.87; 1.55-2.26 vs 1.42; 1.22-1.66) cancers. CONCLUSION: Male career firefighters in Florida are at increased risk for five cancers with typically stronger associations in those diagnosed younger than the age of 50, while there was evidence for increased thyroid and brain cancer, and possibly melanoma risk in female firefighters. Larger cohorts with adequate female representation, along with the collection of well-characterized exposure histories, are needed to more precisely examine cancer risk in this occupational group.

Physical training in the fire station and firefighters' cardiovascular health.

BACKGROUND: Few fire departments in Québec have a diversified health promotion programme. Yet, many allow firefighters to physically train during working hours. AIMS: To compare the weekly physical activity (PA) level and cardiovascular health indicators of firefighters who physically train on duty to those who do not. METHODS: Participants underwent a cardiovascular health assessment and completed an online questionnaire. RESULTS: One hundred and five full-time male firefighters participated in the study. Two groups were formed: firefighters who physically train while on duty (E, n = 64) and firefighters who do not (NoE, n = 41). Following statistical adjustments, off-duty weekly PA was not different between the two groups (E: 239 ± 224 versus NoE: 269 ± 249 min, P = 0.496); however, total weekly PA was higher (P = 0.035) in E (381 ± 288 min) than in NoE (274 ± 200 min). A difference was also observed in obesity prevalence measured with waist circumference (E: 9% versus NoE: 27%, P = 0.026) and in physical inactivity prevalence (E: 0% versus NoE: 27%, P < 0.001). After statistical adjustments, E firefighters have a significantly lower waist-to-height ratio than NoE firefighters (E: 0.51 ± 0.05 versus NoE: 0.54 ± 0.05, P = 0.017). CONCLUSIONS: Results show that firefighters who physically train while on duty have a higher total PA level on a weekly basis and have better cardiovascular health indicators. Our findings suggest that fire services should promote physical training while on duty to improve firefighters' cardiovascular health.

Population-based age adjustment tables for use in occupational hearing conservation programs.

Objective: In occupational hearing conservation programmes, age adjustments may be used to subtract expected age effects. Adjustments used in the U.S. came from a small dataset and overlooked important demographic factors, ages, and stimulus frequencies. The present study derived a set of population-based age adjustment tables and validated them using a database of exposed workers.Design: Cross-sectional population-based study and retrospective longitudinal cohort study for validation.Study sample: Data from the U.S. National Health and Nutrition Examination Survey (unweighted n = 9937) were used to produce these tables. Male firefighters and emergency medical service workers (76,195 audiograms) were used for validation.Results: Cross-sectional trends implied less change with age than assumed in current U.S. regulations. Different trends were observed among people identifying with non-Hispanic Black race/ethnicity. Four age adjustment tables (age range: 18-85) were developed (women or men; non-Hispanic Black or other race/ethnicity). Validation outcomes showed that the population-based tables matched median longitudinal changes in hearing sensitivity well.Conclusions: These population-based tables provide a suitable replacement for those implemented in current U.S. regulations. These tables address a broader range of worker ages, account for differences in hearing sensitivity across race/ethnicity categories, and have been validated for men using longitudinal data.

The Influence of Age on Firefighter Combat Challenge Performance and Exercise Training Habits.

Saari, AI, Renz, G, Davis, P, and Abel, MG. The influence of age on firefighter combat challenge performance and exercise training habits. J Strength Cond Res 34(9): 2500-2506, 2020-The primary purpose of this study was to compare older vs. younger physically trained structural firefighters' performance in an international firefighter physical ability competition (Scott Firefighter Combat Challenge) and their engagement in physical training. Secondarily, firefighters' perceived importance of fitness characteristics to perform occupational tasks was evaluated. Sixty-four trained male firefighters' completed a timed occupationally specific competition course and a survey to assess exercise habits and perceived importance of fitness characteristics to perform fireground tasks. Firefighters were stratified into younger (<37 years; n = 34) and older (≥37 years; n = 30) cohorts based on the sample's median age. Independent samples t-tests were used to analyze differences in outcome measures between younger and older cohorts. It took older firefighters 8.8% longer to complete the course compared with younger firefighters (p = 0.029). Both groups reported similar training frequencies of cardiovascular (CV) training (Younger: 4.1 ± 1.7 vs. Older: 3.6 ± 1.5 session·wk, p = 0.203) and strength training (Younger: 3.6 ± 1.2 vs. Older 3.2 ± 1.4 session·wk, p = 0.274). Furthermore, there was no difference in weekly training load for CV (p = 0.663) or strength training (p = 0.898) activities between the cohorts. On average, firefighters indicated that all fitness characteristics were at least somewhat important for occupational performance. Occupationally relevant competition performance among a sample of fit firefighters was lower in older firefighters compared with younger firefighters, despite similar self-reported training volume and intensity. Practitioners may expect age-related decreases in occupational performance despite performing similar amounts of physical training.

Total Energy Intake and Self-Selected Macronutrient Distribution During Wildland Fire Suppression.

INTRODUCTION: Wildland firefighters (WLFF) work long hours in extreme environments, resulting in high daily total energy expenditure. Increasing work-shift eating episodes and/or providing rations that promote convenient eating has shown augmented self-selected work output, as has regular carbohydrate (CHO) consumption. It remains unclear how current WLFF feeding strategies compare to more frequent nutrient delivery. Our aim was to determine WLFFs' self-selected field total energy intake (TEI), composition, and feeding patterns during wildland fire suppression shifts. METHODS: WLFF were deployed to fire incidents across the United States throughout the 2018 fire season. Preshift food inventories collected at basecamp provided item-specific nutrient content (kilocalories, CHO, fat, protein). Work shift consumption (TEI, feeding frequency, episodic composition) was monitored in real time by field researchers on fireline via observational data capture using mobile tablets. Shift work output was also quantified via actigraph accelerometry. RESULTS: Eighty-six WLFF (27.5±6.4 y; 16 female, 70 male) worked 14.0±1.1 h shifts, with a TEI of 6.3±2.5 MJ (1494±592 kcal) (51±10, 37±9, 13±4% for CHO, fat, and protein, respectively). WLFF averaged 4.3±1.6 eating episodes (1.4±1.3 MJ [345±306 kcal] and 44±38 g CHO·episode-1). WLFF who consumed >20 kcal·kg-1 averaged less sedentary activity than those consuming <16 kcal·kg-1. Data are presented as mean±SD. CONCLUSIONS: Not including fire camp meals (breakfast, dinner), the present work-shift TEI approximates 33% of previously determined WLFF total energy expenditure and demonstrates that current WLFF consumption patterns may not deliver adequate nutrients for occupational demands.

Career fire hall exposures to diesel engine exhaust in Ontario, Canada.

Firefighters are potentially exposed to many carcinogens while at fires. There is also concern that firefighters may be at risk of exposure to carcinogens at other times, such as exposure to diesel engine exhaust (DEE) within fire halls. The study objective was to evaluate DEE levels in career fire halls in Ontario, Canada. Twelve career fire halls from six cities across the province of Ontario, Canada were recruited. In each hall, 24-hr DEE area samples were collected using NIOSH method 5040 (modified) for respirable elemental carbon in three locations (vehicle bay, dormitory, living quarters). Sampling was conducted in both the summer and winter to assess seasonal differences. Factors that may influence DEE exposures were also collected including presence of local exhaust ventilation (LEV), emergency run data, vehicle bay design, and age of fire apparatus. LEV was assessed using a thermo-anemometer during both campaigns. Of the 69 samples collected, 16% had detectable elemental carbon concentrations, where all but one was taken within the vehicle bay (range: <0.5 µg/m3-2.7 µg/m3). The data indicates vehicle bay exposures may be higher in halls with LEV units, those that respond to more emergencies, have a back-in vehicle bay design compared to drive-through design, and during the summer season. Three samples (4.3%) exceeded the 1.03 µg/m3 proposed Dutch occupational exposure limit; however, the estimated exceedance fraction of the underlying vehicle bay exposure distribution was 17%. Eight halls had LEV units, where performance ranged from 3.6% to 85.3% (median = 54%) when compared to manufacturer recommendations. The results show that firefighters may be at an increased risk of exposure to DEE when in fire halls and that LEV units should be assessed regularly for efficiency. Although no occupational exposure limit for DEE is currently available for industrial/non-industrial workplaces in Ontario, fire departments should continue to implement DEE control strategies to reduce exposures to mitigate potential health risks. Additional exposure studies are recommended to better understand DEE exposure in fire halls.