September 04, 2025
3 min read
Key takeaways:
- Inhalation exposures from heavy equipment maintenance significantly heightened the likelihood for dyspnea and wheeze.
- The odds for wheeze significantly rose with aircraft maintenance inhalation exposures.
Inhalational exposures during routine military heavy equipment maintenance and aircraft maintenance heightened the odds for wheeze, according to results published in JAMA Network Open.
“Clinicians should broaden their evaluation of veterans presenting with respiratory symptoms,” Reza Hosseini, MD, MPH, assistant professor of family medicine at Upstate University Hospital, medical director of Central and Eastern New York Occupational Health Clinical Center and researcher collaborator at Yale University School of Medicine, told Healio.
“It’s important to consider the full range of occupational exposures across all periods of military service,” he continued. “Routine duties, even outside combat zones, may carry substantial inhalational risks and should be factored into clinical assessments to better identify exposures that increase the risk of chronic lung disease.”
In a cross-sectional study, Hosseini and colleagues evaluated 1,712 U.S. veterans (median age, 37.4 years; 88.9% men; 68.9% white) who served in the Army (59.4%), Marine Corps (23.4%), Air Force (15.7%) or mixed/other (1.3%) between Oct. 7, 2001, and Feb. 28, 2017, to determine the link between military inhalational exposures during non-wartime routine activities occurring outside theaters of conflict and chronic respiratory symptoms of dyspnea, wheeze (in past 12 months) and bronchitis.
The study classified outside the theater of conflict as “any active duty military service that did not involve deployment to these countries [Afghanistan, Kyrgyzstan, Iraq, Kuwait, Qatar, the United Arab Emirates or Djibouti] during [a period when these deployments were in areas of conflict], including time spent during military training, maintenance of equipment or other nonwartime military service.”
Notably, the lack of information on exposures outside the theater of conflict prompted this research, Hosseini told Healio.
“While there has been increasing recognition of respiratory risks from burn pits and deployment-related exposures in U.S. military veterans, we noticed a critical gap: most military service occurs outside combat zones, often involving substantial exposure to airborne hazards — such as those encountered during vehicle and aircraft maintenance,” Hosseini said.
“We launched this study to examine whether these routine, non-deployment exposures might also contribute to lasting respiratory symptoms,” he continued.
Included veterans were deployed to Afghanistan or Southwest Asia, had active-duty military service outside deployment in the theater of conflict and lived near one of the six Veterans Affairs sites, according to the study.
Using veterans’ responses to a multi-item questionnaire inquiring about 29 exposures related to active-duty military service time when not deployed, researchers obtained data on exposure prevalence and duration.
The 29 exposures went down to 20 items in factor analysis and were grouped into one of the following categories: heavy equipment maintenance (three items), aircraft maintenance (five items), construction (three items), combustion and ground dust (five items) and incineration byproducts (four items).
The study highlighted that 77 months was the median length of total active-duty military service, and the majority of service time was spent outside the theater of conflict (median, 63 months; 82.8%).
The most prevalent chronic respiratory symptom was wheeze (15.2%), followed by chronic bronchitis (7.1%) and dyspnea (7%). In terms of inhalation exposures, researchers found that combustion and ground dust exposure was reported by the highest proportion of veterans at 59.2%. Aircraft maintenance was the second most frequently reported exposure category at 47.4%, followed by heavy equipment maintenance at 45.7%, construction at 12.4% and incineration byproducts at 7.2%.
After adjusting for age; sex; race and ethnicity; income; marital status; education; BMI; smoking status; civilian vapors, gas, dust or fumes exposure; and deployment duration, the study reported that heavy equipment maintenance exposure significantly heightened the likelihood for dyspnea (adjusted OR = 1.33; 95% CI, 1.06-1.68) and wheeze (aOR = 1.29; 95% CI, 1.1-1.52). The odds for wheeze also significantly rose with aircraft maintenance inhalation exposure (aOR = 1.22; 95% CI, 1.01-1.47).
“Despite the heightened focus on burn pits and deployment-specific exposures, we found that inhalational exposures from routine service outside the theater of conflict — such as heavy equipment and aircraft maintenance — were significantly associated with chronic respiratory symptoms such as dyspnea and wheeze,” Hosseini told Healio. “These results point to important and underrecognized sources of respiratory risk.”
For the three remaining inhalation exposure categories, researchers observed no significant links to any of the evaluated respiratory symptoms.
“Our findings emphasize the need for ongoing exposure surveillance and prevention efforts across all areas of military service, not just in combat zones,” Hosseini said. “Reducing harmful inhalational exposures during routine operations may play a key role in protecting long-term respiratory health of veterans.
“We hope this work will prompt further research into potential non-wartime military hazardous exposures to support future prevention strategies and safeguard the health of service members,” he told Healio.
Additionally, Hosseini said capturing lung function testing and diagnostic outcomes in this population will be needed in future studies.
“Importantly, we aim to assess the cumulative inhalational exposure burden across the entire span of military service activities,” Hosseini told Healio. “This more comprehensive approach will help us better understand long-term risks and guide effective prevention.”
For more information:
Reza Hosseini, MD, MPH, can be reached at reza.hosseini@yale.edu.
Perspective
Hosseini et al bring much‐needed attention to active‐duty military exposures that occur outside theaters of conflict — areas often overlooked in both research and clinical practice. Their approach is notable: to my knowledge, this is the first study to quantify total non‐deployed active‐duty time while capturing a wide spectrum of potentially hazardous exposures. The application of factor analysis improves interpretability and offers clinicians a practical framework for incorporating these histories into patient care.
While the findings are not unexpected, their significance lies in identifying tasks and duties often unique to military personnel — activities that, while distinct from those in other industries, generate exposures known to be hazardous in other occupational settings. Future work could also examine exposures tied to living conditions on base, such as contaminated water, mold or asbestos, which may be particularly relevant to this population.
My team’s work has focused on deployment‐related and occupational exposures outside of the military but has not systematically assessed hazards encountered during non‐deployed service. The present findings underscore the value of including these exposures in epidemiologic studies and clinical evaluations.
Although the authors adjusted for deployment duration, future work incorporating comparable wartime exposure variables from the parent SHADE study could clarify differences between those with high‐intensity deployment exposures and those without, while accounting for other active‐duty hazards. Linking these exposure variables that have been developed with lung function or other objective outcomes would further strengthen these important observations.
Lauren M. Zell-Baran, PhD, MPH
Disclosures: Zell-Baran reports no relevant financial disclosures.
Sources/Disclosures
Collapse
Disclosures:
Hosseini reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.
