Respiratory Health Effects of Airborne Hazards Exposures in the Southwest Asia Theater of Military Operations (2020) / Chapter Skim
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5 Challenges and Opportunities for Advancing the Understanding of Respiratory Health Issues in Southwest Asia Theater Veterans
5 Challenges and Opportunities for Advancing the Understanding of Respiratory Health Issues in Southwest Asia Theater Veterans
Pages 193-234
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From page 193... ...
Specifically, it requested that the committee "pay particular attention to hazards associated with burn pit exposures" and use the results of its comprehensive review to "identify knowledge gaps, research that could feasibly be conducted to inform the field and generate answers, newly emerging technologies that could aid in these efforts, and organizations that VA might partner with to accomplish this work." The committee combined several sources of information to accomplish this task. These included its review of the studies of health outcomes in theater veterans (presented in Chapter 4)
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From page 194... ...
Previous National Academies Reports Addressing the Health Effects of Exposure to Burn Pit Emissions The third volume of the report series Gulf War and Health contained a comprehensive review of the literature addressing the association between exposure to fuels, combustion products, and propellants present in the 1990–1991 Gulf War theater and health outcomes (IOM, 2005)
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From page 195... ...
It did find limited or suggestive evidence of an association between exposure to combustion products and reduced pulmonary function in the study populations, but it was unable to determine whether the long-term health effects were likely to result from service members exposed to emissions from burn pits -- specifically the one in operation at Joint Base Balad -- because high ambient concentrations of PM from both natural and anthropogenic sources likely modified the effects, but could not be accounted for or adjusted in the analyses. Therefore, that committee concluded that the long-term health risk of airborne toxicants, burn pit, and other related exposures was not clearly defined.
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From page 196... ...
, they do yield some information about the constituents and ambient levels of airborne toxicants that may have been present on bases with burn pits. A 2011 review of the monitoring efforts at Joint Base Balad conducted by a committee of the Institute of Medicine (IOM, 2011)
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From page 197... ...
Major Toth said he recalled seeing during his time in theater a number of types of items in burn pits, including plastics, metal/aluminum cans, rubber, chemicals such as paints and solvents, petroleum, oil, lubricant products, munitions, unexploded ordnance, wood waste, and incomplete combustion byproducts, with jet fuel (JP-8) being used as the accelerant.
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From page 198... ...
Concern over burn pit exposures is understandable, given their prominence as a source of smoke, vapors, gases, and fumes in military facilities where large numbers of service members were present as well as the known toxic effects of the byproducts of combustion of the materials that were burned in them. To date, though -- other than the self-reported airborne exposures and health information collected as part of such efforts as the Millennium Cohort Study and the Airborne Hazards and Open Burn Pit Registry -- there have been no large-scale systematic data collection or maintenance efforts focused on the effects of exposure to burn pit emissions.8 There are means, though, to gain a better understanding of this issue.
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From page 199... ...
This and the following sections of this chapter discuss but do not present comprehensive assessments of the scientific literature regarding the many potential avenues for future research that VA could conduct or foster -- an undertaking outside the committee's Statement of Task. Gaps in Knowledge Concerning Adverse Respiratory Health Outcomes in Theater Veterans Although there have been a number of studies of respiratory health outcomes in veterans of the Southwest Asia conflicts, the committee found that there was inadequate or insufficient information from which to draw a conclusion about the association between in-theater airborne exposures and several outcomes.
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From page 200... ...
. Burn pits were later supplemented with or replaced by incinerators at some larger installations, which further complicates the evaluation of exposures over time, given the lack of emissions monitoring.
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From page 201... ...
• Recent advances in research indicate that there are biomarkers associated with service in the Southwest Asia theater and specific exposures found in that theater. Biomarkers research is addressed in greater detail later in the chapter.
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From page 202... ...
In tackling this element of the Statement of Task, it considered not just research that would directly help to answer outstanding questions but also initiatives that would generate data that could be used in the future to move the field forward. Research Addressing Constrictive Bronchiolitis and Excess Mortality In the course of its work, the committee identified a number of opportunities to advance knowledge on issues related to respiratory health outcomes related to airborne exposures in Southwest Asia theater veterans.
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From page 203... ...
The most recently published study of 1990–1991 Gulf War veterans, which did include mortality from COPD or from respiratory system diseases in general, used 2004 as its cutoff date (Barth et al., 2016)
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From page 204... ...
as well as of the other factors mentioned above. Given this, the committee recommends that VA conduct or sponsor an updated analysis of total and respiratory disease mortality in Southwest Asia theater veterans.
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From page 205... ...
military and veteran populations have made use of administrative data that for the most part do not rely on self-reports, such as data from the DoD Manpower Data Center (which includes a roster of all military personnel and deployments) , the Armed Forces Health Surveillance Branch (which contains deployment information)
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From page 206... ...
Ongoing and new experimental toxicology studies using appropriate animal models and relevant exposure scenarios should also be encouraged. Outcomes in Susceptible Subpopulations As previously noted, almost no information exists on whether particular subpopulations may be at greater risk for respiratory health problems associated with Southwest Asia theater exposures.
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From page 207... ...
. Using Military Biorepository Information in Epidemiologic Studies Epidemiologic studies of respiratory health effects of airborne hazards exposures in the Southwest Asia theater most often rely on qualitative proxies for exposure, such as deployment status (deployed versus nondeployed)
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From page 208... ...
Given the potential costs of such an expansion, a reasonable first step might be a pilot program that would collect samples of different biologic media and then assesses their suitability for informing specific questions of health outcomes. For example, military personnel who served in theater could be stratified by their exposures, focusing on those with the lowest and highest potential exposure to particular airborne hazards in order to maximize the signal to noise ratio.
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From page 209... ...
Research Addressing the Mechanisms of Effects of Airborne Exposures Knowledge is lacking on how measured levels of environmental contaminants in serum, tissue, and the like translate to biologic effects and, separately, health outcomes. Among the areas of research of greatest relevance to studies of the health of theater veterans are basic science studies addressing biologic mechanisms and also those examining the biomarkers of effect and susceptibility.
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From page 210... ...
The committee thus believes that it would be desirable and feasible to expand the knowledge base by conducting further toxicologic studies using exposure parameters that realistically reflect the experience of those who have served in the Southwest Asia theater. Such studies should focus on inhalation studies of the primary airborne exposures of concern -- burn pit emissions and PM from indigenous sources such as ambient dust and sand -- and should mirror the composition, size, and concentration of these identified by exposure characterization research.
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From page 211... ...
Biomarkers of Exposure Research The complex composition of Southwest Asia theater airborne contaminants means that there are few data in the medical literature to help understand the half-lives of those contaminants in humans. However, trace elements absorbed and retained in the biopsied lung tissues or other biospecimens (serum and urine, for example)
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From page 212... ...
. The committee suggests that a feasibility study for constructing a specific job-exposure matrix for airborne hazards be considered as an exposure assessment tool.
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From page 213... ...
. Coupled with the locations of military bases and camps, MODIS active fire detections could assist in pinpointing the locations and assessing the durations of historical burn pits on or near in-theater operations.
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From page 214... ...
-- a scenario that is arguably more relevant to the 1990–1991 Gulf War exposure setting. It is in contrast to the approach taken by many of the COPD studies examined by the committee that were based, at least implicitly, on what is known about the relationship between cigarette smoking and COPD, where the disease develops over a long time period and is associated with an extended history of exposure.
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From page 215... ...
Observations Regarding the Illustrative Study Designs The two designs developed by the committee would address many of the flaws identified in the epidemiologic studies reviewed in this report. However, there are reasons why such approaches have not been implemented by the research teams who have been and are trying to understand whether in-theater airborne exposures are resulting in adverse respiratory health outcomes in the Southwest Asia theater veterans.
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From page 216... ...
NEWLY EMERGING TECHNOLOGIES TO ADDRESS KNOWLEDGE GAPS Previous sections of this chapter have already identified many of the major technologies that will help to better characterize airborne exposures in Southwest Asia theater veterans. These include satellite measurements of PM, other pollutants, and burn pits -- combined with advances in data processing -- to estimate past ambient levels, biomarker discovery (including the algorithms that allow for the rapid screening of candidates)
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From page 217... ...
The committee understands that, as of early 2020, elements of this RFI have been initiated. If such technologies were to be developed and implemented in the future, they would not only inform retrospective exposure assessments but would also generate information that field commanders and medical support personnel could use to lower exposure potential by, for example, limiting outdoor missions or elective activities or providing personal protective equipment on "high exposure" days.
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From page 218... ...
(2016) assert that the linking of DMSS data with other information resources "provides a powerful epidemiological resource that allowed us to investigate the relationship between deployment burn pit exposures, serum biomarkers, and potential health outcomes." However, there is a major obstacle to fully exploiting DMSS information: the lack of an interoperable DoD–VA EHR and the subsequent difficulties in combining active-duty and post-service medical data held by the departments.
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From page 219... ...
. The 2018 National Academies publication Feasibility of Addressing Environmental Exposure Questions Using Department of Defense Biorepositories: Proceedings of a Workshop -- in Brief highlighted additional biorepositories that hold materials that may be of use in studies of Southwest Asia theater veterans (NASEM, 2018a)
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From page 220... ...
Researchers Conducting Studies of Theater Veterans' Health There are a number of epidemiologic studies and research centers that address respiratory health issues in Southwest Asia theater veterans. Some of these are under the guidance of VA investigators -- the Airborne Hazards and Burn Pits Center of Excellence; the Comparative Health Assessment Interview, Million Veteran Program, National Health Study for a New Generation of U.S.
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From page 221... ...
The National Academies 2018 report Gulf War and Health: Volume 11 noted this potential. While it was referring to research on the generational health effects of theater exposures, its observations are also applicable to respiratory health effects: [T]
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From page 222... ...
The adverse effects of airborne exposures on staff and their families is of great concern to the department,21 which has partnered with the Environmental Protection Agency to establish and manage the AirNow Department of State program.22 AirNow has real-time and historic ozone and PM2.5 measurements for a number of locations, including Kabul, Afghanistan; Manama, Bahrain; Bagdad, Iraq; Kuwait City, Kuwait; and Abu Dhabi and Dubai, United Arab Emirates. While they are single-site observations, they provide a means for validating other measurements and proxies used in exposure characterization and epidemiologic studies.
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From page 223... ...
. Other Nations Involved in the Southwest Asia Theater of Military Operations A coalition of nations have taken part in military operations in the Southwest Asia theater since 1990.
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From page 224... ...
2016. Environmental air sampling near burn pit and incinerator operations at Bagram Airfield, Afghanistan.
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From page 225... ...
2016. Contractors sickened by military burn pits left to fend for themselves.
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2019b. Open burn pit report to Congress.
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From page 227... ...
2019. Respiratory health after military service in Southwest Asia and Afghanistan.
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Presentation before the Committee on the Assessment of the Department of Veterans Affairs Airborne Hazards and Open Burn Pit Registry.
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From page 229... ...
Presentation before the Committee on the Respiratory Health Effects of Airborne Hazards Exposures in the Southwest Asia Theater of Military Operations. October 3, 2019.
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From page 230... ...
2017. Assessment of the Department of Veterans Affairs Airborne Hazards and Open Burn Pit Registry.
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From page 231... ...
2012. The effects of exposure to documented open-air burn pits on respiratory health among deployers of the Millennium Cohort Study.
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From page 232... ...
Presented to the Committee on the Respiratory Health Effects of Airborne Hazards Exposures in the Southwest Asia Theater of Military Operations. October 3, 2019.
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From page 233... ...
2018. Small airways disease in an Operation Desert Storm deployer: Case report and review of the literature on respiratory health and inhalational exposures from Gulf War I
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