Limitations in existing studies and lack of quality data mean there's "insufficient evidence" to prove veterans' respiratory illnesses are caused by burn pit and other airborne hazard exposure in Afghanistan and Persian Gulf countries and a new approach is needed, experts said in a report released this week.
A committee of National Academies of Sciences, Engineering and Medicine researchers said better, more thorough studies are necessary to definitively link respiratory illnesses in troops and veterans to their exposure to burn pits and airborne hazards while deployed in the Southwest Asia Theater.
That doesn't mean there's no evidence suggesting exposures cause illnesses, though.
There was "limited or suggestive evidence" of a link between service in the Gulf War from 1990 to 1991 and for those who served in operations after Sept. 11, 2001, who experience "chronic persistent cough, shortness of breath and wheezing," according to existing data.
But it's not enough to definitively prove a connection without better studies, experts said.
“New approaches are needed to better answer whether respiratory health issues are associated with deployment. The current uncertainty should not be interpreted as meaning that there is no association – rather, the issue is that the available data are of insufficient quality to draw definitive conclusions,” said Mark Utell, a doctor and professor of medicine and environmental medicine at the University of Rochester Medical Center, and chair of the committee that wrote the report. “However, the committee believes it is possible – today – to conduct well-designed studies that will provide more clarity to veterans who are seeking to understand the respiratory problems they are experiencing.”
National Academies’ experts were tasked with sifting through existing research to determine if any had gathered sufficient evidence to prove that exposures caused respiratory illnesses and to identify gaps in knowledge about those exposures and how they affect troops and veterans deployed to those areas.
So far, VA only recognizes temporary health effects related to burn pits, including respiratory, skin, eye and gastrointestinal tract irritation.
Sverre Vedal, professor emeritus for the Department of Environmental and Occupational Health Sciences at the University of Washington School of Public Health, said the committee "experienced a general sense of frustration" during their work, as they heard testimonials from veterans and service members who said they experienced ill effects after their exposures.
"But the data did not support it," Vedal said, explaining again the limits of previous studies. "That was a frustrating aspect of our work on this committee. The data were not strong enough for us to conclude that there were associations."
Data on veterans and troops who experienced toxic exposures is frequently limited, since many veterans go undiagnosed, misdiagnosed or don't report their exposure, said Chelsey Poisson, National Guard medic, ER nurse and toxic exposure researcher at the Hunter Seven Foundation.
"If approximately 50% of Afghanistan veterans go to civilian providers and never use VA Medical Center services, how can the VA clinically account for a representative sample of the post-9/11 VA population?"
In limiting the scope of the review to respiratory illnesses, VA may miss other illnesses linked to exposures, Poisson said.
"We have to look beyond the respiratory diseases," she said. "If they looked at glioblastoma rates or prostate (issues), they’d probably see the seriousness of toxins on other organ systems."
The report, sponsored by the Department of Veterans Affairs, reviewed 27 respiratory health illnesses, including cancers, asthma, chronic bronchitis and sinusitis. Of those, "none met the criteria for sufficient evidence of an association with service" in those areas of operation.
Since 1990, researchers and VA estimate that more than 3.7 million American troops have served in the Southwest Asian Theater during operations including the Gulf War, stabilization period following the war and in post-9/11 conflicts.
Troops were met with exposure to airborne hazards including emissions from open burn pits, oil-well fire smoke, fine airborne particles, military vehicle exhaust -- including from diesel and jet fuel -- and industrial emissions causing local air pollution. Those exposures coupled with "extremes, stress and noise" those troops may have experienced could have "increased their vulnerability to these exposures," the report said.
But limited or flawed studies so far have in some ways crippled researchers reaching conclusive proof. Many of the completed studies assume that deployed veterans had the same types and levels of exposure, even though the types of hazards varied over time. What was torched in burn pits varied by conflict and location, for example.
As troops levels varied, Poisson said exposures increased and decreased, too. Research by the Hunter Seven Foundation showed that a majority of the veterans in Operation Iraqi Freedom suffered a more “severe” set of symptoms and complaints if they served in 2007, 2004 and 2005 (in that order), which "correlates with the increasing amount of combat in the country at the time. More combat equals more waste production, more combat-related exposures."
Several of the studies also failed to account for troops' smoking cigarettes, a known alternative cause to respiratory illnesses.
Mortality reports have also not done a thorough job of separating deaths caused by respiratory illnesses specifically, making it difficult for experts to determine "the extent of the harm" airborne exposures may have caused, including the number who have died because of it.
Existing studies also did not account for how factors such as race, gender and the location or timing of specific deployments could affect how service member and veteran exposures and illnesses. While some data on the timing and locations of deployed troops is available, advocates, researchers and vets have warned for years that the records are incomplete at best.
Toxic exposures have plagued troops likely as long as the American military has existed, and because the effects of those exposures may take time to fully manifest, experts have an even more difficult time tracking and linking them to illnesses vets may not develop until later in life.
National Academies researchers said in their report that "longitudinal studies" are needed to record a baseline lung function -- since troops are often at the peak of their lung function and in their early 20s when they deploy -- and then analyze how their lung function changes over time.
The Hunter Seven Foundation has collected that data in its research. Troops who deployed to Iraq from 2003 to 2011 with a 100% physical training (PT) pass rate had a 58% pass rate after deploying. While 5% of those reported shortness of breath while exercising before they deployed, 87% reported shortness of breath after they returned. About 20% reported having one chronic symptom before deployment (such as migraines, skin rashes, acid reflux or memory loss) compared to 95% after deployment.
Troops Hunter Seven collected data on who served in Afghanistan after 9/11 had a 99.7% PT pass rate before deploying. After, it was 89%. Before deploying, about 4.5% reported shortness of breath when exercising. After, nearly 47% reported shortness of breath. About 20% of the troops who served in Afghanistan reported having one or more chronic symptoms before deploying, which increased to 75% during the deployment and 89% after.
Researchers recommended that VA conduct updated and expanded studies of the deaths of veterans who served in Afghanistan and Persian Gulf countries, and compare veterans with higher and lower levels of exposure, instead of comparing exposed vets to the general civilian population. The last study was done in 2011.
"Through partnerships with other agencies, and the use of emerging exposure assessment technologies, VA could conduct or support well-designed studies that would yield more definitive answers," researchers said, urging VA to work with NASA, the National Oceanic and Atmospheric Administration (NOAA) and the National Insititute for Occupational Safety and Health to take advantage of their data and technology.
As VA prepares to launch its new, long-delayed electronic health record system that is intended to create a universal health record for troops during service and after, the report said researchers should have access to exposure information in that system.
In addition to its work with the Pentagon on programs such as the electronic health record system and the Individual Longitudinal Exposure Record (ILER) to track troops' exposures over time, National Academies' researchers recommended VA consider other partnerships to improve its data and studies.
Newly developed and emerging technology and techniques could also help researchers prove a connection between airborne exposures and illnesses, researchers said in the report. Newly discovered biomarkers, or "characteristics of the body that can be measured," could provide more information on those exposures, their effects on veterans' bodies and even how susceptible some people may be compared to others.
New developments in satellite data could also help researchers with more accurate estimates of past levels of airborne hazards, including burn pit emissions, the report said. Silicone wristbands have been created that could help troops detect their exposures in real-time. Portable "readers" are being developed that could help "map changes to the human genome" caused by exposures.
Read the National Academies' full report: