A study released on Monday found that there was insufficient data to conclude that dust and pollution in the war zones of Iraq and Afghanistan, particularly from the burn pits used by the military to incinerate garbage, could cause long-term health problems in troops.

But the report, by the Institute of Medicine, an independent policy organization that is part of the National Academy of Sciences, did not rule out the possibility that the fine dust and particle matter found in Iraq and Afghanistan, combined with the smoke from burn pits, could cause serious illnesses or lung injuries in troops.

Rather, the report said time and again that “shortcomings in research and gaps in evidence” prevented it from reaching clearer conclusions. It recommended that the government undertake a long-term study of deployed troops to determine whether they develop respiratory problems, heart diseases or cancers that might be related to air quality in the war zones.

The report also suggested that “particulate matter” in the air, including windblown dust and vehicle pollution, might be a bigger health problem than burn pits. And though it found insufficient evidence to link air quality with an array of diseases, it did find “suggestive” evidence that exposure to a mixture of pollutants had reduced pulmonary function in troops — that is, had affected their ability to breathe.