Thousands of military personnel who served in Iraq and Afghanistan were exposed to a variety of potentially harmful substances, including the smoke produced by the burning of waste on military bases.

Now U.S. Sen. Amy Klobuchar is sponsoring legislation that would create a national center to study the effects of burn pits on veterans and members of the military.

The issue will take on increased importance as more veterans of recent wars show increased rates of cancer, asthma, emphysema, and even rare lung disorders. Exposure to dust and burn pits also has been shown to cause insomnia and high blood pressure.

Klobuchar, a Minnesota Democrat, and U.S. Sen. Thom Tillis, R-N.C., have introduced the Helping Veterans Exposed to Burn Pits Act. It would create a center within the U.S. Department of Veterans Affairs for the prevention, diagnosis, mitigation, treatment, and rehabilitation of health conditions relating to exposure to burn pits.

During the Mideast wars, the military disposed of item such as plastics, aerosol cans, electronic equipment, human waste, metal containers, tires, and batteries by throwing them into open pits, sometimes dousing them with jet fuel, and setting them ablaze. It was common for smoke from these open-air burn pits to waft through the entire base and into living areas.

The VA already has established a burn-pit registry to get a handle on the scope of the potential problem. The registry allows eligible veterans and service members to document their exposures and report health concerns through an online questionnaire.

Those eligible must have served in Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn; in Djibouti, Africa, on or after Sept. 11, 2001; in Operations Desert Shield or Desert Storm; or in southwest Asia on or after Aug. 2, 1990.

As of three weeks ago, 65,320 veterans and service members had completed and submitted the registry questionnaire.

Lesson learned?

In an interview Monday, Klobuchar said the VA and the Pentagon seemed to have learned a lesson from the illnesses that arose from exposure to Agent Orange defoliant in the Vietnam era, when vets who complained of being sick were dismissed for a long time before the problem was finally acknowledged.

"For years they were in denial and finally the VA and Congress is setting aside money [for] the health effects of Agent Orange. We don't want to make the same mistake with this issue," Klobuchar said.

"There were dozens of these burn pits, so different people were exposed to different things. Maybe some may be fine and some people may be predisposed, but until they register and get a sense of what their symptoms are, they're not going to be able to trace what really happened."

An initial study on the health impacts of burn pits was inconclusive. But last year, the federal chief watchdog for Afghanistan reconstruction issued a report saying that the Pentagon had put the health of U.S. troops at risk by not following regulations on solid waste disposal, along with burning prohibited items in Afghanistan.

Once established, the center would conduct research on such things as clusters of illnesses for various burn pits, and would share best practices with doctors on how to diagnose and treat the illnesses.

"Right now no one quite knows what's going on except knowing there seems to be a common problem," Klobuchar said. "We'd want them to be using the data they've collected, instead of just having it sit somewhere."