WASHINGTON — A Department of Veterans Affairs official on Wednesday drew the ire of some House lawmakers during a hearing over the agency’s continued resistance to providing health care to more service members and veterans for toxic exposure, stating more data is needed to conclude exposure leads to illnesses such as cancer.

“More scientific investigation is needed to enable VA and [the Defense Department] to perform a reliable assessment of the possible or known long-term adverse health effects,” said Dr. Patricia Hastings, chief consultant for post-deployment health services at the VA.

But recently declassified Defense Department documents show the Pentagon knew troops were exposed to multiple toxins and hazards that have led to hundreds of cancer cases and dozens of dead veterans after deploying to the Karshi-Khanabad Air Base, known as K2, in Uzbekistan in the early days of the War on Terror.

Some lawmakers responded harshly to the VA’s stance during the hearing of the House Oversight and Reform Committee’s subpanel on national security.

“The VA’s continued denial has left hundreds, if not thousands, of K2 veterans ineligible for certain preventative health programs and unable to receive VA disability benefits in connection with their service at K2,” said Rep. Stephen Lynch, D-Mass., chairman of the committee’s subpanel. “This is an injustice that must be rectified, and [VA] Secretary [Robert] Wilkie has the authority to fix it by granting presumptive status to K2 veterans today.”

K2 is a former Soviet air base in southeastern Uzbekistan that shares a border with northern Afghanistan. After the 9/11 attacks, U.S. forces established Camp Stronghold Freedom at K2, which was used to support combat missions from 2001 to 2005. Veterans have described a toxic environment at the post, where pond water glowed green, black sludge oozed from the ground and the government posted massive white and yellow signs warning troops to keep out of certain areas due to chemical agents.

Lawmakers argued during the hearing that the VA isn’t providing presumptive care, which it has the authority to do without approval from Congress or the White House. Lawmakers agreed conclusive research is needed, but the evidence is increasing that young veterans got sick after deploying to K2. And it isn’t just K2, thousands of veterans have been exposed to burn pits all over the world, most notably Iraq and Afghanistan, and VA has denied nearly 78% of those claims as well.

Former service members who spent time at K2 testified on Capitol Hill in February that they were aware of at least 400 individuals diagnosed with cancers who served at the base. They said at least 30 have died.

During a health assessment test in 2001 by the Defense Department, military analysts found the base had “elevated levels of volatile organic compounds and total petroleum hydrocarbons were detected at numerous locations throughout Stronghold Freedom, including tent city, eastern expansion area and adjacent to the aircraft maintenance facility.” It also found ambient air is the “main concern for environmental contaminants.”

The assessment found that “inhalation of vapors from exposed, subsurface fuel contaminated soils could potentially cause adverse health effects to personnel at Stronghold Freedom if sufficient exposure circumstances occurred.” As a result, the assessment recommended “prohibit digging into soil contaminated with jet fuel,” but those areas were populated with aircraft hangars and tents in which soldiers slept.

An area near the tents was found to contain pieces of depleted uranium in 2001, and external radiation measurements in 2002 detected elevated radiation levels. K2 also had open-air burn pits used to get rid of waste, which the VA has posted on its website “may affect the skin, eyes, respiratory and cardiovascular systems, gastrointestinal tract and internal organs.”

Yet, VA officials remain unconvinced and said the issue needs more science to back up veterans’ claims for health care and disability compensation.

Hastings said the agency is still studying the K2 mission and how it might have impacted the health of troops serving there. She said the study will take about 12-18 months to complete. She added the study is being conducted with a “very small staff.”

“Good science takes time ... it will take some time,” she said.

Hastings also noted the Defense Department made efforts to reduce health risks at K2.

“Remediation efforts were completed to reduce potential exposure and risk to service members deployed there. In accordance with environmental science best practices, DoD covered contaminated areas with clean dirt and declaring them ‘off limits’ to prevent mitigate the threat of radiation hazard and fuel,” Hastings said.

But lawmakers said they are losing patience with the VA, which took decades to provide care for victims of Agent Orange exposure during the Vietnam War. Lawmakers said they fear toxic exposure is the post-9/11 generation’s Agent Orange and questioned who would criticize opening up presumptive care.

“The downside is maybe one of these veterans got cancer from somewhere else and they’d be covered, I’d absorb that risk,” Lynch said. “If that’s the downside for the government here, embrace it...Don’t deny them all for the misplaced concern a couple of veterans with cancer might get the treatment that might not be connected to service at K2.”

Lynch and Rep. Glenn Grothman of Wisconsin, the ranking Republican on the subpanel, penned a letter to Wilkie to request a senior VA official testify at the K2 hearing, which the department declined to do. The lawmakers said while they appreciate Hastings’ medical expertise, she has no role in crafting VA policy and determining eligibility for benefits.

“Hundreds of veterans have been diagnosed with various forms of cancer and other health ailments since deploying to K2 between 2001 and 2005. We believe these veterans deserve to hear directly from VA leadership about why the department continues to deny that their illnesses are service-connected despite the growing evidence to the contrary,” the letter reads.

Some veterans advocates said they believe toxic exposure is likely to be a top issue in President-elect Joe Biden’s administration since he believes his son Beau Biden’s brain cancer was caused by burn pit exposure in Iraq when he deployed there as a part of the Delaware National Guard. The issue has gained more public attention after comedian Jon Stewart has started to lead the lobbying effort to get care to veterans suffering from illnesses linked to toxic exposure.

beynon.steven@stripes.com Twitter: @StevenBeynon