US President Joe Biden in his first Veterans Day in office announced an effort to better understand, identify and treat medical conditions that troops face due to toxic environments. Biden’s son Beau was an Iraq war veteran.

His efforts focus on lung problems suffered by troops who breathe in toxins and the potential connection between rare cancers and time spent overseas breathing poor air, according to the White House.

His announcement comes as he was traveling to Arlington National Cemetery in Virginia on Thursday to participate in a wreath-laying ceremony and deliver remarks.

Biden’s efforts are also designed to make things easier for veterans to make claims based on their symptoms.

“We’re discovering there is a whole host of lung conditions related to deployment,” said Dr. Richard Meehan, an immunologist and rheumatologist.

The retired US Naval Reserve officer, who served in the Mideast during the 1990s and again in 2008, is co-director of the Denver-based National Jewish Health Center of Excellence on Deployment-Related Lung Disease.

Biden hinted at a potential link between his son Beau’s death from an aggressive form of brain cancer after returning from Iraq and his exposure to toxins in the air. There’s no scientific evidence to suggest that link.

Beau Biden‘s death was a defining moment for Joe Biden. The younger Biden deployed from October 2008 until September 2009 as a captain in the Delaware Army National Guard. In 2013, he was diagnosed with a tumor, and he died two years later at age 46.

“When you compare them to another group, you have to compare them to another healthy, fit group,” Meehan said. “That’s one of the problems overlooked in surveys that have shown no higher incidence of cancer.”

The new rules will allow veterans to make claims within 10 years of service.

The US military has been aware of health risks associated with open-air burn pits. In 2013, investigations found that a military camp in Afghanistan operated a pit for more than five years. This is four times longer than what Pentagon rules allow.

(With inputs from Associated Press)