(NewsNation) — Retired U.S. Army Sgt. Maj. Kevin Bittenbender re-entered civilian life in 2018 but four years later, exposure to toxic burn pits from his tour overseas would lead to the amputation of his left leg.

He’s one of the millions of veterans who attribute persisting ailments to exposure to burn pits while they served in the United States military.

In August of last year President Joe Biden signed the PACT Act, adding more than 20 new presumptive conditions for burn pits and other toxic exposures, granting more people like Bittenbender access to health care through the U.S. Department of Veterans Affairs.

Veterans say there’s still room to improve, but the changes the law ushered in are noticeable.

Since the law’s passage, the VA has approved more than 300,000 PACT Act claims, according to a dashboard on the agency’s website.

“I believe a lot more people have signed up,” Navy veteran Kevin Simon said. “I do believe the level of care has gone up.”

While both Simon and Bittenbender are happy to see healthcare access expanding for veterans, both men said information seems to be spreading largely by word of mouth.

That’s despite a VA digital marketing campaign specifically for PACT Act awareness. According to the agency’s website, people interacted with the campaign more than 772 million times.

“I heard on the radio about veterans dying, (and to) sign up for the benefits,” Simon said. “So I was impressed with that. I haven’t seen any TV ads. And I believe that’s what the VA should do.”

Simon uses his own podcast, “Gulf War Side Effects,” to get the word out, too. There, he’s built up a network of veterans who share information about the roadblocks they’ve encountered and how they got around them.

“I just want the Americans to understand what the vets are really going through,” Simon said.

Proving their ailments were linked to burn pit exposure was a major obstacle in the way of health care coverage for veterans before the PACT Act.

Veterans say anything from documents and batteries to plastics and human waste were burned in the pits they manned while serving overseas. The chemicals they inhaled would surface as skin conditions, breathing difficulties and cancer later in life.

Fortunately for Bittenbender, his doctor was familiar with the veteran’s previously documented burn-pit ailments, including neuropathy that caused both pain and numbness in his hands and feet.

“They said, ‘it’s definitely your exposure to these toxins that are in your system,’” Bittenbender said.

Now that the bill is law, providers have conducted more than 4 million toxic exposure screenings between September and July and more than half of claims for the five most frequently cited conditions were granted, according to the VA’s website. The most common condition was hypertensive vascular disease.

But getting to this point has been a long time coming.

“It took a lot of patience on my part because there was a lot of aggravation before the PACT Act with trying to link ailments to burn pits,” Bittenbender said.

The passage of the act wasn’t a sure thing, even up to the last minute. Congress was poised to pass their bill about a week sooner, but before veterans could celebrate, 25 Republican senators changed their votes from yes to no. They blamed Democrats for including a budget “gimmick” that they said could divert billions away from veteran issues.

The PACT Act passed in the Senate the following week, 86-11.

One year later, with support from his family, a nonprofit called Hope for the Warriors and encouragement from his surgeon, Bittenbender has plans to compete with a handcycle in multiple marathons this year, and already has completed one.

“The VA is very understanding it, but again, patience plays a large part…” Bittenbender said. “I tell my soldiers that if you do not get the answer that you’re seeking, ask for a second (opinion).”

In accordance with the PACT Act, the VA is expected to provide continuing education to healthcare professionals to help identify, treat and assess illnesses caused by burn pits.