More than two decades after the Sept. 11 attacks, the health consequences are still unfolding for tens of thousands of people exposed to toxic ash, debris and dust near ground zero.

Now, the World Trade Center Health Program, the federal program that provides critical medical care for those affected, is at risk of losing funding.

Barry Locke, from Long Island, says the program must be protected.

Locke was working downtown in Manhattan during the 9/11 attacks. Less than a week after the towers fell, he was told it was safe to return to his office — just one block from ground zero.

“We were told it was safe to go back,” Locke recalled. “Every time you came outside, that smell, a stench I can still taste in my mouth.”

Like many others who spent time in Lower Manhattan in the days and weeks following the attacks, Locke was later diagnosed with a 9/11-related cancer. “A lump in my throat or my neck,” he said.

His story echoes thousands of others. According to U.S. Sen. Kirsten Gillibrand, nearly 50,000 people have now been diagnosed with cancers linked to 9/11 exposure.

Speaking publicly this week, Sen. Gillibrand urged lawmakers to fully fund the World Trade Center Health Program as part of any upcoming funding package.

Established in 2011, the program provides medical monitoring and treatment to first responders, survivors, and others exposed to hazardous materials during and after the attacks. But it now faces a projected $3 billion funding shortfall over the next 15 years.

In response, both Democratic and Republican leaders from the region are calling for immediate action to ensure the program continues to serve those in need.

Locke, who has applied to the program, says it’s a lifeline for thousands and could be for many more in the future.