(NewsNation) — Senate Republicans reversed course and voted against a bill that was supposed to assist veterans that have been affected by the toxic chemicals in burn pits.

The PACT Act, which the House passed earlier this month, would enable additional healthcare coverage for more than three million veterans who were exposed to toxic burn pits and Vietnam-era veterans exposed to the deadly herbicide Agent Orange.

“During the OEF and OIF wars, government contractors burned up to 227 metric tons of hazardous waste at forward operating bases using jet fuel in large ground pits,” according to Burn Pits 360, a non-profit group that advocates and helps veterans suffering from problems caused by exposure to burn pits. “Items burned included: batteries, medical waste, amputated body parts, plastics, ammunition, human waste, animal carcasses, rubber, chemicals, & more.”

Veterans who have been exposed to these dangerous chemicals in burn pits on duty can suffer from devastating health conditions including neurological disorders, pulmonary diseases, rare forms of cancer, and many unexplained symptoms and even death.

Senate Republicans, 25 in total, blocked the measure to these suffering veterans, after originally agreeing to support it. Some speculate that the GOP is retaliating against Joe Manchin after he struck a deal with senate majority leader Chuck Schumer relating to the “Inflation Reduction Act of 2022.”

“The more charitable explanation is that 30 Republicans just changed their mind. That three weeks ago they thought it was a good bill, helping veterans was a good idea, and three weeks later they decided that it wasn’t a good idea…” Sen. Chris Murphy, D-Conn., said in a statement. “The less charitable explanation is this, Republicans are mad that Democrats are on the verge of passing climate change legislation and have decided to take out their anger on vulnerable veterans. Because that’s the other thing that’s changed in the last three weeks.”

“There is no question that it’s a bad look (for the GOP),” said Niall Stanage, associate editor for The Hill. “And it’s a bad look for several reasons.”

Stanage says one of the reasons is that this bill was meant to help millions of veterans.

“Sometimes I think people look at these small groups of protestors and can think we are talking about maybe a couple hundred, or a couple thousand veterans,” Stanage said. “This affects 3-million veterans.”

Stanage doesn’t buy the Republican explanation for opposing the legislation either, which he says is a labyrinthine issue that has to do with spending and how spending is classified.

“There is an old saying in politics, that if you’re explaining – you’re losing,” Stanage said. “I think that applies here, because the clear message of this bill is: It’s a bill to help veterans get healthcare to which they’re entitled.”

Sen. Pat Toomey, R-Penn., said on the Senate floor that he didn’t support the bill because it would create $400 billion in unrelated spending, which he called a “budgetary gimmick.”

“My concern about this bill has nothing to do with the purpose of the bill,” Toomey said. “This budgetary gimmick is so unrelated to the actual veterans issue that has to do with burn pits, that it’s not even in the House version of this bill.”

The senate republicans who voted against the bill are Sens. Ted Cruz, Joni Ernst, John Barrasso, Marsha Blackburn, Bill Cassidy, John Cornyn, Tom Cotton, Kevin Cramer, Deb Fischer, Bill Hagerty, Josh Hawley, Cindy Hyde-Smith, Jim Inhofe, Ron Johnson, John Kennedy, Roger Marshall, Mitch McConnell, Rob Portman, Roy Blunt, Mike Braun, Ben Sasse, Tim Scott, Rick Scott, Dan Sullivan and Todd Young. Sens. Additionally, Sens. Steve Daines and Roger Wicker voted against the bill after not voting in June.

The Hill contributed to this story.