Congress has passed a proposal pushed by Missouri Sen. Claire McCaskill that's aimed at helping World War II veterans she says were exposed to mustard gas by the military.
McCaskill told reporters Thursday that the measure will show veterans that the government believes them and could help them get benefits.
Senators sent the proposal to President Donald Trump as part of another bill to expand college aid for military veterans.
McCaskill says it will require the government to reconsider disability benefits denied to those who claim the testing caused health problems.
She says the military tested mustard gas and the blister agent lewisite on about 60,000 veterans. But those tested were sworn to secrecy until 1991.
McCaskill says some have struggled to receive compensation for health issues resulting from exposure.