Missouri Sen. Claire McCaskill is pushing legislation she says is aimed at helping World War II veterans exposed to mustard gas.
McCaskill on Tuesday proposed requiring federal agencies to reconsider disability claims denied to those veterans.
The Democrat says the military tested the effects of mustard gas and the blister agent lewisite on about 60,000 service members by the end of WWII.
Those veterans were sworn to secrecy until 1991. McCaskill says some have struggled to receive compensation for health issues caused by exposure.
McCaskill's office says about 90 percent of applicants for benefits have been denied by the Veterans Affairs Department. They estimate a couple hundred veterans are still alive.
The VA says it recognizes that mustard gas exposure might have caused disabilities and will reach out to participants.