Edwards was one of 60,000 enlisted men enrolled in a once-secret government program -- formally declassified in 1993 -- to test mustard gas and other chemical agents on American troops. But there was a specific reason he was chosen: Edwards is African-American.

"They said we were being tested to see what effect these gases would have on black skins," Edwards says [...]

According to declassified records and reports published soon after, three types of experiments were done: Patch tests, where liquid mustard gas was applied directly onto test subjects' skin; field tests, where subjects were exposed to gas outdoors in simulated combat settings; and chamber tests, where men were locked inside gas chambers while mustard gas was piped inside.