RICHLAND, Wash. — When Tim Snider arrived on Enewetak Atoll in the middle of the Pacific Ocean to clean up the fallout from dozens of nuclear tests on the ring of coral islands, Army officers immediately ordered him to put on a respirator and a bright yellow suit designed to guard against plutonium poisoning.

A military film crew snapped photos and shot movies of Mr. Snider, a 20-year-old Air Force radiation technician, in the crisp new safety gear. Then he was ordered to give all the gear back. He spent the rest of his four-month stint on the islands wearing only cutoff shorts and a floppy sun hat.

“I never saw one of those suits again,” Mr. Snider, now 58, said in an interview in his kitchen here as he thumbed a yellowing photo he still has from the 1979 shoot. “It was just propaganda.”

Today Mr. Snider has tumors on his ribs, spine and skull — which he thinks resulted from his work on the crew, in the largest nuclear cleanup ever undertaken by the United States military.