The testing has gone on for eight years now, and medical phenomenon Harold McCluskey knows the doctors will never be done with him. When he strips off his shirt next month for yet another examination at a nuclear decontamination center in Richland, Wash., he knows that scanning instruments will confirm his unwelcome distinction as the most radioactive person in the world, a 72-year-old man whose continued survival is something close to a miracle. On Aug. 30, 1976, McCluskey was gravely injured in an accident at the nearby Hanford Nuclear Reservation, absorbing in a few seconds 500 times the radiation doctors believe safe in a lifetime. “We told him then we’d never seen anything like it,” says Dr. Bryce Breitenstein, McCluskey’s physician then and now. “Each day that goes by is a big plus.”

On that late summer night McCluskey, then 64, had celebrated his 40th wedding anniversary with wife Ella before checking in for the midnight-to-8 a.m. shift at Hanford’s waste-recovery facility. There was another reason for his good mood: A five-month strike at the plant had just ended. McCluskey was to resume his job as a $16,000-a-year worker, producing a plutonium by-product called americium 241, a highly radioactive substance.

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Americium, which is used in ionization smoke detectors, was extracted within an airtight steel “glove box,” with McCluskey manipulating the controls from the outside. However, the vessel containing the active ingredient for the extraction process, americium-soaked resin, had remained in the cabinet throughout the strike.

McCluskey was uneasy about adding nitric acid to begin the extraction process. “They warned us when they built the plant,” he recalls. “If we tried the process when the resin was even three months old, it would blow up.” He called his boss and protested. “But when the boss called the powers that be, they said, ‘Go ahead.’ ” McCluskey, a soft-spoken, thoughtful man, did not walk out the door. “I’m not a gambler. When you’ve only got a 12th-grade education and you’ve put nearly 30 years in a job, and you’re facing retirement….”

At about 2:45 a.m. McCluskey heard an unfamiliar hissing noise that instantly chilled him. As the cabinet filled with dense brown fumes and the hissing intensified, he yelled, “The thing’s going to blow!” McCluskey was caught five feet from the blast. His protective rubber respirator was ripped from his face; hundreds of pieces of radioactive metal, leaded glass and rubber were blasted into his skin; acid seared his face, temporarily blinding him; and radioactive particles coated his body. Gasping for air, he inhaled quantities of the radioactive fumes, contaminating his lungs with the poisonous americium.

Covered with blood, murmuring “I can’t see,” McCluskey was dragged from the cubicle and put into an ambulance headed for the decontamination center. Too hot to handle, he was removed on arrival by remote control and transported to a steel-and-con-crete isolation tank.

Blinded, his hearing damaged by the explosion, McCluskey spent the next three weeks at the unit cut off from personal contact. Monitored, like an alien, by nurses wearing respirators and protective clothing, he could neither see nor clearly understand the attendants who approached. “It all sounded like gibberish to me,” he says. For nearly a month after the explosion, his family could come only within 30 feet of him. “You can imagine what kind of conversations we had,” Ella, 72, says with some irritation.

During the next five-and-a-half months, McCluskey’s deep Baptist faith sustained him as doctors laboriously extracted tiny bits of glass and razor-sharp pieces of metal embedded in his skin. “Of nine doctors, four thought I had a 50-50 chance,” he remembers. “The rest just shook their heads.” Through October he was exhaling measurable amounts of americium with each breath. Nurses scrubbed him down thrice daily and shaved every inch of his body every day. The radioactive bathwater and thousands of towels “are still somewhere at Hanford,” he says. “You can’t bury them or throw them away.” The stoic McCluskey also withstood some 600 shots of zinc DTPA, an experimental drug that helped him excrete the radioactive material—though for a while, McCluskey says, the shots made his left arm look “like a knotty pipe.”

When he finally returned home on Valentine’s Day, 1977, McCluskey encountered a different pain. In his hometown of Prosser, he was known as “the atomic man.” Some fearful friends called and said, “Harold, I like you, but I can never come to your house.” For months, McCluskey rotated his haircuts among several barbers. “I didn’t want anyone’s business to be hurt,” he explains.

He showed the same grace and tolerance as his radiation-related medical problems proliferated terrifyingly. He had a kidney infection, four heart attacks in as many months and cataract surgery on both eyes, followed by a cornea transplant and a precipitous drop in his blood platelet count, which required transfusions.

Today McCluskey has virtually no stamina. He is unable to hunt, fish or do any of the things he planned for his retirement. He listens to the Bible on tape and tends his rose garden. His scars, wispy white hair and watery blue eyes make him look 15 years older than he is. His body still emits sufficient radioactive waves to set off a Geiger counter when he runs it over his face. “He still has about 10 times as much americium 241 as is found in a smoke detector,” explains Earl Palmer, a health physicist who monitors him.

An investigation into the explosion confirmed that the resin mixture had become unstable exactly as McCluskey had warned. He sued the Energy Research and Development Administration for $975,000, settling in 1977 for $275,000 plus lifetime medical expenses. Even then, according to Ella, the government balked at paying up. A feisty former teacher and nurse, she took over: “I told them they wouldn’t be able to do an autopsy when he died. They said that wasn’t fair. Then they paid.”