Sunday, March 27, 2011

26/03 Radiation’s Enduring Afterglow

March 26, 2011

By GEORGE JOHNSON


Becquerels, sieverts, curies, roentgens, rads and rems. For all the esoteric nomenclature scientists have devised to parse the effects of nuclear emanations, the unit they so often fall back on is the old-fashioned chest X-ray.

Early in the crisis at the Fukushima Daiichi nuclear power plant in Japan, neighbors were informed with absurd precision that the radioactivity in a liter of their drinking water had risen to the equivalent of 1/88th of a chest X-ray. One day last week the air in Tokyo registered 0.155 of a microsievert an hour — another chest X-ray, if you were confined for a month at that level. Though stretched to the point of meaninglessness, the analogy is meant to soothe — balm for a spirit burdened by a century of living uneasily with radiation.

Measured by sheer fury, the magnitude 9.0 earthquake that damaged the reactors was mightier than millions of Hiroshima bombs. It shoved the northeastern coast of Japan eastward and unleashed a tsunami that wiped civilization from the coast. But explosive power comes and goes in an instant. It is something the brain can process.

With radiation, the terror lies in the abstraction. It kills incrementally — slowly, diffusely, invisibly. “Afterheat,” Robert Socolow, a Princeton University professor, called it in an essay for the Bulletin of the Atomic Scientists, “the fire that you can’t put out.”

Nuclear scientists speak in terms of half-life, the time it takes for random disintegrations to reduce a radioactive sample to half its size. Then a quarter, an eighth, a 16th — whether measured in microseconds or eons, the mathematical progression never ends.

When traces of radioactive iodine were found last week in the drinking water in Tokyo, officials expressed the danger in becquerels, the number of nuclear disintegrations per second: 210 per liter, safe for adults but high enough to warn that infants should not drink it. As the government began distributing bottled water, the level fell significantly but not the fear. As far away as California there was a run on fallout detectors.

As these hypothetical microthreats ate at the mind, rescue workers were piling up real bodies — 10,000 so far — killed by crushing waves or their aftereffects, deaths caused by gravity, not nuclear forces. These dead will be tabulated, mourned and eventually forgotten. The toll will converge on a finite number.

In Chernobyl, the site of the world’s previous big nuclear accident, the counting continues, like languid ticks from a Geiger counter. A United Nations study in 2005 concluded that about 50 people had been killed by the meltdown but that 4,000 would ultimately die from radiation-caused cancer — victims who do not know who they are. The most debilitating effect, one investigator said, has been “a paralyzing fatalism,” a malaise brought on by an alien presence that almost seems alive.

Radiation, before we had a hand in it, was just another phenomenon. Life evolved unknowingly in its presence, with rays from the sky and earth jostling chromosomes and helping to shuffle the genetic deck. When our brains evolved to the point where we could measure and summon the effect, the first reaction was not fear but fascination. The discoverers were revered as heroes. Then their names were converted into mathematical units.

William Roentgen produced the first artificial X-rays in 1895, tantalizing the world with see-through images of his wife’s hand, then Henri Becquerel found similar emissions coming unbidden from uranium. Isolating the first minuscule specks of radium, Marie Curie, the greatest of the pioneers (1 curie = 37 gigabecquerels), marveled that its eerie blue glow “looked like faint, fairy lights.” She was seeing the optical equivalent of a sonic boom — contrails of photons produced by speeding particles. Eager to see this new world for themselves, people purchased small brass eyepieces called spinthariscopes, named for the Greek word for spark. Mounted inside was a bit of radium bombarding a scintillating screen. Hold it to your eye and behold the tiny explosions. Spinthariscopes sat on parlor shelves next to stereoscopic postcard viewers and kaleidoscopes, items in a cabinet of curiosities.

Radiation was even supposed to be good for you. Vacationers soaked in radium hot springs. Magazines carried advertisements for radium suppositories, radium toothpaste and radium bread — quack products ranging from useless to harmful. As late as the 1950s, customers could peer inside their own feet through shoe store X-ray machines, the scientific way to ensure a perfect fit.

As more bona fide uses led to a medical revolution — X-rays for medical imaging, radium for killing rapidly dividing cancer cells — hints of danger gradually accumulated. In the 1920s, women who had painted glow-in-the-dark radium watch dials began to sicken and die. Around the same time, scientists experimenting with fruit flies showed that radiation causes genetic mutations — red eyes turned to white.

With Hiroshima, Nagasaki and above-ground testing, everything nuclear began to take on a more sinister air. But the threat still seemed distant and surreal. As mothers worried about strontium-90 from fallout insinuating its way into their children’s bones, they were reading “Atomic Bunny” comic books and sending in cereal box tops for the Lone Ranger Atomic Bomb Ring, a cheap plastic spinthariscope that promised a glimpse of “genuine atoms split to smithereens.”

For all the dread evoked by the stockpiling of nuclear weapons, it was the 1979 accident at Three Mile Island that marked an abrupt turn. Just days earlier, “The China Syndrome” had its cinematic release. The “backup systems to backup systems to backup systems” Jack Lemmon boasted about to Jane Fonda crumpled on the screen, adding to the anxiety over what was happening outside. In the end the partial meltdown was contained and the damage was mostly economic. A postmortem by the American Nuclear Society reported that the average dose to people living within 10 miles of the accident was 0.8 of a chest X-ray. But the name Three Mile Island never lost its afterglow.

In the meantime, Chernobyl has become a tourist destination. Visitors board a bus in Kiev and cross the border of the “zone of estrangement.” Avoiding the remaining hot spots, they see the ghost city of Pripyat and the ruined reactor. They can feed catfish swimming in a reactor cooling pond, and none of them have three eyes.

They might also see a resurgence of wildlife: moose, roe deer, Russian wild boar, foxes, river otter and rabbits. American ecologists who conducted a study of the area in the late 1990s concluded that for all the harm caused by fallout, the biggest impact from humans has been positive: their decision to pack up and leave. “Northern Ukraine is the cleanest part of the nation,” an official of Ukraine’s Academy of Sciences said at the time. “It has only radiation.”

Only radiation. That is small consolation for the evacuees in Japan and the workers, still dousing the reactors with hoses as though fighting a fire that could be put out.



George Johnson, a former reporter and editor at The Times, is author of "The Ten Most Beautiful Experiments." He is writing a book about cancer.

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