Radiation: Is the threat real?

BOSTON — Nearly three weeks after Japan’s earthquake-tsunami-nuclear accident, the news from the Fukushima Daiichi power station remains stubbornly dismal. As workers struggle to restart vital cooling systems, their efforts are confounded by new, elevated levels of contamination.

At one reactor on Tuesday, leaking water contained radiation so high that just three minutes of exposure would match the maximum annual dose for a U.S. nuclear worker.

Already, Fukushima has released about 160,000 times more radioactive iodine than the Three Mile Island accident, according to the Institute for Energy and Environmental Research, a nonprofit nuclear watchdog. And the risk could get worse. The station’s three damaged reactors and four out of control spent fuel pools “contain far more long-lived radioactivity, notably cesium-137, than the Chernobyl reactor,” according to the institute.

“While the releases are still considerably below Chernobyl, they have already reached a level that could affect the region around the site for a prolonged period,” said the institute’s president, Arjun Makhijani, in a press release.

If you’re a resident of the United States, so far there’s little reason to worry about the nuclear accident. On Tuesday, U.S. officials reported that trace levels of radiation from the accident were detected across the country, but at infinitesimal levels that wouldn’t cause health risk, the Wall Street Journal reported. Barring a massive, Chernobyl-style explosion, for now the biggest danger appears largely confined to Japan, and particularly to the brave workers struggling to tame radioactive fuel. Seventeen of them have been exposed to excessive levels of radiation, according to the World Health Organization.

Yet no matter the risks, Fukushima reminds us that radiation is a villain unique in its ability to discomfort and confuse us, a foe that leaves us anxious and defenseless in unparalleled ways.

Radiation frightens us — perhaps irrationally — because it is at once evil and amorphous. Unlike a terrorist organization or a hostile army, we can’t threaten, attack or defend against it. We can’t even see, smell, feel or taste it. We’re largely deprived of tangible information about its whereabouts, and so we struggle even to understand it.

Nuclear accidents like the one in Japan are strange, slow moving monsters, unlike anything else in the human experience. Right at this moment, Fukushima Daiichi is the site of a savage, man vs. machine battle, in which billion dollar mechanical beasts must be calmed, cooled and controlled. Destroying them is no option. The longer the battle, the hotter they get, the more they take out their ire on their containment vessels and cooling ponds. As these self destruct, they becme ever more mortal, rendering the struggle increasingly hostile for the humans trying to nurture them back from the brink.

For the rest of us, away from this apocalyptic battlefield, an accident like Fukushima unfolds in eye-glazing snippets of largely useless data. Let’s face it: Officials charged with keeping us abreast of the matter might as well be speaking in some alien tongue. Whether they’re discussing the latest contamination in seawater, drinking water or food, all we can glean is a vague sense that things aren’t as they should be, a sentiment they temper with anodyne assurances that any exposures from this “serious accident” are inconsequetial. They “pose no immediate risks” so we should “try not to panic,” as Japanese government spokesman Yukio Edano repeatedly assures us (without telling us why he’s informing the world of a risk that doesn’t exist).

At times, the data points tell us less about the health risks, and more about how hapless those charged with controlling the Fukushima beast have become. In one such atypically useful disclosure, officials stated this week that, “Workers fled from a stricken reactor as radiation readings spiked at 10 million times normal levels,” as London’s Daily Mail reported. That data point was unusually easy to digest: 10 million is a big number, and we could visualize workers speeding off in trucks, suggesting a major risk. But officials later apologized for misinforming the public, clarifying that the radiation levels were only 100,000 times normal. How could they be off by a factor of 100? (Imagine a weather forecast with a mistake like that.) And what does this say about the other measurements they report?

The communication breakdown stems in no small part from a deep lack of objectivity, and a fatal conflict of interest. The people with the education and equipment needed to identify radiation risks are nuclear scientists and utility executives, from Tepco in this case. They’re also the ones we’re least inclined to trust, given that they have a vested financial and personal interest in assuring us that we’re safe.

Isn’t this a bit like trusting bank robbers to let us know what’s in the vault?

Making matters worse, we’re unlikely to detect any deceit from these nuclear industry officials, because of radiation’s stealth modus operandi. Brave workers fighting to tame the reactors stare down the prospect of acute radiation sickness that could kill in days, weeks or months. But for everyone else, the risk is longer term and less traceable. The lethal isotopes travel many miles from their source, via food, air and water. If we contract cancer a decade from now, tracing it back to Fukushima is (and almost certainly will continue to be) beyond the capability of science.

Our bodies readily welcome hostile radioactive molecules, mistaking them for friendly nutrients. Our cells can’t easily distinguish the calcium that makes our bones strong from strontium-90 and radium-26. So those radionuclides collect in our skeletons, causing bone cancer and leukemia.

Likewise, the human thyroid gland — which regulates key body functions like metabolism and energy levels — needs iodine to function, just as a car needs oil. But the thyroid can’t distinguish stable iodine from the volatile variety that has now spilled into the Pacific and spread through the provinces surrounding Fukushima. So it bonds with both.

Once radiation has entered into our cells, there’s no way to neutralize it. Of course radioactive isotopes have a half life, meaning that they degrade with time. But as that happens, they emit rays and particles that tamper with our genetic material — the very blueprints of life — potentially causing cancer in us, and harming the prospects of future generations as well.

Infants and children are the most vulnerable, because their growing bodies — replete with dividing and multiplying cells — offer greater opportunity for disruptions.

“The primary risk of concern with iodine-131 is thyroid cancer, with children more at risk than adults,” explains IEER’s Makhijani. “Young girls are at greater risk than boys. Female infants have a risk of thyroid cancer 70 times greater than adult males for the same radiation exposure.” Some airborne radioactive iodine-131 from Fukushima will settle on land, including pastures. “When contaminated grass is eaten by cows and goats, iodine-131 concentrates in milk. It has a half-life of about eight days, meaning that appreciable amounts will remain in the environment for a few months after large releases.”

On the other hand, defenders of the nuclear industry are fond of assuaging our concern by reminding us that radioactivity is a daily fact of life.

They are, unfortunately, half correct. True, radiation is ubiquitous. People get very tiny doses from granite countertops, bananas and the sun. Long flights expose travelers to a slightly higher than normal level of cosmic rays. And if you share a bed with a partner, you also increase your exposure ever so slightly from natural radioactive carbon that decays over time — just another factor to consider when assessing whether the benefits outweigh the costs of the companionship.

The doses are higher if you live with a smoker. The lung cancer risk from cigarettes emerges not only from tar and nicotine but also from significant doses of radioactive lead and polonium that they emit. The housemates of a pack-and-a-half-per-day smoker receive the equivalent of 12 chest X-rays each year in extra radiation each year, by one estimate. (The EPA has a simple dose calculator you can use to calculate your exposure.)

Your radiation dose is also affected by where you live. In Ramsar, a village in northwestern Iran famous for its hot springs, the local bedrock emits doses as much as 100 times greater than normal — a fact that makes it of particular interest to scientists attempting to understand chronic low-level radiation exposure. Lying on some beaches in Brazil — where the sand includes radioactive mineral called monazite — can expose you to radiation up to 400 times the normal background levels in the United States.

But don’t let that reassure you. Currently, scientists presume that there is no safe dose of radiation — that any exposure, including what we get from the sun and earth, increases the likelihood of adverse impacts. Scientists have not yet mastered the art of teasing out exactly how many cases of cancer, birth defects and mental retardation emanate from radiation versus other toxins. While the health effects of chronic, low-level exposure remain poorly understood, there is a “convincing case” that such exposure is harmful, according to research led by the International Atomic Energy Agency.

“Just because it is natural doesn’t mean it is safe,” writes Makhijani. “Cobra venom is natural. Aflatoxins in peanuts are natural. Death is natural. Does that mean it’s OK for our neighbors to punch us? According to the National Academies and other detailed studies by official investigations, the best science is: low dose, low risk; high dose high risk. Zero risk is at zero dose,” he argues.

Of course, risk-free life doesn’t exist, so it’s essential to keep the danger in perspective. For now in North America, scientists say that the contamination that already exists in your home or doctor’s office is far more harmful than fallout from Fukushima.

A CT scan, for example, delivers a dose ranging from one year to 15 years worth of background radiation. Scientists recently estimated that the 70 million CT scans performed in 2007 would add 29,000 cancers, about half of which would be fatal. Two-thirds of them would afflict women. So while the benefits of medical imaging dramatically outweigh the drawbacks, the risk is by no means negligible.

Better yet, if you wish you could do something about the risk, consider radon gas, the second-biggest cause of lung cancer in America. It claims 21,000 lives each year according to EPA estimates. Radon emerges from naturally-occurring uranium in the soil and water in much of North America (particularly in the Rocky Mountain, Midwest and Appalachian states). It builds up in well-insulated homes. As usual for this sinister foe, radon is invisible and odorless, so there’s no way you’d know it’s there.

The good news: Unlike Fukushima, there’s something that you can do about radon. Get your home tested, and fix it if you have a problem. You may save a family member from a painful and premature death.

Follow David Case on Twitter: @DavidCaseReport