Scientists weigh in on Fukushima radiation reaching coast

Photo illustration by Daniel K. Lew

When the roof came off Japan’s Fukushima nuclear power plants in March 2011, releasing toxic amounts of radioactivity into the environment, Californians felt safe knowing the disaster was unfolding more than 5,000 miles away across the Pacific.

However, the same ocean that separates us from Japan also connects us, and radioactive waters that have been riding a current for more than three years are expected to wash ashore some time this year.

While scientists anticipate substantial dilution of the radiation in the world’s largest body of water, the potential health effects cut to the heart of the contemporary scientific debate on the biological consequences of low-level radiation.

“(The radiation) is still a small number, whether you multiply it by 10 or by 100, at levels we expect,” said Dr. Ken Buesseler, senior scientist with the Center for Marine and Environmental Radiation at the Woods Hole Oceanographic Institution in Massachusetts.

“A lot of people are dismissive of it because it’s so low, and that’s not a good thing to do because radiation can kill … It doesn’t necessarily mean it’s at harmful levels because I can measure these very, very small amounts.”

Buesseler is leading an effort to collect and analyze water samples at 36 beach sites along the West Coast from Alaska down to Scripps Pier in La Jolla. Samples are collected quarterly, and Buesseler will know exactly when irradiated waters from Fukushima hit the coast by the type of radiation-emitting element — or radioactive isotope — found.

While some reports place their arrival at Southern California this summer, Buesseler said all estimates are based on computer models that can’t pinpoint details.

“These models are designed to look at the entire Pacific — 5,000 miles — not about specific conditions at La Jolla or Black’s Beach,” he said. “It’s a little harder to predict right at the beach exactly when we’ll see it. We know it’s out there and we know it’s moving slowly across ... I tell people by the end of the year we should start to see it along the coastline, at least in the San Francisco area and up.”

Professor Kai Vetter of the Nuclear Engineering Department at UC Berkeley has been monitoring radiation levels in the air and rainwater around Berkeley as well as in the soil, milk, cheeses and animal feed from nearby farms since the 2011 disaster.

With numerous sources of daily radiation already in the natural environment, Vetter expects the concentration of radiation in the tainted Pacific Ocean to be 1,000 to 10,000 times less than the radioactive isotope (potassium-40) found in kelp or bananas.

“People don’t understand nuclear radiation and the impact,” said Vetter. “Everyone is really scared of it, even though it’s part of the world we’re living in.

“The bottom line is, the concentration we expect to see here is the ocean water in California is extremely small. It should not pose any health risk on swimmers, divers, people on the beach.”

Experts project the radioactivity will be very low, about two to 20 times greater than the residual radiation already in the Pacific from the nuclear weapons tests of the 1950s and ’60s. Yet just as no doctor recommends smoking even though a lone cigarette never killed anyone, no scientist will suggest that more radiation is good for you.

Effects are cumulative

Dr. Herbert Abrams of Stanford University’s School of Medicine was a principal in the six-year Biological Effects of Ionizing Radiation VII study for the National Research Council released in 2005. He testified before Congress about its conclusions.

Abrams says any additional radiation, even at low doses, comes on top of the radiation people receive from natural backgrounds and from the more than 550 million medical and dental radiological exams given annually in the United States.

“The underlying premise that has to be considered ... is that the effects of radiation are cumulative,” Abrams said. “They add up over time. The question is, what is the turning point? And that’s why the common sense is to avoid radiation as much as you can.”

The effect of radiation on living tissue depends on the strength of the radiation and the length of exposure. Even at the anticipated strength of a thousandth of an airport X-ray, the accumulated exposure will be greater if one is in the water longer than the few seconds it takes to be X-rayed.

The radiation from Fukushima is predicted to peak a year after its arrival and to linger for a year after that. Abrams said the potential dose should not be dismissed as negligible.

“Am I concerned? Yes, I am,” he said. “And that’s because I know radiation pretty well. I’ve been training (medical) residents for 60 years and part of that training is a respect for the effects. It shakes up the cell and it goes after the genetic material ... The bottom line is that (radiation) is a carcinogenic agent.”

Most at-risk

Women, children, and particularly the unborn, are more vulnerable to radiation’s effects. However, everyone agrees that we’ll never know definitively whether any cancers have been caused by the coming radioactive waters.

That’s because three in 10 Americans will develop cancer over their lifetime anyway. It would take a massive epidemiologic study, requiring years of research and millions of dollars, to trace any cancer back to the low-level radioactive waters from Fukushima.

And none are being proposed.

“Any additional radioactivity can cause an increase in risk,” said Buesseler. “It’s there, we just can’t measure it. ... If a kid gets thyroid cancer and is exposed to high levels of iodine-131 (a radioactive isotope), you could make a connection. But you can’t put these smaller risks and doses and make the connection to anyone’s specific cancer and what they were exposed to.”

Bottom line?

So what is the risk of swimming, surfing and splashing about in the low-level radioactive waters for the next two years? Abrams has more than a passing familiarity with much of the scientific literature on the subject since the advent of atomic energy in 1945.

“There’s been so much done in this area that has produced some acceptable conclusions, but they’re population conclusions and it’s very hard to bring them down to a level of an individual,” he said. “I mean, you can just say, ‘There is increased risk.’ But how do you translate that into an understandable discussion of what’s going to happen to guys on their surfboards? I don’t know.”

Buesseler notes that higher levels of radioactivity than expected here are still being measured in the aftermath of the Chernobyl disaster in the Baltic Sea, where millions live, work and play.

“It’s very, very difficult to see the effects of low-level radioactivity,” he said. “Now, you could switch that around and say, because it’s so hard, it can’t be a million times worse, right? We can’t be hiding something from the public that this is a thousand times worse than we’re telling you, because you would see it then. You’d see it in populations.”

With uncorroborated claims and preposterous predictions floating around the Internet and elsewhere, the coming radioactive waters still might produce health problems unrelated to the radiation, Vetter warns.

“The psychological stress and psychological impact which might actually cause health effects, we should never underestimate that,” Vetter said. “And that’s really what the big problem is, because there’s a lot of fear. There are a lot of claims out there to increase the fear. From my perspective, it is completely unjustified and irresponsible to claim all the effects because that will just cause more and more fear in the public, which is probably the biggest impact.”

However, Abrams issues his own warning about those scientists declaring the low-level radiation to be absolutely “safe” based on a viewpoint that he says isn’t completely science. “Physicists, or at least some of them, are the people in the nuclear industry itself,” said Abrams. “They play down (the risks) at such low doses, but they never talk about it as being cumulative.”

With risks that can’t be quantified and consequences that won’t be verified, the radioactive waters coming to the coast this year seem to fit in the category of activities, products and habits that no one can label “healthy.”

“Keep the exposure to radiation down,” Abrams said. “But you’ve got to go on living and doing your thing, and if that thing is just riding the waves, the joy and the pleasure probably exceed the risk.”