The ocean looked remarkably clear the week of a recent hot spell. Waves reached out and pulled back against the sand in rhythmic succession.
Avid beachcombers suggest that in two to five years, those waves will stretch onto West Coast beaches and leave behind broken and waterlogged wreckage from the recent tsunami in Japan. That’s about the amount of time it will take for the wind to drive the waves to bring the first bits of remnants here. The process can continue for several years beyond that.
The same winds pushing debris on the tides have been bringing over something a little less tangible, but possibly more troublesome.
Isotopes of iodine, cesium, and even strontium—spewing from a damaged nuclear reactor—have hit our shores and made it across the country. By most accounts, their levels—found in milk, air, water, rainwater, and even produce samples—have been low and deemed safe by the U.S. Environmental Protection Agency (EPA), despite, in some cases, being above the maximum allowable limit. As time has passed since the initial disaster, the levels picked up by monitoring stations have continued to drop—so much so that the EPA announced on May 3 that it’s halting its increased monitoring.
Does that mean the radiation risk is no longer something to worry about? That we’ve got a clean atmosphere, food, and water supply in the United States? The short answer is yes, but take that “yes” in light of the fact that we’re all at risk from any number of ills beyond radiation, like second-hand smoke, a car crash, or a meteor falling from the sky.
It’s a matter of percentages.
Some people argue that background radiation levels are low, so an average adult would have to be exposed to excessive amounts to match what he or she is regularly exposed to from nature. Others argue that no level of radiation—especially manmade radiation—is safe.
Everyone pretty much agrees, however, that there’s no need to run out and stock up on potassium iodide or to eliminate certain foods from a regular diet. But there’s also some consensus that continual exposure to low-level radiation likely has some impact on health—even if that impact is uncertain.
Across the sea
As beachgoers look out over the Pacific Ocean on a brilliant Central Coast day, it might be hard to believe that beyond the horizon the Unit 2 reactor at the Fukushima Daiichi Nuclear Power Plant in Japan continues to puff out plumes of radioactive smoke. Or that ocean water around the plant contains extremely elevated levels of radioactive isotopes.
According to the EPA, fewer of those radioactive isotopes are reaching our shores.
On May 3, the EPA released a statement citing that consistent decreases in radiation levels across the United States prompted the agency to halt its heightened monitoring.
“After a thorough data review showing declining radiation levels related to the Japanese nuclear incident, EPA has returned to the routine RadNet sampling and analysis process for precipitation, drinking water, and milk,” the statement said.
The EPA will continue to use its RadNet radiation monitoring system—made up of more than 100 stationary monitors—to get near-real-time data on the slightest fluctuations in background radiation levels. It’s simply halting the additional mobile monitors set up since March and their frequent monitoring.
The EPA will also continue monitoring milk, drinking water, and rainwater samples, with the next sampling set to take place in three months. The statement said the EPA is ready to accelerate radiation sampling and analysis if the need arises.
The agency didn’t define what that “need” would be, but many experts have said that—short of another big disaster at the plant—there’s no need to be alarmed in the United States. Some say that even residents of Japan—short of the population in the immediate vicinity of the power plant—have nothing to worry about.
Still, people are worrying.
Wenonah Hauter is executive director of Food and Water Watch, a nonprofit committed to conserving food and water resources. She said her group is concerned the EPA isn’t taking the threat seriously enough.
“All we hear is there’s no problem. Radionuclides are different. They behave differently; some can bind to rainwater and be dispersed that way. With a continual barrage of radiation from Japan, there just needs to be more testing,” Hauter said. “This is becoming politically motivated because of the development of nuclear industry.”
Ben Monreal, a physicist at UC Santa Barbara, agrees with the EPA’s stance. To educate people about the after-effects of radiation from Japan, he recently gave a lecture titled “Fukushima, Chernobyl, and Beyond: Understanding and Reacting to Radiation.” In that lecture, he stated that the situation shouldn’t be scary and that concern is proportional to how much radiation an individual absorbs.
“So in the case of Fukushima, there’s a tiny level of radiation that’s reached the U.S. and a certain number of people who could’ve been exposed to it, and when you calculate that risk and apply it to everyone, it’s indistinguishable from zero,” Monreal said. “The same seems to be true even in Japan for everyone—except maybe people working at the plant.”
He explained that because there’s already radiation emitted from nature and from things like X-rays and plane trips, humans aren’t as vulnerable to radiation as is often thought.
“It’s not arriving on top of nothing; it’s on top of all the stuff you have been exposed to but haven’t been worried about in your life,” Monreal said.
He explained that natural radiation and manmade radiation affect living cells in the same manner. He also said the timing of the dose is irrelevant—it affects your body the same way, as long as it’s the same amount.
“It doesn’t matter when you get the dose—whether you get the dose all at one time or over your life,” he said. “Health-wise, it’s basically the same.”
However, Monreal said it’s hard to determine the effects of long-term low-level exposure to radiation because there’ve been no real studies on it.
“Most of our understanding is based on the harm it does carry from short doses,” he said.
However, in the short term, Monreal said there’s no need for alarm. He’s conferred with several top scientists, and there seems to be consensus that all is safe. Most of the isotopes now being released don’t travel that far and have a short half-life, so the doses that do appear here are extremely small.
“Even if we were seeing a factor of about 10 percent higher, you shouldn’t ever worry about it,” he said. “I think the government is doing an excellent job monitoring things.”
Dr. Robert Gould of the group Physicians for Social Responsibility said he hasn’t seen any indicators that would raise a red flag for him.
“Levels are still low—elevated above normal, but still below levels where people should be taking potassium iodide,” he said, adding that it’s hard to say what the effects of this low-level exposure will be in the long term.
“We just don’t know,” he admitted.
“The distinction is population versus the individual.”
In other words, it’s hard to pin the
numbers down to an individual’s risk, because all of the research available is based on exposure to populations, and those numbers are subject to manipulation by a variety of factors.
In basic terms, if the level of exposure raises the cancer risk 1 percent higher in a population of 100 people, we’re looking at one additional cancer, he said.
“It’s very difficult to track that back to the individual,” Gould explained. “You really are talking about population exposure.”
As far as someone changing behavior to limit possible increased exposure—such not eating produce because it may have trace amounts of radiation or women who may wonder about breastfeeding because of the possibility of passing on minute amounts of radiation they’ve been exposed to—Gould said any changes need to be evaluated on a case-by-case basis.
“It’s analogous to not being able to get mother’s milk without also finding a host of other carcinogens from the environment that we now know affects mother’s milk,” he said. “But it’s still beneficial. So I don’t know where that tipping point is, where the trade-off is.”
Small doses of radiation continue to be found in milk, rainwater, and drinking water samples, and even in some types of produce around the country, but as those levels drop, there’s still one area that’s raised questions: What about seafood?
Food and Water Watch’s Hauter said seafood is of specific concern because it isn’t being tested and there needs to be tighter restrictions on seafood imports.
“The attitude has been, ‘The solution to pollution is dilution,’” Hauter said.
A joint May 3 press release from the EPA, the Federal Drug Administration, and the National Oceanic and Atmospheric Administration said there’s no planned sampling of U.S.-harvested seafood. The statement indicated that despite the discharge of nuclear waste into the ocean near the Fukushima plant, there’s no concern about radiation in the water or in fish here in the U.S.
“The great quantity of water in the Pacific Ocean rapidly and effectively dilutes radioactive material,” the statement says.
The statement also says current testing of waters 18 miles off the coast of Japan shows that radiation levels have dissipated, reduced to drinking-water standards.
“This means that seafood harvested in areas distant from the damaged reactor is unlikely to be affected. FDA and NOAA do not anticipate contamination of living marine resources in U.S. waters at this time,” the statement says.
Currently, the only fish that’s tested positive for radiation around Japan is the sand lance, which rarely leaves Japanese waters, the statement says.
In Santa Barbara County, though the ocean hugs our coast, there’s no need to worry about exposure of residents, according to Michael Harris, Santa Barbara County Emergency Operations chief—despite the fact that milk in San Luis Obispo County tested positive for radiation.
“The amount of radiation detected was consistent with contamination from Japan. But it never came remotely close to posing a health risk,” Harris said. “From what I understand, you’d have to drink 500 liters of that cow’s milk to sustain enough radiation exposure as you get in one transcontinental air flight.”
Harris said his department heard from government scientists, non-government scientists, scientists from UC Los Angeles, Columbia, and other well-respected institutions—and never heard cause for alarm.
“We, on a local level, never heard anything from any reputable scientific group that ever said this was an issue,” he said.
Harris also said he doesn’t want to think there was any dishonesty in the government reporting. He believes the opposite is actually true, because even though the amounts of radiation were so tiny, the government decided to report them on a regular basis.
But the government can only report or not report on what it knows. And while the winds and tides continue to blow our way, only time will reveal the full findings.
Contact Arts Editor Shelly Cone at scone@santamariasun.com.
This article appears in May 12-19, 2011.