By Tanya Silverman
The Fukushima Daiichi plant in Japan. Photo courtesy of Wikimedia Commons.
In March 2011, an earthquake triggered a tsunami that hit the Fukushima Daiichi plant in Japan, causing a nuclear meltdown. Though the waves have subsided, the resulting complications remain ongoing after nearly two and a half years.
Contaminated water and pollutants have been released from the plant ever since the beginning of the incident, and continue to flow into the groundwater and Pacific Ocean – a Japanese government official estimated that about 330 tons of water is being leaked into the ocean daily.
An incident occurred last month where 300 tons of contaminated water had leaked from a storage tank at Fukushima, which has caused widespread alarm. The Tokyo Electric Power Company (TEPCO), the company that operates the Fukushima plant, has been criticized for their inability to contain the large amounts of contaminated water (containing radioactive isotopes like caesium-137 and strontium-90) from leaking into the environment. The Fukushima plant is still considered unstable, and the release of more contaminated water is seen as inevitable.
Seafood has been a subject of concern. Fish around Fukushima have been tested and determined as unsafe for human consumption, especially bottom feeders. Fisheries in the proximity to Fukushima have been closed, and will remain so indefinitely.
Ken Buesseler, Senior Scientist at Woods Hole Oceanographic Institute, has examined thousands of ocean fish samples in the waters around Fukushima to determine their safety. Buesseler, who began his career in oceanography by surveying the effects of radionuclides in the Black Sea from the Chernobyl nuclear accident, has been researching radiation effects from Fukushima since mid-2011. In June of that year, he organized the first Fukushima international research cruise in the Pacific Ocean.
Today, Buesseler has grown into a significant scientific authority on Fukushima ocean radiation.
Though he has traveled to Japan several times to study contamination, many people are concerned with radiation affecting the West Coast of Buesseler’s home country, the United States.
Regarding radioactive contaminants in the US, Buesseler considers the radiation effects to be too diluted by the time they travel across the Pacific to pose any serious threat:
“At the [radioactive isotope] levels we’ve seen on the US coast, we don’t see significant health problems.”
Buesseler gives some perspective on the different radioactive isotopes being released by the contaminated water. He compares caesium-137 to a “salt” that passes “in and out of fish when they ingest and then excrete.” It passes through human bodies quickly. He adds that the amount of the pollutant detected in fish on the West Coast is much less than the amount of polonium-210, a naturally occurring radioactive isotope caused by the weathering of rocks, which is “a more dangerous type of isotope, because of its decay, than ceasium.”
Though the level of caesium in the Fukushima waters has been decreasing, levels of strontium-90 are going up. Strontium-90 is considered more of a risk than caesium, in that it “replaces calcium in bones” and if humans eat fish with this pollutant, it can remain in human bodies for years.
While Buesseler may not see strontium-90 as a risk for the US Pacific Coast, he does predict a prolonged closing of the Japanese fisheries because of consequent contamination. He also calls for further investigations into the level of strontium presence in the Fukushima water.
Another American scientist who has been studying the effect of radiation around Fukushima is Tim Mousseau, a biology professor at the University of South Carolina. Mousseau has also worked in Chernobyl, conducting research on subjects like radiation-induced bird mutations; he has since applied his expertise to Japan.
“Everyone should be concerned that this kind of event can happen anywhere, and the fact that it has measurable reaches, even across the Pacific Ocean, suggests that these events have worldwide impacts, potentially,” states Mousseau on Fukushima.
This biologist considers the threat of any “large-scale health impacts of these contaminants in North America” as unlikely, because their concentration will be “very, very low by the time they reach the coast.” However, he does believe that the Fukushima radiation is bound to affect some people: since these contaminants are so widely dispersed, it will mean that a great deal of humans will be exposed them, therefore, the dispersion of pollutants poses risks of developing diseases like cancer.
Mousseau states that the causes for such diseases tend to be complex, though, so it would be difficult to determine if the Fukushima accident would automatically lead to any kind of pestilence — other factors that contribute to developing a disease such as cancer include environment, diet, exercise and genetics, which makes it difficult to “unravel exactly what the source” is.
A third American, Taylor Wilson, the teenage nuclear scientist, admits that he was too young to conduct any studies on radiation in Chernobyl, but took advantage of the opportunity when Fukushima occurred. Setting up a monitoring system for fission/activation products transported by wind, Wilson tested samples of milk, water, air, and spinach for isoptopes like caesium and iodine in Nevada.
From what he gathered, these radioactive isotopes “were never at the level where they would cause any kind of harm.”
“They were about a thousandth of the level of a dose of radiation that you would accumulate from a transcontinental flight, for example,” Wilson tells BTR. Wilson was only able to detect radiation for a brief time after the accident.
“In about a month after [the Fukushima accident], the levels went below my level of detection, which was very, very low. So there was never, of course, a danger to the United States, the western seaboard or the west coast – but it was interesting to know you could see those levels,” he says.
Though he concluded no airborne threats are making their way to the US from Fukushima, this 19-year-old nuclear scientist acknowledges that the current issues in Japan with the contaminated water are something that “TEPCO really needs to get a handle on,” and if they cannot, “other parties need to step in.”
Ken Buesseler has told National Geographic that he is becoming “less confident” in TEPCO’s ability to handle the problem.
Japan has just pledged 47 billion yen to curtail leaks from Fukushima, and there has been a proposition to build an “ice wall” to stop leaks. Whether TEPCO, or another organization, takes the responsibility for this problem, a great deal of resources will need to be implemented to ensure immediate safety, monitor ongoing security and investigate long-term effects.