Ken Buesseler Fukushimako itsas isurien ikertzailea

“Scientists have the responsibility and I hope some influence”

2013/10/31 Galarraga Aiestaran, Ana - Elhuyar Zientzia Iturria: Elhuyar aldizkaria

The researcher of the Institute of Oceanography, Wood Hoods, Ken Buesseler, has worked from the beginning in the study of radioactivity fused from the Fukushima nuclear power plant, initially with data provided by the company TEPCO and subsequently with samples in situ. In their view, the official Japanese institutions have not done enough to analyze and guide the situation, is why it demands the need to have the participation of independent experts.

(updated to 1 December 2013)

Ken Buesseler, researcher at the Wood Hoods Oceanography Institute (WHOI). Ed. Tom Kleindinst/WHOI
Compared to the Chernobyl event, Fukushima is reaching the sea with more radioactive isotopes. To what extent do they arrive and what effects do they have?

Total emissions may be lower than in Fukushiman Txernobyl, but being on the edge of the ocean, and since a large amount of water used for cooling, either directly or underground, goes to the sea, dumping into the ocean is between 2 and 5 times higher than in Chernobyl.

Initially, in 2011, ocean concentrations, in situ, were very high. Although they then went down, after a few months they went up: they were an early sign of those continuous spills that we are still listening to.

In fact, the impact of radioactive isotopes is more worrying on earth than on the sea, since they can directly affect humans, since they are immediately diluted in the ocean and mixed with streams of water away from the coast. However, the accumulation of isotopes such as cession in fish is a matter of human concern. This has meant the closure of important coastal caladero, which has meant not only a loss of millions of dollars, but also the loss of an important food from the local and cultural point of view.

How are you investigating the evolution of radioactive isotopes at sea? What techniques do you use?

With the oceanographic boat we took samples and took them to the laboratory. Then we separated the radioactive isotopes of Fukushima from the natives and analyzed them. For example, one of the most commonly used methods for the study of cesium isotopes is the measure of gamma decay.

What are the main conclusions of the investigations carried out so far?

Follow-up of radioactive isotopes is not enough. We must complement it with the knowledge of oceanographers to know, for example, how marine currents influence the mixture of particles and why the concentration of cessions is a thousand times greater in a given place than in another, or to understand how it accumulates in the trophic chain, or why a small part of the cession is directed to the seabed and for how long it remains there.

Ken Buesseler in front of the Fukushima nuclear power plant. Ed. Ken Buesseler, abandoned by Woods Hole Oceanographic Institution.
What do you think Tepco and the Japanese government can do to improve the situation? Do you think someone should participate?

Without a doubt, yes: Japan should invite international experts to investigate the consequences of the ocean. Until recently they have not requested aid for cleaning...

The participation of government agencies is not enough. The impartial analysis of the conclusions requires experts from countries like Japan, the United States or Europe independent of nuclear energy organizations and their sponsors.

We have to do more than what has been done so far to present the results to the public that is becoming increasingly skeptical.

Who is the responsibility of researchers like you? Can they or should they influence some specific aspect? To what extent?

Yes, scientists have the responsibility and I hope it has some influence. I have received many praise for our work, such as the special issue of Oceanus magazine and a FAQ page on the whoi web, in addition to articles published in scientific journals.

Which scenario foresees in the short or medium term?

My main concern is to stop the discharges that leave the tanks and the building, as well as the decontamination systems are efficient. This should be a priority, while ensuring the safety of the fuel used in the exterior ponds of the reactors. Unfortunately, there is currently more radioactivity in tanks and fuel rods than in 2011, so any new accident, such as an earthquake, can cause more damage than the initial incident.

Ken Buesseler
Degree in Biochemistry and Cell Biology and Doctor in Marine Chemistry. He is currently a researcher at the Wood Hoods Oceanography Institute (WHOI) and specializes in radioactive isotope research on both land and sea. Before investigating the radioactivity of the waters of the Fukushima area, he has investigated the remains of nuclear tests during the Cold War in the Atlantic and the Black Sea, the radioactive isotopes fused from Chernobyl.
Some significant parts taken from the special issue of the magazine "Fukushima and Ocean" Oceanus
This special issue was published in the spring of 2013 and on the cover, together with the title, the following question is raised: "What have we learned from the dumping of radioactive pollutants into the ocean without precedent? ".
Take samples of coastal water from the central Fukushima. Ed. Ken Buesseler, abandoned by Woods Hole Oceanographic Institution.
The journal consists of six articles: The triple Japanese disaster (earthquake, tsunami and caused by the nuclear power plant); Radioactive isotopes in the ocean; How the seafaring is affecting Fukushima; Fish and seafood food security and policy; Health risks and communicative disaster. Of these, especially in the first three appear the statements of Buesseler.
In fact, in his first article, Buesseler recalls that 80% of the radioactivity poured from the central Daiichi went to the sea and not to the land, so Buesseler considers that it could be "worse" in this regard.
However, the radioactive spill was the largest ever recorded in the ocean. Initially, Buesseler analyzed the data provided by the company TEPCO, owner of the nuclear power plant. He says he "spent a lot of time to begin to clarify the measure of pollution." Finally, on 6 April 2011 [2011] it was reported that the concentration of cesium-137 in the outer waters of the plant was 60 million Bq/m3, i.e., "extremely high".
"Then we started to worry," Buesseler acknowledges. And he began to try to go there. After a few weeks, he managed to gather a group of scientists and obtain the necessary grant, granting in June the authorization to take water samples. When they left, the concentration of cesium was much lower due to the marine current called Kuroshio: "Despite being higher than normal, it was below the level of risk for animals or people". Given the importance of fish in the Japanese diet, it was good news.
However, in his article published in the journal Science in October 2012, he showed that in many types of fish the concentrations of cesium were not decreasing. And many questions remained unanswered. However, according to Buesseler, "the goal is not to create alarm or blame anyone, but to conduct a scientific research study to see what we know and what not of the pollutants emitted in Fukushima, how they evolve at sea and what consequences they can have on marine ecosystems and people's health."
Thus, the following article in the journal Oceanus shows information about radioactive marine isotopes: what is there, how much and how long. Buesseler clarifies that in the 2011 catastrophe mainly iodine 131, cesium 134 and cesium 137 were emitted: "All of them cause health damage, but as iodine 131 has only 8 days of life, it quickly disappears from the middle. On the contrary, the other two have an average life of 2 and 30 years, respectively, so years and decades will go away."
In one of the shipments carried out from the coast at the height of Fukushima in a range of 30 to 600 km, he stated that "the highest levels of radioactivity were near the coast", but not to the height of Fukushima, but to the south, near the Ibaraki prefecture. This showed them the importance of currents. Therefore, a posteriori a great attention has been paid to this factor, creating a model of ocean currents.
Thanks to the model, the trajectory of the isotopes is being understood, although, according to Buesseler, they continue to have "significant lagoons", especially in the follow-up of the isotopes that sink and accumulate in the fish. In addition, they have been separated from natural radioactive isotopes and the radioactivity chain has been studied in each type of radiation. In short, according to Buesseler, "we live surrounded by radioactivities; the risk is in doses."
Finally, in the third article, the influence of Fukushima's radiation on live sailors is reflected. Analyzing the trophic chain, they have been found mainly in plankton and fish isotope samples of cesium 134 and 137, but not iodine 131. And, fortunately, the cession is very little concentrated in the trophic chain. In this sense, the data are quite relaxing.
However, researchers have another concern: the level of radioactivity does not decrease over time. According to them, one of the sources can be the radioactivity that accumulates in the sediments of the seabed, "and can last decades."
In the last three articles, Buessele's protagonism is minor, but among all offer a complete overview of the effects of the Fukushima disaster at sea.

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