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Anastasia Balezdrova

The raised threat level of nuclear catastrophe at the nuclear power plant in Fukushima to the highest seventh degree under the International Nuclear Event Scale has raised concerns not only in Japan, but also worldwide. Many people wonder how, on the one hand, the company representative could state that the nuclear radiation from Fukushima could exceed the radiation emitted in 1986 and on the other hand, to argue that the accident in Japan is quite different from that at the Chernobyl plant. GRReporter asked the Professor of Nuclear Physics at the Aristotle University of Thessaloniki Konstantinos Papastefanou to answer this and other issues related to the nuclear nightmare lasting in Japan for weeks.
 
Would you explain what the increased threat at the power plant in Fukushima from 5^th to 7^thdegree means in practice?

This is related to the amount of radiation released into the environment. It will become clear how serious the incident is much later, when all leakages are suspended and a final assessment of elements released by the reactors is made.
 
I think that they rushed to raise the level of threat of the accident to 7 in Japan. On the basis of official communications from the responsible people, a serious scientist can not accept today that this degree is real. Because if this is true, how could we assume that the released radiation is equal to only 10% compared to Chernobyl? There is a discrepancy in the information. If the first is true, then the second is wrong.

Could we talk about a new Chernobyl in the case of Fukushima?

The events suggest that it is possible to face such danger, and even a more serious nuclear accident. Furthermore, the information we receive is not sufficient to make a serious assessment.

There was one reactor in Chernobyl, and they are four here. What we know, in fact, is that the reactors are not cooled inside. I do not want to do a prophet, but when I see that Japan is not doing much or what is done yields no results, such a thought is not unusual. For now, however, I do not think it is quite possible.

Which radioactive isotopes were found in the radiation released so far?

Strontium 90 was found in the soil and the plants around the plant, but not in remote areas, although we have no information on the data recorded in them. They do not announce them. At first, they reported for radioactive iodine, then – for radioactive caesium and now – for radioactive strontium. The radioactive products of nuclear fission are about 25 in number. It is impossible not to be released the first time. There is no way of releasing one radioactive isotope and to stop the others. It is clear that they do not report these things not to panic the local population and the rest of the world.

Has the radiation reached Europe?

The radiation has reached everywhere. Isotopes of xenon have been found along the west coast of the USA. Various isotopes have been detected along the northeastern coast too. Iodine 131 and caesium 134 and 137 have been found in all European countries. Consequently, at least the northern hemisphere, where the air masses move in one direction, is completely affected by the nuclear radiation released by Fukushima.

Are the quantities dangerous, however?

The quantities are high especially in Japan, around Fukushima and the adjacent areas. Then, the clouds formed by the continuous leakage of radiation move and the air masses carry them to very large distances. Japan is in the middle of a very large ocean. So, there are no obstacles and the cloud that is over it could easily move. Apparently, there are draughts from the south to the north. This explains the fact that the radiation reached the North Pole very quickly. And let us not forget that, the movement of water in the Pacific Ocean is towards the North Pole. Thus, when the cloud continued to move it ended up over the Atlantic Ocean, having passed over Iceland. It has begun to dissipate there, because when the clouds move long distances they dissipate at a certain point. From that point on, the radiation has begun to spread by the method of diffusion both to the east and the west, to the USA and Europe and gradually onwards.

This means that it was not necessary a cloud to reach us. The radiation arrived through diffusion. It can reach many places in this way, but in particularly low quantity. This explains the fact that the level of radiation in Europe is low and, in fact, it is about a million times lower than the radiation in the area of the ​​plant.

Here is the difference compared with the accident at the Chernobyl plant, when the radiation over Greece was very high, at least a million times higher than that currently in Fukushima. This means that the situation there is serious, but here it is not. However, we should clarify that we are talking on the base of the amounts of radiation measured across Europe.

If, however, the technicians completely lose control and the release of radiation continues or if a reactor explodes and large quantities of radiation are released into the atmosphere, this would mean that the quantities that would move would be huge. But I personally do not believe that such a high radiation could reach us, compared to that which had come here after the explosion of the reactor in Chernobyl. I think this is very difficult, if not impossible to happen. But much higher amounts of radiation could reach us than those we have now.