After the reactor accidents in Fukushima as a result of earthquakes and tsunami, there is uncertainty about the concrete effects of the disaster in Japan. In conversation with Dr. Thomas Jung, radiation biologist, professor and director of the Federal Office for Radiation Protection (Department of Radiation Effects and Radiation Risk), we get to the bottom of fundamental questions on consequences for health and nutrition.
Is there any risk of radioactivity for us in Germany after the reactor accidents in Japan?
Jung : In Germany, the radiation exposure will not be so high that it could be dangerous to health. In about two weeks, depending on the weather conditions, we will be able to measure a minimal increase in general radioactivity. This will not be harmful to health. In Germany, an annual radiation exposure of two to three millisieverts (0.002 Sievert), which generally consists of natural radiation sources, is usual.
Due to the reactor accident in Japan, this radiation exposure will not increase significantly: Currently, we expect an additional burden at most in the range of microsieverts (1 microsievert = 0.000001 Sievert) in Germany - based on the radiation dose for the entire coming year. By comparison, for example, a long-haul flight over the North Atlantic route has a load of about 50 microsieverts.
Would it then be excessive to take iodine tablets for precaution?
Jung : It would not only be exaggerated, but even contraindicated in the current and expected situation in Germany to take iodine tablets to protect against radioactive iodine. The high doses of iodine necessary for effective iodine blockade of the thyroid gland (2 x 65 mg potassium iodide contraceptive pills for adolescents aged 13 years and over the age of 45 years, instead of the recommended daily dose of 0.2 mg iodine) pose a high risk of a metabolic imbalance.
The normal human organism and especially that of an already overactive thyroid are overstimulated by the short term high amount of iodine. This can provoke life-threatening circulatory disorders. An ingestion is therefore only to be carried out by official instructions and if possible under medical supervision.
Do you assume that many people are actually taking iodine prematurely out of fear?
Jung : Despite the risk of uncontrolled intake of iodine tablets, it is reported that European pharmacies are buying up iodine tablets. At present, we should be more afraid of incidents in Germany because of side effects of drugs due to exaggerated precaution than to radioactivity. From our side it is therefore strongly advised not to take iodine tablets independently. When traveling to Japan, it is important to consult a doctor and not to treat yourself with iodine.
How would iodine prophylaxis work in an emergency?
Jung : For iodine prophylaxis, taking just a few hours before the arrival of the radioactive cloud is sufficient. However, we currently do not expect such a cloud. We also do not expect that in countries like Thailand or Vietnam, several hundred kilometers away from Japan, there will still be a high dose of radioactivity that would justify the intake of iodine tablets. Due to the filtering effect of the atmosphere, the radioactive material is greatly diluted.
In the actual emergency, which currently prevails in Europe and is not expected, those affected would need to take two emergency tablets of 65mg potassium iodine. In an emergency, the authority would call for this.
Which foods could be contaminated by radioactivity in Japan?
Jung : The food that has been found on supermarkets' shelves so far has not gotten any of the radioactivity since it was imported before the accident. So you do not have to worry about that. In addition, there is currently winter in Japan, so that there are hardly any crops such as rice or fruit grown anyway. The contaminated area in Japan around the accidental nuclear power plants is currently so much affected by the natural disaster, so that from there it is not expected for the first time, that exports of food done.
Fish and seafood are the foods that could potentially be at risk. However, as new guidelines and limits for the most accurate food controls have been developed and implemented in the context of the Chernobyl disaster, we can now draw on these experiences and standards.
All foods that could be dangerous are carefully controlled before import. For example, fish are broken down into their composition using specific radiochemical methods and measuring instruments to see which radioactive substances may be contained.
Do pregnant women have to pay special attention?
Jung : Even today, some mushrooms, such as truffles, are radioactively contaminated by the reactor accident in Chernobyl. As well as meat of wild boar. However, these products are carefully controlled before they are put on the market so they should be safe.
More dangerous are self-collected mushrooms or wild boar meat that has not been tested for radioactivity - pregnant women are best off doing so. In Japan, contamination with radioactive material will have similar consequences - we need to see if the local fungi also tend to enrich the radioactive cesium.
Where else can you travel without fear of radioactivity?
Jung: I would only advise against travel to Greater Tokyo and the disaster area. The people there are affected by a severe natural disaster and the area is therefore currently not suitable for travel dar. In other countries such as the Pacific coast of South America or in general to Southeast Asia, however, one can travel easily, without being afraid of radiation.
How can you detect radioactive radiation?
Jung: Man has no sense organs for radioactivity. That's just the scary thing about her. The radiation can only be detected with the help of measuring instruments. Only when exposed to large amounts of radiation, such as in 1986, the people who were directly affected by the Chernobyl disaster on site, can develop an acute radiation syndrome, with nausea, vomiting and bloody diarrhea, which can lead to death,
What would one do if such a reactor accident happened in Europe?
Jung: In principle, what's done in Japan is the same thing we would do in Europe. With the difference that the citizens must be informed comprehensively and far more about the situation. When high levels of radiation exposure are expected, rapid evacuation of the area within a radius of 20 kilometers around the power plant and more is important.
However, exactly where to evacuate depends on the regional situation. Later, perhaps even further - one must always consider whether the dangers of an evacuation are higher than those caused by the radioactivity at the respective distance. In addition, one must decide quickly whether and in which areas iodine tablets should be distributed.
In general, in a radioactive emergency, people should first stay in their homes because there is less exposure to radiation than outside. Evacuation and intake of iodine tablets should only be carried out on the instructions of the authorities and not independently. The discipline of the Japanese in the evacuation, despite the tremendous burden of the natural and the threatened nuclear disaster has certainly helped to avoid further victims.
The interview was led by dr. med. Julia peoples.