After the reactor accidents in Fukushima as a result of the earthquake 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 for Radiation Effects and Radiation Risk), we get to the bottom of fundamental questions about the consequences for health and nutrition.
Is there a 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 pose a health risk. In about two weeks, depending on the weather, you will be able to measure a minimal increase in general radioactivity. However, this will not be harmful to health. In Germany, an annual radiation exposure of two to three millisieverts (0.002 Sieverts), which is generally caused by natural radiation sources, is common.
This radiation exposure will not increase significantly as a result of the reactor accident in Japan: At the moment, we are anticipating an additional exposure at most in the range of fewer microsieverts (1 microsievert = 0.000001 Sievert) in Germany – based on the radiation dose for the entire coming year. In comparison, a long-haul flight over the North Atlantic route, for example, has a load of around 50 microsieverts.
Would it then be an exaggeration to take iodine tablets as a preventive measure?
Jung : It would not only be an exaggeration, but also contraindicated in the current and expected situation in Germany, to take iodine tablets to protect yourself from radioactive iodine . The high doses of iodine necessary for effective iodine blockade of the thyroid gland (2 x 65 mg potassium iodide emergency tablets for adolescents from 13 years of age and adults up to 45 years of age, instead of the recommended daily dose of 0.2 mg iodine) harbor the high risk of metabolic derangement.
The normal human organism and especially that of an already overactive thyroid are over-stimulated by the short-term high amount of iodine. This can provoke life-threatening circulatory disorders. It is therefore only to be taken if instructed by the authorities and if possible under medical supervision.
Do you assume that many people actually take iodine prematurely out of fear?
Jung : Despite the risk of uncontrolled intake of iodine tablets, there are reports of iodine tablets being bought up in pharmacies across Europe. In Germany we should be more afraid of incidents due to side effects of medication due to excessive preventive care than of radioactivity. We strongly advise against taking iodine tablets on your own. Even when traveling abroad to Japan, it is important to consult a doctor and not simply treat yourself with iodine.
How would iodine prophylaxis work in an emergency?
Jung : For iodine prophylaxis, it is enough to take a few hours before the radioactive cloud arrives. However, we are currently not expecting such a cloud. We also do not assume that in countries like Thailand or Vietnam, which are several 100 kilometers away from Japan, there will still be a high dose of radioactivity that would justify taking iodine tablets. The radioactive material is heavily diluted by the filtering effect of the atmosphere.
In an actual emergency, which currently does not exist in Europe and is also not expected, those affected would have to take two emergency tablets of 65 mg potassium iodine each. The authority would request this in an emergency
Which foods could be contaminated by radioactivity in Japan?
Jung : The food that has been on the supermarket shelves up to now has not yet received any of the radioactivity because it was imported before the accident. So here you don’t have to worry. In addition, it is currently winter in Japan, so that hardly any grain such as rice or fruit is grown there anyway . The polluted area in Japan around the failed nuclear power plants is currently so badly affected by the natural disaster that food exports cannot be expected from there for the time being.
Fish and seafood are the foods that could be potentially at risk. However, since new guidelines and limit values for the most precise food controls were drawn up and implemented in the context of the Chernobyl disaster, we can now fall back on these experiences and standards.
All food that could be dangerous is carefully checked before import. Fish, for example, are broken down into their composition using special radiochemical processes and measuring devices in order to see which radioactive substances they may contain.
Do pregnant women have to pay attention to anything?
Jung : Even today, some mushrooms, such as truffles, are radioactively contaminated by the reactor accident in Chernobyl. Also meat from wild boar. However, these products are carefully checked before they are placed on the market, so that they should not pose any danger.
Mushrooms you have picked yourself or meat from wild boar that has not been tested for radioactivity are more dangerous – pregnant women should best avoid them. In Japan, contamination with radioactive material will have similar consequences – we have to see whether the fungi there also tend to accumulate the radioactive cesium.
Where else can you travel without being afraid of radioactivity?
Jung: I would only advise against traveling to the Tokyo area and the disaster area. The people there are affected by a serious natural disaster and the area is therefore currently not an area suitable for travel. In other countries, such as the Pacific coast of South America or in general to Southeast Asia, you can travel without any problems without fear of radiation.