The U.N. nuclear agency has said that seven European countries are reporting low but unusual levels of radiation for a second week.

An International Atomic Energy Agency (IAEA) statement said “the continued presence of trace levels of iodine-131 in the atmosphere” are being reported by the Czech Republic, Austria, Slovakia, Germany, Sweden, France and Poland.

The statement on Wednesday said the agency is trying to determine the cause of the radiation, which it described as “extremely low.” It said that breathing in the isotope for a whole year would have far less effect than that posed by normal radiation that is always present. The IAEA first reported the radiation on Friday.

Not because of Fukushima

It said it had received information first from the Czech Republic's State Office for Nuclear Safety. The current trace levels do not represent a health risk and are not caused by the accident in March at the Fukushima Daiichi nuclear plant in Japan, according to the agency. Iodine-131 is a short-lived radio-isotope with a radioactive decay half-life of about eight days.

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