RADIOACTIVE contamination has reached Ireland from the stricken Japanese nuclear power plants at Fukushima. Levels are so low that they pose no health risk, according to the Radiological Protection Institute of Ireland who measured the radiation.
A large air sample was taken over the weekend in Dublin and was analysed for 24 hours. The institute confirmed yesterday that the sample had low levels of radioactivity.
“This is the first sample to show Fukushima radiation,” said Dr Ciara McMahon, the institute’s director of environmental surveillance and assessment.
“There are no health risks. The only reason we were able to detect it is we have taken such a large sample of air,” she said yesterday.
The institute gets regular updates on the Fukushima power plant via the International Atomic Energy Agency, of which we are a member.
However, the institute also uses a network of 14 radiation recording stations and 13 air sampling stations, including one high-volume air sampling station to provide early warning of any nuclear contamination after an accident.
Radioactivity levels are measured in becquerels (or fractions of a becquerel) per cubic metre of air. The air samples taken over the weekend showed 20 millionths of a becquerel, Dr McMahon said.
By comparison, the levels reaching Ireland from the Chernobyl disaster of April 1986 peaked at 195,000 millionths of a becquerel, she said.
Human doses of radiation are measured in sieverts (or fractions of a sievert). A typical Irish person receives three or four thousandths of a sievert from natural sources every year.
The radiation reaching us from Fukushima, if averaged out over a year, would raise this exposure by 0.000005 thousandths of a sievert, Dr McMahon said. Radiation levels are so low, however, that they vary up and down and can reach zero depending on wind direction, she added.
The institute was keeping a close watch on radiation levels in Japan. “The area we are looking at most closely is Tokyo so that we are in a position to give advice to the Department of Foreign Affairs on risks to Irish people living in Japan,” she said.
Levels in Tokyo have been low other than when they increased for a short time in the city’s water supply. “Our advice to people is to follow local advice [in Japan] because they will have the most up-to-date information,” Dr McMahon added.