By JR on Friday, November 18, 2011
Radiation levels at Fukushima are negligible
The fallout from the radiation leak at the Fukushima Daiichi nuclear reactor in Japan may be less severe than predicted.
Radiology researcher Ikuo Kashiwakura of Hirosaki University, Japan, and colleagues responded immediately to the disaster, travelling south to Fukushima prefecture to measure radiation levels in more than 5000 people there between 15 March and 20 June.
They found just 10 people with unusually high levels of radiation, but those levels were still below the threshold at which acute radiation syndrome sets in and destroys the gastrointestinal tract. Geiger-counter readings categorised all others in the area at a "no contamination level".
How did the population of Fukushima prefecture dodge the radioactivity? Gerry Thomas at Imperial College London, director of the Chernobyl Tissue Bank, says the answer is simple. "Not an awful lot [of radioactive material] got out of the plant – it was not Chernobyl." The Chernobyl nuclear disaster released 10 times as much radiation as Fukushima Daiichi.
Thomas says the quick and thorough response by the Japanese government limited radioactive exposure among the population. On 12 March, the same day as the first explosion at Fukushima Daiichi, the government ordered the evacuation of residents within 20 kilometres, and asked various institutions to begin monitoring contamination levels.
"They had no faxes, no emails, nothing was working," says Thomas, adding that other countries might not have coped as well with a combined earthquake, tsunami and nuclear plant malfunction. "Given the circumstances, they did phenomenally."