A worldwide network of sensors found that levels of radioactive caesium 137 released from the damaged nuclear plant were significantly higher than anticipated, according to the Norwegian Institute for Air Research study.
The Japanese government estimated that 15,000 terabecquerels of caesium were released after the plant was damaged, while the new study put the figure at 36,000 terabecquerels – 40 per cent of the total released from Chernobyl.
Andreas Stohl, author of the preliminary study, focused on the emission of caesium 137, a slow decaying element which can last for 30 years in the environment and release cancer-causing radiation.
The discrepancy in Fukushima levels was attributed to the possibility that data recordings in Japan at the time would not have taken into account the emissions which were blown directly out to sea.
Around 20 per cent of the caesium settled on land in Japan, while the remainder is believed to have fallen into the Pacific Ocean, with around two per cent ending up on land outside the country.
Japan’s Nuclear Industrial Safe Agency, the body overseeing radioation levels, said it was unable to comment as it had not reviewed…