From Reuters -
The release of two types of radioactive particles in the first 3-4 days of Japan‘s nuclear crisis is estimated to have reached 20-50 percent of the amounts from Chernobyl in 10 days, an Austrian expert said Wednesday.
That’s not encouraging. The numbers 20 and 50 percent are not as wide a variance as might be thought. They are referring to two different kinds of radiation.
The Austrian institute’s Dr Gerhard Wotawa stressed the two isotopes from Fukushima he had sought to estimate — iodine-131 and caesium-137 — normally make up only one tenth of total radiation.
Based on measurements made at monitoring stations in Japan and the United States, Wotawa said the iodine released from Fukushima in the first three-four days was about 20 percent of that released from Chernobyl during a ten-day period.
For Caesium-137, the figure could amount to some 50 percent.