Estimation of radionuclide emission during the March 15, 2011 accident at the Fukushima-1 NPP (Atomic Energy Journal Volume 112, Issue 3), July 2012:
“According to estimates made by the present authors, the following radionuclides entered the atmosphere on March 15, 2011 (PBq): ~400 iodine, ~100 cesium, and ~400 inert gases.”
Wikipedia’s entry on Chernobyl states, “20 to 40% of all core caesium-137 was released, 85 PBq in all.” The source cited is Chernobyl: Assessment of Radiological and Health Impact -Nuclear Energy Agency (NEA)
The same source gives another amount for the Chernobyl release that is considerably less, “However, more deposition data were available when, in their 1988 Report, the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) gave release figures based not only on the Soviet data, but also on worldwide deposition. The total 137Cs release was estimated to be 70 petabecquerels (PBq)” -Nuclear Energy Agency’s 2002 assessment of the Chernobyl disaster
According to the Committee on an Assessment of CDC Radiation Studies, National Research Council: “35 PBq of Cs-134 and 70 PBq of Cs-137 were released into the atmosphere” at Chernobyl.
Fukushima’s total cesium releases are considerably higher than the 100 PBq stated in the July 2012 study, as that included only atmospheric releases and none of the plant’s record discharges into the ocean (up to 47 quadrillion becquerels)… and it is only based on the amount from a single day.
For more on Fukushima’s ocean releases see: Nuclear Engineer: Estimated 276 quadrillion Bq of Cs-137 entered Fukushima basements -- Triple Chernobyl total release -- A portion "has already made its way to aquifer, whence it can easily flow into sea"
Published: August 29th, 2013 at 9:56 am ET