Levels of radioactive materials in the fallout obtained everyday, 2026 Fiscal year

The sampling and measurement are conducted at the Tokyo Metropolitan Institute of Public Health (Hyakunin-cho, Shinjuku-ku, Tokyo)

Sampling date 131I
Bq/kg
Radioactive Cesium
134Cs
Bq/kg
137Cs
Bq/kg
9:30, Thu., 02 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
9:30, Wed., 01 Apr. - 9:30 the following day ND(not detectable) ND(not detectable) ND(not detectable)
  • Samples are collected and analyzed everyday using a germanium semiconductor detector.
  • It is known that rainfall may increase values.
  • The number of significant digits of values is set as 2 in order to be consistent with that of the Japanese government.
  • Please see here about the principle behind “ND (Not Detectable)”.
  • A unit of values is Bq/m2, identical to MBq/km2.

Please see the pages for each year for data from previous surveys