Base Information Q&A SiteJAEA

Case of Juman Mountain Forest Fire in 2017


Cs released to the environment by the forest fire?

Release of radioactive material during Juman-Mtn fire event was limited, and even if existed, the concentration in air is significantly smaller than the usual airborne dust concentration.

  • Radio-cesium concentration and levoglucosan (plant combustion index) concentration in the airborne dust were analyzed.
  • Levoglucosan concentration indicated high value during the fire event, but low after the event, and it reflected the effect of event.
  • On the other hand, definite correlation between radio-cesium concentration and levoglucosan was not observed (highest radio-cesium concentration was found after the fire event)
    ⇒ Origin of radio-cesium in airborne dust is considered to be other item than the fire.

Fig.1 Cs concentration (upper fig.) and levoglucosan concentration (lower fig.) during and after the fire event