Determination of low ~(137)Cs concentration in the atmosphere due to Chernobyl contaminated forest-wood burning

摘要

The determination procedure of low Cs-137 concentrations in air using gamma-spectrometry is essential wherever the net counts are smaller than the background of the spectrum. Such measurements have performed in April 2020 during the Chernobyl wildfires period. A significant event recorded in Thessaloniki's atmosphere during April 12, 2020, with 25.7 +/- 0.7 mu Bq m(-3) of Cs-137, was measured. Besides, a minor incident with a lower Cs-137 concentration of 9.6 +/- 0.8 mu Bq m(-3) has occurred on April 21, 2020. The above results resemble to a previous one noticed during winter 2013, when signals up to 12.1 +/- 0.8 mu Bq m(-3) of Cs-137 detected in the atmosphere, due to extensive use of Cs-137 contaminated wood for residential heating. The results obtained demonstrate that no radiation hazard rose for the general public due to inhalation of the Cs-137 in the air of Thessaloniki, Greece. Moreover, the residence time of the aerosol-bound Cs-137 has estimated. The data presented are useful for basic simulation-inputs and comparison with global atmospheric models, which also discussed after comparison with the back trajectories predicted by the NOAA-HYSPLIT model.