*Naofumi Akata1, Masahiro Tanaka2, Shigekazu Hirao3, Toshiya Tamari4, Hideki Kakiuchi5, Shinji Sugihara6, Haruka Kuwata1, Hirofumi Tazoe1
(1.Hirosaki University, 2.National Instutute for Fusion Science, 3.Fukushima University, 4.Kyushu Environmental Evaluation Association, 5.Institute for Environmental Sciences, 6.Kyushu University)
Keywords:tritium, atmospheric environment
Tritium (3H; T1/2 = 12.3 y) is the radioisotope of hydrogen and it decays to 3He; the main sources of environmental tritium are natural, although there are some artificial sources. The 99% of environmental tritium exists in water vapor, rainwater, landwater and seawater as a chemical form of HTO , and moves on the earth surface according to water cycle. It is common to use a low background liquid scintillation counter for tritium measurement in general environment. On the other hand, atmospheric tritium have three chemical form which are water vapor (HTO), hydrogen (HT) and hydrocarbons (mainly CH3T), they are separately collected as water after oxidation for measurement.
This presentation reports the measurement technique for tritium in the atmospheric environment.