Abstract
Tritium is a naturally occurring radionuclide. Much tritium was released to the environment by nuclear testing in 1960s, the effect is still remained in deep seawater and groundwater, but not in rain. Local tritium source is the nuclear installations, which increase environmental level locally. Nuclear fusion facility will use a huge amount of tritium, and then environmental evaluation for fusion reactor is important. An environmental tritium model based on knowledge on environmental behavior of natural, bomb and nuclear power plant's tritium is necessary. Tritium level in various kinds of environmental materials has been analyzed. I will talk recent environmental tritium levels and transfer and transformation of tritium in the environment.
