Measurement of organically bound tritium in biological samples

We present a sensitive method for low level non-exchangeable OBT (Organically Bound Tritium) determination by a combination of a suitable sample treatment, a combustion apparatus for large sized samples and low background liquid scintillation spectrometry, along with a methodology that eliminates any possibility of tritium exchange between samples and of extraneous contaminations. That tritium measurement supplies basic information on previous activities at one specific place. (authors)