Tritium exists in environmental samples in three forms: (i) Tissue Free Water Tritium (TFWT) and associated with the organic matter (OBT) under two forms; (ii) bound to oxygen and nitrogen atoms into the material (EOBT); (iii) bound to carbon atoms into the material (NEOBT). The developed analytical procedure allows obtaining accurate and reproducible information for the various tritium fraction determinations.

Aiming to follow the distribution and the integration of NE-OBT in the vicinity of a nuclear research centre down to environmental level the analytical procedure was optimized to reduce possible contamination during critical stages such as the E-OBT elimination. Therefore, a new process using steam was designed and investigated leading to promising results.

A broad study was initiated to study potential impact of tritium on tree leaves sampled in the vicinity of a nuclear research centre within a radius of about 20 km. Moreover both plane tree and oak leaves have been sampled to establish the NE-OBT mapping. Therefore, for several locations they were sampled twofold for comparison. Appropriate statistical tests allow assessing that the type of tree does not influence the NE-OBT integration in our experimental conditions.