Tritium in [18O]water containing [18F]fluoride for [18F]FDG synthesis

The presence of tritium in enriched [18O]water irradiated with 9.6 MeV protons used to produce [18F]fluoride by the 18O(p, n)18F reaction was inferred from the cross sections and threshold energies of the 18O(p, t)16O reaction, and the existence of tritium was confirmed experimentally. Tritium was also detected in both [18O]water recovered for recycling and waste acetonitrile solutions. The purified [18F]FDG was not contaminated with 3H. The amount of 3H discharged into the air was far less than the International Basic Safety Standard Level.