Number 46 (Story #3), September 6, 1991 by Phillip F. Schewe and Ben Stein THE JOINT EUROPEAN TORUS WILL USE TRITIUM in fusion reactions before the end of the year. D-T reactions produce more energy than the customary D-D reactions, but scientists have until now been reluctant to use radioactive tritium for fear of unduly contaminating their reactors. JET's chief rival, Princeton's Tokamak Fusion Test Reactor, plans to introduce tritium next July. (Science, 23 August 1991.)