One of the little details about deuterium-tritium fusion that fusion boosters don’t like to talk about is that every fusion reaction emits a 14.1 MeV neutron which, as a neutral particle, cannot be confined or steered by the magnetic field containing the plasma and just flies out in any old random direction. This must be absorbed in the “blanket” and its kinetic energy converted to heat which is extracted to generate power. (Here is a talk I posted earlier in Fusion Friday about the blanket.)
But this intense neutron flux causes neutron activation in any material upon which it impinges, and can convert many elements into radioactive isotopes that remain radioactive when the machine is shut down. It also embrittles or otherwise damages metals, which means that the many tonnes of fusion reactor vessel become dangerously radioactive and must eventually be disposed of as low-level radioactive waste, just like the waste from a fission reactor.
This is why most plasma fusion experiments use deuterium only, which does not undergo neutronic fusion. Once you introduce tritium, the machine becomes “hot” and difficult and expensive to work upon. Under current plans, ITER will start testing with deuterium in 2025, but is not planned to begin experiments including tritium until 2035, when they’re confident they’ve got it right, because it is hideously difficult and expensive to change things once the guts of the machine have become radioactive.