In the "Thorium cycle", you use Th-232 as a fertile material to breed fissile U-233.
Then you burn the U-233 for power and make more U-233.
Putting combinations of different materials together doesn't affect the radioactivity.
The radioactive decay characteristics depend on what's going on in the nucleus.
The nucleus has no way of knowing what's also in the mix. In terms of length scale;
all those other materials are a LONG, LONG, LONG way away from the nucleus.
Dr. Gregory Greenman