If you smoke, drive a car, climb a ladder, or fire up a barbecue grill, focus on reducing those very real risks, rather than the risk of thorium-emitted alpha particles.
If the OP was at all seriously concerned (hard to read people onlne), then this was yet another example of the common human fixation on remote, even minuscule, risks while ignoring the real ones whose abatement, however, would require habit change or other inconvenience.
And this tendency would be merely an amusing quirk were it not for its implications for public policy. And yes, widespread irrational public fear, leveraged by the lunatic part of the enviro movement, HAS likely prevented more widespread adoption of nuclear power generation in the US.
(Hadn't planned on mounting the soapbox quite so early this morning!). ;-)