When I go to the range, every once in a while, I'll see one of the older marksmen who's there with his squirrel hunting rifle, chambered in .22 LR. I've noticed that he seems to have a tremor in his hands when he's loading his magazines. Essential tremor is linked to lead exposure [0]
Most .22 LR projectiles are either just lead or have a copper "wash" over the lead, not a proper jacket like you see on other rounds.
I wonder, if you shoot those loads for long enough, and breathe in enough gunsmoke, do you get that problem?
As for the proof being in our hair... well, not mine. Chrome dome over here XD