>>15090540alpha cannot penetrate paper let alone skin. however it is essentially a helium atom without electrons and the particles from it can be devastating after a while if it gets inside you.
it'll rip electrons from wherever it can be had, leading to the possible creation of cancer cells and further degeneracy and deterioration of your body's cells as they die and reproduce
for the assumption these particles got on your clothing, your skin, etc, you keep this on and go rubbing your eyes, scratching your skin, rubbing your nose, and god forbid consuming food or water, this could lead to small amounts of it getting into you. not on a level of some retards i've heard while decomming reactors.
>tl;dr>you wont die immediately, but because of lack of safety precautions, you'll probably get cancer 