Step father uses meth

Okay long story short.... I have a pretty messed up family. My mom is still with my crazy “step father” I say that very lightly because I don’t actually consider him anything except dirt. But it’s easier just saying what he legally is.

Anyways..... I don’t go to my moms house because he does drugs. I’m just curious once my baby is born, since my mother is still with him and around him all the time if she wants to come see my baby can she carry some particles on her from his drug use that could harm my baby?