In general, non-toxic means that a given thing is not
poisonous. You see it a lot on things intended for kids (
Elmer's Glue,
Crayola crayons,
Magic Markers, etc.) and pets (stuff like
Febreze, which contrary to
urban legend is perfectly safe when you
use as directed).
This doesn't mean all non-toxic products are harmless, just that they won't kill you in moderate doses. They can still make you feel funny or downright ill, as anyone who's ever managed to drink Elmer's Glue undoubtedly knows well.