just wondering does this have any negative effects on the vinyl as i have a bunch of figures still bagged and noticed a strong vinyl smell when i opened the box they where in

I think the vinyl these toys are made from is always releasing some sort of chemical (living vinyl as Kozik use to say), so perhaps a closed box trapped the gases and when you opened it you got hit with the smell. I notice it whenever I open the detolfs.

I don't think the humidity will do much to the vinyl unless they were submerged in water for months at a time (or live steam). Even then you have more to worry about regarding the paint than the actual vinyl. Chemical cleaners, heat, and direct sun light are the biggest enemies.