Silly question about vinegar-based silicone interacting with film, and light leaks.

Paint can take weeks to outgas. Line the box with black cardboard or just buy a black box to begin with, if this is a real issue at all.

I keep my film holders in zip lock plastic bags, Brawny brand, or similar. This guards against invasive dust and moisture and is inexpensive.
I like to keep my film holders in the dark in case leaks manifest themselves---unlikely but it's a belt and suspenders approach. There are plenty of lunch box size soft sided coolers than can digest 4x5 film holders. If you need a hard box consider a cooler like Coleman or Igloo. These may attract bears( the ones in Yosemite apparently can read) but it won't attract thieves like a real live camera bag