These products will help significantly reduce to contain, but not prevent, off gassing of volatile organic compounds (VOCs) from conventional mattresses - choose from 100% organic to using safer plastic options.
It's a challenge to find both organic material and waterproof together as to waterproof something, you need plastic and most plastics are the source of off-gassing VOCs.
If looking for pillow encasement that is Organic, dust mite / bedbug resistant (but not waterproof) If looking for mattress encasement that is Organic, dust mite / bedbug resistant (but not waterproof)
This mattress pad is waterproof, dustmite / bedbug resistant - it's made with tencel, which is made from eucalyptus leaves but isn't considered organic. It's the more eco friendly option:
The product description talks about the plastic. Overall, it's a film and doesn't smell like it's offgassing per se.