I bought pressure treated 4x4 wood to build a a squat/bench rack without knowing it is not safe for indoor use and regular touching. Do I need to buy new lumber or is it safe to use as a squat/bench rack in the garage where the actually lumber would not be touched very often after being built?

Are there alternate options to still be able to use the wood safely for the job, like painting/ covering/taping over the beams?

I've tried researching, but can't get a clear answer