How to get body odor out of an old plastic sewing machine cover? [View all]

I have a Singer sewing machine that was made in the early 1970s. The machine still works great. The white plastic cover stinks of body odor. I think that maybe one of my teenage sons draped a sweat-soaked t-shirt on it, and the sweat soaked into the plastic. The cover has a smooth surface, but in places where it is scuffed I see that the underlying plastic seems to be a bit porous.

I've tried to get the smell out for two years. I've soaked the cover in bleach in the bathtub, in vinegar, showered it in hot water, sprayed all kinds of cleaners on it, left it out on the patio for the rain and sun to work on, and even put essential oils on it. (I had forgotten the odor of patchouli and sweat - while this was a walk down memory lane, I don't want it in my house. I loved the 60s but....) All I've succeeded in doing is rusting the latches that snap the cover onto the base of the machine. The cover is now very clean and pearly white, but the odor always comes back.

Any advice? I'm about ready to throw it out, but that will leave my old sewing machine unprotected from dust and cat hair.

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