https://www.bjcp.org/faults.php
This lists common faults and off flavors and common causes.
I brewed with a plastic spoon for a couple years, I don’t ever recall any off flavor I could attribute to it. I have the Anvil brew spoon now, SS and heavy duty. I suppose boiling a plastic jar for 10 min could be a contributor, but thats actually a pretty small jar and 11.5 gallons is alot of wort ?
I once bought a small plastic aquarium pump on ebay that I tried to use to recirculate my mash. Even though I washed it and ran hot water through it prior to use, that was still my worst case of plastic taste I ever got in a beer. I had to dump that one and I never used that little pump again.
If you are lucky, it may fade with some time.