anyone know how to whiten yellowed plastics?

[Jedburton]

I finally decided my fishing stuff had gotten way too cluttered and am going through it and organizing everything better and discovered a bunch of white perlescent plastics that have yellowed and was wondering if anyone has had any success in whitening their plastics. I hate to throw them away and will probably try to fish them as is if I can, but would prefer to whiten them back up if it won't ruin them for fishing. Any advice would be greatly appreciated. I have been searching online, but can't seem to find any info.
Jed Burton
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