What Flavor Components Can Be Harmful to Plastic?

We see the warnings on some flavors as, “Has been reported to crack/melt plastic tanks. May be fine to vape with glass or stainless steel tanks.”
But what exactly it is within the flavoring that makes it unfriendly to plastic?
TPA has component lists on their site for all of their flavors, so curiously I compared the ingredients of two flavors that have that warning (the Pineapple I know firsthand damages plastic) to see if something would jump out at me, and it did not.
I am no chemist, and these component lists are a foreign language, but maybe someone here could guide us regarding chemicals or classes of chemicals found in our flavorings, that might be harmful to plastics.
Thanks

Cinnamon Danish (TPA):

COMPONENT CAS Description
Propylene Glycol >= 78% and < 88% – Benzyl Alcohol <7% – Ethyl Vanillin < 10% – Vanillin < 7% – Ethyl Maltol >= 1% and < 5% – Cinnamomum Verum Bark Oil < 7% – Cinnamaldehyde <(E)-> <0.7% – Acetoin <0.5% – Acetyl Propionyl 0.3%

Pineapple (TPA):

Butyrate < 4% – Propylene Glycol >= 44% and < 55% – ethyl caproate < 2% – Heptanoate >= 1% and < 10% – Heptan-2-one >= 1% and < 10% – Acetic acid < 2% – Butanoic acid, 3-methyl- <0.5% – Hexanoic acid <0.5% – Geranyl acetate <0.5% – Lactate <0.5% – Gamma Nonalactone <0.5% – Citronellyl acetate <0.5% – allyl hexanoate < 9% – ethyl acetate < 1% – lactic acid 15-20%

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Acetates I believe damage plastics

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