[userbinator]

IMHO the more important part is they used pyrolysis gas chromatography, which breaks down all polymer chains.

Besides man-made plastics, guess what else has long hydrocarbon chains, occurs naturally in humans and other biological matter, and behaves similarly under pyrolysis...

https://en.wikipedia.org/wiki/Fatty_acid

Here's an interesting related article: https://www.oaepublish.com/articles/jeea.2022.04

Analysis of saturated, monounsaturated and polyunsaturated fats was demonstrated to form the same pyrolysis products as PE

[timr]

To their credit, they do discuss this in the results. I suspect the reviewers had the same concerns.

Their response is not especially convincing, IMO, but they do at least discuss it.