> Mcflurry ingredients: https://www.mcdonalds.com/us/en-us/product/mcflurry-with-ore... (no mention of plastic)

That's actually incorrect, they list two plastics there. It's just that "plastic" isn't something that is actually necessarily toxic, and the media misuse the terminology all the time.

The two are:

> Cellulose Gum, Guar Gum