> even though it is one of the least processed things on the list.
It is in a glass bottle, so maybe not the greatest example: https://www.sciencealert.com/glass-bottles-actually-contain-...
Straight from the cow would be far more interesting with respect to what you are bringing up, albeit beyond the scope of the broader discussion.
Many livestock feeds have some level of plastic in them.
Hay is often bound up into bales with plastic twine. Cattle happily eat bits on accident. They used to use wire, but that caused a much more serious problem for the cattle.
Fortunately, raw cow milk is unnecessary for humans (good for baby cows though!) and easy to avoid.
My only question is was the cow milked by hand or by machine? The tubing in a milking machine almost certainly contains plastic.
https://www.plasticlist.org/product/29