[addled]

I know a lot of people have praised cardboard and I've used it too, but after sniffing some particularly smudged boxes from an Amazon order, I'm pretty hesitant now.

I'm less nervous about things like pizza boxes (if not too greasy). Even if there are contaminants, they are already in my food.

[fy20]

I just use 'plain' cardboard in my garden - the brown stuff with text printed in one colour. It's pretty easy to get hold of from supermarkets. The multicolour stuff I send for recycling.

[ornornor]

Aren’t pizza boxes lines with PFAS or some other kind of forever chemicals which is why they can’t be recycled?

[cricalix]

The ones in Ireland are basic cardboard. You can tell from the way the grease soaks through and the cardboard goes all limp. The constraint for recycling them here is that the items up for recycling must be "clean and dry", and a pizza box is neither after it has been delivered with pizza in it.