Dangers of spray foam in body panels?

higher end dusters/demons had a "trunk dress-up" package, it was a series of plastic panels that mounted inside the trunk and covered the sides and tail panel area.

My Sport has the panels, they are made from a thick stiff paper type material and covered in carpet. The sides have a "flap" if you will, that extends under the trunk floor carpet. It contains debris to the trunk area and can be vacuumed out.