Safe to use as a hide?

[kiiarah]

The other day at work I noticed some cardboard sitting by the trash that looked perfect for a snake hide. These are the end caps that they use to hold large printer cartridges in place in the packaging. I trimmed them so only the moulded part was left. They even had the shape for the entrance already built in. So my question is would these be a safe material for a hide. My only concern had been that since they are some kind of reconstituted and dried cardboard they are softer and "dustier" than normal cardboard. I am not sure how sensitive ball pythons are to airborne dust and particulates so I thought I would run the idea by everyone here. I realize these would have to be temporary since they couldn't be sanitized, but I thought it may be a good test hide. The ones he has now are half logs, so they seem really exposed. He uses the ones he has now and seems happy enough, but I thought maybe the added security of more of a cave style hide might be good for him. I was hoping to throw these in his tank at some point and see if he seems to prefer them. If he likes them I may invest in some cleanable hides with only one entrance.