Monitor Warranty

So my boys at dell ship me a monitor that has stains on the screen . Their policy was to return it however they told me to wipe it off so whatever it was smudges all over. The big problem is that what ever this substance is seems to really irritate my eyes, so yeah no red eyes but eye pain or pupils stop dilating. How do I get it off? Or what do I do about this? Since Dell support refuses to take it off themselves even though they shipped it with that substance on.