I'm hoping for some advice, I picked up an old fire rated door that was left outdoors for a few days and became quite wet however I gave it a new home in my new office I built and I've now discovered small fleas appearing out of the glass window edges where the small window is fitted into the door. Rather than throw out the door as ii have had galvanised sheeting cut out to fit over the door on both sides that's cost me £100.00 I hope to save the door. Is there a product I can buy to spray into the infected area or can I treat the door in some way to get rid of the fleas ? Thanks in advance for any replies.