Moth balls (Napthalene) is a carcinogen, iirc... don't overdo it. It will make you sick. Our office landlord's maintenance people tried to use a product called bat-a-way (basically mothballs) some years ago to remove a colony of bats (over my objections btw, better ways to do that). Anyway they dumped the container loose into the insulation in our suspended ceilings. They managed to poison everyone in the building. I had stomach issues, a co-worker had heart problems, no one could work more than a few hours a day in the building. Eventually they managed to remove it all and left the bats in peace...