Do moth balls kill or repel insects?
Answer Carol: Moth balls are made with the active ingredient naphthalene, and are designed to repel insects. Their effectiveness is disputable, however, especially when it comes to carpet beetles (family Dermestidae). I have heard reports of carpet beetle larvae actually ‘eating’ naphthalene on the way to some delicious wool blanket or other tasty morsel. Moth ‘crystals’ are different. The active ingredient is PDB (paradichlorobenzene), and is much more toxic. It is at least rumored to be carcinogenic (cancer-causing). It is a more effective repellent, and can kill at least some insects if the concentration of fumes in the container is high enough. I recommend neither of these products. It is best to store woolens, furs, silks, and other animal-based fabrics in a cedar chest. Cedar is an effective repellent, and really never needs replenishing. Plus, it smells a lot better than moth balls or crystals, and it is not toxic to humans (as far as I know, anyway). Hope that answers your ques