Mothballs are a tried-and-true way to prevent moths and other pests from infiltrating closets, attics, crawl spaces and other small areas. However, mothballs should be used carefully, because the active ingredient in mothballs, naphthalene, has been identified as hazardous to humans and animals.

Adults

Adults exposed to large amounts of naphthalene will immediately develop nasal and bronchial irritation, and over time can develop hemolytic anemia, which presents with fatigue, loss of appetite, and pale skin.

Children

Small children and infants have developed hemolytic anemia because of naphthalene exposure, either by eating mothballs or from contact with clothing or other items stored with mothballs.

Pets

Ingesting mothballs can result in serious health problems or even death for pets. For cats and dogs, signs of mothball ingestion include vomiting and lethargy. Medical attention should be sought immediately.

Benefits

Although dangers are associated with mothballs, the benefits can outweigh the dangers. Mothballs are an easy, inexpensive way to prevent clothing and other items from being destroyed by pets. Furthermore, mothballs can be used safely.

Precautions

To use mothballs safely, take precautions to assure that your family's exposure to naphthalene is reduced as much as possible. Only use mothballs in small, enclosed spaces like closets and storage bins. Place mothballs in locations where they are not easily accessible to children or pets. Wash any clothing or other items stored in mothballs before using them.

Source:

ToxFAQS: Naphthalene

More Information:

Oregon State University: Proper Use of Mothballs