I usually keep an open box of mothballs in my bedroom closet.
In the past, most mothballs contained camphor, which is ''quite toxic," causing nausea, vomiting and seizures when eaten or inhaled at close range, said Dr. Michele Burns, an emergency room physician at Children's Hospital.
With the newer naphthalene-based mothballs, the real risk is for people with a genetic problem called glucose-6-phosphate dehydrogenase deficiency, which is more common in people of African-American or Asian descent, said Dr. Stephen Traub, of Beth Israel Deaconess Medical Center. These people can develop a serious kind of anemia from eating naphthalene mothballs.
The safest mothballs are those containing paradichlorobenzene, which is ''pretty benign," said Dr. Edward Boyer, a toxicologist at Children's Hospital, though the fumes can irritate eyes or airways if exposure is high.
While occupational exposure, like working in a mothball factory, may pose a risk, the fumes from a box of open mothballs in the bedroom closet won't hurt you. Eating mothballs, however, does pose more risk, so keep mothballs away from children and pets.