Mothballs are a common household pesticide used primarily to protect stored clothing and other materials from damage caused by clothes moths and their larvae. These small, solid items work by slowly releasing a vapor that acts as a fumigant, repelling or killing insects in an enclosed space. Because they are designed to release a toxic gas, understanding the safety risks associated with physical contact and vapor exposure is necessary before handling them. The chemicals within mothballs are toxic to humans and pets, making careful storage and use a serious concern for household safety.
The Active Ingredients in Mothballs
Mothballs contain one of two primary chemical compounds: naphthalene or paradichlorobenzene (PDCB). Both are solids at room temperature that transition directly into a gas without first becoming liquid, a process called sublimation. This sublimation releases the toxic fumes needed to deter pests in storage. The vapor concentrates within airtight containers, which makes mothballs hazardous if not properly contained. While older formulations used naphthalene, many modern products utilize PDCB. Regardless of the specific active ingredient, both compounds are classified as toxic pesticides requiring careful handling.
Immediate Effects of Skin Contact
Touching a mothball can cause immediate localized irritation. While the chemicals can be absorbed through the skin, they more commonly cause dermal reactions. Direct contact with paradichlorobenzene may lead to a burning sensation on the skin’s surface. Naphthalene exposure can cause mild dermal irritation and contact dermatitis in sensitive individuals. Systemic absorption through the skin is a particular concern for infants and small children, who have thinner skin. After any accidental contact, wash the affected area immediately with soap and water to minimize potential exposure.
Dangers of Inhalation and Ingestion
The most significant health risks from mothballs come from inhaling the chemical vapors or accidental ingestion. When fumes are released into open air, they can cause symptoms such as headaches, nausea, dizziness, and irritation of the eyes, nose, and throat. Chronic inhalation exposure can lead to long-term conditions, including damage to the liver and kidneys. Naphthalene exposure is particularly concerning because it can cause acute hemolytic anemia, where red blood cells are destroyed faster than they can be produced. This severe reaction is common in infants and individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency. Ingestion poses an immediate medical emergency, as eating even a single mothball can lead to severe poisoning, multi-organ failure, and life-threatening conditions like methemoglobinemia. If ingestion is suspected, contact a poison control center immediately for emergency medical guidance.
Safe Usage and Storage Guidelines
Mothballs are registered pesticides and must only be used according to the directions on the product label. The safest way to use them is by placing them in tightly sealed, non-porous containers along with the items being protected. Using mothballs in open areas, such as closets or attics, allows the toxic vapors to escape into living spaces, creating an exposure risk. Always store mothballs in their original packaging, ensuring they are kept in a locked cabinet out of the sight and reach of children and pets. When removing stored items, they should be thoroughly aired out, preferably outdoors, before being brought into the home. Washing hands with soap and water is recommended after handling the material.