Mothballs, commonly found in many homes, are often used to protect clothing and other stored items from fabric-eating pests. While their strong, distinctive scent is widely recognized, many people may not fully understand the potential health implications associated with breathing their fumes. These small, solid pest control products can indeed pose dangers when their chemical vapors are inhaled, making it important to understand why and how to mitigate risks.
What Mothballs Are
Mothballs are solid products designed to release a gas that repels and kills clothes moths and their larvae. They primarily contain one of two active chemical ingredients: naphthalene or paradichlorobenzene (1,4-dichlorobenzene). Both compounds exhibit sublimation, meaning they transition directly from a solid into a gas at room temperature. The invisible fumes produced through this process are what make mothballs effective as pesticides. As pesticides, they are regulated by agencies like the U.S. Environmental Protection Agency (EPA).
Why Inhaling Mothball Fumes is Harmful
The fumes released by mothballs are toxic, and inhaling them allows the chemical compounds to enter the bloodstream, affecting various bodily systems. Naphthalene, a common ingredient, can cause a condition known as hemolytic anemia. This occurs when red blood cells are damaged and destroyed faster than the body can replace them, which can reduce the blood’s ability to carry oxygen. Individuals with a genetic condition called glucose-6-phosphate dehydrogenase (G6PD) deficiency are particularly susceptible to this effect, as their red blood cells are more fragile.
Naphthalene is classified by the International Agency for Research on Cancer (IARC) as “possibly carcinogenic to humans” (Group 2B). Animal studies show naphthalene exposure can induce tumors in rodents’ nasal cavity and lungs. Though human evidence is limited, caution is warranted due to potential long-term health consequences.
Paradichlorobenzene, the other active ingredient, also poses health risks with prolonged exposure. It is associated with adverse effects on the liver, kidneys, and central nervous system. Both mothball chemicals can cause serious health problems, from irritation to organ damage, with continuous exposure.
Infants and young children are particularly vulnerable to mothball fumes due to their smaller body mass and proximity to the floor where vapors accumulate. Pregnant individuals should avoid exposure due to potential developmental issues. Pets are also susceptible to these toxic effects.
Signs of Exposure
Symptoms of mothball fume exposure vary by level, duration, and individual sensitivity. Common acute symptoms include headaches, dizziness, nausea, vomiting, and irritation of the eyes, nose, throat, and coughing. These effects often resolve once exposure ceases.
Higher or prolonged exposure, especially to naphthalene, can cause more severe symptoms. These include abdominal pain, fatigue, confusion, dark urine, or jaundice, indicating red blood cell breakdown. In extreme cases, seizures, liver, or kidney dysfunction may occur. Seek immediate medical attention if severe symptoms are observed or exposure is suspected, particularly in children or pets.
Safe Handling and Alternatives
Mothballs are regulated pesticides and must be used according to label instructions. Use them only in tightly sealed containers, like airtight bags or storage bins, to concentrate fumes and prevent escape into living areas. Never place them in open closets, attics, gardens, or rooms, as this disperses toxic vapors.
After use, thoroughly ventilate the storage area before re-entry or using treated items. Air out and wash stored clothing or fabrics to remove residual chemicals. Always store mothballs out of reach of children and pets to prevent accidental ingestion. Dispose of them following local hazardous waste guidelines.
Safer alternatives exist for protecting items from pests without chemical pesticides. Cedar products (chips, blocks, hangers) offer a natural repellent. Herbal sachets with lavender, rosemary, or mint can also deter pests. Regular cleaning, vacuuming, and storing items in airtight containers prevent infestations. For persistent problems, consult a professional pest control service.