Mothballs will not reliably keep raccoons away. Despite decades of use as a folk remedy for wildlife problems, the evidence from wildlife control professionals and university extension programs consistently shows that raccoons tolerate the smell and continue nesting, feeding, and moving through treated areas without meaningful disruption.
Why Mothballs Fail as Raccoon Repellents
Mothballs work by releasing naphthalene or paradichlorobenzene fumes, which are designed to kill fabric-eating insects in enclosed spaces like garment bags and sealed storage containers. The concept behind using them for raccoons is simple: the strong chemical odor should drive animals away. In practice, it doesn’t work that way.
Wildlife control operators regularly encounter attics packed with mothballs, soaked in bleach, or reeking of ammonia where raccoons are nesting completely unbothered. Raccoons living in and around human structures have learned over generations that the shelter, warmth, and food access our buildings provide outweigh the discomfort of a bad smell. A raccoon nursing a litter in your attic has a powerful biological incentive to stay put, and a chemical odor simply isn’t enough to override that.
There’s also a basic physics problem. The University of Florida’s wildlife extension program notes that mothball fumes dissipate quickly in open or semi-open environments, making them far less potent outdoors or in ventilated spaces like attics and crawl spaces compared to a sealed garment bag. Even in situations where the initial concentration is high enough to bother an animal, all wildlife tends to habituate to deterrents over time. If the raccoon sticks around long enough for the smell to fade or for its nose to adjust, the mothballs become background noise.
Health and Legal Risks of Using Mothballs This Way
Beyond being ineffective, scattering mothballs around your property to repel raccoons is actually illegal. Mothballs are registered pesticides regulated by the EPA, and their labels specify use only against fabric pests in enclosed containers. Using them in gardens, attics, crawl spaces, or anywhere outdoors to deter wildlife violates federal pesticide law. This isn’t a technicality. The restriction exists because off-label use creates real dangers.
Naphthalene exposure can cause a type of anemia where red blood cells break down faster than the body can replace them. Newborns are especially vulnerable because their bodies are less equipped to process and excrete the chemical’s byproducts. In documented cases, young children developed this condition simply from wearing clothes or sleeping in bedding that had been stored with mothballs. Pregnant women face risks too: fetuses have developed anemia in the womb from their mothers inhaling naphthalene fumes. People of African or Mediterranean descent carry a higher genetic risk for this reaction due to a more common enzyme deficiency.
Pets are also at risk. Dogs and cats that inhale concentrated fumes or eat mothball pellets can be seriously harmed. Mothballs are flammable as well, which is a real concern if you’re tossing them into a dry attic full of insulation. And when used outdoors, they can leach into soil and contaminate groundwater and plants.
What Actually Works for Raccoon Problems
The most reliable long-term solution is physical exclusion: sealing the entry points raccoons use to access your home. This means capping chimneys with commercial chimney caps, repairing damaged soffits and fascia, covering vents with heavy-gauge hardware cloth, and trimming tree branches that provide roof access. Once you’ve confirmed no animals are trapped inside, closing these gaps prevents re-entry permanently.
If a mother raccoon is already denning with babies in an attic or chimney, the timing gets more delicate. One option wildlife professionals use is raccoon eviction fluid, a commercial product made from male raccoon gland secretions and urine. The idea is that a nursing female interprets the scent of an unfamiliar male as a threat to her young and relocates the litter on her own. In a small university study testing these products on chimney-denning raccoons, one brand achieved a 50% eviction rate, while another performed no better than plain water. When it did work, the mothers moved their entire litter out and did not return to the structure during the multi-year follow-up period. It’s a tool worth trying before more invasive removal, but results are inconsistent.
Ultrasonic repellent devices, another popular product, have repeatedly failed to meet their manufacturers’ claims in controlled testing. Don’t count on them.
Reducing What Attracts Raccoons
Raccoons come to your property because it offers food, water, or shelter. Removing those attractants is often more effective than any repellent. Secure garbage cans with bungee cords or locking lids. Bring pet food indoors at night. Clean up fallen fruit from trees. If you have a koi pond or water feature, consider motion-activated sprinklers as a short-term deterrent, though raccoons may eventually learn to ignore those too.
For raccoons already inside a structure, hiring a licensed wildlife control operator is the most practical route. They can identify entry points you might miss, handle removal without separating mothers from dependent young, and install exclusion materials rated to withstand a raccoon’s strength. A raccoon can tear through lightweight screening, rotted wood, and even some types of flashing, so the quality of the repair matters as much as the repair itself.