Mothball toxicity in dogs isn’t exactly a rampant problem, but up to a few hundred dogs and cats die from it—and others get sick—every few years in the US. We wanted to address it since it’s not nearly as widely publicized a danger as more familiar threats to your assistance dog, like chocolate, antifreeze, or certain household cleaning products.
The main takeaway here is that mothballs are highly poisonous and potentially fatal to dogs and cats (as well as birds and other pets). Ingestion is the most serious route of toxicity, but even inhalation of fumes and skin contact can cause toxicity. For those with a hearing, guide, or service dog—or a pet—it’s always safest not to keep them around your home. However, by taking sensible precautions, following all the package directions and warnings, and keeping them in their sealed containers, they can be safely used.
What Exactly Are Mothballs?
Mothballs are small pesticide delivery items that give off a vapor that repels and kills moths and their larvae, as well as some other insects, and even mice and other pests. They’re usually used to protect clothing from moths. Often, they’re ball shaped, but the same moth repellents come in powders, cakes, cubes, and other forms, all of which present the same risks.
Two different pesticides are used for making mothballs: naphthalene or paradichlorobenzene (PDB). Naphthalene is used less and less often these days, as it’s twice as toxic as PDB and also highly flammable. If you’re going to purchase mothballs, definitely choose a product that uses PDB as its active ingredient. But remember that it too is poisonous.
Symptoms of Mothball Toxicity in Dogs
Mothballs use highly concentrated doses of pesticide, which is why even one can cause serious problems or even death. Again, the type of pesticide, plus the concentration and the size of the mothball, affect how much it takes to trigger toxicity. Also, the size of the animal matters; the smaller your assistance dog, the less naphthalene or paradichlorobenzene it takes.
The two pesticides tend to cause different symptoms following ingestion. However, inhalation can cause pain and irritation to the nose, mouth, throat, or lungs; skin contact can cause the same at and around points of contact.
Common symptoms and complications of naphthalene mothball toxicity, which typically affects the gastrointestinal system first, include:
- Loss of appetite
- Excessive thirst or urination
- Red blood cell damage
- Brown or pale mucous membranes
- Liver damage
On the other hand, paradichlorobenzene generally affects the central nervous system first. Common signs and complication of PDB mothball toxicity in dogs include:
- Difficulty walking
- Liver damage
What to Do if You Suspect Mothball Toxicity
If you think your service, hearing, or guide dog ate one or more mothballs, or if you suspect mothball toxicity, call your veterinarian right away (or the Pet Poison Hotline at (855) 764-7661, which charges a $59 fee). If your assistance dog consumed the mothball(s) within the last couple of hours, it may be recommended that you induce vomiting. Bring your dog in to your vet or the nearest emergency veterinary hospital immediately.
Timely, aggressive treatment is usually successful. Treatment may include induced vomiting, flushing out your assistance dog’s stomach, administration of activated charcoal, fluid therapy, and drugs to control symptoms and complications like vomiting, seizures, or organ damage. A blood transfusion may be needed for severe anemia.
If possible, identify which pesticide your mothballs contain. If you don’t know, there’s a trick for figuring it out:
- Thoroughly mix 3 to 4 tablespoons of table salt into half a cup of lukewarm water
- Add salt as needed until no more will dissolve
- Drop one of the mothballs into the saltwater
- Naphthalene mothballs will float, while PDB mothballs will sink