Mothballs and Their Toxicity to Dogs
Mothballs are commonly used in households to protect clothing and fabrics from moths and other insects. While they may seem harmless when tucked away in storage containers, these small pesticide products pose a significant danger to pets—especially dogs. Understanding the risks associated with mothballs is essential for keeping your canine companions safe.
What Are Mothballs Made Of?
Mothballs come in various forms: balls, cakes, flakes, powder, and spheres. The main chemicals found in mothballs include:
- Naphthalene (older formulations; highly toxic)
- Paradichlorobenzene (PDB) (modern formulations; less toxic than naphthalene but still dangerous)
- Camphor (less common in North America; also toxic)
The shift from naphthalene to PDB in recent years reflects growing safety concerns. However, both substances remain hazardous to pets and humans alike.
How Do Dogs Get Exposed?
Dogs are naturally curious. They might sniff out or even eat mothballs left within reach. Poisoning usually results from ingestion but can also occur through inhalation of vapors or skin contact. Since dogs are more likely than cats to ingest foreign objects, they're at particular risk—even one mothball can be dangerous for a small dog.
Toxic Effects of Mothballs on Dogs
The severity of toxicity depends on the chemical type, amount consumed, and the size of the dog. Here’s what happens with different chemicals:
- Naphthalene: Most toxic; can cause gastrointestinal upset (vomiting, diarrhea), abdominal pain, loss of appetite, weakness, lethargy, pale or brown gums, anemia, tremors, labored breathing, seizures, liver/kidney damage, and methemoglobinemia (poor oxygen delivery).
- PDB: Less toxic but still causes vomiting and diarrhea; at higher doses may result in tremors, muscle weakness, red blood cell damage or organ injury.
- Camphor: Rarely found in North America but can cause agitation, GI distress, tremors, and seizures if ingested.
Toxic symptoms may develop within hours or take a few days due to slow stomach dissolution. Small dogs are especially vulnerable: ingesting as little as 0.6 g/kg naphthalene can trigger hemolytic anemia—and since one mothball weighs between 2.7–5 grams, even one could be a toxic dose for a tiny pup.
Symptoms of Mothball Poisoning in Dogs
- Vomiting
- Diarrhea
- Lack of appetite/refusal to eat
- Mothball odor on breath
- Pale/brown/yellow gums
- Lethargy/weakness
- Tremors/seizures/loss of balance
- Abdominal pain
- Labored breathing
- Jaundice (yellow gums/skin/eyes)
If you notice any combination of these symptoms—or suspect your dog has eaten a mothball—seek veterinary help immediately.
Treatment for Mothball Toxicity
If you witness ingestion or suspect exposure:
- Contact your veterinarian right away—don’t wait for symptoms.
- Don’t induce vomiting or give anything by mouth unless instructed by a vet.
- If possible, bring along packaging or a sample for identification.
The vet will likely perform a physical exam along with bloodwork and urinalysis. Sometimes X-rays help locate mothballs inside the digestive tract.
Treatment options may include:
- Inducing vomiting/gastric lavage (only if recent ingestion & dog isn’t symptomatic)
- Activated charcoal under supervision to bind toxins
- IV fluids for kidney/liver support & toxin elimination
- Medications for nausea/vomiting control & seizure prevention
- Liver support medications/protectants for GI tract lining
If anemia develops due to red blood cell destruction (especially with naphthalene), oxygen therapy or blood transfusions might be needed. There’s no antidote—outcome depends on promptness of care and amount/type ingested.
Prognosis: What Happens Next?
The sooner treatment begins after exposure, the better your dog’s chances. Delays increase the risk of permanent organ damage or death—especially if large amounts were consumed or your pet had pre-existing health problems. Some dogs may recover fully; others might suffer long-term liver/kidney issues.
Prevention Tips: Keeping Dogs Safe from Mothballs
- Avoid using mothballs outside airtight containers; never scatter them around the home/yard/garden as pest repellents.
- Keep all pesticides out of reach of pets and children—store securely in closed containers.
- Follow label instructions exactly; don’t mix different types together.
- If you stop using them or have leftovers—dispose properly according to local guidelines.
- If you want alternatives: try airtight storage bins or pheromone traps instead of chemicals.
Mothball vapors aren’t just bad for pets—they’re potentially carcinogenic and harmful to people too. Chronic exposure increases health risks over time and harms the environment as well.
If Your Dog Is Exposed… Act Fast!
If your dog eats a mothball—or you suspect any exposure by inhalation or skin contact—don’t wait for symptoms to appear. Call your veterinarian immediately for guidance on next steps. Quick action makes all the difference when it comes to recovery from this household hazard!
