Mothballs are sometimes used in wardrobes, storage areas and suitcases to deter moths and other insects. Whilst they may be effective for protecting clothing and other fabrics, mothballs pose a significant poisoning risk to pets. The Animal Poisons Helpline receives calls every year regarding curious dogs and cats that have chewed on or ingested mothballs.

There are three common active ingredients found in mothballs; camphor, naphthalene and paradichlorobenzene. Each of these substances can be toxic to pets. Pets may be exposed by eating mothballs directly or by breathing vapours in poorly ventilated spaces. Whilst poisonings are relatively rare, even small exposures can potentially result in severe effects.

Camphor, used in some older or imported mothballs, can cause rapid onset signs such as drooling, vomiting, tremors and seizures. Pets that ingest naphthalene can develop vomiting, lethargy, diarrhoea, and in severe cases seizures and red blood cell damage. Cats are particularly sensitive to naphthalene and exposure can be life-threatening without urgent treatment. Paradichlorobenzene is less toxic but can still be dangerous.

To reduce the risk of mothball poisoning in pets:

✅ Avoid using loose mothballs in areas accessible to pets, including wardrobes, garages and storage containers.

✅ Check ingredient labels and dispose of old or unlabelled mothballs safely.

✅ Opt for pet-safe alternatives, such as cedar blocks or sealed garment bags when storing clothes.

✅ Keep pets away from freshly treated items and ensure good ventilation if using these products indoors.

If your pet has ingested any type of mothball, it is important to immediately phone the Animal Poisons Helpline or your veterinarian, even if they look well. The Animal Poisons Helpline provides expert advice to pet owners and can be reached on: ☎️ 1300 869 738 (AU), 0800 869 738 (NZ) , 3106 4216 (SG), (917) 722-5958 (US) or +1917-722-5958 (CAN).

If you are a member of a veterinary team you can also join the Animal Poisons Centre For Vets Facebook group which is regularly updated with toxicology tidbits and poisoning trends. To stay up to date with the latest pet poison alerts and receive updates directly to your inbox, visit animalpoisons.com.au/stay-up-to-date and subscribe.