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Pet vet: Moth balls can poison dogs, birds

Pet vet: Moth balls can poison dogs, birds

Ed Jorden PET VET

Just about monthly we get reports of new items that are toxic to our pets.

I have always thought that moth balls would be too smelly for a dog to want to investigate, but that is not the case.

The Animal Poison Control Center reported 158 cases of moth-repellent ingestion in the last two years. Most of the animals ingested the moth balls, but some had exposure by inhalation and others by contact with their skin.

Two products in moth balls make them toxic. Naphthalene was the active ingredient in most moth repellents, and paradichlorobenzene was another. The first is a natural component of fossil fuels such as petroleum and coal. The paradichlorobenzene is an organochlorine insecticide and is much less toxic than the naphthalene.

Both compounds are soluble in oils and give off an odor that repels the moths. When they are ingested, the digestion of the moth ball can take several days, so there is a slow release of the poison. Once in the body, the compounds go to other parts of the body. Fat tissue is the first place it goes and then to the liver, kidney and lungs.

It is the liver that changes these drugs into toxic components that damage the body's cells. Eventually, the toxins are excreted in the urine.

The ingestion of only one moth ball may cause clinical symptoms in children, and small amounts in dogs, if the moth ball is made of naphthalene, will cause symptoms.

A hemolytic anemia, or destruction of red blood cells, is the main symptom. Cataracts also form in laboratory animals and may do so in dogs as well. Ingestion causes vomiting, lethargy and loss of appetite. Seizures and trembling have also been reported.

Pet birds have also been poisoned by moth balls when inhaling the fumes.

Treatment of the condition involves removal of the exposure and efforts to get the moth ball out of the body. The initial vomiting may have emptied the moth ball out of the stomach, but many times things must be given orally to try and trap the toxins as they pass through the intestinal system. Seizures have to be controlled, and the blood will need to be monitored carefully.

If the hemoglobin is affected by the naphthalene, it may not be able to carry oxygen any more. Special drugs will be needed and maybe a blood transfusion. If your dog's gums have a chocolate-brown color, your dog is in trouble.

Since it is important to know what your moth balls are made of, a simple test can be done. Mix several heaping teaspoons of table salt in a little water until no more will dissolve in the water. Drop the moth ball in the water. Naphthalene balls float; paradichlorobenzene moth balls will sink.

The prognosis with therapy is good unless you procrastinate in getting help or if your dog already has liver or kidney disease. Healthy dogs respond to the therapy quite well. Cats, as usual, seem to be smart enough (or finicky enough) to not ingest moth balls.

Have questions about pets? Write to: PetVet; c/o The Billings Gazette; P.O. Box 36300; Billings, Mont. 59107-6300. Questions of general interest may become topics of future columns.


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