Is Secondhand Smoke Harmful to Pets?

According to a 2002 study by the Tufts University, cats living with smokers were twice as likely to develop malignant lymphoma or feline cancer. This was due to their grooming habits that exposed their oral tissues to harmful levels of carcinogens.

If you are a pet lover, then you might be interested in knowing that secondhand smoke affects even your beloved cat or dog. Secondhand smoke, also known as environmental tobacco smoke (ETS), is the inhalation of smoke by anyone other than the active smoker.

This not only includes adults and babies but pets and other animals as well. In humans, passive smoking is believed to cause respiratory problems, ear infections, cardiovascular diseases and lung cancer. This is what led to stricter regulations and bans on public smoking.

In this story, we shall try to understand more about the impact of secondhand smoke on our pets, and the ways in which we can curb the menace.

Secondhand smoke comes from two sources: from the smoke that is exhaled by the smoker, and from the burning end of the cigarette itself. Of the 7000 chemicals in tobacco, around 250 are extremely toxic. Some of the toxic elements in tobacco include cancer-causing chemicals, poisonous gases and toxic metals like methane, arsenic, carbon monoxide, formaldehyde, butane, ammonia and toluene.

Other than the carcinogens in the smoke, pets can also accidentally eat nicotine products like cigarette butts or nicotine patches. This can be toxic for the pet and cause emergency trips to the veterinarian.

Although it is difficult to prove the association, when exposed to smoke for a long time, there are many health complications that can be seen in your faithful canine companion. This is because dogs have a heightened sense of smell and thus their nasal membranes are much more sensitive to the toxins in secondhand smoke.

One of the long-term effects of secondhand smoke, especially in long-nosed dog breeds (dolichocephalic) like collies, include nasal cancer. The carcinogens from the smoke are inhaled and settle in the nasal cavity, thus resulting in cancerous tumors.

Some of the clinical signs of this include: nasal and eye discharge often tinged with blood, clogged nasal passages and sinuses, loss of smell, loose teeth, sneezing, obstructive masses in the nose, facial deformity and pain in the nose.

The veterinarian may identify the cancer using rhinoscopy. Treatment options include surgical removal of the tumor (rhinotomy), radiation therapy and chemotherapy.

Instances of lung cancer are seen more in dogs with short and medium noses ((brachycephalic and mesocephalic breeds). This is because unlike their long-nosed counterparts, breeds with short noses are unable to filter the airborne particulates and carcinogens.

A potentially fatal condition, lung cancer can be primary (tumors in lung) or metastatic (Tumors originating in other body parts). Secondhand smoke causes primary tumors and in majority of cases the tumors are carcinomas (often adenocarcinoma). Some of the common signs include chronic cough along with lethargy, lameness, difficulty breathing and weight loss.

Other than these fatal conditions, the dog may also suffer from eye irritation, wheezing, hyperventilating and coughing. Sometimes the dog may develop allergic reactions, symptoms of which include biting and chewing of the skin. The risks are greater for puppies who have weak immune systems and are thus, extremely susceptible to infections.

Secondhand smoke has a worse effect on cats than dogs. This is because unlike dogs who are washed more often, cats have the habit of licking their fur to groom themselves. This leads to the ingestion of the carcinogens from tobacco smoke that may have settled on their cat's fur. This can lead to squamous cell carcinoma in cats.

A deadly type of malignant tumor, squamous cell carcinoma leads to tumors in the oral cavity. Studies have found that cats who have been exposed to tobacco smoke or have lived with a regular smoker have an increased risk of developing this cancer.

The cat may refuse to eat or drink, the appetite would decrease and there is often significant weight loss. This is accompanied by other clinical signs like halitosis, increased saliva, nasal discharge and a noticeable mass in the mouth.

The overall prognosis of this disease is poor especially if the tumor is discovered in the later stages. Treatment options include palliative radiation therapy with chemotherapy or surgical removal.

As mentioned above, cats that lived with regular smokers have twice the risk of developing lymphoma or the cancer of the lymph nodes than cats who live in non-smoking households. The risk increases with longer durations of exposure.

Lymphoma affects the entire lymphatic system which consists of the lymphatic vessels, lymph nodes and cells. The lymphoma that affects the lymph nodes is known as multicentric, while lymphoma of the chest cavity is termed as mediastinal lymphoma.

Other than this, the gastrointestinal tract is afflicted with alimentary lymphoma. It leads to weight loss, poor appetite and lethargy in cats. This condition is often fatal. However, in certain cases chemotherapy and radiation therapy can be used for treatment.

Apart from this, the cat may also suffer from asthma, respiratory problems and irreversible lung damage.

Like our cats and dogs, other pets especially birds are also known to be affected by secondhand smoke. The disproportionate amount of secondhand smoke that birds take in, along with their hypersensitive respiratory system, can lead to lung cancer, eye problems, chronic coughing, wheezing, fertility problems, and pneumonia.

Birds that sit on a smoker's hand may develop contact dermatitis due to the nicotine on his or her hands. This causes them to pull out their feathers. Rabbits, guinea pigs and other pets are just as vulnerable to secondhand smoke as well.

When they are not inhaling the deadly smoke, the pets can still be at risk of ingesting nicotine products like cigarette butts, nicotine patches and gums. In fact, if the dog or cat ingests 1 to 5 cigarettes or one-third of a cigar, it can lead to the death of the pet.

Our pets are an integral parts of our lives. Making our homes smoke-free can ensure their well-being and protect them from the deadly and often fatal effects of secondhand smoke.