Tag Archives: cancer in dogs

Passive Smoking Happens to Pets Too

Fluffy, Fido, and Tweety all suffer from the secondhand smoke of their owners, according to a growing body of literature that has looked at the issue, said Carolynn MacAllister, a veterinarian with the Oklahoma State University Cooperative Extension Service.

Cats are twice as likely to develop malignant melanoma if they live with smokers as with nonsmokers.

This form of cancer kills three out of four felines within a year of its onset. Cats also are more likely to develop mouth cancers.

MacAllister said that cats’ grooming habits contribute to their risk. “Cats constantly lick themselves while grooming, they lick up the cancer-causing carcinogens that accumulate on their fur” and deposit relatively high concentrations of those chemicals into their mouths.

Dog with Face MaskLong nosed dogs suffer higher rates of nasal cancers as the carcinogens accumulate along those mucus membrane passageways. They seldom survive more than a year. In contrast, short nosed dogs do not filter the carcinogens as effectively, as a result, more of those deadly chemicals reach their lungs and they are more likely to develop lung cancer.

And feathered pets are not immune either. “A bird’s respiratory system is hypersensitive to any type of pollutant in the air,” MacAllister said. Living with a smoker makes birds particularly vulnerable to pneumonia and lung cancer. That is particularly true because caged birds cannot engage in vigorous flying that helps to clear the lungs of toxins.

“Curious pets can eat cigarettes and other tobacco products if they aren’t stored properly.” MacAllister warned. “This can cause nicotine poisoning, which can be fatal.”

Smokers themselves are 50 percent more likely to develop dementia than nonsmokers, according to a recent study of 7,000 people 55 or older that was conducted over seven years in the Netherlands.

“Smoking increases the risk of cerebrovascular disease and oxidative stress, which can damage cells in the blood vessels and lead to hardening of the arteries,” said lead researcher Dr. Monique Breteler of the Erasmus Medical Center in Rotterdam.

Erectile dysfunction is a more immediate risk from smoking. A four-year study of 7,684 men in China, ages 35-74, found a statistical link between the number of cigarettes smoked and ED. It estimated that almost a quarter of all ED could be attributed to cigarettes.

And the habit is expensive, even before figuring in the added cost of Viagra. A study from New York City estimates that the average pack-a-day smoker burns up $2,500 a year with their habit.

It showed that low-income persons are more likely to try to quit smoking than those with a high income (68 versus 60 percent), but they are less likely to succeed in doing so.

Many private health plans and local health departments have developed programs to help people quite smoking. They often include free or reduced rates for counseling sessions and interventions such as nicotine gum or the patch.

For information about programs in San Francisco, visit the Tobacco Free Project’s Web site at http://sftfc.globalink.org/. For information statewide, call 1-800-NO-BUTTS. ~

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~Bob Roehr, The Bay Area Reporter

Second-Hand Smoke Affects Pets Too

Second-hand smoke, also known as environmental tobacco smoke or ETS, is clearly associated with cancer, respiratory and cardiovascular disease in humans.

Several studies have shown that up to 20 different carcinogens contained in tobacco smoke can be inhaled by non-smoking bystanders.

Dr. Timothy Fan, veterinary oncologist at the University of Illinois Veterinary Teaching Hospital in Urbana, explains that although associations between ETS and diseases in animals have not been as extensively researched, a handful of studies show a correlation between ETS and certain forms of cancer in pets.

A Tufts School of Veterinary Medicine study found a strong correlation between ETS and an oral cancer, squamous cell carcinoma, in cats. Cats living with smokers had higher incidence of this type of cancer. Cats living with more than one smoker and cats exposed to ETS for longer than five years have an even higher incidence of this cancer.

Why mouth cancer? Since cats groom themselves quite diligently, cats in smoking households can lick up carcinogens that have been deposited on their fur. Daily grooming over a long period of time can expose the delicate skin in the mouth to hazardous amounts of carcinogens.

The University of Massachusetts in Amherst also found that cats exposed to ETS have a slightly elevated risk of developing malignant lymphoma, or cancer of the lymph nodes. Since the lymph nodes filter the blood, inhaled or ingested carcinogens can build up in these structures.

Dog with GlassesIn dogs, ETS is significantly associated with nasal sinus cancer and weakly associated with lung cancer. A study at Colorado State found a higher incidence of nasal cavity tumors in dogs exposed to ETS than in dogs that live in non-smoking households.

This higher incidence was specifically found amongst long-nosed breed dogs such as Collies, and there was no significant increase in nasal tumors amongst short- to medium-nosed dogs exposed to ETS.

Dr. Fan explains that longer-nosed dogs may have a higher incidence of ETS-induced tumors for two reasons. “Smokers inhale smoke through their mouths, and it ends up depositing in the lungs. Bystanders, on the other hand, usually inhale ETS through the nose.” Long-nosed dogs’ nasal passages have a greater surface area on which carcinogens may be deposited before reaching the lungs.

“In addition,” says Dr. Fan, “since a longer nose has nasal passages with a greater number of cells, there is a greater chance that one of these cells can be mutated by carcinogens into a cancer cell.”

Colorado State also found that although short- to medium-nosed dogs exposed to ETS dont have a greater incidence of nasal tumors than those unexposed, they do have a slightly higher incidence of lung cancer, possibly because their shorter nasal passages are less effective at filtering carcinogens out of inhaled air before it reaches the lungs.

Unlike humans, who can develop bladder cancer as a result of ETS exposure, dogs and cats generally don’t run a higher risk of bladder cancer when exposed.

As the human-animal bond becomes stronger, we share more of our lives, our leisure time and our living space with our companion animals, and they become exposed to the same environmental hazards that we do. Many of our habits, including smoking, can affect our pets as they would affect any other member of our household.

Designating a smoking area outside or in a physically separate room of the house may be on way to minimize ETS exposure for pets and other non-smoking family members.

For more information about environmental tobacco smoke and your pet, consult your veterinarian.

Source: Kim Marie Labak
Information Specialist
University of Illinois
College of Veterinary Medicine