Secondhand Smoke is Health Threat to Pets

By Mark Hale, DVM

Bolivar, MO

            Information for this article obtained from Veterinary Forum, October 2007.

            The medical community has known about the dangers pf secondhand smoke to adults and children for more than a decade. Recently a number of scientific papers have reported the significant health threat that secondhand smoke poses to pets also. These studies show that secondhand smoke has been associated with oral cancer and lymphoma in cats, lung and nasal cancer in dogs, as well as lung cancer in birds.

            A Tufts University College of Veterinary Medicine study showed a strong correlation between secondhand smoke and certain forms of cancer in cats. The umber of cats with squamous cell carcinoma was higher for those living with smokers versus cats living in a smoke-free home, and cats that live with smokers are twice as likely to get lymphoma than cats that live with nonsmokers. One of the main reasons that cats are so susceptible to secondhand smoke is because of their grooming habits. The carcinogens that accumulate on their fur are "eaten" while licking themselves, exposing their mucous membranes. Personally, I have noticed an increased number of cats, which are exposed to smokers, with feline asthma. This common ailment of cats can be fatal as well.

Secondhand smoke also affects dogs. A study conducted at Colorado State University showed a higher incidence of nasal tumors among dogs living with a smoker versus dogs living with a nonsmoker. The increased incidence was specifically found among the long-nosed breeds of dogs. Shorter- or medium-nosed dogs showed higher rates of lung cancer. The longer-nosed breeds have a large nasal surface area that is exposed to the carcinogens. Because the carcinogens tend to build up on the mucous membranes of long-nosed dogs, not as much reaches the lungs. Unfortunately, dogs affected with nasal cancer normally do not survive more than 1 year.

Pet birds also may be victims of secondhand smoke. A bird's respiratory system is hypersensitive to any type of pollutant in the air. The most serious consequences of secondhand smoke in birds are pneumonia or lung cancer.