Medicine: Secondhand Smoke

In response to numerous questions on whether or not secondhand smoke affects our pets, I’ve done a little research into the subject.

The effect of secondhand smoke on people is a fiercely debated subject. The effects on our pets are debated no less. There are no direct studies on the effects on animals. All of the data is interpreted from human studies or are epidemiological. This means a retrospective study based on numbers of affected animals.

Although we see asthmatic cats with no history of smoke exposure, there is plenty of anecdotal evidence that secondhand smoke certainly can be a huge factor in causing asthma in cats. It is unknown if licking the ash of the fur or direct inhalation is the cause. Asthma can be a life-threatening emergency in cats. Certainly, we see many cats with asthma and no smoke exposure.

Birds can also be very sensitive to smoke. There was at least one case documented of a parrot that lived in a smoky bar that died of primary lung tumor (which is very rare in birds). One case, of course, doesn’t establish causality.

In a recently published study in the American Journal of Epidemiology, the Tuft’s Veterinary School did a retrospective study on cats presented for lymphoma, a type of cancer common in cats. 180 cats were involved in the study between 1993 and 2000. Cats with one smoker in the family were found to have twice the likelihood of developing lymphoma than those in a smoke-free environment. Cats with two smokers had four times the likelihood. Cats with smokers who lived indoors were much higher than those two lived outdoors.

A study of nasal cancer in dogs published in the American Journal of Epidemiology found an increase in cases with exposure to tobacco smoke especially in long-nosed dogs.

Unfortunately, we don’t have as much clear evidence as we’d like, both for people, and for pets. I certainly think that inhaling smoke is not a healthy thing for our bodies, and certainly not good for our pets. If you must smoke, please limit the exposure to your pets and children. Smoke outdoors, away from your pet’s environment. Wash your hands and face before playing/touching/feeding your pets. Change your clothes before picking them up or getting into their environment, such as a dog bed, their favorite couch, etc. Never smoke in a confined space with a pet, such as the car. Doing these things can only help to prevent any problems associated with smoking.