Tails of Seattle: A pets blog
Veterinary Q&A: Secondhand smoke and our pets
Dr. Clare Knottenbelt is a professor at the College of Medical, Veterinary and Life Sciences at the University of Glasgow, Scotland, where her recent research involves assessing hair nicotine in dogs exposed to secondhand smoke. She answers this week's questions.
Question: What role does secondhand smoke play in a pet's health?
Answer: It has been difficult to prove many associations with secondhand smoke (SHS) in pets because we can't ask the pet themselves. However, we know it can increase the risk of some cancers.
In addition, the smoke sticks to the pets' hair, which means when they groom themselves the smoke will be eaten as well as breathed.
As vets, we can tell when an owner smokes because their pet smells strongly of stale smoke. I met one owner who realized the effect that smoking was having on her cat when she found the cats bed was stained with nicotine.
Question: What specific problems have arisen from secondhand smoke? How serious can they be?
Answer: We know that SHS exposure increases the risk of nose and lung cancers in dogs and lymphoma (cancer of the white blood cells) in cats. It also may have a role in mouth cancer in cats and changes the cells in the lungs of dogs.
In cats, lymphoma has a poor prognosis, with cats rarely surviving more than six months even with aggressive chemotherapy. Nasal cancer in dogs requires radiation therapy and even then the cancer is likely to recur.
Question: Do pets face the same kinds of problems as humans who are exposed to SHS or are they worse? Is lung cancer or respiratory problems a big issue?
Answer: Dogs and cats do not get the kind of heart disease that humans get; however, cats are prone to asthma and dogs are prone to allergic skin disease.
Lung cancer is relatively uncommon in cats and dogs, but we do know that in dogs the incidences increase when an owner smokes.
Question: Are some breeds more vulnerable than others?
Answer: Not really, although smaller dogs may be bathed more frequently than larger breeds. This might affect how much smoke remains on their coats and was, therefore, able to be ingested.
Question: What kind of monitoring should a veterinarian do to determine if SHS is affecting his/her patient?
Answer: I think the most important thing a vet can do is to ask the owner about SHS exposure when performing routine health checks. Owners can reduce the effect on their pet by only smoking outdoors or, of course, by giving up completely.
Owners tend not to think about the effect that they habit is having on their pet, so it is the vet's responsibility to ensure that the pet has the fresh air it deserves. This should be routine for all pets, but every vet knows that you can smell a pet whose owner smokes as soon as it enters the room and that is a sign that exposure is significant.
Question: You are now studying nicotine levels in the hair of dogs. Can you generally tell us how many animals are involved and what you are finding?
Answer: My study, which is being presented at the World Small Animal Veterinary Association (WSAVA) conference in Birmingham, England, next April, used hair from 38 dogs. We found that the levels of nicotine in dogs exposed to SHS were similar to those found in children in smoking homes.
Reducing the amount of exposure by smoking outdoors significantly reduced the amount of nicotine in the hair and is a valuable way of reducing exposure to the toxins in cigarette smoke.
Dr. Clare Knottenbelt
Knottenbelt is a professor of small-animal medicine and oncology, clinical director of the small-animal hospital and head of small-animal clinical sciences at the School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, at the University of Glasgow in Scotland. She graduated from The University of Bristol in 1994. Her major areas of interest are the prevention and treatment of cancer in domestic pets.
Read our past Q&As:
Veterinary Q&A: Liver disease
Veterinary Q&A: Human meds can be toxic for pets
Veterinary Q&A: Food allergies
Veterinary Q&A: Follow-up on toxins -- aloe vera
Veterinary Q&A: Common toxins for pets
Veterinary Q&A: Dogs with dry, itchy skin
Veterinary Q&A: Ways to stop stool eating
Veterinary Q&A: Holiday toxins that can hurt your pets
Veterinary Q&A: Itchy skin and hair loss in cats.
Veterinary Q&A: Pancreatitis
Veterinary Q&A: Dementia and senior dogs
Veterinary Q&A: More health issues facing aging dogs
Veterinary Q&A: Eye problems in aging dogs
Veterinary Q&A: Halloween treats and pets
Veterinary Q&A: Health issues facing aging dogs
Veterinary Q&A: Why blood work is necessary
Veterinary Q&A: Are prong collars safe for your dog?
Veterinary Q&A: Birth control for pets
Veterinary Q&A: How to find a good vet
Veterinary Q&A: Neutering your dog Part 2
Veterinary Q&A: Neutering your dog Part 1
Veterinary Q&A: Hyperthyroidism in cats
Veterinary Q&A: Incontinence in dogs
Veterinary Q&A: Hanging tongue syndrome
Veterinary Q&A: Bad breath in dogs
Veterinary Q&A: How much is too much exercise for my dog? Part 2
Veterinary Q&A: How much exercise does my dog need? Part I
Veterinary Q&A: A killer called bloat
Veterinary Q&A: Initial care for new puppies
Veterinary Q&A: Knee problems in dogs
Veterinary Q&A: Flea-control treatment
Veterinary Q&A: Bearded dragon lizards
Veterinary Q&A: Vaccinations for indoor cats
Veterinary Q&A: Lumps and bumps
Veterinary Q&A: More on aging dogs and arthritis
Veterinary Q&A: Aging dogs and arthritis
Veterinary Q&A: Puppy and geriatric exams
Veterinary QA: What dogs can safely chew
Veterinary QA: Why does it cost so much to clean a dog's teeth?
Veterinary QA follow-up: More on cleaning a dog's teeth
Veterinary QA: When to spay or neuter
Do you have a question about pet health? Ask now! We'll pose some of your questions to a local vet in an upcoming post.