There has been recent widespread news coverage about the perceived danger of microchips causing cancer in pets. Veterinary experts, including cancer specialists, dispute this concern, saying that there is no evidence that microchips cause cancer in our pets.

The studies that caused the concern dated from the mid-1990s, and showed that microchip implants had induced tumors in some laboratory mice and rats. A case report documenting the death of a dog due to a subcutaneous cancerous mass was also mentioned in the press, since this dog also had a microchip.

When this issue first received publicity in January, groups that advocate microchips in pets as a means of identification reviewed the research studies that prompted the concerns.  They concluded that the studies were flawed – the particular strain of mice that was used in the research is predisposed to cancer, and thus does not represent the population of pet animals that are usually microchipped.  They also concluded that it was inappropriate to conclude that there was any cause and effect association between the microchip and the tumor in the case report. 

Millions of animals now have microchip identification, owing in part to the routine practice of implanting microchips in all dogs and cats that are adopted from humane societies, animal shelters, and many animal rescue organizations. Indeed, it is estimated that about 8,000 pets per month are returned to their owners in the United States alone, because of microchip identification.

The American Veterinary Medical Association, the Canadian Veterinary Medical Association, and groups such as the Coalition for Reuniting Pets and Families currently endorse microchip technology for pet identification. The Veterinary Cancer Society and American College of Veterinary Pathologists are aware of the controversy, as are veterinary oncologists and pathologists. No clinical studies are possible at this time because of the lack of cases.

All of these groups will remain vigilant to this concern, but agree that the benefits of microchipping far outweigh any concerns that have been raised to date. At this time, the FDA remains firm in its approval of microchipping for pet animals, and veterinarians continue to recommend this form of identification.

The fall is the time for homeowners to perform routine maintenance jobs around the house, especially on the exterior. Driveways may get re-sealed or paved with asphalt, exterior windows and doors may receive a new application of caulking, expandable foam insulation may be used to seal up cracks or crevices, and a fresh coat of paint may be applied to trim or siding.  Gardens and lawns may be treated with fertilizer or pesticides, or a fresh layer of mulch may be added to flower beds or around trees.  Do It Yourself fans may perform maintenance tasks such as fluid changes on their vehicles, including cars, lawn tractors, and snow blowers.

All of these activities can cause potential injury to the family pet, or to animals that are roaming in the neighborhood. If an animal walks through or brushes against substances such as fresh tar or driveway sealer, caulking, paint, or pesticide, the material may get stuck to its fur or skin, or even be absorbed through the skin into the body. The natural response to a pet that has something stuck to its skin or fur is to lick or chew the affected area to remove the substance. This presents a risk if the material is toxic or caustic.

Dogs, and especially puppies, like to chew things that they find lying around. There has been a rise in illnesses associated with puppies that have chewed open containers of expanding foam and swallowed the pre-expanded product. Once it reaches the stomach, the material expands, causing a life-threatening obstruction that requires immediate surgery.

Chemical fertilizers can be poisonous, while some pesticides are not only toxic but also irritating to skin. Some types of mulch, particularly that made from cocoa bean husks, are toxic to animals – cocoa bean mulch smells appealing and contains the same toxins that are found in chocolate, representing a significant threat to the family pet.

Fluids that are used in machinery or cars can be toxic – used fluids may be toxic due to the presence of contaminants or byproducts of combustion, while fluids such as radiator antifreeze contain ethylene glycol, which causes kidney failure, but tastes good!

Home treatment of the pet can pose additional risks. Well-meaning friends or acquaintances may recommend using solvents such as paint thinner to remove paint or tar from your pet's coat or feet. While this sort of treatment may be okay to use on an adult person, you should always remember that pets lick themselves! Thus, anything that has a poison label on the container, or a warning not to take the product internally, should NEVER be used on an animal's skin or fur. Animals have become seriously ill from ingestion of solvents such as mineral spirits, paint thinner, turpentine, lubricant sprays, rust removal sprays, etc. If you do need to remove oil-based materials such as tar or paint, or sticky substances such as tree sap, a better choice is to use something that is relatively benign, such as mineral oil. Better yet, call our clinic for specific advice as to what to use. And, if you are concerned that your pet may have been exposed to one of these hazardous materials, you should seek advice sooner rather than later.