Skip to content 
At face value, it seems like a great idea to have your dog microchipped in case they were to ever get loose and lost.
There is no worse sinking feeling than finding your gate or front door ajar while you were out and having no idea where your furry family member has gone.
As you search the neighborhood frantically, it would seem like having a microchip could be the answer to your prayers.
But it turns out, there are factors to consider when deciding if a microchip is best for you and in the best interest of your pet.
Veterinarians and microchip manufacturers downplay the idea of a significant risk of tumors at the microchip site.
They say adverse reactions are rare. But the problem is, there is no requirement to report adverse reactions.
We simply have not had enough data regarding microchipping. There is no compulsion to report in the US.
But in the UK, where microchipping became mandatory in 2016, we are now getting a look at such data.
While the numbers may still be low, it should be noted that there is in fact a health risk involved.
Rare cases have been reported of an animal’s behavior changing once the microchip has been implanted.
There are also reports of rejected chips (especially in cats and small dogs), registration problems, improper implanted chips and worst of all … the microchip traveling to other parts of the body … in some cases traveling to the stomach of the animal.
The biggest fear of course for most pet parents is the chance that a dog will develop a tumor as a result of the microchip.
It would stand to reason that a foreign object being injected into the body would cause a cancer forming response around said object.
Not unlike what has been documented as cancerous tumors forming at the injection site of vaccinations, there are reports coming out of tumors at the implant area of the microchip, actually forming around the chip itself.
Microchip tests on mice and rats showed a 1 to 10 percent chance of developing “aggressive and lethal microchip induced cancerous growths.”
In 2010, Merck was served with a lawsuit over claims that its HomeAgain microchip caused cancer in a Massachusetts cat named Bulkin.
This has prompted another look into the practice of microchipping and there are staunch animal advocates who are sounding the alarm.
One such advocate is Harvard graduate, Dr Katherine Albrecht, the founder of ChipMeNot.
Traveling Microchips and tumors
The following are some excerpts from her website:
“Based on the alarming number of microchip-linked cancers we’re discovering, I predict this lawsuit will be just the tip of the iceberg,” said Dr. Katherine Albrecht, a consumer advocate and expert on adverse reactions associated with
implantable microchips.”
“Microchips consist of electronic components encased in bio-compatible glass. These are the chips most commonly displayed. However, manufacturers have added polymers to bond (interact) with the tissues of the animal to prevent migration. These polymers can contain all kinds of toxins as impurities that migrate to the surface over time. Bio-bond is a porous polypropylene. Datamars has introduced an entirely polymer encapsulated pet microchip with an undisclosed composition. Their patent suggests it is a silicon filled polyester. Parylene C (AKA chlorinated poly-dimethybenzene) has also become a coating for pet microchips, with no cancer studies available.”
“When a microchip is implanted in a cat or dog they suffer pain through acute inflammation for around three days. The inflammatory response continues for approximately a month until the implant is covered with scar tissue so animals need care and considerations for some time after implant. Implant techniques into the pets tissues and plastic coatings are intentionally designed to be inflammatory, to cause the inflammatory response that covers the microchip with scar tissue. The American Veterinary Medical Association (AVMA) sites an independent study on beagles where only 87 of 90 implants formed the scar tissue. So what happens with the inflammatory response when no scar tissue forms? Does it never start or never stop? So how much does the microchip implant increase the level of inflammation in a pet?”
“The plastics used as sleeves or to coat or encapsulate microchips can contain toxins that migrate to the surface over time, releasing into the pet. Parylene C is chlorinated poly-dimethybenzene and so benzene would be incorporated into the polymer chain. One should consider the ways that benzene causes cancer when considering the safety of the polymer as well as any impurities in parylene C. Promoters will tell you it is safe, that it is inert. Being inert is also one of the outstanding characteristics of Benzene.”
“Claims that pet microchips are passive, activating only when scanned may be in part true about the actual microchip but the implant also has an antenna. The antenna is not a selective receiver and can intercept, generate current with, and re-radiate other electromagnetic waves in the environment. If the wave received by the antenna is tuned out before the microchip, it is simply re-radiated. Electromagnetic waves in our environment are of health concerns as they can cause oxidative stress to our cells . Implanting a microchip, that has an antenna, in a pet would need to be considered as to having an adverse effect on their health.”
Another resource for overall dog health is Dogs Naturally Magazine. Here is an excerpt from their article on microchips:
Should You Microchip Your Dog? – Dogs Naturally (dogsnaturallymagazine.com)
“When tumors were removed, chips were found embedded within some of the tumors. Animals have experienced
neurological damage as a result of microchips. Animals have also died due to the microchip implant procedure. A microchip was discovered in the brain stem of a kitten who died immediately. A young Chihuahua died within hours of being chipped, from excessive bleeding at the injection site.”
Safer alternatives to microchipping
On the other end of the spectrum, proponents of microchipping, use the rodent studies to prove the link of microchips to malignant tumors is small.
Does the fact that millions of dogs have microchips, yet we haven’t seen an epidemic of microchip-related cancer, confirm
that the percentage is small?
Or does it simply mean that the correlation has been overlooked because most dogs and cats are cremated versus having a necropsy done for cause of death and there is no compulsory to report as a microchip is categorized as a medical device which does not prompt such reporting?
As any dog lover knows, statistics mean nothing when your pet is the one affected. I am not sure about you, but I really don’t want a 10% higher chance that my pup will get cancer.
No form of identification is flawless and none of them is guaranteed to bring your pup home.
It’s up to you to weigh the risks and benefits and decide what is best for your pet.
But know that there are safer methods of locating a lost pet especially with Apps like Next Door and Pet Finder.
Not to mention there are now tags with GPS or information tattoos, among other options.
These definitely seem like more viable options than injecting a piece of metal and plastic into your dog’s body and hoping that it doesn’t deprive you of additional years with them.
