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  • Writer's pictureStaci-lee Sherwood

Just how safe are pet microchips anyway?

Updated: Apr 10, 2023

By Staci-lee Sherwood

Some of the best pets are rescued animals. They seem to know inherently this is their last chance. Unless you’ve had your pet since their birth their medical/health history is a mystery as is what they may have been exposed to. I’ve had rescued cats for over 20 years and none of them ever had a microchip. Years ago I started researching how effective and safe microchips placed in pets were. I found a lot to be concerned about.

The first thing many don’t know is how likely your pet will be returned if they have a microchip implanted. Not everyone knows to scan a pet for a chip. Having a microchip does not guarantee a pet will be returned. While the industry makes it sounds like a great success, many pets never get returned home regardless of having a chip.

A second thing to consider is that microchips are an electronic device implanted inside the body. There has been much speculation how safe having electronics in your body is. The chips are big business. Most animal shelters won’t even adopt out a dog or cat unless the animal is microchipped first, most veterinarians promote getting them as well. Whenever money is involved it invariably taints decision making for many so it’s best to research the safety issues and draw your own conclusions.

Home Again

In 2013 I adopted a sweet cat a friend had rescued from her neighborhood. Just before Thanksgiving I gave this young female cat a home and named her Sofia. She was a love from the very first day, so grateful to be warm and loved without having to dodge cars and scrounge for food scraps in the dumpster.

Sofia was lucky she found a home. I thought she was about 2-3 years of age and seemed in good health. She thrived and was very happy to have a home and share it with another of my rescue cats. Then in 2019 she got sick. I knew she had been an abandoned pet and then discovered she had a microchip. .

A lump was felt and discovered she had a cancerous tumor around the Home Again microchip. She is not the first and won’t be the last animal to get cancer from microchips. One has to wonder why people think it’s safe to put electronics into a living body? The science is way too new to accurately show all side effects, especially long term. We know rejection of organ transplants can run high so imagine how the body relates to a foreign object.

Sofia was lucky to be a well loved well cared for indoor cat not exposed to smoke or pesticides. Her exposure to other toxins is about nil. The first biopsy came with removal of the microchip. We didn’t know she had cancer we just wanted the microchip removed when a lump was felt. The biopsy showed cancer so a week later a second surgery was done and thankfully that result showed all cancer to have been removed. She was lucky, many pets are not.

Sofia’s biopsy report confirming cancer tumor around Home Again microchip

Pet care is big business and microchips are sold by most veterinarians and even rescues. The public thinks it’s a safe simple way to ensure your pet is returned home but side effects are rarely explained. The lawsuits and studies showing animals getting cancer from them are downplayed leaving pet owners in the dark.

When money is involved question everything you’re told and everyone telling you.

Merck & Co.

Merck is one of the largest pharmaceutical companies in the world. In 2021, it raked in over $48 billion in revenues. They are the parent company of Home Again pet microchips. With an unlimited client base of animals in shelters, rescues, stores and breeders, Big Pharma giant Merck and their subsidiary Home Again make millions in sales. Most shelters won’t release a dog or cat without first implanting a microchip that is included in the cost of adoption. The dangers are not told to potential pet owners. I spent years working in and with dozens of shelters and rescues both in New York and Indiana and know this to be true. Heavy marketing was done to insure those involved with animals, including veterinarians and animal hospitals, were all on board with pushing microchips.

Studies Studies Studies

If you Google ‘microchips studies’ or ‘microchip lawsuits’ many listings come up. I encourage anyone thinking of chipping their pet to read through at least some of them. You will see there are many dangers and side effects not being told to pet owners.

This site provides a lot of good information showing how the public has been misled for years by the pharma industry cashing in by playing the sympathy card. Everyone wants a lost pet to be returned but at what cost are people willing to risk their health and lifespan?

Years of research and studies show claims of total safety are, at the very least, over exaggerated. ‘In at least six studies published in toxicology and pathology journals between 1996 and 2006, researchers found a causal link between implanted microchip transponders and cancer in laboratory mice and rats. The tumors were typically sarcomas, including fibrosarcomas. In almost all cases, the tumors arose at the site of the implants and grew to surround and fully encase the devices. In several cases the tumors also metastasized or spread to other parts of the animals’. Rate of cancer ranged from 1 – 10 % but researchers acknowledged it could actually be higher since focus was on seen tumors and not microscopic tumors easily missed. Click here to read more about these studies.

Many of these studies were not conducted in the United States so unless you’re involved in the animal health industry would not have knowledge of these. The animals involved range from cats, dogs, mice and rats to fruit bats, marmosets and even alpacas. Click here to peruse more than two dozen studies on the connection between microchips and cancer.

A study from 1997 ‘Subcutaneous soft tissue tumours at the site of implanted microchips in mice’. Click here to read more

Another study conducted in 2001 ‘Tumors in long-term rat studies associated with microchip animal identification devices’ found that ‘Tumors surrounding implanted microchip animal identification devices were noted in two separate chronic toxicity/oncogenicity studies using F344 rats.‘ Click here to read more

A study of tumors and microchips from 2007 ‘Fifty-two subcutaneous tumours associated with microchip were collected from three carcinogenicity B6C3F1 mice studies.’ Click here to read more

It’s safe to say none of these studies are widely known to the consumer of these devices. One cannot make a good decision without accurate information. It’s clear all the necessary data is being concealed by the drug companies who stand to make millions.

With so many questions about the safety of microchips, shouldn’t there be more scrutiny about their use? Isn’t your pet’s health important enough to question what you’re told? Our pets can’t speak for themselves, they can’t tell us if they’re sick. By the time we see the chip has made them sick it’s often too late to help them. If you wouldn’t implant a microchip in your body why would you do that to your pet’s? Research everything you can before agreeing to use them, your pet’s life might just depend on the choice you make for them.

Money is likely the real driver

When a lot of money is involved the truth often takes a backseat. To put in perspective how much money microchips generate consider these numbers. There are approximately 69 million pet dogs and 45 million pet cats for a total of about 114 million pets. On average microchips cost $25 though the range can be from $10 – 75. It’s thought that less than 10% of pets are micro chipped but since many owners never register them it’s impossible to get truly accurate numbers.

If only 10% of pets are chipped that’s 11.4 million pets bringing in over $114 million dollars and likely more. It’s easy to see why so many push their use and make outlandish and false claims that they are completely safe or come with little to no side effects. When big money is involved people make bad decisions and hide anything that will interfere with profit. Your pet depends on you making informed decisions so think twice before you chip your pet.

Your pet can’t speak for themselves so it’s up to us pet parents to look out for them as we would want someone to look out for us.

Also published on The Good Men Project on April 10, 2023

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Sonya Perley
Sonya Perley

Thank you for this article. It took me a long time to scroll through all the other articles that were in favor of microchipping animals. Finally, I found yours after persisting in this search, as my instincts told me this probably wasn't a healthy choice for my little cat. I felt they are hiding this information.


McKenna Grace Fisher
McKenna Grace Fisher

~ Such an important read sister ~ Thank you and I hope many more learn of this ~ Very ad but needs to be known and addressed by Vets ~ xx

Staci-lee Sherwood
Staci-lee Sherwood

Amazing how information that used to be online is now gone this is happening more often...wonder why?

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