A tiny piece of technology about the size of a grain of rice is responsible for reuniting thousands of pets with their families all across the country.
Now that studies are suggesting the microchips may cause cancer, animal rescue officials in Snohomish County worry some pet owners may turn their backs on the technology.
The series of studies, which date back to the mid-1990s, question whether chip manufacturers and federal regulators ignored or overlooked studies about whether microchips or the process of injecting them might cause cancer in dogs or laboratory rodents.
Microchip technology for pets is widely used in Snohomish County.
Thousands of animals are implanted with microchips each year before they’re adopted out to new families from two regional animal rescues, the Northwest Organization for Animal Help in Stanwood and the Progressive Animal Welfare Society in Lynnwood.
Some communities such as Mill Creek offer residents free or discounted pet-chipping services.
Liz Helmer, the lead veterinarian at the Progressive Animal Welfare Society, said inflammation from any kind of shot or implant has the potential to cause cancerous tumors. However, the microchips themselves are not dangerous, she said.
“My dogs are chipped,” Helmer said. “I’m a veterinarian and a hysterical dog owner, and I wouldn’t do anything I thought was a risk for them.”
To Celeste Bishop, a Snohomish farmer, the concern over cancer is another reason why the government should not require animals to be microchipped. She said chips can also dislodge, move beneath the skin and cause infection.
She is against a voluntary federal program that encourages farmers to implant microchips in their livestock.
“The goal is to force me to chip my animals,” Bishop said. “Now, if they cause cancer, what do you do?”
Bishop worked with Rep. Kirk Pearson, R-Sedro Woolley, earlier this year to introduce a bill seeking to prohibit the state from taking part in an animal identification system. The bill was not approved.
Microchips are usually injected in the skin between the shoulder blades of cats and dogs. The chip has no power supply, battery or moving parts and has an operating life of more than 25 years, according to the Web site of AVID Microchip ID Systems, a brand used by local animal shelters.
Each chip has its own code, which is readable with a handheld scanner. By entering the code into a database, animal shelters, veterinarians and police can instantly access an animal’s complete medical and residential history.
It’s far riskier to leave pets unchipped, Helmer said.
In Washington, roughly 66,000 animals are euthanized in shelters each year. Many of those animals are strays without microchips or identification tags. Only 10 percent of dogs and 1 percent of cats are chipped, Helmer said.
Animal health experts say the health risk associated with microchips is minimal.
“I can tell you so many anecdotes of pets being reunited with their owners,” said Susanne Boskovich, operations manager at N.O.A.H. “I think that should alleviate any concerns the public has.”
The Morris Animal Foundation, which is in the midst of a $30 million campaign to study canine cancer, channels funding to scientists and research groups for studying cancer in animals.
The foundation has never had a request from anyone wanting to examine the relationship between microchips and cancer, said Heidi Jeter, the foundation’s director of communications.
Microchip manufacturer VeriChip Corp. responded to a recent Associated Press report about the microchip controversy by saying the article cited no controlled scientific studies linking the chips to cancer in dogs or cats. Also, lab rodents are more prone than humans or other animals to developing tumors from all types of injections, the manufacturer said.
Dan Knox, director of Companion Animal Operations with Avid Microchip ID Systems, said other studies using laboratory mice have shown no link between cancer and microchips. The biggest risk of implanting a microchip isn’t cancer, but accidentally injecting a hair, dirt or bacteria into an animal, he said.
“Microchips save an untold number of animals’ lives each year, and I think people should certainly be aware of this story and not use this as a reason not to do it,” Knox said.
Rick Bell of Oak Harbor, whose family has raised and shown purebred dogs and horses for years, said none of his animals has ever suffered from a health problem caused by microchips. He’s never heard of chips causing cancer, either.
“Personally, I don’t believe it,” said Bell, a radio station engineer. “There’s nothing in the chip. There’s nothing radioactive, there’s no power to it, no battery or anything.
“From a user standpoint, we don’t even think twice about it.”
Reporter Scott Pesznecker: 425-339-3436 or firstname.lastname@example.org.