By Dan Knox, DVM*
There have been some comments questioning the safety of microchips. Several articles referencing foreign studies have been quoted in various formats. In literally millions of American dogs, cats, horses and other pets that have been microchipped and protected over the past 20 years, there have been no sarcomas reported as a direct result of a microchip. A more common associated observation would be an immunization reaction from concurrent vaccinations or other trauma in the same anatomical area as a microchip implantation. It is possible to physically inject a piece of hair or surface contaminant with the implantation. The foreign reports are unclear on a number of issues including techniques, sterility and procedures; therefore, such reports may be brought into question.
- Dr. Dennis Macy of the University of Colorado, School of Veterinary medicine states that microchips did not cause lesions in animals he studied.
- Rao and Edmonton from the National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (Toxicol Pathol, 1990;18(3):412-6) Reported a two-year study in 1990 with 70 animals having no noplastic changes observed following microchipping.
- JAVMA, June 1, 2005, Vol226, No 11. Vaccine Associated Feline Sarcoma Task Force Roundtable Discussion, in answer to question #3 of this discussion, microchips were not seen as a cause of sarcomas. source
- JAVMA, Nov 1, 2003, Vol 223, No 9. pp 1316-1319. Evaluation of microchip migration in horses, donkeys and mules. Addressed the microchip migration question in horses. Neither migration of the microchip nor microchip associated sarcomas were reported. source
- The fact that rats and mice are prone to skin tumors and are bred for this purpose complicate the scientific evaluation of such reports. Please contact the author if there are additional questions or information needs.
* Director, Companion Animal Operations
AVID Identifications Systems, Inc. 314-660-2843 Dan.Knox@avidid.com