Australia will no longer offer importers the option of irradiating imported cat food to reduce microbial hazards following reports of a possible link between irradiated food and neurologic damage in cats.
In November 2008, Dr. Georgina Child of the University of Sydney reported finding an association between Orijen cat food from Canada and neurologic damage in Australian cats, according to the Sydney Morning Herald.
Orijen's manufacturer, Champion Petfoods, recalled the cat food in Australia. Champion, which exports Orijen to dozens of countries, indicated that Australia is the only one that requires importers of Orijen to irradiate the food because Champion does not wish to subject the food to heat treatment.
The Australian Quarantine and Inspection Service issued a notice in December stating that many studies have found food irradiation to be safe, although irradiation can reduce vitamin content. Australia offers gamma irradiation or heat treatment as options for importers of pet food that manufacturers have not cooked at high temperatures.
In March, AQIS released an update stating that it had become aware of scientific literature questioning the safety of irradiated pet food. One study, "Leukoencephalomyelopathy in specific pathogen-free cats," in the November 2007 issue of Veterinary Pathology, suggested an association between gamma-irradiated food and leukoencephalomyelopathy cases in an SPF cat colony in Ireland. A cause-and-effect relationship was not established, however.
Biosecurity Australia, after considering available information, advised AQIS that it no longer considers gamma irradiation to be a suitable treatment for imported cat food. In June, AQIS issued a notice that it will withdraw the option for imported cat food but not imported dog food.
The U.S. Food and Drug Administration has approved irradiation for several types of food, including pet food, but the process is not in widespread use in this country.