ALBANY, NY/TORONTO (Reuters) - An ingredient used in rat poison that causes kidney failure in cats and dogs and has been blamed for the deaths of at least 14 animals, was found in samples of Menu Foods cat food, New York State officials said on Friday.
Aminopterin, a folic acid derivative used in rat poison, was discovered in samples obtained from the Ontario-based company, New York State Agriculture Commissioner Patrick Hooker said at a press conference.
Use of aminopterin is forbidden in the U.S. because it can cause cancer and birth defects in humans as well as kidney failure in dogs and cats, the New York Department of Agriculture and Markets said.
"We are pleased that the expertise of our New York State Food Laboratory was able to contribute to identifying the agent that caused numerous illnesses and deaths in dogs and cats across the nation," Hooker said in a release.
Menu Foods is located in Mississauga, Ontario, Canada and has plants in Emporia, Kansas, and Pennsauken, New Jersey, among others.
Executives of Menu told reporters in Toronto on Friday that they will begin testing all suspect raw materials, and that they consider the possibility of tampering to be "remote".
"Some raw material has entered our supply chain that did not meet the quality that had been represented," Menu Foods President Paul Henderson said at a press conference.
On March 16, Menu Foods' brands of its cuts-and-gravy wet pet food -- marketed under a variety of brand names, including Iams, Eukanuba, President's Choice and Nutro Max Gourmet Classics -- were recalled.
The New York State Food Laboratory found 40 parts per million of aminopterin in cat food samples, but were waiting to hear from the U.S. Food and Drug Administration on how safe that level was and if it came from the wheat gluten that was previously suspected of causing illnesses and deaths in pets, Department spokeswoman Jessica Chittenden said.
The FDA said previously that wheat gluten, which is used to thicken the gravy in wet pet food, was the likely cause of contamination.
Menu would not confirm or deny earlier reports that identified wheat gluten from China as the suspect ingredient.
"We'll systematically go through every ingredient and eliminate them as a possibility," said Dr. Richard Shields, Menu's executive vice president. "We don't believe our quality control was lax."
The New York lab obtained the food samples from a toxicologist at the New York Animal Health Diagnostic Center at Cornell University, which has been testing samples to identify the cause of kidney failure in dogs and cats.
The company, which is majority owned by Menu Foods Income Fund, also makes a number of different pet foods sold under private label and store brands at companies including Wal-Mart Stores Inc. and Safeway Inc. and at specialty pet stores like Petsmart Inc.
Menu Foods had said the timing of the complaints coincided with the use of an ingredient from a new supplier, but declined to name the supplier or the ingredient, which it said it has stopped using. The company estimates the recall could cost it up to C$40 million.
Asked about compensation for medical bills of sick pets, Menu Foods' Henderson said "to the extent that we identify that the cause of any expenses incurred are related to the food, Menu will take responsibility for that."
FDA spokeswoman Julie Zawisza said it was investigating the finding by New York authorities. The U.S. agency estimates the recalled products represent 1 percent of all the pet food sold in the United States.
Cornell's College of Veterinary Medicine Dean Donald Smith said the lab would now test wet dog food for the toxin.
Units of Menu Foods Income Fund closed up C$1.20 on the Toronto Stock Exchange, but are still down 32 percent since the recall last Friday.
Additional reporting by Aarthi Sivaraman and Patrick Fitzgibbons in New York; Lisa Richwine in Washington, D.C.; and Susan Olver in Toronto