WASHINGTON (AP) - A greater sensitivity of cats to a chemical
found in plastics and pesticides could explain why they've died in
larger numbers than have dogs after eating contaminated pet food,
experts said Saturday.
The small number of confirmed reports of pet deaths bolstered by
a far larger number of unconfirmed anecdotal reports suggests cats
were more susceptible to poisoning by the chemical melamine that
tainted the now recalled pet food, officials with the Food and Drug
Administration and American Society for the Prevention of Cruelty
to Animals said Saturday.
"I am concerned we have a situation where we have a sensitive
species and it is the cat," said Steven Hansen, a veterinary
toxicologist and director of the ASPCA's Animal Poison Control
center in Urbana, Ill.
Testing by the FDA and Cornell University has found melamine in
samples of recalled pet food as well as in crystal form in the
urine and kidney tissue of dead cats. They've also found the
chemical, in apparently raw form in concentrations as high as 6.6
percent, in wheat gluten used as ingredient of the recalled cat and
dog foods, said Stephen Sundlof, the FDA's chief veterinarian.
"There was a sizable amount of melamine. You could see crystals
in the wheat gluten," Sundlof told The Associated Press.
Sundlof and others have not been able to explain why the
chemical would have caused the kidney failure seen so far in the
roughly 16 confirmed pet deaths, all but one in cats. There are
anecdotal reports of hundreds more pet deaths.
"It has a very low toxicity, at least in rodents. The problem
is, we don't have information in cats, and that seems to be the
most susceptible species," Sundlof said of melamine. Sundlof also
allowed that the tainted cat foods could have contained higher
concentrations of melamine than did the dog foods.
Nestle Purina PetCare Co. said Saturday it was recalling all
sizes and varieties of its Alpo Prime Cuts in Gravy wet dog food
with specific date codes. Purina said a limited amount of the food
contained a contaminated wheat gluten from China.
Earlier this month, Menu Foods became the first pet food
manufacturer to recall its products. It did so after cats began to
fall sick and die during routine company taste tests of its
wet-style pet foods, sold under nearly 100 store- and major-label
brands across North America. Other than in the recalled products,
melamine has not been found in other Menu Foods pet foods, the
Melamine is used to make plastic kitchenware, glues,
countertops, fabrics, fertilizers and flame retardants. It also is
both a contaminant and byproduct of several pesticides, including
cyromazine, according to the Environmental Protection Agency.
The United Nations Environment Program considers melamine of low
potential risk, as does the EPA. The agency has sent FDA the
database information it has on the chemical and will provide
technical assistance as needed, EPA spokeswoman Enesta Jones said
Sundlof said the FDA hadn't found any studies of melamine in
cats, and the results of only a single 1945 study that tested it on
dogs. That study suggested the chemical increased urine output when
fed to dogs in large amounts.
"That was pretty much it," Sundlof said.
Still, it's well known that identical substances can have very
different effects on cats and dogs. For example, the flea killer
permethrin is OK to use on dogs but lethal to cats, Hansen said.
The same could be the case with melamine.
"Cats are very sensitive to many different chemicals, whether
drugs, pesticides or plants. We certainly know they have some
unique physiological responses that make them susceptible in cases
where we wouldn't expect it in other species," Hansen said.
The investigation has traced the melamine to wheat gluten that
Menu Foods, Nestle Purina PetCare Co. and Hill's Pet Nutrition
bought from an unnamed U.S. supplier. The latter two companies have
recalled a limited number of products since Friday. The wheat
gluten, a protein source, was imported from China.
Sundlof said the recall could expand further, depending whether
other pet food manufacturers also bought wheat gluten from the same
"We're still in the process of tracing it at this point,"
Sundlof said. There is no indication the wheat gluten entered the
human food supply, he added.
On the Net:
Menu Foods: http://menufoods.com/recall/
(Copyright 2007 by The Associated Press. All Rights Reserved.)