The Chinese wheat gluten imported by ChemNutra Inc. all went to companies that make pet foods, Stephen Miller, chief executive officer of the Las Vegas company, told The Associated Press.
Miller declined to identify what companies ChemNutra supplied. Nearly 100 brands of cat and dog foods made with the ingredient, since found to be chemically contaminated, have been recalled.
The recalled pet food apparently has resulted in kidney failure in animals across the country. The Food and Drug Administration has confirmed 15 pet deaths, and anecdotal reports suggest hundreds of cats and dogs may have died.
Meanwhile, sales are soaring for organic pet food products, which contain only ingredients approved for human consumption, reports CBS News correspondent Nancy Cordes.
"Now suddenly they want to know what's in the foods, what goes in the foods, who makes them and how they're made," says Bruce Ortman, who works at PetHealthStore.
FDA testing of the wheat gluten has revealed it was contaminated with melamine, a chemical with a variety of industrial uses, including the manufacture of plastic kitchenware. As late as Monday, FDA officials had said they were uncertain if the contaminated ingredient had been used in any foods destined for human consumption.
Last week, the FDA blocked wheat gluten imports from the Xuzhou Anying Biologic Technology Development Co. in Wangdien, China, saying it was the source of the contaminated product. The agency had refused to identify who had imported the ingredient, used as a protein source.
"Obviously, if this ingredient was responsible, it's just very upsetting," Miller told AP.
ChemNutra said it has recalled 873 tons of wheat gluten that it shipped to three pet food makers and a single distributor who in turn supplies the pet food industry. The company said the recall applied only to wheat gluten from Xuzhou Anying, one of its three Chinese suppliers of the ingredient.
The importer shipped the product in 25-kilogram paper bags between Nov. 9 and March 8, when it learned the ingredient was suspected as the cause of the pet food problems. ChemNutra said it then quarantined its wheat gluten inventory.
Each bag of wheat gluten included content analysis and test results provided by Xuzhou Anying, ChemNutra said.
"The company is particularly troubled that the certificates of analysis provided by the above-named supplier did not report the presence of melamine," ChemNutra said in a statement.