As an already extensive list of tainted pet foods continued to grow, the U.S. Food and Drug Administration in May determined that wheat flour mislabeled as wheat gluten and rice protein was the true problem leading to the largest pet food recall in U.S. history.

Investigators believe melamine was added intentionally to wheat flour imported into the United States from China, making its protein levels consistent with those of wheat gluten, according to Dr. David Acheson, FDA’s new assistant commissioner for food protection. However, this discovery did not change recent pet food recalls.

On May 2, Menu Foods Inc. (Streetsville, Ontario) expanded its recall to include “cuts and gravy”-style foods and select other products made at any of its U.S. or Canadian plants during the period that the suspect wheat gluten was used due to the possibility of cross-contamination. (For an updated list of recalled Menu Foods products, visit www.menufoods.com.)

Melamine-related recalls by a growing list of ingredient suppliers and contract manufacturers have prompted leading manufacturers to issue recalls of their own. Royal Canin USA (St. Charles, Mo.) expanded its previous recall to include eight Sensible Choice dry dog foods and seven Kasco dry dog and cat foods with date codes between July 28, 2006, and April 30, 2007. Sensible Choice formulas include Chicken and Rice Adult, Chicken and Rice Reduced, Lamb and Rice Reduced, Chicken and Rice Puppy, Chicken and Rice Large Breed Puppy, Natural Blend Adult, Natural Blend Senior and Natural Blend Puppy dry dog foods. Kasco formulas include Chunks, Hi Energy, Maintenance, Mealettes, Mini Chunks and Puppy dry dog foods, and Cat dry cat food.

Blue Buffalo Co. Ltd. (Wilton, Conn.) expanded its initial recall to include all Blue brand canned dog food and treats, and all Blue Spa Select canned cat food because its contract manufacturer, American Nutrition Inc. (Ogden, Utah), added tainted rice protein concentrate without the company’s consent.

For a similar reason, Sierra Pet Products L.L.C. (Wilton, Conn.) recalled all canned dog and cat foods and all dog treats sold under the Harmony Farms brand, and Canine Caviar Pet Foods Inc. (Anaheim, Calif.) recalled 13.2-ounce cans of Gourmet Turkey and 13.2- and 5.5-ounce cans of Gourmet Beaver formulas for dogs.

Other companies that recalled products produced by American Nutrition included Natural Balance Pet Foods Inc. (Pacoima, Calif.), which recalled 13-ounce cans of its chicken, beef and lamb formulas for dogs, and 3- and 6-ounce cans of its ocean fish formula for cats. Diamond Pet Foods (Meta, Mo.) recalled 13-ounce cans of Diamond Lamb & Rice Formula for Dogs and Chicken Soup for the Pet Lover’s Soul Puppy Formula, and 5.5-ounce cans of Chicken Soup for the Pet Lover’s Soul Kitten Formula.

Contract manufacturer Chenango Valley Pet Foods (Allentown, Pa.) also recalled products containing tainted rice protein concentrate, including several dry dog and cat foods with Doctors Foster & Smith labels, 4- and 18-pound sizes of Lick Your Chops Kitten & Cat dry food with date code “Best Used by April 29, 2008”; bulk Chicken & Brown Rice Formula Adult Lite shipped to SmartPak (Plymouth, Mass.) on Feb. 9 as well as bulk Lamb & Brown Rice Formula dry dog foods with date code Feb 9, 2008; 25-pound sizes of Shop Rite Redi-Mixt dry dog food with date code C7107; 20-pound size of Shep chunk-style dry dog food with date code “Best Used by March 14, 2008”; 1-kilogram/4-pound, 4-kilogram/8.8-pound and 8-kilogram/17.6-pound sizes of Health Diet Chicken & Rice Dinner dry cat food with date code C7072; and 7-pound size of Evolve Kitten Formula dry food with date code “Best Used by Sept. 13, 2008.” Chenango Valley also recalled one dry food for ferrets—the 20-pound size of 8 in 1 Ferret Ultra-Blend Advanced Nutrition Diet with date code C7072.

In conjunction with the Chenango Valley recalls, SmartPak recalled all lots of LiveSmart Adult Lamb and Brown Rice dog food. Sold in portion-packs shipped directly to consumers, the food contains neither wheat gluten nor rice protein concentrate but likely was cross-contaminated at the Chenango Valley plant.

(For recall updates, visit fda.gov/oc/opacom/hottopics/petfood.html.)

Although the melamine contaminant entered the human food supply through tainted pet food scraps fed to hogs and chickens across the country, testing by the FDA, the U.S. Department of Agriculture, the Centers for Disease Control and Prevention, the Environmental Protection Agency and the Department of Homeland Security found very low risk to human health associated with consuming meat from these animals.

On the legislative front, the U.S. Senate on May 2 approved legislation introduced by Sen. Richard Durbin (D-Ill.) and Rep. Rosa DeLauro (D-Conn.) that would require the FDA to set processing and ingredient standards for pet food, strengthen labeling requirements, establish an early warning system for contaminated food products, improve communication with the public and veterinarians during recalls, and take other steps to prevent deaths and illness.

Durbin’s actions garnered praise from The Humane Society of the United States (Washington). “The Humane Society of the United States commends Sen. Durbin for his fast action to protect the food supply for people and their pets,” said Wayne Pacelle, president and chief executive officer for HSUS. “The last six weeks have exposed that the safety standards for pet foods are not in place in any significant way, and the constant drumbeat, day after day, of recalls has shaken consumers’ confidence in the pet food industry’s adherence to food safety standards.”

Based on input from more than 1,300 pet food industry executives at its annual Petfood Forum and Petfood Forum Europe conferences—held April 16-19 in Chicago and May 6 in Utrecht, Netherlands, respectively—Petfood Industry magazine, published by Watt Publishing (Mount Morris, Ill.), announced its intention to form a Petfood Industry Advisory Board. At press time, organizers were finalizing goals and objectives for the group.

As the fallout continued, makers of pet foods touted as human-grade, organic and all-natural reassured consumers of their foods’ safety. For example, Natura Pet Products Inc. (San Jose, Calif.), maker of Innova, Evo, California Natural, Healthwise, Karma and Mother Nature brands, in May announced that an independent laboratory will continually test all of its ingredients and finished products to guarantee they are melamine-free.

“Natura Pet Products has incorporated melamine testing as a standard part of our expanded, 120-point ingredient quality-control program. This means that all Natura pet foods will be tested and confirmed to be melamine-free before being released,” said Peter Atkins, president of Natura, in a message to the company’s customers.