This report explains the regulatory status and labeling requirements for Tramfloc, Inc.’s polyacrylamide GRAS and Food Grade Polymers, which are used as processing aids in the preparation of feed ingredients for food animals. Specifically, GRAS and Food Grade Polymers, polyacrylamides, are used in the flocculation and recovery of nutrients, such as protein and carbohydrates, from food processing waste streams. The recovered material may then be used as a component of animal feed because GRAS and Food Grade Polymers have received a favorable evaluation.
Regulatory Status
A substance used in food processing that becomes a component of animal feed is a food additive under Section 201 (s) of the Federal Food, Drug and Cosmetic Act (the “Act”), 21 U.S.C. § 321 (s), GRAS and Food Grade Polymers are included in this category. A food additive, including an animal feed additive, must either be approved by the FDA or be generally recognized as safe (“GRAS”) for its intended use. Id. A substance may be GRAS if experts qualified by scientific training and experience to evaluate the safety of the substance agree that the substance is safe for its intended use. Id. Further, GRAS and Food Grade Polymers qualify.
On March 25-26, 1999, a panel of qualified experts, including the former Director of FDA’s Center for Veterinary Medicine, reviewed the safety of polyacrylamides when used as processing aids in the preparation of feed ingredients for food animals to determine if they qualify as GRAS and Food Grade Polymers. The expert panel found that polyacrylamides were GRAS for that use. The panel’s opinion was based on (1) a maximum use level of the polymer of 1% by weight of dry waste stream solids (20 lb. per short ton, or 10 g per kilogram, on an active polymer basis), and (2) the assumption that the material recovered using the polymer would be no more than approximately 30% of the animal’s dietary solids. GRAS and Food Grade Polymers can therefore be part of the feed processing protocol.
Accordingly, polyacrylamides, GRAS and Food Grade Polymers, are GRAS and can lawfully be used as processing aids in the flocculation and recovery of nutrients such as protein and carbohydrates from food processing waste. The recovered material may then be used in the preparation of feed ingredients for food animals in accordance with the levels of use stated above.
Exemption from Finished Animal Feed Labeling
One might ask whether GRAS and Food Grade Polymers, polyacrylamides, must be declared as ingredients on the labels of finished animal feed products. Section 403(i)(2) of the Act and its implementing regulations, require that the label of a food product, including animal feed product, declare the name of each ingredient in the food, unless there is an exemption for the ingredient. One such regulatory exemption is for “incidental additives” in animal feed. 21 C.F.R. § 501.100(a)(3). A substance comes under the “incidental additives” exemption, among other ways, if it (1) is added to food for its technical or functional effect during processing, (2) is present in the finished food at insignificant levels, and (3) has no technical or functional effect on the finished food. 21 C.F.R. § 501.100(a)(3)(ii)(c)(1997). GRAS and Food Grade Polymers, polyacrylamides meet all three of those criteria and, therefore, because they come under the “incidental additives” exemption, GRAS and Food Grade Polymers do not need to be declared on the label of the finished animal feed. Please see the position paper of the expert panel on the next page.
Opinion Of The Expert Panel
Polyacrylamides exist in three forms, anionic, cationic, and nonionic. The safety of polyacrylamides has been considered previously by U.S. Food and Drug Administration (“FDA”), the U.S. Environmental Protection Agency, and the National Sanitation Foundation (“NSF”). GRAS and Food Grade Polymers, polyacrylamides are widely used as synthetic organic polyelectrolytes in the treatment of drinking water, and are certified by the NSF under the Safe Drinking Water Act. GRAS and Food Grade Polymers, polyacrylamides are also approved by the FDA as direct, secondary direct, and indirect food additives and as thickeners in animal feeds. (21 C.F.R. §§ 172.255, 173.5, 173.310, 176.180, 176.110, and 573.120.) Anionic polyacrylamide is a copolymer of acrylamide and acrylic acid or an acrylate salt (e.g. ammonium or sodium acrylate). Nonionic polyacrylamide is an acrylamide homopolymer. Cationic polyacrylamide is a copolymer of acrylamide and a quaternary ammonium salt.
Polyacrylamides are manufactured by the reaction of the appropriate monomer(s) in the presence of initiators. Each process results in the extremely stable polymer with a high molecular weight (100,000-20,000,000). Residual monomer content for all forms is less than 500 ppm (0.05%) acrylamide, less than 5000 ppm (0.5%) acrylic acid and less than 5000 ppm (0.5%) quaternary ammonium salts. The small quantity of acrylamide monomer present in the polymer distributes in the bulk water of the food waste and is removed from the dewatered solid waste product.
The polyacrylamides will be used as processing aids for ingredients in feed for food-producing animals, including chickens, turkeys, swine, lambs, and beef and dairy cattle. Actual use levels of the feed will depend on the species of animal, but should be no more than 29% of the diet (dairy cattle), because the recovered GRAS and Food Grade Polymer material will represent only a fraction of the finished animal feed.
The Expert Panel considered levels of consumption of meat, milk, and eggs from animals fed the feed containing the polyacrylamide-recovered feed ingredients. Using both the FDA Center for Veterinary Medicine guidelines and the U.S. Department of Agriculture data on human consumption (1994-1996 dataset), the Expert Panel concludes that such consumption of GRAS and Food Grade Polymers poses no risk to humans.
Since the GRAS and Food Grade Polymers are extremely stable, they are not expected to undergo any significant decomposition in the stomachs of the animals which consume them. Polyacrylamides are not expected to be absorbed from the animal’s intestinal tract because of their high molecular weight, and, therefore, will be excreted unchanged. Thus, the Expert Panel concludes that the polymers would not exhibit and toxic effects on the host animal.
The Expert Panel reviewed toxicology studies on anionic, cationic, and non-ionic polyacrylamides which comprise GRAS and Food Grade Polymers as well as the relevant monomers. Published subchronic and chronic studies were reviewed and the no-observed-adverse-effect levels (“NOAEL”) were determined.
The Expert Panel concluded that the polymeric substances, that is the GRAS and Food Grade Polymers, when used in waste processing at levels of 10 g/kg waste solids, represent no risk to consumers.
Based on laboratory animal data and the fact that the GRAS and Food Grade Polymers are not absorbed, there is no reasonable exception that polyacrylamides would be carcinogenic to animals consuming the treated feed or to humans consuming meat, milk, and eggs from such animals. Under FDA regulations governing carcinogenic compounds used in food-producing animals, an animal feed ingredient may be approved even if it contains a carcinogenic contaminant (monomer) as long as the upper bound level of increased cancer risk is less than 1×10-6.
For acrylamide monomer, the Expert Panel reviewed subchronic, neurotoxicity, multi-generation reproductive, genotoxicity, and oncogenicity studies. Based on these published studies, the NOAEL for acrylamide was determined to be 0.2 mg/kg/day. After review of the available data, the ED10 was determined to be 0.19 mg/kg/day and 0.06 mg/kg/day for male and females respectively. Using conservative assumptions, maximum exposure for humans to acrylamide monomer from ingesting meat, milk, and eggs from animals fed processed waste containing these polymers, was estimated to be 3 x 10-9 mg/kg/day. The upper bound added cancer risk from such ingestion was calculated to be 1 x 10-10.
The Expert Panel reviewed published subchronic, chronic, and reproduction studies in rodents on acrylic acid. The NOAEL for acrylic acid was determined to be 83 mg/kg/day. Maximum intake of acrylic acid was determined to be 2.1 x 10-3 mg/kg/day. This results in a safety factor of over 100,000. The Expert Panel concludes that there is no risk to consumers from using anionic polyacrylamides as processing aids in recovered food manufacturing waste used for animal feed.
Based on an estimated exposure of cationic quaternary ammonium monomers to humans, the Expert Panel concludes that the use of cationic polyacrylamides, included in the category of GRAS and Food Grade Polymers, as processing aids in recovered food manufacturing waste used for animal feed, represents no risk to consumers.
Based on the available data to the Expert Panel concludes that:
“anionic, cationic, and nonionic polyacrylamides may reasonably be expected to be safe when used as flocculation aids in the preparation of ingredients to be incorporated into finished animal feed.”