I've been following this for awhile from another forum. Ethoxyquin has been banned for use in human foods. It's used as a preservative and PESTICIDE (that right there should explain it). Quote: Ethoxyquin is a chemical preservative â€“ and possible carcinogenic â€“ regulated by the FDA (U.S. Food and Drug Administration) as a pesticide. While ethoxyquin cannot be used in human foods, it continues to be used in many pet food brands. Ethoxyquin has been found to promote kidney carcinogenesis and significantly increase the incidence of stomach tumors and enhanced bladder carcinogesis, according to several studies, including a recent one by The Department of Pathology, Nagoya City University Medical School, Japan. Quote: 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline. Antioxidant; also a post-harvest dip to prevent scald on apples and pears. Originally developed by Monsanto as a stabilizer for rubber, Ethoxyquin has also been used as a pesticide for fruit and a color preservative for spices, and later for animal feed. The original FDA permit for use as stabilizer in animal feed limited use to two years and did not include pet food, but it falls under the same legal category. It has never been proven to be safe for the lifespan of a companion animal.It has been linked to thyroid, kidney, reproductive and immune related illnesses as well as cancer, but so far no conclusive, reliable research results either for the safety of this product or against it have not been obtained. Monsanto conducted research years ago, but results were so inconclusive due to unprofessional conduct and documentation that the FDA demanded another study. There are currently several studies underway to determine whether Ethoxyquin is safe or not, and until those studies are completed, pet food suppliers may continue to use Ethoxyquin. This is how things stand after about 6 years, and no new details have emerged so far. be heavily preserved with an antioxidant, the recommendation being ethoxyquin. Natural Balance uses E. on any fish meal. Also of interest, suppliers are NOT required to use ethoxyquin - regulations state that the fish meal must be preserved with an antioxidant, but doesn't specify which, although they recommend E. Quote: he websites mentions the Code of Federal Regulations, and if you read the actual code carefully, it simply implies that fishmeal/fish scrap on a shipping vessel entering US waters/ports needs to be heavily preserved with an antioxidant, the recommendation being ethoxyquin. List of Ethoxyquin free foods: ANY Natura product (Innova, Evo, California Naturals) Blue Buffalo By Nature Flint River Ranch Fromm Merrick Petcurean Timberwolf Wellness Orijen Acana Nature's Variety Life's Abundance Halo Horizon Pinnacle Canine Caviar Eagle Pack Avoid Solid Gold for the time being - they claim they do not use, nor have suppliers that use, ethoxyquin - but they are manufactured by Diamond and Diamond stated that ALL their products contain E. Including TOTW, Canidae and Chicken Soup. It is my belief then, that SG also contains it.