The Problem with Ethoxyquin


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    August 17, 1992

    Dr. David A. Dzanis
    Veterinary Nutritionist
    Div. of Animal Feeds; FDA HFV-222
    7500 Standish Place
    RockvilIe, MD 20855

    Dear Dr. Dzanis;

    I am writing to you about the dangers of Ethoxyquin used as a preservative in many pet foods and human foods. Since you are responsible for pet food issues within the FDA and will be meeting with two concerned dog breeders next month concerning the safety of this chemical, I wish to present my own experiences and knowledge of Ethoxyquin’s toxic affects, first hand.

    First of all, let me introduce myself; l am a veterinarian, a graduate from the University of California Veterinary Medical School, Davis, California, class of 1960.1 had a small animal practice in San Ramon, California (a rapidly growing area east of San Francisco) for 31 years and am now retired.

    During those many years I saw a change emerging in the disease and illness of animals presented to me. In the early 1960s, our concerns were primarily those of infectious agents causing Canine Distemper, Feline Distemper, Hepatitis, leptospirosis, staph and strep infections, etc.

    However during the 197Os and to the present time we are seeing an epidemic of chronic degenerative diseases. True, the widely accepted program of preventative vaccination programs virtually wiped out the viral caused diseases and antibiotics helped stem the bacterial infections, but something else is operative here. We are now seeing both in the animal and human populations, a sharing of chronic degenerative diseases such as generalized allergies, arthritis, dermatitis, congestive heart failure, kidney failure, liver pathologies, diabetes, AIDS, tumors and cancer. Also, lifespans of animals have shortened during this period.

    I remember, as a kid growing up in Nevada seeing Basque sheep-herders with working dogs living to be 2l-25 years of age. These dogs were still herding sheep at that age, and the bitches were delivering litters of healthy puppies at 20 years of age! Today, we are lucky to find dogs living to be 10 years old, and many of these suffering from various forms of chronic degenerative disease. Of course in the 1 940s our air, water and food was clean and virtually free of chemicals. My shepherd friend’s dogs worked in clean air, ate fresh lamb stew and vegetables and home-baked bread along with his master. As a dog show veterinarian I have heard many judges say there is a definite difference to the feel of the muscles and skeleton of dogs in Australia than those of America. The Australian dogs’ muscles are firm, bones firm and strong cornpared to the “mushy” feel of the American dogs. Why? Because these animals’ diets are vastly different. The Australian dogs were being fed (until recently-now there is an emergence of commercial pet food) trimmings from the freshly killed beef and sheep carcasses, vegetables and fresh grains, ours on commercial kibble and canned dog food with every chemical residue and preservative and coloring in the book! And forget all the highly touted advertising and P.R. by the pet food industry -I say put garbage in get garbage out!

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      In the good old days, the family pet ate from the same “pot,, so to speak, as the owner/family did, and were healthier for it Not only are chronic degenerative diseases of pets on the increase, but breeders complain of increasing frequency and numbers of reproductive problems: irregular estrus cycles, missed conceptions; stillborns, “fading puppy” syndrome, increased neo-natal deaths and malformed puppies with missing limbs, organs, hydrocephalus, cleft palates, etc.

      Historically, I was first alerted to Ethoxyquin’s (heretofore being referred to as “E”) possible health hazard to dogs, when Midge Harmer, a breeder of German Shepherd show and obedience dogs in Newark, Delaware contacted me on February 12, 1988. She related her heartbreaking experience of losing four of her young champions to liver cancer. Since she had changed nothing in her program of rearing these dogs except switching their diet to feeding ANF (Advanced Nutritional Formula), she looked into the ingredients and found “E” as a preservative. She asked me if I had any experience with this preservative and its effect on animal health. Thus started a four-year quest into finding out all we could on this chemical. I hadn’t any known knowledge about or its related toxic affects to animal health until I started looking into it. I next met a breeder at the Golden Gate Dog Show in San Francisco that same year. She told me of suddenly developing 82% mortality in her puppies (Mm. Pinchers, and Boston Terriers). Out of 27 puppies born she was lucky to save 5. Many others were stillborn and malformed with cleft palates, and hydrocephalus. These problems were atypical. She had not changed any variables (including breeding stock) except for changing the diet to ANF because of the highly favorable advertising put out by the manufacturers.

      I contacted the Dept. of Agriculture for toxicology information on “E.” They sent me a copy from their Farm Chemical Hand-book listing “E” as a pesticide, used in fruit scald control. It is also used as a rubber preservative. I have since learned “E” is FDA approved for use as an antioxidant for carotenes vitamin A and E and the prevention of the development of organic peroxides. It is approved at 150 ppm in paprika and chili powder, and because it is used as a preservative in livestock feed, the following residue allowances in human consumed animal products as follows: 5 ppm in or on the uncooked fat of meat from animals except poultry; 3 ppm in or on the uncooked liver and fat of poultry, 0.5 ppm in or on the uncooked muscle meat of animals, 0.5 ppm in poultry eggs, and zero in milk.

      We have learned “E” is used as a preservative in such widely marketed dog foods as ANF, NutriMax, Hills Prescription Diet WID (sold in vet hospitals!), Nutro, Purina, IAMS, Royal Canine USA; and in livestock feeds by Willowbrook Mills in Petaluma to preserve Crumbles for laying chickens, and dehydrated forage crops of alfalfa, barley, clovers, corn, oats, wheat, fescue and various grasses. The above information brings up the question why the FDA allows such a small amount of “E” residue (5 to .5 ppm) in human consumed foods yet allows such high amounts (150 ppm) to be used in petfood and livestock feeds? In the case of the dog, pound for pound, a dog weighs 115 to 1/lath (NOTE: this figure or word did not come through) the weight of a human (except for giant breeds of dogs) yet is consuming 300 times more “E” than allowed for people. Also many dog food manufacturers are not listing “E” as an ingredient on the packaging. Only under much investigation will they admit it. Isn’t there an FDA regulation about labeling ingredients? Truth in labeling is another issue – ANF, which incidentally is one of the most expensive dog foods, is touted by the manufacturer as an “all natural formula” with no preservatives, yet lists “E” as an antioxidant which they claim to be quite safe.

      Correspondence with various people revealed other dog owners breeders having sad experiences with pets eating “E” preserved dog food:

      1. A breeder of Rottweilers lost a dog with liver cancer after switching to feeding ANF for 6 months.

      2. A German Shepherd breeder lost a stud dog to cancer of the mouth, feeding dog food containing “E.”

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        3. A woman had skin allergies develop in her German Shepherd fed on NutroMax (“E” preserved) and then switched to Solid Gold (no “E”) with the dermatitis allergy disappearing.

        4. Dr. Pia Peters, Ph.D. claims that when she was studying in Ireland for her degree in agriculture (1983-4) she became interested in a news story relating that farmers in Italy suddenly had calves born with eyes on the backs of their heads, no ears, two or three legs only, or legs developing turned backwards, etc. Dr. Peters claims the culprit was “E” in the animal feed fed to the breeding stock.

        5. A breeder first of Poodles, then Collies, had been free of whelping problems; her bitches came into estrus every 6 months “like clockwork,” and all whelped normal healthy litters, then a few years ago she began noticing changes in the dogs’ overall appearance. She was now seeing dry, lustreless coats, flaky skin, and nose pigmentation fading. A friend of hers who raises labradors, Newfoundlands, Collies, and Old English Sheep dogs, had similar problems. Then Elaine’s Blue Merle stud dog (sire of all her dogs) began drooling and bleeding from the mouth. From a biopsy, her veterinarian diagnosed an immune breakdown triggered by a virus or chemical. Her bitches who had not previously come into estrus were now delivering litters of malformed puppies; two were born without legs, tails or any sex organs. (the problems in these two kennels were traced to a change in diet fed the dogs, from one free of “E” preservative to a dog food with “E” preservative.)

        6. Another German Shepherd breeder in Pennsylvania lost a puppy fed Pro Plan (“E” preserved) to a fast growing cancer in both hips.

        Some of the damning information on “E” comes from Monsanto’s own cautionary warnings in using and handling this product. They warn that it may cause allergic skin reactions, irritation to the eyes and skin. They advise that workers must wear eye and respiratory protection. The container of “E” has a very prominent skull and crossbones with POISON written in capital letters. “E” is listed and identified as a hazardous chemical under the criteria of the Osha Hazard Communication Standard (29 CFR 1910, 1220). Monsanto further states the disclaimer regarding the use of “E,” that “Although the information and recommendations set forth herein are presented in good faith. . . Monsanto Company makes no representations as to the completeness or accuracy thereof. Information supplied upon the condition that the persons receiving same will make their own determination as to its suitability for their purposes prior to use. Monsanto will not be responsible for damages of any nature whatsoever resulting from the use of or reliance upon information.” If the company who makes it won’t stand behin4 it, how can the general public accept its safety as a preservative for their pets’ food and directly for themselves and indirectly as residues in human consumptive food products from “E’s” use in livestock feed?)

        I further learned from the Chemical Toxicology of Commercial Products (Ref. Gosselin et al., 1984) that “E” has a toxic rating of 3 (on a scale of 1~, with 6 being super toxic requiring less than 7 drops to produce death), slowly developing depression, con-vulsions, coma and death; skin irritation and liver damage.

        I wrote a letter to my Board of Examiners in Veterinary Medicine, expressing my concern about the safety of feeding dogs foods with “E” as a preservative. I urged them to look into the matter and suggested that with such information wouldn’t it be prudent to recommend to the FDA to ban “E” as a preservative until more definite safety studies be made? The Board responded that I was “overreacting” without scientific proven evidence that the food is the cause of problems cited and that I “refrain from voicing my opinions until there is proven scientific and official evidence that those opinions are true.” The Board was complacent with the FDA approval of “E” based on a five-year safety study done on dogs by Monsanto some 30 plus years ago. That study, I found was grossly incompetent.

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          Let me tell you about what I learned about this so-called scientific” study by Monsanto. The study is fraught with incompetent, slip-shod methods, and erroneous conclusions that by today’s standards of testing would be laughed out of the room. For example, there were never any truly controlled studies on these dogs with the only variable being the feeding or not feeding of “E” and then evaluating the health results. Instead, bitches were kept with males, some dogs were kept indoors, others outdoors, there was no preventative care of vaccination and parasite control so all dogs could start equally – many dogs in the study succumbed to Canine Distemper, Hepatitis and one from Heartworm. Many showed heavy parasite infestations, and fight wounds, etc. E” was fed on a one time a day, 5 days a week basis instead of twice daily 7 days a week which is routinely done in the “real world” by dog owners. Of the 67 puppies who were unfortunate enough to be born during this 5 year study, 32 puppies died. That’s a 50% mortality rate!

          The “scientists” claimed the deaths were due to “under developed and weak puppies”! Isn’t that exactly what we are seeing in litters from breeding stock fed dog food preserved with “E”? To my knowledge nothing was reported in the study of the appearance of coat, pigmentation of the nose, skin health, etc. Changes like these would be an early indicator of liver and immune system pathology. Another discrepancy is the lowered frequency of feedings and relatively short time of the study (5 years vs. 6 or more years of feeding “E” preserved food and seeing cancer developing.) Nothing, to my knowledge, was reported in the study of the nature of the reproductive cycles in the bitches; numbers of missed or irregular estrus, sterility) as we are seeing clinically. Was any blood work done? Liver and thyroid panels?

          I believe not. I believe it is highly unethical for self serving employees to be the scientists in charge of evaluating a product’s safety manufactured by the company who pays their salaries! I would like the FDA to foster safety studies on products by independent testers other than the manufacturer of the product. Perhaps such a plan could be funded by a safety study “fee” levied on the manufacturer who is applying for FDA approval of their product. These monies could then be paid directly by the FDA to the independent testers, thus minimizing possible bias in the report findings.

          While we’re on the subject of product safety studies using live animals I must voice a deeply felt objection to the use of live animals in any research study. It has been proven many times that there are viable alternatives to live animal models, i.e., computer model software, tissue culture and embryo studies. Why not use the tissue cultures of the target organs affected by chemicals? These as you know are the brain, nervous system. endocrine glands (pituitary, adrenal, testes and ovaries, thyroid, thymus, pancreas, etc.) as well as those of the immune system (spleen, liver, lymph nodes, bone marrow, etc.), and are the most acutely sensitive to any toxic substance or radiation. This is where pathology starts immediately. It’s months or years later before the whole organism shows signs of illness. I firmly believe all animals were created equal with man by our Creator, and that the Animal Kingdom has given its silent permission to man to provide him with sustenance, creature comfort, transportation, as beasts of burden and in the case of our pet animals, their unconditional love. Is this how we repay them? Dr. Dzanis, both you and I have a covenant with the Animal Kingdom from the day we graduated from Vet School and took the Hippocratic Oath. We solemnly swore to safeguard the health and well being of all animals and to never do anything to harm them. I have kept my promise. as I am sure you are keeping yours, but it would do well for all mankind to take and uphold that oath in today’s growing moral bankruptcy, people are too willing to turn a blind eye and squeeze every cent out of a transaction at any costs. Perhaps we should rename it the “Hypocritical Oath??

          Gloria Dodd DVM

          My own Note to this:
          When my lovebird Gazer died from Visceral Gout, the vet and I discussed the occurrence of “hotspots” of either chemicals such as ethoxyquin or vitamins/minerals in prepared / formulated diets. So even though the manufacturers say that the small quantities contained in each batch could not possibly cause damage, what if — and this does happen due to badly calibrated / malfunctioning equipment — the chemicals / supplements are concentrated in one batch? This is something to think about.

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