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GMO* and Food Safety. Dr. Ted Labuza Department of Food Science and Nutrition Univ. Of Minnesota St Paul 55108 tplabuza@umn.edu http://fscn.che.umn.edu/Ted_Labuza/tpl.html. * Frankenfoods ???. Safety issues over “GMO”. Classic toxicity testing Substantial equivalence
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GMO* and Food Safety Dr. Ted Labuza Department of Food Science and Nutrition Univ. Of Minnesota St Paul 55108 tplabuza@umn.eduhttp://fscn.che.umn.edu/Ted_Labuza/tpl.html * Frankenfoods ???
Safety issues over “GMO” • Classic toxicity testing • Substantial equivalence • Pre-cautionary principal vs risk benefit • Identity preservation • labeling
Poisonous or Deleterious Substances • general toxicity • carcinogens • mutagens • teratogens
Food Drug and Cosmetic Act • 402(a)(1) - a food is adulterated if it contains any poisonous or deleterious substance which may render the food injurious to health
Food Drug and Cosmetic Act • 402(a)(1) - a food is adulterated if it contains any poisonous or deleterious substance which may render the food injurious to health • Microbial example : pathogens such as E. coli O157:H7
Food Drug and Cosmetic Act • 402(a)(1) - a food is adulterated if it contains any poisonous or deleterious substance which may render the food injurious to health • Chemical examples : lead, PCBs, dioxin, mercury, • radio-nucleotides, pesticides
Food Drug and Cosmetic Act • 402(a)(1) - a food is adulterated if it contains any poisonous or deleterious substance which may render the food injurious to health • Relates to unapproved substances added by man intentionally or non-intentionally
Food Drug and Cosmetic Act • 402(a)(1) - however if not added*, the food is not adulterated if the quantity would not ordinarily render injurious to health example - solanine in potatoes • New level of consumption • More susceptible population * meaning naturally present So could apply to a GMO
Questions What level of toxicant is tolerable, if any? What level of toxicant is detectable ?
Food Additives Amendment 1958 • 402(a)(2) A food is adulterated if it contains any added poisonous or deleterious substance except one that is either: • Food Additive (Sec 409) • Generally Recognized As Safe 201(s) • Color Additive (Sec 706) • Pesticide (Sec 408) - clarified as not an additive • Note that “added” means intentional addition so would apply to GMO unless exempt as additive or GRAS
Additive Definition 201(s) • “ any substance, the intended use of which may reasonably be expected to result directly or indirectly in its becoming a component or otherwise affecting the characteristics of any food.”
Additive testing history • Based on traditional toxicity testing • FDA Red Book - 1982 1st edition • LD50 acute toxicity • Sub-acute toxicity • Life time chronic feeding trials • Safety based on 100th of the level of NOAEL • Also applied to GRAS substances
Decision process • Rodricks Food Tech. March 1996 pg 114 • EDI (estimated daily intake) < NRI (negligible risk intake) • Assessment • Natural components • Unintentional contaminants • Intentionally added constituents- ADI • Added 10x10 fold factor to estimate NRI • GRAS related
Test design constraints for GMO food • Generally max level of % 5 dry solids in test animal diet per day • Equivalent to dose of ~2500 mg/Kg /day in 50 g diet for 1 Kg animal • If no effect and use 100x factor then ADI = 25mg/Kg/day so in 70 Kg human ~1.8 g/day so if GMO with 95% moisture ~ 1 ounce serving
Sec 409 (c)(3)Delaney Clause No regulation shall issue if a fair evaluation before the Secretary (FDA) (a) fails to establish that the proposed use shall be safe provided that no additive shall be deemed safe it it is found to induce cancer when ingested by man or animal or if it is found after tests which are appropriate for their evaluation of the safety of food additives to induce cancer in man or animals
Delaney Clauseexclusions • GRAS substances prior to 1958 • Pesticides - FQP Act • Dietary supplements (note under NLEA FDA needs to prove unsafe)
GRAS • Sec 201 (s) • Except food additive does not mean such substance that is generally recognized as safe (GRAS) among experts qualified by scientific training and experience to evaluate the safety, through adequately shown scientific procedures or in the case of a substance used in food prior to Jan.1 1958 through either scientific procedures or common use in food to be safe under the conditions of its intended use.
Natural Carcinogens • Mushroom Example Agaratine- DNA breaker at 1.2 mg/70 Kg person • present in mushrooms • Calculated safe dose < 4 g mushroom per day or 1 meal every 100 days • Foods are GRAS so exempt
Fmali Herb Inc. v Heckler • 715 F 2d 1385, 1982 (DC ND CA 9/15/83) • Block list on renshan-fenwang-jiang from Korea • Basis not GRAS since not consumed in US prior to 1958 • Fmali sues to lift ban • Court agrees that GRAS means anywhere in world not just US thus if used can bring in • 53 FR 16544 5/10/88 - substantial use as an ingredient for food by a significant number of consumers
GRAS Review 21 CFR 170(f) • (1) modified substances of natural biologic origin consumed prior to 1958 but modified afterwards • (2) significant alteration of prior 1958 natural substances by breeding and in which the nutritive value or toxicity changes
Classical Breeding History • UM, NDSU and USDA potato research lab development of improved chipping variety of potato (Lenape) (Zitnak and Johnston Am Potato Jr 47:256-60) • Submitted to FDA for approval but found increased solanine level so withdrew from introduction
Classical Breeding History • Discussion at Hort. Science meeting • published in 1975 Spiher A.T. The Growing of GRAS Hort Sci. 10:241-42 1975 • Approval based on nutrient level and toxicological levels
The Issues • What category of food ingredients do GMO based varieties it into ? • What safety criteria are needed in testing, ie what are the protocols ? • What does substantial equivalence mean? • What does “precautionary principal mean?
1987 National Academy of Sciences • Introduction of recombinant DNA-engineered organisms into the environment: Key issues • No evidence of unique hazards • Risks similar to introduction of unmodified organisms or those modified by other methods
The FDA Policy • 57 FR 22983-23005 May 29, 1992 The safety of foods derived from new plant varieties • (Note never finalized -guidance to industry) • Basic premise is that plant breeding produces safe foods vs chemicals which may be toxic • Genetic transferred material may be subject to food additive or GRAS process • (DNA itself not a concern IFBC 1990 • Miragila et al 1990 safety assessment of genetically modified food products Microchem J 59;154-9)
The FDA Policy • 57 FR 22983-23005 May 29, 1992 The safety of foods derived from new plant varieties • Toxicant level suggested ^ by 10% and Nutrient level suggested decrease of 10% • Is there a potential allergen ? • Kessler et. al. The safety of foods developed by biotechnology Science 256:1747 1992 • Current working policy - 45 products have been evaluated • 12 corn, 7 canola, 6 tomato, 5 cotton, 4 potato • see IFT Expert Report on Biotechnology http://courses.che.umn.edu/01fscn11021s/general_food_safety/gmo/gmo.html
Basis of policy • 402 (a)(1) of FFDC • see Ronk et al Hort Sci 25;1482-84 1990 • Animal feeding studies problematic • Animal tests not sensitive as cannot supplement at high enough level • Need multidisciplinary assessment process based on • genomic traits • Agronomic and quality analysis • Allergenicity potential • Analysis of toxicants and nutrients Maryanski, J. FDA’s policy for Foods Developed from Biotechnology in Genetically Modified Foods: Safety Issues Engle et al Eds. ACS Symposium Series # 605 1995 pgs 12-22
Basis of policy • 402 (a)(2) of FFDC • will need approval as food additive if introduced protein is different than normal otherwise GRAS • Special attention should be given to potential allergens - see April 1994 FDA conference on “Scientific issues related to potential allergenicity in Transgenic Food Crops FDA Docket # 94N-0053 also in 59 FR 15415 April 1, 1994
OSTP 1994 • Coordinated Framework for US Biotechnology Policy • 51 FR 23302 June 26, 1986 • Exercise of Federal oversight • 57 FR 6753 Feb 24 1992 • Use risk based scientific approach rather than process used (ie don’t focus on biotech process rather use the standard safety evaluation process)
The Genetic Raw Potato • Ewan and Pusztai Lancet 354:1353-4 Oct. 16, 1999 • Effect of diets containing genetically modified potatoes expressing Galanthus nivalis lectin on the rat small intestine (insect resistance) • crypt hyperpalsia suggested expression of other genes
Early Genetic Engineering of GRAS Ingredients in Foods • The first round: chymosin • recombinant technology • Inserted gene for calf rennet into E. coli • >80% of world cheese making
Early Genetic Engineering of GRAS Ingredients in Foods • The first round: chymosin • Deemed to be GRAS • 57 FR 10932-6 23/3/90 E coli • 57 FR 6476-9:1992 yeast • 58 FR 27197-203: 1993 mold • See Flamm E.L. Bio/Technology 9:340-351 ; 1991 • Same protein structure • Most impurities removed • Organism destroyed in processing • Anti-biotic resistant marker destroyed
Early Genetic Engineering of GRAS Ingredients in Foods • High-fructose corn syrup • recombinant enzymes • Bound on reactor bead surface so does not go into food - processing aid • Converts glucose to fructose
The first controversy - Monsanto Milk - Recombinant BST or rBGH Neither GRAS nor Food Additive rather It is an approved New Animal Drug
Flavor-Savr Tomato • Calgene asks for food additive status for enzyme FDA Docket # 90A-0416, 91A-0330 • FDA findings • enzyme introduced well documented @ <0.16 ppm and digested 59 FR 26700-711 May 23, 1994 • Marker gene easily digested -FDA suggests that should use kanamycin marker in all GMO • Nutrient level the same • No change in toxic substances- tomatine alkaloid • No need for special labeling • Redenbaugh et al Regulatory Issues for the commercialization of tomatoes with an anti-sense polygalacturonase gene In-Vitro Cell Devel Biol 29P:17-26 1993 • 59 FR 26700-711 may 23, 1994
FDA Approvals • 1994 - squash resistant to diseases • 1995 potato insect resistant • 1996 Soybean - herbicide resistance • 1997 corn - corn borer resistance
WHO-FAO • 1993 - marker genes not a safety issue (< 1/250,000 of DNA consumed) Report 93.6 • 2000 - reconfirms prior statement “safety aspects of genetically modified food of plant origin”
Nature Biotechnology Volume 18 Number 11 p 1119; 2000 First, food safety and labeling-the editorial says let's state once and for all that safety and labeling standards for foods, food ingredients, and feeds should be applied regardless of the techniques used in their production and manufacture. There is widespread Expert consensus about this (in fact, genetic engineering may be safer/more precise than conventional breeding), so why is it even discussed anymore?Foods should continue to be assessed on the basis of substantial equivalence, with labeling required only for (GM) foods that differ significantly in composition or nutritional value from their conventional counterparts.
Substantial Equivalence Principles • Term is not in any FDA document • Reduction by 10% in key nutrients • Increase by 10% in natural non-added background toxicants • New proteins well characterized and appear in other foods • Source of gene well characterized • Need for feeding trials questionable • Concern for allergenicity - from typical allergenic food or properties flag as allergen
The Legal Dilemma • All plants approved have been patented • Patents are • New • Novel • Non-obvious • ie Substantially different
OECD 2000 • UN Organization for Economic Cooperation • Safety of new and novel foods • Safety based on substantial equivalence
EPA • FIFRA • 7 USC 136(a) -136® • Regulates pesticides • FQPA 1996 • Pesticide is not a food additive • Stricter evaluation process especially with respect to children exposure
EPA principles • GMO’s are flagged if they are introduced as a pesticide • Must submit for approval • Under FPA pesticide compounds which include new GMO plant varieties are excluded from Delaney Clause ie they are not considered as additives • Use of precautionary principle
EPA Precautionary Principles • Mission to protect human health and safeguard environment within “adequate margin of safety” • Question of available data vs need to extrapolate • Nature of the risk ie if there is a carcinogen risk in introduction use of precautionary assumptions ie projection of risk on the safe side
USD - APHIS • Fed Plant Pest Act 7 USC 150 - regulates introduction of “plant pests” that cause injury, death or damage to any plant 7 CFR 340
GMO: the new potential threat • Crossing transgenic species • Brazil nut with soybeans for methionine • Fish antifreeze protein in ice cream