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G ENETICALLY M ODIFIED FOOD : REAL OR IMAGINARY RISK?. Prof. Indrikis Muiznieks. UNIVERSITY of LATVIA. The Europeans and GM food : evaluation of four technologies. Can GM food solve shortages ?. OUTLINE. Sources of GM food, plants under scrutiny
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GENETICALLY MODIFIED FOOD: REAL OR IMAGINARY RISK? Prof. Indrikis Muiznieks UNIVERSITY of LATVIA
OUTLINE • Sources of GM food, plants under scrutiny • Regulation and principles of the health risk analysis of GM food • Contraversy on the results of GM food health risk analysis • Conclusions
SOURCES of GM FOOD: • MICROORGANISMS(e.g. modified lactobacilli, modified yeast, enzymes from the modified microorganisms – invertase, renin, etc.) • ANIMALS(super-salmon, vaccine proteins in milk, prion protein-less cows) • PLANTS(nearly all cultivated species modified, few used in large-scale agricultural production)
Genetically Modified Organisms (GMOs) = Transgenics Cultivars developed through genetic engineering • Also known as: • Genetically Engineered Organisms • Genetically Enhanced Organisms • Biotech Crop • FrankensteinFood
Plant Biotechnology GM plants and derived food and feed that are currently on the market, have been modified through insertion of singleor a few genes which express traits, such as providing herbicide tolerance and/or insect resistance. Apart from the intended alterations in their composition, these plants show no evidence for alterations in phenotype and basal composition.
Traditional Plant Breeding • Combines all genes of the parent plants, so both desirable and undesirable traits may be expressed in the plant offspring. • Only plants from the same species, or closely related species can be interbred, which further narrows the sources of potential desirable traits.
Plant Biotechnology • Allows for the transfer of a greater variety of genetic information in a more precise manner. • Using plant biotechnology, a single gene may be added to the strand. • These genes are very specific and allow the plant to precisely express the desired trait.
Global Review of Commercialized Transgenic Crops. Clive James, Jan. 2010, ISAAA
GENETIC MODIFICATION OF PLANTS Genes of interest: examples
GENETIC MODIFICATION OF PLANTS Genes of interest: examples Roundup resistance - modified enzyme 3-enolpyruvilshykimate-5-phpspahate synthetase from soil bacterium
GENETIC MODIFICATION OF PLANTS Genes of interest: examples Bacillus thuringiensis toxin crystal
GENETIC MODIFICATION OF PLANTS Genes of interest: examples Types of Bt toxins
GENETIC MODIFICATION OF PLANTS Gene silencing for novel features b-D-glucuronidase inhibition by antisense mRNS synthesis: Flavr Savr tomato since May, 1994
Potential Risks from GMO used in food or feed • Health risks • Environment risks • Socio-economic risks • Ethical conflicts
Precautionary Principle Described in the Rio Declaration (1992): Nations shall use the precautionary approach to protect the environment. Where there are threats of serious or irreversible damage, scientific uncertainty shall not be used to postpone cost-effective measures to prevent environmental degradation.
Definition of the Precautionary Principle (Cynical American Version) The Precautionary Principle is a nebulous doctrine developed by Europeans as a means to erect a trade barrier against any item that can be produced more efficiently in the United States.
Implications of Problems in European Agriculture • Recent agriculture industry problems in EU countries include: • BSE (Mad Cow Disease) • Hoof and mouth disease • Dioxins in chicken feed • These problems have led to public distrust and to support for the Precautionary Principle. • The Precautionary Principle justifies exclusion of usual US food products, even though the US has had none of these agricultural problems
Codex Alimentarius Commission. Alinorm 03/34: Joint FAO/WHO Food Standard Programme, Codex Alimentarius Commission, Twenty-Fifth Session, Rome, 30 June–5 July, 2003. Appendix III, Guideline for the conduct of food safety assessment of foods derived from recombinant-DNA plants Directive on the Deliberate Release into the Environment of Genetically Modified Organisms (2001/18) Regulation on Genetically Modified Food and Feed (1829/2003) In effect since 19 April 2004 Regulation No 178/2002 laying down the general principles and requirements of food law, establishing the European FoodSafetyAuthority
EFSA - advancing risk assessment in the EU Systems established to ensure improved management/planning of risk assessment (workplan, timelines) transparency risk communication stakeholder engagement interaction of risk assessment/risk management interaction with national authorities
EFSA risk assessment structure • Scientific Committee + 8 Scientific Panels • 156 experts • Additional external experts (working groups) • External agencies • EFSA scientific/management/administrative staff • EFSA Risk Communication function
EFSA-Panel GMO Elements to be considered in the safety assessment process • Molecular characteristics of the GMO taking into account the characteristics of the donor and recipient organisms • Potential environmental impact following a deliberate release • Compositional, nutritional, safety and agronomic characteristics • Potential toxicity and allergenicity of gene products and metabolites • Nutritional assessment of the GM food and feed
Thesafetyassessmentof GM foodsgenerallyinvestigates: • directhealtheffects (toxicity), • tendencies to provokeallergicreaction (allergenicity); • specificcomponentsthought to havenutritionalortoxicproperties; • thestabilityoftheinsertedgene; • nutritionaleffectsassociatedwithgeneticmodification; • anyunintendedeffectswhichcouldresultfromthegeneinsertion. • `
Processing of the applications for food and feed that was made from or contains GM plants 1) Application submitted to EFSA 2) Scientific evaluation from expert committee 3) Recommendation made by EFSA 4) Draft for decision from the European Commission Vote in the "Standing Committee for the Food Chain and Food Safety" (Member States) The European Commission's draft may be accepted or rejected with a qualified majority. If no qualified majority can be reached, the European Commission submits its draft to the Council of Ministers. 5) Vote in the Council of Ministers. Approval or rejection by qualified majority - without qualified majority the Commission's draft takes effect. Regulation 1829/2003
Substantial Equivalence Expert Consultations convened by FAO/WHO and OECD have recommended that substantial equivalence be an important component in the safety assessment of foods derived from GMP . Not to establishing absolute safety but to consider whether the GMF is as safe as its traditional counterpart
not explicitly detailed in EU legislation Simple procedure (Art 5)in Novel Food Regulation “Substantial Equivalence” on the basis of the scientific evidence available and generally recognized or on the basis of an opinion delivered by one of the competent bodies Substantial Equivalence in EU-Legislation
Substantial Equivalence in EU-Legislation • SE-Data widespread – no special chapter • composition data of raw products and/or processed products and/or information on processing (and exposition and/or consumption) are scattered throughout dossiers • Composition analyses: GLP not evident • Analyses of kernels – extended to processed products • Maize dossiers: only descriptions of processing procedures • Rape dossiers: Data of processed products (limited scale and set of parameters) • Barely Data on Consumption
Substantial Equivalence in EU-Legislation • Solid statistical evaluation questionable • No continuous statistic evaluation • Missing information on methods/software/CI --> Cannot be concluded, that in each case the statistical evaluation is actually state of the art • Significant/remarkable compositional differences in all dossiers • Differences dismissed without adequate explanation or by arbitrarily citing literature ranges or „normal“ ranges • No rerun of analyses taking into account a broader spectrum of compounds • To get a better overview on compositional equivalence and • To better address the hazard of secondary/unintended effects
Weaknesses SE • Compositional analyses as screening method for unintended effects of the genetic modification has its limitations • in particular regarding unknown anti-nutrients and natural toxins • “finer screening” - DNA analysis, messenger-RNA fingerprinting, protein fingerprinting, secondary metabolite profiling and in vitro toxicity testing
Nutritional Evaluation • Low-glutelin-Rice - unintended increase in levels of prolamins (not relevant for sake-brewing but in case of nutrition) • would not have been detected by standard composition analyses (total protein; AA-profiles) • „Golden Rice“ - unexpected accumulation of xanthophylls • would not have been apparent from standard analyses
Allergenicity. As a matter of principle, the transfer of genes from commonly allergenic foods is discouraged unless it can be demonstrated that the protein product of the transferred gene is not allergenic. While traditionally developed foods are not generally tested for allergenicity, protocols for tests for GM foods have been evaluated by the Food and Agriculture Organization of the United Nations (FAO) and WHO. No allergic effects have been found relative to GM foods currently on the market.
Contraversies in GM food health risk assessment In 1998 Árpád Puzstai said in an interview on a World in Action programme that his group had observed damage to the intestines and immune systems of rats fed the genetically modified potatoes. He also said "If I had the choice I would certainly not eat it", and that "I find it's very unfair to use our fellow citizens as guinea pigs". Wikipedia
Contraversies in GM food health risk assessment Effect of diets containing genetically modified potatoes expressingGalanthus nivalis lectin on rat small intestine Stanley W B Ewen, Arpad Pusztai THE LANCET • Vol 354 • October 16, 1999 Diets containing genetically modified (GM) potatoesexpressing the lectin Galanthus nivalis agglutinin (GNA) hadvariable effects on different parts of the rat gastrointestinaltract. Some effects, such as the proliferation of the gastricmucosa, were mainly due to the expression of the GNAtransgene. However, other parts of the construct or thegenetic transformation (or both) could also have contributed tothe overall biological effects of the GNA-GM potatoes,particularly on the small intestine and caecum.
Contraversies in GM food health risk assessment GM soybeans and health safety—a controversy reexamined NATURE BIOTECHNOLOGY VOLUME 25 NUMBER 9 SEPTEMBER 2007 Irina Ermakova, theauthor of controversialstudies reportingsoybeans geneticallymodified for resistanceto glyphosate maybe dangerous tonewborns An unprecedented study claiming that transgenic soybeans compromise the fertility of rats and the survival andgrowth of their offspring has garnered widespread media and political attention but remains unpublished in the peer-reviewed literature.
Gilles-Eric Séralini. et al. (2007) New Analysis of a Rat Feeding Study with a Genetically Modified Maize Reveals Signs of Hepatorenal Toxicity Archives of EnvironmentalContamination and Toxicology
Recommendations Standardise – and rationalise – the principles involved in the evaluation and approval of new crop varieties (whether produced by so-called conventional, marker assisted breeding, or GE technologies) universally so that they are scientific, risk-based, predictable and transparent. It is critical that the scope of what is subject to case-by-case review is as important as the actual review itself; it must also be scientific and risk-based. PAS Study Week, Vatican City, 15-19 May 2009
New challenges for health risk assessment Nanotechnology applications are expected to bring new tastes, textures and sensations, less use of fat, enhanced absorption of nutrients, improved packaging, traceability and security of food products. Nanotech-derived food products are set to grow worldwide anda variety of foodingredients, additives, carriers for nutrients/supplements and food contact materials is already available. The current level of applications in the European food sector is at an elementary stage; however, more and more products will be available in the EU over the coming years. The toxicological nature of hazard, likelihood ofexposure and risk to consumers from nanotechnology-derived food/food packaging are largely unknown. Food Additives and Contaminants, March 2008;