GMO Threats by jennyyingdi

VIEWS: 11 PAGES: 47

									GENETICALLY MODIFIED 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
1) Sources of GM food, plants under
  scrutiny
2) Regulation and principles of the
  health risk analysis of GM food
3) Contraversy on the results of GM
  food health risk analysis
4) Conclusions
SOURCES of GM FOOD:
1) MICROORGANISMS
   (e.g. modified lactobacilli, modified yeast,
   enzymes from the modified microorganisms –
   invertase, renin, etc.)
2) ANIMALS
   (super-salmon, vaccine proteins in milk, prion
   protein-less cows)
3) 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
       Frankenstein Food
       Plant Biotechnology
GM plants and derived food and feed that are
currently on the market, have been modified
through insertion of single or 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 GM plant coverage
                                                         1996 - 2010
                       160
                       140
    Million hectares



                       120
                       100
                        80
                        60
                        40
                        20
                         0
                             1996
                                    1997
                                           1998
                                                  1999
                                                         2000
                                                                2001
                                                                       2002
                                                                              2003
                                                                                     2004
                                                                                            2005
                                                                                                   2006
                                                                                                          2007
                                                                                                                 2008
                                                                                                                        2009
                                                                                                                               2010
                                                                       Year


Global Review of Commercialized Transgenic Crops. Clive James, Jan. 2010, ISAAA
The main GM plant growers, 2010

       2% 2% 2%   1%
  2%
6%                       USA
                         Argentina
                         Brasil
6%
                         India
                  46%    Canada
                         PR China
17%
                         Paraguay
                         Pakistan
                         South Africa
        16%              Uruguay
The main GM plant cultivars, 2010
Cultivars      M ha         Adoption Rate
Soybean        73,3             81%
Maize          46,8             29%
Cotton         21,0             64%
Rapeseed        7,0             23%

           Cultivars           M ha
      Herbicyde tolerance      89,3
       Insect resistance       26,3
         Stacked traits        32,3
 GMO accepted in EU for food/feed use,
                2010
  Plant         Events    HerbTol/InsRes/Both/Comp. Scope
  Cotton        6                   2/2/2/0         Food,feed
  Maize         26                  3/9/14          Food,feed/cultivation
                                                    (2)
  Potato        1                   0/0/0/1         Food,feed/cultivation
  Rapeseed      3                   3/0/0/1         Food,feed
  Soybean       3                   3/0/0/0         Food,feed
  Sugar beat    1                   1/0/0/0         Food,feed

Ca. 90 applications are being reviewed
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


Gene                     Form of the         Mr of the protein   Toxicity
                         crystal
cry I; A(a), A(b),       Double pyramid      130 -138 kDa        Lepidoptera
A(c), B, C, D, E, F, G
cry II; A, B, C          Cube or other       71, 71, 69 kDa      Lepidoptera and
                                                                 Diptera
cry III; A, B, B(b)      Flat or irregular   73, 74, 74 kDa      Coleoptera
cry IV; A, B, C, D       Double pyramid      134, 128, 78, 72    Diptera
                         or round            kDa
cry V - cry X            Variable            129, 73, 35, 38     Various groups

                              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
           RISK ANALYSIS
            Risk Analysis
                                         Risk
            Risk
                                      Management
         Assessment
                            Risk
Hazard                  -Likelihood        Risk
                        -Magnitude      Mitigation




          Uncertainty
                                       Cost-Benefit
                                        Analysis




          Risk Communication
    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
Food Safety Authority
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
The safety assessment of GM foods generally
investigates:
(a) direct health effects (toxicity),
(b) tendencies to provoke allergic reaction (allergenicity);
(c) specific components thought to have nutritional or
    toxic properties;
(d) the stability of the inserted gene;
(e) nutritional effects associated with genetic
    modification;
(f) any unintended effects which could result from the
    gene insertion.
`
 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
        Substantial Equivalence
           in EU-Legislation

• 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
• 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
 expressing Galanthus nivalis lectin on rat small intestine
 Stanley W B Ewen, Arpad Pusztai
                                THE LANCET • Vol 354 • October 16, 1999
Diets containing genetically modified (GM) potatoes expressing the lectin
Galanthus nivalis agglutinin (GNA) had variable effects on different parts
of the rat gastrointestinal tract. Some effects, such as the proliferation of
the gastric mucosa, were mainly due to the expression of the GNA
transgene. However, other parts of the construct or the genetic
transformation (or both) could also have contributed to the 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, the author of controversial studies reporting
  soybeans genetically modified for resistance to glyphosate may be
  dangerous to newborns

An unprecedented study claiming that transgenic soybeans
compromise the fertility of rats and the survival and growth
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 Environmental Contamination and Toxicology
Suggesting improvements in feeding tests
Suggesting improvements in feeding tests
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 food
ingredients, 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
of exposure and risk to consumers from nanotechnology-
derived food/food packaging are largely unknown.
                         Food Additives and Contaminants, March 2008;

								
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