Title: Food Safety: Transgenics and Pesticides
1Food Safety Transgenics and Pesticides
- Michael Hansen, Ph.D.
- Senior Scientist
- Consumers Union, US
- Conselho Regional de Medicina do Estado de São
Paulo - São Paulo, Brazil
- April 26, 2010
2Outline
- A. US FDA Policy on Genetically Engineered
plants - B. Bt crops--potential allergenicity and
immunogenicity concerns - C. Unexpected Effects
- D. Do GE crops reduce pesticide use?
- E. Toxicity of glyphosate
- F. Conclusion
3FDA Policy on Genetically Engineered Plants
- Introduced at press conference at an industry
gathering on May 27, 1992 by then Vice-President
Dan Quayle as a deregulatory initiative - Based on notion that the new techniques e.g.
genetic engineering are extensions at the
molecular level of traditional methods and will
be used to achieve the same goals as traditional
plant breeding (57 FR 22991, May 29, 1992) - No requirement for human safety testing, only
voluntary safety consultations to date, some
80 voluntary safety consultations have been held
4Key phrases in US Food and Drug Administration
safety consultation letters
- Letter for MON 810 (Bt corn), dated Sept. 26,
1996 - Monsanto submitted a summary assessment of corn
containing transformation event MON 810 on June
6, 1996 - Based on the safety and nutritional assessment
you have conducted, it is our understanding that
Monsanto has concluded that corn products derived
from this new variety are not materially
different in composition, safety, and other
relevant parameters from corn currently on the
market, and that the genetically modified corn
does not raise issues that would require
premarket review or approval by FDA.
www.cfsan.fda.gov/acrobat2/bnfL034.pdf - These two sentences found in all 80 safety
consultation letters - FDA does not require premarket safety assessment
and does not state its own opinion about the
safety of the GE crop
5Bt crops
- Engineered with endotoxins produced by the soil
bacterium Bacillus thuringiensis - Endotoxins are called Cry proteins and there are
many of them - Bt crops on market include corn, potato, cotton,
poplars many are in testing phase, including Bt
rice, Bt brinjal, Bt soy - Concern over allergenicity and immunological
impacts of Cry proteins on the gut
6Joint FAO/WHO Expert Consultation on
Allergenicity of Foods Derived from
Biotechnology, January, 2001
- http//www.fao.org/es/ESN/food/risk_biotech_allerg
en_es.stm - Conclusions
- The Consultation emphasized that all foods
derived from biotechnology must be assessed for
allergenic potential
7Joint FAO/WHO Expert Consultation on
Allergenicity of Foods Derived from
Biotechnology, January, 2001
- 7. The Consultation was of the opinion that an
evaluation of proteins for sequence homology with
sufficient sensitivity and specificity to detect
potential cross-reactivity is an important part
of the process for the assessment of the
allergenicity of the expressed protein.
8Joint FAO/WHO Expert Consultation on
Allergenicity of Foods Derived from
Biotechnology, January, 2001
- 6.1. Sequence Homology as Derived from Allergen
Databases - The commonly used protein databases (PIR,
SwissProt and TrEMBL) contain the amino acid
sequence of most allergens for which this
information is known. However, these databases
are currently not fully up-to-date. A
specialized allergen database is under
construction. - Cross-reactivity between the expressed protein
and a known allergen (as can be found in the
protein databases) has to be considered where
there is 1) more than 35 identity in the amino
acid sequence of the expressed protein (i.e.
without the leader sequence, if any), using a
window of 80 amino acids and a suitable gap
penalty (using Clustal-type alignment programs or
equivalent alignment programs) or 2) identity
of 6 contiguous amino acids. - If any of the identity scores equals or exceeds
35, this is considered to indicate significant
homology within the context of this assessment
approach. The use of amino acid sequence
homologies to identify prospective cross-reacting
allergens in genetically-modified foods has been
discussed in more detail elsewhere (Gendel,
1998a, Gendel, 1998b).
9Joint FAO/WHO Expert Consultation on
Allergenicity of Foods Derived from
Biotechnology, January, 2001
- Recommendations
- 1. The Consultation recommends that the FAO/WHO
2001 decision tree be used for determining
allergenicity of foods derived from biotechnology
10Joint FAO/WHO Expert Consultation on
Allergenicity of Foods Derived from
Biotechnology, January, 2001
- Recommendations
- 1. The Consultation recommends that the FAO/WHO
2001 decision tree be used for determining
allergenicity of foods derived from biotechnology
11(No Transcript)
12Kleter, G.A. and A.C.M Peijnenburg. 2002.
Screening of transgenic proteins expressed in
transgenic food crops for the presence of short
amino acid sequences identical to potential,
IgE-binding linear epitopes of allergens. BMC
Structural Biology, 2 8.
- www.biomedcentral.com/1472-6807/2/8
- Compare transgenic protein from GE/GM crop with
known allergen, looking for identical stretches
of at least 6 amino acids - Screen positives further with
- Epitope database
- Antigenicity prediction algorithm
13Kleter, G.A. and A.C.M Peijnenburg. 2002.
Screening of transgenic proteins expressed in
transgenic food crops for the presence of short
amino acid sequences identical to potential,
IgE-binding linear epitopes of allergens. BMC
Structural Biology, 2 8.
14Kleter, G.A. and A.C.M Peijnenburg. 2002.
Screening of transgenic proteins expressed in
transgenic food crops for the presence of short
amino acid sequences identical to potential,
IgE-binding linear epitopes of allergens. BMC
Structural Biology, 2 8.
15Kleter, G.A. and A.C.M Peijnenburg. 2002.
Screening of transgenic proteins expressed in
transgenic food crops for the presence of short
amino acid sequences identical to potential,
IgE-binding linear epitopes of allergens. BMC
Structural Biology, 2 8.
16Kleter, G.A. and A.A.C.M Peijnenburg. 2002.
Screening of transgenic proteins expressed in
transgenic food crops for the presence of short
amino acid sequences identical to potential,
IgE-binding linear epitopes of allergens. BMC
Structural Biology, 2 8.
- Only a limited number of identical stretches
shared by transgenic proteins (papaya ringspot
virus coat protein, acetolactate synthase GH50,
and glyphosate oxioreductase) and allergenic
proteins could be identified as (part of)
potential linear epitopes. . . The positive
outcomes of this approach warrant further
clinical testing for potential allergenicity.
17Gendel, S.M. 1998b. The use of amino acid
sequence alignments to assess potential
allergenicity of proteins used in genetically
modified foods. Advances in Food and Nutrition
Research, 42 44-61.
- although it is clear that some amino acid
residues are critical for specific binding, some
conservative substitutions may not affect
allergenicity. Therefore, it may be prudent to
treat sequence matches with a high degree of
identity that occur within regions of similarity
as significant even if the identity does not
extend for eight or more amino acids. For
example, the similarity between Cry1A(b) and
vitellogenin might be sufficient to warrant
additional evaluation (Gendel, 1998b 60).
18Fares, NH AK El-Sayed. 1998. Fine structural
changes in the ileum of mice fed on
delta-endotoxin-treated potatoes and transgenic
potatoes. Natural Toxins 6 219-233.
- Bt-potatoes and Bt-toxin (Cry 1) caused
disruption, multinucleation, swelling, increased
degradation of ileal (gut) surface cells in rats.
Effect worse with Bt-toxin - These effects demonstrate that Bt-toxin survives
digestion in functionally and immunologically
active form
19Fares, NH AK El-Sayed. 1998. Fine structural
changes in the ileum of mice fed on
delta-endotoxin-treated potatoes and transgenic
potatoes. Natural Toxins 6 219-233.
- These changes may suggest that
delta-endotoxin-treated potatoes resulted in the
development of hyperplastic cells in the mice
ileum. Although mild changes are reported in the
structural configuration of the ileum of mice fed
on transgenic potatoes, nevertheless, thorough
tests of these new types of genetically
engineered crops must be made to avoid the risks
before marketing. (Fares and Sayed, 1998 219)
20Vazquez-Padron, R.I., Moreno-Fierros, L.,
Neri-Bazan, L., de la Riva, G.A. and R.
Lopez-Revilla. 1999b. Bacillus thuringiensis
Cry1Ac protoxin is a potent systemic and mucosal
adjuvant. Scandinavian Journal of Immunology 49
578-584
- We conclude that Cry1Ac is a mucosal and
systemic adjuvant as potent as CT cholera toxin
which enhances mostly serum and intestinal IgG
antibody responses (Vazquez-Padron et al.,
1999b pg. 578). - Cry1Ac is potent stimulator of immune system
- Cry1Ac survives digestion
21Vazquez-Padron, R.I., et al. 2000b. Cry1Ac
protoxin from Bacillus thuringiensis sp. kurstaki
HD73 binds to surface proteins in the mouse small
intestine. Biochemical and Biophysical Research
Communications 271, pp. 54-58
- we demonstrated that Cry1Ac protoxin (pCry1Ac)
binds to the mucosal surface of the mouse small
intestine . . . six pCry1Ac-binding polypeptides
present in brush border membrane vesicles
isolated from the small intestine. Moreover,
this protein induced in situ temporal changes in
the electrophysiological properties of the mouse
jejunum. The data obtained indicate a possible
interaction in vivo of Cry proteins with the
animal bowel which could induce changes in the
physiological status of the intestine
(Vazquez-Padron et al., 2000b 54).
22Vazquez-Padron, R.I., et al. 2000b. Cry1Ac
protoxin from Bacillus thuringiensis sp. kurstaki
HD73 binds to surface proteins in the mouse small
intestine. Biochemical and Biophysical Research
Communications 271, pp. 54-58
- We think that previous to commercialization of
food elaborated with self-insecticide transgenic
plants it is necessary to perform toxicological
tests to demonstrate the safety of Cry1A proteins
for the mucosal tissue and for the immunological
system of animals (Vazquez-Padron et al., 2000b
58).
23Bernstein, et al. 1999. Immune responses in
farm workers after exposure to Bacillus
thuringiensis pesticides. Environmental Health
Perspectives, 107(7) 575-582
- Scientists did study on farm workers in onion
fields in Ohio, US that were exposed to Bt sprays - reactivity IgE antibodies to the Btk
pro-delta-endotoxin was encountered in 2 of 123
workers sensitized by the respiratory route . . .
future clinical assessment of this possibility
is now feasible because of the availability of
reliable Bt skin and serologic reagents developed
during the course of this investigation
(Bernstein et al., 1999 pg. 581).
24Bernstein, et al. 2003. Clinical and laboratory
investigation of allergy to genetically modified
foods. Environmental Health Perspectives,
111(8) 1114-1121.
- Workers in agricultural and food preparation
facilities have potential inhalation exposure to
plant dusts and flours. In 1999, researchers
found that migrant health workers can become
sensitized to certain Bt spore extracts after
exposure to Bt spraying. Thus, the potential for
occupational and consumer risks needs to be
assessed.
25Impact of Bt cotton on farmers health (in
Barwani and Dhar District of Madhya Pradesh) Dr.
Ashish Gupta et al. Investigation Report Oct.
Dec. 2005www.gmwatch.org/print-archive2.asp?arcid
6265
- Surveyed 5 villages, talked to people with
symptoms and exposure to Bt cotton N 23 - All had skin symptoms, primarily itching (23),
redness (19), or eruptions (20). The symptoms
tended to occur on face (17), hands (15), feet
(11) - Almost half (11) had eye symptomsitching,
redness and/or swelling - About 40 (9) had upper respiratory tract
symptoms runny nose and/or excessive sneezing - Almost 90 had moderate (10) or severe symptoms
(10)
26Impact of Bt cotton on farmers health (in
Barwani and Dhar District of Madhya Pradesh Dr.
Ashish Gupta et al. Investigation Report Oct.
Dec. 2005www.gmwatch.org/print-archive2.asp?arcid
6266
- Symptoms overwhelmingly on exposed parts of body
(face, hand, feet, neck, eyes and respiratory
tract). Only 1 of 23 had symptoms only on
covered parts of body (14 exposed body parts
only, 8 both) - Almost 80 (18) exposed in cotton field, 4
exposed at home - Almost 74 (17) directly involved in picking
cotton - People that symptoms increased in severity when
they continued to work in fields and decreased
when they stopped work - Symptoms started within last two years, when Bt
cotton was introduced
27Impact of Bt cotton on farmers health (in
Barwani and Dhar District of Madhya Pradesh Dr.
Ashish Gupta et al. Investigation Report Oct.
Dec. 2005www.gmwatch.org/print-archive2.asp?arcid
6266
- Ginning factory
- Owner noted that most of the farmers and
labourers were having skin related problems due
to Bt cotton - Detailed interview with 6 workers in different
ginning factories found all had itching problems
on exposed parts of body (hands, legs, face), and
2 were having eruptions on body - Workers had been in factory from 2 7 years, but
symptoms only began last year, with introduction
of Bt cotton
28MON 863
- MON 863Monsanto Bt maize for corn rootworm (with
Cry3Bb1) - Approved in US and in EU
- Monsanto submission revealed significant effects
on organs and blood parameters (Séralini et al.
2007. New analysis of a rat feeding study with a
genetically modified maize reveals signs of
hepatorenal toxicity. Arch Environ Contam
Toxicol, 52 596-602.) - Increased basophils, lymphocytes and white
blood cells. Decreased reticulocytes - Decreased kidney weight
- Increased blood sugar
29Vendômois, JS, Roullier, F, Cellier, D and GE
Séralini. 2009. A comparison of the effects of
three GM corn varieties on mammalian health.
International Journal of Biological Sciences,
5(7) 706-726.
- Study obtained Monsantos submission to EU for 3
GE corn varieties (NK 603, MON 810, MON 863) and
reanalyzed all the data - Approximately 60 different biochemical
parameters were classified per organ and measured
in serum and urine after 5 and 14 weeks of
feeding.
30Vendômois, JS, Roullier, F, Cellier, D and GE
Séralini. 2009. A comparison of the effects of
three GM corn varieties on mammalian health.
International Journal of Biological Sciences,
5(7) 706-726.
- Our analysis clearly reveals for the 3 GMOs new
side effects linked with GM maize consumption,
which were sex- and often dose-dependent.
Effects were mostly associated with the kidney
and liver, the dietary detoxifying organs,
although different between the 3 GMOs. Other
effects were also noticed in the heart, adrenal
glands, spleen and haematopoietic system. We
conclude that these data highlight signs of
hepatorenal toxicity, possibly due to the new
pesticides specific to each GM corn. In
addition, unintended direct and indirect
metabolic consequences of the genetic
modification cannot be excluded.
31Zolla, L. et al. 2008. Proteomics as a
Complementary Tool for Identifying Unintended
Side Effects Occurring in Transgenic Maize Seeds
As a Result of Genetic Modifications. Journal of
Proteome Research, 7 1850-1861.
- Proteomics is the study of expressed proteins.
This is good way to detect unintended effects
associated with GE, particularly the disruptive
effects due to the random insertion of transgene - Superior study design GE maize (MON810) and
near isoline grown side-by-side in growth
chamber, to control for environmental effects
32Zolla, L. et al. 2008. Proteomics as a
Complementary Tool for Identifying Unintended
Side Effects Occurring in Transgenic Maize Seeds
As a Result of Genetic Modifications. Journal of
Proteome Research, 7 1850-1861.
- Results 43 proteins resulted up- or
down-regulated in transgenic seeds with respect
to their controls (T06 vs WT06), which could be
specifically related to the insertion of a single
gene into a maize genome by particle
bombardment. (pg. 1850). Of these 43 proteins,
14 were down-regulated, 13 up-regulated, 9 shut
off and 7 newly expressed. - Interestingly, a newly expressed spot (SSP 6711)
corresponding to 50 kDa gamma zein, a well-known
allergenic protein, has been detected. Moreover,
as a major concern, a number of seed storage
proteins (such as globulins and vicilin-like
embryo storage proteins) exhibited truncated
forms having molecular masses significantly lower
than the native ones. (pg. 1855)
33Finamore, A et al. 2008. Intestinal and
Peripheral Immune Response to MON810 Maize
Ingestion in Weaning and Old Mice. Journal of
Agricultural and Food Chemistry
- Well designed study MON810 and near isoline
grown simultaneously in neighboring fields in
Landriano, Italy, to control for environmental
effects - This study evaluated the gut and peripheral
immune response to genetically modified (GM)
maize in mice in vulnerable conditions. Weaning
and old mice were fed a diet containing MON810 or
its parental control maize . . . for 30 and 90
days. . . As compared to control maize, MON810
maize induced alterations in the percentage of T
and B cells and of CD4, CD8, ?dT, and RT
subpopulations of weaning and old mice fed for 30
or 90 days, respectively, at the gut and
peripheral sites. An increase of serum IL-6,
IL-13, IL-12p70, and MIP-1 cytokines involved in
allergenic and inflammatory response after
MON810 feeding was also found. These results
suggest the importance of the gut and peripheral
immune response to GM crop ingestion as well as
the age of the consumer in the GMO safety
evaluation.
34Velirimov et al. 2008. Biological effects of
transgenic maize NK603xMON810 fed in long term
reproduction studies in mice.
- Very carefully designed Austrian long-term
feeding study. The non-GE maize control was a
near isogenic line. Both control and GE maize
were grown in adjacent fields in Canada in the
same year (2005, 2007), to control for
environmental effects. Large sample sizes were
used to detect more subtle adverse effects. - Major result statistically significant adverse
reproductive effects shown in the reproductive
assessment by continuous breeding (RACB) study.
RACB is a feeding study whereby a pair of mice
are fed GM maize for 140 days, during which time
the female is bred so that she delivers 4
litters. RACB puts mice under stress making it
easier to detect adverse effects.
35Velirimov et al. 2008. Biological effects of
transgenic maize NK603xMON810 fed in long term
reproduction studies in mice.
- From 24 pairs assigned to the ISO and GM group,
all females of the ISO group (100) delivered 4
litters. In the GM group the number of deliveries
declined with time. In the 4th litter only 20
deliveries occurred (p0.055). The average number
of pups born was always lower in the GM group but
not significant before the 3rd delivery. There
were significantly fewer pups born in the GM
group in the 3rd (p 0.011) and 4th (p0.010)
delivery and weaned in the 4th litter (p0.025).
Regarding all deliveries per group more pups were
born in the ISO than in the GM group (1035 versus
844). Furthermore females of the GM group always
had smaller litters (n lt 8) as compared to
females of the ISO group.
36Benbrook, C. 2004. Genetically engineered crops
and pesticide use in the United States The
first nine years. At http//www.biotech-info.ne
t/Full_version_first_nine.pdf
37Benbrook, C. 2004. Genetically engineered crops
and pesticide use in the United States The
first nine years. At http//www.biotech-info.ne
t/Full_version_first_nine.pdf
38Benbrook, C. 2009. Genetically engineered crops
and pesticide use in the United States The
first thirteen years.
- During first 9 years, pesticide use on
genetically engineered crops was increased by a
total of 122 million pounds. - Update on the Benbrooks 2004 paper Bt corn
and cotton has reduced insecticide use by 56
million pounds, but herbicide tolerant crops have
increased pesticide use by 383 million pounds,
for an overall 327 million pounds increase over
the 13 years. - So, for 1996-2004, 122 million pounds more
pesticide was used on GE compared to non-GE
crops. For 2005-2008, an additional 205 million
extra pounds were applied.
39Wang, S., Just, D.R. and P. Pinstrup-Andersen.
Tarnishing Silver Bullets Bt technology
adoption, bounded rationality and the outbreak of
secondary pest infestations in China. Paper
presented at American Ag. Econ. Assoc. annual
meeting, Long Beach, CA, 22-26 July, 2006
- Household survey of 481 farmers, 20 villages, 5
provinces Hebei, Shandong, Henan, Anhui, Hubei - Results for 2004
- Average expenditure on pesticides was same (
US101/ha) between Bt and non-BT farmers - Bt farmers spend 46 less on bollworm pesticide,
but spend 40 more on pesticides for secondary
pest(s), compared to non-Bt farmers - Main secondary pest mirids
- GM cotton seeds cost 3 times more than non-Bt
cotton, so Bt farmers make less money than non-Bt
farmers - Results markedly different from data from 1999,
2000, 2001
40Wang, S., Just, D.R. and P. Pinstrup-Andersen.
Tarnishing Silver Bullets Bt technology
adoption, bounded rationality and the outbreak of
secondary pest infestations in China. Paper
presented at American Ag. Econ. Assoc. annual
meeting, Long Beach, CA, 22-26 July, 2006
41Wang, S., Just, D.R. and P. Pinstrup-Andersen.
Tarnishing Silver Bullets Bt technology
adoption, bounded rationality and the outbreak of
secondary pest infestations in China. Paper
presented at American Ag. Econ. Assoc. annual
meeting, Long Beach, CA, 22-26 July, 2006
42Wang, S., Just, D.R. and P. Pinstrup-Andersen.
Tarnishing Silver Bullets Bt technology
adoption, bounded rationality and the outbreak of
secondary pest infestations in China. Paper
presented at American Ag. Econ. Assoc. annual
meeting, Long Beach, CA, 22-26 July, 2006
43Do GE crops reduce pesticide use?
- farmers have rotated RR crops, usually soya and
maize, to the point that the weeds themselves are
now Roundup resistant, which has resulted in much
higher applications of Roundup along with a host
of other chemicals. Nathalie Moll, EuropaBio.
In GM crops Biotech agricultureTime to take
GM seriously, Ethical Corporation, February 7,
2008 At www.ethicalcorp.com/content.asp?ContentI
D5684
44Richard, S. et al. 2005. Differential effects
of glyphosate and Roundup on human placental
cells and aromatase. Environmental Health
Perspectives, 113(6) 716-720.
- Exposure of male farmers in Ontario, Canada to
glyphosate-based herbicides was associated with
increase in miscarriage and premature birth in
farm families (Savitz et al. 1997. Male
pesticide exposure and pregnancy outcome. Am J
Epidemiology, 146 1025-1036.) this study tried
to look at possible mechanisms. - Design incubated human placental JEG3 cells
with various concentrations of Roundup (up to 2)
or equivalent concentrations of glyphosate. Cell
viability was measured after 18, 24, and 48
hours. Aromatase (which regulates estrogen
synthesis) levels were measured after 1 hour and
18 hours. - Results 2 Roundup and an equivalent
concentration of glyphosate killed 90 of the
JEG3 cells after 18 hours incubation. Median
lethal dose for Roundup (0.7) was approximately
1.8 times lower than for glyphosate. Viability
of cells exposed to glyphosate was considerably
reduced when just 0.1 Roundup was added.
45Richard, S. et al. 2005. Differential effects
of glyphosate and Roundup on human placental
cells and aromatase. Environmental Health
Perspectives, 113(6) 716-720. Contd
- Results After 1 hour incubation with Roundup,
aromatase activity increased by 40. After 18
hours, synthesis was inhibited, with a median
inhibiting concentration (IC50) of 0.04, perhaps
reflecting an effect on aromatase gene
expression. No effect was seen with glyphosate
alone. - In sum, study showed that effect of Roundup on
cell viability increased with time and was
obtained with concentrations of Roundup 10 times
lower than those recommended for agricultural
use. Roundup also disrupted aromatase activity
at concentrations 100 times lower than those used
in agriculture.
46Eriksson, S., Hardell, L et al. 2008. Pesticide
exposure as risk factor for non-Hodgkin lymphoma
including histopathological subgroup analysis.
Int. J. of Cancer, 123 1657-1663.
- Design Population based case-control study.
910 NHL cases (male and female age 18-74 years,
living in Sweden, from December 1, 1999, to April
30, 2002) and 1016 controls. - Results Exposure to phenoxyacetic acids yielded
odds ration (OR) 2.04 (95 confidence interval
CI 1.18-2.51). Exposure to glyphosate gave OR
of 2.02, 95 CI 1.10-3.71 and with gt10 years
latency period OR was 2.26, 95 CI 1.16-4.40. - Previous study involving pooled analysis of 2
Swedish case-control studies showed OR for
glyphosate of 3.04 (95 CI 1.08-8.52). (Hardell,
L., Eriksson, M and M. Nordstrom. 2002.
Exposure to pesticides as risk factor for
non-Hodgkins lymphoma and hairy cell leukemia
pooled analysis of two Swedish case-control
studies. Leukemia Lympoma, 1043-1049) - Conclusion our study confirmed an association
between exposure to phenoxyacetic acids and NHL
and the association with glyphosate was
considerably strengthened.
47Conclusion
- 1. US FDA does not require preapproval safety
assessments - 2. The endotoxins in Bt crops raise issues of
allergenicity and immunogenicity - 3. Feeding studies have found unexpected adverse
effects - 4. Between 1995-2009, GE crops in US have
increased use of herbicides, particularly
glyphosate, by 383 million pounds and decreased
insecticide use by 56 million pounds - 5. Roundup appears to be an endocrine disruptor
and has been linked to increased risk of
Non-Hodgkins lymphoma
48 Codex Alimentarius Principles for the Risk
Analysis of Foods Derived from Modern
Biotechnology (CAC/GL 44 2003)
- 18. Risk managers should take into account the
uncertainties identified in the risk assessment
and implement appropriate measures to mange these
uncertainties - 19. Risk management measures may include, as
appropriate, food labelling, conditions for
market approval and post-market monitoring - (paras 18, 19 CAG/GL 44-2003)
49 Codex Alimentarius Guideline for Conduct of
Food Safety Assessment of Foods Derived from
Modern Biotechnology (CAC/GL 45 2003)
- Unintended effects due to genetic modification
may be subdivided into two groups those that
are predictable and those that are unexpected
. . . A variety of data and information are
necessary to assess unintended effects because no
individual test can detect all possible
unintended effects or identify, with certainty,
those relevant to human health. These data and
information which considered in total, provide
assurance that the food is unlikely to have an
adverse effect on human health italics added
(paras 16 and 17, CAG/GL 45-2003)
50 Codex Alimentarius Guideline for Conduct of
Food Safety Assessment of Foods Derived from
Modern Biotechnology (CAC/GL 45 2003)
- Molecular biological and biochemical techniques
(that) can also be used to analyse potential
changes at the level of gene transcription and
message translation that could lead to unintended
effects (para 16, CAG/GL 45-2003)
51 Unintended Effects
- Belgian scientists looked at molecular
characterization of 6 transgenic crops 3 Bt
maizes herbicide tolerant maize (LibertyLink
maize) glyphosate tolerant soybeans, and a
canola engineered for male sterility - In all but canola, structure of transgenic
inserts differed between a companys initial
submission and subsequent studies. Differences
involved rearranged inserts, partial copies of
genes inserted, multiple copies of transgenes
inserted, scrambling of DNA near the border of
the transgenic inserts, etc., instability and/or
more likely to result in unintended effects. - Scientists recommend that further analysis
should be done to determine the presence of
chimaeric open reading frames in the border
integration sequences, e.g. are any unexpected
proteins being produced?
52 Codex Alimentarius Annex on the Assessment of
Possible Allergencity of the Guideline for the
Conduct of Food Safety Assessment of Foods
Derived from Recombinant-DNA Plants
- 2. At present, there is no definitive test that
can be relied upon to predict allergic response
in humans to a newly expressed protein (para 2,
Annex, CAG/GL 45-2003)