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WARNING
SIGNS
Potential Health Risks
of Genetically Engineered Organisms in Animal Feed
Greenpeace
International, November 2000
The string of recent scandals related to the way we feed animals
is long. Most recently, the governments of France and Italy
have reacted to BSE (mad cow disease) by banning the use of
bone and animal meal. Dioxins have been found in chicken feed
in Belgium and in France, sewage has been found in animal
feed. Hormones and antibiotics are standard components in
the high-energy feed mixtures for fast growth and maximum
performance of animals raised by industry and farmers.
There have been no fatal
or clinical incidences or major problems with the use of genetically
modified soya beans and maize or their derivatives in animal
feed so far. However there is a growing list of warning signs
and increasing evidence that there was no proper testing of
these new products, which are now fed to animals in large
quantities both in North America and Europe for the third
consecutive year.
Antibiotic
Resistance
Genetically modified
organisms (GMOs) fed to animals today contain genes which
make them resistant to antibiotics used for the treatment
of diseases in both humans and animals. These genes had been
introduced by the genetic engineers as markers for technical
purposes. They could severely undermine the effective treatment
of diseases if the antibiotic resistance is transferred to
bacteria which are harmful to human and animal health.
Scientists (1), biosafety
committees and governments have opposed the introduction of
GMOs with antibiotic resistance genes. Norway banned them
altogether. Austria and Luxembourg have banned Novartis' maize,
Switzerland did not even allow a field experiment with a GE
potato because it contained a kanamycin resistance gene. From
the British Medical Association (2) to the European Parliament
a variety of institutions have demanded a ban of antibiotic
resistance genes in GMOs.
Precaution clearly demands
that any use of antibiotic resistance genes be prohibited.
There is no reason to risk any further health threats from
antibiotic resistance to serve short term industry interests.
Transfer of
DNA from GMOs to animals or bacteria
There is evidence that
DNA from food uptake can survive in animal guts and can even
be traced in somatic cells. Such foreign DNA could be traced
up to 24 hours after feeding in spleen and liver cells (3).
Recently nutrition scientists
of the Friedrich-Schiller-University in Jena, Germany (4)
informed that they have detected DNA fragments of genetically
engineered corn in the organs and meat of chicken fed with
such corn. What kind of effects this might have when consumed
by humans is unclear. These findings have not yet been published
in peer reviewed science journals.
Other research indicates
that DNA released from bacteria or food sources within the
mouth can be transfered to other oral bacteria (5).
Allergies
Genetic engineering
can confer new allergic potential to crops. A famous example
is a soybean genetically engineered with a gene from a Brazil
nut. Tests on blood taken from individuals allergic to Brazil
nuts unexpectedly revealed that they had a similar allergic
reaction to the GE soybean (6).
The US Environmental Protection
Agency did not approve the genetically engineered maize variety
"Starlink" of Aventis for human consumption as there is concern
about the allergic potential of a toxin it produces (Bacillus
thuringiensis Cry9C). There is evidence that Cry9C is heat
stable and resistant to degradation in gastric juice, two
important indicators of potential allergenicity. Effects of
Cr9C on animals and it's fate in animal products remain to
be examined.
Roundup Ready
Soybeans have unexpected properties
In a recent study (7),
US scientists discovered substantial differences in the levels
of phytoestrogens between soy beans that are genetically engineered
were treated with Monsantos herbicide "Roundup" and conventional
soy. Phytoestrogens are hormone-like substances in plants
and are believed to have a positive health effect. Phytoestrogen
levels in genetically engineered soy beans were found to be
reduced. This is clear evidence that conventional and genetically
engineered soya beans are substantially different.
"As a scientist,
I wouldn't drink milk from cows fed GM maize..."
The weakness of the
scientific basis for genetically engineered crops became obvious
at a public hearing in Britain on Chardon LL, another herbicide
tolerant maize variety for livestock feed, from the "Starlink"
producer Aventis.
At the hearing Professor
Bob Orskov, Director of the International Feed Resource Unit
in Aberdeen, Scotland, one of the country's leading experts
on ruminant nutrition, stated that the scientific case put
forward for this GE maize was not adequate; testing was insufficient
both in terms of time and variety of parameters. "if the GM
maize was approved for commercial growing in the UK, then
people would be justified in turning their back on consuming
milk derived from it". He added: "As a scientist, I wouldn't
drink milk from cows fed GM maize with the present state of
knowledge." Another expert witness, Dr Vyvyan Howard, who
is head of the Foetal and Infant Toxico-Pathology group at
the University of Liverpool, told the hearing: "My interpretation
is that this GM maize has not been tested thoroughly." He
said after examining data from the biotechnology company Aventis,
which makes the GM maize, there appeared to be "statistically
significant" differences between the fat, protein and fibre
composition of its "Chardon LL" GM strain and non-GM varieties
(8).
While industry often
argues that GMOs in animal feed were extensively tested for
safety there are few peer reviewed scientific publications
available on longer term animal feeding tests with GMOs (9).
References
(1) Pechère, J-C. (1998)
Concerns about the presence of a ß-lactamase gene in
a transgenic maize. Newsletter of the International Society
of Chemotherapy, December 1998, p16
Patrice Courvalin, Plantes transgéniques et antibiotiques,
La Recherche No. 308, Mai 1998
ACRE Annual Report No 4:
1996/97. Department of the Environment, Transport and the
Regions
(2) British Medical Association,
Board of Science and Education, The Impact of Genetic Modification
on Agriculture, Food and Health, An Interim Statement, May
1999, ISBN: 07279 1431 6
(3) Schubbert R., Renz D., Schmitz
B., and Doerfler W. (1997), Foreign (M13) DNA ingested by
mice reaches peripheral leukocytes, spleen, and liver via
the intestinal wall mucosa and can be covalently linked to
mouse DNA, Proc. Natl. Acad. Sci. USA, Vol. 94, pp. 961-966
(4) Prof. Dr. Gerhard Jahreis
and Dipl.-troph. Jana Kraft, Friedrich-Schiller-University
in Jena, Germany., press release of the University of Jena,
3.11.2000 , Contact: b6jage@rz.uni-jena.de, Friedrich-Schiller-University,
Fuerstengraben 1, D-07743 Jena, Tel.: +49-3641-931031 Fax:
+49-3641-931032
(5) Mercer D., Scott K., Bruce-Johnson
A., Glover L. and Flint H. (1999) Fate of Free DNA and Transformation
of the Oral Bacterium Streptococcus gordonii DL1 by Plasmid
DNA in Human Saliva, Applied and Environmental Microbiology,
Vol 65, No. 1, p 6-10
(6) Nordlee, J.D., Taylor S.L.,
Townsend, L.X, Thomas, L.A., & Bush, R.K. (1996) Identification
of a Brazil nut Allergen inTransgenic
Soybeans, New England Journal of Medicine, Vol. 334 (11) p.
688.
(7) Lappé, M.A., Bailey,
E.B., Childress, C.C. & Setchell, K.D.R. (1999) Alterations
in clinically important phytoestrogens in genetically modified,
herbicide-tolerant soybeans. Journal of Medicinal Food, Vol.
1
(8)The Independent (London),
October 19, 2000, Pg. 8, "INQUIRY WARNED OVER MILK FROM GM-FED
COWS"
(9) a) RR soybeans by Monsanto,
1996: The feeding value of soybeans fed to rats, chickens,
catfish and dairy cattle is not altered by genetic incorporation
of glyphosate tolerance, Hammond, Bruce G.; Vicini, John L;
et al, ‘The Journal of Nutrition’ , Vol. 126, ps. 717-727)
b) Event 176 Bt corn by
Novartis, 1998: 38 day feeding to chickens. Brake, J. and
D. Vlachos. 1998. Evaluation of transgenic event 176 "Bt"
corn in broiler chickens. Poultry Science 77: 648-653.
c) RR corn (GA 21) by Monsanto,
2000: 38-40 day feeding in chickens. Glyphosate-tolerant corn:
The composition and feeding value of grain from glyphosate-tolerant
corn is equivalent to that of conventional corn (Zea mays
L.). Sidhu, R.S., B.G. Hammond, R.L. Fuchs, J.-N. Mutz, L.R.
Holden, B. George, and T. Olson, Journal of Agricultural and
Food Chemistry 48: 2305-2312
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