Among the next generation of genetically modified (GM) plants are
those that are engineered to produce elevated levels of nutritional
molecules such as vitamins, omega-3 fatty acids, and amino acids.
Based upon the U.S. current regulatory scheme, the plants and their
products may enter our food supply without any required safety
testing. The potential risks of this type of GM plant are discussed in
the context of human health, and it is argued that there should be
very careful safety testing of plants designed to produce biologically
active molecules before they are commercially grown and consumed. This
will require a mandatory, scientifically rigorous review process.
For the full article see here:
JOURNAL OF MEDICINAL FOOD
J Med Food 11 (4) 2008
schubert@salk.edu
CONCLUSIONS
The above paragraphs summarize published data that clearly show the
following: (1) Compounds structurally related to a common small
molecule can have a lethal effect when present as even a minor
contaminant in a food supplement. (2) The GM enhancement of a
metabolic pathway by the overexpression of genes for that pathway can
have unpredictable consequences in the form of synthesizing a toxin.
(3) Finally, in the case of golden rice, it is argued that
biologically active compounds derived from aberrant plant carotenoid
synthesis could have profound effects on human development. Similar
arguments can be made for NEP-derived fatty acids that are directly
incorporated into brain lipids and about NEPs overproducing vitamin E.
Aberrant fatty acid composition of brain lipids is implicated in
Alzheimerís disease, 45,46 and vitamin E has a role similar to RA in
mammalian development. 47 The excess consumption of a nutrient can
also have negative effects. For example, a clinical trial with vitamin
E supplementation showed that a relatively small dose increased the
risk of heart failure, 48 and smokers who supplemented their diet with
-carotene had an increased risk of lung cancer. 49 Therefore, there is
a potential for nutrient toxicity in NEPs because upper tolerable
levels of many nutrients are not well established (p. 107) 35 and are
likely to vary between individuals and lifestyles.
The information presented here shows that not only the potential harm
of the product should be considered for risk assessment, but the GM
process itself. The data clearly invalidate the argument that "the
regulatory trigger for risk assessment should be based upon the
physical features of the product rather than the process by which the
product was generated." 50 While it is true that traditional breeding
methods can give rise to potentially hazardous products, the most
recent assessment of GM food safety by the National Research Council
35 stated that GM ìhas a higher probability of producing unanticipated
changes than some genetic modification methods" (p. 118), but it
curiously concludes by stating that the risk of GM technology is no
greater than conventional breeding methods. There are, in fact, no
data comparing the food safety profiles of GM versus conventional
breeding, and the ubiquitous argument that since there is no evidence
that GM products make people sick, they are safe (see, for example,
McHughen and Smyth, 50 Bradford et al., 51 and Miller et al. 52) is
both illogical and false. There are, again, simply no data or even
valid assays to support this contention. 53 Without proper
epidemiological studies, most types of harm will not be detected, and
no such studies have been conducted.
The necessity of labeling all GM products and particularly NEPs is
therefore critical if there is any hope of monitoring adverse health
consequences due to their consumption. For example, it would have been
impossible to identify the source of the toxic tryptophan supplement
if the product were not traceable through labeling. It follows that
before NEPs producing biologically active molecules such as -carotene,
omega-3 fatty acids, or vitamin E are introduced into the food chain,
great care must be taken to do rigorous, multigenerational animal
safety assessments with the hope of identifying risks to health (for
methods, see, for example, the 2007 publication by the National
Toxicology Program 54 and Pusztai and Bardocz 55). In addition, the
products must be labeled and traceable, and the unpredictable and
unintended metabolic changes that may occur in NEPs require the
thorough testing of the entire edible portion of the plant, not just
the designated product as is almost always done by biotech companies.
56 To date there is essentially no multigenerational animal safety
testing published for GM plants 55,57 and no required labeling in the
United States for any GM product. In an excellent review of our
current GM regulatory process, Mandel 58 concluded that for
second-generation GM products, like NEPs, "it is necessary to
establish a comprehensive, efficient and scientifically rigorous
regulatory system." As discussed herein there are very valid
scientific concerns to support this conclusion.
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