GENTECH archive 8.96-97


Importation of Ciba-Geigy's Bt Maize Is Scientifically Indefensible

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Date:    Thu, 17 Apr 97 17:26:19 -0500 
From: (Richard Wolfson)
Subject: BT Corn issue

Importation of Ciba-Geigy's Bt Maize Is Scientifically Indefensible

John Fagan, Ph. D.

The European Commission is considering whether or not to allow Ciba-Geigy's
genetically engineered maize to be imported into the European Community
from the US for human and animal consumption.

There is tremendous pressure from the US government and biotechnology
industry to allow the importation of this product, and there have even been
intimations that refusal to admit this genetically modified maize into the
European Community might have broader implications for trade relations with
the US.

Important as healthy trade relations with the US are, there are other
issues that are highly relevant to the importation of this maize. In
particular, there are serious concerns tha this product may pose risks to
consumer health and to the environment.

If the Commission fails to take these issues into account in their
deliberations on whether or not to admit Bt maize into the European
Community, it will have favored the business interests of a single
multinational corporation over the health, welfare, and fundamental rights
of millions of European citizens.

There are four scientific reasons to exclude Bt maize from Europe. We will
first introduce all of these briefly and then elucidate each in more detail
in subsequent sections. 1.      There is a virtual certainty that the
importation of this product will lead to the generation of pathogenic
bacteria that are resistant to the antibiotic ampicillin. 2.      Bt maize
constitutes a significant risk to the health of consumers because it has
not been tested thoroughly enough to assure (a) that it does not contain
unanticipated allergens or toxins, and (b) that its nutritional value has
not been reduced in unexpected ways. 3.      The US government and the US
biotechnology industry are demanding to import this maize unlabeled and
mixed with non-genetically modified maize. This deprives consumers of the
information needed to choose for themselves whether to accept the health
risks associated with eating these inadequately tested foods. This also
deprives consumers of their fundamental right to make informed purchasing
choices. 4.      Scientific evidence indicates that the cultivation of Bt
maize will lead to the emergence of insect pests that are resistant to the
Bt toxin. This disruption of the ecosystem is inherently undesireable, and
it is also detremental to agriculture in the long run. It will not only
make Ciba-Geigy's Bt corn variety obsolete, but it will also deprive
organic and biological farmers of a valuable tool for pest control-Bt toxin
extracted from natural Bacillus thuringiensis. Allowing Ciba-Geigy's Maize
to be imported into Europe sends a green light to industry that it is
acceptable to ignore serious environmental, ecological, and agricultural
threats in the development and commercialization of genetically engineered

The following sections presents these points in more detail.

Antibiotic Resistance Not only has the gene for ampicillin resistance been
introduced into Ciba-Geigy's Bt maize, but in this maize variety, the
ampicillin resistance gene is still linked to bacterial regulatory
sequences, called promoter sequences. These promoter sequences make this
gene highly active in bacteria. It is well known that many kinds of
bacteria readily pick up genes present in their environment and incorporate
them into their own DNA. Due to the presence of these promoter sequences,
it is highly likely that any bacterium that happens to pick up this gene
will express ampicillin resistance. Thus it is virtually certain that the
use of Ciba-Geigy's Bt corn will generate ampicillin resistant bacteria.

The digestive tracts of both humans and livestock contain large populations
of benign bacteria. Transfer of the ampicillin gene to any one of those
bacterial strains will secondarily generate ampicillin resistant pathogenic
bacteria, as well. Whn humans or livestock eat Bt maize the ampicillin
resistance gene will be present in the digestive tract. This gene will be
picked up by intestinal bacteria, conferring on them resistance to that
antibiotic. Then, when at some later time that person or animal becomes
infected with pathogenic bacteria, the ampicillin resistance gene can
readily be transferred to that pathogen from the benign intestinal bacteria
that initially picked it up.

The result will be an ampicillin-resistant pathogen, which physicians will
be unable to combat with ampicillin. Already the over-use and misuse of
antibiotics has generated superbugs, pathogens resistant to a wide range of
antibiotics. Commercialization of Bt maize will accelerate this process,
making the problem even worse.

Proponents of Bt maize do not dispute that its use can contribute to
antibiotic resistance in pathogens. Instead, they attempt to justify this
by claiming that antibiotic resistant microorganisms are already being
generated by other mechanisms, such as incorrect use of antibiotics, and
therefore the added contribution of Bt maize need not be taken seriously.

We hold to the old adage that two wrongs do not make a right. It is true
that antibiotic resistant pathogens are being generated by other
mechanisms. However, we seriously question the wisdom of contributing to
this trend by introducing widely a new mechanism that will surely generate
antibiotic resistance.

Furthermore, claims that Bt maize will make only a small contribution to
the process of creating antibiotic resistant pathogens, compared to other
mechanisms, is pure speculation. There is no quantitative evidence that
this is the case. Especially if genetically engineered Bt crops become
widely used as animal feed, the contribution could be very large.

Health Risks of Bt Maize Ciba-Geigy's Bt maize has met the current
requirements for safety testing required by the US government and by the
European Union. However, a careful scientific evaluation of the tests
actually performed indicates that these tests have not been sufficient to
assure that Bt maize is safe to eat. In the US, all testing of genetically
engineered foods is voluntary. Manufacturers are not required by law to
test these foods before placing them on the market. In Europe, testing is
not voluntary. However, the tests required are never-the-less inadequate to
detect all potential hazards in genetically engineered foods.

Two interrelated factors contribute to these inadequacies. First, the
process of genetic engineering is not completely reliable and controlled.
It can, therefore introduce unforeseen genetic changes into the
food-producing organism, which can, in turn, lead to changes in the
characteristics of the food that cause it to contain unexpected allergens
or toxins, or be reduced in nutritional value. In light of this scientific
fact, one might expect that regulatory agencies would have already
established a highly rigorous system for testing these novel foods that is
designed to detect those that could jeopardize health. Yet, the safety
testing currently required falls far short of this standard. It is not
capable of detecting the full range of unforeseen hazards that could occur.
This problem and alternative approaches are discussed in detail in the
paper Assessing the Safety and Nutritional Quality of Genetically
Engineered Foods (Attached).

The second factor contributing to the inadequacy of current regulations is
that these regulations are based on the principle of substantial
equivalence. Testing based on this principle focuses on potential risks
that can be anticipated on the basis of the known characteristics of the
food-producing organism that has undergone genetic modification or on the
basis of the known characteristics of the genes introduced into that
organism. However, testing based on this principle ignores the unexpected
hazards that are an unavoidable risk when an organism has been altered
using the process of genetic engineering.

In a testing program based on the principle of substantial equivalence,
selected characteristics of the genetically engineered food are compared to
those of its non-genetically engineered counterpart. If those selected
characteristics are found to be "substantially equivalent" in the
genetically engineered food and its non-genetically engineered counterpart,
it is concluded that, since the non-genetically engineered food has been
shown to be safe through long use, the genetically engineered food must be
equally safe.

This approach is based on the tacit assumption that measurements showing
that two foods are substantially equivalent with respect to certain
selected characteristics imply that those two foods are substantially
equivalent in all other characteristics relevant to the health and safety
of the consumer. This assumption is clearly not valid, especially in light
of the fact that the process of genetic engineering is inherently capable
of introducing unexpected changes in the characteristics of a food.

This approach is advantageous to industry because it speeds up the process
of commercialization by allowing developers to obtain certification that a
given genetically engineered food is safe without ever having to directly
measure characteristics, such as allergenicity, that are critical to
safety. However, this approach leaves consumers highly vulnerable to
undisclosed health risks of genetically engineered foods. This problem is
discussed in greater detail in the attached paper, The Failings of the
Principle of Substantial Equivalence in Regulating Transgenic Foods, in
which alternative approaches to testing are presented that can rectify this

Labeling and Segregation of Genetically Engineered Maize The US government
and the US biotechnology industry are pressing forcefully to import Bt
maize in a manner that obscures the fact that it is genetically engineered.
In so doing they are failing to respect the right of consumers to choose
for themselves whether or not to purchase and eat genetically engineered
foods. They have claimed that labeling of this maize as genetically
engineered is not feasible, because (a) it is impossible to distinguish it
from non-genetically engineered maize and (b) it has been mixed with
non-genetically engineered maize in US grain storage facilities. Both of
these claims are erroneous.

Testing-A highly sensitive and rigorous test is available that can
scientifically distinguish between genetically engineered and
non-genetically engineered maize. This test is available in the US through
Genetic ID, a US-based testing service, and in Europe through TNO Nutrition
and Food Institute in collaboration with Genetic ID. TNO is an applied
research organization established through an act of the parliament of the
Netherlands. This test is capable of positively detecting genetically
engineered maize even if it is present at only one kernel in 10,000.

Segregation-Although regulations in the US do not require genetically
engineered maize to be segregated from non-genetically engineered
varieties, in practice the vast majority of genetically engineered maize
has been segregated informally by farmers and grain dealers. This has been
done because they have been very much aware of the controversy in Europe
regarding this maize. In actuality, Mycogen has promised to buy back any
genetically engineered NatureGard maize (another Bt corn variety) that
farmers are unable to sell on the open market, and Ciba-Geigy has already
purchased a substantial portion of the harvest of their Bt corn to sell as
seed for the next growing season. Segregation must already be taking place
for these things to occur.

In light of the fact that less than 0.5% of the US maize harvest has been
genetically engineered, and the fact that even many of the large grain
dealers have been quietly segregating maize, the biotechnology industry's
claims that it is impossible to obtain sufficient non-genetically
engineered maize to meet Europe's needs are ridiculous, especially in light
of the fact that Europe normally purchases less than 5% of the US maize

Ecological and Agricultural Damage Rapid generation of Bt toxin-resistant
pests will be the primary ecological impact of the wide-spread
commercialization of maize varieties that have been genetically engineered
to produce Bt toxin endogenously.

Lepidopteran pests, such as the European maize borer are killed when they
consume Bt toxin produced endogenously in the tissues of maize plants
genetically engineered to carry the gene for Bt toxin. However, in any
insect population there will be a few individuals with natural resistance
to this toxin. These will survive to reproduce, and if all maize borers
except those with resistance are killed by consumption of Bt toxin, then
with each generation a growing portion of the maize borer population will
be resistant to this toxin. Over even a few growing seasons, such selective
pressure is likely to generate pest varieties that are highly resistant to
Bt toxin.

At present there is no scientifically proven strategy for preventing the
emergence of resistant insects. Industry has proposed a voluntary program
for using "refugia" to prevent or slow the development of Bt-resistant
insects. The refugia concept is a simple one: if in a given area some maize
is available that does not carry the Bt toxin (these plots are called
refugia), maize borers that are not resistant to Bt toxin will survive to
reproduce, thereby diluting out the selective effect of Bt toxin on the
next generation of maize borers.

The refugia concept is certainly a promising one. However, no research has
been done to demonstrate empirically whether or not refugia will be
effective. Instead of carrying out such research, the US government has
accepted industry's refugia plan without scientific evaluation. The
government has allowed Ciba-Geigy and Mycogen to market Bt maize seed to
farmers on a large scale, based on the promise that they will encourage
farmers to voluntarily create refugia along the perimeters of their fields.
This policy has been established in spite of strong objections from a large
number of highly respected ecologists, entomologists, and molecular

In practice, the refugia program has been sadly ineffective. As formulated,
the plan called for refugia representing from 15 to 25% of total maize
acreage. However, in practice farmers have been unwilling to "waste" such
large portions of their acreage in this way. Instead, much smaller refugia
have often been created, and in many cases, even these were mishandled. For
instance, many farmers completely negated the function of their refugia by
spraying them with chemical insecticides. This allowed them to harvest
marketable maize from their refugia, but spraying killed the Bt
toxin-sensitive insects that the refugia were designed to preserve. Clearly
a voluntary refugia program is not adequate to avoid the generation of Bt
toxin-resistant pests.

This approach has serious implications, not only for farmers who are
growing genetically engineered Bt maize, but also for organic, biological,
and ecological farmers. Organic farmers have been using Bt toxin as a
topical pesticide for many years. They spray their fields with a crude
extract from Bacillus thuringiensis to kill maize borers. Because the toxin
is rapidly destroyed by UV light, topically applied toxin is present in the
field for only a few days. This is a sufficient period of time to
substantially reduce the maize borer population, and control the pest, but
not long enough to select for Bt toxin-resistant variants. As a result,
resistant pests have not emerged, and Bt toxin has been used successfully
for many years, and is considered a highly valuable tool in the hands of
organic farmers.

The rapid generation of insects resistant to Bt toxin, due to the use of
genetically engineered Bt maize, will not only make genetically engineered
Bt maize varieties obsolete within a few growing seasons, but will also
deprive organic farmers of a valuable tool-topically applied Bt toxin-that
they have come to rely upon to protect their crops.

In summary, there is abundant scientific justification for barring
Ciba-Geigy's Bt maize from the European Community. We call for the European
Commission to take a strong position on this issue in which they exclude
this potentially harmful product from Europe. Such a position will protect
the health and safety of European citizens and will also protect the

Richard Wolfson,  PhD
Campaign to Ban Genetically Engineered Food
Natural Law Party
500 Wilbrod Street
Ottawa, ON  Canada  K1N 6N2
Tel. 613-565-8517  Fax. 613-565-6546
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Date:    Thu, 17 Apr 97 17:26:19 -0500 
From: (Richard Wolfson)To:      info@natural-law.caS
	  ubject: BT Corn issue

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