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December 17, 2000


Safe and Effective Food Biotechnology is in the Public



Martina McGloughlin
University of California, Davis

Washington Legal Foundation Critical Legal Issues Working Paper Series No.
99 November 2000
http://www.wlf.org Copyright 2000 Washington Legal Foundation

Agricultural food production is part of an increasingly complex global
agrifood system in which issues played out on one continent are instantly
felt around the world. Most scientists working in the field are in total
agreement with the stated mission of environmental and consumer groups
around the world; we need to feed and clothe the world's people while
minimizing the impact of agriculture on the environment.

But the human population continues to grow, while arable land is a finite
quantity (it is estimated that in the next 50 years it will be reduced by
half). So we must make optimum use of all tools to improve productivity
and quality of food production. As noted by Dr. Norman Borlaug, 1970 Nobel
Laureate and Father of the green revolution, "Biotechnology is a new
revolution providing feed, food and industrial products to support a
global population increasing at the rate of 1 00 million per year." Many
scientists believe biotech could raise overall crop productivity in
developing countries as much as 25% and help prevent the loss of those
crops after they are harvested. Without question the greatest impact of
biotech to date has been in medicine. Over 200 million people worldwide
have benefitted from the hundreds of diagnostics, therapeutics and
Copyright 2000 Washington Legal Foundation 2 vaccines produced by the
$25 billion biomedical biotechnology industry. But the greatest future
impact will be in plant agriculture. Unquestionably, this technology will
have a great impact on plant agriculture. (Abelson, P.A. and Hines, P.J.
1999, Serageldin, 1. 1999). The tools of biotechnology can be used to
improve texture, color, flavor, growing season, stress-tolerance, yield,
geographic distribution, disease resistance, shelf-life, and other
properties of production crops. Scientists can also enhance both the macro
and micro nutritional content of crop plants including amino acid ratio,
carbohydrate quality, vitamins, minerals and antioxidants.

In addition, the technology can be used to remove anti-nutrients such as
toxins and allergens. The ability to manipulate plant nutritional content
heralds an exciting new era and has the potential to directly benefit the
farmer, consumer and overall health of the nation and the world.
(DellaPenna, 1 999, Potrykus, 1 999). Scientists can use similar plant
delivery systems to provide not just enhanced nutrition but also vaccines
and therapeutics which are especially important in developing countries.
(Tacket, 1 998). In addition to plants, engineered microbes and enzymes
produced using recombinant DNA methods are used in many aspects of food
production. The cheese and bread we eat and the detergent we use to clean
our clothes all have been produced using engineered enzymes since the
early part of this decade Everyone is excruciatingly aware of the
devastating numbers of undernourished and even starving millions around
the world. The UN has put the number at about 800 million. Of course the
real issue is inequity in food distribution. Politics, culture and
regional conflicts all contribute to the problem Biotech will never be a
panacea for all the worlds ills, but it can go along way to addressing the
issues of inadequate nutrition. It is commonly known that rice is a staple
of a large proportion of the less developed countries (LDCs). Yet it is an
incomplete source of nutrients. Lack of two key nutrients, Vitamin A and
iron, result in over 400 million women and children suffering from such
ills as blindness, birth defects, anemia, poor development and increased
susceptibility to disease. By engineering the plant to produce
beta-carotene and iron and by removing anti nutrients that bind important
minerals such as iron this rice can help to alleviate these debilitating
deficiencies and maladies. This so-called "Golden Rice" will be made
available free through International Rice Research Institute (IRRI) thanks
to the Rockefeller Foundation and Zeneca.

In addition to improved nutrition there are many other benefits that
biotech can deliver to developing countries. The twin assaults of biotic
stress and abiotic stress are responsible for enormous crop losses in
developing countries - biotic stress being damage by viruses, fungi,
bacteria, nematodes and weeds, and abiotic stress in the form Copyright
2000 Washington Legal Foundation 3 of drought, cold, heat, and poor soils.
For example, parasitic weeds such as striga and orobanche are devastating
in many regions. In some areas, up to 90 percent of plants are killed by
parasites, and when seeds from these crops are harvested and resown the
problem is continuously propagated as the parasitic weed seeds adapt and
become difficult to separate from the crop seed. There are no existing
effective methods to control such parasitic weeds because herbicide
application will also kill the host plant. At UC Davis, researchers are
developing approaches to generate crops resistant to these parasites. In
Hawaii, the papaya industry was nearly wiped out by the papaya ring spot
virus for which there is no natural resistance. A single gene from the
virus itself acted like a vaccine to completely protect the plant and
restore the economy. A similar approach could be taken to address the
myriad viral disease in developing countries such as, for example,
cassava, a key source of protein in the African continent. Two years ago,
Africa lost more than half its cassava crop to the cassava mosaic virus.

By reducing dependency on chemicals and tillage through the development of
natural fertilizers and of pest-resistant plants, biotechnology has the
potential to conserve natural resources, prevent soil erosion, and improve
environmental quality. Pesticide use to control insect damage is also a
concern in developing countries. Nearly 40 percent of the world's food
crop is lost every year to pests, diseases and spoilage that biotech could
help prevent. The most cost-effective and environmentally sound general
method for controlling pests and disease is the use of that totally
organic substance DNA. This approach already has led to a reduction in the
use of sprayed chemical insecticides. A recent paper from the Economic
Research Service of the USDA reporting on same-year differences between
average pesticide use of adopters and nonadopters of the Bacillus
turingiensis (Bt) technologies revealed that adopters of engineered corn,
soybeans, and cotton combined used 7.6 million fewer acre-treatments of
pesticides than nonadopters in 1997. (An acre- treatment is the number of
acres treated multiplied by the number of pesticide treatments.) The
difference rose to nearly 1 7 million fewer acre-treatments by adopters in
1 998. An additional advantage is that through Bt protection, mycotoxin
contamination was down by 92 percent. (USDA/ERS July, 1999, August, 2000;
Gianessi, 1999). These deadly toxins produced by fungi have been found,
among other things, to cause brain tumors in horses and liver cancer in
children. The U.S. National Center for Food and Agricultural Policy study
found Roundup Ready soybeans offered several advantages to farmers,
including easier weed management, less injury to crops, no restrictions on
crop rotations, a decrease tillage, Copyright 2000 Washington Legal
Foundation 4 and cheaper costs. U.S. farmers using Roundup Ready soybeans
saved an estimated $220 million in 1998 due to lower herbicide costs. The
broad spectrum of weeds controlled by glyphosate means that soybean
growers no longer need to make as many multiple applications with
combinations of herbicides. (Gianessi, 2000).

Adoption rates for transgenic crops are some of the highest for new
technologies by agricultural industry standards. High adoption rates
reflect grower satisfaction with the products that offer significant
benefits ranging from more flexible crop management, labor savings, higher
productivity, and a safer environment through decreased use of
conventional pesticides and shifts to reduced tillage systems which
collectively contribute to a more sustainable agriculture. Over half of
all economic benefits generated by these technologies have gone to
farmers, more than what has been appropriated by biotechnology and seed
companies combined.

Environmental stresses such as drought, heat, cold and non-optimal soils
can also be addressed. For example plants can be engineered with a gene
that preserves osmotic integrity and can protect plants from reduced water
availability and extremes of heat and cold. Similarly, a gene that
produces citric acid in roots can protect plants from soils contaminated
with aluminum. Genes such as these can allow crops to be cultivated in
hostile regions and temperatures increasing geographic range while
reducing potential impact on fragile ecosystems. Yield is an important
consideration in LDCS. By engineering metabolic pathways, for example for
nitrogen assimilation, sucrose hydrolysis, starch biosynthesis, and oxygen
assimilation, one can increase biomass production, especially protein and
starch in grains and tubers. In addition synthetic fertilizers, which are
typically unavailable to resource-poor farmers in less developed
countries, can be replaced with natural alternatives. For example, early
results at transforming rice with the nodulin gene indicate that this
staple can be colonized by bacteria that fix nitrogen from the atmosphere.
This would improve productivity in the absence of synthetic fertilizers.
(LDCS) (Dowling, 1998).

Of course making these technologies available to developing countries is
also an issue. Centers such as IRRI, International Service for the
Acquisition of Agri-biotech Applications (ISAAA), Center for the
Application of Molecular Biology to International Agriculture (CAMBIA),
international Laboratory for Tropical Biotechnology (ILTAB), and
Agricultural Biotechnology for Sustainable Productivity in Michigan all
are working with international agencies, biotech companies and local
communities to make relevant technologies available to farmers in
developing countries. In addition an increasing amount of biotech research
is being carried out in the developing countries themselves.

Scientific, civic, and religious opinion leaders from all over the world
have expressed support for the value of this technology. Florence Wambugu
of Kenya states that the great potential of biotechnology to increase
agriculture in Africa lies in its 'packaged technology in the seed,' which
ensures technology benefits without changing local cultural practices. She
observes that in the past, many foreign donors funded high-input projects,
which have not been sustainable because they have failed to address social
and economic issues such as changes in cultural practice.

Wambugu's position has been supported by two very August groups. Rev. Bob
Baker of the Church of England notes that, 'Genetic modification uses
nature's own God-given techniques for improving crops. For me, as a
Christian, there is an overriding reason for continuing with the trials.
Every year, millions of people die because carefully nurtured crops have
been wiped out by disease, drought or pests. Crops that can better resist
these enemies have the potential to transform the lives of whole
countries. We are called to love our neighbors and we owe it to them to
explore this way of helping them."

According to Bishop Elio Sgreccia, Vice President of the PontificalAcademy
for Life, "We are increasingly encouraged that the advantages of genetic
engineering of plants and animals are greater than the risks. The risks
should be carefully followed through openness, analysis and controls, but
without a sense of alarm....... We cannot agree with the position of some
groups that say it is against the will of God to meddle with the genetic
make-up of plants and animals."

The most trusted source of information in the U.S., the American Medical
Association (AMA), states that, "it is the policy of the AMA to endorse or
implement programs that will convince the public and government officials
that genetic manipulation is not inherently hazardous and that the health
and economic benefits of recombinant DNA technology greatly exceed any
risk posed to society.' The view that the present day recombinant
DNA-engineered organisms pose new or greater dangers to the environment or
human health are neither supported by the weight of scientific research
nor by a great majority of the scientific community. (Avery, 1999).
Biotechnology crops and foods have been carefully and extensively tested
over the past 1 5 years both in the laboratory and in controlled natural
environments under the oversight of the National Institutes of Health, the
EPA, the FDA, and the Animal & Plant Health Inspection Service / United
States Department of Agriculture (APHIS-USDA) (Regulatory Oversight
Webpage). Over 6,500 field tests have been analyzed by USDA involving more
than 18,000 sites throughout the United States. The agency has assessed
the biotech plants for their efficacy, performance, and suitability for
release in the environment. Additionally, around the world, some 25,000
field trials have been done on more than 60 crops in 45 countries,
including most of the 1 5 countries of the EU (international Field Test
Sources, 2000). There has not been a single report of any unexpected or
unusual outcome.

On April 5, 2000, the U.S. National Academy of Sciences issued a report,
which stated that there is no evidence suggesting foods produced through
biotechnology are any less safe than conventional crops. In fact, the
scientific panel concluded, growing such crops could have environmental,
advantages over other crops. Another recent report from a U.S. Congress
Committee on Science, which summarized the testimony of leading
scientists, made a very strong case for the safety of biotechnology and
warns against needless over- regulation, which could delay development of
a technology with great potential for public good. The subtly-altered
products on our plates have been put through more thorough testing than
any conventional food ever has been subjected to. Many 1 scientists who
worked in the past on crop improvement using much less precise methods of
cross breeding, or mutation-induced breeding, or wide species crosses
where hundreds of thousands of untested genes are combined did not undergo
the same type of scrutiny or inquiry. Ironically, many of our daily
staples would be banned if subjected to today's rigorous standards.
Potatoes and tomatoes contain toxic glycoalkaloids, which have been linked
to spina bifida. Kidney beans contain phytohaemagglutinin and are
poisonous if under cooked. And dozens of people die each year from
cynaogenic glycosides from peach seeds. Nevertheless, scientists working
on GMOs have used strict scientific principles and thorough analyses to
confirm for themselves and the public that the genes and techniques used
are safe for the consumer and for the environment.

The U.S. Food and Drug Administration (FDA) policy on foods from
genetically modified plants is built on scientific consensus. It addresses
the important food safety hazards allergens, toxins, nutrients, and
substances new to the food. The agency has evaluated technical evidence on
all proteins produced through biotechnology and which are currently in
commercial food products. As expected, all of these introduced proteins
are non-toxic, sensitive to heat, acid and enzymatic digestion and hence
rapidly digestible, and have no structural similarities with proteins
known to cause allergies. (Thompson, 2000). Based on the broad scientific
consensus on risks associated with biotech methods and products, FDA has
judged that the usual safety and quality control practices effectively
used over many decades by plant breeders are generally adequate for
ensuring food safety.

Extensive studies compare the improved plant with a conventionally bred
counterpart. Levels of protein, fat, fiber, starch, amino acids, fatty
acids, ash, and sugar are all compared with levels in the conventional
plant. Levels of anti- nutrients, natural toxicants or known allergens
likewise are compared. Field studies compare many biological parameters,
including height, color, leaf orientation, roots, flowering, shape,
strength, and grain size. Additional tests are performed when suggested by
the product's history of use, composition, or characteristics. If
inserting a new gene causes no change in all of the parameters examined,
the Food and Drug Administration can conclude with great assurance that
the improved crop is substantially equivalent to and as safe as the
conventional crop. (FDA, 1997, OECD, 1993, FAO/WHO, 1991). VI.

Much attention has been devoted to the recall of taco shells and other
food products that may contain StarLink corn. The Bt protein in StarLink,
Cry9C, does not resemble any known allergens and was not derived from an
allergenic source, nevertheless the protein is slightly more stable in
some digestion tests (one attribute of allergenic proteins) so it needs
more research before receiving approval for human consumption.
Allergenicity experts Copyright 2000 Washington Legal Foundation 8 say
that a high level of exposure to a protein is needed over a considerable
period of time for an individual to be sensitized. The amount of Cry9C in
corn kernels was less than 0.3% with considerably less than that in the
shells themselves as it was only a small component of all the corn and
other ingredients used. In addition, as this corn is processed at high
temperatures, the protein is denatured, and therefore no longer in a form
that could cause an allergic response. In effect there was little cause
for concern and the various companies quick action in recalling the
product and Aventis decision to stop all sales of the seeds, eliminated
any possibility of harm.

From an environmental perspective, an issue often raised is the question
of gene flow. Gene flow is the exchange of genetic information between
crops and wild relatives. The movement of genes via pollen dispersal
provides, in principle, a mechanism for foreign genes to "escape" from a
genetically modified crop and spread to weedy relatives growing nearby.
Gene flow becomes an environmental issue when the associated trait confers
some kind of ecological advantage. The risk of gene flow is not specific
to biotechnology. It applies equally well to herbicide resistant plants
that have been developed through traditional breeding techniques (e.g.,
STS soybeans). Moreover, gene flow is a constant concern of plant breeders
who worry about unwanted genes flowing into their f ields. In any case,
the "superweed" risk concept advanced for biotech herbicide-tolerant crops
is grossly exaggerated and fails to take into account strategies already
applied in agriculture. Resistance to a particular herbicide, if and when
developed, is managed with effectual alternative chemistries for most
economically relevant weeds. The question is not whether gene flow will
occur with crops that have been genetically modified (by natural,
conventional or biotech methods), but rather under what conditions could
it pose a serious problem and what alternative strategies are available to
address the potential risk. It is important to remember that for any gene
(nuclear or plastomic) to spread, there must be successful hybrid
formation between a sexually compatible crop plant and recipient species.
The two species must flower at the same time, share the same insect
pollinator (if insect-pollinated), and be close enough in space to allow
for the transfer of viable pollen. Thus, the transfer of transgenes will
depend on the sexual fertility of the hybrid progeny, their vigor and
sexual fertility in subsequent generations, and the selection pressure on
the host of the resident transgene. There are biotech-based strategies to
reduce the risk of gene flow. One possibility is the use of male sterile
plants, which works well but is limited to a few species. For the many
crops in which chloroplasts are strictly maternally inherited (i.e., not
transmitted through pollen), transformation of the chloroplast genome
should provide an effective way to contain foreign genes. (Daniel et al.,
1 998).

What about the monarch butterfly controversy? (Richards, 2000). If the
improved plant performs a function formerly performed by a chemical
pesticide, such as insect-protected corn or cotton, the Environmental
Protection Agency requires extensive studies to assess the safety to
humans as well as non-target insects and other wildlife. (EPA, 1997). The
inserted genetic material is tested on a range of non-target insect
species such as honeybees, green lacewings, ladybird beetles and
earthworms. It is also fed to birds, fish and mammals. In addition, USDA
monitors all biotech crops in several years' worth of field trials to see
if actual plantings have any adverse effect on wildlife. Activists have
alleged that regulators were surprised that insect-protected corn pollen
had an adverse effect on Monarch butterflies. (Losey, 1999, Hansen, 2000).
In truth, EPA considered the fact that the corn, which is harmless to
other wildlife, is intended to kill the larvae of lepidopteran insects
(moths and butterflies). Before granting approval for the corn, EPA
evaluated whether or not the larvae of desirable species, which do not
feed on corn, would be exposed. The agency evaluated the potential risk
and concluded that the benefit of removing chemical insecticide from the
environment outweighed the possibility that some butterflies might be
exposed. (Environmental Protection Agency Petition). After all the uproar,
caused by two laboratory studies in which Monarch larvae were forced to
eat the pollen, it is now clear that butterfly larvae have very little
exposure in the field. Over 20 recent field studies have borne out what
EPA projected more than four years ago. (Monarch Butterfly Symposium,
1999; Sears, 2000; Wraight, 2000).

The most that we can ask is that all foods produced by whatever method
receive the same level of evaluation both with regard to impact on the
environment, and safety to the consumer. Millions of people have already
eaten the products of genetic engineering and no adverse effects have been
demonstrated. Scientists are confident in the scientific validity of the
systems that regulate and oversee the American food supply. They are
equally confident that if we abandon the scientific process in judging the
safety of the food supply, we will slow or destroy the advances that will
reduce the use of unsafe chemicals and agricultural practices in this
country, and we will limit the wonderful potential of improved nutrition
and quality that promise to strengthen the agriculture economies in the
U.S.A. and around the world. As noted by former U.S. President Jimmy
Carter: 'Responsible biotechnology is not the enemy; starvation is.
Without adequate food supplies at affordable prices, we cannot expect
world health, or peace."

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