Genetic engineering is the process by which genes are altered and
transferred artificially from one organism to another. Genes,
which are made of DNA, contain the instructions according to
which cells produce proteins; proteins in turn form the basis for
most of a cell's functions. Genetic engineering makes it possible
to mix genetic material between organisms that could never breed
with each other. It allows people to take genes from one species,
such as a flounder, and insert them into another species, such as
a tomato -- thus, for example, creating a tomato that has some of
the characteristics of a fish.
Starting in the 1980s and accelerating rapidly in the past
decade, companies have begun using genetic engineering to insert
foreign genes into many crops, including important foods such as
corn and soybeans. Just in the past few years, genetically
engineered ingredients have begun appearing in many foods in U.S.
supermarkets; they have been detected in processed foods such as
infant formulas, drink mixes, and taco shells, to name a few
examples. These foods are not labeled, so consumers have no
way to know when they are eating genetically engineered food.
Genetic engineering is an extremely powerful technology whose
mechanisms are not fully understood even by those who do the
basic scientific work. In this series, we will review the main
problems that have been identified with genetically engineered
Most genetically engineered crops planted worldwide are designed
either to survive exposure to certain herbicides or to kill
certain insects. Herbicide tolerant crops accounted for 71% of
the acreage planted with genetically engineered crops in 1998 and
1999, and crops designed to kill insects (or designed both to
kill insects AND to withstand herbicides) accounted for most of
the remaining acreage. A small proportion (under 1%) of
genetically engineered crops planted in 1998 and 1999 were
designed to resist infection by certain viruses.
Genetically engineered herbicide-tolerant crops are able to
survive applications of herbicides that would ordinarily kill
them. The U.S. food supply currently includes products made from
genetically engineered herbicide-tolerant crops including
"Roundup Ready" canola, corn, and soybeans which are engineered
to withstand applications of Monsanto's Roundup (active
ingredient, glyphosate), as well as crops engineered to survive
exposure to other herbicides.
Genetically engineered pest-resistant (or pesticidal) crops are
toxic to insects that eat them. For example, corn can be
engineered to kill the European corn borer, an insect in the
order lepidoptera (the category that includes butterflies and
moths). This is accomplished by adding genetic material derived
from a soil bacterium, BACILLUS THURINGIENSIS (Bt), to the
genetic code of the corn. BACILLUS THURINGIENSIS naturally
produces a protein toxic to some insects, and organic farmers
sometimes spray Bt on their crops as a natural pesticide. In
genetically engineered "Bt corn," every cell of the corn plant
produces the toxin ordinarily found only in the bacterium.
Unfortunately, genetically engineered crops can have adverse
effects on human health and on ecosystems. And by failing to test
or regulate genetically engineered crops adequately, the U.S.
government has allowed corporations to introduce unfamiliar
substances into our food supply without any systematic safety
Here are some of the reasons why we might not want to eat
genetically engineered crops:
** Ordinary, familiar foods can become allergenic through the
addition of foreign genes.
Genetic engineering can introduce a known or unknown allergen
into a food that previously did not contain it. For example, a
soybean engineered to contain genes from a brazil nut was found
to produce allergic reactions in blood serum of individuals with
nut allergies. (See REHN #638.) Allergic reactions to nuts can be
serious and even fatal. Researchers were able to identify the
danger in this particular case because nut allergies are common
and it was possible to conduct proper tests on blood serum from
allergic individuals. In other cases, testing for allergenic
potential can be much more difficult. When genetic engineering
causes a familiar food to start producing a substance previously
not present in the human food supply, it is impossible to know
who may have an allergic reaction.
** Genetic engineering has the potential to make ordinary,
familiar foods become toxic.
In some cases, new characteristics introduced intentionally may
create toxicity. The Bt toxin as it appears in the bacteria that
produce it naturally is considered relatively safe for humans. In
these bacteria, the toxin exists in a "protoxin" form, which
becomes dangerous to insects only after it has been shortened, or
"activated," in the insect's digestive system. In contrast, some
genetically engineered Bt crops produce the toxin in its
activated form, which previously only appeared inside the
digestive systems of certain insects. Humans have little
experience with exposure to this form of the toxin. Furthermore,
in the past humans have had no opportunity or reason to ingest
any form of the Bt toxin in large quantities. When the Bt toxin
is incorporated into our common foods, we are exposed each time
we eat those foods.[6, pgs. 64-65.] And of course, a pesticide
engineered into every cell of a food source cannot simply be
washed off before a meal.
Toxicity can also result from characteristics introduced
unintentionally. For example, a plant that ordinarily produces
high amounts of a toxin in its leaves and low amounts in its
fruit could unexpectedly begin to concentrate the toxin in its
fruit after addition of a new gene. (See REHN #696.)
Unpleasant surprises of this sort can result from our ignorance
about exactly how a foreign gene has been incorporated into the
engineered cell. Foreign genes can be added to cells by various
methods; among other options, they can be blasted into cells
using a "gene gun," or a virus or bacterium can be used to carry
them into the target cells. The "genetic engineer" who sets
this process in motion does not actually control where the new
genes end up in the genetic code of the target organism. The
"engineer" essentially inserts the genes at a random, unknown
location in the cell's existing DNA. These newly-inserted genes
may sometimes end up in the middle of existing genetic
instructions, and may disrupt those instructions.
A foreign gene could, for example, be inserted in the middle of
an existing gene that instructs a plant to shut off production of
a toxin in its fruit. The foreign gene could disrupt the
functioning of this existing gene, causing the plant to produce
abnormal levels of the toxin in its fruit. This phenomenon is
known as "insertional mutagenesis" -- unpredictable changes
resulting from the position in which a new gene is inserted.
Genetic engineering can also introduce unexpected new toxicity in
food through a well-known phenomenon known as pleiotropy, in
which one gene affects multiple characteristics of an organism.
(See REHN #685.)
** Genetically engineered crops can indirectly promote the
development of antibiotic resistance, making it difficult or
impossible to treat common human diseases.
Whatever method is used to introduce foreign genes into a target
cell, it only works some of the time, so the "genetic engineer"
needs a way to identify those cells that have successfully taken
up the foreign genes. One way to identify these cells is to
attach a gene for antibiotic resistance to the gene intended for
insertion. After attempting to introduce the foreign genes, the
"engineer" can treat the mass of cells with an antibiotic. Only
those cells that have incorporated the new genes survive, because
they are now resistant to antibiotics.
>From these surviving cells, a new plant is generated. Each cell
of this plant contains the newly introduced genes, including the
gene for antibiotic resistance. Once in the food chain, in some
cases these genes could be taken up by and incorporated into the
genetic material of bacteria living in human or animal digestive
systems. A 1999 study published in APPLIED AND ENVIRONMENTAL
MICROBIOLOGY found evidence supporting the view that bacteria in
the human mouth could potentially take up antibiotic resistance
genes released from food. Antibiotic resistance among
disease-causing bacteria is already a major threat to public
health; due to the excessive use of antibiotics in medical
treatment and in agriculture, we are losing the ability to treat
life-threatening diseases such as pneumonia, tuberculosis, and
salmonella. (See REHN #402.) By putting antibiotic resistance
genes into our food, we may be increasing the public health
problem even further.
The British Medical Association, the leading association of
doctors in Britain, urged an end to the use of antibiotic
resistance genes in genetically engineered crops in a 1999
report. "There should be a ban on the use of antibiotic
resistance marker genes in GM [genetically modified] food, as the
risk to human health from antibiotic resistance developing in
micro-organisms is one of the major public health threats that
will be faced in the 21st Century. The risk that antibiotic
resistance may be passed on to bacteria affecting human beings,
through marker genes in the food chain, is one that cannot at
present be ruled out," the Association said.
To be continued.
*Rachel Massey is a consultant to Environmental Research
 Union of Concerned Scientists, "Foods on the Market,"
available at http://www.ucsusa.org. Choose "biotechnology" in the
bar at the bottom of the screen, then click on "Foods on the
 Consumers Union, "CONSUMER REPORTS: Genetically Engineered
Foods in Your Shopping Cart," Press Release, August 23, 1999.
Available at http://www.consumersunion.org/food/gefny999.htm.
 For one recent overview, see Environmental Media Services
(EMS), REPORTERS' GUIDE: GENETIC ENGINEERING IN AGRICULTURE,
Edition 1 (October 2000), available from EMS, Washington, D.C.,
(202) 463-6670 or at http://www.ems.org. Also see Pesticide
Action Network North America (PANNA), "Genetically Engineered
Crops and Foods: Online Presentation," available at
 Clive James, "Global Review of Commercialized Transgenic
Crops: 1999" ISAAA BRIEFS No. 12: Preview, produced by
International Service for the Acquisition of Agri-Biotech
Applications (ISAAA). Available at
 See Michael Hansen, "Potential Environmental and Human Health
Problems Associated with Genetically Engineered Food."
Presentation delivered at CREA International Seminar on
Transgenic Products, Curitiba, Brazil, October 11, 1999.
Available from Consumer Policy Institute, Yonkers, N.Y.:
 National Research Council, GENETICALLY MODIFIED
PEST-PROTECTED PLANTS: SCIENCE AND REGULATION (Washington, D.C.:
National Academy of Sciences, 2000). ISBN 0309069300.
 Union of Concerned Scientists, "Fact Sheet: Genetic
Engineering Techniques." Available at http://www.ucsusa.org.
Choose "biotechnology" in the bar at the bottom of the screen,
then click on "Genetic Engineering Techniques."
 See Food and Drug Administration, "Premarket Notice
Concerning Bioengineered Foods," FEDERAL REGISTER Vol. 66, No. 12
(January 18, 2001), pg. 4710.
 Derry K. Mercer and others, "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 (January 1999), pgs. 6-10.
 See World Health Organization (WHO), OVERCOMING
ANTIMICROBIAL RESISTANCE (Geneva, Switzerland: World Health
Organization, 2000). Available at
 British Medical Association Board of Science and Education,
"The Impact of Genetic Modification on Agriculture, Food and
Health -- An Interim Statement," May 1999. Summary statement
available at http://www.bma.org.uk/public/science/genmod.htm.
& HEALTH NEWS #717
---February 1, 2001--- .
BIOTECH--THE BASICS, PART 2
by Rachel Massey*
In the last issue, we looked at hazards associated with eating
genetically engineered foods: unexpected allergic reactions;
unexpected toxicity; and the development of antibiotic
resistance. It is increasingly clear that genetic engineering
is neither precise nor predictable; "genetic engineers" are
tampering with the instructions for basic cell functions, without
understanding fully how those instructions work.
** One source of unpredictable effects is the use of "promoter"
genes. As we saw in REHN #716, the aim of genetic engineering is
to take a gene from one organism and insert it into another
organism. However, organisms have elaborate defense mechanisms to
prevent foreign genes from affecting them, so a gene moved from a
bacterium to a plant will not automatically work in its new host.
To overcome the target organism's defenses and make the new gene
function, it is necessary to add a "promoter" gene -- a genetic
switch that "turns on" the foreign gene.
The promoter of choice in most cases is derived from a plant
virus called the cauliflower mosaic virus. Known as the CaMV 35S
promoter, this genetic sequence causes hyperexpression of other
genes. A gene is hyperexpressed when the proteins for which it
contains instructions are produced in excessive amounts --
perhaps ten to a thousand times as great as normal levels.
Because the CaMV 35S gene is so powerful, in addition to "turning
on" the target gene, it may also "turn on" other genes near where
it is inserted, causing the engineered cell to display
unpredictable new features.
** Plants can defend themselves against the intrusion of foreign
genetic instructions through the phenomenon of "gene silencing,"
in which the cell blocks expression of the foreign DNA. Silencing
may occur in unpredictable ways in genetically engineered plants.
For example, a recent study found that infection with the
cauliflower mosaic virus could trigger silencing of a newly
inserted trait for herbicide tolerance, which was linked to the
CaMV 35S promoter. Apparently, the plant defended itself against
the infection through silencing of the viral genes. At the same
time, it silenced other newly-inserted genes.
** Genetically engineered foods may also produce unexplained
health effects in laboratory animals. An article published in THE
LANCET by Stanley Ewen and Arpad Pusztai reports on a study of
laboratory rats fed genetically engineered potatoes. The
potatoes were designed to produce a substance known as GALANTHUS
NIVALIS agglutinin (GNA), which is ordinarily found in snowdrops
(a type of flower). The purpose of adding GNA to potatoes was to
increase resistance to certain insects and other pests.
Ewen and Pusztai worked with three groups of rats. One received
the genetically engineered potatoes designed to produce GNA; the
second received ordinary, non-engineered potatoes, without GNA;
and the third group received ordinary, non-engineered potatoes
mixed with a dose of GNA. Ewen and Pusztai studied the changes
that occurred in the digestive systems of the rats in each group.
The researchers found that eating engineered or non-engineered
potatoes with GNA was associated with certain changes in the
rats' stomachs. In addition, the engineered GNA potatoes were
associated with certain intestinal changes NOT found in the rats
fed ordinary potatoes laced with GNA. The researchers do not know
the reason for these additional changes. They could be due to a
"positioning effect" -- the foreign gene may have been inserted
at a location in the existing genetic material that caused it to
disrupt normal functioning of an existing gene. Or it could be
due to the activity of other genetic material inserted along with
the target gene, such as the promoter.
Pusztai was forced to retire from his research position at the
Rowett Research Institute in Scotland after he spoke publicly
about the results of his work. (See REHN #649.) His article in
THE LANCET is one of only a few animal feeding studies that have
been published on the altered foods that are now present,
unlabeled, in our grocery stores.
** In some cases, genetically engineered crops can have altered
nutritional content. One study found that glyphosate-tolerant
soybeans had significantly altered levels of naturally occurring
compounds known as isoflavones, which are thought to have some
health benefits. The consequences of changes like this could
be minor in some cases and serious in others. The important
lesson is that when we eat soy, corn, or other important foods
that have been genetically altered, we may not be getting the
nutrient mix we could expect in the past. As long as these
altered foods are unlabeled, we do not have the information we
need to make informed choices about the foods we eat.
Last fall, corn products in U.S. supermarkets were found to be
contaminated with "StarLink" corn, a genetically engineered
variety approved only for use as animal feed due to concerns
about possible allergic reactions in humans. The contamination
was detected by a non-governmental organization, Friends of the
Earth, working as part of a national collaborative effort, the
Genetically Engineered Food Alert coalition. Had Friends of the
Earth not taken responsibility for testing foods -- a function
that should be performed by government -- we could have continued
to consume unapproved StarLink corn with no way to trace the
health consequences. We do not know what other errors may already
have occurred; and since we do not know when we are eating
genetically engineered foods, we have no way to watch for links
between eating these foods and developing certain illnesses.
Those who favor the rapid and unregulated introduction of
genetically engineered foods into our food supply often say
genetic engineering is really nothing new; it is simply an
extension of conventional agricultural breeding techniques. In
fact, as Michael Hansen of Consumers Union explains in a review
article, there are some obvious differences.
** Gene transfers across natural boundaries: Conventional
breeding transfers genetic information among organisms that are
related to one another -- members of the same species, or related
species, or (rarely) of closely-related genera. (Genera is the
plural of genus; a genus is a biological grouping that includes
multiple species.) Genetic engineering, on the other hand, may
transfer genes from any organism to any other organism (fish to
fruit, bacteria to vegetables, etc.).
** Location of gene insertion: Variations of a gene are known as
alleles. Genes are carried in chromosomes, and each gene has a
specific place in a chromosome. Conventional breeding shuffles
alleles of existing genes. In general, conventional breeding does
not move genes from one place to another in a chromosome. Genetic
engineering, on the other hand, inserts genes that were not in
the original chromosome of the target organism. These genes may
be inserted in unpredictable locations in the chromosome,
producing unforseeable changes in the plant.
** Extra genetic material: Genetically engineered foods contain
extra genetic material that is unrelated to the target
characteristics. This extra genetic material can include vectors,
which are added to move genes across natural barriers; promoters,
added to "turn on" the foreign genes; marker genes, added to show
the engineer whether the target gene has been successfully
inserted; and random extra genetic material that the engineer
inserts unintentionally. Here is a brief discussion of each of
a) Vectors: Genetic engineering often uses "vectors," genetic
sequences derived from viruses or bacteria, to move genes into
the target cell. One vector used frequently is derived from
AGROBACTERIUM TUMEFACIENS, a bacterium that causes tumors in
plants by inserting DNA from its own genetic code into the
genetic code of the plant. A study published in PROCEEDINGS OF
THE NATIONAL ACADEMY OF SCIENCES in January 2001 reported that
AGROBACTERIUM may be able to insert DNA into human cells as
When AGROBACTERIUM infects a plant under natural conditions, the
genes are incorporated only into the infected part of the plant;
they do not move throughout the plant and are not passed on to
subsequent generations. In contrast, when AGROBACTERIUM genes are
used as vectors in genetic engineering, the resulting plant
includes AGROBACTERIUM genes in all its cells. Conventional
breeding does not require the use of vectors.
b) Promoters: As we have seen, most genetically engineered crops
include the CaMV 35S "promoter" gene to "turn on" the foreign
gene and overcome normal cell defense mechanisms. Viral promoters
are not necessary for conventional breeding.
c) Marker genes: As we saw in REHN #716, genetic engineering
often involves the insertion of antibiotic resistance marker
genes. This does not occur in conventional breeding.
d) Unintentional additions: Sometimes genetic engineers introduce
additional genetic material into the target cell without knowing
it. Last spring, for example, newspapers reported that Monsanto's
Roundup Ready (glyphosate-tolerant) soybeans contained extra
fragments of DNA that the company's genetic engineers were not
aware of having introduced.
On the basis of these points, some people would say that genetic
engineering is "very different" from conventional breeding,
whereas others would say that it is only "somewhat different."
Either way, the differences have obvious implications for the
ways in which governments should regulate genetically engineered
foods. At a minimum, governments should require companies to
conduct pre-market safety tests related to the special hazards
associated with genetic engineering, and any altered foods
allowed onto the market should be labeled.
[To be continued.]
*Rachel Massey is a consultant to Environmental Research
 For a thorough collection of resources on agricultural
biotechnology, see AgBioTech InfoNet, maintained by Benbrook
Consulting Services at http://www.biotech-info.net.
 Michael K. Hansen, "Genetic Engineering is Not an Extension
of Conventional Plant Breeding; How Genetic Engineering Differs
from Conventional Breeding, Hybridization, Wide Crosses, and
Horizontal Gene Transfer," available at http://-
www.consumersunion.org/food/widecpi200.htm. Also see Michael
Hansen and Ellen Hickey, "Genetic Engineering: Imprecise and
Unpredictable," in GLOBAL PESTICIDE CAMPAIGNER, Vol. 10, No. 1,
April 2000, available from Pesticide Action Network
 Nadia S. Al-Kaff and others, "Plants Rendered
Herbicide-Susceptible by Cauliflower Mosaic Virus-Elicited
Suppression of a 35S Promoter-Regulated Transgene," NATURE
BIOTECHNOLOGY Vol. 18 (September 2000), pgs. 995-999.
 Stanley W. B. Ewen and Arpad Pusztai, "Effect of Diets
Containing Genetically Modified Potatoes Expressing GALANTHUS
NIVALIS Lectin on Rat Small Intestine," THE LANCET Vol. 354, No.
9187 (October 16, 1999), pgs. 1353-1354.
 Marc A. Lappe and others, "Alterations in Clinically
Important Phytoestrogens in Genetically Modified,
Herbicide-Tolerant Soybeans," JOURNAL OF MEDICINAL FOOD Vol. 1,
No. 4 (July 1999), pgs. 241-245.
 Andrew Pollack, "Case Illustrates Risks of Altered Food." NEW
YORK TIMES October 14, 2000. Available at http://-
 Talya Kunik and others, "Genetic Transformation of HeLa Cells
by AGROBACTERIUM," PROCEEDINGS OF THE NATIONAL ACADEMY OF
SCIENCES, published online before print (January 30, 2001). Full
text available for U.S. $5 at
 James Meikle, "Soya Gene Find Fuels Doubts on GM Crops," THE
GUARDIAN (London) (May 31, 2000). Available at http://-
Also see "Monsanto GM Seeds Contain 'Rogue' DNA," SCOTLAND ON
SUNDAY (May 30, 2000). Available at http://www.biotech-info.net/-
ENVIRONMENT & HEALTH NEWS #718
---February 15, 2001--- .
BIOTECH: THE BASICS, PART 3
By Rachel Massey*
As we saw in REHN #716, genetically engineered crops now planted
in the U.S. and worldwide are mostly designed to tolerate
herbicides or to kill insects or other pests. A small percentage
is designed for other purposes such as resisting infection by
certain viruses. Here we will look at some of the threats
genetically engineered crops pose to ecosystems.
Pesticidal crops may be toxic to nontarget organisms - organisms
they were not designed to kill. For example, BT corn designed to
kill the European corn borer can also be toxic to other closely
related insects, including butterflies and moths.
Monarch butterfly larvae feed on milkweed, which often grows in
or near corn fields. In a laboratory, scientists found that
monarch larvae feeding on milkweed dusted with BT corn pollen
grew more slowly and died at a higher rate than larvae that were
not exposed to the toxic pollen. Another study found these
effects were likely to occur outside the laboratory as well.
Researchers placed potted milkweed plants in fields of BT corn
and measured the number of BT pollen grains that were deposited
on the milkweed leaves. Monarch larvae exposed to BT corn pollen
at these levels had high death rates compared with larvae exposed
to non-engineered corn pollen or placed on milkweed leaves with
The U.S. Environmental Protection Agency (EPA) now expresses
concern about the effects of BT corn pollen on monarchs and other
butterfly species, including the endangered Karner Blue
butterfly. EPA has asked companies to submit data on these
effects, but this "data call-in" occurred four years AFTER EPA
allowed BT corn to be used on U.S. farms.[2,pg.13]
BT corn may also harm the green lacewing, a beneficial insect
that eats agricultural pests. The lacewing may be affected by the
toxin in the digestive systems of insects that have eaten BT corn
but have not been killed by it. This example shows how
non-target effects may interfere with a chain of predator-prey
relationships, disrupting the natural balance that keeps pest
populations under control.
BT crops may also affect non-target organisms by changing soil
chemistry. A 1999 article in NATURE reported that the roots of BT
corn plants released BT toxin into soil. The researchers found
that 90 to 95% of susceptible insect larvae exposed to the
substance released from the roots died after 5 days.
The use of BT crops can also promote the development of
BT-resistant pest populations. As we saw in REHN #716, organic
farmers use BT sprays occasionally as a natural insecticide to
combat severe pest outbreaks. BT crops, in contrast, generally
expose insects to BT toxins day after day, whether or not there
is a major infestation. These conditions increase the likelihood
that BT-resistant insects will evolve. The widespread appearance
of BT-resistant insect pests would mean the loss of one of the
most valuable tools available to organic farmers for dealing with
serious pest outbreaks.[6,pg.139]
Herbicide-tolerant crops are designed to make it easier for
farmers to use certain herbicides. A 1999 study of soybean
farming in the U.S. midwest found that farmers planting Roundup
Ready soybeans used 2 to 5 times as many pounds of herbicide per
acre as farmers using conventional systems, and ten times as much
herbicide as farmers using Integrated Weed Management systems,
which are intended to reduce the need for chemical
herbicides.[7,pg.2] Glyphosate, the active ingredient in Roundup,
can sometimes persist in soil over long periods of time and
may affect the growth of beneficial soil bacteria, among other
environmental effects. A recent, unpublished study conducted
at the University of Missouri suggests that applications of
Roundup to Roundup Ready crops may be associated with elevated
levels of soil fungi that sometimes cause plant diseases.
More hazards may lie ahead as new products of genetic engineering
come to market. According to the NEW YORK TIMES, Scotts Company
is collaborating with Monsanto to develop Roundup Ready grass for
lawns. Studies suggest that Roundup exposures can be harmful
to human health. For example, exposure to glyphosate herbicides
may be associated with increased occurrence of non-Hodgkins
lymphoma, a cancer of white blood cells. (See REHN #660.) And
a study published last August in ENVIRONMENTAL HEALTH
PERSPECTIVES found that in a laboratory, Roundup exposure
interfered with sex hormone production in cells of testicular
tumors taken from mice. If the introduction of Roundup Ready
grass leads to increased use of Roundup on lawns, children's
exposure to the herbicide could rise.
In some cases, genetically engineered crops might become problem
weeds, disrupting existing ecosystems. A recent study published
in NATURE found that some genetically engineered crops are
unlikely to become problem weeds. Researchers planted genetically
engineered crops that were available in 1990 and monitored their
growth for ten years. Many of the plants simply died out, and
those that did survive showed no signs of spreading. But some
crop plants, such as canola, survive well on their own without
human intervention. In Canada, genetically engineered canola
plants designed to resist various herbicides appear to have
exchanged genetic material so that some canola plants now can
survive exposure to two or three herbicides. These plants with
multiple herbicide resistance can be difficult for farmers to
Genetically engineered virus-resistant crops are supposed to
reduce problems from viral infections, but in some cases they
could make those problems worse. Virus-resistant crops are
created by adding virus genes to the plant's existing genetic
material. If a genetically engineered crop resistant to one virus
is infected by another virus, the genetic material from the two
viruses may sometimes interact to produce new virus types, which
could be more harmful or could infect a wider range of plants
than the original.[15,pgs.59-68]
All the hazards discussed above are compounded by the problem of
genetic pollution. Many crop plants disperse genetic material
through pollen, which may be carried by the wind or by
pollinators such as bees. This means genetically engineered
plants may "share" their genetic material with other,
non-engineered plants. For example, pollen from genetically
engineered corn can blow into a neighboring field and pollinate
conventional corn. Because of genetic pollution, some organic
farmers whose fields border genetically engineered crops may no
longer be able to certify their crops as organic.[6,pg.127]
In animals, sexual reproduction between different species is
usually impossible. In a few cases, reproduction between closely
related species can occur but the offspring are generally
sterile. For example, a horse and a donkey can mate to produce a
mule, but mules cannot reproduce. In contrast, many plants are
able to reproduce sexually with related species, and the
offspring of these combinations are often fertile. When crop
plants grow near wild plants to which they are related, they may
reproduce with these plants. This means that genetic material
inserted into a crop plant can find its way into wild plant
A recent article in SCIENCE reviews the literature on "ecological
risks and benefits" of genetically engineered crops and confirms
what advocates of precaution have been saying for years: we lack
basic information on how genetically engineered crops may affect
ecosystems. Here are a few examples of what scientists do not
know about ecological effects of genetically engineered crops:
** No published studies have looked at whether novel genes
introduced into crops have become established in populations of
wild relatives.[16, pg. 2088]
** We know that BT toxin can be released from the roots of BT
corn plants, but no published studies have looked at the
ecological consequences of adding BT toxin to soil in this way.
[16, pg. 2089]
** As we have seen, BT toxin in the digestive systems of
plant-eating insects may affect the predator insects that eat
them. Right now it is impossible to model how an ecosystem might
change due to these effects on predators, the authors say.[16,
** Scientists are currently unable to estimate the likelihood
that planting genetically engineered virus-resistant crops will
lead to the development of new types of plant viruses. [16, pg.
A precautionary approach would require that we investigate these
questions before, rather than after, permitting large-scale
commercial cultivation of genetically engineered crops.
*Rachel Massey is a consultant to Environmental Research
 John E. Losey and others, "Transgenic Pollen Harms Monarch
Larvae." NATURE Vol. 399, No. 6733 (May 20, 1999), pg. 214.
 Laura C. Hansen and John J. Obrycki, "Field Deposition of BT
Transgenic Corn Pollen: Lethal Effects on the Monarch Butterfly,"
OECOLOGIA Vol. 125, No. 2 (2000), pgs. 241-248.
 U.S. Environmental Protection Agency, "Biopesticide Fact
Sheet: BACILLUS THURINGIENSIS Cry1Ab Delta-Endotoxin and the
Genetic Material Necessary for Its Production (Plasmid Vector
pCIB4431) in Corn [Event 176]," April 2000. EPA Publication No.
730-F-00-003. Available at
 A. Hilbeck and others, "Effects of Transgenic BACILLUS
THURINGIENSIS corn-fed prey on Mortality and Development Time of
Immature CHYSOPERLA CARNEA (Neuroptera: Chrysopidae)."
ENVIRONMENTAL ENTOMOLOGY Vol. 27, No. 2 (April 1998), pgs.
 Deepak Saxena and others, "Insecticidal Toxin in Root
Exudates from BT Corn," NATURE Vol. 402, No. 6761 (December 2,
1999), pg. 480.
 Royal Society of Canada, ELEMENTS OF PRECAUTION:
RECOMMENDATIONS FOR THE REGULATION OF FOOD BIOTECHNOLOGY IN
CANADA (Ottawa: Royal Society of Canada, January 2001). ISBN
0-920064-71-X. Available from the Royal Society at (Ottawa,
Canada) phone: (613) 991-6990 or at
 Charles Benbrook, "Evidence of the Magnitude and Consequences
of the Roundup Ready Soybean Yield Drag from University-Based
Varietal Trials in 1998," AgBioTech InfoNet Technical Paper #1,
July 13, 1999. Available at
 U.S. Environmental Protection Agency, "Pesticide and
Environmental Fate One Line Summary: Glyphosate," May 6, 1993.
 See T. B. Moorman and others, "Production of Hydrobenzoic
Acids by BRADYRHIZOBIUM JAPONICUM strains after treatment with
glyphosate." JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY Vol. 40
(1992), pgs. 289-293. For a review of other relevant studies, see
Caroline Cox, "Herbicide Factsheet: Glyphosate (Roundup)" JOURNAL
OF PESTICIDE REFORM Vol. 18, No. 3 (Fall 1998), updated October
2000, available at http://www.pesticide.org/gly.pdf
 R.J. Kremer and others, "Herbicide Impact on FUSARIUM spp.
and Soybean Cyst Nematode in Glyphosate-Tolerant Soybean."
American Society of Agronomy study abstract, available at
http://www.biotech-info.net/fungi_buildup_abstract.html. Also see
University of Missouri press release, "MU Researchers Find Fungi
Buildup in Glyphosate-Treated Soybean Fields" (December 21,
2000), available at
 David Barboza, "Suburban Genetics: Scientists Searching for
a Perfect Lawn," NEW YORK TIMES July 9, 2000, pg. A1.
 Lennart Hardell and Mikael Eriksson, "A Case-Control Study
of Non-Hodgkin Lymphoma and Exposure to Pesticides," CANCER Vol.
85, No. 6 (March 15, 1999), pgs. 1353-1360.
 Lance P. Walsh and others, "Roundup Inhibits Steroidogenesis
by Disrupting Steroidogenic Acute Regulatory (StAR) Protein
Expression," ENVIRONMENTAL HEALTH PERSPECTIVES Vol. 108, No. 8
(August 2000), pgs. 769-776.
 M. Crawley and others, "Transgenic Crops in Natural
Habitats." NATURE Vol. 409, No. 6821 (February 8, 2001), pgs.
 Jane Rissler and Margaret Mellon, THE ECOLOGICAL RISKS OF
ENGINEERED CROPS (Cambridge, Mass.: MIT Press, 1996).
 L. L. Wolfenbarger and P.R. Phifer, "The Ecological Risks
and Benefits of Genetically Engineered Plants." SCIENCE Vol. 290
No. 5499 (December 15, 2000) pgs. 2088-2093.
RACHEL'S ENVIRONMENT & HEALTH NEWS #719 .
---March 1, 2001--- .
BIOTECH--THE BASICS, FINAL PART
by Rachel Massey*
Biotechnology corporations want people in the U.S. and around the
world to believe that the U.S. government has fully tested
genetically engineered crops for ecological and human health
hazards. Three federal agencies -- U.S. Food and Drug
Administration (FDA), U.S. Department of Agriculture (USDA), and
U.S. Environmental Protection Agency (EPA) -- have responsibility
for genetically engineered foods, but there is no guarantee that
a genetically engineered food sold in the U.S. has been tested
for ecological or human health effects. In the rush to promote
genetic engineering, safety testing has fallen through the
Biotechnology corporations also want us to believe that
genetically engineered foods have been embraced by the public. In
fact, genetically engineered foods are not labeled, so the public
has no knowledge -- and no choice -- about purchasing and eating
U.S. Food and Drug Administration
The U.S. Food and Drug Administration (FDA) issued its basic
policy statement on genetically engineered foods in 1992. Under
this policy, FDA considers genetically engineered foods to be
"generally recognized as safe" (GRAS), unless in the judgment of
the manufacturer there is some reason for concern.[2, pg. 22990]
Foods considered GRAS are not subject to pre-market safety
FDA states that the need for safety testing depends on the
characteristics of a food, not on the methods used to produce it.
In other words, the fact that a food was produced using genetic
engineering is not sufficient to trigger safety tests.[2, pgs.
FDA's 1992 policy says that a genetically engineered food must be
labeled if it "differs from its traditional counterpart such that
the common or usual name no longer applies to the new food, or if
a safety or usage issue exists to which consumers must be
alerted."[2, pg. 22991] For example, it says a tomato containing
peanut genes might need to be labeled so that people with peanut
allergies could avoid it.[2, pg. 22991] But FDA allows
biotechnology corporations to decide whether a hazard of this
sort exists. Under FDA's no-labels policy, we can find out the
fat, cholesterol, sodium, potassium, carbohydrate, and protein
content of our breakfast cereal but we can't find out whether it
contains antibiotic-resistance genes, viral promoters, or
proteins normally produced only by bacteria. (See REHN #716,
In 1998 a coalition of non-governmental organizations,
scientists, and others filed a lawsuit against FDA for failing to
fulfill its regulatory duties. During the suit, FDA was forced to
release internal documents that showed FDA staff scientists had
strongly opposed the 1992 policy. (See REHN #685.)
The lawsuit also forced FDA to release details of its safety
evaluation of the first genetically engineered food that entered
U.S. supermarkets, the Flavr Savr tomato. Calgene, the company
that developed the Flavr Savr, submitted three safety tests to
FDA in which rats were fed engineered tomatoes. After
twenty-eight days of the Flavr Savr tomato diet, researchers
examined the rats' stomachs. The three studies produced
inconsistent results that Calgene was unable to explain. The
first study showed no unusual effects. In the second study, some
of the rats fed genetically engineered tomatoes developed gastric
erosions (damage to the lining of the stomach). In the third
study, gastric erosions appeared in some of the rats fed
genetically engineered tomatoes AND in some of the rats fed
Calgene concluded these stomach problems were unrelated to eating
genetically engineered tomatoes, but it had no explanation for
why they appeared. An FDA staff scientist who reviewed Calgene's
data said there were "doubts as to the validity of any scientific
conclusion(s) which may be drawn from the studies' findings,"
because Calgene could not explain the variations in results among
the three tests. In spite of the doubts expressed by its own
staff, FDA categorized the Flavr Savr tomato as GRAS and approved
it for sale. (The Flavr Savr did not sell well, so it has
disappeared from stores.)[1, pgs. 83-84]
In January 2001, the FDA proposed new regulations on genetically
engineered food. These proposed regulations still fail to require
either pre-market safety testing or labeling of genetically
engineered foods. FDA says "there does not appear to be any
new scientific information that raises questions about the safety
of bioengineered food currently being marketed," and states once
again that genetically engineered foods are "generally recognized
as safe."[6, pgs. 4708-9]
To make this claim, FDA had to ignore scientific information that
had been brought to its attention explicitly during the previous
year. In March 2000, the Center for Food Safety and partner
organizations filed a legal petition asking FDA to start
requiring pre-market safety testing, environmental impact
assessments, and labeling for all genetically engineered foods.
The petition included a thorough review of new scientific
evidence on safety concerns associated with genetic
The main new requirement in FDA's proposed regulations is that
producers of genetically engineered foods must notify FDA 120
days before bringing a new genetically engineered food to market.
This notification, known as a pre-market biotechnology notice
(PBN), would include various information, such as whether the
product contains antibiotic-resistance marker genes and whether
it is likely to produce allergic reactions. FDA says it will make
a list of PBNs available to the public, but the list may not be
complete. In some cases, FDA says, the existence of a PBN could
be considered "confidential commercial information."[6, pg.
4723] As a result, under the proposed regulations a company could
market a genetically engineered food without any public
notification. FDA's proposed regulations are open for public
comment until April 3, 2001.
FDA has also proposed to create non-binding guidance for
voluntary labeling. This guidance is clearly not intended for
companies using genetically engineered crops, which have nothing
to gain by telling consumers what is in their food. Instead, the
guidance undermines consumers' right to know what they are buying
and threatens to limit the free speech of organic and other food
producers, by discouraging the use of labels with phrases such as
"biotech free" or "no genetically engineered materials." FDA says
these labels will be misleading on most foods, because ordinary
food could be contaminated with the products of genetic
engineering. In addition, FDA says these phrases could imply that
non-engineered food is superior to engineered food, which, FDA
says, would be misleading.[8, pg. 4840]
U.S. Department of Agriculture
Under the Federal Plant Pest Act, the U.S. Department of
Agriculture (USDA) is responsible for regulating "plant pests" --
organisms that could cause harm to a plant. USDA considers
genetically engineered plants to be possible plant pests if they
contain genetic material from organisms, such as some bacteria,
included on an official list of plant pests.[1, pg. 109] Plants
engineered without the use of genes from a recognized plant pest
may escape USDA regulation entirely. Even when genes from a plant
pest are involved, the manufacturer has discretion to decide
whether the engineered plant is itself a plant pest. USDA does
not tell manufacturers what data to take into account when they
make this decision.[1, pgs. 110-111]
Under USDA's rules, genetically engineered crops that are
considered plant pests must first be approved for field testing
before they are approved for commercial planting. After
conducting field tests, the developer of a genetically engineered
crop can apply for "nonregulated status," under which the crop
can be planted commercially with no further oversight from USDA.
USDA leaves it up to the developer to decide what data to submit
in support of its application for nonregulated status.[1, pg.
111] According to a recent article in AMERICAN SCIENTIST, many
tests that companies submit to USDA are poorly designed, so they
are unlikely to reveal any adverse effects that may occur.
U.S. Environmental Protection Agency
As we saw in REHN #716, crops can be engineered to kill certain
insects by adding a gene derived from the bacterium BACILLUS
THURINGIENSIS (Bt). Under its authority to regulate pesticides,
the U.S. Environmental Protection Agency (EPA) is responsible for
evaluating the health and environmental consequences of these
engineered plants, which are, themselves, pesticidal.
EPA has registered pesticidal crops for five years, but the
agency makes these registration decisions on a case-by-case
basis; it does not have a standard testing system tailored to the
hazards posed by genetically engineered crops.[1, pg. 176] EPA
says it is reviewing existing registrations for Bt corn and
cotton this year, in order to decide whether it is safe to
continue growing them.
When EPA registers a chemical pesticide for use on food crops, it
establishes a tolerance level -- an amount of pesticide residue
that is allowable on food. However, thus far EPA has exempted all
pesticidal crops from this requirement.[1, pg. 106]
Pesticidal crops are likely to promote the development of Bt-
resistant pest populations. (See REHN #637, #718.) Despite ample
scientific knowledge about this danger, EPA waited until December
1999 to issue requirements for resistance management. Under these
requirements, companies selling Bt corn are responsible for
making sure that farmers grow "refuges" of ordinary corn
alongside their pesticidal crops. The idea is that some pest
insects will eat only the ordinary corn, so they will be
sheltered from the evolutionary pressure that promotes the
development of resistant pest populations.[1, pgs. 106-7]
In the past five years, corporations have introduced a powerful
new technology into our food system without understanding the
basics of how this technology works. Government agencies have
refused to gather crucial data on how this technology can affect
ecosystems and human health. Once again, we are flying blind.
*Rachel Massey is a consultant to Environmental Research
 Thomas O. McGarity and Patricia I. Hansen, BREEDING DISTRUST:
AN ASSESSMENT AND RECOMMENDATIONS FOR IMPROVING THE REGULATION OF
PLANT DERIVED GENETICALLY MODIFIED FOODS. Report prepared for the
Food Policy Institute of the Consumer Federation of America,
January 11, 2001. Available at http://-
 U.S Food and Drug Administration (FDA), "Statement of Policy:
Food Derived from New Plant Varieties," FEDERAL REGISTER Vol. 57,
No. 104, May 29, 1992, pgs. 22984-23005. Available at
 Marion Burros, "Documents Show Officials Disagreed on Altered
Food," NEW YORK TIMES December 1, 1999. Available at
 Fred A. Hines, "FLAVR SAVR Tomato (Pathology Review PR-152;
FDA Number FMF-000526): Pathology Branch's Evaluation of Rats
with Stomach Lesions from Three Four-Week Oral (Gavage) Toxicity
Studies (IRDC Study Nos. 677-002, 677-004, and 677-005) and an
Expert Panel's Report." Memo to Linda Kahl, Biotechnology Policy
Branch, June 16, 1993. Available at
 See Joseph Mendelson, "The Food and Drug Administration's New
Proposal on Genetically Engineered Foods: First Draft Analysis,"
January 17, 2001. Available at http://-
CFSNewFDAAnalysis.html?cam_id=70. Also see this web site for
information on writing to FDA about the proposed regulations.
 U.S. Food and Drug Administration (FDA), "Premarket Notice
Concerning Bioengineered Foods," FEDERAL REGISTER Vol. 66, No.
12, January 18, 2001, pgs. 4706-4738. Available at http://-
 Center for Food Safety and others, "Citizen Petition Before
the United States Food and Drug Administration." Available at
 U.S. Food and Drug Administration (FDA), "Draft Guidance for
Industry: Voluntary Labeling Indicating Whether Foods Have or
Have Not Been Developed Using Bioengineering; Availability,"
FEDERAL REGISTER Vol. 66, No. 12, January 18, 2001, pgs.
4839-4842. Available at http://www.centerforfoodsafety.org/-
 Michelle Marvier, "Ecology of Transgenic Crops," AMERICAN
SCIENTIST Vol. 89, No. 2 (March-April, 2001), pgs. 160-167.
Available at http://americanscientist.org/articles/01articles/-
 See Union of Concerned Scientists, "Bt Crop Renewals,"
Thanks to Charles Benbrook, Caroline Cox, Michael Hansen, Ellen
Hickey, Sheldon Krimsky, and Joseph Mendelson for reviewing
portions of this series.
In accordance with Title 17 U.S.C. Section 107 this material is
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