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Engineered Food Issues
Allergic reactions and other possible
health risks
Threats to the environment
Allergic
reactions and other possible health risks
By now, millions of acres of genetically engineered crops
have been planted, and nearly two-thirds of the products on
our supermarket shelves contain GE ingredients. But GE foods
remain poorly studied; scientists simply can't say with any
authority that they are absolutely safe for human consumption.
In fact, many questions persist.
Essentially, we've been subjected to a
massive experiment on human health. What will the results
of this experiment be? Stay tuned.
Genetic engineering is a young, and in many ways poorly
understood, technology. Many scientists believe that genetically
engineered foods have been rushed much too quickly to market--to
boost multinationals' profit margins--before adequate testing
has been completed to ensure public health.
Early in 2001, the Royal Society of Canada-the
nation's foremost scientific body-said there was insufficient
research into the potential allergic effects and toxicity
of genetically engineered foods. GM foods could cause "serious
risks to human health," the society said.
According to the Washington Post,
the "dearth of studies is the legacy of a U.S. policy
that considers gene-altered plants and food to be fundamentally
the same as conventional ones, a policy some Americans are
starting to question....
"And it is the legacy of broken promises
by the Food and Drug Administration and the Environmental
Protection Agency, both of which have said for the past five
years that they intend to write rules to minimize the chances
that gene-altered food will cause allergies or damage the
environment."
Genetic engineering may involve the transfer of new
and unidentified proteins from one food into another, with
the potential of setting off allergic reactions. And allergies
aren't simply a matter of slight discomfort; they can potentially
result in life-threatening anaphylactic shock.
Without labeling, people with allergies
won't know if they are eating foods that contain genes from
other foods to which they are allergic.
In 1996, scientists were stunned to discover
that soybeans engineered to include protein-rich genes from
the Brazil nut also contained the allergenic properties of
the Brazil nut. Animal studies had not revealed the allergenic
nature of the mutated soybean. The manufacturer halted the
release of the soybean just in time.
But with dozens of new genetically engineered
crops under consideration, scientists believe much more extensive
testing is required to ensure that those who suffer from allergies
won't be affected by these foods.
Scientists also have discovered that Bacillus
thuringiensis (Bt), a bacterium that has been spliced into
millions of acres of corn, potatoes and cotton, may produce
allergies in people.
Science News reported in July 1999
that a study of Ohio crop pickers and handlers shows that
Bt "can provoke immunological changes indicative of a
developing allergy. With long-term exposure, affected individuals
may develop asthma or other serious allergic reactions."
Scientists say genetic engineering may produce new
toxins, with potentially devastating results for humans. In
at least one case, disaster has already happened.
In 1989, a genetically engineered version
of tryptophan, a dietary supplement, produced toxic contaminants.
Before it was recalled by the Food and Drug Administration,
the mutated tryptophan wreaked havoc. Thirty-seven Americans
died, 1,500 were permanently disabled, and 5,000 became ill
with a blood disorder, eosinophila myalgia syndrome.
Genetic engineers use antibiotic "markers"
in almost every genetically modified organism to indicate
that the organism has been successfully engineered. Scientists
believe these antibiotic markers may contribute to the decreasing
effectiveness of antibiotics against diseases.
The journal Microbial Ecology in Health and Disease
reported in 1998 that commercial gene technology may be behind
a recent resurgence of drug- and antibiotic-resistant infectious
diseases. We'll let Dr. Mae-Wan Ho, author of the report (and
author of Genetic Engineering: Dream or Nightmare?),
take over from here. She says:
"At the heart of the issue is horizontal
gene transfer - the transfer of genes by vectors such as viruses
and other infectious agents - which is exploited by genetic
engineers to make transgenic organisms. While natural vectors
respect species barriers, the barrage of artificial vectors
made by genetic engineers are designed to cross species barriers,
thus greatly enhancing the potential for creating new viral
and bacterial pathogens, and spreading drug and antibiotic
resistance. Totally unrelated pathogens are showing up with
identical virulence and antibiotic resistance genes.
"Recent statistics are frightening.
Infectious diseases were responsible for one-third of the
52 million deaths from all causes in 1995. Multi-drug resistant
tuberculosis is now estimated to affect 10 million each year
with 3 million deaths. At least 50 new viruses attacking humans
emerged between 1988 and 1996. Between 1986 and 1996, E. coli
0157:H7 infections increased by 10-fold in England and Wales
and 100-fold in Scotland. Vancomycin resistance rose from
3 percent to 95 percent in San Francisco hospitals in the
four years between 1993 and 1997. And Staphyloccocus (toxic
shock syndrome) is now invulnerable to all known antibiotics.
"The first genetic engineers called
for a moratorium in the Asilomar Declaration of 1975, precisely
because they were afraid of inadvertently creating new viral
and bacterial pathogens. The worst case scenario they envisaged
may be taking shape. Commercial pressures led to regulatory
guidelines based largely on untested assumptions, all of which
have been invalidated by recent scientific findings. For example,
biologically "crippled" laboratory strains of bacteria
can often survive in the environment to exchange genes with
other organisms. Genetic material (DNA) released from dead
and living cells, far from being rapidly broken down, actually
persists in the environment and transfers to other organisms.
Naked viral DNA may be more infectious, and have a wider host
range than the virus. Viral DNA resists digestion in the gut
of mice, enters the blood stream to infect white blood cells,
spleen and liver cells, and may even integrate into the mouse
cell genome.
"'We may only be seeing the tip of
the iceberg,' the scientists state. 'There is an urgent need
to tighten existing regulations.' Instead, the EU is relaxing
the guidelines on both deliberate release and contained use
of GMOs. 'That is an irresponsible move in the light of existing
scientific knowledge.'"
Threats
to the environmentWhen biotech corporations boast
that genetic engineering can do wonders for the environment,
we would do well to consider the source. After all, some of
these companies are the same ones that have invented such
deadly pesticides such as DDT and Agent Orange. These pesticides,
it was promised, would help the environment; instead, they
turned into environmental disasters.
Environmentalists have many concerns about
GE foods. Here are a few:
Cornell University researchers have found that GE corn
may be deadly to the Monarch butterfly. In laboratory tests
in the spring of 1999, the scientists found that nearly half
of Monarch caterpillars that ate milkweed leaves dusted with
GE corn pollen died within four days. The surviving Monarchs
that ate the genetically mutated corn pollen were much smaller
and had smaller appetites than the control Monarchs, which
ate normal corn pollen or no pollen at all.
In 2000, Iowa State University scientists
found that plants growing in and near cornfields are being
dusted with enough GE pollen to kill monarch caterpillars
that feed on them.
Already, GE corn is being grown on 20 million
acres of American farmland, right in the heart of Monarch's
migratory route between Mexico and Canada.
And scientists worry that there may be
additional surprising scientific discoveries down the road.
Many of the new GE crops, such as Roundup Ready soybeans,
are designed to allow farmers to spray heavier doses of pesticides
on their land. These pesticides inevitably will find their
way into our water and food supply, endangering humans and
wildlife.
New Scientist magazine reports that
many farmers that have converted to GE production use as many
pesticides as their conventional counterparts, while some
GE farmers now use more pesticides.
And one of Britain's leading safety experts,
Malcolm Kane (former head of food safety at the supermarket
chain Sainsbury's), has revealed that the limits on pesticide
residues in soy had been increased 200-fold to help the GE
industry. He warned that higher pesticide residues could appear
in a wide variety of foods, ranging from breakfast cereals
to biscuits.
When Scottish Parliament member Robin Harper learned
that Scottish scientists were experimenting with genetically
modified salmon that grow at four times the normal rate, he
was horrified, and called for a ban on all genetic engineering
experiments.
"We should be extremely concerned
about genetically modified fish because of the danger that
they could escape into the wild," he said. "It's
a similar, if not even more dangerous threat, to that we are
facing with GM plants. If a GM fish escaped or was released
accidentally in to the wild it could never be recaptured.
This fish could breed with wild populations and devastate
the existing natural balance with its modified behavior.
"There can be no doubt as to the huge
threat GM fish would be to fish stocks wherever they were
released in the World's oceans. This fish, if it escaped into
the North Atlantic, could do untold damage to the ecology
both of the north Atlantic and Scottish salmon rivers."
Like Harper, many scientists are concerned
about the widespread release of genetically modified organisms
(GMOs) into the environment. In the United States, millions
of acres of land have been planted with GE crops. Scientists
fear that GMOs will be spread, by bird, insect or wind, to
non-GE crops--and to the wilderness. And unlike other kinds
of waste, genetic contamination cannot be cleaned up, or contained.
In May, 2000, Professor Hans-Hinrich Katz, a leading German
zoologist, released research that shows that genes used to
modify crops can jump to other species and cause bacteria
to mutate. Katz found that the gene used to modify oilseed
rape had transferred to bacteria living in the guts of honey
bees.
"These findings are very worrying
and provide the first real evidence of what many have feared,"
says prominent genetic engineering critic and scientist Dr.
Mae-Wan Ho.
"Everybody is keen to exploit GM technology,
but nobody is looking at the risk of horizontal gene transfer.
We are playing about with genetic structures that existed
for millions of years and the experiment is running out of
control."
Some scientists fear that the extensive planting of
genetically engineered crops will lead to a new class of "superweeds"
that are resistant to pesticides. The largest class of genetic
engineered foods is pesticide-resistant crops, such as Roundup
Ready soybeans. The problem is that newly created transgenes
may be spread unintentionally--by bird, insect or wind--from
target crops to related weed species. The weeds then also
pick up resistance to the pesticide.
Nature magazine reported in 1996,
for example, that herbicide-resistant GE oilseed rape, released
in Europe, has spread to several wild relatives.
In one especially macabre application of GE technology,
scientists seek to develop "terminator" tree farms.
The trees would be engineered not to reproduce, and they would
be designed to secrete toxic chemicals through their leaves
that would kill leaf-eating insects. The trees also would
be engineered to include pesticide resistance, meaning that
ground flora could be wiped out easily. Critics say the trees
might grow faster than before, but they'd be devoid of bees,
butterflies, birds and squirrels that depend on pollen, seed
and nectar.
The terminator tree farms highlight a growing
concern among scientists: the threat genetically engineered
crops pose to biodiversity. Scientists estimate that by the
year 2000, the world will have lost 95 percent of the genetic
diversity present in agriculture 100 years earlier. GE crops
are developed from the same monoculture varieties that giant
agribusinesses have planted in the latter half of this century,
and will only exacerbate the problem.
Moreover, pesticide-resistant crops will
allow the application of increasing amounts of powerful pesticides.
These pesticides often kill more than the targeted weeds;
they frequently kill beneficial plants outside their intended
range.
7. Damage to the soil
Scientists are concerned that genetically mutated crops may
damage the soil. Researchers for Nature magazine reported
in December that some types of GE crops may be leaking powerful
toxins into the soil.
Many GE crops, such as corn and potatoes,
have been engineered to produce poisons or toxins to fight
pests that eat their leaves and stems. Researchers fear that
beneficial soil organisms also may be killed, and that some
insects may become resistant to the toxins.
Other researchers have revealed that
lacewings that ate corn borers reared on GE corn had also
died, increasing speculation that these crops are harming
beneficial organisms.
British researchers in 2000 reported that the use of
genetically engineered crops modified to tolerate herbicides
may severely cut bird populations on farms. Professor Andrew
Watkinson and colleagues from the University of East Anglia
in Norwich found that bird populations could decline as much
as 90 percent in some areas where herbicide-tolerant crops
have been sown.
Biotech firms assure us there's nothing to worry about.
Genetically engineered foods, they say, will save the environment.
But it's a story we've heard before. In
the mid-1900s, giant agribusinesses took the biological and
chemical weapons from two world wars and turned them into
pesticides and herbicides. They promised a wondrous new agricultural
era of bigger yields and bug-free produce. It was only decades
afterwards that scientists began to realize the scope of the
environmental devastation wrought by the explosive growth
of the pesticide industry.
In the 1960s, scientist Rachel Carson's
epic, Silent Spring, awakened a generation to the dangers
of dioxin and other manmade chemicals in the environment.
But it wasn't until 30 years later that scientists began to
understand the extent of the problem. Now we know that pesticides
and other manmade chemicals are tampering with sexual development
and reproduction, in many animal populations and humans as
well.
The discovery that genetically engineered
corn might be deadly to Monarch butterflies came as a shock
to biotech advocates. If biotech companies continue with their
massive experiment, what will our scientists tell us 50 years
from now?
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