Since 1996, as more and more genetically
modified crops took root, a growing number
of stakeholders around the world began to
voice their concerns about the possible
negative impacts of GMOs and their
contribution to an unsustainable model of
agriculture. Opposition is particularly
heated on three grounds: environmental,
health and socioeconomic.
environmental
pitfalls
Scientific research is raising
increasing concerns about the potential
environmental risks associated with GM
crops, including:
gene transfer:
Genes from GM crops can be (and have been)
transferred to wild relatives of these
crops. In its report “Genetically Modified
Organisms (GMOs): The significance of gene
flow through pollen transfer”, the European
Environmental Agency states that oilseed
rape is “high risk” and sugar beet “medium
to high risk” for pollen mediated gene flow
from crop to crop and from crop to wild
relative.
pest resistance:
Insect pests may develop resistance
to GM crops engineered to contain Bt
toxins, shortening the useful life of such
crops and compromising the effectiveness of
existing Bt insecticides. This has serious
implications for the organic community and
other farmers using integrated pest
management (IPM) and other sustainable
agriculture approaches. The naturally
occurring Bt pesticide that these non-GM
farmers benefit from becomes useless as
insects become resistant.
adverse impacts for non-target
organisms:
Pest-resistant crops
may have adverse impacts for beneficial
insects and other invertebrate populations.
In 1999, scientists at Cornell University
revealed that pollen from genetically
engineered Bt corn could kill Monarch
butterflies. The findings of this lab study
have since been confirmed in an ongoing
field study at Iowa State University . In
addition to the monarch butterflies, there
is evidence showing that Bt crops may also
affect beneficial predator insects such as
lacewings and ladybirds when they eat
insects that have been feeding on
genetically engineered plants. A 2001 US
National Academy of Sciences study affirmed
that the Bt 176 variety of GM corn was
likely harmful to Monarch butterflies.
intensification of chemical
dependence:
Herbicide-tolerant crops have
contradicted the claim that genetic
engineering helps the environment. Instead
of moving farmers away from their
dependence on chemical pesticides, these
crops actually encourage pesticide use – a
threat to our food and drinking water and
to wildlife. Indeed, a 1999 US report,
which reviewed more that 8,200
university-run field tests on herbicide
resistant crops, found that farmers
planting Roundup Ready soybeans used two to
five times more herbicide than did
conventional soybean farmers.
creation of
‘superweeds':
It has been shown that herbicide
resistance genes can spread to related
plants via pollen carried by bees or by the
wind. Researchers have found evidence for
this in the case of canola and sugar beet
in Europe . In Canada , canola resistant to
three different herbicides resulted from
uncontrollable crossbreeding between plants
that were each resistant to one herbicide.
These ‘superweeds' can be difficult and
expensive for farmers to eradicate. They
could potentially displace existing species
of plants, destroying local ecosystems and
threatening biodiversity. health concerns
Some of the main concerns about the
consumption of GM crops are:
new allergies:
GM crops could introduce new
allergens into foods that sensitive
individuals would not know to avoid. The
problem is unique to genetic engineering
because it alone can transfer proteins
across species boundaries into completely
unrelated organisms. Genetic engineering
routinely moves proteins into the food
supply from organisms (such as viruses)
that have never been consumed as foods.
Thus importing proteins, particularly from
nonfood sources, is a gamble with respect
to their allergenicity .
antibiotic-resistance
:
The presence of antibiotic resistance
genes engineered into foods (these genes
are used by biotech companies as ‘markers'
to identify new traits in the engineered
product) could reduce the effectiveness of
disease-fighting antibiotics when they are
taken with meals. This concern grew in 2002
when British scientific researchers
demonstrated for the first time that
genetically modified DNA material from
crops is finding its way into human gut
bacteria, raising potentially serious
health questions. If genetic material from
these marker genes can find its way into
the human stomach, then people's resistance
to widely used antibiotics could be
compromised.
increased toxins in
plants:
The addition of new genetic material
through genetic engineering could also
increase levels of toxic substances within
plants.
socioeconomic
issues
corporate control
:
The corporations that market GMOs and the
associated chemicals seek to control
agriculture and food production by buying
up seed companies, patenting seeds and
locking farmers into exclusive agreements.
If this strategy succeeds, it will
dramatically reduce agricultural
biodiversity and lead to more
industrialized and unsustainable
farming.
no benefit to consumers:
The majority of GMOs that have been
authorized or are pending approval are
either herbicide-tolerant or
insect-resistant. They pose real problems
for the environment and offer absolutely no
benefit to the consumer, as they are
neither cheaper nor better quality than
conventional foods.
British doctors have urged a halt to
genetically modified crop trials. In
November 2002, the British Medical
Association, which has a membership of over
120,000 and represents more than 80 percent
of British doctors, said that there "has
not yet been a robust and thorough search
into the potentially harmful effects of GM
foodstuffs on human health.”
sources:
The Union of Concerned Scientists:
www.ucsusa.org/food_and_environment/biotechnology/index.cfm
British Medical Association:
www.bma.org.uk
more information
:
FoE US website:
www.foe.org/camps/comm/safefood/gefood/
index.html
European Environmental Agency:
“Genetically Modified Organisms (GMOs): The
significance of gene flow through pollen
transfer”, March 2002:
http://reports.eea.eu.int/environmental_issue_report_2002_28/en
GM genes found in human gut”, The
Guardian, 17 July 2002 :
www.guardian.co.uk/Archive/Article/0,4273,4
463029,00.html
Research on effects of Bt maize on Monarch
butterflies,”Nature, May,1999.
www.nature.com
