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GE Forest Trees –
The Ultimate Threat
Dr. Mae-Wan Ho and Prof. Joe Cummins
The ultimate threat
Genetically modified (GM) forest trees do not attract the same
immediate health concerns as GM food crops. But in reality, they
pose an even greater threat than GM crops because they impact
directly on natural forests that are essential for the survival of
our planet.
World status of GM forest trees
Most genetic modification of forest trees have been done by
Agrobacterium-mediated DNA transfer; but bombardment with
DNA-coated particles, or ‘biolistic transformation’, has also
been used. Of the 205 permit applications listed at the end of
2003, 73.5% originated in the USA, 23% in other OECD member
nations (in particular, Belgium, Canada, France, Finland, New
Zealand, Norway, Portugal, Spain and Sweden) and 3.5% elsewhere (Brazil,
China, Chile, South Africa and Uruguay) [1]. Four
traits account for 80% of the permit applications: herbicide
tolerance (32%), marker genes (27%), insect resistance (12%), and
lignin modification (9%). Of the tree species involved, Populus,
Pinus,
Liquidambar (Sweet Gum Tree) and Eucalyptus account for 85% of
applications.
Although commercial interest was low during the first ten years of
GM trees development, it has steadily increased since the late
1990s. By the end of 2003, 45% of the permits submitted were from
industry, mostly for transgenic poplars. But to-date there has not
been a concerted push for commercialisation of GM trees except in
China, where more than one million GM trees have been planted in
“reforestation” initiatives since commercialisation was
approved by The Chinese State Forestry Administration in 2002 (see
“GM trees get lost”, this series).
Several companies, including Weyerhaeuser, Shell and Monsanto, at
one time involved in GM tree research have since pulled out
because it was not economically attractive [2]. However, the
decision reached in December 2003 at the ninth Conference of the
Parties to the UN Framework Convention on Climate Change to allow
Northern companies and governments to establish plantations of GM
trees in the South under the “Clean Development Mechanism”
might be the subsidy that GM proponents need to make GM trees seem
economically attractive.
The overriding importance of forests
Forest trees are long-lived. Their root system is extensive,
interacting with countless species in the soil biota that are
crucial for recycling, storing and keeping nutrients within the
forest ecosystem.
Above ground, forest trees provide shelter, home and food for
indigenous peoples and between 1.5 to 2 million species of insects,
birds, mammals, other plants, epiphytes, fungi and bacteria.
All human beings are dependent on forests in one way or another,
for clean water, habitat, food, medicinal plants, and as
recreational and spiritual sanctuaries.
Most of all, forests, especially the tropical rainforests, are
essential for the water cycle that brings rain to crops; and for
regulating the temperature of the earth, preventing places from
getting too hot or too cold. Forests absorb carbon dioxide and
produce oxygen; in that respect they are the ‘lungs’ of the
living earth (see “Why Gaia needs rainforests”, SiS 20).
Losing forests to GM tree plantations would spell ecological
disaster for our planet, especially as global warming is fast
accelerating.
GM trees anathema to forest ecosystems
GM trees are designed for large monoculture plantations anathema
to the bio-diverse natural forest ecosystems. Local people’s
names for industrial tree plantations are revealing [2].
Eucalyptus is the “selfish tree”, because eucalyptus
plantations remove nutrients from the soil and consume so much
water that farmers cannot grow rice in neighbouring fields.
Mapuche Indigenous People in Chile refer to pine plantations as
“planted soldiers”, because they are green, in rows and
advancing. In Brazil, tree plantations are “green deserts”,
and in South Africa, “green cancer”. Throughout the Global
South, organisations and networks are actively opposing industrial
tree plantations on their land. GM trees will intensity both the
problems of industrial plantations and the opposition from
indigenous peoples.
A joint report by the World Rainforest Movement (WRM) and Friends
of the Earth International (FoEI) [2] says that the scientists
claiming to “improve” trees by genetic modification are in
reality working to
“improve the profitability of the businesses” funding their
research.
It continues:
“But from a biological perspective there is no improvement
whatsoever. Is a tree with less lignin better or worse than a
normal one? It is clearly worse, given the resulting loss of
structural strength, which makes it susceptible to extensive
damage during windstorms. Is an herbicide-resistance tree an “improvement”?
It is not, for it allows extensive herbicide spraying that affects
the soil on which it stands, at the same time as it destroys local
flora and impacts on wildlife. Is a flowerless, fruitless and
seedless tree of any use to living beings? It does not provide
food to myriad species of insects, birds and [other] species that
depend on these as food. Is a tree with insecticide properties an
improvement? It is a dangerous hazard to many insects species,
which are themselves part of larger food chains.”
GM trees violate international conventions
The WRM report points out that GMOs in general and GM trees in
particular, are a clear violation of the Convention on Biological
Diversity, which obliges governments to take a precautionary
approach towards GMOs that may cause serious damage to
biodiversity. GM trees also violate the spirit of
the United Nations Forum on Forests, which was set up to protect
the world’s forests.
Unfortunately, the inclusion of GM trees within the framework of
the Kyoto Protocol’s Clean Development Mechanism means that the
Climate Change Convention not only supports the expansion of
monoculture tree plantations, but GM tree plantations supposed to
act as better “carbon sinks”.
The WRM, FoEI International and ECOTERRA Intl. are calling on all
governments, especially the Parties to the Framework Convention on
Climate Change and its Kyoto Protocol, to ban the release of GM
trees. The campaign to ban GM trees was launched in January 2004
by the Finnish People’s Biosafety Association and the Union of
Ecoforestry (see “No to GM Trees”, SiS 23).
Transgene contamination inevitable and unavoidable
Forest trees are tall, long-lived and produce abundant pollen and
seeds that can be carried far and wide. Forest trees also
reproduce asexually, sending out clones that spread long distances
from the mother plant, thus promoting further transgene
contamination. Contamination of native trees by GM trees is hence
inevitable and unavoidable.
Low lignin GM trees increase destruction of forests &
livelihoods
Low lignin trees are more susceptible, not only to storm damage
but also to attacks by insects, fungi and bacteria (see “Low
lignin GM trees and forage crops”, SiS 23).
The reduced-lignin trait spreading to native forest trees will
make them susceptible to storm, attack by pests, and fungal and
bacterial diseases. Insect pest populations will also increase as
a result.
While low lignin GM tree plantations may benefit the paper
industry, they will destroy local livelihoods, forcing people to
move away, some of them to new forests where they clear more land
for farming [2]. Tree plantations often follow the destruction of
native forests. In Sumatra, for example, vast areas of forests
have been cleared to feed pulp and paper mills; the clear-cut
forests being replaced by acacia plantations. The argument that
planting faster growing GM trees is “growing more wood on less
land” is misleading. Producing more fibre for the pulp industry
will not change the demand for high quality decorative tropical
hardwoods for the construction industry, which come largely from
native forests.
Also, the demand for timber is not the only cause of deforestation;
road-building, dams, cash crops (such as soya in Brazil and
Argentina) or cattle ranging, mining and oil extraction all
contribute to destroying native forests, and creating GM tree
plantations will do nothing to stem the destruction.
Fast growing GM trees will consume even more water than current
industrial tree plantations, draining the already depleted
aquifers and impacting on surrounding forests.
Most of the pulp produced in the South is exported to the North.
Per capita paper consumption in Germany is 70% that in the US.
Vietnam consumes on average 2% of the amount of paper consumed in
the US, despite the fact that literacy rates in the US, Germany
and Vietnam are almost identical [2]. Nearly 40% of the paper is
used for packaging, and 60% of the space in the US newspaper is
taken up by adverts. According to Jukka Hamala, CEO of Stora Enso
- the second biggest paper, packaging and forest products company
in the world, whose sales totalled 12.4 billion in 2004 -
the key factor in increased paper demand was increased spending on
advertisements in newspapers and magazines. Thus, increasing paper
consumption is neither necessary nor desirable.
Fast growing GM trees exacerbate climate change
The argument that planting GM trees can reverse climate change is
also fallacious. Japanese car manufacturer Toyota started field
trials of trees genetically modified to absorb more carbon in
1993. Unfortunately, while carbon absorption increased, it was
accompanied by a dramatic increase in
water consumption.
Tree plantations are much less effective in sequestering carbon
than the native forest ecosystem. The biodiverse native forest
ecosystem is an effective carbon sink. It has been estimated that
the neo-tropical forests of Central and South America sequesters
at least one tonne of carbon per
hectare per year in biomass increase above ground. (It is possible
that additional carbon is sequestered in the soil.) In contrast,
destroying a hectare of forest releases 200 tonnes of carbon (see
“Why Gaia needs rainforests”, SiS 23).
Fast-growing reduced-lignin trees will also rot more readily,
returning carbon dioxide more rapidly to the atmosphere, thereby
exacerbating global warming instead of ameliorating it.
Researchers used a NASA thermal infrared multispectral scanner
from the air to assess energy budgets of experimental forests in
Oregon in 1989 [3]. They found that a clear-cut forest area had a
surface temperature of 51.8C, hotter than a nearby quarry, which
registered 50.7C. The Douglas fir plantation with mature trees
registered 29.9C, compared to 29.4C over the natural Douglas fir
forest regrowth; while the coolest temperature of 24.7C was found
over the 400 year-old forest. The cooling effect of the natural
forest ecosystem is not only important for alleviating global
warming; it is also a significant indicator of sustainability [4].
Insecticidal GM trees destroy biodiversity
There is no doubt that the insecticidal GM trees will kill many
insects, both target pest species and non-target species; that is,
until the pests develop resistance within six or seven years,
according to the estimate of Liu Xiaofeng from Henan Agriculture
Department, a scientist critical of the GM cotton planted in China
(see “GM cotton fiascos around the world”, SiS25). At that
point, more insecticides will have to be used, especially as new
kinds of pests will have appeared.
The far greater threat to biodiversity is the spread of the
insecticidal traits to natural forests. Laboratory feeding
experiments have shown that Bt toxins produced in GM crops can
harm beneficial predators that feed on insect pests, even when the
pests themselves are not affected by the toxins [5]. One class of
Bt toxins (Cry1A) was found to harm butterflies, lacewings and
mice. Another class (Cry3A) acts against insects belonging to the
Order Coleoptera (beetles, weevils and stylopids) [6], which
contains some 28 600 species. Bt toxins are known to leach out of
the roots into the soil, with potentially huge impacts on the soil
biota. Reduction of insect populations will in turn impact on
birds and mammals that feed on insects.
Herbicide-tolerant GM trees make green deserts
GM trees have been made tolerant to broad-spectrum herbicides that
kill all other plants. If that is not bad enough, they are also
harmful to all species of animal wildlife including human beings (reviewed
in The Case for a GM-Free Sustainable World, ISP Report www.indsp.org
). Plantations of herbicide-tolerant GM trees are really green
deserts, and collateral damage to nearby forests and crops from
spraying herbicides is inevitable, as is the pollution of drinking
water.
Glyphosate is the most frequent cause of complaints and poisoning
in the UK. Disturbances of many body functions have been reported
after exposure at normal use levels. It nearly doubled the risk of
late spontaneous abortion, and children born to users had elevated
neurobehavioral defects. Roundup (Monsanto’s formulation of
glyphosate) caused cell division dysfunction that may be linked to
human cancer. Glyphosate caused retarded development of the foetal
skeleton in laboratory rats. It inhibits the synthesis of steroids
and is genotoxic in mammals, fish and frogs. It is lethal and
highly toxic to earthworms.
Glufosinate ammonium is linked to neurological, respiratory,
gastrointestinal and haematological toxicities and birth defects
in humans. It is toxic to butterflies and a number of beneficial
insects,
also to the larvae of clams and oysters, Daphnia, some fresh water
fish such as the rainbow trout. It inhibits beneficial soil
bacteria and fungi, especially those that fix nitrogen.
Health hazards
The health hazards of GM trees are common to those of other GM
crops, but they will be exaggerated. Two of these in particular
are worth mentioning. Agrobacterium, used in the vector system for
creating many GM trees, is a soil bacterium that causes tumours to
grow on infected plants and is now known to be capable of
transferring genes into animal and human cells (See “Common
plant vector injects genes into human cells” http://www.i-sis.org.uk/Agrobacterium.php).
Scientists have warned that the Agrobacterium is extremely
difficult to eradicate from the transgenic
plants created, and can therefore serve as a potential vehicle for
unintended horizontal gene transfer to soil bacteria and all other
species, including human beings, that come into contact with the
transgenic crops. This danger is greatly increased in GM trees,
especially on account of its extensive root system. The
rhizosphere – plant root system - is a known hotspot for
horizontal gene transfer.
The potential of Agrobacterium to mediate horizontal gene transfer,
and the resulting hazards of spreading antibiotic resistance
marker gene to pathogens; creating new bacteria and viruses that
cause diseases; and causing cancer in animals including humans
were reviewed in Chapter 11 of
ISP report (www.indsp.org).
Another source of health hazard is the Bt toxins and other
transgenes, which could be spread far and wide in the pollen of GM
trees. All Bt toxins used as transgenes as well as the transgenes
conferring glyphosate tolerance were found to have similarities to
known allergens, and are hence suspected allergens (see “Are
transgenic proteins allergenic?” ISIS report 05/01/ 2005 http://www.i-sis.org.uk/ATPA.php).
References
1. Lang C. Genetically Modified Trees The ultimate threat to
forests. World Rainforest Movement and Friends of the Earth,
December 2004 http://www.wrm.org.uy/subjects/GMTrees/text.pdf
2. Van Frankenhuyzen K and Beardmore T. Current status and
environmental impact of transgenic forest trees. Can J For Res
2004, 1163-1180.
3. Luvall JC and Holbo HR. Measurements of short term thermal
responses of coniferous forest canopies using thermal scanner data.
Remote Sensing and the Environment 1989, 27, 1-10.
4. Ho MW. Are sustainable economic systems like organisms? In
Evolution, Development and Economics (P. Koslowski, ed.),
Springer-Verlag, Berlin, 1998b.
5. Dutton A, Klein H, Romeis J and Bigler F. “Uptake of Bt-toxin
by herbivores feeding on transgenic maize and consequences for the
predator Chrysoperia carnea”, Ecological Entomology 2002, 27,
441-7.
6. Wu S-J, Koller CN, Miller DL, Bauer LS and Dean DH. Enhanced
toxicity of Bacillus thuringiensis Cry3A d-endotoxin in
coleopterans by mutagenesis in a receptor binding loop. FEBS
Letters 2000, 473, 227-232.
7. Reviewed in Ho MW and Lim LC. The Case for a GM-Free
Sustainable World, ISP Report, ISIS & TWN, London & Penang,
2003.
Dr Maewan Ho is editor of Science in Society (SiS) magazine and
scientific advisor to The Third World Network. For more
information on her work
visit: www.i-sis.org.uk
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please join ECOTERRA's ANTI-GE caampaign
send an e-mail to AntiGE "at" ecoterra.net
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please join the Global Anti-GE-Tree campaign:
http://elonmerkki.net/forestforum
No right for contamination
Global Ban on GM trees
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pls see also:
Global Justice Ecology Project http://www.globaljusticeecology.org
GMWATCH http://www.gmwatch.org
BioWatch SA http://www.biowatch.org.za
GRAIN http://www.grain.org
Independent Scientist Panel ISP http://www.indsp.org
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ECOTERRA Intl.
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