By Claire Robinson
[a slightly edited version of this article was originally published in The Ecologist - www.theecologist.org]
The United States government has given the go-ahead for a test plot of genetically modified (GM) eucalyptus trees in Alabama. For the first time, these trees will be allowed to flower and set seed, opening the door to potential widespread contamination of the American South. Some of the trees are genetically engineered by biotech firm ArborGen for cold tolerance, while others are engineered with 'confidential' traits. Published articles and industry reports indicate that these traits may include the ability to kill insects and reduced lignin. Lignin gives strength to trees and enables them to take up water.
The permit for the flowering GM eucalyptus was approved by APHIS (the Animal Plant Health Inspection Service, a sub-department of the US Department of Agriculture). The approval follows APHIS's grant of non-regulated status for the GM pox-resistant 'Honeysweet' plum, which the USDA itself helped develop. Non-regulated status is given on the basis that APHIS has decided that the plant does not present a risk of introduction or dissemination of a plant pest. Deregulation of the GM plum marked the first commercial release of a GM temperate tree in the US. It occurred in spite of the fact that public comments against the proposal to deregulate the plum outnumbered those in favour by 100 to 1.
APHIS has also approved the largest-ever release in the US of GM poplars. Some are modified for reduced stature and light response, others for altered lignin content, and others to result in a male-sterile plant.
This raft of GM tree approvals confirms that the trend in the US regulatory system is to rubber-stamp applications for release with disregard for the risks. Anne Petermann, co-director of the Global Justice Ecology Project, says, 'There is no independent risk assessment going on in the US or anywhere else with regard to GM trees.'
As far as eucalyptus is concerned, even to introduce it in its non-GM form could be foolhardy. Eucalyptus is a species of the tropics and subtropics, and is not native to the US. In countries where it has been introduced, it has become invasive. The fact that some of ArborGen's GM eucalyptus trees are modified to be cold tolerant will extend their ability to colonize. There is no way of knowing how this and the eucalyptus’s other GM traits (which ArborGen will not reveal) may impact forests and wildlife.
Another problem with GM eucalyptus trees that APHIS ignores is the risk to people and animals. The Global Justice Ecology Project has uncovered evidence that one of the eucalyptus species engineered into the GM version is host to a deadly pathogenic fungus called Cryptococcus gattii, which causes fatal fungus meningitis in people and animals that inhale its spores. Cases are increasing worldwide, possibly coinciding with the spread of introduced eucalyptus. Two recent studies show that the fungal human pathogen is common in eucalyptus and that it is endemic in the Northwest US and British Columbia, Canada. APHIS ignored the fact that eucalyptus poses a threat as a plant pest spreading a human pathogen. It has dismissed the warnings of scientists such as Dr Joseph Heitman, director of the Center for Microbial Pathogenesis at Duke University Medical Center and an expert on Cryptococcus, who said, 'Introducing large numbers of eucalyptus trees in the United States has the potential to provide a suitable habitat for Cryptococcus gattii.'
A major reason why regulators are bowing to industry pressure to commercialize GM trees is that they are claimed to offset carbon emissions, and thus qualify for subsidies under the Kyoto Protocol's Clean Development Mechanism. In addition, the rising demand for biofuels has opened up an opportunity for proponents to rescue GM crops from chronic market failure by promoting them as energy crops.
Unfortunately, energy crops, including GM trees, are far from sustainable. The United Nations is one of several bodies that have pointed out that the rush to energy crops threatens food shortages and increased poverty. Worldwide grain shortages have already been blamed on agricultural land being given over to biofuel crops. The UN report also says biofuel crops are not guaranteed to reduce greenhouse gas emissions. Biofuels result in some reductions in emissions compared to petroleum fuels, it says, but this is provided there is no clearing of forest or peat that store centuries of carbon. In reality, deforestation is already speeding up in Brazil, Malaysia, and Indonesia to make way for palm oil and other plantations to feed the new biodiesel market.
The traits engineered into GM trees bring their own environmental problems. Sterility technology as used in GM poplars is designed to make the trees male-sterile by making the pollen non-viable. It is increasingly used as a selling point by the GM industry on the grounds that it will prevent GM contamination of conventional plants. However, it is a 'leaky' technology, in that some viable pollen is produced. Thus the male sterility trait could spread to contaminate non-GM trees, and could lead to sterile forests.
Bt trees, in which a pesticide is engineered into every cell, are toxic to insects. Evidence is growing that Bt crops are also toxic to other non-target organisms, such as animals that graze on them or feed on the insects that have ingested the Bt. Bt crops also infect soil, leaving it toxic to other plants. Trees have life-cycles of 100 years or more, so Bt tree plantations will be sources of toxicity for many years to come.
Low-lignin trees are of particular value to the biofuels industry. Anne Petermann explains, 'Since cellulose is the material of interest in trees in the manufacture of cellulosic ethanol, and lignin gets in the way of accessing this cellulose, genetically engineering trees for higher cellulose and reduced lignin content is of great economic interest. I would venture it unlikely that industry would pursue trees for cellulosic ethanol without them being genetically engineered.' The problem with low-lignin trees is that half their strength has been removed, making them vulnerable to environmental stresses such as high winds and pest attack. The tendency of GM traits to leak into ecosystems raises the prospect of disastrously weakened forests unable to cope with increasingly extreme weather. And once fallen, low-lignin trees decompose more rapidly, returning carbon dioxide to the atmosphere at an accelerated timescale and thereby negating any supposed greenhouse gas benefits.
In spite of the hype surrounding the use of wood for biofuels, the technology does not yet exist to do it efficiently. Probably, it cannot be done without using GM enzymes. For this reason, the US Department of Energy's Joint Genome Institute is involved in a project to genetically engineer the enzyme from the gut of a termite to aid the cellulose digestion process. As Anne Petermann says, 'Imagine the impact on forests if that got loose smoehow.' But it seems that when it comes to GM trees, our regulators would prefer not to imagine, or even to exercise common sense.
1.USDA Approves 1st Flowering GE Tree (Eucalyptus), APHIS (Animal and Plant Health Inspection Service) notification, http://www.stopgetrees.org/article.php?story=20070716121113880
2.National Effort Launched to Stop Genetically Engineered Eucalyptus Plantations in US Southeast, http://aeconline.wagdc.com/?sn=367
3.Transgenic Plum Gets USDA Non-regulated Status Based on False Claims of Safety, http://www.i-sis.org.uk/TransgenicPlumUSDA.php
4.Unregulated Release of GM Poplars and Hybrids, http://www.i-sis.org.uk/GMpoplarsandhybrids.php
5.Anne Petermann, personal communication 6.U.S. Health & Enviro Agencies Asked to Investigate Potential Link Between Pathogenic Fungus & Introduced GE Eucalyptus, http://www.stopgetrees.org/article.php?story=20070614090301897
Personal communication with Prof. Joe Cummins. Joe Cummins cites 2 studies to support his statement that 'the fungal human pathogen is common in eucalyptus' and 'endemic' in the Northwest US and British Columbia, Canada, respectively: (i) Gugnani HC et al, Isolation of Cryptococcus gattii and Cryptococcus neoformans var. grubii from the flowers and bark of Eucalyptus trees in India, Med Mycol. 2005 Sep;43(6):565-9; (ii) MacDougall L et al, Spread of Cryptococcus gattii in British Columbia, Canada, and detection in the Pacific Northwest, USA, Emerg Infect Dis. 2007 Jan;13(1):42-50.
7.U.S. Health & Enviro Agencies Asked to Investigate Potential Link Between Pathogenic Fungus & Introduced GE Eucalyptus, http://www.stopgetrees.org/article.php?story=20070614090301897
8.Moratorium on all GM Trees and Ban on GM Forest Trees, http://www.i-sis.org.uk/Moratorium_on_all_GM_Trees.php
9.Global rush to energy crops threatens to bring food shortages and increase poverty, says UN, http://www.gmwatch.org/archive2.asp?arcid=7849
10.ENERGY-CHINA: Biofuels Eating Into Food Grain Stocks, http://ipsnews.net/news.asp?idnews=35905
11.Biofuels: Biodevastation, Hunger & False Carbon Credits, http://www.i-sis.org.uk/BiofuelsBiodevastationHunger.php
12.Moratorium on all GM Trees and Ban on GM Forest Trees, http://www.i-sis.org.uk/Moratorium_on_all_GM_Trees.php
13.Bt Cotton & Livestock effects: CSA meets farmers & officials in Adilabad district', http://www.gmwatch.org/archive2.asp?arcid=7614
14.Genetically-modified Bt cotton a cropper: Study, http://www.gmwatch.org/archive2.asp?arcid=5103
15.Anne Petermann, personal communication 16.Moratorium on all GM Trees and Ban on GM Forest Trees, http://www.i-sis.org.uk/Moratorium_on_all_GM_Trees.php
17.Termite Gut Bacteria as Allies in Biofuel Production, http://www.cedab.it/newsletter_ISAAA.asp?IDnews=103#ancora9