Today's Topics in AgBioView.
Archived at http://www.agbioworld.org/listarchive/list.php
* Foods from Genetically Improved Crops in Africa
* GM Crops Vital for Hungry India, Says Experts
* European Leaders Urged to Take a Position on Gene Modification
* Scientists Urge Mexico To Support Biotech Crops, Products
* On Patagonia and DNA Uptake by Humans
* Inappropriate Comments (Re The Face of Terrorism)
* Value-Added Biotech Crops On Horizon
* The Biotech Boom: Creating Frankenforests
* Indonesia to Expand Bt Cotton
* Seed v Seed: Mass-producing Drugs
* Of Maize and Men: Is The Endorsement of GM Crops Science or Politics?
y around the world for the recent American tragedy)
Foods from Genetically Improved Crops in Africa
A 16-page colorful and informative brochure on agricultural biotechnology in Africa has been now posted on the AgBioWorld website at
It is a very well written booklet with colorful graphics. Please forward this information to others who may benefit from it. The brochure will certainly be useful in your public lectures and class room teaching. The brochure was developed by Dr. Maarten Chrispeels of the San Diego Center for Molecular Agriculture and Dr. Jocelyn Webster of AfricaBio. Please note that it is a '.pdf' file and requires a free software Adobe Acrobat Reader that will probably in your computer; if not, it can easily be downloaded at http://www.adobe.com
GM Crops Vital for Hungry India, Says Experts
New Indian Express, Sept 14, 2001 http://www.newindpress.com/
CHENNAI: Genetically Modified (GM) crops have significant commercial viability but caution needs to be exercised while introducing them to the Indian agricultural scenario, say experts. The advantages of reduced expenditure on pesticides, higher yield and enhanced nutrition may be offset by unacceptable pricing of seeds, control of technology by multinationals and the "unpredictable consequences of genetic modification,'' biotech watchers at the SPIC Science Foundation said.
Transgenic or GM crops contain genes which have been artificially inserted rather than through pollination. The inserted gene sequence may come from another plant or from a completely different species. "GM crops are more important for us in India than for those in the western world who have enough to eat,'' says Dr. Joseph Thomas, Director, SPIC Science Foundation. He said GM crops had proved pest resistant, especially rice, maize and several vegetables. "Their use can save us enormous amounts of money that will be otherwise spent on pesticides,'' he said. Dr Thomas said that rice crops had been traditionally ravaged by the yellow stem borer pest and the rice blast disease.
Despite nearly 11 million hectares under cotton cultivation, Tamil Nadu farmers are struggling with low productivity. About 50 per cent of the total quantity of pesticides used in India are applied on cotton crops, he said. "In such a scenario, why not opt for GM crops?'', says Dr. Thomas.
Nutrition is another potential area. GM crops enriched with Vitamin A and iron can be developed. Nutrition levels in Tamil Nadu are extremely low with 28.2 per cent of households consuming less than 1890 kcal per consumer unit per day and 61.3 per cent consuming less than 2400 kcal per consumer unit per day. These statistics (National Sample Survey Organisation, 50th round, 1993-94) are shocking as the internationally accepted average calorie consumption is 2700 kcal.
More than 100 million acres are under GM crops worldwide. The United States alone has nearly 75 million acres under these crops. Fifty per cent of soybean and 25 per cent of corn produced in the US are GM variety. So, does this Does this indicate widespread acceptance? "The concerns of the general public must be addressed and they must not feel that scientists are playing God,'' says Thomas. He likens the resistance in various quarters to that felt by people when "innovations like electricity generation and in-vitro fertilisation were introduced.''
Dr Swarna Vepa, Project Leader, Food Security and Sustainable Agriculture at the M S Swaminathan Research Foundation says, "a blanket approval can certainly not be given for the development of GM crops.'' She says that it is extremely important to be aware of "who makes the technology available and at what price.'' Government institutions should monitor their development and be actively involved. "If seed varieties are available only through MNCs, the competitive edge will be lost,'' said Dr Vepa. Development of drought resistant varieties should be a thrust area, said Dr Vepa.
Monsanto, Pro Agro and Pioneer Dupont are the MNCs active in testing seed varieties. But protests have been staged at both the local and international level. "Farmers have shown a tendency to buy expensive seeds when there is the possibility of increased yield,'' said Dr. Thomas."Most varieties of GM crops show enhanced yield and this is an important consideration'', he said. Dr Thomas was emphatic that marginal farming should not be sustained in India.
European Leaders Urged to Take a Position on Gene Modification
Growing consumer concerns in Europe about gene-modified products have led to increasing pressures on EU leaders to clarify the risks and benefits of gene modification. Coming up with a coherent position will not be easy, as European governments are torn between the desire to foster scientific progress and the need to be aware of the concerns of consumers already rattled by mad cow disease and foot-and-mouth break-out.
Romano Prodi, president of the European Commission, warned that Europe would suffer economically by falling behind in the biotech race if the anti-GM lobby would be allowed to monopolize the debate. In a recent meeting of European agriculture ministers in the Belgian town Alden-Biesen.
John Manyo, a scientist working in Africa for the UN Food and Agriculture Organization, said the debate in wealthy European countries was holding back potential benefits for the developing world. "Developing countries should not, and must not, be denied the opportunities offered by biotechnology and genetic engineering,'' he said, adding that perceived food safety fears needed a scientific and not an emotional approach. Current projections indicated that the world could have 7.15 billion people by 2015, and food production would have to double to meet projected growth in demand, a difficult objective given nature's present limitations. "We are now nearer than ever before to critical thresholds in terms of availability of arable land, physiological yield ceilings and availability of water resources,'' he said. "Can biotechnology help to raise the yield ceiling...? Recent developments in agricultural biotechnology indicate that this is feasible.''
While the debate on genetically modified food goes on, the EU has instituted stricter labeling rules for biotech food. Under the proposed rules, companies would have to provide information on any GM crops used throughout the production chain. Some processed goods, such as vegetable oils, would still have to be labeled as "may contain GMOs'' even if the GMO is removed during production and cannot be detected in the final product.
Scientists Urge Mexico To Support Biotech Crops, Products
- Jonathan Eisenthal, Minnesota Corn Growers, 09/18/2001 http://www.mncorn.org/
A coalition of 3,200 scientists, including 16 Nobel laureates, has endorsed the safety and nutrition of biotech food crops, through an organization called the AgBioWorld Foundation. When Mexican President Vicente Fox arrived in Washington for a state visit on Sept. 5, AgBioWorld took the occasion to speak out against Mexico's refusal to allow newer biotech crops to be grown within its borders.
"It's ironic that the birthplace of corn - a crop that has become one of the most significant sources of food for the world - refuses to allow the use, either as seed for crops, or in products that people can eat, of the newer GM (genetically modified) crops," said Dr. C.S. Prakash, a scientist with Tuskegee University and the AgBioWorld Foundation.
Prakash said no direct response had come from Fox, whose most pressing concerns in dealing with the United States were immigration and adjusting NAFTA. But Prakash felt confident that Mexico's agriculture secretary, who accompanied Fox on the Washington trip, had received the message clearly, and that it would be communicated, hopefully to some affect, "among the movers and shakers in Mexico's agriculture," said Prakash.
Perhaps because of the importance of corn in Mexican culture and commerce, some of the foremost scientific researchers in biotech corn are working in Mexico, according to Prakash. Mexico is home to three of the world's most advanced corn research institutions, according to Prakash: the National Agricultural Research Program (INIFAP), the Center for Research and Advanced Studies (CINVESTAV) and the International Maize and Wheat Improvement Center (CIMMYT
Among many examples, one Mexican researcher has developed a strain of corn that produces high, safe yields, in spite of high aluminum toxicity in the soil in which it is grown. This technology could represent a huge breakthrough for Mexico and poor tropical nations where the problem of aluminum toxicity is prevalent, said Prakash. And yet, these products cannot be grown in Mexico because of its government's current policy on biotech crops.
"Corn underpins so much of the world's farming economy. And yet, in the past five years Mexico has not licensed any new biotech crop technologies. It's interesting to note that the very first biotech crop, the Flavorsaver Tomato, was first grown in Mexico in the mid 1990s. At the same time it was grown in California, it was grown in Mexico because of the late growing season. That tomato was marketed to Great Britain. It was clearly labeled as a genetically modified food in Britain, and yet it flew off the shelves."
Subsequent scare campaigns have affected the sales of such products, and Prakash denounced these tactics, from groups like Greenpeace. These campaigns ignore all the scientific studies, which underscore the safety and benefits of biotech crops. Prakash denounced such tactics in his letter to Fox. He recalled that two years ago Greenpeace actually blocked a shipment of American biotech corn from entering Mexico, and those who suffered were the subsistence farmers and the hungry and malnourished people who could have used that high quality, nutritive food source.
"Our group is a coalition of scientists who want to make sure that agriculture and biotechnology be addressed as scientific questions. Food safety and environmental concerns are also scientific concerns. The emotional element that some groups have used in order to scare the public has done a great disservice, especially to countries where there is a lot of poverty and malnutrition - they just cannot afford to overlook the benefits of GM crops. When it comes to food safety and nutrition, the concerns are not limited to GM crops, but we must extend scientific research to all foods that are grown."
On Patagonia and DNA Uptake by Humans
- Martina McGloughlin points out the contradictions
(Posted by Rick Roush to an Activist Newsgroup)
I was wondering if Patagonia outdoor clothing and equipment is as popular and beloved of greenies (elsewhere) as in the US. The reason that I am asking is that here the company appeals to their customers by taking every opportunity to knock GM technology as anti-environmental (for example www.patagonia.com/enviro/reports/euro_ge.shtml) and yet the really ironic part is that while spewing forth this invective Patagonia uses polylactide produced by GE organisms as the main wicking component of their clothes, especially the ever popular fleeces!! If they did not use this option their alternative source of polymer feedstocks are fossil fuels!!
Just thought that you might like another ironic twist to the story. There are of course many instances of "foreign" DNA being inserted into the human genome. The sources are invariably from infectious agents the vast majority of sequences being from RNA viruses who undergo "illegitimate recombination" during replication via reverse transcription. Almost all are neutral events providing no selective disadvantage to the host. However, there are exceptions. I myself am a recombinant organism having been the recipient of viral DNA from meningitis bug which subsequently initiated an autoimmune disease.
However, these insertions are all from organisms who for many millennia have been evolving mechanisms to get past our defenses and into the blood stream. If there were potential for DNA from plant and other sources to be incorporated following passage through the digestive tract then, over the many millions of years that we have been eating plants, you would have instances of for example plant virus DNA present in human sequences (for example every cell of a Cauliflower mosaic virus infected cabbage, the principal promoter used in transgenic plants, has about 10,000 viral particles with capabilities of insertion) and no such occurrence has been documented. So I think that it is safe to say that the probability of sequence insertion from eating plants is pretty much close to zero and if it does occur (for example short DNA fragments a few macromolecules in length may be transported from the gut lumen into the intestinal cells via endocytosis) then it always has done so as there are no inherent differences in
From: Bob Bowden
Sub: Inappropriate Comments
I hope we will refrain from any more responses like those of Andrew Appel to the recent tragic events in New York and Washington D.C. As we try to be communicators for the science of agricultural biotechnology, our credibility is always under scrutiny. To equate anti-GMO activists with the hijacker terrorists is unfair, inappropriate, and tasteless. Such things can only undermine our credibility as communicators.
Robert L. Bowden, Dept. of Plant Pathology, Kansas State University
From: Robert Vint
Subject: The Face of Terrorism
Dear Mr Apel,
I rather expected the far right and America's corporate lobbyists to tastelessly exploit the appalling crime in New York for their own ends (see your letter below) and to use it to advocate a return to McCarthyism. So is anyone who questions the right of the US Government to dominate the economies of foreign nations and its right to punish nations that refuse to buy its products now going to be labelled a terrorist? Are the farmers in India, Mexico, Indonesia, the Philippines and Brazil, who struggle to protect their rural economies from corporate control and GM crops, now to be equated with people like Mr bin Laden? Are the consumers in Sri Lanka, whose wish for a ban on GM foods was overturned by foreign corporate threats, to be seen as enemies of America? Are the African nations that have agreed laws to ban GM crops designed with 'hostile intent' to be labelled as murderers? And are all American citizens who campaign for global democracy and the sovereignty of elected governments now going to be accused
Most American citizens are amazed by (or still unaware of) the massive unpopularity of their government in developing nations that has resulted from decades of its bullying, arrogant and exploitative foreign policies. This unpopularity makes it possible for extremist groups to flourish in the Middle East and elsewhere. Your own statements perfectly exemplify the kind of blind arrogance that provoked the insanely brutal response of the suicide bombers.
Mr Apel, it is time for you and your cronies to repent.
- Robert Vint.
>From: Andrew Apel firstname.lastname@example.org>
>Subject: The Face of Terrorism
>With the recent attacks on workers in the World Trade
>Center and the Pentagon, attacks perpetrated by those who
>put political ideology above human life, we have an.........
From: Andrew Apel
Subject: Re: The Face of Terrorism
Dear Mr. Vint,
The growth of the global economy poses many challenges, and as you well know, any change has its opponents. Regardless, we must throughout guide ourselves with a moral compass that points to human welfare. History has chronicled the results of believing that there are ideals which supersede human happiness, or misery; and the proponents of such misguided ideals are justly vilified.
I do not believe you would applaud an attack on your person or your home as an acceptable form of expression, any more than you can find in my remarks some preference for McCarthyism. In an open culture, credible debate is more than welcome, it is part of cultural growth.
Mr. Vint, I ask you to join me in condemning the terrorism perpetrated with airplanes on New York and Washington. I invite you to join me in condemning the attacks of ELF and Masipag and Confederacion Paysanne and others on experimental crops and research facilities. I ask you to join me in condemning the thugs who inflicted immeasurable damage on the peaceful cities of Genoa, Gothenburg, Prague, Seattle and Quebec.
Finally, Mr. Vint, I invite you to join me in condemning all violence and destruction that masquerades as being part of a "public debate." On the other hand, perhaps you prefer to consider the firebombing of Dresden to have been an "artistic statement."
Value-Added Biotech Crops On Horizon
- David Scott, Associated Press 17 Sept 2001
It's something that perhaps few Americans think much about: Is there enough beta carotene, or Vitamin A, in my diet?
Yet to people in the Third World, it's a grave concern. Extra Vitamin A could be a key step toward preventing millions of children in developing nations from going blind or dying from such things as diarrhea and childhood measles. But supplements are an extra cost, and seeing that a nation of millions takes an extra pill with meals is nothing less than a logistical nightmare. And if asking, 'Is there a better way to deliver extra beta carotene?' is the first question, the second might well be, 'Could there be a better way than putting it into the food those millions depend on to survive?'
Those questions led to the development of "golden rice," a grain that scientists in Europe genetically engineered to contain extra beta carotene. Their work is visible in the very grain itself, as the extra Vitamin A gives it a golden hue. While the practical use of golden rice, and its cousin, golden mustard, are years from realization, the very development of the rice is a harbinger of what could arrive in farmers' fields in the next 100 years - plants that bring more to the table than previously advertised.
"Among other things, scientists are exploring whether it is possible to increase cancer-fighting ingredients in food ... to deliver vaccines in fruit and to rescue threatened species such as the American chestnut tree," said a report released this month by the Pew Initiative on Food and Biotechnology.
To this point, bioengineered crops are best known for there ability to fight weeds and pests. Some contain traits that allow the crop, but nothing else, to survive a mass-spraying of a viciously effective herbicide; others, a poison that's harmful to pests, but nothing else.
Perhaps the best example are the Roundup Ready plants developed at Monsanto Co. in St. Louis. These plants can survive applications of Roundup, the company's widely used pesticide. So popular is the concept and so valuable in its practice, that Roundup Ready soybeans account for 68 percent of those grown in the United States.
In all, seeds containing Monsanto biotechnology were planted on 103 million acres in 2000. But existing biotechnology possesses benefits seen only by the farmer; consumers at the grocery store can't tell the difference. (Much to the dismay of some critics, who feel the products should be labeled.) Golden rice is an early example of how biotechnology could be used to bring a direct benefit to those who aren't on the farm.
In St. Louis, products in Monsanto's pipeline include corn that is drought-tolerant, cold-tolerant and higher-yielding, along with high-oil canola and soybeans. The National Research Council's Board on Army Science and Technology released a report earlier this year that discussed the potential for bioengineered crops that can grow in days instead of weeks, have "bio-markers" to counter friendly fire, or include enzymes that make them more digestible.
"Biotechnology and biological materials have potential to greatly improve the logistical support of the Army," said Michael Ladisch, a Purdue University professor who chaired the NRC committee that produced the report. "Genetically engineered foods have a role to play, not only through functional foods, but also through foods that can grow quickly."
Like the researchers in Switzerland, who developed golden rice, scientists in England are working on fruit with a protein that protects against tooth decay. The Pew Initiative report, which looked at the future of biotech crops in detail, even talks about the prospect of plants that can detoxify soils.
"Many of these products are likely to generate significant public debate over their relative risks and benefits," said Mike Rodemeyer, the Pew Initiative's executive director. "In addition, the broad scope of the research ... raises important questions, including whether the regulatory system will be ready for the next generation of biotechnology products."
Certainly, there are plenty of critics of the use of biotechnology in crops, especially in Europe, where regulators have placed a moratorium on approving any new genetically modified crops. And the debate over the safety of biotech crops in the United States reached a fervor last year, when genetically modified corn that hasn't been approved for human consumption was found in taco shells. The incident spawned nationwide recalls of food products and focused attention on efforts to place labels on foods produced with biotech crops. Still, farmers continue to back the science, planting 18 percent more acreage with biotech crops over last year.
The Biotech Boom: Creating Frankenforests
- Stasia Bochnowski, Red Herring September 14, 2001 http://www.redherring.com/
Manipulating tree genes is nothing new. But instead of using the slow and inaccurate process of conventional breeding, which mixes all of the genes from two trees, scientists can now target individual genes and even insert genes from animals in order to create trees with extraordinary characteristics. Research is focused on developing trees with faster growth rates, lower levels of lignin (a polymer that must be removed to make paper and pulp), and resistance to pests and diseases.
Genetic engineering of trees could boost productivity in the more than $600 billion worldwide paper-and-forest-products industry, a lucrative opportunity for researchers who patent and license the technology. By growing low-lignin trees, the U.S. paper industry could cut the cost of producing pulp by between $1 billion and $3 billion per year, according to Vincent Chiang, director of the plant biotechnology research center at Michigan Technological University.
Still, forestry companies recognize the opportunity, and two joint ventures have sprung up: ArborGen, a research consortium composed of Genesis, International Paper (NYSE: IP), Rubicon, and Westvaco (NYSE: W), representing the mainstream multinational lumber interests; and GenFor, a corporation owned by Cellfor and Biogenetics, two biotech startups.
Those pushing the biotech approach say genetic engineering can decrease forestry's effect on the environment by shrinking the footprint of plantations and lowering the content of lignin (which requires toxic chemicals to remove).
NEW-GROWTH ISSUES: Environmentalists have long been foes of the forestry industry, arguing that harvesting trees disrupts habitats and hurts the environment. So it's no surprise they have reservations about genetically engineering forests. The World Wildlife Fund fears that transgenic trees will be so hardy that they will create resistant strains of pests or destroy diverse habitats by taking over wild forests. Since seeds and pollen can travel hundreds of miles on the wind, some worry that hardy transgenic trees could supplant wild forests. To prevent this, researchers are working to make their trees sterile.
There's no guarantee these trees will remain sterile for their entire life spans (up to 300 years), says an official from the Canadian Forest Service, which is also involved in genetic engineering research. However, the trees would be genetically engineered to grow quickly, so they could be harvested before they are old enough to reproduce, according to Mr. Chiang.
Genetically engineered trees will not be commercialized for at least five years. But the Forest Stewardship Council (FSC), an international nonprofit organization that certifies wood harvested using sustainable, environmentally sound forestry practices, has already said it will not certify wood from genetically engineered trees. Though it has been estimated that FSC-certified products represent only 1 percent of the market in the United States and 5 percent in Europe, "the market is literally exploding," with 50 to 100 companies getting certified each month, says Barry Sims, senior forester of ForestWorld, a forestry consultancy. Demand may be increasing: the Home Depot (NYSE: HD), a large U.S. retailer, has said it will sell as much FSC-certified wood as possible, and its competitors have followed suit.
Many of the large wood and paper companies hope genetic engineering can boost productivity in the capital-intensive industry and believe the FSC could warm to genetic engineering by the time the trees are commercialized. "The FSC has been known to reconsider its policies over time," says Dawn Parks, manager of public and government affairs at ArborGen.
Indonesia to Expand Bt Cotton
Indonesia's agriculture minister announced yesterday that the government would proceed with planting genetically modified (GM) cotton despite strong opposition. The government is planning to develop 20,000 hectares (49,400 acres) of GM cotton plants in South Sulawesi in cooperation with U.S. biotechnology giant Monsanto Co. The deal was delayed in September last year owing to strong protests from environmental activists.
The government's pilot project in 4,363 hectares of cotton fields showed the productivity of the transgenic cotton was 2.2 tons per hectare, far higher than the 1.4 tons a hectare for the Kanesia cotton commonly planted in Indonesia. Indonesia would need to develop high-productivity cotton buds, which contain the fibers, to meet domestic demand forecast at 1.5 million tons of buds this year. Existing output meets less than one percent of total annual demand for buds, used mainly in the textile industry. Indonesia imported 500,000 tons of cotton every year.
Seed v Seed: Mass-producing Some Drugs May Require Green Fingers
- The Economist, Sep 6th 2001 http://www.economist.com/displaystory.cfm?story_id=770963
Wait till the Greens hear about this — let alone the Catholic Church. It was bad enough when evil boffins were genetically modifying plants to make them more nutritious, or more resistant to pesticides. Now Epicyte, a company based in San Diego, is growing crops meant to kill human sperm.
Secretory antibodies are proteins of the immune system that coat the wet, warm parts of the body to protect them from attack. Both the fight against sexually transmitted diseases, such as herpes, and efforts to stop pregnancy would be helped if women's reproductive tracts were supplemented with appropriate antibodies. Epicyte has now produced anti-sperm and anti-herpes antibodies in gel form. But such products have to be made in bulk to be cost-effective.
Usually, mass-producing antibodies involves building an expensive fermentation plant in which bacteria designed to make the compounds are grown in large quantities. Epicyte decided that plants of a different kind could do the job more cheaply: green ones. Despite outward appearances, genetically modified maize plants seem perfectly able to make human antibodies. “Plants”, according to Mitch Hein, the chief executive of Epicyte, “are very much more like humans in their cellular structures than people realise.”
Maize seeds are also an ideal storage place for proteins, as they offer a dry, stable environment with very little of the water that might degrade fragile antibodies. Once the seeds have been harvested, the antibodies can be extracted and turned into medicines.
The beauty of Epicyte's antibody “factory” is the ease with which its capacity can be expanded. When the company needs to produce more antibodies or to broaden its range of products, it can avoid the capital costs of building another fermentation unit by simply planting another field. Assuming it is not destroyed by protesters, of course.
Of Maize and Men: Is The Endorsement of GM Crops Science or Politics?
- Stefan Flothmann and Jan van Aken;
Greenpeace, Germany ; EMBO Reports vol. 2 no. 8 pp 644-647 2001
‘Outside the agricultural environment these genes are considered to be of no advantage, and thus, such hybrids will rapidly disappear once the crop is removed from the field’ (Trewavas and Leaver, 2001).
‘Regulatory agencies all over the world have permitted field trials for over 20 years now, so these things are there in the environment. If you’re saying you can’t have them, you’re saying normal biological processes can’t take place.’ (Simon Barber of the biotech association Europabio, European Voice, 2001).
In the June 2001 issue of EMBO reports, Anthony Trewavas and Christopher Leaver asked whether opposition to GM crops is science or politics. For Greenpeace, as a political pressure group, the answer is clear: it is politics. For scientists such as Trewavas and Leaver, however, the question ought to be ‘Is endorsement of GM crops science or politics?’ The authors raise no doubt that, for them, the answer too is politics. By arguing that 40 000 people are dying every day from malnutrition and leaving the reader with the impression that overcautiousness would be responsible for further suffering, they clearly make a political argument rather than a scientific approach to assess the safety of GM crops. Indeed, the authors fail to quote literature showing that sustainable agriculture projects in the Southern Hemisphere (Pretty and Hine, 2001) promise ways to increase food production whilst decreasing environmental impact and agro-industrial profits. By acknowledging that GM crops will not feed the world or elimi
The political arguments opposing GM crops are manifold and range from corporate control versus food sovereignty, the freedom of choice when even organically grown food is threatened to be contaminated, the transparency and democratic level of decision making in genetic engineering politics and the preference of locally adapted developments over global ‘one size fits all’ solutions. But we will focus on some scientific aspects of the discussion. We believe that one aspect of sound science is an assessment of all available data. In their article, Trewavas and Leaver avoid mentioning scientific publications that question the safety of GM crops. Here, we will present some additional research in order to give a more complete overview of recent studies in biosafety research.
Genetic engineering is a completely different technique from traditional breeding, and as such, this could make transgenic crops a special threat to the environment. First, transgenic plants contain genes and traits that are completely new to the species and its environmental context. While traditional breeding can transfer genes only among related varieties or closely related species, genetic engineering allows for a movement of genes to radically different species. Conventional breeding is not able to cross a bacterium with a plant and therefore there has never been a crop with the Bacillus thuringiensis (Bt) toxin gene to defend itself against predatory insects. Trewavas and Leaver are right in pointing out that the genes introduced through GM are not qualitatively different from those genes introduced by conventional breeding—insect resistance is indeed not new to maize. But they fail to realise that the very nature of the transgene may have important ecological repercussions. A conventional maize insec
Secondly, the process of genetic engineering is neither targeted nor precise, but rather a crude intervention. As foreign genes are integrated with the plant genome in a random fashion, it is merely a matter of luck if the transgene is expressed as desired without inducing other changes in the plant’s physiology or metabolism. Several mechanisms are known to influence the specific outcome of such a gene transfer and these cannot be anticipated. Also, foreign genes are regulated by their own promoters, thus bypassing the tight control system of the cell. Most scientists would agree that our understanding of the natural processes of recombination and the regulatory processes underlying conventional breeding techniques is still far from complete. It is therefore daring to assume that the particle gun is more accurate.
These two fundamental differences between conventional plant breeding and genetic engineering can have unforeseen consequences when transgenic plants are released into the environment. An array of risk scenarios has been discussed during the past decade. Some are rather hypothetical, while others have recently been shown to be closer to reality. The following three examples will highlight possible detrimental effects of transgenic plants on the environment.
Commercial enterprises have inserted herbicide, insect and virus resistance genes into important crops such as soybean, maize, rapeseed and wheat to confer a selective advantage to the plant in agricultural settings. These three traits provide for nearly 100% of all transgenic crops planted in 2000 (ISAAA, 2000). One likely threat that may result from resistance genes is the inadvertent and unwanted creation of plants with superior survival abilities against natural predators and human intervention. Often dubbed ‘superweeds’ in the public debate, such plants have an evolutionary advantage that would allow them to invade and/or take over entire ecosystems and drive out other species. Either the cultivated crop or sexually compatible relatives receiving the transgene could acquire (additional) weedy characteristics. The risk is greatest in areas where the crop plant originated because compatible plants—local varieties and landraces of the crop or wild species—will be abundant and facilitate the transfer of th
The major pathway of gene escape is via pollen transfer. Several studies have tried to determine the frequencies and distances of gene flow for several crop plants. The only consistent result of the experiments was that they are not consistent. In rapeseed, for example, outcrossing frequencies varied from 0.1% for a distance of 1 m (Pauk et al., 1995) to 1.2% at a distance of 1.5 km (Timmons et al., 1995). Indeed, a wealth of data has been produced on gene transfer during the past decade (Klinger et al., 1992; Manasse, 1992; Kareiva, 1994; Arriola and Ellstrand, 1996; Llewellyn and Fitt, 1996; Hokanson et al., 1997.) These studies measured actual pollination success and not—as suggested by Trewavas and Leaver—physical pollen distribution. It has been shown with a variety of different crops that experimental design and environmental parameters strongly influence outcrossing rates. Most scientists in this field therefore acknowledge that there is no ‘safe’ distance around a field of GM crops to prevent gene t
For Central Europe, rapeseed and beet are of specific concern. Various forms of rapeseed grow in Europe, some of them are cultivated as crops, while others are regarded as ‘weeds’. Spontaneous hybridisation between cultivated rapeseed and four wild-type relatives (Brassica rapa, B. juncea, B. adpressa and Raphanus raphanistra) has been reported (Eber et al., 1994; Mikkelsen et al., 1996), while introgression of a B. napus transgene into a weedy B. campestris population was also observed (Mikkelsen et al., 1996). Rapeseed is a persistent volunteer as the seed heads shatter easily and the seeds can remain dormant for a long period.
Herbicide-tolerant plants could also accumulate various genes to become multi-resistant plants which will be as difficult to control as multi-resistant bacteria. The first rapeseed plants with a resistance to three herbicides—Monsanto’s Roundup, Cyanamid’s Pursuit and Aventis’ Liberty—were identified in 1999 on a field in Alberta, Canada. The Royal Society of Canada warns that ‘herbicide-resistant volunteer canola plants are beginning to develop into a major weed problem in some parts of the prairie provinces of Canada.’ Indeed, some scientists predict that volunteer canola could become one of Canada’s most serious weed problems because of the large areas of the prairie provinces devoted to this crop (Canadian Royal Society Expert Panel Report, 2001).
Experimental data on the potential invasiveness of transgenic plants are still limited. Trewavas and Leaver pointed out one study that suggested no additional invasiveness of transgenic plants in comparison with conventional varieties. However, another study provided preliminary evidence that insect resistance indeed confers a selective advantage under environmental conditions as measured by an increased reproductive success of Bt rapeseed plants compared with non-transgenic varieties (Stewart, 1997).
Another potentially detrimental effect could come through the use of insect-resistance genes in GM crops. Bt toxin genes are currently the second most important commercial trait of transgenic crops and they pose a special threat to the insect population. A series of studies have now disproved the presumption that Bt crops harm only target pests. Lacewings—important beneficial insects—fed with corn borers raised on Bt maize suffered from increased mortality (Hilbeck et al., 1998), and monarch butterflies fed on milkweed dusted with Bt pollen were severely affected in growth and development (Losey et al., 1999). Other non-target species affected in controlled experiments include Coleomegilla maculata (Riddick and Barbosa, 1998), while Birch et al. (1999) showed the effect of snowdrop lectin on ladybirds. Data provided by the industry and published by the US-EPA also demonstrated a side-effect on collembola (EPA). It is likely that effects on other insect species would be revealed if the necessary experiments
But Trewavas and Leaver dismiss those non-target studies on the grounds that they were laboratory studies and worst case scenarios: ‘just as an airline crash is the worst case scenario for flying’. Apart from the fact that planes actually do crash once in a while, the Losey study has been recently confirmed in field experiments, mimicking real world scenarios (Hansen and Obrycki, 2000). Furthermore, indirect effects were also reported. A field study of Bt potatoes showed a significant decline of a specialised ground beetle predator (Lebia grandis) after its primary prey species, the Colorado potato beetle, was eliminated. In the same study, the authors reported a significant increase in the number of leafhopper (Empoasca fabae) adults and nymphs in both the pure Bt potato fields and the mixed fields consisting of both GM and conventional potatoes (Riddick et al., 1998). The findings illustrate that the decline of specialised predators can lead to the emergence of secondary pests exploiting the now abundant
It has been argued that the use of chemical insecticides would have a far more detrimental effect on the fauna. Apart from the fact that the maize corn borer was hardly ever controlled with synthetic insecticides, transgenic crops produce and expose the Bt toxin throughout the growing season in large quantities. Thus, the exposure of the insecticide to the local insect population is longer than when synthetic insecticides are used. Through the decrease of beneficial insects or indirect effects on predators higher up in the food chain, Bt crops can therefore affect whole ecosystems.
Furthermore, pests of all kinds have so far been able to withstand any human attempt to control them. By planting Bt crops and thus increasing the exposure of the pests to the toxin, the probability that insect species develop resistance against the toxin increases. Bt toxin is an ecologically-friendly pesticide and has been used with much success in organic agriculture. But Bt crops could soon render it useless, as the additional exposure may facilitate the rise and spread of resistance among insect pests. Since the traditional Bt spray is applied only a few times during a growing season and degrades rapidly within hours, the selective pressure to develop resistance is very low. Bt plants that expose insects to the toxin throughout the growing season are more likely to trigger resistance of the insect species.
It is hard to understand why proponents of GM crops disqualify risk assessment studies because they are laboratory studies. In fact, risk assessment of hazardous chemicals is based in large part on the concept of acute toxicity—the administration of high quantities of a substance to measure short-time effects and lethal doses. Carcinogenicity is not tested by real world scenarios—the administration of low doses over several decades—but for obvious reasons by short-term experiments using higher concentrations of the substances. However flawed this concept might be, it has helped to identify an array of hazardous substances, and no one would argue for the safety of benzene or other carcinogens on the grounds that their hazardous nature was only tested in worst case studies.
Herbicide-tolerance genes can have ecologically detrimental effects too. Indeed, any ecologically-friendly development in agriculture should aim at reducing—preferably to zero—the application of synthetic herbicides. As the introduction of herbicide-tolerant crops has raised the question of whether they lead to an increase or a reduction of herbicide use, a wealth of data has been produced to support either view. Here, Trewavas and Leaver quote a study by Heimlich et al. (2000), published by the US Department of Agriculture, where a variety of data are presented, including an increase of 2.4 million pounds of active ingredients due to the adoption of herbicide-tolerant corn. However, the key problems in assessing the actual use of herbicides are the large differences between geographic regions, tillage systems and years. The most comprehensive approach to address these differences has been published recently by Benbrook (2001). His article provides a comprehensive review of the methodology used to assess th
In addition to these concrete effects—creation of superweeds, non-target effects or increased herbicide use—unintended effects can cause unknown and unforeseeable changes in a plant’s metabolism. Examples include the splitting of the stems and stunted growth of herbicide-tolerant soybeans under high temperature conditions, or the change in wood colour in transgenic aspen with an altered lignin metabolism (Lapierre et al., 1999). Transgenic plants exhibiting obvious deviations are selected against prior to commercialisation, but many unintended effects will go unnoticed during the preliminary trials and may lead to detrimental effects that can neither be foreseen nor assessed before a release into the environment.
Of course, the specific risk of a transgenic plant differs, depending on the plant species, the nature of the transgene and the environmental context. Bt maize grown in Germany has little chance of outcrossing and becoming a ‘superweed‘, but it has a large likelihood of harming indigenous insect species. In fact, current risk assessment procedures cannot estimate the true potential risk of a given transgenic plant. First, it is impossible to predict the unintended effects, as described above. Secondly, common risk assessment procedures, having been developed for toxic chemicals or nuclear power plants, are not applicable to transgenic organisms. Such procedures are based on a quantitative approach and an estimation of exposure rates. Transgenic plants, however, are self-replicating organisms that cannot be quantified for risk assessment purposes, because a single organism escaping from the target area can generate millions of new ones. In light of this inherent feature, and considering the manifold unknown
The tremendous difficulties in controlling transgenic plants are highlighted by the recent StarLink scandal in the USA. StarLink is a Bt maize line that was registered only for animal feed use in the USA. However, in summer 2000, the first food products contaminated with StarLink maize appeared on the shelves in several countries. Even the 2001 seed stocks from several seed companies were found to be contaminated with StarLink. Aventis meanwhile acknowledges that the Cry9 gene of StarLink can no longer be recalled. This example emphasises that a commercial release of a transgenic plant will ultimately lead to a global spread of the transgene in food, feed and agriculture. StarLink must also be taken as a huge warning sign against the release of transgenic plants that produce bioactive compounds, such as pharmaceuticals. It would be a disaster if a potent heart drug or a blood-coagulating agent ends up in our cereals, as happened with StarLink maize.
Greenpeace therefore believes that transgenic crops pose some unique threats to the environment and human health, and calls for a ban on all releases of living GM organisms into the environment. There is no technical development without risks, and Greenpeace emphatically supports new technologies in many areas—which obviously all bear risks. As human beings, we are all subject to mistakes, so any new technology must allow for mistakes too. But the decision to take a risk must be based on the availability of strategies to avert major damage if something goes wrong.
The release of genetically engineered plants into the environment does not allow for mistakes. If such a plant turns out to have a disastrous effect, either on the environment or on human health, we have no measures at hand to deal with the problem. Once released into the environment, transgenic plants can never be recalled and they cannot be contained or confined. In the light of sustainable alternatives in agriculture, in the developed and developing world, should we really take this risk when there is no need?
For REFERENCES, Please See Original website at http://www.embo-reports.oupjournals.org/cgi/content/full/2/8/644