What is wrong with Genetic Engineering?
GE is a test tube science and is prematurely applied in food production. A gene studied in a test tube can only tell what this gene does and how it behaves in that particular test tube. It can not tell us what its role, and behavior are in the organism it came from or what it might do if we place it into a completely different species.
Would that change the quality of food produced by GE technology?
We also know a very little about what a gene / or for that matter any of its DNA sequence / might trigger or interrupt depending on where it got inserted into the host / plant or animal /.
There are open questions around positional effects. And what about gene silencing and gene instability.
Until we have an answer to all these questions, GE should be kept to the test tubes.
While it is commonly agreed amongst the scientific community that gene escape is a likely event, its impact is debatable. One major fear is the possibility that the newly introduced gene will confer a selective advantage and will thus enable the plant to out-compete and overrun other natural vegetation. The risk is greatest when a wild relative of a GE plant is already considered a weed. Should this weed acquire – via pollen transfer – new genetic material conferring a selective advantage, it might wreak havoc in both agriculture and natural habitats. Genetically engineered 'super-crops' could transfer their foreign genes to other plants and in time, could totally displace other varieties and accelerate the disappearance of native cultivars on which organic agriculture relies. The impacts are unknown and irreversible.
Many crop species – such as oilseed rape, potato, tomato, or beans – have close relatives that are already considered major weeds. It is obvious that many of the traits favoured by genetic engineers would confer a fitness advantage, especially resistance to pest and diseases or tolerance to drought and salinity. Researchers at the University of North Carolina found recently that insecticidal oilseed rape containing a bacterial gene (Bt) had a higher fitness than the conventional oilseed rape. The GE plants produced significantly more seeds than their natural counterparts. The researchers concluded that ‘insecticidal oilseed rape could pose an ecological risk upon environmental release. Since oilseed rape is already a minor weed in certain areas, the ability to strongly resist defoliation may allow it to selectively persist to a greater extent by replacing non-transgenic naturalised populations.’
If GMOs survive and flourish, they could displace natural wild species and those plants and animals that depend on them. The drive to create 'super-crops' designed to protect themselves against their main enemies, such as insects and disease, could result in their proliferation at the expense of native plants. The biodiversity of ecosystems located near fields of 'super-crops' could be threatened. In time, the engineered plants could entirely replace the native flora and threaten the survival of the wildlife that depend on them.
History has already taught us that introducing non-native species into new habitats can have catastrophic results. Predicting all the long-term impacts of exotics has proven to be impossible. A famous example is the introduction of Nile perch into Lake Victoria in the 1960s which has decimated the native fish species, with over 200 species disappearing. As a further side effect, deforestation and erosion of the shoreline has occurred because Nile perch - unlike the native fish - cannot be sun dried and have to be smoked on wood fires.
The dangers of releasing GMOs could be even greater than releases of radioactivity and toxic chemicals into the environment. Unlike the products of nuclear and chemical pollution, GMOs can reproduce. Once released into the environment, they can multiply, spread, mutate and transfer their genetic material to other, often related, organisms. Once released, GMOs cannot be removed.
Insect resistance is one of the key traits currently engineered in the laboratories of the big seed companies. Through genetic engineering, toxins are introduced into crop plants that kill insects that thrive on the plants. The most often used toxins are the so-called Bt toxins, from the soil bacterium Bacillus thuringiensis, which includes a whole array of different Bt toxins, with different toxic properties. The toxins are selective in that they do not ill any insect, but only a specific selection of some insects. There are Bt toxins that are said to be specific for flies, others for butterflies or beetles. For decades, bacterial formulations have been used in agriculture - especially in organic agriculture - to fight insect pests.
A series of scientific studies have now disproved the presumption that the Bt toxin in transgenic crops has the same favourable characteristics as the Bt toxin in its natural state. There is now awareness among scientists that the Bt toxin in transgenic crops – as opposed to the Bt toxin in its natural form in bacteria - can harm species higher up the food chain, and may become accumulated in the environment.
In its interaction with bacteria, the natural Bt toxin will occur in a crystalline inactive state. However, in transgenic Bt crops, such as Pioneer’s maize, the toxin will occur as a soluble pre-activated plant protein, which is produced throughout the entire plant life. Genetically engineered insect resistance crops may therefore prove harmful to many non-target species, and may further disturb ecological balance:
These studies raise major concerns about the impacts of transgenic Bt crops on non-target species As a result, species further up the food chain, such as birds, could face reduced food supplies.
In addition, the threat to predatory species also threatens to undermine modern pest management. The preservation of predatory fauna associated with crop pests is one of the most important tools for modern pest management. For example, the green lacewing and the ladybird are the most important beneficial predatory species to control pest insects.
Bacillus thuringiensis (Bt) is a soil bacterium that produces a toxin that is highly valued by organic farmers. These bacteria have been sprayed on crops for more than 50 years as a safe form of biological pest control. Bt targets particular species of insect, such as caterpillars, and the sprays are especially valuable to organic farmers in instances where there is a serious pest infestation.
Crop plants, such as maize, have now been engineered with the gene for the Bt toxin to give then an in-built insecticide. These transgenic ‘insect-resistant’ crops were grown on 7.7 million hectares worldwide in 1998. In marked contrast to the occasional application of the Bt toxin in organic farming, the transgenic Bt toxin is produced in the plants all the time they are growing. This means that insects are continually exposed to the toxin, and are therefore under constant pressure to develop resistance.
There is overwhelming scientific data showing that resistance to Bt toxin will develop with the use of GE Bt crops. This is a most serious concern as it may jeopardise the further use of natural Bt formulation in environmentally friendly farming systems. Bt resistance has already been noticed among some insect populations, and the US Environmental Protection Agency (EPA) has predicted that most target insects could be resistant to Bt within 3-5 years.
Insect resistance to natural insecticides, such as the Bacillus thuringiensis (Bt) toxin, is a major problem for organic farming. Organic farmers have been using natural preparations of Bt toxin as an environmentally friendly pest control tool for decades. For example, in the USA, potato farmers have been using the natural Bt formulation to control the Colorado potato beetle (CPB). In some areas where there was widespread resistance of the CPB to synthetic insecticides, the natural Bt sprays saved the potato industry.
Natural preparations of Bt toxin are composed of natural crystals of toxin contained in spores. These are simply sprayed on the crop but then are rapidly inactivated by sunlight and other environmental factors. The crystals have a half-life of around 2.7 days and although spores can remain viable in soil for two years, they are inactivated within a few days on leaves. In contrast, the Bt toxin from genetically modified crops is produced on an on-going basis in the crop and herbivores are therefore likely to be exposed to it for long periods.
In the USA, all field populations of the Colorado potato beetle (CPB) are still susceptible to Bt toxins. However, a Bt resistant CPB has been detected in a laboratory experiment. This selected CPB strain could survive for two generations on the transgenic Bt plants. Moreover, the development of resistance of an insect to one Bt toxin often leads to cross-resistance with other Bt toxins. For example, insects selected for resistance to CryIA(c) Bt toxin also developed resistance to CryIA(a), CryIA(b), CryIB, CryIC, and CryIIA Bt toxins.
“The ability to clear fields of all weeds using powerful herbicides which can be sprayed onto GE herbicide-resistant crops will result in farmlands devoid of wildlife and spell disaster for millions of already declining birds and plants.”
-- Graham Wynne, Chief Executive of the UK’s Royal Society for the Protection of Birds
Until now, most of the research by the biotech industry has focused on making crops resistant or tolerant to their own ‘broad spectrum’ herbicides. These herbicides are non-selective, they kill every green plant. This means that a field can be sprayed with chemicals and nearly all plants will die except the resistant crop. Of the 27.8 million hectares of GE crops planted worldwide in 1998, 71% were herbicide-resistant. Herbicides themselves are known environmental polluters found in food, soil and water. By developing herbicide-tolerant plants, it is clear that the intention is to use them in agricultural systems that include the use of herbicides.
Last year, a study on herbicide use in herbicide resistant plants revealed that US-farmers growing RoundupReady soybeans used 2 to 5 times more herbicide measured in pounds applied per acre, compared to the other popular weed management systems used on most soybean fields not planted to RR varieties in 1998. A grower survey in Missouri revealed that most if not all fields planted to RR soybeans received at least one herbicide application.
Margaret Mellon, from the Union of concerned Scientists believes that many farmers may be turning towards GE herbicide-resistant crops because they are becoming desperate for new weed control tools. Farmers growing monocultures of maize and soybeans are facing serious weed problems. Many weeds have become resistant to chemical herbicides and multiple applications of herbicide are no longer effective as new weeds emerge.
Symptoms of acute poisoning in humans following ingestion of Roundup, include gastro-intestinal pain, swelling of the lungs, pneumonia and destruction of red blood cells. Eye and skin irritation has been reported by workers mixing, loading and applying glyphosate, the chemical name for Roundup. Between 1966 and 1980, well before Roundup came to widely used, the US Environmental Protection Agency’s Pesticide Incident Monitoring System had 109 reports of health effects, including nausea, diarrhoea and fever, associated with exposure to glyphosate.
Roundup is 100 times more toxic to fish than to people, toxic to earthworms, soil bacteria and beneficial fungi. Scientists have measured a number of direct physiological effects of Roundup in fish and other wildlife, in addition to secondary effects attributable to defoliation of forests. Breakdown of glyphosate into N-nitrosoglyphosate and other related compounds has heightened concerns about possible carcinogenicity of Roundup products.
A 1993 study at the University of California at Berkeley’s School of Public Health found glyphosate was the most common cause of pesticide-related illness among landscape maintenance workers in California, and the third most common cause among agricultural workers.
A 1996 review of the scientific literature by members of the Vermont Citizens’ Forest Roundtable revealed updated evidence of lung damage, heart palpitations, nausea, reproductive problems, chromosome aberrations and numerous other effects of exposure to Roundup herbicide.
But, herbicide tolerant plants could themselves pose environmental risks:
Clearly, the solution to weed control lies not in GE technologies, but in restoring more sustainable farming practices, such as crop rotation and smaller plots, which reduce the weed problem in the first place.
To assess the food safety of genetically engineered foodstuffs (GEFs), consumer experts are concerned about four major areas:
Consumers in Western Europe first became aware of GE food in 1996, when Monsanto’s herbicide-tolerant soybeans grown in the US started to arrive in Europe. Over 40% of the US soybean harvest is exported and the GE soybeans are mixed in with the conventional harvest. The American Soybean Association rejected calls to segregate the GE soybeans on the basis that they are ‘substantially equivalent’ to ordinary soybeans.
The concept of ‘substantial equivalence’ has been at the root of the international safety assessment and testing of GE food. According to this principle, selected chemical characteristics are compared between a GE product and any variety within the same species. If the two are grossly similar, and if the introduced GE traits are not thought to be toxic and allergenic, the GE product does not need to be rigorously tested on the assumption that it is no more dangerous than the non-GE equivalent.
The use of ‘substantial equivalence’ as a basis for risk assessment is seriously flawed, and cannot be depended on as a criterion for food safety. It focuses on risks that can be anticipated on the basis of known characteristics, but ignores unintended effects, known as ‘pleiotropic’ effects, which may arise. Genetically engineered food may, for example, contain unexpected new molecules that could be toxic or cause allergic reactions. A product could not only be ‘substantially equivalent’, but even identical to its traditionally produced counterpart in all respects bar the presence of a single harmful compound. It has also been argued that substantial equivalence acts against rigorous scientific inquiry because it prevents testing of the assumption that GE does not cause changes that are more dangerous than traditional breeding.
A recent lawsuit against the US Food and Drug Administration (FDA) has forced the release of government documents showing that FDA scientists had expressed grave doubts about the safety of GM foods, even as the agency was publicly declaring such foods ‘substantially equivalent’ to traditional crops. It seems clear from these documents that the scientific integrity of the US regulatory system has been compromised for political purposes, to provide a ‘fast track’ for the rapid, large-scale introduction of GM foods. Internal memos make it abundantly clear that FDA’s own scientists believe pleiotropic effects will occur when new genes are inserted into food crops. Commenting on the FDA’s proposed biotech regulations in early 1992, Louis Pribyl, an FDA microbiologist wrote 6 March 1992: “It reads very pro-industry…This is industry’s pet idea, namely that there are no unintended effects that will raise the FDA’s level of concern. But time and time again, there is no data to backup their contention, while the scientific literature does contain many examples of naturally occurring pleiotropic effects. When the introduction of genes into [a] plant’s genome randomly occurs, as is the case with the current [genetic modification] technology (but not traditional breeding), it seems apparent that many pleiotropic effects will occur”.
Instead of heeding the concerns of its scientific staff, FDA issued GE food rules that assume no pleiotropic effects will occur, therefore no safety testing is required. All GE foods are assumed to be safe.
The example of Tryptophan /100/
Food supplements, such as amino acids, are often manufactured by fermentative processes, in which large quantities of bacteria are grown in vats, and the food supplement is extracted from the bacteria and purified. One amino acid, tryptophan has been produced in this way for many years. In the late 1980's the Japanese company Showa Denko K.K. decided to use genetic engineering to accelerate and increase the efficiency of tryptophan production. They genetically engineered bacteria and altered the cellular metabolism substantially, leading to greatly increased production of tryptophan. These genetically engineered bacteria were immediately used in commercial production of tryptophan, and the product placed on the market in the USA in 1988.
Showa Denko was allowed to sell the tryptophan produced in genetically engineered bacteria without safety testing because they had been selling tryptophan produced in non-genetically engineered bacteria for years without ill effects. It was considered that the method of production (whether via natural or genetically engineered bacteria) was immaterial. In effect they considered it substantially equivalent to the tryptophan that had been sold for many years.
This product was placed on the market, and within a few months it caused the deaths of 37 people and caused 1500 more to be permanently disabled. It took months to discover that the poisoning was due to toxin present in the tryptophan produced using Showa Denko's genetically engineered bacteria. The disease caused by this toxic product was called eosinophilia myalgia syndrome or EMS.
It was later shown that the tryptophan produced in genetically engineered bacteria contained one or more highly toxic contaminants. The most prominent of these, called EBT, was identified as a dimerization product of tryptophan. It comprised less than 0.1% of the total weight of the product, yet that was enough to kill people. This compound was probably generated when the concentration of tryptophan within the bacteria reached such high levels that tryptophan molecules began to react with each other. Thus, it appears that genetic manipulations led to increased tryptophan biosynthesis, which led to increased cellular levels of tryptophan. At these high levels, these compounds reacted with themselves, generating a deadly toxin. Being chemically quite similar to tryptophan, this toxin was not easily separated from tryptophan, and contaminated the final commercial product at levels that were lethal to some consumers.
This example highlights the danger that a genetic alteration in an organism can shift the metabolic pathway and cause the production of toxins that might not be detected during some superficial safety tests.
Most of the currently marketed GE crops contain antibiotic resistance marker genes, in addition to the desired trait like insect or herbicide resistance.
There is the risk that the gene can be transferred from the plant to disease causing germs, whether the transgenic maize is used as animal fodder or as a food product for humans. These bacteria would then be immune to antibiotic treatment.
Research on if and to what extent such gene transfer can happen has only recently started, so the available scientific data is incomplete. A recent study published in La Recherche 309, May 1998, indicates that the preconditions for such transfer are now present. In this paper, Professor Patrice Courvalin of the French Pasteur Institute points to the likelihood that antibiotic resistance will transfer from transgenic plants in the environment, and to the potential for transfer in the digestive tract. Widespread cultivation of transgenics, warns this report, will significantly add to already problematic issues of resistant bacteria. There is sufficient scientific proof that
Given the above, current scientific knowledge strongly supports the assumption that antibiotic resistance genes can be taken up from bacteria in the intestines of animals and humans. Experience in normal agricultural practice shows that antibiotic resistances can move from animal pathogens to bacteria that are also harmful to humans.
The risks of the use of antibiotic resistance genes in genetic engineering is often trivialised by the industry, with the argument that a large proportion of the bacteria in our environment is already resistant to antibiotics. In their opinion, occasional gene transfers from genetically modified plants to pathogens is statistically insignificant. Several research results contradict this argument. Novartis often states that about 40-60% of intestinal bacteria are already resistant to Ampicillin and related antibiotics. But they present no scientific data for these figures. An analysis of scientific literature shows that the frequency of antibiotic resistances varies considerably. Depending on the variety of bacteria, and also depending on the country where the research has been carried out, the results are completely different. The percentage of antibiotic resistant germs in samples of one variety of bacteria (Bacteroides fragilis) varied between 3 and 30%, in samples of another bacteria (Shigella) between 5,9 and 80,7%. A general statement of 40-60% is completely unfounded. It also has to be assumed that not every human being carries antibiotic or Ampillicin resistant germs. Each antibiotic therapy is based on the bacteria being and staying sensitive to the chosen antibiotic. Ampicillin antibiotics are widely used in the treatment of human illness as well as on animals. In 1994, for example, 40 million courses of ampicillin were prescribed in the USA (that is, an average of 1 in 6 of the population). Furthermore, the resistance gene present in the transgenic maize confers resistance also against the antibiotics Ampicillin and Amoxy(pen)icillin. To maintain the effectiveness of antibiotics for as long as possible, it is simply irresponsible to put further resistance genes into circulation.
Antibiotic Resistance markers are an unnecessary, obsolete technology
Antibiotic resistance genes do not serve any purpose in transgenic crops. Such resistance genes are used as markers in the laboratory by genetic engineers, to distinguish cells where their engineering of other traits has been successful from those where they failed. If the cells are treated with antibiotics after the gene transfer, only those containing the resistance gene survive - those cells also will be the only ones containing the desired genes, like insect- or herbicide-resistance. Today, it is possible to use other markers instead. It is also possible to remove antibiotic resistance genes after the genetic engineering event.
Because they are unnecessary and dangerous, many regulatory authorities in Europe oppose the use of antibiotic resistance markers. The German GE advisory commission (ZKBS) recommends the rejection of clinically-important antibiotic resistance genes. The French Committee of Prevention and Precaution recommends a ban of all transgenic crops containing antibiotic resistance genes. The US Biosafety Advisory Committee says that antibiotic resistances should not be trivialised. Norway prohibits all transgenic plants with antibiotic resistance. The French government will not allow such plants (other than Novartis's maize, which has already been approved). Several EU-member states such as the United Kingdom, have announced their opposition to the approval of the Novartis maize in Europe.
In the long term, the commercialisation of GE crops could have important socio-economic consequences. For example, the control of the entire domestic seed market by just a few Western-based corporations has implications for national food security. Whole food production chains may find themselves under monopolistic control - from delivery of agricultural inputs (seeds, fertilisers, chemicals, machinery etc.) via the growing of plants up to the harvest and throughout processing. Producers may find themselves obligated to the increased use of specific agro-chemicals necessary to grow specific GE seeds. They may be crushed by transnational corporations supplying increasingly-expensive inputs and purchasing their agricultural outputs at ever lower prices.
Producers may be played off against each other as powerful vertically-integrated firms manipulate markets. Finally, production may shift from small farms to large estates, and from large estates to bio-reactors, with attendant job losses.
Bulgaria has no laws to regulate imports, exports or domestic trade in GE foodstuffs. Until very recently, there was no international agreement requiring segregation of GE-free crops from GE ones and to label bulk commodities to enable traceability. This situation is going to change following agreement on a Biosafety Protocol, under the Convention on Biological Diversity, in late January 2000.
The Biosafety Protocol, agreed by 130 countries, including Bulgaria, gives them rights, for the first time, to restrict imports of GE crops without breaking international trade rules. Until now, it is not politicians, but the EU market – food retailers, like supermarkets and food processors, like Nestle and Unilever – that has responded to consumer concerns about eating GE food and sought to source GE-free crops. To date, the EU and its Member States were unable to block shipments of GE crops and food, for fear of creating barriers to free trade and being taken before the World Trade Organisation Dispute Panel by governments, such as the US, wanting to export GE crops.
With its language on the ‘precautionary principle’, the Biosafety Protocol could set the stage for countries, such as the EU, to close their markets to GE crops without conclusive scientific evidence of harm. Once the Protocol comes into effect, which could take a couple of years, commodity shipments that may contain GMOs will have to be labelled “may contain” genetically modified organisms.
In the meantime, it is likely that the market in the EU will continue to reject GE crops and food, by looking for sources of GE-free commodities in countries like Brazil and Western Europe. Indeed, since approval has still to be given for placing many GE crops on the EU market, the EU has a strong case for banning these imports. Monsanto’s Roundup tolerant maize has still to receive market approval for import into the EU, and hence any contamination of Bulgaria’s maize exports with this maize could be refused.
The countries where most of the GE crops are being grown are the US, Canada, Chile and Argentina. However, the Chief Executive of the American Corn Growers Association recently predicted, on the basis of conversations with farmers and seed salesmen, that GE sowing could fall as much as 25% in 2000. Farmers are worried that the export markets in Europe and Asia are rejecting GE foods, and this may reduce prices and demand for American agricultural products. They are also coming under pressure from environmental and consumer groups in the US who are demanding labelling of GE foods. For example, in July 1999 Gerber (owned by Novartis) and Heinz removed GE ingredients from their baby food in the USA.
Meanwhile, the public debate in the EU is now examining the use of GE animal feed in meat production. Indeed, in late 1999 several UK food retailers, such as Iceland and Tesco, announced that they intend to phase out the use of GE ingredients in animal feed. This is bad news for Bulgarian farmers growing GE crops, like maize, and feeding it to their animals, or selling the GE maize on to produce animal feed.
The tacit acceptance of the cultivation of GE crops by the Bulgarian Government and its administration, could have severe economic repercussions not only on Bulgarian farmers, but also on animal feed producers, the animal husbandry industry, the starch and processed food industries and traders. The latter include grain traders and those specialising in the export of Bulgarian food and animal products.
If Bulgaria continues on the route of GE agriculture, but wants to meet the demands of the EU market by providing GE free crops and food, segregation of crops after harvest and during storage must be ensured to avoid cross-contamination of GE and non-GE. As outlined above, even small scale field tests could contaminate the harvest on neighbouring fields. Segregation would need to be enforced and controlled by an authority with sufficient credibility to satisfy buyers of GE-free, especially those exporting to the EU. Any suspicion of contamination could result in a shipment being tested for GE contamination. The requirement for segregation of GE and GE-free crops would require additional investment in farm and grain storage capacity as well as for certified laboratories capable of detecting GE contamination with the PCR test.
But Bulgaria does have another choice. The Government needs to take control of the situation and announce an immediate moratorium on all releases of GMOs into the environment. This might seem a drastic step, but one that seems to be the only option for Bulgaria. The alternative worst-case scenario is that, due to the absence of adequate segregation and control measures and testing and labelling infrastructure, Bulgarian food products may be altogether banned from most EU markets, and possibly also the domestic market, due to EU harmonisation. This would lead to an economic downturn due to loss of EU markets, bankrupt farmers and difficulties in meeting the requirements of EU Accession.