Genetically Engineered Oilseed Rape

Friends of the Earth - Briefing Sheet

Despite research showing possible environmental and agriculture problems, a new type of oilseed rape may soon be planted - making it the first genetically engineered crop grown in the UK. Friends of the Earth is calling for a moratorium on this crop until it can be shown that it won't damage our environment or risk our health.


Genetically engineered foods have become a controversial issue in Europe. A new variety of oilseed rape may be the first genetically engineered (GE) crop to be grown commercially in the UK. It has been designed to be resistant to a weedkiller. Friends of the Earth have serious concerns over the impact this crop will have on farming, public health and the environment. This briefing outlines the issues and our concerns about herbicide resistant oilseed rape.

Oilseed Rape

Oilseed rape is the fourth most widely grown crop in the United Kingdom (1). In 1997 the UK was penalised under world trade rules for producing too much (2). Most (98%) of oilseed rape is grown for the production of food grade oil, while the pulp is used in animal feed. The oil is commonly used for margarines and vegetable oils and derivatives are used throughout the range of cosmetic and detergent products (3).

What is GE oilseed rape?

This genetically engineered oilseed is a new variety which contains a gene from a soil bacterium. This has made it resistant to glufosinate ammonium, a powerful herbicide. By making oilseed rape resistant to this chemical, the herbicide can now be sprayed at any time, killing all the weeds but leaving the crop intact.

Herbicide resistant crops are extremely desirable from an industry point of view as they will increase the market for herbicides. Research has mainly focused upon 2 herbicides: glyphosate (Monsanto's Roundup) and glufosinate (Hoechst's Challenge). It has been estimated that the production of glufosinate resistant crops could increase Hoechst s sales of this product by $200 million per year (4).

Companies have developed herbicide resistant crops as a way to increase the markets of existing herbicides rather than working to develop newer and safer ones, because "the development costs of a new herbicide are up to 20 times higher than those for a new (plant) variety" (5).

What is Glufosinate?

Glufosinate is a non-selective herbicide. This means that it is supposed to kill any plant with which it comes into contact. It is marketed under names such as BASTA, Liberty, Challenge, Harvest and Dash. It is used for completely clearing vegetation, and also as a pre-harvest treatment (particularly in potatoes and oilseed rape) to kill off the foliage, so making it easier to harvest. Recent reports have shown that it is not so effective as first thought, with serious weeds such as thistles and couch grass not being killed off. This has led to other herbicides being used (6).

Which companies are involved?

Most large agrochemical and seed companies, and many smaller ones, are involved in transgenic research. At present, the company attempting to market glufosinate resistant oilseed rape in the UK is Plant Genetic Systems NV, a Belgian company which during 1996 had 75% of its shares bought by AgrEvo. AgrEvo is also producing a glufosinate resistant oilseed rape variety but has not progressed as far as Plant Genetic Systems. AgrEvo is part of Hoechst Schering AgrEvo GmbH, a German company which produces the pesticide glufosinate.

Why are we concerned about glufosinate-resistant oilseed rape?

1. Increased use of glufosinate

At present, glufosinate is not widely used on oilseed rape. It is inevitable that the use of this new seed will increase the use of glufosinate, indeed that is the aim of producing it. Thus any risks to the environment and human health from using this herbicide will be increased.

Although glufosinate residues have been found in harvested oilseeds (7), at present the Ministry of Agriculture, Fisheries and Food does not test for its presence in oilseed products. Despite this, reports show that glufosinate has toxic effects on humans and animals (8), particularly affecting the nervous system. The US Environmental Protection Agency also states that it is toxic at very low concentrations to many aquatic and estuarine invertebrates (9,10).

2. Possible increase in use of pesticides overall

There is evidence that glufosinate tolerant oilseed rape varieties do not show a decrease in the amount of overall herbicides needed in comparison with unmodified crops (11). In addition, a study in Canada showed that some disease-causing fungi are highly resistant to glufosinate (12), whilst important fungi that protect plants from disease are highly susceptible to glufosinate (13). Oilseed rape has a wide range of fungal pests (14) therefore it is possible that widespread use of glufosinate will increase the need to use fungicides.

The production of herbicide resistant seeds also encourages farmers to look upon the use of herbicides as the first choice for weed control. Having bought the herbicide resistant seed, farmers would be far more likely to use the herbicide when before they might have considered this as only one possible option. There are still a number of farmers who think that to have any weeds at all in a field is a sign of bad farming, when in fact a certain level may have no adverse affect upon the crop. The ability to use non-selective herbicides in the crop will further promote this attitude and encourage the use of herbicides, rather than promoting the real needs of the crop. Additionally, some weeds, if exposed often and long enough to a weedkiller, will adapt to this pressure and develop it's own resistance. This may lead to stronger doses being required in the future.

Finally, oilseed rape commonly spreads into other crops as a weed. These too will be resistant to glufosinate so they may have to be controlled using alternative herbicides.

3. Glufosinate tolerance will spread to all oilseed rape

Two neighbouring fields of oilseed cross breed easily. If one field is the genetically engineered variety and the other not, then the two crops may produce seeds for oil production that could contain the genetically engineered material. Research in Scotland has found the new genes 2.5km away from test sites (15). Therefore it is highly likely that if planted on a large scale all oilseed rape will end up contaminated and consumers could never ensure that they were not consuming produce from transgenic oilseed rape. Even organic oilseed products could not be guaranteed. Organic standards do not allow for the presence of genetically modified materials in organic produce so farmers would be unable to produce organic oilseed rape.

4. Glufosinate tolerance will spread to weeds.

Recent studies have shown that transgenic oilseed rape is able to crossbreed with weedy relatives, making those weeds also resistant to herbicides (16). Oilseed rape can cross breed easily with other plants in the Brassica family such as wild turnip and wild radish (17). Research shows that these too can become herbicide resistant if crossed with the genetically engineered oilseed rape. Therefore the prospect of common weeds becoming agriculture pests (often labelled as "superweeds") is very real and may lead to more toxic chemicals being used to control them.

Interestingly, one company at the forefront of this technology, AgrEvo, also agrees, suggesting that "...the farmer can always control these resistant weeds with other products" (18).

5. Plants may develop multiple resistance to herbicides

It has already been proven that herbicide resistance can be passed to conventional oilseed rape and other plants. If the newly resistant plants then comes into contact with oilseed rape resistant to other herbicides eg Roundup, then it is possible that they may develop resistance to both herbicides. As the agrochemical companies are in competition and all are trying to develop the market for their own particular variety, it is possible that adjacent fields of oilseed rape could be resistant to different chemicals. This potential mosaic of different herbicide resistant crops would provide just the right situation for multiple herbicide resistance to arise and stronger, more damaging herbicides may have to be used to control weeds.

6. Oilseed pollen may pollute honey

Honeybees are the primary pollinators of rapeseed (19), and honeybee ecology shows that given a large nectar and pollen source, such as fields of rape in flower, bees will tend to stick to that one source (20). Thus, honey from a hive close to transgenic rapefields will probably contain large quantities of pollen containing transgenic material. A study by researchers at the University of Leicester has found that in honey, pollen DNA and proteins can remain intact after seven weeks in honey (21). In view of the unknown results of genetic engineering it is possible that proteins could be present in honey that could have allergenic or toxic effects for both humans and bees. In addition, bumble bees would be also drawn to such sources of pollen. However, at present no information is available on the possible impacts of genetically engineered oilseed rape on these important insects. More research into the ecological effects of genetically engineered crops is urgently needed.

7. This crop may have adverse impacts on insect and bird populations

At present, broadleaved weeds often grow in amongst oilseed rape crops and provide valuable food and habitats for insects which in turn are a source of food for small mammals and birds (22). The use of glufosinate resistant oilseed would seriously reduce the number of weeds in a field and therefore the amount of food available to insects and birds. This could have a knock-on effect on insect eating mammals and birds. Since 1969 the populations of skylark and grey partridge have fallen by 58% and 82% respectively (23) and this has been blamed largely upon modern farming practices. Therefore, farming should be moving towards systems that will support and build biodiversity rather than adopting practices which may speed up its decline.

8. Spread of Antibiotic Resistance

In order to find out whether the genes researchers want to insert have been successfully transferred, antibiotic resistance is sometimes used as a "marker gene". This is totally unnecessary for the crop in the field, but instead of removing this gene once the research stage has been completed, the antibiotic resistance gene is left in. At least one glufosinate resistant oilseed rape variety carries this antibiotic resistant gene. It is thought that DNA fragments can survive the digestion process (24) thus there is a legitimate worry that antibiotic resistance will be passed further up the food chain. Problems of antibiotic resistance of pathogens is already a problem in medicine. It is obvious that including antibiotic resistance in crops is a dangerous and unnecessary game to play, and may lead to these valuable drugs being less effective on both animals and humans.

9. Bad for farmers?

Using patenting laws, such new crops are usually owned by large agro-chemical companies thus creating conditions where they have a bigger say into how we produce food. Patents may force farmers to buy the seed and herbicide as a pair, thus excluding competitors, and increasing farmers dependence upon the agrochemical companies. Examples of such pairings that already occur include Monsanto s Roundup Ready soybeans. Whether this benefits farmers is highly debatable.

10. Bad for consumers?

Under current legislation, genetically engineered rapeseed oils will not be labelled since oils do not contain proteins (which do have to be labelled). Therefore consumers not wanting to purchase genetically engineered products will be unable to choose to do so.


From the above concerns it is apparent that the growing of genetically engineered oilseed rape may cause serious problems to both nature and farmers.

Genetically engineered plants cannot be recalled or cleaned up like a pollution incident. Once planted the new organisms are 'live' and reproduce in the wild. Yet, despite these concerns, genetically engineered oilseed rape may soon be planted in the UK. Considering the scientific uncertainty it would seem prudent not to plant these crops until we know the full impact. Additionally it could be argued that the science of genetic engineering is far from complete. Do we really know what happens when we insert new genes? What effect will the antibiotic resistance genes have?

We should also be sceptical of the advertised benefits, in this case the supposed reduction in chemical use. From a long term perspective the reverse may be the more likely outcome and we may end up with a farming system that relies on more chemical herbicides with the environmental and health implications that it brings. Whatever the case, more research and public debate is needed before such developments are allowed to happen.

Friends of the Earth position

Friends of Earth is calling for a moratorium on the growing of genetically engineered crops until the implications have been fully evaluated and necessary action taken to avoid environmental damage and any unnecessary risks to human health.

Many questions remain to be answered. Will we end up using more chemicals to produce food? What about bees and other beneficial insects? Will they be harmed in any way? Furthermore, the question of whether we actually need these new varieties is missing not only from public debate but also from the legislative system.

Friends of the Earth is campaigning for sustainable farming practices that don't depend on unnecessary chemical inputs and produces food that is safe to eat and minimises the impact on the environment.

What can I do?

If you support a moratorium then write urgently to your MP, c/o House of Commons, London, SW1A OAA (if you don't know who it is then ring 0171 219 4272). Ask your MP to support a moratorium and take the issue up with the Ministry of Agriculture.

If you would like to choose not to support genetically engineered foods then let your local supermarket know. Ask them to ensure that conventional products are easily available and clearly labelled to enable you to choose what you buy.

Written by Emily Diamand for Friends of the Earth. November 1997.
Friends of the Earth, 26-28 Underwood Street, London, N1 7JQ


1. Pesticide usage Survey Report 141: Arable farm crops in Great Britain 1996. Ministry of Agriculture Fisheries and Food. p.6
2. MAFF helpline, personal correspondence, Nov 1997
3. Kings, 1997.
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5. European Parliament Commission on Agriculture, Fisheries and Food. 1986. Draft report on the use of Biotechnology. Brussels.
6. Pesticide News No 27. Gaps in Basta's effectiveness? Sept 1997.
7. Pesticide Safety Directorate evaluation on: HOE 39866 (Glufosinate Ammonium). 1990. Ministry of Agriculture Fisheries and Food. p.74
8. Cox, C. 1996. Herbicide Factsheet: Glufosinate. J. of Pesticide Reform Vol.16 (4) pp.15-19
9. U.S. EPA. 1990. Estuarine invertebrate toxicity test. HOE 039866 technical. Data Evaluation record. cited in Cox 1996 op cit.
10. U.S. EPA. 1986. Aquatic invertebrate acute toxicity. Soluble concentrate 200g/l. Data Evaluation Record. cited in Cox 1996 op cit.
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14. UK Pesticide Guide 1997. (ed. R. Whitehead). pp.91-92
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18. AgrEvo Homepage:
19. Lackey, J. Rapeseed. USDA APHIS. Biotechnology Permits Document
20. Seeley, T.D. 1985. Honeybee Ecology. Princeton University Press, Princeton, New Jersey.
21. Eady, C., D. Twell, and K. Lindsey. 1995. Pollen viability and transgene expression following storage in honey. Transgenic Research Vol. 4. pp.226-231
22. Royal Society for the Protection of Birds. 1997. Comments on MAFF discussion paper "Weed Control on the Farm: Management of Genetically Modified Herbicide Tolerant Crops". Unpublished
23. Royal Society for the Protection of Birds. 1997. op cit.
24. R. Shubbert et al. "Ingested foreign (phage M13) DNA survives transiently in the gastrointestinal tract and enters the bloodstream of mice". Mol. Gen. Genet 242 pp 495-504

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