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New Study Overturns Claimed Wildlife Benefits of GM Crops

Immediate release (15 Mar 2005)

For more information please contact Sue Mayer (GeneWatch UK) on 01298 871 898; Pete Riley (GM Freeze) on 07903 341 065 or Clare Oxborrow (Friends of the Earth) on 020 7566 1716.

Today, in advance of the announcement of the final results of the Farm-scale Evaluations (FSE) of GM winter oilseed rape next Monday (21st March 2005), GeneWatch UK, the GM Freeze and Friends of the Earth, jointly published two key documents:

  1. A Q&A on the FSE results which are to be announced next week. This highlights the key issues and sets the context for the outcome of the trials. It can be read at: http://www.foe.co.uk/resource/media_briefing/government_to_publish_the.pdf
  2. A new report ‘An analysis of the findings of the BRIGHT trials with GM herbicide tolerant crops in relation to environmental impact’, which overturns the biotech industry claim that the GM crops in the BRIGHT trials, published last November, showed wildlife benefits. The report can be accessed at http://www.genewatch.org. The press release is below.

For more information please contact Sue Mayer (GeneWatch UK) on 01298 871 898; Pete Riley (GM Freeze) on 07903 341 065 or Clare Oxborrow (Friends of the Earth) on 020 7566 1716.

New study overturns claimed wildlife benefits of GM crops
A new, report ‘An analysis of the findings of the BRIGHT trials with GM herbicide tolerant crops in relation to environmental impact’ published today, undermines claims that a four year research project into the growing of GM crops (the BRIGHT trials) showed that they were not harmful to farmland wildlife [1]. The study, conducted for GeneWatch UK, the GM Freeze and Friends of the Earth by the Initiative on Organic Research, reveals that the design of the BRIGHT trials meant that environmental impacts could not be properly investigated (executive summary below).

When the findings of the BRIGHT trials were published in November 2004 [2], the industry body, the Agriculture Biotechnology Council, commented that “We believe this report buries the myth that these two GM crops pose any new problems for farming or the environment”. [3] Mirroring the industry’s interpretation, there were media claims that: “Study finds benefits in GM crops. GM crops are no more harmful to the environment than conventional plant varieties, a major UK study has found” (BBC on 29th November 2004) [4].

However, this new analysis of the BRIGHT trials for GeneWatch, the Five Year Freeze and Friends of the Earth, shows that the media and public were misled. It concludes that:

…while the experimental design is adequate for carrying out a basic herbicide evaluation trial within an arable rotation, there is insufficient replication to determine effects on biodiversity in what is very a varied environment.

and

To fully answer the trial objectives in relation to understanding the environmental effects of GMHT crops was impossible with the level of funding and experimental design. Environmental (botanical) impacts could not be extensively investigated in the trials which were designed to meet a primarily agronomic objective.

The report concluded that in the BRIGHT trials:

  • The only environmental measurements made during the trials were weed seed-bank size and species. There were no measurements of invertebrates, soil microflora, gene flow to wild species, or field margin effects.
  • The environmental measurements were inconclusive. Because insufficient samples of weed seeds were taken at each sampling event, and they were not take frequently enough during the rotation, it is not possible to draw firm conclusions about the changes in the composition of the weed seed-banks, or the impact of these changes in terms of biodiversity.
  • In addition, the new analysis by the Initiative on Organic Research highlights that some of the findings of the BRIGHT trials actually suggest that there could be long-term problems with growing GM herbicide tolerant beet and oilseed rape:
  • The trials showed that some important weeds are not properly controlled by the herbicides used with GMHT crops, so farmers would need to increase use of more toxic herbicides to control them. Gene flow from GM to non-GM oilseed rape and gene stacking (where more than one GM trait is acquired), was shown to be a real risk.
  • The BRIGHT trials found ‘volunteer’ GM oilseed rape plants persisting in following crops, and these could act as a source of future GM contamination.

GeneWatch Director, Dr Sue Mayer said:

The biotech industry was more interested in spinning the results to sound good than in presenting an honest picture of the findings. This approach will not build public confidence in their products.

Director of the GM Freeze, Pete Riley said:

Although the BRIGHT project did provide a lot of new information, claims that GM crops do not harm wildlife simply cannot be justified by the results – the experiment was not designed to investigate this to the level required to draw such conclusions. These results do not provide the basis for predicting the long-term impact GM crops on the wildlife remaining in arable fields.

Friends of the Earth’s GM Campaigner, Clare Oxborrow said:

This new report shows, once again, that the biotech industry will clutch at any straw. But the BRIGHT trials are not the good news about GM crops that the industry claimed; it’s time they stop spinning and start listening to public, who have made their rejection of GM crops and food clear.

Notes to editors:

Turner, R.J., Bond, W. & Pearce, B.D. (2005) An analysis of the findings of the BRIGHT trials with GM herbicide tolerant crops in relation to environmental impact. A report for GeneWatch UK, the GM Freeze and Friends of the Earth. Available at: www.genewatch.org The BRIGHT (Botanical and Rotational Implications of Genetically modified Herbicide Tolerance) project was set up to investigate the growing of GM oilseed rape and sugar beet in a rotation with winter cereal crops from 1998 to 2003. It was funded jointly by the government and the industry. The report was published on 29th November 2004: Sweet J, Simpson E, Law J, Lutman P, Berry K, Payne R, Champion G, May M, Walker K, Wightman P, Lainsbury M (2004). Botanical and rotational implications of genetically modified herbicide tolerance in winter oilseed rape and sugar beet (BRIGHT Project). Project Report No. 353. HGCA. Available on http://www.hgca.com. Agriculture Biotechnology Council Press Release 29th November 2004. BRIGHT puts the spotlight on GM benefits. http://www.abcinformation.org/..
Available at: http://news.bbc.co.uk/2/hi/science/nature/4046427.stm

An analysis of the findings of the BRIGHT trials with GM herbicide tolerant crops in relation to environmental impact – A report for GeneWatch UK, the Five Year Freeze and Friends of the Earth. By RJ Turner, W. Bond, W. & B.D. Pearce

Initiative on Organic Research, March 2005,

Executive summary
This report considers the findings of the BRIGHT project (Botanical and Rotational Implications of Genetically Modified Herbicide Tolerance in winter oilseed rape and sugar beet), a four year study, jointly funded by Government and industry, which was intended to consider the agronomic and environmental issues of growing genetically modified herbicide tolerant crops. The final report of this study was published in November 2004 and the results headlined by the BBC on 29th November 2004 as ‘Study finds benefits in GM crops. GM crops are no more harmful to the environment than conventional plant varieties, a major UK study has found’.

This report addresses whether such headlines were justified and whether, under the experimental approach used in the study, it is even possible to draw meaningful conclusions about the environmental impacts of growing GMHT crops. This report also considers the quality of the economic analysis and identifies potential environmental questions raised by the study.

Objectives and experimental design The stated objectives of the BRIGHT trials were to determine the agronomic and environmental implications of growing GMHT winter oilseed rape and sugar beet in arable rotations and make recommendations to farmers on how to grow these to optimise agricultural benefits, while minimising their effects on the environment.

However, while the experimental design is adequate for carrying out a basic herbicide evaluation trial within an arable rotation, there is insufficient replication to determine effects on biodiversity in what is very a varied environment. Therefore, the results should be considered primarily in an agronomic context.

Methodology
In relation to the determination of environmental impact, only a very restricted range of parameters were measured – weedseed bank size and species. There were no measurements of invertebrates, soil microflora, gene flow to wild species, or field margin effects.

Even though weed seedbank measurements formed the main assessment of environmental impact tested in the experiments, the weed seed data and subsequent analysis was inadequate to draw firm conclusions on the changes in the composition of the weed seedbanks or the impact of these changes in terms of biodiversity. To draw such conclusions would have required much greater resources. There were insufficient samples taken at each sampling event, and they were not take frequently enough during the rotation.

Only a fraction of the soil in each sample was processed, reducing the precision of the analysis even further. As a result, a reliable estimate of seed density can only be made for weed species with seeds present in relatively high numbers. Even for these species, there can be rapid changes in numbers over a single season, depending on when the samples are taken. When weeds are present in low numbers in the soil seedbank, such a high number of soil cores are needed for a reliable estimate that the sampling becomes impracticable. Finally, while it is true that any plant species can add to biodiversity a large proportion of the weed seed-bank increase appears to be attributable to the high number of volunteer crop seeds.

Another limitation is that the study did not compare the effect of different types of cultivation on the results. All the fields in the study were cultivated by ploughing, and so the impact of GMHT crops in other systems, such as minimum tillage or no tillage, was not considered in the experiment. In addition, all trials were based at intensively farmed sites, which have species diversity levels far too low to be representative of the average farm. The soil types at the trial sites were also very similar.

Statistical analysis
The statistical analyses do not appear able to account for, or overcome, the inherent variability of the existing weed populations at the trial sites. This indicates that little confidence can be placed in the reasons suggested for the changes in weeds and their seeds. There seemed to be a struggle to find appropriate statistical tests from the range that were tried. Ideally, the analysis methods should have been determined at the planning stage as part of the experimental design. This raises serious questions about the robustness of the analysis and conclusions.

Economic analysis
The economic analysis includes far too many speculative variables to be meaningful. It also considered a very narrow range of costs and excluded others such as: removal of bolters in beet; more complex spray programmes to control weeds not controlled by the main herbicide; extra cultivation to manage seed shed at OSR harvest; possible loss of GM free status; insurance required to grow GM crops; and risks associated with being tied to a single supplier of seed and herbicide.

Environmental issues arising from the research
Whilst the trials could not investigate environmental effects properly, several issues emerged which could be of future concern including: the potential for increased use of more toxic herbicides to control weeds poorly controlled by the broad spectrum herbicides used with GMHT crops in the trial. Viola arvensis was poorly controlled by glufosinate and Urtica urens poorly controlled by glyphosate; that gene flow from GM to non-GM oilseed rape and gene stacking (where more than one GM trait is acquired), is a real risk. Monitoring of out crossing between the various oilseed cultivars was limited to the experimental plots which meant cross pollination rates were only recorded for relatively short distances (up to 91 metres). The data showed out crossing occurred at all sites and average rates for conventional varieties ranged from 0.3% to 0.9% with peaks of 4.2%. When the predominantly male sterile variety Synergy was tested the highest level found was 9.7%; that volunteer oilseed rape is likely to persist as a source of future GM contamination. Following OSR crop harvest, appreciable numbers of seeds were predicted to persist at trial sites and further monitoring of the sites is required; the possible emergence of herbicide tolerant weed beet and associated need for increased herbicide use. The emergence of weed beet itself is a much more complex process than the production of herbicide tolerant oilseed rape volunteers, but once HT weed beet begins to appear, continued use of the herbicide that it can tolerate will encourage it to multiply further. Herbicide tolerant weed beet are a potentially serious problem as current control relies mainly on glyphosate or expensive hand pulling; that difficult-to-control volunteer oilseed rape weeds which have multiple herbicide resistance may well occur if management guidelines are not followed. The BRIGHT researchers concluded that using HT crops would have little direct impact on subsequent crops but there are management issues where crops grown later in the rotation share the same herbicide tolerance and where conventional crops that follow GM ones risk seed contamination

Conclusions
To fully answer the trial objectives in relation to understanding the environmental effects of GMHT crops was impossible with the level of funding and experimental design. Environmental (botanical) impacts could not be extensively investigated in the trials which were designed to meet a primarily agronomic objective. Therefore, the trials should be seen as a small piece in a large jigsaw puzzle aimed at understanding potential effects of introducing GM technology into British farming systems. Headlines that suggest that the BRIGHT trials showed that GMHT crops do not harm the environment, misrepresent the results of a complex four-year study and do an injustice to scientists who have undertaken the research.

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Download the full study here.