Dec 2, 2011
New EFSA risk assessment published
Cultivation of GM maize 1507: No concerns, but precautionary measures for butterflies and moths
The European Food Safety Authority (EFSA) has reassessed the environmental safety of GM maize 1507. According to the new evaluation, approving cultivation of this insect-resistant maize line in the EU would not raise safety concerns. However, certain measures are to be carried out to protect butterflies and moths. The European Commission now has to draw up a new proposal for a Council decision. In 2007, Stavros Dimas, who was the European Environment Commissioner at the time, opposed the authorization of maize 1507.
Butterflies like the peacock butterfly are sensitive to the Bt protein. Generally, these insects eat only very small quantities of it under natural conditions, so there is no risk. However, if Bt maize 1507 is to be grown on large areas, EFSA recommends planting protective strips with conventional maize as a precaution.
In 2007, Stavros Dimas, then European Environment Commissioner, refused to authorize the cultivation of maize 1507 in the EU. Now EFSA has updated and expanded its risk assessment.
EFSA’s Panel on Genetically Modified Organisms (GMOs) first published guidance on the environmental safety of maize 1507 in 2005. Like MON810 maize, which has already been authorized, maize 1507 produces Bt protein to protect itself against European corn borer larvae.
In 2007, European Environment Commissioner Dimas refused to authorize two Bt maize lines – 1507 and Bt11 – for cultivation in the EU. In doing so, he overrode EFSA’s scientific opinion. To justify his decision, Dimas cited possible environmental risks to non-target organisms like butterflies, moths and caddis-flies. Since, in his view, potential long-term risks had not been sufficiently well researched, and there were no suitable research methods available, he believed it was necessary in the interests of the precautionary principle not to authorize the two Bt maize lines for cultivation.
Potential risk applies only to butterflies and moths
EFSA’s GMO Panel has now updated its safety guidance for maize 1507, citing methodological advances and new published scientific studies that are relevant for the environmental risk assessment of maize 1507. In particular, the panel reassessed the potential risk to non-target butterflies and moths.
Using a mathematical model, the scientists calculated the volumes of pollen to which different butterfly and moth species could be exposed. They established that under certain cultivation conditions, a regional risk to sensitive species of butterflies and moths could not be entirely ruled out. Only if the proportion of maize 1507 in a region is below five per cent of the total maize-growing area are no special measures necessary to protect butterflies and moths. Even in the worst case scenario, highly sensitive butterflies and moths are likely to suffer increased mortality amounting to no more than one per cent of the total population.
If maize 1507 is grown on a larger scale, the experts recommend planting buffer strips of conventional maize around the fields of maize 1507. This would mean that the sensitive butterfly and moth species had hardly any contact with the GM pollen. When planting 1507 maize near protected areas, the scientists recommend a minimum separation distance of 30 metres. In addition, they recommend that cultivation of 1507 maize should be accompanied by case-specific monitoring to check the effectiveness of the measures.
The panel also reassessed the risk potential to other non-target organisms, including caddis-flies in water bodies and soil-dwelling arthropods, based on new scientific studies. They came to the conclusion that there are no new findings to suggest that these organisms are at risk.
In order to prevent the development of resistant corn borers, the panel recommends planting refugia of conventional maize if maize 1507 is grown on more than five hectares in a region. These refuge areas are intended to ensure the survival of non-resistant pests in the vicinity of maize 1507 fields.
The new scientific assessment by the EFSA panel relating to the authorisation of maize 1507 for cultivation is now before the European Commission. The Commission has three months to produce a proposal for an authorisation decision for the Standing Committee on Foodstuffs and the Council of Ministers.
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Bt maize: No risk for butterflies and moths
Result of a three-year research project at RWTH Aachen University.