May 25, 2012
EFSA refutes reasons cited by France to justify EU cultivation ban
MON810 GM maize: EFSA still says it is safe
France issued another national ban on the cultivation of MON810 maize in March this year, shortly after requesting an EU-wide cultivation ban. The French government supported its request with scientific studies that it claims provide evidence of the plant’s harmful impacts on the environment. The European Food Safety Authority (EFSA) was unable to find any convincing evidence in the documentation submitted by France to support the ban. In a scientific opinion published recently, EFSA also evaluated new scientific studies and concludes that neither these, nor the findings of the 2009 and 2010 post-marketing monitoring programmes, provide any new indications of risk.
Non-target organisms like butterflies are, according to EFSA’s scientific assessment, not at risk from Bt maize. However, it recommends precautionary measures, such as border rows of conventional plants, in regions where sensitive butterfly species occur.
In February 2012, the French government submitted a request to the European Commission to refuse reauthorisation of genetically modified Bt maize MON810 in the EU. In the European Union, GM crop plants are only authorised for ten years and must then undergo another risk assessment. EFSA completed this reassessment in 2009 and found no reason not to reauthorise the plant.
However, France believes cultivation of MON810 maize poses risks, in particular to non-target organisms like butterflies and moths, ladybirds, bees and caddis-fly larvae. It also cites the development of resistant pests as a problem, as well as the potential consequences, such as increased use of chemical pesticides. The French government believes effective measures to prevent resistance development, and stricter post-market monitoring rules to protect endangered species would therefore need to be implemented before the plant could be reauthorised. It cites a number of scientific studies to support its claims.
Bt proteins do not accumulate in the soil
One of the problems mentioned in the French document is a possible accumulation of proteins in soil or water bodies. Since Bt maize plants can release Bt protein through their roots, the French government fears there is a danger that large-scale cultivation over several years could lead to dangerous levels of Bt proteins accumulating in the soil. EFSA argues that long-term trials under field conditions have so far failed to identify accumulation of this kind and cites seven different studies published between 2003 and 2011. It also says that, according to published findings, any remains of MON810 plants that might end up in surface water would not pose a risk to aquatic organisms like caddis-fly larvae. The concentrations of Bt proteins from MON810 maize found in these biotopes to date are far lower than the quantities needed to cause harmful effects.
Butterflies and ladybirds not at risk –
but precautionary measures recommended for sensitive butterfly species
One of France’s main arguments against reauthorisation are the potential risks to non-target organisms, including butterflies and ladybirds. EFSA’s scientific opinion points out that, according to published studies, it is very unlikely that these species will come into contact with harmful levels of Bt protein. Model calculations for butterflies have shown that, even in the case of very sensitive species, the population would shrink by less than one per cent in the worst case scenario. As a precaution, EFSA recommends special accompanying measures in the case of endangered butterfly species, such as planting a border strip of non-GM maize around Bt maize fields, and carrying out post-market monitoring in areas where very sensitive species are present. This would need to be assessed and a decision taken in accordance with the local situation. According to EFSA, however, France did not provide any evidence for the existence of sensitive butterfly species in France or other parts of Europe.
A risk to the two-spot ladybird, which was also cited as an argument for a national cultivation ban in Germany in 2009, is, in EFSA’s view, not supported by published scientific findings. In 2009, a team at ETH Zurich published laboratory findings that showed that larvae of the two-spot ladybird can be harmed by Bt protein. A second laboratory study with similar results was published this year. However, the findings and methods used have been questioned and do not, in EFSA’s opinion, provide sufficient evidence of a potential risk to the two-spot ladybird. A number of other studies, including laboratory and field studies, found no effects on these insects.
Pests develop resistance only when farmers fail to take recommended measures
In terms of the risk of pests developing resistance to MON810 maize, EFSA admits that resistant populations of two pest species have emerged in Puerto Rico and South Africa. It argues, however, that in these cases suitable prevention measures had not been carried out. No refugia areas of conventional maize had been set up in the vicinity of the Bt maize fields, or they had been sprayed with chemical insecticides. This decimated the non-resistant pests and greatly encouraged the development of resistant pests. In Europe, however, no resistant pests have emerged so far and appropriate measures to prevent resistance development are recommended by EFSA.
EFSA also assessed the possibility of secondary pests spreading as a result of Bt maize cultivation, but found there were no new scientific findings to suggest this.
The European Commission is now legally entitled, based on the EFSA report, to ask France to lift its national cultivation ban. This was confirmed by a spokesperson for the European Commissioner for Health and Consumer Policy, John Dalli. In Brussels, however, the expectation is that the Commission will wait to see what position the new government under socialist President François Hollande will adopt with regard to the cultivation ban. This will probably not happen before the French parliamentary elections in June.
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- EFSA: Scientific Opinion on a request from the EU Commission related to the emergency measure notified by France on genetically modified maize MON 810
- DG Sanco: Mesures d’urgence concernant la mise en culture des semences de maïs génétiquement modifié MON810
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