Scientific Committee on Plants calls for more research on 'GM free' threshold
The Health and consumer protection Directorate-General's Scientific Committee on Plants (SCP) has warned that it may not be possible to meet the new one per cent labelling threshold for 'GM free' products laid down in recent Commission legislation. The SCP was asked for its opinion following the adoption of a proposal on July 25 this year which stated that the accidental presence of up to one per cent of GM material in food and animal feed should be exempt from GM labelling obligations. In order for this target to be achieved, growers and companies would need to adopt measures which minimise the percentage of GM seed sown in crops and restrict pollen - and therefore gene - flow. The Commission has suggested that in order to achieve the one per cent goal, the frequency of GM seed in planted seed lots should be no higher than 0.3 per cent for cross-pollinating crops (eg: sugar beet) and 0.5 per cent for self-pollinating crops (eg: wheat, rape seed), which are less likely to be fertilised by pollen from neighbouring fields. The SCP states that, with the scientific opinion currently available, the GM seed thresholds suggested by the Commission can only be achieved using ideal production practices. The committee warned there are likely to be many instances where these values may not be achievable, due to pollen flow from neighbouring GM crops and 'spilled' seed from GM crops grown on the same site in previous years ('volunteers'). The SCP warned that these difficulties are likely to increase as GM crop production in Europe rises and the risk of cross-contamination becomes proportionally larger. The committee suggested that the one per cent 'GM free' threshold may eventually need to be re-assessed in the light of ongoing GM crop experience. Other strategies considered by the Commission include doubling the current separation distances between GM and non-GM crops. The SCP threw doubt on the effectiveness of such measures, however, saying that additional precautions may be needed to ensure an acceptable level of crop purity. The committee said that the effectiveness of isolation distances varied according to crop species, and called for further research into hybrid crops in order to clarify the necessary isolation precautions. The SCP suggested that further research is necessary on the impact of 'volunteers' on non-GM plants in order to determine the amounts that can be tolerated in seed and food crops. The Commission also suggested the introduction of specific time gaps during which no GM plants of the same or closely-related species could be grown in fields to be used subsequently for non-GM crops. But the SCP cited a lack of clear data on the persistence times of some species of seed in the soil, making it difficult to calculate the chances of non-GM crops becoming contaminated by 'leftover' GM seed. The committee did, however, accept that there are three broad groupings of species which can be used as guidelines to suggest minimum cropping breaks between GM and non-GM crops: - Short persistence (1 year; eg: soya, maize and field peas) - Medium persistence (2 to 3 years; eg: wheat, field beans, barley) - Long persistence (5 years; eg: oilseed rape, potato, beet) The American Society of Plant Biologists (ASPB) has brought together a collection of essays entitled 'Genetically-modified crops: what do the scientists say?' to provide a platform for the opinion of plant scientists on genetically-modified crops. The publication is a collection of essays which appeared in the ASPB's plant science journal Plant Physiology, between May 2000 and 2001.