Proposals on GM seed purity sow doubt on all sides

Plant breeders and environmental groups alike have criticised an early draft of a forthcoming European Commission proposal to prevent conventional seeds being contaminated with genetically modified varieties. They describe them as "unworkable" and "inequitable."

The Commission promised last year to draw up rules on seed purity specifically to cover contamination by GM seeds. It was reacting to an international controversy in which Canadian maize which had been contaminated with a GM variety was planted in several European countries (ENDS Report 304, pp3-4 ).

A working paper has now been drafted by Commission officials in preparation for a formal proposal for a Commission Directive this autumn. This would amend six existing Council Directives on different seed groups: beet, fodder plants, cereals, seed potatoes, oil and fibre plants, and vegetables.

The paper proposes setting varying thresholds for the "adventitious" contamination of seed lots by GM seeds which have been authorised by the EU. These depend on the pollination mechanism of each plant. They are:

  • 0.3% for cross-pollinating species other than maize and beet and some vegetable plants which are cross-pollinated but are cultivated vegetatively.

  • 0.5% for self-pollinating species other than soya and field peas. The threshold would also apply to maize, beet, potatoes and vegetable plants excluded from the above category.

  • 0.7% for soya and field peas.

    More lenient thresholds are specified for some plants because there is considered to be a lower risk of their seeds lying dormant and producing "volunteer" plants which could germinate and pollinate non-GM plants subsequently grown with them.

    Each threshold is intended to allow for factors - such as multiple contamination at different stages of the seed life cycle - which might lead to concentration of GM impurities. Ultimately, the aim is to ensure that producers can meet the limit of 1% adventitious presence of GM material in food and feed proposed by the Commission in July (ENDS Report 319, pp 50-51 ).

    The thresholds apply to the adventitious presence of GM crops which have been fully approved by the EU. The working paper proposes a ban on the presence of any other GM material. However, it also envisages that this clause would have to be reviewed if Member States accept the controversial proposal made by the Commission in July to allow the presence of GM material which has been approved by EU scientists, even if it has not gone through the full authorisation process.

    The British Society of Plant Breeders (BSPB) says that the proposed thresholds are "unworkable". It claims that in order to meet, say, a 0.3% limit on GM contamination, seeds businesses would in reality have to work to a 0.1% limit to be sure of satisfying detection tests, given the margins of error involved.

    The BSPB's chief executive, Roger Turner, told ENDS that the industry wants a threshold no lower than 1%. He pointed out that the EU's Scientific Committee on Plants (SCP) had warned that the Commission's proposals would be increasingly difficult to achieve as production of GM crops in the EU increases. In fact, the SCP has said that even a 1% threshold may prove to be impracticable in time.

    Seed producers are also dismayed by two other proposals in the working paper. One would oblige them to observe minimum crop rotation periods so as to avoid contamination by GM volunteer plants previously grown in the same fields.

    The second would specify isolation distances between three crops and their nearest GM relatives which are much greater than those under current seed purity rules. For hybrid swede and turnip rape, for instance, the proposal is for a distance of 3,000 or 5,000 metres, depending on whether the crop is basic or certified. For beet, the proposed isolation distance is 2,000 metres. For all other crops, best practice would have to be followed to minimise pollen transfer, except in areas designated as GM-free zones by Member States.

    Commission officials had originally wanted to propose that isolation distances between all crops and their GM relatives be doubled, but the SCP advised that there was insufficient scientific evidence to justify this. For winter oilseed rape, the SCP said, even a doubling of the distance was unlikely to be sufficient to prevent GM pollen transfer.

    Seed producers say that the proposals would make it increasingly difficult and costly to find suitable seed growing locations. In addition, they claim, insurers will become reluctant to cover crops because of the increasing risk that they may fall foul of the proposed restrictions.

    The BSPB argues that there should be no binding rules on rotation periods or isolation distances, just a requirement that best practice be followed. Environmental groups, however, are calling for the converse.

    But a point on which the BSPB and environmental groups agree is the inequity of the proposals. They put the onus on conventional seed producers to ensure that their crops do not become contaminated.

    Friends of the Earth argues that the burden should instead be placed on GM seed producers to take all necessary measures to avoid GM "pollution". According to the BSPB, the proposals could - ironically - price smaller conventional seed producers out of the market to the benefit of larger firms more likely to be interested in GM technology.

  • Please sign in or register to continue.

    Sign in to continue reading

    Having trouble signing in?

    Contact Customer Support at
    or call 020 8267 8120

    Subscribe for full access

    or Register for limited access

    Already subscribe but don't have a password?
    Activate your web account here