Professor Mark Partridge and Professor Denis Murphy, from the biotechnology unit at the University of Glamorgan in Wales tested 25 products containing soya using an EU approved method for detecting traces of GM ingredients.
They found that 10 of the 25 samples tested positive for traces of GM ingredients, even though eight of the positive samples had been labelled 'GM free' or 'organic'. Four of the products that showed traces of GM were above the UK Soil Association's limit for organic food, including one vegetarian sausage mix which contained 0.7 per cent GM soya.
'We have recently observed that many soya products now carry 'GM free' or 'organic' labels, both of which imply an absence of GM ingredients in these foods,' said Professor Murphy. 'However, most of the soya now produced in the world comes from GM varieties.
'Given that GM soya production is set to increase even more over the coming years, it is difficult to see how 'GM free' labels can be justified unless there is much more rigorous testing of such foods,' he concluded.
Supporters of GM food production in Europe were dealt a blow on 2 February when the Belgian government rejected an EU wide application by German company Bayer CropScience to grow herbicide tolerant oilseed rape.
In reaching its decision, the government took advice from a biosafety expert group. In its report, the group is believed to have referred to the results of the recent GM field trials in the UK, which found evidence that herbicide tolerant oilseed rape reduces biodiversity.
Had Belgium approved the application by Bayer CropScience, the file would have been forwarded to the European Council for a final decision on cultivating the crop throughout the EU. In light of Belgium's rejection of the application, however, EU wide approval now appears highly unlikely.
A spokesperson for Bayer CropScience rejected the idea that the decision was based on scientific evidence: 'We have serious concerns about the way the Belgian government handled this. We believe the decision was highly influenced by Belgian politics. The experts raised some concerns but indicated that with proper controls it would be possible to cultivate this crop without impacting on the environment.'
Meanwhile, environmental groups welcomed the verdict. Karen Simal from Greenpeace Belgium said: 'This is a slap in the face of the biotech industry and a victory for the environment. The Belgian government has acknowledged that growing GM oilseed rape is harmful to the environment.'
Full findings of the study will be published in 2 April issue of the British Food Journal (Vol 106 (3) 2004).