Talking About GM

Can GM technology cure the world’s growing pains? On Thursday, 21 January, the BES attended an evening meeting at the British Library at which members of the public, academics, industry representatives and food producers gathered together to discuss this question, considering the contribution which GM crops might make to securing the world’s food supplies. The ‘cafe scientifique’ style event, the latest in the ‘Talk Science’ series organised by the Library’s science, technology and medicine division, was led by Prof. Rosie Hails, CEH and Chair of the Natural Capital Initiative.

Prof. Hails’ main point, in an opening talk which focused on the relationship between agriculture and the environment, was that assessments of the costs and benefits of GM crops have focused too rigidly on biodiversity as an indicator of environmental impact, at the expense of considering other parameters. In assessing these crops, a more holistic viewpoint should be adopted, with consideration of a whole suite of ecosystem services.

Prof. Hails outlined the results of farmscale evaluations, set up in the UK to assess the impact of GM crops on biodiversity. The trials had shown that growing herbicide resistant GM crops did have an impact on biodiversity, as competing weeds were removed. However, if other ecosystem services are taken into consideration, on balance it might be worth adopting these crops and mitigating the impacts on biodiversity in some way – through the introduction of diverse field margins for example. Herbicide resistant crops might be more compatible with low tillage systems and the consequent benefits of these systems for soil structure, nutrient, water and carbon retention may mean that these crops have an overall environmental benefit compared to standard methods of growing crops. Greater data is needed on the environmental impact of GM crops, taking this more holistic view.

Prof. Hails made another important point, not often raised in debates around GM: that GM crops are introduced into variable economic and social conditions. For example, evidence supports the conclusion that those who grow Bt cotton in China (engineered to express a protein toxic to the cotton borer) spray less insecticide. However, it is also possible that because Bt cotton seed is more expensive than non-GM seed, some farmers may adopt a highly protective attitude to their crop and spray it regardless. Prof. Hails stated that ACRE (Advisory Committee on Releases to the Environment) has developed a matrix which assesses a suite of costs and benefits, including social factors, in more detail.

During the course of the ‘Question Time’ style discussion which followed Prof. Hails’ presentation a number of points were put to an audience member representing Monsanto. It was clear that protectionism and monopoly of GM technology by a few large agrochemical companies was a point of contention and source of unease for many. The point was made that EU regulations, currently very strict, should be relaxed to allow small and medium sized businesses to capitalise on GM technology and develop competing products.