Submission of the British Medical Association to the Health and Community Care Committee On The Health Impact Of Gm Crop Trials

Submission of the British Medical Association to the Health and Community Care Committee On The Health Impact Of Gm Crop Trials

In 1999 the BMA’s Board of Science published The Impact of Genetic Modification on Agriculture, Food and Health – an interim statement[i]. At this time, the BMA called for a moratorium on further expansion of the planting of commercially produced Genetically Modified (GM) crops until trials could be assessed for environmental contamination and ecological impact. However, in recent years, the number of crop trials has increased steadily, without public consultation, since their introduction in the UK in the early 1990s.

The BMA report is one of only a few that consider directly the potential health impact of GM crop trials and we would urge the Health and Community Care Committee to consider it as one of the main supporting documents for use during this inquiry.

This written submission also takes into consideration the longer-term use of Genetically Modified Organisms (GMOs), in particular the possibility of growing GM crops for commercial interests and the risks of GM foodstuffs. It is essential that these issues are considered at the earliest opportunity in order to address the future impact of GM crops on the environment and on public health.

Should the Executive prevent GM crop trials from continuing on the grounds that it is against the precautionary principle to allow them to continue?

Yes. As with scientific matters, it can be difficult and time-consuming to demonstrate safety to an acceptable standard. Safety is a relative matter and is generally based on the results of a robust and thorough search for possible harm. There has not yet been a robust and thorough search into the potentially harmful effects of GM foodstuffs on human health. On the basis of the precautionary principle, farm scale trials should not be allowed to continue.

GM crop trials are being held at 178 sites in the UK, 12 of which are in Scotland. GM Crop trials have been authorised by the Scottish Executive to take place at Munlochy, Ross and Cromarty, Daviot, Udny, Tilliecorthy and Rothienorman, Aberdeenshire, Newport-on-Tay, Fife, Invergowrie, Perth and Kinross, and Bilston and Woodhouselea in Midlothian.

Trials have been running in the United States for a number of years now, however evidence of environmental safety from the US may not necessarily be applicable to UK farming circumstances. In the UK, farmland constitutes 70 per cent of land area, whereas in the US it is only 10 per cent. The effects of GMOs on the UK’s wildlife and ecosystem are not yet known.

Prior to farm scale trials, the BMA believes that the crop must be subject to rigorous assessment, including consulting on the content and context of all applications. Longer-term environmental and economic effects may have health consequences and need to be considered and regulated at a national level.

Until these risks are fully understood and quantified by field trials, there should be a moratorium on any further planting of GM crops on a commercial basis. If field trials are to be permitted, the precautionary principle requires the most rigorous safeguards in order to contain any potential risk to a strictly delineated area. In practice, applying a satisfactory safety margin around trial crops in the UK may prove very difficult to achieve, due to the old-established pattern of land usage.

In 1998, the BMA published Health and Environmental Impact Assessment[ii]. It concluded that the decisions regarding the environment and health should be evidence-based and that where there is uncertainty the precautionary principle should always be applied. The concerns doctors have about the impact genetically modified foodstuffs may have on our long-term health are serious enough to warrant a precautionary approach.

There is a precedent to adopt the precautionary principle even where it has not been proven that there is a link. In September this year, the European Court of First Instance upheld a ban on the use of certain antibiotics as additives in animal feed, even though there was no proven link between the use of antibiotics and the potential risks of resistance of these antibiotics in humans. In this particular case it was “possible to take preventative measures without having to wait until the reality and seriousness of the risks perceived become fully apparent.”[iii]

Is the risk of assessment procedure for GM crops currently in place sufficiently robust from a public health perspective?

Following public health disasters such as the BSE crisis and foot and mouth disease, public confidence in the scientific community’s approach to agriculture has been undermined. Scientists, farmers and politicians need to re-establish public trust. Further research is required into the health and environmental effects of GMOs before they can be permitted to be freely cultivated. This must be executed in such a way as not to expose the population to possibly irreversible environmental risk, which may, in turn, have as yet unquantified public health implications.

In the UK, not enough is known to enable us to give an accurate risk assessment of the health impact of GM crops on the health of local communities.

The BMA recommends that the only way to assess the impact on health is to track any subtle changes in the trial areas. Routine health surveillance currently in place would not pick up adverse effects on the health of people living in the vicinity of GMO trial sites in Scotland and indeed is not intended to do so.

In the longer term, the BMA recommends ongoing health monitoring to assess the impact and address questions raised regarding the consumption of GMOs. We would expect food producers to clearly label GM foodstuffs to indicate that they contain GMO derived products. Inevitably, there will be people who make a decision to avoid GMOs based on personal choice, whereas others may consume a lot of GMO foods. Monitoring must look for emerging differences in these groups.

At present instead of making plants more resistant to damaging pests and better able to compete with weeds, many GM researchers are making them more resistant to insecticides and herbicides. This may lead to an increase in insecticide or herbicide residues in food.

The BMA has real concerns that the health of those living close to GM crops may be affected by the use of pesticides. Pesticides are known to have an impact on public health. We do not know the effect of the use of different concentrations of single agents and the BMA recommends further investigation into the impact of this on the public’s health.

Perhaps most worryingly of all, a report by the Royal Society[iv] highlighted the issue of antibiotic resistance. Antibiotic resistance ‘markers’ help identify GM plants and there is evidence that these genes may be transferred to non-GM plants. There is a significant risk that antibiotic resistance markers may progress through the food chain, possibly into pathogenic organisms causing human disease. The BMA supports the Society’s call for further research to determine whether such gene transfer could occur, and to what extent. Although the risk is not yet known, any increase in the number of resistant micro-organisms through the transfer of markers from GM foods would potentially have very serious adverse effects on human health. The BMA believes that the use of antibiotic resistant markers in GM foodstuffs is a completely unacceptable risk, however slight to human health, and we therefore believe that the use of antibiotic resistant markers in GMOs be prohibited immediately.

One further concern is the potential effects of allergenicity on human health from genetically modified products. Transgenic products may adversely affect people suffering from allergies. The BMA believes that further research and tests on GM foodstuffs for allergenicity needs to be undertaken. Until this is completed, there must be an open-ended moratorium on transgenic products, especially introducing nut genes and proteins etc. into cereals.

The BMA would like to see independently funded and reviewed research in the public domain which considers the long term health and environmental health impact of GM crop planting and the consumption of GM food.

Are the guidelines to prevent conventional crops being cross-contaminated by GM crops adequate?

Research monitors weeds and insects in both GM and non-GM crops, and in the margins. Research is also looking into how pollen travels from the GM crop.

A number of crops are being grown as part of the UK trial programme, but oilseed rape is the only GM crop to be trialled in Scotland. Oilseed rape is described as a “high-risk crop for crop-to-crop gene flow and from crop to wild relatives. At the farm scale low levels of gene flow will occur at long distances and thus complete genetic isolation will be difficult to maintain.”[v]

The BMA has concerns about the effect of GMOs on the ecosystem. There is evidence that there is cross-contamination of non-GM crop sites some distance from growing areas and there is some evidence of adverse effects to the local wildlife.

The separation distance between GM and non-GM trial crops is intended to prevent cross pollination. The recommended distances should be reviewed as we believe that they underestimate the effects of conditions such as moderate wind speeds.

“Releasing GMOs into the environment is effectively irreversible as once gone it is impossible to get them back…”
Dr Charles Saunders
Chairman, Scottish Committee for Public Health Medicine and Community Health

Should it be incumbent on the Scottish Executive to monitor the health of people living around GM farm scale evaluation sites?

Yes. The Scottish Parliament has a responsibility to protect the health of the population and it should be incumbent on the Scottish Executive to monitor the health of people living nearby GM crop trial sites. The BMA are disappointed that to date, the Scottish Executive’s have decided not to include health monitoring of local populations as part of the farm scale evaluation programme.

Potential local adverse health effects from GMOs might only effect small numbers of people, any symptoms could be unusual or idiosyncratic, difficult to ascribe to GMOs or take many years before resulting in frank illness. Setting up a specially designed surveillance programme to identify adverse effects would be a complex task. Such a surveillance programme would need to be on a national or UK basis to have the best chance of being effective in picking up potentially rare events.


The BMA believes that insufficient care has been taken with regards to public health and the introduction of GM crops to the UK. We believe there is a greater need for more comprehensive risk assessments which include interactions between GMOs and the long term effects on health and the environment before field trials are taken any further.

GM crop trials present us with profound uncertainties. The BMA recommends that a cautious approach be taken. More research is needed to improve our understanding of the issues. Where there is uncertainty the precautionary principle should always be applied. Extension of the current farm-scale trials would be ill advised and potentially irresponsible until the health and environmental impact is fully assessed and in the public domain.

The BMA would like to see more public consultation on the growing of GM crops in Scotland. The provision of more information to the public on GM crops will increase awareness and understanding of the issues. Information on Local Authority planning applications for GM crop sites should be more publicly available and prominently displayed so that the public have an opportunity to voice their concerns in advance of the trial.

The BMA does not support the argument that GM foods can solve the problems of feeding the starving millions worldwide. There is no global shortage of food; maldistribution of food is the problem. Currently, GMOs benefit the companies and supermarkets involved in the production and distribution of GMO products. The benefits, for example being able to grow crops in adverse conditions, have not yet been proven. Others such as inclusion of vaccines in food crops raise huge concerns about liberties, public trust. It is essential to consider the risk against the perceived benefits.

[i] British Medical Association. The Impact of Genetic Modification on Agriculture, Food and Health – An Interim Statement. London: BMA 1999

[ii] British Medical Association. Health and Environmental Impact Assessment: An Integrated Approach. London: BMA 1994

[iii] Judgements of the European Court of First Instance Press Release 11 September 2002

[iv] The Royal Society. Genetically Modified Plants for Food Use. London: September 1998

[v] European Environment Agency. Genetically modified organisms (GMOs): The significance of gene flow through pollen transfer. Environmental Issue Report No. 28

articles post