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BRITISH MEDICAL ASSOCIATION
Board of Science and Education
The Impact of Genetic Modification on Agriculture, Food and
Health
An Interim Statement
May 1999
CONTENTS
Introduction 1
Genetically modified organisms in the food chain 2
An international perspective 3
GM crops - the regulatory process 5
Environmental impact of GM crops 6
GM food - the regulatory process 7
Health and environmental concerns about GM foods 9
Allergenicity 9
Toxicity of transgenes 9
Antibiotic resistance 10
Protecting the environment and human health 10
Recommendations 12
Environmental precautions and public health risks 12
Further research 13
Regulatory process 14
Third world development 14
Consumer choice - areas of public concern 15
Annex 1: Current structure of the GMO advisory committees in the United
Kingdom 16
Annex 2: Glossary 17
References 18
Introduction
"Evolution is all about assembling the improbable by tiny steps; and not
until the unlikely has been reached do we notice just what it can do.
Genetically engineered organisms will, like any other creature, evolve to
deal with their new condition. It is fairly certain that some of them
will cause problems. Low risk is not no risk. The question is one which
is universal in economics - will the benefits outweigh the costs?" (Steve
Jones, 1993)
Genetic modification involves the insertion of genes from one organism
into another to produce altered genetic material (DNA). The technology is
being used to alter certain properties of food crops - for example, to
make plants herbicide resistant, or delay rotting in tomatoes. As its use
has become more widespread and sophisticated, there is increased public
concern over the safety of genetically modified plants, within the food
chain and within human foodstuffs.
The BMA through its Board of Science and Education has taken sustained
interest in the environmental impact of agricultural chemicals and
agricultural practices. In 1992 the BMA policy report Pesticides,
Chemicals and Health considered the use of genetically modified (GM)
herbicide resistant plants as alternatives to the use of pesticides. The
report reflected the view of the Royal Commission on Environmental
Pollution (published in 1989) that it is "essential that the release of
genetically modified organisms (GMOs) is conducted from the outset under
appropriate
statutory control". In 1994 a further BMA report stated that "The
techniques of genetic modification have the potential through application
in agriculture, medicine and technology to increase the well-being of
people and to promote the health of the population by disease prevention".
The BMA also recognised that "At this stage in the development and
application of genetic modification it is not possible to provide any
guarantees against, or insurance for mistakes. When we seek to optimise
the benefits over risks, it is therefore prudent to err on the side of
caution and above all to learn from our accumulating experience".
The concern with risk assessment and the environment has been further
examined in the 1998 BMA publication Health and Environmental Impact
Assessment - it concluded that decisions regarding the environment and
health should be evidence based and that where there is uncertainty the
precautionary principle should always be applied.
Recent uncertainty over the effects of planting GM crops and the
consumption of GM foods has led to some concern in the medical profession
over the regulation and safety of GM foodstuffs. At the BMA's Annual
Representative Meeting in 1998 it was resolved that:
"This Meeting is concerned about the impact that genetically modified
foodstuffs may have on our long-term health and calls upon the BMA Board
of Science and Education to examine objectively the scientific evidence
and commercial pressures on the issue".
The BMA Board of Science and Education decided that an interim report
should be produced as genetic modification techniques are quickly evolving
and are the subject of fast moving political debate and legislation. The
interim report considers some of the main health, environmental and
regulatory concerns that have been raised over GM foodstuffs, and presents
recommendations which will inform the wider decision making process.
This paper will focus on the use of GM products in foodstuffs, and does
not directly address the use of GM products in pharmaceuticals. GM
products in pharmaceutical products are of great potential therapeutic
benefit, and are licensed and controlled under the Medicines Act. They
are therefore subjected to separate and rigorous tests, including
extensive toxicological testing, and comprehensive risk assessment.
The BMA believes that any conclusion upon the safety of introducing
genetically modified materials into the UK is premature as there is
insufficient evidence to inform the decision making process at present.
Genetically modified organisms in the food chain
Many people face serious difficulties in obtaining secure and affordable
food. It is argued by some politicians and scientists that this problem
is in part due to inadequacies in crop types - ie in resistance to heat,
drought or other adverse conditions - or to crops having a limited ability
to obtain nutrients from the soil.
In addition, many crops have low yield that might be improved by genetic
modification (as may response to growth promoters, or resistance to
attacks from pests and diseases). The argument is then made that genetic
modification might offer better sources of sustainable food for starving
peoples, by addressing some of the factors responsible for low crop
yields.
It has been argued that genetic engineering techniques might also allow
the reduction of allergens in the food chain and decrease the use of
herbicides and pesticides in the environment. There may also be economic
benefits to the consumer (ie reduced food prices and prolonged storage
times). Genetic engineering might also improve the nutritional value of
food or could be used to introduce pharmaceutical agents into foodstuffs
which could have medical benefits.
An alternative view is that GMOs are designed only to increase
profitability in the developed world and offer little to the developing
world, and that better distribution networks are more likely to have a
lasting effect. Of particular concern is the possibility that the use of
GM crops may lead to widespread use of one type of GM crop in developing
nations; and the use of a 'terminator gene' that requires the annual
purchase of new seed could lead to economic problems particularly for
third world farmers. Other potential risks include loss of diversity in
the gene pool and the chance that widespread crop failure could follow the
emergence of a pest with resistance to the specific pest control methods
used.
The BMA accepts that there are potential benefits of GMOs and foods, but
believes that it is most important that a comprehensive cost benefit and
health impact assessment, comparing genetic modification with other
agriculture techniques is implemented. Apart from the obviously critical
issue of environmental impact, such an assessment would need to examine
how people with least access to sustainable food supplies could be best
helped.
An international perspective
Public attitudes to GMOs in Europe differ from those in the USA.
Arguably, the British experience of BSE, which was also of significant
importance within mainland Europe, has affected public confidence in
science and in agriculture, and increased concerns about GMOs.
The BMA believes that the current public mistrust of science, expert
opinion and agriculture, following the BSE crisis, cannot be
underestimated. Scientists, farmers and politicians have much work to do
to re-establish public trust. A cautious approach, requiring further
research into the health and environmental effects of GMOs, should help in
this endeavour.
In addition some of the geo-physical differences between farms in Europe
and the US reinforces concern about the ability to limit contamination
from GM trial or commercial sites into the general agricultural arena.
Thus farms which are extremely large may be better able to tolerate GMOs
without a significant risk of contamination from neighbouring farms. The
lack of admixture of 'wild' land and farmed land in the US may also reduce
the ecological sensitivity - unlike British farms with their systems of
hedgerows and ditches. The risk that a gene can escape from transgenic
organisms and contaminate related species capable of inheriting them is
therefore greater in the UK. The differences between the UK and the US
should also be seen in the context that farmland constitutes 70% of the
UK's land area, and only 10% of the US.
The BMA believes that evidence of environmental safety from the USA may
not necessarily be relevant to the British or European farming scenes.
The effect of GMOs on wildlife and the ecosystem are not yet known.
There has been considerable development of field trials of GMOs within the
UK and mainland Europe. According to the Soil Association there have been
around 500 trial sites for GM crops in the UK - 45 consents for planting
were given in winter/spring 1999; the majority of sites are situated in
East Anglia. Limited and monitored commercial planting of GM crops may
start in
the UK in the year 2000.
The main types of GM crops under development for use in the UK are oilseed
rape, sugar beet, fodder beet, maize and potatoes. Three GM food
products are currently on sale for human consumption in this country -
tomato paste, soya and maize. Genetically modified chymosin is also
available and used as a vegetable alternative to rennet in vegetarian
cheeses. The market for
these products is substantial, 60% of processed foodstuffs contain soya
produce.
The Royal Society reported that in 1998, GM soya accounted for 8 million
hectares (30%) of US soya production; it is likely to increase to 19
million hectares (approximately 65%) in 1999, and is a major US export.
Other EU countries have expressed concern over GM foodstuffs - Austria and
Luxembourg have banned the commercialisation of genetically modified Bt
maize; Greece has banned the commercialisation of GM oilseed rape and
France has introduced a two year moratorium on all transgenic plants with
wild relatives in Europe, pending further research.
GM crops - the regulatory process
Regulation of GM crops and of GM foods is complex. Concerns have been
expressed by the public as well as by scientists on whether the advice is
sufficiently robust, and independent, with a sufficient international
dimension.
GM crops in the UK are regulated by the Genetically Modified Organisms
(Deliberate Release) Regulations 1992 (as amended 1995 and 1997).
Applications must contain a full risk assessment, and are submitted to the
Department of the Environment Transport and the Regions (DETR) and
reviewed by other relevant Government Departments such as MAFF (Ministry
of Agriculture, Fisheries and Food) and Department of Health.
Applications are also reviewed by the Advisory Committee on Releases to
the Environment (ACRE). Trial sites of GM crops are inspected by the
Health and Safety Executive. Applications to market the product are sent
to all EU Member States (a diagram of the regulatory process for GM foods
and crops can be found in Annex 1).
The BMA believes that applications to grow GM crops, whether in trials or
eventually commercially, must be subject to rigorous assessment. The
regulatory process must, as its first task, consult widely on the content
and context of all applications.
Unfortunately, current risk assessment selectively identifies hazards to
be considered and therefore cannot be considered comprehensive.
Longer-term environmental and economic effects may have health
consequences, and need to be sufficiently considered and regulated at both
national and international levels.
The Government has recently announced that it is replacing 10 members of
the 13 member advisory committee ACRE with independent members without
links to the biotechnology industry in order to achieve a better balance
of opinion, and has stated that the committee will address the indirect
and longer-term cumulative effects of GM crops.
The BMA believes that independent post-planting surveillance using
previously identified scientifically acceptable markers of environmental
hazard must be organised before planting becomes more widespread.
Most field trials of GM crops have been carried out in carefully
controlled conditions. There is concern that they may not demonstrate
accurately the potential for environmental contamination and ecological
impact. Further trials are needed to examine these issues and until their
results are known there should be a moratorium on further expansion of the
planting of commercially produced GM crops.
Environmental impact of GM crops
There are concerns over the possible environmental consequences of GM crop
planting in the UK. There are fears that herbicide use may increase,
killing other species; or that transgenic herbicide resistant crops will
contaminate wild relatives to create 'superweeds'. Herbicide-resistant
transgenic
oilseed rape, has already hybridised with several wild relatives. In
addition the development of transgenic plants with built-in insecticide
has led to acquired resistance by insect populations.
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 herbicide. This may lead to an
increase in the average level of insecticide or herbicide residues in
food, and have a negative effect on beneficial insects and wildlife. In
addition fewer varieties of seed may be available, particularly at low
prices.
The current ACRE recommended standard separation of 200 metres between GM
and non-GM trial maize crops is intended to prevent cross pollination (the
distance for other crops can be far less, depending on the type of
modification and how far a particular crop has progressed through the
regulatory process). However recent studies suggest these are inadequate,
as they underestimate the effects of conditions such as moderate wind
speeds. Additional concerns have also been expressed about the role of
bees disseminating GM pollen over wide distances from trial sites. It
must be remembered that once a GMO is released into the environment it can
never be recalled.
GM food - the regulatory process
The use of GM plants in foodstuffs is regulated by the Novel Foods
Regulations. Applications to use genetically modified organisms in food
are sent to MAFF and are considered by the Advisory Committee on Novel
Food and Processes (ACNFP). Labelling issues are considered by the Food
Advisory Committee (FAC), and policed by Trading Standards officers.
Regulatory procedures are increasingly determined at EU level. In
September 1998 new EU rules came into force which requires GM soya and
maize ingredients to be labelled. However, this does not cover certain GM
oils and additives.
Food producers in the US have refused to separate GM from non-GM
soyabeans, making it impossible for many retailers and consumers to avoid
the modified beans. Some producers have insisted that segregation is
impractical. This contrasts with the fact that farmers are prohibited
from keeping any of their harvest seeds for subsequent seasons and are
therefore obliged to segregate at the field and on the farm.
The biotechnology industry has claimed that labelling would be unfair
unless evidence of adverse health effects could be proven, but if there
were proven adverse health effects that would be grounds for a ban (or
restrictions), rather than labelling.
The BMA believes that, however difficult for some producers, consumers
have a right to expect that all foods are labelled as to whether they
contain GMO derived products.
The new Food Standards Agency (FSA) as proposed in the draft Bill will
oversee the work of the ACNFP, and should take an increasingly central
role in the decision making process on GMOs. It should consider the
definition of a GMO and how labelling regulations should be formulated.
It may be too simplistic to regard all genetically modified plants or
food, as one category, either safe or dangerous - and each individual case
will need to be examined carefully.
The BMA believes that the new Food Standards Agency should be introduced
urgently to act as a single, independent regulatory body and oversee all
issue relating to GMOs. Its remit must include the direct and indirect
impact of GM crops and their cumulative effects on the environment and on
plant, animal and human health. The Agency should act as a central point
of research on food matters and have statutory power to take action
anywhere in the food chain from 'plough to plate'. This regulatory body
must have the necessary powers of enforcement to deal with a wealthy and
powerful industry.
The BMA believes that the Food Standards Agency must be demonstrably
independent from vested interests and must be able to influence Government
decisions. A powerful FSA should work with a European wide body to
achieve regulatory coherence in member states.
Some researchers argue that too little is yet known of matters such as
allergenicity of GM foodstuffs for certain predictions to be made, yet
the current regulations do not require research on substances which are
held to be substantially the same as natural products. The principle of
'substantial equivalence' is used for assessing GM food safety, it
involves comparing a new product to one already accepted as safe. This
concept does not account for gene interaction of unexpected kinds which
may take place in GM foods. The possibility that certain novel genes
inserted into food may cause problems to humans is a real possibility, and
'substantial equivalence' is a rule which can be used to evade this
biological fact. For example, tomatoes modified by inserting a gene
designed to slow down the softening process and allow it to retain its
flavour on the vine, were considered 'equivalent' to normal tomatoes as
there were no differences in major vitamin, protein and mineral content
compared to normal tomatoes and therefore were not subject
to further safety assessment (only producers presenting foods considered
not 'substantially equivalent' are required to provide extensive research
data which may include long-term animal feeding trials).
On the basis of the Precautionary Principle, we question the assumption of
'substantial equivalence', and ask what risk assessment has been carried
out to consider the health effects of GM foods.
Health and environmental concerns about GM foods
Concerns have been expressed over the health effects of GM foods, such
concerns include the potential problems of allergenicity, the transfer of
antibiotic resistance in the food chain, and possible toxicity of
genetically modified products.
Allergenicity
Transgenic products may adversely affect people suffering from allergies.
Soyabean containing genetic material from brazil nuts cause reactions in
individuals allergic to nuts (animal experiments suggested that
allergenicity would not be a problem). It is essential that tests for
allergenicity are improved and that such potential allergens are labelled.
The BMA believes that more research on issues around allergenicity and
possible toxicity of GM foodstuffs needs to be undertaken.
Toxicity of transgenes
Information about the effect of genetic modification on the chemical
composition of food and in particular its safety is needed urgently.
Concern has been expressed over an experiment which claimed to show that
snowdrop lectins in GM potatoes had toxic effects on mice. The researcher
(Dr Pusztai) at the Rowett Institute in Aberdeen claimed in August 1998
that genetically modified potato damaged rat organs and depressed their
immune system. At present there is still controversy relating to the
significance
of these experiments. The Government has stated in response to Dr
Pusztai's experiment, that there are no GM potatoes on the market and
there is scientific disagreement about the validity of experiments using
lectins which are harmful in their natural state. However, the experiment
indicates a clear need for careful testing of GM foods. In a separate
experiment research was conducted on the use of the snowdrop lectin in GM
potatoes at the Scottish Crop Research Institute where studies have
indicated reduced fertility in ladybirds fed on aphids reared on potatoes
expressing lectin genes. This may indicate that such altered crops can
have a detrimental effect to beneficial insects.
The Royal Society's Council expert panel, concluded that the chance of
gene transfer happening is slight, but that this possibility must be kept
under consideration. At present it is not possible to predict how
transgenic organisms will behave in the natural environment, and risks
associated with
GMOs are difficult to assess.
Antibiotic resistance
Current transgenic plants may contain antibiotic resistance marker genes -
some tomato pastes and tomatoes carry a marker gene for kanamycin
resistance. Genetically engineered maize uses a marker gene which gives
resistance to ampicillin. Initially, it was feared that antibiotic
resistant
maize may be fed to animals, and the gene might be transferred to bacteria
in the animals' guts and transmit antibiotic resistant organisms to human
beings via the foodchain. The Advisory Committee on Novel Foods and
Processes declared that there was a small chance that antibiotic
resistance could be transferred by the ampicillin-resistant gene to
animals fed the unprocessed genetically engineered maize, and that it may
compromise the use of veterinary medicine. This decision was overruled by
the European Union Scientific Committees who concluded that the risk was
too small to recommend a ban for its use in animal feed.
The BMA believes that the use of antibiotic resistant marker genes in GM
foodstuffs is a completely unacceptable risk, however slight, to human
health.
The use of antibiotic resistance marker genes has been criticised by both
the Royal Society and House of Lords Select Committee on the European
Communities. The House of Lords Select Committee has called for them to
be phased out of GM food production.
Protecting the environment and human health
This paper reviews the current regulatory processes for GM foods and GM
crops, and considers the policy positions of Government, advisory
committees, and prominent Non-Governmental Organisations (NGOs) concerned
with health and the environment. Care should be taken over the
introduction of GM crops to the UK, as our agricultural geography differs
widely from that in the US, and the natural wildlife is therefore more
vulnerable to potential changes in the environment resulting from GMO
release. In particular we consider that there is a need for more
comprehensive risk assessments which include interactions between GMOs and
the long-term effects on health and the environment, the introduction of
clear and comprehensive labelling for GM food, and a greater degree of
openness in decision making. We would like to see independently funded
and reviewed
research in the public domain which considers the long-term health and
environmental impact of GM crop planting, and the consumption of GM food.
We believe that given adequate risk assessment procedures, independent and
rigorous testing, adequate post marketing surveillance and proper
regulation, genetically modified food could benefit both developed and
underdeveloped nations. It is vital that regulatory procedures are
strengthened and enforced, and that public confidence is restored through
transparency of information.
The BMA believes that public awareness of GM crop sites could be enhanced
if applications for GM crop sites are prominently displayed in local
newspapers and crop sites are clearly identified for example by public
information notices, subject to local authority planning permission.
Nothing in life is free of risk. When something is judged to be 'safe' it
merely falls within acceptable limits of risk. The best strategy for
dealing with environmental risks, where we are confronted by profound
uncertainties, is to act cautiously, and to embark on a systematic
programme of research to improve our understanding; an approach known as
the 'precautionary principle'. This principle should be applied for the
foreseeable future to GM crop release and the introduction of GM products
into the food chain, until the health and environmental impact of GMOs are
fully assessed and in the public domain.
Recommendations
Environmental precautions and public health risks
1 The precautionary principle should be applied in developing genetically
modified crops or foodstuffs, as we cannot at present know whether there
are any serious risks to the environment or to human health involved in
producing GM crops or consuming GM food products. Adverse effects are
likely to be irreversible; once GMOs are released into the environment
they cannot be subject to control. It is therefore essential that release
does not take place until the level of scientific certainty is sufficient
to make the risk acceptable. This will require a comprehensive
cost/benefit and health impact assessment, comparing genetic modification
with other forms of agricultural
engineering. The BMA has provided guidance on how health and
environmental impact assessment could be conducted to assist in
determining the degree of environmental risk.
2 Careful consideration needs to be given to the effect of GMOs on farming
practices, the countryside and wildlife and we therefore recommend a
moratorium on the commercial planting of GM crops in the UK. The
moratorium should continue until there is scientific consensus (or as
close agreement as reasonably achievable) about the potential long-term
environmental effects.
3 GM foodstuffs should be segregated at source, to enable identification
and traceability of GM products. This is important as there are
considerable doubts about the behaviour of GMOs once they are released
into the environment, and this will also facilitate monitoring in the
interests of
public health. It is unacceptable that at present some GM and non-GM
products are mixed at source, and are not adequately labelled.
4 If the biotechnology industry persists with its stance of mixing GM and
non-GM products the Food Standards Agency should consider banning imports
of such products (until such time that possible hazards, if any, have been
identified) or insist that such products are labelled to indicate that
there
is no guarantee that products are GM free.
5 The regulatory committee approved standard separation distance between
GM and non-GM crops should be reviewed in the light of new research on the
risks of cross pollination.
6 There should be a ban on the use of antibiotic resistance marker genes
in GM food, as the risk to human health from antibiotic resistance
developing in micro-organisms is one of the major public health threats
that will be faced in the 21st Century. The risk that antibiotic
resistance may be passed on to bacteria affecting human beings, through
marker genes in the food chain, is one that cannot at present be ruled
out.
7 Because of the potential scale of use of GM material in the environment
and in the food chain, there is a need for a considerable strengthening of
the UK disease surveillance systems, both in their scope and depth.
Disease surveillance and event monitoring procedures will need to be
sufficiently robust to deal with the potential emergence of new diseases
associated with GM material which will be obscure and difficult to
diagnose.
8 The risk that GM crops may increase the use of herbicides and
pesticides in the environment needs to be comprehensively assessed to
determine their full environmental impact. Biotechnology companies must
provide satisfactory evidence that such chemical use will not increase -
otherwise the use of such GM crops must be regarded as being
environmentally unacceptable.
Further research
9 The BMA is concerned that while genetically modified foodstuffs could
contribute substantially to improving nutrition and health (not only
because good nutrition leads to good health but because vaccinations could
be carried out through administration of GM foods), further research needs
to be conducted on the possible health risks of GM foods consumption. In
particular further research is needed on the mechanisms of allergic
reaction to GM products and the health risks arising from antibiotic
resistance.
10 There should be more long-term research into the environmental effects
of GMOs - in particular to consider the cumulative effect of GMOs in the
environment and the food chain and the fate of metabolic (or digestive)
transgenic DNA in animals and human beings.
Regulatory process
11 The Food Standards Agency with statutory power should be introduced
urgently and as a priority consider the wider and long-term implications
of GM food on human health. This will provide greater regulatory
coherence than the current case by case approach to GMO production and
consumption, and provide a single reference point for research on all
aspects of the food chain, from 'plough to plate'. The inclusion of
medical experts in existing and new advisory committees is essential.
12 Once a scientific consensus is reached on the safety of GM crop
planting, the Food Standards Agency should introduce new regulatory
controls to conduct post-release monitoring and surveillance of
commercially grown GM crops.
13 Comprehensive health and environmental impact assessments should be
applied to all GM crop site applications, and be open to public scrutiny.
Evidence of safety submitted by Biotechnology companies should be openly
presented and subject to critical peer review. Commercial secrecy should
not take precedence to openness of information in matters relating to
public health.
14 Breaches of crop site regulations should be met with appropriate
fiscal measures. In particular, fines for companies which ignore legally
required risk control measures should be of a sufficient nature to act as
an effective deterrent.
Third world development
15 Regulatory procedures in the third world should be as rigorous as
those in developed nations in order to prevent companies escaping legal
constraints. There should be a co-ordinated effort by industries and
governments worldwide to ensure that the regulations and provisions
affecting GM products do not favour the developed countries at the expense
of other more vulnerable developing nations.
16 Export of GM foods to developing countries should be carefully
monitored to ensure that packaging, labelling and possible environmental
consequences are fully regulated.
17 The UK Government should consult with European and other governments
to support a review of the World Trade Agreement to ensure that
governments rather than companies determine whether countries accept with,
or without restrictions, the importation and use of GM seeds, plants or
foods.
Consumer choice - areas of public concern
18 Governments should ensure that non-genetically modified foods continue
to be widely available and affordable to consumers, and that GM foods are
labelled in a consistent and understandable manner.
19 More information on new scientific technologies, especially
developments in biotechnology, should be made available to the public.
This should include information about the costs and benefits in terms of
health, the environment, the economy and other social considerations. The
Government and the biotechnology industry should not ignore public
concerns, and must seek
to allay fears through greater dialogue, effective consultation and
transparency of information. This should include a centralised
information service for public enquiries relating to GMOs, and an easily
accessible database of trial crop site consents, and research evidence.
Unless public
confidence over GM crops and GM food is considerably enhanced, there is a
danger that medical biotechnological advances will be similarly rejected
by the public, at great cost to medical progress. |