20 QUESTIONS ON GENETICALLY MODIFIED (GM) FOODS
Q1. What are genetically modified (GM) organisms and GM
These questions and answers have been prepared by WHO in
response to questions and concerns by a number of WHO Member State Governments
with regard to the nature and safety of genetically modified food.
Genetically modified organisms (GMOs) can be defined as
organisms in which the genetic material (DNA) has been altered in a way that
does not occur naturally. The technology is often called “modern biotechnology”
or “gene technology”, sometimes also “recombinant DNA technology” or “genetic
engineering”. It allows selected individual genes to be transferred from one
organism into another, also between non-related species.
Such methods are used to create GM plants – which are then
used to grow GM food crops.
Q2. Why are GM foods produced?
GM foods are developed – and marketed – because there is
some perceived advantage either to the producer or consumer of these foods.
This is meant to translate into a product with a lower price, greater benefit
(in terms of durability or nutritional value) or both. Initially GM seed
developers wanted their products to be accepted by producers so have
concentrated on innovations that farmers (and the food industry more generally)
The initial objective for developing plants based on GM
organisms was to improve crop protection. The GM crops currently on the market
are mainly aimed at an increased level of crop protection through the
introduction of resistance against plant diseases caused by insects or viruses
or through increased tolerance towards herbicides.
Insect resistance is achieved by incorporating into the food
plant the gene for toxin production from the bacterium Bacillus thuringiensis
(BT). This toxin is currently used as a conventional insecticide in agriculture
and is safe for human consumption. GM crops that permanently produce this toxin
have been shown to require lower quantities of insecticides in specific
situations, e.g. where pest pressure is high.
Virus resistance is achieved through the introduction of a
gene from certain viruses which cause disease in plants. Virus resistance makes
plants less susceptible to diseases caused by such viruses, resulting in higher
Herbicide tolerance is achieved through the introduction of
a gene from a bacterium conveying resistance to some herbicides. In situations
where weed pressure is high, the use of such crops has resulted in a reduction
in the quantity of the herbicides used.
Q3. Are GM foods assessed differently from traditional
Generally consumers consider that traditional foods (that
have often been eaten for thousands of years) are safe. When new foods are
developed by natural methods, some of the existing characteristics of foods can
be altered, either in a positive or a negative way National food authorities
may be called upon to examine traditional foods, but this is not always the
case. Indeed, new plants developed through traditional breeding techniques may
not be evaluated rigorously using risk assessment techniques.
With GM foods most national authorities consider that
specific assessments are necessary. Specific systems have been set up for the
rigorous evaluation of GM organisms and GM foods relative to both human health
and the environment. Similar evaluations are generally not performed for
traditional foods. Hence there is a significant difference in the evaluation
process prior to marketing for these two groups of food.
One of the objectives of the WHO Food Safety Programme is to
assist national authorities in the identification of foods that should be
subject to risk assessment, including GM foods, and to recommend the correct
Q4. How are the potential risks to human health
The safety assessment of GM foods generally investigates:
(a) direct health effects (toxicity), (b) tendencies to provoke allergic
reaction (allergenicity); (c) specific components thought to have nutritional
or toxic properties; (d) the stability of the inserted gene; (e) nutritional
effects associated with genetic modification; and (f) any unintended effects
which could result from the gene insertion.
Q5. What are the main issues of concern for human health?
While theoretical discussions have covered a broad range of
aspects, the three main issues debated are tendencies to provoke allergic
reaction (allergenicity), gene transfer and out crossing.
Allergenicity. As a matter of principle, the transfer of
genes from commonly allergenic foods is discouraged unless it can be
demonstrated that the protein product of the transferred gene is not
allergenic. While traditionally developed foods are not generally tested for
allergenicity, protocols for tests for GM foods have been evaluated by the Food
and Agriculture Organization of the United Nations (FAO) and WHO. No allergic
effects have been found relative to GM foods currently on the market.
Gene transfer. Gene transfer from GM foods to cells of the
body or to bacteria in the gastrointestinal tract would cause concern if the
transferred genetic material adversely affects human health. This would be
particularly relevant if antibiotic resistance genes, used in creating GMOs,
were to be transferred. Although the probability of transfer is low, the use of
technology without antibiotic resistance genes has been encouraged by a recent
FAO/WHO expert panel.
Out crossing. The movement of genes from GM plants into
conventional crops or related species in the wild (referred to as “out crossing”),
as well as the mixing of crops derived from conventional seeds with those grown
using GM crops, may have an indirect effect on food safety and food security.
This risk is real, as was shown when traces of a maize type which was only approved
for feed use appeared in maize products for human consumption in the United
States of America. Several countries have adopted strategies to reduce mixing,
including a clear separation of the fields within which GM crops and
conventional crops are grown.
Feasibility and methods for post-marketing monitoring of GM
food products, for the continued surveillance of the safety of GM food
products, are under discussion.
Q6. How is a risk assessment for the environment
Environmental risk assessments cover both the GMO concerned
and the potential receiving environment. The assessment process includes
evaluation of the characteristics of the GMO and its effect and stability in
the environment, combined with ecological characteristics of the environment in
which the introduction will take place. The assessment also includes unintended
effects which could result from the insertion of the new gene.
Q7. What are the issues of concern for the environment?
Issues of concern include: the capability of the GMO to
escape and potentially introduce the engineered genes into wild populations;
the persistence of the gene after the GMO has been harvested; the
susceptibility of non-target organisms (e.g. insects which are not pests) to
the gene product; the stability of the gene; the reduction in the spectrum of
other plants including loss of biodiversity; and increased use of chemicals in
agriculture. The environmental safety aspects of GM crops vary considerably
according to local conditions.
Current investigations focus on: the potentially detrimental
effect on beneficial insects or a faster induction of resistant insects; the
potential generation of new plant pathogens; the potential detrimental
consequences for plant biodiversity and wildlife, and a decreased use of the
important practice of crop rotation in certain local situations; and the
movement of herbicide resistance genes to other plants.
Q8. Are GM foods safe?
Different GM organisms include different genes inserted in
different ways. This means that individual GM foods and their safety should be
assessed on a case-by-case basis and that it is not possible to make general
statements on the safety of all GM foods.
GM foods currently available on the international market
have passed risk assessments and are not likely to present risks for human
health. In addition, no effects on human health have been shown as a result of
the consumption of such foods by the general population in the countries where
they have been approved. Continuous use of risk assessments based on the Codex
principles and, where appropriate, including post market monitoring, should
form the basis for evaluating the safety of GM foods.
Q9. How are GM foods regulated nationally?
The way governments have regulated GM foods varies. In some
countries GM foods are not yet regulated. Countries which have legislation in
place focus primarily on assessment of risks for consumer health. Countries
which have provisions for GM foods usually also regulate GMOs in general,
taking into account health and environmental risks, as well as control- and
trade-related issues (such as potential testing and labeling regimes). In view
of the dynamics of the debate on GM foods, legislation is likely to continue to
Q10. What kind of GM foods are on the market
All GM crops available on the international market today
have been designed using one of three basic traits: resistance to insect
damage; resistance to viral infections; and tolerance towards certain
herbicides. All the genes used to modify crops are derived from microorganisms.
Q11. What happens when GM foods are traded
No specific international regulatory systems are currently
in place. However, several international organizations are involved in
developing protocols for GMOs.
The Codex Alimentarius Commission (Codex) is the joint
FAO/WHO body responsible for compiling the standards, codes of practice,
guidelines and recommendations that constitute the Codex Alimentarius: the
international food code. Codex is developing principles for the human health
risk analysis of GM foods. The premise of these principles dictates a premarket
assessment, performed on a case-by-case basis and including an evaluation of
both direct effects (from the inserted gene) and unintended effects (that may
arise as a consequence of insertion of the new gene). The principles are at an
advanced stage of development and are expected to be adopted in July 2003.
Codex principles do not have a binding effect on national legislation, but are
referred to specifically in the Sanitary and Phytosanitary Agreement of the
World Trade Organization (SPS Agreement), and can be used as a reference in
case of trade disputes.
The Cartagena Protocol on Biosafety (CPB), an environmental
treaty legally binding for its Parties, regulates transboundary movements of
living modified organisms (LMOs). GM foods are within the scope of the Protocol
only if they contain LMOs that are capable of transferring or replicating
genetic material. The cornerstone of the CPB is a requirement that exporters
seek consent from importers before the first shipment of LMOs intended for
release into the environment. The Protocol will enter into force 90 days after
the 50th country has ratified it, which may be in early 2003 in view of the accelerated
depositions registered since June 2002.
Q12. Have GM products on the international market passed
a risk assessment?
The GM products that are currently on the international
market have all passed risk assessments conducted by national authorities. These
different assessments in general follow the same basic principles, including an
assessment of environmental and human health risk. These assessments are thorough;
they have not indicated any risk to human health.
Q13. Why has there been concern about GM foods among some
politicians, public interest groups and consumers, especially in Europe?
Since the first introduction on the market in the mid-1990s
of a major GM food (herbicide-resistant soybeans), there has been increasing
concern about such food among politicians, activists and consumers, especially
in Europe. Several factors are involved.
In the late 1980s – early 1990s, the results of decades of
molecular research reached the public domain. Until that time, consumers were
generally not very aware of the potential of this research. In the case of
food, consumers started to wonder about safety because they perceive that
modern biotechnology is leading to the creation of new species.
Consumers frequently ask, “what is in it for me?”. Where
medicines are concerned, many consumers more readily accept biotechnology as
beneficial for their health (e.g. medicines with improved treatment potential).
In the case of the first GM foods introduced onto the European market, the
products were of no apparent direct benefit to consumers (not cheaper, no
increased shelf-life, no better taste). The potential for GM seeds to result in
bigger yields per cultivated area should lead to lower prices. However, public
attention has focused on the risk side of the risk-benefit equation.
Consumer confidence in the safety of food supplies in Europe
has decreased significantly as a result of a number of food scares that took
place in the second half of the 1990s that are unrelated to GM foods. This has
also had an impact on discussions about the acceptability of GM foods.
Consumers have questioned the validity of risk assessments, both with regard to
consumer health and environmental risks, focusing in particular on long-term
effects. Other topics for debate by consumer organizations have included
allergenicity and antimicrobial resistance. Consumer concerns have triggered a
discussion on the desirability of labeling GM foods, allowing an informed
choice. At the same time, it has proved difficult to detect traces of GMOs in
foods: this means that very low concentrations often cannot be detected.
Q14. How has this concern affected the marketing of GM
foods in the European Union?
The public concerns about GM food and GMOs in general have
had a significant impact on the marketing of GM products in the European Union
(EU). In fact, they have resulted in the so-called moratorium on approval of GM
products to be placed on the market. Marketing of GM food and GMOs in general
are the subject of extensive legislation. Community legislation has been in
place since the early 1990s. The procedure for approval of the release of GMOs
into the environment is rather complex and basically requires agreement between
the Member States and the European Commission. Between 1991 and 1998, the
marketing of 18 GMOs was authorized in the EU by a Commission decision.
As of October 1998, no further authorizations have been
granted and there are currently 12 applications pending. Some Member States
have invoked a safeguard clause to temporarily ban the placing on the market in
their country of GM maize and oilseed rape products. There are currently nine
ongoing cases. Eight of these have been examined by the Scientific Committee on
Plants, which in all cases deemed that the information submitted by Member
States did not justify their bans.
During the 1990s, the regulatory framework was further
extended and refined in response to the legitimate concerns of citizens,
consumer organizations and economic operators (described under Question 13). A
revised directive will come into force in October 2002. It will update and
strengthen the existing rules concerning the process of risk assessment, risk
management and decision-making with regard to the release of GMOs into the
environment. The new directive also foresees mandatory monitoring of long-term
effects associated with the interaction between GMOs and the environment.
Labeling in the EU is mandatory for products derived from
modern biotechnology or products containing GM organisms. Legislation also
addresses the problem of accidental contamination of conventional food by GM
material. It introduces a 1% minimum threshold for DNA or protein resulting
from genetic modification, below which labeling is not required.
In 2001, the European Commission adopted two new legislative
proposals on GMOs concerning traceability, reinforcing current labeling rules
and streamlining the authorization procedure for GMOs in food and feed and for
their deliberate release into the environment.
The European Commission is of the opinion that these new
proposals, building on existing legislation, aim to address the concerns of
Member States and to build consumer confidence in the authorization of GM
products. The Commission expects that adoption of these proposals will pave the
way for resuming the authorization of new GM products in the EU.
Q15. What is the state of public debate on GM foods in
other regions of the world?
The release of GMOs into the environment and the marketing
of GM foods have resulted in a public debate in many parts of the world. This
debate is likely to continue, probably in the broader context of other uses of
biotechnology (e.g. in human medicine) and their consequences for human
societies. Even though the issues under debate are usually very similar (costs
and benefits, safety issues), the outcome of the debate differs from country to
country. On issues such as labeling and traceability of GM foods as a way to
address consumer concerns, there is no consensus to date. This has become
apparent during discussions within the Codex Alimentarius Commission over the
past few years. Despite the lack of consensus on these topics, significant
progress has been made on the harmonization of views concerning risk
assessment. The Codex Alimentarius Commission is about to adopt principles on
premarket risk assessment, and the provisions of the Cartagena Protocol on
Biosafety also reveal a growing understanding at the international level.
Most recently, the humanitarian crisis in southern Africa
has drawn attention to the use of GM food as food aid in emergency situations.
A number of governments in the region raised concerns relating to environmental
and food safety fears. Although workable solutions have been found for
distribution of milled grain in some countries, others have restricted the use
of GM food aid and obtained commodities which do not contain GMOs.
Q16. Are people’s reactions related to the different
attitudes to food in various regions of the world?
Depending on the region of the world, people often have
different attitudes to food. In addition to nutritional value, food often has
societal and historical connotations, and in some instances may have religious
importance. Technological modification of food and food production can evoke a
negative response among consumers, especially in the absence of good
communication on risk assessment efforts and cost/benefit evaluations.
Q17. Are there implications for the rights of farmers to
own their crops?
Yes, intellectual property rights are likely to be an
element in the debate on GM foods, with an impact on the rights of farmers.
Intellectual property rights (IPRs), especially patenting obligations of the
TRIPS Agreement (an agreement under the World Trade Organization concerning
trade-related aspects of intellectual property rights) have been discussed in
the light of their consequences on the further availability of a diversity of
crops. In the context of the related subject of the use of gene technology in
medicine, WHO has reviewed the conflict between IPRs and an equal access to
genetic resources and the sharing of benefits. The review has considered
potential problems of monopolization and doubts about new patent regulations in
the field of genetic sequences in human medicine. Such considerations are
likely to also affect the debate on GM foods.
Q18. Why are certain groups concerned about the growing
influence of the chemical industry on agriculture?
Certain groups are concerned about what they consider to be
an undesirable level of control of seed markets by a few chemical companies.
Sustainable agriculture and biodiversity benefit most from the use of a rich
variety of crops, both in terms of good crop protection practices as well as
from the perspective of society at large and the values attached to food. These
groups fear that as a result of the interest of the chemical industry in seed
markets, the range of varieties used by farmers may be reduced mainly to GM crops.
This would impact on the food basket of a society as well as in the long run on
crop protection (for example, with the development of resistance against insect
pests and tolerance of certain herbicides). The exclusive use of
herbicide-tolerant GM crops would also make the farmer dependent on these
chemicals. These groups fear a dominant position of the chemical industry in
agricultural development, a trend which they do not consider to be sustainable.
Q19. What further developments can be expected in the area
Future GM organisms are likely to include plants with
improved disease or drought resistance, crops with increased nutrient levels,
fish species with enhanced growth characteristics and plants or animals
producing pharmaceutically important proteins such as vaccines. At the
international level, the response to new developments can be found in the
expert consultations organized by FAO and WHO in 2000 and 2001, and the
subsequent work of the Codex ad hoc Task Force on Foods Derived from Biotechnology.
This work has resulted in an improved and harmonized framework for the risk
assessment of GM foods in general. Specific questions, such as the evaluation
of allergenicity of GM foods or the safety of foods derived from GM
microorganisms, have been covered and an expert consultation organized by FAO
and WHO will focus on foods derived from GM animals in 2003.
Q20. What is WHO doing to improve the evaluation of GM
WHO will take an active role in relation to GM foods,
primarily for two reasons:
(1) on the grounds that public health could benefit
enormously from the potential of biotechnology, for example, from an increase
in the nutrient content of foods, decreased allergenicity and more efficient
food production; and (2) based on the need to examine the potential negative
effects on human health of the consumption of food produced through genetic
modification, also at the global level. It is clear that modern technologies
must be thoroughly evaluated if they are to constitute a true improvement in
the way food is produced. Such evaluations must be holistic and all-inclusive,
and cannot stop at the previously separated, non-coherent systems of evaluation
focusing solely on human health or environmental effects in isolation.
Work is therefore under way in WHO to present a broader view
of the evaluation of GM foods in order to enable the consideration of other
important factors. This more holistic evaluation of GM organisms and GM
products will consider not only safety but also food security, social and
ethical aspects, access and capacity building. International work in this new
direction presupposes the involvement of other key international organizations
in this area. As a first step, the WHO Executive Board will discuss the content
of a WHO report covering this subject in January 2003. The report is being
developed in collaboration with other key organizations, notably FAO and the
United Nations Environment Programme (UNEP). It is hoped that this report could
form the basis for a future initiative towards a more systematic, coordinated,
multi-organizational and international evaluation of certain GM foods.