Safety of Genetically Modified Food: Public Interest and Reality

1         Summery

Genetically modified (GM) foods are any foods obtained from plants, animals or microorganisms in which original genetic makeup is deliberately changed by using recombinant DNA technology with one or more altered characteristics. GM foods are matter of significant public controversy in many countries of the world. Many public healths related and environment related issues have been raised against the GM foods. Significant trade dispute have been experienced among different countries regarding export and import of these products. Attitudes of peoples and authorities of different countries vary regarding GM foods and their effects on health and environment. This article will try to discuss the issues raised against GM foods and reality behind those issues. Public attitudes and technical scientific knowledge about GM foods will also be discussed briefly.  Safety and regulation of GM foods will also be reviewed briefly. 

2         Introduction

Foods obtained from plants or animals in which natural genetic makeup is deliberately altered by combining genes of different species for specific purpose by DNA recombinant technology are generally called genetically modified (GM) food [1, 2, 3]. Although genetically engineered products were tried in different forms previously like high solid containing potato in 1967, synthetic growth hormone (recombinant bovine somatotropin) in cattle in 1979, genetically engineered rennet to manufacture cheese in 1990 etc. [3], the first whole GM crop approved for marketing by the authority was tomatoes with better storage property developed in USA in 1992 which was approved as safe for human consumption by US Food and Drug Administration (FDA) and marketed since 1994 [1, 4]. Maize was the first transgenic crop which was approved for field culture in Europe [5]. Tremendous increase in the area of land cultivating genetically modified crop plants in US and other parts of the world have been reported after that [2, 4]. For example, significant proportion of food market in US is occupied by GM foods [3]. Thirty to fifty percent of American corn and soybean are genetically modified for Insect-resistance and herbicide-tolerance [6].

GM food is probably one of the most debated biotechnical innovations with worldwide public controversy.  In spite of several health and economic benefits of GM foods, these are often portrayed as harmful to human health and environment due to limited knowledge about the technology and media propaganda [1]. Public response and regulation of GM food are different countries. Some are more liberal while others are strictly against GM products.

3         Public concerns/attitude towards genetically modified (GM) foods

Genetically modified food is matter of public controversy in many parts of the world. Major debates about the use of GM foods were started in Europe and other countries in 1990s when GM maize and soybean were introduced in the market [2]. Attitudes towards GM foods were found to be varied between individuals and among groups. Some are more concerned towards environmental consequences of GMOs like environmental pollution, evolution of super weeds and new viruses and toxins etc. while others are specifically concerned towards health hazards of GM foods like allergies, carcinogenicity, antibiotic resistance and fear of other unintended and unknown harmful effects on health [2, 3]. Europeans were found to be more sceptics to GM foods than people of the other parts of the world [7, 8]. Public showed their disapproval to biotechnology by forming pressure groups and non-governmental organizations to protest modern biosciences like animal and human cloning including GM foods [9]. 

3.1       Public acceptance of GM foods

When choices exist, people try to avoid food associated with negative attributes. People in different countries were found to be reluctant to consume GM foods [10, 11, 12]. Acceptance and rejection of GM foods by the public depends up on how they perceive the risk and benefits associated with the GM foods [2, 9]. Attitudes of the people towards the GM foods were found to be varied in different parts of the world. In a study in Taiwan, people were found ready to accept GM foods if the benefit associated with the food outweigh the perceived risk of the foods [2]. But people were found ready to pay extra amount for non-GM foods [2]. In a recent publication, Knight and Gao [13] reported that people of China had ambiguous view about GM foods and were  found likely to accept GM foods if these foods are cheaper and responsible government authority assure the public about the safety of such products.

In contrast, people in Europe were found to be against the GM foods [10, 11, 14]. Similarly, People of Scandinavian countries were found more reluctant to accept GM foods [15]. However, recent studies has revealed that Europeans are becoming more supportive to GM foods than before [16]. Similarly, McCluskey et al. [17] reported that Japanese were also reluctant to consume GM foods. Although USA is one of the major producers of GM foods (seed and crop), American people were found to prefer non-GM foods to GM foods [12]. But they were found supportive to accept GM foods with obvious benefits [18]. Traill et al. [19] concluded that American are more optimistic to GM technology than Europeans. 

Acceptance or rejection of particular GM foods is the outcome of total weighted perception about risks and benefits associated with the products [20]. Perception of the people about the risks associated with the products is more important than the actual estimation of risks given by the professional [21]. It has been postulated that people often make decision on the basis of their own perception rather than  technical information [21]. However, public attitude and perception is the outcome of values, beliefs and cumulative technical information they receive over the time. Several other factors like price of the product and trust to the source of information also affects the public acceptance of GM foods [20]. In addition, rather than absolute rejection or acceptance significant proportion of the people  were found undecided [16, 22]  whose decisions would probably be contextual.  

3.2       Major issues raised against GM foods

3.2.1     Health impacts of GM foods

Possibility of producing toxin and allergens by genetically modified crop plants is one of the most frequently debated issues raised by opponents of GM foods. GM foods are often considered to have risk of allergenicity due to possibility of containing novel proteins in these foods [6, 23]. But, it has been claimed that probability of evolving such toxins and allergens are very rare [24]. On the other hand, genetic engineering has been also used to reduce the allergic potential of the food which is described in section 3.2.4 below.

3.2.2     Environmental impacts of GM foods

Impact of genetically modified organisms on environment is another important issue frequently raised against GM foods. Potential cross contamination between GM and non-GM organisms and the spread of GMOs in the environment as an invasive superweed are some major environmental concerns raised against genetically modified organisms [3, 25]. Contrary to this,  DNA recombinant technology has been used to produce different variety of crops and animals which are resistant to different disease and pests [6]. Use of pesticide resistant verities of plants would result in less use of pesticides or use of less potent pesticides which will be advantageous to the environment and beneficial in conserving biodiversity [26].

3.2.3     Ethical issues

Voices against GM foods in cultural, ethical, and religious grounds are equally prominent [2, 9, 27]. Many people consider that the production of genetically engineered products is unnatural and against the nature and general social ethics. However, it is quite difficult to determine what is natural and what is unnatural. There is no rational or unanimously acceptable definition of being natural [26]. Being natural might have different meanings for the people with different social and cultural backgrounds. Therefore, the view of considering GM products as unnatural and unethical has been criticised as insignificant [26]. 

4         What is the reality?

In spite of many benefits of GM foods, peoples were found to be unaware about the technology and truth about the issues raised against GM foods. Scientists and regulatory bodies have been charged to be failed to address the public concern about GM foods which has further intensified the public distrust towards these biotechnological innovations [9]. 

4.1       How GM foods are produced?

GM foods are obtained from genetically modified organisms (crop plants or animals). To produce genetically modified organisms (GMO), gene with desired trait is identified and isolated which is then transferred into the plant or animals destined to be genetically modified by recumbent DNA technology [1]. The interspecies transfer of desired trait is thus achieved. The transferred genes can be used as marker gene to identify the transformed cells and also causes the phenotypic modification in transformed cells with desired characters [1]. Following are the steps to produce GM foods [6, 28, 29, 30].

• First of all desirable trait(s) which has health or economic benefits if transferred into a food crops is identified. For example, pest resistance in maize or higher production of certain vitamin in rice etc.
• Gene(s) responsible for producing selected desirable traits is identified in the organisms other than the crop destined to be genetically modified. Generally bacteria are used as the source of the gene(s). 
• After identification of the gene of interest, such genes are isolated and cloned by using molecular techniques. 
• Genes isolated from microorganisms are naturally can function in microorganisms only. Different bacterial switches should be removed and some other switches should be added to these genes to make these able to function when transferred in higher organisms like plants.
• The isolated genes together with switches are transferred to the cells of organisms (for example crop plants) to be genetically transferred. Different molecular techniques have been developed to transfer genes.
• The transferred cells are then subjected to series of culture and selection to isolate the transferred cells. The transferred cells are then grown into mature plants to produce seeds with desirable traits.

4.2       Advantages from GM foods

4.2.1     Tool to fight against nutritional deficiency

Deficiency of nutrients (vitamins and minerals) is one of the major nutritional problems in developing nations. This issue can be addressed by producing crops with higher vitamins or other nutrients content. For example, Plant geneticists have been able to produce rice varieties with capacity to synthesize higher amount of vitamin A by transferring bacterial gene into rice to fight against vitamin A deficiency [31, 32, 33]. Similarly, different variety of transgenic rice, corn and other vegetables with higher availability of essential minerals like iron and zinc have been developed which are helpful to fight against anaemia and other mineral deficiency [18, 34, 35, 36, 37, 38, 39].  

4.2.2     Increased food production for better food security

The population of the world is increasing at an alarming rate while growth in food production is not keeping pace with the population growth [4]. Deficiency of food will be more severe in developing countries if current rate of population growth and food production trends continues. GM food can be one of the weapons to fight against the global food insecurity by the use of genetically modified crops with higher yields. 

Higher yield rate in crops can be achieved from genetically modified crops in shorter duration than that from conventional plant breeding approaches [3]. Moreover, breeding with genetic engineering is more specific and prognostic thus require less resources and effort in terms of time and money [3]. In addition, transgenic crops have better productivity due to disease and pest resistance. Similarly, development of draught resistance crops by genetic engineering helped to cultivate crops during dry seasons and in area previously unsuitable for cultivation [40, 41, 42]. These developments in genetic engineering obviously help to increase overall food production of the world thus helping to fight against scarcity of food to feed growing world population.

4.2.3     Development of functional foods

Genetic engineering has been used to develop food which can be used as an oral immunizing agent. To develop the foods with this peculiar characteristic, particular gene controlling antigenic properties of the pathogenic microorganisms was selected and transferred to the food crops which eventually developed antigenicity and thus can be used to immunize the consumer against further infection with that pathogen [43]. Scientists have developed a transgenic variety of potato with such immunizing characteristics [44].

4.2.4     Decreasing allergic potential of food

Some of the foods naturally contain proteins capable of producing allergic reaction in the consumer. For example, rice has 14–16 kDa allergenic proteins which can evoke allergic reaction [45]. Although, GM foods were often portrayed as the foods with potential risk of allerginicity, scientists have developed rice variety with reduced expression of the 14–16 kDa allergen genes thus making the rice less risky to cause allergic reaction [46, 47].  Similarly, genetic engineering approach has been successfully used to remove Mal d₁ allergen from apple which can cause birch pollen related food allergies [48]. 

5         Safety of the GM foods

5.1       Are GM foods safe?

It has been argued that there is little scientific evidence for the harmful effects of GM foods [49]. Moreover, many international scientific and public organizations like National Academy of Sciences, the British Royal Society, the World Health Organization (WHO) etc. have endorsed the safety of GM foods for both human health and the environment [2]. GM foods go through very robust and thorough risk assessment process for any allergens, toxins or other harmful effects before they go to market. For example, in Australia and New Zealand a detail risk assessment of the GM foods is carried out by Food Standards Australia New Zealand (FSANZ) before they can be sent to the market [50]. 

In spite of claim of scientists and endorsement of international public organization about safety of genetically modified foods, the GM foods are not of zero risk [24]. Benefits of GM foods may outweigh harms thus inspiring scientists to discover GM foods with new traits. Although risk associated with the GM foods seems to be serious and urgent, they are always rare and preventable if rigorous assessment and precaution is taken before marketing [6, 24]. For example, a variety of transgenic soybean was found to be contained allergen gene transferred from Brazilian nut [51]. This transgenic soybean was, therefore, not marketed [23, 51]. 

5.2       Assessment of the safety of GM foods

Meningaud et al. [24] have suggested to evaluate the safety of the GM foods in the same manner as the evaluation of drugs. The GM foods are only allowed to be sold in the market when it has been assessed for safety by responsible authority of the respective country [28]. Food safety assessment of the GM foods is based on the best current scientific knowledge and carried out individually in every new products fully considering both intended and unintended effects of each new components (DNA and protein) of the GM foods [28]. 

Codex alimentarius commission has published following guidelines and principles for the assessment of the safety of the GM foods.

• Guidelines for the conduct of food safety assessment of foods derived from recombinant-DNA plants [52].
• Guidelines for the conduct of food safety assessment of foods derived from recombinant-DNA animals [53]. 
• Principles for the risk analysis of foods derived from modern biotechnology [54]. 

According to these guidelines and principles, the GM foods should be assessed before marketing for any hazard, nutritional or other safety concern with the nature and severity of the hazard if present. Risk assessment of the GM products should be based up on scientifically sound evidences, information and data[54]. Safety assessment contains the comparison between the GM foods and their non-GM counterparts [54]. Suitable risk management and risk communication procedures should be implemented according to the outcome of risk assessment [54]. Unintended and unexpected should also be duly acknowledged during assessment of the safety of the GM foods [52, 53]. 

Assessment of possible toxicity, assessment of possible allergenicity, compositional analyses of key components, evaluation of altered level of metabolites, potential effects of food processing, compositional changes to key nutrients and health status of modified organism (plants and animals) are some major steps for assessment of the safety of GM foods [52, 53]. 

6         Regulation of the GM foods

Regulation of GM products should be very judgemental because under-regulation may result in the marketing of GM foods without adequate safety assessment and precautions while over-regulation may delay or stop the progress in genetic engineering sector thus preventing the farmers, entrepreneurs and consumers to be benefited from the modern technologies [55]. 

6.1       Regulatory frameworks and Institutions

Regulatory principles, frameworks and approaches for GM foods are dynamic and continuously evolve with advancement in scientific knowledge and societal values [56]. Two types of legislative frameworks, ‘process based’ and ‘product based’, have been used to regulate the GM foods [56]. In the process based legislations, which have been enforced in the European Union (EU) and Australia, GM foods are regulated on the basis of process of genetic transformation [56]. In contrast, GM foods are regulated on the basis of the characteristics of the final product in the product based legislative frameworks enforced in USA and Canada [56]. US regulations are claimed to be chiefly based upon scientific risk assessment while European regulations are based upon precautionary principle [14]. Codex alimentarius commission has published different guidelines and principles mentioned above in 4.2 for international harmonization in this issue.

In Australia, GM foods are regulated through the Gene Technology Act 2000, the Gene Technology Regulation 2001 and the Food Standards Australia New Zealand Act 1991 [28, 50]. Food Standards Australia New Zealand (FSANZ) is the statutory organization responsible for safety evaluation and standard setting of GM foods while the Office of the Gene Technology Regulator (OGTR) administer national policy and issues related to gene technology [28, 50]. Similarly, in USA, the US Food and Drug Administration (FDA) regulates pre-market approval and labelling of GM foods under the Federal Food, Drug and Cosmetic Act [14]. In Europe, GM foods are regulated by the Novel Food Regulation (EC) No. 258/97 adopted from 1997 [14]. This regulation describe the procedure for the approval of GM foods and mandatory labelling provision [14]. Although European Union has given permission to import some GM foods in Europe from 1992 to 1998 according to European Council Directives 90/219/EEC and 90/220/EEC, the Council of the European Union decided to discontinue import of GM products since July 1999 [14]  which was lifted in 2004 due to widespread international protest [57]. Very rigorous and stringent risk assessment procedure was then applied to import GM foods in Europe [57]. 

6.2       Labelling of GM foods

Labelling is the means of communication enabling the consumers to make informed choice. Labelling of GM foods is mandatory in Australia, New Zealand [28] and Europe while this is voluntary in US [20]. In Australia, standard 1.5.2 (food produced using gene technology) has mandatory provision for the labelling of the GM foods [28]. According to the standards any product derived from containing novel DNA or protein or altered characteristics should be labelled as ‘genetically modified’. But, highly processed foods or products which are derived from GM crops (e.g. soybean oil from GM soybean)  but do not contain any traces of DNA or protein are not required to be labelled [28]. In Europe, food products containing at least 1 per cent of GM corn or soybean should be labelled as GM food [14]. Similarly, south American country Argentina has no mandatory GMO levels requirement while another South American country Brazil has mandatory regulation to label GM foods with letter ‘T’ for transgenic products [58]. 

The Codex Committee on Food Labelling (CCFL) was involved in developing standard for the labelling of biotechnology-derived foods [59] but no consensus can be made among different countries about the labelling standards [60].

7         Final remarks

Thus, in spite of many benefits from modern genetic engineering, great deal of public controversy still exist about the use of GM foods in many countries of the world. In spite of some reported health and environmental impacts from these foods, it has been claimed that the advantages of these innovations always outweighs the disadvantages. GM foods could be used as a tool to fight against hunger and malnutrition in developing countries. A person in a less developed country most probably choose to eat GM food with approved safety and risk assessment rather than defeated by hunger, while case may be opposite in developed countries where choices exist. Can we stop using car to get rid of road accident? Should we stop using mobile phones fearing harmful web frequencies?  Thus, it might be better to focus on ethical and prudent use of the product of modern technologies and focus on making these safer and environment friendly rather than going against with the technology guided by unknown and uncertain fears but people have to have right to choose and country have to have sovereignty to decide on these matter without any interference.