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Genetically modified food

Genetic modification (GM) is now possible using biotechnology. The genetic material may be altered with methods that do not occur naturally; this is known as genetic engineering. However, traditional breeding can achieve the same effects but over a much longer time span. Selected individual genes are transferred from one organism to another. The transferred gene may come (as with GM foods), from a non-related species. However, genetic modification of food is not new. For centuries, food crops and animals have been altered through selective breeding. While genes can be transferred during selective breeding, the scope for exchanging genetic material is much wider using genetic engineering. In theory, genetic engineering allows genetic material to be transferred between any organism, including that between plants and animals. A hypothetical example might be a gene from a fish that lives in very cold seas being inserted into a strawberry so it could survive the frost. This has not as yet been done for currently available foods.

Maize, soybean, rape seed oil (canola), chicory, squash and potato are crops that have been modified with approval in a number of countries. They have been modified to make them resistant to insects and viruses and more able to tolerate herbicides. Nutritional enhancement of food crops is now at a advanced stage of research, especially with regards to the world's health problems like iron and vitamin A deficiency.

Modified genes may be present in whole foods, such as soybeans, maize and tomatoes. These GM whole foods are not presently available in Australia. Genetically modified food ingredients are, however, present in some Australian foods. For example, soy flour in bread may have come from imported GM soybeans. Modified genes may have been used in an early stage of the food chain, but may or may not be present in the end product. Gene products e.g phytochemicals may persist in the food chain, to advantage or disadvantage, and this is relevant to consumers.

Genetic engineering can also be used to increase the amount of particular nutrients (like vitamins) in food crops. This technique, sometimes called 'nutritional enhancement' is done at an advanced stage of research, especially in relation to major health problems like iron and vitamin A deficiency and the removal of the protein in peanuts that causes allergies in a small number of people.

Since December 2002, the law in Australia states that food labels must show if food has been genetically modified, or contains genetically modified ingredients, additives or processing aids are present in the final food.

Organic foods are not genetically modified
Foods certified as organic or biodynamic should not contain any GM ingredients according to industry guidelines.

Benefits of GM foods
There is a need to produce inexpensive, safe and nutritious foods to help feed the world's growing population. Genetic modification may provide:
Better quality food.
Higher yields.
Inexpensive and nutritious food, like carrots with more antioxidants
Foods with a greater shelf life, like tomatoes that taste better and last longer.
Food with medicinal benefits, such as edible vaccines.
Crops and produce that require less chemical application.

GM foods are potentially better for the environment. By using genetically engineered crops that are resistant to attack by pests or disease, farmers and primary producers do not have to apply large amounts of pesticides and chemicals to the surrounding environment. Crops are also being produced which are resistant to particular herbicides and pesticides and this may reduce the amount of pesticides used.

The risks of genetically modified crops
Food regulatory authorities require that GM foods receive individual pre-market safety assessments. Also, the of 'substantial equivalence' is used. This means that an existing food is compared with its genetically modified counterpart to find any differences between the existing food and the new product, thus the assessment investigates :
Toxicity (by means consistant with those for conventional foods)
Tendency to provoke any allergic reaction
Stability of the inserted gene
Whether there is any nutritional deficit or change in the GM food
Any other unintended effects of the gene insertion.

A GM food will only be approved for sale if it is safe and as nutritious as its conventional counterparts. The safety of GM foods is still being debated, as it is impossible to predict all of the potential effects on human health and the environment. Some public health experts, however, advocate caution and believe that, ' we are only at the 'scientific starting line, we simply don't know whether GM foods are safe'.

Some concerns which have been raised by scientists, community groups and members of the public include:
New allergens could be inadvertently created - known allergens could be transferred from traditional foods into GM foods. No allergic effects have been found with currently approved GM foods
Antibiotic resistance may develop - bioengineers sometimes insert a 'marker' gene to help them identify whether a new gene has been successfully introduced to the host DNA. One such marker gene is for resistance to particular antibiotics. If genes coded for such resistance enter the food chain the effectiveness of antibiotics could be reduced. Research has shown that the risk is very low, however, there is general agreement that using these markers should be phased out.
Cross breeding - other risks include the potential for cross-breeding between GM crops and surrounding vegetation, including weeds. This could result in weeds that are resistant to herbicides and would thus require a greater use of herbicides, which could lead to soil and water contamination. The environmental safety aspects of GM crops vary considerably according to local conditions.
Pesticide resistant insects - the genetic modification of some crops to permanently produce the natural biopesticide Bacillus thuringiensis (Bt) could encourage the evolution of Bt-resistant insects, rendering the spray ineffective. Wherever pesticides are used insect resistance can occur and good agricultural practice includes strategies to minimise this.
Biodiversity - growing GM crops on a large scale may also have implications for biodiversity, the balance of wildlife and the environment. This is why environmental agencies closely monitor their use.
Cross contamination - plants bioengineered to produce pharmaceuticals (medicines etc) may contaminate food crops. Provisions have been introduced in USA requiring substantial buffer zones, use of separate equipment and a rule that land used for such crops lie fallow for the next year.

Ethical concerns
Concerns about genetic modification include:
The possible monopolisation of the world food market by large multinational companies that control the distribution of GM seeds.
Using genes from animals in plant foods may pose ethical, philosophical or religious problems. For example, eating traces of genetic material from pork for certain religious groups.
Animal welfare could be adversely affected more readily. For example, cows given more potent GM growth hormones could suffer from health problems related to growth or metabolism.
New GM organisms could be patented so that life could become commercial property through patenting.

Labelling of GM foods
Since December 2002, the law in Australia states that food labels must show if food has been genetically modified, or contains genetically modified ingredients. Foods must be labeled as genetically modified or containing genetically modified ingredients if the food contains:
New DNA
New proteins

Special labels are not required for:
'Highly refined' foods where the altered DNA or protein is no longer in the food (for example, oil from modified corn).
GM food additives or processing aids - unless the new DNA remains in the food to which it is added.
GM flavours where less than 0.1per cent is present in the food.
Food, food ingredients or processing aids where GM ingredients are 'unintentionally' present in less than 1 per cent.
Food which is prepared at the point of sale (so takeaway and restaurant food will not have to be labelled).

Labels may be required where:
Genetic modification has altered the food so that its composition or nutritional value is 'outside the normal range' of similar non GM goods. For example if GM technology is used to add vitamins.
Naturally occurring toxins are 'significantly different' compared to similar non GM foods.
The food produced using GM technology contains a 'new factor' which can cause allergic reactions in some people.
Genetic modification raises' significant ethical, cultural and religious concerns' regarding the origin of the genetic material used.

GM food on the shelves
Many foods on supermarket shelves contain imported GM ingredients. A variety of GM foods have also been approved for production in Australia . These foods include corn, soybeans, potatoes and canola. Others are still awaiting approval. Imported food products are subject to the same regulations as domestically manufactured foods.
There are around 20 GM foods, additives, flavourings, growth hormone (bovine somatotropin) and enzymes (like rennet, used to make cheese) currently approved in Europe. In the US there are more than 40 approved GM foods. The main sources of GM foods in Australia include:
Imported soya from the United States. This is one of the main sources of GM ingredients in food sold in Australia since 1996. The soya has been genetically modified to be resistant to a herbicide. It can be found in a wide range of foods, such as chocolates, potato chips, margarine, mayonnaise, biscuits and bread.
Cottonseed oil made from GM cotton (resistant to a pesticide) is also used in Australia. It is used for frying by the food industry, in mayonnaise and salad dressings.
Imported GM corn is mainly used as cattle feed at present and has not been approved for farming in Australia. However, GM corn may have entered the Australian market through imported foods like breakfast cereal, bread, corn chips and gravy mixes, but if so, it is now required to be labelled.
Other GM foods available overseas which may be ingredients in imported foods to Australia include pawpaw, potatoes, canola oil, sugar-beet, yeast, salmon, bananas, barley, carrots, cauliflower, chicory and coffee.

If you want GM free food
Due to consumer demand, some food manufacturers in Australia, have taken steps to provide GM-free food. These products may be labeled accordingly, for example 'contains no genetically modified ingredients'. Although Food Standards Australia New Zealand (FSANZ) does not provide a consumer hotline on GM matters people can make enquiries to the Gene Technology Information Service

Things to remember
There are potential benefits, risks and ethical concerns regarding GM foods that are still being researched and debated.
There is no current evidence that suggests that GM foods are likely to be harmful to health.
GM foods, or foods containing GM ingredients sold in Australia, are required by law to be labeled..

The Healthy Eating Club is the nutrition content provider for the Victorian Government Health website
"Better Health Channel" (BHC) in Australia. The BHC produce Fact Sheets with our help for the general public. They have kindly given us permission to link these articles to our website. The relevant BHC fact sheets are linked under each heading as well as under one heading at the bottom of the "Food & Nutrition Information" index page.

Last Updated: April 2003