Health effects of GM foods need further study, WHO says
assessments on using genetically modified (GM) foods should give
governments pause for thought before giving their approval for
their wider use of the technology.
In a report issued yesterday, the UN body finds that GM foods can increase crop yield, food quality andthe diversity of foods that can be grown in a given area but warns against rushing to introduce novel types of genes into the food chain.
The WHO report further complicates the international dispute over GM foods which has left multinational companies with having to deal with different sets of regulations depending on thecountries in which they operate.
The sale of GM foods has put nations at loggerheads with each other. The EU and Japan have enacted labelling and traceability requirements for GM food products, while the US and Canada believe thetechnology is safe and that such standards are not necessary. The US, Canada and Argentina have filed cases with the World Trade Organisation against the EU's requirements.
WHO calls for a case-by-case risk assessment of each new GM food on its effects on human health, on the food chain and on the environment rather than a general endorsement by governments on the useof the technology to create new types of crops or animals.
WHO notes that pre-market risk assessments have been performed on all GM food products that are currently marketed. To date, the consumption of GM foods has not caused any known negative healtheffects. Currently, evaluations of GM primarily focus on the ecological and agricultural ramifications and on possible health effects.
"However, some of the genes used to manufacture GM foods have not been in the food chain before and the introduction of new genes may cause changes in the existing genetic make-up of thecrop," WHO stated in its assessment. "Therefore, the potential human health effects of new GM foods should always be assessed before they are grown and marketed, and long-termmonitoring must be carried out to catch any possible adverse effects early."
The organisation recommends such evaluations should be widened to include social, cultural and ethical considerations, to help prevent what WHO calls a "genetic divide" between groups ofcountries which do and do not allow the growth, cultivation and marketing of GM products.
"Each country has different prevailing social and economic conditions, and the people have different histories of what they eat and what food means in their society," WHO stated. "Allof these factors can affect how GM foods will be regarded, and taking proper account of these concerns will affect the long-term acceptance or rejection of GM foods and their possible health benefitsand potential risks."
There are now 15 international legally-binding instruments and nonbinding codes of practice addressing aspects of GM organisms. Many developed countries have established specific pre-marketregulatory systems requiring the rigorous case-by-case risk assessment of GM foods prior to their release. Many developing countries lack the capacity to implement a similar system, WHO stated.
In 2004 about 81m hectares of land was being used to grow GM crops by seven million farmers in 18 countries, mainly the US, Argentina, Canada, Brazil, China, Paraguay and South Africa.
The first major GM food was introduced on the market in the mid-1990s and paved the way for the growing of strains of maize, soybeans, rapeseed and cotton. GM varieties of papaya, potato, rice,squash, sugar beet and tomato have been released in certain countries. WHO estimates that at the end of 2004 GM crops covered about four per cent of the total global arable land.
Most of the GMOs commercialised so far in developing countries have been acquired from developed countries and focus on a limited number of traits, mainly herbicide tolerance and insect pestresistance, and crops such as cotton, soybean and maize. Research is also underway on GM seafood and animals.
Many food-processing aids, such as enzymes, produced through the use of GM microorganisms have been on the market for over a decade and are used in a wide variety of processed foods. No live GMfood microorganisms have been introduced onto the market yet, WHO stated.
Current EU requires that all food be tracked and labelled if it contains 0.9 per cent or more traceable GM content, along with derivatives such as paste and ketchup from a GM tomato. Productsderived from GM processing aids, such as GM enzymes or yeast, are not affected. Inciting strong criticism from environmental groups, this year a panel of scientists at the European Food SafetyAuthority (EFSA) cleared a variety of genetic maize known as 1507 for cultivation. Maize 1507 is made jointly by Pioneer Hi-Bred International, a subsidiary of DuPont, and Mycogen seeds, a DowAgroSciences unit.
Biotechnology, in its technical sense, refers to plant and animal farming techniques that alter living organisms to make or modify food products. There are many possible products from transgenicplants, plant parts, and processed foodstuffs, including highly refined substances such as vegetable oil containing little or no detectable transgene-derived protein or DNA.
Under the Cartagena Protocol on Biosafety, governments will signal whether or not they are willing to accept imports of agricultural commodities that include GMOs by communicating their decisionvia an Internet-based Biosafety Clearing House.
