It's amazing. The truth is that GM foods are in fact safer than non-GM foods, and cause less damage to the environment than non-GM foods.

What's the difference between conventional food and GM crops?

For centuries, farmers have modified crops by selecting seeds that give the best yield, taste and nutrition.

To get those seeds, breeders cross and backcross different varieties of a plant, thus mixing thousands of unknown genes with largely unpredictable results. Then they wait a full growing season. If the right hybrid doesn't turn up, they repeat the trial-and-error process.

GM techniques let plant breeders choose the traits they want with much greater precision. A specific gene among the 50,000 in, for example, a tomato can be isolated and transferred directly to another plant to obtain desirable traits like pest resistance or better quality. This does not harm the nutritional or health aspects of the target plant.

Greenpeace and other such groups assert that GM techniques pose special risks not created by traditional plant breeding. This assertion is not supported by scientific evidence. "In every study so far, no evidence has been found that GM crops present special risks," notes R. James Cook, professor of plant pathology at Washington State University and a member of America's National Academy of Sciences. "The types of risk are exactly the same as for crops modified by the classical plant-breeding methods."

Has testing been done to ensure safety for humans?

Scientists note that the GM foods available today have been put through more testing than any food in history. Around the world, some 25,000 field trials have been done on more than 60 crops in 45 countries, including most of the 15 countries of the EU.

Before being approved for use, GM foods are assessed for "substantial equivalence" under guidelines issued by the World Health Organization, the Food and Agriculture Organization, the Organization for Economic Co-operation and Development, and Europe's Novel Foods Regulation, among others.

This means scientists have compared them with their traditional counterparts and found them no different in nutritional value and health properties. Says Maurice Lex of the European Commission's Biotechnology Unit in Brussels: "We've spent 43 million euros on biotech safety since 1986. It's total nonsense to claim, as some do, that safety studies on GMOs haven't been done."

If a gene were transferred from the peanut plant to, say, the carrot, that could cause a reaction in someone allergic to peanuts who thought he was only eating a carrot. So GM foods undergo rigorous testing for potential allergy problems. Similarly, pesticides bred into crops like Bt corn are not believed to affect humans, unlike widely used conventional pesticides that can cause muscular and nervous-system symptoms if accidentally consumed.

Says Maurice Hofnung, head of the Pasteur Institute's molecular programming and genetic toxicology unit in Paris: "We've never had the least incident with GMOs -- not a single incident in 25 years of research and use. So, if the guidelines are followed, I conclude it's safe."

Why is biotech agriculture needed?

Nearly 40 percent of the world's food crop is lost every year to insects, fungal diseases and spoilage that biotech could help prevent. Nutrition experts say GM crops are also going to be needed to help increase cereal yields to meet food demand, especially in the Third World. Dr. Manvendra Kachole, a leader of Indian farmers' unions, recently lashed out at anti-GMO activists: "India today cannot afford to listen to pseudoscientific rhetoric."

On the biotech horizon are crops that require less pesticide and water during the growing season and that have improved nutritional content. One GM rice in development at the Swiss Federal Institute of Technology in Zurich has enough beta-carotene to satisfy daily vitamin A requirements with only 300 grams of cooked rice -- a boon to the up to 250 million people around the world who suffer serious vitamin A deficiency. The same rice has increased iron and will help fight the deficiency of this mineral, which affects over four billion people.

Danish researchers are working on GM cassava that can be eaten without danger of goiter and leg paralysis even if not properly cooked, unlike the variety consumed by more than 400 million people, mostly in the developing world.

Are GMOs safe for the environment?

Most scientists point out that no new ecological or environmental problems have shown up in the thousands of biotech field trials and the millions of hectares of commercial planting. In fact, all the signs point to less damage to the environment than with conventional crops. A study by the National Centre for Food and Agricultural Policy in the United States last year showed that planting GM corn with the Bt gene that kills the corn borer insect reduced the amount of land that would have been sprayed with traditional insecticides by 810,000 hectares. That's millions of litres of chemicals that didn't seep into groundwater.

GM crops resistant to herbicides while growing, rather than treating the soil before planting, may also reduce the number of chemical applications needed. The herbicides used with these GMOs may be less polluting than conventional ones like atrazine, according to Bill French at the National Institute of Agricultural Botany in Cambridge, England.

Increasingly, environmental scientists are coming to realize that Europe's intensive conventional agriculture has raped the countryside in a way GM crops never could. Three decades of it have poisoned groundwater and created dozens of "superweeds" with tolerance to herbicides. In the United Kingdom alone, the last 20 years have seen the loss of more than 20 million farmland birds of ten species.

"In Europe we already have serious problems with conventional agriculture, including surface and groundwater pollution," says Brian Johnson of English Nature, the government's official advisors on nature conservation. "Biotechnology may offer a way out."