Barbara Sumner Burstyn: Unresolved issues in GM debate leave potential for disaster

I love a finely tuned argument, a sound justification or a well-debated issue. I've even been known to swap sides in response to new information or a reasoned defence.

So when I read about the first crops of genetically modified potatoes planned for planting after October when New Zealand's GM moratorium is lifted, I was at first dismissive. But by the end of the article, ably reported for the Herald by Simon Collins, I was almost convinced.

First, there's the pesticide argument. Genetically modified crops, in this case Bt (bacillus thuringiensis) infected potatoes will be resistant to alien invaders, allowing farmers to cut back on pesticide. In fact, biological controls will increasingly replace chemicals to control all manner of pests and diseases.

That argument worked for me. After all, with around 3300 tonnes of pesticides finding their way into our ecosystem annually, anything that reduces them has to be a plus.

Then there's the productivity angle. GM crops will produce more for less effort. Or as Lincoln University's Dr Colin Eady, from Crop and Food Research, puts it, genetic modification allows for the production of safe, sustainable and efficient food supplies.

Eady, who seems typical of New Zealand scientists, says his motivation comes from a desire to reduce the harm done to the environment. He believes his vision is complementary with a green viewpoint.

I see the virtue of a world in which biotechnology, and not poisons, is used to specifically deal with pests and disease - a world that can provide plentiful nutritious and varied food with reduced impact on natural environments and free of poisons like 1080, varroa mites and painted apple moths; a world without possums; and, most especially, a world able to deal with the problems of famine.

But ask Dr Suman Sahai about resolving famine through genetically modified organisms (GMOs) and she's dismissive. Dr Sahai is part of the Gene Campaign in India, an organisation dedicated to protecting genetic resources, strengthening self-reliance in agriculture and sustainable food production.

According to Dr Sahai, the first commercial Bt cotton in India, grown under normal local conditions, either did poorly or failed altogether. Even so, a report published in the reputable journal Science hailed the crop a huge success.

Now here's the really disturbing part. The article, which is being widely quoted, is based exclusively on data supplied by the company that owns the Bt cotton, Mahyco Monsanto. To make it worse, the figures were based on a few selected trial plots belonging to the company, not farmers' fields.

But it's not only India. The antipathy to GM foods is spreading to other Third World countries.

Last year Zambia refused 63,000 tonnes of GM corn from the United States.

And across Africa there's a growing concern that the US is taking advantage of famines to dump genetically modified foods on starving populations, which, in turn, depresses prices and destroys local markets

Then there's the issue of the growing importance of organic produce. Even though our own scientists want to believe they share the green agenda, the organic brigade does not agree.

In short, with worldwide demand for organic produce rising at about 10 per cent a year, European consumers are rejecting GM food as if it were the plague.

The American response to consumer rejection of GM is to blame tightened European labelling laws for fuelling fear. In fact, Americans, just like people in Africa and Europe, want to be able to make informed choices about what they eat.

In February a collaborative study by 12 US universities found that 93 per cent of Americans wanted GM food labelling.

But under present regulations it's an offence to label food as genetically modified.

That's because US food law recognises only outcome and not process - so a tomato is a tomato no matter its composition or how it's grown.

There are many other areas of concern, from contamination of non-GM crops and lack of compensation for the contaminated - in New Zealand as in the US - to the compromising involvement of agribusiness in pushing for and controlling the development of GM products and markets, to fundamental concerns about GM safety.

For example, new research just in by scientists at Imperial College London and the Universidad Simon Rodrigues in Caracas, Venezuela, has found that Bt, the same naturally occurring poison that New Zealand scientists are preparing to insert into potatoes - seems to be acting as a "supplementary food protein", nourishing the pests they have been specially engineered to kill.

According to the research, one of the key benefits of GM - crops that come equipped with their own pesticide - is being radically undermined, striking at the heart of genetic engineering in agriculture. The report also suggests an even greater threat to organic farming than has been envisaged.

Pete Riley, a spokesman for Friends of the Earth, said: "If we'd come up with the suggestion that crops engineered to kill pests could make them bigger and healthier instead, we'd have been laughed out of court."

Given all the loose ends of this debate and the safety and moral implications of the development and use of GM, you have to ask why New Zealand, a small, perfectly formed country, isolated in the middle of the South Pacific, is rushing to embrace a technology that has the potential to destroy its most compelling international advantage - being GM-free.