THE unknown environmental impact of genetically-modified crops and their effect on organic farming were the main concerns of York residents at a GM debate in the city.

Last night about 80 people gathered at the Priory Street Centre, to debate the pros and cons of GM foods, with the effect on the environment the main area of concern.

The debate came a week after City of York Council agreed to become a "GM-free zone" by taking all possible action to remove GM foods, crops or animal feeds from any areas under its control.

At the debate Dr Julian Little, of Bayer CropScience, spoke in favour of GM, with Dr Sue Mayer, director of GeneWatch and member of the Agricultural and Environmental Biotechnology Commission, speaking against.

Dr Mayer said there was no significant benefit to GM crops.

She said: "Our position is that at the moment, under the terms and conditions that we have got and with the crops on offer, we should say 'No thank-you' to GM.

"There's no proper rules on liability so if something went wrong and the environment was harmed, we wouldn't be able to go to the industry to get payment for that.

"The insurance industry won't cover those costs anyway so it tells you something about the nature of the risks.

"There are no real obvious benefits. There seems to be no real market or appetite for GM crops.

"There could be some advantages for very big farmers, whether that justifies the potential risks.

"We have got other ways of producing healthy food. We should be investing in those, not just GM."

But Dr Little said that GM offered consumers choice - and the popularity of GM products could only be measured if the products were widely available.

He said: "I appreciate that people have worries. But, when it comes down to it, choice works both ways.

"To really understand whether people actually want to buy something you actually have to put it on the market.

"The last time something was on the market - tomato paste - it outsold the supermarket's own brand.

"It was clearly labelled as GM, but it was withdrawn after a couple of years after pressure.

"At the present time people don't have that choice."

Dr Little said GM offered an opportunity to increase the nutritional value of foods, to allow reduced use of pesticides and to reduce crop waste, therefore reducing price.

Coun Andrew Waller, City of York Council executive member for environment and sustainability, who chaired the debate, said he was pleased with the public response.

The public feedback will this week be collated and sent to the Government as part of a national consultation on the GM issue.

Updated: 10:49 Wednesday, July 16, 2003