Researchers outlined the environmental risks that are associated with genetically modified food and the reaction to its arrival before describing the way forward.
Scientists should concentrate on evaluating the environmental risks connected with specific genetically modified crops rather than making general comments on the technology, said Alan Gray of the Institute of Terrestrial Ecology near Wareham in Dorset.
Crops such as maize and tomatoes have no wild relatives in the United Kingdom, he said - this means that they cannot pass on any foreign genes by breeding with native species. Carrots and plums, however, do have wild relatives and could breed with these to produce hybrid plants with the foreign genes.
Because most people do not recognise these differences, scientists often have to respond ambiguously to general questions. "In my view," Professor Gray said, "the debate about genetically modified organisms has been too much in the realm of Plato - broad ideas and generalisations - and not enough in that of Aristotle - detailed fact, logical and analytic."
If genetically modified crops were able to establish a persistent, feral population, this would be a threat to the environment, Professor Gray said.
For example, rogue oil seed rape plants can be seen on the verges of roads and in fields set aside from cultivation. However, the plants must be disturbed regularly -Jby ploughing, for example - in order for the population to be robust enough to survive. A single genetically engineered oil seed rape in isolation could not become a serious weed, Professor Gray said.
He is conducting a series of studies to identify which genetically modified crops would present the greatest threat to the environment. But he opposes calls for a moratorium on releasing genetically modified crops because it is too broad. "It is like saying that we would stop all vaccinations if there were problems with the measles vaccine," he said.
Peter Lillford of Unilever Research in Colworth pointed out that the attitudes of researchers to genetically modified crops may be different from those of farmers, manufacturers, retailers and consumers. "You donot have to be a genetic engineer to understand the significance of genetic engineering and its impact on food."
Professor Lillford would like to open the debate on genetically modified crops to identify specific areas of conflict that can be addressed.
"It is useful to understand the interests and aspirations of each element of the food chain and hence achieve a compromise between interests," he said. "We all have to behave like grown-ups and stimulate debate."
He has welcomed the government's initiative in setting up a public consultation on developments in the biosciences.
The initiative aims to find out what the public knows about how biotechnology is controlled, how well the regulations work in the public's view and whether the regulations need to be changed.
Lynn Frewer, a psychologist at the Institute of Food Research near Reading, argues that the government should be more open about how it makes decisions on issues such as whether to cultivate genetically modified crops.
After interviewing about 900 people, Dr Frewer concluded that people do not trust information provided by the government and prefer to rely on that issued by consumers' bodies and medical doctors. "Consumers' organisations were seen to have more concerns about welfare; they did not sensationalise information and they did not conceal information," Dr Frewer said.
"The public perceived government and industry as supporting their own agendas," Dr Frewer added. They were also thought to be more defensive in their presentation of facts.
To improve trust in the government, people must become involved in the decision-making process, Dr Frewer said.
This can be achieved through initiatives such as consensus conferences, public representation on decision-making bodies and public debate, she added. The public consultation on developments in the biosciences could be a crucial first step.