Alarming new results from official trials of GM crops are severely jeopardizing Government plans for growing them commercially in Britain.

The results, in a new Government report, show – for the first time in Britain – that genes from GM crops are interbreeding on a large scale with conventional ones, and also with weeds.

The report is so devastating to the Government's case for GM crops that ministers last week sought to bury it by slipping the first information on it out on the website of the Department of the Environment, Food and Rural Affairs (Defra) on Christmas Eve, the one day in the year when no newspapers are being prepared.

Even then, the department published only a heavily edited summary of the main report. Unusually, the full report, which will contain much more devastating detail, was withheld from publication on the website. Defra said it was available on request, but when The Independent on Sunday tried to ask for it last week, the department said no one was available to provide it.

The report, the result of six years of monitoring of GM crops in Britain, is particularly politically explosive and it gives the first results from the official farm-scale trials, which ministers have been running to test the suitability of growing GM crops in Britain.

The Government has repeatedly said that the results of the trials would settle the question of whether GM crops endangered the environment but – perhaps because it knew what the research had found – it has been downplaying their significance in recent weeks.

The trials – originally set up to buy time in the face of strong public hostility to the crops – were not designed to look at the possibility of genes from GM crops contaminating nearby plants, but focused on the effects of different uses of pesticides on GM and non-GM plants. But, after this was criticized, studies of this "gene flow'' were bolted on.

The report covers true studies carried out between 1994 and 2000 by the National Institute of Agricultural Botany and the Laboratory of the Government Chemist. It shows that genes from GM oil seed rape, specially engineered to be resistant to herbicides, contaminated conventional crops as far as 200 yards away.

Equally alarmingly, GM oil seed rape that escaped from a crop harvested in 1996 persisted for at least four years, until studies ended in 2000.

In another case, the report adds: "It was found that some combine harvesters were not cleaned after the harvesting of the GM crop,'' and "subsequently flushed out'' the GM seed on to ground intended for conventional crops "causing contamination of this field.''

Most worryingly of all, the report shows that the GM crop readily interbred with a weed, wild turnip, giving it resistance to herbicides and thus raising the prospect of the development of "super weeds".

The report concludes that the research "indicates that commercial-scale releases of GM oil seed rape in future could pollinate other crops and wild turnip''.

Other studies from elsewhere in the world have shown that interbreeding occurs, and English Nature, the Government's wildlife watchdog, has said super weeds will "inevitably'' emerge in Britain if GM crops are grown commercially.

In a commentary also published by Defra on Christmas Eve, the official advisory committee on releases to the environment said that the contamination was "entirely within expectations''.

The committee added that "in itself'' gene flow did not constitute a risk to the environment. But Pete Riley of Friends of the Earth said the results showed that if GM crops became widespread, almost all similar crops would inevitably become contaminated, severely threatening organic agriculture. He added: "It is not surprising that the Government has tried to cover up this report.

"It shows that we need to know a great deal more about these issues before we even contemplate growing GM crops commercially.''

© 2002 Independent Digital (UK) Ltd

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