Gardeners are being warned not to grow vegetables after fears that their allotments may be polluted.

Water has been found to contain chemicals that may have originated from rotting household refuse in the Claypits allotments, off London Road, Bicester.

About two dozen allotment holders are being called to a meeting by Cherwell District Council and Bicester Town Council next Tuesday. They will be advised not to grow root vegetables but they can continue to grow flowers.

Chemicals were found in water running off the allotments and neighbouring scrubland when preparatory work was being carried out on the nearby Oxfordshire County Council highways depot, which is going to be used for housing.

Cherwell's head of environmental services, Eileen Edwards, said: "There is no evidence at present suggesting any risk to public health.

"The ammonias, chloride and sulphates found were slightly higher than World Health Organisation guidelines on chemicals in water.

"For safety reasons, it was decided to take soil samples from the allotments. If necessary, some remedial work will be undertaken."

One allotment holder, Marjorie Ralph, who lives in nearby Alchester Terrace, said: "I have been gardening there for 32 years. I took over when my father died. I grow all the vegetables I need and have never had any problems with them. The soil there is variable."

Another holder, David Austin, of Woodfield Road, said: "I am concerned about the contamination. I have found it good soil because it was household refuse years ago when rubbish was more environmentally friendly than today.

"Several of us were just ready to put seeds in for the new season. I hope this is not a ruse to get us off the allotments so the land can be used for housing."

Council officials have denied suggestions that remedial work is a ruse.

Mrs Edwards refuted suggestions that the allotments would be built on. She did say that a nearby badgers sett might have to be moved, but this could only be done with the permission of English Nature.

Mrs Edwards added: "It might be that we can do the remedial work without disturbing the badgers."