FARMERS are being asked to take care with pesticides after water in the River Cherwell was found unfit to drink.

Tests carried out by the Environment Agency revealed that water in the river at Banbury did not meet drinking standards.

The cause of the pollution is thought to be chemicals being washed off farmland, and farmers in the area are being offered guidance on the use of fertilisers and pest sprays.

John Archer, environment and land use advisor for the National Farmers' Union, said: "Farmers always co-operate when things like this happen.

"The use of pesticides is controlled by strict regulations and the river pollution is not from one source but small amounts of chemicals from many sources.

"The Environment Agency has decided that pollution in the Cherwell is high enough for something to be done. We are not sure why levels are so high in the Banbury area and we will do what we can to improve the situation."

The problem is described as "not serious or illegal" because the water is filtered and treated before it reaches household taps.

But farmers have been invited to a meeting this week at which environment officers will point out the dangers and financial effects of water pollution.

The meeting is part of a campaign started in November last year when landowners were asked to take more care with chemicals in a bid to reduce water purification costs.

The Upper Cherwell Land Care Project was part of a national scheme set up by the Department for the Environment, Food, and Rural Affairs to tackle water pollution.

Environment minister Ian Pearson, who launched the project, estimated that the cost of removing harmful pesticides and nitrates from drinking water was £7 a year for every water customer.

Jo Old, from the Environment Agency, said: "The local aim is to raise awareness of issues in the Cherwell catchment area.

"We want to emphasise the link between land and water in improving water quality and to assist farmers in tackling pollution."

Barbara Young, chief executive of the Environment Agency, added: "This is an important initiative. It supports simple, low-cost activities that could make a big difference to our environment.

"We hope farmers and land managers grasp this opportunity to show how we can work together to improve water quality."