The Pesticide Action Network (PAN) believes tighter safeguards are needed.

Alison Craig, a PAN spokeswoman told the BBC that the group was aware of cases where people had been made very ill by pesticides.

Damaged health

A woman in her fifties from Lincolnshire has the immune disease lupus. She says her symptoms have been exacerbated by exposure to pesticides A famer has been prosecuted for over-spraying in a ditch next to her house

She said five million people lived in rural areas in the UK, of which at least 250,000 lived in houses next to farmland that was intensively sprayed.

"We are absolutely certain that pesticide spraying causes health problems - some people's lives have been ruined.

"There may also be long term health effects across a much wider population.

"Not enough data has been collected, and the Health and Safety Executive's current system for collecting this data is deeply flawed."

Ms Craig said houses should be protected by buffer zones where spraying is banned.

In addition, walkers should be notified of when spraying has occured, and what has been sprayed.

Options under consideration

Damaged health

Tessa Lawton and her son, from Lamberhurst, Kent, suffered symptoms, including breathlessness, nausea, headaches and puffiness around the face Her GP told her other people in the same area had reported similar problems

Professor David Coggan, chairman of the independent Advisory Committee on Pesticides (ACP), said there were issues that had to be examined.

He said various initiatives were under consideration, including warning signs, buffer zones and restrictions on the use of certain pesticides.

However, he said: "Before you introduce those you need to be reasonably confident that they are actually going to produce benefit, and that they are workable.

"There is no point in introducing a bureaucratic system that does not actually work."

Professor Coggan said a rigorous risk assessment was already in place.

The issue will be discussed at the ACP open meeting in York on Wednesday.