Ministers are being urged to order a moratorium on the construction of new windfarms after peers warned that possible health risks had not been properly investigated.

The call came after a study by Plymouth GP Dr Amanda Harry which highlighted serious health effects on people living near the Bears Down windfarm near Padstow in Cornwall.

Conservative peer Lord Dixon-Smith urged ministers to investigate the study, which showed that 93 per cent of people living close to wind turbines reported that their lives had been "adversely affected", with some moving house to get away from the problem.

Dr Harry said it was clear that low-frequency noise generated by windfarms caused "extreme distress" to some people, with symptoms ranging from headaches and sleep disturbance to nausea and dizziness. She said yesterday she would be writing to ministers appealing to them for "more information and new and independent research".

Lord Dixon-Smith said Denmark had already ceased building new wind farms, "in part as a consequence of health concerns", and the Department for Environment, Food and Rural Affairs had commissioned an investigation into the health effects of low-frequency sound.

"Does that not suggest at the very least that the Government should consider a moratorium on further construction until the matter is properly cleared up?" he asked. But Science Minister Lord Sainsbury dismissed the call, saying the health effects of windfarms were considered to be "non-existent at this stage".

The South West has been earmarked for around 250 giant turbines - the equivalent of 1,000 of existing machinery - and fears are growing that the health problems could multiply. Dr Harry expects that more and more doctors will soon be treating people suffering side-effects from windfarm noise.

But Lord Sainsbury said a study in 1997 had cleared windfarms of causing health damage, and the Government was not aware of any "scientifically validated evidence" to the contrary.

He added: "The study by Dr Harry, which suggested that low-frequency noise from windfarms could have an effect on human health, is contradicted by the study in 1997, which showed that vibrations from wind farms have no impact on low-frequency vibration levels at the distances we are talking of."

He said Denmark's decision to site more windfarms at sea was for efficiency reasons rather than health concerns.

Conservative peer Earl Attlee asked what the Government considered a "safe separation" distance between windfarms and dwellings. Lord Sainsbury said guidance ranged from 300-400m, but conceded that some operators, like National Wind Power, had a "more stringent" guideline of 600m, which was "probably desirable, but not necessary".

Lib-Dem Lord Watson of Richmond urged ministers to examine "well-documented" Spanish research about damage caused to birdlife by some windfarms.

Lord Sainsbury described the possible threat to birdlife as "an issue of the greatest importance", adding: "We are very aware of it." But he rejected calls from Conservative peer the Earl of Liverpool to invest more time and money on the potential of tidal power rather than on "controversial" windfarms.

Lord Sainsbury said: "Tidal power is extremely expensive at this stage compared to wind turbines, which are by far the most economical option.

"There is no kind of energy generation that does not have some downsides. The question is therefore to balance the risks, the costs and the energy security objectives. The health downsides of wind turbines, as I hope I have pointed out, are non-existent at this stage."

Dr Harry said yesterday that Lord Sainsbury had based his response on out-of-date, seven-year-old research. "At that time even the people who did the study said it should be reviewed on an annual basis, and it hasn't been. They accepted that with the new generation of much bigger turbines it should be re-examined," she said.

"We need more information, new and independent research. How does he explain away the fact that people who live next to windfarms say it affects their health, they are suffering big problems and it's happening all over the country? How can he say that when they are complaining and making an issue of it?"