Windmills may be an environmentally friendly alternative energy source but they also cause debilitating health problems, say people who live near them.

Wind turbines are popping up in rural communities around the world, including Canada, in the hope that they will reduce reliance on coal and other sources for power. Currently, there are about 1,500 turbines across Canada and there are plans to build another 1,000 to 1,500 in the next year.

But some residents who live near wind farms complain the turbines cause a number of adverse health effects, such as crippling headaches, nose bleeds and a constant ringing in the ears.

Helen and Bill Fraser initially supported the nearby wind farm in Melancthon, Ont. One turbine sat close to the Fraser's kitchen window.

"We thought, more green energy, this is great," Helen told CTV News.

However, Helen says she developed headaches, body aches and she had trouble sleeping. The dog began wetting the floor at night.

"There were nights I was lying in bed and my heart would beat to the pulse of the turbine. It was an uneasy feeling," Helen said.

Ernie Marshall at first supported the wind farm that was placed near his home near Goderich, Ont. However, he also says that once the turbines got rolling, his health began to suffer.

"I had problems with my heart, with my eyes, my digestive system," Marshall told CTV News. "It traumatizes your whole body."

Dr. Nina Pierpont, a pediatrician in upstate New York, has interviewed dozens of people who live near windmills in Canada, the United States and Europe.

Her soon-to-be released book, "Wind Turbine Syndrome," documents the litany of health problems experienced by some people who have wind farms near their homes.

Pierpont believes that with the growth of wind farms near residential areas, Wind Turbine Syndrome "likely will become an industrial plague," she states on her website.

Scientists have only begun studying the phenomenon. Some early findings suggest that wind turbines create a high intensity, low frequency sound that may have an effect on the body. Not only can the sound potentially cause debilitating illness, some researchers believe the vibrations the sound causes in the inner ear may lead to vibro-acoustic disease. That can cause dizziness, nausea and sleep disturbances.

However, officials with the Canadian Wind Energy Association point to a handful of studies they say prove that windmills lead to few, if any, adverse health effects.

"We know there have been complaints about health impacts of wind turbines," Sean Whittaker of the Canadian Wind Energy Association told CTV News.

"On the other hand, we know there are some 10,000 turbines installed across North America and complaints have been relatively few. There's been research done on this and to date, that research has come to a fairly solid conclusion that wind turbines do not have an adverse impact on human health."

Whittaker says the windmill industry follows all regulations for where and how a wind farm can be established.

"It's important to point out that in order to install a wind farm, there is a very lengthy procedure to go through of environmental assessments, approvals, permits, regulatory approval," Whittaker said. "And those are skewed around making sure the turbines don't have an effect on people, on plants, animals, birds."

The issue has not just put experts at odds. Communities across North America are divided between residents who say local windmills have made them sick and their neighbours who don't believe them.

"Everyone was calling me a liar," Ernie Marshall said. "It don't matter who you talk to. You bring 'em out here and they'll say that noise don't bother us. Sit there for a week under that and listen to it and see what it does to your body."

The inconsistencies in the early research, coupled with the fact that some residents who live near wind turbines complain of such a wide array of symptoms, are evidence that further study is needed to determine if Wind Turbine Syndrome is a problem, how big of one and what should be done, experts say.

"Depending on your distance you'll have 30, 40, 50 per cent of people who are troubled, but not 100 per cent," Dr. Robert McMurtry of the University of Western Ontario told CTV News.

"That's why it's important to do these studies to see just how many are troubled and how real it is."

More research will also help governments determine a standard distance that windmills should be located from homes and schools.

For now, provincial governments are setting their own guidelines, which call for windmills to sit about 400 metres from buildings.

Some groups, including the National Academy of Medicine in France, suggest larger setbacks between 1.5 and two kilometres away from homes and schools.

Some affected residents can only sell their homes and move away. The Frasers left their home of 32 years and moved to nearby Shelburne, Ont. They say their symptoms have, for the most part, vanished.

Ernie Marshall moved to the town of Seaforth, Ont., which is several kilometres away from the turbines near his former home.

"I had to get out or I wouldn't be standing here talking to you," Marshall said.

With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip