Heart attack rates in Scotland have dropped dramatically in smokers and non-smokers since the country passed a non-smoking law for public places, finds a large study.

Researchers at the University of Glasgow found that heart attacks dropped after the ban by 14 per cent among smokers, 19 per cent among former smokers and 21 per cent among non-smokers.

Before the smoking legislation came into effect, 3,235 patients were admitted to hospitals for heart attacks. Afterward, that number fell 17 per cent to 2,684.

The study tracked heart attacks in nine hospitals in the 10 months before and after a 2006 nationwide ban on smoking in public places that included the workplace as well as bars and restaurants.

Heart attack patients were interviewed about their exposure to smoke, and doctors measured the nicotine levels in their blood.

"What was really exciting from a public health perspective is that the rates of heart attack decreased so significantly in the non-smokers," Dr. Jack Tu, a cardiologist with Sunnybrook Health Sciences Centre in Toronto, told CBC News.

Jill Pell, the study's lead author, said the research highlights the dangers of inhaling second-hand smoke on the part of non-smokers. "They have a disproportionately high risk," she said. "Second-hand smoke has very high levels of toxic gases and small particles."

Doctors say second-hand smoke leads to blood clots, increased heart rate, and high blood pressure, which are all major contributors to heart disease.

The results are welcome news to people like Myra Fairfax, who has waitressed for almost 25 years in a smoke-filled environment. "I used to have to go into the washroom to flush my eyes out just to ease the irritation. It was tough. "

Toronto pub owner John Maxwell has been a vocal opponent of anti-smoking laws. "It seems to me that the solution should be the ban on the manufacturing and sale of cigarettes," he said.

The study is published in the July 31 issue of the New England Journal of Medicine.