Smoking in city streets not only significantly increases air pollution, but can can trigger lung cancer in passers by, a new study shows.
A University of Otago study measured the quality of air in the city streets of Wellington over five weeks, specifically when smokers exhaled.
"The study found actually the presence of smoking nearby increased the air pollution level by 70% in these fine particulates," said Professor Nick Wilson.
Wilson used a special air monitor that sucks in the second hand smoke and measures the amount of soot particles.
The study found when smokers were observed at an average distance of more than two metres, the pollution level was 16 times more than the background level.
"People are spending time walking around the city so it is contributing to the background risk of lung disease and a preventable risk," Wilson said.
The professor hoped central governments would help to reduce the risk of second hand smokers developing lung cancer through imposing bans on smoking in public areas.
Wellington City sports parks and playgrounds are to become smokefree areas, as the Council moves to support the Government's goal of making New Zealand smokefree by 2025.
Auckland's 40,000 hectares of regional parks are smokefree. A report has also been proposed to the Auckland Council to ban smoking in town centres, pedestrian malls and at council-run events.