The air pollution control measures implemented in Beijing during the 2008 Olympic Games - if continued - would reduce their lifetime risk of lung cancer, a new study concludes.
That could translate to 10,000 fewer cases of lung cancer, said the study in the journal Environmental Health Perspectives by researchers from Peking University in Beijing and Oregon State University in the western United States.
The study, among the first to examine how pollution control could impact the health of people in China, focused on pollutants called PAHs (polycyclic aromatic hydrocarbons) that arise from coal-burning, wood stoves and cars.
China emits the most PAHs of any country in the world, followed by India and the United States.
"PAH pollution was definitely reduced by the actions China took during the 2008 Olympics, such as restricting vehicle use, decreasing coal combustion and closing some pollution-emitting factories," said Staci Simonich, an associate professor of chemistry and environmental toxicology at Oregon State University.
"That's a positive step, and it shows that if such steps were continued it could lead to a significant reduction in cancer risk from these types of pollutants."
However, there are more than 3.6 million vehicles in Beijing and the number is rising 13 percent per year.
"Controlling vehicle emissions is key to reducing the inhalation cancer risks due to PAH exposure in Chinese megacities," the study said.
The analysis said that Beijing, home to 22 million people, would see about 21,200 lifetime cases of lung cancer at current levels of PAH pollution.
However if pollution controls instituted during the Olympics were maintained, that number would drop to 11,400.
According to some estimates, 300,000 people die annually in China from heart disease and lung cancer associated with air pollution, including PAHs.
"This is definitely a health concern and one that deserves attention in China by both the government and public," said study co-author Yuling Jia, a postdoctoral research associate at Oregon State University.
Beijing, one of the most polluted cities in the world, has invested $15 billion in improving air quality since 1998, according to the Chinese government. In 2009, Beijing extended some traffic control measures put in place during the Olympics.