Spending a day here when smog blankets the city and the air pollution is severe is equivalent to smoking 21 cigarettes, or about a pack a day, according to a survey by a company related to the environmental industry.
The results of the survey were carried in the Xinmin Weekly, a Chinese magazine.
Experts are urging the public in China to wear surgical masks because everyone, including children and nonsmokers, are at risk for respiratory problems when severe smog and air pollution settles in over Chinese cities.
In the survey, a high-ranking official at Yuanda Group, a group of companies that operate windmills, among other facilities, measured air quality levels in many cities with the use of monitoring equipment.
The survey found that exposure to the poor air quality levels was comparable to lighting up 25 high-tar cigarettes in Guangzhou, 21 cigarettes in Beijing and nine cigarettes in Shanghai and Nanjing, respectively, if readings taken in these cities on a monitoring day were converted to cigarettes in the tar equivalent.
A professor at Tsinghua University sounded a warning against episodes of high concentrations of PM 2.5, or particulate matter of 2.5 micrometers or less, suspended in the air.
“If the air quality index in the form of PM 2.5 concentration hits 300, it would amount to smoking 20 cigarettes a day,” the professor said.
Particulate matter with a diameter of 2.5 micrometers or less can be inhaled deep into the lungs and absorbed into blood vessels, causing asthma, heart disease and increasing the mortality risk.
In the capital, readings of PM 2.5 topped 300 on at least 15 days in January.