Shanghai and Beijing are among a number of major Chinese cities which experienced “hazy” days for up to half of last year.
The findings indicate China’s worsening trend of urban air pollution, which could be blamed mainly on emissions, according to the state environmental watchdog.
The other cities experiencing haze for periods from a total of three to six months last year included Guangzhou, Shenzhen, Nanjing, Suzhou and Tianjin.
Even if China continues with its current Five-Year Plan efforts to reduce emissions it would still take 10 years for air quality in Chinese cities to return to the cleaner levels of 2005, an unnamed official with the Ministry of Environmental Protection told the Economic Information Daily.
Shanghai experienced “dusty haze” conditions for about 155 days on average during recent years, according to the city’s meteorological bureau. Haze was most frequent during the three months from November.
Beijing saw a significant increase in the number of hazy days this autumn compared to previous years. Weather experts concluded the rise had a direct connection with heavier air pollution, in particular, harmful polluting particulates smaller in diameter than 2.5 microns (PM2.5).
Such particulates are produced by automobile emissions, industrial manufacturing, coal burning and treatments of mineral materials. Health experts say they pose major health risks as they are small enough to lodge deep into the lungs and even enter the bloodstream leading to premature death and long-term diseases.
Chinese cities currently adopt the less sensitive PM10 standard in reporting air quality. The practice could lead to the underrating of air pollution or even reporting air quality as “fairly good” when it would have been rated “heavily polluted” under the PM2.5 standard, experts said.
“The increase in PM2.5 particulates is the major cause that worsens air pollution. During fog, the air becomes more difficult to dilute. So polluting substances carried by the micro particulates gather in the air, causing sick feelings to people’s respiratory systems,” said Yan Gang, an environmental ministry expert.
Application of the PM 2.5 standard has been added to the latest draft of a future regulation that watchdogs must follow in reporting air quality.
But any new regulation would not come into effect before 2016, according to the current scheme by the ministry.
City residents across the country have been urging environmental authorities to improve monitoring facilities and adopt the PM2.5 standard and doctors have said that if there were more effective warnings about air pollution, people could take better precautions.
Nearly 40 percent of major cities, including Beijing, had air pollution exceeding the country’s official limits during the first six months of this year, according to the ministry.
Shanghai was among the other 60 percent of Chinese cities reaching the national “fair quality” air standard but the city still saw a 25 percent increase in particulates under the PM10 standard.