Almost one year after air pollution in Beijing literally went off the charts, the country’s top research agency, the Chinese Academy of Sciences (CAS), has released a study clearly identifying fossil fuel combustion as the biggest contributor to the deadly smog.
The CAS study, which analyzed air samples in the capital city on a seasonal basis, found that coal burning, industrial pollution and secondary inorganic aerosols — the result of the reactions between different pollutants in the air–– are responsible for 18 percent, 25 percent and 26 percent of the air pollution respectively. These sources, which together account for all fossil fuel combustion emissions, can be thanked for 69 percent of the city’s notorious haze.
The burning of trash, and Beijing’s 5.5 million cars, were found to be responsible for just four percent of the smog.
Keeping cars of the street — an approach the Chinese government has tried in the past — clearly won’t be enough to clear Beijing’s air. Rather, the study indicates a complete overhaul of China’s energy supply is needed. But there are no indications that China is ready to give up coal anytime soon. Last year, China imported more coal than any country in history to feed its ever-growing army of coal-fired power plants, of which there are currently more than 2,300. The latest data show China’s energy mix at 68 percent coal.
In January, Beijing experienced its worst air pollution on record. Levels of particulate matter in the air topped out at 723 micrograms per cubic meter. To put that in perspective, the World Health Organization (WHO) considers 25 or less micrograms per cubic meter ideal for human health. Above 300 is considered hazardous.
Particulate matter (PM) is mostly made up of sulfate, nitrates, ammonia, sodium chloride, carbon, mineral dust and water. PM is classified by the size of the particles, with the smallest particles, PM2.5 considered the most dangerous because they can become lodged deep in people’s lungs. According to the WHO, chronic exposure to particulate matter contributes to the risk of developing cardiovascular and respiratory diseases. PM2.5 was also officially designated as a carcinogen in October.
On the same day CAS released its findings, China’s Vice Minister of Land and Resources, Wang Shiyuan, announced that approximately 3.33 million hectares, or 8 million acres, of China’s farmland is now too polluted to grow crops.