Home cooking fires, traffic tagged as pollution sources in China

Home cooking fires and city traffic emissions create 80 percent of the air pollution in China that spreads over large areas of East Asia, researchers say. Home cooking with coal briquettes and byproducts of fossil-fuel combustion in vehicles is impacting human health and fostering global warming, a study reported in the journal Environmental Science & Technology concludes. Orjan Gustafsson of Stockholm University and colleagues from China, South Korea and the United States note in their study the exact sources of soot, or "black carbon," air pollution in the People's Republic of China has up to now been uncertain. A powerful carbon-14 identification method was used to trace fully four-fifths of the black carbon emitted in China to incomplete combustion of fossil fuel such as coal briquettes used in home cook stoves and automobile and truck exhaust, they reported. Tiny particles of black soot can be inhaled deep into the lungs, and estimates implicate soot with 500,000 premature deaths annually in China alone, the said. Black carbon in the atmosphere also absorbs sunlight, and many scientists say they believe soot is second only to carbon dioxide as a factor in global warming. "To mitigate near-term climate effects and improve air quality in East Asia, activities such as residential coal combustion and city traffic should be targeted," the researchers wrote.