Emissions key culprit for smog

BEIJING - A majority of the country's most hazardous airborne pollutants are coming from industrial sources, according to a newly released report by the Institute of Public and Environmental Affairs.

Known as PM2.5 pollutants - hazardous particulates smaller than 2.5 microns - such pollution can travel deep into the lungs and damage people's respiratory systems.

According to the study, China emitted 13.2 million tons of PM2.5 in 2007, among which more than 9 million tons came from industrial sources such as petrochemical plants, cement kilns, and iron and steel smelters.