Despite these efforts, levels of coarse particular matter were higher than considered safe by the World Health Organization 81 percent of the time during the Beijing Olympics. They reached unacceptable levels 100 percent of the time for the most dangerous particulate matter (smaller than 2.5 microns), which is more easily inhaled into the lungs and causes more serious health problems. Levels of the smaller, most harmful particulate matter was also the least affected by government efforts to reduce pollution output, the study concluded.
The finding of levels of pollution higher than those announced previously by Chinese officials reflects a difference in measurement methodology, researchers said, although the approaches used in this study have been widely accepted for many years.
The studies were initially prompted due to traditionally high levels of air pollution in Beijing and the potential risk they posed to athletes and spectators, Simonich said. The city of 17 million people is surrounded by mountains in several directions that trap air pollutants, and has faced significant increases in particulate air pollution in recent years due to increasing industrialization, numbers of automobiles, coal and biomass burning, and other causes.
Atmospheric particulate matter, researchers say, is a concern because various sized particles have potentially toxic chemicals "sorbed" to them. The fine particles have been linked to increased respiratory morbidity a
'/>"/>
| Contact: Staci Simonich staci.simonich@oregonstate.edu 541-737-9194 Oregon State University Source:Eurekalert |