People in Beijing and in as much as a 15% of China are under a blanket of smog. The situation has gotten so bad that people are told to stay indoors with their air cleaners on. They don’t dare venture out without a mask.
Smog in China: Particulate Matter
One of the components of smog is particulate matter (PM). PM is a combination of solids and liquids suspended in the air. Complex organic and inorganic compounds containing sulfate, nitrates, ammonia, sodium chloride, carbon, mineral dust and water make up this dangerous suspension. PM is defined by its size in μm , the fine particulates are called PM2.5 and PM10.
Coarse particles are from 2.5 μm (microns) to 40 μm. Fine particles are from 10μm to 2.5 (PM10) and less than 2.5 μm (PM2.5) in size. PM10 are inhalable, they can penetrate the upper respiratory systems defenses. PM2.5 can travel deep into lungs. To get a grasp of these sizes, there are about 25,000μm to 1 inch and a strand of hair is around 70 micrometers.
In 2005 the World Health Organization (WHO) put out guidelines for these particulates, specifically warning against daily exposure of PM2.5 above 25 μg/m3 and PM10 at 50 μg/m3 .
Recordings of over 400 μg/m3 for PM2.5 have been the norm in Beijing over the past few months.
Associated Health Effects of Smog in China
Recently a prospective study published in the Lancet describes the effects of exposure to particulate matter in cities in Europe. The researchers calculated a hazards ratio for exposures to different size particulates. Using meta-analysis they determined that both PM2.5 and PM10 contributed to lung cancer incidence in Europe.
If that weren’t enough, Lancet published another meta-analysis of studies on air pollution. This study looked at the association of daily exposure to particulate matter and carbon dioxide, nitrogen dioxide and ozone with hospitalizations for heart failure or mortality due to heart failure. This meta-analysis found an association. Finally, exposure to air pollution has been associated with an increase in the number of low birth weight babies in Europe.
“Somewhat similar to a Nuclear Winter”
One scientist, an associate professor in the field of agriculture, stated that China’s agriculture could suffer conditions “somewhat similar to a nuclear winter.”
The smog does not just stay in China. Its impact is being felt in Japan and in the western US. Visible from space, the pollution has been tied to outsourcing of manufacturing from the US to China which has less regulation in a recent study published in the Proceedings of the National Academy of Sciences.
Use of Masks
Dust masks, cotton masks that fit behind the ears are not effective in protecting from the smallest particle size PM2.5. Certification by the National Institutes of Safety and Health (NIOSH) should be printed on the front of the mask. N95 and P100 disposable particulate respirators are recommended and should fit tightly over the face. These are not recommended for children because of poor fit.
What do you think?
What are your thoughts? Do you know the air pollution in your area? To see a real time air quality index visual map click here.
Did you know about the impact air pollution has on health? Did you know your air pollution? Would you wear a mask if you see the air pollution become dangerously high? What level of air pollution would make you wear a mask? Did you know about the link between outsourced manufacturing and air pollution in China?