Today we review some leading edge research into the make-up of particulate pollution from the aspect of what associated chemicals are found with PM 2.5 and how do they affect their impact on human health. Results indicate higher concentrations of PM 2.5 in winter than summer when rain cleans the atmosphere and higher in late morning and evening because of vehicle emissions. Magnesium (Mg) was found to increase mortality rates at least in South Korea where the data were gathered.
Key Quotes:
“The chemical characteristics of Seoul’s PM2.5 were more similar to Western U.S. PM2.5 than the Eastern U.S. PM2.5 with lower SO4 contributions and higher NO3 contributions, although overall PM2.5 levels were much higher”
“Several components that were among the largest contributors to PM2.5 total mass (NO3, SO4, and NH4) were moderately associated with same-day cardiovascular mortality at the p<0.10 level”
“observed significant positive associations between several components (e.g., Mg, NH4, and NO3) and cause-specific mortality in Seoul, Korea”
“The higher PM2.5 concentrations in winter are likely due to increased emissions (from combustion sources for heating) and a lower mixing height The lower concentrations of PM2.5 in summer may relate to the large amounts of wet deposition as a function of precipitation, which is the major process of particle removal from the atmosphere, with 49% of the year’s deposition in this season”
“PM2.5 mass and some components (e.g., OC, EC, NO3, and NH4) showed similar patterns of daily concentrations, with peaks in late morning and evening. The peak started to form in the early morning or evening, attributed to the heavy traffic and increased several hours later”
“We found significant positive association between Mg and total mortality… Likewise, secondary products of fuel combustion (NO3, SO4, and NH4) exhibited the stronger associations with cardiovascular mortality than did other components”
Related articles
- Health Impact of Exposure to Particulate Matter in Beijing, China (pollutionfreecities.blogspot.com)
- More Dangers Related To Toxic Dusts (futureenv.blogspot.com)
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