There is considerable literature indicating a link between particulate matter and cardiovascular morbidity and mortality, especially in elderly individuals (Koken, et al, 2003). Particulate matter defined as any particle that measures less than or equal to ten micrometers (< 10µm PM10) or two point five micrometers(< 2.5µm PM2.5) that form from solid particles and liquid droplets. Most particulate matter forms due to vehicle admissions, industrials processes or wood burnings. Additionally, it has also been suggested that ultra fine particulate matter measuring less than or equal to 2.5 µm is considered more harmful to health than are larger particles in aerodynamic diameter because PM2.5 can penetrate deeper into the lung than PM10 (Park, et al, 2010).
Although ambient air pollution has decreased over the past several decades due to stringent air pollution control policies, there has been little evidence directly supporting the extent these control measures have improved public health (Tonne, et al, 2010). Investigative research has observed evidence to support the association of air pollution and particulate matter with increased cardiovascular events.
Further understanding of the mechanisms associated with these observations are necessary. It is important to further examine these associations with more specific end points that may suggest specific pathways (Zanobetti and Schwartz, 2005). The intent of this paper is to present an analytical evaluation of the data in the association of particulate matter and the incidence between cardiovascular morbidity and mortality.
Several reports have addressed the issue of weather and mortality; the factors of extreme temperatures are associated with increased daily mortality in numerous regions of the world (Koken, et al, 2003). Other existing biologic knowledge suggests that air pollution can also trigger electrophysiological disturbances either through an inflammatory mechanism or by the production of mediators that increase blood coagulation (Lee, et al, 2003, Park, et al, 2010, Schneider, et al, 2010). While the majority of the observational studies reported significant effects of cardiovascular events in association with particulate matter concentrations, the timing between a reduction in long-term exposure to air pollution and the possible reduction in the occurrence of cardiovascular events may not be sufficiently long (Tonne, et al, 2010).
More recently, studies have begun to assess the effects of air pollution on cardiovascular health over longer periods. The intent is to deliver more vigorous estimates of health outcomes with greater contrast in changes in air pollution (Tonne, et al, 2010).
While the majority of the studies performed used secondary data sources to compare adverse events with data from air-pollution monitoring stations, two of the studies performed recruited participants to examine results from exposure of particulate matter...