Fine Particulate Air Pollution and Hospital Admission for Cardiovascular and Respiratory Diseases

Abstract

Numerous epidemiological studies have shown associations of acute and chronic exposures to airborne particles with risk for adverse effects on morbidity and mortality.^1,2 The recent evidence on adverse effects of particulate air pollution on public health has led to more stringent standards for levels of particulate matter in outdoor air in the United States and in other countries. In 1997, the US National Ambient Air Quality Standard for airborne particulate matter was revised, maintaining the previous indicator of particulate matter of less than or equal to 10 μm in aerodynamic diameter (PM₁₀) and creating a new indicator for fine particulate matter of less than or equal to 2.5 μm in aerodynamic diameter (PM_2.5).³ Following the implementation of the PM_2.5 National Ambient Air Quality Standard, a nationwide monitoring system of this pollutant was implemented. Data on PM_2.5 are now available for many parts of the United States starting from 1999 through the present.