- Average exposure of the general public to particulate matter of 2.5 microns or less in size (PM2.5).
Air Pollution is the fine particulates in the air we breathe. It is the population-weighted average exposure to particulates 2.5 micron and smaller. Air pollution is monitored in many counties where population density is significant and/or where there have been pollution concerns in prior years. Population weighting of the exposure data adjusts the information to reflect the number of people potentially exposed to particulates. In counties where exposure data is available, exposure is considered to be uniform throughout the county. Where county data is not available, the population was assumed to be exposed to the background level of particulates in the air quality control region and/or state. Background levels are estimated to be the average of the lowest measures in each region or state for each of the last 3 years. The 2015 ranks are based on 2012 to 2014 data from the Environmental Protection Agency.
Air pollution varies from a low of 5.0 micrograms of fine particulate per cubic meter in Wyoming to 12.5 micrograms of fine particulate per cubic meter in California. The national average is 9.5 micrograms of fine particulate per cubic meter, down slightly from 9.9 micrograms in the 2014 Edition and down significantly from 12.2 micrograms in the 2008 Edition.
Public Health Impact
Air pollution is an important aspect of the physical environment that impacts health. Air pollution is widespread, affects a large number of people, and can have severe health effects, especially on young children and older adults., Fine particulates in smoke or haze can penetrate deeply into lung tissue and have been shown to increase premature death in people suffering from heart disease and lung disease., Large particulates can cause eye, lung, and throat irritation. Exposure has also been linked to increased respiratory symptoms, decreased lung function, asthma, chronic bronchitis, irregular heartbeats, and heart attacks. Asthma is one of the most common chronic childhood diseases affecting 7.1 million children. Direct medical costs of asthma total $50.1 billion annually, while lost productivity adds $6.1 billion in costs. Over the course of a lifetime 38.4 million Americans have been diagnosed with asthma. Estimates on the number of premature deaths resulting from combustion emissions are 200,000 annually.
Air pollution has decreased in recent years, but in some areas pollution levels are still high. Individuals can reduce their contribution to air pollution by decreasing fossil fuel consumption and wood burning. Individuals can lower their risk of adverse health effects by monitoring air quality at www.airnow.gov. Health and economic benefits of lower air pollution are clear in the EPA’s prospective study on the Clean Air Act. The EPA estimates that the Clear Air Act prevented 130,000 heart attacks, 1.7 million asthma attacks, and 13 million lost workdays between 1990 and 2010.
Healthy People 2020’s leading health indicator for environmental health is to reduce the number of days the Air Quality Index (AQI) exceeds 100, weighted by population and AQI.
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