Outdoor Air Quality

Scientists have done many studies which have linked ground-level ozone exposure to a variety of problems such as:

• Airway irritation, coughing, and pain when taking a deep breath.
• Wheezing and breathing difficulties during exercise or outdoor activities.
• Inflammation of the airways.
• Aggravation of asthma and a higher chance of getting respiratory illnesses like pneumonia and bronchitis.

According to the published literature, air pollution has been associated with premature death; increased rates of hospitalization for respiratory and cardiovascular conditions; adverse birth outcomes; and lung cancer ¹². Air pollution places a large economic burden on the country. In a report prepared for the American Lung Association, Cannon (1990) estimated that air pollution-related illness costs approximately $100 billion dollars (1988 dollars) each year in the United States, with an estimated number of excess deaths ranging from 50,000 to 100,000 per year (Dockery and Pope 1994). More than half of the U.S. population, or approximately 159 million Americans, live in counties with unhealthy levels of air pollution in the form of either ozone or particulate matter.³

---

Ozone

Ozone is a gas that you cannot see or smell. "Good" ozone occurs naturally in the sky about 10 to 30 miles above the Earth's surface. It forms a layer that protects life on Earth from the sun's harmful rays. Ground-level ozone is also called "bad" ozone because it is harmful to health when it is in the air we breathe. Many urban areas, like big cities, tend to have higher levels of bad ozone. Rural areas have bad ozone, too, because the wind carries ozone and the pollutants that cause it to form hundreds of miles away from their original sources. Studies have shown that being exposed to bad ozone can:

• Cause respiratory symptoms like coughing or pain when you take a deep breath.
• Make asthma worse.
• Cause lungs to get inflamed.
• Temporarily decrease the lung capacity of healthy adults.
• Permanently scar lung tissue when it is breathed in at high levels over long periods of time

Particle Pollution Or Particulate Matter

Particle pollution, or particulate matter, consists of particles that are present in the air, such as dust, dirt, soot and smoke, and little droplets of liquid. Some particles are large or dark enough and can be seen, like soot or smoke. Other particles are too small to be seen. Being exposed to high levels of particle pollution for more than a year is linked to heart and lung problems such as:

• Breathing problems.
• Reduced lung function.
• Chronic bronchitis.
• Heart and other cardiovascular diseases. These problems may lead to more hospital stays, more emergency department visits, and even premature death. Sensitive people such as older adults, people with diseases like asthma or congestive heart disease, and children are more likely to be affected by breathing in PM_2.5 (also called fine particle pollution). Being exposed to high levels of particle pollution for short periods of time, like hours or a few days, can:
• Make lung disease worse.
• Cause asthma attacks.
• Make it easier to develop bronchitis.
• Make it easier for people to get respiratory infections.

In people with heart disease, inhaling high levels of PM_2.5 for a short time has been linked to heart attacks and irregular heartbeats. Short-term exposure has also been linked with premature deaths, usually in people who already have a serious chronic health problem such as lung or heart disease. Healthy children and adults usually do not develop serious problems from short-term exposure to high levels of particle pollution. They may have minor problems, however, like a scratchy throat or scratchy eyes, when particle levels are high.

People with lung disease, children, older adults, and people who are active outdoors can be affected when ozone or PM levels are unhealthy. In people with heart diseases, short-term exposure to PM_2.5 has been linked to heart attacks and irregular heartbeats. Short-term exposure has also been linked with premature deaths, usually in people who already have a serious chronic health problem such as lung or heart disease. Healthy children and adults usually do not develop serious problems from short-term exposure to high levels of particle pollution. They may have minor problems, like a scratchy throat or scratchy eyes, when particle levels are high.

If you have asthma, a chronic lung disease, or cardiovascular disease, smoke exposure can aggravate these conditions. People with heart or lung disease should follow their health management plan from their health care provider. People with asthma should follow a prescribed asthma management plan. Follow your doctor's advice about medicines if you have asthma or another lung disease. In smoky conditions, if you develop symptoms which do not respond to your usual medication, see your health care provider immediately. Call your doctor if your symptoms worsen. Prolonged exposure to smoke of all kinds is harmful to people of all ages.

• Air Quality - Ozone Level
• Air Quality - Particulate Matter (PM2.5) Level

• Annual Number of Days With Maximum 8-Hour Average Ozone Concentration Over the NAAQS by Count
• Annual Number of Person-days with Maximum 8-hour Average Ozone Concentration Over the NAAQS by County
• Annual Number of Person-days with PM2.5 Levels Over the NAAQS by County
• Annual Percent of Days with PM2.5 Levels Over the NAAQS by County
• Annual Average Concentration of PM2.5 (mcg/m3) by County
• LURBME Model: Annual Average Concentration of PM2.5 (mcg/m3) by County

• Air Quality Ozone Days and Person-Days Metadata File
• Air Quality PM2.5 Annual concentration Metadata File
• Air Quality PM2.5 Annual Number of Person-Days Metadata File
• Air Quality PM2.5 Annual Percent of Days Metadata File