Air Quality and Health

The term “air pollution” refers to chemicals or particles in the air that can cause harm to humans or other living organisms and damage the natural environment.  In the San Antonio region, ground-level ozone is our primary kind of air pollution.

Ozone is a gas that occurs both in the Earth's upper atmosphere and at ground level.  Ozone can be "good" or "bad" depending on its location.  In an upper layer of the atmosphere called the stratosphere, the “ozone layer” is good because it blocks harmful ultraviolet rays.  Near the ground, in the air we breathe, ozone is bad because it hurts our lungs and harms other living things.

Ground-level ozone pollution is formed when Nitrogen Oxides (which are found in emissions from vehicles, refineries, and manufacturing or power plants) and Volatile Organic Compounds (which found in gasoline, paint, and cleaning fluids), combine together on hot, sunny days.  Because ozone forms during sunny and hot conditions, it is most likely to be a problem during San Antonio’s long, hot summers.  Our “ozone season” lasts from April 1 through October 31.

People who are young, who already have breathing problems, or who exercise or work outdoors are harmed the most by ground-level ozone pollution.  Symptoms of ozone exposure include coughing, wheezing, pain when taking a deep breath, and breathing difficulties during exercise or outdoor activities.  In addition to the respiratory symptoms mentioned above, ozone can inflame airways, aggravate asthma or other respiratory diseases, and increase one’s susceptibility to respiratory infection.  Long-term exposure can also accelerate aging of the lungs, diminish lung capacity, and decrease lung function.

When scientists think there will be an unhealthy level of ozone the next day, the government sends out an Air Quality Health Alert warning.  On an Air Quality Health Alert day, it is not a good idea to be outside for long periods of time, especially if you are in a more susceptible category.  If you would like to receive an email warning of an Air Quality Heath Alert, click here.

How Can We Reduce Ozone?

A large proportion of the ground-level ozone generated in the San Antonio area comes from the exhaust and fumes from vehicles.  If we reduce the amount of exhaust and fumes from vehicles, we can reduce the amount of the harmful ozone we have in the air.  There are a number of ways we can do this: 

Drive less

·         Combine errands into as few trips as possible

·         Consider carpooling (you may find a carpool partner at NuRide.com)

·         Use public transportation (check VIA for San Antonio or ART for greater regional areas)

·         Walk or take a bike

Conserve fuel

·         Avoid aggressive driving:  start and stop gradually

·         Drive the posted speed limit or less

·         Avoid drive-thru lanes: go inside instead

·         Shut off the engine while waiting outside of schools, businesses, and so on

·         Keep excess weight out of your vehicle

·         Don’t continue to fill your gas tank after the pump has automatically shut off

·         Seal the gas cap tightly:  Turn the cap until it clicks three times

Avoid traffic delays

• Anticipate construction and other congested areas and take alternative routes
• Leave earlier or later than rush hours to avoid traffic

Also. . . .

·         Keep car engines maintained

·         Keep tires properly inflated

·         Consider buying a “cleaner” or more fuel-efficient vehicle

For more information, contact Annette Prosterman at (210) 362-5213 or aprosterman@aacog.com.