Ground-level ozone pollution, and what you can do about it

Most of us know that when ozone levels are high it is an unhealthy situation for some people. But you may not know what ozone is, or what you can do to help improve the problem of ground-level ozone.

Ozone is an oxygen molecule with three atoms of oxygen instead of the normal two. It is produced in nature, and in natural quantities is necessary in the process of oxidizing (breaking down) organic matter. But when it is produced in greater quantities as a result of human activities, and becomes concentrated at ground level, it can be quite harmful to humans, plants and animals.

Ozone is not a pollutant that is released into the air. It is produced by other pollutants (precursors) reacting with sunlight and heat. That is why ozone levels are higher in the summer months and during daytime hours. Weather and climate conditions, including wind currents, determine how high ozone levels become.

The reactions which create ozone primarily involve nitrogen oxide (NOx) and volatile organic compounds (VOCs). Sources of NOx are the combustion of fuel in automobiles, trucks and marine vessels, construction equipment, electrical power generation, natural gas furnaces and other industrial processes. VOCs come from organic chemicals which vaporize easily - service stations, vehicles, petroleum storage tanks and oil refineries. Trees and plants are also a major source of VOCs.

High ozone levels are most damaging to the health of people with lung disease, adults who engage in strenuous work or exercise outdoors, and children. Ozone in higher concentrations can cause shortness of breath, coughing or wheezing, headaches, nausea, and irritation of the throat and lungs. Ozone has been shown to increase asthma attacks. Children can be particularly sensitive to the effects of air pollution. Before about age nine, children do not have fully developed immune systems to fight respiratory pollutants. A given air pollution concentration will result in much higher doses in children because their lung volume in relation to body size is twice that of adults.

What can you do to improve air quality? Probably many things, but here are three major ones:

-Recycle. By recycling a ton of paper, 4,100 kilowatt hours of electricity are saved.

-Make environmentally friendly energy decisions. Generating electricity is the leading cause of industrial air pollution. One company, Green Mountain Energy, offers 100 percent pollution-free electricity in Texas. One of its facilities, the Wind Farm at Brazos, generates enough pollution-free electricity to power over 30,000 average homes. You can get more information on this company at www.greenmountain.com. Certain other electricity providers in Texas also offer products that come from at least 50 percent renewable resources such as solar, hydroelectric, wind, biomass and geothermal. To find out more about these offers, you can visit www.powertochoose.org.

-Consider buying a vehicle which uses less fuel and pollutes less. Motor vehicles are responsible for 49 percent of NOx pollution. According to the EPA, low emissions and good fuel economy are both important for the environment. To learn more about choosing a vehicle which is friendlier to the environment, visit www.epa.gov/greenvehicles.

To find out more about all kinds of environmental issues in Texas, visit the Texas Commission on Environmental Quality website (www.tceq.state.tx.us). You can even sign up to get area ozone alerts emailed to you.

(Near Northwest Banner, August 1, 2006)