What Is Ozone?
Ozone high in the stratosphere - some six to seven miles above the ground - acts as an umbrella to shield us from dangerous sunlight. But when ozone occurs at ground-level, where we breathe, it's a harmful pollutant. The odorless, colorless gas reacts rapidly and strongly with living tissues as well as fabrics, dyes, rubber and other materials.
Ground-level ozone forms when pollutants called volatile organic compounds (VOCs) and nitrogen oxides react on hot, humid, sunny days. Cars, factories, boats, lawnmowers and other gas-powered equipment release the pollutants, as do lighter fluid, oil-based paints, and other household products.
Is Ozone Hazardous To My Health?
Yes. Because ground-level ozone reacts strongly with living tissues, such as your lungs, high concentrations can cause shortness of breath, coughing, wheezing and pain with deep breaths in people who are sensitive to ozone. People who suffer from lung diseases such as emphysema, bronchitis, pneumonia, asthma and colds can have even more difficulty breathing when ozone concentrations are high.
Children also are at increased risk for respiratory problems from ozone because they typically play outside for long periods of time during the summer and so have greater exposure to high ozone concentrations than do many adults. Also, children breathe more rapidly and so inhale more air pollution per pound of body weight than adults.
Adults who exercise outdoors on days when ground-level ozone concentrations reach unhealthy levels also are at increased risk for respiratory problems. Adults breathe more than 10,000 times a day when they are at rest, and that number increases when they exercise or work strenuously. As a result, exercising adults may take in 10 times as much air as when they're resting. Usually, the benefits of exercising outweigh the risks of ozone. If you know you are more sensitive to ground-level ozone, try to limit your time outdoors and the intensity of your activities.
To protect yourself from ozone-related health problems, listen and watch for notices that a Wisconsin Air Quality Watch Day has been called in the specified counties. Air Quality Watches indicate that predicted weather conditions could allow ground-level ozone concentrations to exceed the federal health standard. If you've noticed from past experience that you or your children are more sensitive to ozone, try to limit activities outdoors, especially in the late afternoon, on Air Quality Watch.