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Summary
Ozone is a gas. It can be good or bad, depending on where it is. "Good" ozone occurs naturally about 10 to 30 miles above the Earth's surface. It shields us from the sun's ultraviolet rays. Part of the good ozone layer is gone. Man-made chemicals have destroyed it. Without enough good ozone, people may get too much ultraviolet radiation. This may increase the risk of skin cancer, cataracts, and immune system problems.
"Bad" ozone is at ground level. It forms when pollutants from cars, factories, and other sources react chemically with sunlight. It is the main ingredient in smog. It is usually worst in the summer. Breathing bad ozone can be harmful. It can cause coughing, throat irritation, worsening of asthma, bronchitis, and emphysema. It can lead to permanent lung damage, if you are regularly exposed to it.
Environmental Protection Agency
Learn More
- Air Pollution and Asthma (Nemours Foundation) Also in Spanish
- AirNow.gov (Environmental Protection Agency)
- Ground-Level Ozone Pollution (Environmental Protection Agency)
- Ozone Air Purifiers: Can They Improve Asthma Symptoms? (Mayo Foundation for Medical Education and Research) Also in Spanish
- Ozone Generators That Are Sold as Air Cleaners (Environmental Protection Agency)
- Sunwise (Environmental Protection Agency)
Related Issues
- AirNow.gov (Environmental Protection Agency)
- Green Vehicle Guide (Environmental Protection Agency)
Clinical Trials
-
ClinicalTrials.gov: Ozone Exposure
(National Institutes of Health)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: Early-Life Ozone Exposure and Asthma and Wheeze in Children.
- Article: Effect of environmental pollutants particulate matter (PM(2.5), PM(10)), nitrogen dioxide (NO(2)),...
- Article: Relationships between fixed-site ambient measurements of nitrogen dioxide, ozone, and particulate...
- Ozone -- see more articles
Children
- Air Pollution and Asthma (Nemours Foundation) Also in Spanish
- Sunwise (Environmental Protection Agency)
The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.