- With Mayo Clinic asthma and allergy specialist
James T. Li, M.D.
read biographyclose windowBiography of
James T. Li, M.D.
James T. Li, M.D.
"People with allergy or asthma can lead full and healthy lives." — Dr. James Li
Dr. Li is chair of the Division of Allergic Diseases in the Department of Internal Medicine and a board-certified asthma and allergy specialist. He hopes his expertise and the information on the site educates health care consumers in an area of rapid change both in medications and diagnoses.
"There are a lot of misperceptions about allergy and asthma," says Dr. Li, a New York City native who has been with Mayo since 1985 and works with a group of subspecialists in allergy, asthma and immunology. "I believe it's important to provide truthful, accurate information about allergy and asthma to the public. The more people know, the better they can take care of these conditions."
Dr. Li is a professor of medicine at Mayo Clinic College of Medicine. He is a past director of the American Academy of Allergy, Asthma & Immunology and is a director of the American Board of Allergy and Immunology. He is a fellow in the American College of Allergy, Asthma & Immunology and is a director of the American Board of Internal Medicine.
The American College of Allergy, Asthma & Immunology honored him with the Distinguished Service Award and the American Academy of Allergy, Asthma & Immunology with its Special Recognition Award.
More answers
- Asthma: Why are symptoms worse during my period?
- Asthma diet: What you eat can affect asthma symptoms
- Reactive airway disease: Is it asthma?
- Asthma without wheezing: Is this possible?
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Question
Ozone air purifiers: Can they improve asthma symptoms?
My daughter has asthma. Would she benefit from an ozone air purifier in her room?
Answer
from James T. Li, M.D.
Despite manufacturer's claims, ozone air purifiers don't remove particles from the air that may trigger asthma attacks. In fact, inhaled ozone can make asthma worse.
Ozone generators sold as air purifiers intentionally produce the air pollutant ozone. The ozone molecule contains three atoms of oxygen. Two of these atoms form the basic oxygen molecule. The third atom can detach from the ozone molecule and reattach to molecules of other substances. This changes the chemical composition of the other substances — and forms the basis of manufacturer claims that ozone "purifies" the air. But inhaling ozone, even in small amounts, can irritate the lungs. Specific effects may include throat irritation, coughing, chest pain and shortness of breath, as well as an increased risk of respiratory infections.
Some ozone air purifiers are made with an ion generator or "ionizer" in the same unit. You can also buy ionizers as separate units. Ionizers remove particles from the air, causing them to attach to nearby surfaces or to each other and settle out of the air — but they may generate unwanted ozone. High-efficiency particulate air (HEPA) filters are more effective in removing allergens from the air, without posing any ozone concerns.
Next questionAsthma: Why are symptoms worse during my period?
- Tips to remember: Indoor allergens. American Academy of Allergy, Asthma and Immunology. http://www.aaaai.org/patients/publicedmat/tips/indoorallergens.stm. Accessed Sept. 16, 2008.
- Ozone generators that are sold as air cleaners. U.S. Environmental Protection Agency. http://www.epa.gov/iaq/pubs/ozonegen.html. Accessed Sept. 16, 2008.
