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    Smog: Not an Allergen, but an Irritant

    O is for Ozone

    Ground-level ozone is another big contributor to the smog problem. This isn’t the "good" ozone layer found high in the atmosphere that protects us from UV rays of the sun. Ground-level ozone is a pollutant produced when sunlight reacts with the chemical fumes our cars and industrial plants churn out. It aggravates asthma, irritates the lungs, and makes it difficult to breathe. Long-term inflammation from breathing in too much ground-level ozone can permanently scar lung tissue.

    Smog with high levels of ozone is also particularly damaging for people with asthma. Researchers found that during the 1996 Summer Olympics in Atlanta, peak morning traffic decreased by 23% and peak ozone levels also went down, by 28%. What else went down? Emergency room visits for kids with asthma, by a whopping 42%.

    Air pollution from high-ozone smog can make existing asthma symptoms worse as well as triggering the onset of the condition in the first place, Sublett says. And the closer you get to it, the worse your symptoms are likely to be. "There have been studies showing that children who live near high-traffic areas, such as expressways, have higher rates of asthma. And the increasing rate of asthma appears to directly correlate with the closer you live to high traffic levels."

    Staying Safe from Smog

    So what can you do to protect yourself or your child from smog if you have asthma or allergies? Since it’s usually not practical for most people to just move to a less-polluted area, here are some tips to try:

    • Keep track of the daily air quality index in your area by checking local news reports so you'll know how high the pollution levels will be that day. When the color-coded alert level reaches the orange level, the air is considered to be unhealthy for sensitive groups. People with respiratory conditions such as asthma, especially children, should take precautions. Stay indoors. If you must go outside, keep activity low and take frequent breaks.
    • When the air quality index goes past orange and up to the red alert level, the air quality is rated "unhealthy." People with asthma or severe allergies should stay indoors as much as possible and avoid outdoor activity.
    • If you must go outside when the air quality index is poor, do it in the morning, before the heat of the day generates more smog and ozone, and avoid exercising outdoors.
    • Wear a mask to cover your mouth and nose when you go outside. It can help filter out irritants that aggravate allergy and asthma symptoms.
    • Outdoor air pollution can also get inside. Make sure your heat and air conditioning system has a MERV 11 or 12-level filter to screen out particulates. During the spring months, when you’re tempted to open the windows, check air quality levels first. If they’re high, resist the spring air and use a circulating fan instead.

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    Reviewed on October 24, 2011

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