RENEE MONTAGNE, host:
This has been the hottest summer on record in many East Coast cities - and many other parts of the country. That heat has brought with it a lot of days with unhealthy air. At least 75 areas from Portland, Maine, to San Francisco are warning residents to expect high air pollution today. Here's NPR's Elizabeth Shogren with our report.
ELIZABETH SHOGREN: All the bad-air days mean that at day-care centers, like Little Flowers in Washington, D.C., children are spending a lot of time cooped up inside.
Ms. ELIANA NOGUCHI (Little Flowers Daycare): And now we're taking them outside for 15 minutes so they can play with the sprinkler.
SHOGREN: Eliana Noguchi says the children normally would go to the playground several times a day for 40 minutes each time. But with code red air quality, they get one short recess.
Ms. NOGUCHI: Ready? Go. Who's going to be the brave one? Come on. Come on. Let's go.
SHOGREN: As tiny feet slap the pavement in a happy sprinkler dance, Noguchi says some toddlers are missing. They have asthma, and their parents picked them up early to avoid even this brief time outside.
Norman Edelman, the chief medical officer for the American Lung Association, says children are especially vulnerable to bad air days, particularly if they have asthma.
Dr. NORMAN EDELMAN (Chief Medical Officer, American Lung Association): Kids are always running around, so they breathe a lot more for their size than adults do. So they take in more of this bad stuff.
SHOGREN: That means that even healthy children should limit their time outside on code orange days, when the air is unhealthy for sensitive groups; and on code red days, when the air is bad for everyone. Ozone and fine particles are the two types of pollution that trigger code red and orange days. Both are formed out of the exhaust from power plants, cars, and a lot of other things.
Edelman says, with ozone...
Dr. EDELMAN: The two bad chemical actors are oxides of nitrogen and hydrocarbons. When they're exposed to heat and sunlight, a chemical reaction takes place, which releases ozone.
SHOGREN: And when people breathe it in, it irritates their lungs.
Dr. EDELMAN: So if you look down the airway of somebody exposed to excessive ozone, it would look like a bad sunburn of the airways.
SHOGREN: And since children's airways are a lot smaller than adults, it doesn't take much swelling to cause an asthma attack.
High levels of fine particles also trigger bad air days in summertime, especially in the East. Coal-fired power plants are the main culprit and on the hottest days, they're working at full tilt to keep air conditioners running.�
The elderly, and people with lung and heart problems, are at high risk. But Edelman says even if you're healthy, you shouldn't ignore bad air days. It's probably best to do outdoor exercise in the morning, before the sun and exhaust have turned the air into an unhealthy soup.
(Soundbite of bat hitting softball)
Unidentified Man #1: Go. Go. Go.
SHOGREN: Not at - say, 5 p.m., when two teams of federal workers are slugging it out on a steamy softball field.
Unidentified Man #2: Run.
Unidentified man #3: Come on, Dwight. Come on. Let's go.
Mr. MATT UNGER (Army Corps of Engineers): I know two other teams played it safe today and called the next two games off. So, and it's really - it's not that bad out here.
SHOGREN: Army Corps of Engineers short stop Matt Unger says his players are used to the heat after serving in Iraq and Afghanistan.
Mr. UNGER: Oh, good hit. That's it.
SHOGREN: Turns out their opponents - self-described bureaucrats from the Government Accountability Office - are pretty tough, too.
(Soundbite of crowd chatter)
SHOGREN: Still panting from her run around the bases, Kim Gianopoulos admits that like a lot of other people, she doesn't pay much attention to air pollution alerts.
Ms. KIM GIANOPOULOS: You don't get too much opportunity these days to get out and have fun with your co-workers and do this kind of thing, so you've got to take advantage of it, you know.
SHOGREN: Dr. Edelman says if you do exert yourself on bad air days, don't ignore symptoms like burning lungs or irritated eyes.�
Elizabeth Shogren, NPR News, Washington.
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