By Sabri Ben-Achour
Dr. Jeffrey Dubin is an emergency physician at Washington Hospital Center. He says when the air quality gets bad - code orange or even worse, code red days - people suffer.
"The typical complaint when people first walk in: 'how can we help you--''I'm having trouble breathing,'" he says.
It's usually people with asthma or lung disease like emphysema.
"People can be walking to the bus, and suddenly start having an asthma attack because the air quality is so bad and they wind up coming to see us," he says.
So what is in our air that causes this?
"Ozone," says Rick Saylor, a physical scientist with the National Oceanic and Atmospheric Administration in Silver Spring.
You might've heard of ozone: it's kind of a big deal - it makes up the ozone layer that keeps us from being fried by the sun. But...what is it?
"Ozone is a special form of oxygen, three oxygen atoms," says Rick Saylor, a physical scientist with the National Oceanic and Atmospheric Administration in Silver Spring.
"It reacts with just about everything it comes into contact with; when you breathe in air that contains ozone it can react directly with the tissues in your lungs."
But we're not high up in the ozone layer, so where does it come from down here?
"It's very complex," says Saylor.
Turns out there are literally thousands of reactions in the atmosphere that are involved, but basically..."You need a pollutant called nitrogen oxides, plus you need hydrocarbons, and you need sunlight," says Saylor.
Those ingredients make ozone, they make it faster on hot days, and they keep it from being naturally broken down.
"We do not meet federal standards for ozone," says Joan Rohlfs, who heads environmental research for the Metropolitan Council of Governments.
So if pollution creates ozone, where does all the the pollution come from? Well, she says...a lot of places.
She says Nitrogen Oxides basically come from anything that burns fuel.
"Buses, cars, trucks, lawnmowers, construction equipment," she says.
And of course power plants are a huge contributor.
Hydrocarbons can come from anywhere that creates chemical vapors.
"Dry cleaners, or gasoline stations, or asphalt paving for example," she says.
Now, it's not totally our fault; nature has a hand in this too. Trees, for all the good they do, make a lot of hydrocarbons, especially oak trees.
And Rohlfs says the weather has a lot to do with bad air days too. Weather patterns can blow in pollution from distant power plants or forest fires. Or, like last week, they can smother the region and let it stew in it's own dirty air.
The good news is that the number of bad air days has been dropping, slowly, over the past ten years.
"It’s due, we think, to the controls that are being placed on the power plants in this region," says Rohlfs. "They have stronger controls that they put in place a few years ago. That’s starting to take effect. We have cleaner cars now, and people and companies are starting to clean up their buses."
And there's everyday kind of things people can do too: take more public transportation, don't fill up at the gas station during the heat of the day, postpone mowing the lawn.
It adds up. And it just might save someone a trip to the hospital.