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Posted at 11:00 AM ET, 05/06/2010

'Be air aware' this week

D.C. receives failing grade in air quality report

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How did you get to work today? Car? Bicycle? Your own two feet?

Sunday kicked off Air Quality Awareness Week, an annual observance by the U.S. Environmental Protection Agency (EPA) and National Weather Service to encourage citizens to "be air aware." It couldn't come at a better time.

According to the American Lung Association's recently released State of the Air 2010 report, when it comes to air quality in the D.C. metro area, there's some bad news and some good news. Which would you like first?

Keep reading for more about the region's air quality status and what you can do, after the poll...

The good news is that, nationwide, as well as in the D.C. metro area, air quality slightly improved last year for ground-level ozone and particle pollution, two of the most dangerous pollutants to human health. In the report, the Baltimore-Washington-Northern Virginia region ranked 16th out of the 25 U.S. cities most polluted by ground-level ozone (down from 14th in 2009) and 18th out of the 25 U.S. cities most polluted by short-term particle pollution (also down from 14th in 2009).

The bad news is that D.C. is still one of the most polluted cities in the country: Despite our improvement, we received a big, fat, failing "F" ... again.

The main culprits, as you may have guessed, are power plants, industry and vehicles. According to the EPA, emissions from passenger cars and trucks are responsible for 27 percent of U.S. air pollution (Side rant: I can't tell you the number of cars I see while waiting for the bus each morning that are occupied by only one person ... Usually, after 15 to 20 in a row, I stop counting. That's a whole lot of cars for a small number of people. Meanwhile, I involuntarily breathe in the fumes until the bus arrives. I often wonder if I should be wearing a gas mask during my commute).

Under the Clean Air Act, EPA monitors six main air pollutants: ground-level ozone, particle pollution, carbon monoxide, sulfur oxides (SOx), nitrogen oxides (NOx) and lead. The diameter of particle pollution (aka "haze") can be more than 30 times smaller than that of a single human hair, and therefore very easily inhaled and lodged into our lungs.

Ground-level ozone (aka "smog," as opposed to stratospheric ozone that protects us from harmful ultraviolet rays) is formed most often during summer, when NOx react with volatile organic compounds and sunlight -- a toxic mix that can affect everyone, especially children, older adults and those with asthma, cardiovascular disease or weakened immune systems. From 2006 to 2008, D.C. had only four "Red" ozone alert days on the EPA's Air Quality Index, which was unusually low. We did, however, experience 47 "Orange" ozone alert days.

Besides sunlight, other weather conditions can exacerbate the effects of air pollution too. Wind can carry pollutants hundreds of miles -- take northern New England, for example, which gets most of its air pollution from westerly winds that carry industrial pollutants from the Midwest, or Iceland's volcanic ash traveling to Europe in recent weeks. Temperature inversions can also trap pollutants in a layer of cooler air near the Earth's surface, sometimes for days.

To protect your health, the most important thing you can do is stay tuned to the Air Quality Index forecast each day throughout the summer, and heed "Orange" and "Red" warnings, especially if you are in one of the groups sensitive to air pollution.

As an alternative, if you want to escape to the cleanest air in the world, all you have to do is put on your parka and head to the South Pole. Other options closer to home include: Bismark, North Dakota; Cheyenne, Wyoming; and Alexandria, Louisiana ... the cleanest cities in this year's State of the Air report.

More information:
CWG's D.C. Area Pollen, UV and Air Quality page
EPA's Local Air Quality Index forecast
DC air quality webcam
Quiz: How much do you know about air quality?
AirNow tips: What you can do

By  |  11:00 AM ET, 05/06/2010

Categories:  Environment, Environment

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