What is ground-level ozone?
Ground-level ozone – or “bad” ozone – is created by chemical reactions between oxides of nitrogen and volatile organic compounds in the presence of sunlight. Emissions from industrial facilities and electric utilities, motor vehicle exhaust, gasoline vapors and chemical solvents are some of the major contributors to the creation of ground-level ozone. Ground-level ozone is the primary ingredient of smog. Sunlight and hot weather cause ground-level ozone to form in harmful concentrations in the air. As a result it is known as a summertime air pollutant.
But I thought ozone was good. What gives?
“Good” ozone occurs naturally in the stratosphere approximately 10 to 30 miles above the earth’s surface and forms a layer that protects life on earth from the sun’s harmful rays.
Why is ground-level ozone harmful?
Breathing ground-level ozone can trigger a variety of health problems, including chest pain, coughing, throat irritation and congestion. It can worsen bronchitis, emphysema and asthma. Ground-level ozone also can reduce lung function and inflame the lining of the lungs. Repeated exposure may permanently scar lung tissue.
Ground-level ozone also damages vegetation and ecosystems. “Ground-level ozone has been shown to reduce agricultural yields for many economically important crops,” says George Dickert, extension agent with the Clemson University Cooperative Extension, Spartanburg office. ” It certainly has the potential to cause damage to some of our fruit and vegetable crops in this area. Lower yields mean lower profits for our growers (and) higher food prices for the consumer.”
How bad is the ground-level ozone problem in Spartanburg County?
Spartanburg County exceeded the EPA’s 1997 8-hour ozone standard of 0.08 parts per million (ppm) and narrowly attained the standard in December 2007. DHEC data from the Spartanburg monitor has shown average ozone levels at 0.083 parts per million, which is over the EPA current standard of 0.08 parts per million. Spartanburg is only in compliance by virtue of the fact that the EPA rounds figures down.
What if Spartanburg County does not meet Clean Air Standards?
A non-attainment designation will mean a loss of Federal Highway dollars (Spartanburg County received $ 6m last year) and a loss in economic development opportunities. In two counties alone in Alabama – Jefferson and Shelby – county developers had to pass on 15 projects due to the EPA’s air quality non-attainment designation. These projects represented 11,000 jobs and $ 4.6 billion in capital expenditures from 1990 -2000.
Why is 2010 such an important year in regards to ground-level ozone?
March of 2010 National Ambient Air Quality Standards (NAAQS) were to be lowered to 0.075, but now EPA is proposing to strengthen the 8-hour “primary” ozone standard, designed to protect public health, to a level within the range of 0.060-0.070 parts per million (ppm). Data from this year will be crucial in determining if Spartanburg County meets the new, tougher Clean Air Standards that take effect and thus avoids possible federal penalties.
To learn more visit the website of the federal Environmental Protection Agency.
Sources:
Environmental Protection Agency, epa.gov
Community Indicators Report, Spartanburg County Foundation
