KU Children's Environmental Health Initiative

OZONE

What is ozone?

Any discussion of ozone requires the understanding of an important distinction. Ozone in the upper portion of the atmosphere is vital to protecting life on earth from the ultraviolet rays of the sun; hence, this is beneficial ozone. By contrast, harmful ozone is found in the lower layers of the air. This is an abnormal condition. Ozone is not emitted directly into the air from pollutant sources. Rather, it forms in the atmosphere from the chemical stew created by the action of sunlight on nitrogen oxides and volatile organic compounds. Both of these pollutants appear in the emissions from motor vehicles, industrial processes, and electric utility generation. Ozone values are of much greater concern in the summer due to the important role of high temperatures that foster its formation.

How is ozone regulated?

EPA is the federal agency responsible for establishing air quality standards. The task in regulating a pollutant is to set a standard that protects human health. Provisions of the Clean Air Act require EPA to continuously evaluate the research about the harm caused by ozone, especially in sensitive populations such as those with a respiratory ailment.

The monitoring sites in Kutztown and Reading measure ozone. Instead of the technical measurements, all the values for the monitors reported on the Children's Environmental Health website mentioned on the home page are translated into an Air Quality Index value that distinguishes among the classes of good, moderate, unhealthy for sensitive groups (such as those with asthma), unhealthy, very unhealthy, and hazardous. Each is coded with a different color from green to dark red, indicating the severity of the level.

How does all this relate to Berks County?

One can be guardedly optimistic about ozone levels here in Berks County. The optimistic part is that in September 2007 the County's designation was changed from non-attainment area to maintenance area. This means that the County did not originally meet the 1997 standard when it was implemented. But, the Pennsylvania Department of Environmental Protection petitioned the EPA to change the designation based upon the ozone monitoring data for 2003-2005. While the County is now designated to be in attainment, it carries the maintenance label because there must be a plan in place (called a State Implementation Plan) that documents how the County will be able to maintain ozone levels below the 1997 standard. Click here for a map of the United States (US) counties that are non-attainment and maintenance areas. Note carefully that the counties in non-attainment status include a sizeable portion of the US population along the East coast.

One additional reason to be optimistic is that Berks County is anticipated to be in compliance with the new 2008 ozone standard according to the EPA map shown below. The old 1997 standard was 0.08 parts per million (ppm) while the new 2008 standard is 0.075 ppm. Click here for another map that dentifies the 345 counties that violate the new standard based on the monitoring data from 2004-2006. Is this map understating the problem? For Berks County, the answer is an emphatic "yes." An investigation of the County Air Quality Reports on the AirData portion of the same agency reveals that Berks County ozone values were 0.076 in 2004, 0.085 in 2005, and 0.078 in 2006. These values mean that Berks County met the 1997 standard in 2004 and 2006. All three years are violations of the 2008 standard. In 2007, the value was 0.082, technically in compliance with the 1997 standard because of rounding, but in violation of the 2008 standard. Clearly, all of this is reason enough to use the word "guardedly" when discussing ozone accomplishments.

A second reason "guardedly" is appropriate is that the map mentioned in the preceding paragraph shows that counties on either side of Berks, except for the northwest, are all in violation of the new standard, and the ones to the southeast are still in violation of the old standard (as shown on the first map). This is problematic for Berks County residents given the transport of ozone throughout southeastern Pennsylvania.

Still a third reason to be cautious about the ozone data for Berks County is the concern about the new standard. Any change in a standard is studied in an exhaustive manner. The scientists at EPA are assisted by an expert group known as the Clean Air Scientific Advisory Committee. This group recommended to EPA that the new standard be set between 0.06 and 0.07 ppm based on research that found ozone to be more harmful than previously thought. Therefore, Berks County has achieved a level below a standard, but that may be only a regulatory achievement. The bottom line is clear - the population in Berks and surrounding counties can still be exposed to levels of ozone that are harmful. Plus, Berks County is nowhere near the level needed to meet the even weak 2008 standard, much less the standard recommended by EPA's own expert panel.