TCS Daily

Shooting Air Balls

By Kay H. Jones - June 17, 2003 12:00 AM

Earlier this month the American Lung Association (ALA) released its fourth annual report "State of the Air 2003." The ALA presented a county-level analysis of 1999, 2000, and 2001 ozone monitoring data for 692 counties. Based on its highly questionable grading system, 384 counties were graded "F," 33 got "Ds," 79 got "Cs," 53 got "Bs," and only 68 got "As." And 75 went ungraded because of incomplete data.

Based on these unrealistic and unscientific grades, the ALA reports exaggerated population at-risk estimates, such as "more than 137 million Americans continue to breathe unhealthy amounts of the toxic air pollutant ozone" (also known as smog). This is the total population living in counties receiving an "F" grade.

The ALA is essentially ignoring the relationship between current ozone levels and the National Ambient Air Quality Standard (NAAQS). The ozone NAAQS, which became more stringent in 1996, is fully compliant with the Federal Clean Air Act in terms of protecting the public health of the most sensitive segments of the nation's population. The U.S. Supreme Court validated this. Simple graphical and statistical analyses of the ALA's grading results clearly illustrate the report's lack of credibility.

Figure 1 shows a comparison of the ALA's scores for the most highly impacted counties in each of 41 states included in Table 4 of its report. One county had a higher score than the 40 shown on the figure, while other states with "A" or "B" grades were not listed.

The scores were plotted against the official EPA Design Value (D.V.) that is the measure of whether a county is in compliance with the eight-hour NAAQS. The D.V. is calculated by averaging the fourth highest monitored ozone value over a three-year period at the worst-case monitor in each county. Hence, a county is in attainment even if there are about nine days above 0.085 ppm over a three-year period. This provision of the NAAQS is needed to prevent counties or metro areas from bouncing in and out of attainment just due to year to year variation in summertime weather. The ALA chose not to recognize this fact by essentially setting its own set of standards. The graphed data shows the following:

  1. Counties that just attain the NAAQS will still get an ALA grade of "F."

  2. To receive an ALA "D" grade, counties would have to achieve an equivalent standard of .082 ppm.

  3. To receive an ALA "C" grade, counties would have to achieve an equivalent standard of .078 ppm.

  4. To receive an ALA "B" grade, counties would have to achieve an equivalent standard of .071 ppm.

  5. It is unlikely that any counties that currently experience only one day above .085 ppm in three years will ever achieve an "A" grade.
An additional analysis was conducted to see what ozone standard would have to be achieved to get an "A" grade. EPA Design Value data for counties that did not have any days above .085 ppm for the years 1997, 1998, and 1999 were statistically analyzed. The level of the standard would have to be .062ppm or 27 percent below the NAAQS for 50 percent of the counties to get an ALA "A" grade. The standard would have to be .050 ppm for 90 percent of the counties to get an ALA "A" grade. This is 41 percent below the current NAAQS.

Doesn't common sense tell us that if a county or metro area achieves the NAAQS that it should have an "A" grade and that based on the degree of non-compliance, lower grades would apply?

Furthermore, population at-risk analyses should minimally recognize the frequency and magnitude of the county-level exposures currently above the NAAQS as well as the recognized thresholds of each health effect. The ALA falsely implies that all of the susceptible subpopulations will suffer health effects at or even below the NAAQS. Such an assumption isn't even junk science. It's junk.

The ALA staff responsible for its grading system surely does not exhibit any training in statistical analysis of air quality data, much less in grading reasonably. The reality is that ozone air pollution levels have decreased dramatically in the last 30 years and most urban areas with few exceptions are now in or close to compliance with the national ozone standard.

Kay H. Jones, Ph.D., is a private consultant in Seattle, Washington. Dr. Jones received his Ph.D. in Environmental Engineering from the University of California, Berkeley. He served as the senior advisor on air quality at the Council on Environmental Quality under the Ford and Carter Administrations. His responsibilities included the preparation of the air quality status and trends chapter for inclusion in the President's Annual Environmental Quality Report to the U.S. Congress. He also served as the senior technical advisor and research manager at the Environmental Protection Agency in Washington D.C.

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