TCS Daily

State of the Scare

By Joel Schwartz - May 3, 2005 12:00 AM

Reporting on air quality has improved, but not by nearly as much as air quality itself. The American Lung Association's annual State of the Air report has also improved, but not by nearly as much as air quality reporting. Despite unprecedented gains in air quality during the last two years, State of the Air continues to exaggerate air pollution levels and health risks. And despite a few positive headlines about air pollution trends, journalists continue to parrot ALA's claims with little or no critical review of their veracity. We still have a long way to go before activists' and journalists' claims match air quality reality.

Smog Hits a Record Low

Recent air quality improvements are extraordinary. Days exceeding EPA's tough new 8-hour ozone standard dropped more than 50 percent nationwide between 2003 and 2004, even though 2003 was itself a record year.[1] Forty-four percent of ozone monitoring locations violated the standard as of the end of 2003, but only 31 percent as of the end of 2004. Both are huge improvements over the 1970s, when 80 percent of monitors violated the 8-hour standard.

The 2003 and 2004 ozone improvements were partially due to cool, wet weather. Nevertheless, other years have had weather unfavorable to ozone formation, but none have had ozone levels anywhere near as low as 2004. Ongoing declines in ozone-forming pollution are the main reason for the long-term downward trend. Four of the last five years were the four lowest ozone years since national monitoring began in the mid 1970s, suggesting that something more than random weather variations explains recent air quality improvements.

Levels of fine particulates (PM2.5) are also at record lows. Annual-average PM2.5 levels declined more than 14 percent between 1999 and 2004, and 45 percent between 1981 and 2004. Thirty-three percent of U.S. monitoring locations violated federal PM2.5 standards in 2001, but only 15 percent as of the end of 2004. Once again, both are huge improvements over the 80 percent violation rate during the early 1980s.

Readers of State of the Air don't learn any of this. The report doesn't say a word about 2004's pollution levels. Air quality progress receives a quick mention, but without any of the specific or quantitative details that would show the extraordinary magnitude of the improvements. Providing these details would undermine much of the impact of ALA's report, which likely explains the omission.

These air pollution improvements occurred despite large increases energy use and a doubling of total miles driven by motor vehicles since 1980. The story of the last hundred years has been more people, more highways, more cars, more energy, more wealth...and less air pollution. Ever improving technology has allowed us to have far cleaner air without the need to restrict people's choices about where and how to live, work, and travel.

Exaggerating Air Pollution Levels

ALA also exaggerates the amount of pollution in the air. State of the Air claims 152 million Americans, more than half the population, lives in areas that violate federal air pollution standards. In reality, fewer than half this number of people live in areas that violate federal pollution standards. Here's how ALA fudges the numbers:

First, if even one pollution monitor in a county violates a pollution standard, ALA counts everyone in the county as breathing air that violates the standard. For example, 99 percent of San Diegans live in areas that comply with EPA's 8-hour ozone standard. Only one rural area violates the standard, but ALA counts all 3 million people in the county as breathing air that violates the standard. This is not an isolated example. More than 90 percent of people in Cook (Chicago) and Maricopa (Phoenix) counties live in areas that comply with the 8-hour ozone standard, and even in Los Angeles County 60 percent of people live in areas that comply with the standard. These four counties alone are home to more than 21 million people, and ALA wrongly counts more than 16 million of them as breathing air that violates EPA's ozone standards. A similar over count can happen for particulate levels. Only one of Allegheny (Pittsburgh) County's dozen PM2.5 monitors violates EPA's 24-hour PM2.5 standard.

Second, for PM2.5 the problems with ALA's report go much deeper than merely counting clean areas as dirty. ALA bases its results on a much tougher 24-hour PM2.5 standard than EPA. The federal standard for maximum daily PM2.5 is 65 micrograms per cubic meter (ug/m3), but ALA uses a standard of 40 ug/m3 to count daily exceedances. More than 99.6 percent of the country complies with EPA's 24-hour PM2.5 standard. Yet by using a much tougher standard, ALA was able to claim 26 percent of Americans, more than 76 million people, live in areas with unhealthful short-term PM2.5 levels.

ALA can't take all of the blame for exaggerating PM2.5 levels. EPA helped by setting its Air Quality Index warning level at 40 ug/m3, departing from past practice with all other pollution standards of issuing an AQI warning only when pollution levels exceed the level of the federal standard. EPA thus created a much tougher "shadow" PM2.5 standard without going through the more rigorous review process required for legally binding air pollution standards. But having the shadow standard allows regulators and activists to create the public appearance of frequent dangerous PM2.5 levels even as virtually the entire nation actually complies with EPA's health standard.

Third, ALA used data for 2001-2003 for its estimates. But pollution levels were much lower in 2004. Using data for 2002-2004 would lower still further the number of Americans living in areas that violate EPA's health standards.

ALA also exaggerates the frequency with which any given area exceeds EPA's air pollution standards. State of the Air counts a pollution exceedance day for an entire county if even one pollution monitor in the county exceeds a pollution standard. For example, ALA claims Harris (Houston) County, Texas averaged 33 days per year exceeding the 8-hour ozone standard during 2001-2003. Yet the worst location in the county averaged just 15 exceedances -- less than half of what ALA claims -- while the average county location had seven exceedances. ALA claims to be reporting on Americans' risk from air pollution. Yet the report's numbers have nothing to do with any real person's actual air pollution exposure.

What's Health Got to Do with It?

Despite ALA's exaggerations, tens of millions of Americans really do live in areas that exceed EPA's health standards for ozone, PM2.5 or both. ALA creates the impression that everyone living in areas that exceed EPA's standards is suffering serious health damage or even death. In reality, EPA's pollution standards have become so stringent that exceeding them has few implications for people's health.

For example, EPA estimates that even large ozone reductions will result in tiny health improvements. In a recent study published in the journal Environmental Health Perspectives, EPA researchers estimated that reducing ozone from levels during 2000-2002 down to the 8-hour standard would reduce asthma emergency room visits by only 0.02 percent and respiratory hospital admissions by 0.04 percent.[2] EPA derived these results under the assumption that no health improvements result when ozone is reduced from levels already below EPA's standard. After adding in these additional benefits, the reduction in emergency room visits and hospital admissions would rise to about 0.1 and 0.2 percent, respectively, which is still an imperceptible improvement. Whatever public health benefits are available from lowering ozone, virtually all of them have already been achieved.

The California Air Resources Board's Children's Health Study followed more than 1,000 children from ages 10 to 18 during the 1990s and reported no relationship between ozone levels and lung function.[3] The CHS also reported that asthma incidence was 30 percent lower in areas with the highest ozone levels.[4] The CHS included areas of California that have by far the highest ozone levels in the country -- including areas that at the time averaged more than 100 days per year exceeding the 8-hour ozone standard and more than 50 days per year exceeding the much higher ozone levels of the old 1-hour standard. No area outside California has ever had ozone levels anywhere near this high, and even the worst California areas no longer approach these levels.[5]

ALA wants people to believe that current ozone levels around the U.S. are permanently damaging people's lungs. But the CHS concluded that even ozone levels much higher than ever occur today have no effect on children's lung development or function.

Both ALA and EPA claim that current, historically low PM2.5 levels are killing tens of thousands of Americans each year, but they ignore weaknesses in the studies EPA used to set its PM2.5 standards, and contrary evidence from other studies. For example, the American Cancer Society study, which provides the main support for EPA's annual PM2.5 standard and the mortality claims, reported that PM2.5 kills men, but not women; those with no more than a high school education, but not those with at least some college; former smokers, but not current or never smokers; and people who say they are moderately active, but not those who say they are sedentary or very active.[6] These biologically implausible results suggest that the claimed harm from PM2.5 is really the result of statistical confounding, rather than a real cause-effect relationship. EPA and ALA have also ignored a study of 50,000 veterans with high blood pressure that reported no relationship between PM2.5 levels and risk of death.[7] Researchers have reported related problems with studies of short-term PM2.5 health effects, also ignored by ALA and EPA.[8]

Even activists' own studies sometimes suggest air pollution is having a small effect on people's health. A study commissioned by the Clean Air Task Force estimated that a 75 percent reduction in U.S. power plant pollution would reduce the incidence of serious respiratory and cardiovascular health effects by 0.4 to 1.6 percent.[9] And even this study ignores the fact that high concentrations of ammonium sulfate, the type of particulate matter from power plants, have been shown to have no health effects in studies with human volunteers, including studies with elderly asthmatics.[10]

These are just a few among many examples of how the evidence for harm from current air pollution levels is far weaker than ALA claims. ALA wants Americans to believe that almost all respiratory disease and distress is due to air pollution. In reality, air pollution affects far fewer people, far less often, and with far less severity than environmental activists or government regulators would care to admit.

Even as air pollution continues to decline, activists' claims about air pollution levels and risks have become ever more urgent and extreme. ALA and other activists depend on public fear and outrage over air pollution to maintain their political power and keep the donations flowing. State of the Air's phony portrait of air pollution levels and risks helps to maintain this unwarranted climate of fear.

A Free Ride from the Press

Journalists bear much of the blame for State of the Air's undeserved public credibility. Each year dozens of newspapers around the country parrot the report's fake pollution claims without any critical review. Nevertheless, a few papers improved modestly this year, headlining their ALA stories with recent air quality improvements. The Atlanta Journal-Constitution began "Bad-air report skips over city; Atlanta drops off ozone list," and an Associated Press story led with "Advocacy group reports less air pollution." The Pittsburgh Post-Gazette noted that despite ALA giving a failing grade to Pittsburgh, many of the region's pollution monitors actually meet federal health standards. And the Los Angeles Daily News cited L.A.'s air pollution progress with "L.A. air graded as clearly bad; Pollution way down, but not far enough." Some of these stories still endorsed ALA's false claims about health and pollution levels, but at least they told readers that air quality was improving.

Despite this modest progress, most reporters are still merely a pass-through for ALA's misleading gloom and doom. This year's most egregious entry was the Oakland Tribune's "Air pollution still abysmal in Bay Area." It would be hard to make a more ridiculous statement about the San Francisco Bay Area's air quality. The entire region complies with all of EPA's air pollution health standards and has some of the cleanest air of any large metropolitan area in the entire world.

State of the Air is now in its sixth year, and not a single journalist has set out to independently verify ALA's quantitative claims about air pollution levels, trends, or health burdens.

Facts, Not Fear

Polls continue to show that most Americans believe air pollution has stayed the same or worsened over the last decade, will worsen in the future, and is a widespread and serious threat to health even at current, historically low levels. All of these beliefs are false. We can't expect ALA to make State of the Air correspond with reality, for reality is too benign to meet ALA's needs. But we should expect more from journalists and editors. It's time for the Fourth Estate to treat environmental activists with the same skepticism appropriate for other interested parties in environmental debates.

The author is Visiting Fellow, American Enterprise Institute.

[1] Data on air pollution levels and trends in this column come from EPA's AirData database, except for California data, which come from the California Air Resources Board.

[2] B. J. Hubbell, A. Hallberg, D. R. McCubbin et al., "Health-Related Benefits of Attaining the 8-Hr Ozone Standard," Environmental Health Perspectives 113 (2005): 73-82.

[3] W. J. Gauderman, E. Avol, F. Gilliland et al., "The Effect of Air Pollution on Lung Development from 10 to 18 Years of Age," New England Journal of Medicine 351 (2004): 1057-67.

[4] McConnell, R., K. T. Berhane, F. Gilliland, et al. (2002). Asthma in Exercising Children Exposed to Ozone: A Cohort Study. Lancet 359: 386-391.

[5] There is one exception. Arvin, a small town outside Bakersfield, averages more than 100 8-hour exceedance days each year and around 10 to 25 1-hour exceedances.

[6] C. A. Pope, 3rd, R. T. Burnett, M. J. Thun et al., "Lung Cancer, Cardiopulmonary Mortality, and Long-Term Exposure to Fine Particulate Air Pollution," Journal of the American Medical Association 287 (2002): 1132-41.

[7] F. W. Lipfert, H. M. Perry, J. P. Miller et al., "The Washington University-EPRI Veterans' Cohort Mortality Study," Inhalation Toxicology 12 (suppl. 4) (2000): 41-73.

[8] G. Koop and L. Tole, "Measuring the Health Effects of Air Pollution: To What Extent Can We Really Say That People Are Dying from Bad Air?" Journal of Environmental Economics and Management 47 (2004): 30-54. For a review of this problem, also see S. H. Moolgavkar, "A Review and Critique of the EPA's Rationale for a Fine Particle Standard," Regulatory Toxicology and Pharmacology in press: doi:10.1016/j.yrtph.2005.02.003 (2005).

[9] Abt Associates. The Particulate-Related Health Benefits of Reducing Power Plant Emissions, (Bethesda, MD: Clean Air Task Force, October 2000),

[10] Koenig, J. Q., K. Dumler, V. Rebolledo, et al. (1993). Respiratory Effects of Inhaled Sulfuric Acid on Senior Asthmatics and Nonasthmatics. Archives of Environmental Health 48: 171-5.


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