California Considers Stringent Ozone Standard

Published May 1, 2005

The staff of the California Air Resources Board (CARB) has proposed a stringent new eight-hour ozone standard for California. It would be the toughest in the nation and far more stringent than the U.S. Environmental Protection Agency’s (EPA) current eight-hour ozone standard.

CARB issued a Draft Staff Report on the standard on June 21, 2004 and a final version on March 12, 2005.

Proposed Health Benefits Minimal

An analysis of the data shows CARB’s proposed ozone standards will be very costly for Californians, while conferring few benefits.

Even by CARB’s own estimates, reducing ozone from current levels to the proposed standards will result in small and imperceptible improvements in public health. For example, CARB estimates a 0.06 percent reduction in premature deaths, a 0.28 percent reduction in respiratory hospital admissions, and a 0.49 percent reduction in asthma-induced emergency room visits.

Even these estimates are inflated, however, because CARB overestimated the health effects of low-level ozone exposure, according to researchers in the field. Claims about the health benefits of reducing ozone below the relatively low ozone levels experienced today, they note, are based mainly on epidemiological studies reporting small statistical associations between ozone and health outcomes. But a number of researchers have argued that many of these statistical associations are more a product of data mining than a real cause-effect relationship between low-level pollution and health.

Studies Question Health Risks

A study published in 2004 in the Journal of Environmental Economics and Management, “Measuring the Health Effects of Air Pollution: To What Extent Can We Really Say that People Are Dying from Bad Air?” assessed the relationship between ozone and mortality, concluding the effect of ozone on mortality is statistically indistinguishable from zero.

CARB based its mortality benefit estimates mainly on the results of a World Health Organization (WHO) analysis of several single-city studies addressing the overall relationship between ozone and mortality. However, the WHO itself recommended its ozone-mortality relationship should be adjusted downward by one-third due to publication bias. As the WHO document noted, “Publication bias arises because there are more rewards for publishing positive or at least statistically significant findings. It is a common if not universal problem in our research culture.”

The ozone-mortality relationship was borderline statistically insignificant after WHO’s recommended adjustment.

Another major study, the National Morbidity, Mortality, and Air Pollution Study (NMMAPS), does not suffer from publication bias, because it applies the same analytical methods to pollution and mortality data for 95 different U.S. cities. A 2004 NMMAPS report on the relationship between ozone and mortality found an ozone effect 70 percent lower than the result derived from meta-analysis of single-city studies, and concluded that publication bias inflates the ozone health effects estimated.

CARB fails to account for these factors in its estimates of mortality benefits from ozone reductions.

Regulations Costly, Counterproductive

Attempting to attain CARB’s proposed ozone standard will impose costs on Californians likely to be tens of billions of dollars per year. These regulatory costs will reduce people’s spendable incomes, causing damage to Californians’ health, welfare, and quality of life far in excess of the tiny health improvements from additional ozone reductions.

The South Coast Air Quality Management District (SCAQMD), just one of many air quality districts in California, projects that attaining the current federal one-hour ozone standard in the South Coast region of California will cost about $4 billion per year in 2010, and $6 billion in 2020. A December 1999 study estimated the cost of attaining the federal eight-hour standard at $16.6 billion per year in the South Coast. Costs of attaining the federal eight-hour standard statewide would be much higher, of course, and attaining CARB’s proposed statewide standard would be much higher still.

Risk analysts estimate that each $17 million in additional costs induces one additional death by diverting resources away from other risk-reduction expenditures, such as safer cars or additional health care. CARB’s proposed standard thus would kill hundreds more people each year than it saved. CARB predicts the incremental benefit of its proposed standard would be to reduce mortality by 150 lives per year. But attaining the standard will kill the same number of people if attaining the standard costs $2.55 billion per year ($17 million x 150 = $2.55 billion).

If the standard costs more than $2.55 billion per year, the CARB standards will result in more deaths than saved lives. This appears to be the most likely result, as the CARB standard will cost many times more than $2.55 billion per year.

Joel Schwartz ([email protected]) is a visiting fellow at the American Enterprise Institute, a senior fellow with the Reason Public Policy Institute, and author of the AEI report Finding Better Ways to Achieve Cleaner Air (2004).