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Executive Summary
Air pollution has been declining for decades across the United States, yet most Americans still believe air pollution is a growing problem and a serious threat to their health. The reason: most information on air pollution from environmentalists, regulators and journalists–the public’s main sources for information on the environment–is false. Air quality in America’s cities is better than ever. Between 1980 and 2005:
Fine particulate matter (PM2.5) declined 40 percent.
Peak 8-hour ozone (O3) levels declined 20 percent, and days per year exceeding the 8-hour ozone standard fell 79 percent.
Nitrogen dioxide (NO2) levels decreased 37 percent, sulfur dioxide (SO2) dropped 63 percent and carbon monoxide (CO) concentrations were reduced by 74 percent.
Lead dropped 96 percent.
What makes these air quality improvements so extraordinary is that they occurred during a period of increasing motor vehicle use, energy production and economic growth. Between 1980 and 2005:
Automobile miles driven each year nearly doubled (93 percent) and diesel truck miles morethan doubled (112 percent);
Tons of coal burned for electricity production increased about 61 percent; and
The real dollar value of goods and services (gross domestic product or GDP) more than doubled (114 percent).
Air pollution of all kinds declined sharply because of cleaner motor vehicles, power plants, factories,home appliances and consumer products.
Not only are Americans unaware that air quality has improved, they also harbor fears about air pollution that are out of proportion to the minor health risks posed by today’s historically low air pollution levels:
The prevalence of asthma rose 75 percent from 1980 to 1996, and nearly doubled for children; however, air pollution cannot be the cause, since it declined at the same time asthma increased.
Emergency room visits and hospitalizations for asthma are lowest during July and August,
when ozone levels are highest.
Reducing nationwide ozone from 2002 levels (by far the highest levels of the last six years) to the federal 8-hour ozone standard would reduce respiratory hospital admissions by 0.07 percent and asthma emergency room visits by only 0.04 percent, according to the Environmental Protection Agency (EPA) and California Air Resources Board (CARB).
Regulators, scientists and journalists have all played a role in perpetuating baseless fears. For example:
Studies that report harm from air pollution are more likely to be published and receive press coverage than studies that do not.
Government offi cials fund much of the research, and the funding is provided with the explicit intent to provide proof of harm from air pollution.
Regulators create fear through regional air pollution alert systems, such as “code red” days; even though pollution levels are dropping, the number of warnings increases because of increasingly tighter standards.
This constant stream of alarmist studies and air pollution warnings maintains unwarranted anxiety that air pollution is causing great harm. Furthermore, omission of contrary evidence on air pollution and health is common among researchers, journalists, activists and regulators, causing claims of harm from air pollution to appear more consistent and robust than suggested by the actual weight of the scientific evidence.
None of this would matter if air pollution could be reduced for free. But reducing air pollution is costly. Attaining the federal standards will cost tens to hundreds of billions of dollars per year. These costs are ultimately paid by people in the form of higher prices, lower wages and reduced choices.
Some requirements are especially counterproductive. For example, New Source Review (NSR) requires businesses to install “state-of-the-art” pollution controls to achieve the lowest possible emission rates when they build new plants. This gives businesses an incentive to keep older, less-efficient and higher-polluting plants operating well beyond their useful lives, rather than build less-polluting new plants. NSR harms consumers by slowing the pace of pollution reductions, raising the cost of any pollution reductions that do occur, and increasing the prices of consumer goods by slowing innovation and reducing competition.
Perhaps the most harmful aspect of the air quality regulation is that it has no negative feedbacks that would slow down or stop its bureaucratic expansion. Regulators’ jobs and powers depend on a public perception that air pollution is a serious and urgent problem. But regulators also fund much of the research intended to demonstrate the need for more regulation, and fund environmental groups to agitate for increases in regulators’ powers. Regulators also set the level of the health standards, meaning that they get to decide when their job is finished. Naturally, it never will be. And as the standards are tightened, the number of daily air pollution “alerts” increases, even as actual air pollution levels continue to decline.
The bureaucratic incentives built into air quality regulation explain why regulators and activists work so hard to make it appear that air pollution is still a serious problem, even as air pollution has reached historic lows that have, at worst, minor effects on people’s health.
Air pollution affects far fewer people, far less often and with far less severity than regulators, environmentalists, health scientists and journalists have led Americans to believe. By pursuing tiny or nonexistent health benefits at great cost, air pollution regulations are making us worse off.
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Joel Schwartz is a visiting scholar at AEI. |
