Economists and environmentalists have disagreed about the costs and benefits of air pollution regulations aimed at cutting ozone and smog by reducing hydrocarbons, CO and NOx.

While the overall costs of catalytic converters and other hardware is about $10 billion per year, few agreed on the benefits.

One economist put benefits at only $2 billion per year, relying on well-documented obvious health benefits extrapolated from air pollution related acute health emergencies. (Freeman, 1982)

On the other extreme, the American Lung Association estimated potential benefits of pollution control at as much as $93 billion per year. (Cannon, 1990) And the Natural Resource Defense Council saw benefits from pollution control of total car and light truck air pollution of from $120 to $220 billion per year (Miller, 1993).

Other studies have looked at more specific questions. For instance a 1988 OTA study looked at a 35% reduction in nationwide emissions of smog-forming volatile organic compounds (VOCs) in the nation’s 90 dirtiest cities. This modest reduction of VOCs by controlling vapor pressure would cost between $8.8 billion and $12 billion annually, yet the acute health improvements that could result from these changes were valued in a 1991 follow up study at only $250 million to $1 billion annually. (Krupnick, 1991).

Of course, the conclusions of all these studies depended a great deal on their assumptions about what counts as a benefit. If only a reduced incidence of asthma attacks and other acute health effects are measured, then the benefits will be seen as relatively low. On the other hand, if generalized health benefits, improvements in crop yields and reductions in acid rain and global warming are factored in, as is the case in the NRDC report, benefits of hundreds of billions are conceivable.

Clearly, not every risk can be eliminated and not every particle of pollution can be controlled. On the other hand, not every claim of economic damage from pollution control is credible. A common sense approach weighs the various estimates and methods along with broad policy goals.