21.8 We have several options for addressing air pollution.

Since air pollution often travels to areas that do not produce significant amounts of pollution themselves, regulating air pollution is a particular challenge. How does one country regulate pollution that travels through the atmosphere from another country?

In developed countries, the original approach to dealing with air pollution from human activities was to spread it out—the solution to pollution is dilution. Factories, power plants, and other point sources built tall smoke stacks to send emissions high into the atmosphere so that they wouldn’t pool at the site of production. The idea was that if dispersed, the amount of pollution in any one area would be too low to cause a problem. But this approach simply doesn’t work—industry releases too much pollution, and air circulation patterns cause some areas to get more than their share of pollution.

Eventually it became clear that regulation would be necessary. The typical approach in the 1970s was command and control regulation, a type of regulation that sets national limits on how much pollution can be released into the environment and imposes fines or even brings criminal charges against violators who release more than is allowed. Both Canada and the United States have passed command and control regulations to improve air quality. The United States passed its Clean Air Act in 1963, and Canada followed with our Clean Air Act in 1970. Canada’s Clean Air Act was later subsumed under the broader Canadian Environmental Protection Act (CEPA) of 1999. These acts set maximum amounts, or air quality standards, for emissions of key pollutants or the presence of key pollutants in ambient air. Both Environment Canada and the provinces are responsible for monitoring air quality as well as for developing, implementing, and enforcing approved compliance plans. As a result of the Clean Air Act and related legislation, Canada has seen major reductions in common air pollutants. Removing lead from gasoline, for instance, reduced lead air pollution by 98% from 1970 levels. Sulphur pollution has also been significantly reduced.

A new Clean Air Act was adopted in Canada in 2006, containing measures to fight smog and greenhouse gas pollution. Under this Act, 2003 emissions of greenhouse gases are targeted to be cut by 45 to 65% by the year 2050, vehicle fuel consumption will be reduced, and there are targets for reducing ozone and smog by 2025. The effectiveness of this Act has been challenged by opposition parties and the public, who have asserted that the Act does little to prevent climate change and more must be done. Canada and the United States have both been criticized globally for their weak positions on controlling greenhouse gases.

The fact that our air is cleaner today than it was in the 1960s—even with a larger population and more industry—is evidence that regulations can be effective. Still, these improvements are costly to industry and farmers, and that cost is usually passed on to consumers. For this reason, many individuals and groups oppose such policies, charging that the restrictions are excessive or that the government goes too far in trying to regulate emissions. Some environmentalists worry that if we weaken or dismantle the environmental legislation that protects our air and water (and by extension, our health and ecosystems), we face the return of a highly contaminated environment, compromised health, and diminished ecosystem function and services.

In addition to command and control regulation, there are other ways to curb pollution. One example is green taxes on environmentally undesirable actions, such as an extra tax on less fuel-efficient vehicles. Tax credits, reductions in the amount of tax one pays in exchange for environmentally beneficial actions, fall on the other side of the spectrum. Tax credits encourage consumers to pursue options that might be more expensive than conventional options (such as the purchase of a hybrid automobile); as more people buy the products, the industries that make them can scale up and bring prices down.

Governments also offer subsidies, free money or resources intended to promote environmentally friendly activities. And with cap-and-trade, also called permit trading, a government or regulatory agency sets an upper limit on emissions for a pollutant on a nationwide or regional level, and then gives or sells permits to polluting industries. Users that reduce their pollution emissions below what their permit allows can sell their remaining credits to other users who exceed their allotments. Over time, pollution levels can be reduced as the cap—or limit—is lowered. A cap-and-trade program successfully reduced sulphur pollution from coal-fired power plants in the United States in the 1990s. A downside to cap-and-trade programs is that pollution can become concentrated in areas where industries choose to buy additional permits rather than reduce emissions.

Technology can also play a big role in improving air quality. To improve indoor air quality we can install air filters and better ventilation systems. To curb pollution emissions from manufacturing, end-of-pipe solutions like scrubbers, filters, electrostatic precipitators, and catalytic converters trap pollutants before they are released. In addition, technology can inspire cleaner methods for extracting energy out of fossil fuels, as is the case with “clean coal” technologies described in Chapter 19. [infographic 21.7]

Mitigating or preventing air pollution costs money, but it is money well spent because it prevents far greater losses down the line—especially in terms of human health. According to a 2003 study published in the Journal of Allergy and Clinical Immunology, the average annual cost of care for an asthma patient in the United States is $4912, with 65% of that going to medications, hospital admissions, and nonemergency doctor visits. The remaining 35% goes to indirect costs like lost time at work. Ultimately, asthma costs Canada and the United States billions of dollars each year. Nadeau, Delfino, and others hope their research helps policymakers realize just how useful curbing pollution can be. “We’re talking about the air we breathe,” Thurston says. “There’s nothing more communal than that.”