Clean Air Act


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The Clean Air Act (CAA) of 1970, and its subsequent amendments, is a complex, comprehensive law that recognizes the existence of serious air pollution, establishes standards to protect public health and the environment, and authorizes the U.S. Environmental Protection Agency (EPA) to set binding national standards for common and widespread outdoor air pollutants (also called criteria pollutants).

The goal of the Act was to set and achieve National Ambient Air Quality Standards (NAAQS) in every state by 1975. The setting of maximum pollutant standards was coupled with directing the states to develop state implementation plans (SIP’s) applicable to appropriate industrial sources in the state.

The Act was amended in 1977 primarily to set new goals (dates) for achieving attainment of NAAQS since many areas of the country had failed to meet the deadlines. The 1990 amendments to the Clean Air Act in large part were intended to meet unaddressed or insufficiently addressed problems, such as air toxics, acid rain, ground-level ozone, and stratospheric ozone depletion.

The 1990 amendments tightened pollution control requirements in cities that had not reached attainment, mandated a schedule for control technology for all major toxic air emitters, and listed 189 substances (hazardous air pollutants [HAP’s] — also called air toxics) subject to special controls. The EPA can add other pollutants that may present a threat of adverse health effects or environmental effects, but they cannot be listed as hazardous unless they meet certain conditions.

The 1990 amendments also required reductions in acid rain emissions, tighter auto emissions standards, mandated cleaner gasoline and clean-fueled vehicles in the nation’s most polluted cities, and phased out production of chemicals that contribute to depletion of the stratospheric ozone layer.

Key Points

1) Microbeads and other plastic pollutants can linger in the environment for over 50 years, slowly accumulating toxins and working up the food chain.

2) The Great Lakes account for 20% of the world’s freshwater, yet host an average of 17,000 pieces of microbeads per square kilometer. (NPR)

3) More than 11,000 pounds of microbeads are annually added to Wisconsin waterways alone. (Milwaukee Journal Sentinel)

4) Companies like L’Oreal and Johnson & Johnson recently announced plans to phase out microbeads, but it’s unclear whether they will use sustainable alternatives or other plastics.

Public Opinion

  •  78 percent of Americans say the government should limit greenhouse gasses, while 66 percent say they are more likely to vote for a candidate that advocates action to reduce GHGs. — New York Times/Standard poll, 2015
  • 69 percent of adults consider climate change “serious,” an increase since 2008. — New York Times, 2015

  • 70 percent of Hispanics and 56 percent of African-Americans believe the earth is getting warmer because of human activity. — Pew Research Center, 2015

Read more polling results here

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