NCPA - National Center for Policy Analysis


April 3, 2008

Everyone agrees that air pollution from U.S. manufacturing has declined significantly in recent decades.  But has America simply offshored its dirty industries and boosted imports of polluting products, as many globalization critics claim?  Not according to research by Georgetown University economist Arik Levinson.

The good news, says Levinson, is that most of the pollution reduction over the past 30 years has come from changes in technology, rather than from changes in imports or changes in the types of goods produced domestically.

  • Criteria air pollutants collectively declined 58 percent from 1972 to 2001, despite a 71 percent increase in manufacturing output.
  • The cleanup was accomplished by changing the mix of goods produced and by altering the technologies used to produce those goods.
  • For a typical pollutant, technology accounts for a large majority of the cleanup.

Moreover, although some of the improvement is due to the changing composition of industries, that change can not be explained by increases in imports:

  • For the typical pollutant, increased international trade explains at most half of the pollution reductions from composition changes in U.S. manufacturing.
  • Those composition changes in turn explain less than half of the overall reduction in U.S. manufacturing pollution.

Source: "The Myth of Offshoring Pollution," The American, March/April 2008; based upon: Arik Levinson, "Technology, International Trade and Pollution from U.S. Manufacturing," National Bureau of Economic Research, Working Paper No. 13616, November 2007.

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