NCPA - National Center for Policy Analysis


March 14, 2005

Mercury from China, dust from Africa, smog from Mexico -- all drift freely across U.S. borders and contaminate the air millions of Americans breathe, according to recent research from Harvard University, the University of Washington and many other institutions where scientists are studying air pollution.

  • Pollution wafting into the United States accounts for 30 percent of the nation's ozone, an important component of smog, says researcher David Parrish of the National Oceanic and Atmospheric Administration.
  • By 2020, Harvard University's Daniel Jacob says, imported pollution will be the primary factor degrading visibility in our national parks.

While the United States is cutting its own emissions, some nations, especially China, are belching out more and more dirty air. As a result, overseas pollution could partly cancel out improvements in U.S. air quality that have cost billions of dollars.

Almost every place in the United States has suffered from the effects of imported air pollution, at least occasionally. Some of the most serious impacts:

  • Mercury emitted by power plants and factories in China, Korea and other parts of Asia wafts over to the United States and settles into the nation's lakes and streams, where it contributes to pollution that makes fish unsafe to eat.
  • Dust from Africa's Sahara Desert blows west across the Atlantic Ocean and helps raise particle levels above federal health standards in Miami and other Southern cities.
  • Haze and ozone from factories, power plants and fires in Asia and Mexico infiltrate wilderness spots such as California's Sequoia National Park and Texas' Big Bend National Park, clouding views and making the air less healthy.

Source: Traci Watson, "Air pollution from other countries drifts into USA;Emissions that cross borders could cancel out U.S. efforts," USA Today, March 14, 2005.


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