National Geographic News: Plane exhaust kills more people than plane crashes.

There’s a new fear of flying: You’re more likely to die from exposure to toxic pollutants in plane exhaust than in a plane crash, a new study suggests.

In recent years, airplane crashes have killed about a thousand people annually, whereas plane emissions kill about ten thousand people each year, researchers say.

Earlier studies had assumed that people were harmed only by the emissions from planes while taking off and landing. The new research is the first to give a comprehensive estimate of the number of premature deaths from all airline emissions.

“We found that unregulated emissions from [planes flying] above 3,000 feet [914 meters] were responsible for most of the deaths,” said study leader Steven Barrett, an aeronautical engineer at the Massachusetts Institute of Technology in Cambridge.

Airplane exhaust, like car exhaust, contains a variety of air pollutants, including sulfur dioxide and nitrogen oxides.

Many of these particles of pollution are tiny, about a hundred millionths of an inch wide, or smaller than the width of a human hair.

So-called particulate matter that’s especially small is the main culprit in human health effects, especially since the particulates can become wedged deep in the lung and possibly enter the bloodstream, scientists say.

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