People wear masks to protect against air pollution and dust in Beijing
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Research suggests air pollution in China shortens lifespan

9 July 2013 Last updated at 20:02 BST

In China, the lives of millions of people have been shortened by government attempts to help them heat their homes.

This is according to researchers who say people in northern China who were given free coal for several decades, are dying five years earlier on average, because of air pollution.

Martin Patience reports from Beijing.