WHO chief: Air pollution link to 600,000 deaths in children
6 March 2017 Last updated at 00:29 GMT
The director general of the World Health Organization has said air pollution is "one of the most pernicious threats" facing global public health today and is on a much bigger scale than HIV or Ebola.
Dr Margaret Chan told the Today programme that poor air quality was having a disproportionate impact on the young.
She said indoor and outdoor pollution was linked to the deaths of hundreds of thousands of children each year.
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