A poster in Sheffield
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Giant poster 'soaks up air pollution' in Sheffield

19 May 2014 Last updated at 17:03 BST

A giant poster has been put up in Sheffield to help remove pollution from the air.

Researchers at the University of Sheffield say the banner removes harmful nitrogen oxides: gases you can't see or feel but which have been linked to breathing problems including asthma.

They reckon it can absorb the pollution from around 20 cars a day.

The poster also includes a poem written by Simon Armitage, a professor at the university, called In Praise Of Air.

It'll be displayed on the side of one of the university's buildings for a year.