A 3m (10ft) high diesel soot particle has been installed in the centre of Bristol to show city dwellers a large version of what they are breathing in.
The sculpture, which is three million times the size of a soot particle, was created by Bristol-based Luke Jerram.
The work, called Inhale, has been installed in Millennium Square as part of the city's Festival of Nature.
Mr Jerram said he hopes it will spark conversation about the health impacts of poorly-designed cities.
Made out of coal, pyrite and calcite, the sculpture's materials reflect the actual make-up of a soot particle - black carbon, metal residue from exhausts and brake pads and chipped road surface.
Designed to make air pollution visible to the public, the one micron soot particle has been enlarged to about 3m tall.
Mr Jerram, who was behind Bristol's 2014 giant water slide, the globally successful street pianos and the Museum of the Moon, said his sculpture was intended to spark conversations.
"The artwork was in part inspired by the recent VW diesel [emissions] scandal and a friend, whose young child suffers from asthma," he said.
The artwork, commissioned by the University of the West of England (UWE), was described by Professor James Longhurst as making "invisible air pollution visible".
"Air pollution is a major cause of ill health and this impressive sculpture will encourage debate and I hope action on the impact of air pollution on public health," he said.
Inhale will be on display as part of the UWE Bristol public engagement on 9 and 10 June.