Philosophical Tree mural

Italian artist Andreco installed a mural in Bologna, named Philosophical Tree, that uses paint that helps to tackle smog in the city.

Created as part of the Frontier Project, which aims to investigate new forms of street art, Andreco painted the 59-feet-high piece on the side of a five-storey building, using photocatalytic paint that absorbs nitrogen monoxide, otherwise known as smog, in the atmosphere.

via: Springwise