Pop-up global art project turns air pollution into street art from London to New York City in honor of Earth day.

Air pollution has never been associated with beautifying a city, but that notion is about to change, albeit in a small, artistic way. Thanks to a project by a group of international artists, their sponsor Tiger Beer, and the ingenuity of Graviky Labs’ co-founder Anirudh Sharma, public spaces in Singapore, New York, Berlin, and London will feature creative murals and canvases painted with ink derived from smog.

This is made possible by Air-Ink, Sharma’s invention born out of the MIT Media Lab, in which carbon emissions are collected, purified, and converted to a rich, water-resistant black ink that can be used in pens, markers, and screen printing. A 30 ml bottle of Air Ink negates 45 minutes of pollution, collected from a car exhaust pipe.

“Growing up in India and experiencing the effects of air pollution first-hand motivated me to think of ways to turn this harmful pollution into something useful,” New Delhi-born Sharma said. “Purified, safe ink.”