Printing ink, especially the basic black ink found in printers and copy machines just about everywhere, is a cash cow for some companies, but one scientist believes we can make it easily enough with the soot present in the air of polluted cities. Anirudh Sharma, a graduate of the MIT Media Lab, says that companies such as HP and Canon make some 70% of their profits by selling printer ink cartridges made using “complex chemical procedures” at a 400% margin, but his invention, if perfected and scaled up, might take that model and turn it on its head.

According to Sharma’s website, his Kaala-printer contraption (kaala means black) was conceived of during a trip to his home country of India, where heavy smog and soot are an everyday occurrence in the crowded cities, which led him to wonder if the soot in the air could be repurposed into ink for printers.

Sharma built a demo device that can pull soot from a burning candle and accumulate it in a modified syringe, which is then used to fill a modified HP inkjet cartridge with a mixture of the soot, vodka, and olive oil. When the cartridge is integrated with an Arduino ink shield, this decidedly low-tech ink can be used to print at a 96 dpi resolution.

According to Tech Insider, Sharma says the non-uniform ink from his research project “could still be blacker,” and the soot-based ink would need to pass toxicity standards before it could be on the market, but he believes that with some work, it could “become as good as the printing ink HP sells.” He estimates that the output of a late-model diesel engine could produce enough carbon to fill an ink cartridge in about 60 minutes [insert obligatory VW diesel joke here], and a chimney in about 10 minutes.

Check out his post on the Kaala soot printer at his website.