Every year, more than four to five million people die due to exposure to outdoor air pollution around the world. This petri dish that you are looking at contains approximately 20 minutes' worth of pollution captured off a pyrolysis plant. This is PM 2.5. These particles -- you can see it right now, but when they're out there in the air, you won't see them. These are so tiny that our lungs -- our bodies cannot filter them, and they end up in our bodies -- give us asthma and lung cancer if not treated in the right time. On a trip back to India, when I was a student in 2012, I took this picture. This picture stuck in my head. On one side, you see this exhaust of a diesel generator, the same generator which is a sign of human progress, which is a sign of rapid industrialization and what we have become as a society in the last 100 years, generating energy. But on the other side, you see this very interesting triangular, black-colored swatch, that is produced by the same residual particulate waste created by the emissions of the generator. Now, this picture gave me an idea and got me thinking about rethinking both pollution and inks, because it was making that black-colored mark. Now, the reality is that most of the black ink that we use conventionally is traditionally produced by conventionally burning fossil fuels in factories. There are factories around the world that are burning fossil fuels to produce carbon black, to make black inks that we use on an everyday basis. But given that millions of liters of fossil fuels are already being burned out there by our cars, our engines and our exhaust out there, what if you could capture that pollution and use it to recycle and make those inks? I decided to give this experiment a shot. I went back to my lab back in Boston and conducted a small experiment. In Boston, I couldn't find much pollution to play with, so I resorted to using a candle. This was an experiment. I burnt a candle, built this contraption that would suck in that candle soot, mixed it with some vegetable oil and vodka, because to a DIY hacker, these were really easily available. (Laughter) And after mixing them, you could churn out a very rudimentary form of ink that would go into a cartridge, and now you could print with it. This was my "Hello, World!" of experimenting with printing with pollution. This is the same pollution that I showed you in the petri dish, which is the result of any fossil fuel that is being burned out there. In 2015, I decided to take this experimentation forward and set up a lab in India to work on the capture and recycling of air pollution. In the good times, the lab used to look something like this. But experimentations were not always controlled, and disasters happened. And while experimentation would happen, the lab would end up looking something like this. Well, we knew where we wanted to go, but we were not sure how exactly to reach there. The passersby who used to go by that lab through that building used to, at times, think, "These guys are making bombs in there," because there was too much fire, wires and smoke in the same vicinity. (Laughter) We decided, let's move to a garage and take experiments forward. We took a garage, and during the early stages, we were driving around Bangalore with contraptions like these. This is an early-stage prototype. Imagine the looks people gave us, "What are these cars driving around doing?" This is an early-stage prototype of our system that would capture pollution that is being released from a conventional diesel-based car. This is an early stage of the technology. We advanced the technology and created this into this version that would capture pollution from static sources of pollution, like a diesel generator. If you see, all the fumes disappear as soon as you turn this machine on. Without affecting the performance of the engine, we are able to capture 95 percent worth of pollution released from the diesel generator. This is the particulate matter that we are talking about that we capture, in this case, within three to four hours of operation of a generator. And while our experiments and our research was advancing, a very big company, a very big brand, approached us and said, "We want to take this idea further with you guys, and take this further in a very big celebrated form." They said, "Let's do a global art campaign with the inks that you are making off this pollution." I'll show you what the ink looks like. So, this pen is made by recycling 40 to 50 minutes of that car pollution that we are talking about, the same pollution that is in the petri dish. And it's a very sharp black that you can write with. So I'm going to write ... PM 2.5, that's incorrect. So this is a very sharp black that is generated by the same pollution. After much work on the lab-level research, we got an offer from a big corporation to do a very big trial of this idea. And it happened to be a brand, and we didn't think twice. We said, "Let's go ahead." Inventing in the lab is one thing and taking ideas and deploying them in the real world is completely another. During early stages, we had to resort to using our own houses and own kitchens as our ink-making factories, and our own bedrooms and living rooms as the first assembly line for making these inks. This is my cofounder Nikhil's own bedroom, that is being used to supply inks to artists all around the world, who would paint with AIR-INK. And that's him, delivering AIR-INKs to the ports so that the artists around the world can use it. Soon, we started seeing that thousands of artists around the world started using AIR-INK, and artworks started emerging like this. Soon, thousands of black-and-white, pollution-made artworks started emerging on a global scale. And believe me, for a group of scientists and engineers and inventors, there was nothing more satisfying than that the product of their work is now being used by some of the finest artists around the world. This is the cover of "Contagious" magazine last year, that was done by using the same ink that we made back in our labs. This is a famous painting by the British artist, Christian Furr, who painted it for the song "Paint It Black" by The Rolling Stones. Now, there's more to this pen and this ink than just the popular and pop-culture artworks. And now our goal is to create a company that can actually make some black money -- I mean, just money -- (Laughter) and high-quality printing processes and inks that can replace the conventional black inks that have been produced for the last thousands of years around the world. Soon after our growing popularity and artworks around the world, we started facing a very different kind of a problem. We started getting spammed by polluters, who would send us bags full of pollution to our office address, asking us, "What can we do with this pollution?" Our lab back in Bombay right now has pollution samples that have come from London, from India, from China, you name it. And this is just the beginning. This polluter sent us this specific image, asking us that these are all bags filled with PM 2.5, and can we recycle it for him if we paid him some money. Well, what would he have done if we did not take that pollution? He would probably find a nearby river or a landfill and dump it over there. But now, because we had the economics of AIR-INK figured out on the other side, we could incentivize him to give us this pollution and make inks from it, and turn it into even more valuable products. Now, pollution, as we all know, is a global killer. We can't claim that our ink will solve the world's pollution problem. But it does show what can be done if you look at this problem slightly differently. Look at this T-shirt I'm holding right now. This is made from the same AIR-INK I'm talking about. It's made from the same pollution that is inside this petri dish. And the same pollution we are all breathing in when we are walking outdoors. And we are on our way to do better than this. Thank you very much. (Applause)