Walking is good for the environment. But it can be even better if you wear the right clothes. A new detergent turns your clothes into wearable air purifiers. The detergent company Catalytic Clothing has harnessed the same titanium dioxide nanoparticle technology that is used in smog-eating roads and skyscrapers, and applied it to clothing. The detergent adds a safe layer of titanium dioxide to your jeans and according to researchers from the London College of Fashion, removes 80% of the nitric oxide, a major greenhouse gas, from the air directly around the wearer.