Cigarette butts are probably the grossest thing that you just see all over the place, and it probably should not surprise you to learn that they are also a very problematic pollutant. Citylab has an interesting profile one one company, TerraCycle, which has developed a way to recycle discarded butts and turn them into plastic. "There's nobody else who has been recycling cigarette filters," says the company's global vice president of research and development. TerraCycle has its detractors too, who say that they are only addressing a symptom of the problem, not the cause, and that by allowing cigarette manufacturers to partner with them the manufacturers are being let of the hook for the damage they are doing. The whole thing is worth is a read.
• Turning Cigarette Butts Into Something Useful [Citylab]