The most pervasive form of plastic pollution on Earth isn’t plastic bags or even plastic straws. It’s cigarette butts. Every year, an estimated 4.5 trillion cigarette butts, containing plastic filters, are littered by the 76 to 84 percent of smokers who toss the ends of a smoke rather than disposing of them into a trashcan or ashtray. The choice to pollute with a cigarette butt may seem small, but it brings repercussions over time. Most recently, scientists from England’s Anglia Ruskin University discovered that cigarette butt litter can significantly harm plants. [...]