Since October, Philadelphia had been sending half of its recyclables to an incinerator in Chester, which surprised and upset some residents. As of Monday, that practice officially ended. Why was the city burning its recyclables in the first place? The answer takes us from your kitchen to China. The Philadelphia Inquirer’s Frank Kummer explains on this update episode of The Why, and WHYY’s Alan Yu has one company’s answer to the plastics problem with a pilot program launching later this month.