To make sure the plastic bottles she and her husband collect at a small waste station in Hunan are fit for recycling, Ms. Liu Jingyi removes the paper labels from each one with her bare hands and painstakingly sorts them by colour. Over the past ten years, she and her husband, Mr Zhu, have recycled 9 million plastic bottles and more than 20 tonnes of plastic material in order to fund their two sons’ university education.