Exclusive: Annual consumption of plastic bottles is set to top half a trillion by 2021, far outstripping recycling efforts and jeopardising oceans, coastlines and other environments
 A file picture dated 13 April 2010 shows a boy from Senegal walking along a polluted beach strewn with predominantly plastic bottles in the village of Ngor, Dakar, Senegal. Photograph: Nic Bothma/EPA