The solutions to the problem of plastic pollution and plastic waste lie in many directions. A global plan to stop littering will go a long way. But human behaviour change often needs some economic intervention. One idea by the UK government and many others around the world, is to give a little financial incentive in the form of deposits on plastic bottles, or taxation on single use plastic like coffee cups, food wrapping and plastic bags. Mark Miodownik investigates some of the scientific solutions such as alternatives to petrochemical plastic using microbes or plant materials, clever waste sorting technologies to help make the process easier, even using less plastic. And he hopefully untangles some of the confusing messages about plastic and comes up with ways to be plastic smart. Producer: Fiona Roberts First broadcast on Tuesday 29 May, 2018.