The recycling revolution and the whereabouts of our waste are hot topics this week as David Butler describes a new technique for recycling water, Rebecca Weymouth lifts the lid on what happens to our domestic waste, Peter Barham reveals why plastic is so difficult to recycle, and Richard Thompson discusses how waste plastic threatens the environment. In Kitchen Science Derek turns old chip oil into biodiesel, and from making fuel to running on empty, Anna Lacey asks Andrew Prentice how humans cope with famine. Like this podcast? Please help us by supporting the Naked Scientists)