Loathe though we are to be scatological, it's time to face faecal facts: the astonishing amount of human excrement on the planet presents a honking environmental challenge.When you think about it, with nearly eight billion of us crimping one out most days, the fact that humans aren't all swimming in the stuff is an impressive log-istical achievement, especially when flush toilets have only existed for 150 years.And despite it being the most normal thing in the world, poos and pooing remains a curious taboo. Unless, that is, you're professor and film-maker Troy Hale, whose latest release (sorry) 'Sh*t Saves the World' is a televisual tribute to all things number two.Ahead of his film being deposited on a UK streaming service near you, we shoot the crap with Troy.Sustainababble is your friendly environment podcast, out weekly. Theme music by the legendary Dicky Moore – @dickymoo. Sustainababble logo by the splendid Arthur Stovell at Design by Mondial. Ecoguff read out by Arabella.Love the babble? Bung us a few pennies at www.patreon.com/sustainababble.MERCH: sustainababble.teemill.comAvailable on iTunes, Spotify, Acast & all those types of things, or at sustainababble.fish. Visit us at @thebabblewagon and at Facebook.com/sustainababble. Email us at hello@sustainababble.fish.