PIPE DREAMS: The Urgent Global Quest to Transform the Toilet

Most of us who venture abroad have been intrigued by the design of other nations' toilets. Award-winning science writer Chelsea Wald has made a global study of what people do with their waste matter, and the result is alternately surprising, amusing, informative and terrifying. Before flush toilets, humans were often loath to waste urine, using it for a range of purposes including fertiliser, as a setting agent for plant dyes, and for the tanning industry. The Roman emperors Nero and Vespasian levied taxes on public urinals, and Madonna swears by it as a cure for athlete's foot. 100 trillion gallons of wastewater are produced daily worldwide, and in some countries it is diverted as irrigation, with purple being the colour for wastewater pipes to avoid mistakes resulting from colour blindness. Urine and faeces are also a major resource for medical research. The Massachusetts Institute of Technology in 2018 addressed a crisis of deaths from opioid addition by lowering a biobot into selected manholes to analyse the waste not only for opioids but also the overdose-reversal drug, identifying which areas should be targeted for opioid reduction and where the reversal programmes were active. The modern toilet was pioneered in Britain in the late 16th century, when toilet bowls with standing water were invented to reduce the stink. In 1775 a valve was introduced to release the water and waste, and by the late-19th century the toilet had become the single-piece ceramic self-cleaning mechanism that we would recognise today. Different designs of toilet are described, including the inventions of the legendary Thomas Crapper. As toilets gained in popularity, sewage became an increasing problem, resulting in the famous "great stink" of 1858 which prompting the creation of London's sewer system, the model for European and American developments. Worldwide, though, less than half the world's population even now have what experts call "safely managed sanitation". Read about a compost toilet in Haiti, a plant in the Netherlands that salvages toilet paper from sewage and a toilet seat that analyses signs of illness in your poop. Finally the author discusses "lavatory humour" and the psychology of talking about defecation. 282pp, illustrations.