Both Toto and Lixil are popular in Japan. According to Lixil, some form of warm-water bidet toilet seat is used in more than 80% of Japanese households. But global consumers are proving harder nuts to crack. “Of course there is the giggle-factor,” admits Case. “As Europeans, we’re not used to intimate washing.” That said, Toto have sold over 40 million toilets with washlet wands – which start from around £1,500 ($1,870) – internationally. And beyond the mansions of the mega-rich, they are popular in high-end hotels and restaurants. “It’s one of the last areas that hotels can still be more luxurious [than homes],”says Case. “The washlet experience is quite memorable. There was a restaurant review recently which talked more about the washlet experience than it did the food.”

This may sound like the height of luxury, but there is a more serious need for smarter sanitary technology, and some of these development may benefit the world’s poor as well as the rich. Garv Toilets are free-to-use public toilets in predominantly poor parts of urban India, designed to be ​self-sustainable ​in terms of ​energy usage, ​waste disposal ​and maintenance, with smart technologies such as sensors and radio-frequency identification (RFID) tags integrated into them. Made from gleaming, vandal-proof stainless steel, LED lights and exhaust fans switch on automatically when users open the toilet door. When the visit is over, the same technology automatically activates the floor and toilet pan washing systems. A remote dashboard tracks data on numbers of users and how many times they flushed and used the soap dispensers.

Smarter toilets may also be a crucial element of future healthcare. According to the Toilet Board Coalition, a business network to promote better sanitation, your toilet may even save your life. “They will transform from being dumb buckets that remove waste to smart medical devices that upcycle health data and sync us up with our doctors.”

How far off is that future? According to Floyd Case, Toto is already doing it. “We have sold thousands of toilets for hospitals in Japan, that wash and dry you, but also weigh you and analyse your urine”. In time, he says, domestic toilets will do that too, uploading the data to your smartphone. But they don’t want to rush this technology to market before consumers are ready, he says: “At the moment, people are still wowed by a technology that Japan had 30 years ago.”

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