The Japanese government is calling on people to stockpile toilet paper in case of a major earthquake.
Most people, it says, think of water and food as emergency supplies, but neglect this other essential. And, says Toshiyuki Hashimoto, an industry ministry official in charge of paper products, "After running out of toilet paper, people start using tissue, and that could clog up precious workable toilets."
Concern is made all the greater by the fact that 41% of the country's toilet paper supply comes from Shizuoka in central Japan. It's one of the country's most earthquake-prone areas, and seismologists predict that it has an 80% chance of suffering a major quake in the next 30 years.
According to Hashimoto, if such a quake did hit, the country would suffer a nationwide shortage of toilet roll for a month.
As part of its warning, the government has worked out just how much toilet paper people need - although it may be neglecting the effects of sheer terror on its citizens' digestive systems.
Apparently, a family of four should be able to survive for a month on a six-roll pack, which seems a little stingy to us. Manufacturers have even created a tightly rolled, 150-metre-long, single-layer toilet paper that lasts more than twice as long as an ordinary roll.
"Along with food, toilet paper was among the first items that disappeared from store shelves during the disaster, even outside disaster-hit areas," says Hashimoto. Loo roll has now been added to the list of essential supplies on the government's Basic Disaster Management Plan.
While in many countries toilet paper is seen as unnecessary - what else is your left hand for? - consumption is increasing around the world. In Japan, more and more needs to be imported: almost 120,000 tonnes in 2012.
And it isn't the first country to realise just how important toilet paper can be. The Venezuelan government, for example - plagued by the fact that cheap commodity prices encourage smuggling - last year sent in troops to seize a toilet paper factory to counter a desperate shortage in the country.
The last word must surely go to the South China Morning Post, which publicised the call to stockpile toilet paper yesterday as part of the country's Disaster Prevention Day. "Stock up on toilet paper for when disaster rumbles", it urged its readers: a message we could all take to heart.
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