Only days after Tokyo and Beijing patched up years of bitter division, the new détente could be jeopardised by a spate of exploding lavatories in Japan that is being blamed on shoddy Chinese workmanship.

In a setback for the high-tech Japanese lavatory industry, more than 180,000 Washlet units are being recalled because they may burst into flames.

Dozens have already done so and the recall itself — formally announced in every big Japanese newspaper — has triggered an understandable panic in bathrooms up and down the country.

The scandal centres on Toto, the largest Japanese manufacturer of electronically controlled lavatories and the company responsible for the notorious Washlet — a unit with an automatically warmed seat and a function that washes and then blow-dries its user’s fundament.

In a move destined to sour business relations across the East China Sea, Toto is now blaming substandard Chinese parts for the debacle. Although beloved by Japanese themselves, the controls of the Washlet — a formidable armrest bristling with a baffling array of multicoloured buttons, lights and dials — have long been the bane of unsuspecting foreigners. The problem most usually arises from a confusion between which of the flush and bidet controls is correct.

The machine’s various functions require it to remain connected to the electricity mains around the clock. In certain models, a stretch of poorly insulated wiring can become scratched, short-circuit and play havoc with the heater that warms the bidet water to a precise temperature. This can cause the Washlet’s plastic seat first to melt, then ignite.

Inspired to terror by uncompromising evening newspaper headlines such as “Toto to fix buttock-scorching bidets”, nearly 50,000 Washlet owners yesterday jammed the company’s information lines. Although no injuries have yet been reported in connection with Toto’s combustible conveniences, many “near-miss” victims have come forward to describe horrified disbelief as their lavatories unexpectedly set themselves ablaze.

Now, with the atmosphere of fear increasing, a pair of darker secrets has come to light. The first is that the fault with the units may originate in Shanghai. Seven years ago, and without informing its customer, one of Toto’s key component makers shifted its factory from Japan to China.

All the reported incidents, a Toto spokesman said, occurred after its supplier switched the location.

It emerged yesterday, however, that Toto may not have been a wholly innocent victim of shoddy Chinese workmanship. It engaged in an attempt to cover up the incidents for several months before being forced to go public for the sake of Japanese posteriors.

Toto, which sells about three million high-tech lavatories every year, was yesterday joined in humiliation by its closest rival, INAX, whose management also admitted that it had failed to report properly a series of incidents involving its products.

The Toto and INAX scandals come amid a series of embarrassments for corporate Japan, which depends heavily upon its reputation for high product quality. Sanyo, Sony, Toyota and a variety of other household names have recently been embroiled in product recall incidents.

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