Frank Xu, a 27-year-old office worker, used to blissfully hold the subway ticket in his mouth when he did not want to hold it in his hand. But he stopped doing it after seeing another passenger use the card to clean his teeth.

"I began to have doubts about the hygienic condition of the magnetic cards used on metro lines," said Xu for fearing of contracting a disease.

Not anymore. A new inorganic nanotechnology was recently introduced in the production of magnetic metro ticket cards, making them safer in term of hygiene.

The Shanghai Metro Operation Co. Ltd. said yesterday that new metro cards, including both single- journey tickets and 50-yuan pre-paid cards, will come replete with an antibacterial powder - which employs nanotech.

In fact, some 200,000 antibacterial cards have already been put into operation on RT (rail transportation) No. 1 and No. 2 lines this month. The company plans to upgrade all metro cards over the next nine months to "ensure commuters' health."

"The powder will make the metro cards more resistant to virus, so that passengers can be protected from some infectious diseases," said Shao Weizhong, manager of the fare division under Shanghai Metro, the operator of the city's three existing metro lines.

At present, the number of daily metro commuters has reached some 1 million, while 3 to 4 million magnetic cards are circulated everyday, officials said. Most of them are single-journey tickets, which usually can be used more than 600 times before they are scrapped.

However, under the company's current capacity, only 900,000 cards are manually cleaned daily with alcohol cotton ball or sterilized by ultrasonic equipment, officials admitted.

"Tests have proved that cards inserted with the powder not only resist bacteria, but are very safe to both human skin and the environment," said Shao, adding the new method is already in use in Japan.

Company officials said that even if the subway employs the new cards, workers will still have to do the clean-up in the same old way to avoid misreading caused by stained surface.

Commuters are hailing the move.

"The new card will protect our health better. Furthermore, it will improve Shanghai's image as a global metropolis," said Brenda Yu, 26, who travels daily to her Pudong office.

(eastday.com August 21, 2002 )