Water is declared safe after bug alert

PUBLISHED : Tuesday, 10 January, 2012, 12:00am
UPDATED : Tuesday, 10 January, 2012, 12:00am


The water at the new government headquarters in Admiralty is safe to use, a microbiology specialist says, after tests conducted following disinfection found all but one of more than 200 samples free of a potentially fatal bacteria.

The assurance came as the health minister announced five more locations, including the toilet of the chief secretary, had tested positive before the disinfection.

No abnormalities were detected in the potable water system, said Yuen Kwok-yung, the University of Hong Kong's head of microbiology. Yuen said hyperchlorination, the use of chlorine to disinfect water, had reduced the bacterial count to a low level.

'We have determined that the water at Tamar is safe,' he said.

A team formed by HKU and Queen Mary Hospital took 227 post-disinfection samples from showers and taps last week. Yuen said the sample that tested positive contained a 'very low' concentration of Legionella pneumophila - 0.128 bacteria per millilitre of sample. Such a result can be due to dead bacteria.

Doubts were cast on the cleanliness of the water at the headquarters after education minister Michael Suen Ming-yeung was diagnosed with legionnaires' disease last month. The bug was found in his toilet and elsewhere.

Contaminated water was also found in the chief executive's office; the private toilets of several bureau secretaries; a first-floor kitchen in the Legislative Council building; the canteen on the first floor of the government offices building; and a cafe outside the east wing.

Since then the toilets of the chief secretary and the secretary for commerce and economic development, and toilets in the east wing, had been found to be contaminated, Secretary for Food and Health Dr York Chow Yat-ngok said.

Chow had left the tap water in his private toilet running for 15 minutes, presumably before using it for the first time. But he had not shared this tip with Suen, he said.

Asked why, Chow replied: 'This is my habit. I don't start a conversation by talking about showers when I meet people.'

He said there was no evidence supporting allegations that the government had rushed to finish the complex.

Yuen said legionella living in water and soil invariably contaminated the inner surfaces of plumbing during construction of a building. As the water tended to stagnate before the system went into regular use, the bacteria could multiply, he said.

The professor said regular monitoring of the water system was not warranted unless another case of human infection surfaced.

Chief Executive Donald Tsang Yam-kuen mentioned last week that there might be a need to require certain new buildings to undergo tests for legionella before they were occupied. A spokesman for the Chief Executive's Office said yesterday that it was 'still premature' to say whether there was such a need as an investigation was continuing.

Leung Koon-kee, director of architectural services, said the medical experts' analysis of the incident meant there was no need to introduce such building guidelines.

The canteen was closed again yesterday after it was closed for a day last Wednesday. The management of the administration wing said the water system in the canteen had been sterilised and the water was safe to drink.


The number of samples a medical team took after the disinfection campaign in the government headquarters