Skip to content

Press Release

Update on investigation into unsatisfactory water samples of aircraft

29 June 2015

The Port Health Office (PHO) of the Department of Health (DH) today (June 29) reported an update of the joint investigation with Cathay Pacific Airways Limited (CX), the Airport Authority Hong Kong (AA) and Hong Kong Aircraft Engineering Company Limited (HAECO) following unsatisfactory laboratory testing results of water samples collected from the aircraft of CX.

"A total of 39 samples were collected during the PHO's investigations. Upon the testing and microbiological investigations by the Public Health Laboratory Services Branch of the Centre for Health Protection of the DH, Escherichia coli (E. coli) was not detected in any of the water samples and hence there is no immediate public health risk to travellers and crew members," a spokesman for the DH said.

The microbiological investigation results are shown below:

(A) Water filling points

Regarding the airport, five water samples and five environmental swabs were collected from all five water outlets of three water filling points. Coliform bacteria were not detected in any of the five water samples while food-poisoning organisms were not found in the environmental swabs, suggesting the water source is free from contamination. As of today, the Centre for Health Protection did not receive any food poisoning case related to consumption of water in aircraft.

(B) Water tankers

As for the three ground handling companies, 19 water samples were collected from 19 water tankers, including:

  • Eleven water samples were collected from eleven water tankers operated by HAECO. Trace amount of coliform bacteria were detected in one of them (it was one of the four water tankers which had filled the 14 affected aircraft) at a level of one colony-forming unit per 100 millilitres (cfu/100ml). Coliform bacteria were not detected in the remaining ten water samples from ten water tankers.
  • Two water samples were collected from two water tankers operated by Pan Asia Pacific Aviation Services Limited. Trace amount of coliform bacteria were detected in one of them at a level of two cfu/100ml. Coliform bacteria were not detected in the water sample of another water tanker.
  • Six water samples were collected from six water tankers operated by China Aircraft Services Limited. Coliform bacteria were not detected in all water samples.

(C) Aircraft

Six water samples were collected from three aircraft operated by three other airlines and no coliform bacteria were detected.

Cleansing and disinfection of water tanks of all 14 affected aircraft was completed. PHO is working closely with CX to examine the water quality of the affected aircraft after disinfection.

"There is no evidence at present to suggest a contaminated water source at the water filling points of the airport. However, the very trace amount of coliform bacteria detected in the two water samples from water tankers suggested a suboptimal standard of water quality, which may be likely contributable by the hygienic condition of the water tankers," the spokesman said.

Coliform bacteria are not a single species of organism. They are a group of closely related, mostly harmless, bacteria which live in soil, water and the gut of animals. Coliform count is a hygienic indicator and a high level of coliform count generally indicates an unsanitary condition.

The PHO met with the Water Supplies Department (WSD), the AA and the three ground handling companies today to follow up the findings. The ground handling companies concerned has suspended operation of the two water tankers tested positive for coliform bacteria and will conduct thorough cleansing and disinfection. Testing will be arranged after disinfection accordingly.

"We will work with airport stakeholders to step up regular cleansing, disinfection and surveillance of water tankers. The WSD and the AA will continue to closely monitor the quality of water source at the airport. When there is any irregular results noted in routine water surveillance by airlines and ground handling companies, prompt notification to AA and PHO is required," the spokesman added.

A letter to all airlines will be issued to inform them of the latest findings.

29 June 2015