Excessive lead has been found in water samples at a Wong Tai Sin primary school built in 1984, marking the first time lead contamination is discovered in an older building. It is the fourth primary school that has been affected by the citywide scandal.

Out of the seven water samples tested at Baptist Rainbow Primary School, three were found to carry lead contents that are over safety standards set by the World Health Organization (WHO), announced the school on Monday.

Two samples from a filtered tap providing drinking water in the staff room contained 15 and 24 micrograms of lead per litre. One sample from a machine in the tuck shop that provides hot water used for cleaning contained 18 micrograms of lead per litre. The WHO safety standard is set at 10 micrograms of lead per litre.

Baptist Rainbow Primary School
Baptist Rainbow Primary School. Photo: Baptist Rainbow Primary School.

Chu Tsz-wing, principal of the school, told Apple Daily that the campus has been in use for 32 years.

He said that there have been many maintenance attempts on the pipes throughout the years, meaning that it’s difficult to trace when the lead contamination began.

Chu said that the filters in the staff room are not due to expire for another six months. The hot water machine was mainly used to clean oil stains on the floor and was not used in cooking, nor in cleaning utensils.

The school has ceased use of the taps that contain contaminated water. It will change the filters in the staff room and continue testing water samples at the school.

In the last two weeks, three primary schools have found excessive lead contents in water samples.

The first case of lead contamination was discovered in July when a water sampling investigation was conducted at Kai Ching Estate in Kowloon City. Eleven public housing estates and seven educational institutes have been affected to date. The majority of these housing estates were constructed in the last decade.

An independent commission chaired by a judge was appointed to investigate the lead-in-water scandal. The commission is expected to report in nine months.

Kris Cheng is a Hong Kong journalist with an interest in local politics. His work has been featured in Washington Post, Public Radio International, Hong Kong Economic Times and others. He has a BSSc in Sociology from the Chinese University of Hong Kong. Kris is HKFP's Editorial Director.