'Ignorance' of soldering put lead in water pipes

A lack of knowledge about soldering materials on the part of the building industry and the Water Supplies Department caused water at public housing estates and schools to become tainted with lead, top officials said yesterday - though others suggested an attempt to save time and money may also be at fault.

Water supplies director Enoch Lam Tin-sing attributed the safety scandal to ignorance in the industry, but stopped short of saying whether his department should take responsibility for its inability to regulate the use of soldering materials and to detect the high levels of lead.

Secretary for Development Paul Chan Mo-po weighed in, saying: "It is not just the industry that lacks knowledge [on soldering materials], but the Water Supplies Department as well."

Lead levels at nearly 80 times World Health Organisation safety standards were found in water at Kowloon City's Kai Ching Estate, where the scare began in July.

A committee said last week soldering materials were a main cause of the high lead levels.

But Chris Tsang Yiu-fai, assistant professor of science and environmental studies at the Institute of Education, said money and time - and not just a lack of knowledge - were the main reasons behind companies' choice of soldering materials.