【明報專訊】TESTS have found unacceptably high levels of lead in tap water samples taken in two other public rental housing (PRH) estates. This shows the lead water affair tends to become more extensive. The authorities have tentatively concluded that, like those collected at Kai Ching Estate, the samples are with an unacceptably high lead content because water-pipe welds contain lead. Even so, it is clear from what has happened that the departments responsible for such matters have failed to carry out adequate or effective control. It therefore seems totally necessary for the Housing Authority to appoint a task force to look at materials, construction, prefabricated parts and inspections at various stages. It is hoped that it can by doing so remedy the situation.