Deputy Health Minister Dr Lee Boon Chye is not sold on the idea of drinking water straight from the tap.

Instead, Lee advised that water from the tap should be boiled first, as it may be contaminated after passing through old and possibly rusty pipes.

"Water from treatment plants can be drunk straight as it does meet the standards set.

"However, when it is channelled through pipes that are tens of kilometres long before reaching our homes, we don't know if it is safe to drink," he was quoted as saying by Bernama.

On Wednesday, Water, Land, and Natural Resources Minister Dr Xavier Jayakumar said tap water was safe to drink, and that if there are any problems it would be a local issue.

He went on to say that he himself drinks straight from the tap.

The National Water Service Commission (Span) supported the minister, saying water from treatment plans is safe to drink.

An earlier poll run by Malaysiakini showed that 85 percent of the respondents said they would not drink directly from the tap.

A total of 15,600 respondents participated in the day-long poll, which started on Wednesday night.

Several lawmakers also said they would not drink tap water if it was not filtered or boiled first.