Friday, May 14, 2021

Being Interviewed on Talking Point shown on Channel 5, 13 May 2021: Do I really need a water filter?

I was approached by the producer for Talking Point to be interviewed for my views on water filters in the context of the home user in Singapore. I ended doing a show-and-tell of three different types of water filtration processes in addition to the interview. Shooting took place a month before the programme was aired on TV though the MeWatch version appeared earlier.


For my part, the programme essentially covered my demonstration of how activated carbon (AC), ion exchange resin and alkaline water ioniser work, as well as my tips to the viewer on choosing a water filter. As per CNA's practice for Talking Point, various subject matter experts were interviewed on pertinent aspects of tap water, water filters and alkaline water. Overall, given the limited duration (20min), the programme provided a rather interesting and balanced take on the controversial issue of water filters for home use in Singapore.

 

Go ahead and watch it on MeWatch!

 

Updated on 28 May 2021: The print version is available now: 

Can filtered water help to prevent cancer? Talking Point gets the answer from a food scientist.
Can filtered water help to prevent cancer? Talking Point gets the answer from a food scientist.https://www.channelnewsasia.com/news/cnainsider/why-filtered-water-may-not-be-as-clean-beneficial-you-think-tap-14901036?cid=FBcna

Why filtered water may not be as clean or beneficial as you think

Updated on 18 May 2021: The YouTube version is available now.


 

This scene with Steven Chia was shot during my filming session with CNA but it was ultimately left out in the final version.
Figure: This scene with Steven Chia was shot during my filming session with CNA but it was ultimately left out in the final version.


10 comments:

Joanne said...

Thanks for sharing your views on Talking Point. May I ask your opinion if boiling tap water before consumption is more beneficial than drinking from the tap directly ? Many people talk about tap water being contaminated by rusty pipes. Does boiling address such worries ? Thanks !

CK said...

Hi Joanne, please refer to my post on this issue of boiling water

VictorOng said...

Hi Adj. Lecturer Kwok,

First of all, thank you for your valuable sharing on CNA Talking Point. I agree with the opinion that one should first decide on - what are the impurities to be removed from the tap water source.

The copper water pipes in my house are more than ten years old and there are signs of green oxidation on the pipe exterior. I suppose this could be CuO and we cannot be sure how the interior of the pipes are affected.

What would your esteemed advice be, on the type of water filter to be used if our primary concern is to remove copper impurities - or even rust as what @Joanne had asked.

Thank you in advance,
Victor Ong
Email: bedoktown@yahoo.com

admin said...

Saw the video about water filters. What can you comment about hollow fiber membrane technology? Is it an effective type of water filter?

CK said...

Hollow fibre membrane technology can be effective if the design and manufacture of the entire module is well executed. They are already used in our water treatment and Newater treatment. As always, when it comes to your health, do purchase from reputable sources as there are many cheap knock-offs floating around in the market.

limsoonhoe said...

Hi CK,

I watched the video on increased contamination from the filter because of the expired carbon filter. I am concerned about the bacteria count in the show.
My 4 filter configuration for the water is: Sediment, Carbon, RO, Carbon. My TDS meter reading for the tap water is between 95-115 ppm and after processing by this filter , its 9ppm. Clearly my RO filter is doing its job & it seems that the RO filter should filter out bacteria. I dont think the TDS meter measures the bacteria that pass through. So should I be concerned that my water quality is not as good because I do not change my carbon filter so often?
Thank you for your help.
Soonhoe

CK said...

You are right - the TDS reading does not account for bacteria. Also, bacterial growth on your expired filters can be a concern. Why should you be drinking possibly bacteria laden water from a water filtration system?

Perhaps it is time to reexamine your reason(s) for using a water filter. Is it achieving its purpose(s) you have in mind? If it does, do the benefits outweigh the potential concerns of bacterial growth on expired filters. This is in addition to the expired filter possibly failing to perform its designated function of removing water contaminants. And if you cannot afford the time/effort/budget to change the filters, then maybe such a water filtration system is not for you.

Mankul said...

Why not add another UV filter module to kill the bacteria?

Mankul said...

Hi CK,

I just watched the documentary. I opine that the water filtration system in Singapore is just too over priced. Add on to the cost of replacing filter cartridges every 6 months, and that also is not exactly cheap.

I am exploring the the DIY route. I find many under the sink filtration system in AliExpress and most of it are 5 stage filtration with RO.

I feel RO is difficult to maintain and your need a storage tank to store water cos filtering through the RO takes a long time. Besides, there's lots of water wastage.

What do you think of this DIY plan:

3 stage filtration involving activated carbon pre-filter + ultrafilter + UV filtration.

I only want to remove metals from presumably old pipes and do not mind the chlorine and fluoride. The UV module is there to kill whatever bacteria that may have lurked inside the filters.

CK said...

Hi Mankul,

To be fair, some (not all) water filters are rather pricey due to the testing and certification that they have gone through.

To me, one big issue with the water filters in the market is the lack of proper certification and testing.

You can certainly DIY your own water treatment train. But how certain are you that the treatment units are capable of removing whatever contaminant you want to remove. Metals also come in various "flavours" so it does not mean a filter that can remove lead can also remove arsenic to the same extent.