Saturday, August 26, 2017

Chlorine in water and water filters to get rid of it

Dear Mr Chen,

I have been reading the articles on your website. Thanks for the many info that you have provided.

Just wondering whether our Singapore tap water is still good enough to drink straight from the tap at this point of time. Is chlorine a health concern, should we at least remove it from the water before consuming it. I'm now looking for a water filtration system.

Your advice on this would be appreciated. 

Thank you


Dear Jennifer,
I am glad that you find my information helpful.
  1. As far as WHO drinking water guidelines go, yes, our tap water is well within their standards and is safe to drink straight.
  2. I have discussed about chlorine in a previous post. In a nutshell, the chances of suffering adverse effects from the chlorine in Singapore's tap water are very low. In fact, your chances of suffering from diarrhea due to contamination from improper food handling and poor hygiene are significantly higher.
  3. However, keep in mind that WHO drinking water guidelines are not omnipotent (see my earlier post). No doubt the guideline values (GV) are designed to be conservative but they are still partly derived with inherent uncertainties. For example, long term health effects e.g. cancer of ingesting small quantities of a chemical continuously are rather hard to determine experimentally so GVs are derived from mathematical models.

    To cut a long story short, you do have a right to be concerned though the degree of risk you are exposed to in drinking this water cannot be quantified easily.
  4. Aesthetic concern. I will the first to admit that I am not a fan of drinking water chlorinated by "chlorine tablets" or powder. It tastes too much like swimming pool water to justify me drinking it for more than a few days.

    When I compare the taste of our tap water with bottled distilled water, I do detect a difference but nothing like the "swimming pool" water above. Perhaps I am the lucky one as I know of people who are more sensitive to the taste of chlorine in our tap water. And if you are one of them, by all means, do something about it.
  5. At the end of the day, I guess it comes down to whether the concern about drinking our chlorinated water is affecting you adversely. If so and if you can afford the cost of a filter (plus the cost and time for replacements), please go ahead to get one. If nothing else, the peace of mind is well worth it!
  6. If your concern is only about chlorine, I suggest getting a good (i.e. ideally with NSF/ANSI certification to remove chlorine. Refer to 1, 2, 3 for more info) filter incorporating activated carbon.
  7. One recommendation is either a countertop or undersink filter housing from Arkwater incorporating the Ultracarb filter element which can remove chlorine and quite a few other contaminants. (Let me reiterate that I do not derive any benefit from the sales of Arkwater.)  Obviously, there are many other brands and models that can do the same thing so feel free to look around.
Figure: Arkwater's countertop model. Stainless steel. The Ultracarb filter element is housed inside.

Figure: Arkwater's undersink model. Stainless steel. The Ultracarb filter element is housed inside

Figure: P&G PUR satchet contains a chlorine compound and a coagulant. Made in Singapore! Pretty effective but the taste is simply unforgettable and not something to be taken over long term


Jennifer said...
This comment has been removed by the author.
Germisep said...

Hey CK,

Some of the people do have problem with consuming chlorinated water. I usually prefer using chlorine tablets to disinfect the water but my family felt differences in taste of it so I filtered it using activated carbons. They work amazing!