Should Singaporeans use water filters? Part 2: Chlorine and other Toxins

In Part 1 of this series on water quality in Singapore and water filters we took a deep dive into the research on adding Fluoride into municipal water supplies. We hope we provided enough information for you to draw your own conclusions as to whether you think this is a good or bad thing. Now we’re going to take a more cursory glance at the other toxins found in Singapore tap water and in particular chlorine.

Chlorinated Water

Why is it placed into the water supply? Easy - because it destroys bacteria, simple as that. And the government doesn’t want an overgrowth of bacteria in your water supply that makes you sick from drinking it. However, are there any consequences of this for your health?

Your Gut Microbiome

Is it a gas mask or a watering can!?
Is it a gas mask or a watering can!?

Well your body is made up of about 10 trillion cells. About 1 trillion of those cells are your own human cells and the rest, 9 trillion, are mainly friendly bacteria that live in places like your gastrointestinal tract (mouth, esophagus, stomach, small intestine, large intestine and colon). These bacteria in our gut ‘microbiome’ do wonderful things like digesting fibre from vegetables and extracting valuable nutrients, helping control our immune systems, keeping us free from diseases and cancers, and even keeping us lean.


So let me ask you this question. If the chlorine in the water supply is strong enough to kill the bacteria in the water supply, is it strong enough to kill the bacteria in our guts? And if it is what are the consequences of that? Let’s have a look at some of the scientific research studies:

Colorectal cancers and chlorinated water

Cancer is the number 1 cause of death in Singapore and colon cancer is the biggest killer of men. How many medical studies are there on pubmed that discuss cancer and chlorinated water? 275. Quite a lot. And here are a couple of snippets:

  • “Published reports have revealed increased risk of colorectal cancers in people exposed to chlorinated drinking water or chemical derivatives of chlorination.” Colorectal cancers and chlorinated water, 2016. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4824718/
  • “These results suggest that exposure to chlorination by-products in drinking water is associated with increased risk of colon cancer.” The association of drinking water source and chlorination by-products with cancer incidence among postmenopausal women in Iowa: a prospective cohort study, 1997. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1380892/
  • “There is no significant association between the incidence of cancer and exposure to chlorinated water”, however they do go on to state, “the control group reported a much higher incidence of gastrointestinal diseases, kidney problems and skin infections.” Chlorinated drinking water, cancers and adverse health outcomes in Gangtok, Sikkim, India., 2009. https://www.ncbi.nlm.nih.gov/pubmed/18476370
There are a ton of scientific research reports on the detrimental health effects of drinking chlorinated water
There are a ton of scientific research reports on the detrimental health effects of drinking chlorinated water

So we'll be honest here in that we did not actually read all 275 studies but if you’d like to, feel free to check them all out by following this link. Out of the three highlighted above the first two clearly draw a link between colon cancer and chlorinated water. However the third one found no significant link between chlorinated water and cancer but they did find a link between chlorinated water and gastrointestinal disorders, kidney problems and skin infections so not completely in the clear!


So why could this be the case? How could chlorinated drinking water be responsible for colon cancer? Well it makes quite a bit of sense for two reasons. The first is that in Singapore we follow WHO guidelines which is basically the US. And a lot of these reports come out of the US where they chlorinate their water to a similar degree to Singapore. In the US colorectal cancer is the third most common cancer diagnosed in both men and women. However colorectal cancer is now the most common cancer in Singapore affecting both males and females. Singapore is a much hotter country than the US so we consume far more tap water magnifying the problem. 

The battle in your gut - don't wipe out your defence with 'friendly fire'!
The battle in your gut - don't wipe out your defence with 'friendly fire'!

The second reason requires a bit more understanding about the gut microbiome so this may be new ground for you. The majority of our friendly gut bacteria live in our lower intestine and our colon and they have a number of different jobs. One of those jobs is to sit around in the mucosal lining to prevent any unpleasant organisms entering your body. Technically everything in your gastrointestinal tract is still outside of your body. However if we nuke the friendly bacteria in our gut with chlorine (and antibiotics) then we are wiping out our surface defence team. The Americans call this, “friendly fire” – they’re really good at it too! So without a surface defence team in your colon you have now created a sterile environment perfect for unfriendly bacteria, molds, fungus, parasites and all sorts of toxins in your poo from entering your body and causing inflammation in your colon. Coupled with the fact that most people consume far too much processed food that bungs them up, then the poo is just sitting around festering even longer than it should.

“What we don’t eliminate, we assimilate!”

Paul Chek


These are not the sole reasons of why we believe colon cancer is so high in Singapore compared to other developed countries. We could also look at much of the country eating incorrectly for their metabolic type, stress induced constipation and a lack of early cancer screening. But as we've already massively deviated off topic here we won't!

Diseases associated with a poor gut microbiome

So getting back to the main topic if we can establish a link between chlorinated water and the destruction of the gut microbiome then we can see what other conditions are linked to having a poorly defended gastrointestinal tract. And here they are:

  • poor digestion
  • chronic heart disease
  • liver disease
  • hypertension
  • Fibromyalgia
  • weight problems and obesity (altering gut bacteria impacts obesity in lab rats)
  • irritable bowel syndrome
  • Ulcerative colitis
  • inflammatory bowel diseases like Crohn's disease
  • rheumatic diseases
  • Rheumatoid arthritis
  • poor sleep
  • ulcerative colitis
  • bloating, abdominal pain and diarrhea
  • diabetes
  • intra-abdominal abcesses
  • kidney diseases
  • cancers like breast (leading cause of cancer in women in Singapore) and prostate
  • weakened immunity
  • Psoriasis
  • mental health challenges
  • unhealthy skin
  • colorectal cancer (leading cause of cancer in men in Singapore)
  • osteoporosis
  • autism
  • allergies

The gut microbiome is a massively hot topic right now and probably one that is producing the most research. The exponential increase in the sale of probiotics is certainly evidence that many people feel strongly about repopulating their gut with friendly bacteria - personally we just like to eat fermented and organic foods to get our bacteria naturally but there are good arguments for both cases. So what next?

Other nasties such as arsenic and cyanide

Yes that’s right there are definitely traces of Arsenic, Cyanide, Cyanogen chloride (as cyanide) and Lead in the Singapore water supply. How do we know this? Because it’s published on PUB’s website here: https://www.pub.gov.sg/Documents/Singapore_Drinking_Water_Quality.pdf


Now all of these are within the WHO’s recommended guidelines, and it is great that Singapore’s PUB is following those but there are two problems with this.

But it looks so innocent!
But it looks so innocent!
  • The firstas we discussed in part 1, is that the WHO seems to selectively ignore certain research reports that tend to show the more detrimental consequences of toxins in our water supply. Presumably this is so as not to be too alarmist to the general population because the cost of removing them completely with reverse osmosis is just way too expensive.
  • And secondly each guideline is written on a per toxin basis. So for example looking at arsenic individually and what it does to the body. This is exactly the same as how the allopathic medical community views the human body – as a collection of individual moving parts as opposed to what we really are – a fully integrated and connected organism. So what are the consequences of drinking very tiny amounts of arsenic + very tiny amounts of cyanide + very tiny amounts of lead and 100 other toxins? We just don’t know, so you can either take your health to the casino, roll the dice and see what fate turns up or you can do something about it by thinking about how to remove these toxins from your diet.
Water filter with a carbon block
Water filter with a carbon block

To be honest you can’t really escape heavy metals and toxins completely as you’ll even find them in good quality bottled water that comes from mountain springs but at least they won’t have the added toxins such as fluoride or chlorine or any unwelcome compounds created in the industrial process of converting sewage or salt water into drinking water.


Ok so in part 3, next weekend, we’ll be releasing our in depth analysis on the best water filters and we’ll also be ranking different types of water including bottled water, glass bottled water, alkaline water filters, carbon based filters, reverse osmosis and many more. It’s the be all and end all guide on selecting the best water in Singapore so you do not want to miss this.




The Levitise Team



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Write a comment

Comments: 5
  • #1

    Jemaima (Tuesday, 25 June 2019 02:54)

    How can you help us as regards to hair loss due to high chlorine in our water? I’ve researched and others experience the same thing.

    Please, my hair loss is driving me crazy despite use of shower filter.

  • #2

    Alex (Sunday, 30 June 2019 23:47)

    Hi Jemaima - that's a great question. Most shower filters are wholly ineffectual because the water rushes through them too quickly for the filter to have enough time to filter out the nasties. It's essential to ask your shower filter supplier for lab testing analysis that shows how effective the filter is with before and after lab tests. If they don't have that then normally they're just all about marketing and less about substance. We have some other good biohacks and suggestions - feel free to give us a buzz on 9634 1940 for more info.

  • #3

    Jonathan (Thursday, 21 November 2019 03:21)

    Why do you say fluoride is toxic?

  • #4

    Alex (Thursday, 21 November 2019 21:09)

    Hi Jonathan, feel free to read part 1 where we look at the science behind fluoride toxicity: www.levitise.com.sg/singapore-water-filters-fluoride/

  • #5

    Champa (Wednesday, 03 August 2022 03:06)

    Hi, are there any measures taken to change this?