It Cleans Drinking Water - But Is It Safe?

Why Is Chlorine In Our Water In the First Place?

Why would we put a chemical, like chlorine, in water in the first place?

The answer is pretty easy to come up with.

Chlorine makes water safe to drink (at least as far as water-borne pathogens are concerned), as it kills pathogens on contact when it interacts with organic matter in water.

The issue people are flagging is that when it does kill organic material, it forms byproducts, most notably trihalomethanes (THMs) and haloacetic acids (HAAs).

These are the compounds that tend to show up in research discussions, not chlorine itself.

Some observational studies have linked long-term exposure to higher levels of these byproducts with certain health risks, including bladder cancer and potential reproductive effects. 

The concern is usually not chlorine itself, but what happens when it reacts with organic material in water. This process forms compounds called disinfection by-products, including trihalomethanes (THMs). These are regulated because of potential long-term health effects, and that’s where most of the modern discussion comes from.

Some of the stronger human data we have is observational. Studies have found associations between long-term exposure to higher levels of these by-products and an increased risk of bladder cancer. That doesn’t prove direct causation in every case, but it does suggest this is a real area of concern worth understanding (DOI:)

Another piece that is often overlooked is how exposure occurs.

Most people think only about drinking water, but research shows that exposure can also occur through inhalation and skin contact, particularly during hot showers. Warm water increases the release of volatile compounds into the air, which are then inhaled 

In practical terms, that means a long, hot shower can change your exposure profile more than people expect.

Pool environments bring in another layer. Chlorine reacts with sweat and organic material to form chloramines, which are known to irritate the eyes, skin, and respiratory tract. This is especially noticeable in indoor pools with poor ventilation.

From a clinical standpoint, most people tolerate chlorinated water just fine.

But some don’t.

I tend to see issues show up in a few predictable ways: dry or irritated skin, worsening eczema, or respiratory sensitivity, especially in people with frequent pool exposure or higher overall environmental load.

So the question becomes: what’s practical to do about it?

Easy, Proven Ways to Minimize Negative Health Impacts of Chlorine

For drinking water, filtration is one of the more evidence-supported options. Certain systems—particularly reverse osmosis and well-maintained activated carbon filters—have been shown to significantly reduce disinfection by-products (DOI:). Not all filters perform equally, and that’s an important detail.

For bathing and showering, I think more in terms of reducing intensity rather than eliminating exposure. Slightly cooler water, shorter showers, and good ventilation can all make a difference. This lines up with what we know about inhalation exposure increasing with heat and steam

When it comes to skin, the focus is simple and grounded.

While your skin is “waterproof,” it doesn’t mean that chlorine that comes into contact with the skin won’t do anything.

Chlorinated water can be drying and disruptive to the skin barrier, particularly with repeated exposure. In dermatology, barrier repair, using gentle cleansers and moisturizers, is a well-supported approach to managing irritation and maintaining skin resilience 

Respiratory effects are more individualized.

Some research, particularly in children, has found associations between chlorinated pool exposure and asthma or airway sensitivity. This is observational data, and not without debate, but it’s enough that I take symptoms seriously when they show up in that context. 

What I don’t emphasize in practice is aggressive “detox” protocols.

There isn’t strong human evidence that supplements specifically counteract chlorine exposure. I find it more effective and more realistic to reduce unnecessary exposure and support the body’s natural barriers and systems.

That tends to be the steady path forward.

Chlorine is not simply a problem to eliminate.

It’s part of why our water is safe. But it’s also reasonable to understand how exposure works, where it adds up, and how to adjust when someone is more sensitive.

Most of the time, better outcomes come from that middle ground, where we’re paying attention, making practical changes, and working with the body instead of against it.

And by far, if you’re going to address it anywhere, drinking water is the number 1 way to get fast and sustainable results.

A simple reverse osmosis system won’t just help get it out of your water; it will get rid of tons of other harmful contaminants, too.