Chlorine vs. chloramine: what's actually in your shower water.

If your skin feels tight after a shower, your scalp itches, or your color fades faster than it should, the water itself is the variable most routines never check. And what's in that water comes down to how your city disinfects it — with chlorine, or increasingly, with chloramineChlorine mixed with a little ammonia. Water companies use it because it stays active longer in the pipes.. They behave differently, they feel different on skin, and one is meaningfully harder to filter than the other.

Why tap water is disinfected at all

Disinfection is one of the great public-health wins of the last century. Adding a chemical residual to municipal water keeps it free of waterborne pathogens all the way from the treatment plant to your tap. The EPA and CDC consider both chlorine and chloramine safe to drink at regulated levels, and that's not in dispute.

The catch is that the same residual that protects the water in the pipe is still active when it lands on your skin and hair. Chlorine and chloramine are oxidizersChemicals that slowly wear things down — the same way air and water rust metal.. For a glass of water, that's a non-issue. For ten minutes of hot, full-body contact every day, it's the variable worth understanding.

Chlorine: what it does to skin and hair

Free chlorine in U.S. tap water typically runs between 0.2 and 4.0 ppmParts per million — a way to measure a tiny amount of something dissolved in water.. As an oxidizer, it strips the lipidsThe natural oils between your skin cells that act like glue and hold moisture in. that hold the skin barrier together, which raises trans-epidermal water lossHow fast water escapes from your skin into the air. More loss means drier skin. — the rate at which your skin leaks moisture. That's the mechanism behind post-shower tightness, flaking, and itch.

The research is specific. A 2003 study by Seki and colleagues found that free residual chlorine in bathing water reduced the water-holding capacity of the stratum corneumThe outer layer of your skin — like a brick wall that keeps water in and irritants out. in atopic skinSkin that gets dry, itchy, and easily irritated — the kind of skin people with eczema have., with effects observed at concentrations as low as 0.5 mg/L. A 2016 population study in the Journal of Allergy and Clinical Immunology found chlorine exposure was independently associated with eczema risk — even after controlling for water hardness. On hair, chlorine oxidizes the disulfide bondsTiny chemical “springs” that keep hair strong. Chlorine can snap them, so hair turns weak and brittle. in keratin and accelerates color fade.

Chloramine: why your city may have switched

Chloramine is chlorine combined with a small amount of ammonia. Utilities like it for one big reason: it's stable. It holds its disinfecting power far longer as water travels through miles of pipe, and it produces fewer regulated disinfection byproducts than chlorine. About 1 in 5 Americans now receive chloramine-treated water, and roughly a third of U.S. public water systems use it.

That stability is exactly what makes chloramine harder to deal with at home. Free chlorine off-gasses — leave a glass out overnight and much of it is gone. Chloramine doesn't. It won't evaporate if water sits, and boiling isn't a reliable way to remove it. Reducing it takes a filter with enough carbon and enough contact time to do the work. A thin, cheap cartridge that handles chlorine may barely touch chloramine.

Microplastics: the third variable

Disinfectant isn't the only thing coming out of your tap. A landmark Orb Media investigation, with samples analyzed at the University of Minnesota, found that 83% of tap-water samples across five continents contained microscopic plastic fibers — including water from the U.S. EPA's own headquarters. MicroplasticsPlastic pieces so small you can’t see them, now found in a lot of tap water. are a newer and still-developing area of research, but they're increasingly detected at levels worth filtering, which is why a good point-of-use filter targets them alongside chlorine and chloramine.

How to find out what's in your water

You don't have to guess. Every U.S. utility publishes an annual Consumer Confidence ReportA yearly report card your water company must publish showing what’s in your tap water. (also called a water quality report) that lists the disinfectant it uses. Search your city's name plus "water quality report," or check your provider's website. If it says chloramine, prioritize a filter built to handle it — not every filter is.

Look up your city’s water system — EPA database →

One thing the report won't change: chlorine and chloramine are about disinfection, not hardness. If your water is "hard," that's dissolved minerals, a separate issue that a point-of-use filter doesn't address. Be wary of any product that blurs the two.

What reduces them at the point of use

For the water you actually wash with, a point-of-use filter is the practical fix. Filterbaby shower filters are designed to reduce up to 99% of chlorine, chloramine, and microplastics, installed in under five minutes with no plumber. The Pro Series and Diamond Series shower filters are independently certified to NSF/ANSI 177 by IAPMO, and the Filterbaby shower filter is the only shower filter approved by the American Hair Loss Association.

What a shower filter is not is a water softener. It reduces chlorine, chloramine, and microplastics — it does not remove water hardness, and it isn't a whole-house system. If your goal is taking the daily oxidizing exposure off your skin and hair, that's exactly the job it's built for.

Frequently asked questions

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