Chlorine has been used to disinfect public water supplies since 1908 — two years before the first motion picture was released. A powerful antimicrobial, it kills bacteria and parasites that can make us sick.
Chloramine, an alternative disinfectant, was introduced in 1929. Used with or instead of chlorine by water systems across the country, it has benefits that chlorine doesn’t — but it’s tougher for the average water filter to remove.
If you have chloramine in your city water, you’ll want to read this guide. We’ll demystify this little-known chemical and show you once and for all how to remove chloramine from water.
Spoiler: forget the ordinary carbon filter…
What Is Chloramine?
Chloramine is a blend of chlorine gas and ammonia. Used regularly until 1939, water treatment plants turned to chlorine exclusively in the 1940s because of ammonia shortages during World War II.
Today, chloramines are back, mostly as a secondary disinfectant. According to the Environmental Protection Agency (EPA), at least one in five Americans drinks water containing chloramines.
Is It Chloramine or Chloramines?
Chloramines are a group of chemicals, so the word is often pluralized. Monochloramine, however, is the form most often used for water disinfection, so either term is correct.
Why Is Tap Water Treated with Chloramine?
Municipal water supplies are disinfected to prevent waterborne disease. The World Health Organization reports that 40 million deaths annually are directly attributable to dirty water.
Chlorine has unwanted health effects, but it saves lives. Chloramine is as effective but with advantages and disadvantages of its own.
Learn more about what’s in tap water.
Chloramines — The Pros and Cons
If chlorine and chloramine are equally effective, then why do water treatment facilities use both? The simple answer is — chloramine has advantages that chlorine doesn’t:
It’s More Cost-Effective
Chlorine is volatile and evaporates readily. Levels drop quickly after water leaves the treatment plant, so more is required to control bacteria and algae in far-away distribution pipes.
Chloramine is a weaker disinfectant, but it takes significantly longer to evaporate. It continues to kill bacteria long after free chlorine concentrations drop. A little goes a long way.
It Smells and Tastes Better
Ounce for ounce, chloramine smells and tastes like chlorine. But because concentrations in the water supply are typically lower, the flavor and odor are less potent.
It Produces Fewer Disinfection Byproducts
Chlorine produces disinfection byproducts, such as trihalomethane, chlorate and benzene. Known carcinogens, levels of these toxic chemicals are regulated by the EPA.
Chloramines produce similar byproducts, but they’re less volatile and pose a limited health risk. So, using less chlorine and more chloramine helps water treatment facilities meet safety goals.
Do chloramines have disadvantages? They do.
Challenging to Produce
Chlorine and ammonia are difficult to combine without producing potentially toxic gas. It’s a hazardous process, so safety measures at the water treatment plant are critical.
Chloramines are more corrosive than chlorine — something the people of Flint, Michigan discovered in 2014.
When the City of Flint changed water suppliers, it failed to treat aging underground infrastructure with corrosion inhibitors to offset higher acidity levels. Combined with the use of chloramines, it caused lead pipes to deteriorate, resulting in widespread poisoning among local children.
Resistant to Activated Carbon Filters
Activated carbon removes up to 99% of chlorine without breaking a sweat. But because it can’t remove ammonia, it only reduces chloramines by 50% or less.
Frequently Asked Questions About Chloromines
What Are the Health Risks of Chloramines?
Chloramine in the water supply protects you from pathogens. But like chlorine, it has potential health risks.
Both are respiratory irritants that can cause unpleasant symptoms such as:
- Dry skin
- Nasal congestion
- Eye irritation
But while chlorine is linked to bladder cancer, chloramines are more likely to cause digestive disorders and lung issues, including asthma exacerbations and shortness of breath.
Levels in tap water are regulated to minimize adverse health effects, but few studies show how long-term chloramine exposure impacts the human body.
How Much Chloramine Is Too Much?
The EPA limits chloramine concentrations in drinking water to 4.0 mg/L. But there’s a wide gap between the lowest safe minimum of 0.5 mg/L and the maximum. Factors from where your home is located within the water distribution system to how contaminated your water is will impact the concentration in your cup. How much is too much depends on how it affects you personally.
A target of 2.0 – 3.0 mg/L is ideal but not always achievable. Treatment officials focus on the safety of water as it leaves the treatment plant. Once it reaches your home, the rest is up to you.
Should I Filter Chloramines?
At low levels, both chlorine and chloramine are safe. But they make your tap water taste bad and can affect your health in unpredictable ways.
Whether you remove chlorine or chloramine from your tap water is a matter of preference. Some people are more sensitive to these chemicals than others.
But once disinfectants have done their job, why drink them when you can remove them? Even beneficial chemicals in your tap water are risky.
Does Letting Water Sit Remove Chloramine?
Letting water sit on the counter for a few hours is a tried-and-true way to remove chlorine. But it takes days for chloramine to evaporate, making it an impractical though not impossible way to reduce levels.
Does Boiling Water Remove Chloramine?
Boiling water to remove chloramines is almost as ineffective as letting it sit. Because it doesn’t off-gas readily in steam, it takes an hour of boiling to achieve meaningful reductions.
If you want to remove chlorine or chloramine for limited applications, such as home brewing or filling an aquarium, boiling is one solution. But for purifying drinking water, it’s a long wait.
How to Remove Chloramine from Drinking Water
Getting rid of chloramines isn’t as straightforward as removing chlorine, but it’s not complicated once you know the facts.
For most people, installing a filtration system is the best choice, so let’s review the options.
1. Activated Carbon
Granular activated carbon filters struggle to remove chloramines. Yet even a 50% reduction helps tame the chemical taste and reduce the health impact.
An activated carbon filter costs less than a premium cup of coffee, so it’s a good fit for any budget.
2. Catalytic Carbon
Catalytic carbon succeeds where ordinary carbon fails. Made from carbon activated with iron hydroxide, it eliminates 99% of chloramines plus higher percentages of heavy metals, volatile organic chemicals and other contaminants than the average activated carbon filter.
Catalytic carbon filters cost up to 40% more, but the consensus is that it’s worth it for the superior contaminant removal.
Looking for a whole home solution? Have a look at our whole house catalytic carbon filters.
3. Reverse Osmosis
The reverse osmosis process forces water through a semi-permeable membrane that removes all contaminants larger than its pores, from fluoride to dissolved solids. The gold standard for water filtration, it nonetheless has an Achille’s heel — chlorine.
But reverse osmosis units are equipped with carbon filters that remove chlorine before it can damage the membrane. The membrane then removes ammonia, resulting in chlorine- and chloramine-free drinking water. Budget-friendly, reverse osmosis systems start as low as $299.
Distillation is a centuries-old way to disinfect water. Steam from boiling water is captured and condensed into pure drinking water.
The process effectively removes both chlorine and chloramine, but filtration capacity is limited. A home distiller running 24/7 produces only 6-8 gallons per day — enough for a single or couple but not for a family. The good news? They’re portable and cost less than $100.
Can Chemicals Neutralize Chloramines?
Potassium metabisulfite tablets neutralize chlorine and chloramine. Used by home brewers to kill bacteria and wild yeast, adding one tablet to five gallons of water reduces disinfectants to negligible levels.
The tablets are cheap, so it’s an effective option for treating small quantities of water. But over time, it’s less convenient and not as cost-effective as a catalytic carbon filter or a reverse osmosis system.
Should I Test My Tap Water for Chloramines?
Water treatment officials can tell you which disinfectants they use and what the levels are — finding out is as simple as making a phone call. But concentrations vary from home to home, so we recommend testing. It’s important to know what’s in your water.
If you’re considering filtration systems, we recommend comprehensive testing with SimpleLab’s Tap Score. Their Essential City Water test checks for 47 substances, including free and total chlorine — total chlorine minus free chlorine equals the chloramine level.
Or you can purchase test strips that include both parameters. But the more you know about your water before you buy a filter, the better decision you can make. The knowledge is rarely wasted.
Choosing the Right Water Filter to Remove Chloramines
There’s no shortage of options when it comes to water filters that remove chloramines, but which you choose depends on four factors:
The Contaminants in Your Water Supply
If you’re among the lucky souls with nothing harmful in your drinking water except residual chloramine, a basic catalytic carbon filter is all you need.
But if a water test reveals unpleasant surprises, such as high levels of lead or other chemicals, you might need a more comprehensive filtration system, like a reverse osmosis unit.
How Chloramines Affect Your Health
There are two types of filtration systems — whole-house filters that treat water throughout your home and point-of-use filters, like countertop and under-sink systems, that purify small volumes for drinking and cooking.
Since hazardous substances are the most dangerous when ingested, cleaning up your drinking water is a priority. But when it comes to chlorine and chloramine, both can dry out your skin and affect your breathing in the shower. If you have someone in your home with eczema or asthma, a whole-house water filter is ideal.
Household Water Demand
The average family uses 320-400 gallons of water daily. A few are for drinking, the rest are for showering, laundry and cleaning. But not all filters can meet those needs.
A whole-house catalytic carbon filter produces clean water on demand from every tap, so there’s plenty for all applications. But an under-sink reverse osmosis filter can only store 3-5 gallons at a time, and daily capacity is limited to less than 100 gallons from a single faucet.
If you want filtered shower water but need reverse osmosis filtration for your drinking water, whole-house and RO systems can be combined. A more economical solution is to pair an RO filter for your drinking water with shower filters in every bathroom.
Any water filter is better than none. Cheaper than buying bottled water, it doesn’t have to be perfect to be effective.
Whole-house filters cost more than point-of-use systems upfront, but they’re usually a better long-term investment. Still, if you’re shorter on cash than chloramines, do the best you can now and build on your system later. If you have $35, you can afford an NSF-certified catalytic carbon faucet filter today.
Disinfecting water saves an estimated 2 million lives annually, but safety concerns make it a double-edged sword. Until the health impact of chloramine is clear, filter it — don’t drink it.