How to Remove Chloramines from Water

Posted by
Brock Robinson on January 10, 2020

Chloramines are heralded for their ability to keep public drinking water safe, but unfortunately, they have some nasty side effects. From skin and eye irritation to a sharp chemical taste, chloramines can leave you with bloodshot eyes after a shower and ruin the taste of your drinking water. Unfortunately, chloramines are much trickier to remove from water than free chlorine. A standard carbon filter won’t remove chloramines alone. Instead, a more comprehensive water filtration system like reverse osmosis or a catalytic carbon filter is required. 

What are chloramines? 

Chloramines are a water disinfection agent widely used by municipalities to sterilize drinking water. Chloramines are formed when both chlorine and ammonia are added to the water supply. City water distributors use surface waters like lakes and large rivers, reservoirs, and groundwater supplies like underground aquifers. This water is often teeming with bacteria, protozoa, and microorganisms. To ensure those who rely on city water are kept safe from waterborne diseases, the municipal water treatment centers must first disinfect the water. 

Traditionally, city water suppliers have relied solely on chlorine for water disinfection. When chlorine is added to water, it initiates a process called oxidation. The chlorine forms a weak acid (called hypochlorous acid) that has a neutral electrical charge. This acid then penetrates the cell walls of bacteria and eliminates the bacteria. Chlorine was first used as a disinfectant in the United States in 1908 in Jersey City. When public health officials realized that waterborne illnesses like cholera, dysentery, and typhoid were virtually wiped out, they realized the necessity of disinfecting public water supplies. In fact, Life magazine cited the chlorination of water as one of the most significant health advancements of the century. 

However, after the water is disinfected, both chlorine and chloramines have a string of undesirable side effects. They are notorious for aggravating skin conditions, ruining the taste of drinking water, and can even degrade rubbers and corrode metal pipes. So, while they serve an integral purpose in keeping water safe and clean, there’s no reason to leave them in the water once they’ve served their purpose. 

Why are chloramines used in water?

Chloramines are used to disinfect water because of their remarkably long-lasting disinfection properties. Celebrated for their strength as a “secondary disinfectant”, chloramines remain in the water much longer than chlorine. Chloramines are a very stable compound, and won’t readily dissipate or lose potency. Though a weaker disinfectant than chlorine, they retain their disinfection characteristics much longer than chlorine. This means even if you are the home all the way at the outskirts of the city and at the end of the water main, your water will still come out of your tap disinfected and full of chloramine. Now, over 20% of Americans on city water drink water that has been treated with chloramines instead of chlorine.  

Chlorine does have several downsides. Chlorine is a very volatile compound and is eager to dissipate from the water supply. EPA standards require that there is a residual 0.5ppm of the disinfection agent in the water. Since chloramines are so stable, this is easily achieved. Chlorine, however, is far more likely to gas off and leave the water before that house at the end of the municipal supplier. Additionally, when chlorine is added to a water source with organic matter (like a lake or river) it creates “disinfection byproducts” (or “DBPs”.) One of these, trihalomethane (or THM) is a volatile organic compound with several significant health implications. Prolonged consumption of THMs is linked to reproductive complications and cancer. While municipal treatment plants work diligently to ensure that the DBP levels remain low in their water, chloramines offer a safer alternative in this regard. They do not create any byproducts when combined with organic matter. 

water treatment plant with chloramines

Why should I remove chloramines from my water? 

Unfortunately, chloramines come with many disadvantages. Though they help keep the public safe from ingesting illness-causing bacteria and protozoa, they are notorious irritants with corrosive properties. 

1. Skin and eye irritation

Chloramines’ biggest offense is their aggravation of skin conditions and irritation of the eyes and sinuses. Some people with skin sensitivity find themselves breaking out in rashes after bathing or showering in water with chloramines. If you have a pre-existing skin condition, like eczema, or acne, chloramines can severely exacerbate these problems. They’re known to cause hive-like outbreaks and cause your skin to dry out and become scaly and flaky. While ideally this could be solved by installing a shower filter, unfortunately, almost all shower filters are incapable of removing chloramines because of their design. 

Chloramines also cause eye irritation. Some people emerge from the shower with stinging, bloodshot eyes like you spent an hour in the pool after exposure to chloramines. It can upset your nasal passages, your mucous membranes, and your sinuses as well. This is because in enclosed spaces (like a shower stall) you are inhaling the chloramines as vapor as you shower. For people with sensitivity to chloramines, this can trigger extreme discomfort in their sinuses. 

Learn more about how shower filters work.

2. Taste and odor

Chloramines actually have less of a chemical aftertaste than the more commonly used chlorine. However, they still leave water with an unfortunate metallic or chemical tang. Chloramines also impart a particularly harsh smell on water. That infamous “pool water smell” you know so well? That’s actually chloramines, not chlorine. The taste and odor of chlorine and chloramines is the most common residential water quality issue. Many turn to refrigerator water filters or water filter pitchers to address these taste and odor concerns. However, chloramines aren’t removed by the majority of standard water filtration systems. Since they are such a stable compound, they require elevated measures to be reduced in your water. 

3. Deteriorates rubber

Exposure to chloramines will degrade rubber over time. O-rings, gaskets, and seals will all be broken down by the chloramines. The O-rings sealing your quick-connect fittings together will be eaten away by chloramines, causing them to spring leaks. If you have water filtration systems with O-ring seals, like UV purification systems or ice filtration, these too will be broken down by chloramines. Your sinks, dishwashers, laundry machines, faucets, toilets, and fixtures all have rubber components that will slowly be destroyed by the chloramine. The effects of this can be inconvenient, not to mention costly. It’s frustrating to replace small rubber parts throughout your home plumbing. But it can be disastrous if one of your appliances springs a leak that results in your dishwasher or washing machine pouring water out all over your floorboards. 

Read more on how to fix leaking quick-connect fittings

4. Corrosion

Not only are chloramines destructive to rubber, its been recently revealed they have corrosive properties that can damage metal pipes. When chloramines are added to public water supplies, sometimes the water undergoes a transformation of chemical properties. This, in conjunction with lowered pH and alkalinity, can result in corroded pipes. Another process, called nitrification, occurs when corrosion control is not optimized and the ammonia in the water converts into nitrates.  If left unchecked, copper plumbing in homes can spring pinhole leaks. Often these can be hidden and the homeowner may be unaware of them until substantial damage has already transpired. 

Even worse, this corrosion can introduce lead into the water if proper corrosion control is not in place. This exact even happened in Washington, D.C. When they switched from chlorine to chloramines in their water supply, they did not properly adjust the corrosion control of their water. As a result, many D.C. residents were accidentally exposed to lead. Lead is extremely toxic and ingesting it presents a host of health problems, stunts development in children, and harms pregnant women and unborn children

5. Toxic to fish and plants 

If you own an aquarium, be very careful you do not replenish the fish tank with water containing chloramines. Fish have very fragile internal organs and are extremely sensitive to chemicals like chloramines. Hydroponics farmers or hobbyists should be careful to eliminate chloramines from their water, as exposure to the chemical can upset the delicate balance of the nutrient solution and result in the death of their crops. Chloramines interfere with a host of other water-based industries and hobbies. From brewing beer to brewing coffee, chloramines will offset the flavor profile of any beverage it is introduced to. Additionally, water with chloramines should never be used in a medical or laboratory setting. Be careful to make sure any dialysis machine or CPAP machine is not utilizing water with chloramines, as it could result in adverse health effects. 

Explore how to achieve perfect water in your aquarium. | Learn how water filtration benefits hydroponics

Are chloramines safe to drink?

According to the EPA’s water quality regulations, it is safe to drink water with up to 4mg/L of chloramines. In general, chloramines are not believed to be a health hazard. Studies have demonstrated that drinking water with 4 mg/L (or 4ppm) of chloramines is not linked to any illness or longterm health effects. Since municipal water suppliers are held to strict guidelines when it comes to the water they distribute, it is very unlikely that you would be exposed to water with greater than 4 mg/L of chloramine. 

The sole exception to this is hemodialysis patients. Chloramines are able to enter the bloodstream of hemodialysis patients through the dialysis membrane. Once in the bloodstream, chloramines alter hemoglobin, resulting in a potentially life-threatening condition called hemolytic anemia. If you are on dialysis, you should seek to avoid the use of water with chloramines. 

water treatment facility

How do you remove chloramines from water? 

Chloramines are best removed from water by catalytic carbon filtration. Catalytic carbon, activated carbon with an enhanced capacity for contaminant removal, is one of the few filtration media that can successfully reduce chloramines from drinking water. Carbon filters, the industry standard for chlorine removal, is an ineffective chloramine filter. The stability of chloramines, the quality which makes them such a powerful disinfectant, also makes them so difficult to remove. The amount of contact time required for activated carbon to cause any significant reduction in chloramines is so long it makes it entirely impractical. It would reduce flow rates drastically and no house could feasibly use a carbon filter to remove chloramines and maintain usable water pressure and flow. 

There are also under-sink options available that can reduce chloramines from your water supply, like reverse osmosis and ultrafiltration. However, these are less commonly employed. Chloramines are best removed by whole house water filters. Since one of their biggest offenses is their aggravation of skin conditions and irritation of the eyes and sinuses, most people seeking to eliminate chloramines will opt to remove it from every fixture in their house, not just from their drinking water. 

What is catalytic carbon? 

Catalytic carbon is activated carbon that has gone through additional treatment to enhance carbon’s capacity to facilitate chemical changes. Chemical reactions require a catalyst. The surface area of catalytic carbon has been structurally enhanced and altered to provide a space for chemical reactions to occur. Catalytic carbon still possesses the remarkable adsorption properties of activated carbon, but it has been supercharged to target other contaminants as well. This includes chloramines. When chloramines come in contact with the catalytic carbon, a chemical reaction catalyzes a separation of the ammonia and the chlorine and converts them into harmless compounds in the water. 

Catalytic carbon is most often found in whole-house, backwashing tank filters. Installed at the point-of-entry, all of the water flowing into the home passes through the catalytic carbon. Chloramines, (as well as VOCs and hydrogen sulfide) are all greatly reduced by the filtration system. The water from your tap is free from the chemical taste and odor, and your baths and showers are free from stinging, burning, and itching sensations. 

Why doesn’t activated carbon remove chloramines? 

Chlorine, on contact with the carbon, chemically alters into the harmless compound called chloride. Carbon filters have expansive surface areas with these exchange sites and are remarkable at removing standard chlorine from water supplies. Chloramines, however, have unique stability as a compound. Upon contact with activated carbon, they are not catalyzed with the same efficiency and speed. In order for activated carbon to remove chloramines, very extensive contact time is required to successfully break the ammonia and chlorine apart. This makes them a poor choice for chloramine reduction, as you could not run a shower or fill a bath with such reduced flow rates. Since skin sensitivity is one of the primary reasons people eliminate chloramines, a filtration system capable of sustaining at least a moderate flow rate is crucial for success.

Read more about how activated carbon works.

Does reverse osmosis remove chloramines? 

The reverse osmosis membrane alone technically does not remove chloramines. However, reverse osmosis systems are equipped with multiple pre-filters. The carbon in these pre-filters is able to remove chloramines, because of how slowly the reverse osmosis process works. Reverse osmosis purifies water one drop at a time, passing the water through a semi-permeable membrane capable of rejecting a host of contaminants like arsenic, salts, and boron. The rejected, contaminant-ridden water (called brine) is sent to the drain. The purified water, called permeate, is collected in a storage tank. When you desire access to cold, highly pure water, it is pulled from the storage tank and delivered to your tap.

Reverse osmosis has a very slow rate of production, meaning that the carbon filters in front of the RO membrane have ample contact time with the water. As discussed above, the stability of the chloramine compound is difficult to disrupt. Activated carbon can remove chloramines, but the flow rate must be slow. The more carbon filters before and after the RO membrane, the greater the reduction of chloramines in the water. 

Ultrafiltration systems, like the TL3, are also adept at chloramine reduction. Ultrafiltration systems combine sediment and carbon pre-filters with a hollow fiber membrane capable of reducing contaminants as fine as 0.025 microns. Since the water is passed through carbon blocks at a reduced flow rate (around 1 GPM) and a membrane with minute pores, these under-sink systems are rated to reduce up to 95% of chloramines in your water. If you are seeking to eliminate chloramines exclusively from the water you drink and cook with, both reverse osmosis and ultrafiltration systems are excellent filtration options.

Discover how reverse osmosis works. | Learn more about how ultrafiltration works. | Explore our 5 favorite under-sink systems.

Comments 1-1 of 1
Leave a comment