If you think there is chlorine in your water, there is a very high chance that you’re right. To meet the EPA water safety guidelines, nearly all communities in the United States use chlorine or chloramine as a disinfectant to kill contaminants in their water systems, but there are also ways to know if you have chlorine in your water for certain.
To know if there is chlorine or chloramine in your water you can check the water aesthetics or by using pool test kits, color disc test kits, chlorine test strips, a digital colorimeter, or sending a sample for certified laboratory testing.
This article will explain what exactly chlorine and chloramine are, why they are added to your water supply, their benefits, and the possible harm these chemicals can cause. We will take a detailed look at the various methods you can use to detect the presence of chlorine or chloramine in your water and take you through ways to remove these chemicals from your water.
How to Know If You Have Chlorine (Chloramine) in your Water
When chlorine is added to water, it reacts with the organic and inorganic compounds and metals that may be present in the water. These substances ‘soak up’ the chlorine and make it unavailable for disinfection. This is known as the chlorine demand of water.
When the chlorine demand has been met, the chlorine left in the water is total chlorine. Total chlorine is made up of:
- Combined chlorine which is chlorine that has reacted with the organic and inorganic substances in water and is unavailable for disinfection
- Free chlorine which is the leftover chlorine that is available for disinfection.
There are six common methods that you can use to check if there is chlorine in your tap water. These methods detect either the presence of total chlorine or free chlorine alone.
1. Water Aesthetics
Water aesthetics include characteristics of the water such as color, taste, smell, temperature, etc. One of the quickest and most accessible ways to detect the presence of chlorine or chloramine in water is through its taste and smell.
Chlorine has a distinct smell that may be pungent and irritating depending on its concentration in the water. It smells like bleach and like most swimming pools. So, if the smell and taste of your water remind you of a swimming pool, there is probably chlorine in it.
You start to smell chlorine in your water when it is present in a concentration of about 1 part per million (or 1 gram per liter) which is still below the limit considered safe by the CDC and EPA.
Pros
- It’s a cost-effective method
- It’s quick
Cons
- High chance of inaccuracy
- Not very sensitive. Lower levels of chlorine can easily be missed
- It cannot quantify the amount of chlorine present
2. Pool Test Kits
A typical pool test kit contains a liquid test solution known as orthotolidine (OTO). OTO is a chemical reagent that causes water to turn yellow when chlorine is present. Pool test kits typically contain OTO in small dropper bottles and a color chart for comparison.
To use a pool test kit, fill a tube with tap water and add a few drops of OTO according to what is indicated in the instruction manual. If there is chlorine in your tap water, there will be a color change of the water in the tube to yellow.
If there is a color change, compare it to the color chart in the test kit to get an idea of the amount of chlorine present in your tap water.
OTO is the chemical reagent commonly used to test for the level of chlorine in pools. That is why this is popularly referred to as a pool test kit. However, this test can also be used to check if there is chlorine in your tap water and to give you an idea of how much chlorine may be present.
This technique measures total chlorine, not just free chlorine.
Pros
- It’s easy to use
- Cost is low
Cons
- The OTO solution can degrade, making it inaccurate over time
- The quantitative results from color chart comparison are not always accurate or reliable.
3. Color Disc Test Kits
Color disc test kits use a chemical reagent known as N,N diethyl-p-phenylene diamine, or DPD, in powder or tablet form. When dissolved in a sample of water, DPD turns the water pink if chlorine is present.
The intensity of the color formed depends on the amount of chlorine in the water. To estimate how much chlorine is present in your tap water, fetch the volume of water indicated in the instructions manual of the kit, and add the DPD tablet or powder. When the color changes, visually match it to the color wheel in the test kit.
Color disc test kits can measure either total chlorine or free chlorine alone.
Pros
- Relatively high accuracy if used properly
- Cost-effective
- Quick, especially when powdered DPD is used
Cons
- High chance of user error
4. Chlorine Test Strips
These test strips are a common and convenient method of checking if there is chlorine in your tap water.
A test strip package will typically come with test strips and a color chart.
To use this method, take a sample of water in a container and dip a test strip in for a few seconds, depending on the instructions in the package. Some test strips may require you to hold the strip under running water, so be sure to go through the manufacturer’s instructions.
When the strip has been removed from the water, check to see if there is a color change. Compare it to the color chart to estimate the chlorine level in your water.
Chlorine test strips can either test for free chlorine alone or both free and total chlorine (like this one on Amazon).
Pros
- Relatively cheap
- Simple to use and give quick results
- Easily available on the market
Cons
- Relatively low level of accuracy
- Prone to spoilage if exposed to moisture or intense or prolonged sunlight.
- Relatively short lifespan, usually lasting only about a year.
5. Digital Colorimeter
This is one of the most accurate methods of testing for chlorine in your tap water.
The digital colorimeter is good to have on hand if you want to know the precise amount of chlorine present in your tap water.
This method requires the use of DPD powder or tablets as well. To use it, add DPD into a vial of tap water. When the water turns pink, insert the vial into the digital colorimeter and set it to begin reading.
The digital colorimeter measures the intensity of the color produced by the reaction between DPD and chlorine and uses it to calculate, with high accuracy, the chlorine concentration in the sample.
Pros
- High accuracy
- Fast
- With the appropriate reagents, it can be used to check for other impurities in the water as well
Cons
- Relatively expensive
- Requires calibration and standardization Relatively technical
- Relatively technical
6. Certified Laboratory Testing
This is the go-to method if the test kits and other methods don’t cut it for you.
Certified laboratory testing involves sending off a sample of your tap water to a certified lab. They provide quantitive results for the total chlorine content in your water sample.
We recommend the Tap Score Water Test package which contains all the instructions and materials needed to take a sample of your tap water and send it in for analysis.
Turn around time is about 5 days, after which the lab will send you a detailed report of the chloride content of your water sample as well as some tips on what next steps to take.
This method may not be as quick as the others, but it is worth the wait. When it comes to your drinking water, it doesn’t hurt to go the extra mile.
Pros
- Very accurate
- Results are detailed
- Comes with personalized professional recommendations
Cons
- Results are not immediate
- Relatively expensive
What is Chlorine and Why is it Added to Water?
Chlorine is one of the most manufactured chemicals in the United States. It has one of the most widespread applications across the entire world.
Chlorine is a chemical element that is widely used all over the world as a disinfectant because of its strong anti-bacterial properties. In its pure form, it exists as a toxic, dense, greenish-yellow gas at room temperature. When added to water in certain quantities, chlorine destroys disease-causing microbes, making the water safe to drink.
The process of adding chlorine into water as treatment is known as chlorination. Chlorination is over a century old and is the most common method of water disinfection all over the world. It is used in water for pools, manufacturing industries, and homes.
Since the widespread adoption of chlorination, there has been a significant drop in the risk of people contracting waterborne diseases such as cholera, salmonella, dysentery, etc. Considering that these diseases used to affect thousands of Americans every year, chlorination has been referred to as one of the greatest healthcare achievements of the 20th century.
Chlorine also removes other contaminants, such as iron and manganese, from water. It does this through a process called oxidation, which ultimately causes these metals to settle out of the water. When in a proper amount, chlorine helps improve some aesthetic qualities of water as well by neutralizing foul tastes and smells.
Chlorination is considered safe for disinfecting drinking water as long as the chlorine present in the water is below a certain level which the National Primary Drinking Regulations has placed at 4 parts per million (or 4 grams per liter).
However, recent research is discovering that chlorine may not be as safe as science previously proclaimed it to be. This is because free chlorine in water reacts with organic compounds in water to form toxic disinfection by-products (‘DBPs’). The most toxic DBPs formed by chlorine are trihalomethanes (or THMs).
Chloramines are a solution to the issue of DBPs produced during chlorination. Chloramine is a chemical produced when chlorine reacts with ammonia. Chloramines are more stable than chlorine and produce significantly fewer disinfectant by-products than chlorine.
Chloramine lasts longer in water and so is a better option for secondary disinfection which is done to protect water against contaminants that may enter as it moves through the pipes.
To meet up with EPA regulations concerning DBPs, more and more communities are switching from chlorine to chloramine in their water supply. According to the EPA, more than one in five Americans drink chloramine-treated water.
Chloramination is when chloramine is used as a disinfectant in the treatment of water.
Chlorination and chloramination are preferred means of water disinfection by water suppliers because chlorine is cheap, easily available, easy to use, and very effective, but it can leave your water tasting like chemicals.
What happens if you drink water with too much chlorine?
While chlorine is a literal life-saver when used as a disinfectant in water, it is still a chemical. In recent years, health concerns have been rising concerning the use of chlorine in city water.
THMs are the toxic substances formed from chlorine reacting with organic matter and have been linked to an increased risk of developing bladder cancer as well as rectal and colon cancer.
When pregnant women are exposed to THMs, it increases their risk of experiencing stillbirths and of giving birth to children with congenital anomalies such as cleft palates, holes in the heart, and poor brain development.
Another drawback of chlorine is ironically linked to its biggest strength – its anti-bacterial properties. When you drink chlorinated water, the chlorine unfortunately also acts on the beneficial bacteria present in the gut. A healthy, thriving community of gut bacteria is essential for maintaining good health.
When gut bacteria are affected by chlorine, it increases the risk of illnesses such as irritable bowel syndrome, especially among children
Chlorine also has negative effects on your skin and hair.
Normally, your body produces a protective layer of proteins and oil that covers your skin and hair strands. Chlorine depletes this protective layer, leaving your skin and hair vulnerable to the harsh environment. This can result in dryness and irritation of your skin. Your skin may start to become flaky, and your hair dry and frizzy.
It is important to note that these effects are not limited to the chlorine you drink in water alone. When chlorine is inhaled, these harmful effects are even more likely to occur because inhaled chlorine is likely to be absorbed into your bloodstream more quickly.
This applies to chloramine as well which has more aggressive effects when inhaled. Chloramine fumes can lead to respiratory problems and aggravate any existing respiratory issues you may have. It causes sneezing, congestion, coughing, and shortness of breath, and is associated with symptoms of asthma.
How does chlorine (chloramine) affect dialysis patients?
Dialysis patients can drink chlorine or chloramine-treated water, but these disinfectants are removed from the water used for dialysis. Chlorine (and chloramine) can contaminate the dialysis fluid and enter patient’s bloodstream. Blood transfusions are required to treat the hemolytic anemia that is caused by the contamination.
Before using water for dialysis, dialysis centers routinely treat it to remove all disinfectants, including chlorine and chloramine.
Home dialysis patients should consult their physicians and the manufacturers of their dialysis machines for proper guidance on how to treat their water before it gets used for dialysis.
Will chlorine or chloramine affect my pets or plants?
Chlorinated or chloraminated water is safe for plants and household pets such as mammals and birds. However, chlorine and chloramine are toxic to reptiles, amphibians, fish, and other aquatic animals because these absorb water directly into their bloodstream.
But with humans and other non-aquatic animals, these chemicals are neutralized by the digestive system.
Pet stores and aquarium supply stores sell products that can remove these disinfectants from water.
Chlorine levels in tap water are usually safe for watering plants. However, filtered water is much better because chlorine can kill some beneficial bacteria in the soil.
Can well water contain chlorine?
Chlorine occurs in nature in the form of chloride salts such as sodium chloride (NaCl) or calcium chloride.
Chlorine does not occur in its free state in nature. So, unless you put it in, your well-water is unlikely to contain chlorine.
