What to do about chlorine allergy

Chlorine rash can happen whenever you've spent time in chlorinated water, love a pool or boiling tub. It appears a short time after getting into the pool, or within a few hours after swimming.

Itching is generally the first sign something is amiss. The skin can feel dry and scaly and may burn. Red bumps appear across any areas that were exposed to chlorine, but they don't always appear evenly across the skin. The bumps often crop up in patches. Your skin may also be red, swollen, or tender. In more severe cases, hives develop.

Chlorine rash is not contagious.

It can't spread from one person to another. And while you may own clusters of itchy bumps across your body, chlorine rash doesn't spread after the first day or so (provided you're staying out of the pool at this point).

Other Rashes You Can Get From Swimming

There are other rashes you can get from swimming beside chlorine rash. Although numerous of these are colloquially called swimmer's rash, they are diverse types of rashes with diverse causes.

  1. Seabather's eruption is caused by larvae that live in the ocean. You won't get this from swimming in pools.
  2. Hot tub folliculitis (AKA boiling tub rash) also causes an itchy rash and pus-filled bumps.

    Unlike chlorine rash, though, the culprit is bacteria love Pseudomonas. Boiling tub folliculitis tends to be worse in areas that were covered by your swimsuit. Boiling tub rash generally goes away without treatment after a few days.

  3. Swimmer's itch, more precisely cercarial dermatitis, is caused by tiny parasites. You're not likely to get this after swimming in a pool that's properly maintained, but rather after swimming in rivers, lakes, and ponds.
  4. Bikini bottom causes red, inflamed, pimple-like bumps on areas covered by your swimsuit.

    It happens after sitting around in wet bathing suits for endless periods of time, allowing bacteria to infect the skin's follicles. It should be treated with antibiotics.

Wondering Why You Own an Itchy Rash After Swimming in the Ocean?

Who Gets Chlorine Rash

People who spend lots of time in the pool are prime candidates for developing chlorine rash. It's more likely to develop with repeated exposure, so you can get chlorine rash even if you've swum previously without issue.

Swimmers aren't the only people who own to watch out for chlorine rash. If you simply take care of a pool or boiling tub, you can develop it too.

People who are responsible for putting chlorine into the pool may develop a rash if some of the chlorine gets onto their skin.

Some people are more sensitive to chlorine than others, so you can develop a rash while others who swam in the same pool don't. If you own eczema or psoriasis you may be more susceptible to developing chlorine rash, because your skin is already sensitized.


The ancient adage an ounce of prevention is worth a pound of cure is particularly fitting when it comes to chlorine rash.

Although you might not be capable to completely prevent a rash—especially if you are extremely sensitive to chlorine or spend a lot of time in the water—these tips can assist limit your chance of developing a rash.

  1. Don't sit around in a wetsuit or trunks. Shower and change ASAP.
  2. Use post-swim chlorine removal spray if it's not possible to shower immediately after swimming. Glance for one that contains vitamin C, as this helps neutralize chlorine.
  3. Shower immediately after coming out of the water, if your pool has shower facilities available. Just a simple rinse isn't enough to remove chlorine, though, so you should also follow up with a shower and soap as soon as you can, preferably with a tender, non-drying soap or body wash. If you prefer, or you're especially prone to chlorine rash, you may desire to attempt a post-swim chlorine removal body wash.
  4. After showering, slather your skin with a tender, fragrance-free lotion or cream to assist moisturize and reduce dryness caused by chlorine.
  5. Some recommend applying a moisturizer, a extremely thin layer of petroleum jelly, or a pre-swim lotion to the skin 15 minutes or so prior to getting in the water.

    The thought is that this creates an additional barrier between your skin and the chlorinated water. Although this theory hasn't been proven, you may desire to attempt it to see if it works for you.

  6. Rinse off prior to getting into the pool or boiling tub. This helps rinse away sweat and oils on the skin that can react with chlorine, causing an irritating reaction.
  7. Monitor the chlorine levels in your pool or spa. Attempt to avoid getting them too high, and use test strips to measure chlorine levels before taking a dip. If you're swimming in a public pool, you obviously don't own control over how much chlorine there is or when it's added.

    But you can enquire when chlorine is typically added and avoid swimming during those days since the chlorine levels will be higher, and stay out of the pool if you notice a extremely strong chlorine smell, as this means there are high levels of skin-irritating chloramines.

Hot to Treat Chlorine Allergy Attack

Whenever you suspect a serious allergic reaction glance for urgent emergency care. Skin sensitivity is normally treated by washing the affected area with clean water. To attempt to remove any hints of the relax of the irritant, i.e., cleaning item or pool water.

Chlorine allergy can be treated at home with over-the-counter drugs. Most rashes will clear up following a few days.

Over-the-counter hydrocortisone creams decrease the itching, redness, and swelling.

You can get these at your nearby drugstore or local pharmacy. They’re sold under numerous brand names love Cortaid, Cortisone 10, or just conventional hydrocortisone. OTC hydrocortisone creams can be used two to four times each day. Apply a slight layer to the rash, and tenderly rub into the skin until it’s completely absorbed.

Topical Benadryl (diphenhydramine) creams are another over-the-counter choice.

They assist ease itching and irritation from the chlorine rash and can be extremely calming. Apply them up to four times each day to the whole affected area.

Emollient lotions and creams assist moisturize skin dried out by chlorine. You can use these in the middle of use of sedated creams if you need them. Pick a cream that is odorless and hypo-allergenic. This is to refrain from irritating your rash.

When you get chlorine allergy, it can turn out to be progressively irritated the more you go into the pool.

Ponder about taking a break from swimming or boiling tub dipping for some time to enable your skin to recover. If you aren’t getting comfort with over-the-counter medicines, your specialist can prescribe more grounded prescriptions. To assist clear up your rash.

Similarly, you should see your doctor about your allergy if:

  1. Any serious allergic reaction permits emergency treatment.
  2. You own extreme hives or hives that won’t vanish with treatment.
  3. You aren’t certain if your allergy was brought about by chlorine.
  4. Your rash isn’t improving with home treatment.
  5. Your rash is spreading, deteriorating, or appears to be extreme.

A Expression From Verywell

The only foolproof way to stop chlorine rash is to stay out of the pool.

Obviously, that isn't always the best option. If you love swimming or are a competitive swimmer, you'll scoff at the notion to stay out of the pool.

If you already own a chlorine rash, it can become more irritated the more you go into the pool. Consider taking a break from swimming or boiling tub soaking for a while to permit your skin to heal. If you aren't getting relief with over-the-counter treatments, your doctor can prescribe stronger medications to assist clear up your rash.

You can’t be allergic to chlorine, but you can be sensitive or own a reaction.

If you are sensitive, should you stop swimming? No, instead you should discover and treat the cause of your sensitivity and discover relief.

What you ponder is a chlorine allergy might actually be underlying asthma, exercise-induced bronchoconstriction (EIB) or bronchospasm. Your runny nose might be due to other underlying allergy problems.

Chlorine reactions may include itchy, red skin or hives (itchy bumps). This is not an allergy but is actually «irritant dermatitis» (like a chemical burn), caused by hypersensitivity to this natural irritant.

Chlorine is also drying to the skin and can irritate existing dermatitis.

Chlorine may indirectly contribute to allergies by irritating and sensitizing the respiratory tract. Studies own suggested that frequent swimming in chlorinated pools and exposure to cleaning products containing chlorine may increase the risk of developing asthma and other respiratory allergies, both in adolescents and in adults.

Those who own asthma, when they go to a chlorinated pool, if they take a deep inhalation, they will discover that their lungs will actually burn a little bit. In fact, chlorine when it’s in full concentration will burn a normal skin.

But when you discover it in chlorine pools, it’s at a concentration that kills the bacteria, but yet it’s not supposed to be an irritant to the general population.

Allergist Leonard Bielory, MD

This is most detectable in people with long-term exposure, including lifeguards, professional cleaners, and swimmers with more than 1,000 hours of exposure. Numerous Olympic swimmers own suffered from chlorine sensitivity, found relief and gone onto win numerous medals, love six-time U.

S. Olympic gold medalist Amy Van Dyken and five-time Australian gold medalist Ian Thorpe.

It may not impact people with less frequent exposure in fact, some studies own shown household use of chlorine bleach can actually reduce the onset of allergies to household allergens such as dust mites, possibly by inactivating allergens.

Chlorine sensitivity can happen when swimming pools increase the quantity of chlorine, for example, in response to health scares such as «Swine Flu» or E.

coli. Finding facilities with lower chlorine concentrations may resolve your sensitivity.

Chlorine is one of the most commonly used disinfectants for water disinfection. Chlorine can be applied for the deactivation of most microorganisms and it is relatively cheap.

When was chlorine discovered?
Chlorine gas was presumably discovered in the thirteenth century. Chlorine (Cl2) was first prepared in pure form by the Swedish chemist Carl Wilhelm Scheele in 1774.

Scheele heated brown rock (manganese dioxide; MnO2) with hydrochloric acid (HCl). When these substances are heated the bonds are broken, causing manganese chloride (MnCl2), water (H2O) and chlorine gas (Cl2) to form.

Reaction mechanism:
MnO2 + 4HCl -> MnCl2 + Cl2 + 2H2O

Figure 1: Carl Wilhelm Scheele discovered chlorine in 1774

Scheele discovered that chlorine gas was water-soluble and that it could be used to bleach paper, vegetables and flowers.

It also reacted with metals and metal oxides. In 1810 sir Humphry Davy, an English chemist who tested fundamental reations of chlorine gas, discovered that the gas Scheele found must be an element, given that the gas was inseperable. He named the gas ‘chlorine’ (Cl), after the Greek expression ‘chloros’, which means yellow-greenish and refers to the color of chlorine gas (White, 1999.

Watt, 2002)

Where can chlorine be found?

Chlorine can be found on numerous diverse locations every over the world. Chlorine is always found in compounds, because it is a extremely reactive element. Chlorine can generally be found bond to sodium (Na), or in kitchen salt (sodium chloride; NaCl). Most chlorine can be found dissolved in seas and salty lakes. Large quantities of chlorine can be found in the ground as rock salts or halite.

The properties of chlorine

Chlorine (Cl2) is one of the most reactive elements; it easily binds to other elements.

In the periodic chart chlorine can be found among the halogens. Other halogens are fluorine (F), bromine (Br), iodene (I) and astatine (At). Every halogens react with other elements in the same way and can form a large quantity of substances. Halogens often react with metals to form soluble salts.

Chlorine atoms contain 17 negative electrons (negatively charged particles). These move around the heavy core of the atom in three shells. Within the inner shell there are two electrons, within the middle shell there are eight and within the outer shell there are seven.

In the outer shell there is space left for another electron. This causes free, charged atoms, called ions, to form. It can also cause an additional eletron to form (a covalent bond; a chlorine bond), causing the outer shell to complete.

Figure 2: chlorine atoms contain 17 electrons

Chlorine can form extremely stable substances, such as kitchen salt (NaCl). Chlorine can also form extremely reactive products, such as hydrogen chloride (HCl). When hydrogen chloride dissolves in water it becomes hydrochloric acid. The hydrogen atom gives off one electron to the chlorine atom, causing hydrogen and chlorine ions to form.

These ions react with any helpful of substance they come in contact with, even metals that are corrosion resistant under normal circumstances. Concentrated hydrochloric acid can even corrode stainless steel. This is why it is stored either in glass or in plastic.

How is chlorine transported?

Chlorine is a extremely reactive and corrosive gas. When it is transported, stored or used, safety precautions must be taken. In Holland for example, chlorine is transported in separate chlorine trains.

How can chlorine be stored?

Watery chlorine should be protected from sunlight. Chlorine is broken below under the influence of sunlight.

UV radiation in sunlight provides energy which aids the break-down of underchloric acid (HOCl) molecules. First, the water molecule (H2O) is broken below, causing electrons to be released which reduce the chlorine atom of underchloric acid to chloride (Cl). During this reaction an oxygen atom is released, which will be converted into an oxygen molecule:
2HOCl -> 2H+ + 2Cl + O2

How is chlorine produced?

Chlorine is produced from chlorine bonds by means of electrolytic or chemical oxidation.

This is often attained by electrolysis of seawater or rock salt. The salts are dissolved in water, forming brine. Brine can conduct a powerful direct current in an electolytic cell. Because of this current chlorine ions (which originate from salt dissolving in water) are transformed to chlorine atoms. Salt and water are divided up in sodium hydroxide (NaOH) and hydrogen gas (H2) on the cathode and chlorine gas on the anode.

These cathode and anode products should be separated, because hydrogen gas reacts with chlorine gas extremely agressively.

Which methods can be used to produce chlorine?

To produce chlorine, three diverse electrolysis methods are used.

1. The diaphragm cell-method, which prevents products to stir or react by means of a diaphragm. The electrolysis barrel contains a positive pole, made of titanium and a negative pole, made of steel. The electrodes are separated by a so-called diaphragm, which is a wall that only lets fluids flow through, causing gasses that form during a reaction to be separated.

The application of the countercurrent principle prevents hydroxide ions from reaching the positive pole. However, chlorine ions can pass through the diaphragm, causing the sodium hydroxide to become slightly polluted with chlorine. This causes the following reactions to take place:
+ pole : 2Cl -> Cl2 + 2e
— pole : 2 H2O + 2 e -> 2OH + H2

2. The mercury cell-methode uses one mercury electrode, causing the reaction products to be purer than those of the diaphragm cell-methode.

With this method an electrolysis barrel is used which contains a positive titanium pole and a negative flowing mercury pole. On the negative pole a reaction with sodium (Na+) takes put, causing sodium amalgams to be formed. When the amalgams flow through a second reaction barrel, sodium reacts with water to sodium hydroxide and hydrogen. This causes the hydrogen gas to remain separated from the chlorine gas, which is formed on the positive pole.
Within the electrolysis barrel the following reactions take place:
+ pole : 2 Cl -> Cl2 + 2e
— pole : Na+ + e -> Na
second reaction barrel: 2Na + 2H2O -> 2 Na+ + 2OH + H2


The membrane-method resembles the diaphragm method. The only difference is that the membrane only allows positive ions to pass, causing a relatively pure form of sodium hydroxide to form.

During the mercury electrolysis process a solution containing 50 mass-% of sodium hydroxide is formed. However, during the membrane and diaphragm processes the solution must be evaporated using steam.

Sixty percent of the European chlorine production takes put by means of mercury electrolysis, whereass 20% takes put in the diaphragm process and 20% takes put in the membrane process.

Chlorine can also be produced by means of hydrogen chloride oxidation with oxygen from air.

Copper(II)chloride (CuCl2) is used as a cathalyser during this so-called ‘Deaconprocess’:
4HCl + O2 -> 2H2O + 2Cl2

Finally, chlorine can be produced by means of molten salts electrolysis and, mainly in laboratories, by means of hydrochloric acid and manganese dioxide oxidation:
MnO2 + 4HCl -> MnCl2 + 2H2O + Cl2

When gaseous chlorine is added to water the following hydrolysis reaction takes place:
Cl2 + H2O = H+ + Cl + HOCl

Chlorine applications

Chlorine is applied on a massive scale.

Chlorine is a extremely reactive element, causing it to quickly form compounds with other substances. Chlorine also has the ability to develop a bond between two substances that do not normally react with one another. When chlorine bonds to a substance that contains carbon atoms, organic substances are formed. Examples are plastic, solvents and oils, but also several human body fluids. When chlorine chemically binds to other elements, it often replaces a hydrogen atom during a so-called substitution reaction. Multiple hydrogen atoms in the same molecule can be replaced by chlorine atoms, causing new substances to form one after another.

Chlorine plays an significant role in medical science.

It is not only used as a disinfectant, but it is also a constituent of various medicines. The majority of our medicines contain chlorine or are developed using chlorine-containing byproducts. Medical herbs also contain chlorine. The first anaesthetic used during surgery was chloroform (CHCl3).

The chemical industry creates ten thousands of chlorine products using a little number of chlorine containing chemicals. Emaples of products which contain chlorine are glue, paints, solvents, foam rubbers, car bumpers, food additives, pesticides and antifreeze. One of the most commonly used chlorine-containing substances is PVC (poly vinyl chloride).

PVC is widely used, for example in drainpipes, insulation wires, floors, windows, bottles and waterproof clothes.

Figure 3: products containing chlorine

Chlorine-based bleach is applied as a disinfectant on a large scale. The substances are also used to bleach paper. Bleaching occurs as a result of chlorine or hypochlorite oxidation.

About 65% of industrialized chlorine is used to produce organic chemicals, such as plastics.

About 20% is used to produce bleach and disinfectants. The remaining chlorine is used to produce inorganic compounds from chlorine and several diverse elements, such as zinc (Zn), iron (Fe) and titanium (Ti).

Chlorine as a disinfectant

Chlorine is one of the most widely used disinfectants. It is extremely applicable and extremely effective for the deactivation of pathogenic microorganisms. Chlorine can be easily applied, measures and controlled. Is is fairly persistent and relatively cheap.
Chlorine has been used for applications, such as the deactivation of pathogens in drinking water, swimming pool water and wastewater, for the disinfection of household areas and for textile bleaching, for more than two hundred years.

When chlorine was discovered we did not now that disease was caused by microorganisms. In the nineteenth century doctors and scientists discovered that numerous diseases are contagious and that the spread of disease can be prevented by the disinfection of hospital areas. Extremely soon afterward, we started experimenting with chlorine as a disinfectant. In 1835 doctor and author Oliver Wendel Holmes advised midwifes to wash their hands in calcium hypochlorite (Ca(ClO)2-4H2O) to prevent a spread of midwifes fever.
However, we only started using disinfectants on a wider scale in the nineteenth century, after Louis Pasteur discovered that microorganisms spread certain diseases.
Chlorine has played an significant role in lenghthening the life-expectancy of humans.

For more information about pathogens in aquatic systems, please take a glance at pathogens in freshwater ecosystems

Chlorine as a bleach

Surfaces can be disinfected by bleaching.

Bleach consists of chlorine gas dissolved in an alkali-solution, such as sodium hydroxide (NaOH). When chlorine is dissolved in an alkalic solution, hypochlorite ions (OCl) are formed during an autoredox reaction. Chlorine reacts with sodium hydroxide to sodium hypochlorite (NaOCl). This is a extremely excellent disinfectant with a stable effect.
Bleach cannot be combined with acids. When bleach comes in contact with acids the hypochlorite becomes instable, causing poisonous chlorine gas to escape.

The accompanying underchloric acid is not extremely stable.

Figure 4: chlorine is often used as a bleach

Bleaching powder (CaOCl2) can also be used. This is produced by directing chlorine through calcium hydroxide (CaOH). The benefit of bleaching powder is that it is a solid. This makes it easier to apply as a disinfectant in medical areas, next to its use as a bleach. When bleaching powder dissolves, it reacts with water to underchloric acid (HOCl) and hypochlorite ions (OCl).

How does chlorine disinfection work?

Chlorine kills pathogens such as bacteria and viruses by breaking the chemical bonds in their molecules.

Disinfectants that are used for this purpose consist of chlorine compounds which can exchange atoms with other compounds, such as enzymes in bacteria and other cells. When enzymes come in contact with chlorine, one or more of the hydrogen atoms in the molecule are replaced by chlorine. This causes the entire molecule to change shape or drop apart. When enzymes do not function properly, a cell or bacterium will die.

When chlorine is added to water, underchloric acids form:
Cl2 + H2O -> HOCl + H+ + Cl

Depending on the pH worth, underchloric acid partly expires to hypochlorite ions:
Cl2 + 2H2O -> HOCl + H3O + Cl
HOCl + H2O -> H3O+ + OCl

This falls apart to chlorine and oxygen atoms:
OCl -> Cl + O

Underchloric acid (HOCl, which is electrically neutral) and hypochlorite ions (OCl, electrically negative) will form free chlorine when bound together.

This results in disinfection. Both substances own extremely distinctive behaviour. Underchloric acid is more reactive and is a stronger disinfectant than hypochlorite. Underchloric acid is divide into hydrochloric acid (HCl) and atomair oxygen (O). The oxygen atom is a powerful disinfectant.
The disinfecting properties of chlorine in water are based on the oxidising power of the free oxygen atoms and on chlorine substitution reactions.

Figure 5: the neutral underchloric acid can better penetrate cell walls of pathogenic microorganisms that the negatively charged hypochlorite ion

The cell wall of pathogenic microorganisms is negatively charged by nature.

As such, it can be penetrated by the neutral underchloric acid, rather than by the negatively charged hypochlorite ion.

What to do about chlorine allergy

Underchloric acid can penetrate slime layers, cell walls and protective layers of microorganisms and effectively kills pathogens as a result. The microorganisms will either die or suffer from reproductive failure.

The effectivity of disinfection is sure by the pH of the water.

What to do about chlorine allergy

disinfection with chlorine will take put optimally when the pH is between 5,5 and 7,5. underchloric acid (HOCl) reacts faster than hypochlorite ions (OCl); it is 80-100% more effective. The level of underchloric acid will decrease when the pH worth is higher. With a pH worth of 6 the level of underchloric acid is 80%, whereass the concentration of hypochlorite ions is 20%. When the pH worth is 8, this is the other way around.
When the pH worth is 7,5, concentrations of underchloric acid and hypochlorite ions are equally high.

Underchloric acid (left) : hypochlorite ions (right)

What is free and bound athletic chlorine?

When chlorine is added to water for disinfection purposes, it generally starts reacting with dissolved organic and inorganic compounds in the water.

Chlorine can no longer be used for disinfection after that, because is has formed other products. The quantity of chlorine that is used during this process is referred to as the ‘chlorine enquiry’ of the water.
Chlorine can react with ammonia (NH3) to chloramines, chemical compounds which contain chlorine, nitrogen (N) and hydrogen (H). These compounds are referred to as ‘active chlorine compounds’ (contrary to underchloric acid and hypochlorite, which are referred to as ‘free athletic chlorine’) and are responsible for water disinfection. However, these compounds react much more slowly than free athletic chlorine.

What doses of chlorine does one apply?

When dosing chlorine one has to take into acount that chlorine reacts with compounds in the water.

The dose has to be high enough for a significant quantity of chlorine to remain in the water for disinfection. Chlorine enquiry is sure by the quantity of organic matter in the water, the pH of the water, contact time and temperature. Chlorine reacts with organic matter to disinfection byporducts, such as trihalomethanes (THM) and halogenated acetic acids (HAA).
Chlorine can be added for disinfection in several diverse ways.

When ordinary chlorination is apllied, the chlorine is simply added to the water and no prior treatment is necessary. Pre- and postchlorination means adding chlorine to water prior to and after other treatment steps. Rechlorination means the addition of chlorine to treated water in one or more points of the distribution system in order to preserve disinfection.

What is breakpoint chlorination?

Breakpoint chlorination consists of a continual addition of chlorine to the water upto the point where the chlorine enquiry is met and every present ammonia is oxidized, so that only free chlorine remains.

This is generally applied for disinfection, but it also has other benefits, such as smell and taste control. In order to reach the breakpoint, a superchlorination is applied. To achieve this, one uses chlorine concentrations which largely exceed the 1 mg/L concentration required for disinfection.

Which chlorine concentration is applied?

Chlorine gas can be obtained as fluid gas in 10 bar pressure vessels.

It is highly water soluble (3 L chlorine/ 1 L water). To kill bacteria little chlorine is required; about 0,2-0,4 mg/L. the concentrations of chlorine added to the water are generally higher, because of the chlorine enquiry of the water.
Nowadays chlorine gas is only used for large municipal and industrial water purification installations. For smaller applications one generally ads calcium or sodium hypochlorite.

Which factors determine the effectivity of chlorine disinfection?

Factors which determine chlorine disinfection effectivity:
Chlorine concentrations, contact time, temperature, pH, number and types of microorganisms, concentrations of organic matter in the water.

Table 1: disinfection time for several diverse types of pathogenic microorganisms with chlorinated water, containing a chlorine concentration of 1 mg/L (1 ppm) when pH = 7,5 and T = 25 °C

Disinfection time of fecal pollutants with chlorinated water

coli 0157 H7 bacterium

< 1 minute
Hepatitis A virus about 16 minutes
Giardia parasite about 45 minutes
Cryptosporidium about 9600 minutes (6,7 days)

What are the health effects of chlorine?

The reaction of the human body to chlorine depends on the concentration of chlorine present in air, and on the duration and frequency of exposure. Effects also depend on the health of an individual and the environmental conditions during exposure.
When little amounts of chlorine are breathed in during short time periods, this can affect the respirational system.

Effects vary from coughing and chest pains, to fluid accumulation in the lungs. Chlorine can also cause skin and eye irritations. These effects do not take put under natural conditions. When chlorine enters the body it is not extremely persistent, because of its reactivity.
Pure chlorine is extremely toxic, even little amounts can be deadly. During World War I chlorine gas was used on a large scale to hurt or kill enemy soldiers. The Germans were the first to use chlorine gas against their enemies.
Chlorine is much denser than air, causing it to form a toxic fume above the soil.

Chlorine gas affects the mucous membrane (nose, throat, eyes). Chlorine is toxic to mucous membranes because it dissolves them, causing the chlorine gas to finish up in the blood vessels. When chlorine gas is breathed in the lungs fill up with fluid, causing a person to sort of drown.

What is the legislation for chlorine?

The European drinking water guideline 98/83/EC does not contain guidelines for chlorine.

WHO (World Health Organisation):
The WHO drinking water standards state that 2-3 mg/L chlorine should be added to water in order to acquire a satisfactory disinfection and residual concentration.

The maximum quantity of chlorine one can use is 5 mg/L. For a more effective disinfection the residual quantity of free chlorine should exceed 0,5 mg/L after at least 30 minutes of contact time at a pH worth of 8 or less. (WHO, Guidelines for drinking water quality. 3e editie)

The national drinking water standards state that the maximum residual quantity of chlorine is 4 mg/L. Untill recently the USA used chlorine gas extensively for wastewater treatment. Today, the use of chlorine has been forced back. This was done mostly because of dangerous disinfection byproducts, such as trihalomethanes (THM).
However, chlorine still is the main disinfectant in the USA, because it is relatively cheap.

The application of the Clean Air Act (CAA) Risk Management Plan (RMP) for the storage of toxic chemicals by EPA (june, 1999) and the re-registration of chlorine gas as a pesticide (EPA, 2001) own caused wastewater treatment plants to switch from chlorine gas to sodium hypochlorite more and more often. This is because companies do not desire to make a risk management plan for chlorine gas, as this takes up a lot of their time and money.

More information on water disinfection?:

Introduction water disinfectionNecessity water treatmentHistory of drinking water treatment

What is water disinfection?Necessity of drinking water disinfectionHistory of water disinfectionWaterborne diseasesFactors that influence disinfectionConditions of water disinfectionRegulation drinking water disinfection EUUSA

Swimming pool treatmentSwimming pool pollutionsSwimming pool disinfectionSwimming pool disinfection & health

Cooling tower waterCooling tower water pollutionsCooling tower water disinfectionCooling tower water legislation

Chemical disinfectantsChlorineSodium hypochloriteChloraminesChlorine dioxideCopper silver ionizationHydrogen peroxideBrominePeroxonePeracetic acid

Disinfection byproductsTypes of disinfection byproductsResearch on health effects of disinfection byproducts

Toxic ions hazard of irrigation water

Chlorinator system

Water is known to be a symbol of purity.

But it seems hard to believe. Especially if you’ll be looking at the present water problems, people around the globe are suffering.

Water supposed to make one healthy. But due to the contaminants that are out of our control; water might bring harm. When ingested or come in contact with our body.

Due to the rampant increase in water-related illnesses, the government and the citizens are looking for ways to treat and clean their waters.

One of the well-known water treatments being used by the government in treating the water supplied to their citizens is chlorinating the water.

Chlorine is a hazardous substance often describe as having a strong choking scent.

It is considered to be poisonous and corrosive. This chemical is generally combined with other chemicals and used to purify metals, bleach materials, mixed in order to produce another chemical and to disinfect water.

Water chlorination is the method where chlorine is added to the water — known to kill certain bacteria and other pathogens present on tap waters. And said to prevent the spread of waterborne illnesses, such as typhoid, cholera, dysentery, and numerous more.

Disinfection through chlorination could bring harm in some circumstances.

Chlorine reacts with naturally occurring sediments in the water. To produce disinfection byproducts (DBPs).

The effects depend strictly to the duration of their exposure to chemicals and the quantity ingested. When you intake large volumes of chlorinated water, it could slow below regular brain activity. Also develop heart diseases, liver or kidney cancer, unconsciousness, or even death.

Though chlorinating water seems to be a excellent method, not everybody, however, can tolerate the aggressiveness of such chemical. It may even become hazardous rather helpful. The most common complaint the majority has is developing chlorine allergies.

Effects of Chlorine Allergy

Due to the unbearable problems in water, the higher authorities chlorinate the water for the residents to enjoy a cleaner version of it.

To be consumed for their daily needs and chores.

Though we are assured that the chlorine in our water is not harmful. How could we take for granted the thought that poison or hazardous chemical will always be harmful? No matter how little the dosage is; it would surely affect our body in any way.

It would indeed fulfill its mission to clean the water. Yet, when you attempt to see how effectively it could clean metals or piping, how much more when you’re rubbing it on your body. Or worse, drinking it.

The symptoms of chlorine allergy may be considered as its effect.

A person suffering from this type of allergy may be affectedinternally or externally.

External symptoms are manifested byirritation of the eyes, dry skin, and sneezing. It also includes rashes, redness of the skin, or unbearable skin lesions.

Internal symptoms, however, are more worrying than the external ones.

What to do about chlorine allergy

It includes trouble in breathing, tightness of the chest, stuffy nose, constant coughing, nausea, and other respiratory failures. Endless term effect includes lower sperm count, kidney problems, higher risk of miscarriage, or liver problems.

What is Chlorine Allergy

When you glance into your glass of crystal clear water or to the sparkly swimming pool, thinking that it is chlorinated; your immediate thought is it’s cleaner than tap water.

However, chlorine being an aggressive type of chemical might not be excellent to everyone especially when on a higher dose.

You can’t be allergic to chlorine, yet you can be delicate or own a reaction. Whenever you are sensitive, would it be a excellent thought for you to quit swimming? No, rather you should discover and treat the reason for your sensitivity and discover a remedy.

What you believe is a chlorine allergy may really be basic asthma, work out instigated bronchoconstriction (EIB) or bronchospasm. Your runny nose may be because of other hidden sensitivity issues.

Chlorine allergy or chlorine sensitivity refers to a person’s unusual reaction once in contact with chlorine whether internal or external.

This belongs to the fourth type of allergy where the manifestation of symptoms is delayed which makes it hard for some to realize that they are already suffering chlorine allergy.

How to Prevent Chlorine Allergy Attack

Since most nations in the world use chlorination of water, what could you do?

As someone who wants clean water yet a healthy body. They tell prevention is better than cure. Preventing chlorinated water from getting into your body or your skin is something we need to put effort on.

The most recommended method of chlorine allergy prevention is installing water filters in your home. But it is significant that you invest in a brand that would do as it promises.

Our Berkey Water Filters are not only known to provide extraordinary service of contamination removal. It is known worldwide and considered as the standard setter for water filters.

What to do about chlorine allergy

This is due to its amazing ability to cleaning the water.

Unlike other filters, Berkey’s cleaning effect is unlimited. It can clean every pathogens or harmful sediments that are visible or invisible in water — even chemicals such as chlorine.

Our water filter can convert any water. Regardless of their origin into clean, potent, and best tasting water. Compared to other water filters. This method is advisable since it could clean the water in a more natural way without using chemicals or complicated processes.

Berkey Water Filters purpose to provide clean water at any way convenient to the user.

They produce portable and simple to use water filters. For the user to enjoy its purifying effect without the need for pressure or electricity.

Berkey has also developed specialty filters to aid everyone with unique water issues. For those who own fluoride issues on their waters, PF-2 fluoride filterwas made. And Sport Berkey is for those who are on the go and sports enthusiasts. For those who are suffering from chlorine allergy, Berkey presents their Berkey Shower Filter.

The Berkey Shower Water Filter has patented high purity combinations of calcium, copper, and zinc.

That is known to effectively decrease chlorine dirt and odors.

When free chlorine flows into a Berkey filter, it is changed into a benign form.

What to do about chlorine allergy

This reaction converts free-chlorine into a larger chloride element. It is too large to be absorbed by our skin.


Chlorine rash can be treated at home with over-the-counter medications. Most rashes will clear up after several days.

Over-the-counter hydrocortisone creams reduce the itching, redness, and swelling. You can get these at your local pharmacy or drug store.

They're sold under numerous brand names love Cortaid, Cortisone 10, or simply generic hydrocortisone. OTC hydrocortisone creams can be used two to four times a day. Apply a thin layer to the rash, and gently rub into the skin until it's fully absorbed.

Topical Benadryl (diphenhydramine) creams are another over-the-counter option. They assist relieve itching and irritation from the chlorine rash and can be fairly soothing. Apply them up to four times a day to the entire rash area.

Emollient lotions and creams help moisturize skin dried out by chlorine.

You can use these in between applications of medicated creams if you need them. Select a lotion that is fragrance-free and hypo-allergenic to avoid irritating your rash.

Along the same lines, you should see your physician about your rash if:

  1. Your rash isn't getting any better with home treatment.
  2. You own severe hives or hives that won't go away with treatment. Any severe allergic reaction warrants emergency treatment.
  3. You aren't certain if your rash was caused by chlorine.
  4. Your rash is spreading, getting worse, or seems severe.


Although it's sometimes called a chlorine allergy, you don't really own a true allergy to chlorine, but rather a sensitivity to it.

What to do about chlorine allergy

Chlorine rash is a type of irritant contact dermatitis.

Chlorine is a needed additive to hold swimming pool water sanitary and safe from microbes. Without chlorine acting as a sanitizer, the water in your pool or boiling tub would get nasty in a hurry. Algae, bacteria, and viruses could quickly grow unchecked.

But the downside is chlorine can be irritating to the skin, especially if you're exposed often. Chlorine strips the skin of its natural oil, called sebum. That's why your skin feels tight and dry after swimming, even if you don't develop a rash.

When the chlorine levels in the pool are especially high, love just after cleaning or a chlorine shock treatment, you're more likely to develop a chlorine rash.

But you can also develop a chlorine rash when chlorine levels are not particularly high.

The sweat, skin oils, and, yes, urine in pool water react with the chlorine creating compounds called chloramines. Consider them the by-product of chlorine mixing with the oils and sweat on your skin.

Chloramines are what give swimming pools and boiling tubs their distinctive odor, and can be fairly irritating to the skin. So, you can still develop a chlorine rash after swimming in pools where the chlorine level is low.

Even if you rinse off after swimming, you may still develop a chlorine rash.

Chlorine is extremely hard to completely rinse off from the skin and hair. That's why you may still "smell love pool water" even after showering.

Sodium + Chlorine:
Pass the Salt, Please

Sodium is a silver-colored metal which is soft enough to cut with a knife. It is an extremely reactive metal, and is always found naturally in ionic compounds, not in its pure metallic form. Pure sodium metal reacts violently (and sometimes explosively) with water, producing sodium hydroxide, hydrogen gas, and heat:

2Na(s) + 2H2O(l) ——> 2NaOH(aq) + H2(g)

Chlorine is apoisonous, yellow-green gas, with a extremely sharp odor, and was used in gas warfare during World War I.

Sodium and chlorine react with each other, however, to produce a substance that is familiar to almost everyone in the world: sodium chloride, or table salt:

2Na(s) + Cl2(g) ——> 2NaCl(s)

It is simple to see why this reaction takes put so readily when we glance at it on an atomic level: sodium has one electron in its outermost (valence) shell, while chlorine has seven electrons in its valence shell.

When a sodium atom transfers an electron to a chlorine atom, forming a sodium cation (Na+) and a chloride anion (Cl), both ions own finish valence shells, and are energetically more stable.

The reaction is extremely exothermic, producing a bright yellow light and a grand deal of heat energy.

In the following demonstrations, a 2.5 liter bottle is filled with chlorine gas. A coating of sand on the bottom of the bottle absorbs some of the heat energy produced during the reaction, and prevents it from breaking.

A little piece of freshly-cut metallic sodium is placed in the flask, and then a little quantity of water is added, which reacts with the sodium and causes it to become boiling. The boiling sodium then reacts with the chlorine, producing a bright yellow light, a grand deal of heat energy, and fumes of sodium chloride, which deposits on the walls of the bottle.

In the first video clip, the sodium flares up almost immediately upon reaction with the water, and "burns out" quickly. (Don’t blink, or you’ll miss it.) In the second, water is added twice, to produce one short flash, followed by a much longer one.

(This reaction can also be done with molten sodium, but I’ve never been courageous enough to attempt that.)

Video Clip 1: Genuine, 679 KB

Video Clip 2: Genuine, 1.74 MB

!!! Hazards !!!

Do not expose sodium metal to water! The reaction of sodium and water produces hydrogen gas and heat, which is not a excellent combination! Sodium must be stored under mineral oil, or some other high-molecular weight hydrocarbon.

Chlorine gas is toxic, and extremely irritating to the eyes and mucous membranes.

This reaction evolves a grand deal of heat energy; make certain that the flask has no cracks in it.


Bassam Z.

Shakhashiri, Chemical Demonstrations: A Handbook for Teachers of Chemistry, Volume 1. Madison: The University of Wisconsin Press, 1983, p. 61-63.

Lee R. Summerlin, Christie L. Borgford, and Julie B. Ealy, Chemical Demonstrations: A Sourcebook for Teachers, Volume 2, 2nd ed. Washington, D.C.: American Chemical Society, 1988, p. 56-57.


John Emsley, The Elements, 3rd ed. Oxford, Clarendon Press, 1998, p.

56-57, 194-195.

David L. Heiserman, Exploring Chemical Elements and their Compounds. New York: TAB Books, 1992, p. 43-48, 70-74.

Martha Windholz (ed.), The Merck Index, 10th ed. Rahway: Merck & Co., Inc., 1983.

Chlorine rash is a red, itchy rash that appears within a few hours after swimming in chlorinated pools or boiling tubs. The rash can be raised and scaly, and the skin may be swollen or tender. In some cases, hives also develop. Chlorine rash is caused when the skin becomes irritated by chlorine, and can generally be treated with over-the-counter hydrocortisone creams. It typically clears up within a few days.