Finishing
Disinfection of water by chlorination. The harm of chlorinated water The harm of chlorinated water

Disinfection of water by chlorination. The harm of chlorinated water The harm of chlorinated water

Water is purified step by step by settling, oxidizing with atmospheric oxygen, coagulation, again settling, filtering. Why disinfect water with chlorine? What is the reason for the need for chlorination, what conditions make it indispensable? The fact is that bacteria and viruses are destroyed at all preliminary stages of purification by no more than 85-90%, and among the remaining microorganisms there may well be dangerous to human health. In addition, chlorine is one of the strongest oxidizers, and disinfecting drinking water with chlorine binds some of the remaining impurities and destroys others. Not only chlorine is used as an oxidizing agent. Potassium permanganate, hydrogen peroxide, sodium hypochlorite, calcium hypochlorite, chlorine dioxide, ozone are widely used. Ozone and chlorine are most often used in municipal water treatment. The fact is that water is always different, and methods are selected for each specific source water. At the same time, chlorine is an almost universal method suitable for treating any source water. The cost, the possibility of automating the supply of a reagent in given quantities, the conditions for the supply and transportation of chlorine, and the very degree of water purification make chlorine indispensable at the present stage of development of water purification technologies specifically for mass widespread purification, for replication of complex water purification systems.

Disinfection of tap water with chlorine has been used in the world since the end of the nineteenth century. After the cholera epidemic in England in 1870, chlorination began to be used to disinfect water. At the beginning of the 20th century, water chlorination also came to Russia, first to large cities, and then everywhere to disinfect tap water at municipal water treatment plants. It was chlorination that stopped the spread of intestinal infections during the period of industrial development and the massive widespread increase in the number of city dwellers in connection with the industrial revolution.

Chlorine and tap water, and drinking, and technical, and water in swimming pools.

Why is chlorine dangerous for humans? Information on the statistics of diseases in the public domain is sufficient. And it is easy to find, we will indicate only the obvious ones. Water disinfection with chlorine suppresses the natural bacterial background of the human digestive system. The bacteria inside us do a great job, helping to digest fiber, curdling milk proteins, producing vitamins and beneficial minerals, being part of the human immune system. Chlorine in drinking water seriously depresses the immune system.

Disinfection of water with chlorine has a serious drawback when boiling. Chlorine, reacting with a number of mineral impurities, forms serious poisons. Chlorine is a strong allergen and a catalyst for other allergies. Sometimes it is enough for an allergy sufferer to change the drinking water to get relief from the underlying disease. This is important, especially given that chlorination will be around for a long time to come.

Chlorine has a number of other disadvantages - high toxicity, high corrosiveness of aqueous solutions, and explosiveness. It's no secret that during the First World War, chlorine was used as a chemical warfare agent on the battlefields. However, the methods of using chlorine for the purification of drinking, industrial water and the disinfection of industrial and domestic wastewater have long been developed, so the use of chlorine in water treatment has not yet been abandoned.

The quality of water disinfection with chlorine and its compounds in practice is determined on the basis of an analysis of the amount of dosed chlorine and residual chlorine in purified water. If there is residual chlorine, then the concentration was enough to complete the processes of oxidation of impurities. Also take into account the data of the pH index, water temperature, reaction time and some additional parameters. There are no statistics on how much chlorine should be dosed in each specific case, because water is always different. The calculation is always made by design methods, and when using the dosing of chlorine or chlorine-containing substances using special filter loads, the data of the manufacturer of the loads are based.

Water disinfection with chlorine is used depending on the nature of the pollution and the characteristics of the water treatment equipment for preliminary chlorination and subsequent chlorination.

Pre-chlorination is carried out before other methods of purification, with significant water pollution. Subsequent purification steps usually remove excess chlorine.

Subsequent chlorination is used to provide guarantees for the sanitary quality of water. The amount of residual chlorine is intended, in this case, to protect the consumer from contaminants that enter the water during the transportation of water in water pipeline systems.

Excess chlorine is removed by dechlorination methods. Use aeration or reducing agents - chemicals that remove chlorine.

When disinfecting drinking water with chlorine, it is easily removed using a reverse osmosis system, a flow system, a jug. How to choose a filter for drinking water can be read in the appropriate section of the site.

When using an individual water treatment system in a private house, equipment with chlorine dosing may also be installed. How to guarantee the disinfection of water using chlorine in this case, the specialists of our company can suggest.

Disinfection of drinking water by chlorination has become a real achievement of mankind, along with the discovery of penicillin. The surprising factor is that chlorine, used in war as a weapon, began to serve peaceful purposes, and, once killing, now saves.

The reason for this procedure is due to the fact that natural fresh water contains countless microorganisms that can cause infectious diseases that are dangerous to human life.

There are several ways to destroy the source of infection: boiling, oxidation or irradiation. Boiling and irradiation is irrational. What remains is the oxidation method, and the cheapest oxidizing agent is chlorine.

That is why, for sanitary purposes, for entering the water supply system, it is chlorinated. Scientists are trying to develop a more rational and harmless way, however, so far to no avail.

In some places, water is ozonized, but ozone is not stored in the water and it is likely that water that has reached the consumer through the tap will carry pathogens.

What rules need to be followed

Photo: chlorine analyzer

The exact dosage of chlorine is extremely important. With insufficient chlorination, harmful bacteria can again fill the water. With excessive chlorination, there is a danger of excessive human consumption of chlorine. Drinking water loses its taste and becomes hard.

The norm, which serves as the unit of account for chlorination, is set from the most polluted indicator.

Sufficient norm of oxidizing agent in water varies within 0.5 mg/l. An important factor is the thorough mixing of the treated water with the reagent and being in contact with it for at least half an hour before consumption.

Chlorination Methods

Photo: chlorination of drinking water with sodium hypochlorite

Chlorination of drinking water with sodium hypochlorite provides reliable disinfection against all pathogenic viruses, bacteria and protozoa. Hypochlorite is safe as it does not have explosive characteristics.

In addition, hypochlorite is more active than chlorine. Hypochlorite is practically non-toxic. Unlike gaseous chlorine, it is easy to store, use, and dispose of.

In recent years, chemical plants have produced 60 percent more sodium hypochlorite than bleach.

The main advantages of sodium hypochlorite:

the oxidizing agent does not require the storage and transportation of chemicals;
the reagent is effective against the prevailing number of bacteria.

This type of chlorination also has a number of disadvantages:

activity is lost during a long period of storage;
powerless against cysts;
dangerous due to the ability to release gaseous chlorine;
accumulation of chlorates at a concentration in the solution of more than 9 pH and 450 mg/l;
requires additional measures for the possibility of storage, measures for purification from heavy metal ions.

Photo: lime production

Bleach is poison. It is obtained by exposing slaked dry lime to chlorine gas. Viniplast, rubber and lead are not subject to lime attack.

Chlorination of drinking water with bleach is a fairly popular method of disinfection in water pipes. Reinforced concrete or wooden tanks are used for storage and transportation of lime.

Inside, the surface is faced with acid-resistant tiles or treated with cement. Active chlorine contained in lime must be at least 40 percent.

When chlorinating drinking water with bleach, a 2% solution is used, that is, for every 100 liters of solution, 5 kg. bleach.

The huge costs of making bleach, the low content of active chlorine in lime and its rapid loss from water make such disinfection irrational compared to other methods.

Another common water disinfection method is chlorination with chlorine dioxide. Chlorine dioxide has several advantages over other reagents:

high deodorizing and bactericidal action;
improvement of organoleptic properties of water;
no need to transport liquid chlorine;
the absence of chlorine organics in the products of processing;
does not impair the taste of water, has no smell.

Chlorine dioxide has only one drawback: a complex technology due to increased explosiveness, and, as a result, the high cost of the method.

Dechlorination

Dechlorination is the process of purifying water from chlorine by introducing into water that has undergone chlorination, substances that can remove and bind excess chlorine.

Such substances can be sodium sulfite, sulfur dioxide, sodium hyposulfite and others. Sodium sulfite can have bacterial contamination and therefore can re-contaminate the water.

One of the highest quality industrial cleaning methods is a carbon filter. Coal eliminates unpleasant taste and smell, removes chlorine and organic compounds.

Dechlorination with coal occurs by a chemical reaction during which the coal surface is oxidized. Dechlorination with coal is the more effective, the higher the temperature and the lower the pH of the process.

After the passage of drinking water through the filter, impurities are removed, which are washed into the drain when the filter is backwashed.

Since the dechlorination process oxidizes the coal and destroys its structure, backwashing ensures that the dechlorination is effective.

Photo: charcoal filter

You can dechlorinate drinking water at home in fairly simple ways:

by boiling drinking water for twenty minutes;
One vitamin C tablet can dechlorinate up to 400 liters of water;
by installing to filter all the water in the house. It should be noted that the carbon filter requires special care, rinse every six months and change depending on the filter brand. However, such dechlorination provides high quality 100% filtration;
by installing the filter directly under the sink, which will significantly save the family budget and purify the vital source of moisture.

Photo: reverse osmosis filter

Instructions for chlorinating water at home

Chlorinating water at home is usually not a typical problem, as we all use tap drinking water that is already commercially chlorinated.

However, if the water needs to be disinfected, it is important to observe the following measures:

the amount of chlorine for disinfection depends on the temperature and duration of water settling. The usual dosage is 1 mg of chlorine per liter of water with an average settling time of 30 minutes;
the amount of chlorine should be increased in case of settling for more than half an hour, at a water temperature below 10 degrees and an acidity above 7.

Thus, in order to chlorinate water at home, it is necessary to know and take into account all indicators of water, since chlorine in case of an overdose can cause poisoning, and in case of an insufficient amount of the reagent, disinfection will not be effective.

Important! After chlorination of water, it is necessary to dechlorinate the water in order to make drinking water suitable for consumption.

Chlorination in a well

Photo: chlorination of water in a well

Periodic maintenance of the well is necessary in case of drinking water from it. The control of disease-causing organisms that can live in a drinking source is a serious issue that prevails over the problems of removing weeds, leaves and harmful insects from the site.

An ordinary bleach solution, such as 2/3 basic sodium hypochlorite salt or bleach, may be suitable. To make a solution, 15 mg of a disinfectant is diluted in a liter of water.

Calculate the amount of solution based on the formula: P=EC100/N, where P is the solution for disinfection, E is the volume of water in the well, C is the amount of active chlorine in the well, H is the amount of active chlorine in the solution..

The volume of water in a well can be calculated from the fact that a ring of a well with a height of one meter and a diameter can hold approximately 700 liters of water.

Chlorination is carried out in the following steps:

cleaning the walls of the well. First, water is pumped out, then the walls are treated with a solution of bleach;
refill the well. Pour a solution of lime 200 mg per liter of cold water;
the solution is poured into the well;
the well is closed for 10-12 hours;
the next day, the procedure is repeated;
pump out water, thoroughly wash the well;
before using drinking water, you need to wait a week from the moment of the last disinfection.

in container

When chlorinating water in a container, it must be calculated based on the dosage set out in the instructions for chlorination at home, taking into account the volume of the container.

Benefit and harm

Photo: chlorination of water in a tank

The benefit of chlorination is to purify water from dangerous microorganisms, which, before the discovery of this method of disinfection, led to mass diseases of people, epidemics, sometimes with a threat to life.

However, despite the advantages of chlorination, you should know that it also has a number of significant disadvantages. When drinking water is treated with chlorine, substances that are poisonous and dangerous to humans are formed.

Scientists have found that the incidence of cancer is directly related to a certain concentration of chlorine in the water. When water is chlorinated, toxins are formed that have a devastating effect on human health.

These are mutagenic substances, immunotoxic and carcinogenic substances. Water treated with chlorine can cause not only malignant tumors, but also affect the general condition of the skin, hair structure, heart, and mucous membranes of the eyes.

Drinking water is the source of human life. The problem of water disinfection is one of the urgent problems of all mankind, as the quality of its natural sources is constantly deteriorating.

Recently, more and more new methods of water disinfection are being researched and applied. However, their use is much more expensive than chlorination and it does not provide a 100% guarantee against re-contamination of drinking water after disinfection.

In Peru, a cholera outbreak broke out due to the refusal to chlorinate water in order to prevent cancer. Thus, chlorination remains practically the only reliable method of water disinfection.

Video: Danger for kidney patients

From each water tap flows water saturated with a terrible poison used during the war as a chemical weapon, its name is chlorine.

Why is there chlorine in the water?

Before water reaches our taps, it passes through a mass of sewage treatment plants. And even after that, it contains a huge number of pathogenic microorganisms and a variety of viruses. That is why in our country tap water lends itself to chlorination.

Chlorine is the strongest bactericidal agent, and besides, it is also the cheapest. Not all of the chlorine added to water is used to ensure its epidemiological safety; some can enter into a chemical reaction with various organic substances and form a really dangerous mixture. The products of such undesirable reactions are the strongest mutagenic, carcinogenic, and simply toxic compounds, such as dioxin, chloroform, etc.

Beware of CHLOR!

Numerous studies have repeatedly proven the negative effect of chlorine and its compounds on the human body. Excess levels of these substances in water can lead to:
allergies
Inflammation of the mucous membranes
Liver and kidney damage
metabolic disorders
Violation of the CCC
CNS damage
Oncological diseases
The occurrence of malformations in the fetus during intrauterine growth, etc.

This list is far from complete, but it also makes it possible to assess the degree of toxicity of a highly volatile compound that affects the human body every day, even during banal hand washing. To give a colorful example, Japan has long used chlorine-free wastewater treatment plants. This practice has led to an increase in average life expectancy by 10 years and a decrease in the number of visits to medical institutions by 3 times.

Is there salvation?

Despite the huge number of negative qualities of chlorine, tap water is chlorinated in almost all countries. These include Spain, South Korea, England and even the United States. The difference is only in the permissible norms of chlorine and other compounds in water. Let's compare the norms accepted in the USA and Russia.

The Russian Ministry of Health is confident that citizens are not in any danger if the water contains no more than 350,000 µg/l chlorides and 200 µg/l chloroform. American colleagues have a different opinion on this matter: in the USA, the content of chloroform in water in general is unacceptable, and the amount of chlorides should not exceed 250,000 µg/l.
By the way, WHO supports America's policy regarding the content of chlorides in tap water, but at the same time, it allows the presence of chloroform in it within the limits 200 µg/l.

Along with this, in most countries, tap water is used only for domestic purposes, and for drinking there is specially purified or bottled water. In our country, they drink such water, sometimes raw, but mostly boiled. Is it harmful?

Is boiled water safe?

It is pointless to talk about the dangers of regular use of raw water for the body, since the risk of getting the disorders of the functioning of organ systems described above increases significantly, and all sorts of problems with the gastrointestinal tract associated with the intake of microorganisms are added to them.

The only possible way to use raw tap water is to pre-treat it at home from harmful chlorine. Various filters are used for this purpose.

Many people simply defend tap water, believing it helps to remove the chlorine from it. The method has the right to life, since free chlorine is a gas, so over time it can completely evaporate from the water. The duration of settling depends on the amount of liquid and the shape of the vessel in which it is located, but should not exceed a day, since after 24 hours the water becomes bacteriologically hazardous. The larger the area of the neck of the container with water, the faster the gas will evaporate. The process can be accelerated by boiling, then in a matter of minutes the water will lose almost all free chlorine.

But with boiled water, everything is not so simple. The main task of boiling is to kill the microflora, for its full implementation, the water should boil for about half an hour. Long-term preservation of high temperatures provokes an accelerated course of chemical reactions between free chlorine that has not yet volatilized, its compounds ( their amount is in the range of 0.8 - 1.2 mg / l) and organic matter. As a result, highly toxic compounds are formed, and their number is directly proportional to the boiling time. Thus, boiling does not solve the problem of chlorinated water, but only exacerbates it.

"SPA treatments" with chlorine

An important aspect of considering the problem of the negative impact of chlorinated water on the human body is the ability of this substance to worsen the condition of the skin and hair.

Hair can be called a kind of indicator of the quality of tap water. If the chlorine content in it is increased, this will certainly affect the condition of the hairline in the form of:
Increased brittleness, dryness of hair and the occurrence of the so-called "straw" effect,
Difficulties with installation
Rapid loss of shine and hair color after dyeing,
The appearance of split ends,
Hair loss.

Chlorides, including perchloric acid, contained in water, adversely affect the scalp, face and body. They can provoke:
appearance of dandruff
peeling and dryness of the skin, which even good moisturizers cannot cope with,
irritation to cosmetics, even long-used,
the appearance of age spots and mimic wrinkles,
the development of allergic reactions and various inflammations, manifested in redness and itching of the skin. In rare cases, regular washing with chlorinated water can lead to coughing fits and choking.

Thus, chlorinated water is a real problem in modern life. Everyone knows how to fight, but many ignore. Think about your health, use filters or buy purified water.

We use tap water every day. We wash it, we drink it. Often we do not even boil. How safe is it for health? Rospotrebnadzor data on the quality of drinking water and the cleanliness of the water supply sometimes do not inspire optimism.

How water is purified

Experts from the World Health Organization are confident that there are few water bodies left in nature, the water of which is safe and beneficial for humans. Most often, large and small cities take water from rivers and reservoirs that have already been polluted. Therefore, first the water is purified at special stations. It is chlorinated, ozonated, coagulated, settled, filtered, chlorinated again, and only then the water goes to the water supply.
During the melting of snow and during floods, I additionally treat the water with activated carbon and potassium permanganate or additional chlorination.

Chlorination

It is around chlorination that many copies have been broken. Chlorine kills any bacteria - even cholera, dysentery and typhoid fever, but it also harms a person. Chlorine dries the skin, is dangerous for allergy sufferers and people prone to asthma.
Doctors are concerned not so much with residual chlorine as with its compounds. For example, Roskontrol experts believe that the reaction of chlorine with organic substances produces trihalomethanes, carcinogens that can promote the formation of cancer cells.

When boiling in chlorinated water, dioxins are formed - toxins that suppress human immunity. These impurities can lead to liver and kidney disease and other health complications. Of course, there will be no immediate effect from them, but in the long run, health can be undermined.
Dr. Herbert Schwartz of Cumberland College (USA), considers water chlorination so dangerous that it requires a ban.

Pollution from the plumbing

But that's not all. From the stations, purified, disinfected and safe water that meets all SanPiNs enters the water supply system and passes through rusty, old, and sometimes leaky pipes several kilometers to the apartment. Only in Moscow, the total length of the water pipeline is 9,000 kilometers. This is more than the distance from the capital to Vladivostok. Along the way, water washes away dirt and rust from the pipe walls.

As a result, a “cocktail” of chemical compounds is poured from the tap. Not without reason in SanPiN the maximum permissible concentrations of these substances are listed on almost 20 pages.

In the water can be and are most often present: chlorides, sulfates, sulfides (hydrogen sulfide), iron, manganese, ammonium (ammonia), silicon and aluminum. And there can be benzapyrene, benzene, cadmium and magnesium, nitrates, pesticides, phenols, surfactants and petroleum products.

And this despite the fact that in Moscow, for example, microbiological indicators of water are checked 2 times a day, organoleptic - up to 12 times, and indicators for residual chlorine - every hour. Every day, 1000 chemical, 100 bacteriological and 20 hydrobiological analyzes are carried out at the stations.

According to the research of Oleg Mosin, Candidate of Chemical Sciences, tap water at the outlet of stations in Moscow meets the standards, and in some parameters surpasses the water of European cities. But even he expresses concern about the quality of water running from the tap and believes that the situation in the regions is worse.
Yes, all these dangerous substances are present there in extremely small doses. But they do exist!

Don't panic

But let's not rush and record ourselves as sick.
According to Rosstat, in 2011 the average life expectancy in Russia was 69.83 years. In 2013, it increased to 70.8 years, and in 2014 to 71 years, which is higher than in 1990.

Thirdly, it is with drinking water that the population receives such an essential trace element as fluorine - it is added to water.

The lack of fluorine causes problems with teeth, joints, suppresses hematopoiesis and immunity, and causes problems with healing of fractures.

Fourthly, in addition to fluorine, a person needs in microdoses such substances as arsenic, the lack of which causes the development of allergic reactions, chromium, which is involved in the metabolism of carbohydrates and is necessary for the functioning of the heart, silicon, without which hair falls out. We also need vanadium, without which diabetes and atherosclerosis can develop.

In addition, in ordinary tap water there are other salts that are vital for a person. In 2003, in Rome, at a symposium of the Center for Environment and Health, interesting facts were heard. It turned out that residents of the northern regions of the Irkutsk region, who drink harder water, ceteris paribus, are less likely to suffer from goiter, high blood pressure, diseases of the stomach and intestines, and pregnant women and newborns have fewer complications.

What to do?

If you think your tap water is of poor quality, you can switch to bottled water. But only if you are sure of the manufacturer. After all, the fact that it is the manufacturers of bottled water who most often talk about the dangers of tap water cannot but be alarming.

To make tap water safer, you need to drain it for a few minutes, then let it stand for at least a day, and only then filter it.

Not all filters are equally useful. For example, US scientists are sure that carbon filters are harmful. Coal gets into the water and when boiled forms dioxide.

Remember that filters costing more than $300 produce bacterial water purification.
But both scientists and doctors agree that any filter is better than nothing. Just do not forget to wash and change the filters, otherwise the positive effect may become negative.

11.02.10

Why is chlorination of tap water dangerous?

Water chlorination is the most common method of drinking water disinfection using gaseous chlorine or chlorine-containing compounds that react with water or salts dissolved in it. As a result of the interaction of chlorine with proteins and amino compounds contained in the shell of bacteria and their intracellular substance, oxidative processes, chemical changes in the intracellular substance, disintegration of the cell structure and death of bacteria and microorganisms occur.

Disinfection (disinfection) of drinking water is carried out by dosing chlorine, chlorine dioxide, chloramine and bleach (not to be confused with the term purification of drinking water from lime). The required dose of the dosed substance is determined by test chlorination of water: it is determined by the chlorine absorption of water (the amount of chlorine required to bind the organic compounds contained in the water).

In order to destroy microbes, chlorine is introduced in excess so that 30 minutes after chlorination of water, the content of residual chlorine is not less than 0.3 mg / l. In some cases, double chlorination of water is carried out - before filtration and after water purification. Also, in epidemiological disasters, superchlorination is carried out, followed by dechlorination of water.

For water chlorination at water treatment plants, liquid chlorine and bleach are used (for low-capacity stations).
Chlorination of water with liquid chlorine. When chlorine is added to water, hypochlorous and hydrochloric acids are formed.

HOS1 h * H + + OS1-.

The hypochlorite ions OC1 ~ resulting from the dissociation of hypochlorous acid have, along with undissociated molecules of hypochlorous acid, a bactericidal property.

The sum of C12 + HOC1 + OS1- is called free active chlorine.

In the presence of ammonium compounds in water or with a special introduction of ammonia into water (ammonization of water - see § 114), monochloramines NH2CI and dichloramines NHCb are formed, which also have a bactericidal effect, somewhat less than free chlorine, but longer. Chlorine in the form of chloramines, in contrast to free chlorine, is called bound active chlorine.

The amount of active chlorine required for water disinfection should be determined not by the number of pathogenic bacteria, but by the entire amount of organic substances and microorganisms (as well as inorganic substances capable of oxidation) that may be in the chlorinated water.

The correct administration of the dose of chlorine is extremely important. An insufficient dose of chlorine can lead to the fact that it does not have the necessary bactericidal effect; an excessive dose of chlorine worsens the taste of water. Therefore, the dose of chlorine should be set depending on the individual properties of the treated water based on experiments with this water.

The calculated dose of chlorine in the design of a disinfection plant should be taken based on the need to purify water during its maximum pollution (for example, during floods).

An indicator of the sufficiency of the accepted dose of chlorine is the presence in the water of the so-called residual chlorine (remaining in the water from the administered dose after oxidation of the substances in the water). According to the requirements of GOST 2874-73, the concentration of residual chlorine in water before it enters the network should be in the range of 0.3-0.5 mg/l.
The content of free residual chlorine in drinking water is regulated by SanPiN 2.1.4.1074-01 "Drinking water. Hygienic requirements for water quality in centralized drinking water supply systems. Quality control" (the content of free residual chlorine in water is 0.3 - 0.5 mg / l) and SanPin 2.1.4.1116 - 02 “Drinking water. Hygienic requirements for the quality of water packaged in containers. Quality control” (content of free residual chlorine in water is not more than 0.05 mg/l). The limiting sign of the harmfulness of the substance for which the standard is set is organoleptic (although this is far from the case ...).

Chlorine is the worst enemy of our time since it has been used as a drinking water disinfectant since 1904. By preventing some diseases, it is the cause of other, more terrible diseases: heart problems, cancer, and premature aging. Ironically, even chlorine, widely used as a water disinfectant, turns out to be a dangerous carcinogen.

On the one hand, water chlorination has saved humanity from the risk of infectious diseases and epidemics. On the other hand, scientists in the 70-80s found that chlorinated water contributes to the accumulation of carcinogens in the water. Among the population consuming chlorinated drinking water, cases of cancer of the esophagus, rectum, breast, larynx, and liver disease have been identified. Because when chlorine interacts with organic substances in water, chemicals are formed. These substances are trichlomethanes- are carcinogenic, which has been proven by scientists empirically. After all, as you know, chloroform even causes cancer in rats.

This effect of the harmful effects of chlorine can be caused in two ways: when chlorine enters the body through the respiratory tract, and when chlorine enters through the skin. Scientists all over the world are investigating this problem. They link many dangerous diseases to human exposure to chlorine or the harmful by-products of water chlorination. These diseases include Key words: bladder cancer, stomach cancer, liver cancer, rectal and colon cancer. But not only the digestive organs suffer.

What is the problem?

The most important problem of this method is the high activity of chlorine, it enters into chemical reactions with all organic and inorganic substances in the water. In water from surface sources (which are mainly sources of water intake) there is a huge amount of complex organic substances of natural origin, and in most large industrial cities, dyes, surfactants, oil products, phenols, etc.

When chlorinating water containing the above substances, chlorine-containing toxins, mutagenic and carcinogenic substances and poisons, including dioxides, are formed, namely:

Chloroform, which has carcinogenic activity

Dichlorobromomethane, bromomethane chloride, tribromomethane - having mutagenic properties

2,4,6-trichlorophenol, 2-chlorophenol, dichloroacetonitrile, chlorhieredin, polychlorinated biphenyls - which are immunotoxic and carcinogenic substances

Trihalomethanes - carcinogenic compounds of chlorine

These substances have a slow killer effect on the human body. Purification of drinking water from chlorine does not solve the problem, since many of the dangerous compounds formed in water during its chlorination enter the human body through the skin, while washing, taking baths or visiting the pool. According to some reports, an hour of taking a bath containing an excess of chlorinated water corresponds to ten liters of drunk chlorinated water.

The first attempts to link the oncological incidence of the population with the quality of drinking water were made as early as 1947. But until 1974, water chlorination was not associated with oncology. It was believed that chlorinated water does not adversely affect human health.

Unfortunately, data on the relationship between the consumption of chlorinated drinking water from surface water sources and the frequency of malignant neoplasms in the population began to accumulate only from the 1970s. Therefore, there are still different points of view on this matter. According to some researchers, from 30 to 50% of cases of malignant tumors can be associated with the use of contaminated water. Others have calculated that consumption of river water (compared to groundwater) can lead to a 15% increase in cancer incidence.

What is the danger of chlorine entering the human body

The side effect of the harmful effects of chlorine can be caused in two ways: when chlorine enters the body through the respiratory tract, and when chlorine enters through the skin. Scientists all over the world are investigating this problem. They link many dangerous diseases to human exposure to chlorine or the harmful by-products of water chlorination. These diseases include: bladder cancer, stomach cancer, liver cancer, rectal and colon cancer.

But it's not just the digestive system that suffers.. Also, chlorine can cause heart disease, atherosclerosis, anemia, high blood pressure. In addition, chlorine dries the skin (remember the feeling of tightness of the skin after the pool), destroys the structure of the hair (they begin to fall out more, become brittle, dull, lifeless), irritates the mucous membrane of the eyes.

US epidemiologists conducted a study: they compared a map of water chlorination with a map of the distribution of cancers of the bladder and digestive organs. A direct relationship was revealed: the higher the chlorine content in the water, the more common the disease.

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British scientists from the University of Birmingham said that the consumption of chlorinated water during pregnancy can lead to the birth of children with severe birth defects - in particular, with heart and brain defects.

Led by Juni Jaakkola, they studied data from 400,000 babies to find out how the 11 most common birth defects are associated with high, medium or low levels of chemicals that appear when drinking water is chlorinated.

As you know, chlorination is a fairly common method of disinfection, which leads to a significant reduction in infections transmitted with drinking water. But one of the disadvantages of this method is the formation of by-products, most of which are the so-called trihalomethanes, in particular chloroform, dichlorobromomethane, dibromochloromethane and bromoform.

The study found that high levels of by-products of chlorination from 50 to 100% increased the risk of three birth defects - ventricular septal defect (a hole in the septum between the ventricles of the heart, which leads to mixing of arterial and venous blood and chronic lack of oxygen), as called cleft palate (cleft palate), as well as anencephaly (complete or partial absence of the bones of the cranial vault and brain).

"The biological mechanisms that lead to birth defects at high levels of chlorine by-products remain unknown. But our study not only provides additional evidence that chlorine can cause birth defects, but also shows that the presence of its by-products may be associated with some specific vices,” Iaakkola says.

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The dangers of chlorine for health a person should not be underestimated, doctors say. Despite the fact that water treatment plants use relatively low concentrations, even these are harmful to animal and human health. Inhalation of high concentrations of chlorine can be fatal to humans and cause a variety of illnesses, from headaches to neurotoxic reactions, and possibly even the development of cancerous tumors.

Moreover, as experts note, water toxins enter the body not only through the respiratory system. Chlorine deprives the skin of its natural fatty membrane, dries, causes itching and premature aging. Even hair under the influence of chlorinated water becomes dry and brittle.

Chlorination of water is the most popular way to disinfect it, but not the safest. The main risks of tap water consumption are related to the by-products formed by chlorine when combined with other substances. There is evidence that this may contribute to the development of cancer. Moreover, poor quality water is the cause of 90% of diseases, and consumption of good quality water can extend life by 5-8 years.

Based on materials: www.bibliotekar.ru, www.ekomarket.ru, RBK.ru, RIA Novosti