How to maintain normal pH. Normal urine pH: what might an acidic or alkaline reaction in the analysis indicate? Acidity pH is normal

Why is it useful to know about pH??

Why does pure water cause the most pain?

Why do many cosmetic creams cause more harm than good?

How to help the body cope with calcium deficiency and protect your bones and teeth from destruction?

This is discussed in the article " What is pH?" Excerpts from which are given below.

pH correction can be done using living and dead water, which, unlike alkalis and acids, have alkaline and acidic properties, respectively, but contain a minimal amount of other elements besides water. The presence of other elements is determined by the material from which the electrodes are made. When using carbon or graphite electrodes, the best results are obtained. Although, in some special cases, the use of electrodes made of other materials may be preferable.

To properly use living and dead water, it is very useful to know what pH is and when it needs to be adjusted.

Living water has a pH of 8.0-9.0

Dead water has a pH of 5.0-6.0
"What is pH?

The ratio of acid and alkali in any solution is called acid-base balance (ABC), although physiologists believe that it is more correct to call this ratio the acid-base state.
KSHR is characterized by a special pH indicator (power Hidrogen - “hydrogen power”), which shows the number of hydrogen atoms in a given solution. At a pH of 7.0 they speak of a neutral environment.

The lower the pH level, the more acidic the environment (from 6.9 to O). An alkaline environment has a high pH level (from 7.1 to 14.0).
The human body is 70% water, so water is one of its most important components. The human body has a certain acid-base ratio, characterized by pH (hydrogen) value.
The pH value depends on the ratio between positively charged ions (forming an acidic environment) and negatively charged ions (forming an alkaline environment).
The body constantly strives to balance this ratio, maintaining a strictly defined pH level. When the balance is disturbed, many serious diseases can occur.

Maintain proper pH balance to maintain good health.
The body is able to properly absorb and store minerals and nutrients only with the proper level of acid-base balance. It is in your power to help your body receive, rather than lose, nutrients. For example, iron can be absorbed by the body at a pH of 6.0 - 7.0, and iodine at a pH of 6.3 - 6.6.
Our body uses hydrochloric acid to break down food. In the process of vital activity of the body, both acidic and alkaline decomposition products are required, and 20 times more of the former are formed than the latter. Therefore, the body’s defense systems, which ensure the invariability of its ASR, are “tuned”, first of all, to neutralize and remove, first of all, acidic decomposition products.

The main mechanisms for maintaining this balance are:

blood buffer systems (carbonate, phosphate, protein, hemoglobin);

respiratory (pulmonary) regulation system;

renal (excretory system).

It is in your best interest to maintain the correct pH balance.
Even the “most correct” program for selecting medicinal herbs will not work effectively if your pH balance is imbalanced.
How the body manages acidity levels:

Releases acids - through the gastrointestinal tract, kidneys, lungs, skin

Neutralizes acids - with the help of minerals: calcium, magnesium, potassium, sodium

Accumulates acids - in tissues, primarily in muscles

1. Saliva is a predominantly alkaline reaction (pH fluctuation 6.0 - 7.9)

2. Liver - the reaction of gallbladder bile is close to neutral (pH about 7.0), the reaction of hepatic bile is alkaline (pH 7.5 - 8.0)

3. The stomach is a sharply acidic environment (at the height of digestion pH 1.8 - 3.0)

4. Pancreas - slightly alkaline pancreatic juice

5. Small intestine - alkaline reaction

6. Large intestine - slightly acidic reaction

Table 1. Hydrogen indicators for solutions

Solution	RN
Cl	1,0
H2SO4	1,2
H2C2O4	1,3
NaHSO4	1,4
N 3 PO 4	1,5
Gastric juice	1,6
Wine acid	2,0
Lemon acid	2,1
HNO2	2,2
Lemon juice	2,3
Lactic acid	2,4
Salicylic acid	2,4
Table vinegar	3,0
Grapefruit juice	3,2
CO 2	3,7
Apple juice	3,8
H2S	4,1
Urine	4,8-7,5
Black coffee	5,0
Saliva	7,4-8
Milk	6,7
Blood	7,35-7,45
Bile	7,8-8,6
Ocean water	7,9-8,4
Fe(OH)2	9,5
MgO	10,0
Mg(OH)2	10,5
Na 2 CO 3	11
Ca(OH)2	11,5
NaOH	13,0

The table allows us to make a number of interesting observations. pH values, for example, immediately indicate the relative strength of acids and bases. A strong change in the neutral environment as a result of the hydrolysis of salts formed by weak acids and bases, as well as during the dissociation of acidic salts, is also clearly visible.

Fish eggs and fry are especially sensitive to changes in pH.

Buffer solutions.

Maintaining the desired pH value and preventing it from noticeably deviating in one direction or another when conditions change is possible by using so-called buffer (from the English buff - to soften shocks) solutions. Such solutions are often a mixture of a weak acid and its salt or a weak base and its salt. Such solutions “resist”, within certain limits (called buffer capacity), attempts to change their pH. For example, if you try to slightly acidify a mixture of acetic acid and sodium acetate, then acetate ions will bind excess H + ions into slightly dissociated acetic acid, and the pH of the solution will hardly change (there are a lot of acetate ions in the buffer solution, since they are formed as a result of complete dissociation sodium acetate). On the other hand, if you introduce a little alkali into such a solution, the excess OH - ions will be neutralized by acetic acid while maintaining the pH value. Other buffer solutions act in a similar way, each of them maintaining a specific pH value. Solutions of acid salts of phosphoric acid and weak organic acids - oxalic, tartaric, citric, phthalic, etc. also have a buffering effect. The specific pH value of the buffer solution depends on the concentration of the buffer components. Thus, the acetate buffer allows you to maintain the pH of the solution in the range of 3.8-6.3; phosphate (a mixture of KH 2 PO 4 and Na 2 HPO 4) - in the range of 4.8 - 7.0, borate (a mixture of Na 2 B 4 O 7 and NaOH) - in the range of 9.2-11, etc.

Many natural liquids have buffering properties. An example is ocean water, the buffering properties of which are largely due to dissolved carbon dioxide and bicarbonate ions HCO 3 -. The source of the latter, in addition to CO 2, are huge amounts of calcium carbonate in the form of shells, chalk and limestone sediments in the ocean. Interestingly, the photosynthetic activity of plankton, one of the main suppliers of oxygen to the atmosphere, leads to an increase in the pH of the environment. This happens in accordance with Le Chatelier’s principle, as a result of a shift in equilibrium when absorbing dissolved carbon dioxide: 2H + +CO 3 2- = H + + HCO 3 -, H 2 CO 3 = H 2 O + CO 2. When CO 2 + H 2 O + hv = 1/n(CH 2 O) n + O 2 is removed from the solution during photosynthesis, the equilibrium shifts to the right and the environment becomes more alkaline. In the cells of the body, the hydration of CO 2 is catalyzed by the enzyme carbonic anhydrase.

Cellular fluid and blood are also examples of natural buffer solutions. Thus, blood contains about 0.025 mol/l of carbon dioxide, and its content in men is approximately 5% higher than in women. The concentration of bicarbonate ions in the blood is approximately the same (there are also more of them in men).

When testing soil, pH is one of the most important characteristics. Different soils can have a pH from 4.5 to 10. The pH value, in particular, can be used to judge the nutrient content of the soil, as well as which plants can grow successfully in a given soil. For example, the growth of beans, lettuce, and black currants is hampered when the soil pH is below 6.0; cabbage - below 5.4; apple trees - below 5.0; potatoes - below 4.9. Acidic soils are generally less nutrient rich because they are less able to retain the metal cations needed by plants. For example, hydrogen ions entering the soil displace bound Ca 2+ ions from it. And aluminum ions displaced from clayey (aluminosilicate) rocks in high concentrations are toxic to agricultural crops.

To deoxidize acidic soils, liming is used - adding substances that gradually bind excess acid. Such a substance can be natural minerals - chalk, limestone, dolomite, as well as lime, slag from metallurgical plants. The amount of deoxidizer applied depends on the buffer capacity of the soil. For example, liming clay soil requires more deoxidizing substances than sandy soil.

Of great importance are measurements of the pH of rainwater, which can be quite acidic due to the presence of sulfuric and nitric acids in it. These acids are formed in the atmosphere from nitrogen and sulfur (IV) oxides, which are emitted with waste from numerous industries, transport, boiler houses and thermal power plants. It is known that acid rain with a low pH value (less than 5.6) destroys vegetation and the living world of water bodies. Therefore, the pH of rainwater is constantly monitored.

Leather

For different skin types, the pH is quite different: from 3.5 (acidic) for dry skin, 5.5 for normal, to 6 (alkaline) for oily skin. In addition, there is a combination skin type, when the skin type is different in different areas of the skin. Therefore, the correct selection of cosmetics specifically for your skin type is very important.

Urine

It is very important to pay attention in time to changes in the pH level of the internal environment of the body and, if necessary, take urgent measures. Using pH test strips, you can easily, quickly and accurately determine your pH level without leaving your home. If the urine pH level fluctuates between 6.0 - 6.4 in the morning and 6.4 - 7.0 in the evening, then your body is functioning normally.

Urine pH value

Urine pH test results show how well the body absorbs minerals such as calcium, sodium, potassium and magnesium. These minerals are called "acid dampers" because they regulate the level of acidity in the body.

If the acidity is too high, the body does not produce acid. It should neutralize the acid. To do this, the body begins to borrow minerals from various organs, bones, etc. in order to neutralize excess acid that begins to accumulate in tissues. Thus, the acidity level is regulated.

Saliva

If the pH level in your saliva remains between 6.4 - 6.8 throughout the day, this also indicates the health of your body.

Saliva pH value

It is also rational to know the pH level of saliva. Test results show the activity of enzymes in the digestive tract, especially the liver and stomach. This indicator gives an idea of ​​​​the work of both the entire organism as a whole and its individual systems. Some people may have increased acidity in both urine and saliva - in which case we are dealing with "double acidity".

Blood Blood pH value

Blood pH is one of the most stringent physiological constants in the body. Normally, this indicator can vary between 7.36 - 7.42. A shift in this indicator by even 0.1 can lead to severe pathology. When the blood pH shifts by 0.2, a coma develops, and by 0.3, the person dies.

After performing submaximal power work in highly qualified athletes, the blood pH can drop to 7.0, that is, the blood turns from slightly alkaline to neutral (!).

If such blood is transfused into a healthy, untrained person, it will cause his death. The body of athletes is trained to withstand this degree of blood acidification, and even perform intense work in these conditions.

Some authors have obtained data on a decrease in blood pH in highly qualified athletes to 6.9 and even lower, that is, the blood reaction instead of alkaline becomes acidic (!). True, there is a great deal of mistrust in these data, and they are not always presented in textbooks. If such blood is administered to a healthy, untrained person, it will inevitably cause protein denaturation and, as a result, the death of the body.

One of the important reasons that allows athletes to withstand a high degree of blood acidification is the appearance of modified proteins (isomers of regular proteins) that have slightly different physicochemical properties. In particular, these protein isomers are not destroyed under conditions of decreasing pH.

A decrease in blood pH changes the properties of proteins and threatens their destruction. That is why the human body has powerful mechanisms to maintain blood pH at a strictly defined level. These mechanisms are called blood buffer systems.

However, the rate of acid formation when working at submaximal power is so high that the blood buffer systems do not have time to neutralize acidification. Therefore, blood acidification occurs, and this acidification is very high.

In high-class athletes (masters of sports and above), blood acidification, which occurs as a result of performing submaximal power work at important competitions, may be incompatible with life. The body of non-athletes or junior and intermediate athletes is not able to withstand work that leads to death as a result of blood acidification.

Bones

In 1968, an article appeared in The Lancet claiming that people who ate a diet that produced too much acid were putting their bones at risk. The fact is that the body usually maintains an acidity level of about 7.4. The kidneys get rid of excess acid by removing it in the urine, when the pH decreases to 7.38, the body extracts carbonates, phosphates and ammonium from bones and muscles to neutralize excess acid. Thus, bones not only provide a framework that prevents us from spreading out like a jellyfish, but they are also a kind of storehouse of minerals that neutralize acid. Two Harvard professors have calculated that a diet that is so acidic that it requires 60 milliliters of bicarbonate from the skeleton every day will lose 15% of our bone mass in ten years!

Over the course of 7 years, a study was conducted at the University of California (San Francisco), where 9 thousand women were examined.

The results showed that with constant elevated levels of acidity, bones become brittle. The specialists who conducted this experiment are confident that most of the problems of middle-aged women are associated with excessive consumption of meat and lack of consumption of vegetable foods. Therefore, the body has no choice but to take calcium from its own bones and use it to regulate the pH level. (American Journal of Clinical Nutrition).

Leather

It is generally accepted that cosmetic preparations must have a certain acidity, characterized by a pH value from 5.0 to 6.0. What facts force cosmetologists from generation to generation, from one manual to another, to repeat the “truism” that cosmetic preparations must be acidic in nature?

The only argument in favor of this statement is the fact that the upper layer of the epidermis (keratin scales) is acidic with a pH value of 5.0 to 6.0. Indeed, during the process of keratinization, the cell formed in the lower (basal) layer of the epidermis gradually moves to the upper layers of the skin. Losing connection with the nutrients of the blood plasma and the ability to divide, simultaneously under the influence of atmospheric oxygen, any type of radiation, environmental effects of heavy metal ions and turns into keratin scales, the structure of which determines its acidic nature. There is also information that the acidity of the skin surface can be determined by the acidic nature of the secretion of the sebaceous glands. However, these considerations concern (and rightly so) only the outer layer of the epidermis. In turn, the deeper the cell is located, the more similar it is to the original full-fledged cell capable of division. But for such cells the dependence is different. For dividing cells, it is known that the optimal pH value can vary from 6.7 to 7.3, that is, the average pH value is 7.0 +/- 0.3.

Genitals

The pH of cervical mucus is assessed using a special test strip immediately after collection or directly in the cervical canal. Normal pH is 6.4-8.0. Changes in the pH of cervical mucus have a great influence on sperm motility. An acidic environment makes sperm immobile, while an alkaline environment increases their motility. The optimal pH of 7.0-8.0 is observed in the periovulatory period of the menstrual cycle. A significant decrease in the pH of cervical mucus is often associated with bacterial infections.

Most of the ejaculate is sperm. Its normal volume per ejaculation is from 2 to 6 ml. Normal semen has a yellowish or fawn color and a pungent odor (all strong or unpleasant odors are not normal). At human body temperature, sperm liquefies within an hour. Its acidity ranges from 7.2 to 8.

Gastric juice

Biological catalysts - enzymes are able to work only within certain pH limits, and when they go beyond these limits, their activity can sharply decrease. For example, the activity of the enzyme pepsin, which catalyzes the hydrolysis of proteins and thus promotes the digestion of protein foods in the stomach, is maximum at pH values ​​of about 2. Therefore, for normal digestion it is necessary that gastric juice have fairly low pH values: normally 1.53 -1.67. With a gastric ulcer, the pH drops to an average of 1.48, and with a duodenal ulcer it can even reach 1.05. The exact pH value of gastric juice is determined by intragastric examination (pH probe). If a person has low acidity, the doctor may prescribe taking a weak solution of hydrochloric acid with food, and if there is increased acidity, take antacid agents, for example, magnesium or aluminum hydroxides. Interestingly, if you drink lemon juice, the acidity of gastric juice... will decrease! Indeed, a solution of citric acid will only dilute the stronger hydrochloric acid contained in gastric juice.

Cells and intercellular fluid

In the cells of the body the pH is about 7, in the extracellular fluid it is 7.4. Nerve endings that are outside cells are very sensitive to changes in pH. When mechanical or thermal damage occurs to tissues, cell walls are destroyed and their contents reach the nerve endings. As a result, the person feels pain. Scandinavian researcher Olaf Lindahl conducted the following experiment: using a special needle-free injector, a very thin stream of solution was injected through the skin of a person, which did not damage the cells, but acted on the nerve endings. It has been shown that it is hydrogen cations that cause pain, and as the pH of the solution decreases, the pain intensifies. Similarly, a solution of formic acid, which is injected under the skin by stinging insects or nettles, directly “acts on the nerves.” The different pH values ​​of tissues also explain why with some inflammations a person feels pain, and with others - not.

Interestingly, injecting clean water under the skin produced particularly severe pain. This phenomenon, strange at first glance, is explained as follows: when cells come into contact with clean water as a result of osmotic pressure, they rupture, and their contents affect the nerve endings.

Intestines

The intestinal parietal microflora prevents the permeability of pathogenic microbes through the mucous membrane. Its antibacterial activity is created through the synthesis of organic acids, as a result of which the acidity (pH) of the environment drops to 4.0-3.8. Such low acidity inhibits the growth and reproduction of pathogenic and putrefactive microorganisms, which thrive in the alkaline environment that occurs during rotting and fermentation in the intestinal tract.

Diseases

Ignorance of your pH level can lead to dire consequences.

A) Increased acidity in the body.

An imbalance in the pH of the body in most people manifests itself in the form of increased acidity (a state of acidosis). In this condition, the body poorly absorbs minerals such as calcium, sodium, potassium and magnesium, which, due to excess acidity, are excreted from the body. Vital organs suffer from a lack of minerals.

If acidosis is not detected in time, it can harm the body unnoticed, but constantly for several months and even years. Alcohol abuse often leads to acidosis. Acidosis can occur as a complication of diabetes.

At Acidosis may cause the following problems:

· Diseases of the cardiovascular system, including persistent vasospasm and decreased oxygen concentration in the blood.

· Weight gain and diabetes.

· Kidney and bladder diseases, stone formation.

· Decreased immunity.

· Increased harmful effects of free radicals, which can contribute to tumorigenesis.

· Bone fragility up to a hip fracture, as well as other disorders of the musculoskeletal system, such as the formation of osteophytes (spurs).

· The appearance of joint pain and pain in the muscles associated with the accumulation of lactic acid.

· General weakness.

B) Increased alkali content in the body.

With an increased content of alkali in the body, and this condition is called alkalosis, as well as with acidosis, the absorption of minerals is impaired. Food is digested much more slowly, which allows toxins to pass from the gastrointestinal tract into the blood. An increased level of alkali in the body is dangerous and difficult to correct. As a rule, it is the result of the use of drugs containing alkali.

An increased alkali content can provoke:

· Skin and liver problems.

· Strong and unpleasant odor from the mouth and body.

· Various allergic manifestations associated with food and environmental pollution.

· Exacerbation of chronic diseases.

· Constipation and other intestinal problems.

Fish can also suffer from this disease.

Acidosis occurs when fish are kept in acidic water. To prevent disease, it is necessary to monitor the pH readings of the water, not allowing the acidity (pH) to drop below 5.5.

When creating a collection of fish that live in soft, acidic waters, it is necessary to ensure that species that require neutral or slightly alkaline water do not enter the aquarium, since they may develop acidosis first. To protect fish from alkalosis, the pH value of the water should not exceed 8.5. Representatives of the suborder Characovidae are most susceptible to this disease in conditions where the pH is greater than 7.

The experience gained in diagnostics using the biolocation method has shown that in 90% of people with a latent hepatitis virus infection, the number of malignant cells in the blood and lymph was at or above the limit at which the body is able to cope with the growth of cancer cells. Thus, the hepatitis virus provokes cancer body.

The danger also lies in the fact that this virus is stable in the acidic environment created by the immune system in the blood, gastrointestinal tract, and on the mucous membrane of organs. This environment is destructive for many infections, but not for hepatitis viruses.

God created man as a unique automated system capable of changing its functions within certain limits. So, when the hepatitis virus enters, the body changes the acidic environment of the blood towards alkaline, i.e. it increases the pH of the blood, since for this virus the alkaline environment is more dangerous. However, it cannot make pH more than 7.47, because this is its programmed limit (human blood pH is in the range of 7.15 - 7.47). And a direct consequence of a shift in blood pH towards an alkaline environment is the initiation of other infections!.. This is how a state of immunodeficiency results, in which the body can die from pneumonia, influenza and other diseases that it would have successfully dealt with with normal blood pH. That is why the hepatitis virus can be considered one of the main components of the so-called HIV infection.

Some drinks with a low pH increase the symptoms of the reflex in esophagitis. These drinks include Coca-Cola and Pepsi-Cola (pH=2.5), red wine (pH=3.25) and orange juice (pH=3.5).

Reducing the frequency and intensity of contact with acid. Obviously, the optimal preventive measure would be to eliminate the source of the acid or prevent it from coming into contact with the teeth.

If erosion of “dietary” (food) etiology, it is necessary to reduce the frequency of consumption of acidic foods and exclude them from main meals. Research conducted by Amaechi B. T. at al. showed that the degree of erosion of tooth tissue is directly dependent on the time of contact of teeth with acid, therefore acid-containing drinks, such as juices and carbonated drinks, should be drunk quickly, rather than sipped slowly, or drunk through straw. Vitamins should be taken orally in capsule form.

It is known that the pH of fruit juices and carbonated drinks is very low, which contributes to the spread of erosions. The consumption of these drinks has increased significantly in recent years, so it is necessary to educate patients about the potential of these drinks to cause dental erosion. When comparing the erosive potential of different drinks, their buffering activity was arranged in the following order: natural fruit juice - fruit-based carbonated drink - non-fruit-based carbonated drinks - sparkling mineral waters - natural mineral waters. Among natural juices, blackcurrant juice has the greatest erosive potential, and apple juice has the least. Thus, it is necessary to recommend that patients, when choosing drinks, give preference to natural non-carbonated mineral waters.

A promising direction in the prevention of erosion is the creation of drinks with low erosive potential. Because Erosion is a consequence of an acid attack on a tooth. Obviously, one of the ways of prevention is to reduce the acid content in drinks that cause erosion. However, this increases the difficulty of creating a recipe, because The taste of the drink depends on its acidity. Soft drinks can contain acids in 2 different forms: a) fruit acids and acids responsible for taste and b) carboxylic acids to create gases.

A) Fruit juices vary in acidity levels, and therefore it is possible to increase the content of potentially low-erosive acids at the expense of more erosive ones. For example, a study conducted by Meurman at al. showed that citric acid is more erosive than maleic and phosphoric acid. Based on these data, maleic acid is a better choice for beverage production than citric or phosphoric acid.

B) Carbonated drinks have a lower pH and higher titratable acidity. In experiments, carbonated drinks lead to a higher degree of enamel erosion compared to non-carbonated drinks, and dentin damage occurs even more than when teeth come into contact with orange juice. Consequently, the erosiveness of the drink can be reduced by reducing the degree of carbonation.

Smoking. The absorption of nicotine into the body depends on the pH levels at the time of intake. Absorption of nicotine from acidic cigarette smoke occurs in the lungs. Alkaline smoke from pipe tobacco and cigars allows nicotine to be absorbed through the mucous membrane in the mouth.

It is a common misconception that the main problem for humans is increased stomach acidity. It causes heartburn and ulcers. In fact, a much bigger problem is low stomach acidity, which occurs many times more often.

Lack of hydrochloric acid creates ideal conditions for colonization of the intestinal tract various bacteria, protozoa and worms. The insidiousness of the situation is that low stomach acidity “behaves quietly” and goes unnoticed by humans.

Here is a list of signs that suggest a decrease in stomach acidity.

· Discomfort in the stomach after eating.

· Nausea after taking medications.

· Flatulence in the small intestine.

· Loose stools or constipation.

· Undigested food particles in the stool.

· Itching around the anus.

· Multiple food allergies.

· Dysbacteriosis or candidiasis.

· Dilated blood vessels on the cheeks and nose.

· Acne.

· Weak, peeling nails.

· Anemia due to poor absorption of iron.

Of course, an accurate diagnosis of low acidity requires determining the pH of gastric juice (for this you need to contact a gastroenterologist).

When acidity is high, there are many drugs to reduce it.

In the case of low acidity, there are very few effective remedies. As a rule, hydrochloric acid preparations or vegetable bitters are used that stimulate the secretion of gastric juice (wormwood, calamus, peppermint, fennel, etc.).

Cosmetic products.

Researcher at the Institute of Immunology of the Siberian Branch of the Russian Academy of Medical Sciences E.A. Vyazova conducted special experiments on maintaining and growing cells in media with different pH values. The results show that when exposed to pH=5.5 for 8 hours, more than 30 cells died. If you bring the pH to 4.5, then more than 90 cells die. Approximately the same picture is observed when the pH changes to the alkaline side.

Thus, increased acidity and increased alkalinity of the environment interacting with living cells is an unfavorable factor. The lower (basal) cells of the epidermis are washed by blood plasma, the pH value of which is 7.2 +/- 0.1 and which has a certain buffer capacity. The buffering capacity of blood plasma is the reason that you and I, dear reader, have not yet “sloughed off” using cosmetic compositions of an acidic nature with a pH value of 5.5. We are, figuratively speaking, alive thanks to the implementation of a protective mechanism associated with the buffer capacity of the blood plasma, which ensures that the pH value is maintained at an optimal level even when exposed to fairly strong acidic or alkaline agents.

Now, let's try to answer a simple question. If the optimal pH value for the existence of cellular systems in the body and outside it is 7.2 +/- 0.3, then what is the need to constantly “load” the cellular system with acidic cosmetic preparations with pH = 5.5? And how long can this continue?

This can hardly be justified by the fact that the thin scaly keratin layer has a similar acidity. After all, when we are dealing with nourishing, vitaminizing or regenerating creams and masks, it is assumed that their active substances should penetrate into the deep layers of the skin and have a beneficial effect on living cellular systems. And what kind of “favor” is this - an acidified creamy composition?

Products

Our hunting ancestors ate a lot of meat, but their acid load was balanced by carbohydrates from fruits and vegetables. Today, bread and pasta - the mainstay of the Western diet - produce a lot of acid because they contain a lot of phosphorus, which the body converts into phosphoric acid. Over the past 40 years, our consumption of protein, which turns into acid, has increased by 50%. And if we do not neutralize the meat with base-producing greens, then we cannot be helped by the protein from our own tissues.

But the greatest threat to our bones comes from hard cheeses: loaded with calcium and therefore recommended for protecting bones, they are the main source of acid in the body and the main culprit of “corrosion” of bones! Note that milk is not yet suspect because it contains approximately the same amount of ingredients that turn into acids and bases, and the process of making hard cheeses removes the components that turn into bases in the body along with the liquid.

Natural water always has an acidic reaction (pH< 7) из-за того, что в ней растворен углекислый газ; при его реакции с водой образуется кислота: СО 2 + Н 2 О = Н + + НСО 3 2- . Если насытить воду углекислым газом при атмосферном давлении, рН полученной «газировки» будет равен 3,7; такую кислотность имеет примерно 0,0007%-ный раствор соляной кислоты - желудочный сок намного кислее! Но даже если повысить давление CO 2 над раствором до 20 атм., значение pH не опускается ниже 3,3. Это значит, что газированную воду (в умеренных количествах, конечно) можно пить без вреда для здоровья, даже если она насыщена углекислым газом.

Canning. Various microorganisms are also very sensitive to the acidity of the environment. Thus, pathogenic microbes develop quickly in a slightly alkaline environment, whereas they cannot withstand an acidic environment. Therefore, for preserving (pickling, salting) products, as a rule, acidic solutions are used, adding vinegar or food acids to them.

Water. Typically, the pH level is within the range at which it does not directly affect the consumer quality of water. Thus, in river waters the pH is usually in the range of 6.5-8.5, in precipitation 4.6-6.1, in swamps 5.5-6.0, in sea waters 7.9-8.3. Therefore, WHO does not propose any medically recommended value for pH. At the same time, it is known that at low pH water is highly corrosive, and at high levels (pH>11), water acquires a characteristic soapiness, an unpleasant odor, and can cause irritation to the eyes and skin. That is why the optimal pH level for drinking and domestic water is considered to be in the range from 6 to 9.

Consumption of large quantities animal fats, sweets, alcohol, coffee and nicotine, and frequent stress leads to disruption of this balance, namely, they “over-oxidize” the body. Acid metabolic products are not completely removed from tissues, but are retained in the intercellular fluid in the form of salts, provoking the development of many diseases. By the way, the notorious cellulite is also a consequence of a violation of the acid-base balance of the body. Proper nutrition and special cleansing procedures will help correct the balance, and therefore protect yourself from illnesses.
These foods restore the acid-base balance, so they should be included more often in the diet:
- stand salads;

Sprouted cereals;
- almost all types of vegetables;
- potato;
- dried fruits;
- nuts, almonds;
- water without gas.

TO potatoes form an excess of alkali in the body, which makes it an indispensable product for “overoxidation”. Alkaline drinks (such as whey, green tea, alkaline mineral water) are also very beneficial.
These foods should not be included in the menu too often, as they “over-oxidize” the body:
- meat and fish;
- products made from white flour;
- coffee, black tea;
- lemonade containing sugar;
- confectionery products.

By the way, not everything that tastes sour turns into acid in the body! For example, when a sour apple is digested, mainly alkaline compounds are formed!
How to determine excess acid in the body? For this purpose, pharmacies sell special strips that determine the acid-base level of urine. A number below 7 indicates that you have excess acid in your body. A score above 7 indicates that you are doing well. The measurement procedure is carried out in the morning after sleep and then several times during the day. This allows you to track the trend of the acid-base state of your body.

The effect of coffee on the gastrointestinal tract is extremely effective. Here the exciting, stimulating effect of not only caffeine, but also acids, aromatic and flavoring substances formed during the coffee roasting process is fully manifested. Gastric secretion caused by coffee is equivalent to the action of the universally recognized activator of the secretory reaction - meat broth. 20-30 minutes after drinking black coffee, the acidity in the stomach reaches its maximum. With an increase in the concentration of the drink in the gastric contents, the content of free hydrochloric acid increases, the total acidity increases, which accelerates the digestion and evacuation of food from the stomach.
Coffee, by increasing the secretion of gastric juice, helps to increase the digestibility of food. It is not for nothing that many peoples traditionally serve black coffee after breakfast and lunch.
Black coffee, as a strong stimulant of gastric secretion, should be excluded from the diet of patients with peptic ulcers and hyperacid gastritis. Coffee lovers with these diseases can be recommended to drink coffee with milk, cream and sugar, since the stimulating effect of coffee on gastric secretion is significantly reduced.
Almost everything vegetable juices have the properties to correct the acid-base balance of the blood, disturbed during tiring work. This is due to the predominance of alkaline residues in them. Juices increase the activity of enzymes and metabolism, ensure the neutralization of “fatigue toxins” and their removal from the body. Vegetable juices contain less organic acids, which is why they taste blander, but are richer in minerals (such as potassium, sodium, calcium, iron, etc.). In addition, it is vegetable juices that very effectively restore our body in crisis situations. Fruits tend to be higher in calories because they contain more sugar, but they are also great for cleansing our bodies.

The only thing in which canned juices are not inferior to fresh juices is their mineral content. Therefore, when buying canned juice, you should pay attention to the name of the drink. If the word “drink” is written on it, then the content of the juice itself does not exceed 10-15 percent, the rest is water, citric ascorbic acid, as well as various dyes and preservatives.
The “nectar” contains 50 percent juice, and the rest is the above ingredients. There are also inscriptions on the packaging stating “100 percent juice.” However, one should not be deluded here either, because such juice is also prepared from a concentrated product with the addition of water and sugar, which in no way indicates that it is one hundred percent.”

As can be seen from the article, you can help the body adjust pH in different ways, but one of the most effective is the use of Living and Dead water.

When it is better to use it is clear from the article.

From the book: Randy Holmes-Farley: Reef Alchemy

The pH value in a reef aquarium greatly affects the vitality and condition of the organisms that call the aquarium their home. Unfortunately, there are many factors that push pH beyond the optimal range for many organisms kept together in saltwater aquariums. For example, a pH value that is too low makes it difficult for calcifying organisms to form calcium carbonate skeletons. At a low enough pH, ​​these skeletons actually begin to dissolve. For this reason, aquarists should monitor this parameter. Such an observation is often the first step towards solving various pH-related issues. Many reef aquarists rank low pH as one of the most annoying problems associated with maintaining suitable aquarium conditions. This article will take a closer look at the reasons that can lead to low pH values ​​in many aquariums and outline the best ways to increase it. The problems associated with high pH were briefly discussed in my previous article.

What is pH?

This chapter should help aquarists understand what the term “pH” means. Those who only want to solve the problem of low pH can skip directly to the bold text at the end of this section.

There are many different definitions of pH as applied to seawater. In the system used by most aquarists (National Bureau of Standards - NBS) pH is determined according to equation 1:

1. pH = -log a H

where a H is the "activity" of hydrogen ions (H+, also called protons) in solution. Activity is the way chemists measure “free” concentrations, and pH is a measure of the number of hydrogen ions in a solution. Hydrogen ions in sea water are partly in a free state (in fact, they are not free, but join water molecules, forming complexes - for example, H 3 O + ), and some are complexed with other ions (which is why chemists use the term “activity” instead of concentration). In particular, H+ ions in ordinary seawater are present as free H+ ions (about 73% of the total), as H+ /SO4 - ion pairs (about 25% of the total H+ content), and as pairs H + /F - ions (a small fraction of the total H +). Potency issues also affect calibration buffers, and this is one reason why different pH scales and calibration buffers are used for seawater. For us aquarists, however, all these other standards have little relevance: in the aquarium hobby, it is customary to deal exclusively with the standard NBS (US National Bureau of Standards) system.

To understand the main problems associated with the pH value in saltwater aquariums, we can think of the pH value as being directly related to the H+ concentration:

2. pH = - gH log

Where gH– constant (activity coefficient), which, in most cases, can be ignored ( gH= 1 in pure fresh water and ~0.72 in sea water). Essentially, all aquarists need to understand is that pH is a measure of the number of hydrogen ions in a solution, and that the pH scale is logarithmic. This means that at pH 6 there are 10 times more ions H+ than at pH 7, and that at pH 6 there are 100 times more H+ ions than at pH 8. Therefore, a small change in pH can be associated with a large change in concentrationH+ ions in water.

Why control pH?

There are several reasons why aquarists would like to control the pH in saltwater aquariums. One of them is that aquatic organisms grow actively only in a certain pH range. Naturally, this range varies from organism to organism, and the concept of an "optimal" range may not be entirely correct for an aquarium containing many different species. Even natural seawater (pH = 8.0-8.3) will not be optimal for all creatures living in it. However, more than eighty years ago it was recognized that pH values ​​that differ greatly from those found in natural seawater (eg below pH 7.3) are a source of stress for fish 1 . We now have more information about the optimal pH ranges for many organisms, but unfortunately this data is not sufficient to enable aquarists to find the optimal pH for most of the organisms in which they are interested. 2-6 In addition, pH effects can be indirect. For example, it is known that the toxicity of copper and nickel to some organisms present in our aquariums (such as mysids and heteropods) depends on the pH 7 value. As a result, the pH ranges that will be acceptable in one aquarium may differ from those that are acceptable in another, even if the same organisms live in those aquariums.

However, there are fundamental processes occurring in many marine organisms that are severely affected by changes in pH. One of them is calcification (hardening). Calcification in corals is known to be pH dependent and decreases as the pH drops. 8-9 Using such factors, coupled with the experience gained by many hobbyists, we can develop some guidelines regarding acceptable pH ranges and maximum values ​​for reef aquariums.

What is the acceptable pH range for a reef aquarium?

The acceptable pH range for reef aquariums is an opinion rather than a concrete fact, and will naturally vary depending on who is giving the opinion. And this range can be quite different from the “optimal” range. However, compared to the acceptable range, it is much more difficult to justify what the “optimal range” is. I suggest that a natural seawater pH of around 8.2 is appropriate, but a reef aquarium can live in a wider range of pH values. I believe that a pH range of 7.8 to 8.5 is acceptable for reef aquariums, with some allowances, as follows:

• The buffering capacity (KH) should be at least 2.5 mEq/L, and preferably higher, especially towards the lower end of the pH range. This point is based in part on the fact that many reef aquariums are kept quite effectively in the pH range of 7.8-8.0. However, most of the best of these aquariums contain a calcium reactor, which, although it tends to lower the pH, still maintains a fairly high KH level (3 mEq/L and above). In this case, any problems associated with calcination at low pH values ​​can be compensated for by increasing alkalinity. Low pH primarily affects calcifying organisms, making it difficult to obtain enough carbonate to form skeletons. Increasing buffering mitigates this problem for reasons that will be discussed in detail later in this article.
• Calcium levels should be at least 400 ppm. As the pH decreases, calcification becomes more difficult; it also becomes more difficult as calcium levels decrease. It is highly undesirable to simultaneously have extremely low values ​​of pH, alkalinity and calcium content. Thus, if the pH is in the low range and cannot easily be changed (such as in an aquarium with a CaCO3/CO2 calcium reactor), you should at least provide an acceptable calcium level (~400-450 ppm). Moreover, one of the problems that arises at high pH values ​​(above 8.2) is abiotic precipitation of calcium carbonate, leading to a drop in calcium and alkalinity and clogging of heaters and pump impellers. If the aquarium pH is 8.4 or higher (as is often the case in aquariums using Ca(OH)2 lime water - kalkwasser), due care must be taken to maintain proper calcium levels and buffering. This means that these levels should be neither too low to cause biological calcification nor too high to cause excessive abiotic deposition on the equipment.

Carbon dioxide and pH

The pH value in a saltwater aquarium is closely related to the amount of carbon dioxide dissolved in the water. It is also associated with buffering. Indeed, if the water is completely aerated (that is, in complete equilibrium with ordinary air), then the pH value is precisely determined by the alkalinity of the carbonate. The higher the alkalinity, the higher the pH. Figure 1 shows the relationship for seawater in equilibrium with normal air (350 ppm carbon dioxide) and water in equilibrium with air containing excess carbon dioxide that may be present in the home (1000 ppm). It is obvious that with any buffering, with an increase in the carbon dioxide content, the pH value will decrease. Excess carbon dioxide is what causes low pH in reef aquariums.

Figure 1. Relationship between buffering capacity and pH in seawater in equilibrium with air containing normal and elevated amounts of carbon dioxide.

The green dot represents natural seawater in equilibrium with normal air, and the curves represent the result that would be obtained with increased or decreased buffering.

Simplified, this relationship can be understood as follows: Carbon dioxide is present in the air in the form of CO 2. When dissolved in water, it turns into carbonic acid H 2 CO 3:

3. CO 2 + H 2 O -> H 2 CO 3

The amount of H 2 CO 3 in water (when it is well aerated) does not depend on pH, but only on the carbon dioxide content of the air (and, to some extent, on other factors such as temperature and salinity). In non-air balanced systems, which include many reef aquariums, these aquariums can be considered "as if" they were in equilibrium with a certain amount of CO 2 in the air, which is effectively determined by the amount of H 2 CO 3 in the water. Therefore, if there is "excess CO2" in the aquarium (or the air with which it is equilibrated), this means that there is excess H2CO3 present in the aquarium, which in turn means that the pH value should drop like this shown below.

Sea water contains a mixture of carbonic acid, bicarbonate and carbonate, which are always in equilibrium:

4. H 2 CO 3 -> H + + HCO 3 - -> 2H + + CO 3 --

Equation 4 shows that if there is an excess of H 2 CO 3 in the aquarium, some of it dissociates (breaks into pieces), turning into H + , HCO 3 - and CO 3 - ions. As a result of excess H +, the pH value will be lower than if it had less CO 2 /H 2 CO 3. If there is a large excess of CO 2 in seawater, the pH value can drop to very low values ​​(pH 4-6). Equilibrating the water in my aquarium with carbon dioxide at 1 atmosphere of pressure resulted in a pH drop to 5.0, although it is unlikely that such a low value would be achieved in a reef aquarium since the soil and coral carcasses therein would act as a buffer to the dissolution. In my aquarium, water equilibrated with carbon dioxide at 1 atmosphere of pressure, in the presence of excess solid aragonite (a crystalline form of calcium carbonate, i.e. the same form found in coral carcasses), resulted in a pH value of 5.8.

If the buffering capacity is 3 mEq/L (8.4 dKH) and the pH is 7.93, this means that there is excess CO 2 in the aquarium (otherwise the pH value should be slightly higher than 8.3).

Figures 2-5 graphically show some ways to increase pH in aquariums. Ways to increase pH include:

• Saturating the water with "regular air", displacing excess carbon dioxide, will shift the aquarium's characteristics along the green line (Figure 3), causing the pH value to rise slightly above pH 8.3. The same result would occur if the excess carbon dioxide was absorbed as a result of the growth of macro algae. However, it rarely happens that such a phenomenon could lead to a shift of the characteristic along the green line, to a value above pH 8.3.
• Increasing Buffer: Even if the aquarium continues to have excess CO2, increasing buffering will cause the pH along the green line (Figure 4) to increase to 8.1 for a buffer of 4.5 mEq/L (12.6 dKH).
• The use of lime water (kalkwasser) to reduce excess CO 2 to normal levels, as well as to increase buffering (up to 4 mEq/L), can lead to a shift of the curve along the green line (Figure 5), which will lead to an increase in pH above 8.4 and buffer capacity up to 4 meq/l (11.2 dKH).

Figure 2. Same curves as in Figure 1. The red lines show the pH value,

which is obtained with a buffer capacity of 3 meq/l (8.4 dKH). It is clearly visible that the pH value is significantly higher

at normal levels of carbon dioxide than at elevated levels.

Figure 3. The same curves illustrating the effect of aeration on pH,

with excess initial carbon dioxide content

Figure 4. The same curves illustrating the effect of increasing buffering on pH,

while maintaining a high carbon dioxide content

Figure 5. The same curves illustrating the effect of lime water (kalkwasser) on pH by reducing excess carbon dioxide (hydroxide reacts with carbon dioxide to form
bicarbonate and carbonate), simultaneously with an increase in buffering capacity.

Why does the pH value change between daytime and nighttime?

Daily pH changes in reef aquariums occur due to the biological processes of photosynthesis and respiration. Photosytnesis is the process by which organisms convert carbon dioxide and water into carbohydrates and oxygen:

5. 6CO 2 + 6H 2 O + light -> C 6 H 12 O 6 (carbohydrates) + 6O 2

Thus, carbon dioxide is consumed during the daytime. As a result of this consumption, many aquariums become CO2-starved during the daytime and the pH rises.

In addition, the organisms living in the aquarium also carry out the process of respiration, during which carbohydrates are converted back into energy, which will be used for other purposes. In essence, this process is the opposite of photosynthesis:

6. C 6 H 12 O 6 (carbohydrates) + 6O 2 -> 6CO 2 + 6H 2 O + energy

This process occurs constantly in a reef aquarium and causes the pH to drop due to the production of carbon dioxide.

As a result of the combined effect of these processes, in most reef aquariums the pH increases during the day and decreases at night. For a typical aquarium, this pH change ranges from less than 0.1 to more than 0.5. As discussed elsewhere in this article, active aeration of aquarium water to displace excess carbon dioxide or attract carbon dioxide when it is deficient completely eliminates daily pH fluctuations. In practice, however, it is difficult to achieve complete compensation; the pH value is different during the day and at night.

In addition to aeration, pH changes are affected by the presence of buffer solutions. High carbonate buffering results in less fluctuation in pH because the combination of carbonate and bicarbonate creates a buffer, moderating changes in pH. Boric acid and its salts also form a buffer that mitigates pH changes. The capacity of both of these buffer systems is higher at high pH values ​​(8.5) than at low pH values ​​(7.8). Thus, aquarists whose aquarium pH is low may experience greater fluctuations in pH values ​​for this reason. I discussed buffering effects and the challenges of diurnal pH fluctuations in detail in a previous article.

Solving pH Problems

Below are specific tips for solving low pH problems. These tips can also help with adjusting pH levels closer to natural values, even if those levels are already within the "acceptable range" as described above, but still not as high as desired. However, before you begin implementing your pH strategy, here are some general guidelines:

Make sure you actually have a pH problem. Often, as a result of incorrect measurements, you may think there is a problem. This situation is most common when the aquarist uses a test kit (drop test or test strips) to measure pH rather than using an electronic pH meter. However, errors are possible with any measurement, and it would be a shame if you made your aquarium worse just because the pH meter was not calibrated correctly. Therefore, before starting corrective measures, make sure that the pH values ​​have been measured correctly. Below are links to two articles that are worth reading to ensure you are measuring pH correctly:

• Calibrating a pH meter using borax from a hardware store.

Before you start looking for a solution, try to determine the reason why the problem occurred. For example, if a low pH value is caused by excess carbon dioxide in the indoor air, increasing aeration with the same air is unlikely to help solve the problem. A much better solution would be if you address the very essence of the problem.

Causes of low pH

As described above, when the pH value drops below 7.8, problems arise. This means that during the day the lower pH value drops below 7.8. Of course, if the lower pH value drops to 7.9, it will still be necessary to raise the pH value, but it will not be as urgent. Typically, there are several reasons that can lead to a low pH value, and each case requires different actions. There is no universal way to protect an aquarium from all these problems at the same time!

The first step in solving the problem of low pH is to find out what causes it. Possible reasons could be the following:

1. The aquarium uses a calcium reactor (calcium carbonate reactor with carbon dioxide: CaCO 3 /CO 2 ).
2. The aquarium has low buffering capacity.
3. Due to insufficient aeration, there is more CO 2 in the aquarium than in the surrounding air. Don't be fooled into thinking that the aquarium will be sufficiently oxygenated because the water is very turbulent. It is MUCH more difficult to bring carbon dioxide levels into equilibrium than it is to simply provide enough oxygen. If carbon dioxide were in perfect equilibrium, there would be NO difference between daytime and nighttime pH values. Since most aquariums have a lower pH at night, this indicates that they are not fully aerated.
4. There is excess CO 2 in the aquarium because the indoor air contains excess CO 2 .
5. The aquarium is in the process of starting up and contains excess acid from the nitrogen cycle and the decomposition of organic matter into CO 2 .

Aeration test

Some of the options listed above require some effort to diagnose. Problems 3 and 4 are quite common, and there is an easy way to identify them. Take a glass of water from the aquarium and measure the pH. Then aerate this water vigorously for an hour using outside air. The pH value will increase if the pH was too low for the available buffer value, according to Figure 3 (if the pH rises, it is likely that one of the pH or buffer measurements was in error). In this case, repeat the experiment with a new glass of water, using room air for aeration. If the pH rises again, then the pH in the aquarium will also rise as a result of aeration, because the water in the aquarium contains an excess dose of carbon dioxide. If the pH in the glass does not rise (or rises very slowly), this means that the air in the room contains excess CO 2, and increasing the saturation with this air will not solve the problem of low pH (however, the problem can be solved if fresh water is used to saturate it). air).

Solving Low pH Problems

Some solutions are only suitable for certain reasons, and these are discussed in detail below. However, there are general solutions that are often effective. Such solutions include the use of additives to increase pH. They are used in cases where increased buffering capacity is required. In this case, it is best to use lime water (kalkwasser), after which two-component additives can be used to increase the pH. The advantage of these methods is that they increase the pH without disturbing the calcium balance.

Using buffer solutions alone is not always a good method, since they only slightly increase the pH value, while the buffering capacity increases significantly. Unfortunately, the labels on many commercially available buffer solutions are written to convince aquarists that the pH will be fine if they simply add some of the solution. In most cases, the improvement in pH occurs only for one day, while the alkalinity increases beyond the desired limits.

Two other useful methods are to grow macro algae, which absorb some CO2 from the water as they grow (often the algae is lit out of phase with the main aquarium - the light in the macroalgae tank is turned on at night when the lights in the main aquarium are off to minimize the decrease in pH ), and saturation of water with fresh air taken from outside the room.

Low pH value caused by calcium reactor

A common cause of low pH in a reef aquarium is the use of a calcium reactor. These reactors use carbon dioxide, which is acidic, to dissolve calcium carbonate, resulting in a significant amount of acid being released into the aquarium, albeit temporarily. Ideally, carbon dioxide should be ventilated from the reactor after some of it has been consumed to dissolve CaCO 3 . But in reality, this process is not complete, and aquariums that use a calcium reactor usually operate at pH values ​​close to the lower end of the acceptable range.

The proposed solutions assume that the reactor has been properly adjusted. A poorly set reactor can cause the pH to drop below normal, so the first step should be to set the pH accordingly. The issue of setting up a calcium reactor is beyond the scope of this article; we only note that the pH values ​​​​and buffering capacity of the water flowing from the reactor should not be too low.

To minimize the low pH problem resulting from the use of calcium reactors, many different approaches have been proposed, with varying degrees of success. One such approach is to use a two-chamber reactor, in which the effluent water passes through a second chamber containing CaCO 3 before being discharged into the aquarium. Dissolving additional CaCO 3 increases the pH and also causes an increase in calcium levels and buffering in the solution. This approach appears to be successful in raising the pH of the reactor effluent water, but not all the way to the aquarium, and the problem of low pH does not completely disappear.

Another approach is to aerate the water leaving the calcium reactor before it enters the aquarium. The purpose of this method is to blow out excess CO2 before water enters the aquarium. This approach is good in theory, but not in practice, since insufficient time is allowed for degassing before entering the aquarium. Another problem with this approach is the fact that if the pH is successfully raised, the solution may become supersaturated with CaCO 3 , which can lead to secondary precipitation of CaCO 3 in the reactor, thereby fouling it and reducing efficiency.

Finally, the final approach, perhaps the most successful, is to combine a calcium reactor with another buffering system that also increases the pH value. The most successful solution is probably to use lime water (calcium hydroxide). In this case, lime water is used not so much to increase dissolved calcium or increase buffering capacity, but to absorb excess CO 2, and thereby raise the pH. The amount of limewater required for this is not as great as if it were used as the main source to maintain high calcium levels and buffering properties. Addition of lime water can be done on a timer, at night or early in the morning when low pH values ​​are more likely. The addition of lime water can be carried out based on the readings of the pH controller, i.e. it can only be added when the pH value drops below a certain value (for example, below pH 7.8).

Low pH value caused by high indoor carbon dioxide levels

High levels of indoor carbon dioxide can also cause low pH in aquariums. The breathing of people and pets, the use of heating systems that burn natural gas (such as stoves and stoves) with inadequate ventilation, and the use of calcium reactors can lead to high levels of carbon dioxide indoors. The level of carbon dioxide indoors can easily be twice that of the outdoor air, and this excess can lead to a significant drop in pH in the aquarium. This problem is especially pressing in new, more hermetically sealed premises. This problem is unlikely to occur in older homes where wind can blow through the window frames.

Many aquarists have found that opening a window next to the aquarium can significantly raise the pH in one or two days. Unfortunately, aquarists living in cold climates may not be able to comfortably open their windows in the winter. Some of them have found that in such a situation it is useful to run a tube outside to the air intake of the flotator, in which fresh outside air is quickly mixed with the aquarium water. Keep in mind that if the aquarist lives in an area where insecticides are periodically sprayed to control mosquitoes (such as suburban areas in the south), an activated carbon filter should be installed on the air intake to prevent toxic chemicals from entering the aquarium.

Finally, using lime water (calcium hydroxide) is a good solution in many cases. Limewater can be especially effective because in this situation it is unlikely that the pH in the aquarium will rise to undesirably high levels, a danger that can accompany the use of limewater as the main source of calcium and buffering. Although calcium hydroxide is the most common and recognized additive for providing the necessary buffering in the aquarium, while raising the pH, other additives can be used to increase the pH. For example, in this situation, carbonate-based supplements will be very useful, but bicarbonate-based supplements will not. When considering commercial products, ESV's B-ionic is superior to the newer version (Bicarbonate B-ionic) from the same manufacturer. Washing soda (sodium carbonate) or calcined baking soda will be better than regular baking soda (sodium bicarbonate).

Low pH caused by low buffering capacity

Low buffering capacity can also result in low pH levels. For example, if the decrease in buffering capacity due to calcification is not compensated for, this can lead to a drop in pH. Such a drop is possible with all methods of buffering compensation, but will be most observed when using those systems that do not themselves increase the pH value (for example, a calcium reactor or the use of bicarbonates). In this case, the obvious solution is to increase the buffering capacity in some way, as shown in Figure 4.

Sudden drop in pH

All the cases described above refer to chronically low pH values. None of the options discussed address cases of sudden or temporary pH shifts. However, this can happen in some situations, and it will be useful to know what to do in such cases. Most aquarists are unlikely to do what I did, such as throwing a piece of dry ice into the sump just to see what happens. After doing this, I saw that the pH began to drop sharply. Similarly, you can easily see that a pH value of 5 can kill all life in the aquarium (in my case this did not happen, but I would not recommend you try to repeat this experiment for fun).

It is more likely that problems may arise with the release of large amounts of carbon dioxide as a result of a failure in the carbon dioxide supply system to the reactor. In most of these cases, I would advise doing nothing until the excess CO 2 has been removed by vigorous aeration. It may be worth opening a window so that the air involved in gas exchange itself does not contain excess CO 2. In about a day, the condition of the aquarium should return to normal. If the aquarist decides to add anything to increase the pH, he runs the risk of raising the pH value to too high a level 24 hours after excess CO 2 has been removed from the aquarium.

If the cause of the drop in pH is a mineral acid (for example, hydrochloric acid), the carbonate buffering (as well as the general buffering) will collapse. In this case, I would advise measuring the buffering capacity, and using carbonate buffering additives (not boron based) in order to raise the buffering capacity, returning it to normal levels (in the range of 2.5-4 meq/L or 7-11 dKH) . The end result of these actions should be an increase in pH. With some alkaline additives (limewater or regular B-ionic) the pH value can be restored quickly, while with others (like baking soda) the pH increase will occur slowly as the aquarium will need time to remove the resulting CO 2 .

If the cause of the drop in pH is vinegar or another organic acid, I would recommend the same measures as for hydrochloric acid, as discussed above. You just need to keep in mind that over time (from several hours to a day), the acetate formed from vinegar (acetic acid) will be oxidized to CO 2 and OH-. The result of this will be a possible increase in pH and alkalinity. Therefore, in this case it is better to limit or refrain from other actions that lead to an increase in buffering. If large amounts of buffering additives are used to stabilize the resulting acid, the pH and/or buffering may subsequently rise to higher values ​​than desired.

Conclusion

pH is an important saltwater aquarium indicator that most aquarists are familiar with. It has a serious impact on the health and well-being of the inhabitants of our systems, and we must do everything possible to ensure that this indicator lies within acceptable limits. This article provides tips for solving common problems associated with low pH in aquariums, allowing aquarists to diagnose and resolve low pH problems that may occur in aquariums.

Happy reefing!

If you have any questions about this article, please visit my author forum on ReefCentral.

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3. Chondrus crispus (Gigartinaceae, Rhodophyta) tank cultivation: optimizing carbon input by a fixed pH and use of a salt water well. Braud, Jean-Paul; Amat, Mireille A. Sanofi Bio-Industries, Polder du Dain, Bouin, Fr. Hydrobiologia (1996), 326/327 335-340.
4. Physiological ecology of Gelidiella acerosa. Rao, P. Sreenivasa; Mehta, V. B. Dep. Biosci., Saurashtra Univ., Rajkot, India. J. Phycol. (1973), 9(3), 333-
5. Studies on marine biological filters. Model filters. Wickins, J. F. Fish. Exp. Stn., Minist. Agric. Fish. Food, Conwy/Gwynedd, UK. Water Res. (1983), 17(12), 1769-80.
6. Physiological characteristics of Mycosphaerella ascophylli, a fungal endophyte of the marine brown alga Ascophyllum nodosum. Fries, Nils. Inst. Physiol. Bot., Univ. Uppsala, Uppsala, Sweden. Physiol. Plant. (1979), 45(1), 117-21.
7. pH dependent toxicity of five metals to three marine organisms. Ho, Kay T.; Kuhn, Anne; Pelletier, Marguerite C.; Hendricks, Tracey L.; Helmstetter, Andrea. National Health and Ecological Effects Research Laboratory, U.S. Environmental Protection Agency, Narragansett, RI, USA. Environmental Toxicology (1999), 14(2), 235-240.
8. Effects of lowered pH and elevated nitrate on coral calcification. Marubini, F.; Atkinson, M. J. Biosphere 2 Center, Columbia Univ., Oracle, AZ, USA. Mar. Ecol.: Prog. Ser. (1999), 188 117-121.
9. Effect of calcium carbonate saturation state on the calcification rate of an experimental coral reef. Langdon, Chris; Takahashi, Taro; Sweeney, Colm; Chipman, Dave; Goddard, John; Marubini, Francesca; Aceves, Heather; Barnett, Heidi; Atkinson, Marlin J. Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USA. Global Biogeochem. Cycles (2000), 14(2), 639-654.

pH value, pH(lat. pondus hydrogenii- “weight of hydrogen”, pronounced "peh") is a measure of the activity (in highly dilute solutions equivalent to the concentration) of hydrogen ions in a solution, which quantitatively expresses its acidity. Equal in magnitude and opposite in sign to the decimal logarithm of the activity of hydrogen ions, which is expressed in moles per liter:

History of the pH value.

Concept pH value introduced by the Danish chemist Sørensen in 1909. The indicator is called pH (according to the first letters of Latin words potentia hydrogeni- the strength of hydrogen, or pondus hydrogeni- weight of hydrogen). In chemistry by combination pX usually denote a quantity that is equal to log X, and the letter H in this case, denote the concentration of hydrogen ions ( H+), or, rather, the thermodynamic activity of hydronium ions.

Equations relating pH and pOH.

Display pH value.

In pure water at 25 °C the concentration of hydrogen ions ([ H+]) and hydroxide ions ([ OH− ]) turn out to be identical and equal to 10 −7 mol/l, this clearly follows from the definition of the ionic product of water, equal to [ H+] · [ OH− ] and equals 10 −14 mol²/l² (at 25 °C).

If the concentrations of two types of ions in a solution are the same, then the solution is said to have a neutral reaction. When an acid is added to water, the concentration of hydrogen ions increases, and the concentration of hydroxide ions decreases; when a base is added, on the contrary, the content of hydroxide ions increases, and the concentration of hydrogen ions decreases. When [ H+] > [OH− ] it is said that the solution turns out to be acidic, and when [ OH − ] > [H+] - alkaline.

To make it more convenient to imagine, to get rid of the negative exponent, instead of the concentrations of hydrogen ions, use their decimal logarithm, which is taken with the opposite sign, which is the hydrogen exponent - pH.

An indicator of the basicity of a solution pOH.

The reverse is slightly less popular pH value - solution basicity index, pOH, which is equal to the decimal logarithm (negative) of the concentration of ions in the solution OH − :

as in any aqueous solution at 25 °C, which means at this temperature:

pH values ​​in solutions of varying acidity.

• Contrary to popular belief, pH can vary beyond the range 0 - 14, and can also go beyond these limits. For example, at a concentration of hydrogen ions [ H+] = 10 −15 mol/l, pH= 15, at a hydroxide ion concentration of 10 mol/l pOH = −1 .

Because at 25 °C (standard conditions) [ H+] [OH − ] = 10 −14 , then it is clear that at such a temperature pH + pHOH = 14.

Because in acidic solutions [ H+] > 10 −7 , which means that for acidic solutions pH < 7, соответственно, у щелочных растворов pH > 7 , pH neutral solutions is equal to 7. At higher temperatures, the electrolytic dissociation constant of water increases, which means that the ionic product of water increases, then it will be neutral pH= 7 (which corresponds to simultaneously increased concentrations as H+, so OH−); with decreasing temperature, on the contrary, neutral pH increases.

Methods for determining pH value.

There are several methods for determining the value pH solutions. The hydrogen index is approximately estimated using indicators; measured accurately using pH-meter or determined analytically by performing acid-base titration.

1. For a rough estimate of the hydrogen ion concentration, it is often used acid-base indicators- organic dye substances, the color of which depends on pH environment. The most popular indicators: litmus, phenolphthalein, methyl orange (methyl orange), etc. Indicators can be in two differently colored forms - either acidic or basic. The color of all indicators changes within its own acidity range, often 1-2 units.
2. To increase the working measurement interval pH apply universal indicator, which is a mixture of several indicators. The universal indicator changes color sequentially from red through yellow, green, blue to violet when moving from an acidic region to an alkaline one. Definitions pH using the indicator method is difficult for cloudy or colored solutions.
3. Using a special device - pH-meter - makes it possible to measure pH over a wider range and more accurately (up to 0.01 units pH) than using indicators. Ionometric method of determination pH is based on measuring the emf of a galvanic circuit with a millivoltmeter-ionometer, which includes a glass electrode, the potential of which depends on the ion concentration H+ in the surrounding solution. The method is highly accurate and convenient, especially after calibrating the indicator electrode in the selected range pH, which makes it possible to measure pH opaque and colored solutions and is therefore often used.
4. Analytical volumetric method — acid-base titration— also gives accurate results for determining the acidity of solutions. A solution of known concentration (titrant) is added dropwise to the solution being tested. When they are mixed, a chemical reaction occurs. The equivalence point - the moment when there is exactly enough titrant to complete the reaction - is recorded using an indicator. After this, if the concentration and volume of the added titrant solution is known, the acidity of the solution is determined.
5. pH:

0.001 mol/L HCl at 20 °C has pH=3, at 30 °C pH=3,

0.001 mol/L NaOH at 20 °C has pH=11.73, at 30 °C pH=10.83,

Effect of temperature on values pH explained by different dissociation of hydrogen ions (H +) and is not an experimental error. The temperature effect cannot be compensated electronically pH-meter.

The role of pH in chemistry and biology.

The acidity of the environment is important for most chemical processes, and the possibility of occurrence or the result of a particular reaction often depends on pH environment. To maintain a certain value pH in the reaction system, when carrying out laboratory research or in production, buffer solutions are used that allow maintaining an almost constant value pH when diluted or when small amounts of acid or alkali are added to the solution.

pH value pH often used to characterize the acid-base properties of various biological media.

For biochemical reactions, the acidity of the reaction medium occurring in living systems is of great importance. The concentration of hydrogen ions in a solution often affects the physicochemical properties and biological activity of proteins and nucleic acids, therefore, for the normal functioning of the body, maintaining acid-base homeostasis is a task of exceptional importance. Dynamic maintenance of optimal pH biological fluids is achieved under the influence of the body's buffer systems.

In the human body, the pH value is different in different organs.

Some meanings pH.
Substance
Electrolyte in lead batteries
Gastric juice
Lemon juice (5% citric acid solution)
Food vinegar
Coca Cola
Apple juice
Healthy skin
Acid rain
Drinking water
Pure water at 25 °C
Sea water
Soap (fat) for hands
Ammonia
Bleach (bleach)
Concentrated alkali solutions

pH indicator and its impact on the quality of drinking water.

What is pH?

pH(“potentia hydrogeni” - the strength of hydrogen, or “pondus hydrogenii” - the weight of hydrogen) is a unit of measurement for the activity of hydrogen ions in any substance, quantitatively expressing its acidity.

This term appeared at the beginning of the twentieth century in Denmark. The pH indicator was introduced by the Danish chemist Soren Petr Lauritz Sorensen (1868-1939), although statements about a certain “power of water” are also found among his predecessors.

Hydrogen activity is defined as the negative decimal logarithm of the hydrogen ion concentration expressed in moles per liter:

pH = -log

For simplicity and convenience, the pH indicator was introduced in the calculations. pH is determined by the quantitative ratio of H+ and OH- ions in water, formed during the dissociation of water. It is customary to measure pH levels on a 14-digit scale.

If water has a reduced content of free hydrogen ions (pH greater than 7) compared to hydroxide ions [OH-], then the water will have alkaline reaction, and with an increased content of H+ ions (pH less than 7) - acid reaction. In perfectly pure distilled water, these ions will balance each other.

acidic environment: >
neutral environment: =
alkaline environment: >

When the concentrations of both types of ions in a solution are the same, the solution is said to be neutral. In neutral water the pH value is 7.

When various chemicals are dissolved in water, this balance changes, resulting in a change in pH value. When an acid is added to water, the concentration of hydrogen ions increases, and the concentration of hydroxide ions correspondingly decreases; when an alkali is added, on the contrary, the content of hydroxide ions increases, and the concentration of hydrogen ions decreases.

The pH indicator reflects the degree of acidity or alkalinity of the environment, while “acidity” and “alkalinity” characterize the quantitative content of substances in water that can neutralize alkalis and acids, respectively. As an analogy, we can give an example with temperature, which characterizes the degree of heating of a substance, but not the amount of heat. By putting our hand in the water, we can tell whether the water is cool or warm, but we will not be able to determine how much heat is in it (i.e., relatively speaking, how long this water will cool down).

pH is considered one of the most important indicators of drinking water quality. It shows the acid-base balance and influences how chemical and biological processes will proceed. Depending on the pH value, the rate of chemical reactions, the degree of corrosive aggressiveness of water, the toxicity of pollutants, etc. can change. Our well-being, mood and health directly depend on the acid-base balance of our body’s environment.

Modern man lives in a polluted environment. Many people purchase and consume food made from semi-finished products. In addition, almost every person is exposed to stress on a daily basis. All this affects the acid-base balance of the body's environment, shifting it towards acids. Tea, coffee, beer, carbonated drinks reduce pH in the body.

It is believed that an acidic environment is one of the main causes of cell destruction and tissue damage, the development of diseases and aging processes, and the growth of pathogens. In an acidic environment, building material does not reach the cells and the membrane is destroyed.

Externally, the state of the acid-base balance of a person’s blood can be judged by the color of his conjunctiva in the corners of his eyes. With an optimal acid-base balance, the color of the conjunctiva is bright pink, but if a person’s blood alkalinity increases, the conjunctiva becomes dark pink, and with an increase in acidity, the color of the conjunctiva becomes pale pink. Moreover, the color of the conjunctiva changes within 80 seconds after consuming substances that affect the acid-base balance.

The body regulates the pH of internal fluids, maintaining values ​​at a certain level. The body's acid-base balance is a certain ratio of acids and alkalis that contributes to its normal functioning. The acid-base balance depends on maintaining relatively constant proportions between intercellular and intracellular waters in the tissues of the body. If the acid-base balance of fluids in the body is not constantly maintained, normal functioning and preservation of life will be impossible. Therefore, it is important to control what you consume.

Acid-base balance is our indicator of health. The more “sour” we are, the sooner we age and get sick. For the normal functioning of all internal organs, the pH level in the body must be alkaline, in the range from 7 to 9.

The pH inside our body is not always the same - some parts are more alkaline and some are acidic. The body regulates and maintains pH homeostasis only in certain cases, such as blood pH. The pH levels of the kidneys and other organs whose acid-base balance is not regulated by the body are affected by the food and drinks we consume.

Blood pH

The blood pH level is maintained by the body in the range of 7.35-7.45. The normal pH of human blood is considered to be 7.4-7.45. Even a slight deviation in this indicator affects the ability of the blood to carry oxygen. If the blood pH rises to 7.5, it carries 75% more oxygen. When the blood pH drops to 7.3, it is already difficult for a person to get out of bed. At 7.29, he can fall into a coma; if the blood pH drops below 7.1, the person dies.

Blood pH levels must be maintained within a healthy range, so the body uses organs and tissues to maintain a constant pH level. Because of this, the pH level of the blood does not change due to drinking alkaline or acidic water, but the tissues and organs of the body used to regulate the pH of the blood do change their pH.

Kidney pH

The pH parameter of the kidneys is influenced by water, food, and metabolic processes in the body. Acidic foods (such as meat products, dairy products, etc.) and drinks (sweetened drinks, alcoholic drinks, coffee, etc.) lead to low pH levels in the kidneys because the body eliminates excess acidity through urine. The lower the urine pH level, the harder the kidneys have to work. Therefore, the acid load placed on the kidneys from such foods and drinks is called potential acid-renal load.

Drinking alkaline water benefits the kidneys - the urine pH level increases and the acid load on the body decreases. Increasing the pH of urine increases the pH of the body as a whole and rids the kidneys of acidic toxins.

Stomach pH

An empty stomach contains no more than a teaspoon of stomach acid produced at the last meal. The stomach produces acid as needed when eating food. The stomach does not produce acid when a person drinks water.

It is very useful to drink water on an empty stomach. The pH value increases to a level of 5-6. The increased pH will have a mild antacid effect and will lead to an increase in beneficial probiotics (good bacteria). Increasing the pH of the stomach increases the pH of the body, which leads to healthy digestion and relief from the symptoms of indigestion.

pH of subcutaneous fat

The body's fatty tissues have an acidic pH because excess acids are deposited in them. The body must store acid in fatty tissues when it cannot be excreted or neutralized by other means. Therefore, a shift in the body’s pH to the acidic side is one of the factors for excess weight.

The positive effect of alkaline water on body weight is that alkaline water helps remove excess acid from tissues because it helps the kidneys work more efficiently. This helps control weight because the amount of acid the body must “store” is greatly reduced. Alkaline water also improves the results of a healthy diet and exercise by helping the body deal with excess acidity produced by fat tissue during weight loss.

Bones

Bone has an alkaline pH because it is primarily composed of calcium. Their pH is constant, but if the blood needs pH adjustment, calcium is pulled from the bones.

The benefit of alkaline water to the bones is to protect them by reducing the amount of acid that the body has to fight against. Studies have shown that drinking alkaline water reduces bone resorption - osteoporosis.

Liver pH

The liver has a slightly alkaline pH, the level of which is affected by both food and drinks. Sugar and alcohol must be broken down in the liver, which leads to excess acid.

The benefits of alkaline water to the liver include the presence of antioxidants in such water; It has been found that alkaline water enhances the work of two antioxidants found in the liver, which contribute to more effective blood purification.

Body pH and alkaline water

Alkaline water allows the parts of the body that maintain the pH of the blood to function at greater efficiency. Increasing the pH levels in the parts of the body responsible for maintaining blood pH will help these organs stay healthy and functioning efficiently.

Between meals, you can help your body normalize its pH by drinking alkaline water. Even a small increase in pH can have a huge impact on your health.

According to research by Japanese scientists, the pH of drinking water, which is in the range of 7-8, increases the life expectancy of the population by 20-30%.

Depending on the pH level, water can be divided into several groups:

Strongly acidic waters< 3
acidic waters 3 - 5
slightly acidic waters 5 - 6.5
neutral waters 6.5 - 7.5
slightly alkaline waters 7.5 - 8.5
alkaline waters 8.5 – 9.5
highly alkaline waters > 9.5

Typically, the pH level of drinking tap water is within the range where it does not directly affect the consumer quality of water. In river waters the pH is usually in the range of 6.5-8.5, in precipitation 4.6-6.1, in swamps 5.5-6.0, in sea waters 7.9-8.3.

WHO does not offer any medically recommended value for pH. It is known that at low pH water is highly corrosive, and at high levels (pH>11) water acquires a characteristic soapiness, an unpleasant odor, and can cause irritation to the eyes and skin. That is why the optimal pH level for drinking and domestic water is considered to be in the range from 6 to 9.

Examples of pH values Substance Electrolyte in lead batteries <1.0 sour substances Gastric juice 1,0-2,0 Lemon juice 2.5±0.5 Lemonade, Cola 2,5 Apple juice 3.5±1.0 Beer 4,5 Coffee 5,0 Shampoo 5,5 Tea 5,5 Healthy skin ~6,5 Saliva 6,35-6,85 Milk 6,6-6,9 Distilled water 7,0 neutral substances Blood 7,36-7,44 alkaline substances Sea water 8,0 Soap (fat) for hands 9,0-10,0 Ammonia 11,5 Bleach (bleach) 12,5 Soda solution 13,5

Interesting to know: The German biochemist OTTO WARBURG, awarded the Nobel Prize in Physiology or Medicine in 1931, proved that lack of oxygen (acidic pH<7.0) в тканях приводит к изменению нормальных клеток в злокачественные.

The scientist discovered that cancer cells lose the ability to develop in an environment saturated with free oxygen with a pH of 7.5 or higher! This means that when body fluids become acidic, cancer development is stimulated.

His followers in the 60s of the last century proved that any pathogenic flora loses the ability to reproduce at pH = 7.5 and above, and our immune system easily copes with any aggressors!

To preserve and maintain health, we need proper alkaline water (pH=7.5 and above). This will make it possible to better maintain the acid-base balance of body fluids, since the main living environments have a slightly alkaline reaction.

Already in a neutral biological environment, the body can have an amazing ability to self-heal.

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Typically, an indicator such as pH or blood acidity (hydrogen indicator, acid-base balance parameter, pH), as patients are accustomed to calling it, is not noted in the referral for hematological tests to examine the patient. Being a constant value, the pH of human blood can change its values ​​only within strictly designated limits - from 7.36 to 7.44 (on average - 7.4). Increased blood acidity (acidosis) or a shift in pH to the alkaline side (alkalosis) are conditions that do not develop as a result of exposure to favorable factors and in most cases require immediate therapeutic measures.

The blood cannot withstand a pH drop below 7 and a rise to 7.8, which is why such extreme pH values ​​such as 6.8 or 7.8 are considered unacceptable and incompatible with life. In some sources, the high limit of compatibility with life may differ from the listed values, that is, equal to 8.0.

Blood buffer systems

A person’s blood constantly receives products of an acidic or basic nature, but for some reason nothing happens? It turns out that everything is provided in the body, to guard the constancy of pH, buffer systems are on duty around the clock, which resist any changes and do not allow the acid-base balance to shift in a dangerous direction. So, in order:

• Opens a list of buffer systems bicarbonate system, it is also called hydrocarbonate. It is considered the most powerful, since it takes on a little more than 50% of all blood buffering abilities;
• Takes second place hemoglobin buffer system, it provides 35% of the total buffer capacity;
• Third place belongs to blood protein buffer system- to 10%;
• In fourth position is phosphate system, which accounts for about 6% of all buffer capabilities.

These buffer systems, in maintaining a constant pH, are the first to resist a possible shift in the pH value in one direction or another, because the processes that support the vital activity of the body are ongoing, and at the same time, products of either an acidic or basic nature are constantly released into the blood. Meanwhile, for some reason the buffer capacity is not depleted. This happens because the excretory system (lungs, kidneys) comes to the rescue, which reflexively turns on whenever there is a need - it removes all the accumulated metabolites.

How do the systems work?

Main buffer system

The activity of the bicarbonate buffer system, which includes two components (H2CO3 and NaHCO3), is based on the reaction between them and bases or acids entering the blood. If it appears in the blood strong alkali, then the reaction will follow this path:

NaOH + H2CO3 → NaHCO3 + H2O

The sodium bicarbonate formed as a result of the interaction does not stay in the body for a long time and, without having any special effect, is removed by the kidneys.

For presence strong acid the second component of the bicarbonate buffer system, NaHCO3, will react, which neutralizes the acid as follows:

HCl + NaHCO3 → NaCl + H2CO3

The product of this reaction (CO2) will quickly leave the body through the lungs.

The hydrocarbonate buffer system is the first to “feel” a change in the pH value, so it is the first to begin its work.

Hemoglobin and other buffer systems

The main component of the hemoglobin system is the red blood pigment - Hb, the pH of which changes by 0.15 depending on whether it currently binds oxygen (pH shift to the acidic side) or releases it to tissues (shift to the alkaline side). Adapting to circumstances, hemoglobin plays the role of either a weak acid or a neutral salt.

On admission reasons The following reaction can be expected from the hemoglobin buffer system:

NaOH + HHb → NaHb + H2O (pH remains almost unchanged)

And with acid, as soon as it appears, hemoglobin will begin to interact as follows:

HCl + NaHb → NaCl + HHb (pH shift is not very noticeable)

The buffering capacity of proteins depends on their basic characteristics (concentration, structure, etc.), therefore the buffer system of blood proteins is not as involved in maintaining acid-base balance as the previous two.

The phosphate buffer system or sodium phosphate buffer does not produce a special shift in the blood pH value. It maintains pH values ​​at the proper level in the fluids that fill the cells and in the urine.

pH in arterial and venous blood, plasma and serum

Is the main parameter of acid-base balance – pH in arterial and venous blood – somewhat different? Arterial blood is more stable in terms of acidity. But, in principle, the pH norm in oxygenated arterial blood is 0.01 - 0.02 higher than in blood flowing through the veins (pH in venous blood is lower due to excess CO2 content).

As for the pH of blood plasma, then, again, in plasma the balance of hydrogen and hydroxyl ions, in general, corresponds to the pH of whole blood.

pH values ​​may vary in other biological media, for example, in serum, but plasma that has left the body and is deprived of fibrinogen is no longer involved in maintaining vital processes, so its acidity is more important for other purposes, for example, for the production of sets of standard hemagglutinating serums, which determine a person's group affiliation.

Acidosis and alkalosis

A shift in pH values ​​in one direction or another (acid → acidosis, alkaline → alkalosis) can be compensated or uncompensated. It is determined by the alkaline reserve, represented mainly by bicarbonates. Alkaline reserve (ALR) is the amount of carbon dioxide in milliliters displaced by a strong acid from 100 ml of plasma. The norm of SH is within the range of 50 – 70 ml of CO2. Deviation from these values ​​indicates uncompensated acidosis (less than 45 ml CO2) or alkalosis (more than 70 ml CO2).

There are the following types of acidosis and alkalosis:

Acidosis:

• Gas acidosis– develops when the removal of carbon dioxide by the lungs slows down, creating a condition;
• Non-gas acidosis– is caused by the accumulation of metabolic products or their entry from the gastrointestinal tract (alimentary acidosis);
• Primary renal acidosis– represents a reabsorption disorder in the renal tubules with the loss of a large amount of alkalis.

Alkalosis:

• Gas alkalosis– occurs with increased release of CO2 by the lungs (altitude sickness, hyperventilation), creates a condition hypocapnia;
• Non-gas alkalosis– develops with an increase in alkaline reserves due to the supply of bases with food (nutritional) or due to changes in metabolism (metabolic).

Of course, it will most likely not be possible to restore the acid-base balance in acute conditions on your own, but at other times, when the pH is almost at the limit, and the person does not seem to be in any pain, all responsibility falls on the patient himself.

Products that are considered harmful, as well as cigarettes and alcohol, are usually the main cause of changes in blood acidity, although a person does not know about it unless it comes to acute pathological conditions.

You can lower or increase the pH of the blood with the help of diet, but we should not forget: as soon as a person switches to his favorite lifestyle again, the pH values ​​will return to their previous levels.

Thus, maintaining the acid-base balance requires constant work on oneself, recreational activities, a balanced diet and proper regimen, otherwise all short-term work will be in vain.