Map of lead content in tap water. Russian water map. Boron consumption standards

Water quality characterizes the amount of chemical, microbiological and radiological contamination. Let's consider only some of the chemical indicators of water quality

Hydrogen value (pH)

The hydrogen index or pH is the logarithm of the concentration of hydrogen ions, taken with the opposite sign, i.e. pH = -log.

The pH value is determined by the quantitative ratio of H+ and OH- ions in water, formed during the dissociation of water. If OH- ions predominate in water - that is, pH> 7, then the water will have an alkaline reaction, and with an increased content of H+ ions - pH<7- кислую. В дистиллированной воде эти ионы будут уравновешивать друг друга и рН будет приблизительно равен 7. При растворении в воде различных химических веществ, как природных, так и антропогенных, этот баланс нарушается, что приводит к изменению уровня рН.

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

Depending on the pH value, the flow rate may change chemical reactions, the degree of corrosiveness of water, the toxicity of pollutants and much more.

Typically, the pH level is within the range at which it does not affect the consumer quality of water. In river waters, the pH is usually in the range of 6.5-8.5; in swamps, the water is more acidic due to humic acids- there the pH is 5.5-6.0, in groundwater the pH is usually higher. At high levels (pH>11), water acquires a characteristic soapiness, an unpleasant odor, and can cause irritation to the eyes and skin. Low pH<4 тоже может вызывать неприятные ощущения. Влияет pH и на жизнь aquatic organisms. For drinking and domestic water, the optimal pH level is considered to be in the range from 6 to 9.

Hardness of water

Water hardness is associated with the content of dissolved calcium and magnesium salts in it. The total content of these salts is called total hardness. The total hardness of water is divided into carbonate hardness, determined by the concentration of hydrocarbonates (and carbonates at pH 8.3) of calcium and magnesium, and non-carbonate hardness - the concentration of calcium and magnesium salts of strong acids in the water. Since when water boils, bicarbonates turn into carbonates and precipitate, carbonate hardness is called temporary or removable. The hardness remaining after boiling is called constant. The results of determining water hardness are expressed in mEq/dm3. Temporary or carbonate hardness can reach up to 70-80% of the total water hardness.

Water hardness is formed as a result of the dissolution of rocks containing calcium and magnesium. Calcium hardness, caused by the dissolution of limestone and chalk, predominates, but in areas where there is more dolomite than limestone, magnesium hardness may also predominate.

Water hardness analysis is important primarily for groundwater of different depths and for waters of surface streams originating from springs. It is important to know the hardness of water in areas where there are outcrops of carbonate rocks, primarily limestone.

Sea and ocean waters have high hardness. High water hardness worsens the organoleptic properties of water, giving it a bitter taste and having a negative effect on the digestive organs. High hardness promotes the formation of urinary stones and salt deposition. It is hardness that causes scale to form in kettles and other water boiling devices. When washing, hard water dries out the skin and makes it difficult to lather when using soap.

The value of the total hardness in drinking water According to experts, it should not exceed 2-3.0 mg-eq/dm3. Special requirements are placed on process water for various industries, since scale simply disables expensive water heating equipment and significantly increases energy costs for heating water.

Smell

Chemically pure distilled water is tasteless and odorless. However, such water does not occur in nature - it always contains dissolved substances - organic or mineral. Depending on the composition and concentration of impurities, water begins to take on a particular taste or smell.

The reasons for the appearance of odor in water can be very different. This is the presence of biological particles in water - rotting plants, mold fungi, protozoa (ferruginous and sulfur bacteria are especially noticeable), and mineral pollutants. Anthropogenic pollution greatly worsens the smell of water - for example, the ingress of pesticides, industrial and domestic wastewater, and chlorine into the water.

Odor belongs to the so-called organoleptic indicators and is measured without the help of any instruments. The intensity of the odor of water is determined expertly at 20°C and 60°C and measured in points:

The smell is not noticeable 0 points.

The smell is not felt by the consumer, but is detected during laboratory testing -1 point.

The smell is noticed by the consumer, if you draw his attention to it - 2 points.

The smell is easily noticed and causes a disapproving review of the water -3 points.

The smell attracts attention and makes you refrain from drinking -4 points.

The smell is so strong that it makes the water unfit for consumption - 5 points.

Turbidity

Water turbidity is caused by the presence of fine suspended matter of organic and inorganic origin.

Suspended substances enter the water as a result of washing away solid particles (clay, sand, silt) of the top cover of the earth by rain or melt water during seasonal floods, as well as as a result of erosion of river beds. As a rule, the turbidity of surface waters is much higher than the turbidity of groundwater. The lowest turbidity of water bodies is observed in winter, the highest in spring during floods and in summer, during rains and the development of the smallest living organisms and algae floating in the water. In running water, turbidity is usually less.

Water turbidity can be caused by a variety of reasons - the presence of carbonates, aluminum hydroxides, high-molecular organic impurities of humic origin, the appearance of phyto- and isoplankton, as well as the oxidation of iron and manganese compounds by atmospheric oxygen.

High turbidity is a sign of the presence of certain impurities in the water, possibly toxic; in addition, various microorganisms develop better in muddy water, incl. pathogenic. In Russia, water turbidity is determined photometrically by comparing samples of the water being tested with standard suspensions. The measurement result is expressed in mg/dm3 when using a basic standard suspension of kaolin or in TU/dm3 (turbidity units per dm3) when using a basic standard suspension of formazin.

General mineralization

Total mineralization is a total quantitative indicator of the content of substances dissolved in water. This parameter is also called the content of soluble substances or total salt content, since substances dissolved in water are usually found in the form of salts. The most common include inorganic salts (mainly bicarbonates, chlorides and sulfates of calcium, magnesium, potassium and sodium) and small amounts organic matter, soluble in water.

Do not confuse mineralization with dry residue. The method for determining the dry residue is such that volatile organic compounds dissolved in water are not taken into account. Total mineralization and dry residue may differ by a small amount (usually no more than 10%).

The level of salinity in drinking water is determined by the quality of water in natural sources (which varies significantly in different geological regions due to different solubility of minerals). The water of the Moscow region is not particularly highly mineralized, although in those watercourses that are located in areas where readily soluble carbonate rocks emerge, mineralization may increase.

Depending on the mineralization (g/dm3 - g/l), natural waters can be divided into the following categories:

Ultra-fresh< 0.2
Fresh 0.2 - 0.5
Waters with relatively high mineralization 0.5 - 1.0
Salty 1.0 - 3.0
Salty 3 - 10
High salinity waters 10 - 35
Pickles > 35

In addition to natural factors, the overall salinity of water is greatly influenced by industrial wastewater, urban storm drains (when salt is used to de-ice roads), etc.

The taste of water is considered good if the total salt content is up to 600 mg/l. According to organoleptic indications, WHO recommends an upper limit of mineralization of 1000 mg/l (i.e., to the lower limit of brackish waters). Mineral waters with a certain salt content are beneficial to health only according to doctor's indications in strictly limited quantities. For industrial water, the mineralization standards are stricter than for drinking water, since even relatively small concentrations of salts damage equipment, settle on the walls of pipes and clog them.

Oxidability

Oxidability is a value characterizing the content of organic and minerals oxidized (at certain conditions) one of the strong chemical oxidizing agents. This indicator reflects the total concentration of organic matter in water. The nature of organic substances can be very different - humic acids of soils, complex organic matter of plants, and chemical compounds anthropogenic origin. To identify specific compounds, use various methods.

There are several types of water oxidation: permanganate, dichromate, iodate. Most high degree oxidation is achieved using the dichromate method. In water treatment practice, permanganate oxidation is determined for natural, slightly polluted waters, and in more polluted waters, as a rule, dichromate oxidation (COD - “chemical oxygen demand”) is determined.

Permanganate oxidability is expressed in milligrams of oxygen used to oxidize these substances contained in 1 dm3 of water.

The amount of oxidizability of natural waters can vary widely from fractions of milligrams to tens of milligrams of O2 per liter of water. Surface waters have a higher oxidizability compared to groundwater. This is understandable - organic matter from soil and plant litter gets into surface water more easily than into groundwater, which is most often limited by clay aquifers. The water of lowland rivers, as a rule, has an oxidability of 5-12 mg O2 / dm3, rivers fed by swamps - tens of milligrams per 1 dm3. Groundwater has an average oxidizability at a level from hundredths to tenths of a milligram of O2/dm3. Although groundwater in areas of oil and gas fields and peatlands can have very high oxidizability.

Dry residue

Dry residue characterizes the total content in water mineral salts, which is calculated by summing the concentration of each of them, excluding volatile organic compounds. Water is considered fresh if it has a total salt content of no more than 1 g/l.

For industrial water, the mineralization standards are stricter than for drinking water, since even relatively small concentrations of salts damage equipment, settle on the walls of pipes and clog them.
Inorganic substances

Aluminum

Aluminum is a lightweight silvery-white metal. It enters water primarily during the water treatment process - as part of coagulants. In case of technological violations of this process, it may remain in the water. Sometimes it gets into water with industrial wastewater. The permissible concentration is 0.5 mg/l.

Excess aluminum in water leads to damage to the central nervous system.

Iron

Iron enters water when rocks dissolve. Iron can be washed out of them by groundwater. An increased iron content is observed in swamp waters, in which it is found in the form of complexes with salts of humic acids. Groundwater in the strata of Jurassic clays is saturated with iron. Clays contain a lot of pyrite FeS, and iron from it passes into water relatively easily.

The iron content in surface fresh waters is tenths of a milligram. An increased iron content is observed in swamp waters (a few milligrams), where the concentration of humic substances is quite high. The highest concentrations of iron (up to several tens of milligrams per 1 dm3) are observed in groundwater with low values ​​and low content, and in areas of sulfate ores and zones of young volcanism, iron concentrations can reach even hundreds of milligrams per 1 liter of water. In surface waters middle zone Russia contains from 0.1 to 1 mg/l of iron; in groundwater the iron content often exceeds 15-20 mg/l.

Significant amounts of iron enter water bodies with wastewater from metallurgical, metalworking, textile, paint and varnish industries and agricultural runoff. Iron analysis for wastewater is very important.

The concentration of iron in water depends on the pH and oxygen content of the water. Iron in the water of wells and boreholes can be in both oxidized and reduced forms, but when the water settles, it always oxidizes and can precipitate. A lot of iron is dissolved in acidic anoxic groundwater.

Water analysis for iron is necessary for the most different types water - surface natural water, near-surface and deep underground water, wastewater from industrial enterprises.

Water containing iron (especially underground water) is initially transparent and clean in appearance. However, even with short contact with atmospheric oxygen, iron oxidizes, giving the water a yellowish-brown color. Already at iron concentrations above 0.3 mg/l, such water can cause rusty streaks on plumbing fixtures and stains on laundry during washing. When the iron content is above 1 mg/l, the water becomes cloudy, turns yellow-brown, and has a characteristic metallic taste. All this makes such water practically unacceptable for both technical and drinking use.

The human body needs iron in small quantities - it is part of hemoglobin and gives the blood its red color. But too high concentrations of iron in water are harmful to humans. The iron content in water above 1-2 mg/dm3 significantly worsens the organoleptic properties, giving it an unpleasant astringent taste. Irritant effect on mucous membranes and skin, hemochromatosis, allergies. Iron increases the color and turbidity of water.

Cadmium

Cadmium is a chemical element of group II of the periodic system of elements D.I. Mendeleev; white, shiny, heavy, soft, malleable metal.

Cadmium enters natural waters through the leaching of soils, polymetallic and copper ores, as a result of the decomposition of aquatic organisms capable of accumulating it. The maximum permissible concentration of cadmium in drinking water for Russia is 0.001 mg/m3, for EU countries - 0.005 mg/m3. Cadmium compounds are carried into surface waters with wastewater from lead-zinc plants, ore processing plants, and a number of chemical enterprises(production of sulfuric acid), galvanic production, as well as with mine water. A decrease in the concentration of dissolved cadmium compounds occurs due to the processes of sorption, precipitation of cadmium hydroxide and carbonate and their consumption by aquatic organisms.

Dissolved forms of cadmium in natural waters are mainly mineral and organomineral complexes. The main suspended form of cadmium is its sorbed compounds. A significant portion of cadmium can migrate within the cells of aquatic organisms.

Excessive intake of cadmium into the body can lead to anemia, liver damage, cardiopathy, emphysema, osteoporosis, skeletal deformation, and the development of hypertension. The most important thing in cadmiosis is kidney damage, expressed in dysfunction renal tubules and glomeruli with slower tubular reabsorption, proteinuria, glucosuria, followed by aminoaciduria, phosphaturia. An excess of cadmium causes and enhances a deficiency of Zn and Se. Long-term exposure can cause kidney and lung damage and weakening of bones.

Symptoms of cadmium poisoning: protein in the urine, damage to the central nervous system, acute bone pain, genital dysfunction. Cadmium affects blood pressure, can cause the formation of kidney stones (it accumulates especially intensively in the kidneys). Everyone is a danger chemical forms cadmium

Potassium

Potassium is a chemical element of group I of the periodic system of elements D.I. Mendeleev; silver-white, very light, soft and fusible metal.

Potassium is found in feldspars and micas. On the earth's surface, potassium, unlike sodium, migrates weakly. When rocks weather, potassium partially passes into water, but from there it is quickly captured by organisms and absorbed by clays, so river waters are poor in potassium and much less of it enters the ocean than sodium. The maximum permissible concentration of potassium in drinking water for EU countries is 12.0 mg/dm3.

Distinctive feature potassium - its ability to cause increased excretion of water from the body. Therefore, diets with increased content elements facilitate operation of cardio-vascular system if it is insufficient, it causes the disappearance or significant reduction of edema. Potassium deficiency in the body leads to dysfunction of the neuromuscular (paresis and paralysis) and cardiovascular systems and is manifested by depression, incoordination of movements, muscle hypotonia, hyporeflexia, convulsions, arterial hypotension, bradycardia, ECG changes, nephritis, enteritis and etc. Daily requirement in potassium 2-3 g.

Calcium

Calcium occurs in nature only in the form of compounds. The most common minerals are diopside, aluminosilicates, calcite, dolomite, and gypsum. Weathering products of calcium minerals are always present in soil and natural waters. Dissolution is promoted by micro biological processes decomposition of organic substances, accompanied by a decrease in pH.

Large amounts of calcium are carried out with wastewater from silicate, metallurgical, chemical industries and with wastewater from agricultural enterprises, and especially when using calcium-containing mineral fertilizers.
Characteristic feature calcium is the tendency to form fairly stable supersaturated solutions of CaCO3 in surface waters. Quite stable complex compounds of calcium with organic substances contained in water are known. In low-mineralized colored waters, up to 90-100% of calcium ions can be bound with humic acids.

In river waters, the calcium content rarely exceeds 1 g/l. Usually its concentration is much lower.

The concentration of calcium in surface waters has noticeable seasonal fluctuations: in the spring the content of calcium ions is increased, which is associated with the ease of leaching of soluble calcium salts from the surface layer of soils and rocks.
Calcium is important for all forms of life. In the human body it is part of bone, muscle tissue and blood. The mass of calcium contained in the human body exceeds 1 kg, of which 980 g is concentrated in the skeleton.

Long-term consumption of water with a high content of calcium salts can cause urolithiasis, sclerosis and hypertension in people. Calcium deficiency causes bone deformation in adults and rickets in children.
Strict requirements are imposed on the calcium content in the waters feeding steam power plants, since in the presence of carbonates, sulfates and a number of other anions, calcium forms a strong scale. Data on the calcium content in water are also necessary when solving issues related to the formation of the chemical composition of natural waters, their origin, as well as when studying calcium-carbonate equilibrium.

The maximum permissible concentration for calcium is 180 mg/l.

Silicon

Silicon is one of the most common chemical elements on Earth. The main source of silicon compounds in natural waters is the processes of chemical weathering and dissolution of silicon-containing minerals and rocks. But silicon has low solubility and, as a rule, there is not much of it in water.

Silicon also gets into water with industrial wastewater from enterprises producing ceramics, cement, glass products, and silicate paints. Maximum permissible concentration of silicon - 10 mg/l

Manganese

Manganese - chemical element Group VII periodic table of elements D.I. Mendeleev. Metal.

Manganese activates a number of enzymes, participates in the processes of respiration, photosynthesis, and affects hematopoiesis and mineral metabolism. A lack of manganese in the soil causes necrosis, chlorosis, and spotting in plants. With a lack of this element in feed, animals lag behind in growth and development, their mineral metabolism is disrupted, and anemia develops. On soils poor in manganese (carbonate and over-limed), manganese fertilizers are used. The maximum permissible concentration of manganese in water in Russia is 0.1 mg/dm3. When the maximum permissible concentration of manganese is exceeded, a mutagenic effect on humans and damage to the central nervous system are noted. It is especially dangerous if such water is systematically consumed by pregnant women; in 90 percent of cases, it leads to congenital deformities of the child.

Arsenic

Arsenic is one of the most famous poisons. It is a metal that is toxic to most living things. Its maximum permissible concentration in water is 0.05 mg/l. Arsenic poisoning affects the central and peripheral nervous system, skin, peripheral vascular system.

Inorganic arsenic is more dangerous than organic arsenic, and trivalent arsenic is more dangerous than pentavalent arsenic. The main source of arsenic in water is industrial waste.

Sodium

Sodium is one of the main components of the chemical composition of natural waters, determining their type.

The main source of sodium entering land surface waters are igneous and sedimentary rocks and native soluble sodium chloride, sulfate and carbon dioxide salts. Biological processes that result in the formation of soluble sodium compounds are also of great importance. In addition, sodium enters natural waters with domestic and industrial wastewater and with water discharged from irrigated fields.

In surface waters, sodium migrates predominantly in a dissolved state. Its concentration in river waters ranges from 0.6 to 300 mg/l, depending on the physical and geographical conditions and geological features of water bodies. In groundwater, the sodium concentration varies widely - from milligrams to tens of grams per liter. This is determined by the depth of groundwater and other hydrogeological conditions.

The biological role of sodium is critical to most life forms on Earth, including humans. The human body contains about 100 g of sodium. Sodium ions activate enzymatic metabolism in the human body. Excess sodium in water and food leads to hypertension and hypertension.

The maximum permissible concentration for potassium is 50 mg/l.

Nickel

Nickel is a chemical element of the first triad of group VIII of the periodic system of elements D.I. Mendeleev; a silvery-white metal, malleable and ductile.

On Earth, nickel is almost always found together with cobalt and mainly in the form of a mixture of nickel compounds with cobalt and arsenic (kupfernickel), with arsenic and sulfur (nickel luster), with iron, copper and sulfur (pentlandite) and other elements. Industrial nickel deposits (sulfide ores) are usually composed of nickel and copper minerals. In the biosphere, nickel is a relatively weak migrant. There is relatively little of it in surface waters and living matter. The maximum permissible concentration of nickel in drinking water in Russia is 0.1 mg/l, in EU countries - 0.05 mg/l.

Nickel - essential microelement in the human body, in particular for the regulation of DNA exchange. However, its intake in excess quantities can pose a health hazard. It affects the blood and gastrointestinal tract.

Mercury

Mercury - in normal conditions- liquid, volatile metal. A very dangerous and toxic substance. The maximum permissible concentration of mercury in water is only 0.0005 mg/l.

Mercury affects the central nervous system, especially in children, blood, kidneys, and causes reproductive dysfunction. Particularly dangerous is methylmercury, a metal-organic compound formed in water in the presence of mercury. Methylmercury is very easily absorbed by body tissues and takes a very long time to be eliminated from it.

Almost all water pollution with mercury is of artificial origin - mercury enters natural watercourses from industrial wastewater.

Lead

Lead is a chemical element of group IV of the periodic system of elements D.I. Mendeleev; heavy metal of bluish-gray color, very ductile, soft.

The concentration of lead in natural waters usually does not exceed 10 µg/l, which is due to its precipitation and complexation with organic and inorganic ligands; the intensity of these processes largely depends on pH. The maximum permissible concentration of lead in drinking water is: for EU countries - 0.05 mg/dm3, for Russia - 0.03 mg/dm3.

Lead water testing is important for surface water drinking water and wastewater. It is necessary to test the water for lead content if there is suspicion of industrial effluent entering the watercourse.

Plants absorb lead from soil, water and precipitation. Lead enters the human body through food (about 0.22 mg), water (0.1 mg), and dust (0.08 mg).

For all regions of Ukraine, lead is the main anthropogenic toxic element from the group heavy metals, which is associated with high industrial pollution and emissions from motor vehicles running on leaded gasoline. Lead accumulates in the body, bones and surface tissues. Lead affects the kidneys, liver, nervous system and blood-forming organs. The elderly and children are especially sensitive to even low doses of lead.

Zinc

Zinc is found in water in the form of salts and organic compounds. At high concentrations it gives water an astringent taste. Zinc can disrupt metabolism; it especially disrupts the metabolism of iron and copper in the body.

Zinc enters water with industrial wastewater, is washed out of galvanized pipes and other communications, and can accumulate and enter water from ion exchange filters.

Fluorine

The fluorine cycle in nature covers the lithosphere, hydrosphere, atmosphere and biosphere. Fluoride is found in surface, ground, sea and even meteoric waters.

Drinking water with a fluoride concentration of more than 0.2 mg/l is the main source of its entry into the body. Water from surface sources is characterized by predominantly low fluorine content (0.3-0.4 mg/l). High levels of fluoride in surface waters are a consequence of the discharge of industrial fluoride-containing wastewater or contact of water with soils rich in fluoride compounds. Maximum concentrations fluorine (5-27 mg/l or more) is determined in artesian and mineral waters in contact with fluorine-containing water-bearing rocks.
Inorganic compounds

Ammonium

Ammonium ion (NH4+) - in natural waters accumulates when gas - ammonia (NH3) is dissolved in water, formed during the biochemical decomposition of nitrogen-containing organic compounds. Dissolved ammonia enters the reservoir with surface and underground runoff, precipitation, and wastewater. In nature, it is formed during the decomposition of nitrogen-containing organic compounds. It is a pollutant of both natural and industrial waters. Ammonia is present in wastewater from livestock farms and some industrial production. It can get into the water due to technological violations of the ammoniation process - treating drinking water with ammonia a few seconds before chlorination to ensure a longer disinfecting effect. As a rule, ammonia concentrations in water do not reach dangerous levels, but it reacts with other compounds, resulting in more toxic substances.

The presence of ammonium ions and nitrites in concentrations exceeding background values ​​indicates fresh pollution and the proximity of the source of pollution (municipal wastewater treatment plants, industrial waste settling tanks, livestock farms, accumulations of manure, nitrogen fertilizers, settlements, etc.).

Hydrogen sulfide

Hydrogen sulfide - H2S - is a fairly common water pollutant. It is formed during the decay of organic matter. Significant volumes of hydrogen sulfide are released to the surface in volcanic areas, but for our area this route is not significant. In our surface and underground watercourses, hydrogen sulfide is released during the decomposition of organic compounds. There can be especially a lot of hydrogen sulfide in the bottom layers of water or in groundwater - in conditions of oxygen deficiency.

In the presence of oxygen, hydrogen sulfide quickly oxidizes. To accumulate it you need restorative conditions.

Hydrogen sulfide can enter watercourses with wastewater from chemical, food, pulp production, and city sewerage.

Hydrogen sulfide is not only toxic, it has a strong, unpleasant odor (smell rotten eggs), which sharply worsens the organoleptic properties of water, making it unsuitable for drinking water supply. The appearance of hydrogen sulfide in the bottom layers is a sign acute shortage oxygen and the development of death phenomena in the reservoir.

Sulfates

Sulfates are present in almost all surface waters. The main natural source of sulfates is the processes of chemical weathering and dissolution of sulfur-containing minerals, mainly gypsum, as well as the oxidation of sulfides and sulfur. Significant amounts of sulfates enter water bodies in the process of the death of living organisms and the oxidation of terrestrial and aquatic substances of plant and animal origin.

Of the anthropogenic sources of sulfates, first of all it is necessary to mention mine waters and industrial wastewater from industries that use sulfuric acid. Sulfates are also carried out with wastewater utilities and agricultural production.

Sulfates participate in the sulfur cycle. In the absence of oxygen, under the action of bacteria, they are reduced to hydrogen sulfide and sulfides, which, when oxygen appears in natural water, are again oxidized to sulfates. Plants and bacteria extract sulfates dissolved in water to build protein substances. After living cells die during decomposition, protein sulfur is released in the form of hydrogen sulfide, which is easily oxidized to sulfates in the presence of oxygen.

Elevated sulfate contents worsen the organoleptic properties of water and have a physiological effect on the human body - they have laxative properties.

Sulfates in the presence of calcium can form scale, so their content is strictly regulated in industrial waters.

Nitrates

Water pollution with nitrates can be due to both natural and anthropogenic causes. As a result of the activity of bacteria in water bodies, ammonium ions can transform into nitrate ions; in addition, during thunderstorms, a certain amount of nitrates appears during electrical discharges - lightning.

The main anthropogenic sources of nitrates entering water are the discharge of domestic wastewater and runoff from fields where nitrate fertilizers are used.

The highest concentrations of nitrates are found in surface and near-surface groundwater, the lowest in deep wells. It is very important to test water from wells, springs, and tap water for nitrate content, especially in areas with developed agriculture.
An increased content of nitrates in surface water bodies leads to their overgrowing; nitrogen, as a biogenic element, promotes the growth of algae and bacteria. This is called the process of eutrophication. This process is very dangerous for reservoirs, since the subsequent decomposition of plant biomass will consume all the oxygen in the water, which, in turn, will lead to the death of the fauna of the reservoir.

Nitrates are also dangerous for humans. A distinction is made between the primary toxicity of the nitrate ion itself; secondary, associated with the formation of nitrite ion, and tertiary, due to the formation of nitrosamines from nitrites and amines. The lethal dose of nitrates for humans is 8-15 g. With prolonged consumption of drinking water and food products containing significant amounts of nitrates, the concentration of methemoglobin in the blood increases. The blood's ability to carry oxygen decreases, which leads to adverse consequences for the body.

Nitrites

Nitrites are an intermediate step in the chain of bacterial processes of ammonium oxidation to nitrates or, conversely, the reduction of nitrates to nitrogen and ammonia. Similar redox reactions are typical for aeration stations, water supply systems and natural waters. The highest concentrations of nitrites in water are observed in summer, which is associated with the activity of certain microorganisms and algae.

Water analysis for nitrites is done for waters of surface and near-surface watercourses.

Nitrites can be used in industry as preservatives and corrosion inhibitors. In wastewater they can end up in open watercourses.

An increased content of nitrites indicates an increase in the processes of decomposition of organic substances under conditions of slow oxidation of NO2- into NO3-, this indicates pollution of the reservoir. Nitrite content is an important sanitary indicator.

Chlorides

Almost all natural waters, rainwater, and wastewater contain chloride ions. Their concentrations vary widely from a few milligrams per liter to quite high concentrations V sea ​​water. The presence of chlorides is explained by the presence in the rocks of the most common salt on Earth - sodium chloride. The increased content of chlorides is explained by pollution of the reservoir with wastewater.

Free chlorine (free active chlorine) is chlorine present in water in the form of hypochlorous acid, hypochlorite ion, or dissolved elemental chlorine.

Combined chlorine is part of the total chlorine present in water in the form of chloramines or organic chloramines.

Total chlorine (total residual chlorine) is chlorine present in water as free chlorine or combined chlorine or both.
Organic compounds

Benzene

Benzene is one of the most troublesome organic water pollutants. Its permissible concentration is 0.01 mg/l. Typically, benzene contamination of water is of industrial origin. It enters water in wastewater from chemical industries, during oil and coal production.

Benzene affects the central nervous system, blood (can contribute to the development of leukemia), liver, adrenal glands. In addition, benzene can react with other substances to form other toxic compounds. When reacting with chlorine, dioxins can be formed.

Phenol

Phenols are derivatives of benzene with one or more hydroxyl groups. They are usually divided into two groups - phenols that are volatile with steam (phenol, cresols, xylenols, guaiacol, thymol) and non-volatile phenols (resorcinol, pyrocatechol, hydroquinone, pyrogallol and other polyhydric phenols).

Phenols under natural conditions are formed in the metabolic processes of aquatic organisms, during the biochemical decomposition and transformation of organic substances occurring both in the water column and in bottom sediments.

Phenols are one of the most common pollutants entering surface waters with wastewater from oil refining, shale processing, timber chemical, coke chemical, aniline paint industries, etc. In the wastewater of these enterprises, the content of phenols can exceed 10-20 g/dm3 in very diverse combinations. In surface waters, phenols can be dissolved in the form of phenolates, phenolate ions and free phenols. Phenols in waters can enter into condensation and polymerization reactions, forming complex humus-like and other fairly stable compounds. Under the conditions of natural reservoirs, the processes of adsorption of phenols by bottom sediments and suspensions play a minor role.

In unpolluted or slightly polluted river waters, the content of phenols usually does not exceed 20 μg/dm3. Exceeding the natural background may indicate pollution of water bodies. In natural waters contaminated with phenols, their content can reach tens and even hundreds of micrograms per liter. The maximum permissible concentration for phenols in water for Russia is 0.001 mg/dm3.

Water analysis for phenol is important for natural and waste waters. It is necessary to test water for phenol content if there is a suspicion of contamination of watercourses with industrial effluents.

Phenols are unstable compounds and are subject to biochemical and chemical oxidation. Polyhydric phenols are destroyed mainly by chemical oxidation.

However, when treating water containing phenol impurities with chlorine, very dangerous organic toxicants - dioxins - can be formed.

The concentration of phenols in surface waters is subject to seasonal changes. In summer, the content of phenols decreases (with increasing temperature, the rate of decomposition increases). The release of phenolic waters into reservoirs and watercourses sharply worsens their general sanitary condition, affecting living organisms not only with their toxicity, but also with a significant change in the regime of nutrients and dissolved gases (oxygen, carbon dioxide). As a result of chlorination of water containing phenols, stable compounds of chlorophenols are formed, the slightest traces of which (0.1 μg/dm3) give the water a characteristic taste.

Formaldehyde

Formaldehyde - CH2O - an organic compound. Its other name is formic aldehyde.

The main source of water pollution with formaldehyde is anthropogenic activity. Wastewater, the use of materials made from low-quality polymers in water supply, emergency discharges - all this leads to formaldehyde getting into the water. It is found in industrial wastewater organic synthesis, plastics, varnishes, paints, leather, textile and pulp and paper industries.

In natural waters, formaldehyde decomposes quite quickly with the help of microorganisms.

Formaldehyde affects the central nervous system, lungs, liver, kidneys, and organs of vision. Formaldehyde is a carcinogen. Its maximum permissible concentration in water is 0.05 mg/l

Water is eliminated from our body through urine, sweat, feces and even breathing - while removing harmful and toxic substances. In addition, such a process is necessary for the functioning of our bodies. On a hot day, an adult loses about 1.5 liters of water through sweat alone. The worst thing is that in hot weather the body temperature constantly increases and if there is not enough water in the body, a person can die from heatstroke. Water in in this case cools the body and lowers body temperature.

Lead in drinking water
The composition of lead in water is regulated by GOST - no more than 0.03 mg/l.
The particular danger of lead is that it can accumulate in the body and is poorly excreted from it.

Lead poses a risk to people of all ages, but especially to children and pregnant women. The consequences of lead accumulation are associated with the ability to cause premature birth in women, reduce the weight of children at birth, inhibit their physical and mental development. Long-term exposure to lead can lead to anemia (anemia) due to its ability to inhibit the formation of hemoglobin; muscle weakness; hyperactivity; aggressive behavior. In adults, lead can stimulate hypertension and cause hearing loss.

Means for reducing lead in drinking water:
---Use only cold water for drinking and cooking as hot water better removes lead from plumbing fixtures;
---Before drawing water from the tap, let it drain for a few minutes, especially when the tap has not been used for several hours. This way, the lead that has transferred from the plumbing fittings will be washed away;
---Most effective method reducing the amount of lead in water is the use of special filters from activated carbon, which reduce its concentration in water by 80-90%. This process is called adsorption.

Volatile organic compounds in water
Volatile organic compounds (VOCs) in water include:
benzene, carbon tetrachloride, vinyl chloride, toluene, dichloroethane and others.
With prolonged exposure to VOCs, the following diseases can occur: cancer, damage to the kidneys, nervous system, and liver.

Bacteria in water
Bacteria can be found in water, which can lead to food poisoning, dysentery, and dysfunction. gastrointestinal tract, stomach ulcers, actinomycosis and other diseases, in addition to corrosion of water pipes.

Prevention bacterial diseases: (do not pollute the water)
---boiling water;
---using filters.

Chlorine in water
Chlorine is widely used to disinfect water from bacteria, viruses and other microorganisms.
Chlorine is one of the chemical elements that is a gaseous substance and is a strong oxidizing agent, as well as a highly toxic substance. There are several concerns regarding the presence of chlorine in water:

1) This is a water quality problem. If there is an excessive amount of chlorine in it, then it gives it an unpleasant smell and taste.

2) These are diseases that chlorine can cause. It was found that people who drink chlorinated water have a 21% higher risk of bladder cancer and a 38% higher risk of colorectal cancer than those who drink water with little chlorine (but no one had ever chlorinated their water before.)

The problem is also effect of chlorinated methane. These compounds appear in water under the influence of chlorine, when it contains harmless impurities, including light organic compounds. The action of chlorine-substituted methane also leads to the occurrence oncological diseases.

A significant amount of chlorine in water can be detected organoleptically (using the senses, perception). However, in small quantities it is very difficult to determine the presence of chlorine.

Radon in water.
Radon is a radioactive element that occurs when naturally occurring uranium or thorium decays.
Radon is also found in cigarette smoke and water. Radon is a colorless, odorless chemical radioactive inert gas.

In water, radon poses a twofold danger:

1) water, which can cause malignant tumors stomach and kidneys;

2) inhalation of air where radon passes from water, especially in the bathroom and kitchen.

Ways to reduce radon in water:
Boiling - when boiling, a significant amount of radon evaporates, and it is necessary to organize an exhaust hood in the room where the water is boiled. Using filters on activated carbon also reduces radon concentrations.
Reducing radon in the air: ventilation of the bathroom and kitchen, no smoking in the premises. Smoking causes a risk of lung cancer 10-20 times greater than that of non-smokers.

Nitrates and nitrites
They enter the human body with food and water, causing disruption of cell respiration.
Main symptoms: cyanosis of the face, lips, visible mucous membranes, headache, increased fatigue, decreased performance, shortness of breath, palpitations, loss of consciousness and death - with severe poisoning.
Chronic (systematic) ingestion of nitrates into the body of newborns and children is especially dangerous. younger age, since it is long oxygen starvation may cause disruption of growth and formation of the body, delayed physical and mental development, disruption of the functioning of the cardiovascular system, promotion of the development of cancer, birth defects development. Nitrites are more toxic than nitrates.

The sources of nitrates entering the human body are:
---vegetables and fruits
---meat and fish products (especially in raw smoked sausages)
---cheeses (used in production)
---water - when providing the population with water from open reservoirs, rivers

Intense accumulation of nitrates and nitrites occurs when food is stored at room temperature: in dirty and damp rooms, with high humidity.

Chopping and grinding vegetables creates good conditions for the reproduction of microorganisms that accumulate nitrates and nitrites.

The reasons for the deterioration and contamination of drinking water (and water in general - after all, all water can be drunk if it is clean) are given below:

1) Draining of technical water by enterprises into reservoirs, and simply into the ground (on the surface or into a hole - it doesn’t matter), or storage in the open air, burying any waste or garbage.
2) Harmful emissions into the atmosphere by enterprises and transport of toxic substances - which during rain penetrate into the ground with water, which we then drink and wash and prepare to eat.
3) Lack of harmless technologies for production, transport, and waste disposal.
4) Lack of practice of widespread free introduction of environmentally friendly and safe technologies, energy sources, means of transportation and production
5) Lack of self-awareness and conscience among the inhabitants of planet Earth.

Why do you need a water quality (analysis) map? Types of water supply sources for populated areas. Factors influencing the quality and composition of natural waters. Regulatory documents for assessing drinking water indicators. Maximum permissible indicators for organoleptic and toxicological properties of water. What it shows and how to use the analysis card. Water quality (analysis) card Russian Federation will help you find out how clean and quality water in your region, which microelements predominate in it, the map will provide complete information about the hardness and composition of the water.

Main sources of water intake

The quality of your tap water depends on the climatic and geological characteristics of your region, because water is taken for the needs of the population's water supply from natural water sources.

All surface waters can be divided into lake-type reservoirs, river basins, swampy formations and marine reservoirs. Water intake for the water supply system can be carried out from rivers, lakes, as well as from underground water accumulations (artesian wells, wells).

Before drawing conclusions about the suitability of water from any water body for use for economic and domestic purposes, it is necessary to conduct chemical analysis, which will allow us to identify the presence of all kinds of microorganisms and elements in the composition, as well as draw conclusions about their impact on human health.

As you already understand, the quality of drinking water in your region is directly related to the quality and characteristics of surface waters on land or deep sources from which water is drawn for the water supply system of a populated area. In turn, the quality of natural waters may depend on the following factors:

  • Terrain. As water passes through obstacles, it becomes saturated with oxygen.
  • The presence of certain vegetation along the banks of the reservoir. A large number of fallen leaves in a pond contributes to an increased level of ion exchange resins.
  • Soil composition. So, if the soil contains a lot of limestone rocks, then the water in the reservoirs will be clear, but with high hardness. And soils with a high content of dense impermeable rocks produce soft water of high turbidity.
  • Amount of sunlight. The more it is, the more favorable the environment for the development of various microorganisms in water. This includes not only bacteria and fungi, but also representatives of aquatic flora and fauna.
  • All kinds natural disasters may lead to sudden change composition and quality of water.
  • The volume and frequency of precipitation also influence the characteristics of the aquatic environment.
  • Production and economic activity human impact on the composition and quality of drinking water. For example, emissions from some plants can be deposited into natural waters, causing pollution with nitrogen or sulfur particles.
  • But we should not forget about the general environmental situation in the region.

Water quality

Of course, the water analysis card contains all the data about chemical composition waters in your region. But it is very difficult to understand them without knowledge of water quality standards. To assess the quality of drinking water, the following regulatory documents in force in Russia are used: GOST 2874-82 and SanPiN 2.1.4.1074-01.

  1. Organoleptic standards for drinking water describe acceptable color values, taste qualities, transparency and odor of the liquid. Some of them are rated on a 5-point scale, while others are assessed using degrees or volume per liter. So that you can draw your own conclusions about the quality of water in your region, we provide a table of standards for the organoleptic characteristics of drinking water:

The upper limit for water turbidity and color is considered normal only during the flood period. The rest of the time, the maximum permissible value is considered to be the first number.

  1. Toxicological standards for drinking water make it possible to regulate the level of harmful substances. human body components. Thus, the current regulatory documents indicate their maximum permissible concentration, at which a person cannot be harmed, provided that he drinks such water throughout his life. To analyze water quality by toxicological characteristics You can use the table of acceptable indicators:
Substance Maximum permissible norm
SanPiN 2.1.4.1074-01 GOST 2874-82
Barium elements 0.1 mg/l —
Aluminum inclusions 0.2 (0.5) mg/l 0.5 mg/l
Molybdenum particles — 0.25 mg/l
Beryllium components — 0.0002 mg/l
Arsenic 0.01 mg/l 0.05 mg/l
Selenium content 0.01 mg/l 0.001 mg/l
Elements of strontium — 7.0 mg/l
Polyacrylomide residue — 2.0 mg/l
Lead 0.01 mg/l 0.03 mg/l
Nickel elements 0.1 mg/l —
Fluorine particles 1.5 mg/l 0.7-1.5 mg/l
Presence of nitrates 45.0 mg/l 45.0 mg/l

Water quality map

To compile this map, water samples were taken from various sources of water supply to settlements, namely rivers, lakes, springs, wells, boreholes, etc. After all the necessary analyzes were carried out in an accredited laboratory, the data was plotted on a map.

How to use the online map http://www.watermap.ru/map on the network:

  • You can view the analysis results for all tested parameters.
  • For each sample, the source where the water was taken is separately indicated with exact coordinates. Thanks to this, you can easily find the source of clean drinking water closest to you.
  • All sources on the map are colored in one of three colors: red, green or yellow. The color selection occurs automatically depending on the test results and compliance or exceedance of MPC indicators for a given source.

Color interpretation:

  • green color indicates that the analyzed indicators are 30% below the upper limit of the norm;
  • yellow color indicates that one or more analyzed values ​​reach the upper normal threshold;
  • red color indicates that one or more indicators have exceeded the upper acceptable threshold.

The main sources of soil contamination with lead are atmospheric fallout, both local (industrial enterprises, thermal power plants, vehicles, mining, etc.), and the results of transboundary transfer. For agricultural soils, the introduction of lead compounds with mineral fertilizers (especially phosphorus), as well as the removal along with the harvest, is important. Thus, in 1990, 29.7 tons of lead were supplied to the soils of the Non-Chernozem Zone of Russia with phosphorus fertilizers.

The greatest contamination with heavy metals occurs in soils and plants within a radius of 2–5 km from metallurgical enterprises, 1–2 km from mines and thermal power plants, and in a zone of 0–100 m from highways.
Local soil contamination with lead-containing objects (used batteries, pieces of lead-sheathed cables, etc.) is also significant. The latter is especially noticeable near settlements, where the direct impact of industry and vehicles very often leads to multiple excesses of the maximum permissible concentrations of lead in the soil.

The degree of soil contamination with lead is relatively low. The average content of gross forms of lead in sandy and sandy loam soils is 6.8±0.6 mg/kg, in soils of loamy and clayey granulometric composition with an acidic reaction (pHsol< 5,5), - 9,6±0,5 мг/кг; в тех же почвах, но имеющих реакцию среды, близкую к нейтральной (рНсол >5.5), - 12.0±0.3 mg/kg. This indicates the accumulation of bulk forms of lead in soils with a high content of clay fraction. As soil acidity decreases, lead concentration also increases. Exceeding the approximately permissible concentrations (from 32 to 130 mg/kg for different groups of soils) for lead content was found only in one reference site in the Moscow region. Exceeding the level of 0.5 approximately permissible concentrations was detected in a number of reference areas of the Karachay-Cherkess Republic, the Republic of Tyva, and the Vologda Region.

Areas with low lead content in soils (up to 10 mg/kg) occupy about 28% of the territory of Russia, mainly in its northwestern part. Within this region, soddy-podzolic loamy and sandy loam soils developed on moraine deposits, as well as acidic podzolic soils depleted in microelements, predominate; Lots of wetlands.

Territories with a lead content in soils of 20–30 mg/kg (approximately 7%) are represented by various soils, as well as soddy-podzolic soils, gray forest soils and others. Relatively high content lead in these soils is associated with its entry into environment both from industrial enterprises and through transport.

The lead content in soils of populated areas is much higher. According to 20-year studies by network laboratories of Roshydromet, the highest levels of lead in soil are observed in a 5-kilometer zone around non-ferrous metallurgy enterprises. Of the information presented on the map for Russian cities, in 80% of cases there are significant excesses of the approximately permissible concentrations of lead in the soil. More than 10 million urban residents come into contact with soil that, on average, exceeds the estimated permissible concentrations of lead. The population of a number of cities is exposed to average concentrations of lead in the soil that are more than 10 times higher than the estimated permissible concentrations: Revda and Kirovgrad in the Sverdlovsk region; Rudnaya Pristan, Dalnegorsk and in the Primorsky Territory; Komsomolsk-on-Amur in the region; Belovo in Kemerovo region; Svirsk, Cheremkhovo in the Irkutsk region, etc. In most cities, the lead content varies within the range of 30–150 mg/kg with an average value of about 100 mg/kg.

Many cities, having a “prosperous” average picture in terms of lead contamination, they are significantly polluted over a significant part of their territory. Thus, in Moscow, the concentration of lead in the soil varies from 8 to 2000 mg/kg. The soils most contaminated with lead are in the central part of the city, within the district railway and near it. More than 86 km2 of the city territory (8%) is contaminated with lead in concentrations exceeding the approximately permissible concentration. At the same time, in the same places, as a rule, other toxic substances are present in concentrations exceeding the maximum permissible concentration (cadmium, zinc, copper), which significantly aggravates the situation due to their synergism.

- 1.2900 mg/l which is 4.30 times higher than normal. (Normal: 0.3000 mg/l)

Description of the chemical element

Iron (Fe)- chemical element of group VIII of the periodic table, atomic number 26. It is one of the most common in earth's crust metals Iron is usually called its alloys with a low content of impurities: steel, cast iron and stainless steel.

Functions of iron

  • The main source for the synthesis of hemoglobin, which is the carrier of oxygen molecules in the blood.
  • Participates in the synthesis of collagen, which forms the basis of the connective tissues of the human body: tendons, bones and cartilage. Iron makes them strong.
  • Participates in oxidative processes in cells. Without iron, the formation of red blood cells, which regulate redox mechanisms already at the embryonic stage of brain development, is impossible. If this process fails, the child may be born defective.

Iron intake standards

  • Physiological requirement for adults per day: for men 10 mg; for women – 15 mg.
  • The physiological need for children per day is from 4 to 18 mg.
  • The maximum permissible daily dose is 45 mg.

Dangerous doses of iron

  • Toxic dose – 200 mg.
  • Lethal dose – 7-35 g.

Maximum permissible concentration (MPC) of iron in water – 0.3 mg/l

Iron hazard class – 3 (hazardous)

High concentration

In this area, there is a high iron content in the water, which significantly worsens its properties, giving an unpleasant astringent taste, and makes the water of little use. Exceeding the maximum permissible concentration of iron in water carries the following health risks:

  • allergic reactions;
  • blood and liver diseases (hemochromatosis);
  • negative impact on reproductive function body (infertility);
  • atherosclerosis and heart attack;
  • toxic effects with a complex of symptoms: diarrhea, vomiting, a sharp decline pressure, kidney inflammation and paralysis of the nervous system.

Exceeding the concentration of this element leads to risks: , ,


The presence of these elements in water increases health risks:


The water in this area does not exceed the content of chemical elements:

Description of the chemical element

Chromium (Cr)- chemical element of group VI of the periodic table, atomic number 24. It is a solid metal of bluish-white color. Is a microelement.

May be present in water in the form of Cr3+ and toxic chromium in the form of dichromates and chromates.

Chrome functions

  • Regulates carbohydrate metabolism: Together with insulin, it participates in the metabolism of sugar.
  • Transport of proteins.
  • Promotes growth.
  • Prevents and reduces high blood pressure.
  • Prevents the development of diabetes.

Chromium consumption standards

  • For adult men and women, the required daily dose of chromium is 50 mg.
  • The required daily dose of chromium for children from 1 year to 3 years is 11 mg;
    • from 3 to 11 years – 15 mg;
    • from 11 to 14 years – 25 mg.

There are no official data on the maximum permissible daily intake of chromium.

Maximum permissible concentration (MPC) of chromium in water – 0.05 mg/l

Chromium hazard class – 3 (hazardous)

Low concentration

In this area, the chromium content does not exceed the maximum permissible concentration in water. A deficiency of chromium consumed in water and food can lead to the development of the following pathological conditions:

  • changes in blood glucose levels;
  • may contribute to the development of atherosclerosis and diabetes.

Description of the chemical element

Cadmium (Cd)- chemical element of group II of the periodic table, atomic number 48. It is a soft, malleable, malleable metal of silver-white color.

In water, cadmium is present in the form of Cd2+ ions and belongs to the class of toxic heavy metals.

In the body, cadmium is found in a special protein called metallothionein.

Functions of cadmium

  • The function of cadmium in thionein is to bind and transport heavy metals and detoxify them.
  • Activates several zinc-dependent enzymes: tryptophan oxygenase, DALK dehydratase, carboxypeptidase.

Cadmium consumption standards

The following doses of aluminum compounds are considered toxic to humans (mg/kg body weight):

  • An adult’s body receives 10-20 mcg of cadmium per day. However, it is believed that the optimal intensity of cadmium intake should be 1-5 mcg.

Maximum permissible concentration (MPC) of cadmium in water – 0.001 mg/l

Cadmium hazard class – 2 (highly dangerous)

Low concentration

In this area, the cadmium content does not exceed the maximum permissible concentration in water. Cadmium deficiency in the body can develop with insufficient intake (0.5 mcg/day or less), which can lead to growth retardation.

Health risks

  • risk of developing diseases of the nervous system
  • risk of developing kidney disease
  • risk of developing heart and vascular diseases
  • risk of developing blood diseases
  • risk of developing dental and bone diseases
  • risk of developing skin diseases and hair loss

Description of the chemical element

Lead (Pb)- chemical element of group IV of the periodic table, atomic number 82. It is a malleable, relatively low-melting gray metal.

Lead is present in water in the form of Pb2+ cations and belongs to the class of toxic heavy metals.

Lead functions

  • Affects growth.
  • Participates in metabolic processes bone tissue.
  • Participates in iron metabolism.
  • Affects hemoglobin concentration.
  • Changes the actions of some enzymes.

Lead consumption standards

It is believed that the optimal rate of lead intake into the human body is 10-20 mcg/day.

Dangerous doses of lead

  • Toxic dose – 1 mg.
  • Lethal dose – 10 g.

Maximum permissible concentration (MPC) of lead in water – 0.03 mg/l

Lead hazard class – 2 (highly dangerous)

Low concentration

In this area, the lead content does not exceed the maximum permissible concentration in water. Lead deficiency in the body can develop with insufficient intake of this element (1 mcg/day or less). There is currently no data on the symptoms of lead deficiency in the human body.

Description of the chemical element

Fluorine (F)- chemical element of group VII of the periodic table, atomic number 9. It is a chemically active non-metal and the strongest oxidizing agent, and is the lightest element from the halogen group. Very poisonous.

In the body, fluorine is in a bound state, usually in the form of sparingly soluble salts with calcium, magnesium, and iron. Fluorine is the main component of mineral metabolism; fluorine compounds are part of all tissues human body. The highest fluoride content is in bones and teeth.

Functions of fluorine

  • Depends on fluorine:
    • condition of bone tissue, its strength and hardness;
    • proper formation of skeletal bones;
    • condition and growth of hair, nails and teeth.
  • Fluoride, together with calcium and phosphorus, prevents the development of caries - it penetrates microcracks in tooth enamel and smoothes them out.
  • Participates in the process of hematopoiesis.
  • Supports immunity.
  • Provides prevention of osteoporosis, and in case of fractures accelerates bone healing.
  • Thanks to fluoride, the body better absorbs iron and gets rid of heavy metal salts and radionuclides.

Fluoride consumption standards

  • For adult men and women, the daily dose of fluoride is 4 mg.
  • Daily dose of fluoride for children:
    • from 0 to 6 months – 1 mg;
    • from 6 months to 1 year – 1.2 mg;
    • from 1 year to 3 years – 1.4 mg;
    • from 3 to 7 years – 3 mg;
    • from 7 to 11 years – 3 mg;
    • from 11 to 14 years – 4 mg.
  • The maximum permissible daily dose is 10 mg

Dangerous doses of fluoride

  • Toxic dose – 20 mg.
  • Lethal dose – 2 g.

Maximum permissible concentration (MAC) of fluorine in water:

  • Fluorine for climatic region I-II – 1.5 mg/l;
  • Fluorine for climatic region III – 1.2 mg/l;
  • Fluorine for climatic region IV is 0.7 mg/l.

Fluorine hazard class – 2 (highly dangerous)

Low concentration

In this area, the fluorine content does not exceed the maximum permissible concentration. It should be remembered that a deficiency of fluoride consumed in water and food can lead to the following diseases and conditions:

  • the appearance of dental caries (when the fluorine content in water is less than 0.5 mg/l, the phenomenon of fluoride deficiency develops and caries occurs);
  • bone damage (osteoporosis);
  • underdevelopment of the body, in particular the skeleton and teeth.

Description of the chemical element

Boron (B)- chemical element of group III of the periodic system, atomic number 5. It is a colorless, gray or red crystalline or dark amorphous substance.

Boron functions

  • Participates in the metabolism of calcium, magnesium, phosphorus.
  • Promotes growth and regeneration of bone tissue.
  • It has antiseptic and antitumor properties.

Boron consumption standards

The daily intake of boron is 2 mg.

Upper permissible level consumption – 13 mg.

Dangerous doses

  • Toxic dose – from 4 g.

Maximum permissible concentration (MAC) of boron in water – 0.5 mg/l

Boron hazard class – 2 (highly dangerous)

Low concentration

In this area, the boron content does not exceed the maximum permissible concentration in water. Water does not pose any health risks. However, a lack of boron consumed through water and food can lead to:

  • to deterioration of mineral metabolism of bone tissue;
  • growth retardation;
  • osteoporosis;
  • urolithiasis;
  • decreased intelligence;
  • retinal dystrophy.

Russia, Ural Federal District, Chelyabinsk region, Kopeysk

These samples exceeded the maximum permissible concentration:


This leads to the following health risks.

Loading...Loading...