The water we drink. Lead in water

Skin rashes and stains on the teeth are the most innocent things that bad tap water can reward us with. In every region of Russia, tap water has its drawbacks: it does not bother citizens to learn more about them.

Text: Ruslan Bazhenov

WITH sulfates

Exceeding the maximum permissible concentration (hereinafter referred to as MPC) of sulfates in drinking water leads to a decrease in the acidity of gastric juice, diarrhea. With a five-fold excess of the norm (maximum concentration limit - up to 500 mg / l), they are significantly accelerated. This excess is typical for tap water Rostov, Samara, Kurgan regions and Altai Territory.

In regions with even a double excess of sulfates (for example, in Central Asia), the local population gets used to them, while visitors immediately experience "interruptions" in work gastrointestinal tract.

Nitrates and nitrites

V human body nitrates are reduced to nitrites, and those, in turn, interact with hemoglobin, forming a stable compound - methemoglobin. As you know, hemoglobin carries oxygen, but methemoglobin does not have this ability. As a result, tissues begin to experience oxygen starvation, a disease develops - nitrate methemoglobinemia. Outbreaks of this disease, mostly among children, have been reported around the world in regions with high levels of nitrates in water. All sick children drank water containing nitrates from 18 to 257 mg/l (in Russia, MPC for nitrates is 45 mg/l). The content of nitrates in drinking water, three or more times higher than the norm, takes place in the Rostov, Lipetsk, Bryansk, Tula and Voronezh regions.

Fluorides

For Russia, the exact opposite problem is relevant - an excess of fluorine. Studies have shown that when the content of fluorine in water in the amount of 5-7 mg / l develops a pronounced osteosclerosis (compaction bone tissue), and at 10-20 mg / l in children there is a significant

Fluorosis is provided to residents who drink water with a fluorine content of 2 mg/l, while the recommended by the World Health Organization (WHO) level of fluorine in drinking water is 1.5 mg/l. A number of cities and districts of the Moscow, Tver, Penza and Vladimir regions, the Republic of Bashkortostan, Mordovia and the Krasnodar Territory fall into the risk zone, where the fluorine content in the water exceeds the norm. For example, in such cities of the Moscow region as Vidnoye, Podolsk, Yegorievsk, Odintsovo, Krasnogorsk, fluorosis was detected in 25 percent of the population.

The press, manufacturers of bottled water and fluoridated toothpastes are willing to exaggerate the alleged problem of a lack of fluoride in Russian tap water. But in fact, the amount of fluorine (0.01 mg / l), which, being insufficient, and leads to caries, practically does not occur in the water sources of our country. This is evidenced by data from a study of the Gorno-Altai state university. In fairness, we add that on the question of how much fluoride is required to prevent caries, the scientific community has not yet come to a consensus.

Iron

Iron in a concentration three times higher than the norm (maximum concentration limit - 0.3 mg / l) is present in the water supply systems of the Tomsk, Vologda, Tambov, Arkhangelsk, Chelyabinsk, Tver, Novosibirsk regions. Such an excess leads to itching, dryness and rashes on the skin; increases the likelihood of development.

Iron of natural origin enters drinking water from underground sources in the central and southern regions of Russia, as well as the Siberian region. In addition, an increased concentration of iron occurs when using steel and cast iron water pipes, which collapse due to corrosion. Particularly unfavorable in this regard is St. Petersburg, where soft water enhances corrosion.

Iodine

Sad fact: 65% of the Russian population drinks water with insufficient iodine content. The average consumption of iodine in our country is 40-80 micrograms per day per person, which is half the physiological requirement. Lack of iodine leads to the development of Graves' disease, delays in the physical and. Water iodization, which they tried to put forward as a countermeasure, turned out to be ineffective, as, indeed, salt iodization.

B rum

The content of bromine in the underground sources of the Eastern Trans-Urals exceeds the standards by 40 times (maximum concentration limit - 0.2 mg / l) - in such concentrations it contributes to the development of pathologies of the cardiovascular system,. The analysis of statistical data has revealed a direct correlation between the indicators of general mortality of the population and the content of bromine in drinking water in this region.

M manganese

Manganese in a concentration exceeding the norm (maximum concentration limit - 0.1 mg / l) three times, is contained in the tap water of the Tomsk, Vologda, Tambov, Arkhangelsk, Chelyabinsk, Tver, Novosibirsk regions. In a number scientific research it has been established that such an amount of manganese negatively affects, has a toxic and mutagenic effect on the human body. The content of manganese in drinking water directly depends on the activities of nearby industrial enterprises.

Accumulating in the tissues of the brain, mercury leads to severe nerve damage, contributes to disruption of the cardiovascular system. Even small doses are dangerous: the lower limits of mercury content in drinking water, at which it would not accumulate in the body, have not yet been established. One of the main sources (85%) of mercury in the environment is the activity of industrial enterprises. Excess of hygienic standards was revealed in the Belgorod and Vologda regions. However, the natural high content of mercury in the water of some regions, for example, in the Altai Mountains, also plays a role.

Lead

Lead is most dangerous for children and pregnant women. In children - lowers IQ, provokes the development of heart defects. In women, it increases, toxicosis and the birth of children with developmental defects, and in addition, leads to infertility.

Exceeding the MPC (norm - 0.03 mg/l) of lead is observed in the drinking water of the Kaluga and Ryazan regions. The main source of lead in tap water is the destruction of lead-containing elements of water supply networks (solders, brass alloys).

And aluminum

It has a significant neurotoxic effect, causing an early onset. In addition, aluminum leaches calcium from the body, which is especially dangerous for a growing organism. Exceeding the maximum allowable concentration of aluminum (the norm is 0.5 mg/l) was recorded in the drinking water of the Arkhangelsk, Samara and Omsk regions. The main source of aluminum in tap water are substances used in the process of water treatment at treatment plants - coagulants.

X loroform

American researchers have established a direct correlation between the content of chloroform in drinking water and an increase in the number of cancers.

In the process of chlorination of tap water, chloroform is formed, and in fairly high concentrations. WHO sets the MPC for chloroform at 0.03 mg/l, which, according to many researchers, is an outrageous underestimation of the danger of this substance. But also worse situation in Russia, where the MPC for chloroform is many times higher than the WHO standards - 0.2 mg / l!

Exceeding the MPC of organochlorine compounds was recorded in the drinking water of the Kemerovo, Nizhny Novgorod, Perm, Sverdlovsk regions, St. Petersburg.

Surfactants (surfactants)

They have a lot of negative qualities: from heavy metals; dissolve liquid and solid contaminants, which, if not for surfactants, would settle on the filters; serve as a breeding ground for dangerous microorganisms. Enhanced Level The content of surfactants was noted in the rivers - these are the Volga, Oka, Kama, Irtysh, Don, Northern Dvina, Ob, Tom, Tobol, Neva.

Water is excreted 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 work of our organs. On a hot day, an adult only sweats about 1.5 liters of water. The worst thing is that in the heat the body temperature constantly increases and if there is not enough water in the body, then a person can die from heat stroke. Water in this case cools the body and lowers body temperature.

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

Lead is dangerous for people of all ages, and especially for children and pregnant women. The consequences of lead accumulation are associated with the ability to cause premature birth in women, reduce the birth weight of children, and 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 behaviour. In adults, lead can stimulate hypertension and cause hearing loss.

Means for reducing the lead content in drinking water:
---For drinking and cooking use only cold water, insofar as hot water better washes lead from plumbing fittings;
---Before drawing water from the faucet, let it drain for a few minutes, especially when the faucet has not been used for several hours. Thus, the lead that has passed from the parts of the plumbing fittings will be washed away;
---The most effective way to reduce the amount of lead in water is to use special filters made of activated carbon which reduce its concentration in water by 80-90%. This process is called adsorption.

Volatile organic compounds in water
Volatile organic compounds in water (VOCs) include:
benzene, carbon tetrachloride, vinyl chloride, toluene, dichloroethane and others.
Prolonged exposure to VOCs may cause the following diseases: cancer, kidney damage, nervous system, liver.

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

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

Chlorine in water
Chlorine is widely used to disinfect water from bacteria, viruses and other microorganisms.
Chlorine is one of the chemical elements, which 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 excess amount of chlorine in it, then it gives it bad smell and taste.

2) These are diseases that chlorine can cause. People who drink chlorinated water have been found to be at increased risk of cancer Bladder 21% higher and a 38% higher risk of rectal cancer than those who drink water with a small amount of chlorine (but no one has chlorinated the water before.)

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

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

Radon in water.
Radon is a radioactive element that comes from the decay of natural uranium or thorium.
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 the appearance malignant tumors stomach and kidneys;

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

Ways to lower radon in water:
Boiling - when boiling, a significant amount of radon escapes, and it is necessary to organize an exhaust hood in the room where water is boiled. The use of activated carbon filters also reduces the concentration of radon.
Reduction of radon in the air: ventilation of the bathroom and kitchen, no smoking indoors. Smoking causes a risk of lung cancer 10 to 20 times that of non-smokers.

Nitrates and nitrites
They enter the human body with food and water, lead to 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 young children is especially dangerous, since prolonged oxygen starvation can cause a violation of the growth and formation of the body, retardation of physical and mental development, disorders of the cardiovascular system, promoting the development of cancer, congenital malformations. Nitrites are more toxic than nitrates.

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

Intensive 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, pollution of drinking water (and water in general - after all, you can drink all the water if it is clean) are given below:

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

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Are we always aware of what water means to us - this colorless, odorless and tasteless liquid? Scientists have long discovered a direct relationship between the quality of drinking water and human life expectancy. Have you ever wondered what kind of water you drink every day? Most of us, despite the warnings of doctors, prefer tap water - which has gone through several levels of purification and has come through the pipes to the faucet.
According to the laboratory of drinking water supply of the Research Institute of Human Ecology and environment RAMS, 90% of water supply networks supply water to homes that does not meet sanitary standards. The main reason for the presence of harmful nitrates, pesticides, oil products and salts of heavy metals in tap water is the catastrophic state of plumbing systems.
According to the State Sanitary and Epidemiological Supervision, the quality of drinking water is very low in Buryatia, in the Primorsky Territory, in the Arkhangelsk, Kaliningrad, Tomsk, Kemerovo, Kurgan, Yaroslavl regions.
With centralized water supply, it is legally determined that the water supplied to the consumer must be safe for health; it is understood that the content of harmful substances in water should not exceed the maximum permissible concentrations. Lead compounds remain one of the most important contributors to tap water pollution. The main source are water pipes and lead solder when connecting pipes. Although many countries have long banned the industrial production of pipes containing lead. In fact, manufacturers still use lead solder today. As a result of the use of these materials, lead appears in drinking water.
Lead has no taste or odor, and it can be determined whether it is present in drinking water by conducting a chemical analysis. Although, visually, you can do without it: looking at your water pipes, you yourself can easily determine whether you should be afraid for your health. If the pipes are gray in appearance and can be easily scratched with a sharp object, this is lead, and the natural corrosion that occurs in the plumbing will certainly lead to it getting into the drinking water. Lead-rich water can cause acute or chronic poisoning in humans.
In this regard, studies of the quality of tap water, which can have not only a positive but also a negative impact on people's health, are relevant. The topic seems interesting to us, because the water we drink has a great impact on health. And we wanted to be sure that domestic water would not harm the health of our families and friends.
There is a significant amount of literature on this topic. The most detailed material is presented on the requirements for the quality of drinking tap water and the effect of its composition on human health in the book of Itskova A.I. "Our way of life through the eyes of a doctor." A serious study on the problem of drinking water quality is reflected in the materials of Mikhail Akhmanov's book "The Water We Drink". The author pays special attention to methods of water purification at home, evaluates the effectiveness and usefulness of filters offered by domestic and foreign companies. While working on the book, the researcher collected information about the quality of drinking water in different regions of Russia and received advice from leading experts. We consider this material especially interesting and informative, we recommend it for reading to everyone who cares about their own health.

Novelty: Identification of the characteristics of lead content in tap drinking water on human health

Target: Study of the effect of lead in tap water on human health.

Tasks:
to find in sources of information and analyze data on the impact of lead content in tap water on human health;
having studied literary sources, choose a method for detecting lead in tap water, conduct a study;
conduct a survey of classmates and friends about the knowledge of the composition of drinking water and its impact on our health;
develop recommendations for improving water at home in accessible ways, inform friends and classmates.

Object of study: tap water from the water utility of the central district of the city of Kiselevsk.

Subject of study: lead content in tap water.

Hypothesis: Let us assume that the study of the effect of lead in tap water on health will be effective if we study modern literary and Internet sources devoted to this problem, select an accessible method for detecting lead in tap water for research, develop recommendations for improving water at home, and inform classmates.

Research methods: analysis of literary and informational sources, sociological survey, observation, analysis, experiment (study of the composition of drinking water according to selected methods), interviews, introspection.

Practical significance: The results of our activities will provide information on the state of the quality of tap water on the content of lead impurities. The materials and results of the work can be used in extracurricular activities on ecology, as well as to inform students and their parents.

Location of the study: Central district of Kiselevsk

Literature review
In the course of the research work, a review of the literature on the topic of the study was carried out, the impact of drinking water quality on health, drinking water quality standards were studied
We have found that lead compounds in tap water remain one of the most important factors harmful effects on human health. One of the main sources are old water pipes. Lead is a heavy metal that can accumulate in the human body and lead to severe poisoning, the maximum permissible value of which in water should not exceed 0.01 - 0.03 mg / l. In nature, lead occurs in the form of various compounds, the most important of which is the lead luster PbS. The prevalence of lead in the earth's crust is 0.0016 wt. %.
Lead is a bluish-white heavy metal with a density of 11.344 g/cm3. It is very soft and easy to cut with a knife. The melting point of lead is 327.3 °C. In air, lead is quickly covered with a thin layer of oxide, which protects it from further oxidation.
The Ministry of the Environment has set the maximum allowable level for lead in drinking water at 15 ppb.
It is especially dangerous for children. According to statistics, about 4 million children in the world suffer from the consequences of lead poisoning. Its toxic effect is associated with the suppression of hemoglobin reproduction and the deactivation of enzymes in the brain and nervous system. Depending on the concentration of lead in the body, this leads to pathology of varying severity.
Sources of lead (Pb) in tap water:
- old water pipes;
- lead contained in water pipe adapters
- lead solder joints for pipes;
- “soft” solders (the most famous is “tretnik” - an alloy of lead and tin) - a method of connecting pipes to each other;
- lead dissolved in natural water; lead contaminants entering natural water in various ways (eg gasoline);
The constant ingestion of small doses of lead into the body is dangerous, since this metal tends to accumulate in organs and tissues, causing chronic poisoning. There are practically no organs in which lead would not accumulate, but most of all it settles in the nails, hair and gums. Traces of poisoning begin to appear when the amount of lead exceeds 40-60 mg/100 ml. This affects the peripheral nervous system, liver and kidneys.
Lead has a detrimental effect on red blood cells, so prolonged use of water, even with small doses of lead, can lead to anemia over time, as red blood cells lose their ability to carry oxygen.
In addition, lead blocks the intake of vitamin D, which contributes to the accumulation of calcium in the bones. Lead-containing water is especially dangerous for young children and pregnant women. The latter may be at risk premature birth or malformations in the fetus.
For the detection of lead, we were looking for a technique based on a color reaction - qualitative analysis. The main selection criterion is that the technique is simple to perform and could be performed in a school laboratory.

Research methodology
Most modern homes have non-metallic pipes installed, but there are still many homes that have old pipes installed, which is the reason for the increase in lead levels in the water. The activities carried out in recent years by various structures have made it possible to significantly reduce the content of lead in water. But metal faucets and pipes connecting houses to the main water pipe, and home faucets sometimes still aggravate this problem. Water lingering in pipes and taps for several hours absorbs lead particles that are formed as a result of corrosion of the pipe itself or the seams on it.
There is no better way to determine the level of lead in your drinking water than by testing it. chemical composition.
Based on the literature data, the most convenient and optimal method for determining lead in tap water was chosen.
We used the methodology of laboratory work, which is available for conducting experiments in the school laboratory (the methodology is borrowed from foreign experience in teaching chemistry).
The proposed lead detection method is based on a color reaction that results in a lead iodide precipitate.
If the precipitate does not fall out and the water does not change color, then tap water does not contain lead in appreciable amounts. The sensitivity of the method is 0.1 mg in 5 ml of solution.
Evaluation of the results: water sediment is characterized: quantitatively - by the layer thickness; in relation to the volume of the water sample - negligible, insignificant, noticeable, large; qualitatively - by composition: amorphous, crystalline, flaky, silty, sandy.
Reagents and equipment:
- clean test tubes;
- a solution of potassium iodide;
- acetic acid;
- spirit stove or gas burner;
- ice or container with cold water;
- sulphuric acid;
- measuring cylinder with a capacity of 10 ml;
- milliliter glasses (glassware is washed with distilled water).

Operating procedure:
Purpose: Determination of lead content in samples of tap water from three sources of residential premises in the central district of the city, taking into account the installed water pipes. We examined water samples from three water supply sources: water was taken at MBOU SOSH No. 14, MBU DO CDT; residential building st. Unzhakova, 16. It is necessary to establish whether the water contains soluble lead compounds.
There is a very characteristic and highly sensitive reaction, which can rightly be called one of the most beautiful in chemistry. It is based on the ability of lead to interact with iodine, forming a poorly soluble compound PbI2.
Experienced part:
Progress:
1) pour water samples into numbered test tubes;
2) preparation of the reagent solution;
3) conducting the experiment.

Experience number 1. Determination of lead compounds in water using a solution of potassium iodide - KI.
1. Pour 10 ml of water sample from bottle No. 1 into a clean test tube made of refractory glass;
2. Added 1 ml of the reagent solution (potassium iodide solution - KI, acidified with a few drops of acetic acid, for a better reaction).3
3. Study of changes in the water sample. Shake the contents of the test tube. If the water contained soluble lead compounds, a yellow precipitate of lead iodide will form. He is unremarkable in appearance. But if you heat the test tube well on the flame of an alcohol lamp or gas burner (the precipitate should dissolve), and then quickly cool it, for example, by placing it in ice or a container with cold water, then the PbI2 precipitate will fall out again, only now in the form of beautiful golden crystals.

The water in test tube No. 1 slightly changed color, the color is light-light yellow, there is a noticeable slight turbidity, which indicates minor impurities of lead in the water, corresponding to MPC;

The water in test tube No. 3 did not change its qualities, turbidity, color change and sediment were not detected;

Experience number 2. Determination of lead compounds with sulfuric acid.
Add 10 ml of test water to the test tube, add 2-3 drops of sulfuric acid.
1. When interacting with the lead ion Pb ^ 2 +, a reaction of the type occurs: K2SO4 + Pb (NO3) 2 \u003d PbSO4 + 2KNO3.
2. The resulting lead sulfate precipitates as a dense white precipitate.
3. Control reaction.
It is worth noting that the precipitation of the same-looking precipitate is a characteristic reaction to barium ion. How can you be sure it's not barium sulfate? To do this, it is necessary to carry out a control reaction: add a strong alkali solution to the precipitate, and then heat the test tube. If it is lead sulfate, then the precipitate will gradually disappear due to the formation of a soluble complex salt. The reaction proceeds according to the following scheme: PbSO4 + 4NaOH = Na2 + Na2SO4. Barium sulfate in the same control test will remain as a precipitate.
The experiment was carried out with each of the tap water samples taken, upon completion, the following conclusions were made:
In the water from test tube No. 1, slight turbidity was noticed, no sediment was found;
The water in test tube No. 2 did not change its qualities, turbidity, color change and sediment were not detected;
The water in test tube No. 3 did not change its qualities, turbidity, color change and sediment were not detected.
Evaluation of the results: according to the nature of the precipitate and the color of the water, we determined the approximate content of lead ions: in the absence of sediment, the concentration of lead ions is less than 0.01 mg/l; with a slightly pronounced sediment, or a change in the color of the water that appears after a few minutes, up to 0.3 mg / l; a pronounced precipitate indicates a fairly high content of lead ions (more than 0.3 mg/l).
The maximum allowable concentration of lead in tap water should not exceed 0.01-0.03 mg/l.
Conclusion: Experience shows that during the observation of three tested water samples, the assumption was confirmed that tap water may contain lead impurities, it is positive that the detected impurities do not exceed the maximum allowable standards. Attention should be paid to the quality and material of the water pipes, where water was taken for test tube No. 1.

Results of interviews with specialists of JSC PO Vodokanal
To obtain detailed information about the existence of this problem in our city, we prepared for a conversation with specialists from the service that provides us with water. A list of questions was developed and interviews were conducted with the main specialists of the Kiselevsky Vodokanal:
Pavel Alexandrovich Saprykin - Deputy Director for Production of the Kiselev branch of OJSC PA Vodokanal and Gaivoronsky Viktor Viktorovich - Head of emergency and restoration work at OJSC PA Vodokanal.
Conclusion: From the answers of the experts, it became clear that this problem does not arise from the urban part of the pipes, which means that lead is emitted in the pipes in your home. The main source of lead in tap water is the destruction of lead-containing elements of water supply networks (solders, brass alloys).

Methodology and results of the survey
When performing research work, we conducted a survey among students in my class, followed by statistical processing and analysis of the data obtained. 22 people took part in the survey.
The order of the survey:
1. Development of questionnaires;
2. Testing, each of the respondents filled out the questionnaire on their own in order to avoid outside influence;
3.Processing and analysis of the obtained results.
Survey results:
In order to determine awareness of the safety of tap water and how to clean it, we developed questionnaire questions and conducted a survey of friends and classmates, as a result, we identified:
1.73% of the interviewed classmates use raw tap water;
2. Only 59% of students know which water pipes are installed in apartments;
3. 59% of respondents have suspicions about the quality and safety of the tap water they drink;
4. Do not know about impurities of heavy metals, harmful to health, which may be contained in tap water - 73% of respondents;
5. 95% of respondents know about methods of purifying tap water
6. The most popular methods of water purification in the families of classmates are filtration and boiling, 95% prefer boiling. The water settling method is not used.
Conclusion: More than 70% of respondents do not know what harmful impurities may be contained in tap water and effective ways water purification at home.

Article from the journal "Priroda" (No. 4, 2012, pp. 39-43, © Chetverikova A.V.)
Anna Vadimovna Chetverikova, post-graduate student of the Laboratory of Regional Hydrogeological Problems of the Institute of Water Problems of the Russian Academy of Sciences. The area of ​​scientific interests is the resources and quality of groundwater, their protection from pollution and artificial replenishment.

The problem of providing the population, industry and Agriculture water of the required quality today is very acute. Particular attention is paid to sources of fresh water. drinking water, namely groundwater. As a rule, unlike surface ones, they are of higher quality and better protected from pollution, and their characteristics are less subject to long-term and seasonal fluctuations. That is why groundwater is considered a priority sources of clean drinking water both in Russia and in the world. It would seem that it is advisable to use only them for domestic and drinking water supply. But, unfortunately, everything is not so simple. Underground sources of the required scale are often quite far from the consumer, and water must be transported over considerable distances. In addition, and most importantly, the anthropogenic pressure on groundwater is constantly increasing, which leads to a deterioration in their quality. The industry is developing - pollution is growing.

The quality of groundwater is determined by physical, chemical and sanitary-bacteriological indicators (in Russia, these indicators are regulated by the Sanitary and Epidemiological Rules and Regulations "Drinking Water. Hygienic Requirements for Water Quality of Centralized Drinking Water Supply Systems. Quality Control" (SanPiN 2.1.4.1074-01)) .

Chemical indicators characterize the chemical composition of water, which is normalized according to maximum allowable concentration(MPC). Under MPC is understood. Obviously, if the content of individual chemicals in water does not exceed the MPC, then such water is considered clean and can be drunk. As an example, let's consider the south of the European territory of Russia (the specific consumption of groundwater here is 122.92 l / day per person, while surface water is much less, only 94.40 l / day.).

For our (hereinafter - on behalf of the author of the article Chetverikova A.V.) research, the elements that are most dangerous from a sanitary and epidemiological point of view, as well as substances identified in groundwater in the largest amount, were selected - ammonia, ammonium, arsenic, general iron, oil products and metals second and third hazard classes. Metals of the second hazard class in groundwater of domestic drinking and cultural water use in the south of Russia are represented by barium, lead, strontium, cadmium, lithium and aluminum, and metals of the third class - manganese and nickel.

Schematic map of the excess of MPCs of metals II and III hazard classes in groundwater.

According to medical and environmental data, an increase in the concentrations of all these substances in water can lead to diseases of various severity.

Arsenic causes damage to the nervous system, skin and organs of vision, and in combination with other pollutants increases the risk of developing cancer.

Constant ingestion of water with a high content ammonium leads to chronic acidosis.

Iron causes irritation of the skin and mucous membranes, allergic reactions, and blood diseases. Oil products(due to the low molecular weight aliphatic, naphthenic and especially aromatic hydrocarbons included in their composition) have a toxic and to some extent narcotic effect on the body, affecting the cardiovascular and nervous systems.

Barium are classified as toxic ultramicroelements, but this element itself is not considered mutagenic or carcinogenic. Its compounds are toxic (with the exception of barium sulfate used in radiology). They negatively affect nervous, cardiovascular and circulatory systems.

Lead affects the blood-forming organs, kidneys, nervous system, causes cardiovascular diseases, beriberi C and B. An excess of lead in a woman's body can lead to infertility .

Strontium causes bone lesions(strontium rickets). This element accumulates at a high rate in the body of a child up to the age of four, during the period active formation bone tissue. The exchange of strontium changes at some diseases of the digestive system and the cardiovascular system.

Cadmium are classified as toxic (immunotoxic) elements. Many of its compounds are poisonous. A high concentration of cadmium in water leads to oncological and cardiovascular diseases, to lesions of the bone apparatus (itai-itai disease) and kidneys. Cadmium disturbs the course of pregnancy and childbirth.

Mechanism of toxic action lithium on the human body remains poorly understood. Perhaps lithium affects the maintenance mechanisms homeostasis of sodium, potassium, magnesium and calcium. Chronic exposure to lithium usually develops hyperkalemia and Na/K imbalance .

Toxicity aluminum manifests itself in metabolic disorders (especially mineral) of the functions of the nervous system, memory, motor activity. Some studies have linked aluminum to the brain lesions associated with Alzheimer's disease(at the same time, an increased content of aluminum is noted in the hair).

Nickel causes damage to the heart, liver, organs of vision (keratitis).

Manganese reduces nerve impulse conduction. As a result, fatigue increases, drowsiness occurs, reaction speed and performance decrease, dizziness, depressive and depressed states appear. Manganese poisoning is especially dangerous for children and pregnant women.
Schematic map of ammonium, ammonia and total iron excess in groundwater.

Let's try to figure out what quality of water the inhabitants of the south of the European territory of Russia drink. Schematic maps compiled according to the data of FGUGP "Gidrospetsgeologiya" for 2009 show the excess of MPC of various substances and elements in groundwater of the main exploited aquifer complex (i.e. several aquiferous "layers" from which groundwater is extracted) - Quaternary . The maps show both areal data and excess MPCs of substances and elements at individual points. It should be noted that the areas marked on the map of exceeding the MPC of boron, strontium, sulfates, chlorides and fluorine do not indicate an increased content of these elements throughout the territory, but only a high probability of detecting high concentrations of the substances in question in the designated area.

It is obvious that the excess of the MPC for ammonia, ammonium, arsenic, total iron, oil products, barium, lead, strontium, cadmium, lithium, aluminum, manganese and nickel is confined mainly to large cities and industrial centers, as well as to subsoil areas affected by economic activities. In general, no regional changes in the hydrogeochemical state of groundwater have been identified in the south of the European territory of Russia. Thus, we can talk not about areal, but only about point pollution of sources, which we will consider in more detail.

On the territory of the south of Russia, eight artesian basins(an artesian basin in hydrogeology is understood as an underground reservoir of fresh water, which differs in the conditions of their formation (feeding, accumulation, discharge), occurrence and distribution.). These include:

1. Azov-Kuban,
2. East Ciscaucasian,
3. Ergeninsky,
4. Privolzhsko-Khopersky,
5. Donetsk-Donskoy,
6. Caspian basins,
7. Donetsk hydrogeological folded area,
8. Caucasian hydrogeological folded region.

Azov-Kuban artesian basin located within the Krasnodar Territory, the southern part of the Rostov Region. and the western part of the Stavropol Territory. Underground sources here are contaminated with lithium, ammonium and its salts, common iron, oil products and manganese. An increased content of lithium was found at several water intakes in the Rostov region. (1.3-3.3) [hereinafter: the values ​​in parentheses are in fractions of MPC] and in the city of Novocherkassk (7.3). The content of ammonium and its salts in the water intakes of the Krasnodar, Leningrad and Krasnogvardeyskoye groundwater deposits (GWB) varies from 1.1 to 2.8 MPC, and in the Azov district of the Rostov region. - from 2.6 to 33.1 MPC. The content of total iron is exceeded at the water intakes of the Krasnodar IWW (1.3-7.5) and in the Rostov region. (2.3-8.3), oil products - in the Seversky (1.2) and Dinskoy (up to 10) districts of the Krasnodar Territory and in the city of Novocherkassk (6.6). The concentration of manganese is higher than the permissible one at the water intakes of the Krasnodar MPV (1.1-7.2), in the city of Novocherkassk (8.7), as well as in the Krymsky (8.7) and Seversky (13) districts of the Krasnodar Territory.
Schematic map of excess MPC of oil products in groundwater.

In the Rostov region pollution is mainly caused sewage and closeness sludge collectors. In the Krasnodar Territory, it is due to the inflow into underground sources substandard waters. In addition, water quality is adversely affected by the proximity federal highway M-4 and extensive agricultural fields.

East Ciscaucasian artesian basin includes the territory of the Stavropol Territory and the republics of Dagestan, Kabardino-Balkaria, North Ossetia-Alania, Ingushetia, Chechnya and Kalmykia. Underground sources in a significant part of the basin are contaminated with arsenic. It was found at the water intakes of the Neftekumsk MPV (10.1), the settlement of Zimnyaya Stavka (6-10), on the territory of the Stavropol Territory (up to 2), as well as in a number of districts of the Republic of Dagestan (2.3-17.7). In Dagestan, an increased content of cadmium (up to 3) and manganese (1.1) was also recorded. Nickel was found in water in Stavropol (2). The water intakes of the Derbent WSS (81), the city of Pyatigorsk (17.8) and the city of Mozdok (49.6) are polluted with oil products. A significant excess of the permissible ammonium content was found mainly in the cities of Nalchik (666), Stavropol (39.9), Budennovsk (5.65), Pyatigorsk (5.25), Ardon (4) and Beslan (1.3), as well as at the water intakes of Severo-Levokumsky and Neftekumsky MPV of the Stavropol Territory.

This pollution is caused by the influence of mine dumps, adits and sludge reservoirs, leaks from the sewer and underground pipelines, as well as sewage. The increased content of ammonium in water, on the one hand, is explained by the anthropogenic load on drinking sources, and on the other hand, it is typical for groundwater in the eastern part of the Stavropol Territory and is considered background here.

In the territory Ergeninsky artesian basin(Rostov, Volgograd and Astrakhan regions and the Republic of Kalmykia), on the Kurgan farm, Orlovsky district, Rostov region. revealed water pollution with nickel (164), total iron (26), ammonium (4.1), lithium (2.3) and oil products (1.3).

The groundwater Donetsk folded region located on the territory of the Rostov region are contaminated with lithium (from 1.7 to 3) and manganese (1.5-3.2). Here they experience a significant burden from substandard deep mine waters, which enter underground sources as a result of the liquidation of old mines by flooding them.

Privolzhsko-Khopersky artesian basin is located on the territory of the Rostov and Volgograd regions, extending to the west into the Voronezh region, and to the north - to the Saratov region. Here, an increased content of total iron in the water (1.7-24.7) was revealed.

In the territory Donetsk-Don artesian basin(Rostov and Volgograd regions) increased concentrations of lithium - at the water intakes of Malokamensky-II (2.7), Donetsk (4.3) and Millerovsky (2) of the Rostov region. The content of oil products exceeds the allowable at Borodinovsky (1.4) and Donetsk (3.9), and total iron - at the Donetsk and Millerovsky water intakes of the Rostov region. (2.6-6), as well as in the Volgograd region. (5.7-13.6). However, the increased iron content here may be due to with severe deterioration of pipes of observation wells .

In water Caspian artesian basin(Republic of Kalmykia, Volgograd and Astrakhan regions) found a number of pollutants. Cadmium (3-8.6) and aluminum (1.7-9) were noted in the Volgograd region, lead (2.7-5) - in the settlements of the Akhtubinsky mountain of the Astrakhan region, barium (1.4-3.9) - in the Akhtubinsky and Kharabalinsky districts. Also in the Astrakhan region. found lithium (1.3-2.2). Manganese polluted the water of the Volgograd and Astrakhan regions (2.8-243), nickel (2.5-3) was noted in the village of Trudolyubie and the village of Svetly Yar, Volgograd region. Ammonium and ammonia are present in the water intakes of the cities of Pallasovka and Volzhsky, Volgograd oblast. (1.1-66.2) and in the Akhtubinsky and Krasnoyarsk districts of the Astrakhan region. (0.1-149.1). The content of iron is increased in the water intakes of the largest cities of the Volgograd (14-1426.7) and Astrakhan (1.5-467.3) regions, and oil products - in the village of Svetly Yar (2.5) and the village of Bolshie Chapurniki (41) of the Volgograd region. and the village of Ashuluk, Astrakhan region. (0.3-4.3).

Here, the sources of pollution are the storage ponds and evaporation ponds of the Volgograd CHPP, the ash dump of the Astrakhan State District Power Plant, the Akhtubinskaya oil depot, military landfills, housing and communal services filtration fields, a sewage injection landfill and an industrial waste dump.

Caucasian hydrogeological folded region located on the territory of the Krasnodar Territory and the republics of Karachay-Cherkessia, Kabardino-Balkaria, North Ossetia - Alania and Adygea. This area is polluted mainly with oil products. They enter underground sources due to the unsatisfactory condition of tanks, pumping stations, wells, industrial sewage, oil traps and oil pipelines, as well as as a result of losses when filling containers and on overpasses when draining oil products.

Thus, in the immediate vicinity of industrial facilities, gold dumps, military ranges, landfills, etc. groundwater does not meet the required standards. This water cannot be used for drinking purposes.. Groundwater pollution can be reduced by special water treatment (purification), which today there are a large number of methods. Among them are aeration, sedimentation, rapid filtration, pre-filtration, chlorination and many others. Of course, all of them imply additional economic costs. But clean drinking water is worth it, because it is the key to public health.

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