Water is the source of life on Earth, a great natural value that covers 71% of the surface of our planet, the most common chemical compound and the necessary basis for the existence of all life on the planet. The high content in plants (up to 90%) and in the human body (about 70%) only confirms the importance of this component, which has no taste, smell or color.
Water is life!
The role of water in human life is invaluable: it is used for drinking, food, washing, various household and industrial needs. Water is life!
The role of water in human life can be determined by its share in the body and organs, each cell of which is rich in an aqueous solution of essential nutrients. Water is one of the effective means of physical education, widely used for personal hygiene, recreational physical education, hardening, and water sports.
Biochemical properties of water
Preservation of the elasticity and volume of a living cell would be impossible without water, as well as a significant part of the chemical reactions of the body that occur precisely in aqueous solutions. Such a valuable liquid is indispensable for its thermal conductivity and heat capacity, which provides thermoregulation and protects against temperature extremes.
Water in human life is able to dissolve some acids, bases and salts, which are ionic compounds and some polar non-ionic formations (simple alcohols, amino acids, sugars), called hydrophilic (from Greek literally - a tendency to moisture). Nucleic acids, fats, proteins and some polysaccharides are hydrophobic substances (from Greek - fear of moisture) beyond the power of liquid.
The biological significance of water is quite large, since this priceless liquid is the main medium for internal processes occurring in the body. In percentage terms, the presence of water in the body is as follows:
Body systems | |
Adipose tissue | |
The statement of the science fiction writer V. Savchenko, who revealed the meaning of water in one phrase, is interesting on this occasion: a person has much more motives to consider himself a liquid, in contrast, for example, to a 40% sodium solution. And among biologists, a joke is popular that water “invented” a person as a means of its own transportation, the main component of whose body it is. 2/3 of its total amount is contained inside the cells and is called "intracellular" or "structured" fluid, which is capable of providing the body's resistance to the influence of negative environmental factors. The third part of the water is outside the cells, and 20% of this amount is the intercellular fluid itself, 2% and 8% - respectively, the water of the lymph and blood plasma.
Importance of water in human life
The value of the natural component in life and everyday life is simply invaluable, since without it existence is impossible in principle.
Water is essential for life because:
- humidifies the inhaled oxygen;
- helps the body in the qualitative assimilation of nutrients;
- contributes to the conversion of food into energy and normal digestion;
- participates in passing metabolism and chemical reactions;
- removes excess salts, toxins and toxins;
- regulates body temperature;
- provides skin elasticity;
- regulates blood pressure;
- prevents the formation of kidney stones;
- is a kind of "lubricant" for the joints and a shock absorber for the spinal cord;
- protects vital organs.
The water cycle in the body
One of the conditions for the existence of all living things is the constant content of water, the amount of which enters the body depends on the lifestyle of a person, his age, physical health, and environmental factors. During the day, up to 6% of the water available in the body is exchanged; half of its total amount is updated within 10 days. So, per day the body loses about 150 ml of water with feces, about 500 ml with exhaled air and the same amount with sweat and 1.5 liters is excreted in the urine. Approximately the same amount of water (about 3 liters per day) a person receives back. Of these, a third of a liter is formed in the body itself during biochemical processes, and about 2 liters are consumed with food and drinks, and the daily need for exclusively drinking water is about 1.5 liters.
Recently, experts have calculated that a person should still drink about 2 liters of pure water a day in order to prevent even the slightest dehydration of the body. The same amount is recommended to be consumed by yogis who know the true meaning of air and water. An absolutely healthy human body should ideally have a state of water balance, otherwise called water balance.
By the way, German scientists, after a series of experiments conducted on students, found out that those who drink water and drinks more than others show greater restraint and a penchant for creativity. Water in human life plays an incentive role, filling with energy and vitality.
According to some estimates, for 60 years of life a person on average drinks about 50 tons of water, which is commensurate with almost a whole tank. It is interesting to know that ordinary food is half water: in its meat - up to 67%, in cereals - 80%, vegetables and fruits contain up to 90%, bread - about 50%.
High Water Consumption Situations
Usually a person receives about 2-3 liters of water per day, but there are situations in which the need for it increases. This:
- Increased body temperature (more than 37 ° C). With each increasing degree of water, 10% more of the total is required. .
- Heavy physical work in the fresh air, in which you need to drink 5-6 liters of liquid.
- Work in hot shops - up to 15 liters.
Deficiency of valuable fluid is the cause of many diseases: allergies, asthma, overweight, high blood pressure, emotional problems (including depression), and its absence leads to disruption of all body functions, undermining health and making vulnerable to diseases.
Loss of water up to 2% of the total body weight (1 - 1.5 liters) will cause a person to feel thirsty; loss of 6 - 8% will lead to a semi-conscious state; 10% will cause the appearance of hallucinations and impaired swallowing function. Deprivation of 12% of water from the total body weight will lead to death. If without food a person is able to survive for about 50 days, subject to the consumption of drinking water, then without it - a maximum of 5 days.
In fact, most people drink less than the recommended amount of water: only a third, and the ailments that appear are not at all associated with a lack of fluid.
Signs of lack of water in the body
The first signs of dehydration:
A stable intake of water in the body in the required amount helps to ensure vitality, get rid of ailments and many serious diseases, improve thinking and coordination of the brain. Therefore, the emerging thirst should always be tried to quench. It is better to drink little and often at the same time, since a large amount of liquid for the purpose of a one-time replenishment of the daily norm will be completely absorbed into the blood, which will give a noticeable load on the heart until the water is removed from the body by the kidneys.
Water balance of the body - a direct path to health
In other words, water in human life, with a properly organized drinking regime, can create acceptable conditions for maintaining the necessary water balance. It is important that the liquid is of high quality, with the presence of the necessary minerals. The situation of the modern world is paradoxical: water, the source of life on Earth, can be dangerous for life itself, carrying various infections with almost every drop. That is, only pure water can be useful for the body, the problem of the quality of which is very relevant in the modern world.
Water scarcity is a scary future for the planet
Rather, the very problem of the availability of drinking water becomes vitally important, every day turning into an increasingly scarce product. Moreover, the importance of water on Earth and its lack in international relations are discussed at the highest level and often in a conflicting way.
Now more than 40 countries are experiencing water shortages due to the aridity of many regions. In 15 - 20 years, even according to the most optimistic forecasts, every person will understand the importance of water on Earth, since the problem of its shortage will affect 60 - 70% of the planet's population. In developing countries, water deficit will increase by 50%, in developed countries - by 18%. As a result, international tension around the topic of water scarcity will increase.
Polluted water as a result of human activity
This is due to geophysical conditions, human economic activity, often ill-conceived and irresponsible, which significantly increases the burden on water resources and leads to their pollution. A huge amount of water goes to the needs of cities and industry, which not only consume, but also pollute water, dumping about 2 million tons of waste into water bodies every day. The same goes for agriculture, where millions of tons of waste products and fertilizers flow into waterways from farms and fields. In Europe, out of 55 rivers, only 5 are considered clean, while in Asia, all rivers are extremely littered with agricultural waste and metals. In China, 550 out of 600 cities are experiencing water shortages; due to severe pollution, fish do not survive in water bodies, and some rivers that flow into the ocean simply do not reach it.
What flows from the taps
And why go far if the quality of water, which leaves much to be desired, concerns almost every person. The importance of water in human life is great, this is especially true when it is consumed, when sanitary standards go against the quality of the consumed liquid, which contains pesticides, nitrites, oil products, heavy metal salts that are harmful to health. Half of the population receives hazardous water, which causes about 80% of all known diseases.
Chlorine is dangerous!
To avoid possible infection with any infection, the water is chlorinated, which in no way diminishes the danger. On the contrary, chlorine, which destroys many dangerous microbes, forms chemical compounds that are harmful to health and provokes diseases such as gastritis, pneumonia, and oncology. When boiling, it does not have time to dissolve completely and combines with organic substances always present in water. In this case, dioxins are formed - very dangerous poisons, surpassing even potassium cyanide in their strength.
Water poisoning is much worse than food poisoning, because water in human life, unlike food, takes part in all biochemical processes of the body. Dioxins accumulated in the body decompose very slowly, almost tens of years. Causing disorders of the endocrine system, reproductive functions, they destroy the immune system, cause cancer and genetic abnormalities. Chlorine is the most dangerous killer of our time: killing one disease, it gives rise to another, even worse. After global water chlorination began in 1944, epidemics of heart disease, dementia and cancer began to appear massively. The risk of cancer is 93% greater than that of those who drink non-chlorinated water. There is only one conclusion: tap water should never be drunk. The ecological significance of water is the No. 1 problem in the world, since if there is no water, there will be no life on Earth. Therefore, an indispensable condition for maintaining health is its cleaning and compliance with sanitary and epidemiological standards.
Water itself has no nutritional value, but it is an indispensable component of all living things. None of the living organisms on our planet can exist without water.
All living plant and animal beings are composed of water:
fish - by 75%; jellyfish - by 99%; potatoes - by 76%; apples - by 85%; tomatoes - by 90%; cucumbers - by 95%; watermelons - by 96%.
In general, the human body consists of 50-86% by weight of water (86% in a newborn and up to 50% in the elderly). The water content in various parts of the body is: bones - 20-30%; liver - up to 69%; muscles - up to 70%; brain - up to 75%; kidneys - up to 82%; blood - up to 85%.
This circumstance allowed the science fiction writer V. Savchenko to declare that a person “has much more reason to consider himself a liquid than, say, a forty percent solution of caustic sodium.”
Throughout his life, a person daily deals with water. He uses it for drinking and food, for washing, in summer for rest, in winter for heating.
For a person, water is a more valuable natural resource than coal, oil, gas, iron, because it is irreplaceable.
A person can live without food for about 50 days, if during a hunger strike he drinks fresh water, he will not live without water for a week - death will occur in 5 days. According to medical experiments, with a loss of moisture in the amount of 6-8% of body weight, a person falls into a semi-conscious state, with a loss of 10%, hallucinations begin, with 12%, a person cannot recover without special medical care, and with a loss of 20%, inevitable death occurs. .
In the human body, water:
- humidifies oxygen for breathing;
- regulates body temperature;
- helps the body absorb nutrients;
- protects vital organs;
- lubricates the joints;
- helps convert food into energy;
- participates in metabolism;
- removes various waste products from the body.
A person begins to feel thirsty when the amount of water in his body decreases by 1-2% (0.5-1.0l). Loss of 10% of moisture from body weight can lead to irreversible changes in the body, and the loss of 20% (7 - 8l) is already fatal.
The average person loses 2-3 liters of water per day. In hot weather, with high humidity, during sports, water consumption increases. Even through breathing, a person loses almost half a liter of water daily.
The correct drinking regime implies the preservation of the physiological water balance - this is a balancing of the inflow and formation of water with its release.
The daily requirement of an adult in water is 30-40 grams per 1 kg of body weight. Approximately 40% of the body's daily water requirement is met with food, the rest we must take in the form of various drinks. In summer, you need to drink 2 - 2.5 liters of water daily. In hot regions of the planet - 3.5 - 5.0 liters per day, and at an air temperature of 38-40C and low humidity, outdoor workers will need 6.0 - 6.5 liters of water per day. At the same time, you can’t focus on whether you are thirsty or not, since this reflex occurs already late and is not an adequate indicator of how much water your body needs.
It is interesting to know that cereals contain up to 80% water, bread - about 50%, meat - 58-67%, vegetables and fruits - up to 90% water, i.e. “Dry” food consists of 50-60% water.
And about 3% (0.3 l) of water is formed as a result of biochemical processes in the body itself.
According to some estimates, for 60 years of life a person drinks about 50 tons of water - a whole tank!
By participating in the metabolism, water can reduce fat accumulation and reduce weight. Many of those who want to lose weight believe that their body retains water and try to drink less of it. However, water is a natural diuretic and if you drink it, you will lose weight.
If the body receives enough water, then the person becomes more energetic and hardy. It is easier for him to control his weight, as digestion improves, and when you are drawn to a snack, it is often enough just to drink water to reduce your appetite. Symptoms of dehydration are dry skin (may be itchy), fatigue, poor concentration, headaches, high blood pressure, poor kidney function, dry cough, back and joint pain.
Research scientists have already proven that drinking enough water can minimize back pain, migraines, rheumatic pains, as well as lowering blood cholesterol and blood pressure, thereby reducing the likelihood of a heart attack. Drinking enough water is one of the best ways to prevent kidney stones. Since water does not contain salts, fat, cholesterol and caffeine, then, accordingly, it is excreted from the body in a different way.
German scientists, after conducting tests on student volunteers, came to the conclusion that those who drink more water and drinks show more endurance and a penchant for creativity than those who drink less.
Regular water intake improves thinking and brain coordination. The brain and the whole body will be sufficiently charged with the necessary substances if the water we drink is of high quality, that is, rich in minerals. A healthy person should not limit himself to drinking, but it is much more beneficial to drink little and often. It is harmful to drink a lot of liquid at once, since all the liquid is absorbed into the blood, and until its excess is excreted from the body by the kidneys, the heart receives an excessive load.
Thus, we can conclude that the role of water for humans is enormous. Today, each person can create for himself the conditions for maintaining an invaluable water balance through the proper organization of the drinking regime.
The role of water in human life undeniably high. It serves as the basis for the good functioning of the whole organism. In water there are various substances, the nature of the origin of which is diverse, both organic and inorganic.
It is almost three-quarters of the weight of an adult. Some of it, since it is inside the cells of the body, is called the intracellular fluid.
10. Hard.
It contains magnesium and potassium salts. This type negatively affects the functioning of the whole organism. It is deposited in the joints of a person. Here is an easy way to determine the level of hardness. You need to see how soap foams in it and whether there is a precipitate during boiling.
If these signs are found, it can be argued that the rigidity is increased. To reduce it, water must be boiled. Simply boiled is “dead” water. It will be useful to add berries (lingonberries, cranberries) to cooled boiled water. Good for the body will be infusions of wild rose and black currant.
Home water filters are the main way to improve its quality. It is worth paying attention to the filters, where silver is used as a purification element. For some it is contraindicated. You need to drink liquid before any meal, but in small quantities (2-3) sips.
Summing up all the above, it can be noted that the role of water in human life hard to overestimate. It delivers oxygen to cells, carries nutrients, normalizes temperature, is a lubricant for joints, and performs a number of other useful functions.
Water is an amazing liquid. It has no color, no taste, no smell. The calorie content of water is zero. Some people call it a real mystery. Water combines both simplicity and complexity in an amazing way. It would seem that there are only three atoms in a water molecule - one oxygen, and two hydrogens. However, scientists are still not completely clear on how these molecules work. But one thing is certain: if there is no water, there will be no life on Earth.
Water plays a huge role in human life. Without it, neither people, nor plants, nor animals can live. Neither a huge elephant, nor microscopic bacteria can do without this life-giving fluid. Every living organism is about 80% water. Without it, crops will not grow in the fields, and, accordingly, there will be no food. So, it is quite obvious: without water, life on the planet would quickly cease, and we would have nothing to replace it with.
But, to our happiness, water on our planet is contained in abundance. If you look at pictures taken from space, you can see that the predominant color of our planet is blue. And this is because its surface, like the atmosphere, contains a lot of water. Some even believe that with such water reserves, our planet should not be called Earth, but Water. And there is some truth in this. Think about it: the area of the Pacific Ocean alone is much larger than the area of all the earth's land masses put together!
Most of the water on Earth is in the oceans and seas. But, as you know, sea water contains a large amount of salt. If a person drank only sea water, then he would quickly die of thirst and dehydration, since the body is not able to cope with excessive amounts of salt. Sea water is also unsuitable for agriculture - it will simply destroy the crop. You can’t use it in industry either, since any mechanism will rust from salt water. Therefore, although there is a lot of sea water on Earth, there is practically nowhere to use it, except to make it fresh, but it is very expensive.
Only fresh water is truly valuable for human life. But we do not have so much of it - only 3% of the total volume of all water on the planet. And basically all fresh water (99%) is concentrated in glaciers, on mountain peaks and flows in the depths of the earth. It turns out that humanity has only one percent of all fresh water reserves.
Is it a lot or a little? Here is what the scientific journal People & the Planet wrote on this issue: “This amount, assuming an even distribution, is two and even three times more than enough for today's population of the earth.”
Amazing properties of water
Unlike other liquids, water has amazing properties. Below are five interesting facts about water.1. Even having absorbed a little solar energy, the waters of the oceans are able to retain a lot of heat. This useful property of water contributes to climate mitigation.
2. At low temperatures, water does not shrink like other substances, but expands, turning into ice. This serves as protection for the living organisms of the oceans. If water became denser when freezing, then all the waters of the Earth would freeze from the bottom to the surface. All living things would simply die.
3. Unlike other liquids, water is very transparent. Thanks to this property, the deep-sea inhabitants of the seas and oceans can receive a sufficient amount of sunlight, which penetrates through the water column precisely due to its transparency.
4. Not everyone knows that the surface of the water is covered with an invisible elastic film. This is due to the amazing properties of water molecules - they form surface tension. That is why insects can "walk" on the surface of reservoirs, and the water itself is able to rise up through the capillaries of trees, even reaching the tops!
5. The best solvent in the world is water. It dissolves oxygen, various salts, minerals and carbon dioxide.
The role of water in human life
The role of water in human life can be judged by a simple example - the man himself is mostly water. The human brain contains 75 - 85% water, and muscle tissue - approximately 70%. Water helps to ensure that the food we eat is quickly digested and absorbed by the body.The important role of water in nature and human life is reduced to the removal of toxins and other waste from the human and animal body. Water serves as a lubricant for our joints and regulates and maintains our body temperature.
Do you know that for a person who plans to lose weight, water will be of great importance in life, as it will help to reduce excess weight.
The fact is that water does not contain calories. What's more, it contains no fat, no cholesterol, and virtually no sodium. If you drink water regularly, it reduces your appetite. Also, water helps the process of processing fat in the body. If during the day you drink little water, then the kidneys become unable to function as expected. In this regard, the liver begins to take over part of the work that the kidneys should do, and this reduces its ability to process fats. Thus, fat begins to accumulate in the body, in other words, a person begins to become overweight. Many doctors have long recognized the fact that sufficient water intake is simply necessary in the fight against excess weight. If those who strive to lose weight neglect water, then the body is simply not able to process all the fat and the desired effect can simply not be achieved.
Therefore, try never to deprive your body of water. About two liters of this fluid are excreted from our body every day. Moisture is excreted through the skin, intestines, and also the lungs. It is noteworthy that when a person breathes, when exhaling, about half a liter of water is lost per day. Therefore, it is vitally important to replenish water reserves in the body.
The importance of water in life and the human body is enormous, in case of its lack, dehydration appears. Here are some signs of dehydration: fatigue, muscle and headache, unnaturally dark urine, dry mouth and eyes. Often in hot weather, many people lose consciousness and need medical attention due to dehydration.
How much water should you drink to keep your body healthy?
Of course, everyone has different circumstances, and people live in different climatic conditions. Therefore, there is no single rule, but on average a person should drink two to three liters of water per day. If you calculate approximately, then in a lifetime a person drinks from 50,000 to 70,000 liters of water. Do not assume that you should drink water only when you experience dry mouth. Many experts will tell you that if you feel thirsty, then dehydration of the body has already begun.Try to carry a bottle of water with you at all times.
Drink one glass of water during breakfast, lunch or dinner.
Drink water before, after and during exercise.
In between work it is better to drink water than coffee.
Is it possible to replace water with various drinks
Indeed, vegetable or fruit juices are able to replenish the body's reserves with the necessary moisture. But the same cannot be said for other drinks. So sweet carbonated drinks only contribute to dehydration, and alcohol, tea or coffee have a diuretic effect. Therefore, after the above drinks, you still need to replenish your body with water. Yes, nothing can replace this valuable liquid for us! And even if it has no taste, color and smell, nevertheless, water has always been and will be a vital substance in the life of every person.Water is the most important component of our habitat. After air, water is the second most important component necessary for human life.
How important water is is evidenced by the fact that its content in various organs is 70 - 90%. With age, the amount of water in
the body is changing. A three-month-old fetus contains 90% water, a newborn 80%, an adult - 70%. Water is present in all tissues of our body, although it is unevenly distributed:
The brain contains - 75%
Heart - 75%
Lungs - 85%
Liver - 86%
Kidneys - 83%
Muscles - 75%
Blood - 83%.
Today, more than ever, it is very important for our body to receive clean water with a balanced mineral composition. It carries our body's waste, delivers lubrication to our joints, stabilizes our temperature, and is the lifeblood of the cell.
Water is necessary to maintain all metabolic processes, it takes part in the absorption of nutrients by cells. Digestion becomes possible only when food becomes water-soluble. Crushed tiny food particles gain the ability to penetrate through the intestinal tissue into the blood and intracellular fluid. More than 85% of all metabolic processes in our body occur in the aquatic environment, so the lack of clean water inevitably leads to the formation of free radicals in human blood, which leads to premature skin aging and, as a result, the formation of wrinkles.
Consumption of clean water ensures the normal functioning of internal organs. It keeps your body flexible, lubricates your joints and aids in the absorption of nutrients. A good supply of clean water to the body helps fight excess weight. This is expressed not only in a decrease in excessive appetite, but also in the fact that a sufficient amount of pure water contributes to the processing of already accumulated fat. These fat cells, with the help of a good water balance, become able to leave your body.
Water is a heat carrier and thermostat. It absorbs excess heat and removes it by evaporating through the skin and respiratory tract. Water moisturizes the mucous membranes and the eyeball. In the heat and during physical exercises, intensive evaporation of water from the surface of the body occurs. Consumption of cool clean water, which is absorbed into the blood from the stomach, provides timely cooling of your body, protecting it from overheating. During training, for the normal functioning of the body, it is necessary to drink in small portions of about 1 liter per hour. Even if you do not bother yourself with physical exercises, you still need to constantly replenish the lack of water. The atmosphere in modern buildings is often overheated and air-conditioned. This dries the air and dehydrates the body. The same thing happens when traveling by train, plane and car. Coffee, tea, alcohol - all these joys of life contribute to the removal of water from the body. An adult is able to live without food for more than a month, without water for several days. Dehydration of the body by 10% leads to physical and mental incapacity. Loss of 20% of water leads to death. During the day, from 3 to 6% of the water contained in the body is exchanged. Half of the water contained in the body is exchanged within 10 days.
The amount of water required to maintain water balance depends on age, physical activity, ambient temperature and humidity.
The daily requirement of an adult is about 2.5 liters.
Clean drinking water also increases the body's defense against stress. It thins the blood, fights fatigue, helps the cardiovascular system, fights stress. A healthy lifestyle is based on proper nutrition, activity and the consumption of clean water.
With such a great importance of water for a person, the water must be of the appropriate quality, but if the water contains any harmful substances, they will inevitably be distributed throughout the body.
Impact of water resources on human health
The water we consume must be clean. Diseases transmitted through contaminated water cause ill health, disability and death in large numbers of people, especially children, predominantly in less developed countries where poor personal and communal hygiene is common. Diseases such as typhoid fever, dysentery, cholera, hookworm are transmitted primarily to humans as a result of contamination of water sources with excrement excreted from the body of patients.
Success in the fight against these diseases or the achievement of their complete elimination depends on how the system for removing all metabolic products excreted from the human body is organized, how the matter of providing clean water to the entire population is set.
The quality of water is also determined by the presence of chemical inclusions in it, which are the first to be detected by our senses: smell, sight.
So, microparticles of copper give the water some turbidity, iron - redness.
There are basic indicators of drinking water quality. They can be conditionally divided into groups:
1. Organoleptic indicators (smell, taste, color, turbidity)
2. Toxicological indicators (aluminum, lead, arsenic, phenols, pesticides)
3. Indicators affecting the organoleptic properties of water (pH, total hardness, petroleum products, iron, manganese, nitrates, calcium, magnesium, permanganate oxidizability, sulfides)
4. Chemicals generated during water treatment (residual free chlorine, chloroform, silver)
5. Microbiological indicators (thermotolerant coliforms or E. coli, TMC).
The experience of the laboratory for the analysis of water quality has shown that the most common water pollutants (the content of components exceeds the standards) include iron, manganese, sulfides, fluorides, calcium and magnesium salts, organic compounds, etc. What negative properties can be given to water by certain or other components in case of their content above the standards?
The presence of iron in water does not threaten our health. However, an increased content of iron in water (more than 0.3 mg/l) in the form of bicarbonates, sulfates, chlorides, organic complex compounds or in the form of a highly dispersed suspension gives the water an unpleasant red-brown color, worsens its taste, causes the development of iron bacteria, sedimentation in pipes and clogging. If you wash clothes in such water, rusty spots will remain on it. Similar stains appear on dishes, sinks and bathtubs.
When drinking water with an iron content above the norm, a person runs the risk of acquiring various liver diseases, allergic reactions, etc.
The increased content of manganese in water has a mutagenic effect on humans. At levels in the water supply that exceed 0.1 mg/L, manganese causes stains on plumbing fixtures and linen, and bad taste in drinks. The presence of manganese in drinking water can cause deposits to build up in the distribution system. Even at a concentration of 0.02 mg/l, manganese often forms a film on pipes, which flakes off as a black deposit.
Sometimes in drinking water there are many salts of hydrochloric and sulfuric acids (chlorides and sulfates). They give the water a salty and bitter-salty taste.
The use of such water leads to disruption of the gastrointestinal tract. Water, in 1 liter of which there are more than 350 mg of chlorides and more than 500 mg of sulfates, is considered unfavorable for health.
The content of calcium and magnesium cations in the water imparts the so-called hardness to the water. Water hardness is expressed in mg-eq / l (= mol / m3), in German degrees (1 mol / m3 = 2.804 German degrees), French degrees (1 mol / m3 = 5.005 French degrees), American degrees (1 mol / m3 = 50.050 US degrees). The optimal physiological level of hardness is 3.0-3.5 mg-eq/l.
Water highly saturated with salts causes a lot of inconvenience: vegetables and meat are more difficult to boil in it, soap consumption increases during washing, scale spoils teapots and boilers. Hardness above 4.5 mg-eq/l leads to intensive accumulation of sediment in the water supply system and plumbing, interferes with the operation of household appliances. According to the operating instructions for household appliances, water hardness should not exceed 1.5-2.0 mg-eq / l. Constant ingestion of water with increased hardness leads to the accumulation of salts in the body and, ultimately, to diseases of the joints (arthritis, polyarthritis), to the formation of stones in the kidneys, gall bladder and bladder.
Water is also responsible for human teeth. The incidence of caries depends on how much fluorine is contained in the water. Water fluoridation is believed to be effective in preventing caries, especially in children. The content of fluorides in drinking water above sanitary standards (not more than 1.5 mg/l) has a harmful effect on human health. Fluorine is a biologically active trace element, the content of which in drinking water should be in the range of 0.7-1.5 mg/l in order to avoid caries or dental fluorosis.
But in addition to useful impurities in the water, there are others that are dangerous to the human body.
The presence of sulfides (hydrogen sulfide) in water gives the water an unpleasant odor, intensifies the process of corrosion of pipelines and causes their overgrowth due to the development of sulfur bacteria. Sulfides have a toxic effect on humans and cause skin irritation. Hydrogen sulfide is poisonous to living organisms.
According to domestic researchers, the use of mine water containing 0.2-1 mg / l of arsenic causes a disorder of the central, and especially peripheral, nervous system, followed by the development of polyneuritis. Arsenic concentration of 0.05 mg/l was recognized as harmless.
Hygienists first spoke about the health hazards of lead in water in connection with mass intoxications that arose when lead pipes were used on water pipes. However, elevated concentrations of lead can occur in groundwater. Water is considered harmless if the lead content in it is not more than 0.03 mg/l.
Strontium is widely distributed in natural waters, while its concentrations vary widely (from 0.1 to 45 mg/l). Its long-term intake in large quantities in the body leads to functional changes in the liver. At the same time, prolonged use of drinking water containing strontium at a level of 7 mg/l does not cause functional and morphological changes in tissues, organs and in the whole human body. This value is accepted as a standard for the content of strontium for drinking water.
According to modern scientific data, nitrates in the human intestine are reduced to nitrites under the influence of bacteria living there. The absorption of nitrates leads to the formation of methemoglobin and to a partial loss of hemoglobin activity in oxygen transport.
Thus, methemoglobinemia is based on one or another degree of oxygen starvation, the symptoms of which are manifested primarily in children, especially infants. They get sick mainly during artificial feeding, when dry milk formulas are diluted with water containing nitrates, or when this water is used for drinking. Older children are less susceptible to this disease, and if they get sick, it is less severe, since they have more developed compensatory mechanisms. The use of water containing 2–11 mg/l of nitrates does not cause an increase in the level of methemoglobin in the blood, while the use of water with a concentration of 50–100 mg/l sharply increases this level. Methemoglobinemia is manifested by cyanosis, an increase in the content of methemoglobin in the blood, and a decrease in blood pressure. These symptoms were registered not only in children, but also in adults. The content of nitrates in drinking water at the level of 10 mg/l is harmless.
Uranium is a radioactive element widely distributed in natural waters.
Especially high concentrations can be found in groundwater. The rationing of uranium is based not on its radioactive properties, but on its toxic effect as a chemical element. The permissible content of uranium in drinking water is 1.7 mg/l.
Cadmium accumulating in the kidneys causes hypertension, weakens the body's immunity, and has a negative effect on the mental abilities of a person, because displaces zinc necessary for normal brain function.
Aluminum, accumulating in the body, can cause senile dementia, increased excitability, cause disturbances in motor reactions in children, anemia, headaches, kidney and liver disease, colitis, and neurological changes associated with Parkinson's disease.
The maximum permissible concentration in water of some additives used to clarify water (for example, polyacrylamide, aluminum sulfate) is also strictly regulated.
There is such an indicator as permanganate oxidizability (the standard is 5 mg O2 / l, not more, this is the total oxygen concentration corresponding to the amount of permanganate ion (MnO4-) consumed during the treatment of a water sample with this oxidizing agent), which characterizes the measure of the presence of organics in water (gasoline, kerosene, phenols, pesticides, herbicides, xylenes, benzene, toluene) and oxidizable inorganic substances (iron salts (2+), nitrites, hydrogen sulfide). Organic substances that cause an increased value of permanganate oxidizability adversely affect the liver, kidneys, reproductive function, as well as the central nervous and immune systems of a person. Water with a permanganate oxidizability higher than 2 mg O2/l is not recommended for drinking.
The toxicity of the above components is not so great as to cause acute poisoning, but with prolonged use of water containing the above substances in concentrations above the norm, chronic intoxication may develop, eventually leading to one or another pathology. It should also be taken into account that the toxic effects of substances can manifest themselves not only when they are taken orally (through the mouth) with water, but also when absorbed through the skin during hygienic (shower, bath) or health-improving (swimming pools) procedures. Thus, in order to answer the question about the suitability of water for drinking, it is necessary to evaluate the sample at least according to the above parameters.
According to sanitary standards, any water that flows from a tap must meet drinking water standards. However, how far these standards are from the quality of hot water. At the time of hot water supply from the station, the temperature is 130 degrees. Naturally, not a single microbe can withstand such heat. However, on its way, along rusty and demolished heating networks, the liquid is not only saturated with living and very harmful microorganisms, but also with chemically hazardous substances. First of all, it is iron, lead, arsenic, chromium, mercury. The main threat, primarily to the health of hair and skin, is active chlorine, which at high temperatures forms an extremely toxic substance in water - dioxin. The microbes and microelements accumulated in hot water are detrimental to damaged areas of the skin and hairline. Skin diseases and hair diseases in many ways become a serious problem due to the ingress of pathogenic substances into the affected areas.
