The main sources of pollution of surface waters are. Surface water pollution

Surface waters are exposed to the strongest anthropogenic impact. Industrial effluents from chemical, oil refineries, metallurgical, tanneries, textile and paper-pulp factories and combines spoil the water especially badly, and

Many environmentally hazardous substances enter water bodies, flowing down during rains and snowmelt from fields, pastures and livestock farms. These may include nitrogen compounds, pesticides, phosphorus, and the like. This type of pollution is especially dangerous because the waters flowing from the fields are not treated at all. The source of pollution causing many problems can be gas-smoke and dust compounds. They can settle on the surface of the water from polluted air.

The increased content of organic matter, as a rule, leads to increased contamination of the water of rivers flowing through densely populated areas.

Groundwater pollution

Pollution of ground and interstratal waters occurs mainly due to the leakage of process and waste waters, as well as in the presence of adjacent filtering earthworks used to collect, store and evaporate liquid production wastes. Depending on the nature of production, heavy metals, aromatic substances, oil products and many others can pass into groundwater along with wastewater. Bacterial pollution, nitrogen compounds, surfactants, which are part of synthetic detergents. With the uncontrolled use of pesticides, mineral fertilizers and pesticides in agriculture, the latter, together with irrigation and atmospheric waters also pollute groundwater. The fight against pollution that got into groundwater is extremely difficult and requires expensive cleaning measures, therefore, thorough preventive measures are the main means of protecting groundwater.

Pollution of the oceans

The ever-increasing pressure on the oceans leads to gradual degradation marine ecosystems. The seas are polluted as a result of direct discharge, the flow of pollution along with the water of rivers flowing into the seas, as a result of accidents sea vessels, due to the direct deposition of various types of pollution from the atmosphere and in other ways. The consequence of such contamination may be their inclusion in the "food chain" through the contamination of marine animals and other products of marine origin. The greatest danger is oil pollution. Oil products do not mix with water, but forming a film on its surface, they prevent air exchange between water and the atmosphere. As a result of depletion of water with oxygen, plankton dies and, as a result, this disrupts the vital activity of other inhabitants of the sea - fish and waterfowl. Ocean waters, like other types of water, are also polluted by other types of industrial substances.

Thermal pollution of water bodies

Upon receipt electrical energy, a large amount of excess heat is produced in industry, cooling is carried out using a large amount of water, which is then discharged into the environment, primarily into water bodies. As a result, the temperature of the water in the reservoirs rises, which has a bad effect on the ecosystems of the reservoirs. Thermal pollution smooths out seasonal temperature fluctuations in water bodies, disrupting life cycle some species of fish and plants.

The concept of rational nutrition. Physiological norms of nutrition.

Rational nutrition is nutrition that ensures the growth, normal development and vital activity of a person, contributing to the improvement of his health and the prevention of diseases. The energy value daily diet should correspond to the energy consumption of the body.

Rational nutrition includes 3 components:

ü Physiological norm;

ü Norms of food consumption;

ü Diet mode.

Physiological norms- these are scientifically based nutritional standards that completely cover the energy expenditure of the body and provide it with all the nutrients in the proper quantities and in the most optimal ratios.

According to the current standards, 5 groups are distinguished among men and 4 groups among women, depending on the intensity of work and daily energy consumption.

Labor Intensity Groups

To the first group are predominantly knowledge workers. The energy expenditure of this group ranges from 2550 to 2800 kcal. This group is divided into three age subgroups. There are groups of 18-29 years old, 30-39 years old and 40-59 years old.

Second group of the population in terms of labor intensity is represented by workers engaged in light physical labor. These are engineering and technical workers, whose work is associated with some physical effort, workers in the radio-electronic, watch industry, communications and telegraph, service industries serving automated processes, agronomists, livestock specialists, nurses and nurses. The energy costs of the second group are 2750-3000 kcal. This group, like the first, is divided into 3 age categories.

Third group of the population in terms of labor intensity is represented by workers engaged in medium-heavy work. These are locksmiths, turners, adjusters, chemists, drivers of vehicles, water workers, textile workers, railway workers, surgeons, printers, foremen of tractor and field teams, grocery store sellers, etc. The energy expenditure of this group is 2950-3200 kcal.

to the fourth group include workers of heavy physical labor - machine operators, agricultural workers, workers in the gas production and oil industry, metallurgists and foundry workers, woodworkers, carpenters and others. For them, energy costs are 3350-3700 kcal.

Fifth group- workers engaged in especially hard physical labor: workers underground mines, chippers, masons, fellers, steelworkers, diggers, loaders, concrete workers whose labor is not mechanized, etc. This group includes only male representatives, since the law prohibits women's work with such labor intensity. This is especially hard physical labor, because the energy costs here are in the range from 3900 to 4300 kcal.

There is a special provision on the rational nutrition of persons engaged in physical education and sports. Nutrition is of particular importance for people with various diseases- Medical nutrition. For persons employed in certain industries, where certain professionally harmful physical and chemical factors are affected, therapeutic and preventive nutrition is used. In general, the issue of nutrition should be addressed individually.

Everyone should receive individual rational nutrition, taking into account the state of health. In the world there is a concept of the nutritional status of a person. This is a state of health based on nutrition.

Nutrition is one of the main determinants of human health. The catering of the collective is associated with the type of institution (kindergarten, school, industrial institution, field camp, medical institutions, army, etc.), the number of people and the duration of their stay in this institution. In most cases, medical workers themselves take part in catering and exercise medical control over it in order to prevent alimentary diseases.

10. Environmental problems human nutrition. The concept of foreign substances and the food chain. Food additives, metals, Carcinogenic substances, nitro compounds, mycotoxins. Pollution migrating from equipment, inventory, containers, etc.

Food (trophic) chain

Nutritional supplements- Substances added for technological purposes to food products during production, packaging, transportation or storage to give them the desired properties, for example, a certain aroma (flavors), color (dyes), shelf life (preservatives), taste, texture, etc. P.

Metals and other trace elements― it is the most often getting into food chemical in-va. They can come not only with food, but also with inhaled air and drinking water, however, the alimentary (food) route is the main one. For the majority of biomicroelements, the optimal physiological need has been determined.

Carcinogenic substances. carcinogen - chemicals, physical radiation or oncogenic viruses, the impact of which on the human or animal body increases the likelihood of malignant neoplasms. Carcinogenic polycyclic hydrocarbons - large group carcinogens formed during the combustion of organic substances; has more than 200 compounds that are common environmental pollutants. For example, in the world annually 7 thousand tons of 3,4-benzpyrene are released into the environment - only one representative of this group of carcinogens. Carcinogens of this group can cause cancer of the lung, gastrointestinal tract, skin and other organs in humans. Carcinogenic polycyclic hydrocarbons get into vegetable, fish and meat products from the environment polluted by industrial emissions, combustion products of fuel from thermal power plants and vehicles. Pollution of air, water and soil leads to the ingress of carcinogenic polycyclic hydrocarbons into plant products. In animals, polycyclic hydrocarbons break down quickly, so their content in meat, dairy and fish products is usually low.

Nitroso compounds- carcinogenic nitroso compounds can enter products from a polluted environment, they are found in small amounts in smoked, dried, canned meat and fish, dark beers, dry and salted fish, pickled and salted vegetables. However, the main food contamination is the precursors of nitroso compounds: nitrates and nitrites. As a result of modern agrochemical measures, the use of mineral fertilizers, vegetables and other plant products contain quite a lot of nitrates. By themselves, nitrates are safe. The danger lies in the fact that about 5% of nitrates are reduced in food or in the body to nitrites, which, in turn, are precursors of carcinogenic nitroso compounds. Other precursors of nitroso compounds - amines and amides - are found in a variety of food products. As a result of nitrosation of amines and amides with nitrites, carcinogenic nitroso compounds (nitrosamines and nitrosamides) appear. The synthesis of carcinogenic nitroso compounds from precursors proceeds spontaneously in products at room temperature. Processing products with smoke, frying, canning and salting sharply accelerate the formation of carcinogenic nitroso compounds in them. In contrast, food storage low temperatures in refrigerators sharply slows down their formation. The synthesis of carcinogenic nitrosamines and nitrosamides from food precursors also occurs in the body itself: the stomach, intestines and bladder. In a study, volunteers were given vegetable juice high in nitrates, after which they found in their urine a large number of nitroso compounds. Carcinogenic nitroso compounds can cause tumors in the stomach, esophagus, liver, nasal cavity, pharynx, kidneys, bladder, brain and other organs in humans.

Pollution migrating from equipment, inventory, containers, etc.- most often occurs through salts heavy metals(copper, zinc, lead, etc.) that get into products from kitchen utensils, equipment, storage containers and packaging materials. In order to prevent the adverse effects on the human body of organic in-in polymer materials migrating into food, it is necessary to comply with the rules for using dishes and products made from them. To avoid dangerous consequences plastic utensils should be used for packaging and storage of only those products for which they are intended.

Ecological problems of human nutrition. The concept of foreign substances and the food chain. Components that get into food from fertilizers, pesticides, livestock and poultry medicines.

Alien chemicals (FCH) include compounds that, by their nature and quantity, are not inherent in a natural product, but can be added in order to improve technology, preserve or improve the quality of the product and its nutritional properties. They can be formed in the product during processing and storage, and also get into it or food due to contamination. 30 to 80% alien in-in enter the body with food.

Food (trophic) chain- a series of relationships between groups of organisms (plants, animals, fungi and microorganisms), in which there is a transfer of matter and energy by eating some individuals by others.

Components that get into food from mineral and other fertilizers. Due to the use of various types of fertilizers in plant and then animal products, nitrates, nitrites, other nitrogen-containing compounds, as well as a number of metals can accumulate. Plants absorb nitrate through the root system in two ways: by reducing nitrate to nitrite and by reducing nitrate to ammonia. Nitrates are found in high concentrations in the roots, stems, petioles and veins of plants. Leaves and roots are richer in nitrates than fruits. Culinary processing of products reduces the concentration of nitrates (cleaning, washing, soaking products reduces it by 15-20%). When cooking vegetables, up to 80% of nitrates are washed into the broth.

Some of the nitrates and nitrites that enter the gastrointestinal tract are metabolized by the microflora of the stomach and intestines, and the rest is absorbed. Nitrites entering the blood interact with hemoglobin, forming nitrosohemoglobin, which is transformed into methemoglobin and partially into sulfohemoglobin. The threshold dose of nitrite ion, causing an increase in the concentration of methemoglobin, is 0.05 mg per 1 kg of body weight. Prevention: reducing the use of nitrate fertilizers, the work of the agrochemical service.

By chemical composition: inorganic and organic;

According to the intended purpose: insecticides (destruction of insects); acaricides (mites); lamacites (clams/slugs); nematicides (worms); fungicides (microscopic fungi—mold); herbicides (weeds); zoocides (small animals); bactericides; defoliants (stimulation of the shedding of leaves by plants), etc. When processing crops and animals, residual amounts of pestiides can be stored in food and enter the human body, causing poisoning.

Pollution processes surface water are due to various factors. The main sources of pollution and clogging of water bodies are insufficiently treated wastewater from industrial and municipal enterprises, large livestock complexes, production waste from the development of ore minerals; water mines, mines, processing and alloying of timber; water and rail transport discharges; flax primary processing waste, pesticides, etc.

The main ones include:

Discharge of untreated wastewater into water bodies;

Washout of pesticides by heavy rainfall;

Gaseous emissions;

Leaks of oil and oil products

Pollutants, getting into natural water bodies, lead to qualitative changes in water, which are mainly manifested in a change in the physical properties of water, in particular, the appearance of unpleasant odors, tastes, etc.); in change chemical composition water, in particular, the appearance of harmful substances in it, the presence of floating substances on the surface of the water and their deposition at the bottom of reservoirs.

The greatest harm to water bodies and streams is caused by the release of untreated wastewater into them. Wastewater is divided into three groups: fan, or fecal; household, including drains from the galley, showers, laundries, etc.; shale, or oil-bearing.

Fan wastewater is characterized by high bacterial pollution, as well as organic pollution (chemical oxygen consumption reaches 1500-2000 mg/l), the volume of these waters is relatively small.

Domestic wastewater is characterized by low organic pollution. This wastewater is usually discharged overboard as it is generated. Dumping them is prohibited only in the zone of sanitary protection.

Shale waters are formed in the engine rooms of ships. They are distinguished by a high content of petroleum products.

Industrial wastewater is polluted mainly by industrial waste and emissions. quantitative and qualitative composition their diversity and depends on the industry, its technological processes; they are divided into two main groups: containing inorganic impurities, incl. both toxic and containing poisons. The first group includes wastewater from soda, sulphate, nitrogen-fertilizer plants, processing plants for lead, zinc, nickel ores, etc., which contain acids, alkalis, heavy metal ions, etc.

The wastewater of this group mainly changes physical properties water. Wastewater of the second group is discharged by oil refineries, petrochemical plants, enterprises organic synthesis, coke, etc. Effluent contains various oil products, ammonia, aldehydes, resins, phenols and other harmful substances. The harmful effect of wastewater of this group lies mainly in oxidative processes, as a result of which the oxygen content in water decreases, the biochemical demand for it increases, and the organoleptic indicators of water deteriorate. The life of the population of reservoirs is adversely affected by wastewater from the pulp and paper industry. Oxidation of wood pulp is accompanied by the absorption of a significant amount of oxygen, which leads to the death of eggs, fry and adult fish. Fibers and others insoluble substances clog water and worsen its physical and chemical properties. Mole alloys adversely affect fish and their food - invertebrates. From rotting wood and bark, various tannins are released into the water. Resin and other extractive products decompose and absorb a lot of oxygen, causing the death of fish, especially juveniles and eggs. In addition, mole alloys heavily clog rivers, and driftwood often completely clogs their bottom, depriving fish of spawning grounds and food places. Huge amounts of hazardous pollutants such as pesticides, ammonium and nitrate nitrogen, phosphorus, potassium, etc. are washed away from agricultural areas, including areas occupied by livestock complexes. For the most part, they enter water bodies and watercourses without any treatment, and therefore have a high concentration of organic matter, nutrients and other pollutants.

A significant danger is posed by gas-smoke compounds (aerosols, dust, etc.) settling from the atmosphere onto the surface of watersheds and directly onto water surfaces. The density of deposition, for example, of ammonium nitrogen in the European territory of Russia is estimated at an average of 0.3 t/km2, and sulfur from 0.25 to 2.0 t/km2.

Oil and oil products at the present stage are the main pollutants of inland waters, waters and seas, the World Ocean. Once in the water bodies, they create different forms pollution: oil film floating on water, oil products dissolved or emulsified in water, heavy fractions settled to the bottom, etc. This hinders the processes of photosynthesis in water due to the cessation of access sun rays and also causes death of plants and animals. At the same time, the smell, taste, color, surface tension, viscosity of water change, the amount of oxygen decreases, harmful organic substances appear, water acquires toxic properties and poses a threat not only to humans. 12 g of oil makes a ton of water unfit for consumption. Each ton of oil creates an oil film on an area of up to 12 square meters. km. Restoration of affected ecosystems takes 10-15 years.

In addition to surface water, groundwater is also constantly polluted, primarily in the areas of large industrial centers. Sources of groundwater pollution are very diverse.

Pollutants can reach groundwater different ways: when industrial and household wastewater seeps from storage facilities, storage ponds, settling tanks, etc., through the annulus of faulty wells, through absorbing wells, sinkholes, etc.

It is important to emphasize that groundwater pollution is not limited to the area of industrial enterprises, waste storage facilities, etc., but spreads downstream to distances of up to 20–30 km or more from the pollution source. It creates real threat for drinking water supply in these areas.

It should also be borne in mind that groundwater pollution has a negative impact on the ecological state of surface water, atmosphere, soil, and other components. natural environment. For example, contaminants found in groundwater can be carried by seepage flow to surface water bodies and pollute them. As many scientists emphasize, the circulation of pollutants in the system of surface and ground waters predetermines the unity of environmental and water protection measures and they cannot be broken. Otherwise, measures to protect groundwater without regard to measures to protect other components of the natural environment will be ineffective.

Natural sources of pollution include highly mineralized (salty and brine) groundwater or sea waters, which can be introduced into fresh unpolluted waters during the operation of water intake facilities and pumping water from wells.

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1. Introduction
2. Types of pollution
conclusions
Bibliography
Applications

1. Introduction

Throughout their history, people have used surface waters (rivers, lakes) for their economic needs. This did not bring significant harm, since nature itself provided self-purification of reservoirs. In the XX century. the situation has changed dramatically. Urbanization, industrial growth and development Agriculture caused pollution of rivers and lakes all over the world.

Water pollution is an artificial change in the chemical and physical state, as well as the biological characteristics of water, as a result of which its further use is limited. Water pollution - in the legislation Russian Federation is regarded as an environmental crime, the objective basis of which is pollution, clogging, depletion of surface water, groundwater, sources of drinking water supply, as well as other changes in their properties, during which significant harm was caused to the animal or plant world, fish stocks, forestry or agriculture . Depending on the severity of the consequences, water pollution can be considered an administrative or criminal offense.

Most water quality water bodies does not answer regulatory requirements. Long-term observations of the dynamics of surface water quality reveal a trend towards an increase in the number of sites with a high level of pollution (more than 10 MPC) and the number of cases of extremely high content (over 100 MPC) of pollutants in water bodies. The state of water sources and centralized water supply systems cannot guarantee the required quality of drinking water. This condition has reached dangerous levels for human health. Sanitary and epidemiological surveillance services constantly note high pollution of surface waters.

2. Types of pollution

About 1/3 of the total mass of pollutants is introduced into water sources with surface and storm runoff from the territories of sanitary unimproved places, agricultural facilities and lands, which affects the seasonal, during the spring flood, deterioration in the quality of drinking water, annually noted in major cities. The main pollutants of surface waters:

oil and oil products;

· wastewater;

ions of heavy metals;

· acid rain;

· radioactive contamination;

thermal pollution;

· mechanical pollution;

bacterial and biological contamination.

The main sources of adverse effects on surface water bodies and their pollution are sewage - liquid waste from human household and industrial activities. Waste water is called water, which was formed after the use of drinking water by a person to meet certain needs in everyday life or at work. At the same time, additional impurities (pollution) got into the water, which changed and worsened its composition. Depending on the origin, wastewater is divided into:

1) household, or household and fecal, formed as a result of household activities of people mainly in residential and public buildings;

2) industrial, formed on industrial enterprises, as a result of technological production processes);

pollution surface water source

3) storm (atmospheric), formed as a result of the formation of surface runoff from asphalt and other coatings and soil during precipitation and snow melting. They flow into water bodies from the territories of populated areas, industrial sites and agricultural fields;

4) urban, which means a mixture of domestic and industrial wastewater generated in a settlement as a result of the discharge of untreated or pretreated industrial wastewater into the city sewer;

5) drainage water from irrigated lands;

6) waste water from livestock complexes;

7) wastewater from storage ponds that are discharged into water bodies during the spring flood. There are cases of forced discharge of sewage from reservoirs, with insufficient flow of the river, into regulated reservoirs, during floods, etc.;

8) sewage (fan) of passenger ships of the sea and river (including small size) fleet, cargo and oil terminals and courts.

In addition, water bodies are polluted when sand is taken and other works are carried out in their channel. Soaking fibrous plants in them, such as flax or hemp, leads to pollution of water bodies. Pollutes water bodies and timber rafting. Surface water bodies can be polluted through atmospheric air. Water bodies can also become polluted due to mass die-off in them. aquatic organisms, animals and plants, especially in autumn, resuspension of bottom sediments.

When entering water bodies, untreated or insufficiently treated wastewater pollutes them with suspended particles, organic substances, pathogenic and opportunistic bacteria, viruses, protozoan cysts, and helminth eggs. With industrial wastewater, a significant amount of toxic chemicals enters water bodies.

Polluted water bodies lose their importance as a positive factor in maintaining the health of the population. The use of polluted water bodies can lead to water epidemics, mass poisoning of the population with toxic, carcinogenic, radioactive, allergenic, mutagenic substances. Reservoirs cause great harm to fish and fur farming, lose their health-improving value.

Oil and oil products at the present stage are the main pollutants of inland waters, waters and seas, the World Ocean. Getting into water bodies, they create different forms of pollution: oil film floating on water, dissolved or emulsified in water. Oil products, heavy fractions settled to the bottom, etc. At the same time, the smell, taste, color, surface tension, viscosity of water change, the amount of oxygen decreases, harmful organic substances appear, water acquires toxic properties and poses a threat not only to humans. 12 g of oil makes a ton of water unfit for consumption. Nuclear power plants radioactive waste pollute rivers. radioactive substances are concentrated by the smallest planktonic microorganisms and fish, then transmitted along the food chain to other animals. It has been established that the radioactivity of planktonic inhabitants is thousands of times higher than the water in which they live. The main source of radioactive pollution of the sea is low-level waste removed from nuclear power plants. One of the most important problems arising from this contamination is that marine organisms such as algae accumulate, or concentrate, radioactive isotopes. Thermal water pollution is caused by thermal or nuclear power plants. Thermal pollution is introduced into the surrounding water bodies by waste cooling water. As a result, an increase in water temperature in these reservoirs leads to an acceleration of some biochemical processes, as well as to a decrease in the content of oxygen dissolved in water. This causes rapid and often very significant changes in the biological environment near power plants. There is a violation of the finely balanced cycles of reproduction of various organisms. In conditions of thermal pollution, as a rule, there is a strong growth of algae, but the extinction of other organisms living in the water.

3. Wastewater treatment methods

In rivers and other bodies of water natural process water self-purification. However, it runs slowly. While industrial and household discharges were small, the rivers themselves coped with them. In our industrial age, due to a sharp increase in waste, water bodies can no longer cope with such significant pollution. There was a need to neutralize, purify wastewater and dispose of them.

cleaning sewage waters- treatment of wastewater to destroy or remove harmful substances from them. The release of wastewater from pollution is a complex production. It, like in any other production, has raw materials (waste water) and finished products (purified water)

Wastewater treatment methods can be divided into:

mechanical,

chemical,

physicochemical and

biological,

when they are used together, the method of purification and disposal of wastewater is called combined. The use of a particular method in each specific case is determined by the nature of the pollution and the degree of harmfulness of impurities.

The essence of the mechanical method is that mechanical impurities are removed from wastewater by settling and filtration. mechanical cleaning allows you to isolate up to 60-75% of insoluble impurities from domestic wastewater, and up to 95% from industrial wastewater, many of which are used in production as valuable impurities. The chemical method consists in the fact that various chemical reagents are added to the wastewater, which react with pollutants and precipitate them in the form of insoluble precipitates. Chemical cleaning achieves a reduction of insoluble impurities up to 95% and soluble impurities up to 25%.

With the physico-chemical method of treatment, finely dispersed and dissolved inorganic impurities are removed from wastewater and organic and poorly oxidized substances are destroyed. Electrolysis is also widely used. It consists in the destruction of organic substances in wastewater and the extraction of metals, acids and other inorganic substances. Electrolytic purification is carried out in special facilities - electrolyzers. Wastewater treatment using electrolysis is effective in lead and copper plants, paint and varnish and some other industries.

Contaminated wastewater is also cleaned using ultrasound, ozone, ion exchange resins and high pressure, cleaning by chlorination has proven itself well. Among the wastewater treatment methods, a biological method based on the use of the laws of biochemical and physiological self-purification of rivers and other water bodies should play an important role. There are several types of biological wastewater treatment devices: biofilters, biological ponds and aeration tanks. In biological ponds, all organisms inhabiting the reservoir take part in wastewater treatment.

Aerotanks are huge reinforced concrete tanks. Here, the purifying principle is activated sludge from bacteria and microscopic animals. All these living creatures are rapidly developing in aerotanks, which is facilitated by the organic matter of sewage and the excess of oxygen entering the structure by the flow of supplied air. Bacteria stick together into flakes and secrete enzymes that mineralize organic pollution. Silt with flakes quickly settles, separating from the purified water. Infusoria, flagellates, amoebae, rotifers and other smallest animals, devouring bacteria that do not coalesce into flakes, rejuvenate the bacterial mass of sludge.

Wastewater is subjected to mechanical treatment before biological treatment, and after it for removal pathogenic bacteria and chemical cleaning, chlorination with liquid chlorine or bleach. For disinfection, other physical and chemical methods are also used (ultrasound, electrolysis, ozonation, etc.)

The biological method gives great results in the treatment of municipal wastewater. It is also used in the treatment of waste from oil refineries, the pulp and paper industry, and the production of artificial fibers.

4. History of surface water pollution in Russia

Pollution of surface waters began in central Russia as early as the 16th century, when fields were fertilized with manure. Since then in central regions The country's main water pollutant was agriculture. In the more northern regions, timber rafting, especially mole rafting, played a large role in pollution, in which the logs sank and rotted in the water. With the development of industry and the growth of cities, the role of communal and industrial pollution. A sharp increase in pollution occurred in the twentieth century. A particular danger is associated with the coincidence of the period of growth in discharges of polluted wastewater and the centuries-old trend of increasing dryness of the climate, and a decrease in the water content of water bodies. Under these conditions, the concentrations of pollutants in solutions increase and, consequently, the degree of their harmful effect on natural systems and human health. By the beginning of the 1990s, the main pollutants of surface waters were oil products, phenols, easily oxidized organic substances, copper and zinc compounds, ammonium and nitrate nitrogen. (Attachment 1)

In most industrialized regions of the country, wastewater discharges amounted to more than 100 cubic meters. m per capita. in the Irkutsk region and Krasnodar Territory it exceeded 500 cu. m per person. In the main industrial centers - Moscow, Nizhny Novgorod region etc. - more than 200, in St. Petersburg - more than 300. But for several decades, as a result of industrial and municipal discharges of polluted water, it is impossible to drink water from the Middle and Lower Volga. Despite the relatively high degree of provision of the basin with industrial and municipal treatment facilities for Russia, they do not work efficiently. Thus, the following was discharged into the reservoirs of the basin: oil products - 6.8 thousand tons, suspended solids - 257 thousand tons, sulfates - 1344 thousand tons, organic pollutants 176 thousand tons, total nitrogen- 12 thousand tons, nitrates - 69.7 thousand tons, iron - 35 thousand tons, zinc - 0.6 thousand tons, aluminum - 5.5 thousand tons, magnesium - 10.7 thousand tons, and mercury - 61 kg. . It is with this water that gardens and melons are watered in the Volga-Akhtuba floodplain, with products from which a significant part of the population of Russia is supplied. Fish from the Volga and Caspian deltas also live in this polluted water. The abundance of pathologies caused by water pollution in Caspian sturgeons is widely known. The bottoms of the Volga reservoirs are covered with silts containing, for example, huge concentrations of heavy metals, which, if they are washed out (for example, at especially low water levels or serious accidents of hydroelectric dams), can drastically worsen the ecological state of the entire basin. In general, the Volga-Caspian basin, in which 80 million people live, is perhaps the most dangerous in Russia in terms of the state of the water. The huge basin of the Ob River is extremely polluted by oil production. Salekhard, standing at the confluence of the huge Ob with its large tributary Poluy, is experiencing great difficulties with clean drinking water, it is transported around the city in cisterns. There are much more exotic species pollution. In almost all gold-mining provinces, the waters are heavily polluted with mercury, which is used for amalgamation in the gold-mining industry. But in some places they went further - for example, in the Aldan region, cyanides were used for this purpose. Banners were placed along the rivers forbidding drinking water, but cows and elks and, much worse, children cannot read. Although Russia owns the world's largest, completely unique reservoir of the purest fresh water- oz. Baikal, the situation on it inspires concern, especially in connection with the activities of the Baikal Pulp and Paper Mill and the Selenginsky CCC, with wastewater from which up to 60% of hardly decomposable organic substances enter Baikal.

5. Impact of polluted surface water bodies on human health

Pollution of surface water bodies has a direct and indirect effect on human health. A direct harmful effect can manifest itself both when water enters the human body orally (a person deliberately drinks water from a polluted reservoir or accidentally swallowed it while swimming), and when it comes into contact with the skin and mucous membranes while swimming, bathing, etc. But more often In total, the harmful effect is carried out according to the scheme: polluted water of a surface reservoir - drinking water - a person. This is explained by the fact that technologies for the preparation of drinking water from surface water sources make it possible to improve only some of its properties. In particular, to reduce turbidity and color due to clarification and discoloration, to get rid of the epidemic danger by disinfection, to improve some indicators of the mineral composition by special methods of water treatment (desalination, softening, fluorination, defluorination, etc.). These technologies are sometimes not designed to remove certain harmful chemicals from the water. If their concentration in the reservoir at the water intake points significantly exceeds the MPC, they can pass water treatment facilities practically in transit, get into drinking water, and with drinking water - into the human body. Consequently, on the one hand, the consumption or use by the population of water from reservoirs contaminated with enteropathogenic bacteria and viruses, protozoa, helminths, can lead to mass infectious diseases and invasions, and on the other hand, the use by humans of polluted water, which contains harmful chemicals in concentrations exceeding the MPC, can cause acute or chronic poisoning with possible long-term consequences (allergenic, teratogenic, mutagenic, carcinogenic).

Indirect, or indirect, harmful effect of water bodies on human health occurs according to the scheme: polluted water - contaminated food ("seafood") - a person; polluted water body - irrigation of agricultural land - food plant origin- human; polluted reservoir - cattle watering place - milk - human, etc. That is, the indirect harmful effect of polluted reservoirs on human health can occur when eating fish, other food products made from raw materials obtained from polluted reservoirs; when using water contaminated with enteropathogenic bacteria and viruses or toxic chemicals, for washing vegetables, fruits, berries, while relaxing on the shore of a reservoir, sports events, etc.

The consequences of the impact of polluted water in reservoirs on human health can be summarized as follows:

drinking quality tap water largely depends on the quality of water in a surface water body, which is a real or can be a potential source of centralized water supply;

pollution of water bodies leads to a reduction in food resources due to the inability to consume fish, fish products, other "seafood", which can be contaminated with various toxic chemicals: heavy metals, organochlorine pesticides, polychlorinated biphenyls, etc.;

polluted waters of reservoirs cannot be used for irrigation of agricultural land, as this hinders the development of agriculture. Such waters cannot also be used in animal husbandry and poultry farming;

loss of water due to pollution raw material for National economy. Thus, cases of mass diseases and death of sheep on pastures located on islands near Great Britain are known. Animals have died from eating seaweed high in mercury and arsenic.

conclusions

The main sources of surface water pollution today are:

industrial enterprises;

· livestock complexes, farms and poultry farms;

thermal and nuclear power plants;

public utility companies;

storm drains from urban areas;

· Agriculture;

· water transport;

· precipitation;

· hydraulic structures, regulation of river flow and creation of reservoirs.

In a number of areas, water bodies are also polluted during the extraction of minerals and peat extraction. Per recent decades Recreation has become a significant source of pollution of rivers and reservoirs, especially such types of it as mass bathing and small fleets.

The current level of wastewater treatment is such that even in waters that have undergone biological treatment, the content of nitrates and phosphates is sufficient for irreversible environmental changes in water bodies.

Of course, all of the above negatively affects human health and well-being and indicates that the problem of sanitary protection of water bodies is of both medical (hygienic) and national economic importance.

Bibliography

1. Martynov et al. Analysis of socio-economic factors affecting the state biodiversity. Preparatory phase of the GEF project “Conservation of the biological diversity of Russia” (Appendix 1) - M., PAIMS, 1995-288 p., ill.

2. Journal "Ecological Norms. Rules. Information" No. 1, 2007

3. Badtiev Yu.S., Barkov V.A., Usov G.P. Bioindication of surface water bodies. // Ecology and industry of Russia. - 2003 - July. - S.24-26.

4. http://www.uzenbash.ru/okruzhajuscheaja-sreda/prirodnaja-sreda/14/

5. http://www.monolith. info/poleznaya-informatsiya/zagryaznenie-poverhnostnyih-vod.html

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The main pollutants of surface waters. How do pollutants get into surface water?

The water quality of most water bodies does not meet regulatory requirements. Long-term observations of the dynamics of surface water quality reveal a trend towards an increase in the number of sites with a high level of pollution (more than 10 MPC) and the number of cases of extremely high content (over 100 MPC) of pollutants in water bodies.

The state of water sources and centralized water supply systems cannot guarantee the required quality of drinking water, and in a number of regions ( Southern Urals, Kuzbass, some territories of the North) this state has reached a dangerous level for human health. Sanitary and epidemiological surveillance services constantly note high pollution of surface waters.

About 1/3 of the total mass of pollutants is introduced into water sources with surface and storm runoff from the territories of sanitary unimproved places, agricultural facilities and lands, which affects the seasonal, during the spring flood, deterioration in the quality of drinking water, annually noted in large cities, including including in Moscow. In this regard, water is hyperchlorinated, which, however, is unsafe for public health due to the formation of organochlorine compounds.

One of the main pollutants of surface waters is oil and oil products. Oil can get into the water as a result of its natural outflows in the areas of occurrence. But the main sources of pollution are associated with human activities: oil production, transportation, processing and use of oil as fuel and industrial raw materials.

Among industrial products, toxic synthetic substances occupy a special place in terms of their negative impact on the aquatic environment and living organisms. They find more and more wide application in industry, transport, public utilities. The concentration of these compounds in wastewater, as a rule, is 5-15 mg/l at MPC - 0.1 mg/l. These substances can form a layer of foam in reservoirs, which is especially noticeable on rapids, rifts, locks. The ability to foam in these substances appears already at a concentration of 1-2 mg / l.

The most common pollutants in surface waters are phenols, easily oxidized organic substances, compounds of copper, zinc, and in some regions of the country - ammonium and nitrite nitrogen, lignin, xanthates, aniline, methyl mercaptan, formaldehyde, etc. A huge amount of pollutants is introduced into surface water with wastewater from ferrous and non-ferrous metallurgy enterprises, chemical, petrochemical, oil, gas, coal, timber, pulp and paper industries, agricultural and municipal enterprises, surface runoff from adjacent territories.

little danger to aquatic environment of metals are mercury, lead and their compounds. Expanded production (without treatment facilities) and the use of pesticides in the fields lead to severe pollution of water bodies with harmful compounds. Pollution of the aquatic environment occurs as a result of the direct introduction of pesticides during the treatment of water bodies for pest control, the ingress of water flowing down from the surface of cultivated agricultural land into water bodies, when waste from manufacturing enterprises is discharged into water bodies, as well as as a result of losses during transportation, storage and partially with atmospheric precipitation.

Along with pesticides, agricultural effluents contain a significant amount of fertilizer residues (nitrogen, phosphorus, potassium) applied to the fields. Besides, large quantities organic compounds of nitrogen and phosphorus come with runoff from livestock farms, as well as with sewage. An increase in the concentration of nutrients in the soil leads to a violation of the biological balance in the reservoir.

Initially, in such a reservoir, the number of microscopic algae sharply increases. With an increase in the food supply, the number of crustaceans, fish and other aquatic organisms increases. Then there is a death huge amount organisms. It leads to the consumption of all the reserves of oxygen contained in the water, and the accumulation of hydrogen sulfide. The situation in the reservoir changes so much that it becomes unsuitable for the existence of any forms of organisms. The reservoir gradually "dies".

The current level of wastewater treatment is such that even in waters that have undergone biological treatment, the content of nitrates and phosphates is sufficient for intensive eutrophication of water bodies.

In many water bodies, the concentrations of pollutants exceed the MPCs established by sanitary and fish protection regulations.

A source that introduces water pollutants, microorganisms or heat into surface or ground water is called a pollution source. A substance that causes a violation of water quality standards (set values of water quality indicators by type of water use) is called a pollutant. Microbial pollution of water occurs as a result of the entry of pathogenic microorganisms into water bodies. Allocate also thermal pollution water as a result of heat input.

The main cause of pollution of water basins is the discharge of untreated or insufficiently treated wastewater into water bodies by industrial enterprises, utilities and agriculture. It has been calculated, for example, that if a city consumes 600,000 m3 of water a day, it produces about 500,000 m3 of sewage. Residues of fertilizers and pesticides washed out of the soil end up in water bodies. and pollute them.

Wastewater - these are waters discharged after use in household and industrial activities of a person.

At present, 150 km 3 of water per year is spent on industrial household needs all over the globe. Compared to the planet's sustainable river flow, this is quite a bit - less than 0.5%. The President of the International Commission on Surface Waters, Professor M. I. Lvovich, calculated the danger this “drop” poses to the sea of freshwater resources. To have 150 km 3 of water at your disposal, you need about to take four times more water from sources - such is the immutable law of water consumption. Consequently, the actual water intake already reaches 600 km 3 per year. The difference of 450 km 3 is return water, again directed to rivers and reservoirs. For neutralization, even after thorough biological treatment, these waters must be diluted with clean water. Dilution rates are sometimes very high. So, for effluents from the production of synthetic fibers, the dilution ratio is 1: 185, for polyethylene or polystyrene - 1: 29.

Worldwide, 5,500 km 3 is spent annually on wastewater treatment pure water- three times more than for all other needs of mankind. This value is already 30% of the stable flow of all rivers the globe. Consequently, the main threat of water shortages is generated not by irretrievable industrial consumption, but by the pollution of natural waters by industrial effluents and the need to dilute them.

Pollution entering wastewater can be conditionally divided into several groups. Yes, by physical condition emit insoluble, colloidal and dissolved impurities. In addition, pollution is divided into mineral, organic, bacterial and biological.

Mineral pollution is usually represented by sand, clay particles, particles of ore, slag, mineral salts, solutions of acids, alkalis and other substances.

Organic pollutants are subdivided according to their origin into plant and animal. Vegetable organic pollution are the remains of plants, fruits, vegetables and cereals, vegetable oil, etc. Animal pollution is the physiological secretions of people and animals, animal tissue residues, adhesives, etc.

Bacterial and biological contamination is characteristic mainly of domestic wastewater and the effluents of some industrial enterprises. Among the latter are slaughterhouses, tanneries, primary wool processing factories, fur production, biofactories, microbiological enterprises, etc.

Domestic wastewater includes water from kitchens, toilets, showers, baths, laundries, canteens, hospitals, household water that is generated during washing of premises, etc. They come from residential and public buildings, from domestic premises of industrial enterprises, etc. In domestic wastewater, organic matter in pollution is 58%, mineral substances - 42% (Table 9).

In industrial production, water is used as a coolant, absorber, solvent, as a means of transportation. Perhaps also the use of water for different purposes at the same time.

Many enterprises of mechanical engineering, metalworking, coke chemistry, oil shale processing, thermal power plants use water for cooling. Water consumption at these enterprises for cooling reaches 80% of the total amount of water used in production.

Water- coolant in technological process mainly heats up, not dirty. However, the water used to cool raw materials, products or equipment is also contaminated by various harmful substances.

At the enterprises of the petrochemical and chemical industries, water is used as a solvent and is part of the product. In this case, as a rule, specific wastewater is formed. In some cases, water plays the role of an absorbent medium and means of transportation (enrichment, washing, cleaning of raw materials and products, etc.). At the same time, it is contaminated with mechanical impurities and soluble chemicals. In chemical, pulp and paper and hydrolysis plants, as well as in enterprises of light and Food Industry water is used as the working medium.

The production and widespread use of synthetic surfactants (surfactants "), especially as part of detergents, led to their entry with wastewater into many water bodies, including sources of domestic and drinking water supply. Currently, these substances are one of the most common chemical pollution of water bodies The inefficiency of water treatment from surfactants in modern water treatment facilities is the cause of their appearance in the drinking water of water pipes. Surfactants can have bad influence on the quality of water, the self-cleaning ability of water bodies, the human body, as well as to increase the adverse effect of other substances on these indicators, therefore, it is necessary to limit their content in water.

All synthetic surfactants are divided into four classes: anionic, nonionic, cationic and ampholytic.

Anionic substances, the most common of the surfactants, are the main integral part synthetic detergents. These include mainly alkyl sulfates, sulfonols, alkyl sulfonates, disodium salt of monoalkyl sulfonic acid (DNS).

Nonionic substances in terms of production, they account for approximately 10% of all other surfactants. To a lesser extent than anionic surfactants, are used in detergents, more - for industrial purposes. These include OP-7, OP-10, sintanols, synthamide, proxanols, proxamines, etc.

Cationic substances constitute an insignificant part of all produced surfactants (fractions of a percent). In detergents, they are used as disinfecting agents.

Surfactants can enter water sources with domestic wastewater as a result of their use in the composition of synthetic detergents (CMC) in everyday life, in laundries; with industrial wastewater during production and as a result of the use of surfactants and CMC in industry; with surface runoff from agricultural fields as a result of the use of surfactants to emulsify pesticides, as well as from areas adjacent to enterprises producing CMC.

Surfactants can get into groundwater as a result of the use of soil methods for treating wastewater containing surfactants, when replenishing groundwater with water from surface water sources and in other soil contamination with these substances.

The average consumption of surfactants per inhabitant is 2.5 g per day. With water disposal rates in the range of 125-350 liters per person per day, the average calculated concentration of surfactants in domestic wastewater will be 7.1-20 mg / l.

Due to the significant content of industrial wastewater in urban effluents, the actual content of surfactants in the mixed effluent is currently most often on average about 5 mg/l. In connection with the development of surfactant production in the future, their content in wastewater will increase significantly.

Of the anionic surfactants, alkylarylsulfonates (sulfonols) and alkyl sulfates predominate in wastewater; DNS (disodium salt of monoalkylsulfosuccinic acid) may also be present, from non-ionic substances - sintanol DS-10 and other substances.

In domestic wastewater, along with surfactants, other CMC ingredients are present, including sodium tripolyphosphate, soda ash, sodium silicate, carboxymethyl cellhalose, optical brighteners, perfumes, alkylolamides, perborates, sodium sulfate and other substances. The constant presence of anionic substances in domestic wastewater, as well as high sensitivity methods of analysis of these substances make them an integral indicator of pollution of water bodies by sewage. From industrial wastewater highest value in pollution of water bodies, surfactants and CMC have effluents from enterprises light industry- textile, fur, leather, where they are used for degreasing raw leather during tanning, for washing cotton yarn, wool, for bleaching, dyeing and printing fabrics, etc.

Surfactants can be found in wastewater from many other industries. This is due to the use of these substances in such processes as the flotation concentration of ores, the separation of chemical technology products, and the production of polymers. In the oil industry, pollution of water sources can be associated with the use of surfactants to improve the conditions for drilling oil and gas wells, flood oil reservoirs, control paraffin deposits, and equipment corrosion. In industrial wastewater, the content of ionic and nonionic substances varies widely. So, in the effluents of primary wool processing enterprises, it exceeds 200 mg/l, in the effluents of some textile and fur factories, it is in the range of 5-50 mg/l.

One of the significant sources of pollution of water bodies are large mechanized laundries, in the effluents of which the content of surfactants is 100-200 mg/l and higher.

Along with surfactants, pesticides are widespread chemical pollutants of water bodies, which enter water bodies with rain and melt water (surface runoff), washing them off from plants and soil; during air and ground processing of agricultural land and forests; at direct processing of reservoirs by pesticides; with drainage-collector waters formed in agricultural production when growing cotton and rice; with wastewater generated in agriculture as a result of the use of pesticides, and effluents from enterprises producing them.

The degree of risk of drifting pesticides during the processing of agricultural land depends on the method of application and the form of the drug. With ground processing, the risk of pollution of water bodies is less. During aerial treatment, the drug can be carried by air currents for hundreds of meters and deposited on an untreated area and on the surface of water bodies.

The decisions of the XXV Congress of the CPSU and the special resolution of the Central Committee of the CPSU "On the further development of specialization and concentration of agricultural production on the basis of inter-farm cooperation and agro-industrial integration" (1976) provide for the further development of one of the most important branches of agriculture - animal husbandry on the basis of specialization, concentration and comprehensive mechanization production. At present, the construction of large livestock farms and complexes for growing and fattening cattle for 3, 6, 10 and 15 thousand, pigs - for 5, 12, 16, 24, 56, 108 thousand and poultry - per 100-150 thousand laying hens per year. The concentration of animals in large farms is the reason for the formation of a significant amount of liquid manure (dares, liquid and solid excrement). By the end of the tenth five-year plan, the annual accumulation of this substrate will amount to 500 million tons. In this regard, it is necessary to take measures to prevent the entry of untreated liquid manure into external environment(soil, water bodies, etc.), as this poses a danger in sanitary and epidemiological terms.

The source of pollution of water bodies with harmful substances is also wastewater from ships, which are divided into three groups: fan, or fecal; household, including drains from the galley, showers, laundries, etc.; subsoil, or oil-containing. Fan wastewater is characterized by high bacterial (if the index reaches 10 10 -10 12), as well as organic pollution (chemical oxygen consumption reaches 1500-2000 mg/l). The volume of these waters is relatively small - the daily amount on all ships of the Volga basin does not exceed 5-6 thousand m 3.

Household wastewater is characterized by low organic pollution, but bacterial pollution is pronounced: the coli index reaches 10 s -10 e. This wastewater is usually discharged overboard as it forms. Their discharge is prohibited in the zone of sanitary protection of water pipes.

Podslanye waters are formed in the engine rooms of ships. They are distinguished by a high content of petroleum products.

In recent years, reservoirs have received many, many thousands of units of the so-called small size fleet (boats, various boats with outboard motors). The small fleet has become a serious pollutant of water bodies.

Surface runoff is also a source of water pollution. The total amount of pollution that enters water bodies and watercourses with surface runoff urbanized territories, is approximately 8-15% of the indicators of pollution of domestic wastewater.

The groundwater.

Allocate microbial and chemical pollution of groundwater. Sources of groundwater pollution can be industrial enterprises and municipal facilities. With microbial contamination of groundwater, some pathogenic bacteria and viruses retain their vital activity for quite a long time (100 or more days).

Groundwater is more often exposed to microbial contamination. The centers of pollution are formed in the presence of sewage and filtration fields, cattle yards, cesspools through which polluted waters are directly filtered. And if soils in the aeration zone lose their cleansing properties, groundwater pollution begins. Particularly dangerous are the sources of pollution in places of well-permeable fractured or coarse-grained rocks. In such cases, pollution with atmospheric precipitation can penetrate into groundwater. Groundwater pollution can also occur when wastewater is discharged into absorbing wells, pits, and wells.

Pollution of artesian waters can occur when wastewater is discharged into absorption wells, as well as when contaminated groundwater flows through corroded pipes and the annulus of abandoned wells with defects. Pollution of groundwater with chemicals can go through polluted surface water, which is used to feed groundwater.

At industrial enterprises, settling ponds, sludge ponds, storage ponds, evaporation ponds, tailings, ash dumps, etc. are used for wastewater treatment. In some cases, they can also be a source of groundwater pollution. When using agricultural irrigation fields and filtration fields for wastewater treatment, pollution of groundwater with harmful chemicals is also not excluded.

Surface-active substances (surfactants) can also enter groundwater. Pollution of surfactants is observed when using soil methods for treating wastewater containing surfactants, when replenishing groundwater from surface water sources containing surfactants.

The source of groundwater pollution can be atmospheric precipitation, polluted in areas occupied by industrial waste, salt dumps, storage areas for oil products, raw materials and finished products enterprises of the chemical industry, warehouses of pesticides and fertilizers.

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