Carbon monoxide (carbon monoxide).

Carbon monoxide- a colorless, odorless gas, slightly lighter than air, poorly soluble in water, has a boiling point: - 191.5°C. In air it ignites at a temperature of 700°C and burns with a blue flame to CO 2 .

Sources of entry into the environment.

Carbon monoxide is part of the atmosphere (10%). Carbon monoxide enters the atmosphere as part of volcanic and swamp gases, as a result of forest and steppe fires, and emission by microorganisms, plants, animals and humans. From the surface layers of the oceans, 220 x 10 6 tons of carbon monoxide are released per year as a result of photodecomposition of red, blue-green and other algae, waste products of plankton. The natural level of carbon monoxide in atmospheric air is 0.01-0.9 mg/m3.

Carbon monoxide enters the atmosphere from industrial enterprises, primarily metallurgy. In metallurgical processes, when smelting 1 million tons of steel, 320-400 tons of carbon monoxide are formed. A large amount of CO is formed in the oil industry and chemical plants (oil cracking, production of formaldehyde, hydrocarbons, ammonia, etc.). Another important source of carbon monoxide is tobacco smoke. The concentration of carbon monoxide is high in coal mines and on coal supply routes. Carbon monoxide is formed during incomplete combustion of fuel in stoves and internal combustion engines. An important source of carbon monoxide is road transport.

As a result of human activity, 350-600x10 6 tons of carbon monoxide enter the atmosphere annually. About 56-62% of this amount comes from motor vehicles (the content of carbon monoxide in exhaust gases can reach 12%).

Behavior in the environment.

Under normal conditions, carbon monoxide is inert. It does not chemically interact with water. The solubility of CO in water is about 1:40 by volume. In solution it is capable of reducing gold and platinum salts to free metals already at normal temperature. CO also does not react with alkalis and acids. Interacts with caustic alkalis only at elevated temperatures and high pressures.

The loss of carbon monoxide in the environment occurs due to its decomposition by soil fungi. In addition, when there is an excess of oxygen in soils of heavy mechanical composition, rich in organic matter, the transition of CO to CO 2 occurs.

Impact on the human body.

Carbon monoxide is extremely poisonous. The permissible CO content in industrial premises is 20 mg/m 3 during the working day, 50 mg/m 3 for 1 hour, 100 mg/m 3 for 30 minutes, in the atmospheric air of the city the maximum one-time (in 20 minutes) is 5 mg/m 3 , average daily MPC - 3 mg/m 3 . The natural level of carbon monoxide in atmospheric air is 0.01-0.9 mg/m3.

CO is inhaled along with air and enters the blood, where it competes with oxygen for hemoglobin molecules. Carbon monoxide, having a double chemical bond, binds to hemoglobin more firmly than an oxygen molecule. The more CO2 is in the air, the more hemoglobin molecules bind to it and the less oxygen reaches the body's cells. The ability of the blood to deliver oxygen to tissues is disrupted, vascular spasms are caused, a person’s immunological activity decreases, accompanied by headache, loss of consciousness and death. For these reasons, CO in elevated concentrations is a deadly poison.

CO disrupts phosphorus metabolism. Violation of nitrogen metabolism causes sotemia, changes in the content of plasma proteins, a decrease in the activity of blood cholinesterase and the level of vitamin B 6. Carbon monoxide affects carbohydrate metabolism, enhances the breakdown of glycogen in the liver, disrupting the utilization of glucose, increasing blood sugar levels. The entry of CO from the lungs into the blood is determined by the concentration of CO in the inhaled air and the duration of inhalation. CO is released mainly through the respiratory tract.

The central nervous system suffers most from poisoning. When inhaling a small concentration (up to 1 mg/l) - heaviness and a feeling of squeezing of the head, severe pain in the forehead and temples, dizziness, trembling, thirst, increased heart rate, nausea, vomiting, increased body temperature to 38-40 ° C. Weakness in the legs indicates that the action has spread to the spinal cord.

The extreme toxicity of CO, its lack of color and odor, as well as the very weak absorption of it by the activated carbon of a conventional gas mask make this gas especially dangerous.

Ammonia.

Ammonia- colorless gas with a pungent odor, melting point - 80°C, boiling point - 36°C, soluble in water, alcohol and a number of other organic solvents. Synthesized from nitrogen and hydrogen. In nature, it is formed during the decomposition of nitrogen-containing organic compounds.

Being in nature.

In nature, it is formed during the decomposition of nitrogen-containing organic compounds.

The pungent odor of ammonia has been known to man since prehistoric times, since this gas is formed in significant quantities during the rotting, decomposition and dry distillation of nitrogen-containing organic compounds, such as urea or proteins. It is possible that in the early stages of the Earth's evolution there was quite a lot of ammonia in its atmosphere. However, even now, tiny amounts of this gas can always be found in the air and in rainwater, since it is continuously formed during the decomposition of animal and plant proteins.

Anthropogenic sources of entry into the environment.

The main sources of ammonia emissions are nitrogen fertilizer plants, enterprises for the production of nitric acid and ammonium salts, refrigeration units, coke plants and livestock farms. In areas of technogenic pollution, ammonia concentrations reach values ​​of 0.015-0.057 mg/m 3, in control areas - 0.003-0.005 mg/m 3.

Effect on the human body.

This gas is toxic. A person is able to smell ammonia in the air already in an insignificant concentration - 0.0005 mg/l, when there is still no great danger to health. When the concentration increases 100 times (up to 0.05 mg/l), the irritating effect of ammonia on the mucous membrane of the eyes and upper respiratory tract is manifested, and even a reflex cessation of breathing is possible. Even a very healthy person can hardly withstand a concentration of 0.25 mg/l for an hour. Even higher concentrations cause chemical burns to the eyes and respiratory tract and become life-threatening. The external signs of ammonia poisoning can be quite unusual. In victims, for example, the hearing threshold sharply decreases: even not too loud sounds become unbearable and can cause convulsions. Ammonia poisoning also causes strong agitation, even violent delirium, and the consequences can be very severe - leading to a decrease in intelligence and personality changes. Obviously, ammonia can attack vital centers, so careful precautions must be taken when working with it.

Chronic exposure to sublethal doses of ammonia leads to autonomic disorders, increased excitability of the parasympathetic nervous system, complaints of weakness, malaise, runny nose, cough, and chest pain.

Substance hazard class - 4.

Poison gas is a toxic chemical substance that causes intoxication of the body and damage to internal organs and systems. Enters through the respiratory system, skin, and gastrointestinal tract.

List of poisonous gases depending on their toxicological effects:

1. Nerve agents – carbon monoxide, sarin.
2. Blisters – lewisite, mustard gas.
3. Asphyxiants - phosgene, diphosgene, chlorine.
4. Tear relievers – bromobenzyl cyanide, chloroacetophenone.
5. General exposure: hydrocyanic acid, cyanogen chloride.
6. Irritants – adamsite, CR, CS.
7. Psychotomimetic – BZ, LSD-25.

Let's consider the most dangerous gases, the mechanism of their destruction, and signs of poisoning in humans.

Sarin

Sarin is a toxic liquid substance that at a temperature of 20 °C it quickly evaporates and has a nerve-paralytic effect on the human body. As a gas, it is colorless and odorless and is most dangerous if inhaled.

Symptoms appear immediately upon exposure to the respiratory tract. The first signs of poisoning are difficulty breathing and constriction of the pupil.

Clinical manifestations:

• irritation of the nasal mucosa, liquid discharge;
• drooling, vomiting;
• chest tightness;
• shortness of breath, bluish skin;
• spasm of the bronchi and increased formation of mucus in them;
• pulmonary edema;
• severe cramps and pain in the abdomen.

If high concentration sarin vapor enters the body severe brain damage occurs within 1-2 minutes. A person cannot control the physiological functions of the body - involuntary bowel movements and urination. Convulsions and seizures appear. Coma develops followed by cardiac arrest.

Mustard gas

Mustard gas is mustard gas. This is a chemical compound with blister action. In liquid form, the substance has a mustard smell. It enters the body in two ways - by airborne droplets and by contact of liquid with skin. It tends to accumulate. Signs of poisoning appear after 2-8 hours.

Symptoms of gas intoxication by inhalation:

• damage to the mucous membrane of the eyes;
• lacrimation, photophobia, feeling of sand in the eyes;
• dryness and burning in the nose, then swelling of the nasopharynx with purulent discharge;
• laryngitis, tracheitis;
• bronchitis.

If the liquid gets into the eyes, it will cause blindness. In severe cases of mustard gas poisoning, pneumonia develops and death occurs on the 3-4th day from suffocation.

Symptoms of gas poisoning upon contact with the skin are redness followed by the formation of blisters containing serous fluid, skin lesions, ulcers, necrosis. The gas destroys cell membranes, disrupts carbohydrate metabolism, and partially destroys DNA and RNA.

Lewisite

Lewisite is a highly toxic substance, the vapors of which can penetrate chemical protective suits and gas masks. It is a brown liquid with a pungent odor. The gas is classified as a skin vesicant. Acts on the body instantly and has no latency period.

Symptoms of gas poisoning when the skin is affected develop within 5 minutes:

• pain and burning at the point of contact;
• inflammatory changes;
• painful redness;
• formation of bubbles, they quickly open;
• the appearance of erosions, which take several weeks to heal;
• in severe cases, when exposed to large concentrations of lewisite, deep ulcers form.

Symptoms when inhaling gas:

• damage to the mucous membrane of the nasopharynx, trachea, bronchi;
• fluid from the nose;
• sneezing, coughing;
• headache;
• nausea, vomiting;
• loss of voice;
• feeling of pressure in the chest, shortness of breath.

The mucous membrane of the eyes is highly sensitive to poisonous gas.. It becomes red, the eyelids swell, and lacrimation increases. A person experiences a burning sensation in the eyes. When liquid lewisite enters the gastrointestinal tract, the victim begins to drool profusely and vomit. Sharp pain in the abdominal cavity occurs. Internal organs are affected, and blood pressure drops sharply.

Hydrogen sulfide

Hydrogen sulfide is a colorless gas with a pungent odor of rotten eggs. In high concentrations the substance is very toxic. Entering the body by inhalation, symptoms of general intoxication develop - headache, dizziness, weakness. Hydrogen sulfide is quickly absorbed into the blood and affects the central nervous system.

Signs of gas poisoning:

• metallic taste in the mouth;
• paralysis of the nerve responsible for the sense of smell, so the victim immediately ceases to feel any odors;
• respiratory tract damage, pulmonary edema;
• severe cramps;
• coma.

Carbon monoxide

Carbon monoxide is a colorless poisonous substance, lighter than air. Entering the body through the respiratory tract, it is quickly absorbed into the blood and binds to hemoglobin. This blocks the transport of oxygen to all cells, oxygen starvation occurs, and cellular respiration stops.

Symptoms of carbon monoxide poisoning:

• dizziness and headache;
• rapid breathing and heartbeat, shortness of breath;
• noise in ears;
• impaired visual acuity, flickering in the eyes;
• skin redness;
• nausea, vomiting.

In severe poisoning, convulsions are observed. Symptoms preceding coma increase - a drop in blood pressure, severe weakness, loss of consciousness. In the absence of medical assistance, death occurs within 1 hour.

Phosgene

Phosgene is a colorless gas with the odor of rotting hay. The substance is dangerous if inhaled, the first signs of intoxication appear after 4-8 hours. At high concentrations, death occurs within 3 seconds. Gas entering the lungs destroys them, causing instant swelling.

Symptoms at different stages of poisoning:

1. Pulmonary edema begins to develop in the latent period, when the victim is unaware of poisoning. The first signals from the body are a sweet, cloying taste in the mouth, nausea. Sometimes there is vomiting. A person feels a sore throat, itching and burning in the nasopharynx. A cough reflex occurs, breathing and pulse are disrupted.
2. After the latent period, the victim’s condition deteriorates sharply. A severe cough appears and the person begins to choke. The skin and lips turn blue.
3. The stage of progressive deterioration is severe pressure in the chest, leading to suffocation, the respiratory rate increases to 70 per minute (normal 18). A lot of fluid and mucus forms in the lungs due to the decomposition of the alveoli. A person coughs up sputum containing blood. Breathing becomes impossible. 50% of the bcc (circulating blood volume) goes to the lungs and increases them. The weight of one lung can be 2.5 kg (the norm is 500-600 g).

In severe cases, death within 10-15 minutes. In case of moderate gas poisoning, death occurs within 2-3 days. Recovery can occur 2-3 weeks after poisoning, but this is rare due to infection.

Hydrocyanic acid

Hydrocyanic acid is a colorless, light and mobile liquid with a pronounced odor. It blocks the chain of oxygen movement through tissues, causing tissue hypoxia. The gas affects the nervous system, disrupting the innervation of organs.

Symptoms of respiratory poisoning:

• dyspnea;
• at the beginning of the development of the clinical picture, rapid breathing;
• with severe intoxication - respiratory depression and cessation.

Signs of the heart:

• slowing down heart beats;
• increased blood pressure;
• vasospasm;
• as symptoms increase - drop in pressure, increased heart rate, acute cardiovascular failure, cardiac arrest.

Poisonous gases are strong, fast-acting substances. To save a person, emergency resuscitation measures are necessary. If the outcome is favorable, the victim needs long-term rehabilitation treatment.

Ethylene (ethene) is a colorless gas with a very weak sweetish odor, slightly lighter than air, slightly soluble in water.

C 2 – C 4 (gases)

C 5 – C 17 (liquids)

C 18 – (solid)

Alkenes are insoluble in water, soluble in organic solvents (gasoline, benzene, etc.)

Lighter than water

As Mr increases, the melting and boiling points increase

The simplest alkene is ethylene - C2H4

The structural and electronic formulas of ethylene are:

In the ethylene molecule one undergoes hybridization s- and two p-orbitals of C atoms ( sp 2 -hybridization).

Thus, each C atom has three hybrid orbitals and one non-hybrid p-orbitals. Two of the hybrid orbitals of the C atoms mutually overlap and form between the C atoms

σ - bond. The remaining four hybrid orbitals of the C atoms overlap in the same plane with four s-orbitals of H atoms and also form four σ - bonds. Two non-hybrid p-orbitals of C atoms mutually overlap in a plane that is located perpendicular to the σ-bond plane, i.e. one is formed P- connection.

By it's nature P- connection is sharply different from σ - connection; P- the bond is less strong due to the overlap of electron clouds outside the plane of the molecule. Under the influence of reagents P- the connection is easily broken.

The ethylene molecule is symmetrical; the nuclei of all atoms are located in the same plane and bond angles are close to 120°; the distance between the centers of C atoms is 0.134 nm.

SP 2 – hybridization:

1) Flat trigonal structure

2) Angle – HCH - 120°

3) Bond length (-C=C-) – 0.134 nm

4) Connections - σ, P

5) Rotation relative to (-С=С-) connection is impossible

If atoms are connected by a double bond, then their rotation is impossible without electron clouds P- the connection was not opened.

1. Colorless gas, odorless. 2. Heavier than air, 3. Poisonous, 4. Highly soluble in water, 5. Poorly soluble in water, 6. Slightly lighter than air, 7. Exhibits acidic properties. 8. Non-salt-forming oxide. 9. Combines with blood hemoglobin, 10. Obtained from the decomposition of carbonates. 11. At high pressure it liquefies, forming “dry ice”, 12. Used to produce soda, 13. Used as gas fuel, 14. Used in the production of fruit waters, 15. Used in organic synthesis. 1. Colorless gas, odorless. 2. Heavier than air, 3. Poisonous, 4. Highly soluble in water, 5. Poorly soluble in water, 6. Slightly lighter than air, 7. Exhibits acidic properties. 8. Non-salt-forming oxide. 9. Combines with blood hemoglobin, 10. Obtained from the decomposition of carbonates. 11. At high pressure it liquefies, forming “dry ice”, 12. Used to produce soda, 13. Used as gas fuel, 14. Used in the production of fruit waters, 15. Used in organic synthesis.

Carbonic acid H 2 CO 3 Mr(H 2 CO 3) = =62 Carbonic acid H 2 CO 3 Mr(H 2 CO 3) = =62

Since carbonic acid is dibasic, it forms two types of salts: carbonates and bicarbonates (Na 2 CO 3, NaHCO 3). Carbonates of alkali metals and ammonium are highly soluble in water, carbonates of alkaline earth metals and some others are practically insoluble in water. Carbonates of aluminum, iron, and chromium cannot exist in aqueous solutions, as they undergo complete hydrolysis. Almost all hydrocarbonates are soluble in water. Since carbonic acid is dibasic, it forms two types of salts: carbonates and hydrocarbonates (Na 2 CO 3, NaHCO 3). Carbonates of alkali metals and ammonium are highly soluble in water, carbonates of alkaline earth metals and some others are practically insoluble in water. . Carbonates of aluminum, iron, and chromium cannot exist in aqueous solutions, as they undergo complete hydrolysis. Almost all bicarbonates are soluble in water

Na 2 CO 3 – Soda ash – used to produce alkalis, in glass production, and in everyday life as a detergent. NaHCO 3 - baking soda or drinking soda - is used in the food industry, for charging fire extinguishers, and in medicine for heartburn. (CuOH) 2 CO 3 – malachite – in pyrotechnics, for the production of mineral paints, in nature in the form of the mineral malachite (ornamental stone) CaCO 3 – chalk, limestone, marble – for the production of lime, marble as a finishing stone, in agriculture for liming soil K 2 CO 3 – potash – for making soap, refractory glass, in photography. Na 2 CO 3 *10H 2 O - crystalline sodium carbonate - consumed by the soap, glass, textile, paper, and oil industries. Na 2 CO 3 – Soda ash – used to produce alkalis, in glass production, and in everyday life as a detergent. NaHCO 3 - baking soda or drinking soda - is used in the food industry, for charging fire extinguishers, and in medicine for heartburn. (CuOH) 2 CO 3 – malachite – in pyrotechnics, for the production of mineral paints, in nature in the form of the mineral malachite (ornamental stone) CaCO 3 – chalk, limestone, marble – for the production of lime, marble as a finishing stone, in agriculture for liming soil K 2 CO 3 – potash – for making soap, refractory glass, in photography. Na 2 CO 3 *10H 2 O - crystalline sodium carbonate - consumed by the soap, glass, textile, paper, and oil industries.

1. Suspended solids

Suspended solids include dust, ash, soot, smoke, sulfates, and nitrates. Depending on their composition, they can be highly toxic and almost harmless. Suspended substances are formed as a result of the combustion of all types of fuel: during the operation of car engines and during production processes. When suspended particles penetrate the respiratory system, the respiratory and circulatory systems are disrupted. Inhaled particles affect both the respiratory tract directly and other organs due to the toxic effects of the components contained in the particles. The combination of high concentrations of suspended solids and sulfur dioxide is dangerous. People with chronic lung disorders, cardiovascular diseases, asthma, frequent colds, the elderly and children are especially sensitive to the effects of small suspended particles. Dust and aerosols not only make breathing difficult, but also lead to climate change because they reflect solar radiation and make it difficult for heat to escape from the Earth. For example, the so-called smog in densely populated southern cities reduces the transparency of the atmosphere by 2-5 times.

2. Nitrogen dioxide

A colorless, odorless, poisonous gas.

Nitrogen oxides enter the atmosphere from industrial enterprises, power plants, furnaces and boiler houses, as well as from vehicles. They can be formed and released into the atmosphere in large quantities during the production of mineral fertilizers. In the atmosphere, emissions of nitrogen oxides are transformed into nitrogen dioxide. It is a colorless, odorless, poisonous gas. Nitrogen dioxide is an important component of photochemical processes in the atmosphere associated with the formation of ozone in sunny weather. At low concentrations of nitrogen dioxide, breathing problems and coughing are observed. The World Health Organization has found that an average hourly concentration of nitrogen dioxide of 400 μg/m3 causes painful symptoms in asthma patients and other groups of people with hypersensitivity. With an average annual concentration of 30 mcg/m3, the number of children with rapid breathing, coughing and patients with bronchitis increases. Nitrogen dioxide reduces the body's resistance to disease, reduces hemoglobin in the blood, and irritates the respiratory tract. With prolonged inhalation of this gas, oxygen starvation of tissues occurs, especially in children. Causes respiratory and circulatory diseases and malignant neoplasms. Leads to exacerbation of various pulmonary and chronic diseases.

3. Carbon monoxide

A colorless, odorless gas.

The concentration of carbon monoxide II in urban air is greater than that of any other pollutant. However, since this gas is colorless, odorless, and tasteless, our senses are unable to detect it. The largest source of carbon monoxide in cities is motor vehicles. In most cities, over 90% of carbon monoxide enters the air due to incomplete combustion of carbon in motor fuel according to the reaction: 2C + O2 = 2CO. Complete combustion produces carbon dioxide as the final product: C + O2 = CO2. Another source of carbon monoxide is tobacco smoke, which is encountered not only by people who smoke, but also by their immediate environment. It has been proven that a smoker absorbs twice as much carbon monoxide as a non-smoker. Carbon monoxide is inhaled along with air or tobacco smoke and enters the blood, where it competes with oxygen for hemoglobin molecules. Carbon monoxide binds to hemoglobin molecules more strongly than oxygen. The more carbon monoxide there is in the air, the more hemoglobin binds to it and the less oxygen reaches the cells. The ability of the blood to deliver oxygen to tissues is impaired, vascular spasms are caused, and a person’s immunological activity is reduced. For this reason, carbon monoxide at elevated concentrations is a deadly poison. Carbon monoxide also enters the atmosphere from industrial enterprises as a result of incomplete combustion of fuel. A lot of carbon monoxide is contained in emissions from metallurgy and petrochemical enterprises. Inhaled in large quantities, carbon monoxide enters the blood, increases the amount of sugar in the blood, and weakens the supply of oxygen to the heart. In healthy people, this effect manifests itself in a decrease in the ability to endure physical activity. In people with chronic heart disease, it can affect the entire functioning of the body. When standing on a busy highway for 1-2 hours, some people with heart disease may experience various symptoms of deteriorating health.

4. Sulfur dioxide

Colorless gas with a pungent odor.

In low concentrations (20-30 mg/m3), sulfur dioxide creates an unpleasant taste in the mouth and irritates the mucous membranes of the eyes and respiratory tract. It is released into the atmosphere mainly as a result of the operation of thermal power plants (TPPs) during the combustion of brown coal and fuel oil, as well as sulfur-containing petroleum products and during the production of many metals from sulfur-containing ores - PbS, ZnS, CuS, NiS, MnS, etc. When coal or oil is burned, the sulfur it contains is oxidized, producing two compounds - sulfur dioxide and sulfur trioxide. When dissolved in water, sulfur dioxide forms acid rain, which destroys plants, acidifies the soil, and increases the acidity of lakes. Even with an average content of sulfur oxides in the air of about 100 μg/m3, which often occurs in cities, plants acquire a yellowish tint. Coniferous and deciduous forests are most sensitive to it. With a high content of SO2 in the air, pine trees dry out. It has been noted that respiratory tract diseases, such as bronchitis, become more frequent when the level of sulfur oxides in the air increases. Exposure to sulfur dioxide in concentrations above the MPC can cause respiratory dysfunction and a significant increase in various respiratory diseases; there is an effect on the mucous membranes, inflammation of the nasopharynx, trachea, bronchitis, cough, hoarseness and sore throat. Particularly high sensitivity to the effects of sulfur dioxide is observed in people with chronic respiratory disorders and asthma. When combined concentrations of sulfur dioxide and suspended particles (in the form of soot) on average per day are above 200 μg/m3, slight changes in lung activity are observed in adults and children.

5. Benz(a)pyrene

Benz(a)pyrene (BP) enters the atmosphere during the combustion of various types of fuel. A lot of BP is contained in emissions from non-ferrous and ferrous metallurgy, energy and construction industries. WHO has established an annual average value of 0.001 μg/m3 as the value above which adverse effects on human health, including the occurrence of malignant tumors, may be observed.

6. Lead

Lead air pollution is created by metallurgy, metalworking, electrical engineering, petrochemical and motor transport enterprises. Near highways, lead concentrations are 2-4 times higher than far from them. Lead affects people in many ways, including inhaling lead-containing air through food, water, and dust. 50% of this metal enters the body through the respiratory system. It accumulates in the body, bones and superficial tissues. Lead affects the kidneys, liver, nervous system and blood-forming organs. Has a mutagenic effect. Organic lead compounds disrupt metabolism. Lead compounds are especially dangerous for children's bodies, as they cause chronic brain diseases leading to mental retardation. The increase in vehicle traffic and the use of leaded gasoline is accompanied by an increase in lead emissions from vehicles.

7. Formaldehyde

Colorless gas with a pungent irritating odor.

It is part of many artificial materials: plywood, varnishes, cosmetics, disinfectants, and substances used in the household. Formaldehyde is found in harmful emissions from thermal power plants and other industrial furnaces. A certain amount of formaldehyde is formed even when smoking cigarettes. And finally, it is found everywhere in nature, even in the human body. Natural concentrations do not affect human health in any way, but high concentrations of formaldehyde of artificial origin are dangerous for him. They cause headaches, loss of attention, and pain in the eyes. The respiratory tract and lungs, mucous tissues of the gastrointestinal tract are damaged. Allergic reactions caused by formaldehyde disrupt the functioning of internal organs and cause chronic diseases. The genetic apparatus is also affected, which can cause the occurrence of cancerous tumors. Free formaldehyde inactivates a number of enzymes in organs and tissues, inhibits the synthesis of nucleic acids, and disrupts the metabolism of vitamin C. When some materials are burned, formaldehyde is formed. It is found, for example, in car exhaust fumes and cigarette smoke. Indoor MACs can easily be exceeded due to cigarette smoking alone.

8. Phenol

Colorless crystalline substances, less often high-boiling liquids with a characteristic strong odor.

Monatomic - strong nerve poisons that cause general poisoning of the body also through the skin, which has a cauterizing effect. Polyatomic - can cause skin diseases; with prolonged intake into the body, they can inhibit enzymes. The oxidation products of phenols are less toxic. Technical phenol is a red-brown, sometimes black, viscous liquid. Phenol is used mainly for the synthesis of phenol-formaldehyde and other resins and a number of aromatic compounds; for disinfection. Phenol and its derivatives are among the most dangerous toxic compounds contained in wastewater from a number of industries. Signs of phenolic poisoning are a state of excitement and an increase in motor activity, turning into convulsions, which indicate a dysfunction of the nervous system, and, first of all, the neuromuscular system. In case of chronic poisoning, irritation of the respiratory tract, indigestion, nausea, vomiting in the morning, general and muscle weakness, itching, irritability, and insomnia are observed.

9. Chlorine

Gas with an unpleasant and specific odor.

The main sources of chlorine exposure relevant to human health are industrial emissions. Chlorine is corrosive to most building materials, as well as fabrics. Technological systems containing chlorine are kept closed. Exposure is observed primarily as a result of poor plant performance or accidental releases. When released, it spreads low on the ground. At low concentrations, the acute effects of chlorine exposure are usually limited to a pungent odor and mild eye and upper respiratory tract irritation. These phenomena disappear soon after the cessation of exposure. As concentrations increase, symptoms become more pronounced and the lower respiratory tract is involved in the process. In addition to the immediate irritation and associated cough, victims experience anxiety. Exposure to chlorine at higher concentrations is characterized by shortness of breath, cyanosis, vomiting, headache and increased agitation, especially in individuals prone to neurotic reactions. Tidal volume decreases and pulmonary edema may develop. With treatment, recovery usually occurs within 2-14 days. In more severe cases, complications such as infectious or aspiration pneumonia should be expected.

10. Arsenic

Arsenic and its compounds. - Calcium arsenate, sodium arsenite, Parisian green and other arsenic-containing compounds are used as pesticides for treating seeds and controlling agricultural pests; they are physiologically active and poisonous. The lethal dose when taken orally is 0.06-0.2 g. Its soluble compounds (anhydrides, arsenates and arsenites), when entering the gastrointestinal tract with water, are easily absorbed by the mucous membrane, enter the bloodstream, and are carried by it to all organs where and accumulate. Symptoms of arsenic poisoning are a metallic taste in the mouth, vomiting, severe abdominal pain. Later, convulsions, paralysis, death. The most well-known and widely available antidote for arsenic poisoning is milk, or rather the main milk protein, casein, which forms an insoluble compound with arsenic that is not absorbed into the blood. Chronic arsenic poisoning leads to loss of appetite and gastrointestinal diseases.

11. Carcinogens

Substances that have the ability to cause the development of malignant tumors.

Among the substances that enter the air and water environment, carcinogens are zinc, arsenic, lead, chromium, nitrates, iodine, benzene, DDT, and manganese. Molybdenum, lead and copper cause disorders of the central nervous system; bromine, barium and cadmium - kidney damage; mercury and iron are blood diseases.

12. Ozone (ground level)

A gaseous (under normal conditions) substance, the molecule of which consists of three oxygen atoms. In direct contact it acts as a strong oxidizing agent.

The destruction of the ozone layer leads to an increase in the flow of UV radiation onto the earth's surface, which leads to an increase in cases of skin cancer, cataracts and weakened immunity. Excessive ultraviolet exposure leads to an increase in the incidence of melanoma, the most dangerous type of skin cancer.

Ground-level ozone is not released directly into the air, but is produced by chemical reactions between nitrogen oxides (NOx) and volatile organic compounds (VOCs) in the presence of solar radiation. Emissions from industrial enterprises and thermal power plants, vehicle exhaust, gasoline vapors and chemical solvents are the main sources of NOx and VOCs.

At the earth's surface level, ozone is a harmful pollutant. Ozone pollution poses a threat during the summer months as intense solar radiation and hot weather contribute to the formation of harmful concentrations of ozone in the air we breathe. Inhaling ozone can cause a number of health problems, including chest pain, coughing, throat irritation, and body flushing. It can worsen the condition of patients with bronchitis, emphysema and asthma. Ground-level ozone can impair lung function and lead to lung inflammation. Repeated exposure to high levels of ozone can cause scarring in the lungs.

13. Ammonia

Flammable gas. Burns in the presence of a constant source of fire. Vapors form explosive mixtures with air. Containers may explode when heated. Explosive mixtures form in empty containers.

Harmful if inhaled. The vapors are highly irritating to the mucous membrane and skin and cause frostbite. Adsorbed by clothing.

In case of poisoning, a burning pain in the throat, severe cough, feeling of suffocation, burns of the eyes and skin, severe agitation, dizziness, nausea, stomach pain, vomiting, spasm of the glottis, suffocation, possible delirium, loss of consciousness, convulsions and death ( due to cardiac weakness or respiratory arrest). Death most often occurs within a few hours or days as a result of swelling of the larynx or lungs.

14. Hydrogen sulfide

Colorless gas with an unpleasant odor. Heavier than air. Let's dissolve in water. Accumulates in low areas of the surface, basements, tunnels.

Flammable gas. Vapors form explosive mixtures with air. Lights easily and burns with a pale blue flame.

Symptoms of poisoning: headache, irritation in the nose, metallic taste in the mouth, nausea, vomiting, cold sweat, palpitations, squeezing of the head, fainting, chest pain, choking, burning eyes, lacrimation, photophobia, can be fatal if inhaled.

15. Hydrogen fluoride

A colorless, low-boiling liquid or gas with a pungent odor. Heavier than air. Let's dissolve in water. It smokes in the air. Corrosive. Accumulates in low parts of the surface, basements, tunnels.

Not flammable. Releases flammable gas on contact with metals. Poisonous if taken orally. Possibly fatal if inhaled. Acts through damaged skin. The vapors are highly irritating to mucous membranes and skin. Contact with liquid causes burns to the skin and eyes.

Symptoms of poisoning: irritation and dryness of the nasal mucosa, sneezing, coughing, choking, nausea, vomiting, loss of consciousness, redness and itching of the skin.

16. Hydrogen chloride

Colorless gas with a pungent odor. In the air, interacting with water vapor, it forms a white fog of hydrochloric acid. Extremely soluble in water.

Hydrogen chloride has strong acidic properties. Reacts with most metals to form salts and release hydrogen gas.

Due to the extremely high solubility in water, poisoning usually occurs not with hydrogen chloride gas, but with a mist of hydrochloric acid. The main affected area is the upper respiratory tract, where most of the acid is neutralized. It is necessary to take into account the contamination of emissions with other substances, as well as the possibility of the formation of toxic reagents, especially arsine (AsH3).

17. Sulfuric acid

Oily liquid, colorless and odorless. One of the strongest acids. Produced by burning sulfur or sulfur-rich ores; the resulting sulfur dioxide is oxidized into anhydrous sulfur gas, which is absorbed by water to form sulfuric acid.

Sulfuric acid is one of the main products of the chemical industry. It is used for the production of mineral fertilizers (superphosphate, ammonium sulfate), various acids and salts, medicines and detergents, dyes, artificial fibers, and explosives.

It is used in metallurgy (decomposition of ores, such as uranium), for the purification of petroleum products, as a desiccant, etc.
It has a destructive effect on plant and animal tissues and substances, taking away their water, as a result of which they become charred.

18. Copper

Copper is a yellow-orange metal with a red tint and has high thermal and electrical conductivity.

Copper enters the environment from copper plating, brassing, bronzing baths, from copper coating removal baths and from etching baths of rolled copper and tombac, as well as during etching of printed circuit boards.

Copper affects the respiratory system, metabolism, allergen. With the simultaneous presence of heavy metals, three types of toxic properties are possible:

1. Synergism - the effect of action is greater than the total effect (cadmium in combination with zinc and cyanides);

2. Antagonism - the effect of an action is less than the total effect. For example, with the combined presence of copper and zinc, the toxicity of the mixture is reduced by 60-70%;

3. Additive - the action effect is equal to the sum of the toxicity effects of each of the heavy metals (a mixture of zinc and copper sulfides in low concentrations).

Copper metal vapors generated during the production of various alloys can enter the body with inhaled air and cause poisoning.

Absorption of copper compounds from the stomach into the blood occurs slowly. Since copper salts entering the stomach cause vomiting, they can be excreted from the stomach with vomit. Therefore, only small amounts of copper enter the blood from the stomach. When copper compounds enter the stomach, its functions may be disrupted and diarrhea may appear. After copper compounds are absorbed into the blood, they act on the capillaries, causing hemolysis, liver and kidney damage. When concentrated solutions of copper salts are introduced into the eyes in the form of drops, conjunctivitis may develop and damage to the cornea may occur.

19. Cadmium

Cadmium is a silver-white, shimmering blue metal, soft and fusible, which fades in air due to the formation of a protective oxide film.

The metal itself is non-toxic, but soluble cadmium compounds are extremely toxic. Moreover, any way of their entry into the body and in any condition (solution, dust, smoke, fog) is dangerous. In terms of toxicity, cadmium is not inferior to mercury and arsenic. Cadmium compounds have a depressant effect on the nervous system, affect the respiratory tract and cause changes in internal organs.

Large concentrations of cadmium can lead to acute poisoning: a minute stay in a room containing 2500 mg/m 3 of its compounds leads to death. In acute poisoning, symptoms of damage do not develop immediately, but after a certain latent period, which can last from 1-2 to 30-40 hours.

Despite its toxicity, cadmium has been proven to be a trace element vital for the development of living organisms.

20. Beryllium

Beryllium is the second lightest known metal. Due to their properties, beryllium and its alloys are widely used in industry. Some fuels, such as coal and oil, contain parts of beryllium, so this element is found in the air and in the living tissues of urban residents. Burning waste and garbage is also a source of air pollution. Basically, beryllium can be ingested through inhalation of dust or fumes, as well as through skin contact.

The toxicity of beryllium has been known since the 30s of the twentieth century, and since the 50s it has been recognized as dangerous to people and the environment. Thanks to the safety measures taken, acute forms of beryliosis have practically disappeared, but chronic cases are still being recorded. A distinctive feature of chronic diseases caused by beryllium (CBD) is their ability to masquerade as sarcoidosis (Beck's disease), so CBD is very difficult to identify.

Sarcoidosis causes granulomas in the lungs, liver, spleen and heart. Skin disease develops and a strong weakening of the immune system is observed. In its chronic form, beryliosis is characterized by severe shortness of breath, cough, fatigue, chest pain, weight loss, increased sweating, fever and decreased appetite. The time elapsed from first contact with beryllium to the appearance of clinical signs can vary from several months to several decades. At an early stage, the disease is accompanied by a violation of air exchange in the lungs, and at a late stage there is an almost complete cessation of air exchange.

Likewise, acute pneumonitis, chronic pneumonitis, sarcoidosis, and acute beryliosis - all of them are the most dangerous forms of chronic disease.

21. Mercury

Mercury is a silvery-white heavy metal, the only metal that is liquid under normal conditions.
Poisoning by mercury and its compounds is possible in mercury mines and factories, during the production of certain measuring instruments, lamps, pharmaceuticals, insectofungicides, etc.

The main danger is posed by metallic mercury vapor, the release of which from open surfaces increases with increasing air temperature. When inhaled, mercury enters the bloodstream. In the body, mercury circulates in the blood, combining with proteins; partially deposited in the liver, kidneys, spleen, brain tissue, etc. The toxic effect is associated with blocking sulfhydryl groups of tissue proteins, disruption of brain activity (primarily the hypothalamus). Mercury is excreted from the body through the kidneys, intestines, sweat glands, etc.

Acute poisoning with mercury and its vapors is rare. In chronic poisoning, emotional instability, irritability, decreased performance, sleep disturbance, trembling of fingers, decreased sense of smell, and headaches are observed. A characteristic sign of poisoning is the appearance of a blue-black border along the edge of the gums; gum damage (looseness, bleeding) can lead to gingivitis and stomatitis. In case of poisoning with organic compounds of mercury (diethylmercury phosphate, diethylmercury, ethylmercuric chloride), signs of simultaneous damage to the central nervous (encephalo-polyneuritis) and cardiovascular systems, stomach, liver, and kidneys predominate.

22. Zinc

Zinc is a bluish-white metal. It plays an important role in the synthesis of nucleic acids and proteins. The element is necessary for stabilizing the structure of DNA, RNA, ribosomes, plays an important role in the translation process and is indispensable at many key stages of gene expression.

Elevated concentrations of zinc have a toxic effect on living organisms. In humans, they cause nausea, vomiting, respiratory failure, pulmonary fibrosis, and are a carcinogen. Excess zinc in plants occurs in areas of industrial soil pollution, as well as with improper use of zinc-containing fertilizers.