Heavier than air (relative density 1.527). Soluble in water (1:2). At 0°C and a pressure of 30 atmospheres, as well as at ordinary temperature and pressure of 40 atmospheres, it condenses into a colorless liquid. One kilogram of liquid nitrous oxide produces 500 liters of gas. Nitrous oxide does not ignite, but supports combustion. Mixtures with ether, cyclopropane, chloroethyl in certain concentrations are explosive.

They use it by inhalation, mainly using balloons filled with nitrous oxide.

The rapid achievement of a state of euphoria turned “laughing gas” into a popular drug at various kinds of youth parties. Laughing gas has been distributed mainly in nightclubs since the summer of 2012.

According to the chief narcologist of the Ministry of Health of the Russian Federation, Evgeniy Bryun, doctors may still be addicted to the use of this substance, and how dependence on it occurs.

The head of Rospotrebnadzor, the chief state sanitary doctor of Russia, Gennady Onishchenko, said that the use of nitrous oxide in medical conditions is acceptable. “This is one of the most gentle anesthetics. But when it is used on a huge scale outside the walls of medical institutions for absolutely no reason, no one knows how it will affect.”

Presumably, the use of laughing gas can produce irreversible effects on the brain and nervous system. Even with a small concentration, it disorganizes mental activity, makes it difficult for muscles to work, and impairs vision and hearing.

Its use is only possible under the supervision of specialists who have undergone appropriate training. Without proper control and in its pure form (without “dilution” with oxygen), the use of laughing gas is deadly. If the volume of oxygen in the mixture with nitrous oxide is less than 20%, respiratory arrest may occur and the person will die.

Signs of nitrous oxide use:

With short-term use - stupid behavior, unreasonable uncontrollable laughter, dizziness, frequent headaches, frequent fainting and frequent loss of consciousness.

With long-term use - short-term amnesia, emotional instability, disturbance of thought processes, deterioration of hearing and touch, unsteady gait, slurred speech, gradual brain atrophy.

The material was prepared based on information from RIA Novosti and open sources

Today, it plays a significant role in the formation of smog and acid precipitation. Let's look at what this substance is and why it is dangerous for humans.

Nitrogen dioxide: formula, characteristics

Nitrogen dioxide - inorganic compound NO 2 composition. It is a yellow-brown gas. At low temperatures it becomes colorless. At temperatures higher than 150°C, the dioxide dissociates into nitric oxide and oxygen.

This compound is characterized by a specific odor, which in significant concentrations becomes suffocating. Has high chemical activity. Interacts with non-metals, in reactions with which it acts as an oxidizing agent. On contact with water it turns into nitric acid, and in an alkaline environment it forms nitrites and nitrates.

Obtaining nitrogen dioxide in laboratory conditions

In laboratories, nitrogen dioxide is mainly produced by reacting concentrated nitric acid with copper:

Cu + 4HNO 3 → (CuNO 3) 2 + 2NO 2 + 2H 2 O.

In addition, the compound is formed during the thermal decomposition of lead nitrate.

In industrial conditions it is used in the production of nitric and sulfuric acids, as a nitrating agent for the production of anhydrous nitrates and as an oxidizing agent in mixed explosives and liquid rocket fuel.

Anthropogenic sources of nitrogen dioxide emissions

More than 90% of total nitrogen oxide emissions end up in air environment when burned various types fuel. The initial form is NO, which, while in the air, is oxidized by oxygen at high temperatures to NO 2.

The main sources influencing the release of nitrogen dioxide into the atmosphere:

• vehicles whose exhaust gases make the greatest contribution to the concentration of substances in urban air;
• thermal power plants;
• industrial enterprises, in particular, the oil and metallurgical industries, as well as factories producing nitric acid and various fertilizers;
• burning of solid waste (in particular, in waste incineration plants).

The brown tint of the gas allows it to be observed visually in the air big cities, where the daily dynamics of nitrogen oxide concentrations is quite closely related to the intensity of vehicle traffic and solar radiation. In the morning hours, an increase in the number of cars on the roads leads to a noticeable increase in the content of nitrogen monoxide, which, as the sun rises, turns into NO 2 as a result of photochemical oxidation. Emissions from some chemical plants are also brown, which is why they are called “fox tails.” They are especially noticeable in summer.

Sanitary and hygienic characteristics

Among all the oxides of the NOx group, the most dangerous for environment and humans is precisely nitrogen dioxide. Hazard class - second. This means that NO 2 is a highly hazardous substance. Maximum permissible single-time concentration (MPC) of nitrogen dioxide in the air settlements equal to 0.085 mg/m 3, average daily - 0.04.

Other standard values ​​have been established for working area air. Thus, the value of the maximum permissible concentration (MPC r.z.) is 2 mg/m 3 of the compound (nitrogen dioxide). Hazard class - third. That is, NO 2 is classified as hazardous substances.

Nitrogen dioxide: effects on humans

The substance is characterized by high toxicity. Nitrogen dioxide in the air, even in relatively small concentrations, can lead to significant changes in the human body. It is an acute irritant and is also characterized by general toxic effect. Affects mainly the organs of the respiratory system. Depending on the concentration, various effects are observed - from mild irritation of the mucous membranes of the eyes and nose to pulmonary edema. It can also lead to changes in blood composition, in particular, it helps to reduce hemoglobin content. Below we will take a closer look at some of the effects that nitrogen dioxide can cause in humans.

Effect on the sense of smell

Even if the concentration of nitrogen dioxide is low, people can smell its specific smell. The threshold value for gas fixation in the air for humans is considered to be 0.23 mg per cubic meter. meter. But when you inhale nitrogen dioxide for 10 minutes, you lose the ability to smell it, which indicates a negative effect on the sense of smell, expressed in its weakening. In this case, unpleasant dryness in the throat and irritation of the mucous membranes are observed, which disappear at a concentration exceeding the detection threshold by 15 times. However, other, more serious symptoms take their place, meaning negative impact nitrogen dioxide on the respiratory system.

Effect of nitrogen dioxide on vision

One of the consequences of complex effects on mucous membranes is a deterioration in a person’s ability to see at dusk. The ability to adapt to the absence of light is lost. The threshold concentration for changes in light sensitivity of the eye is 0.14 mg per cubic meter. meter. Considering that the value of olfactory perception is almost twice as high, we can talk about the ability of the gas to have a negative impact and yet remain unnoticed.

Effect on the respiratory system

At relatively low concentrations, nitrogen dioxide in the atmosphere can impair breathing. So, already when its content in the air is 0.056 mg per cubic meter. meter in a healthy person there is an increase in airway resistance. According to information from the World Health Organization, in people suffering from chronic diseases of the respiratory system, these symptoms are observed even when the NO 2 content in the air is equal to 0.04 mg per cubic meter. meter.

Pulmonary edema may result from exposure to high concentrations of nitrogen oxides. This is explained as follows. When entering the body and interacting with moisture, nitrogen dioxide and nitrogen oxide form nitrogenous and nitric acid, corroding the walls of the alveoli of the lungs. They, like blood capillaries, become easily permeable. As a result, blood serum enters the lung cavity. When inhaled, air and liquid form foam, which disrupts normal gas exchange, leading to pulmonary edema.

With prolonged exposure to nitrogen oxides, a person becomes more susceptible to pathogens that cause respiratory diseases. The resistance of the lungs to bacteria worsens, the alveoli and cells in the roots of the bronchi expand, bronchitis, pneumonia, etc. are more common.

People with heart disease and chronic respiratory disease are more likely to develop complications from short-term respiratory infections because they are more sensitive to the direct effects of nitrogen dioxide.

Effect on humans: other consequences

Nitrous acid, formed when interacting with moisture in the respiratory tract, reacts with alkaline components of tissues, resulting in nitrites and nitrates. Exposure to these substances causes a number of negative consequences. Thus, nitrites, being absorbed into the blood, lead to depression of the central nervous system, the formation of methemoglobin, hemolysis, bilirubinemia, dilate blood vessels, reduce blood pressure, etc. Nitrates, when in the intestines, can be transformed into carcinogenic substances - nitrosamines.

According to a number of literary sources, the effect of nitrogen dioxide on the human body reduces its resistance to diseases and leads to oxygen starvation of tissues. This is especially acute in children. Nitrogen dioxide also increases the effect of carcinogenic substances and the resulting occurrence of malignant neoplasms.

Some researchers associate increased mortality from cancer and cardiovascular diseases in certain areas with high levels of NO 2 in the air.

Chronic nitrogen dioxide poisoning

Long-term work in the presence of nitrogen dioxide in the air leads to the development of chronic diseases, the most common of which are: tracheitis, bronchitis, perforation of the nasal septum, pneumosclerosis, etc.

In people who worked for 3-5 years with a NO 2 content in the air of the working area of ​​0.8-5 mg per cubic meter. meter, chronic bronchitis, inflammatory changes in the mucous membrane of the gums, pneumosclerosis complicated by asthmatic attacks, and bronchiectasis were observed. In addition, there was an increase in the maximum osmotic resistance of erythrocytes, acceleration of blood clotting, a tendency to hypotension, granulocytosis, a decrease in catalase activity, sugar content and the level of globulins and albumins in the blood.

In children living in areas where nitrogen dioxide was present in concentrations of 0.117-0.205 mg per cubic meter. meter, changes in forced expiratory volume and an increase in morbidity were detected. In addition, changes in the configuration of lymphocytes and monocytes and an increase in the resistance of erythrocytes were observed in blood smears.

Conclusions

As we see from the above material, nitrogen dioxide in atmospheric air can have an extremely negative effect on the human body. Unfortunately, the excess permissible concentrations of this substance in the air is not uncommon. Therefore, issues related to the development of measures aimed at reducing nitrogen dioxide emissions into the atmosphere, which have both environmental and sanitary-hygienic significance, are quite relevant today.

How chemical element nitrogen is necessary for the existence of any living organism, since it participates in the reactions of energy supply, protein synthesis and nucleic acids. In total, when calculated on a dry weight basis, it makes up 2% of the human body, that is, along with carbon, oxygen and hydrogen, it is an important macronutrient.

In nature, this inert gas and its compounds are also found everywhere. Its content is high in plants, soil, and mineral deposits. But, being completely harmless in normal conditions, sometimes it can lead to serious intoxication.

Reasons for the development of nitrogen intoxication

The most stable form is the diatomic gas molecule N2, which makes up almost 80% of the Earth's atmosphere, and with each breath a large dose enters the human body. And if under normal conditions, with normal atmospheric pressure and sufficient oxygen content, due to its chemical inertness, it has practically no effect on the state of the body, then when some parameters change external environment its entry into the body can cause nitrogen poisoning.

Intoxication in the overwhelming majority of cases is associated with violation of safety precautions when working with this chemical. It can develop in the following situations:

• accidents in industries where gas is used, or damage to the integrity of containers during its transportation;
• accidental ingestion of gas into the body when working with it in a chemical laboratory;
• diving of divers to great depths, during which there is a risk of developing deep-seated illness;
• use of asphyxiating gas during hostilities.

The effect of nitrogen on the human body

The higher the nitrogen concentration and part pressure in the inhaled air, the stronger its toxic effect. For divers diving to great depths, the concentration of nitrogen in gas cylinders is sufficient that under the influence of high pressure (hyperbarium) the solubility of this gas in the blood increases. The risk of developing deep-seated disease is especially high when quickly diving to a depth of 25-28 meters, as well as if the diver has an individual high sensitivity to gas.

If you accidentally inhale air with excess nitrogen (industrial accidents, non-compliance with safety rules), it begins to act in the body as an asphyxiant, that is, it exhibits a suffocating effect. By displacing oxygen from the body, it leads to hypoxia and the development of respiratory failure.

The gas has a high ability to dissolve in fats, for this reason its molecules “stick” to cell membranes, consisting mostly of lipids, and thereby interfere with vital processes. It has the most pronounced destructive effect on the nervous system.

First, the work of the inhibitory neurons of the brain is blocked, which causes the narcotic effect of the gas - the so-called nitrogen intoxication appears. Subsequently, a toxic effect develops, in which the conduction of nerve impulses in other types of neurons is disrupted. The gas also harms the respiratory tract, reducing the activity of the alveoli.

The severity of intoxication directly depends on the concentration of oxygen in the inhaled air. If nitrogen accidentally enters an environment where the oxygen concentration is less than 6–7%, a few breaths are enough for the partial pressure of oxygen in the blood to drop to a critical level. When inhaling pure nitrogen, a person instantly loses consciousness and can die within 3-4 minutes of being in an atmosphere dominated by an inert gas.

Symptoms of poisoning

Nitrogen is a gas that has neither color nor odor, so it is very difficult to timely assess the risk of poisoning without special measuring instruments. The situation is also aggravated by the slow development of signs of intoxication: at first, a person may simply not notice how his body is losing oxygen, and poisoning occurs gradually over quite a long time.

Main symptoms of nitrogen poisoning:

• First of all, a cough appears, which is then accompanied by pain in the chest;
• at the beginning of the intoxication process, attacks of euphoria, causeless gaiety and motor disinhibition may appear;
• after some time, euphoria gives way to apathy, severe weakness, tremors of the limbs and a feeling of fear arise;
• symptoms may subside and increase again, while poisoning of the body continues;
• the skin takes on a bluish tint;
• body temperature rises, cough is mixed with blood or foam;
• with the development of pulmonary edema, attacks of suffocation are observed.

Death is possible from inhalation of pure nitrogen or from prolonged exposure to an atmosphere containing at least 90% inert gas.

Death most often occurs as a result of severe respiratory failure or oxygen deprivation of the brain.

First aid and treatment in case of injury

The life of the victim depends on the speed of actions of those around him, since he is often unable to help himself due to the development of nitrogen intoxication or fainting. Necessary:

1. Remove the person from the area of ​​high nitrogen concentration. In the event of an accident at an enterprise or during military use of gas, put on a gas mask or respirator on yourself, then on the injured person.
2. Call for medical help.
3. Provide oxygen to the poisoned person, loosen tight clothing, and untie the tie.
4. After the patient regains consciousness, give him plenty of fluids (water or sweet tea).

If a diver is intoxicated, it is necessary to slowly rise to the surface, check his pulse and breathing, provide him with oxygen, warmth and immobility.

Further assistance is provided by specialists in a hospital setting and under monitoring of vital signs. Actions are aimed at reducing the amount of inert gas in the body. An oxygen mask is used, glucose is administered intravenously, and if pulmonary edema develops, a calcium chloride solution is administered. If cardiac activity is impaired, a 10% caffeine solution and other vascular agents are injected subcutaneously.

It is important to remember that you should not refuse medical care or hospitalization even with mild nitrogen poisoning. Despite apparent well-being, disturbances may occur in the body that can lead to serious consequences.

Consequences and prevention

If assistance is provided in a timely manner, the chances of avoiding complications are quite high. However, severe intoxication can provoke further development of pathological conditions in a person, which include:

• diseases of the gastrointestinal tract and respiratory tract;
• blood clotting disorder;
• difficulty in gas exchange in the alveoli;
• disturbances in the functioning of the heart.

In some cases, long-term symptomatic therapy in a hospital setting is required.

To prevent gas poisoning, it is necessary to prevent violations of safety precautions in activities related to it. Work with nitrogenous fertilizers must be carried out in personal protective equipment. Industrial enterprises that use nitrogen compounds must be equipped with gas masks, and workers must be provided with safe working conditions.

Diving enthusiasts need to carefully monitor their condition when slowly diving to depth. It is recommended not to dive alone, especially if you are sensitive to nitrogen.

Nitrogen dioxide is a rather dangerous substance; accordingly, it has an adverse effect on various living systems.

Exposure to NO 2 on humans: Nitrogen dioxide strongly irritates the mucous membranes of the respiratory tract. Inhalation of the toxic fumes of this substance can lead to serious poisoning. Nitrogen dioxide causes sensory, functional and pathological effects. Let's look at some of them. Sensory effects include olfactory and visual reactions of the body to the effects of NO 2. Even at low concentrations of only 0.23 mg/m3, a person feels the presence of this gas. This concentration is the detection threshold for nitrogen dioxide. However, the body's ability to detect NO 2 disappears after 10 minutes of inhalation, but the throat feels dry and sore. Although these signs also disappear with prolonged exposure to gas at a concentration 15 times higher than the detection threshold. Thus, NO 2 weakens the sense of smell (4).

But nitrogen dioxide affects not only the sense of smell, but also weakens night vision - the eye's ability to adapt to darkness. This effect is observed at a concentration of 0.14 mg/m3, which is, accordingly, below the detection threshold (4).

The functional effect caused by nitrogen dioxide is increased airway resistance. In other words, NO 2 causes an increase in the effort spent on breathing. This reaction was observed in healthy people with a NO 2 concentration of only 0.056 mg/m3, which is four times lower than the detection threshold. And people with chronic lung diseases experience difficulty breathing even at a concentration of 0.038 mg/m3 (2).

The pathological effects are that NO 2 makes a person more susceptible to pathogens that cause respiratory diseases. People exposed to high concentrations of nitrogen dioxide are more likely to experience upper respiratory tract catarrh, bronchitis, and pneumonia. In addition, nitrogen dioxide itself can cause respiratory diseases. Once in the human body, NO 2 upon contact with moisture forms nitrous and nitric acids, which corrode the walls of the alveoli of the lungs. In this case, the walls of the alveoli and blood capillaries become so permeable that they allow blood serum to pass into the lung cavity. The inhaled air dissolves in this liquid, forming foam that prevents further gas exchange. Pulmonary edema occurs, which often leads to death. Long-term exposure to nitrogen oxides causes dilation of cells in the bronchial roots (thin branches of the airways of the alveoli), deterioration of the lungs' resistance to bacteria, and dilation of the alveoli. Some researchers believe that areas with high levels of nitrogen dioxide in the atmosphere experience increased mortality from heart disease and cancer (3).

People with chronic respiratory diseases (emphysema, asthma) and cardiovascular diseases may be more sensitive to the direct effects of NO 2 . They are more likely to develop complications (eg, pneumonia) from short-term respiratory infections (3).

In addition, nitrogen dioxide escaping into the atmosphere poses a serious danger to ecological situation, since it is capable of causing acid rain and be one of the components of photochemical smog. Both of these phenomena cause enormous damage to the health of the population and all the layers of the earth (2).

Impact of NO 2 on plants: the direct effect of NO 2 on plants is determined visually by the yellowing or browning of leaves and needles, which occurs as a result of chlorophyll oxidation. The oxidation of fatty acids in plants, occurring simultaneously with the oxidation of chlorophyll, also leads to membrane destruction and necrosis (6).

Formed in the cells nitrous acid has a mutagenic effect. The negative biological effect of NO 2 on plants is manifested in discoloration of leaves, wilting of flowers, cessation of fruiting and growth. This effect is explained by the formation of acids when nitrogen oxides dissolve in intercellular and intracellular fluids (3).

Botanists believe that the initial symptoms of nitrogen dioxide damage to plants are a random distribution of gray-green discolored spots. These spots gradually become rougher, dry out and turn white. NO 2 is toxic at a concentration of 3 ppm. For comparison: sulfur dioxide causes plant damage at higher concentrations (5 ppm) (5). Plant growth disturbances when exposed to NO 2 are observed at concentrations of 0.35 mg/m3 and higher. This value is the limiting concentration. The danger of damage to vegetation by nitrogen dioxide exists only in big cities and industrial areas, where the average NO 2 concentration is 0.2 - 0.3 mg/m3 (4). Plants are more resistant (compared to humans) to the effects of pure nitrogen dioxide. This is explained by the peculiarities of the assimilation of NO 2, which is reduced in chloroplasts and is included in amino acids as an NH 2 group. At a concentration of 0.17 - 0.18 mg/m3, nitrogen oxides are used by plants as fertilizers. This ability to metabolize NOx is not inherent in humans (2).

The Federal Service for Surveillance on Consumer Rights Protection and Human Welfare reports that the practice of using so-called laughing gas (especially among young people) has recently spread.

On the Internet you can find many offers for purchasing nitrous oxide for individual consumption by inhaling this gas. The goal is to obtain the so-called amusing effect. Such products, called “oxygen balls”, “Ibiza air”, are positioned as absolutely harmless, legal, affordable, fashionable, popular.

In fact, nitric oxide is unsafe for human life and health. Laughing gas has a faint pleasant odor and a sweetish taste; at a temperature of 37 °C it dissolves in the blood.

At high temperatures Nitrous oxide is a strong oxidizer; when mixed with hydrogen, ammonia, carbon dioxide and some flammable substances, it explodes.

In medicine, nitric oxide mixed with oxygen is used for anesthesia. The substance has a toxic effect; at high concentrations it causes suffocation due to the displacement of oxygen from the lungs.

Animal experiments have shown that exposure to nitric oxide in combination with oxygen (1:1; 8:2) for 6 days causes hematopoietic dysfunction and bone marrow hypoplasia in rats. Exposure of animals for 10 weeks leads to the death of some animals.

When the human body is exposed to gas mixtures containing from 20 to 50% NO, memory deteriorates, the ability of lung tissue to resist infection decreases, irritation of the eyes, nose and shortness of breath occur. With repeated exposure, addiction occurs and muscle performance decreases.

Inhalation for 5 minutes can cause bronchopneumonia, pulmonary edema, hemorrhage, rupture of the alveoli, pulmonary vascular thrombosis, degenerative changes in the liver, kidneys, brain, changes in the mucous membrane of the gums, pulmonary emphysema, pneumosclerosis.

The areas of application of nitrous oxide in its industrial production are as a medicine; for inhalation anesthesia (only for inpatient use in medical institutions) under the constant supervision of specialists.

Nitrous oxide high degree purification from impurities, intended for medical needs, does not cause irritation to the respiratory tract. During inhalation, it dissolves in the blood plasma, practically does not change and is not metabolized, and does not bind to hemoglobin. After stopping inhalation, nitrous oxide is released through the respiratory tract unchanged within 10-15 minutes.

Nitrous oxide is used mixed with oxygen using special devices for gas anesthesia. Usually they start with a mixture of 70-80% nitrous oxide and 30-20% oxygen, then the amount of oxygen is increased to 40-50%. For more complete muscle relaxation, myo-relaxants are used. This not only enhances muscle relaxation, but also improves the course of anesthesia. After stopping the supply of nitrous oxide, oxygen is continued to be given for 4-5 minutes to avoid hypoxia.

Nitrous oxide is used with caution as a means of therapeutic anesthesia. For a number of diseases - angina pectoris, myocardial infarction, diseases of the nervous system, chronic alcoholism, alcohol intoxication - its use is contraindicated. Excitement and hallucinations may occur when using this substance.

Nitrous oxide is also used for technical purposes, for example, for welding work, to improve technical characteristics internal combustion engines, in the food industry - for cooling, freezing and storing food products, as a preservative.

IN state register medicines The products of only a few enterprises are registered as a medicinal product with the trade name Nitrous Oxide.

According to the instructions for medical use, these drugs are dispensed only to medical institutions, which means they are inadmissible for free sale and inadmissible for individual purchase and consumption due to the possibility of violating the indications for use, methods of application and other requirements set out in the instructions.

In addition, metal liquefied gas cylinders under high pressure belong to the category of dangerous goods. Their transportation, storage and use require compliance with safety rules and the availability of special work permits for persons working with them.

Nitrous oxide as a commodity specific properties, intended for use exclusively for medical purposes in a hospital setting, as well as for technical and industrial purposes, cannot be freely sold on the consumer market. Retail sale of nitrous oxide is not provided and serves purposes that do not correspond to its true purpose, moreover, it poses a danger to life and health.

Storage, transportation, retail sale of nitrous oxide falls under Art. 14.2 of the Code Russian Federation on administrative offenses, This article concerns the illegal sale of goods, the free sale of which is prohibited or limited by law.