Nitrogen (Nitrogenium, N)is a chemical element V of groups of periodic system of elements of Mendeleyev. Serial number 7; at. weight 14,0067; valence from -3 to +5. Nitrogen is a colorless gas without smell and taste, consisting of diatomic molecules (N2), chemically inactive. In a free form nitrogen is the main air mass (78,09 about. %). In soil nitrogen contained in the form of mineral salts. In a related view is included in the tissues of plants and animals. In nature there is a constant nitrogen cycle: plants get nitrogen from the soil in the form of salts, organic nitrogenous substances of plants are food for animals, assimilative vegetable proteins. In the process of metabolism in the organism of animal protein is broken down, their degradation products get into the soil and water, where further decomposition under the influence of microorganisms leads to the formation of ammonia, which can be used by plants directly or after transformation into nitrogenous salts. Great importance in the nitrogen cycle is the activity of common nitrogen-fixing bacteriathat use direct atmospheric nitrogen. Being one of the key elements for building protein, nitrogen is the most important biogenic element involved in the main processes of vital activity of an organism.
Under normal conditions, the nitrogen in the body do not have. With the increased partial pressure of nitrogen appears suffocation due to the reduced partial pressure of oxygen in the lungs, this is manifested drug action of nitrogen: General arousal disorder coordination, dizziness, automatic movements (see Decompression illness (DCI).
Toxicological significance are many compounds nitrogen, commonly found in industrial environments. With hydrogen nitrogen to form ammonia, hydrazine, attestation acid. With the oxygen, the nitrogen forms oxides: nitrous oxide, carbon monoxide, dioxide, trioxide, or anhydride of nitrous acid, and pjatiokisi, or anhydride of nitric acid.
Maximum permissible concentration of nitrogen oxides in the air of working premises (in terms of pjatiokisi) 5 mg/m3.
Important Toxicological significance and more complex nitrogen compounds- alkaloids, amino - and nitro compounds, fatty and aromatic series, cyanide compounds. All these substances are very toxic and can cause acute and chronic poisonings (see Amines, nitro compounds).
Symptoms of poisoning compounds of nitrogen. Nitrous oxide acts as a narcotizing means; in overdose after loss of consciousness and sensitivity can occur asphyxia and paralysis of the respiratory center. Acute poisoning nitrous oxide comes intoxicated with euphoria, then headache, vasodilatation. For poisoning nitric oxide characteristic grey-blue colour of the mucous membranes and skin, loss of consciousness, coma, tachycardia, drop in blood pressure, blood becomes brown-chocolate color. In the administration of nitrogen dioxide occurs toxic pulmonary edema, beginning with cough, headache, followed by weakness, chest pain, shortness of breath, frothy sputum, cyanosis (blue of anoxemia); in some cases, swelling accompanied by a collapse, in which there are pale-grey colour of the skin and mucous membranes, the fall in blood pressure ("gray" type of anoxemia). Poisoning sodium nitrite is characterized by redness of the face, profuse sweating, fall in blood pressure, disorders of view and cardiac activity, the onset of coma.
First aid. In the administration of nitrous or nitric oxide make the victim to fresh air, give breathe Carbogen, inside the heart funds injected glucose intravenously (20-30 ml of 40% solution), if necessary - bloodletting.
In the administration of nitrogen dioxide - the same activities as in the administration of nitric oxide, oxygen therapy, 10% solution of chloride calcium intravenously (5 ml). When grey type of anoxemia bloodletting is contraindicated.
In the administration of sodium nitrite - washing stomach, Carbogen, drip of 5% solution of glucose, under the skin - isotonic solution of sodium chloride, tonics (camphor, caffeine, korazol), when ischemia breath - lobelias.
Symptoms of poisoning and first aid in the defeat of the skin nitric acid and ammonia poisoning - see Nitric acid, Ammonia.