HYDROGEN SULPHIDE (H 2 S, hydrogen sulfide, sulphone) — the simplest compound of sulfur with hydrogen, it is poisonous, represents considerable professional harm.
C. it is very eurysynusic in the nature, it can be allocated from various natural sources, contains in volcanic gases, mineral and geothermal waters, oil, natural gas, is formed during the rotting of the organic residues containing sulfur (see), first of all — during the rotting of proteins (see. Rotting ); waters of the Black Sea at depths of St. 150 m are sated by S. Istochnik S. also industrial wastes, industrial smokes, drain waters, sewer devices, etc. are. In a small amount of S. contains in tobacco smoke. Villages use for receiving sulfur, sulphuric acid (see), in organic synthesis, and also for fight against page - x. wreckers.
The page represents colorless gas heavier than air, t°kip — 60,4 ° and t°pl — 85,6 °, with a characteristic smell of rotten eggs (at high concentration of S. this smell is not felt). It is sparingly soluble in water (about 3 volumes in 1 water volume at 20 °), in alcohol it is dissolved better. Oxidation, including burning, S. depending on amount of oxygen (its shortcoming or surplus) happens to formation of highly toxic sulfur dioxide or elemental sulfur (see).
Therefore water solution C. (so-called hydrogen-sulfide water) during the standing on air grows turbid owing to S.'s oxidation with release of elemental sulfur. Mixes C. with vozdukhokhm (at concentration of H2S 4,3—46,0 about. %) and with nitric oxide (at concentration of H2S 20—55 about. %) are explosive. In reactions with many substances C. shows properties of a strong reducer. The page is weak double-base to - that, a rka a cut in water (18 °) 7,04 (H2S <-> HS - + H + ) and 11,96 (HS - <-> S 2- + H + ), forming two rows of salts: sulfides — normal salts (e.g., Na2S sodium sulfide) and hydrosulphides — acid salts (e.g., NaHS sodium hydrosulphide).
The page is formed by direct synthesis of elements (H2 + S -> H2S). In a lab. S.'s conditions usually receive action by the diluted chamois to - you on iron sulfide (ferrous sulfide) or waters on aluminum sulfide. Natural gases, and also petroleum and coke oven gases are an industrial source of S. coke-chemical productions (see).
In air apply the test based on formation of lead sulfide, a deposit to qualitative test of S. to-rogo it is painted in black color, and also staining reactions with Sodium nitroprussidum (violet-red coloring) and with N, a N-dimetil-n-phenylenediamine and ferric chloride (formation of dye of methylene blue). Quantitatively S.'s maintenance in air define photometric — in the form of methylene blue or argentic sulfide, titrimetric — with the help iodine-azidnoy of reaction (sensitivity of 0,005 mg/m3) and other methods.
S. is strongly poisonous though its toxicity is often underestimated, napr, during the work in laboratory. It is the nervous poison in high concentration causing almost instant death from paralysis of a respiratory center. The page is irreversible inhibits ferriferous enzymes — tsitokhroma and, b and with (see. Tsitokhroma ) and cytochrome oxydase (KF 220.127.116.11), contacting iron in their molecules. It causes acute fabric hypoxia (see).
The page comes to an organism preferential through respiratory tracts, and also through skin. In an organism it quickly is oxidized to elemental sulfur and sulfates, to-rye are removed with urine; partially S. is allocated in not changed look through lungs.
S.'s poisonings arise generally as a result of violation of the rules of the accident prevention and production sanitation (see), imperfections tekhnol. processes, disturbance of tightness of the equipment, insufficient ventilation of production rooms, absence or failure of defensors. Degree of poisoning is influenced by S.'s concentration in inhaled air and duration of influence of poison. Women and teenagers are more sensitive to S., than men. At high concentration of S. danger of poisoning with it increases also because at the same time the smell is not felt by his person. The toxic effect of S. amplifies in the presence of hydrocarbons and carbon sulfur.
The threshold of feeling of a smell of S. is equal to 0,000012 — 0,00003 mg/l. Insignificant, but obviously notable smell note at concentration of Page 0,0014 — 0,0023 mg/l, a strong smell, but for got used to it not burdensome — at 0,003 mg/l, a considerable smell — at 0,004 mg/l, a smell burdensome even for got used to it — at 0,007 — 0,011 mg/l. At higher concentration of S. the smell becomes less strong and less unpleasant.
Diagnosis of poisonings of S. is based on data of the anamnesis, circumstances of poisoning and a wedge, a picture.
Hron. poisoning at early stages is characterized by diseases of eyes: pain in eyeglobes, a photophobia, dacryagogue, conjunctivitis, emergence of minor dot defects of a cornea. At later stages hron. S.'s poisonings observe rhinitises, laryngotracheitis, bronchitis, headaches, the general weakness, decrease in hearing, frequent dizzinesses, and also digestive disturbances, nausea, a diarrhea, emaciation, anemia, vascular and vegetative disturbances, skin rashes, an itch, a furunculosis, pustulous diseases of skin, on teeth the greenish-gray plaque appears. In blood — hypochromia anemia, an anisocytosis, a poikilocytosis, a neutrophilia.
At hron. S.'s poisoning symptomatic treatment.
Acute poisonings of S. divide on easy, moderately severe and heavy. At slight poisoning into the forefront symptoms of irritant action of S. act: burning in eyes, dacryagogue, a photophobia, a nictitating spasm, reddening of a conjunctiva, cold, irritation in a throat, cough. The reflex spasm of bronchial tubes is possible.
At moderately severe S.'s poisoning signs of resorptive effect of poison join these symptoms: headache, nausea, vomiting, dizziness, weakness, lack of coordination of movements, excitement or unconscious state. Tachycardia, hypotonia, cyanosis, ponosa, a frequent urination are possible. In urine of squirrels, cylinders. Body temperature is increased. Bronchitis or pneumonia can sometimes develop.
At a serious poisoning of S. at the victim note cyanosis, vomiting, disturbance of cardiovascular activity p breath, strong decrease in the ABP. In blood — a neutrophilia, relative increase in fraction of globulins, sometimes a hyperglobulia. At action on the person of very high concentration of S. (1 mg/l) develops fulminant, «apoplectic», the form of poisoning — instantly comes a loss of consciousness, there are spasms and there comes death from paralysis of a respiratory center or heart. If S.'s concentration in inhaled air is slightly lower, poisoning is shown in a convulsive and coma form. Sometimes the coma is replaced by motive excitement, there are hallucinations, then there comes the dream. After awakening note apathy, drowsiness, a dysmnesia. Can be effects of the postponed serious poisoning of S. decrease in intelligence up to weak-mindedness, paralyzes, hron. meningitis, dystrophy of a myocardium, etc.
First aid and emergency treatment
the Victim needs to be removed or taken out immediately on fresh air, to exempt from the clothes constraining breath, to protect from overcooling, to provide .poky, inhalation of oxygen is desirable. To wash out eyes warm water, a nose, a mouth and a throat to rinse 2% solution of Natrii hydrocarbonas. At fits of coughing — inside codeine, dionine. Morphine and its derivatives are contraindicated (danger of paralysis of a respiratory center). At the expressed signs of resorptive action of S. — intravenous injection of 20 — 30 ml of 0,25 — 0,5% methylene blue in 40% solution of glucose. Inhalation of chlorine (the scarf is moistened in solution of lime chloride), nitrites is recommended. At cardiovascular insufficiency subcutaneously enter 1 ml of 1% of solution of noradrenaline, 1 — 2 ml of 1% of solution of caffeine, 1 ml of Cordiaminum. At the developing fluid lungs — corresponding to lay down. actions; at a spasm of bronchial tubes, a glottis — an artificial respiration. The victim shall be as soon as possible hospitalized.
Measures of the prevention and prevention
Are necessary actions for the prevention of arrival of S. in air of production rooms and chemical laboratories: improvement tekhnol. processes, sealing oborudovannya, storage of reactants and work with them under draft, effective ventilation etc. Carrying out qualitative precautionary and current is of great importance sanitary inspection (see), timely and high-quality medical examinations (see. Medical examination ), treatment-and-prophylactic and recreational actions. Special attention shall be paid to the organization of gas-rescuing service (see), sanitary household to the device of workers, providing them by individual protection equipment — respirators (see), the filtering industrial gas masks (see), overalls (see. Clothes special ). The workers and technical officers occupied on productions where the contact with free S. is possible have the right for additional issue.
Examination of working capacity is defined by weight of poisoning. After slight poisoning of S. working capacity is recovered in several days or even several hours; the period of disability as a result of a serious poisoning can last more than a month. Further employment out of contact with the professional vrednostyami possessing irritant action shall be provided to victims.
Maximum allowable concentration of free S. in air of a working zone of 10 mg/m3, in the presence of hydrocarbons, napr, at oil refining with the high content of sulfur, 3 mg/m3.
Hydrogen sulfide in the medicolegal relation
S.'s Poisonings have character of accidents. During the opening of corpses of the dead note a picture of death from asphyxia (dark red liquid blood, a venous plethora of bodies, hypostasis and emphysema of lungs, punctulate hemorrhages on mucous membranes and under serous covers; blood and internals owing to an anoxia can have cerise coloring), from cavities and bodies — a smell of rotten eggs, especially we will feel this smell from lungs.
For with ud. - with the small duration of the posthumous period bodies place chemical detection of S. in a flask and close a stopper with the attached pieces of paper, one of to-rykh is moistened with solution of lead acetate, another — solution of red litmus or copper sulfate (for the proof of lack of ammonia and process of rotting). Bystry blackening of a piece of paper with lead acetate can serve as preliminary estimate of number of S. (a lot of, few, traces). For high-quality detection of S. the indicator pieces of paper moistened with divorced solution of Sodium nitroprussidum, podshchelochenny ammonia can serve. In the presence of S. such pieces of paper are painted in violet-red color.
Bibliography: Harmful substances in the industry, under the editorship of N. V. Lazarev and I. D. Gadaskina, t. 3, page 50, JI., 1977; E. A rebuzzing. Sanitary and chemical control of the air environment, page 124, etc., L., 1978; Occupational diseases, under the editorship of A. A. Letavet, etc., page 229, M., 1973; Ram and G. Kurs of inorganic chemistry, the lane with it., t. 1, page 701, M., 1972; The Guide to forensic medical examination of poisonings, under the editorship of R. V. Berezhny, etc., page 144, M., 1980; The Reference book on diagnosis and treatment of acute professional intoxications, under the editorship of G. I. Yevtushenko and K. G. Abramovich, page 154, Kiev, 1966; The Reference book on professional pathology, under the editorship of L. N. Gratsianskaya and V. E. Kovshilo, page 287, L., 1981; Sh in and y to about in and M. D. Toxicological chemistry, page 369, M., 1975; Shekhtman B. A., From ame-d And. And Mukhametova G. M. Occupational health in oil industry, page 180, M., 1979; Bittersohl G. Beitrag zum toxischen Wirkungsmeehanis-mus von Schwefelwasserstoff, Z. ges. Hyg., Bd 17, S. 305, 1971; Tomaszews-k a Z. Smiertelne zbiorowe zatrucie siar-kowodorem, Arch. Med. sad., t. 28, s. 55, 1978.
E. 3. Bronstein (court.), L. M. Karamova (gigabyte.), A. I. Tochilkin (chemical).