From Big Medical Encyclopedia

FORMALIN (a synonym formal) — water 37 — 40% the formalin containing up to 15% of methanol (for prevention of polymerization). T. apply to fixing of tissue, anatomic and microbiological specimens, at production of vaccines and serums as a desinfectant for washing of hands, medical tools, ware, rooms, clothes, and also at production of various deodorants, means for washing of skin at the increased perspiration, in production of plastic, chemical fibers, for a protravlivaniye of seeds, a tanning of skin, etc. Formalin possesses the action strong irritating, cauterizing and sensibilizing, is gepato-and nephrotoxic poison (see Poisonings). There are data that formaldehyde (see. Ant aldehyde) and T. show embriotropny properties and mutagen and oncogenous activity. T. on the productions connected with its receiving and use can be the reason of acute and chronic poisonings.

T. it is characterized by relative density at 18 °

[d]18 1,101 —1,076 4 18

and in coefficient of a refraction at 18 ° [p] ^

1,3766 — 1,3776, it represents colorless transparent liquid with a pungent smell, the size pH a cut fluctuates from 2,8 to 4,0. Sometimes in F. note emergence of a white deposit paraformaldega - yes — a dimeasure of formaldehyde; the deposit is dissolved at addition of water. T. define, using its ability inherent to all aldehydes (see), to recover silver salts (see), i.e. to give so-called silver mirror reaction and to paint solution fuksinsernisty to - you in red color (Schiff's reaction).

T. is a part of lysoformium (Lysoformium), soap solution of the formaldehyde (formalin 40 of h, soap of potash 40 h, 95% of alcohol of ethyl 20 h) applied to syringings in ginekol. to practice (1 — 4% water solutions), for disinfection of hands and rooms (1 — 3% solutions). For wiping of skin at the increased perspiration use Formidronum (Formidronum) — the liquid supporting 10 h formaldehyde, 50 h water, 39,5 h 95% of alcohol, 0,5 h cologne or Unguentum Formalini (Unguentum Forma-lini) made of boric acid (5 g), salicylic acid (2 g), formalin (15 g), glycerin (14 g), poly(ethylene oxide) (62,5 g), a fragrance (1,5 g). Ointment has white color and a slight smell F. and fragrances.

In the industry F. use as the source of formaldehyde convenient for transportation and storage.

Use of formalin in the histologic equipment and anatomy. T.

in pure form, and also with addition of a number of salts is a universal fixing agent. Besides, F. is a part of many complex fixing liquids: a tsenker-formola, alcohol -

a formol, liquids Horta, Rego, Ramón-and-Kakhalya, etc. Believe that the fixing properties F. are based first of all on its ability to connect to proteins and to denature them. Solutions F. usually prepare on mains water, edges partially neutralizes usual acid reaction F. For the majority of ways of coloring of fabrics acidity F. it is not harmful, and at nek-ry ways of a research of nervous tissue it is even desirable. However F. is less suitable for gistol. identifications of iron, a glycogen, for studying of fine structures of a cellular kernel, and also during the use of colourings with azur-eosine. During the use of formalin with pH lower than 6,0 in the fabrics especially rich with blood, the brown «formalin pigment» — acid formalin hematin appears. This pigment can be removed in the way obrabotkr1 material of 1% with solution of spirit of ammonia or caustic heat for 70% alcohol or 3% solution of hydrogen peroxide. For improvement of perception by fabrics of coloring, and also for the purpose of prevention of emergence of «a formalin pigment» solutions F. neutralize. For this purpose on a bottom of a large bottle with F. fill a layer of chalk or magnesia 2 — 3 cm thick and periodically shake up liquid. In a day the size pH increases to

6,3 — 6,5. Neutralization F. control by means of indicators — litmus papers or by addition to solution of 0,1% of solution of neutral red (emergence of orange-yellow coloring demonstrates achievement of the neutral sizes pH). Full fixing of pieces of fabrics up to 2 cm thick in 10% solution F. at the room temperature occurs for 1 — 2 days, in 2% solution F. at a temperature of 55 ° — during the 3rd hour. Than kontsentrirovanny solution F. the consolidation of the fixed fabrics is more considerable. Very concentrated solutions detain fixing, causing sharp consolidation of surface layers of pieces of the fixed fabrics. At full fixing the piece of fabric on a section has evenly gray-brown color due to recovery of oxyhemoglobin of blood in mt hemoglobin. Material in F. it can be stored for years. T. in pure form, and also in complex mixtures it is used for fixing and storage of the bodies and fabrics intended for production of anatomic drugs (see Drugs anatomic) and for embalming of corpses (see).

Formalin as professional harm. Main toxic effective agent F. formaldehyde — gas with a caustic suffocating smell is. Formaldehyde at its receiving and use is emitted in air of production rooms, is present at exhaust gases of cars and emissions of power plants at incomplete combustion of organic fuel. Formaldehyde can be emitted from various construction materials, fabrics and other products, by production to-rykh the polymers containing formaldehyde were used (see. Polymeric materials, Pitches with and N those t ichesk not).

Formaldehyde — the strong poison of irritant action striking c. N of page and causing dystrophic changes of parenchymatous bodies. In an organism formaldehyde is oxidized with formation of formic acid (see) and methyl alcohol (see). The threshold of irritant action of formaldehyde for the person is equal to 2,4 mg/m3.

At hron. poisoning with formaldehyde in low concentrations there are dispeptic disorders, disturbances of sweating, rhinitises, pharyngitises, emphysema of lungs, hron develop. bronchitis (it is frequent with an asthmatic component), hyperesthesias and hyperalgesias, defeat of c. N of page (hyperphrenia, headache, sleep disorder, visual disturbance, ataxy). In hard cases quite often note a diffusion toxic pneumosclerosis, damage of a liver (jaundice) and kidneys (oliguria), emergence of a small tortoiseshell, a rhinopathy, asthmatic bronchitis, allergic gastritis, a Quincke's edema, dermatitis and eczemas of the allergic nature, development of a pulmonary heart. Often nails are surprised (note their softening, fragility).

Treatment hron. intoxications formaldehyde symptomatic at the unconditional termination of contact with the irritating agent and temporary transfer for other work.

At acute inhalation poisoning with formaldehyde the phenomena of defeat of a conjunctiva (dacryagogue, gripes in eyes) and a mucous membrane of upper respiratory tracts prevail (irritation in a throat, cold, sneezing and cough, short wind, suffocation) up to a fluid lungs, toxic gepato-and a nephropathy, the general weakness, perspiration, headaches, shaky gait, face skin is hyperemic, sometimes there are dizziness, sensation of fear, spasms. After the postponed poisoning note sensitization to F.

At intake of poison inside — a wedge, a picture of a chemical burn of a digestive tract, vomiting with blood, thirst, toxic shock.

At hit on skin of solutions of formaldehyde (even divorced to 0,015%) the hyperemia and infiltration of skin, sometimes with formation of firm nodules and cracking of the hardened surfaces can develop.

And e r in and I am the help and N e-turn-down therapy. At - irritation of eyes in case of poisoning F. urgent washing by their warm water, 2% solution of hydro-sodium carbonate or isotonic solution of sodium of chloride, an instillation

of 2 — 3 drops of 1% of solution of novocaine or 0,5% of solution of Dicainum is shown. At hit of formaldehyde on skin it is necessary to wash immediately an affected area of 5% solution of spirit of ammonia or water.

At inhalation poisoning with formaldehyde it is necessary to take out urgently the victim on fresh air, to provide inhalation of water vapor (add several drops of spirit of ammonia to hot water); in hard cases — alkaline or oil inhalations. At fits of coughing — inside codeine, dionine. At a laryngospasm subcutaneously enter 0,5 — 1,0 ml of 0,5% of solution of atropine, in hard cases make an intubation (see) or a tracheostomy (see), actions for fight against a fluid lungs (see). At an acute heart failure warming of a body, hypodermic administration of camphor, caffeine, Corazolum or Cordiaminum (1 — 2 ml) is necessary. For stimulation of breath introduction of Cytitonum or lobeline is recommended. At hit of poison the immediate plentiful gastric lavage

of 2 — 3% solution of hydrosodium carbonate, drink of the mix consisting of 2% of solution of salts of ammonium from 10 — 20% of urea, the enveloping means (crude eggs, mucous broths) inside is necessary. Further treatment — symptomatic.

Examination of working capacity. At slight poisoning temporary transfer of the victim for other work is shown, at a serious poisoning, the expressed and resistant phenomena of intoxication transfer into work out of contact with formaldehyde and rational employment is necessary.

Measures of ii r about f and l and to t and to and. For working in contact with formaldehyde or T. use of individual protection equipment — the filtering industrial gas masks of brand A, the isolating hose gas masks (see), protective clothes is obligatory (see Clothes special). Preventive actions include sealing of the equipment, improvement of the equipment and a techno of l. processes, implementation on production of distance steering, installation of effective ventilation (see). Also periodic medical examinations (1 time in 12 months) all working in contact with formaldehyde are obligatory preliminary (see. Medical examination).

Maximum allowable concentration of formaldehyde in air of a working zone makes 0,5 mg,

м:\ Формалин в судебно-медицинском отношении. Poisonings at receipt F. inside have generally accidental character. During the opening of the dead from poisoning F. during the first hours after intake of large amounts of poison find a chemical burn of a mucous membrane of a mouth, gullet and stomach (due to the fixing action F. on erythrocytes of a prokrashivaniye of nekroti-zirovanny fabrics a blood pigment does not occur, and they have white or pink-gray coloring), consolidation, wrinkling of a wall of a stomach, and at longer course of poisoning — also expressed dystrophic changes of kidneys, a liver, a myocardium. Histologically find a necrosis of a mucous membrane, and sometimes and a muscular layer of a gullet and a stomach, swelled also infiltration of submucosal and muscular layers, in nek-ry cases — a phlegmonous inflammation of all wall of these bodies; nekronefroz, degenerative changes of neurons of a cerebral cortex, sharp plethora of vessels and perivascular hemorrhages in tissue of a brain.

At court. - chemical identifications F. it is isolated from biol. material wet distillation. High-quality detection F. in distillate it is based on reactions with the concentrated chamois to - that (at addition of codeine or morphine red or blue-violet coloring) or with the concentrated chamois to - that is formed and solution fuksinsernisty to - you (blue or blue-violet coloring appears; take the coloring developing no more than in 30 min. into account). Quantitative definition F. carry out the volume metric titration of iodine or a colorimetric method (see Colorimetry) based on interaction F. with fuksinsernisty to - that.

Bibliography: Harmful substances in the industry, under the editorship of N. V. Lazarev and E. N. Levina, t. 1, page 505, L., 1976;

Kissels D. Prakticheskaya of the microtechnician and a histochemistry, the lane with Wenger., page 54, Budapest, 1962; Lille R. Patogistologicheskaya of the technician and a practical histochemistry, the lane with English, page 36, etc., M., 1969; Merkulov G. A. Course of the patologogistologichesky equipment, page 13, etc., L., 1969; Acute management at acute poisonings, under the editorship of S. N. Golikov, page 284, M., 1977; Roberts J. and To and with e r and about M. Fundamentals of organic chemistry, the lane with English, t. 1 — 2, M., 1978; The Guide to forensic medical examination of poisonings, under the editorship of R. V. Berezhny, etc., page 78, M., 1980; The reference book on professional pathology, under red * L, N. Gratsianskoy and V. E. Kovshilo, page 4, L., 1981; Shvaykova M. D «Toxicological chemistry, page 83, M., 1975; Shrayner R., etc. Identification of organic compounds, the lane with English, M., 1983; Blum F. Der Formaldehyd ais antisepticum, Miinch. med. Wschr., S. 601 * 1893.

H. G. Ivanov (gigabyte.)

4 II. F. Kaliteevsky (gist.), H. Century of a 11ro-kazov (biochemical), A. F. Rubtsov (court.).