Cyanide compounds

Cyanide compounds combine a large class of substances (hydrogen cyanide, hydrogen cyanide metals, ditzian, one of diziana, esters lunarwing or ciampolini acid; NITRILES, isonitrile, some complex cyanide salts and other), the structure of which includes a group CN. The most typical connection among them is hydrocyanic acid - HCN (colorless easily movable liquid with a smell of bitter almonds).
Cyanide compounds are used in electroplating coverage metal copper, brass, gold and silver, are used for hardening and liquid cementation metals. In agriculture cyanides are used to control pests of fruit trees, grain. The main route of penetration of cyanide compounds in the body in the production conditions are respiratory organs, but they can come through the digestive tract, intact skin.
The toxic effect of cyanide compounds is in blockade, respiratory function of cells and tissues.
At short-term inhalation of HCN in the concentration of 0,005 - 0,02 mg/l - at the individual, individuals may experience dizziness; by prolonged exposure through inhalation concentration of 0,02-0,05 mg/l, headache, nausea, vomiting, palpitations. The concentration of 0.1 mg/l dangerous to life (death usually occurs within the first hour); 0,12 - 0,15 mg/l - death after 30 minutes - 1 hour; at 0.2 mg/l is death after 10 minutes; without serious consequences can withstand for 1 minute of concentration 0.55 mg/L.
Picture of acute poisoning in humans: when high concentrations of cyanide compounds almost instantly lost consciousness comes respiratory paralysis and heart. At lower concentrations, there are several stages. The initial stage, dizziness, feeling of pressure in the forehead, severe headache, shortness of breath, a rush of blood to the head, heart. Stage of apnea is a rare and deep breathing, slow heartbeat; nausea, vomiting, dilated pupils and other stage of convulsions, loss of consciousness, convulsions (often tetanicescie); twitching of chewing muscles with occlusion of the language. Stage paralysis, or asphyxia,is a complete loss of sensation and reflexes, involuntary urination and bowel movements, rare breath.
At the showdown: liquid blood plethora meninges, hemorrhage, a sharp increase in the permeability of the vascular wall. Blood and cadaveric spots bright red. In the brain degenerative changes of nerve cells; in the liver, kidney and heart - granular dystrophy.
There are several forms of chronic poisoning cyanide compounds (mainly HCN): cardio-pulmonary - with the phenomena of hypertrophy of the heart, lowering blood pressure and bronchoalveolar the stasis; blood - higher levels of hemoglobin and erythrocytes, monocytosis, and limfotsitoz; alimentary - increasing metabolic rate and blood sugar levels; nervous - with shortness of breath, dizziness, fatigue, convulsions, headache, insomnia, memory loss, and others; skin with local skin lesions.
General prevention is to ensure the integrity of devices and equipment.
Strict observance of personal hygiene: use of industrial filter gas mask mark "In" or gas mask BKF; at very high concentrations of cyanide compounds need insulating gas masks; compulsory skin protection.
MAC HCN and its salts (in terms of HCN) in the air of working premises 0.3 mg/m3.
First aid includes urgent removal of the exposed person to fresh air; in the first few minutes to give to breathe 5-8 drops amilnitrita, intravenous 10-15 ml of 2% solution of sodium nitrate or 50 ml of chromosome (1 % solution metilenovogo blue in 25% glucose solution). After 3 to 5 minutes intravenously 20-50 ml of 30% solution of sodium thiosulfate and simultaneously provide the patient with oxygen; peace; heat. If signs of poisoning resume - antidote (sodium nitrite, and then sodium thiosulfate) should to enter it again (after an hour) in the same doses. It is also recommended intravenous injection of 50 ml of 40% glucose solution with vitamins B1; B2, Niacin, ascorbic acids; with a weak pulse and low blood pressure - intravenous 40 ml of 1.5% solution diablitos salt ethylenediaminetetraacetic acid. Medical follow-up for victims of not less than 5-7 days.
Cm. the industrial Poisons.

Cyanide compounds - chemical compounds which structure includes the group CN. These include, in particular, include cyanide salts of hydrocyanic acid.
Cyanide compounds as industrial poisons. Cyanide compounds are used in electroplating coverage metal copper, brass, gold and silver, is used to extract gold and silver from ores, hardening and liquid cementation of metals, for cyanidation steel. In agriculture cyanides are used to control pests of fruit trees, grain, cotton, destruction, storage pests and ground squirrels (deratization). The greatest application in industry are: sodium cyanide (NaCN), cyanide (KCN) and cyanide, ammonia (NH3CN), which is in the air under the influence WITH2 and especially when heated easy decays with allocation of hydrocyanic acid.
The main route of penetration of cyanide compounds in the body in the production conditions are respiratory organs. Penetrate through the intact skin contributes to its redness and increased sweating. Cyanide compounds can get into the body through the digestive tract, where under the influence of hydrochloric acid is formed hydrogen cyanide.
Highlights of cyanide compounds (partly in an unmodified form) through the lungs. Decontamination of cyanide compounds in the body occurs mainly through merger of sulfur and their transformation into compounds that are excreted in the urine. In the process of neutralization of cyanides in the body take part and carbohydrates, forming harmless tangerine. Possible oxidation part of hydrocyanic acid in cyanide, which is then hydrolysed, broken down to carbon dioxide and ammonia.
The mechanism of action. When ingestion of cyanide compounds cause a blockage of the respiratory function of cells and tissues. Active connection hydrocyanic acid with oxidized form of helenfernanda (trivalent iron) prevents the oxidation of cytochrome. This creates an obstacle to the restoration of the iron respiratory enzyme in the ferrous form, and thus the transport of oxygen to the cytochrome. Thus, the toxic effect of cyanide compounds is manifested in inhibition, paralysis of the consumption of oxygen by cells. Respiratory function, which is provided iron free catalysts, remains intact. However, this "residual breath", carried out near the extension of the subsidiary catalysts, has low capacity and lack of efficiency. This defines the development impact of cyanide compounds main symptoms of anoxia gistologicescoe type: content and the partial pressure of oxygen in arterial blood is normal, and in venous blood sharply increased and almost no different from the blood. This form of oxygen deficiency usually accompanied by a reduction of CO2, which is largely due to a sharp oppression oxidizing processes. Sharp decrease of arteriovenous differences in the content of oxygen causes scarlet venous blood, bright pink color of the mucous membranes and skin intoxicated with cyanide.
When the acute toxicity of cyanide compounds distinguish the following stages: 1) primary phenomenon, 2) shortness of breath, or diplomaticheskaya stage 3) convulsively and 4) paralytic, or efektidega, stage.
In milder degrees of poisoning usually develop phenomena of the first stage of intoxication: a bitter taste in the mouth, burning sensation in the epigastric region and swelling of mucous membrane of the tongue and mouth, nausea, increased drowsiness, dizziness, muscle weakness, difficulty speaking, pain in the heart, shortness of breath, tachycardia. After the cessation of contact with the poison of these effects usually disappear quickly and without any consequences. In case of continuing contact with cyanide or when exposed to higher concentrations their develops diplomaticheskaya stage: disturbed consciousness, there stunned state and sudden muscle weakness, exacerbated pain in the heart, the heart rate slows down and becomes tense. Greatly disturbed breathing rhythm: it slows down and becomes deep.
With the further development of the process are observed loss of consciousness, uncoordinated movements, convulsions tehnicheskogo nature. In the most severe cases of poisoning cyanide compounds spasmodic muscles replaced them with relaxation, there comes a loss of sensitivity and reflexes. Often there are involuntary urination and defecation; pulse quickens, blood pressure falls, the breath becomes more rare and superficial, is paralysis of the respiratory center. The heart may still for a few minutes to decline after stopping of breathing.
The stages of development of clinical symptomatology of acute intoxication of cyanide compounds conditional, as in the case of slight intoxication usually reverse the development process. When exposed to high concentrations of poison rapid development of intoxication complicate the differentiation of the various stages. Described cases of fulminant death with the direct action of the large concentration of hydrocyanic acid. In production cut cases of poisoning cyanide compounds are very rare.
The correct diagnosis of acute intoxication of cyanide compounds contribute bright pink mucous membranes and the skin and the smell of bitter almonds mouth. The latter is an important differential diagnostic test, allowing to exclude acute intoxication carbon monoxide, which is also observed in the same bright-pink mucous membranes and skin. Acute poisoning nitrobenzene (Kurbanova oil), in which also there is the smell of bitter almonds mouth, may be excluded due to the characteristic gray-blue colouring of external covers in connection with the formation of methemoglobin.

Chronic poisoning different cyanide may develop with prolonged exposure to low concentrations of cyanide compounds (thousandths of 1 milligram per liter). Thus, there is a diverse, variable symptoms. Common complaints of General weakness, headache, dizziness, lack of appetite, nausea, ringing in the ears, the weakening of memory, palpitations, pain in the heart area. Objective research reveals change the function of the cardiovascular system: bradycardia, hypotension, deafness tones heart and phenomena angina. To the characteristic of objective symptoms of some authors include enlargement of the thyroid gland, increased sweating, hypersalivation.
From the hematological changes marked increase in the number of red blood cells and hemoglobin. There are indications of infringement of oxidative processes: a decrease in the content of glutathione and catalase in the blood (S. I. Ashbel and E. I. vellinge). When the impact of the solutions of potassium cyanide observed lesions: itching, persistent rash, subacute or chronic eczema.
Treatment. In cases of acute intoxication must victim infected atmosphere, free from contaminated clothing and create conditions of complete rest, to apply heat. One of the main ways of treatment of acute poisoning cyanide compounds is turning part of hemoglobin into methemoglobin, which, greedily connecting with cyanide compounds circulating in the blood, and taking it from tissues, helps to restore normal function of the respiratory catalysts. For this purpose apply inhalation amilnitrita (2 to 3 drops with cotton wool, gauze or handkerchief), atomistically sodium (5 to 10 ml 1-2% solution intravenously), methylene blue (50 ml of 1 % solution intravenously). Very effective intravenous injection of 50 ml antidote "chromosme" (1 % solution metilenovogo blue in 25% glucose solution).
To activate processes of detoxification and acceleration neutralization of cyanides, entering the bloodstream and were created by the splitting of the cyanmethaemoglobin, it is recommended intravenous injection of 20 ml to 30% solution of sodium thiosulfate (G. F. lang). Serves the same purpose, and intravenous drug glucose (20-30 ml of 40% solution), which contribute to the neutralization of cyanides by transformation into tangerine.
When oppression respiratory centre - Carbogen inhalation, lobeline (subcutaneously to 1 ml intravenously - 0.5 ml of 1% solution) or tsititon (0.5 - 1 ml intravenously). To restore the activity of the cardiovascular system applied camphor, caffeine, korazol, kordiamin. In the fall of cardiac activity is administered epinephrine solution 1 : 1000 and 1 ml subcutaneously or 1 ml of 5% solution of ephedrine. Recommended inhalation of oxygen to increase the number of free dissolved in the plasma of oxygen, which can promote a more energetic oxidation of hydrocyanic acid and its transfer in low-toxic cyanic acid.
The effectiveness of first aid in case of acute poisoning cyanide is determined in large measure speed and clear sequence of the execution of these activities.
In chronic intoxication - restorative treatment, physiotherapy; intravenous glucose, vitamins.
In the prevention of cyanide poisoning is especially important to ensure the integrity of the equipment and the equipment cyanide electroplating baths local mechanical ventilation, mechanization of production processes and separate operations (loading and unloading of workpieces at the cyanidation and others), warning of the possibility of falling into alkali cyanide baths acidic solutions to avoid rapid allocation of HCN and severe poisoning.
You must carefully ventilate the room after disinfection of cyanide compounds and produce control of air before entering them. Due to the high toxicity of cyanide requires the use of special devices and automatic alarm system for continuous monitoring of the air environment.
Necessary detailed briefing and introduction to working with properties of cyanide and their high toxicity. Obligatory observance of personal hygiene. Maximum permissible concentration of cyanide compounds in the air - 0.0003 mg/L.
Cm. the industrial Poisons.