Organic solvents mainly refer to those liquids that can dissolve some organic substances that are insoluble in water ( such as oils, resins, waxes, hydrocarbons, dyes, etc. ) , and are themselves organic compounds. They exist in the liquid state at normal temperature and pressure; In the medium, it has no change in nature with solute.
I. Organic solvent types
There are many kinds of these compounds, many of which have the above properties and can be classified as organic solvents. Nearly 500 species are currently widely used in industrial and agricultural production, medicine, and scientific research . The most important of the approximately 100 species are roughly classified into ten categories according to their chemical structures .
(1) Aromatic benzene, toluene, xylene, ethylbenzene, styrene, etc.
(2) Fatty hydrocarbons such as pentane, hexane, gasoline and various petroleum products.
(3) Alicyclic hydrocarbons cyclopentane, cyclohexane, cyclohexene, decalin, turpentine, and the like.
(4) Halogenated hydrocarbons Chlorobenzene, dichlorobenzene, methylene chloride, chloroform, carbon tetrachloride, dichloroethane, trichloroethane, tetrachloroethane, dibromoethane, dichloroethylene, trichlorin Ethylene, tetrachloroethylene, etc.
(5) Alcohols Methanol, ethanol, propanol, butanol, benzyl alcohol, chloroethanol, cyclohexanol, decyl alcohol, and the like.
(6) ethers ether, diethyl ether, diisopropyl ether, dichloroethyl ether, 1,2-propylene oxide, epichlorohydrin, dioxane, tetrahydrofuran and the like.
(7) Ester esters, acetate esters, tri-o-cresyl phosphate (TOCP) , oxalates , carbonates, phosphonates, and the like.
(8) Ketone acetone, methyl ethyl ketone, pentanone, methyl n-acetone, methyl butanone, diacetone alcohol, acetonyl acetone, trimethyl cyclohexenone, cyclohexanone, methyl cyclohexanone, and the like.
(9) Diols Ethylene glycol, propylene glycol, dioxane, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, and the like.
(10) Others such as carbon disulfide, pyridine, acetonitrile, nitropropane, furfural, dimethylformamide and the like. Organic solvents are mostly used as reaction media for industrial production and chemical experiments, followed by fuels for internal combustion engines, paint raw materials and thinners, ink thinners, and cleaners; other pharmaceutical raw materials or raw materials for additives, extractants, degreasers, and other additives. Wax, preservatives, insecticides, adhesives, lubricants, antifreeze, coolants, etc.
Second, toxic effects
Due to the wide variety of organic solvents and their different chemical structures, the physical and chemical properties vary greatly. From the perspective of hygiene, the following commonalities can be summed up:
1 It is liquid under normal temperature and pressure, has strong volatility, and has its own unique odor and certain irritation;
2 Most of them ( except esters, some halocarbons ) have flammability and explosiveness;
3 excellent fat-soluble, can be absorbed through the skin, easily through the blood-brain barrier. The above common properties also determine that organic solvents have two common toxicities.
Organic solvents have different degrees of skin and mucous membrane irritation, skin contact can appear cleft palate, dermatitis or even burns; its vapor inhalation can cause cough, runny nose, severe cases such as esters, ketones, halogenated hydrocarbons can cause bronchitis Pneumonia, pulmonary edema, and even pulmonary hemorrhage.
2. Anesthetic effect
This is the most prominent common toxicity of organic solvents. Inhalation concentration is not high or the initial period of high concentration of inhalation, patients may have headaches, dizziness, blurred vision, excitement, nausea and other symptoms, continued inhalation can cause mental disorders, madness, Convulsions, convulsions, and coma can often be caused by heart rhythm disturbances, fibrillation, or respiratory arrest. As the anesthetic symptoms appear very quickly, the recovery from contact with organic solvents is also rapid, suggesting that the symptoms are caused by the direct action of organic solvents, rather than the secondary damage of its metabolites. The specific mechanism may be related to the high fat-solubility of organic solvents, which causes them to accumulate in a large amount in the phospholipids of nerve cells and fibers, and interfere with the generation and transmission of nerve impulses. It is also believed that certain organic solvents can still interfere with the biological oxidation of nerve cells. Process, and this kind of interference is reversible.
However, in addition to the above common toxicity, different organic solvents still have their special toxicity, such as some very strong neurotoxicity, can cause toxic encephalopathy, toxic neuropathy, and even lead to mental disorders; some can cause toxic liver disease, in Toxic nephropathy, toxic cardiomyopathy, etc.; chronic exposure, some can still cause aplastic anemia ( benzene, etc. ) , cancer ( polychlorinated biphenyls, carbon tetrachloride, etc. ) , teratogenic mutations ( carbon disulfide, etc. ), etc. .
Third, the clinical manifestations
The following is a typical organic solvent, toluene poisoning, based on the introduction of some of the poisoning performance of a relatively unique organ toxicity or more common organic solvents.
It is mainly produced from coal tar fractionation or petroleum cracking. It is the most commonly used diluent and solvent, and it is also a raw material for preparation of other chemicals such as TNT , benzoic acid, TDI , and dyes. Skin contact can cause chapped and dermatitis; splashing into eyes can cause redness, pain, and tearing. Vapor inhalation can cause dizziness, weakness, nausea, gait instability, numbness of the limbs, severe disturbance of consciousness, coma, convulsions, and conjunctival hyperemia, tearing, runny nose, coughing, and other mucous membrane irritation, and may even cause chemical Pneumonia; high concentration of inhalation can often induce arrhythmia, conduction block, ventricular fibrillation, and even cardiac arrest. Exhaled air and blood measured toluene, urine hippuric acid increased, an important role in the diagnosis.
2. Carbon disulfide
It is made by reacting sulfur vapour with hot charcoal. It can also be obtained from the fractionation of coal tar. It is mainly used for the manufacture of viscose fiber, cellophane, solvent, extractant, degreasing agent, insecticide, rubber vulcanization accelerator. Or prepare carbon tetrachloride and so on.
Skin contamination can cause irritation, numbness, and even dermatitis; eye splatter can cause congestion, tearing, photophobia, and pain. Inhalation of CS2 vapor can cause headaches, dizziness, fatigue, nausea, vomiting, numbness in the extremities, unstable standing, gait, blurred vision, euphoria, laughter, and drunkenness, such as drunkenness, and eye and respiratory irritation. Symptoms; Inhalation at higher concentrations ( > 1000 mg/m3) can cause extreme excitement, with severe psychiatric symptoms such as mania, hallucinations, extreme anger, and suicidal tendencies that can lead to loss of consciousness, convulsions or convulsions, coma, and hypothermia. Respiratory failure and death. Of the mental disorder, CS2 is very acute poisoning with manifestations characteristic; exhaled gas measurement and blood CS2, CS2 urinary metabolites (e.g. TTCA - 2- thioxo-thiazolidine-4-carboxylic acid) assay The exhaled air and the rotten radish taste of the contaminated clothes are all helpful for the diagnosis.
At present, the main uses of chemical synthesis of raw materials ( such as the production of vinyl chloride monomer ) , solvents, adhesives, also used as textile, petroleum, electronics industry degreasing agent and metal parts cleaner, caffeine extractant, gasoline explosion-proof agent.
Symptoms of acute inhalation are similar to those of toluene, but respiratory tract irritation is severe. In severe cases, coma, convulsions, and death may occur. Anatomical findings may indicate the presence of pulmonary edema; patients with deferred conditions may experience liver and kidney damage after 24 to 48 hours. Oral abuse is even worse. However, in recent years, it has been found that continuous overtime work ( more than 12 hours per day for more than 1 to 2 consecutive weeks ) can cause subacute poisoning. Its clinical features are characterized by toxic encephalopathy. The patient can quickly become unconscious and have obvious symptoms of increased intracranial pressure. , And the condition is often repeated, the mortality rate is high.
4. Carbon tetrachloride
It is generally produced by the catalysis of iodine in dry chlorine gas into CS2 . It is mainly used in the manufacture of dichlorodifluoromethane and chloroform, as well as industrial solvents, cleaning agents, degreasing agents, spice extractants, and Extinguishing agents, analytical reagents, etc.
Inhalation of high concentrations of CCl4 can cause rapid coma, convulsions, ventricular fibrillation, respiratory center numbness, and death due to its strong anesthetic effect. Patients with more severe disease course, in addition to anesthetic symptoms, there are eye and respiratory tract irritation and even pulmonary edema; 1 to 2 days after the occurrence of toxic liver and kidney damage performance, severe acute liver and kidney failure can occur, often this The important cause of death of type patients; few patients can still complicated peripheral neuropathy, retrobulbar optic neuritis, adrenal cortical hemorrhage. Oral 30 ~ 50ml can cause severe lethal poisoning, especially in liver damage.
Gasoline mainly C4 ~ C12 aliphatic hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons and sulfides containing a small amount, mainly used as diesel fuel, partially as a solvent or cleaning agent.
Inhalation of the vapor can cause anesthesia, eye and respiratory irritation; high concentrations of gasoline vapor inhalation can quickly cause disturbance of consciousness, convulsions, convulsions, coma, and brain edema. Chemical pneumonitis or pulmonary edema can also be seen. Some patients can also appear mentally. Symptoms such as panic, hallucinations, laughter, laughter, rickets and other attacks. Oral can cause chemical gastroenteritis, respiratory tract inflammation, nausea, vomiting, abdominal pain, diarrhea, bloody stools, cough, chest pain embolism, and combined liver and kidney damage. Gasoline accidental inhalation of the lungs, can cause chemical bronchitis, pneumonia, pulmonary edema, pulmonary hemorrhage, exudative pleurisy, severe cough, chest pain, bloody sputum, shortness of breath, cyanosis, chills, high fever; X- ray examination can be seen in patients with lung the shadow point sheet wettability, right lower lung common; individual patients even pulmonary hemorrhage - nephritic syndrome, the prognosis is poor.
Methanol is the most commonly used industrial solvent. Severe acute poisoning can be caused by inhalation of high concentrations of vapors or by ingestion of liquids. At the beginning, it is mainly a typical drunk-like phenomenon. After a latency period of 12 to 18 hours, it will appear after a large amount of methanol is converted to formic acid. Specific performance, mainly:
1 Toxic encephalopathy manifestations, such as severe headache, dizziness, nausea, vomiting, spasms, psychiatric symptoms, convulsions, coma, etc.;
2 acidosis symptoms, such as rapid breathing, pulse acceleration, fatigue, weakness, severe Kussmaul respiration, blood pressure drop; test can see CO2CP â†“, PaCO2 â†“, HCO3 â†“, BE â†“, blood pH â†“, potassium and anion gap (AG ) etc.
3 optic nerve damage performance, such as blurred vision, photophobia, eye pain, followed by flash, black eyes, diplopia, vision loss, dilated pupils, weakened light reflex, peripheral vision reduction; fundus examination visible optic disc Congestion, retinal edema, severe optic nerve atrophy, blindness;
4 other manifestations: Some patients may be associated with acute pancreatitis, and even heart, liver, kidney damage and peripheral neuropathy. Inhaled poisoning is rare in those with optic nerve damage, but regardless of the route, high dose intake can quickly cause coma, respiratory heartbeat and death; oral 30 ~ 60ml methanol can be fatal, about 15ml can cause blindness. Timely determination of blood concentrations of methanol and formic acid contributes to accurate diagnosis and judgment condition.
1. Handling principles
The principle of the treatment of acute poisoning of organic solvents, especially the operation of group poisoning hospitals, can refer to the irritating gas poisoning section. Due to the strong anesthetic effect of organic solvents, special attention should be paid to the timely application of cardiopulmonary cerebral resuscitation measures in the treatment process.
2. Pathogen treatment
(1) Specific detoxification treatment Most organic solvents do not have specific antidotes. When methanol is only poisoned, alcohol can be used to compete with alcohol dehydrogenase to prevent methanol metabolism and reduce the formation of toxic metabolites such as formaldehyde and formate. When the intake of methanol is small, you can take about 50 % ethanol, 2 ~ 3ml/kg ; oral dose is greater, you can according to 10ml/kg dose, with 1 ~ 5ml/kg/h , intravenous infusion of ethanol, Keep the blood ethanol concentration above 22mmol/L (100mg/dl) until the blood methanol concentration reaches
6mmol/L (20mg/dl) or less.
(2) Non-specific detoxification treatment can be applied to a variety of drugs or measures that can strengthen the body's metabolism, excretion, elimination or detoxification, such as oxygen, infusion of glucose and vitamin C , glutathione, glucuronic acid and so on.
(3) Diuresis is beneficial to enhance toxic discharge, but attention should be paid to the balance of liquid intake and output to prevent hypovolaemia shock.
(4) blood purification therapy Hemodialysis helps a lot of organic solvents, such as alcohols, halogenated hydrocarbons, but lower water-soluble organic solvents, blood perfusion of the adsorption and detoxification effect seems to be stronger.
3. Symptomatic support treatment
(1) The glucocorticoid should be put into use as soon as possible. If the condition is slightly heavier, it should be given 60 to 80 mg dexamethasone per day for 3 to 5 days.
(2) Early intervention with cell interventions such as oxygen free radical scavengers and calcium channel blockers ( see section on detoxification and special treatment ) .
(3) The chemical structure of naloxone is similar to many anesthetic agents. It is an extremely effective anesthetic antagonist and also suitable for organic solvent poisoning. It is very beneficial to the maintenance of circulatory function in poisoning situations.
(4) Pay attention to the maintenance of respiratory function central respiratory failure as a common symptom of organic solvent poisoning, should pay attention to the timely application of respiratory stimulants, such as Hui Su Ling (8mg intramuscularly, then 8 ~ 16mg added to the 250ml liquid intravenous drip to maintain ) Kalamin (0.25 to 0.5g) Subcutaneous or intramuscular injection, if necessary, can be repeated 1 to 2 hours ) , Lobeline (5 ~ 10mg intramuscular or 3mg intravenous injection, if necessary, 0.5 hours can be repeated once ), etc., those with poor results can be maintained by a ventilator.
(5) Organic solvent poisoning with severe circulatory system function can often lead to arrhythmia or even cardiac arrest. Immediate treatment is needed. For example, adiponectin can be treated with sitadiram (0.4 to 0.8 mg intravenously ) and propranolol (0.5 to 1.0 mg). Intravenous injection ) or verapamil (5mg intravenous injection ) and other control; ventricular fibrillation can immediately apply non-synchronous DC defibrillation; cardiac arrest should be immediate cardiopulmonary cerebral resuscitation ( see the rescue of critically ill patients ) . It should be noted that when many organic solvents are poisoned, the myocardium is highly sensitive to catecholamine drugs. Unless cardiac arrest is used, adrenal drugs should be used with caution to avoid ventricular fibrillation, but naloxone can be administered.
(6) prevention and treatment of toxic brain edema can be seen in the prevention of cerebral edema caused by asphyxiating gas poisoning; obvious restlessness, convulsions can be applied to stability, barbiturates or artificial hibernation therapy, in order to facilitate the body recovery.
(7) The prevention and treatment of toxic liver damage should be closely monitored liver function indicators, banned drugs with hepatotoxicity, as soon as possible to use liver protection drugs, intravenous injection of GIK mixed solution.
(8) The prevention and treatment of toxic kidney damage should avoid the use of drugs with strong renal toxicity, monitoring fluid intake and output, urine sediment and related renal function indicators, and early diuretic fluid replacement, if necessary, blood purification therapy.
This article is edited and compiled by China Rescue Equipment Network. Please indicate the link.
Nylon rope is a series of fiber diameters made of nylon chips. Nylon rope has excellent corrosion resistance, UV resistance, mildew resistance and chemical resistance.
Nylon rope has soft and smooth appearance, high strength, low elongation and convenient operation. It is one of the strongest synthetic fibers, with excellent elasticity and excellent wear resistance, so it is often used as Climbing Rope, safety rope, traction rope, industrial Hoisting rope, etc.
Double Braided Nylon Rope,Nylon Rope,Nylon Rope 4Mm,Nylon Braided Rope
Baoying Yiliyuan Rope And Net Co.,Ltd , https://www.ylyropes.com