Polymer Compound Poisoning

Polymers, also known as polymers or copolymers, are macromolecules with molecular weights of up to several thousand to several millions, resulting from the polymerisation or polycondensation of one or more monomers, due to the superior properties of many natural materials. Such as high strength, corrosion resistance, good insulation, light weight, etc., have been widely used in various fields of the national economy.

One, the main cause

The polymer compound itself is relatively stable under normal conditions and is basically non-toxic to the human body. However, some free monomers or additives may be released during processing or use, which may cause some harm to the human body. For example, the phenolic resin can be released during use. Phenol and formaldehyde, polyvinyl chloride can release lead compounds used as stabilizers.

Some of the polymer compounds can produce extremely toxic pyrolysis products when heated or oxidized, such as tetrafluoroethylene, hexafluoropropylene, and octafluoroisobutylene, which can be decomposed by heating PTFE to 420 °C . Very strong, can cause severe toxic pneumonia and pulmonary edema after inhalation. A large amount of CO can be generated when the polymer compound burns , and the surrounding environment is devoid of oxygen; some of the compounds can also generate the aforementioned thermal cracking products; and compounds containing nitrogen and halogen can generate hydrogen cyanide, phosgene, hydrogen halide, etc. Substances are particularly harmful to the body.

We will select some monomers, additives or pyrolysis products commonly used in the production of synthetic resins, synthetic fibers, and synthetic rubbers, such as vinyl chloride, polytetrafluoroethylene pyrolysis gas, dilin, acrylonitrile, chlorohydrin, neoprene. Dienes etc. are introduced as follows.

Second, toxic effects

1. vinyl chloride

At room temperature and pressure, it is a colorless gas with a slight fragrance. It is flammable and explosive. It is easily liquefied when pressurized. It can be decomposed by hydrogen chloride, CO2 , CO , phosgene, etc. when burned . It is slightly soluble in water and soluble in alcohol. , Easily soluble in ether, carbon tetrachloride, etc. It is mainly used in the manufacture of polyvinyl chloride monomer, to form a copolymer with vinyl acetate, acrylonitrile, vinylidene chloride, etc., and used as the insulating materials, adhesives, coatings, synthetic fibers and the like. VC mainly uses acetylene and hydrogen chloride as raw materials catalyzed by HgCl2 . In this process, vinyl chloride can be contacted, and in the process of polymerization into polyvinyl chloride, especially when the polymerization kettle is cleaned, it is easier to contact a large amount of VC .

VC enters the body mainly through the respiratory tract, and the skin is only slightly absorbed. Inhalation of VC in the body more exhaled in the original form, stop contact for 10 minutes, about 82 % can be discharged ; high concentrations of inhalation is mainly for anesthetic effects, and due to the inhalation of oxygen content in the relative decline in oxygen deficiency. People have dizziness, nausea and other symptoms at a concentration of 30g /m3 ; anesthesia concentration is about 182g /m3 .

2. Polytetrafluoroethylene (PTFE) pyrolysis gas

PTFE is a homopolymer of tetrafluoroethylene (TFE) . It has stable chemical properties, excellent resistance to electrical discharge, heat resistance, and corrosion resistance. It is called "Plastic King" and it is non-toxic. The pyrolysate is toxic. The toxicity is directly related to the temperature: The thermal lysate at > 315 °C only has respiratory tract irritant effects; the product at > 400 °C has a strong stimulatory effect on the lungs due to hydrolyzable fluoride ( hydrogen fluoride fluorine phosgene) generated; or higher 500 ℃, can be detected tetrafluoroethylene, hexafluoropropylene, octafluorocyclobutane, and a large number of octafluoroisobutene, fluoro phosgene, more toxic.

It is generally believed that the toxicity of PTFE pyrolysis gas is mainly caused by octafluoroisobutylene, phosgene, and hydrogen fluoride. Its main role is the strong stimulation of the lung, can cause pulmonary edema, pulmonary hemorrhage, pulmonary fibrosis; myocardium can also appear edema, degeneration, necrosis; In addition, the liver, kidney and central nervous system also have poisoning damage occurred.

3. Diner

Also known as dowthem A , it is a mixture of biphenyl (26.5 % ) and diphenyl ether (73.5 % ) and is mainly used as a heat carrier in the production of polymer compounds. It is a slightly yellow odorous liquid with a boiling point of 258 °C and heated to 400 °C without decomposition. It is insoluble in water and soluble in alcohol, ether and benzene. This product has strong stimulation to the skin, mucous membrane and respiratory tract. It also has damage to the central nervous system and can cause toxic encephalopathy.

4. acrylonitrile

It is colorless, flammable, explosive, volatile gas, with almond odor, slightly soluble in water, easily soluble in organic solvents; unstable aqueous solution, easily hydrolyzed to acrylic acid under alkaline conditions, and generated propionitrile when reduced. AN can be polymerized into polyacrylonitrile, and can also be copolymerized with itaconic acid, butadiene, vinyl acetate, styrene, vinyl chloride, etc., for the manufacture of synthetic fibers, synthetic rubber, synthetic resins, and the like.

AN enters the body through the respiratory tract, skin, and digestive tract. AN into the body over 1 hour only a small amount (about 5%) to the prototype exhalation, with about 10% excreted unchanged in urine, and another 15% is discharged in the form of thiocyanate. In the case of acute poisoning, AN may play a major role in the precipitation of cyanide; in addition, the AN molecules that have not been excreted and dissociated have their own damage to the central nervous system.

5.2 -Chloroethanol

This product is obtained by hydrolysis of ethanol and chlorination. It is mainly used for the production of ethylene glycol in the production of synthetic terylene. It is a colorless, transparent liquid with an ether-like odor and is volatile; soluble in water and various organic solvents. This product has damage to the central nervous system and lung, liver, kidney and other important organs may be caused by the role of the product in the liver through the role of Coenzyme I, converted to chloroacetaldehyde.

6. Chloroprene

Under the normal state, it is a colorless liquid with pungent odor. It is volatile, slightly soluble in water, and easily soluble in various organic solvents. This product is easily oxidized in the air. It can polymerize quickly under the action of light and catalyst. It can explode in the presence of fire or hot metal to generate phosgene and various chlorides. It is mainly used for the production of neoprene and other polychloroprene products.

In industrial production, chloroprene is mainly absorbed into the body through the respiratory tract and skin, only a small amount is excreted through exhalation and urine as prototypes, chloroprene that enters the body is mainly distributed in lipid-rich tissues; it is not only irritating , Can cause eye, skin, respiratory and lung injury, also has significant damage to the central nervous system, liver, kidney and other tissues, the study believes it may be related to its conversion to acid or epoxide in the body, the latter has a strong activity Can cause lipid peroxidation, so chloroprene poisoning animal or human body, blood or tissue reduced glutathione (GSH) , and lipid peroxidation product malondialdehyde (MDA) increased.

Third, the clinical manifestations

1. Acute vinyl chloride poisoning

More common in cleaning polymerizers, repair equipment, or accidental inhalation of large amounts of vinyl chloride vapor. Mainly manifested as dizziness, headache, euphoria, nausea, chest tightness, fatigue, drowsiness, gait, etc., such as timely disengagement, more quickly recover; if you continue to inhale, or inhalation concentration is extremely high, you can quickly lose consciousness, Can die due to respiratory cycle inhibition. Skin contact with vinyl chloride fluid can cause local numbness, erythema, edema, and even necrosis. The presence of large amounts of vinyl chloride in the blood is important for diagnosis.

2. Teflon pyrolysis gas poisoning

Mainly due to inhalation of this gas caused by eye and respiratory irritation symptoms, and chest tightness, dry cough, etc.; severe cases are palpitations, chest pain, purpura, both lungs covered with dry and wet rales even alveolar pulmonary edema, this time Visible shortness of breath, purpura obvious, irritability, slightly frothy sputum, combined with myocardial damage, visible arrhythmia, conduction block and ST segment, T wave abnormalities and other performance; liver and kidney function indicators may also be abnormal. Chest X -ray examination can be seen early in the increase of thickening of the lung texture, blurred edges or reticular formation of the lung field; performance of pulmonary edema, there are still visible hilar enlargement, the size of the lungs covered with patchy shadows Such performance. The incubation period for pulmonary edema is from a few hours to 24 hours.

There are some PTFE suction gas thermal cracking may occur "polymer fume fever", fever and flu-like symptoms, generally 1 to 10 hours after the inhalation occurs, no chills, body temperature and more at 37.5 ~ 39.5 ℃, sustained About 4 to 12 hours, often accompanied by white blood cell count and increased neutrophils; 1 to 2 days can be self-healing.

3. Daniel's acute poisoning

More common in repairing equipment or accidental inhalation of a large amount of vapor caused by, in addition to eye and respiratory tract irritation, there are headaches, dizziness, dizziness, fatigue, nausea, vomiting, drowsiness, and even loss of consciousness, due to odor, there will be no more A long period of high inhalation occurs.

4. Acute acrylonitrile poisoning

High concentrations of inhalation or skin contamination are the main causes of occupational acute poisoning. Except for irritation of the eyes and upper respiratory tract ( skin contamination may cause local erythema, papules, or blisters ) , the main manifestations are headache, dizziness, fatigue, nausea, and vomiting. , Chest tightness, numbness of hands and feet, purpura, consciousness disorder, severe cases can occur coma, convulsions, and even respiratory and circulatory failure, death. Acrylonitrile and cetylhemoglobin were detected in blood, and urinary thiocyanate was significantly increased, which has important implications for diagnosis.

5. 2 -chloroethanol acute poisoning

Industrial production is mainly caused by inhalation of its high concentration of vapors or large areas of skin contamination, which is much milder. The main symptoms are headache, dizziness, chest tightness, stasis, nausea, and vomiting; at high concentrations, symptoms of excitatory mania can occur within a few hours, and coma, respiratory and circulatory failure, and death can occur quickly; obvious brain edema and pulmonary edema can be seen at autopsy. And liver and kidney damage.

6. Acute chloroprene poisoning

It is rare in clinical practice. Occasionally, accidental or illegal repair occurs, which is mainly caused by inhalation of high concentrations of vapors. Mainly manifested as tearing, coughing, dizziness, headache, nausea, chest tightness, shortness of breath, severe cases can occur breathing difficulties, dry and wet rales in the lungs, tremors, cramps, cold extremities, consciousness disorders or even coma, death; detailed examination is still Visible liver and kidney damage performance.

Fourth, treatment

1. Operation of group poisoning hospital treatment

2. Handling principles

The above-mentioned compounds are substantially free of special antidotal drugs. Although acrylonitrile poisoning can use detoxification drugs, it can only reduce some of its toxicity. Therefore, symptomatic and supportive therapy, especially the active prevention and treatment of damage to important organs, is the focus of such poisoning treatment.

3. Specific measures

(1) In addition to the general principles of vinyl chloride poisoning promptly separated from toxic exposure, contaminated clothing, and contaminated skin, oxygen and respiratory stimulants may be given; those who have respiratory and circulatory arrest should immediately undergo cardiopulmonary resuscitation; Give nonspecific detoxification and supportive treatment.

(2) The respiratory system performance of PTFE pyrolysis gas poisoning can be treated by acute irritant gas poisoning, especially attention should be paid to the early enough application of glucocorticoids, and electrocardiogram and liver and kidney function monitoring must be strictly performed. Early use of inosine, energy mixture, GIK solution, calcium channel blocker, oxygen free radical scavenger, attention to make up the blood volume, appropriate use of dehydrated diuretics, once the heart, liver, kidney and other damage performance, re-cast Use symptomatic and nutritional support medications.

(3) Daniel Poisoning focuses on the treatment of toxic encephalopathy. Patients should be given oxygen and enough glucocorticoids should be given as soon as possible. Diuretic dehydration can be performed early, calcium channel blockers, oxygen free radical scavenger can be used, __ energetics, and pay attention to body fluid balance.

(4) Acrylonitrile poisoning Inhalation poisoning should be immediately rescued from the scene; skin polluters should remove contaminated clothing, wash skin with 5 % sodium thiosulfate or soap, water; oral can be used 2.5 % sodium thiosulfate or water Saline was fully lavaged with saline, and then it was drained with sodium sulfate (20 g) , and 30 g of activated carbon was poured from the stomach tube to adsorb the remaining acrylonitrile. Patients can be given antidotes and give oxygen and respiratory stimulants; active prevention and treatment of brain edema, and strict monitoring of electrocardiogram, liver and kidney function, early application of anti-drug drugs.

(5) Patients with 2- chlorohydrin poisoning should be given enough glucocorticoids (oxygen-radical scavengers ) at an early enough dose ( > 60 mg/day) to be given oxygen; early diuretic dehydration and the use of energy mixture, calcium channel blockers, and oxygen free radical scavengers Early treatment of anti-pulmonary edema ( see irritant gas poisoning section ) ; early monitoring of electrocardiogram and liver and kidney function, and the use of heart and liver and other nutritional support drugs, such as inosine, vitamin C , GIK solution, liver tylo, glucose Etc., if there is damage, it should be actively dealt with. Patients with excitatory ecstasy can be treated with diazepam or artificial hypothermia; diuretic dehydration therapy should prevent hypovolemic shock; circulatory dysfunction or coma can be used early naloxone.

(6) Patients with chloroprene poisoning should receive oxygen and early administration of glucocorticoids, naloxone, and early administration of oxygen free radical scavenger such as reduced glutathione, selenide, vitamin C, and E ; At the same time can be used energy mixture, mannitol or low-molecular dextran, attention to humoral balance; close monitoring of liver and kidney function, caution with liver and nephrotoxic drugs, early use of liver protection drugs, and maintain adequate blood volume, appropriate Diuresis; Resuscitation can occur immediately when respiratory and circulatory failure occurs.

The information in this article comes from the Internet and was reorganized and edited by China Rescue Equipment Network.