Is epoxy resin toxic after curing? Epoxy resin. Treatment for intoxication and prevention

Epoxy resins contain epichlorohydrin and toluene, which at temperatures of 60 0C and above are released into the work area and negatively affect human health, affecting the nervous system and liver. Epoxy resins can also cause skin diseases (dermatitis, eczema) both through direct contact with them and when exposed to low concentrations of vapors from these products. The maximum permissible concentration for epichlorohydrin is 1 mg/m3.

ABOUT Epoxy resin hardeners are also toxic substances. Failure to comply with safety rules when working with them can lead to changes in the blood composition of workers, a decrease in blood pressure, and depression of the central nervous system. nervous system, breathing problems and other disorders in the body.

Hexamethylenediamine is a highly toxic product: at a vapor concentration of 0.1-0.01 mg/l, it causes a change in the composition of the blood and a decrease in blood pressure; If it gets in the eyes, it causes serious illness.

Diameter X (3,3"-dichloro-4,4"-diaminodiphenylmethane) is toxic. The maximum permissible concentration in the air of working premises is 0.7 mg/m3. This diamine exhibits carcinogenic properties. It has a harmful effect on mucous membranes, skin, respiratory organs and is a flammable product. Protective measures: respirator, rubber gloves.

N-Phenylenediamine has a harmful effect on mucous membranes, skin and respiratory organs, is a sensitizer, and weakly accumulates. In acute poisoning, lethargy, weakened response to irritation, severe shortness of breath, and paralysis occur. When working with it, you should wear safety glasses, rubber gloves, and respirators.

P polyethylenepolyamine in large doses leads to respiratory failure and depression of the central nervous system; with prolonged exposure to the skin, it can cause lesions such as ulcerative dermatitis. Contact of polyethylene polyamine in the eyes causes prolonged conjunctivitis. Bottom residues from the production of hexamethylenediamine and complex amines are significantly less toxic.
Anhydride vapors cause irritation of the mucous membrane of the respiratory tract and eyes, suffocation, and wheezing in the lungs.

Phenol-formaldehyde resins are toxic mainly due to the content of free phenol and formaldehyde, which cause diseases of the respiratory system, nervous system and dermatitis. Modified phenol-formaldehyde adhesives (phenol rubber, phenol polyvinyl acetal, etc.) are much less toxic.

Polyurethane adhesives are toxic due to the presence of isocyanates in their composition, the most toxic of which is toluene diisocyanate (TDI). It belongs to highly dangerous substances (hazard class 1), causes acute and chronic poisoning, and disruption of metabolic processes in the body. Isocyanates may cause headache, increased irritability, stabbing pain in the heart area.

When inhaled, they cause irritation of the mucous membranes of the upper respiratory tract, and in severe cases, asthma-like diseases with further chronic damage to the lungs. TDI has a cauterizing and irritating effect on the skin and disrupts some metabolic processes. In the air of the working area, the maximum permissible concentration of TDI should be no more than 0.05 mg/m3. If you are injured by toluene diisocyanate vapors, you must immediately remove the victim from the contaminated area. Isocyanates are removed from the skin with a cotton swab moistened with acetone or ethyl acetate, after which you should wash your hands warm water with soap.

Cyanoacrylate adhesives cause irritation of the mucous membrane of the nose and eyes, and if it comes into contact with the skin, an unpleasant burning sensation. Safety glasses and gloves should be used when working with these adhesives.

Adhesives based on acrylic acid derivatives are slightly toxic. They are not explosive, self-igniting or volatile substances. If acrylic adhesives come into contact with the skin of your hands, remove them with a cotton swab soaked in ethyl or isopropyl alcohol and wash your hands with soap and water.

Anaerobic compounds are low-toxic and belong to class 4 of low-hazard compounds (GOST 12.1.007-76). They do not cause acute inhalation poisoning even when exposed to saturated concentrations at 22-24 0C. Do not have a pronounced cumulative effect and do not cause local irritation skin However, repeated contact may result in dermatitis. To protect the skin, work should be carried out in protective gloves and a cotton robe with the supply and exhaust ventilation turned on.

Rubbers used in the production of rubber adhesives and for modifying a number of adhesives are non-volatile under storage and processing conditions and do not have a harmful effect on the human body. Some rubbers may be mildly irritating to the skin and have a slight sensitizing effect and direct contact with the skin should be avoided. If liquid rubber gets on the surface of the skin, it is recommended to wash it off with warm water (up to -50 0C). cleaning solution, containing 10% OP-7 or OP-10, 6% trialon paste, 1% sodium carbonate and 83% water. The toxicity of rubber adhesives is mainly due to the solvents they contain.

The toxicity of phosphate adhesives is determined by the presence in their composition phosphoric acid, therefore, when working with them, the same precautions should be taken as when working with acids.

Substances whose toxicity must be taken into account when working with adhesives include flame retardants - zinc borate, chlorinated paraffins and antimony trioxide. The toxicity of zinc borate is due to the presence of zinc oxide, which can cause an occupational disease - zinc fever, as well as boric anhydride, which has an irritating effect on damaged skin and mucous membranes. MPC of zinc oxide work area production premises 6 mg/m3, boric anhydride 5 mg/m3. When working with zinc borate, it is necessary to use personal respiratory protection and monitor constant work ventilation units, observe personal hygiene rules, take a shower after finishing work.

Chlorinated paraffins are low-flammable, non-toxic substances. However, due to the presence of CC14 in some of them (up to 2%), when processing them at elevated temperatures (200 0C), respiratory protection measures must be observed.

Antimony trioxide (Sb2O3) is a toxic substance. The fog formed by Sb2O3 vapor and its suspended dust remain stable in the air. If it enters the stomach, it causes a metallic taste in the mouth, salivation, nausea, vomiting, and stomach pain. Allergic skin diseases are possible. MPC (in terms of Sb) 1 mg/m3. Personal protective equipment - respirators, safety glasses, mittens or gloves made of thick fabric.

Some adhesives contain fillers, such as asbestos, boron nitride, aluminum powder, silicon carbide, etc. With prolonged contact with them, acute and chronic inflammatory diseases of the upper respiratory tract, chronic bronchitis and other diseases are possible.

A compound obtained by synthesis is a synthetic substance with a complex chemical structure. The term “” (ES) is more often used. It has been used in industry since the fifties of the last century. Its unique properties - chemical and mechanical resistance, durability, low shrinkage, improved adhesion, etc. - have ensured the widespread use of the polymer in various industries.

The main distinguishing feature is the preparatory stage. ES is not available in finished form. First it must be combined with a hardener. The contact of these two components initiates a polymerization reaction, which results in the formation of the finished product. The resulting liquid substance gradually hardens (on average 24 hours), forming a very strong adhesive layer, or a product of the required parameters, or a durable protective coating.

There are two types: hot and cold curing. In production, a “hot” variety is used, the so-called “technical”, characterized by increased operational properties. To obtain such a polymer, the temperature rises to 200C. It requires careful handling due to toxicity, high heating of the mass, and harmful fumes. Application technical type in everyday life it is inconvenient and even dangerous due to the possibility of causing serious harm to health.

A “cold” variety has been developed for household use - jewelry compound. It is used for the manufacture of jewelry and interior products, as well as for household needs - repairs, gluing. The composition is very popular. The combination of glass transparency and increased strength makes it possible to “bury” entire plot pictures from nuts, pieces of glass and many other fillers in the depths of plastic.

Safety and Operation

Unusual spectacular Jewelry With various fillers and design developments for the interior (for example, self-leveling floors or furniture with various thematic compositions created in plastic) are very colorful and are in constant demand. Therefore, among professionals and amateurs of “handmade”, interest in “epoxy” does not decrease.

Manufacturers offer modern brands with increased comfort of use. After hardening, the mass is completely safe to use, has no odor, and does not emit toxic elements. Caution should be exercised when preparing and using a liquid or viscous substance while it is poisonous. The degree of toxicity depends on the qualitative and quantitative composition of the mixture. “Epoxy” is especially dangerous when hot. In contact with skin, the drug can cause irritation, dermatitis and even burns. When inhaling vapors, the mucous surfaces of the respiratory tract and eyes are irritated; the fumes can cause poisoning. But if certain principles are followed, working with the material is not dangerous.

Apply in radio and electrical engineering as dielectrics and insulating material; in varnishes, paints, putties, for adhesives, impregnations, etc.

It turns out liquid epoxy resins by condensation of epichlorohydrin with dihydric alcohols or phenols, more often with diphenylolpropane (diane, various brands of ED, E; abroad, brands of EPON), with resorcinol (epoxy-resorcinol, various brands of RES). Hardeners - amines (hexamethylenediamine, polyethylene polyamines, triethylene tetramine), acid anhydrides (maleic, phthalic, succinic), acids, diisocyanates.

Chemical properties. The reactive epoxy and hydroxyl groups of epoxy resins react with hardeners, resulting in cross-linking of the molecules. Uncured epoxy resins are soluble in some organic solvents, cured are insoluble. The number of epoxy groups for ED-5, ED-6*, ED-37 resins is 11-20%, the content of volatile substances (mainly toluene) is 0.5-2.5%. A peculiarity of the use of epoxy resins is the need to cure them directly during use, which usually leads to the release of volatile ingredients into the air. The release of volatiles from paints and varnishes based on epoxy resins increases significantly when heated to 85°. From coatings that are a mixture of epoxy resins with polyamide resin, volatile compounds are released already at 40° (Gorshunova et al.). Resins E-181 and ED-5, when used, release epichlorohydrin, dibutyl adipate and diphenylolpropane into the air. The release of volatiles is noticeably reduced after heat treatment of the resin at 50° for 45-60 hours (Ovcharenko). Migration of the starting monomers (epichlorohydrin and diphenylpropane) into water occurs when ED-5 resin is drained into wastewater(Boltromyuk).

Toxic effect. The resorptive effect of epoxy resorcinol resins is higher than that of diane resins; in the latter, the higher the toxicity, the less molecular mass. Cured resins appear to have little resorptive action unless they contain residues of the original products. The greatest danger is caused by skin diseases that arise from direct contact and as a result of sensitization. Dermatitis is sometimes accompanied by irritation of the eyes and upper respiratory tract. The toxic effect is aggravated by the use of hardeners that have irritating and sensitizing properties (Alekseeva, Terentyeva; Mehl et al.).

Workers in the process of manufacturing and using epoxy resins complained of headaches, nausea, poor appetite, burning eyes, swelling of the eyelids, irritation of the upper respiratory tract, skin diseases (Hine et al.; In a study of about 500 workers with epoxy resins, a third of them Among them, diseases of the upper respiratory tract (rhinitis, pharyngitis, etc.) were found with a relatively short period of experience, increasing with lengthening. In 20%, lesions of the bronchopulmonary system were detected, and with an experience of 5 and over 10 years, diseases were noted in 29% of those examined. Cases have also been identified bronchial asthma, especially with 3-5 years of experience. The disease was preceded by bronchitis, often with asthmatic attacks. Those suffering from bronchitis show signs of damage to the heart muscle on the ECG. The examined workers had disorders of the gastrointestinal tract and liver (impaired protein, pigment and carbohydrate metabolism). Almost 20% of those examined suffered from conjunctivitis, for the most part in combination with skin lesions.

When using epoxy resins and hardeners, skin diseases are observed both through direct contact with them and when exposed to dust and volatile substances. The diseases manifest themselves in the form of itchy red spots, papular-vesicular rash, eczematous dermatitis, sometimes weeping eczema, as well as swelling, especially of the facial skin. Not only open, but also parts of the body covered by clothing are affected (Burn). The number of skin lesions is usually large: some authors believe that 75% of workers fall ill (Burn et al.; Siboulet; Grandjean; Welker; Hine et al.; Plescher et al.; Spasovsky et al.; ). Skin lesions were allergic in nature, which was confirmed by positive skin tests with diluted dian resin in almost 68% of workers (Gulko; Surkova, Saperova; Kerimova, etc.). Some mastics based on epoxy resins, for example mastics KD-1, BI-2, also cause skin diseases (Pushkar, Borisenko; Volodchenko).

When ED-5 and ED-6 resins were applied to the skin of female mice for 45 days, their estrous cycle was disrupted (Proshina).

Maximum permissible concentration. According to the recommendations of some authors, it should be set according to the content of epichlorohydrin in the air and somewhat lower than for epichlorohydrin itself. Thus, for epoxy resins, ED-5, ED-40, epichlorohydrin is recommended at 1 mg/m3; for E-181 and for resins EA-1 and DEG-1 0.8 mg/m 3 (Korbakova et al.; ).

Personal protection. Preventive measures. Respiratory protection from volatile substances and aerosols released from epoxy resins and all compositions containing it during curing, heating, and processing. If it is necessary to work in poorly ventilated spaces, use forced-feed hose gas masks clean air. Sealed glasses. Gloves, sleeves, aprons made of polyethylene, chlorosulfone polyethylene. Use of protective pastes such as KHIOT-6, “invisible gloves”, “biological gloves”, siloxane ointments, IER-1 paste, etc. Remove adhered resin from the skin immediately (with soft paper), and then wash off with warm water and soap.

Mechanization of the preparation of epoxy resins and their compositions and elimination of direct contact of workers with epoxy resins and all materials containing them; limiting the content of the most dangerous volatile impurities in epoxy resins. See Kardashov et al.; “Industrial safety regulations. sanitation when working with epoxy resins and materials based on them,” approved. Central Committee of the Trade Union of Aviation and Defense Industry Workers 9/VIII 1962; “Sanitary rules when working with epoxy resins”, M., 1961; guidelines “Issues of occupational hygiene and toxicology in the production and use of epoxy resins”, L., 1961.

Preliminary and periodic (by a therapist once every 24 months and by a dermatologist once every 6 months) examinations when obtaining and using epoxy resins, adhesives, etc.

In animal experiments epoxy resins UP-612, UP-632, UP-629, diepoxy resins did not show irritating and sensitizing effects, but signs of their penetration through the skin were found (Kharchenko, Mishchenko).

For people who worked with epoxy compound EK-242, chronic bronchitis was detected. The concentration of epichlorohydrin in the air significantly exceeded the permissible limit. Skin diseases manifested themselves in the form of dermatitis. EF compounds And EPF-2 have an irritating and sensitizing effect (Pushkar, Borisenko; Zagidullin). When heated EPM-2 compound It is recommended to set the maximum permissible concentration for epichlorohydrin to 1 mg/m3.

Fiberglass metholon-E(with 30% modified epoxy resin) when heated, releases epichlorohydrin and chlorinated hydrocarbons (Dvoskin et al.).

Epoxy resins have been used in various industries for over 50 years. This name includes synthetic organic, partially polymerized compounds of viscous consistency. The resins themselves are non-volatile and non-toxic; in a closed container they remain fluid for a long time. Hardening of the resin occurs in the presence of hardeners. Polymerization catalysts pose a health hazard.

The health risks of epoxy

Aliphatic polyamine and polyamide compounds are used as polymerization catalysts. Penetration of toxic reagents into the human body when working with epoxy is possible through the skin, through inhalation of vapors or dust. Episodes of accidental ingestion of epoxy resin components are sometimes recorded.

Epoxy resin poisoning can be acute or chronic depending on the duration of exposure and the concentration of the toxic component. Acute intoxication results from ingestion of the toxin or prolonged inhalation of vapors. People who constantly work with epoxy are more likely to develop chronic intoxication caused by the regular intake of poison into the body.

Symptoms of poisoning

In case of poisoning with epoxy resins, the organs that are in direct contact with the toxic substance are primarily affected.

A set of symptoms that occur when the mucous membranes of the eyes are damaged:

burning sensation in the eyes;
redness of the eyes;
lacrimation;
swelling of the conjunctiva and cornea;
unfocused look.

If the respiratory tract is damaged, the victim experiences:

hoarseness of voice;
acrocyanosis;
fluttering of the wings of the nose;
dyspnea;
respiratory failure;
swelling of the airways.

Patients with signs of inhalation intoxication show increased anxiety and often have a fear of death.

With constant contact with epoxy resins and inhalation of small quantities of volatile components, it develops chronic form poisoning with signs of systemic damage to the body.

In almost every case, chronic bronchitis is detected. Simultaneously with the pathological process in the lungs, signs of disorders of the nervous system also appear. Patients become emotionally unstable, prone to expressive reactions to current events, and capricious. Among the typical complaints of patients with developing neurotoxicosis are increased fatigue and nervousness.

Due to poisoning, the development of bronchial asthma, chronic cholecystitis, gastritis, and colitis is possible. Volatile components in direct contact with the skin provoke allergic diseases.

The clinical picture of poisoning with epoxy resins due to accidental ingestion is dominated by symptoms of damage to the digestive system in the form of acute gastritis, gastroenteritis or enterocolitis.

Signs of systemic lesions are usually mild. The form and severity of clinical manifestations of poisoning depend on chemical properties and the amount of resin and/or its components received, as well as individual characteristics body and general condition the health of the victim.

From the gastrointestinal tract the following are observed:

stomach ache;
nausea;
vomit;
diarrhea mixed with blood.

Victims may complain of thirst, drowsiness, fatigue, general weakness, indicating the development of general acute intoxication and dehydration.

If the accidentally ingested resin has already been mixed with a hardener, the victim will show signs of mechanical damage intestines or acute intestinal obstruction. The overall clinical picture depends on the amount of mixture consumed and the location of the calculus formed during hardening of the resin. Such cases are characterized by the manifestation of a symptom complex known as “ acute stomach" In patients with suspected epoxy hardening in the intestinal lumen, surgical treatment is indicated.

The components of some resins are very aggressive and, upon contact with mucous membranes, cause chemical burns with the formation of a typical burn scab at the site of the lesion.

Treatment for intoxication and prevention

Acute inhalation poisoning with epoxy resins is diagnosed based on the patient's medical history. Standard laboratory tests are carried out to assess the general condition of the victim.

Toxicological studies are carried out only if there is a technical basis to perform the necessary tests.

In acute oral poisoning, the patient's condition is often aggravated by chemical burns along the digestive tract, intestinal obstruction, and sometimes intestinal perforation. To confirm the suspicion and determine the location of the lesion, an X-ray examination is performed. Depending on the condition of the victim, sigmoidoscopy or gastroscopy may additionally be performed.

If chronic poisoning is suspected, the following must be carried out:

blood chemistry;
analysis of the acid-base state of the blood.

Additionally, other studies may be prescribed depending on the prevailing symptoms.

In case of acute inhalation and contact poisoning, it is important:

Immediately stop further contact of the victim with the toxin and remove him to fresh air.
Rinse the patient's eyes running water, unbutton his clothes.
Sit or lay the victim in a comfortable position and call an ambulance.

If a person has noticeable difficulty breathing, choking or coughing, this may indicate developing swelling of the airways. In such cases, he needs to be provided with the most gentle, namely, a stable semi-sitting position.

The arriving ambulance team will act in accordance with the characteristics of the victim’s condition. First of all, he will be given drugs to eliminate swelling, and if necessary, he will be put on artificial ventilation.

Treatment of acute intoxication is carried out in a hospital setting; treatment tactics are selected depending on the type of lesion. Patients are prescribed medications that eliminate swelling and irritation of the mucous membranes. If necessary, the course includes antibiotics, painkillers and antipyretics.

For acute oral poisoning, systemic detoxification methods are used: