Skin diseases caused by chromium and its compounds
Introduction
Introduction to skin diseases caused by chromium and its compounds 1. Industrial application: metal chrome plating (25% to 50% chromic acid for chromium plating), chromic acid, chromium manganese salt or other industrial sectors such as pigment, tanning, printing and dyeing, photoengraving, alloy steel, matches, batteries, etc. Its dichromate class. Industrially, mainly used trivalent or hexavalent compounds, such as chromium oxide (Cr2O3), chromic acid (chromium trioxide, CrO3), chromium chloride (CrCl3), sodium chromate (Na2CrO4) or potassium chromate (K2CrO4), Potassium dichromate (K2Cr2O7) or sodium dichromate (Na2Cr2O7). 2. Physical and chemical properties: Chromium is a silvery white shiny metal that is hard and resistant to corrosion. Chromium can exist in the form of di-, tri- or hexavalent compounds. Divalent chromium is extremely unstable and easily oxidized to high-valent chromium. Under acidic conditions, Cr6 can be easily reduced to Cr3. Under alkaline conditions, low-valent chromium can be oxidized. Forming chromate. basic knowledge Sickness ratio: 0.05% Susceptible people: no specific population Mode of infection: non-infectious Complications: headache, anemia, asthma
Cause
Causes of skin diseases caused by chromium and its compounds
(1) Causes of the disease
Production and use of dichromate, chrome plated products, contact with acid chrome-plated yellow-brown fine mist to spread air, sensitization causes dermatitis.
(two) pathogenesis
The harm of chromium to humans mainly occurs in the process of chromium plating and the production and use of dichromate. Acidic chrome is used as a plating solution with concentrated chromic acid. When electroplating, hydrogen and oxygen can be generated on the electrode, and chromic acid is taken out. The yellowish brown fine mist is dispersed in the air to prepare dichromate and can be contacted with the powder in the tanning or chemical industry. In the offset printing, the liquid wiping machine containing chromic acid is often used, and the chromium-containing electric welding is used. When it is a stick, it may produce soot with a high chromium content. The cement contains traces of chromium, which is often the cause of dermatitis. Trivalent chromium compounds (such as Cr2O3) and metal chromium have not been reported to cause industrial poisoning or skin reactions. Trivalent chromium is not easily absorbed in the gastrointestinal tract, and it is easy to bind to proteins in the surface of the skin to form a stable complex, thus not causing dermatitis or ulceration. Hexavalent chromium compounds are the main pathogenic substances, and are intense at high concentrations. The oxidant has obvious local stimulating and corrosive effects and can be absorbed through the skin. The dichromate is stronger than the chromate, while the former is the most toxic to the sodium salt, and the hexavalent chromium compound is At low concentrations, it is a relatively common sensitizing substance, and it has been reported that contact with a solution containing only 0.08% of chromium can cause dermatitis.
Prevention
Prevention of skin diseases caused by chromium and its compounds
1. Environmental protection: The maximum allowable concentration of chromium trioxide, chromate and dichromate is 0.1 mg/m3, which is recommended to be 0.05 mg/m3, and a slot side suction device with sufficient wind speed is used.
2. Strengthen personal protection: such as wearing rubber aprons, gloves, protective glasses, masks, boots, etc. Sometimes you can apply proper skin protectant before work. The simpler method is to use soap immediately after exposure to chromium. Wash with water, wash hands with 10% sodium sulfite solution after work, then wash with water, sodium sulfite has a reducing effect, can make Cr6 become Cr3, lose the stimulation effect, can also receive the same with 5% sodium thiosulfate solution The effect, Samitz reports, is a suitable anti-chromium agent that is effective in preventing and treating harmful reactions of chromic acid or chromate.
If the skin is damaged due to careless work, even if it is extremely mild, immediately apply a disinfectant and protect it with an adhesive plaster.
Complication
Complications of skin diseases caused by chromium and its compounds Complications, headache, anemia, asthma
Long-term exposure to chromate dust or fog can cause headache, weight loss, anemia and kidney damage, bronchial asthma, etc., but it is rare. Foreign reports of hexavalent and trivalent chromium have carcinogenic effects.
Symptom
Symptoms of skin diseases caused by chromium and its compounds Common symptoms Nasal septum perforation, eczema, redness, mucous membrane damage, excessive secretion of catecholamine
Skin damage
(1) Contact dermatitis: Only a few patients were found among 534 workers in the electroplating factory investigated by Yang Guoliang, and several reports in China reported that the incidence of dermatitis was different, some as high as 29.3%. The author was in 1980 in 2 The investigation of electroplating factory found that the incidence of dermatitis in chrome plating workers was 15.1% (29/192). Skin lesions were more common in the back of the hand and wrist. The range was different and the edges were sharp. It was more common in summer and a characteristic of chrome dermatitis. The performance is that if there is a high degree of sensitivity, even if you leave the job, it will often last for a long time. If the eczema-like changes occur after prolonged unhealed or repeated attacks, the course of disease can last for several years. The diagnosis of chrome dermatitis and skin patch test are very important. The test is generally carried out with a 0.5% to 1.0% aqueous solution of dichromate.
(2) ulcer: also known as chrome ulcer, caused by chromic acid splash directly on the skin, more common in the back of the hand, finger back, forearm and foot, etc., single or multiple, ulcers from rice to soybean Size, sharp edges, high, round, irregular or linear, with dry gray-black sputum, no blushing around, often called "chicken-eye" ulcers, when continued to contact chromic acid, ulcers can invade And under the tissue, accompanied by pain, not easy to heal, after the formation of scars, according to our investigation in the electroplating factory, it is found that the ulcer site often has a history of scratches or damage, and then ulcers on the basis of injury; the skin has not been damaged It is not easy to have ulcers.
2. Mucosal damage
Mainly nasal mucosa, can occur catarrhal inflammation, erosion, atrophy, and even nasal septum perforation, mainly due to the stimulation of chromic acid mist and dust, it is said that the concentration of chromic acid in the air is 0.0001 ~ 0.001 mg / L, you can Caused by nasal mucosa changes, at present, because of the strengthening of protective measures, nasal septal perforation has been very rare, we only accounted for 7.4% (13/176 people) in the 1980 survey, and most of them are 15 to 20 years old Workers, their damage is old, and conjunctivitis and atrophic pharyngitis are now rare.
3. Systemic symptoms
Long-term exposure to chromate dust or fog can cause headache, weight loss, anemia and kidney damage, bronchial asthma, etc., but it is rare. Foreign reports of hexavalent and trivalent chromium have carcinogenic effects. Workers exposed to chromium oxide dust suffer from cancer. There are many lung cancer patients, but it has not been reported in China. Production and use of dichromate, chrome plated products, exposure to acid chrome-plated yellow-brown fine mist air and other chrome exposure history, related clinical manifestations and skin lesions.
Examine
Examination of skin diseases caused by chromium and its compounds
Check it out.
Diagnosis
Diagnostic identification of skin diseases caused by chromium and its compounds
Production and use of dichromate, chrome plated products, exposure to acid chrome-plated yellow-brown fine mist air and other chrome contact history. There are related clinical manifestations and symptoms of skin lesions.
