Mercury

Mercury (Hydrargyrum), Hg is a chemical element of group II of the periodic system D. I. Mendeleev, number 80, atomic weight 200,59. In natural conditions found in the form of sulphide (cinnabar)used for obtaining of metallic mercury. Mercury in normal conditions - liquid metal with silver glitter, temperature melting -38,8°, temperature boiling 357 degrees, the density 13,546 (at 20oC), valency in compounds-4-1, +2. With many metals mercury forms an amalgam. Evaporates even at room temperature. Exposure to mercury vapors possible in the extraction of cinnabar, the melting of mercury in the manufacture of precision instruments, in chemical laboratories of the pharmaceutical industry. Organic compounds of mercury pollution in the process of synthesis of insecticides (diethylmercury, diethylmercury) and their use in agriculture.
Mercury enters the body through the respiratory, digestive and intact skin. In the body forms a depot in liver, bone, where can re-enter the bloodstream. Slowly excreted by the kidneys (about 75%), gastrointestinal tract (about 25%), less saliva, milk and bile.
Acute poisonings occur in violation of safety in emergency situations (e.g. in case of a spill on large surfaces). While symptoms resembling foundry fever,fever, fever, inflammation of the Airways and lungs; mercury stomatitis (salivation, swelling and bleeding gums, mercury border of the gums, ulceration); loss of appetite, nausea, vomiting, abdominal pain, bloody diarrhea, atrophy of the liver, inflammation of the kidneys; symptoms of nervous system : headache, shaky, speech disorders, changes in gait.
Chronic poisoning (mercurialism) appear nervous disorders, the severity of which depends on the intensity of defeat. There are mercury elitism involving mental stimulation, vegetative shifts (game vasomotor with facial flushing, sweating, red dermographism); mercury tremor - at first small trembling fingers, then a sharp rise, shake the whole body, giperkineza. Noted increased salivation, sweating, tachycardia, the propensity to hypertension, gingivitis, stomatitis. These symptoms of varying severity, combined with nervous disorders.
Chronic toxicity adversely affect the course of pregnancy, delivery and lactation. Noted the high incidence of stillbirths. Children are born weak, poorly developed, sometimes sooner die.
In case of poisoning salts of mercury (mercuric chloride, calomel) is developing renal disease with symptoms anuria, azotemii, uremia, accompanied epileptiform seizures.
Organic mercury compounds (diethylmercury, diethylmercury) cause nerve syndrome with weakness, ataxia, unconscious state, significant intellectual disabilities.
The disease in case of poisoning by mercury vapor favorable if there is further their receipt. Schizoid and epileptiform diseases are very difficult to treat. Poisoning inorganic mercury compounds end sometimes fatal.
Treatment calm, psychotherapy, vitamins (thiamine, ascorbic acid, antihistamines drugs (diphenhydramine). In acute poisoning: antidote-dimercaptopropane (BAL) or unitiol (intramuscularly or subcutaneously with 5 ml of 5% solution). In asthenic conditions - barbiturates. When schizoid States chlorpromazine. Symptomatic treatment.
Prevention. Mechanization of processes of production and use of mercury, sealing equipment, effective ventilation. In labs all operations with an open mercury to produce a fume hood. Spilled mercury was going pear in the vessels with water. Polluted surface is treated with 20% ferric chloride. The air temperature in the premises should not exceed 18 degrees. Overalls - made of thick, lint-free podkreplennii tissue. Skin protection hand rubber gloves. At high concentrations of mercury - industrial gas mask. The most radical tool - replacement of mercury in different physical devices and equipment.
Preliminary and periodic (every 3 months) medical examination of working with mercury. Sanitary supervision for all objects of manufacture and application of mercury. Sanprosvet. MAC in the air of working premises 0.01 mg/m3. Special security measures - see ACC. the instruction on work with R. in laboratories, when seed dressing and so on).

  • Drugs mercury