Occupational mercury poisoning. Poisoning with mercury and its compounds

Clinic. Acute mercury vapor poisoning in industrial conditions is extremely rare: when cleaning mercury boilers and furnaces, as well as in accidents accompanied by massive release of mercury vapor into the working area. In acute poisoning, there is a metallic taste in the mouth, headache, general malaise, fever, vomiting, diarrhea. A few days later it develops hemorrhagic syndrome, severe stomatitis, sometimes with an ulcerative process on the gingival mucosa. Acute mercury pneumonia has been described.

In the clinic of occupational diseases, chronic intoxication resulting from prolonged exposure to metallic mercury vapors on the body is of primary importance. The severity of the clinical picture of the disease depends on the duration and massiveness of the mercury exposure, as well as on the individual sensitivity of the organism. Chronic mercury intoxication develops gradually and long time may be asymptomatic (compensated phase).

The initial stage of chronic intoxication proceeds according to the type of vegetative-vascular dystonia, neurasthenia. Syndrome is characteristic irritable weakness... Patients have a state of increased excitability and exhaustion of the nervous system. This is manifested by emotional instability, increased irritability, decreased performance, attention, sleep disturbance. Night sleep gradually becomes anxious, intermittent. Drowsiness is noted during the day. Memory decreases, headaches worried. One of the most characteristic symptoms mercury intoxication is considered a small-sweeping tremor of the fingers of outstretched arms. As the disease progresses, the severity and amplitude of the tremor increase. A distinctive feature of mercury tremor is its irregularity and asymmetry.

A characteristic is the state of increased excitability of the autonomic nervous system, primarily its sympathetic division; lability of the pulse, tendency to tachycardia, bright red diffuse dermographism, increased sweating. At the same time, disorders of the endocrine glands function are noted - hyperfunction thyroid gland, violation menstrual cycle, subsequently oligodysmenorrhea, sometimes - early menopause. The early symptoms of chronic mercury intoxication include pathological changes in the gums (loosening, bleeding).

The pronounced stage of chronic intoxication with mercury vapor proceeds according to the type of asthenovegetative (isychovegetative) syndrome. It develops in people with extensive experience in contact with high concentrations of mercury. Characterized by severe asthenia, almost constant headaches, persistent sleep disturbance, increased irritability, tearfulness, touchiness, tendency to depressive reactions. The syndrome of mercury erethism is characteristic: increased shyness, embarrassment, self-doubt, inability to perform their work in the presence of strangers due to strong excitement, accompanied by a vascular reaction, palpitations, facial flushing, sweating. This syndrome indicates significant disturbances in the emotional sphere.

In the expressed stage of chronic mercury intoxication, large-sweeping tremors of the hands, pronounced vegetative-vascular instability, instability of neurohumoral parameters, etc. are noted. There are marked affective disorders of the type of emotional incontinence, explosiveness. Such emotional disturbances are often combined with erethism. Often, against the background of increased excitability of the nervous system, pronounced hypothalamic dysfunction occurs. In this case, there are vegetative paroxysms with pain in the heart, palpitations, general tremors, hyperhidrosis, fluctuations blood pressure, numbness of the limbs, vital fear. Mercury diencephalo-ganglionitis is described.

Expressed forms of mercury encephalopathy almost never occur. These forms are characterized by organic damage to the central nervous system. Horizontal nystagmus, asymmetry of the innervation of the facial muscles, speech disorders such as dysarthria or chanting, atactic gait, adiadochokinesis, dysmetria, muscle tone disorders, increased tendon reflexes, rarely - foot clonus and abnormal foot reflexes are often observed. Pronounced changes in the psyche are described: depression, tearfulness, a sharp decrease in memory, a slowdown in associative processes, fears, obsessive thoughts... A schizophrenic syndrome has been described.

In the modern clinic of occupational intoxication, erased forms of mercury encephalopathy can occur. At the same time, the classical manifestations of intoxication described above are absent or are of a mild character and are long regarded as functional changes in the nervous system. Only careful dynamic observation, lack of effect from therapy, slow progression allow thinking about the organic nature of the process. Paraclinical studies of such patients reveal changes in EEG, EMG, rheoencephalography, etc., characteristic of encephalopathy.

Changes in internal organs during chronic mercury intoxication are usually dysregulatory in nature and proceed as viscero-neuroses. The most often noted are intestinal dyskinesias, gastritis, functional disorders of the cardiovascular system, kidney irritation (traces of protein in the urine). There is a violation of thermoregulation. A tendency to lymphocytosis, leukopenia, rarely a decrease in hemoglobin is described.

Mercury - a liquid shiny metal, boiling at 357.2 ° and solidifying at -38.9 ". Evaporates even at room temperature, and the higher the temperature, the more vigorously the evaporation process occurs. All these compounds are poisonous, with the exception of sulphurous mercury - cinnabar, difficult Soluble in body juices.Mercury is used in the manufacture of thermometers, barometers, precision graduated glassware, in the production of explosive mercury, in the extraction of gold from mineral ores, in the manufacture of mercury rectifiers; it is used in step-down substations, in chemical laboratories, in the pharmaceutical industry, in the application mercury pumps (for example, in the production of incandescent lamps).

In a production environment, metal mercury enters the body mainly through the respiratory tract in the form of vapor. Part of the mercury that has entered the body is retained for a long time and forms a depot mainly in the liver, kidneys and bones, from where mercury can enter the blood. Mercury is excreted from the body by the glands (saliva, sweat, and breast milk), but mainly in urine and feces. Mercury is often found in urine when all other symptoms of mercury poisoning are expressed to an insignificant degree.
Highlighting mercury from the body occurs slowly: there were cases of detection of mercury in urine after 4 months and even a year after the termination of work.

Sharp poisoning develop when significant amounts of mercury vapor are rapidly ingested into the body, which can occur when large quantities are spilled, when explosive mercury explodes in an enclosed space, when mercury is openly heated, and when the temperature in a room with open mercury is significantly increased.

With acute poisoning phenomena on the part of the digestive organs predominate: sharp stomatitis, diarrhea mixed with blood and fetid feces, tenesmus and stinging pains in the abdomen, sometimes vomiting.

Professional mercury poisoning in most cases, they are chronic, mildly expressed, and painful symptoms are manifested mainly from the nervous system, on which mercury has a selective effect. There are two phases of mercury poisoning: the first is the excitation phase and the second is the inhibition phase. The earliest symptom is tremor. It begins imperceptibly in the form of a small tremor of the fingers, then goes to the eyelids, lips, tongue, and in severe cases to the whole body.

Tremor intensifies with excitement and voluntary movements, it stops during sleep and decreases when the patient is at rest. Movements that require precise coordination (drawing, writing, bringing food to the mouth, etc.) are especially difficult. Sometimes neuralgic pains, anesthesia, paresthesia are observed, and sleep disturbances are also noted. Mercury erethism is understood as a kind of change in the psyche: increased mental excitability, accompanied by painful shyness and timidity, especially with strangers: the patient's face turns red, the movements become awkward.

The patient notes the rapidly advancing fatigue, headache; his working capacity decreases; worsens. Drowsiness or insomnia is also observed.

Unreasonable fears, forgetfulness. On the part of other organs in case of mercury poisoning, stomatitis, gingivitis and, in some cases, colitis, decreased gastric secretion, and hepatitis should be noted. There is a dysfunction endocrine systemss - enlargement of the thyroid gland, dysfunction of the sex glands; trophic disorders - brittle nails, hair loss.
Recently have a place only mild cases of mercury poisoning, expressed in the phenomena of increased vegetative excitability.

Prevention of mercury poisoning... The most radical way to combat poisoning is to replace mercury, where it is used, with less harmful substances. In some industries this has already been achieved (in the production of felt hats and felt boots).

Surface tablesused for working with mercury, must be smooth and have a slope for mercury to drain into a vessel with water. Cabinets and laboratory benches must be installed so that they are at a sufficient height from the floor (to be able to clean up spilled drops of mercury) or firmly attached to the floor to prevent the possibility of mercury penetration under them. Floors must be impervious to mercury; in industries where it is possible according to the conditions of technology, the floors are best covered with linoleum.

Transition from the surface sex to the wall should have a rounding - so that the edges of the linoleum are slightly raised in order to avoid mercury getting into the cracks. The walls are painted with oil or nitro enamel paint. Purification and distillation of mercury is allowed only in specially designated isolated areas. The maximum permissible concentration of mercury in the air of working rooms is 0.01 mg per 1 m3. Persons working with mercury should be provided with protective clothing, soap and towels for washing hands. Careful oral and dental care is also required. Applicants for work must undergo preliminary and periodic medical examinations.

Workers can be exposed to mercury in the following conditions: at mercury mines and factories, in the production of measuring instruments (thermometers, barometers, isometers, etc.), X-ray tubes, quartz and electric lamps, mercury rectifiers, mercury pumps, detonating mercury and pharmaceutical drugs; when amalgamating various metals.

Mercury compounds are used in anti-rot and mold-resistant paints, used to combat fungal infection of seeds, bulbous and other plants. The maximum permissible concentration (MPC) of mercury in the air of the working area is 0.01 mg / m 3.

Mercury enters the body through the respiratory system, gastrointestinal tract. Determining the level of mercury in urine is of great practical importance. At the same time, it should be borne in mind that the amount of mercury in urine does not correspond to the severity of intoxication, but depends mainly on its concentration in the inhaled air, i.e. a person can be a "carrier" of mercury without the risk of developing intoxication.

Pathogenesis. Mercury belongs to the group of thiol poisons. Once in the body, it combines with proteins, circulates in the form albuminates, disrupts protein metabolism, the course of enzymatic and reflex processes, is a source of afferent impulses entering the cerebral cortex

Chronic intoxication. Occurs in workers in conditions of prolonged contact with mercury. Depending on the severity of the pathological process in the clinical course of chronic mercury intoxication, three stages are distinguished: initial (functional), moderately pronounced changes and pronounced.

The initial stage, or the stage of "mercury" neurasthenia, is characterized by low symptoms and rapid reversibility. Patients have general malaise, headache, tearfulness, memory loss, sleep disturbance. Night sleep, as a rule, is anxious, intermittent, often with frightening dreams, during the day there is drowsiness, even during work. All this is accompanied by unpleasant sensations of a metallic taste in the mouth, profuse salivation. On examination, attention is drawn to the emotional instability of the patient and the severity of autonomic disorders.

The stage of moderately pronounced changes usually develops in those who have long experience of work in contact with mercury, or in the case of a late start of treatment for patients with signs of intoxication. Patients develop severe weakness, persistent headaches, insomnia, increased irritability, tearfulness, a tendency to depressive reactions. Symptoms of emotional lability gradually increase: unreasonable laughter, shyness, increased embarrassment. The patient becomes timid, absent-minded, it is difficult for him to do work in the presence of strangers. All this is observed against the background of a pronounced functional disorder of the nervous system, proceeding according to the type of asthenoneurotic or astheno-vegetative syndrome, and resembles the symptoms of "mercury" erethism.

A characteristic symptom of chronic mercury intoxication is a tremor of the fingers of outstretched arms, which is of a fickle nature and is most often detected with general excitement of the patient. With the progression of intoxication, the tremor becomes large-sweeping, it interferes with precise movements. The syndrome of irritable weakness is accompanied by an increase in the excitability of the autonomic nervous system, primarily its sympathetic part.

This is manifested by pulse lability, a tendency to tachycardia, arterial hypertension, instability of cardiovascular reactions, the appearance of bright red persistent dermographism, erythema spots on the chest and neck with excitement, increased sweating. Vegetative disorders are combined with disorders of the endocrine glands (thyroid, genital). In women, hypermenorrhea is more often observed, turning into hypomenorrhea. The constant symptoms of mercury intoxication include changes in the gums: looseness, bleeding, which later turn into gingivitis and stomatitis.

At the stage of pronounced changes, toxic encephalopathy, patients note the appearance of persistent headaches without clear localization, complain of constant insomnia, disturbed gait, weakness in the legs. A state of fear, depression, memory loss and intelligence are observed. Hallucinations are possible. Intensive tremors of the fingers are often accompanied by chorea-like twitching in certain muscle groups. The tremor tends to generalize, spreads to the legs (tremor of the extended, raised legs with the horizontal position of the trunk). Microorganic symptoms are also noted: anisocoria, flattening of the nasolabial fold, absence of abdominal reflexes, difference in tendon and periosteal reflexes, impaired muscle tone, hypomimia, dysarthria. A schizophrenic-like syndrome may develop. Hallucinatory delusional phenomena, fear, depression and "emotional dullness" appear. Psychosensory disorders, changes in the body scheme, and twilight consciousness are noted. Toxic encephalopathy is difficult to treat even with active long-term treatment. The literature describes isolated cases of retrobulbar neuritis, periodic narrowing of the visual fields. With prolonged exposure to mercury, mercury deposits in the lens ("mercurialentis") are sometimes found.

Prevention. Additional medical contraindications for working with mercury are chronic, often recurrent skin diseases, diseases of the teeth and jaws (chronic gingivitis, stomatitis, periodontitis), chronic gastritis, diseases of the liver and biliary tract, peripheral nervous system, drug addiction, substance abuse, chronic alcoholism, schizophrenia and others endogenous psychosis.

Treatment should be comprehensive, differentiated, taking into account the severity of the pathological process. In order to neutralize and remove mercury from the body, it is recommended to use antidotes: unitiol, succimer, sodium thiosulfate. The most effective is unitiol, whose sulfhydryl groups react with thiol poisons, forming non-toxic complexes that are excreted in the urine. D-penicillamine is one of the complexing compounds that promote the elimination of mercury from the body, but its use due to side effects limited. It is advisable to include in the complex of therapeutic measures funds that improve metabolism and blood supply to the brain. With pronounced emotional instability and sleep disturbance, drugs from the group of tranquilizers are indicated, while small doses of hypnotics (phenobarbital, barbamil) are prescribed. Drug therapy should be combined with the use of hydro procedures (hydrogen sulfide, coniferous and sea baths), ultraviolet radiation, physiotherapy exercises, psychotherapy.

Pathogenesis. Mercury belongs to the group of thiol poisons. Once in the body, in particular in the blood stream, mercury combines with proteins and circulates in the form of albuminates. mercury disrupts protein metabolism and the course of enzymatic processes. All this leads to profound dysfunctions of the central nervous system, especially its higher sections. Mercury is the source of impulses to the cerebral cortex. As a result, there is a number of reflex disorders in the cortical-subcortical regions.

The formation of a pathological process in mercury intoxication occurs in phases and is characterized by a complex of neuro-regulatory and neurohumoral changes. In the initial period and further, as the pathology develops, when the adaptive defense mechanisms cannot block the action of the toxic agent, disorders develop in the vegetative parts of the central nervous system. Moreover, in accordance with functional state the cerebral cortex changes the excitability of the analyzers (olfactory, visual, gustatory). In the future, the exhaustion of cortical cells increases, disinhibition of the subcortical and, first of all, the hypothalamic departments is revealed. All this leads to a weakening of internal active inhibition and inertia of cortical processes. As a result, the symptoms of "mercury neurosis" corresponding to the clinical picture of mercury intoxication, as well as disorders in cardiovascular system, digestive tract and metabolic processes. As intoxication grows, disturbances in the neurodynamic relationship between the cortex and the optic hillock, as well as between various structures of the motor analyzer, including the subcortical ganglia and cerebellum, are revealed.

Mercury can damage the nerve-to-muscle transmission apparatus in motor nerves, causing disturbances in the extrapyramidal system as a whole. All this leads to disorders of complex functional connections, which are in charge of the automatism of the combined activity of various muscle groups.

The main route of penetration into the human body is inhalation. The mercury absorbed into the blood of the pulmonary capillaries circulates for some time in the form of mercury albuminates. Then it is deposited for a long time in the liver, kidneys, spleen. Overcoming the blood-brain barrier, it finds itself in cerebrospinal fluid and the brain, where it directly affects the cerebral cortex and the thalamo-hypothalamic region. Violation of the connections of the cortex with the visual hillock and the sub-hillock area is accompanied by a disorder of the mechanism of formation of emotional reactions. In addition, the accumulation of mercury is accompanied by inhibition of sulfur-containing enzymes, because it forms complexes with sulfhydryl groups, exerting a blocking effect on them.

Clinical picture acute and chronic mercury intoxication

Acute intoxication in production conditions it is rarely observed (in emergency cases, when cleaning mercury boilers and furnaces), develops within 1-2 hours after inhalation of high concentrations of mercury vapor and manifests itself in mild cases, mainly by neuropsychiatric symptoms (general malaise, weakness, headache, irritability, insomnia, irritability), as well as an increase in body temperature, the appearance of a metallic taste in the mouth, salivation, diarrhea, vomiting, stomatitis and signs of bronchitis and the gastrointestinal tract. In more severe cases, intoxication develops ulcerative stomatitis, hemorrhagic enterocolitis, toxic pneumonia, hepatitis and nephropathy.

Chronic intoxication vapors of metallic mercury in the clinic of occupational diseases is of primary importance and occurs among workers who have long-term contact with mercury. The clinical symptomatology of intoxication develops gradually and is manifested mainly by nonspecific lesions of the nervous system, which significantly complicates the diagnosis of early forms of chronic mercury intoxication, which may explain the insufficient detection of this occupational pathology.

The nervous system is early involved in the pathological process of the effect of mercury on the body and is clinically manifested mainly by functional disorders of the nervous system of the type of varying severity of asthenic-vegetative syndrome (ABS), which at a later stage of intoxication development can develop into organic pathology (encephalopathy).

Light ABC characterized by asthenic - neurotic complaints (mainly of hypersthenic character) and vegetative - vascular dysfunction with sympathetic - tonic orientation of vegetative - vascular reactions. The main complaints are headache, rapid fatigue, shallow sleep at night and noticeable drowsiness during the day at work, slight memory loss and tearfulness, irritability. Red dermographism, increased sweating of the palms of the hands, emotional instability, lability of the pulse and blood pressure with a tendency to tachycardia and hypertension, negative perverted Ashner-Danini reflex, tremor of the fingers of outstretched arms, small-amplitude and inconsistent, often detected only with excitement.

Moderate ABC - characterized by a significant increase in the severity of all of the above symptoms with the prevalence of irritable weakness and more pronounced sympathetic-tonic disorders: persistent headache, dizziness, insomnia, increased irritability, tearfulness and emotional instability, excitability, timidity, inadequate embarrassment, self-doubt appears at work, especially in the presence of unauthorized persons, while, due to strong excitement, there is a pronounced vascular reaction with increased heart rate, facial flushing and general hyperhidrosis, which indicates the development of so-called "mercury erethism". Tremor intensifies, which becomes permanent against the background of developing intentional tremors of the fingers, which makes it difficult to perform small works.

Pronounced ABC - characterized by increased asthenization with an increase in the parasympathetic orientation of vegetative-vascular disorders with paroxysms (fainting, pain in the heart, general hyperhidrosis, cold extremities, pallor of the skin and a pronounced emotional reaction): constant headache, sharp irritability, tearfulness, tendency to depression , decreased range of interests, changes in mood, hypochondriacal reactions, general weakness, lethargy, tendency to bradycardia and hypotension, decreased skin temperature on the fingers with a positive cold test, decreased muscle strength in the hands with a positive test for fatigue and tone of the flexor and extensor muscles of the hand ... The tremor becomes large - sweeping, tends to generalize and spread to the legs, head, intentional tremor increases. Microorganic symptoms appear: anisocoria, weakness of the internal muscles of the eyes during convergence, nasolabial asymmetry, slight deviation of the tongue, slight anisoreflexia, nystagmoid.

Along with neurological symptoms in chronic mercury intoxication, changes in other organs and systems of the body can also be detected: loosening and bleeding of the gums, gingivitis, stomatitis, periodontal disease, hair loss, brittle nails, hyperfunction of the thyroid gland, impotence, there is a violation of carbohydrate, protein and enzymatic function liver, kidney irritation phenomenon. Possible functional disorders of the cardiovascular system, occurring in the form of neurocirculatory dystonia (on the ECG, a decrease in the voltage of the T wave, QRS complex, signs of incomplete blockade of the His bundle and left ventricular hypertrophy, slowing of intra-atrial conduction), intestinal dyskinesia, gastritis. In some cases, there may be violations of thermoregulation, manifested by persistent subfebrile condition; on the part of the blood - lymphocytosis and monocytosis, less often anemia and leukopenia, a decrease in the content of sulfhydryl groups.

Early diagnosis chronic mercury intoxication is based mainly on clinical data, taking into account the specific working conditions of the patient, anamnesis, the dynamics of the development of the disease. Confirmation of the diagnosis of intoxication can be the presence of mercury in the biospheres - urine, blood, and hair.

The excretion of mercury in the urine indicates its circulation in the body and the presence of a mercury depot (mainly the liver, kidneys, spleen, brain); mercury in blood reflects recent exposure, and mercury in hair is indicative of chronic exposure and may reflect the degree of risk of intoxication.

Depending on the severity of neurological manifestations, the following 3 stages of development of chronic mercury intoxication are distinguished:

1 stage of intoxication(initial or mild degree) - functional ("micromercuralism") stage and is characterized by mild asthenic - vegetative syndrome with small-amplitude tremor and mercury content in urine from 150 to 300 mcg / l; in the blood 7.5-15.0 mcg% and in the hair 2-8 mg / kg.

2 stage of intoxication (moderately pronounced degree) - characterized by the progression of functional disorders of the nervous system, the appearance of micro-focal symptoms and manifested by a moderately pronounced asthenic-vegetative syndrome with a possible transition to encephalopathy and large-spreading intentional tremor, as well as initial polyneuropathy; the content of mercury in urine is 300-600 mcg / l, in blood - 15.0-30.0 mcg%, in hair 8-30 mg / kg.

III stage of intoxication(pronounced degree) - occurs rarely, organic neurological symptoms appear against the background of pronounced asthenic-vegetative syndrome - encephalopathy (asthenoorganic, astheno-depressive and hypothalamic syndromes) with significant large-sweeping and intentional tremor with a tendency to generalization, polyneuropathy; the content of mercury in urine is 600 μg / l or more, in blood - 30.0 μg% or more, in hair - 30 mg / kg or more.

Treatment. The main task is the mobilization of mercury compounds from the depot, neutralization and rapid elimination from the body. The antidote is unitiol, which is injected intramuscularly in the form of a 5% solution of 5.0 every 8-12 hours in the first three days after poisoning, in the following days - once a day for two weeks. Unithiol inhalation is used. The elimination of mercury from the body can also be enhanced by sodium thiosulfate with intravenous administration of a 30% solution of 20.0; D - penicillamine 0.15x3 times.

The main therapeutic measures should be aimed at removing mercury from the body, general detoxification, symptomatic and general strengthening therapy. To bind and remove mercury from the body, intravenous infusions of a 30% solution (20 ml) of sodium hyposulfite are used, for a course of 15-20 infusions or a 5% solution of unithiol, 5 ml each intramuscularly, as well as oral administration of succimer 0.5 three times a day or cuprenil on average at a dose of up to 600 mg per day for 5-10 days, always under the control of urine analysis for mercury; the ingestion of sulfate - ion in the form of an aqueous solution of sodium sulfate at the rate of 25 mg per kg of body weight is shown (usually an aqueous solution of sodium sulfate 1.4-2.1 g is given per 200.0 once a day for 1-1.5 hours before meals, a course of at least one month), methionine or cesteine, and hydrogen sulfide baths are also recommended.

Drug therapy with a predominant lesion of the nervous system, it should be aimed primarily at normalizing cortical and subcortical neurodynamic disorders, taking into account vegetative-vascular disorders (sympathetic or parasympathetic response): valerian, motherwort, meprotan, amizin, finozepam, pyrroxan, anaprilin; with encephalopathy - aminalon, riboxin, stugerone; in the presence of polyneuropathy - vitamins of group B, dibazol, biostimulants, physiotherapy and reflexotherapy are also shown. Symptomatic therapy is also carried out taking into account those available from other organs and systems of the body, while observing a strictly differentiated and individual approach.

Prevention. Improvement of technological equipment, automation and mechanization of basic production processes, maximum sealing of equipment. Functioning of general and local ventilation. Automatic control methods for air pollution in the workshop and personal protective equipment for workers should be introduced. Particular attention should be paid to improving workwear, safety footwear and methods of neutralizing them. Cleaning and neutralization of equipment surfaces, walls, floors. Regular cleaning of the premises and periodic demercurization with a 20% solution of ferric chloride or potassium permanganate. Spilled mercury must be carefully collected. All work with open mercury, its heating must be carried out in fume hoods.

Prohibition of eating and smoking in the workshop. Anti-alcohol propaganda. Compliance with the regime of work and rest. Oral cavity sanitation. Organization of preventive nutrition, which provides for a sufficient content of vitamins, juices, fresh vegetables. Use mineral waters containing sulfates during operation. Preliminary and periodic inspections

Additional medical contraindications for recruitment in contact with mercury and its compounds are:

chronic diseases of the peripheral nervous system;

drug addiction, substance abuse, including chronic alcoholism;

severe autonomic dysfunction;

diseases of the teeth and jaws (chronic gingivitis, stomatitis, periodontitis, periodontal disease);

pronounced, often exacerbated forms of chronic gastritis;

chronic, often recurrent skin diseases;

schizophrenia and other endogenous psychoses.

Medico - social expertise, labor rehabilitation and medical examination.

Expert tactics in relation to patients with chronic mercury intoxication should be determined taking into account the characteristics clinical development and the course of the disease, its severity, the presence of concomitant diseases, as well as taking into account the specific sanitary and hygienic working conditions at the workplace. At stage 1 of the disease (mild intoxication), only temporary suspension from work in contact with mercury vapor is recommended, no more than two months, preferably with the subsequent addition of a labor leave. In the event that the treatment and temporary suspension from the main job is a reverse development of the manifestations of intoxication, it is possible for the employee to return to his previous job subject to dispensary observation and safe sanitary and hygienic working conditions, i.e. going back to work should be done very carefully.

In case of relapses of intoxication after returning to their previous job, as well as in cases where all therapeutic and prophylactic measures do not eliminate clinical manifestations intoxication, it is necessary to refer the patient to MSEC to determine the degree of disability according to occupational diseaseif the qualifications of the employee are reduced. Employment without contact with any toxic substances.

At 2 (moderately pronounced degree of intoxication) and especially III (pronounced degree of intoxication) stages of chronic mercury intoxication, contact with mercury should be completely terminated. Patients are rationally employed through the MSEC and a disability group for occupational disease is established due to persistent disability in most cases in the presence of severe forms of encephalopathy.

Block 3.

Patient P., 42 years old, works in the production of batteries. Was taken to hospital by ambulance due to severe abdominal pain. From the anamnesis it was found that even before working at the battery plant he had a peptic ulcer duodenum... Over the next 20 years, there were no exacerbations, which was confirmed by gastrological studies ...

Diagnosis: Chronic lead intoxication, severe form. The diagnosis was made on the basis of data on the patient's place of work, patient complaints, blood test data

Additional research: to conduct a sanitary and epidemiological examination of the place of work for the maximum permissible concentration of lead, conduct a urine analysis, diagnose the nervous system for the presence of neurological syndromes

Treatment: Complex therapy in the form of 3 cycles intravenous administration 20 ml of 10% solution of tetacin-calcium. It is possible to add in the subsequent D-PAM at a dose of 600-900 mg per day under the control of blood, indicators of porphyrin metabolism. Inpatient treatment.

Option 5

Block 1

2) reticulocytes

5) the ability to penetrate intact skin

6) marcans, parksineon

7) in bones

8) red

9) asthenovegetative

Block 2

Intoxication with these drugs is possible when they are used in agriculture and in industry, when pickled grain is consumed.

Clinic. Chronic poisoning develops after a more or less long latent period (on average 2 months). The first signs of the disease are manifested in the form of nausea, vomiting, trophic lesions of the oral cavity (the gums are loosened, bleeding, salivation increases sharply, and gingivitis stomatitis often develops). Polydipsia (excessive thirst) and polyuria are common symptoms. Patients drink 2-6 liters of liquid per day and excrete the same amount of urine. Zimnitsky's test reveals isostenuria in these patients. Some patients complain of pollakiuria and pain during urination. Almost half of the patients have urinary tract irritation: macroalbuminuria, the presence of leukocytes in the urine, microhematuria. In severe cases, the opposite is possible - oliguria, azotemia. Death from uremia is possible.

Pathogenesis. The mercury compounds contained in the air enter the respiratory tract, are absorbed into the blood and circulate in the body, then are quickly adsorbed and retained in them for a long time. The greatest amount of mercury accumulates in the liver, kidneys, brain, in smaller amounts it is contained in the spleen, lungs, heart. There is a violation of carbohydrate, protein and fat metabolism. Thus, mercury compounds can interfere with tissue metabolism. important organs. Treatment. The main task of treatment is the mobilization of mercury compounds from the depot, neutralization and rapid elimination from the body.
The use of unitiol contributes to the successful solution of this problem. The drug is administered to patients intramuscularly in the form of a 5% solution. Unitiolo inhalation is also used. Vitamin therapy is indicated - C and group B. With stomatitis - rinsing with 0.25% solution of potassium permanganate or 35 boric acid... Patients with chronic mercurialism are shown spa treatment. If the drug gets inside, it is necessary to wash the stomach with a weak solution of potassium permanganate and give an adsorbent - activated carbon or "white water" (2 egg whites per glass of water) and a laxative.

Block 3

Chronic fluoride intoxication.

When initial stage intoxication is recommended to transfer to another temporary job and appropriate treatment. In case of persistent manifestations of hepatitis, polyneuritis, as well as at stage II of bone fluorosis, the severity of other lesions of the musculoskeletal system with persistent pain syndrome and dysfunction, further work with fluorides is contraindicated. Women during pregnancy and lactation should be excluded from work with fluoride.

Option number 6

1. Indicate the distinguishing feature of mercury during its evaporation: colorless

2. The amino and nitro compounds of benzene does not include: styrene

3. Where should white phosphorus be stored: under water

4. The most dangerous route of lead penetration: respiratory system

5. Preventive measures for pesticide intoxication: replacement of hazardous pesticides with less hazardous

6. Pneumocaniasis developing when working with manganese: manganocaniasis

7. What form of lead polyneuritis is the development of paresis and paralysis: motor

8. What the skin is treated with when phosphorus gets in: 5% copper sulfate solution

9. The norm of methemoglobin in erythrocytes: no more than 1.0-2.5%

10. When poisoning with carbonates, the symptoms of defeat come to the fore: skin and mucous membranes

From the air, mercury vapor is absorbed in the lungs by 85-90%. Particles of erosion, containing mercury salts, settle in the respiratory tract, dissolve in their secretions, and are partially swallowed, entering the stomach. In the form of mercury albuminates from the lungs and the gastrointestinal tract, mercury is carried by the blood throughout the body, accumulating in organs with a high blood supply - the kidneys, liver, thyroid gland, and the brain. The distribution of this liquid metal in the body is due to the nature of the mercury compound and the way it is supplied. In case of poisoning with mercury vapor, its maximum accumulation is noted in the lungs, brain, kidneys, liver and heart. In people living in areas of atmospheric mercury pollution, there is a predominance of diseases of the respiratory system, nervous system, sensory organs, blood circulation, genitourinary, endocrine systems, nutritional disorders and metabolic disorders.

The penetration of mercury ions into the cell is preceded by damage to the cell membrane as a result of interaction with sulfhydryl groups of proteins, which is accompanied by a violation of its structure. Having penetrated into the cell, mercury accumulates in the nucleus, microsomes, cytoplasm, mitochondria, excluding reactions with sulfhydryl, carboxyl amino groups from biochemical processes. Protein, nucleic acid, energy metabolism, stability of tissue lipoprotein complexes are disturbed. The high affinity of mercury for nucleic acids, especially transport RNA, is accompanied by pronounced gonadal and embryotoxic effects.

The clinical picture of intoxication depends on the form of the mercury compound, the way it enters the body and the volume of the absorbed poison.

Acute poisoning of people with mercury vapor occurs during accidents, fires at mercury mines and factories, or as a result of gross violations of safety regulations. The clinical picture of inhalation poisoning develops after 8-24 hours and includes general weakness, headache, pain when swallowing, fever, catarrhal phenomena from the respiratory tract (rhinitis, pharyngitis, less often bronchitis). Then hemorrhagic syndrome joins, soreness of the gums appears, pronounced inflammatory changes in the oral cavity (the so-called mercury stomatitis with an ulcerative process on the gum mucosa), abdominal pain, stomach disorders, signs of kidney damage.

In children, a few hours after the start of inhalation of mercury vapors, severe pneumonia may develop - coughing, shortness of breath, cyanosis, febrile temperature appear. With severe intoxication, pulmonary edema is possible. At the same time, symptoms of damage to the gastrointestinal tract (frequent loose stools) and the central nervous system (drowsiness, alternating with periods of increased excitability) appear.

In the gastrointestinal cycle, 10-30% of water-soluble inorganic mercury compounds and up to 75% of organic compounds can be absorbed, while metallic mercury is absorbed very poorly (about 0.01%). At the same time, organic mercury compounds, due to their high lipoidotropy, easily penetrate into tissues through histohematogenous barriers, including through the blood-brain barrier in the central nervous system, as well as through the placental barrier into the fetus.

Acute poisoning with inorganic mercury compounds (dichloride, cyanide, mercury nitrate) occurs when they are mistakenly ingested or used for suicidal purposes. The most toxic is mercury dichloride (mercuric chloride). Lethal dose sublimate - 0.5 g. Admission is accompanied by burning pain in the mouth, pharynx, esophagus, in the stomach, along the colon. Headache, profuse salivation, bad smell from the mouth, redness and bleeding of the gums, stomatitis, necrotic plaque on the mucous membrane of the tongue, pharynx and pharynx. Laryngeal edema is possible. Dyspeptic phenomena are observed - nausea, prolonged, persistent vomiting, diarrhea with mucus and blood, tenesmus, along the mucous membrane of the stomach and duodenum, multiple manifestations. The body temperature often rises. In severe cases, necrotizing nephrosis develops. Polyuria is replaced by progressive oliguria. Albuminuria, hematuria are observed. Damage to the kidneys by mercuric chloride is manifested by continuous necrosis of the epithelium of the convoluted tubules. The early onset of anuria is regarded as an unfavorable sign of the development of the syndrome of "sublimate kidney", leading to death on the 5-6th day. In relatively mild cases of poisoning, the impaired functions are restored after 2-3 weeks.

Sodium chloride, acids, alcohol and fats increase the solubility of mercuric chloride. Reception of salty, fatty, acidic foods and alcohol with this poisoning is contraindicated, the nicotine poisoning sharply aggravates.

In chronic intoxication with mercury vapors, the development of the clinical picture is determined by the intensity of exposure and the individual characteristics of the organism. In general, chronic intoxication develops gradually and for a long time do not have obvious signs of the disease. The initial stage proceeds according to the type of neurasthenia and vegetative-vascular dystonia. In a pronounced stage, a psychoneurotic syndrome is noted. The transitional state from the compensatory phase to the initial stage of mercury poisoning is called "micromercurialism". A strict delineation of the stages of the disease is difficult, since as the severity of the symptoms of intoxication increases, they gradually turn into one another. Of great importance in this sense is the transition of the small-sweeping and asymmetric tremor of the fingers of the outstretched arms in the initial phase of mercurialism into the large-sweeping tremor of the arms, characteristic of the pronounced stage of chronic poisoning. This stage is characterized by emotional incontinence, explosiveness, hypothalamic dysfunction, vagotonic reactions and viscero-neurotic manifestations (pain in the heart, palpitations, intestinal dyskinesia, bladder, gastritis). In the stage of pronounced manifestations of intoxication, individual signs of encephalopathy are possible.

The first manifestations of mercurialism - increased fatigue, weakness, drowsiness, apathy, headaches, dizziness, bleeding gums - fit into the picture of "mercury neurasthenia". Over time, trembling ("mercury tremor") develops first of the fingers of outstretched arms, then the tongue, eyelids, and in severe forms - of the legs and the whole body. There is a state of increased mental excitability ("mercury erethism") in combination with rapid exhaustion of the nervous system and the appearance of timidity, fearfulness, general depression, and lack of confidence in their abilities. As the disease progresses, patients are extremely irritable, gloomy, and often cry. Sleep at night is disturbing, but during the day they are drowsy, often memory and attention are weakened. Hypersalivation observed in mercurialism, violation of the secretory function of the stomach, cyanosis, sweating, slow or rapid heart rate, increased urge to urinate are associated with the effect of mercury on the autonomic nervous system. In the initial stage, there are signs of increased excitability of her sympathetic department. This is manifested by tachycardia, bright red blurred dermographism and combined with hyperfunction of the thyroid gland.

The defeat of the peripheral nervous system proceeds as multiple neuralgias. Neurotic manifestations are characterized by pain in the limbs and in the area trigeminal nerve, mild distal sensory disorders. Facial asymmetry may occur. One of the important signs is weakening of the extensor strength on the predominantly working arm. Changes in the digestive organs are weak or absent, as are changes in the kidneys.

It has been established that non-specific manifestations of prolonged mercury intoxication may be observed in persons suffering from mercurialism. Thus, the phenomena of atherosclerosis, coronary disorders, liver and gallbladder lesions are diagnosed 5-7 times more often in those with manifestations of mercurialism than in those who have no mercury intoxication.

Certain difficulties arise in the diagnosis of micromercurialism. Many of his cases pass under the guise of respiratory diseases, often diagnosed as neurasthenia, hysteria, etc.

Recently, symptoms of micromercurialism have often been detected in industrial workers, employees of research institutes working under conditions of exposure to low concentrations of mercury (at the MPC level or several times higher than 0.01 mg / m3) for at least 8-10 years. In this case, the main manifestations of the disease are expressed in changes in the central nervous system.

Almost always there is a characteristic small and frequent tremor of the fingers of outstretched arms, bleeding gums, hypersalivation, gingivitis. From the side of the blood - a decrease in hemoglobin and the number of erythrocytes, leukopenia, a shift in the leukocyte formula to the left.

With micromercurialism caused by mercury, its inorganic compounds or organomercury compounds, there are no clear clinical differences in the symptoms of intoxication.

Treatment of mercury poisoning is a complex of specific pathogenetic, symptomatic, restorative physiotherapy.

The most radical and active method of treating mercury salt poisoning is extracorporeal detoxification - hemosorption, lymphosorption, hemodialysis, peritoneal dialysis.

Dithiol compounds, in particular unitiol, have an antidote effect. Applied in the form of 5 percent. solution subcutaneously or intravenously at the rate of 50 mg for every 10 kg of the patient's weight. On the first day, 3-4 injections are made every 6-8 hours, on the second - 2-3 injections, in the next 3-7 days - 1-2 injections, depending on the patient's condition. For chronic intoxication with mercury, treatment with inhalation of an aerosol of unithiol is effective. Highly dispersed aerosol 5% patients inhale a solution of unitiol 2 times a day, 15 ml. To eliminate the smell of hydrogen sulfide, characteristic of unitiol, 1-2 drops of menthol oil are added to it before inhalation. Treatment lasts 10 days, repeated courses are recommended. IN outpatient you can use the calcium-disodium EDTA salt of 0.5 g 3 times a day for 4 days, in the form of 2 courses with a week break.

Succimer is used for the treatment of subacute intoxication and as a means of individual prophylaxis, in which the complex-forming action of dithiol with succinic acid is successfully combined.

In acute poisoning with mercury, especially when its dissociating salts (mercury dioxide, mercury oxycyanide, mercury nitrate) enter the stomach, a metal antidote is given simultaneously with the introduction of unitiol (Strzhizhevsky). Hydrogen sulfide, which is part of the antidote, converts mercury compounds into insoluble sulfides, which are excreted in the feces. 100 ml of this antidote neutralizes up to 4 g of mercuric chloride. Before taking the antidote give to drink 200-300 g of water acidified with vinegar or citric acid. After 10 minutes, the stomach is washed through a tube with slightly acidified water, to which 100 ml of the same antidote can be added, until clear waters appear. After washing, a laxative is injected through a tube. In the absence of an antidote, immediately rinse the stomach abundantly with water with 20-30 g of activated charcoal or protein water (2 beaten egg whites per 1 liter of water), then give milk, egg yolk beaten with water, and then a laxative, rinse your mouth with 5 percent ... potassium permanganate solution or berthollet's salt solution.

Shown are high siphon enemas with a suspension of activated carbon and tannin.

Simultaneously with the listed detoxification measures, the fight against acute renal failure begins. Diuresis is forced by intravenous administration of isotonic sodium chloride solution, polyglucin, 5%. glucose solution, drip up to 4-5.5 liters per day, with diuretics (lasix up to 200 mg per day). Protein hydrolysates, colloidal suspensions, blood substitutes are introduced in large volumes. If necessary, conduct bilateral perirenal novocaine blockade, diathermy of the kidney area, surgical decapsulation of the kidneys.

Along with specific antidote therapy, general strengthening and toning agents for the nervous and cardiovascular system are widely used - strophanthin or corglikon, caffeine, cordiamine, mezaton, in case of collapse - norepinephrine in 5 percent. glucose solution intravenously, drip. Complex vitamin therapy, adaptogens, antihistamines are shown.

Physiotherapeutic methods of treatment are recommended: hydrogen sulfide baths, galvanic baths with sodium hyposulfite or sulfur, ultraviolet irradiation in combination with warm pine baths. It is advisable to treat at the resort (Matsesta, Pyatigorsk, etc.) with sulfur and hydrogen sulfide baths. It is recommended to include lipotropic substances and pectins in the diet.

The terms of treatment and rehabilitation of patients with both acute and chronic poisoning are delayed for a long time. This is because mercury compounds are slowly eliminated from the body. Thus, the half-life of methylmercury is on average 75 days, and that of inorganic compounds is 42 days. Patients with chronic mercury intoxication of the first stage need inpatient treatment for an average of 2-3 weeks. After an additional, up to 2 months, stay on sick leave allowed to start work with careful dispensary observation... In the presence of symptoms of asthenization, work with mercury is contraindicated.

The following interpretation of the results of analyzes of biosubstrates for mercury content is adopted. In the blood, the norm of the mercury content is in the range of 0.3-0.7 μg%, the content above 1 μg% is considered elevated. The permissible level of mercury in urine during occupational exposure to its vapors is 10 μg / l. Normally, the excretion of mercury in the urine can reach 5-7 μg / day. In hair, the upper limit of the safe mercury content is considered to be 5 μg / g.

Among the organizational measures carried out by the sanitary and epidemiological service in all cases of mercury pollution, it is necessary to highlight the establishment of the boundaries of the focus and levels of pollution, the assessment of possible consequences for the health of the population when staying in a polluted atmosphere, the decision on the need for medical examination and observation of victims, the definition of the scope of a safe work of personnel conducting demercurization, assessment of the effectiveness and sufficiency of demercurization and the possibility of further functioning of contaminated facilities.

The health risk assessment of persons who were in the focus of mercury pollution is determined by the average daily concentration of mercury vapor in the inhaled air and comparing it with the MPC (for atmospheric air, the average daily MPC \u003d 0.0003 mg / m3).

Clinical examination of the population and determination of the mercury content in biospheres (blood, urine, hair) are recommended when the concentration of mercury vapors for the working area is within 0.01-0.02 mg / m3, and for atmospheric air - about 0.003-0.005 mg / m3 with the duration of such exposure for several weeks or months. At lower concentrations or shorter exposure, clinical examination of pregnant women, as well as children (in case of parental referral) can be limited.

Premises are considered contaminated if the content of mercury vapor in the air exceeds the established hygienic standards (MPC for the air of residential premises, schools, preschool institutions and public buildings - 0.0003mg / m3). Contaminated premises are subject to demercurization, that is, a set of measures to remove mercury by various methods: mechanical (collection, sorption, wet mechanical cleaning, removal of contaminated structures, etc.), physical (calcination, forced ventilation with hot air), chemical (conversion of mercury into bound state to reduce evaporation rate).

Andrey PODLESNY, Associate Professor,

Victor ANIKEENKO, senior lecturer.

Department of Disaster Medicine and Civil Defense Medical Service, Russian State Medical University.

Vladimir KIRYANOV, Deputy Head of the Department of Toxicology and Medical Protection.

Moscow Medical Academy. THEM. Sechenov.