Acute hydrogen sulfide poisoning

Introduction to acute hydrogen sulfide poisoning Hydrogen sulfide (hydrogensulfide) is a colorless gas with irritating and asphyxiating properties. The low concentration exposure only has local irritation of the respiratory tract and the eye. At high concentration, the systemic effect is obvious, which is characterized by central nervous system symptoms and asphyxia, hydrogen sulfide. It has a "smelly egg-like" odor, but very high concentrations quickly cause olfactory fatigue without feeling its taste. Mining, smelting, sugar beet making, carbon disulfide, organophosphorus pesticides, as well as leather, sulphur dyes, pigments, animal glue and other industries have hydrogen sulfide production; organic waste sites such as marshes, gullies, septic tanks, sewage sedimentation A large amount of hydrogen sulfide can escape during operation in the pool, etc. It is not uncommon for workers to be poisoned. basic knowledge Proportion of disease: more common in laboratory workers and workers exposed to hydrogen sulfide in the chemical manufacturing industry, the incidence rate is about 0.008%-0.009% Susceptible people: no specific population Mode of infection: non-infectious Complications: coma optic nerve head edema and optic disc edema pulmonary edema

Causes of acute hydrogen sulfide poisoning

Hydrogen sulfide enters the body through the respiratory tract, dissolves quickly in contact with the water in the respiratory tract, and combines with sodium ions to form sodium sulfide, which has a strong stimulating effect on the eye and respiratory mucosa. Hydrogen sulfide absorption mainly affects cytochrome oxidation in the respiratory chain. Enzymes and disulfide bonds (-SS-) act to affect the cell oxidation process, causing tissue hypoxia. When inhaled at very high concentrations, it strongly stimulates the carotid sinus, causing respiratory arrest reflexively; it can also directly paralyze the respiratory center and immediately Causes suffocation and produces "electric shock" death.

Acute hydrogen sulfide poisoning prevention

The employer shall take the following measures in advance when it is required to enter equipment, containers or narrow closed spaces where hazard of hydrogen sulfide is present:

1. Maintain good ventilation in the workplace to ensure that the concentration of hydrogen sulfide in the workplace air meets the national occupational exposure limit requirements;

2. When there is a high concentration of hydrogen sulfide gas in the air, workers should be equipped with an isolated gas mask (such as air or oxygen breathing apparatus);

3. Set up on-site guardians and on-site rescue equipment.

Special precautions should also be taken for production operations that may be exposed to hydrogen sulphide, such as:

1. When working in sewers, septic tanks, bottoms, sludge pools, etc., workers should wear qualified gas masks, body belts, ambulance belts, communication alarms, and others outside the danger zone. On-site ventilation and life-saving equipment, before the operation, prevention and first-aid training and pre-job physical examination;

2. The hydrogen sulfide gas produced by the sulphur dye industry should have a closed reactor and a mechanical exhaust system. The exhaust gas can be neutralized and absorbed by the lye. Hydrogen sulfide and sulfur-containing industrial wastewater must be cleaned before discharge.

3. According to the various industries and the production nature and characteristics of each enterprise, the corresponding prevention and control measures are formulated (see the example of precautionary measures for pre-controlling Hazardous Hazardous Hazard Accidents listed below).

Acute hydrogen sulfide poisoning complications Complications coma optic nerve head edema and optic disc edema pulmonary edema

High concentrations of acute poisoning may suddenly occur coma; complications such as dyspnea or cardiac arrest after respiratory arrest may occur, and fundus examination may show optic nerve head edema in some cases, and some cases may be accompanied by pulmonary edema.

Acute hydrogen sulfide poisoning symptoms common symptoms tears nausea fatigue corneal ulcer

According to the concentration and time of inhaled hydrogen sulfide, the clinical manifestations vary in severity. The mild ones are mainly irritating symptoms, such as tearing, tingling, runny nose, burning sensation in the throat, or accompanied by headache, dizziness, fatigue, nausea and other symptoms. Check the visible conjunctival hyperemia, the lungs may have dry rales, can be recovered in a short period of time after dissociation; moderate poisoning, mucous membrane irritation, aggravation, cough, chest tightness, blurred vision, conjunctival edema and corneal ulcer; Symptoms such as headache, dizziness, mild conscious disturbance, dry or wet rales in the lungs, chest X-rays showing enhanced lung texture or flaky shadows; severe poisoning with coma, pulmonary edema, respiratory and circulatory failure, When inhaling a very high concentration (above 1000mg/m3), "lightning type death" may occur, and severe poisoning may leave nerves and mental sequelae.

Examination of acute hydrogen sulfide poisoning

There are currently no specific laboratory tests.

(1) Increased content of hydrogen sulfide or sulfide in the blood can be used as an absorption index, but it is inconsistent with the severity of poisoning, and its half-life is short, so it is necessary to collect blood within a short time after stopping contact.

(2) The content of urinary thiosulfate can be increased, but it can be interfered by factors such as the measurement time and the sulfur content in the diet.

(3) Sulfemoglobin (SHb) in blood cannot be used as a diagnostic index, because hydrogen sulfide does not combine with normal hemoglobin to form thiohemoglobin, which has nothing to do with the mechanism of poisoning; many studies have shown that there is no blood in humans and animals killed by hydrogen sulfide. Significant thiohemoglobin concentration.

Diagnosis and diagnosis of acute hydrogen sulfide poisoning

diagnosis

Diagnosis can be based on medical history, clinical symptoms, and laboratory tests.

Differential diagnosis

The electric shock death at the scene of the accident should be differentiated from other chemicals such as carbon monoxide or cyanide, acute cerebrovascular disease, myocardial infarction, etc., and also need to enter the environment containing high concentrations of methane or nitrogen and other chemicals to cause air hypoxia. The suffocation is differentiated, and other symptoms should be differentiated from similar diseases caused by other causes or trauma caused by falls after coma.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.