Is the chemical hydrogen sulfide harmful to the human body?

Hydrogen sulfide is an important chemical raw material and a colorless acidic gas. It will burn when it encounters an open flame. If there are too many sulfides, it may cause an explosion. So it is considered a very dangerous, flammable and explosive item. You must be especially careful when you come into contact with it. So is hydrogen sulfide harmful to the human body? Let us introduce it below.

Toxicity of hydrogen sulfide

Hydrogen sulfide can directly interfere with the body's oxygen absorption and transport. This causes the respiratory enzymes in the cells to lose their activity, leading to cell death from lack of oxygen and suffocation. Hydrogen sulfide is highly toxic, with an absolute lethal concentration for humans of 1000 mg/m3. When the concentration of hydrogen sulfide in the air is 10-15 ppm, people will show symptoms of poisoning. The maximum allowable concentration in the workplace environment in my country is 10 ppm. (1ppm=1.4mg/m3)

Hydrogen sulfide poisoning mechanism

Hydrogen sulfide poisoning is mainly caused by inhalation through the respiratory tract, but due to long-term low-concentration environment, the skin can also slowly absorb hydrogen sulfide and cause poisoning. Hydrogen sulfide is quickly absorbed in the respiratory tract and digestive tract, and skin absorption is not significant. Part of it is quickly oxidized into non-toxic sulfate or thiosulfate in the blood and excreted in the urine. A portion of the free hydrogen sulfide can be excreted through the lungs without accumulation.

Symptoms of hydrogen sulfide poisoning

1. Strong irritation causes symptoms such as rhinitis and conjunctivitis. 2. Cause suffocation. 3. Classification of hydrogen sulfide poisoning severity: Based on inhalation concentration and time, hydrogen sulfide poisoning can be divided into three levels.

(1) Mild poisoning: caused by long-term exposure to low concentrations of hydrogen sulfide, with an inhalation concentration of 70 to 140 mg/m3 for 1 to 2 hours. It manifests as obvious irritation symptoms: eye pain, tearing, photophobia, runny nose, cough, chest tightness and pain, nausea, vomiting, headache, difficulty breathing, and even fainting. The patient can be revived by moving to fresh air, and the symptoms will gradually disappear after a few days.

(2) Moderate poisoning: On the basis of mild poisoning, the patient continues to inhale oxygen sulfide or inhale a high concentration of hydrogen sulfide 210-350 mg/m3. In addition to the obvious symptoms mentioned above, the patient also has chemical pneumonia and pulmonary edema. The patient will quickly become confused and fall into a coma, with a pale face, cold and clammy skin, dilated pupils, and a rapid and weak pulse. If rescued in time, the coma can be recovered, but after waking up, there will be symptoms such as headache, dizziness, fatigue, nausea, and loss of appetite. It cannot disappear in a short period of time, and patients with complications such as pneumonia and pulmonary edema will take about 2 to 3 weeks to recover.

(3) Severe poisoning: After inhaling high concentrations of hydrogen sulfide, the person will faint on the ground within tens of seconds. Sometimes, one or two breaths of hydrogen sulfide will cause coma, just like electric shock. The person will have muscle spasms all over the body and incontinence. His life is in danger at any time. Even if he escapes from danger, he will still have serious sequelae.

The question of whether hydrogen sulfide is harmful to the human body has been clearly explained above. Now that we know the harm of hydrogen sulfide to the human body, we must pay special attention and be careful when coming into contact with hydrogen sulfide in future work and life. Try to avoid contact with hydrogen sulfide to ensure your health to the greatest extent possible.