Tips: Hydrogen Cyanide - Lightning Killer! Be careful!

As a kind of suffocating gas, hydrogen cyanide is known as the “lightning killer” and is widely used in organic chemistry, electroplating, mining and metallurgy, paint, dyes, and rubber industries. Most of cyanide is artificially synthesized, but there are also a small amount present in natural substances, such as bitter almonds, barley, peach kernels, cassava and ginkgo. Among them, electroplating, paints, dyes, rubber and other industries have more opportunities for contact.

In the case of hydrogen cyanide acute poisoning, various newspapers are commonly reported:

In 2004, a hydrogen cyanide gas leak occurred in a chemical workshop in Shandong, and 22 people were poisoned.

In 2005, the villagers of Xiaguan Village, Guanyi Township, Chun'an County, Fujian Province, caused poisoning due to hydrogen cyanide poisoning caused by the cleaning of their own abandoned green plums. 22 people were poisoned and 6 died.

In 2009, an electroplating factory worker in Yangzhou accidentally caused a hydrogen cyanide poisoning accident during the cylinder tank cleaning process. One person died and one person was poisoned.

In 2009, a gold mine worker in Shandong experienced an acute hydrogen cyanide poisoning accident during the process of cleaning metallurgical tanks, and 11 people were poisoned.

In 2013, an accident of hydrogen cyanide poisoning occurred during the cleaning of a semi-finished product tank of an acetone-alcohol plant in a factory in a city. Ten people were poisoned and one person died.

In 2015, an acute occupational hydrogen cyanide poisoning accident occurred in a plating shop of a hardware company in Shenzhen, and one person was poisoned.

So today we will come to understand what hydrogen cyanide is. What are the common contact opportunities? What is the toxic mechanism of hydrogen cyanide? What are the clinical manifestations of hydrogen cyanide acute poisoning? How can we prevent it?

What is hydrogen cyanide:

Hydrogen cyanide (HCN), molecular weight 27.03, is a colorless gas with bitter almond taste at room temperature, soluble in water, ethanol and ether. Its aqueous solution is hydrocyanic and hydrocyanic acid belongs to the drama. Toxic substances, which are acidic, react with alkali to form salts, ie cyanide. The cyanides that are generally known are inorganic cyanides, including hydrocyanic acid, potassium cyanide, and sodium cyanide. The organic cyanide is formed by the cyano group being bonded to another carbon atom through a single bond, including acetonitrile and acrylonitrile. Cyanide emits hydrogen cyanide gas at high temperatures or with acidic substances. In cyanide, hydrogen cyanide is the most toxic, and it is a highly active, toxic and fast cytotoxic plasma. The adult lethal dose of hydrogen cyanide gas is approximately 60 mg. Inhalation of hydrogen cyanide in humans reaches 20-40 mg/m3 for several hours. Mild poisoning occurs. After exposure to 150 mg/m3 for 30 minutes, it can die. When the concentration in the air reaches 300 mg/m3. It can suddenly collapse without any aura and "shock-type" deaths occur.

Common contact opportunities:

With the rapid development of China's chemical industry, the application of cyanide has become more and more extensive, and the frequency of use has become higher and higher. The cyanide commonly used in industry includes hydrocyanic acid, potassium cyanide, sodium cyanide, and ammonium cyanide.

Electroplating, mining and metallurgical industry: such as gold plating, copper plating, silver plating, cyanide enriched lead, zinc, gold, silver extraction of precious metals, steel quenching, metal surface carburizing.

Production of cyanide-containing compounds: such as the production of hydrocyanic acid, the manufacture of other cyanide, drugs, synthetic fibers, plastics, rubber, organic glass, paints, etc.

Chemical Industry: Raw materials for the production of various resin monomers such as acrylic resins, methacrylic resins, ethylenediamine, acrylonitrile, and other nitriles.

Fuel industry: synthesis of cyanuric chloride, an active fuel intermediate.

Photographs: Ferricyanide is contained in photographic waste.

Agriculture: such as fumigation insecticides, rodenticides and so on.

Military: Used as a war poison.

Contact with daily life: such as bitter almonds, barley, peach kernels, cassava, and ginkgo all contain cyanide.

Mechanism and clinical manifestations of hydrogen cyanide acute poisoning:

Acute cyanide poisoning is mainly absorbed through sucker channels, and secondly, it can also be absorbed through the skin at high concentrations. Living cyanide poisoning is mainly oral, and the oral mucosa and digestive tract can be fully absorbed. After the hydrogen cyanide enters the human body, it releases the cyanide ion (CN-) and directly binds to the Fe3+ in the cytochrome oxidase, inhibits the activity of the enzyme, causes it to lose the ability to transfer electrons, and blocks the sucking chain, resulting in the loss of oxygen-carrying cells. The ability to occur while "intracellular suffocation." In the case of cyanide poisoning, although the blood is saturated with oxygen, it cannot be used by tissues. The arteriovenous blood oxygen difference is decreased, and the skin and mucous membranes are cherry red.

The clinical manifestations of hydrogen cyanide acute poisoning: (1) Contact reaction: The patient suffers from headache, dizziness, fatigue, chest tightness, and may also be accompanied by irritation symptoms of the eye and the inhalation channel. Most of them are transient and can be compared after disengagement. Fast recovery. (2) Mild poisoning: Mainly manifested as chest tightness, palpitations, accelerated heart rate, headache, and sensation of bitter almond taste, nausea, vomiting, and paradoxical vision. (3) Moderate poisoning: The above symptoms are aggravated, suffocation is rapid, blood pressure is decreased, and the skin is bright red. (4) Severe poisoning: The main manifestations were deep coma, rapid absorption, rapid heart rate, arrhythmia, paroxysmal convulsions, and even severe disturbance of consciousness. Ingestion at high or high doses can produce electroshock death.

Emergency treatment principles:

(1) Immediately leave the scene to the fresh air, quickly implement treatment, and provide oxygen therapy as soon as possible.

(2) Remove contaminated clothing and clean contaminated skin with clean water or 5% sodium thiosulfate.

(3) Ingestion by digestive tract should induce vomiting immediately, and gastric lavage should be performed with 1:5000 potassium permanganate or 5% sodium thiosulfate solution.

(4) The eye contaminants should immediately flush with plenty of clean water or saline.

Precaution:

(1) Reform of the production process to replace toxic raw materials with non-toxic raw materials.

(2) Innovate production equipment and strengthen equipment management and maintenance. Processes that may produce cyanide should be sealed, mechanized, and automated to eliminate running, running, dripping or leaking.

(3) Establish occupational health management system and operating procedures. At the same time, it will formulate accident emergency rescue plans suitable for the company and regularly organize drills to strengthen emergency rescue capabilities.

(4) Enterprises should strengthen personal protection of operators. Workers exposed to cyanide should wear practical protective equipment.

(5) Ventilation and detoxification. Indoor ventilators that are exposed to cyanide should be equipped with mechanical ventilation facilities and should be used for accident ventilation. The number of air changes should not be less than 12 times per hour.

(6) Strengthen the management of limited space operations. The implementation of a limited-space operation permit system strictly enforces occupational hazard prevention regulations for limited-space operations to prevent occupational hazards such as oxygen deprivation and acute poisoning.

(7) Strengthen occupational health education and training. Occupational hygiene training for workers exposed to cyanide to enhance their awareness of the toxic effects of cyanide and their awareness of protection against occupational hazards.