What is the antidote for hydrofluoric acid?

Hydrofluoric acid (HF) is a dangerous inorganic acid widely used in chemical, electronic manufacturing, glass etching, smelting, cleaning and other industrial fields. It can enter the human body through the skin, mucous membranes, digestive tract and respiratory tract. It is not only severely corrosive to local tissues, but also systemic toxic. In particular, it causes bone decalcification, corrosion and dissolution. How to first aid for hydrofluoric acid burns? What is the antidote for hydrofluoric acid?

Chemical properties of hydrofluoric acid

Hydrofluoric Acid is an aqueous solution of hydrogen fluoride gas, a clear, colorless, fuming corrosive liquid with a strong irritating odor. Hydrofluoric acid is a weak acid with extremely strong corrosiveness. It can strongly corrode metals, glass and silicon-containing objects. Inhalation of vapor or contact with skin can cause difficult-to-heal burns. Laboratories generally use fluorite (the main component is calcium fluoride) and concentrated sulfuric acid to make it. It needs to be sealed in a plastic bottle and stored in a cool place.

Pathogenic mechanism of hydrofluoric acid

Hydrogen fluoride is irritating and corrosive to clothing, skin, eyes, respiratory tract, and digestive tract mucosa. Fluoride ions can enter the blood or tissues and combine with calcium and magnesium ions to make them insoluble or slightly soluble calcium fluoride and magnesium fluoride. If the amount is large, it will directly block blood vessels, directly or indirectly affect the functions of the central nervous system and cardiovascular system, and lead to hypocalcemia and hypomagnesemia syndrome.

Fluoride ions can also combine with hemoglobin to form fluorohemoglobin, inhibit succinate dehydrogenase, cause oxygenation to decrease, and affect cellular respiratory function. Inhalation of high-concentration steam or percutaneous absorption can cause pneumocystis pulmonary edema.

In addition, hydrofluoric acid can cause obvious burns at the contact site, dehydrate and dissolve tissue proteins, quickly penetrate the stratum corneum, penetrate deep tissues, dissolve cell membranes, and cause tissue liquefaction. In severe cases, it can reach the periosteum and bone, turning bones into calcium fluoride, forming ulcers that heal slowly.

Antidote for hydrofluoric acid

The principle of antidote for hydrofluoric acid is to use some soluble calcium and magnesium salt preparations to combine with fluoride ions to form insoluble calcium fluoride or magnesium fluoride, thereby inactivating fluoride ions.

-Immediately rinse the skin with hexafluorine or a large amount of running water for a long time after contact, dilute and flush the hydrofluoric acid as soon as possible. This is the most effective measure and the key to treatment

-Soak or wet compress with lime water on site

-Soak or wet compress with 20mL of 5% calcium chloride, 20mL of 2% lidocaine, and 5mg of dexamethasone

-Soak with saturated glacial magnesium sulfate solution

-Apply calcium gluconate gel

The above antidote for hydrofluoric acid is only for temporary use in emergency situations, and the injured need to go to the hospital for treatment in time.