Toxicity Hydrochloric acid and hydrogen chloride gas are highly corrosive substances that may cause severe burns upon contact with any body tissue. The aqueous acid and gas are strong eye irritants and lacrimators. Contact of conc hydrochloric acid or concentrated HCl vapor with the eyes may cause severe injury, resulting in permanent impairment of vision and possible blindness, and skin contact results in severe burns.
Ingestion can cause severe burns of the mouth, throat, and gastrointestinal system and can be fatal.
Inhalation of hydrogen chloride gas can cause severe irritation and injury to the upper respiratory tract and lungs, and exposure to high concentrations may cause death. HCl gas is regarded as having adequate warning properties. Hydrogen chloride has not been found to be carcinogenic or to show reproductive or developmental toxicity in humans. Flammability and Explosibility Noncombustible, but contact with metals may produce highly flammable hydrogen gas. Reactivity and Incompatibility Hydrochloric acid and hydrogen chloride react violently with many metals, with the generation of highly flammable hydrogen gas, which may explode.