- Hydrazine (chemical formula N₂H₄) is a highly reactive, volatile, and toxic inorganic compound composed of nitrogen and hydrogen.
- It is a colorless, oily liquid at room temperature, with a pungent, ammonia-like odor, and is miscible with water in all proportions.
- Hydrazine belongs to the family of diimides and structurally resembles ammonia (NH₃), consisting of two amino groups linked by a single nitrogen-nitrogen bond. Due to its strong reducing properties, hydrazine serves as a powerful chemical intermediate and fuel, but also presents serious health and safety hazards.
- In industrial chemistry, hydrazine is primarily used as a reducing agent, corrosion inhibitor, and precursor to blowing agents in polymer production. It is also employed in the synthesis of agrochemicals, pharmaceuticals, and explosives. Perhaps most notably, hydrazine and its derivatives (e.g., unsymmetrical dimethylhydrazine, UDMH) are used as propellants in aerospace applications, especially in satellite thrusters and rocket fuels, due to their high energy density and hypergolic ignition with oxidizers like nitrogen tetroxide. In nuclear power plants and steam systems, hydrazine acts as an oxygen scavenger to prevent corrosion of metal surfaces.
- From a toxicological perspective, hydrazine is highly hazardous. It is flammable, unstable, and carcinogenic, with acute exposure causing symptoms such as nausea, headaches, lung irritation, seizures, and damage to the liver, kidneys, and central nervous system. Chronic exposure, particularly via inhalation or skin contact, is associated with an increased risk of tumor formation in laboratory animals, and it is classified as a probable human carcinogen by the U.S. Environmental Protection Agency (EPA) and the International Agency for Research on Cancer (IARC). Therefore, strict safety measures are required when handling hydrazine in laboratory and industrial settings, including closed systems, protective gear, and adequate ventilation.
- Hydrazine also has significance in biochemistry and toxicology due to its presence in certain natural compounds and drug metabolites. For example, agaritine, found in edible mushrooms of the genus Agaricus, degrades into hydrazine-related byproducts, some of which have shown mutagenic activity. Hydrazine derivatives, such as isoniazid, are used in pharmaceuticals (e.g., to treat tuberculosis), though they require careful dosing due to potential side effects linked to their hydrazine backbone.
