Methanol (metthanol, methyl alcohol, carbinol, CH3OH) is also known as wood alcohol or wood spirit (wood alcohol, wood spirit). It is a colorless and transparent liquid, miscible with water, ethanol, copper, ether, ester, halogenated hydrocarbons and benzene. It is one of the main components of industrial alcohol. It is volatile and flammable. Intake of 5-10 ml of methanol can cause poisoning, and 30 ml can be fatal. It is divided into acute poisoning and chronic poisoning. Acute intoxication causes systemic diseases mainly central nervous system, damage to the eyes and metabolic acidosis. Chronic poisoning can cause vision loss, visual field defects, and optic nerve atrophy. The toxic effects of methanol on humans are caused by methanol and its metabolites formaldehyde and formic acid, and are mainly characterized by damage to the central nervous system, eye damage and metabolic acidosis. Methanol itself has a narcotic effect and has a direct toxic effect on nerve cells; formic acid damages the optic papilla and optic nerve, leading to optic papillary edema, destruction of the optic nerve myelin sheath and optic nerve damage; methanol interferes with the metabolism of certain oxidative enzymes in the body, causing the accumulation of lactic acid and other organic acids, and the production of methanol metabolite formic acid, leading to metabolic acidosis. Occupational exposure Mainly seen in methanol manufacturing, transportation and industries that use methanol as raw material and solvent, pharmaceutical industry and daily cosmetics industry. For example, it is used in the manufacture of formaldehyde, methylamine, isobutyrate, halogenated methane, cellulose, photographic film, plastics and fungicides, as a solvent for dyes, resins, rubber and spray paint, as a denaturant for ethanol, and as an antifreeze agent, a pipeline dehydrating agent, a copying fluid, a motor fuel, a furnace fuel and an intermediate for the manufacture of methyl tert-butyl ether.