It inhibits the production of cholinesterase in the body, an enzyme that regulates nerve impulses. The effects of nerve agents are highly dependent upon the amount of agent an individual is exposed to. Nerve agents can also be absorbed through the skin, with a percutaneous lethal dosage estimated to be 12,000 mg for Sarin. Initial nerve agent effects are difficulty in breathing, dimming vision, accompanied by pain in the eyes and nose. As symptoms intensify, the victim is subject to nausea, involuntary urination and defecation, and loss of muscle control.
Death occurs by asphyxiation as a result of muscle exhaustion and pulmonary edema.
Depending on the dosage received, death can result within 2-15 minutes. Packages leaking Sarin nerve agent were placed almost simultaneously aboard five subway cars, eventually affecting passengers in sixteen stations. Five days previously, three briefcases had been discovered in a Tokyo subway station. Each case contained three tanks with an unknown liquid, a motorized fan, vent, and battery power source. On March 5, nineteen passengers on the Yokohama subway were hospitalized for eye and respiratory pain from unidentified fumes.