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According to the "Syria's chemical weapons stockpile" article, describe the effects of 3 kinds of chemical weapons.
VX is the most potent; victim is not able to sustain breathing, glands and organs to stop working, vctim to not be able to sustain breathing. Sarin attacks the nervous system, it can cause death within 10 minutes of inhalation. Sulphur mustard burns exposed body parts, not lethal but may cause cancer and serious disfigurement.