Chemical weapons are derived from natural or artificial chemicals that are not from living creatures. Any chemical that is dangerous to humans can be considered to be a chemical weapon.

Lethal chemical weapons believed to be possessed by Iraq:

NAME	RATE OF ACTION
Sarin	Minutes
Tabun	Minutes
VX More details on VX	Seconds

Symptoms for the Sarin, Tabun and VX are the same: Skin contact or inhalation leads to disruption of the nervous system, leading to convulsions, paralysis and death.

Countries that U.S. intelligence sources say are making chemical weapons:
Ethiopia
India
Myanmar (Burma)
Pakistan
S. Korea
Vietnam
China
Egypt
Iran
Iraq
Israel
Libya
N. Korea
Syria
Taiwan