International Chemical Weapons Convention (CWC)

 CWC is an arms control treaty that outlaws the production, stockpiling, and use of chemical weapons and their precursors.

 It is administered by the Organisation for the Prohibition of Chemical Weapons (OPCW), an intergovernmental organization based in The Hague, Netherlands.

 Any chemical used for warfare is considered a chemical weapon by the Convention.

 The parties' main obligation under the convention is to effect this prohibition, as well as the destruction of all current chemical weapons.

 192 states have given their consent to be bound by the CWC.

 Israel has signed but not ratified the agreement, while three other UN member states (Egypt, North Korea and South Sudan) have neither signed nor acceded to the treaty.

 Most recently, Angola deposited its instrument of accession to the CWC.

 The convention has provisions for systematic evaluation of chemical production facilities, as well as for investigations of allegations of use and production of chemical weapons based on intelligence of other state parties.

 Some chemicals which have been used extensively in warfare but have numerous large-scale industrial uses such as phosgene are highly regulated, however certain notable exceptions exist.

 Chlorine gas is highly toxic, but being widely used for peaceful purposes, is not officially listed as a chemical weapon.

 Certain state-powers (eg. the Assad regime of Syria) continue to regularly manufacture and implement such chemicals in combat ammunitions.

 Although these chemicals are not specifically listed as controlled by the CWC, the use of any toxic chemical as a weapon is in-and-of itself forbidden by the treaty.

 Other chemicals, such as white phosphorous, are highly toxic but are legal under the CWC when they are used by military forces for reasons other than their toxicity.

Chemicals have few or no uses outside chemical weapons may be produced or used for research, medical, pharmaceutical or chemical weapon defence testing purposes but production above 100 grams per year must be declared to the OPCW.

 A country is limited to possessing a maximum of 1 tonne of these materials.

 Examples are sulfur mustard and nerve agents.

 Chemicals which have legitimate small-scale applications can be manufactured must be declared and there are restrictions on export to countries that are not CWC signatories.

 An example is thiodiglycol which can be used in the manufacture of mustard agents, but is also used as a solvent in inks.