The Chemical Weapons Ban: 20 Years of OPCW

The Organisation for the Prohibition of Chemical Weapons (OPCW) marked the 20th anniversary of its formation on April 29, 2017. This article is an overview of the journey of OPCW during the past two decades.

By Nivedita Das Kundu and Ajey Lele

Brief Background

During the First World War, chemical weapons were used to a considerable degree. Four percent of combat deaths are known to have been caused by gas. The German forces launched the first attack using gas on April 22, 1915. Around 150,000 tonnes of gas were used by German and Allied forces during the First World War, which led to around 90,000 deaths.

The most commonly used gas was chlorine or its variants, such as chlorine?“phosgene gas. Artillery shells containing liquid xylyl bromide were fired as a form of tear gas. Mustard gas was used in several conflicts between the First World War and the Sino-Japanese War (1937-1945). During the Second World War, chemical means were also employed in Hitler’s mass exterminations.1

These weapons have subsequently been used on various other occasions by both states and non-state actors in different parts of the world. The Cold War period saw significant development, manufacture, and stockpiling of chemical weapons. During March 1988, Iraqi forces had used mustard gas and nerve agent sarin at the Kurdish town of Halabja in northern Iraq, killing around 5,000 people. Since 2012, the use of chemical weapons has continued in the Syrian theatre.

The Law

The 1925 Geneva Protocol prohibits the use of chemical and biological weapons in war. This protocol is for the “Prohibition of the Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare.” The protocol was signed at a conference in Geneva under the auspices of the League of Nations in 1925, and entered into force in 1928. However, though this protocol prohibits the use of such weapons, it is silent about the production or storage of such weapons.

Unfortunately, in spite of that convention, chemical weapons were still used during the Second World War. This made people realize the need for more comprehensive and stringent mechanism. Post Geneva Protocol, it took nearly seven more decades to formulate a globally accepted treaty mechanism. In 1992-93, a Chemical Weapons Convention (CWC) was drawn up prohibiting the use, production, and storage of these weapons. This convention entered into force in April 1997. CWC negotiations had started in 1980 in the UN Conference on Disarmament, so the process for the negotiation took almost 12 years.

The Treaty

The CWC is a multilateral treaty that bans chemical weapons and requires their destruction within a specified period of time. This treaty is implemented by the Organization for the Prohibition of Chemical Weapons (OPCW), which is headquartered in The Hague, Netherlands. The OPCW receives states parties’ declarations detailing chemical weapons-related activities or materials and relevant industrial activities.2 After receiving declarations, the OPCW inspects and monitors states parties’ facilities activities that are relevant to the convention, to ensure compliance.3

The Convention offers the most extensive and intrusive verification regime of any arms control treaty, extending its coverage to not only governmental but also civilian facilities. The Con­vention also necessitates export controls and reporting requirements on chemicals that can be used as warfare agents and their precursors.4 This convention requires states parties to declare chemical industry facilities that produce or use chemicals of concern to the convention. Also, if the state has declared any stock of chemical weapons in their own custody or control (such states are known as possessor states) then they are required to destroy it completely.

Since the implementation of the treaty is the responsibility of the OPCW, it is also required to ensure that the member states are provided assistance and protection against chemical threats. This organization is also responsible for fostering international cooperation to strengthen implementation of the Convention and promote the peaceful use of chemistry.

Disarmament figures prominently in Alfred Nobel’s will and the Norwegian Nobel Com­mittee has, through numerous prizes, underlined the need to do away with nuclear weapons.5 Appreciating the exemplary work done by OPCW, this committee awarded them the Nobel Peace Prize in 2013, for their extensive efforts to eliminate chemical weapons.

The Present

Over the past twenty years, approximately 93% of chemical weapon stockpiles declared by possessor states have been eliminated under the supervision of the OPCW. In total there are 192 states which are in agreement with this convention. Egypt, Israel, North Korea and South Sudan are outside the convention. Israel has signed the convention but is yet to ratify. A key non-signatory includes North Korea,6 which is suspected of possessing chemical weapons. Today, around 98% of the global population lives under the Convention’s protection. CWC is considered as one of the most successful disarmament mechanisms.

Recently Syria has posed a major challenge to the convention. The state acknowledged the presence of chemical weapons in their stockpiles during 2012, and has used these weapons on multiple occasions. On September 12, 2013, Syria sent a letter to the United Nations Sec­retary General stating that the Assad regime has signed a legislative decree providing the accession of Syria to the Chemical Weapons Conven­tion. Syria also declared that the state would abide by all the obligations of the convention and also ship out its chemical weapons and destroy its production facilities. With the help of an international coalition, Syria’s declared chemical weapons were completely removed from the country by June 2014.7 However, the Syrian challenge remains far from over. One of the major findings of the United Nations-OPCW report submitted to the Security Council during August 20168 is that the Syrian military had dropped chemical weapons on the towns of Talmenes during April 2014 and Sarmin in March 2015.

On April 4, 2017 chemical weapons were found used in an attack that killed more than 70 people in Syria’s northern Idlib province. It appears that sarin gas was used in this attack. The attack is believed to have been perpetrated by the Syrian government. However, President Assad, who is being fully supported by Russia, has strongly denied any involvement of his regime. At present, it is has become difficult to identify which agency is using chemical weapons in the Syrian theatre.

The Journey

The Conference of the States Parties to the CWC is convened every five years. Such review conferences are expected to monitor the progress of the convention and take into account scientific and technological developments relevant to the convention’s mandate. Three such review conferences have been held in 2003, 2008 and 2013.9

To judge the effectiveness of these review conferences it is also important to host individual conferences in the context of the global politico-strategic landscape.10 The climate surrounding international arms control has mostly been under suspicion, particularly during the initial years of the post-Cold War period. Notably, the CWC is the only Weapons of Mass Destruction treaty mechanism which has been adopted in the post-Cold-War period.11 (Nuclear and Biolog­ical Weapon Convention treaty mechanisms came into existence during 1970s.) The CWC came into force before the 9/11 terror attacks. Naturally, the major challenge for the last decade and a half has been to factor in the issues related to the global war on terror, particularly because the convention does not address the issue of terrorism.

All the three CWC review conferences have culminated in the unanimous declaration of commitment by States Parties to the global chemical weapons ban and a comprehensive review of CWC implementation in the preceding five years. This declaration recommended improvements on the Convention’s implementation and effectiveness. By the beginning of the third review conference (March 31, 2013) almost 80% of the total declared global stockpiles of Category 1 chemical weapons had been destroyed. On June 28, 2013, the CWC entered force for Somalia, making it the 189th State Party.12

The first review conference indicated that though technically the treaty mechanism is likely to aid in meeting the core objective of non-proliferation in the long run, it still would be difficult to remove suspicions totally. During this conference, the US representative (the Assistant Secretary of State for Arms Control) had raised a suspicion about a possible covert Iranian CW programme. Obviously, this accusation was completely denied by Iran. Around the time of the first review conference, the US agencies had identified the following states as undertaking “activities inconsistent with the CWC13.

In the case of Russia, the concerns were about its failure to acknowledge research and development on binary chemical weapons (binary chemical weapons use two non-lethal chemicals that combine to form a lethal agent after launching). Incidentally, the US had a similar program from the 1950s until 1992. CWC opponents believed the Russian case was typical, showing the difficulties of verification and the lack of trustworthiness of a state.

Interestingly, during a decade and half none of the above states have shown any inclination to acquire or use such weapons. The threats have instead emerged from states like Libya and North Korea—that is, states which were not party to the CWC.14

All three review conferences held to date indicate that states are trying to strike a balance between national self-interest and ensuring the efficacy of the treaty pact.

One of the major tasks for the OCPW is to ensure that all declared stockpiles of the chemical weapons are destroyed according to the guidelines. The task is to destroy 8.67 million items, including munitions and containers containing in total 72,304 tonnes of extremely toxic chemical agents. As of September 2016, some 90% of the world’s declared stockpile of 72,304 metric tonnes of chemical agent have been verifiably destroyed. Also, 4.97 million, or 57.32% of the 8.67 million chemical munitions and containers covered by the CWC, have been verifiably destroyed.15

The major challenge for the OPCW now is to ensure the complete destruction of the US and Russian stockpiles, as neither state met the previous April 2012 deadline for destroying their chemical weapons.

In 2015, the OPCW extended the deadline for the destruction of toxic agents to 2020. However, it appears that the US is unlikely to meet this deadline and it has claimed that they could finish their job around 2023 (despite claims to have destroyed approximately 90% of their stockpiles). Today, Russia16 claims to have already destroyed over 96% of its chemical weapons stockpiles.

The Future

The Chemical Weapons Convention and the OPCW as its implementing body is responsible for the total elimination of chemical weapons. During last two decades of its journey the OPCW has performed this job with utmost sincerity; getting a Nobel Award is the validation of this effort. However, OPCW has a long way to go and needs to remain vigilant.

The CWC mechanism was born before the 9/11 era. In the 21st century the threat of terrorism and asymmetric conflict has increased substantially. The Syrian case is an eye-opener.

The incomplete destruction of those chemical weapons held by Russia and the US has lingered for many years. Both states have genuine difficulties owing to the volume of their stocks. Also, since their stocks are mostly in form of weaponized munitions, destruction takes longer. However, for the OPCW it is important to keep up the pressure on these states as well.

Nivedita Das Kundu is a research associate and adjunct faculty , York University. Ajey Lele is Senior Research Fellow, Institute for Defence Studies and Analyses, New Delhi.


1 accessed on 6 April 2017




5, accessed on 5th April 2017

6, accessed on 20th April 2017

7, accessed on 3rd April 2017

8 accessed on November April 2016

9, accessed on 6th April 2017

10 accessed on 6th April 2017

11, accessed on 6th april 2017

12 accessed on 15th April 2017

13, accessed on 20th April 2017

14 Alexander Kelle, ‘The CWC After Its First Review Conference: Is the Glass Half Full or Half Empty?”, Disarmament Diplomacy, Issue No. 71, June-July 2003

15 accessed on 5th April, 2017

16 accessed on 5th April 2017

Peace Magazine July-September 2017

Peace Magazine July-September 2017, page 12. Some rights reserved.

Search for other articles by Nivedita Das Kundu here
Search for other articles by Ajay Lele here

Peace Magazine homepage