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Unit 2Chemical Weapons
All chapters
  1. 1. Introduction
  2. 2. The History of Chemical Warfare
  3. 3. Evolution of the Norm against Chemical Weapons
  4. 4. Current Challenges Posed by Chemical Weapons
  5. 5. The EU and Chemical Weapons
  6. 6. Summary and Further Reading
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Picture of gas shells pilled up in a warehouse (public domain https://en.wikipedia.org/wiki/File:155mmMustardGasShells.jpg)

Above: Mustard gas shells, U.S. Army. (public domain, wikipedia.org)

public domain, wikipedia.org

Chemical Weapons

Modern chemical weapons (CW) were first used on a large scale in 1915 and became a prominent feature in the battles of World War I. Chemical weapons were the product of scientific advances, technological developments and industrialisation. The efforts to prohibit their use in war began as early as 1899 but accelerated after the Armistice of 1918. Today, the 1993 Chemical Weapons Convention (CWC) is the strongest ban on CW development, production, stockpiling and use in force. However, since the mid-1990s, new ways of using toxic agents have emerged, including in terrorism, crime and assassination operations. From 2013 on, chemical warfare also returned to the forefront in the Syrian civil war, with CW use attributed to government military forces and the Islamic State in Iraq and the Levant (ISIL). Although all CW declared under the CWC have now been destroyed, the problem of CW has not completely disappeared. New scientific and technological developments challenge the prohibition because they may allow new types of toxic agents, production methods or dissemination methods, in which new categories of actors may acquire an interest. This learning unit introduces you to the history of CW use, the different types of agents, and the efforts to outlaw their manufacture, possession and use under any circumstances. It also discusses the various challenges to the norm against CW and the efforts to strengthen that norm in view of evolving threats and challenges.

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Chapters

  1. 1. Introduction

  2. 2. The History of Chemical Warfare

    Military Objectives of Chemical Warfare

  3. 3. Evolution of the Norm against Chemical Weapons

    From the Hague Peace Conference to the Rome Statute

  4. 4. Current Challenges Posed by Chemical Weapons

    Science, terrorism and the need for international collaboration.

  5. 5. The EU and Chemical Weapons

    The right to live free from the fear of deadly weapons, including chemical ones

  6. 6. Summary and Further Reading

Learning Objectives

Learning objectives

After completing this learning unit, the student will:

  • understand the nature of chemical weapons (CW) and their effects on humans, animals and the environment
  • understand the technical foundations of CW
  • be familiar with the Chemical Weapons Convention (CWC) and other relevant international treaties
  • understand the current nature of the CW challenge, including
    • the evolution of the CW concept
    • dual-use issues relating to civilian research, development and production activities
    • legitimate and illegitimate uses of irritants (e.g. riot control agents)
    • terrorism
    • chemical security and safety
  • have a detailed background on
    • CW use in Syria and the international response to a major violation of the norm against CW
    • CW use in terrorism and assassination operations
    • the opportunistic use of industrial toxic chemicals (ITCs) and commercially available toxic products
  • have an overview of EU policies in support of the CWC and the norm against CW

Credits

  • Jean Pascal Zanders profile image

    Jean Pascal Zanders

    The Trench

    Dr Jean Pascal Zanders (Belgium) is an independent researcher/consultant on disarmament and security questions. He heads The Trench, a research initiative dedicated to the future of disarmament. He is also a non-resident Senior Research Associate at the Fondation pour la Recherche Stratégique (Paris).

    He holds Master’s Degrees in Germanic Philology-Linguistics (1980) and Political Sciences (1992) and a PhD Degree in Political Sciences (1996) from the Free University of Brussels. He was Project Leader of the Chemical and Biological Warfare Project at the Stockholm International Peace Research Institute (1996–2003), Director of the Geneva-based BioWeapons Prevention Project (2003–08) and Senior Research Fellow at the European Union Institute for Security Studies (2008–13).

    He has participated as an expert to the Belgian and EU Delegations in the BTWC and CWC meetings since 2009. From January 2016 until December 2019, he chaired the Advisory Board on Education and Outreach (ABEO) of the Organisation for the Prohibition of Chemical Weapons (OPCW) and remained a member until December 2021.

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Disclosures

Content Warning

This learning unit may contain audio-visual material or texts, which may not be suitable for all audiences.

Funding

This Learning Unit was produced with financial assistance from the European Union. The contents of this Learning Unit are however the sole responsibility of the author(s) and should under no circumstances be regarded as reflecting the position of the European Union.

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Preferred Citation

Jean Pascal Zanders, "Chemical Weapons" in EUNPDC eLearning, ed. Niklas Schörnig, Peace Research Institute Frankfurt. Available at https://eunpdc-elearning.netlify.app/lu-02/, last modified 22 May 2025

Editorial Note

This is a beta version of the learning unit, which is regularly optimised. Please report any factual errors or discrepancies to the publisher. (support(at)nonproliferation-elearning.eu). Please note that although the original text was written by the authors, the video production and simplifications were carried out by PRIF.

The EU Non-Proliferation and Disarmament eLearning Course aims to cover all aspects of the EU non-proliferation and disarmament agenda. It's produced by PRIF with financial assistance of the European Union. The contents of individual learning units are the sole responsibility of the respective authors and don't necessariy reflect the position of the European Union.