A number of international frameworks, such as the Chemical Weapons Convention (CWC), the Australia Group (AG), and the Wassenaar Arrangement, contribute to a coordinated multilateral effort to stem the proliferation of chemical weapons (CW). To serve their purpose, these frameworks contain lists of chemicals that can be employed as chemical warfare agents, i.e. the toxic chemicals on which chemical weapons are based, or precursors for their synthesis (hereafter referred to as CW-control lists). Some of these CW-control lists are a compilation of exact structures, where each chemical is individually enumerated. Other lists comprise both exact structures as well as families of chemicals identified by a common scaffold with variable substituents (note 1).

To assist the implementation of CWC mandates, support export controls, and promote chemical security in general, other intergovernmental organizations and individual countries incorporate these CW-control lists in their regulations and national legislation, often integrated with the addition of other chemicals. Moreover, further control lists are crafted by international organizations and national authorities. Some examples are listed below.

In addition to general export control legislation and regulation, several countries have norms that pose additional restrictions on the export of dual-use chemicals to specific countries that pose a particular chemical proliferation risk. For instance, the European Union tightly regulates the export of dual-use chemicals to Syria, within the scope of the restricting measures imposed by Council Regulation (EU) No 36/2012, first issued in 2012 and subsequently subjected to various amendments. Beyond posing additional restrictions on the chemicals already present in the general EU export control lists, this EU regulation comprises additional lists of dual-use chemicals that, although being widely used in chemical industry for non-military purposes, are of concern for their possible role as precursors for the synthesis of chemical warfare agents when exported to Syria.

Curated tabled of CW-control lists

We are manually curating above-mentioned lists for the control of chemical warfare agents and precursors, annotating them with chemical structures (exact structures for individual chemicals and Markush structures for families of chemicals) as well as simplified molecular-input line-entry system (SMILES) notations (Note 2). We are also annotating the tables with information that highlights the overlaps within the various lists, noting for each entry of each list whether that chemical is covered by one or more additional lists, either as an individual chemical or as a member of a family of chemicals. Importantly, to further highlight overlaps and differences between the lists, we also provide a synoptic table in which all the lists are provided side-by-side on one page.

Table 1: CWC Schedules

Table 2: Australia Group “Chemical Weapons Precursors” list

Table 3: Wassenaar Arrangement’s Munitions List 7 (ML7)

Table 4 (Coming soon!): Comprehensive Table of International CW control lists

Table 5 (Coming soon!): Annex V of the WCO Strategic Trade Control Enforcement Implementation Guide

Table 6 (Coming soon!): CW-control portion of the U.S. Munitions List (USML)

Table 7 (Coming soon!): CW-control portion of the U.S. Commerce Control List (CCL)

Table 8 (Coming soon!): CW-control portion of the EU Community Regime for the Control of Exports, Transfer, Brokering and Transit of Dual-use Items

Table 9 (Coming soon!): Syria-specific CW-control list in Council Regulation (EU) No 36/2012

Note 1. It is worth emphasizing that the purpose of these lists is to support efforts to control CW proliferation. None of these lists should be construed as an exhaustive compilation of chemical warfare agents and precursors. Indeed, the CWC includes in its definition of chemical weapons  “any chemical (emphasis added) which through its chemical action on life processes can cause death, temporary incapacitation or permanent harm to humans or animals.” Hence, any weapon designed to bring about death, temporary incapacitation, or permanent harm through the toxic properties of chemicals is to be considered a chemical weapon, and any toxic chemical at the basis of such weapons is to be considered a chemical warfare agent.

Note 2. A document in which the CWC Schedules are annotated with chemical structures and three-dimensional models has been produced by the Organisation for the Prohibition of Chemical Weapons (OPCW): “The Science for Diplomats” Annex on Chemicals – A user friendly and scientifically annotated version of the Chemical Weapons Convention Annex on Chemicals