The Science of the Chemical Weapons Convention.

Operational implementation of the Convention requires that inspectors and those tasked with verification, monitoring, and capacity building (training) activities are equipped with foundational technical knowledge and the specialized capabilities and equipment required to recognize characteristics of toxic chemicals and the signs and signatures of their presence and exposures, understand chemical manufacturing processes and what the process equipment and work flow indicates about the nature of the chemicals being produced, neutralize and destroy chemical agents, and perform and interpret chemical analysis. This requires knowledge and skill sets that go beyond the science of chemistry and includes the ability to infer information from purely observational assessments such as identifying a type or class of toxic chemical from the presentation of a toxidrome in an exposed human or animal.

Given the potential for OPCW staff (inspectors and others) to be called upon to deploy at short notice when there are allegations of chemical weapons use and/or a State Party requests assistance, a variety of other specialized technical skills and knowledge are also needed. They encompass protective measures for chemical exposures, medical response, investigative and forensic science, and other skills that may go beyond the boundaries of scientific and/or engineering-based disciplines. Scientific concepts underpin the definitions of what constitutes a chemical weapon and provide a basis for operationalizing treaty obligations. The scientific basis of the Convention, however, is not purely chemistry. For example, the definition of a toxic chemical (the fundamental concept that defines a chemical weapon), from Article II, paragraph 2: Any chemical which through its chemical action on life processes can cause death, temporary incapacitation or permanent harm to humans or animals. This includes all such chemicals, regardless of their origin or of their method of production, and regardless of whether they are produced in facilities, in munitions or elsewhere. (For the purpose of implementing this Convention, toxic chemicals which have been identified for the application of verification measures are listed in Schedules contained in the Annex on Chemicals.) “Chemical action on life processes” better describes molecular biology than the science of chemistry, and it also must be appreciated that the definitions in the text of the Convention may not be purely technical. For example, the definition of a chemical weapon, from Article II, paragraph 1:“Chemical Weapons” means the following, together or separately: 1. Toxic chemicals and their precursors, except where intended for purposes not prohibited under this Convention, as long as the types and quantities are consistent with such purposes; 2. Munitions and devices, specifically designed to cause death or other harm through the toxic properties of those toxic chemicals specified in subparagraph (a), which would be released as a result of the employment of such munitions and devices; 3. Any equipment specifically designed for use directly in connection with the employment of munitions and devices specified in subparagraph (b). The inclusion of the words “except where intended for purposes not prohibited” brings a component of intent to the definition, requiring an understanding of context for the presence and production of a “toxic” chemical before it can be determined to be a weapon; further complicating this, is that all chemicals have “a lethal dose”, where even for exposures to chemicals we think of as benign, toxic effects can be induced at high enough exposure concentrations. Additionally, parts (b) and (c) of this definition describe components of weapons required to deploy and disseminate toxic chemicals but are not themselves toxic chemicals. Molecular biology and chemistry are foundational scientific disciplines in these definitions, yet production and use of chemical weapons, like any technology or “system”, requires knowledge, skills and components that transcend disciplinary boundaries. The science of chemistry is important to understand, but it is the realm of chemical engineering that is required for large-scale production and scale-up of chemical processes, materials science supports the design of advanced protective equipment, atmospheric and environmental sciences provide capabilities to understand the dynamics and fate of chemical agents released into the environment in an attack scenario, knowledge from life science and medical fields is needed to understand the toxicology of agent exposure and medical response for chemical injury (and for developing effective medical countermeasures), physics and engineering inform the development of delivery systems and devices, and there are further dimensions that come from a diversity of other disciplines. To be in the best position to counter and respond to chemical weapons, it is useful to think of a chemical weapon as a system of components, that includes chemicals, chemical synthesis processes, chemical delivery methods, and more. How these components look and fit together provides a more informed approach to understanding and countering chemical weapons, helping to identify the capabilities and knowledge needed for science and technology in such efforts. Complicating this, however, is the context and intent by which chemicals are being used, which ultimately defines what is a chemical weapon independent of the science and technology found in its components. As an example of a system perspective, concerns have been raised around microscale synthesis capabilities as a means to hide the footprint of a equipment may certainly allow for small space requirements, if more than microscale amounts of material are produced, operationalization would still require bulk amounts of precursor chemicals and output chemical products (which, if toxic agents, may require special storage and containment considerations, and there may also be associated waste streams). Additionally, using automated flow reaction systems has different energy and resource requirements than a traditional laboratory might have (and especially a low-tech clandestine laboratory). If only small quantities of chemical are intended to be produced (especially if on sub-gram scales), the footprint of traditional glassware in a laboratory is also quite small (and when considering the equipment, pumps, reagent bottles, etc. required to run a flow chemistry system, may take up similar workspace area in a laboratory). Understanding how such technologies integrate with the infrastructure in which they are used adds to the types of signatures and observations that help to place such chemical activities in context. Since the Convention entered into force in 1997, the world has seen unprecedented levels of scientific and technological change, bringing forward innovations and capabilities often unanticipated at the time of treaty negotiations. Technological change has continued to forge ahead at an increasingly rapid pace, accompanied by an internet-enabled expansive diffusion and globalization of scientific knowledge and information (consider that in 1997, only 2% of the world population had internet access, in 2024, this stands at 67%). The large-scale diffusion of knowledge provides for the exchange of ideas by those interested in engaging, and with it a wealth of information and ideas become available for others to watch, “borrow”, and combine with anonymity. From a security perspective, technological change will always raise concerns of potentially malicious application, yet more visibility from an engaged community might also allow for signs of such use to be recognized. Both outcomes are possible, yet how likely one or the other would be is subject to great uncertainty. The concerns for malicious use are further complicated by how we talk about science with new terminology and technical jargon and find new ways to use and adopt new technologies, which can blur and challenge the common understandings and definitions that have informed the agreed-upon policies for treaty implementation. Scientific pursuits are driven by curiosity and discovery, while policy is about norms and values - the norms of values of the Convention are focused on banning chemical weapons and preventing their reemergence, while the science of chemistry invents and/or discovers new chemicals, millions of them, every year, and has always been seen as an innovative and future-shaping scientific discipline. The drafters of the Convention understood that scientific and technological change is inevitable. Given the afore-mentioned considerations, it should come as no surprise that in mandating States Parties to review and keep abreast of scientific developments relevant to treaty implementation in Article VIII, the Convention does not specify which scientific disciplines should be reviewed (not even chemistry itself). Nor should it, because the Convention is not intended to define boundaries of scientific fields or dictate what is or what is not “chemistry” or any other technical discipline for that matter. Rather, the purpose is to ban and eliminate chemical weapons, drawing upon relevant scientific and technical knowledge and capabilities to achieve success. Monitoring, understanding the context, and predicting the potential impact of scientific and technological change on treaty implementation will always present challenges. New and disruptive technologies often develop through trans-disciplinary processes, demanding the systems perspective previously mentioned and requiring those undertaking these tasks look across developments and trends in scientific and engineering fields and beyond, not chemistry alone. The science and technology needed to develop, defend against, andrespond to chemical weapons come at an intersection of technical knowledge and practical needs for truly adopting and using new technologies in reliable and predictable ways; and as will be discussed later in this paper, the most recent examples we have seen of the use of chemical weapons hardly qualifies as new and cutting-edge technology. The amount of information generated every year in scientific fields is vast. In 2022, the estimated annual output of scientific papers reached 3.3 million. In that same year, nearly 3.5 million patent applications were also submitted, and these numbers continue to grow annually. Collaboration and joint publication between institutions is common in science. Of the papers published in 2022, over 20% of them were coauthored by scientists residing in two or more States Parties to the Convention. Once again, context is important in understanding what is being published and produced in scientific literature and reports. For example, during the deliberations that led to the amendments to Schedule 1 of the Convention in June 2020, statements from several peer-reviewed scientific papers and patents (which are legal documents granting ownership of an “invention” rather than a scientific document) were cited to make false allegations about the origins of some of the chemical families being proposed for addition to the Annex on Chemicals; which should serve to remind us that those reviewing the scientific literature must also understand it if they are to provide credible advice. There are practical limitations in trying to keep abreast of scientific literature. To fully comprehend the impact and potential of new science requires engagement with those driving and turning scientific advances into real-world applications (which generally requires skill sets and resources that look different than what is seen in a single disciplinefocused research laboratory). For the Convention to remain relevant in the face of technological change, implementation must stay abreast of new developments that could affect its operation and this usefully includes technological change that benefits the Convention. Ultimately, this requires maintaining adequate levels of institutional technical knowledge and expertise, engaging with scientific experts from outside the OPCW, and access to sound scientific advice (where the SAB plays a key role).