RECOMMENDED OPERATION PROCEDURES FOR CWC-RELATED ANALYSIS Section 5. Reporting Chapter III. A review of spiking chemicals used in the first 40 OPCW Proficiency Tests Version 1.0 ROP 5-III Date 11 December 2017 Page 753 Chapter III. A review of spiking chemicals used in the first 40 OPCW Proficiency Tests Authors Keith Norman, Stephen Johnson Cranfield Forensic Institute Cranfield University Defence Academy of the United Kingdom Shrivenham, Swindon SN6 8LA, UK E-mail: kpaknnorman@iinet.net.au, s.johnson@cranfield.ac.uk Reviewers Hugh Gregg Organisation for the Prohibition of Chemical Weapons Johan de Wittlaan 32, 2517 JR, The Hague, The Netherlands E-mail: hugh.gregg@opcw.org Harri Kiljunen Finnish Institute for Verification of the Chemical Weapons Convention (VERIFIN) P.O. Box 55, FI-00014 University of Helsinki, Finland E-mail: harri.kiljunen@helsinki.fi Chua Hoe Chee DSO National Laboratories, 12 Science Park Drive, Singapore 118225 E-mail: choechee@dso.org.sg Peter Siegenthaler Spiez Laboratory, Austrasse,CH-3700 Spiez, Switzerland E-mail: peter.siegenthaler@babs.admin.ch 1. Scope From 1997 until 2016, the Organisation for the Prohibition of Chemical Weapons (OPCW) has coordinated 40 proficiency tests for the analysis and identification of intact chemical warfare agents, precursor chemicals, degradation and reaction products. This chapter reviews the chemicals used to spike the proficiency test samples, identifying those that have been used multiple times and the distribution of chemicals based upon the schedules in the chemical warfare convention (CWC). The aim of this chapter is not to provide an easy route to pass the proficiency tests but rather to illustrate the range of chemicals that should be considered during method development and/or validation for laboratories participating in, or considering participating in the OPCW Proficiency Test regime. 2. Introduction The production and use of chemical agents in warfare is not a new phenomenon but is one that appears to be on the resurgence. Johnson et al 1 commented on the use of sulfur containing smoke in the fourth century BC in the war between Sparta and Athens. Since then