Decoding synthetic pathways of chemical warfare precursors: advanced impurity profiling of methylphosphonothioic dichloride using GC × GC-TOFMS-chemometrics hybrid platforms

= 12) demonstrated 100% prediction accuracy. Notably, traceability was established at impurity levels as low as 0.5%, exceeding the OPCW verification standards. The established impurity database, in combination with the dual-mode chemometric approach, provides a robust framework for identifying chemical warfare-related precursors.