Bruce worked first on gas and liquid chromatographic measurements of polycyclic aromatic hydrocarbons (PAHs) in a number of natural matrix materials, including Standard Reference Materials (SRMs). He also researched supercritical fluid extraction (SFE) in both off-line and on-line applications, contributing to a more realistic view on the effectiveness of this extraction technique in environmental applications. As part of a continuing other agency project, Bruce has worked on refining techniques for gleaning both qualitative and semi-quantitative organic chemical information from very small samples (≤ μg). Most of his experience is in gas chromatography with mass spectrometric detection (GC/MS) in both electron impact ionization (EI) and chemical ionization (CI) modes, and he has used GC/MS in the certification of a number of SRMs. Bruce has developed and refined GC/MS methods for the measurement of explosives, fatty acids, metabolites, and plasticizers in a variety of samples and SRMs and is the technical contact for a large variety of SRMs from air particulate matter to frozen human serum.