Health Effects Research on Dimethyl Sulfoxide (DMSO) Munition Recrystallization Process Solvent. Phase 2

Abstract : In Phase I, the recrystallization process solvent DMSO was found to be mutagenic. In Phase II, several genotoxic tests were used to confirm the mutagenic potential. Attempts to identify the mutagen (s) were not successful. The solvent test substance was already several years old when received. The mutagenic activity, measured in the Ames test, continually declined. The solvent was fractionated and an active fraction was obtained. The active fraction did not contain any of the primary munitions. An attempt at thigh resolution mass spectrometry was performed but the active agent (s) could not be identified. A surrogate munitions mixture was prepared using reagent grade DMSO. This mixture was tested int he Ames Assay and was not found to be mutagenic. The mutagenic activity was either a process contaminant, munition breakdown product or an artifact added during the early storage history of the sample. Keywords: DMSO; AMES Mutagenicity; RDX; TAX; HMX; SEX; RA3; Mouse lymphoma; Sister chromatid exchange; HPLC; Mass spectroscopy; Dimethyl sulfoxide.