Used as a stable isotope-labeled internal standard in gas chromatography-mass spectrometry (GC-MS) analyses, particularly for quantifying volatile sulfur compounds in environmental, biological, and food samples. Its deuterated structure allows clear differentiation from non-labeled analogs, improving accuracy in trace-level detection. Commonly applied in studies of atmospheric chemistry, metabolic pathways, and flavor/aroma profiling where precise tracking of sulfur-containing metabolites is required. Also employed in kinetic isotope effect studies and as a tracer in industrial process monitoring.