Used as a stable isotope-labeled internal standard in mass spectrometry and gas chromatography for the accurate quantification of ethyl acetate and related esters in complex mixtures. Its deuterated structure allows clear differentiation from non-labeled compounds, improving detection sensitivity and analytical precision. Commonly applied in environmental testing, forensic analysis, and pharmaceutical quality control where reliable measurement of trace esters is required. Also employed in metabolic studies to track ester hydrolysis and reaction pathways without introducing chemical interference.