Used as an isotopically labeled internal standard in analytical chemistry, particularly in mass spectrometry and gas chromatography, to accurately quantify trace levels of N-nitrosodimethylamine (NDMA) in environmental, pharmaceutical, and food samples. Its deuterated structure allows for clear differentiation from the non-labeled compound, improving measurement precision and reducing matrix interference. Commonly employed in regulatory testing and contamination studies due to its stability and consistent performance in complex sample matrices.