Comparison of the behavior of 13C- and deuterium-labeled polycyclic aromatic hydrocarbons in analyses by isotope dilution mass spectrometry in combination with pressurized liquid extraction

We examined the differences found in the concentrations of polycyclic aromatic hydrocarbons (PAHs) in sediment samples when determined by isotope dilution mass spectrometry (IDMS) using 13C-labeled PAHs (13C-PAHs) and deuterium-labeled PAHs (PAHs-d) as internal standards. The samples were analyzed by pressurized liquid extraction (PLE) in combination with gas chromatography–mass spectrometry. The observed concentrations with PAHs-d as internal standards were significantly (p < 0.05) lower (1.9–4.3%) than those determined with 13C-PAHs. The most important factor responsible for the high recovery of PAHs-d relative to 13C-PAHs and native PAHs is the higher stability of PAHs-d during the PLE process.