Analysis of 6- and 7-ring PAH and other non-EPA PAH by atmospheric pressure laser ionization – mass spectrometry (APLI-MS) in environmental certified reference materials NIST 1941b, NIST 1649b, BAM CC013a and IRMM BCR 535

Abstract

Proceedings in environmental analytical chemistry of polycyclic aromatic hydrocarbons (PAH) in the past decades cover improvements in laboratory methods as well as new insights in the toxicology of single PAH compounds. A re-evaluation of the established list of 16 priority PAH published by the U. S. Environmental Protection Agency seems overdue. In this study we have applied PAH analysis by atmospheric pressure laser ionization – mass spectrometry (APLI-MS) to NIST 1941b, NIST 1649b, BAM CC013a and IRMM BCR 535 giving further references in addition to the certificates of analysis. Gas chromatography enables to distinguish between different alkylated PAH derivatives whereas liquid chromatography additionally allows detection of PAH tentatively with six or more aromatic rings on the level of chemical formula. For an optimal isomer-specific differentiation, LC-APLI-MS should be used in combination with fluorescence detection. Distribution patterns of 6 and 7-ring PAH are presented for urban dust, marine and harbor sediments and the soil sample. Additionally, a set of 14 nitrogen, sulfur and oxygen-containing polycyclic aromatic compounds were analyzed by APLI and quantified in all reference materials for the first time.