Environmental PAH analysis by gas chromatography - atmospheric pressure laser ionization - time-of-flight-mass spectrometry (GC-APLI-MS)

Stader C., Beer F.T., Achten C.

Abstract

The application of polycyclic aromatic hydrocarbon(PAH) analysis by gas chromatography coupled withatmospheric pressure laser ionization and mass spectrometry(GC-APLI-MS) to environmental samples was investigatedin the study. The limit of detection for 40 PAH in a standardmixture was 5–100 fg, demonstrating GC-APLI-MS to be ahighly sensitive technique and more sensitive by a factor of100–3,500 compared to GC-MS. Acenaphthylene andcyclopenta[cd]pyrene were not detectable <2,500 fg perinjection. To make use of this very high PAH sensitivity,the technique was applied to samples of environmental interestwith limited available sample amounts such as particulatematter (PM), soot and a sample from a bioaccumulationtest with Lumbriculus variegatus. First, special sample preparationwas necessary and ultrasonic extraction proved to besuitable, if a thorough clean-up was performed and plasticmaterials avoided. By GC-APLI-MS and GC-MS, 224 and28 single PAH compounds were detected in PM, about 1,000and 15 in birch soot, and 9 and 2 in wormtissue, respectively,revealing the enormous potential of the method. The selectivityof GC-APLI-MS was shown for a crude oil where>2,200 PAH were detected without any sample preparation.