Gas chromatographic determination of synthetic musk compounds in Norwegian air samples

A new method is described for the simultaneous analysis of nitro and polycyclic musks in air samples. Additional considerations are given to the aspects of sample preparation and blank problems. For the first time concentration levels of synthetic mush in selected Norwegian air samples were determined. In a preliminary investigation using ambient air samples prepared for the determination of persistent organic pollutants, musk xylene concentrations were between 8 and 19 pg/m(3). A new sample preparation for the simultaneous analysis of polycyclic and nitro musks is presented. Both GC-electron impact (EI) MS and GC-negative ion chemical ionisation (NICI) MS were compared as detection methods. GC-EI-MS is to be preferred for the determination of synthetic musks since GC-NICI-MS is not sensitive enough for the determination for polycyclic mush. Blank problems occurred which have to be carefully considered during the whole work-up procedure. One indoor air sample was taken in the laboratory where the clean-up of the samples took place to evaluate laboratory air contamination. A concentration for 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclo[g]-2-benzopyrane of 2470 pg/m(3) was found using gas chromatographic separation coupled with mass spectrometric detection in the electron impact mode (GC-low-resolution EI-MS). A set of four ambient air samples taken nearby the institute facilities was analysed for both nitro and polycyclic musks. For polycyclic mush, concentrations up to 130 pg/m(3) (GC-EI-MS) were determined and for musk xylene a concentration maximum in ambient air samples 54 pg/m(3) (low resolution EI-MS) was found. Critical considerations about laboratory contamination, clean-up and analysis of ambient air samples are given. (C) 1999 Elsevier Science B.V. All rights reserved.