Introduction
Polychlorinated dibenzodioxins (PCDD), polychlorinated dibenzofurans (PCDF) and polybrominated diphenyl ethers (PBDE) belong to the class of persistent organic pollutants (POPs). They are one of the major concerns in present environmental discussion. Due to their environmental persistence, their accumulation in the food chain it is of general interest to analyze them with good sensitivity and confidence.
GC-APCI coupled to a high resolution QTOF-MS offers a suitable and sensitive analytical approach for the analysis of these POPs. Here we report a method for Decabromodiphenylether (decaBDE) and 2,3,7,8-Tetrachlorodibenzodioxin (2,3,7,8-T4CDD or TCDD) as they are key substances for their compound classes. PBDEs are among the EU priority substances and decaBDE is most difficult to analyze, because it is less volatile and additionally thermolabile. TCDD is a priority pollutant world-wide and is the most toxic substance of the PCDD/PCDF family.
Methods
- 450-GC with PAL Combi-xt Autoinjector coupled to a GC-APCI II source to an impact II QTOF mass spectrometer (all Bruker Daltonics).
- decaBDE: 15 m Rxi-5Sil MS capillary column (0.25 mm ID, 0.10 μm film thickness; Restek), operated at 0.9 ml/ min constant helium flow and a GC oven temperature program at 50°C – to 330°C (50°C/min) – hold for 7 min, 1 μl splitless injection.
- TCDD: 40 m Rxi-5Sil MS capillary column (0.18 mm ID, 0.18 μm film thickness; Restek), operated at 0.8 ml/min constant helium flow and a GC oven temperature program at 140°C – to 200°C (50°C/min) - 235°C (2.9°C/min) - 267°C (3°C/min) - 310°C (7°C/min) – hold for 10 min,1 μL splitless injection.
- MS Data were acquired from 50 - 1000 m/z with 4 Hz in positive mode. Quantitation was done in fullscan mode and a 1/x weighting applied.
- EIC traces were smoothed (1 cycle Gauss, 0.77 smoothing width).
Figure 1: Comparison of measured & calculated mass spectra of TCDD. Average mass accuracy of the molecular ion isotopic pattern is 0.6 mDa.>> Download as PDF
Newsletters
Receive the latest pathologist news, personalities, education, and career development – weekly to your inbox.
