Abstract:

A rapid, sensitive and accurate method has been developed for the determination of
seventeen 2,3,7,8-substituted congeners of polychlorinated dibenzo-p-dioxins and dibenzo-furans
(PCDD/Fs) in sediment using isotope dilution high resolution gas chromatography/high resolution mass
spectrometry (HRGC/HRMS). Dibenzo-p-dioxins and dibenzo-furans were extracted from samples by
accelerated solvent extraction (ASE) and then purified by fluid management systems (FMS) with silica
column, alumina column and carbon column. Confirmation and quantitative analysis at pg/g level of
PCDD/Fs were performed by HRGC/HRMS using voltage selective ion record (VSIR) mode. Recoveries of
fifteen isotopically labeled compound solutions (LCS) and the precision and recovery standards
(PAR) were found to be in the range of 49.8%-85.3% and 93.2%-113.8%, respectively. The detection
limits of the method for both 2,3,7,8-tetrachloro-dibenzo-furan (TCDF) and
2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) were determined to be 0.1 pg/g. This method not only
meets the requirements of international standards, but also shortens analysis time from 2 weeks to 2
days.

Key words: dioxin, fluid management systems (FMS), high resolution gas
chromatography (HRGC), high resolution mass spectrometry (HRMS), sediment , accelerated solvent extraction (ASE)