Evaluation of a high-resolution gas chromatography/high-resolution mass spectrometry method for the determination of 2,3,7,8-tetrachlorodibenzo-p-dioxin in soil and water.

An analytical protocol for the determination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and total TCDDs in soil, sediment, and aqueous samples using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) was evaluated through replicate analyses of fortified and unspiked soil and aqueous samples. The results of these analyses demonstrated that the method is useful for the determination of 2,3,7,8-TCDD and total TCDDs at concentrations ranging from 10 to 200 pg/g (ppt) in soil samples and from 100 to 2000 pg/l (ppq) in aqueous samples. Absolute recoveries of the method internal standard, (13C12-2,3,7,8-TCDD, ranged from 24 to 88%. Lower levels of detection can be achieved through a slight modification of the method with respect to initial sample size and/or final extract volume. Instrumental parameters that affect data quality, specifically HRGC column performance, mass resolution and mass measurement accuracy are presented.