291 / 302
Consolidated GC-MS/MS Analysis of OCPs,
PAHs, and PCBs in Environmental Samples
Inge de Dobbeleer, Joachim Gummersbach, Hans-Joachim Huebschmann, Anton Mayer, Paul Silcock
Thermo Fisher Scientific, Dreieich, Germany
Application Note
52389
Key Words
Organochlorine pesticides, polychlorinated biphenyls, polyaromatic
hydrocarbons, soil samples, water samples, building material, repeatability,
linearity
Goal
To describe the analysis of semivolatile compounds in various environmental
matrices, showing the productivity and high quality results of the GC-MS/
MS system.
Introduction
Organochlorine pesticides (OCP), polyaromatic
hydrocarbons (PAH), and polychlorinated biphenyls
(PCB) are compound classes that are highly familiar to
routine environmental or contract testing laboratories.
Various approaches are taken to address these compound
classes in the diverse matrix environment experienced by
these laboratories.
Gas chromatography-mass spectrometry (GC-MS) is well
suited for the analysis of OCPs, PAHs, and PCBs. Single
quadrupole GC-MS has offered the opportunity for the
environmental laboratory to increase selectivity for these
analytes over that of classical detectors, such as UV and
fluorescence detectors in HPLC and ECD and FID
detectors in GC. This has allowed for limited optimization
of sample preparation procedures to increase time to
result and ultimately reduce laboratory costs.
Triple quadrupole GC-MS/MS provides a significant
increase in selectivity when compared to single quadrupole
GC-MS. This selectivity has a profound effect on the
ability to cut through chemical background (interference),
which enhances the capability and productivity of an
environmental testing laboratory. This technique is being
increasingly utilized by many environmental laboratories,
especially those looking for a competitive edge.
Unfortunately, for laboratories newer to GC-MS/MS, the
adoption of this technique presents a challenge in realizing
the productivity advantages offered without significantly
impacting continued laboratory operations.
1,2
This application note describes a high performance, highly
productive analysis of OCPs, PAHs and PCBs in
environmental samples through a consolidated GC-MS/MS
method using the Thermo Scientific
™
TRACE
™
1310 GC
and the TSQ
™
8000 triple quadrupole GC-MS/MS. Also
described is the use of smart software tools that are
integrated into the method development and analysis
workflow to minimize the time needed to implement
and maintain the methodology in routine.
Experimental Conditions
Sample Preparation
Water samples
To 1 L of sample, n-hexane was added and the mixture
was shaken. After the separation of water and organic
phases, the organic phase was removed and dried with
anhydrous Na
2
SO
4
. An aliquot of the organic extract was
evaporated to a volume of 3–4 mL and then evaporated
under a gentle nitrogen stream to the final volume.
Solid samples
Into a glass jar, 10 g of the sample (soil, sediment, or
building material) was weighed, then anhydrous Na
2
SO
4
and 40 mL of extraction solvent mixture (hexane and
acetone) were added. The glass jar was sealed with a
Teflon
®
seal and sonicated for 20 min. An aliquot of the
sample extract was placed into a Kuderna – Danish
apparatus, and another 40 mL of extraction solvent
mixture was added to the sample and the extraction was
repeated. An aliquot of second extraction was added to
the first extraction aliquot. The extract was evaporated to
a volume of 3–4 mL and then evaporated under a gentle
nitrogen stream to the final volume.