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Determination of PCDD/Fs in Environmental
Samples using Accelerated Solvent
Extraction (ASE) and GC-MS/MS
Paul Silcock,
1
David Gardner,
2
John Fardon,
2
Steve Moss
2
and Inge de Dobbeleer
1
1
Thermo Scientific POPs Centre of Excellence, Bremen, Germany
2
National Laboratory Service - Environment Agency, Leeds, United Kingdom
Application Note
10336
Key Words
Dioxins, furans, PCDD, PCDF, environmental, fly ash,
sediments, complex matrix, accelerated solvent extraction,
isotope dilution, pressurized solvent extraction
Introduction
The measurement of PCDD/Fs in the environment is
a widespread activity carried out by many regulatory
agencies globally. The chronic toxicity of these
compounds to humans and wildlife at extremely low
concentrations requires that the techniques used in
determination must be both sensitive and selective enough
to allow high confidence results. This is especially true
when measuring background levels in environmental
matrices, such as soil and sediment or byproducts from
waste incineration processes. Traditionally high
resolution magnetic sector GC-MS (GC-HRMS)
instrumentation has delivered the required analytical
performance and has become the gold standard technique.
In recent years, there has been more interest in GC
triple-quadrupole instrumentation for this purpose,
especially in the area of food safety control.
1,2
For this
area and environmental analysis, it is necessary to deliver
data that performs in the range of HRMS systems, which
requires especially sensitive triple-quadrupole systems.
It is also necessary to incorporate data-processing
software specifically designed to handle the complex
calculations associated with dioxins analysis.
This application note describes the use of the Thermo
Scientific
™
TSQ Quantum
™
XLS Ultra GC-MS/MS as
applied to the analysis of PCDDs/PCDFs in sediments,
soils, bottom, and fly ash (as incineration by-products)
at the levels of interest and the level of agreement with
“gold standard” analysis using GC-HRMS.
During this study, instrumental LOQs using GC-MS/MS
were calculated in the low fg/µL concentration ranges. This,
along with further analytical performance, is discussed
alongside GC-HRMS; especially the degree of agreement
between the techniques in some routine sample batches.
Materials and Methods
Extraction and Cleanup
The standard spiking protocols, extraction, and cleanup
process for all sediment and soil samples were performed
using an ISO17025 accredited in-house variation of EPA
1613B3. For incinerator ash samples, an in-house method
based upon EN 19484 was applied.
For both of these methods, accelerated solvent extraction
was used as the preferred technique for extraction after
initial sample processing. This is routinely used in the
laboratory to reduce solvent consumption, allow for
automation, and to generate efficient sample extractions
within the performance limits required.