Method Statement Dioxins (PCDD/Fs)
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Revised on 01/24/08
Contents
Introduction
Principle
Performance
Characteristics
Range
of Application
Limit of
Detection
Analytical
Quality Control
References
Introduction
The performance of this method is validated in accordance with
internationally recognised procedures.
This document describes the procedures followed in the analysis of
environmental, biological and industrial matrices for PCDD/F content.
The concentration range covered by the method will depend on mass
spectrometer sensitivity, sample size, internal standard recoveries
and final extract volume but the GC/MS linear range should lie
between 0.1 pg and 5 ng injected. Note that the lower limit of
linearity is dependent on attainment of the necessary GC/MS response.
The GC/MS response is also congener dependent to a small degree,
generally decreasing with increasing degree of chlorination. For
example, the GC/MS detection limit for
1,2,3,4,7,8,9-heptachlorodibenzofuran (1,2,3,4,7,8,9-HpCDF) is
approximately four times greater than that of
2,3,7,8-tetrachlorodibenzo- p -dioxin (2,3,7,8-TCDD).
Principle
The method involves Soxhlet, liquid-liquid or other specific
extraction of the test sample, followed by removal of chemical
interferences using open column chromatography and concentration
prior to capillary gas chromatography coupled with high-resolution
mass spectrometry. Quantitation is via the isotope dilution/internal
standard technique, relative to isotopically labelled PCDD/F internal
standards added to the test sample prior to extraction.
Soil samples
0.1 to 10 g aliquots of samples are spiked with labelled internal
standards then extracted by Soxhlet with 300 ml of toluene for a
minimum of 16 hours.
Water samples
200ml to 1l aliquots of the shaken sample are taken then spiked
with labelled internal standards and then extracted by liquid/liquid
techniques with dichloromethane.
Ambient air/stack emission samples
The XAD resin (or PUF plug) and/or the filter are directly
introduced into a Soxhlet thimble spiked with labelled internal
standards then extracted with 300 ml of toluene for a minimum of 16
hours.
"Combination/Florisil Column" Purification
Each extract is then concentrated to incipient dryness and passed
through a “Combination Column” containing layers of base,
acid and neutral silica gel. The purified extracts are then passed
through a fractionating florisil column. The dioxin fraction is then
concentrated, fortified with labelled recovery standards and run by
HR GC/MS.
Performance
Characteristics
Substances Determined
This method is suitable for the analysis of the 17 toxic PCDD/F
congeners, and/or 'total' of the non-toxic ones.
Range of Application
Soils 0.2 ng/kg to 10 ug/kg
(compound dependent)
Waters 0.004 ng/l to 0.2 ug/l
(compound dependent)
Ambient air/stack 2 pg to 100 ng
(compound dependent)
Limit of Detection
Analytical Quality
Control
Analytical quality control is maintained by a number of measures:
Multi-point calibration with
authentic standards (with defined minimum performance
characteristics)
GC Performance Checks Prior to
each analytical batch
Analysis of reagent/method blanks
within each analytical batch
Participation in external
proficiency testing and interlaboratory schemes such as FAPAS
References
Method 23A:
Determination of Polychlorinated Dibenzo-p-Dioxins (PCDDs) and
Polychlorinated Dibenzofurans (PCDFs) from Stationary Sources",
US EPA, Revision 1, December 1996.
Method 1613: "Tetra- through Octa- Chlorinated Dioxins
and Furans by Isotope Dilution HRGC/HRMS, Revision B", pubd.
United States Environmental Protection Agency Office of Water
Regulations and Standards, Industrial Technology Division, Office of
Water, October 1994.
Ambridge, P.F. et al , "Acceptance Criteria for
analytical data on polychlorinated dibenzo- p -dioxins and
polychlorinated dibenzofurans", Chemosphere , 21 (8):
999-1006, (1990).
COMMISSION DIRECTIVE 2002/69/EC. of 26 July 2002, laying down
the sampling methods and the methods of analysis for the official
control of dioxins and the determination of dioxin-like PCBs in
foodstuffs
COMMISSION DIRECTIVE 2006/13/EC of 3 February 06 establishing
requirements for the determination of levels of dioxins and
dioxin-like PCBs in feedingstuffs
BS/ISO 18073:2004 Water quality - Determination of tetra to
octa-chlorinated dioxins and furans - Method using isotope dilution
HRGC/HRMS
FOOD SAMPLES CLEAN-UP USING SEMIPERMEABLE POLYETHYLENE
MEMBRANES (SPM) FOR THE DETERMINATION OF POLYBROMINATED DIPHENYL
ETHERS, Adam Jan Grochowalski, Dominika Wojtalewicz, presented at
Dioxin 2005, Toronto, August 2005.
BS/EN 1948:2006-1,2 and 3, 2006. 'Stationary source
emissions-Determination of the mass concentration of PCDDs/PCDFs'.
SALLY quantitation program reference manual.
VG OPUS operating and reference manuals.
SAL Organic SOP 3 "Preparation of Stack Sampling Media".
Method Implementation Document
(MID 1948), "BS EN 1948 Parts 1-3: 2005, Stationary source
emissions - Determination of the mass concentration of PCDDs/PCDFs
and dioxin-like PCBs. Part 1: Sampling of PCDDs/PCDFs, Part 2:
Extraction and clean-up of PCDDs/PCDFs, Part 3: Identification and
quantification of PCDDs/PCDFs" Environment Agency, May 2006
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