provide the recommended mass spectrometer lock channels for PCDD/PCDFs,
PAHs, and PCBs, respectively. You may use PFK or FC43 as your lock mass
standard. Monitor the quality control check channels specified in these
tables to verify instrument stability during the analysis. Flag data
resulting from failure to maintain lock channel signal during analysis.
    <IP_ADDRESS> The relative standard deviation (RSD) for the mean
response factor from each of the unlabeled analytes and isotopically
labeled compounds used in an analysis must be less than or equal to the
values in Table 23-14 of this method.
    <IP_ADDRESS> The signal-to-noise (S/N) ratio for the MS signal present
in every selected ion current profile must be greater than or equal to
10 in all concentrations of calibration standards for unlabeled targets
and isotopically labeled standards. The ion abundance ratios must be
within the control limits in Table 23-15 of this method.
    10.2.3 Daily Performance Check.
    <IP_ADDRESS> Continuing Calibration Check. Inject a mid-level
calibration standard C4 from Table 23-11, 23-12, or 23-13 of this
method for the compound class being analyzed at least once every 24
hours during an analysis sequence. Calculate the RRF for each compound
and compare each RRF to the corresponding mean RRF obtained during the
initial calibration. The analyzer performance is acceptable if the
measured RRFs for the labeled compounds for a 24-hour period are within
the limits of the values shown in Table 23-14 of this method. The RRF
for each native compound measured in a CCV must not deviate from the
initial calibration by more than the limits shown in this table.
    <IP_ADDRESS> The ion abundance ratios must be within the allowable
control limits shown in Table 23-15 of this method.

    <IP_ADDRESS> Repeat the initial calibration when there is a failure to
meet the requirements for acceptable continuing calibration check
analysis.
    <IP_ADDRESS> Column Separation Check. Use the results from a continuing
calibration check sample to verify and document the resolution required
in Sections 13.3, 13.4, or 13.5 of this method for the compound classes
analyzed with this method.
    <IP_ADDRESS> If you use a confirmation column, perform the resolution
check in Section <IP_ADDRESS> of this method to document the required
resolution on the confirmation column.

11.0 Analysis Procedure

    11.1 Sample Extraction and Concentration. The sample extraction
procedures in this method are the same for PCDD, PCDF, PCB and PAH
targets. Figure 23-4 provides a flow chart showing sample container
combination and extraction steps. Do not allow samples and extracts
destined for PAH or PCB analysis to concentrate to dryness because the
lower molecular weight PAHs and the mono- through tri-chlorobiphenyls
may be totally or partially lost.
    11.1.1 Optional Soxhlet Precleaning. Place an extraction thimble
(see Section <IP_ADDRESS> of this method) and a plug of glass wool into the
Soxhlet apparatus equipped with a Dean-Stark trap, charge the apparatus
with toluene, and reflux for a minimum of 3 hours. Remove the toluene
and discard it. Remove the extraction thimble from the extraction
system and place it in a glass beaker to catch the solvent rinses from
sample transfer to the extraction thimble. Retain the clean glass wool
plug. Alternatively, confirm that the batch blank for reagents,
materials, and media meets the performance requirements in Section 13
of this method.
    11.1.2 Container No. 1 (Filter) Preparation. Spike the filter with
the appropriate pre-extraction filter recovery standard solution(s)
shown in Tables 23-7, 23-8, and 23-9 of this method taking care that
all spike liquid is distributed on the filter. Allow the filter to air
dry, then transfer the filter and the contents of Container No. 1
directly to the glass extraction thimble in the glass solvent rinse
catch beaker so that the filter will be completely immersed in the
solvent during extraction.
    11.1.3 Adsorbent Module. Transfer the adsorbent material to the
glass extraction thimble in the glass solvent rinse catch beaker. Rinse
the module into the thimble in the beaker with the contents of
Container No. 1. Alternatively, suspend the adsorbent module directly
over the extraction thimble in a beaker, then, using a wash bottle
containing methanol, flush the XAD-2 into the thimble onto the filter.
Thoroughly rinse the interior of the glass module that contained the
XAD-2 with toluene.
    11.1.4 Container No. 2 (Acetone and Toluene Rinses). Concentrate
the sample to a volume of no less than 5 mL. Concentrate samples
containing toluene using a heating mantle and three-ball Snyder column
or a rotary evaporator. Rinse sample Container No. 2 three times with
small portions of toluene and add these to the concentrated solution
and concentrate further to no less than 5 mL. This residue contains
particulate matter removed in the rinse of the train probe and nozzle.
Rinse the concentrated material from Container No. 2 into the glass
extraction thimble containing the filter and the XAD-2 resin.
    11.1.5 Transfer the solvent contained in the collection beaker to
the extraction apparatus solvent reservoir. Rinse the beaker into the
Soxhlet extraction apparatus solvent reservoir three times with small
portions of toluene.
    11.1.6 Container No. 3 (Impinger Water and Rinses). For PAH and PCB
analysis, transfer the contents of Container No. 3 to a separatory
funnel. Adjust to pH 2 with 6 N sulfuric acid, if necessary. Rinse the
sample container with three successive 10-mL aliquots of the toluene
and these rinses to the separatory funnel. Extract the sample by
vigorously shaking the separatory funnel for 5 minutes. After complete
separation of the phases, remove the solvent and filter it through a
bed of precleaned, dry sodium sulfate into the Soxhlet extraction
apparatus solvent reservoir. Repeat the extraction step two additional
times. Adjust the pH to 11 with 6 N sodium hydroxide, re-extract the
impinger water and rinses, and filter it through a bed of precleaned,
dry sodium sulfate into the Soxhlet extraction apparatus solvent
reservoir. Rinse the sodium sulfate into the extraction apparatus
solvent reservoir with fresh solvent and discard the desiccant.
    11.1.7 Add the appropriate pre-extraction spikes for the compound
classes being analyzed (Tables 23-7, 23-8, and 23-9 of this method) to
the extraction thimble containing the combined filter and adsorbent
sample fractions. Cover the contents of the extraction thimble with the
cleaned glass wool plug to prevent the XAD-2 resin from splashing into
the solvent reservoir of the extractor. Place the extraction thimble
into the Soxhlet extraction apparatus.
    11.1.8 Pour additional toluene to fill the reservoir approximately
two-thirds capacity. Add PTFE boiling chips and assemble the apparatus.
    11.1.9 Adjust the heat source to cause the extractor to cycle
approximately three times per hour. Extract the sample for sufficient
time to meet the pre-extraction spike recovery performance criteria in
Section 13 of this method. The solvent should cycle completely through
the system a minimum of 48 times.

    Note: Samples containing high carbon particulate loading, such
as those collected downstream of an activated carbon injection
system, may require extended extraction time or treatment such as
those described in Stieglitz 1986.

    11.2 Sample Aliquots for Cleanup and Analysis.
    11.2.1 After extraction, allow the Soxhlet apparatus to cool.
    11.2.2 Initial Extract Concentration. You may perform an initial
concentration of the sample extract using the techniques (e.g., Kuderna
Danish, rotary evaporation, nitrogen blowdown) found to recover pre-
extraction isotopically labeled compounds sufficient to meet the
performance criteria in Section 13 of this method. Concentrate initial
extracts in toluene using a heating mantle and three-ball Snyder column
or a rotary evaporator. Concentrate the field train proof blank and
batch blank samples in the same manner as samples.

    Note: For samples requiring PCB or PAH analysis, you should
perform the initial concentration using a three-ball Snyder column
on the original extraction receiver flask. To meet isotopically
label spike recoveries for low molecular weight PAHs and PCBs, do
not evaporate samples to dryness.

    11.2.3 Allow the sample to cool. You should use a minimum of one
half of the sample extract for PCDD/PCDF analysis. You may archive the
remaining sample extract or further split the extract for PCB and/or
PAH analysis and archive.
    11.2.4 If necessary, further concentrate the sample for cleanup and
analysis using concentration techniques (e.g., Kuderna Danish, rotary
evaporation, nitrogen blowdown) found to recover pre-extraction
isotopically labeled compounds sufficient to meet the performance
criteria in Section 13 of this method.
    11.3 Sample Cleanup and Fractionation. You may process a separate
aliquot/split of the sample extract for each of the compound classes

analyzed by this method. Sample cleanup for each compound class may
include techniques in addition to column chromatography such as acid/
base back-extraction or high-performance liquid chromatography (HPLC)
to isolate target compounds from interferences. This section includes a
description of column chromatography shown to meet the performance
criteria in Sections 9.2 and 13 of this method. The following sample
cleanup and fractionation procedures are recommended but not required.
You may modify cleanup column dimensions to meet manual or automated
cleanup procedures as technology changes and improves. You must
evaluate the cleanup and fractionation procedures used to confirm
acceptable recovery of isotopically labeled standards. The alternative
procedures must provide sufficient cleanup to meet method
identification criteria (Section <IP_ADDRESS> of this method) and recovery
criteria (Section 9.2 of this method). Section 13 of this method
summarizes the method performance requirements.

    Note:  Recommendations in this section provide a cleanup
approach that may allow multiple compound class measurement from a
single aliquot of the original sample extract. Typically,
Florisil[supreg] and alumina are used to separate PAH and
chlorobiphenyl ether compounds from PCDD and PCDF target compounds.
Use acid, neutral, and basic silica gel and cleanup procedures to
remove nonpolar and polar interferences from samples destined for
PCB and PCDD/PCDF analysis. Use Carbopack[supreg]/Celite[supreg] (or
other equivalent carbon-based column material) to remove other
nonpolar interferences.

    11.3.1 PAH and PCDEs Fractionation and Cleanup. You may use a
Florisil[supreg] column to remove PAHs and PCDEs from a sample. You may
also fractionate samples using Florisil[supreg] as the first cleanup
step to separate PAH for analysis.

    Note:  High concentrations of PAHs may interfere with mass
spectrometer lock mass or saturate the source, leading to failure of
performance criteria for PCDD/PCDF or PCB analysis.

    <IP_ADDRESS> Pack a 6-mm ID chromatographic column or equivalent
diameter glass pipet with a glass wool plug followed by approximately
1.5 g (approximately 2 mL) of activated Florisil[supreg]. Add
approximately 1 cm (approximately 1 mL) of anhydrous sodium sulfate
followed by a glass wool plug to the head of the column. Pre-elute the
column with 10 mL of methylene chloride followed by 10 mL of hexane and
discard the eluate.
    <IP_ADDRESS> When the solvent is within 1 mm of the packing, transfer
the concentrated extract (up to 5 mL) to the top of the
Florisil[supreg] column, rinse the sample container twice with 1 to 2
mL of hexane, adding each rinse to the column, and elute the column
with 35 mL of 5-percent dichloromethane in hexane. This fraction
(Fraction 1) should contain target PCBs, and selected hydrocarbons and
chlorinated monoaromatic compounds.
    <IP_ADDRESS> Elute the column with 35 mL of 15-percent of
dichloromethane in hexane and collect the eluate. This fraction
(Fraction 2) should contain target PCDD/PCDF compounds.
    <IP_ADDRESS> Elute the column with 50 mL of 50-percent dichloromethane
in hexane. The fraction (Fraction 3) should contain target PAHs.
    <IP_ADDRESS> If necessary to remove any remaining polar organic
compounds, elute the column with 70 mL of 15-percent acetone in hexane.
    11.3.2 PCDD/PCDF and PCB Fractionation and Cleanup. You may remove
PAHs from the original aliquot of extract used for PCDD/PCDF analysis
as described in Section 11.3.1 of this method. Design the column
cleanup chromatography for PCDD/PCDFs and PCBs such that two
consecutive fractions are collected (one with PCDD/PCDFs and one with
PCBs) without impacting the DLs. Depending on the source and sample
matrix of the original sample, one or more of the following column
cleanup approaches may be necessary to remove polyhalogenated diphenyl
ethers. You may use any number of permutations found in the referenced
literature for this cleanup if the pre-extraction standard recoveries
from field and batch blank samples meet the associated performance
criteria in Section 13 of this method. Alternatively, you may use an
automated cleanup approach that meets the labeled spike recovery
requirements in Section 13 of this method.
    <IP_ADDRESS> Silica Gel Column Chromatography. Pack one end of a glass
column, approximately 20 mm ID x 230 mm long, with glass wool. Add in
sequence to the glass column, 1 g of silica gel, 2 g of sodium
hydroxide impregnated silica gel, 1 g of silica gel, 4 g of acid-
modified silica gel, 1 g of silica gel, and 1 cm layer of anhydrous
sodium sulfate. Pre-elute the column with 30 to 50 mL of hexane leaving
a small quantity of hexane above the sodium sulfate layer. Discard the
pre-elution hexane. Add the sample extract, dissolved in 5 mL of hexane
to the head of the column. Allow the sample to flow into the column
leaving a small quantity of hexane above the sodium sulfate layer.
Rinse the extract container with two additional 5-mL rinses of hexane
and apply each rinse to the column separately as the previous addition
elutes. Elute the column with an additional 90 mL of hexane and retain
the entire eluate. Concentrate this solution to a volume of about 1 mL
using the nitrogen evaporative concentrator (see Section 6.3.5 of this
method).
    <IP_ADDRESS> Silver Nitrate Silica Gel Column Chromatography. Pack a
column (6 mm ID, 150 mm in length) sequentially with 1 g of silica gel
and 1 g of 10-percent silver nitrate silica gel followed by a layer of
about 10 mm of sodium sulfate (anhydrous). Wash the column sufficiently
with hexane, elute until the liquid level reaches to the upper end of
the column, and then load the sample solution that is concentrated
under vacuum to be about 5 mL. Wash the inner side several times with a
small amount of hexane, elute with 200 mL of hexane at a flow rate
about 2.5 mL/min (approximately one drop per second) to elute PCDDs.
    <IP_ADDRESS> Multi-layer Silica Gel Column Chromatography. You may use
a multi-layer silica gel column in place of separate silica columns.
Pack a column of 20 mm ID and 300 mm in length sequentially by the dry
pack method with 0.9 g of silica gel, 3.0 g of 2-percent potassium
hydroxide silica gel, 0.9 g of silica gel, 4.5 g of 44-percent sulfuric
acid silica gel, 6.0 g of 22-percent sulfuric acid silica gel, 0.9 g of
silica gel, 3.0 g of 10-percent silver nitrate silica gel, 2.0 g of
silica gel and 6.0 g of sodium sulfate (anhydrous). Wash the column
sufficiently with hexane, elute until the liquid level reaches to the
upper end of the column, and then load the sample solution. Wash the
inner side of the transfer vessel several times with a small amount of
hexane, elute with 150-200 mL of hexane at a flow rate about 2.5 mL/min
(approximately one drop per second) to elute PCDDs/PCDFs.
    <IP_ADDRESS> Basic Alumina Column Chromatography. Pack a column (20 mm
ID, 300 mm in length) with approximately 6 to 12 g of basic alumina.
Pre-elute the column with 50 to 100 mL of hexane. Transfer the
concentrated extract from the previous column cleanup to the top of the
basic alumina column. Allow the sample to flow into the column leaving
a small quantity of solvent above the top of the bed. Rinse the extract
container with two additional 1-mL rinses of hexane and apply each
rinse to the column separately as the previous addition elutes. Elute
the column with 100 mL hexane to remove the interferences. Elute the
PCDDs/PCDFs from the column with 20 to 40 mL of 50-percent

methylene chloride in hexane. The ratio of methylene chloride to hexane
may vary depending on the activity of the alumina used in the column
preparation. Do not let the head of the column go without solvent. The
first 100 mL hexane eluate is not used for subsequent PCDD/PCDF
analysis. The eluate is concentrated to approximately 0.5 mL using the
nitrogen evaporative concentrator.
    <IP_ADDRESS> Carbopack[supreg] C/Celite[supreg] 545 Column or
Equivalent. Cut both ends from a 10 mL disposable Pasteur pipette (see
Section 6.4.1 of this method) to produce a 10 cm column. Fire-polish
both ends and flare both ends if desired. Insert a glass wool plug at
one end and pack the column with 0.55 g of Carbopack[supreg]/
Celite[supreg] (see Section <IP_ADDRESS> of this method) to form an
adsorbent bed approximately 2 cm long. Insert a glass wool plug on top
of the bed to hold the adsorbent in place. Pre-elute the column with 5
mL of toluene followed by 2 mL of methylene chloride:methanol:toluene
(15:4:1 v/v), 1 mL of methylene chloride:cyclohexane (1:1 v/v), and 5
mL of hexane. If the flow rate of eluate exceeds 0.5 mL/minute, discard
the column. Do not let the head of the column go without solvent. Add
the sample extract to the column. Rinse the sample container twice with
1 mL portions of hexane and apply separately to the column. Apply 2 mL
of hexane to the head of the column to complete the transfer. Elute the
interfering compounds with two 3 mL portions of hexane, 2 mL of
methylene chloride:cyclohexane (1:1 v/v), and 2 mL of methylene
chloride:methanol:toluene (15:4:1 v/v). Discard the eluate. Invert the
column and elute the PCDDs/PCDFs with 20 mL of toluene. If carbon
particles are present in the eluate, filter through glass-fiber filter
paper. Concentrate the eluate to approximately 0.5 mL using the
nitrogen evaporative concentrator for further cleanup or analysis by
HRGC/HRMS.
    11.4 PCDD, PCDF, PCB and PAH Analysis.
    11.4.1 Analyze the sample with an HRGC/HRMS using the instrumental
parameters in Sections 11.4.2 and 11.4.3 of this method.
    <IP_ADDRESS> Immediately prior to analysis, add an aliquot (typically
20 microliters ([micro]l)) of the pre-analysis standard solution(s)
from Table 23-7, 23-8, or 23-9 of this method to each sample as
appropriate for the compounds you are measuring by this method.
    <IP_ADDRESS> Inject an aliquot of the sample extract into the GC. You
may perform separate analyses using different GC columns for each of
the target compound classes. A 1-[micro]l aliquot of the extract is
typically injected into the GC. Perform calibration and analysis for
each target compound class using the same sample injection volume and
concentration calculations.
    <IP_ADDRESS>.1 If target compounds are not resolved sufficient from
other target compounds or interferences in the sample to meet the
requirements in Section <IP_ADDRESS> or <IP_ADDRESS> of this method, as
applicable to the compound class being analyzed, or as otherwise
specified in an applicable regulation, permit, or other requirement,
analyze another aliquot of the sample using an alternative column that
provides elution order to uniquely quantify the target compounds
subject to interference on the first GC column.
    <IP_ADDRESS>.2 You may use column systems other than those recommended
in this method provided the analyst is able to demonstrate, using
calibration and performance checks, that the alternative column system
is able to meet the applicable specifications of Section <IP_ADDRESS> or
<IP_ADDRESS> of this method.
    11.4.2 Example Gas Chromatograph Operating Conditions.
    <IP_ADDRESS> Injector. Configured for capillary column, splitless, 250
[deg]C (482 [deg]F).
    <IP_ADDRESS> Carrier Gas. Helium, 1 to 2 mL/min.
    <IP_ADDRESS> Oven. Optimize the GC temperature program to achieve the
required separation and target compound recovery for the GC column in
use. Table 23-16 of this method presents the typical conditions for a
DB5-MS column.
    11.4.3 High-Resolution Mass Spectrometer.
    <IP_ADDRESS> Ionization Mode. Electron ionization.
    <IP_ADDRESS> Source Temperature. Maintain the source temperature in the
range of 250 to 300 [deg]C (482 to 572 [deg]F).
    <IP_ADDRESS> Ion Monitoring Mode. Tables 23-4, 23-5, and 23-6 of this
method summarize the various ions to be monitored for PCDD/PCDFs, PAHs,
and PCBs, respectively.
    <IP_ADDRESS> Identification Criteria for Target Compounds. Use the
following identification criteria for the characterization of target
compounds in this method. The available native and isotopically labeled
standards allow the unique identification of all PCDD/PCDF, PAH, and
selected PCB congeners required in this method. Also see Sections 13.12
and 13.13 of this method for identification criteria for PCDD/PCDF/PCB
and PAH target compounds, respectively.
    <IP_ADDRESS>.1 For PCDD/PCDFs and PCBs, Table 23-15 of this method
provides the integrated ion abundance ratio of primary and secondary
target compound ions for the identification of target compounds. When
the ion abundance ratio for a target analyte is outside the performance
criteria, you may reanalyze samples on an alternative GC column to
resolve chemical interferences, tune the mass spectrometer to operate
at a higher mass resolution to discriminate against the
interference(s), and/or reprocess an archived sample through the
cleanup procedure to remove the interference(s). Report analysis
results that do not meet the identification criteria as an estimated
maximum possible concentration (EPC). Calculate the EPC separately for
each quantitation ion, if present, and report the lower value as the
EPC. This method does not consider EPC-flagged data to be zero
concentrations.

    Note:  Some EPCs are caused by poor ion statistics when the
concentration of the target compound is at or near the DL. If you
use the primary ion to determine and report the target compound
concentration in these cases, reanalysis of samples is not
necessary.

    <IP_ADDRESS>.2 The retention time for the analytes must be within 3
seconds of the corresponding \13\ C-labeled pre-extraction standard.
    <IP_ADDRESS>.3 The signals for the two exact masses in Tables 23-4 and
23-6 of this method for PCDD/PCDFs and PCBs, respectively, must be
present and must reach their maximum response within two seconds of
each other.
    <IP_ADDRESS>.4 Identify and quantify specific target compounds or
isomers that do not have corresponding \13\ C-labeled standards by
comparing to the pre-extraction labeled standard of the same compound
class with the nearest retention time to target compound.
    <IP_ADDRESS>.5 For the identification of specific PCB isomers, the
retention time of the native congener must be within 0.006 relative
retention time (RRT) units of the pre-extraction isotopically labeled
standard.
    <IP_ADDRESS>.6 For qualitative identification, the S/N ratio for the GC
signal present in every selected ion current profile for native
compound response must be greater than or equal to 2.5. The ion
abundance ratios must be within the control limits in Table 23-15 of
this method for the compound class measured.
    <IP_ADDRESS>.7 The confirmation of 2,3,7,8-TeCDD and 2,3,7,8-TeCDF must
satisfy the separation criteria in Section

<IP_ADDRESS> of this method and all the identification criteria specified
in Sections <IP_ADDRESS>.1 through <IP_ADDRESS>.6 of this method.
    <IP_ADDRESS>.8 Chlorodiphenyl Ether Interference. If chromatographic
peaks are detected at the retention time of any PCDDs/PCDF in any of
the m/z channels used to monitor chlorodiphenyl ethers, there is
evidence of a positive interference and you may opt to flag data noting
the interference and keep the value to calculate PCDD/PCDF
concentration as EPC or conduct a complete reanalysis to remove or
shift the interference. This method recommends alumina (see Section
<IP_ADDRESS> of this method) and Florisil[supreg] (see Section 11.3.1 of
this method) liquid column chromatography packing materials for removal
of chlorodiphenyl ethers during sample cleanup.
    <IP_ADDRESS>.9 Set the mass spectrometer lock channels as specified in
Tables 23-4, 23-5, and 23-6 of this method for PCDD/PCDFs, PAHs, and
PCBs, respectively. Monitor the quality control check channels to
verify instrument stability during the analysis. If the signal varies
by more than 25 percent from the average response, flag results for all
isomers at corresponding retention time as QCF. You have the option to
conduct additional cleanup procedures on an archived portion of the
sample if the archive is available, or dilution the original sample and
reanalysis or follow other quality review that demonstrates the target
analyte and its corresponding isotopically labeled standard are equally
affected by the change in the control check channels. When you conduct
a complete reanalysis, reanalyze all concentration calculations based
on the reanalyzed sample.
    <IP_ADDRESS>.10 Identification Criteria for PAHs. The RRT between each
native and labeled compound must be within 0.006 RRT units. The signals
for the characteristic ion listed in Table 23-5 of this method must be
present.
    <IP_ADDRESS> Quantitation. Measure the response of each native target
compound and the corresponding pre-extraction standard. Use the
equation in Section 12.7 of this method to sum the peak areas for the
two quantitation ions monitored for each analyte and calculate the mass
of the target compound(s) in the injection using the CCV RF. Use the
pre-extraction recovery standard compounds to correct the homologous
congener results for variations in recovery from the extraction,
cleanup, and concentration steps of the analysis. Recovery of pre-
extraction standards must meet minimum specifications (in Section 9.2.
of this method) to ensure that the method performance and reliability
have not been compromised by unacceptable losses during sample
processing. Table 23-17 of this method shows the assignments for single
isotopically labeled compounds for use in calculating the response
factor and the concentrations of PCBs. Recoveries of all labeled
standards must meet the minimum recovery specifications in this method
and unacceptably low recoveries are an indication of the sample
processing step that caused the low recoveries.
    <IP_ADDRESS>.1 Use Eq. 23-7 to calculate the mass of each target
compound or group in the extract.
    <IP_ADDRESS>.2 Use Eq. 23-8 to calculate the mass per dscm of each
target compound or group in the sample.
    <IP_ADDRESS>.3 Quantify indigenous PCDD and PCDF in its homologous
series using the corresponding native and pre-extraction standard
response in its homologous series. For example, use \13\C12-
2,3,7,8-tetra chlorinated dibenzodioxin to calculate the concentrations
of all other tetra chlorinated isomers.
    <IP_ADDRESS>.4 As an option or as required or specified in applicable
regulations, permits, or other requirements, you may quantify any or
all other PCB congeners as resolved or coeluting combinations using the
response of the nearest eluting native target PCB and the response of
the pre-extraction isotopic label assigned in appendix A to this
method.
    <IP_ADDRESS>.5 As an option or as required or specified in applicable
regulations, permits, or other requirements, report the total
concentration of congeners at a given level of chlorination (homolog;
i.e., total TrCB, total PeCB, total HxCB) by summing the concentrations
of all congeners identified in the retention time window for the
homologs as assigned in appendix A to this method.
    <IP_ADDRESS>.6 As an option or if required in an applicable regulation,
permit or other requirement, total chlorinated biphenyls (CBs) may be
reported by summing all congeners identified at all window-defined
congeners (WDCs) as assigned in appendix A to this method.

12.0 Data Analysis and Calculations

    Note:  Same as Section 12 of Method 5 of appendix A-3 to 40 CFR
part 60, with the following additions.

    12.1 Nomenclature.
    Aai = Integrated ion current (area) of the noise for the primary
and secondary m/z values at the retention time of the analyte.
    A*ci = Integrated ion current (area) of the primary and secondary
m/z values of the pre-extraction (internal) standard i in the
calibration standard.
    A1l = Integrated ion current of the primary m/z values
for the isotopically labeled compound (assigned in Tables 23-4, 23-5,
and 23-6 of this method).
    A1n = Integrated ion current of the primary m/z values
for the target native compound.
    A2l = Integrated ion current of the secondary m/z's for
the isotopically labeled compound. For PAH A2l = 0.
    A2n = Integrated ion current of the secondary m/z values
for the target native compound. For PAH A2n = 0.
    Cl = The concentration of the labeled compound used to
perform isotope recovery correction, pg/[mu]L. Tables 23-4, 23-5, and
23-17 of this method provide the compound mass assignments.
    Cn = The concentration of the target native compound,
pg/[mu]L.
    Ci = Concentration of target native compound i in the
sample, pg/[mu]L.
    Cidscm = Concentration of target native compound i in
the emission gas, pg/dscm.
    Ciext = Concentration of target native compound i in the
extract, pg.
    CT = Total concentration of target compounds in the
sample, pg/[mu]L.
    D = Difference in the RRF of the continuing calibration
verification compared to the average RRF of the initial calibration,
percent (%).
    dscm = Dry standard cubic meters of gas volume sample measured by
the dry gas meter, corrected to standard conditions.
    Hai = Summed heights of the noise at the retention time
of the analyte in the two analyte channels.
    H*ci = Summed heights of the noise at the primary and secondary m/
z's of the pre-extraction standard i in the calibration standard.
    mi = Mass of compound i, pg.
    m*i = Mass of pre-extraction (internal standard)
compound i, pg.
    n = Number of values.
    NOAAT = National Oceanic and Atmospheric Administration isotopic
labeled congener for PCB of interest.
    R* = Recovery of labeled compound standards, %.
    RRFi = Relative response factor of a target compound at
calibration level i.
    RRFccv = Relative response factor of a target compound
in the continuing calibration verification.
    RSD = Relative standard deviation, in this case, of RRFs over the
five calibration levels, %.
    SDRRF = Standard deviation of initial calibration RRFs.
    Vext = Extract volume, [mu]L.

    WHOT = World Health Organization acronym used to designate WHO
isotopic labeled toxic analog.
    WDC = Window-defined congener representing an isotopically labeled
PCB that defines the beginning or end of a retention time window
bracketing a PCB homolog level of chlorination.
    12.2 Individual Compound RRF for Each Calibration Level i. The
equation for the response factor of each target native compound
relative to its labeled pre-extraction spike analog includes the
integrated ion current of both the primary and secondary m/z values for
each compound in the calibration standard. Use this equation to
calculate the RRF for the continuing calibration verification for
comparison to the average RRF from the initial calibration.
[GRAPHIC] [TIFF OMITTED] TP14JA20.000

    12.3 Average RRF for Each Compound Over the Five Calibration
Levels.
[GRAPHIC] [TIFF OMITTED] TP14JA20.001

    12.4 Percent RSD of the RRFs for a Compound Over the Five
Calibration Levels. The requirement for the initial calibration RSD is
in Section 13.10 and Table 23-14 of this method.
[GRAPHIC] [TIFF OMITTED] TP14JA20.002

    12.5 Standard Deviation of the RRFs for a Compound Over the Five
Calibration Levels.
[GRAPHIC] [TIFF OMITTED] TP14JA20.003

    12.6 Percent Difference of the RRF of the Continuing Calibration
Verification Compared to the Average RRF from the Initial Calibration
for Each Target Compound. The requirement for the continuing
calibration verification percent difference is in Section 13.11 and
Table 23-14 of this method.
[GRAPHIC] [TIFF OMITTED] TP14JA20.004

    12.7 Concentration of Individual Target Compound i in the Extract
by Isotope Dilution (pg/[mu]L). This equation corrects for the target
native compound recovery by its labeled pre-extraction spike analog. To
accomplish this the pre-extraction spike, labeled compound levels must
remain constant.
[GRAPHIC] [TIFF OMITTED] TP14JA20.005

    12.8 Concentration of the Individual Target Compound i in the
Sample Extract (pg).
[GRAPHIC] [TIFF OMITTED] TP14JA20.006

    12.9 Mass of the Individual Target Compound or Group i in the
Emission Gas (pg/dscm).
[GRAPHIC] [TIFF OMITTED] TP14JA20.007

    12.10 Recovery of Labeled Compound Standards. Use this equation to
determine the recovery of any labeled compounds, including pre-sampling
spikes, pre-extraction filter spike, pre-extraction spikes, pre-
analysis spikes. The recovery performance criteria for these spikes is
in Sections 13.15, 13.16, and 13.17 of this method.
[GRAPHIC] [TIFF OMITTED] TP14JA20.008

    12.11 Estimated Detectable Limit (EDL).
    [GRAPHIC] [TIFF OMITTED] TP14JA20.009

    12.12 Total Concentration.
    [GRAPHIC] [TIFF OMITTED] TP14JA20.010

    Note: Unless otherwise specified in applicable regulations,
permits or other requirements, count any target compounds reported
as non-detected as EDL when calculating the concentration of target
compounds in the sample.

13.0 Method Performance

    13.1 Residual Toluene Quality Check. If adsorbent resin is cleaned
or recleaned by the laboratory, a quality control check for residual
toluene must be <=1,000 [mu]g/g of adsorbent. See appendix B to this
method for procedures to assess residual toluene.
    13.2 Field Train Proof Blank and Batch Blank Sample Assessment.
Conduct at least one field train proof blank for each test series at a
single facility or sampling location. Analyze at least one batch blank
sample during an analytical sequence or every 24 hours, whichever is
shorter. Native target compound concentrations must be less than or
equal to three times the EDL of the method or 10 times lower than the
quantitation limit required by the end use of the data, whichever is
higher. If blank assessment fails this criterion, flag sample data from
this test with explanation that the blank samples failed the method
criteria.
    13.3 GC column systems used to measure PCDD/PCDFs must meet the
column separation requirements in Section <IP_ADDRESS> of this method and
the applicable requirements in Sections <IP_ADDRESS> and <IP_ADDRESS> of this
method using calibration and batch blank performance checks. Failure to
meet this chromatographic resolution criterion requires data from this
analysis to be flagged explaining the potential bias of the results. A
mid-concentration standard containing all of the native target PCDD/
PCDFs may be used to demonstrate this requirement.
    13.4 GC column systems used to measure PAHs must meet the column
separation requirements in Section <IP_ADDRESS> of this method and the
applicable requirements in Sections <IP_ADDRESS> and <IP_ADDRESS> of this
method using calibration and batch blank performance checks. Failure to
meet this chromatographic resolution criterion requires data from this
analysis to be flagged explaining the potential bias of the results.
    13.5 GC systems used to measure PCBs must meet the column
separation requirements in Section <IP_ADDRESS> of this method and the
applicable requirements in Sections <IP_ADDRESS> and <IP_ADDRESS> of this
method of this method using calibration and batch blank performance
checks, and be able to achieve unique resolution and identification of
the toxics for determination of a TEQPCB using TEFs
(American Society of Mechanical Engineers 1984).
    13.6 Confirmation Column. If target compounds are not sufficiently
resolved from other target compounds or interferences in the sample to
meet the requirements for target compounds in Sections 13.3, 13.4, and/
or 13.5 of this method, analyze another aliquot of the sample in a
separate run using an alternative column that provides elution order to
uniquely quantify the target compounds subject to interference on the
first GC column.
    13.7 Detection Limits. If the DLs as determined in Section 9.5 of
this method meet the target DLs shown in Tables 23-18, 23-19, and 23-20
of this method for the target compounds determined with this method,
the DLs

are considered acceptable. If the compound specific DLs are less than
50 percent of the emission standard, the DLs are acceptable. If the DL
requirements are not met, you must flag native compound data that fails
to meet these criteria and provide a description of the impact on the
data as part of the quality narrative for the sample analyses.
    13.8 Tune. Tune the HRGC/HRMS to meet the isotopic ratio criteria
listed in Table 23-15 of this method.
    13.9 Lock Channels. MS lock and quality control channels
recommended in Tables 23-4, 23-5, and 23-6 of this method for PCDD/
PCDFs, PCBs, or PAHs, respectively, must not vary >25 percent from the
average response. You may use PFK or perfluorotributylamine (FC43) as
your lock mass standard. You may choose lock masses within a SIM
descriptor window that demonstrates the least interference. Monitor the
quality control check channels specified in these tables to verify
instrument stability during the analysis. Flag data resulting from
failure to maintain lock channel signal or quality control check signal
during analysis (QCF).
    13.10 Initial Calibration.
    13.10.1 The RSD for mean RRF from each of the target analytes and
labeled standards in the calibration samples must not exceed the values
in Table 23-14 of this method.
    13.10.2 The S/N in every selected ion current profile must be >=10
for all unlabeled targets and labeled standards in the calibration
samples.
    13.10.3 The ion abundance ratios must be within the control limits
in Table 23-15 of this method.
    13.11 Continuing Calibration.
    13.11.1 The RRF for each unlabeled and labeled compound measured in
a continuing calibration verification must not deviate from the initial
calibration by more than the limits shown in Table 23-14 of this
method.
    13.11.2 The ion abundance ratios must be within the control limits
in Table 23-15 of this method.
    13.12 Compound Identification for PCDD/PCDFs and PCBs.
    13.12.1 Target compounds must have ion abundance ratios within the
control limits in Table 23-15 of this method. When the ion abundance
ratio for a target analyte is outside the performance criteria, report
the results as EPC (see Section 3.7 of this method). PAH target
compounds have single ion identifiers with no ion abundance ratio
requirement.
    13.12.2 Report analysis results that do not meet the identification
criteria as an EPC.
    13.12.3 The Retention time (RT) for the analytes must be within 3
seconds of the corresponding labeled pre-extraction standard.
    13.12.4 The monitored ions, shown in Table 23-4 of this method for
a given PCDD/PCDF, must reach their maximum response within 2 seconds
of each other.
    13.12.5 The monitored ions, shown in Table 23-6 of this method for
a given PCB, must reach their maximum response within 2 seconds of each
other.
    13.12.6 For the identification of specific PCB isomers, the
retention time of the native congener must be within 0.006 RRT units of
the pre-extraction standard RRT.
    13.12.7 The chromatographic overlap of 2,3,4,7,8-PeCDF,
2,3,4,6,7,8-HxCDF, and 1,2,3,7,8,9-HxCDF peaks with interference peaks
must not exceed 25 percent.
    13.12.8 Identify and quantify isomers that do not have
corresponding labeled pre-extraction standards by comparing to the pre-
extraction labeled standard of the same compound class with the nearest
RT to the target compound.
    13.12.9 If chromatographic peaks are detected at the RT of any
PCDD/PCDF in any of the m/z channels used to monitor chlorophenyl
ethers, there is evidence of interference and positive bias. Data must
be flagged to indicate an interference. You may report the total with
bias for the affected target. To reduce the bias, you may use a
confirmatory column or perform additional clean up on an archived
sample followed by reanalysis.
    13.13 Compound Identification for PAHs.
    13.13.1 The signals for the characteristic ion listed in Table 23-5
of this method must be present.
    13.13.2 The RRT between each native and labeled compound must be
within 0.006 RRT units.
    13.14 Filter, Adsorbent Resin, Glass Wool, Water and Laboratory
Batch Blank Quality Control Check. Target levels must be <= three times
the EDL of the method or 10 times lower than the quantitation limit
required by the end use of the data, whichever is higher.

    Note:  You must analyze batch blank samples at least once during
each analytical sequence or every 24 hours, whichever is shorter.

    13.15 Pre-sampling Spike Recovery and Pre-extraction Filter Spike
Recovery. Recoveries of all pre-sampling isotopically labeled spike
compounds standards added to the sample and all pre-extraction filter
recovery spike compounds added to the filter must be between 70 and 130
percent (Tables 23-7, 23-8, and 23-9 of this method).
    13.15.1 If the recovery of the pre-sampling spike is below 70
percent, the sampling runs are not valid, and you must repeat the
invalid runs. As an alternative, you do not have to repeat the invalid
sampling runs if the average pre-sampling adsorbent spike recovery is
25 percent or more and you divide the final results by the average
fraction of pre-sampling adsorbent spike recovery.
    13.15.2 If the recovery of the pre-extraction filter spike is below
70 percent, the sampling recovery is not valid, and you must flag the
test run results.
    13.16 Pre-extraction Spike Recovery. Recoveries of all pre-
extraction isotopically labeled spike compounds standards added to the
sample must be between 20 to 130 percent for PCDD/PCDFs and PAHs
(Tables 23-7 and 23-8 of this method) and between 20 to 145 percent for
PCBs (Table 23-9 of this method).
    13.17 Pre-analysis Spike Sensitivity. Response of all pre-analysis
isotopically labeled spike compounds must show a S/N for every selected
ion current profile of >=10. Poor sensitivity compared to initial
calibration response may indicate injection errors or instrument drift.
    13.18 Requirements for Equivalency. The Administrator considers any
modification of this method, beyond those expressly permitted in this
method as options, to be a major modification subject to application
and approval of alternative test procedures following EPA Guidance
Document 22 currently found at: https://www.epa.gov/emc/emc-guideline-documents.
    13.19 Records. As part of the laboratory's quality system, the
laboratory must maintain records of modification to this method.

14.0 Pollution Prevention

    The target compounds used as standards in this method are prepared
in extremely small amounts and pose little threat to the environment
when managed properly. Prepare standards in volumes consistent with
laboratory use to minimize the disposal of excess volumes of expired
standards.

15.0 Waste Management

    15.1 The laboratory is responsible for complying with all federal,
state, and local regulations governing waste management, particularly
the hazardous waste identification rules and land disposal
restrictions, and for protecting the air, water, and land by minimizing
and controlling all releases from fume

hoods and bench operations. The laboratory must also comply with any
sewage discharge permits and regulations. The EPA's Environmental
Management Guide for Small Laboratories (EPA 233-B-98-001) provides an
overview of requirements.
    15.2 Samples containing hydrogen chloride or sulfuric acid to pH <2
are hazardous and must be neutralized before being poured down a drain
or must be handled as hazardous waste.
    15.3 For further information on waste management, consult The Waste
Management Manual for Laboratory Personnel and Less is Better-
Laboratory Chemical Management for Waste Reduction, available from the
American Chemical Society's Department of Government Relations and
Science Policy, 1155 16th Street NW, Washington, DC 20036.

16.0 Bibliography

    1. American Society of Mechanical Engineers. Analytical Procedures
to Assay Stack Effluent Samples and Residual Combustion Products for
Polychlorinated Dibenzo-p-Dioxins (PCDD) and Polychlorinated
Dibenzofurans (PCDF). Prepared for the U.S. Department of Energy and
U.S. Environmental Protection Agency. Washington, DC. December 1984. 23
p.
    2. American Society of Mechanical Engineers. Sampling for the
Determination of Chlorinated Organic Compounds in Stack Emissions.
Prepared for U.S. Department of Energy and U.S. Environmental
Protection Agency. Washington DC. December 1984. 25 p.
    3. Fishman, V.N., Martin, G.D. and Lamparski, L.L., Comparison of a
variety of gas chromatographic columns with different polarities for
the separation of chlorinated dibenzo-p-dioxins and dibenzofurans by
high-resolution mass spectrometry, Journal of Chromatography A 1139
(2007) 285-300.
    4. International Agency for Research on Cancer. Environmental
Carcinogens Methods of Analysis and Exposure Measurement, Volume 11--
Polychlorinated Dioxins and Dibenzofurans. IARC Scientific Publications
No. 108, 1991.
    5. Stieglitz, L., Zwick, G., Roth, W. Investigation of different
treatment techniques for PCDD/PCDF in fly ash. Chemosphere 15: 1135-
1140; 1986.
    6. Triangle Laboratories. Case Study: Analysis of Samples for the
Presence of Tetra Through Octachloro-p-Dibenzodioxins and
Dibenzofurans. Research Triangle Park, NC. 1988. 26 p.
    7. U.S. Environmental Protection Agency. Method 8290--The Analysis
of Polychlorinated Dibenzo-p-dioxin and Polychlorinated Dibenzofurans
by High-Resolution Gas Chromatography/High-Resolution Mass
Spectrometry. In: Test Methods for Evaluating Solid Waste. Washington,
DC. SW-846.
    8. U.S. Environmental Protection Agency. Office of Air Programs
Publication No. APTD-0576: Maintenance, Calibration, and Operation of
Isokinetic Source Sampling Equipment. Research Triangle Park, NC. March
1972.
    9. U.S. Environmental Protection Agency. Method 1625C-Semivolatile
Organic Compounds by Isotope Dilution GCMS.
    10. U.S. Environmental Protection Agency. Method 1613B-Tetra-
through Octa-Chlorinated Dioxins and Furans by Isotope Dilution HRGC/
HRMS.
    11. U.S. Environmental Protection Agency. Method 1668C-Chlorinated
Biphenyl Congeners in Water, Soil, Sediment, Biosolids, and Tissue by
HRGC/HRMS.12. Tondeur, Y., Nestrick, T., Silva, H[eacute]ctor A.,
Vining, B., Hart, J. Analytical procedures for the determination of
polychlorinated-p-dioxins, polychlorinated dibenzofurans, and
hexachlorobenzene in pentachlorophenol, Chemosphere Volume 80, Issue 2,
June 2010 pages 157-164.

17.0 Tables, Diagrams, Flowcharts, and Validation Data

          Table 23-1--Polychlorinated Dibenzo-p-Dioxin and Polychlorinated Dibenzofuran Target Analytes
----------------------------------------------------------------------------------------------------------------
                                             CAS \a\ registry                                   CAS \a\ registry
     Polychlorinated dibenzo-p-dioxins            number        Polychlorinated dibenzofurans         No.
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TeCDD.............................          1746-01-6  2,3,7,8-TeCDF.................         51207-31-9
1,2,3,7,8-PeCDD...........................         40321-76-4  1,2,3,7,8-PeCDF...............         57117-41-6
1,2,3,4,7,8-HxCDD.........................         39227-28-6  2,3,4,7,8-PeCDF...............         57117-31-4
1,2,3,6,7,8-HxCDD.........................         57653-85-7  1,2,3,4,7,8-HxCDF.............         70648-26-9
1,2,3,7,8,9-HxCDD.........................         19408-74-3  1,2,3,6,7,8-HxCDF.............         57117-44-9
1,2,3,4,6,7,8-HpCDD.......................         35822-46-9  1,2,3,7,8,9-HxCDF.............         72918-21-9
Total TeCDD...............................         41903-57-5  2,3,4,6,7,8-HxCDF.............         60851-34-5
Total PeCDD...............................         36088-22-9  1,2,3,4,6,7,8-HpCDF...........         67562-39-4
Total HxCDD...............................         34465-4608  1,2,3,4,7,8,9-HpCDF...........         55673-89-7
Total HpCDD...............................         37871-00-4  Total TeCDF...................         55722-27-5
Total OCDD................................          3268-87-9  Total PeCDF...................         30402-15-4
                                                               Total HxCDF...................         55684-94-1
                                                               Total HpCDF...................         38998-75-3
                                                               Total OCDF....................         39001-02-0
----------------------------------------------------------------------------------------------------------------
\a\ Chemical Abstract Service.

                           Table 23-2--Polycyclic Aromatic Hydrocarbon Target Analytes
----------------------------------------------------------------------------------------------------------------
                                              CAS \a\ registry       Polycyclic aromatic        CAS \a\ registry
     Polycyclic aromatic  hydrocarbons              No.                  hydrocarbons                 No.
----------------------------------------------------------------------------------------------------------------
Naphthalene................................            91-20-3  Chrysene.....................           218-01-9
2-Methylnapthalene.........................            91-57-6  Benzo[b]fluoranthene.........           205-99-2
Acenaphthylene.............................           208-96-8  Benzo[k]fluoranthene.........           207-08-9
Acenaphthene...............................            83-32-9  Perylene.....................           198-55-8
Fluorene...................................            86-73-7  Benzo[a]pyrene...............            50-32-8
Anthracene.................................           120-12-7  Benzo[e]pyrene...............           192-92-2
Phenanthrene...............................            85-01-8  Benzo[g,h,i]perylene.........           191-24-2
Fluoranthene...............................           206-44-0  Indeno[1,2,3-cd]pyrene.......           193-39-5
Pyrene.....................................           129-00-0  Dibenz[a,h]anthracene........            53-70-3
Benzo[a]anthracene.........................            56-55-3
----------------------------------------------------------------------------------------------------------------
\a\ Chemical Abstract Service.

                                                  Table 23-3--Polychlorinated Biphenyl Target Analytes
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                 CASb Registry No.                                                       CAS b Registry
                  PCB congener                       BZ No.a                                   PCB congener                BZ No.a            No.
--------------------------------------------------------------------------------------------------------------------------------------------------------
2,4'-DiCB......................................               8         34883-43-7  2,2',3,3',4,4'-HxCB..............             128         38380-07-3
2,2',5-TrCB....................................              18         37680-65-2  2,2',3,4,4',5'-HxCB..............             138         35065-28-2
2,4,4'-TrCB....................................              28          7012-37-5  2,2',4,4',5,5'-HxCB..............             153         35065-27-1
2,2',3,5'-TeCB.................................              44         41464-39-5  2,3,3',4,4',5-HxCB...............             156         38380-08-4
2,2',5,5'-TeCB.................................              52         35693-99-3  2,3,3',4,4',5'-HxCB..............             157         69782-90-7
2,3',4,4'-TeCB.................................              66         32598-10-0  2,3',4,4',5,5'-HxCB..............             167         52663-72-6
3,3',4,4'-TeCB.................................              77         32598-13-3  3,3',4,4',5,5'-HxCB..............             169         32774-16-6
3,4,4',5-TeCB..................................              81         70362-50-4  2,2',3,3',4,4',5-HpCB............             170         35065-30-6
2,2',4,5,5'-PeCB...............................             101         37680-73-2  2,2',3,4,4',5,5'-HpCB............             180         35065-29-3
2,3,3',4,4'-PeCB...............................             105         32598-14-4  2,2',3,4',5,5',6-HpCB............             187         52663-68-0
2,3,4,4',5-PeCB................................             114         74472-37-0  2,3,3',4,4',5,5'-HpCB............             189         39635-31-9
2,3',4,4',5-PeCB...............................             118         31508-00-6  2,2',3,3',4,4',5,6-OcCB..........             195         52663-78-2
2',3,4,4',5-PeCB...............................             123         65510-44-3  2,2',3,3',4,4',5,5',6-NoCB.......             206         40186-72-9
3,3',4,4',5-PeCB...............................             126         57465-28-8  2,2',3,3',4,4',5,5',6,6'-DeCB....             209          2051-24-3
--------------------------------------------------------------------------------------------------------------------------------------------------------
a BZ No.: Ballschmiter and Zell 1980, or International Union of Pure and Applied Chemistry (IUPAC) number.
b Chemical Abstract Service.

           Table 23-4--Elemental Compositions and Exact Masses of the Ions Monitored by High-Resolution Mass Spectrometry for PCDDs and PCDFs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                   Ion type b        Elemental       Target analyte b                                        Elemental
     Mass a                         composition                              Mass a        Ion typeb        composition           Target analyte b
--------------------------------------------------------------------------------------------------------------------------------------------------------
263.9871.......  LOCK           C5F10N............  FC43..............  383.8639.......  M              13C12H235Cl6O.....  HxCDF (S).
292.9825.......  LOCK           C7F11.............  PFK...............  385.8610.......  M+2            13C12H235Cl537ClO.  HxCDF (S).
303.9016.......  M              C12H435Cl4O.......  TeCDF.............  389.8157.......  M+2            C12H235Cl537ClO2..  HxCDD.
305.8987.......  M+2            C12H435Cl37O......  TeCDF.............  391.8127.......  M+4            C12H235Cl437Cl2O2.  HxCDD.
313.9839.......  QC             C6F12N............  FC43..............  392.9760.......  LOCK           C9F15.............  PFK.
315.9419.......  M              13C12H435Cl4O.....  TeCDF (S).........  401.8559.......  M+2            13C12H235Cl537ClO2  HxCDD (S).
316.9745.......  M+2            13C12H435Cl4O.....  TeCDF (S).........  403.8529.......  M+4            13C12H235Cl437Cl2O  HxCDD (S).
317.9389.......  M+2            13C12H435Cl337ClO.  TeCDF (S).........  425.9775.......  QC             C9F16N............  FC43.
319.8965.......  M              C12H435ClO2.......  TeCDD.............  445.7555.......  M+4            C12H235Cl637Cl2O..  OCDPE.
321.8936.......  M+2            C12H435Cl337ClO2..  TeCDD.............  407.7818.......  M+2            C12H35Cl637ClO....  HpCDF.
325.9839.......  QC             C7F12N............  FC43..............  409.7789.......  M+4            C12H35Cl537Cl2O...  HpCDF.
327.8847.......  M              C12H437Cl4O2......  TeCDD (S).........  417.8253.......  M              13C12H35Cl7O......  HpCDF (S).
330.9792.......  QC             C7F13.............  PFK...............  419.8220.......  M+2            13C12H35Cl637ClO..  HpCDF (S).
331.9368.......  M              13C12H435Cl4O2....  TeCDD (S).........  423.7766.......  M+2            C12H35Cl637ClO2...  HpCDD.
333.9339.......  M+2            13C12H435Cl37ClO2.  TeCDD (S).........  425.7737.......  M+4            C12H35Cl537Cl2O2..  HpCDD.
339.8597.......  M+2            C12H335Cl437ClO...  PeCDF.............  430.9729.......  QC             C9F17.............  PFK.
341.8567.......  M+4            C12H335Cl337Cl2O..  PeCDF.............  435.8169.......  M+2            13C12H35Cl637ClO2.  HpCDD (S).
354.9792.......  LOCK           C9F13.............  PFK...............  437.8140.......  M+4            13C12H35Cl537Cl2O2  HpCDD (S).
351.9000.......  M+2            13C12H335Cl437ClO.  PeCDF (S).........  442.9728.......  LOCK           C10F17............  PFK.
353.8970.......  M+4            13C12H335Cl3537Cl2  PeCDF (S).........  479.7165.......  M+4            C12H35Cl737Cl2O...  NCPDE.
                                 O.
355.8546.......  M+2            C12H335Cl337ClO2..  PeCDD.............  430.9729.......  LOCK           C9F17.............  PFK.
357.8516.......  M+4            C12H335Cl337Cl2O2.  PeCDD.............  441.7428.......  M+2            C1235Cl737ClO.....  OCDF.
367.8949.......  M+2            13C12H335Cl437ClO2  PeCDD (S).........  443.7399.......  M+4            C1235Cl637Cl2O....  OCDF.
369.8919.......  M+4            13C12H335Cl337Cl2O  PeCDD (S).........  457.7377.......  M+2            C1235Cl737ClO2....  OCDD.
                                 2.
375.9807.......  QC             C8F14N............  FC43..............  459.7348.......  M+4            C1235Cl637Cl2O2...  OCDD.
375.8364.......  M+2            C12H435Cl537ClO...  HxCDPE............  463.9743.......  QC             C9F18N............  FC43.
409.7974.......  M+2            C12H335Cl637ClO...  HpCPDE............  469.7779.......  M+2            13C1235Cl737ClO2..  OCDD (S).
373.8208.......  M+2            C12H235Cl537ClO...  HxCDF.............  471.7750.......  M+4            13C1235Cl637Cl2O2.  OCDD (S).
375.8178.......  M+4            C12H235Cl437Cl2O..  HxCDF.............  513.6775.......  M+4            C1235Cl837Cl2O2...  DCDPE.
375.9807.......  QC             C8F14N............  FC43..............  442.9728.......  QC             C10F17............  PFK.
--------------------------------------------------------------------------------------------------------------------------------------------------------
a The following nuclidic masses were used to calculate exact masses: H = 1.007825, C = 12.000000, 13C = 13.003355, F = 18.9984, O = 15.994915, 35Cl =
  34.968853, 37Cl = 36.965903.
b (S) = Labeled Standard. QC = Ion selected for monitoring instrument stability during the HRGC/HRMS analysis.

 Table 23-5--Elemental Compositions and Exact Masses of the Ions Monitored by High-Resolution Mass Spectrometry
                                                    for PAHs
----------------------------------------------------------------------------------------------------------------
                                                                                Elemental
        Aromatic ring No.              Mass a             Ion type b           composition       Target analyte
----------------------------------------------------------------------------------------------------------------
2................................        128.0624  M                        C10H8............  Naphthalene.
                                         130.9920  LOCK                                        PFK/FC43.
2................................        134.0828  M                        13C612C4H8.......  13C6-Naphthalene.
2................................         142.078  M                        C11H10...........  2-
                                                                                Methylnaphthalen
                                                                                e.
2................................        148.0984  M                        13C612C5H10......  13C6-2-
                                                                                Methylnaphthalen
                                                                                e.
2................................        152.0624  M                        C12H8............  Acenaphthylene.
2................................        158.0828  M                        13C612C6H8.......  13C6-
                                                                                Acenaphthylene.
2................................         154.078  M                        C12H10...........  Acenaphthene.
2................................         160.078  M                        13C612C6H10......  13C6-
                                                                                Acenaphthene.
2................................         166.078  M                        C13H10...........  Fluorene.
                                          169.988  QC                                          PFK/FC43.
2................................        172.0984  M                        13C612C7H........  13C6-Fluorene.
3................................         178.078  M                        C14H10...........  Phenanthrene.
3................................        184.0984  M                        13C6 12C8H10.....  13C6-
                                                                                Phenanthrene.
3................................         178.078  M                        C14H10...........  Anthracene.
3................................         184.078  M                        13C612C8H10......  13C6-Anthracene.
3................................         202.078  M                        C16H10...........  Fluoranthene.
                                         204.9888  QC                                          PFK.
3................................        208.0984  M                        13C612C10H10.....  13C6-
                                                                                Fluoranthene.
4................................         202.078  M                        C16H10...........  Pyrene.
4................................         205.078  M                        13C312C13H10.....  13C3-Pyrene.
                                         213.9898  QC                                          FC43.
                                         218.9856  LOCK                                        FC43.
4................................        228.0936  M                        C18H12...........  Benzo[a]anthracen
                                                                                e.
                                         230.9856  LOCK                                        PFK.
4................................         234.114  M                        13C6C12H12.......  13C6-
                                                                                Benzo[a]anthrace
                                                                                ne.
4................................        228.0936  M                        C18H12...........  Chrysene.
4................................         234.114  M                        13C612C12H12.....  13C6-Chrysene.
4................................        252.0936  M                        C20H12...........  Benzo[b]fluoranth
                                                                                ene.
4................................         258.114  M                        13C612C14H12.....  13C6-
                                                                                Benzo[b]fluorant
                                                                                hene.
4................................          252.32  M                        C20H12...........  Benzo[k]fluoranth
                                                                                ene.
4................................         258.114  M                        13C6127C14H12....  13C6-
                                                                                Benzo[k]fluorant
                                                                                hene.
5................................        252.0936  M                        C20H12...........  Benzo[e]pyrene.
5................................        256.1072  M                        13C412C16H12.....  13C4-
                                                                                Benzo[e]pyrene.
5................................        256.1072  M                        13C412C16H12.....  13C4-
                                                                                Benzo[a]pyrene.
5................................        252.0936  M                        C20H12...........  Benzo[a]pyrene.
5................................        252.0936  M                        C20H12...........  Perylene.
5................................        264.1692  M                        C20D12...........  d12-Perylene.
                                         268.9824  QC                                          PFK.
                                         263.9871  LOCK                                        FC43.
6................................        276.0936  M                        C22H12...........  Indeno[1,2,3-
                                                                                cd]pyrene.
6................................         282.114  M                        13C612C16H12.....  13C6-
                                                                                Indeno[1,2,3,cd]
                                                                                pyrene.
5................................        278.1092  M                        C22H14...........  Dibenz[a,h]anthra
                                                                                cene.
                                         280.9824  LOCK                                        PFK.
5................................        284.1296  M                        13C612C16H14.....  13C6-
                                                                                Dibenz[a,h]anthr
                                                                                acene.
6................................        276.0936  M                        C22H12...........  Benzo[g,h,i]peryl
                                                                                ene.
6................................        288.1344  M                        13C1212C10H12....  13C12-
                                                                                Benzo[g,h,i]pery
                                                                                lene.
                                         313.9839  QC                                          FC43.
----------------------------------------------------------------------------------------------------------------
a Isotopic masses used for accurate mass calculation: 1H = 1.0078, 12C = 12.0000, 13C = 13.0034, 2H = 2.0141.
b LOCK = Lock-Mass Ion PFK or FC43. QC = Quality Control Check Ion.

 Table 23-6--Elemental Compositions and Exact Masses of the Ions Monitored by High-Resolution Mass Spectrometry
                                                    for PCBs
----------------------------------------------------------------------------------------------------------------
                                                                                Elemental
      Chlorine substitution            Mass a             Ion type b           composition       Target analyte
----------------------------------------------------------------------------------------------------------------
Fn-1; Cl-1.......................        188.0393  M                        12C12H935Cl......  Cl-1 PCB
                                         190.0363  M+2                      12C12H937Cl......  Cl-1P CB
                                         200.0795  M                        13C12H935Cl......  13C12Cl-1 PCB
                                         202.0766  M+2                      12C12H937Cl......  13C12Cl-1 PCB
                                         218.9856  LOCK                     C4F9.............  PFK
Fn-2; Cl-2,3.....................        222.0003  M                        12C12H835Cl2.....  Cl-2 PCB
                                         223.9974  M+2                      12C12H835Cl37 Cl.  Cl-2 PCB
                                         225.9944  M+4                      12C12H837Cl2.....  Cl-2 PCB
                                         234.0406  M                        13C12H835Cl2.....  13C12Cl-2 PCB
                                         236.0376  M+2                      13C12H835 Cl37Cl.  13C12Cl-2 PCB
                                         242.9856  C4 F9                    C4 F9............  PFK
                                         255.9613  M                        12C12H735Cl3.....  Cl-3 PCB
                                         257.9584  M+2                      12C12H735Cl237Cl.  Cl-3 PCB
                                         268.0016  M                        13C12H735Cl3.....  13C12 Cl-3 PCB
                                         269.9986  M+2                      13C12H735Cl2 37Cl  13C12 Cl-3 PCB
Fn-3; Cl-3,4,5...................        255.9613  M                        12C12H735Cl3.....  Cl-3 PCB
                                         257.9584  M+2                      12C12H735Cl2 37Cl  Cl-3 PCB
                                         259.9554  M+4                      12C12H735Cl37Cl2.  Cl-3 PCB
                                         268.0016  M                        13C12H735Cl3.....  13C12 Cl-3 PCB
                                         269.9986  M+2                      13C12H735Cl237Cl.  13C12 Cl-3 PCB
                                         280.9825  LOCK                     C6F11............  PFK
                                         289.9224  M                        12C12H635Cl4.....  Cl-4 PCB
                                         291.9194  M+2                      12C12H635Cl337Cl.  Cl-4 PCB

                                         293.9165  M+4                      12C12H635Cl2       Cl-4 PCB
                                                                             37Cl2.
                                         301.9626  M                        13C12H635Cl4.....  13C12Cl-4 PCB
                                         303.9597  M+2                      13C12H635Cl3 37Cl  13C12Cl-4 PCB
                                         323.8834  M                        12C12H535Cl5.....  Cl-5 PCB
                                         325.8804  M+2                      12C12H535Cl4 37Cl  Cl-5 PCB
                                         327.8775  M+4                      12C12H535Cl3       Cl-5 PCB
                                                                             37Cl2.
                                         337.9207  M+2                      13C12H535Cl4 37Cl  13C12Cl-5 PCB
                                         339.9178  M+4                      13C12H535Cl3       13C12Cl-5 PCB
                                                                             37Cl2.
Fn-4; Cl-4,5,6...................        289.9224  M                        12C12H635Cl4.....  Cl-4 PCB
                                         291.9194  M+2                      12C12H635Cl3 37Cl  Cl-4 PCB
                                         293.9165  M+4                      12C12H635Cl2       Cl-4 PCB
                                                                             37Cl2.
                                         301.9626  M+2                      13C12H635Cl3 37Cl  13C12Cl-4 PCB
                                         303.9597  M+4                      13C12H635Cl2       13C12Cl-4 PCB
                                                                             37Cl2.
                                         323.8834  M                        12C12H535Cl5.....  Cl-5 PCB
                                         325.8804  M+2                      12C12H535Cl4 37Cl  Cl-5 PCB
                                         327.8775  M+4                      12C12H5 35Cl3      Cl-5 PCB
                                                                             37Cl2.
                                         330.9792  LOCK                     C7F15............  PFK
                                         337.9207  M+2                      13C12H535Cl4 37Cl  13C12Cl-5 PCB
                                         339.9178  M+4                      13C12H535Cl3       13C12Cl-5 PCB
                                                                             37Cl2.
                                         359.8415  M+2                      13C12H435Cl5.....  37Cl Cl-6 PCB
                                         361.8385  M+4                      13C12H435Cl4       Cl-6 PCB
                                                                             37Cl2.
                                         363.8356  M+6                      12C12H435Cl3       Cl-6 PCB
                                                                             37Cl3.
                                         371.8817  M+2                      13C12H435Cl5 37Cl  13C12Cl-6 PCB
                                         373.8788  M+4                      13C12H435Cl4       13C12Cl-6 PCB
                                                                             37Cl2.
Fn-5; Cl-5,6,7...................        323.8834  M                        12C12H535Cl5.....  Cl-5 PCB
                                         325.8804  M+2                      12C12H535Cl4 37Cl  Cl-5 PCB
                                         327.8775  M+4                      12C12H535Cl3       Cl-5 PCB
                                                                             37Cl2.
                                         337.9207  M+2                      13C12H535Cl4 37Cl  13C12Cl-5 PCB
                                         339.9178  M+4                      13C12H535Cl3       13C12Cl-5 PCB
                                                                             37Cl2.
                                         354.9792  LOCK                     C9F13............  PFK
                                         359.8415  M+2                      12C12H435Cl5 37Cl  Cl-6 PCB
                                         361.8385  M+4                      12C12H435Cl4       Cl-6 PCB
                                                                             37Cl2.
                                         363.8356  M+6                      12C12H435Cl3       Cl-6 PCB
                                                                             37Cl3.
                                         371.8817  M+2                      13C12H435Cl5 37Cl  13C12Cl-6 PCB
                                         373.8788  M+4                      13C12H435Cl4       13C12Cl-6 PCB
                                                                             37Cl2.
                                         393.8025  M+2                      12C12H335Cl6 37Cl  Cl-7 PCB
                                         395.7995  M+4                      12C12H335Cl5       Cl-7 PCB
                                                                             37Cl2.
                                         397.7966  M+6                      12C12H335Cl4.....  37Cl3 Cl-7 PCB
                                         405.8428  M+2                      13C12H335Cl6 37Cl  13C12Cl-7 PCB
                                         407.8398  M+4                      13C12H335Cl5       13C12Cl-7 PCB
                                                                             37Cl2.
                                         454.9728  QC                       C11F17...........  PFK
Fn-6; Cl-7,8,9,10................        393.8025  M+2                      12C12H335Cl6 37Cl  Cl-7 PCB
                                         395.7995  M+4                      12C12H335Cl5       Cl-7 PCB
                                                                             37Cl2.
                                         397.7966  M+6                      12C12H335Cl4.....  37Cl3 Cl-7 PCB
                                         405.8428  M+2                      13C12H335Cl6 37Cl  13C12Cl-7 PCB
                                         407.8398  M+4                      13C12H335Cl5       13C12Cl-7 PCB
                                                                             37Cl2.
                                         427.7635  M+2                      12C12H235Cl7 37Cl  Cl-8 PCB
                                         429.7606  M+4                      12C12H235Cl6       Cl-8 PCB
                                                                             37Cl2.
                                         431.7576  M+6                      12C12H235Cl5       Cl-8 PCB
                                                                             37Cl3.
                                         439.8038  M+2                      13C12H235Cl7 37Cl  13C12Cl-8 PCB
                                         441.8008  M+4                      13C12H235Cl6       13C12Cl-8 PCB
                                                                             37Cl2.
                                         454.9728  QC                       C11F17...........  PFK
                                         427.7635  M+2                      12C12H235Cl7 37Cl  Cl-8 PCB
                                         429.7606  M+4                      12C12H235Cl6       Cl-8 PCB
                                                                             37Cl2.
                                         431.7576  M+6                      12C12H235Cl5       Cl-8 PCB
                                                                             37Cl3.
                                         439.8038  M+2                      13C12H235Cl7 37Cl  13C12Cl-8 PCB
                                         441.8008  M+4                      13C12H235Cl6       13C12Cl-8 PCB
                                                                             37Cl2.
                                         442.9728  QC                       C10F17...........  PFK
                                         454.9728  LOCK                     C11F17...........  PFK
                                         461.7246  M+2                      12C12H135Cl8 37Cl  Cl-9 PCB
                                         463.7216  M+4                      12C12H135Cl7       Cl-9 PCB
                                                                             37Cl2.
                                         465.7187  M+6                      12C12H135Cl6       Cl-9 PCB
                                                                             37Cl3.
                                         473.7648  M+2                      13C12H135Cl8 37Cl  13C12Cl-9 PCB
                                         475.7619  M+4                      13C12H135Cl7       13C12Cl-9 PCB
                                                                             37Cl2.
                                         495.6856  M+2                      13C12H435Cl9 37Cl  Cl-10 PCB
                                         499.6797  M+4                      12C1235Cl737Cl3..  Cl-10 PCB
                                         501.6767  M+6                      12C1235Cl637Cl4..  Cl-10 PCB
                                         507.7258  M+2                      13C12H435Cl9 37Cl  13C12Cl-10 PCB
                                         509.7229  M+4                      13C12H435Cl8       13C12Cl-10 PCB
                                                                             37Cl2.
                                         511.7199  M+6                      13C12H435Cl8       13C12Cl-10 PCB
                                                                             37Cl4.
----------------------------------------------------------------------------------------------------------------
a Isotopic masses used for accurate mass calculation: 1H = 1.0078, 12C = 12.0000, 13C = 13.0034, 35Cl = 34.9689,
  37Cl = 36.9659, 19F = 18.9984. An interference with PFK m/z 223.9872 may preclude meeting 10:1 S/N for the
  DiCB congeners at optional Calibration Level 1 (Table 23-12). If this interference occurs, 10:1 S/N must be
  met at the Calibration Level 2.
b LOCK = Lock-Mass Ion PFK or FC43. QC = Quality Control Check Ion.

    Table 23-7--Composition of the Sample Fortification and Recovery Standard Solutions for PCDDs and PCDFs a
----------------------------------------------------------------------------------------------------------------
                                                                  Amount (pg/[mu]L of final      Spike recovery
                           Compound                                      extract) b                (percent)
----------------------------------------------------------------------------------------------------------------
                                        Pre-sampling Adsorbent Standards
----------------------------------------------------------------------------------------------------------------
13C12-1,2,3,4-TeCDD..........................................                             50             70-130
13C12-1,2,3,4,7-PeCDD........................................                             50             70-130
13C12-1,2,3,4,6-PeCDF........................................                             50             70-130
13C12-1,2,3,4,6,9-HxCDF......................................                             50             70-130
13C12-1,2,3,4,6,8,9-HpCDF....................................                             50             70-130
----------------------------------------------------------------------------------------------------------------
                                 Pre-extraction Filter Recovery Spike Standards
----------------------------------------------------------------------------------------------------------------
13C12-1,2,7,8-TeCDF..........................................                            100             70-130
13C12-1,2,3,4,6,8-HxCDD......................................                            100             70-130
----------------------------------------------------------------------------------------------------------------
                                            Pre-extraction Standards
----------------------------------------------------------------------------------------------------------------
13C12-2,3,7,8-TeCDD..........................................                            100             20-130
13C12-2,3,7,8-TeCDF..........................................                            100             20-130
13C12-1,2,3,7,8-PeCDD........................................                            100             20-130
13C12-1,2,3,7,8-PeCDF........................................                            100             20-130
13C12-2,3,4,7,8-PeCDF........................................                            100             20-130
13C12-1,2,3,4,7,8-HxCDD......................................                            100             20-130
13C12-1,2,3,6,7,8-HxCDD......................................                            100             20-130
13C12-1,2,3,7,8,9-HxCDD......................................                            100             20-130
13C12-1,2,3,4,7,8-HxCDF......................................                            100             20-130
13C12-1,2,3,6,7,8-HxCDF......................................                            100             20-130
13C12-2,3,4,6,7,8-HxCDF......................................                            100             20-130
13C12-1,2,3,7,8,9-HxCDF......................................                            100             20-130
13C12-1,2,3,4,6,7,8-HpCDD....................................                            100             20-130
13C12-1,2,3,4,6,7,8-HpCDF....................................                            100             20-130
13C12-1,2,3,4,7,8,9-HpCDF....................................                            100             20-130
13C12-OCDD...................................................                            200             20-130
13C12-OCDF...................................................                            200             20-130
----------------------------------------------------------------------------------------------------------------
                                             Pre-analysis Standards
----------------------------------------------------------------------------------------------------------------
13C12-1,3,6,8-TeCDD..........................................                            100            S/N>=10
13C12-1,2,3,4-TeCDF..........................................                            100            S/N>=10
13C12-1,2,3,4,6,7-HxCDD......................................                            100            S/N>=10
13C12-1,2,3,4,6,7,9-HpCDD....................................                            100            S/N>=10
----------------------------------------------------------------------------------------------------------------
                                          Alternate Recovery Standards
----------------------------------------------------------------------------------------------------------------
13C12-1,3,7,8-TeCDD..........................................                            100             20-130
13C12-1,2,4,7,8-PeCDD........................................                            100             20-130
----------------------------------------------------------------------------------------------------------------
a Changes in the amounts of spike standards added to the sample or its representative extract will necessitate
  an adjustment of the calibration solutions to prevent the introduction of inconsistencies. Spike concentration
  assumes 1[mu]L sample injection volume for analysis.
b Spike levels assume half of the extract will be archived before cleanup. Spike levels may be adjusted for
  different split levels.

         Table 23-8--Composition of the Sample Fortification and Recovery Standard Solutions for PAHs a
----------------------------------------------------------------------------------------------------------------
                                                                  Amount (pg/[mu]L of final      Spike recovery
                           Compound                                      extract) b                (percent)
----------------------------------------------------------------------------------------------------------------
                                        Pre-sampling Adsorbent Standards
----------------------------------------------------------------------------------------------------------------
13C6-Benzo[c]fluorene........................................                            100             70-130
13C12-Benzo[j]fluoranthene...................................                            100             70-130
----------------------------------------------------------------------------------------------------------------
                                 Pre-extraction Filter Recovery Spike Standards
----------------------------------------------------------------------------------------------------------------
d10-Anthracene...............................................                            100             70-130
----------------------------------------------------------------------------------------------------------------
                                            Pre-extraction Standards
----------------------------------------------------------------------------------------------------------------
13C6-Naphthalene.............................................                            100             20-130
13C6-2-Methylnaphthalene.....................................                            100             20-130
13C6-Acenaphthylene..........................................                            100             20-130
13C6-Acenaphthene............................................                            100             20-130
13C6-Fluorene................................................                            100             20-130
13C6-Phenanthrene............................................                            100             20-130
13C6-Anthracene..............................................                            100             20-130
13C6-Fluoranthene............................................                            100             20-130
13C3-Pyrene..................................................                            100             20-130
13C6-Benzo[a]anthracene......................................                            100             20-130
13C6-13Chrysene..............................................                            100             20-130
13C6-Benzo[b]fluoranthene....................................                            100             20-130

13C6-Benzo[k]fluoranthene....................................                            100             20-130
13C4-Benzo[e]pyrene..........................................                            100             20-130
13C4-Benzo[a]pyrene..........................................                            100             20-130
d12-Perylene.................................................                            100             20-130
13C6-Indeno[1,2,3-cd]pyrene..................................                            100             20-130
13C6-Dibenz[a,h]anthracene...................................                            100             20-130
13C12-Benzo[g,h,i]perylene...................................                            100             20-150
----------------------------------------------------------------------------------------------------------------
                                             Pre-analysis Standards
----------------------------------------------------------------------------------------------------------------
d10-Acenaphthene.............................................                            100            S/N>=10
d10-Pyrene...................................................                            100            S/N>=10
d12-Benzo[e]pyrene...........................................                            100            S/N>=10
----------------------------------------------------------------------------------------------------------------
a Changes in the amounts of spike standards added to the sample or its representative extract will necessitate
  an adjustment of the calibration solutions to prevent the introduction of inconsistencies.
b Spike levels assume half of the extract will be archived before cleanup. You may adjust spike levels for
  different split levels.

        Table 23-9--Composition of the Sample Fortification and Recovery Standard Solutions for PCBs \a\
----------------------------------------------------------------------------------------------------------------
                                                                Amount  (pg/[micro]L of final   Spike  recovery
              Compound                       BZ  No.\b\                 extract) \c\               (percent)
----------------------------------------------------------------------------------------------------------------
                                        Pre-sampling Adsorbent Standards
----------------------------------------------------------------------------------------------------------------
13C12-3,3'-DiCB.....................  11L                                                100             70-130
13C12-2,4',5-TrCB...................  31L                                                100             70-130
13C12-2,2',3,5',6-PeCB..............  95L                                                100             70-130
13C12-2,2',4,4',5,5'-HxCB...........  153L                                               100             70-130
----------------------------------------------------------------------------------------------------------------
                                 Pre-extraction Filter Recovery Spike Standards
----------------------------------------------------------------------------------------------------------------
13C12-2,3,3',4,5,5'-HxCB............  159L                                               100             70-130
----------------------------------------------------------------------------------------------------------------
                                            Pre-extraction Standards
----------------------------------------------------------------------------------------------------------------
13C12-2-MoCB (WDC)..................  1L                                                 100             20-145
13C12-4-MoCB (WDC)..................  3L                                                 100             20-145
13C12-2,2'-DiCB (WDC)...............  4L                                                 100             20-145
13C12-4,4'-DiCB (WDC)...............  15L                                                100             20-145
13C12-2,2',6-TrCB (WDC).............  19L                                                100             20-145
13C12-3,4',4'-TrCB (WDC)............  37L                                                100             20-145
13C12-2,2',6,6'-TeCB (WDC)..........  54L                                                100             20-145
13C12-3,3',4,4'-TeCB (WDC) (WHOT)     77L                                                100             20-145
 (NOAAT).
13C12-3,4,4',5-TeCB (WHOT)..........  81L                                                100             20-145
13C12-2,2',4,6,6'-PeCB (WDC)........  104L                                               100             20-145
13C12-2,3,3',4,4'-PeCB (WHOT).......  105L                                               100             20-145
13C12-2,3,4,4',5-PeCB (WHO).........  114L                                               100             20-145
13C12-2,3',4,4',5-PeCB (WHOT).......  118L                                               100             20-145
13C12-2',3,4,4',5-PeCB (WHOT).......  123L                                               100             20-145
13C12-3,3',4,4',5-PeCB (WDC) (WHOT).  126L                                               100             20-145
13C12-2,2',4,4',6,6'-HxCB (WDC).....  155L                                               100             20-145
13C12-2,3,3',4,4',5-HxCB (WHOT).....  156L                                               100             20-145
13C12-2,3,3',4,4',5'-HxCB (WHOT)....  157L                                               100             20-145
13C12-2,3',4,4',5,5'-HxCB (WHOT)....  167L                                               100             20-145
13C12-3,3',4,4',5,5'-HxCB (WDC)       169L                                               100             20-145
 (WHOT) (NOAAT).
13C12-2,2',3,3',4,4',5'-HpCB (NOAAT)  170L                                               100             20-145
13C12-2,2',3,4,4',5,5'-HpCB (NOAAT).  180L                                               100             20-145
13C12-2,2',3,4',5,6,6'-HpCB (WDC)...  188L                                               100             20-145
13C12-2,3,3',4,4',5,5'-HpCB (WDC)     189L                                               100             20-145
 (WHOT).
13C12-2,2',3',3',5,5',6,6'-OcCB       202L                                               100             20-145
 (WDC).
13C12-2,3',3',4,4',5,5',6-OcCB (WDC)  205L                                               100             20-145
13C12-2,2',3,3',4,4',5,5',6-NoCB      206L                                               100             20-145
 (WDC).
13C12-2,2',3,3',4,5,5',6,6'-NoCB      208L                                               100             20-145
 (WDC).
13C12-DeCB (WDC)....................  209L                                               100             20-145
----------------------------------------------------------------------------------------------------------------
                                             Pre-analysis Standards
----------------------------------------------------------------------------------------------------------------
13C12-2,5-DiCB......................  9L                                                 100            S/N>=10
13C12-2,2',5,5'-TeCB (NOAAT)........  52L                                                100            S/N>=10

13C12-2,2',4,5,5'-PeCBl (NOAAT).....  101L                                               100            S/N>=10
13C12-2,2',3,4,4',5'-HxCB (NOAAT)...  138L                                               100            S/N>=10
13C12-2,2',3,3',4,4',5,5'-OcCB......  194L                                               100            S/N>=10
----------------------------------------------------------------------------------------------------------------
                                       Optional Cleanup Spiking Standards
----------------------------------------------------------------------------------------------------------------
13C12-2-MoCB (NOAAT)................  28L                                                100             20-130
13C12-2,2',4,5,5'-PeCB..............  111L                                               100             20-130
13C12-2,2',3,3',5,5',6,6'-OcCB......  178L                                               100             20-130
----------------------------------------------------------------------------------------------------------------
                                          Alternate Recovery Standards
----------------------------------------------------------------------------------------------------------------
\13\C12-2,3',4',5-TeCB..............  70L                                                100             20-130
13C12-2,3,4,4'-TeCB.................  60L                                                100             20-130
13C12-3,3',4,5,5'-PeCB..............  127L                                               100             20-130
----------------------------------------------------------------------------------------------------------------
\a\ Changes in the amounts of spike standards added to the sample or its representative extract will necessitate
  an adjustment of the calibration solutions to prevent the introduction of inconsistencies.
\b\ BZ No.: Ballschmiter and Zell 1980, or IUPAC number.
\c\ Spike levels assume half of the extract will be archived before cleanup. Spike levels may be adjusted for
  different split levels.

                      Table 23-10--Sample Storage Conditions a and Laboratory Hold Times b
----------------------------------------------------------------------------------------------------------------
           Sample type                 PCDD/PCDF               PAH                           PCB
----------------------------------------------------------------------------------------------------------------
                                      Field Storage and Shipping Conditions
----------------------------------------------------------------------------------------------------------------
All Field Samples...............  <=20  5  <=20  5  <=20  5 [deg]C, (68
                                   [deg]C, (68  9 [deg]F).
                                   minus> 9 [deg]F).    minus> 9 [deg]F).
----------------------------------------------------------------------------------------------------------------
                                          Laboratory Storage Conditions
----------------------------------------------------------------------------------------------------------------
Sampling Train Rinses and         <=6 [deg]C (43       <=6 [deg]C (43       <=6 [deg]C (43 [deg]F).
 Filters.                          [deg]F).             [deg]F).
Adsorbent.......................  <=6 [deg]C (43       <=6 [deg]C (43       <=6 [deg]C (43 [deg]F).
                                   [deg]F).             [deg]F).
Extract and Archive.............  <-10 [deg]C (14      <-10 [deg]C (14      <-10 [deg]C (14 [deg]F).
                                   [deg]F).             [deg]F).
----------------------------------------------------------------------------------------------------------------
                                              Laboratory Hold Times
----------------------------------------------------------------------------------------------------------------
Extract and Archive.............  One year...........  45 Days............  One year.
----------------------------------------------------------------------------------------------------------------
\a\ All samples must be stored in the dark.
\b\ Hold times begin from the time the laboratory receives the samples.

                              Table 23-11--Composition of the Initial Calibration Standard Solutions for PCDDs and PCDFs a
                                                                      [pg/[micro]L]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Cal 1                                                                         Cal 7
                      Standard compound                         (optional)     Cal 2        Cal 3        Cal 4        Cal 5        Cal 6      (optional)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Target (Unlabeled) Analytes..................................         0.50          1.0          5.0         10.0           25           50          100
Pre-sampling Adsorbent Standards.............................           50           50           50           50           50           50           50
Pre-extraction Filter Recovery Standards.....................           50           50           50           50           50           50           50
Pre-extraction Standards.....................................           50           50           50           50           50           50           50
Pre-analysis Standards.......................................           50           50           50           50           50           50           50
Alternate Recovery Standards.................................           50           50           50           50           50           50           50
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Assumes 1 [micro]L injection volume.

                                    Table 23-12--Composition of the Initial Calibration Standard Solutions for PAHs a
                                                                       [pg/[mu]L]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Cal 1                                                                         Cal 7
                      Standard compound                         (optional)     Cal 2        Cal 3        Cal 4        Cal 5        Cal 6      (optional)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Target (Unlabeled) Analytes..................................            1            2            4           20           80          400        1,000
Pre-sampling Adsorbent Standards.............................          100          100          100          100          100          100          100
Pre-extraction Filter Recovery Standards.....................          100          100          100          100          100          100          100
Pre-extraction Standards.....................................          100          100          100          100          100          100          100
Pre-analysis Standards.......................................          100          100          100          100          100          100          100
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Assumes 1 [micro]L injection volume.

                                    Table 23-13--Composition of the Initial Calibration Standard Solutions for PCBs a
                                                                       [pg/[mu]L]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Cal 1                                                                         Cal 7
                      Standard compound                         (optional)     Cal 2        Cal 3        Cal 4        Cal 5        Cal 6      (optional)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Target (Unlabeled) Analytes..................................         0.50            1            5           10           50          400        2,000
Pre-sampling Adsorbent Standard(s)...........................          100          100          100          100          100          100          100
Pre-extraction Filter Recovery Standards.....................          100          100          100          100          100          100          100
Pre-extraction Standards.....................................          100          100          100          100          100          100          100
Pre-analysis Standards.......................................          100          100          100          100          100          100          100
Alternate Standards..........................................          100          100          100          100          100          100          100
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Assumes 1 [micro]L injection volume.

  Table 23-14--Minimum Requirements for Initial and Daily Calibration Response Factors for Isotopically Labeled
                                              and Native Compounds
----------------------------------------------------------------------------------------------------------------
                                                                            Relative response factors
                                                               -------------------------------------------------
                         Analyte group                                                     Daily and continuing
                                                                  Initial calibration     calibration  (percent
                                                                          RSD                  difference)
----------------------------------------------------------------------------------------------------------------
Native (Unlabeled) Analytes...................................                      10                       25
Pre-sampling Adsorbent Standard(s)............................                      20                       25
Pre-extraction Filter Recovery Standards......................                      20                       25
Pre-extraction Standards......................................                      20                       30
Pre-analysis Standards........................................                      20                       30
Alternative Recovery Standards................................                      20                       30
----------------------------------------------------------------------------------------------------------------

                      Table 23-15--Recommended Ion Type and Acceptable Ion Abundance Ratios
----------------------------------------------------------------------------------------------------------------
                                                                                Control limits
        No. of chlorine atoms                   Ion type            Theoretical  ----------------      Upper
                                                                       ratio           Lower
----------------------------------------------------------------------------------------------------------------
1....................................  M/M+2                                3.13            2.66            3.60
2....................................  M/M+2                                1.56            1.33            1.79
3....................................  M/M+2                                1.04            0.88            1.20
4....................................  M/M+2                                0.77            0.65            0.89
5....................................  M+2/M+4                              1.55            1.32            1.78
6....................................  M+2/M+4                              1.24            1.05            1.43
6 \a\................................  M/M+2                                0.51            0.43            0.59
7....................................  M+2/M+4                              1.05            0.89            1.21
7 \b\................................  M/M+2                                0.44            0.37            0.51
8....................................  M+2/M+4                              0.89            0.76            1.02
9....................................  M+2/M+4                              0.77            0.65            0.89
10...................................  M+4/M+6                              1.16            0.99            1.33
----------------------------------------------------------------------------------------------------------------
\a\ Used only for 13C-HxCDF.
\b\ Used only for 13C-HpCDF.

                                  Table 23-16--Typical DB5-MS Column Conditions
----------------------------------------------------------------------------------------------------------------
                                                                      Analyte
         Column parameter         ------------------------------------------------------------------------------
                                           PCDD/PCDF                     PAH                       PCB
----------------------------------------------------------------------------------------------------------------
Injector temperature.............  250 [deg]C...............  320 [deg]C..............  270 [deg]C.
Initial oven temperature.........  100 [deg]C...............  100 [deg]C..............  100 [deg]C.
Initial hold time (minutes)......  2........................  2.......................  2.
Temperature program..............  100 to 190 [deg]C at 40    100 to 300 [deg]C at      100 to 150 [deg]C at 15
                                    [deg]C/min, then 190 to    8[deg]C/min.              [deg]C/min, then 150 to
                                    300 [deg]C at 3[deg]C/                               290 [deg]C at 2.5
                                    min.                                                 [deg]C/min.
----------------------------------------------------------------------------------------------------------------

              Table 23-17--Assignment of Pre-extraction Standards for Quantitation of Target PCBs b
----------------------------------------------------------------------------------------------------------------
            PCB congener                    BZ No. \a\              Labeled analog                BZ No.
----------------------------------------------------------------------------------------------------------------
2,4'-DiCB (NOAAT)..................  8                        13C12-2,2'-DiCB...........  4L
2,2',5-TrCB (NOAAT)................  18                       13C12-2,2',6-TrCB.........  19L
2,4,4'-TrCB (NOAAT)................  28                       13C12-2,2',6-TrCB.........  19L
2,2',3,5'-TeCB (NOAAT).............  52                       13C12-2,2',6,6'-TeCB......  54L

2,2',5,5'-TeCB (NOAAT).............  52                       13C12-2,2',6,6'-TeCB......  54L
2,3',4,4'-TeCB (NOAAT).............  66                       13C12-2,2',6,6'-TeCB......  54L
3,3',4,4'-TeCB (NOAAT) (WHOT)......  77                       13C12-3,3',4,4'-TeCB......  77L
3,4,4',5-TeCB (WHOT)...............  81                       13C12-3,4,4'',5-TeCB......  81L
2,2',4,5,5'-PeCB (NOAAT)...........  101                      13C12-2,2',4,5,5'-PeCB....  104L
2,3,3',4,4'-PeCB (NOAAT) (WHOT)....  105                      13C12-2,3,3',4,4'-PeCB....  105L
2,3,4,4',5-PeCB (WHOT).............  114                      13C12-2,3,4,4',5-PeCB.....  114L
2,3',4,4',5-PeCB (WHOT)............  118                      13C12-2,3',4,4',5-PeCB....  118L
2',3,4,4',5-PeCB (WHOT)............  123                      13C12-2',3,4,4',5-PeCB....  123L
3,3',4,4',5-PeCB (NOAAT) (WHOT)....  126                      13C12-3,3',4,4',5-PeCB....  126L
2,2',3,3',4,4'-HxCB (NOAAT)........  128                      13C12-2,2',4,4',6,6'-HxCB.  155L
2,2',3,4,4',5'-HxCB (NOAAT)........  138                      13C12-2,2', 4,4',6,6'-HxCB  155L
2,2',4,4',5,5'-HxCB (NOAAT)........  153                      13C12-2,2', 4,4',6,6'-HxCB  155L
2,3,3',4,4',5-HxCB (WHOT)..........  156                      13C12-2,3,3',4,4',5-HxCB..  156L
2,3,3',4,4',5'-HxCB (WHOT).........  157                      13C12-2,3,3',4,4',5'-HxCB.  157L
2,3',4,4',5,5'-HxCB (WHOT).........  167                      13C12-2,3',4,4',5,5'-HxCB.  167L
3,3',4,4',5,5'-HxCB (NOAAT) (WHOT).  169                      13C12-3,3',4,4',5,5'-HxCB.  169L
2,2',3,3',4,4',5-HpCB (NOAA).......  170                      13C12-2,2',3,3',4,4',5'-    170L
                                                               HpCB.
2,2',3,4,4',5,5'-HpCB (NOAAT)......  180                      13C12-2,2',3,4,4',5,5'-     180L
                                                               HpCB.
2,2',3,4',5,5',6-HpCB (NOAAT)......  187                      13C12-2,2',3,4',5,6,6'-     188L
                                                               HpCB.
2,3,3',4,4',5,5'-HpCB (WHOT).......  189                      13C12-2,3,3',4,4',5,5'-     189L
                                                               HpCB.
2,2',3,3',4,4',5,6-OcCB (NOAAT)....  195                      13C12-2,2' 3,3',5,5',6,6'-  202L
                                                               OcCB.
2,2',3,3',4,4',5,5',6-NoCB (NOAAT).  206                      13C12-                      206L
                                                               2,2',3,3',4,4',5,5',6-
                                                               NoCB.
2,2',3,3',4,4',5,5',6,6'-DeCB        209                      13C12-DeCB................  209L
 (NOAAT).
----------------------------------------------------------------------------------------------------------------
\a\ BZ No.: Ballschmiter and Zell 1980, or IUPAC number.
\b\ Assignments assume the use of the SPB-Octyl column. In the event you choose another column, you may select
  the labeled standard having the same number of chlorine substituents and the closest retention time to the
  target analyte in question as the labeled standard to use for quantitation.

   Table 23-18--Estimated Method Detection Limits for PCDDs and PCDFs
------------------------------------------------------------------------
                                     MDL \a\  (ng/       TEQ-DL  (ng/
             Target                     sample)             sample)
------------------------------------------------------------------------
Total OCDD......................           1.75E-01            5.00E-05
Total OCDF......................           5.38E-02            1.51E-05
1,2,3,4,6,7,8-HpCDD.............           2.36E-02            2.16E-04
1,2,3,4,6,7,8-HpCDF.............           4.88E-02            4.82E-04
1,2,3,4,7,8-HxCDD...............           9.26E-03            8.50E-04
1,2,3,4,7,8-HxCDF...............           6.60E-02            6.48E-03
1,2,3,4,7,8,9-HpCDF.............           2.46E-02            2.40E-04
1,2,3,6,7,8-HxCDD...............           1.06E-02            9.86E-04
1,2,3,6,7,8-HxCDF...............           7.72E-03            7.06E-04
1,2,3,7,8-PeCDD.................           3.52E-02            3.46E-02
1,2,3,7,8-PeCDF.................           1.46E-02            4.20E-04
1,2,3,7,8,9-HxCDD...............           2.70E-02            2.60E-03
1,2,3,7,8,9-HxCDF...............           6.24E-03            5.54E-04
2,3,4,6,7,8-HxCDF...............           1.88E-02            1.82E-03
2,3,4,7,8-PeCDF.................           1.29E-02            3.70E-03
2,3,7,8-TeCDD...................           2.70E-02            2.68E-02
2,3,7,8-TeCDF...................           1.80E-02            1.75E-03
    Mean DL.....................           2.34E-02            5.48E-03
    Sum of DL...................           2.90E-01            4.11E-02
------------------------------------------------------------------------
\a\ Detection Limits are based on a survey of laboratories MDL data from
  Information Collection Requests from the Industrial Boiler and Utility
  MACT rulemaking process. MDL assumes half of the sample was archived
  before concentration.

             Table 23-19--Target Detection Limits for PAHs a
------------------------------------------------------------------------
                       Target                          MDL  (ng/sample)
------------------------------------------------------------------------
Naphthalene.........................................              110.5
2-Methylnaphthalene.................................               36.3
Acenaphthylene......................................               31.4
Acenaphthene........................................               11.3
Fluorene............................................               12.8
Phenanthrene........................................               19.9
Anthracene..........................................               11.8
Fluoranthene........................................                9.0
Pyrene..............................................                7.6
Benzo[a]anthracene..................................                6.2

Chrysene............................................                6.2
Benzo[b]fluoranthene................................                7.8
Benzo[k]fluoranthene................................                6.4
Benzo[e]pyrene......................................                3.3
Benzo[a]pyrene......................................               15.9
Perylene............................................               28.3
Indeno[1,2,3-cd]pyrene..............................                7.2
Dibenz[a,h]anthracene...............................                6.8
Benzo[g,h,i]perylene................................                6.8
    Mean DL.........................................                 23
    Sum of DL.......................................                435
------------------------------------------------------------------------
\a\ Detection limits are based on a survey of laboratories MDL data from
  Information Collection Requests form the Coke Oven and Electric Power
  Generating unit MACT rulemaking process.

        Table 23-20--Estimated Method Detection Limits for PCBs a
------------------------------------------------------------------------
                                                              Target
                                                             detection
                 Target                       BZ No.        limit  (pg/
                                                              sample)
------------------------------------------------------------------------
2,4'-DiCB...............................               8              30
2,2',5-TrCB.............................              18              32
2,4,4'-TrCB.............................              28              44
2,2',3,5'-TeCB..........................              44              80
2,2',5,5'-TeCB..........................              52              30
2,3',4,4'-TeCB..........................              66              34
3,3',4,4'-TeCB..........................              77              28
3,4,4',5-TeCB...........................              81              36
2,2',4,5,5'-PeCB........................             101              94
2,3,3',4,4'-PeCB........................             105              34
2,3,4,4',5-PeCB.........................             114              30
2,3',4,4',5-PeCB........................             118              60
2',3,4,4',5-PeCB........................             123              34
3,3',4,4',5-PeCB........................             126              32
2,2',3,3',4,4'-HxCB.....................             128              58
2,2',3,4,4',5'-HxCB.....................             138              72
2,2',4,4',5,5'-HxCB.....................             153              60
2,3,3',4,4',5-HxCB......................             156              46
2,3,3',4,4',5'-HxCB.....................             157              46
2,3',4,4',5,5'-HxCB.....................             167              26
3,3',4,4',5,5'-HxCB.....................             169              30
2,2',3,3',4,4',5-HpCB...................             170              24
2,2',3,4,4',5,5'-HpCB...................             180              60
2,2',3,4',5,5',6-HpCB...................             187              34
2,3,3',4,4',5,5'-HpCB...................             189              26
2,2',3,3',4,4',5,6-OcCB.................             195              44
2,2',3,3',4,4',5,5',6-NoCB..............             206              32
2,2',3,3',4,4',5,5',6,6'-DeCB...........             209              32
    Mean DL.............................  ..............              42
    Sum of DL...........................  ..............           1,188
------------------------------------------------------------------------
\a\ Detection Limits are based on information from EPA Method 1668C,
  assuming half of the sample extract is archived before concentration.

BILLING CODE 6560-50-P

[GRAPHIC] [TIFF OMITTED] TP14JA20.011

[GRAPHIC] [TIFF OMITTED] TP14JA20.012

[GRAPHIC] [TIFF OMITTED] TP14JA20.013

[GRAPHIC] [TIFF OMITTED] TP14JA20.014

BILLING CODE 6560-50-P

Appendix A to Method 23

                   Complete List of 209 PCB Congeners and Their Isomers With Corresponding Isotope Dilution Quantitation Standards \a\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                  Unlabeled  target                   Pre-extraction                    Unlabeled  target
    Pre-extraction  standard       BZ \b\  No.         analyte        BZ \b\  No.        standard        BZ \b\  No.         analyte         BZ \b\ No.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                       MoCBs                      DiCBs
--------------------------------------------------------------------------------------------------------------------------------------------------------
13C12-2-MoCB....................  1L             2-MoCB............  1              13C12-2,2'-DiCB...  4L             2,2'-DiCB.........  4
13C12-2-MoCB....................  1L             3-MoCB............  2              13C12-2,2'-DiCB...  4L             2,3-DiCB..........  5
13C12-4-MoCB....................  3L             4-MoCB............  3              13C12-2,2'-DiCB...  4L             2,3'-DiCB.........  6
                                                                                13C12-2,2'-DiCB...  4L             2,4-DiCB..........  7
                                                                                13C12-2,2'-DiCB...  4L             2,4'-DiCB.........  8
                                                                                13C12-2,2'-DiCB...  4L             2,5-DiCB..........  9