Mefhoc 1624 evision S
VOLATILE ORGANIC
ISOTOPE DILUTION
Method 1625 Revision B
SEMIVOLATILE ORGANIC COMPOUNDS BY
SOTOPE DILUTION GC 'MS
Em
wiiiv'*-- V Jr. >¦? ji
Industrial Technology Division
:Y WASHINGTON, D.C. 20460
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Introduction
Methods 1624 and 1625 were developed by the Industrial
Technology Division (ITD) within EPA's Office of Water to
provide improved precision and accuracy of analysis of
pollutants in water The ITD is responsible for development
and promulgation of nationwide standards setting limits on
pollutant levels in industrial discharges
Methods 1624 and 1625 are isotope dilution, gas
chromatrography-mass spectrometry methods for analysis
of the volatile and semi-volatile, organic "priority"
pollutants, and other organic pollutants listed in the
Consent Decree [National Resources Defense Council,
Inc , et al v Train, 8 ERC 2120 (D D.C 1976)] Isotope
dilution is a technique which employs stable, isotopically
labeled analogs of the compounds of interest as internal
standards in the analysis
Revisions B of Methods 1624 and 1625 were proposed in
the Federal Register on October 26, 1984 (49 FR 43234)
under the authority of section 304(h) of the Clean Water
Act, and are expected to be promulgated as final regula-
tions in early 1985
Questions concerning the Methods or their application
should be addressed to W A Telliard, Industrial
Technology Division (WH-552), USEPA, 401 M St SW,
Washington, DC 20460 (202-382-7131)
Publication date: January 1985
i
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Method 1624 Revision B
VOLATILE ORGANIC COMPOUNDS BY ISOTOPE DILUTION GC/MS
1 SCOPE AND APPLICATION
1 1 This method is designed to determine the volatile 1 4
toxic organic pollutants associated with the 1976
Consent Decree and additional compounds
amenable to purge and trap gas chromatography-
mass spectrometry (GC/MS)
1 2 The chemical compounds listed in table 1 may be
determined in municipal and industrial discharges by
this method The method is designed to meet the 2
survey requirements of EPA's Industrial Technology 2 1
Division (ITD) and the National Pollutants Discharge
Elimination System (NPDES) under 40 CFR 136 1
and 136 5 Any modifications of this method, beyond
those expressly permitted, shall be considered as
major modifications subject to application and ap-
proval of alternate test procedures under 40 CFR
136 4 and 136 5
1 3 The detection limit of this method is usually depen-
dent on the level of interferences rather than in-
strumental limitations The limits in table 2 represent
the minimum quantity that can be detected with no in-
terferences present
TABLE 1
Volatile Organic Compounds Analyzed by Isotope Dilution GCMS
POLLUTANT LABELED COMPOUND
COMPOUND
STORET
CAS
EGD
NPDES
ANALOG CAS
EGD
acetone
81552
67-64-1
516 V
de
666-52-4
616
V
acrolein
34210
107-02-8
002 V
001
V
d<
33984-05-3
202
V
acrylonitnle
34215
107-13-1
003 V
002
V
d3
53807-26-4
203
V
benzene
34030
71-43-2
004 V
003
V
de
1076-43-3
204
V
bromodichloromethane
32101
75-27-4
048 V
012
V
,3C
93952-10-4
248
V
bromoform
32104
75-25-2
047 V
005
V
,3C
72802-81-4
247
V
bromomethane
34413
74-83-9
046 V
020
V
d3
1111 -88-2
246
V
carbon tetrachloride
32102
56-23-5
006 V
006
V
,3C
32488-50-9
206
V
chlorobenzene
34301
108-90-7
007 V
007
V
d5
3114-55-4
207
V
chloroethane
34311
75-00-3
016 V
009
V
d5
19199-91-8
216
V
2-chloroethylvinyl ether
34576
110-75-8
019 V
010
V
Chloroform
32106
67-66-3
023 V
011
V
,3C
31717-44-9
223
V
chloromethane
34418
74-87-3
045 V
021
V
d3
1111 -89-3
245
V
dibromochloromethane
32105
124-48-1
051 V
008
V
,3C
93951-99-6
251
V
1 1-dichloroethane
34496
75-34-3
013 V
014
V
d3
56912-77-7
213
V
1,2-dichloroethane
32103
107-06-2
010 V
015
V
d<
1 7070-07-0
210
V
1,1-dichloroethene
34501
75-35-4
029 V
016
V
d2
22280-73-5
229
V
trans-1,2-dichlorethene
34546
156-60-5
030 V
026
V
d3
42366-47-2
230
V
1,2-dichloropropane
34541
78-87-5
032 V
017
V
de
93952-08-0
232
V
trans-1,3-dichloropropene
34699
10061-02-6
033 V
d4
93951-86-1
233
V
diethyl elher
81576
60-29-7
515 V
dio
2679-89-2
615
V
p-dioxane
81582
123-91-1
527 V
de
1 7647-74-4
627
V
ethylbenzene
34371
100-41-4
038 V
019
V
dio
25837-05-2
238
V
methylene chloride
34423
75-09-2
044 V
022
V
d2
1665-00-5
244
V
methyl ethyl ketone
81595
78-93-3
514 V
d3
53389-26-7
614
V
1.1,2,2-tetrachloroelhane
34516
79-34-5
015 V
023
V
dj
33685-54-0
215
V
tetrachlorethene
34475
127-18-4
085 V
024
V
,3C2
32488-49-6
285
V
toluene
34010
108-88-3
086 V
025
V
de
2037-26-5
286
V
1,1,1-lrichloroethane
34506
71-55-6
011 V
027
V
d3
2747-58-2
211
V
1.1,2-lrichloroethane
34511
79-00-5
014 V
028
V
,3C2
93952-09-1
214
V
trichloroethene
39180
79-01-6
087 V
029
V
,3c2
93952-00-2
287
V
vinyl chloride
39175
75-01-4
088 V
031
V
d3
6745-35-3
288
V
The GC/MS portions of this method are for use only
by analysts experienced with GC/MS or under the
close supervision of such qualified persons
Laboratories unfamiliar with the analyses of en-
vironmental samples by GC/MS should run the per-
formance tests in reference 1 before beginning
SUMMARY OF METHOD
Stable isotopically labeled analogs of the com-
pounds of interest are added to a 5 mL water sample
The sample is purged at 20-25 °C with an inert gas in
a specially designed chamber The volatile organic
compounds are transferred from the aqueous phase
into the gaseous phase where they are passed into a
sorbent column and trapped After purging is com-
pleted, the trap is backflushed and heated rapidly to
desorb the compounds into a gas chromatograph
(GC) The compounds are separated by the GC and
detected by a mass spectrometer (MS) (references 2
and 3) The labeled compounds serve to correct the
variability of the analytical technique
1
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TABLE 2
Gas Chromatography of Purgeable Organic Compounds by Isotope Dilution GC/MS
EGD
REF
MEAN
MINIMUM
NO
EGD
RETENTION
LEVEL (2)
(D
COMPOUND
NO
TIME (SEC)
(MQ/L)
181
bromochloromethane (internal slandard)
181
730
10
245
chloromethane-d3
181
147
50
345
chloromethane
245
148
50
246
bromomethane-dj
181
243
50
346
bromomethane
246
246
50
288
vinyl chloride-ds
181
301
50
388
vinyl chloride
288
304
50
216
chioroetnane-ds
181
378
50
316
chloroethane
216
386
50
244
methylene chlonde-d2
181
512
10
344
methylene chloride
244
517
10
616
acetone-ds
181
554
50
716
acetone
616
565
50
002
acrolein
181
566
50
203
acrylonitnle-da
181
606
50
303
acrylonitrile
203
612
50
229
l,l-dichloroethene-d2
181
696
10
329
1,1-dichloroethene
229
696
10
213
l,l-dichloroethane-d3
181
¦ 778
10
313
1,1-dichloroethane
213
786
10
615
diethyl ether-d10
181
804
50
715
diethyl elher
615
820
50
230
trans-1,2-dichloroethene-
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2 2 Identification of a compound (qualitative analysis) is
performed by comparing the GC retention time and
the background corrected characteristic spectral
masses with those of authentic standards
2 3 Quantitative analysis is performed by GC/MS using
extracted ion current profile (EICP) areas Isotope
dilution is used when labeled compounds are
available, otherwise, an internal or external standard
method is used
2 4 Quality is assured through reproducible calibration
and testing of the purge and trap and GC/MS
systems
3 CONTAMINATION AND INTERFERENCES
3 1 Impurities in the purge gas, organic compounds out-
gassing from the plumbing upstream of the trap, and
solvent vapors in the laboratory account for the
majority of contamination problems The analytical
system is demonstrated to be free from interferences
under conditions of the analysis by analyzing blanks
initially and with each sample lot (samples analyzed
on the same 8 hr shift), as described in section 8 5
3 2 Samples can be contaminated by diffusion of volatile
organic compounds (particularly methylene chloride)
through the bottle seal during shipment and storage
A field blank prepared from reagent water and
carried through the sampling and handling protocol
serves as a check on such contamination
3 3 Contamination by carry-over can occur when high
level and low level samples are analyzed sequen-
tially To reduce carry-over, the purging device and
sample syringe are rinsed between samples with
reagent water When an unusually concentrated
sample is encountered, it is followed by analysis of a
reagent water blank to check for carry-over For
samples containing large amounts of water soluble
materials, suspended solids, high boiling com-
pounds, or high levels of purgeable compounds, the
purge device is washed with soap solution, rinsed
with tap and distilled water, and dried in an oven at
100-125 °C The trap and other parts of the system
are also subject to contamination, therefore, frequent
bakeout and purging of the entire system may be
required
3 4 Interferences resulting from samples will vary con-
siderably from source to source, depending on the
diversity of the industrial complex or municipality
being sampled
4 SAFETY
4 1 The toxicity or carcinogenicity of each compound or
reagent used in this method has not been precisely
determined, however, each chemical compound
should be treated as a potential health hazard
Exposure to these compounds should be reduced to
the lowest possible level The laboratory is responsi-
ble for maintaining a current awareness file of OSHA
regulations regarding the safe handling of the
chemicals specified in this method A reference file
of data handling sheets should also be made
available to all personnel involved in these analyses
Additional information on laboratory safety can be
found in references 4-6
4 2 The following compounds covered by this method
have been tentatively classified as known or
suspected human or mammalian carcinogens
benzene, carbon tetrachloride, chloroform, and vinyl
chloride Primary standards of these toxic com-
pounds should be prepared in a hood, and a
NIOSH/MESA approved toxic gas respirator should
be worn when high concentrations are handled
5 APPARATUS AND MATERIALS
5 1 Sample bottles for discrete sampling
5 1 1 Bottle—25 to 40 ml. with screw cap (Pierce 13075,
or equivalent) Detergent wash, rinse with tap and
distilled water, and dry at >105°C for one hour
minumum before use
512 Septum—Teflon-faced silicone (Pierce 12722, or
equivalent), cleaned as above and baked at
100-200 °C for one hour minumum
52
521
522
5 22 1
Purge and trap device—consists of purging device,
trap, and desorber Complete devices are commer-
cially available
Purging device—designed to accept 5 mL samples
with water column at least 3 cm deep The volume of
the gaseous head space between the water and trap
shall be less than 15 mL The purge gas shall be in-
troduced less than 5 mm from the base of the water
column and shall pass through the water as bubbles
with a diameter less than 3 mm The purging device
shown in figure 1 meets these criteria
OPTION At
FOAM TRAP
EXTT 1/4 IN OD
«— U MM OO
INLET IN OD
OOT tM IN OD
10 MM GLASS FRIT
medium porosity
SAMPLE INLET
2 WAY SYRINGE VALVE
17 CM 20 GAUGE SYRINGE NEEDLE
8 MM 00 RUBBER SEPTUM
INLET 11' (NOD
U16 IN OD
/ STAINLESS steel
13X
MOLECULAR SIEVE
PURGE OAS FILTER
RJRGE GAS
1 FLOW CONTROL
FIGURE 1 Purging Device.
Trap—25 to 30 cm x 2 5 mm i d minimum, contain-
ing the following
Methyl silicone packing—one±0 2 cm, 3 percent
OV-1 on 60/80 mesh Chromosorb W, or equivalent
3
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5222
5223
Porous polymer— 15± 1 0 cm, Tenax GC
(2,6-diphenylene oxide polymer), 60/80 mesh,
chromatographic grade, or equivalent
Silica gel—8±10 cm, Davison Chemical, 35/60
mesh, grade 15, or equivalent The trap shown in
figure 2 meets these specifications
PACKING DETAIL
CONSTRUCTION DETAIL
5 MM GLASS WOOL
7 7 CM SILICA GEL
COMPRESSION
FITTING NUT
ANO FERRULES
14 FT 7fl/FOOT
RESISTANCE WIRE
WRAPPED SOLID
1SCMTENAXGC
1 CM 3% OV 1
j- 5 MM GLASS WOOL
THERMOCOUPLE/
CONTROLLER
SENSOR
ELECTRONIC
TEMPERATURE
CONTROL AND
PYROMETER
TUBING 25 CM
0105 IN ID
0125 IN OD
STAINLESS STEEL
523
524
FIGURE 2 Trap Packings and Construction to
Include Desorb Capability.
Desorber—shall heat the trap to 175±5°C, in 45
seconds or less The polymer section of the trap shall
not exceed 180°C, and the remaining sections shall
not exceed 220°C The desorber shown in figure 2
meets these specifications
The purge and trap device may be a separate unit or
coupled to a GC as shown in figures 3 and 4
CARRIER GAS
FLOW CONTROL
LIQUID INJECTION PORTS
COLUMN OVEN
OPTIONAL 4-PORT COLUMN
SELECTION VALVE
REGULATOR
9-PORT
VALVE
CONFIRMATORY COLUMN
TO DETECTOR
ANALYTICAL COLUMN
13X MOLECULAR
SIEVE FILTER
V 1.1 PURGING
11 OEVtCE
NOTE.
ALL UNES BETWEEN TRAP
AND GC SHOULD 8E HEATED
TO eo*c
FIGURE 3 Schematic of Purge and Trap
Device-Purge Mode
5 3 1
5 4
CARRIER GAS
FLOW CONTROL
LIQUID INJECTION PORTS
COLUMN OVEN
OPTIONAL « PORT COLUMN
SELECTION VALVE
REGULATOR
TRAP INLET
S-PORT
VALVE
CONFIRMATORY COLUMN
TO DETECTOR
ANALYTICAL COLUMN
PURGE GAS
FLOW CONTROL
13X MOLECULAR
SIEVE FILTER
|i PURGING
1 1 OEVtCE
NOTE.
ALL LINES BETWEEN TRAP
ANO GC SHOULD BE HEATED
TO arc
53
FIGURE 4 Schematic of Purge and Trap
Device-Desorb Mode.
Gas chromatograph—shall be linearly temperature
programmable with initial and final holds, shall con-
tain a glass jet separator as the MS interface, and
shall produce results which meet the calibration (sec-
tion 7), quality assurance (section 8), and perfor-
mance tests (section 11) of this method
Column—2 8 ± 0 4 m x 2 ± 0 5 mmid glass, packed
with one percent SP-1000 on Carbopak B, 60/80
mesh, or equivalent
Mass spectrometer—70 eV electron impact ioniza-
tion, shall repetitively scan from 20 to 250 amu every
2-3 seconds, and produce a unit resolution (valleys
between m/z 174-176 less than 10 percent of the
height of the m/z 175 peak), background corrected
mass spectrum from 50 ng 4-bromofluorobenzene
(BFB) injected into the GC The BFB spectrum shall
meet the mass-intensity criteria in table 3 All por-
tions of the GC column, transfer lines, and separator
which connect the GC column to the ion source shall
remain at or above the column temperature during
analysis to preclude condensation of less volatile
compounds
TABLE 3
BFB Mass-intensity Specifications
MASS INTENSITY REQUIRED
50
15 to 40 percent of mass 95
75
30 to 60 percent of mass 95
95
base peak, 100 percent
96
5 to 9 percent of mass 95
173
< 2 percent of mass 174
174
> 50 percent of mass 95
176
95 to 100 percent of mass 174
177
5 to 9 percent of mass 1 76
55
551
Data system—shall collect and record MS data, store
mass intensity data in spectral libraries, process
GC/MS data and generate reports, and shall
calculate and record response factors
Data acquisition—mass spectra shall be collected
continuously throughout the analysis and stored on a
mass storage device
4
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5 5 2 Mass spectral libraries—user created libraries con-
taining mass spectra obtained from analysis of
authentic standards shall be employed to reverse
search GC/MS runs for the compounds of interest
(section 7 2)
5 5 3 Data processing—the data system shall be used to
search, locate, identify, and quantify the compounds
of interest in each GC/MS analysis Software routines
shall be employed to compute retention times and
EICP areas Displays of spectra, mass
chromatograms, and library comparisons are re-
quired to verify results
5 5 4 Response factors and multipoint calibrations—the
data system shall be used to record and maintain
lists of response factors (response ratios for isotope
dilution) and generate multi-point calibration curves
(section 7) Computations of relative standard devia-
tion (coefficient of variation) are useful for testing
calibration linearity Statistics on initial and on-going
performance shall be maintained (sections 8 and 11)
5 6 Syringes—5 mL glass hypodermic, with Luer-lok tips
5 7 Micro syringes—10, 25, and 100mL
5 8 Syringe valves—2-way, with Luer ends (Teflon or
Kel-F)
5 9 Syringe—5 mL, gas-tight, with shut-off valve
5 10 Bottles—15 mL, screw-cap with Teflon liner
5 11 Balance—analytical, capable of weighing 0 1 mg
6 REAGENTS AND STANDARDS
6 1 Reagent water—water in which the compounds of in-
terest and interfering compounds are not detected by
this method (section 8 5 2) It may be generated by
any of the following methods
6 1 1 Activated carbon—pass tap water through a carbon
bed (Calgon Filtrasorb-300, or equivalent)
6 1 2 Water purifier—pass tap water through a purifier
(Millipore Super Q, or equivalent)
61 3 Boil and purge—heat tap water to 90-100 °C and
bubble contaminant free inert gas through it for
approx one hour While still hot, transfer the water to
screw-cap bottles and seal with a Teflon-lined cap
6 2 Sodium thiosulfate—ACS granular
6 3 Methanol—pesticide quality or equivalent
6 4 Standard solutions—purchased as solutions or mix-
tures with certification to their purity, concentration,
and authenticity, or prepared from materials of
known purity and composition If compound purity is
96 percent or greater, the weight may be used
without correction to calculate the concentration of
the standard
6 5 Preparation of stock solutions—prepare in methanol
using liquid or gaseous standards per the steps
below Observe the safety precautions given in
section 4
6 5 1 Place approx 9 8 mL of methanol in a 10 mL ground
glass stoppered volumetric flask Allow the flask to
stand unstoppered for approximately 10 minutes or
until all methanol wetted surfaces have dried In each
case, weigh the flask, immediately add the com-
pound, then immediately reweigh to prevent evapor-
ation losses from affecting the measurement
6 5 11 Liquids—using a 100 fil syringe, permit 2 drops of
liquid to fall into the methanol without contacting the
neck of the flask Alternatively, inject a known
volume of the compound into the methanol in the
flask using a micro-syringe
6 5 12 Gases (chloromethane, bromomethane, chloro-
ethane, vinyl chloride)—fill a valved 5 mL gas-tight
syringe with the compound Lower the needle to ap-
prox 5 mm above the methanol meniscus Slowly in-
troduce the compound above the surface of the
meniscus The gas will dissolve rapidly in the
methanol
6 5 2 Fill the flask to volume, stopper, then mix by inverting
several times Calculate the concentration in mg/mL
(ptglfiL) from the weight gain (or density if a known
volume was injected)
6 5 3 Transfer the slock solution to a Teflon sealed screw-
cap bottle Store, with minimal headspace, in the
dark at -10 to -20°C
6 5 4 Prepare fresh standards weekly for the gases and
2-chloroethylvinyl ether All other standards are
replaced after one month, or sooner if comparison
with check standards indicate a change in concentra-
tion Quality control check standards that can be
used to determine the accuracy of calibration stan-
dards are available from the US Environmental Pro-
tection Agency, Environmental Monitoring and Sup-
port Laboratory, Cincinnati, Ohio
6 6 Labeled compound spiking solution—from stock
standard solutions prepared as above, or from mix-
tures, prepare the spiking solution to contain a con-
centration such that a 5-10 mL spike into each 5 mL
sample, blank, or aqueous standard analyzed will
result in a concentration of 20 uglL of each labeled
compound For the gases and for the water soluble
compounds (acrolein, acrylonitrile, acetone, diethyl
ether, and MEK), a concentration of 100/^g/L may be
used Include the internal standards (section 7 5) in
this solution so that a concentration of 20 jug/L in
each sample, blank, or aqueous standard will be
produced
6 7 Secondary standards—using stock solutions,
prepare a secondary standard in methanol to contain
each pollutant at a concentration of 500 ixglml For
the gases and water soluble compounds (section
6 6), a concentration of 2 5 mg/mL may be used
6 7 1 Aqueous calibration standards—using a 25 txL
syringe,add 20MLof the secondary standard (section
6 7) to 50, 100, 200, 500, and 1000 mLof reagent
water to produce concentrations of 200,100, 50, 20,
and 10 /mg/L, respectively If the higher concentration
standard for the gases and water soluble compounds
was chosen (section 6 6), these compounds will be
at concentrations of 1000, 500, 250,100, and 50jug/L
in the aqueous calibration standards
6 7 2 Aqueous performance standard—an aqueous stan-
dard containing all pollutants, internal standards,
labeled compounds, and BFB is prepared daily, and
analyzed each shift to demonstrate performance
(section 11) This standard shall contain either 20 or
5
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100 /ig/L of the labeled and pollutant gases and
water soluble compounds, lO^g/L BFB, and 20M9/L
of all other pollutants, labeled compounds, and inter-
nal standards It may be the nominal 20 mq/L
aqueous calibration standard (section 6 7 1)
6 7 3 A methanolic standard containing all pollutants and
internal standards is prepared to demonstrate
recovery of these compounds when syringe injection
and purge and trap analyses are compared This
standard shall contain either 100 pg/mL or 500
jug/mL of the gases and water soluble compounds,
and 100 /jg/mL of the remaining pollutants and inter-
nal standards (consistent with the amounts in the
aqueous performance standard in 6 7 2)
6 7 4 Other standards which may be needed are those for
test of BFB performance (section 7 1) and for collec-
tion of mass spectra for storage in spectral libraries
(section 7 2)
7 CALIBRATION
7 1 Assemble the gas chromatographic apparatus and
establish operating conditions given in table 2 By
injecting standards into the GC, demonstrate that the
analytical system meets the detection limits in table 2
and the mass-intensity criteria in table 3 for 50 ng
BFB
7 2 Mass spectral libraries—detection and identification
of the compounds of interest are dependent upon the
spectra stored in user created libraries
7 2 1 Obtain a mass spectrum of each pollutant and la-
beled compound and each internal standard by
analyzing an authentic standard either singly or as
part of a mixture in which there is no interference bet-
ween closely eluted components That only a single
compound is present is determined by examination
of the spectrum Fragments not attributable to the
compound under study indicate the presence of an
interfering compound Adjust the analytical condi-
tions and scan rate (for this test only) to produce an
undistorted spectrum at the GC peak maximum An
undistorted spectrum will usually be obtained if five
complete spectra are collected across the upper half
of the GC peak Software algorithms designed to
"enhance" the spectrum may eliminate distortion,
but may also eliminate authentic m/z's or introduce
other distortion
7 2 2 The authentic reference spectrum is obtained under
BFB tuning conditions (section 7 1 and table 3) to
normalize it to spectra from other instruments
7 2 3 The spectrum is edited by saving the 5 most intense
mass spectral peaks and all other mass spectral
peaks greater than 10 percent of the base peak This
spectrum is stored for reverse search and for com-
pound confirmation
7 3 Assemble the purge and trap device Pack the trap
as shown in figure 2 and condition overnight at
170-180 °C by backflushing with an inert gas at a
flow rate of 20-30 mL/min Condition traps daily for a
minimum of 10 minutes prior to use
7 3 1 Analyze the aqueous performance standard (section
6 7 2) according to the purge and trap procedure in
section 10 Compute the area at the primary m/z
(table 4) for each compound Compare these areas
to those obtained by injecting one of the
methanolic standard (section 6 7 3) to determine
compound recovery The recovery shall be greater
than 20 percent for the water soluble compounds,
and 60-110 percent for all other compounds This
recovery is demonstrated initially for each purge and
trap GC/MS system The test is repeated only if the
purge and trap or GC/MS systems are modified in
any way that might result in a change in recovery
TABLE 4
Volatile Organic Compound Characteristic Masses
LABELED COMPOUND
ANALOG
PRIMARY M/Z'S
acetone
do
58/64
acrolein
dj
56/60
acrylonitrile
d3
53/56
benzene
de
78/84
bromodichloromethane
,3C
83/86
bromoform
,3C
173/176
bromomethane
da
96/99
carbon tetrachloride
,3C
47/48
chlorobenzene
d5
112/117
chloroethane
d5
64/71
2-chloroethylvinyl ether
d,
106/113
chloroform
,3C
85/86
chloromethane
d3
50/53
dibromochloromethane
,3C
129/130
1,1-dichloroethane
d3
63/66
1,2-dichloroethane
d.
62/67
1,1-dichloroethene
d2
61/65
trans-1,2-dichloroethene
d2
61/65
1,2-dichloropropane
da
63/67
trans-1,3-dichloropropene
a.
75/79
diethyl ether
dio
74/84
p-dioxane
de
88/96
ethylbenzene
dio
106/116
methylene chloride
d2
84/88
methyl ethyl ketone
da
72/75
1,1,2,2-tetrachloroethane
d2
83/84
tetrachloroethene
,3C2
164/172
toluene
da
92/98
1,1,1-trichloroethane
d3
97/102
1,1,2-trichloroethane
,3C2
83/84
tnchloroethene
,3C
95/1 36
vinyl chloride
d3
62/65
7 3 2 Demonstrate that 100 ng toluene (or toluene-da) pro-
duces an area at m/z 91 (or 98) approx one-tenth that
required to exceed the linear range of the system
The exact value must be determined by experience
for each instrument It is used to match the calibration
range of the instrument to the analytical range and
detection limits required
7 4 Calibration by isotope dilution—the isotope dilution
approach is used for the purgeable organic com-
pounds when appropriate labeled compounds are
available and when interferences do not preclude the
analysis If labeled compounds are not available, or
interferences are present, the internal standard
method (section 7 5) is used A calibration curve en-
compassing the concentration range of interest is
prepared for each compound determined The
relative response (RR) vs concentration (/^tg/L) is
plotted or computed using a linear regression An ex-
6
-------
ample of a calibration curve for toluene using
toluene-da is given in figure 5 Also shown are the
±10 percent error limits (dotted lines) Relative
response is determined according to the pro-
cedures described below A minumum of five data
points are required for calibration (section 7 4 4)
1 1 r
2 10 20 50 100 200
CONCENTRATION (ufl/L)
FIGURE 5 Relative Response Calibration Curve
for Toluene. The Dotted Lines Enclose a ±10
Percent Error Window.
7 4 1 The relative response (RR) of pollutant to labeled
compound is determined from isotope ratio values
calculated from acquired data Three isotope ratios
are used in this process
Rx = the isotope ratio measured in the pure pollutant
(figure 6A)
R = the isotope ratio of pure labeled compound
(figure 6B)
Rm= the isotope ratio measured in the analytical
mixture of the pollutant and labeled com-
pounds (figure 6C)
The correct way to calculate RR is
pp _ (Ry ~ Rm)(Rx 1)
(Rm-Rx)(Ry+1)
If Rm is not between 2Ry and 0 5RX, the method does
not apply and the sample is analyzed by the internal
standard method (section 7 5)
7 4 2 In most cases, the retention times of the pollutant and
labeled compound are the same and isotope ratios
(R's) can be calculated from the EICP areas, where
P _ (area at m,/z)
(area at m2/z)
If either of the areas is zero, it is assigned a value of
one in the calculations, that is, if
area of m,/z = 50721, and
area of m2/z = 0, then
R = 50721 = 50720
1
The m/z's are always selected such that Rx>Ry
When there is a difference in retention times (RT) be-
tween the pollutant and labeled compounds, special
precautions are required to determine the isotope
ratios
Ry, R„, and Rm are defined as follows
R, =
[area m,/z (at RT,)]
Ry =
—
[area m2/z (at RT2)]
_[area m,/z (at RT,)]
743
[area m2/z (at RT2)]
An example of the above calculations can be taken
from the data plotted in figure 6 for toluene and
toluene-ds For these data,
Rx =
_ 168920
1
Ry = —-
60960
n _ 96868
nm —
82508
= 168900
= 0 00001640
= 1 174
The RR for the above data is then calculated using
the equation given in section 7 4 1 For the example,
rr = 1 174 NOTE Not all labeled compounds elute
before their pollutant analogs
(A)
AREA=168920
¦ M/Z 98
• M/Z 92
(B)
AREA=60960
21
¦ M/Z 98
¦ M/Z 92
(C)
M/Z 92 . 96668
M/Z 98 " B2508
• M/Z 98
¦ M/Z 92
7 4 4
FIGURE 6 Extracted Ion Current Profiles for (A)
Toluene, (B) Toluene-dg, and (C) a Mixture of
Toluene and Toluene-dg.
To calibrate the analytical system by isotope dilution,
analyze a 5 mL aliquot of each of the aqueous
calibration standards (section 6 7 1) spiked with an
appropriate constant amount of the labeled com-
pound spiking solution (section 6 6), using the purge
and trap procedure in section 10 Compute the RR at
each concentration
7
-------
7 4 5 Linearity—if the ratio of relative response to concen-
tration for any compound is constant (less than 20
percent coefficient of variation) over the 5 point
calibration range, an averaged relative
response/concentration ratio may be used for that
compound, otherwise, the complete calibration
curve for that compound shall be used over the 5
point calibration range
7 5 Calibration by internal standard—used when criteria
for isotope dilution (section 7 4) cannot be met The
method is applied to pollutants having no labeled
analog and to the labeled compounds The internal
standards used for volatiles analyses are
bromochloromethane, 2-bromo-1 -chloropropane,
and 1,4-dichlorobutane Concentrations of the la-
beled compounds and pollutants without labeled
analogs are computed relative to the nearest eluted
internal standard, as shown in table 2
7 5 1 Response factors—calibration requires the deter-
mination of response factors (RF) which are defined
by the following equation
RF = (As x C|s), where
(A|S X Cg),
As is the EICP area at the characteristic m/z for the
compound in the daily standard
AIS is the EICP area at the characteristic m/z for the
internal standard
CIS is the concentration (/ig/L) of the internal stan-
dard
Cs is the concentration of the pollutant in the daily
standard
7 5 2 The response factor is determined at 10,20, 50,100,
and 200 ugll for the pollutants (optionally at five
times these concentrations for gases and water solu-
ble pollutants—see section 6 6), in a way analogous
to that for calibration by isotope dilution (section
7 4 4) The RF is plotted against concentration for
each compound in the standard (C^ to produce a
calibration curve
7 5 3 Linearity—if the response factor (RF) for any com-
pound is constant (less than 35 percent coefficient of
variation) over the 5 point calibration range, an
averaged response factor may be used for that com-
pound, otherwise, the complete calibration curve for
that compound shall be used over the 5 point range
7 6 Combined calibration—by adding the isotopically
labeled compounds and internal standards (section
6 6) to the aqueous calibration standards (section
6 7 1), a single set of analyses can be used to pro-
duce calibration curves for the isotope dilution and
internal standard methods These curves are verified
each shift (section 11 5) by purging the aqueous per-
formance standard (section 6 7 2) Recalibration is
required only if calibration and on-going performance
(section 11 5) criteria cannot be met
8 QUALITY ASSURANCE/QUALITY CONTROL
8 1 Each laboratory that uses this method is required to
operate a formal quality assurance program The
minimum requirements of this program consist of an
initial demonstration of laboratory capability, analysis
of samples spiked with labeled compounds to
evaluate and document data quality, and analysis of
standards and blanks as tests of continued perfor-
mance Laboratory performance is compared to
established performance criteria to determine if the
results of analyses meet the performance character-
istics of the method
8 1 1 The analyst shall make an initial demonstration of the
ability to generate acceptable accuracy and preci-
sion with this method This ability is established as
described in section 8 2
8 1 2 The analyst is permitted to modify this method to im-
prove separations or lower the costs of
measurements, provided all performance specifica-
tions are met Each time a modification is made to the
method, the analyst is required to repeat the pro-
cedure in section 8 2 to demonstrate method perfor-
mance
8 1 3 Analyses of blanks are required to demonstrate
freedom from contamination and that the compounds
of interest and interfering compounds have not been
carried over from a previous analysis (section 3) The
procedures and criteria for analysis of a blank are
described in sections 8 5
8 1 4 The laboratory shall spike all samples with labeled
compounds to monitor method performance This
test is described in section 8 3 When results of these
spikes indicate atypical method performance for
samples, the samples are diluted to bring method
performance within acceptable limits (section 14 2)
81 5 The laboratory shall, on an on-going basis,
demonstrate through the analysis of the aqueous per-
formance standard (section 6 7 2) that the analysis
system is in control This procedure is described in
sections 11 1 and 11 5
8 1 6 The laboratory shall maintain records to define the
quality of data that is generated Development of ac-
curacy statements is described in sections 8 4 and
115 2
8 2 Initial precision and accuracy—to establish the ability
to generate acceptable precision and accuracy, the
analyst shall perform the following operations
8 2 1 Analyze two sets of four 5-mL aliquots (8 aliquots
total) of the aqueous performance standard (section
6 7 2) according to the method beginning in section
10
8 2 2 Using results of the first set of four analyses in sec-
tion 8 2 1, compute the average recovery (X) in/xg/L
and the standard deviation of the recovery (s) in ug/L
for each compound, by isotope dilution for pollutants
with a labeled analog, and by internal standard for
labeled compounds and pollutants with no labeled
analog
8 2 3 For each compound, compare s and X with the cor-
responding limits for initial precision and accuracy
found in table 5 If s and X for all compounds meet
the acceptance criteria, system performance is ac-
ceptable and analysis of blanks and samples may
begin if, however, any individual s exceeds the
precision limit or any individual X falls outside the
range for accuracy, system performance is unaccep-
table for that compound NOTE The large number of
8
-------
compounds in table 5 present a substantial probabili-
ty that one or more will fail one ot the acceptance
criteria when all compounds are analyzed To deter-
mine if the analytical system is out of control, or if the
failure can be attributed to probability, proceed as
follows
8 2 4 Using the results_of the second set of four analyses,
compute s and X for only those compounds which
failed the test of the first set of four analyses (section
8 2 3) If these compounds now pass, system perfor-
mance is acceptable for all compounds and analysis
of blanks and samples may begin If, however, any of
the same compounds fail again, the analysis system
is not performing properly for the compound (s) in
question In this event, correct the problem and
repeat the entire test (section 8 2 1)
8 3 The laboratory shall spike all samples with labeled
compounds to assess method performance on the
sample matrix
8 3 1 Spike and analyze each sample according to the
method beginning in section 10
8 3 2 Compute the percent recovery (P) of the labeled
compounds using the internal standard method (sec-
tion 7 5)
8 3 3 Compare the percent recovery for each compound
with the corresponding labeled compound recovery
limit in table 5 If the recovery of any compound falls
outside its warning limit, method performance is
unacceptable for that compound in that sample
Therefore, the sample matrix is complex and the
sample is to be diluted and reanalyzed, per section
142
8 4 As part of the QA program for the laboratory, method
accuracy for waste-water samples shall be assessed
and records shall be maintained After the analysis of
five wastewater samples for which the labeled com-
pounds pass the test in section 8 3 3, compute the
average percent recovery (P) and the standard devia-
tion of the percent recovery (sp) for the labeled com-
pounds only Express the accuracy assessment as a
percent recovery interval from P - 2sp to P + 2sp
For example, if P = 90% and sp = 10%, the ac-
curacy interval is expressed as 70-110% Update the
accuracy assessment for each compound on a
regular basis (eg after each 5-10 new accuracy
measurements)
TABLE 5
Acceptance Criteria for Performance Tests
ACCEPTANCE CRITERIA AT 2Q pg/L
INITIAL PRECISION
AND ACCURACY
SECTION 8 2 3
COMPOUND
i (H9A)
% (M9/U
LABELED
COMPOUND
RECOVERY
SECTION 6 3
AND 14 2
P<%>
ON-GOING
ACCURACY
SECTION 11 5
R (HQ/L)
acetone
acrolein
acrylomtrile
note 1 ¦
note 2 ¦
note 2 ¦
benzene
90
13 0 - 28 2
ns-196
4-33
bromodichloromethane
82
6 5-31 5
ns- 199
4 - 34
bromoform
70
7 4- 35 1
ns - 214
6-36
bromomethane
25 0
d - 54 3
ns - 414
d - 61
carbon tetrachloride
69
15 9 - 24 8
42-165
12-30
chlorobenzene
82
14 2 - 29 6
ns - 205
4-35
chloroethane
14 8
2 1 - 46 7
ns - 308
d - 51
2-chloroethylvmyl ether
36 0
d - 69 8
ns - 554
d - 79
chloroform
79
11 6 - 26 3
18-172
8-30
chloromethane
26 0
d - 55 5
ns - 410
d - 64
dibromochloromethane
79
11 2 - 29 1
16 -185
8-32
1,1-dichloroethane
67
11 4-31 4
23-191
9-33
1,2-dichloroethane
7 7
11 6 - 30 1
12 - 192
8-33
1,1-dichloroethene
11 7
d - 49 8
ns-315
d - 52
trans-1,2-dichloroethene
7 4
105-31 5
15-195
8-34
1,2-
-------
8 5 Blanks—reagent water blanks are analyzed to
demonstrate freedom from carry-over (section 3) and
contamination
8 5 1 The level at which the purge and trap system will
carry greater than 5 /ug/L of a pollutant of interest
(table 1) into a succeeding blank shall be determined
by analyzing successively larger concentrations of
these compounds When a sample contains this con-
centration or more, a blank shall be analyzed im-
mediately following this sample to demonstrate no
carry-over at the 5 /ug/L level
8 5 2 With each sample lot (samples analyzed on the same
8 hr shift), a blank shall be analyzed immediately after
analysis of the aqueous performance standard (sec-
tion 11 1) to demonstrate freedom from contamina-
tion If any of the compounds of interest (table 1) or
any potentially interfering compound is found in a
blank at greater than 10 jug/L (assuming a response
factor of 1 relative to the nearest eluted internal stan-
dard for compounds not listed in table 1), analysis of
samples is halted until the source of contamination is
eliminated and a blank shows no evidence of con-
tamination at this level
8 6 The specifications contained in this method can be
met if the apparatus used is calibrated properly, then
maintained in a calibrated state The standards used
for calibration (section 7), calibration verification
(section 11 5) and for initial (section 8 2) and on-
going (section 11 5) precision and accuracy should
be identical, so that the most precise results will be
obtained The GC/MS instrument in particular will
provide the most reproducible results if dedicated to
the settings and conditions required for the analyses
of volatiles by this method
8 7 Depending on specific program requirements, field
replicates may be collected to determine the preci-
sion of the sampling technique, and spiked samples
may be required to determine the accuracy of the
analysis when internal or external standard methods
are used
9 SAMPLE COLLECTION, PRESERVATION, AND
HANDLING
91 Grab samples are collected in glass containers hav-
ing a total volume greater than 20 mL Fill sample
bottles so that no air bubbles pass through the sam-
ple as the bottle is filled Seal each bottle so that no
air bubbles are entrapped Maintain the hermetic seal
on the sample bottle until time of analysis
9 2 Samples are maintained at 0-4 °C from the time of
collection until analysis If the sample contains
residual chlorine, add sodium thiosulfate preser-
vative (10 mg/40 mL) to the empty sample bottles
just prior to shipment to the sample site EPA
Methods 330 4 and 330 5 may be used for measure-
ment of residual chlorine (reference 8) If preser-
vative has been added, shake the bottle vigorously
for one minute immediately after filling
9 3 Experimental evidence indicates that some aromatic
compounds, notably benzene, toluene, and ethyl
benzene are susceptible to rapid biological degrada-
tion under certain environmental conditions
94
Refrigeration alone may not be adequate to preserve
these compounds in wastewaters for more than
seven days For this reason, a separate sample
should be collected, acidified, and analyzed when
these aromatics are to be determined Collect about
500 mL of sample in a clean container Adjust the pH
of the sample to about 2 by adding HC1 (1 +1) while
stirring Check pH with narrow range (1 4 to 2 8) pH
paper Fill a sample container as described in section
91 If residual chlorine is present, add sodium
thiosulfate to a separate sample container and fill as
in section 9 1
All samples shall be analyzed within 14 days of col-
lection
10 PURGE, TRAP, AND GC/MS ANALYSIS
10 1 Remove standards and samples from cold storage
and bring to 20-25 °C
10 2 Adjust the purge gas flow rate to 40 ± 4 mL/min
Attach the trap inlet to the purging device and set the
valve to the purge mode (figure 3) Open the syringe
valve located on the purging device sample introduc-
tion needle (figure 1)
10 3 Remove the plunger from a 5-mL syringe and attach
a closed syringe valve Open the sample bottle and
carefully pour the sample into the syringe barrel until
it overflows Replace the plunger and compress the
sample Open the syringe valve and vent any
residual air while adjusting the sample volume to 5 0
mL Because this process of taking an aliquot
destroys the validity of the sample for future analysis,
fill a second syringe at this time to protect against
possible loss of data Add an appropriate amount of
the labeled compound spiking solution (section 6 6)
through the valve bore, then close the valve
10 4 Attach the syringe valve assembly to the syringe
valve on the purging device Open both syringe
valves and inject the sample into the purging
chamber
10 5 Close both valves and purge the sample for 11 0 ±
0 1 minutes at 20-25°C
10 6 After the 11 minute purge time, attach the trap to the
chromatograph and set the purge and trap apparatus
to the desorb mode (figure 4) Desorb the trapped
compounds into the GC column by heating the trap
to 170-180 °C while backflushing with carrier gas at
20-60 mL/min for four minutes Start MS data acquisi-
tion upon start of the desorb cycle, and start the GC
column temperature program 3 minutes later Table
2 summarizes the recommended operating condi-
tions for the gas chromatograph Included in this
table are retention times and detection limits that
were achieved under these conditions An example
of the separations achieved by the column listed is
shown in figure 8 Other columns may be used pro-
vided the requirements in section 8 can be met If the
priority pollutant gases produce GC peaks so broad
that the precision and recovery specifications (sec-
tion 8 2) cannot be met, the column may be cooled to
ambient or sub-ambient temperature to sharpen
these peaks
lO
-------
10 7 While analysis of the desorbed compounds pro- 11512
ceeds, empty the purging chamber using the sample
introduction syringe Wash the chamber with two
5-mL portions of reagent water After the purging
device has been emptied, allow the purge gas to vent
through the chamber until the frit is dry, so that it is
ready for the next sample
10 8 After desorbing the sample for four minutes, recondi-
tion the trap by returning to the purge mode Wait 15
seconds, then close the syringe valve on the purging
device to begin gas flow through the trap Maintain 115 2
the trap temperature at 170-180 °C After approx-
imately seven minutes, turn off the trap heater and
open the syringe valve to stop the gas flow through
the trap When cool, the trap is ready for the next
sample
11 SYSTEM PERFORMANCE
111 At the beginning of each 8 hr shift during which
analyses are performed, system calibration and per-
formance shall be verified for all pollutants and la-
beled compounds For these tests, analysis of the
aqueous performance standard (section 6 7 2) shall
be used to verify all performance criteria Adjustment
and/or recalibration (per section 7) shall be per-
formed until all performance criteria are met Only
after all performance criteria are met may blanks and
samples be analyzed
11 2 BFB spectrum validity—the criterai in table 3 shall be
met
11 3 Retention times—the absolute retention times of all
compounds shall approximate those given in table 2
114 GC resolution—the valley height between toluene
and toluene-d« (at m/z 91 and 98 plotted on the same
graph) shall be less than 10 percent of the taller of the
two peaks
11 5 Calibration verification and on-going precision and
accuracy—compute the concentration of each pollu-
tant (table 1) by isotope dilution (section 7 4) for
those compounds which have labeled analogs Com-
pute the concentration of each pollutant (table 1)
which has no labeled analog by the internal standard
method (section 7 5) Compute the concentration of
the labeled compounds by the internal standard
method These concentrations are computed based
on the calibration data determined in section 7
115 1 For each pollutant and labeled compound, compare
the concentration with the corresponding limit for on-
going accuracy in table 5 If all compounds meet the
acceptance criteria, system performance is accep-
table and analysis of blanks and samples may con-
tinue If any individual value falls outside the range
given, system performance is unacceptable for that 12 11
compound NOTE The large number of compounds
in table 5 present a substantial probability that one or
more will fail the acceptance criteria when all com-
pounds are analyzed To determilne if the analytical 1212
system is out of control, or if the failure may be at-
tributed to probability, proceed as follows
115 11 Analyze a second aliquot of the aqueous perfor-
mance standard (section 6 7 2)
Compute the concentration for only those com-
pounds which failed the first test (section 1151) If
these compounds now pass, system performance is
acceptable for all compounds and analyses of blanks
and samples may proceed If, however, any of the
compounds fail again, the measurement system is
not performing properly for these compounds In this
event, locate and correct the problem or recalibrate
the system (section 7), and repeat the entire test (sec-
tion 11 1) for all compounds
Add results which pass the specification in 11 5 1 2
to initial (section 8 2) and previous on-going data Up-
date OC charts to form a graphic representation of
laboratory performance (figure 7) Develop a state-
ment of accuracy for each pollutant and labeled com-
pound by calculating the average percent recovery
(R) and the standard deviation of percent recovery
(sr) Express the accuracy as a recovery interval from
R - 2sr to R + 2sr For example, if R = 95% and sr
= 5%, the accuracy is 85-105 percent
3! 120,000
H
<
2 100,000
oc
<
*
}? 80,000
TOLUENE D,
•+3s
3s
8 9 10
£§
in 3
Ui u]
> z
1 10
100
090
ANALYSIS NUMBER
-J I I l_
TOLUENE
1 I I T I 1 I I I
6/1 6/1 6/1 6/1 6f2 6/2 6/3 6/3 6/4 6/5
DATE ANALYZED
+ 39
-3s
12
12 1
FIGURE 7 Quality Control Charts Showing Area
(top graph) and Relative Response of Toluene
to Toluene-d, (lower graph) Plotted as a
Function of Time or Analysis Number.
QUALITATIVE DETERMINATION-accomplished by
comparison of data from analysis of a sample or
blank with data from analysis of the shift standard
(section 111) Identification is confirmed when spec-
tra and retention times agree per the criteria below
Labeled compounds and pollutants having no la-
beled analog
The signals for all characteristic masses stored in the
spectral library (section 7 2 3) shall be present and
shall maximize within the same two consecutive
scans
Either (1) the backgound corrected EICP areas, or (2)
the corrected relative intensities of the mass spectral
peaks at the GC peak maximum shall agree within a
factor of two (0 5 to 2 times) for all masses stored in
the library
11
-------
12 13 The retention time relative to the nearest eluted inter-
nal standard shall be within ± 7 scans or ± 20
seconds, whichever is greater of this difference in the
shift standard (section 111)
12 2 Pollutants having a labeled analog
12 2 1 The signals for all characteristic masses stored in the
spectral library (section 7 2 3) shall be present and
shall maximize within the same two consecutive
scans
12 2 2 Either (1) the backgound corrected EICP areas, or (2)
the corrected relative intensities of the mass spectral
peaks at the GC peak maximum shall agree within a
factor of two for all masses stored in the spectral
library
12 2 3 The retention time difference between the pollutant
and its labeled analog shall agree within ± 2 scans
or ± 6 seconds (whichever is greater) of this dif-
ference in the shift standard (section 11 1)
12 3 Masses present in the experimental mass spectrum
that are not present in the reference mass spectrum
shall be accounted for by contaminant or backgound
ions If the experimental mass spectrum is con-
taminated, an experienced spectrometrist (section
1 4) is to determine the presence or absence of the
compound
13 QUANTITATIVE DETERMINATION
13 1 Istope dilution—by adding a known amount of a
labeled compound to every sample prior to purging,
correction for recovery of the pollutant can be made
because the pollutant and its labeled analog exhibit
the same effects upon purging, desorption, and gas
chromatography Relative response (RR) values for
sample mixtures are used in conjunction with calibra-
tion curves described in section 7 4 to determine
concentrations directly, so long as labeled com-
pound spiking levels are constant For the toluene ex-
ample given in figure 6 (section 7 4 3), RR would be
equal to 1 174 For this RR value, the toluene calibra-
tion curve given in figure 5 indicates a concentration
of 31 8 figIL
13 2 Internal standard—calculate the concentration using
the response factor determined from calibration data
(section 7 5) and the following equation
Concentration = (Asx cis)
(A,s x RF)
where the terms are as defined in section 7 5 1
13 3 If the EICP area at the quantitation mass for any com-
pound exceeds the calibration range of the system,
the sample is diluted by successive factors of 10 and
these dilutions are analyzed until the area is within
the calibration range
13 4 Report results for all pollutants and labeled com-
pounds (table 1) found in all standards, blanks, and
samples, in ^g/L, to three significant figures Results
for samples which have been diluted are reported at
the least dilute level at which the area at the quantita-
tion mass is within the calibration range (section
13 3) and the labeled compound recovery is within
the normal range for the Method (section 14 2)
14 ANALYSIS OF COMPLEX SAMPLES
14 1 Untreated effluents and other samples frequently
contain high levels (>1000 iigll) of the compounds
of interest and of interfering compounds Some
samples will foam excessively when purged, others
will overload the trap and/or GC column
14 2 Dilute 0 5 mL of sample with 4 5 mL of reagent water
and analyze this diluted sample when labeled com-
pound recovery is outside the range given in table 5
If the recovery remains outside of the range for the
diluted sample, the aqueous performance standard
shall be analyzed (section 11) and calibration verified
(section 115) If the recovery for the labeled com-
pound in the aqueous performance standard is out-
side the range given in table 5, the analytical system
is out of control In this case, the instrument shall be
repaired, the performance specifications in section
11 shall be met, and the analysis of the undiluted
sample shall be repeated If the recovery for the
aqueous performance standard is within the range
given in table 5, the method does not work on the
sample being analyzed and the result may not be
reported for regulatory compliance purposes
14 3 Reverse search computer programs can misinterpret
the spectrum of chromatographically unresolved
pollutant and labeled compound pairs with overlapp-
ing spectra when a high level of the pollutant is pre-
sent Examine each chromatogram for peaks greater
then the height of the internal standard peaks These
peaks can obscure the compounds of interest
15 METHOD PERFORMANCE
15 1 The specifications for this method were taken from
the interlaboratory validation of EPA Method 624
(reference 9) Method 1624 has been shown to yield
slightly better performance on treated effluents than
method 624 Additional method performance data
can be found in Reference 10
15 2 A chromatogram of the 20 /xg/L aqueous perfor-
mance standards (sections 6 7 2 and 11 1) is shown
in figure 8
12
-------
MASS CHROHATOGRAH DATA: UOAI01945 «1 SCANS 1 TO 1208
89/81/84 23:95:80 CALI: UOAI01945 II
SAMPLE: UO,S,OPR,08020,68,U,NA:NA,NAJ
CONDS.: 1624B, 3.811,2MM, 3045,45-24808,15S240,20t1L/MINJ
RANGE: C 1,1288 LABEL: N 0, 4.0 QUAN: A 8, 1.8 J 0 BASE: U 20, 3
222976.
46.514
250.575
251
1200 SCAN
800
1088
600
200
6:58 13:48 28:38 27:20 34:10 41:88 TINE
FIGURE 8 Chromatogram of Aqueous Performance Standards
16 REFERENCES
1 "Performance Tests for the Evaluation of Com-
puterized Gas Chromatography/Mass Spectrometry
Equipment and Laboratories," USEPA, EMSUCincin-
nati, OH 45268, EPA-600/4-80-025 (April 1980)
2 Bellar, T A and Lichtenberg, J J, "Journal
American Water Works Association," 66, 739 (1974)
3 Bellar, T A and Lichtenberg, J J , "Semi-automated
Headspace Analysis of Drinking Waters and In-
dustrial Waters for Purgeable Volatile Organic Com-
pounds," in Measurement of Organic Pollutants
Water and Wastewater, C E VanHall, ed , American
Society for Testing Materials, Philadelphia, PA,
Special Technical Publication 686, (1978)
4 "Working with Carcinogens," DHEW, PHS, NIOSH,
Publication 77-206 (1977)
5 "OSHA Safety and Health Standards, General
Industry," 29CFR1910, OSHA 2206, (1976)
6 "Safety in Academic Chemistry Laboratories,"
American Chemical Society Publication, Committee
on Chemical Safety (1979)
7 "Handbook of Analytical Quality Control in Water
and Wastewater Laboratories," USEPA, EMSL/Cin-
cinnati, OH 45268, EPA-4-79-019 (March 1979)
8 "Methods 330 4 and 330 5 for Total Residual
Chlorine," USEPA, EMSL/Cincinnati, OH 45268,
EPA-4-79-020 (March 1979)
9 "Test Method Purgeables—Method 624," USEPA,
EMSL/Cincinnati, OH 45268
10 Colby, B N, Beimer, R G , Rushneck, D R, and
Telliard, W A , "Isotope Dilution Gas
Chromatography-Mass Spectrometry for the Deter-
mination of Priority Pollutants in Industrial Effluents,"
USEPA, Effluent Guidelines Division, Washington,
DC 20460 (1980)
13
-------
Method 1625 Revision B
SEMIVOLATILE ORGANIC COMPOUNDS BY ISOTOPE DILUTION GC/MS
1 SCOPE AND APPLICATION
1 1 This methoc is designed to determine the semivolatile
toxic organic pollutants associated with the 1976
Consent Decree and additional compounds amenable
to extraction and analysis by capillary column gas
chromatography-mass spectrometry (GC/MS)
i 2 The chemical compounds listed in tables 1 and 2 may
be determined in municipal and industrial discharges
by this method The method is designed to meet the
survey requirements of EPA's Industrial Technology
Division (ITD) and the National Pollutants Discharge
Elimination System (NPDES) under 40 CFR 136 1
Any modifications of this method, beyond those ex-
pressly permitted, shall be considered as majcf
modifications subject to application and approval of
alternate test procedures under 40 CFR 136 4 and
136 5
Table 1
Base/Neutral Extractable Compounds
POLLUTANT
LABELED COMPOUND
COMPOUND
STORET
CAS
EGD
NPDES
ANALOG
CAS
EGD
acenaphthene
34205
83-32-9
001 B
001
B
dio
15067-20-2
201 B
acenaphthylene
34200
208-96-8
077 B
002
B
do
93951-97-4
277 B
anthracene
34220
120-1 2-7
078 B
003
B
dio
1719-06-8
278 B
benzidine
39120
92-87-5
005 B
004
B
ds
92890-63-6
205 B
benzo(a)anthracene
34526
56-55-3
072 B
005
B
di2
1718-53-2
272 B
benzo(b)tluoianthene
34230
205-99-2
074 B
007
B
di2
93951-98-5
274 B
benzo(k)fluoianlhene
34242
207-08-9
075 B
009
B
di2
93952-01-3
275 B
benzo(a)pyrene
34247
50-32-B
973 B
006
B
di2
63466-71-7
273 B
benzo(ghi)perylene
34521
191-24-2
079 B
008
B
d,2
93951-66-7
279 B
biphenyl (Appendix C)
81513
92-54-4
512 B
dio
1486-01-7
612 B
bis(2-chloroethyl) ether
34273
111-44-4
018 B
011
B
do
93952-02-4
218 B
bis (2-chloroethoxy) methane
34278
111-91-1
043 B
010
B
do
93966-78-0
243 B
bis(2-chloroisopropyl) ether
34283
108-60-1
042 B
012
B
d,2
93951-67-8
242 B
bis(2-ethylhexyl) phthalate
39100
117-81-7
066 B
013
B
d4
93951-87-2
266 B
4-bromophenyl phenyl ether
34636
101-55-3
041 B
014
B
d5
93951-83-8
241 B
butyl benzyl phthalate
34292
85-68-7
067 B
015
B
d4
93951-88-3
267 B
n-Cio (Appendix C)
77427
124-18-5
517 B
d22
16416-29-8
617 B
n-C12 (Appendix C)
77588
112-40-3
506 B
d2e
16416-30-1
606 B
n-CM (Appendix C)
77691
629-59-4
518 B
n-Ci6 (Appendix C)
77757
544-76-3
519 8
dj4
15716-08-2
619 B
n-C, 8 (Appendix C)
77804
593-45-3
520 B
n-C2o (Appendix C)
77830
112-95-8
521 B
d«2
62369-67-9
621 B
n-C22 (Appendix C)
77859
629-97-9
522 B
n-C24 (Appendix C)
77886
646-31-1
523 B
dso
16416-32-3
623 B
n-C26 (Appendix C)
77901
630-01-3
524 B
n-C28 (Appendix C)
78116
630-02-4
525 B
625 B
n-C3o (Appendix C)
78117
638-68-6
526 B
ds2
93952-07-9
626 B
carbazole (4c)
77571
86-74-8
528 B
da
38537-24-5
628 B
2-chloronaphthalene
34581
81-58-7
020 B
016
B
d,
93951-84-9
220 B
4-chlorophenyl phenyl ether
34641
7005-72-3
040 B
017
B
d5
93951-85-0
240 B
chrysene
34320
218-01-9
076 B
018
B
di2
1719-03-5
276 B
p-cymene (Appendix C)
77356
99-87-6
513 B
du
93952-03-5
613 B
dibenzo(a,h)anthracene
34556
53-70-3
082 B
019
B
du
13250-98-1
282 B
dibenzoluran (Appendix C & 4c)
81302
132-64-9
505 B
da
93952-04-6
605 B
dibenzolhiophene (Synfuel)
77639
132-65-0
504 B
do
33262-29-2
604 B
di-n-butyl ph halate
3911C
84-74-2
068 B
026
B
d,
93952-11-5
268 B
1,2-dichlorobenzene
34536
95-50-1
025 B
020
B
d4
2199-69-1
225 B
1,3-dichlorobenzene
34566
541-73-1
026 B
021
B
d4
2199-70-4
226 B
1,4-dichlorobenzene
34571
106-46-7
027 B
022
B
d4
3855-82-1
227 B
3.3-dichlorobenzidine
34631
91-94-1
028 B
023
B
do
93951-91-8
228 B
diethyl phthalate
34336
84-66-2
070 B
024
B
d4
93952-12-6
270 B
2,4-dimethylphenol
34606
105-67-9
034 B
003
B
ds
93951-75-8
234 B
dimethyl phtnalate
34341
131-11-3
071 B
025
B
d4
93951-89-4
271 B
2,4-dinitrotoluene
34611
121-14-2
035 B
027
B
d,
93951-68-9
235 B
2,6-dimtrotoluene
34626
606-20-2
036 B
028
B
d3
93951-90-7
236 B
di-n-octyl phthalate
34596
117-84-0
069 B
029
B
d4
93952-13-7
269 B
diphenylamine (Appendix C)
77579
1 22-39-4
507 B
dio
37055-51-9
607 B
1
-------
Table 1 (Continued)
Base/Neutral Extractable Compounds
POLLUTANT
LABELED COMPOUND
COMPOUND
STORET
CAS
EGD
NPDES
ANALOG
CAS
EGD
diphenyl ether (Appendix C)
77587
101-84-8
508 B
dio
93952-05-7
608 B
1,2-diphenylhydrazme
34346
122-66-7
037 B
030 B
d,o
93951-92-9
237 B
fluoranthene
34376
206-44-0
039 B
031 B
dio
93951-69-0
231 B
fluorene
34381
86-73-7
080 B
032 B
dio
81103-79-9
080 B
hexachlorobenzene
39700
118-74-1
009 B
033 B
,3C«
93952-14-8
209 B
hexachlorobutadiene
34391
87-68-3
052 B
034 B
,3C4
93951-70-3
252 B
hexachloroethane
34396
67-72-1
012 B
036 B
,3C
93952-15-9
212 B
hexachlorocyclopentadiene
34386
77-47-4
053 B
035 B
,3C.
93951-71-4
253 B
ideno(1,2,3-cd)pyrene
34403
193-39-5
083 B
037 B
isophorone
34408
78-59-1
054 B
038 B
do
93952-16-0
254 B
naphthalene
34696
91-20-3
055 B
039 B
da
1146-65-2
255 B
beta-naphthylamine (Appendix C)
82553
91-59-8
056 B
040 B
d7
93951-94-1
602 B
nitrobenzene
34447
98-95-3
056 B
040 B
d5
4165-60-0
256 B
N-nitrosodimethylamine
34438
62-75-9
061 B
041 B
da
17829-05-9
261 B
N-nitrosodi-n-proplylamine
34428
621-64-7
063 B
042 B
d,.
93951-96-3
263 B
N-nitrosodiphenylamine
34433
86-30-6
062 B
043 B
do
93951-95-2
262 B
phenanthrene
34461
85-01-8
081 B
044 B
dio
1517-22-2
281 B
phenol
34694
108-95-2
065 B
010 B
d5
4165-62-2
265 B
alpha-picolme (Synfuel)
77088
109-06-8
503 B
d,
93951-93-0
503 B
pyrene
34469
129-00-0
084 B
045 B
dio
1718-52-1
284 B
styrene (Appendix C)
77128
100-42-5
510 B
ds
5161-29-5
610 B
alpha-terpmeol (Appendix C)
77493
98-55-5
509 B
d3
93952-06-8
609 B
1,2,3-trichlorobenzene (4c)
77613
87-61-6
529 B
d3
3907-98-0
629 B
1,2.4-trichlorobenzene
34551
120-82-1
008 B
046 B
ds
93952-16-0
208 B
TABLE 2
Acid Extractable Compounds
POLLUTANT
LABELED COMPOUND
COMPOUND
STORET
CAS
EGD
NPDES
ANALOG
CAS
EGD
4-chloro-3-methylphenol
34452
59-50-7
022
A
008
A
d2
93951-72-5
222 A
2-chlorophenol
34586
95-57-8
024
A
001
A
d«
93951-73-6
224 A
2,4-dichlorophenol
34601
120-83-2
031
A
002
A
d3
93951-74-7
231 A
2.4-dinilro phenol
34616
51-28-5
059
A
005
A
d3
93951-77-0
259 A
2-methyl-4,6-dinilrophenol
34657
534-52-1
060
A
004
A
d2
93951-76-9
260 A
2-nitrophenol
34591
88-75-5
057
A
006
A
d<
93951-75-1
257 A
4-mtrophenol
34646
100-02-7
058
A
007
A
di
93951-79-2
258 A
pentachlorophenol
39032
87-86-5
064
A
009
A
,3Ca
85380-74-1
264 A
2,3.6-trichlorophenol (4c)
77688
933-75-5
530
A
d2
93951-81-6
630 A
2,4,5-trichlorophenol (4c)
95-95-4
531
A
dz
93951-82-7
631 A
2,4,6-tnchlorophenol
34621
88-06-2
021
A
011
A
d2
93951-80-5
221 A
1 3 The detection limit of this method is usually depen-
dent on the level of interferences rather than in-
strumental limitations The limits listed in tables 3 and
4 represent the minimum quantity that can be
detected with no interferences present
1 4 The GC/MS portions of this method are for use only
by analysts experienced with GC/MS or under the
close supervision of such qualified persons
Laboratories unfamiliar with the analyses of en-
vironmental samples by GC/MS should run the per-
formance tests in reference 1 before beginning
2 SUMMARY OF METHOD
2 1 Stable isotopically labeled analogs of the com-
pounds of interest are added to a one liter
wastewater sample The sample is extracted at pH
12-13, then at pH <2 with methylene chloride using
continuous extraction techniques The extract is
dried over sodium sulfate and concentrated to a
volume of one mL An internal standard is added to
the extract, and the extract is injected into the gas
chromatograph (GC) The compounds are separated
by the GC and detected by a mass spectrometer
(MS) The labeled compounds serve to correct the
variability of the analytical technique
2 2 Identification of a compound (qualitative analysis) is
performed by comparing the GC retention time and
the background corrected characteristic spectral
masses with those of authentic standards
2 3 Quantitative analysis is performed by GC/MS using
extracted ion current profile (EICP) areas Isotope
dilution is used when labeled compounds are
available, otherwise, an internal or external standard
method is used
2 4 Quality is assured through reproducible calibration
and testing of the extraction and GC/MS systems
2
-------
3 CONTAMINATION AND INTERFERENCES
3 1 Solvents, reagents, glassware, and other sample
processing hardware may yield artifacts and/or
elevated baselines jcausing misinterpretation of
chromatograms and spectra All materials shall be
demonstrated to be free from interferences under the
conditions of the analysis by running method blanks
initially and with each sample lot (samples started
through the extraction process on a given 8 hr shift,
32
to a maximum of 20) Specific selection of reagents
and purification of solvents by distillation in all-glass
systems may be required Glassware and, where
possible, reagents are cleaned by solvent rinse and
baking at 450 °C for one hour minimum
Interferences coextracted from samples will vary
considerably from source to source, depending ori
the diversity of the industrial complex or municipality
being sampled
TABLE 3
Gas Chromatography of Base/Neutral Extractable Compounds
EGD
RETENTION TIME
DETECTION
NO
MEAN
EGD
LIMIT (2)
<1)
COMPOUND
(SEC)
REF
RELATIVE
(MO/L)
164
2,2-'difluorobiphenyl (internal standard)
1163
164
1 000-1 000
10
061
N-nitrosodimethylamme'
385
164
0 264-0 398
50
603
aloha picoline-d?
417
164
0 326-0 393
50
703
alpha picolme
426
603
1 006-1 028
50
610
st/rene-d5
546
164
0 450-0 488
10
710
styrene
549
610
1 002-1 009
10
613
p-cymene-dn
742
164
0 624-0 652
10
7I3
p-cymene
755
613
1 008-1 023
10
265
phenol-ds
696
164
0 584-0 613
10
365
phenol
700
265
0 995-1 010
10
218
bis(2-chloroethyl) ether-d8
696
164
0 584-0 607
10
318
bis(2-chloroethyl) ether
704
218
1 007-1 016
10
6-7
n-decane-d22
698
164
0 585-0 615
10
7" 7
n-decane
720
617
1 022-1 038
10
266
1,3-dichlorobenzene-d4
722
164
0 605-0 636
10
326
1,3-dichlorobenzene
724
226
0 998-1 008
10
227
1,4-dichlorobenzene-d4
737
164
0 601-0 666
10
327
1,4-dichlorobenzene
740
227
0 997-1 009
10
225
1,2-dichlorobenzene-d4
758
164
0 632-0 667
10
325
1,2-dichlorobenzene
760
225
0 995-1 008
10
242
bis(2-chloroisopropyl) ether-d12
788
164
0 664-0 691
10
342
bis(2-chloroisopropyl) ether
799
242
1 010-1 016
10
212
hexachloroethane-,3C
819
164
0 690-0 717
10
312
hexachloroethane
823
212
0 999-1 001
10
063
N-nitrosodi-n-propylamine *
830
164
0 701-0 721
2Cf
256
nitrobenzene-d5
845
164
0 706-0 727
10
356
nitiobenzene
849
256
1 002-1 007
10
254
isophorone-da
881
164
0 747-0 767
10
354
isophorone
889
254
0 999-1 017
10
234
2,4-dimelhylphenol-d3
921
164
0 781-0 803
10
334
2,4-dimelhylphenol
924
234
0 999-1 003
10
043
bis(2-chloroethoxy) methane"
939
164
0 799-0 815
10
208
1,2,4-trichlorobenzene-d3
955
164
0 813-0 830
10
308
1,2,4-tnchlorobenzene
958
208
1 000-1 005
10
255
naphthalene-dn
963
164
0 819-0 836
10
355
naphthalene
967
255
1 001-1 006
10
609
alpia-terpineol-dj
973
164
0 829-0 844
10
709
alpia-terpineol
975
609
0 998-1 008
10
606
n-dodecane-d26
953
164
0 730-0 908
10
706
n-dodecane
981
606
0 986-1 051
10
529
1,2,3-tnchlorobenzene*
1003
164
0 855-0 870
10
252
he>achlorobutadiene-,3C4
1005
164
0 856-0 871
10
352
hexachlorobutadiene
1006
252
0 999-1 002
10
253
hexachlorocyclopentadiene-,3C»
1147
164
0 976-0 986
10
353
hexachlorocyclopentadiene
1142
253
0 999-1 001
10
220
2-chloronaphthalene-d7
1185
164
1 014-1 024
10
320
2-chloronaphthalene
1200
220
0 997-1 007
10
518
n-tetradecane*
1203
164
1 015-1 026
10
612
biphenyl-d10
1205
164
1 016-1 027
10
712
biphenyl
1195
612
1 001-1 006
10
608
diphenyl ether-d,0
1211
164
1 036-1 047
10
708
diphenyl ether
1216
608
0 997-1 009
10
277
acenaphthylene-de
1265
164
1 080-1 095
10
3
-------
EGD
NO
(1)
377
271
371
236
336
201
301
605
705
602
702
280
360
240
340
270
370
619
719
235
335
237
337
607
707
262
362
041
209
309
281
520
381
278
378
604
704
528
621
721
268
368
239
339
284
384
205
305
522
623
723
067
276
376
272
372
228
328
266
366
524
269
369
525
4
10
10
10
10
10
10
10
10
10
50
50
10
10
10
10
10
10
10
10
10
10
20
20
20
20
20
20
10
10
10
10
10
10
10
10
10
10
20
10
10
10
10
10
10
10
10
50
50
10
10
10
10
10
10
10
10
50
50
10
10
10
10
10
10
TABLE 3 (Continued)
Gas Chromatography of Base/Neutral Extractable Compounds
RETENTION TIME
MEAN
EGD
COMPOUND
(SEC)
REF
RELATIVE
acenaphthylene
1247
277
1 000-1 004
dimethyl phthalate-d4
1269
164
1 083-1 102
dimethyl phthalate
1273
271
0 998-1 005
2.6-dinitrotoluene-
-------
TABLE 3 (Continued)
Gas Chromatography of Base/Neutral Extractable Compounds
EGD
RETENTION TIME
DETECTION
NO
MEAN
EGO
LIMIT (2)
(1)
COMPOUND
(SEC)
REF
RELATIVE
(MQ/U
274
benzo(b)fluoranthene-d,2
2281
164
1 902-2 025
10
354
benzo(b)fluoranthene
2293
274
1 000-1 005
10
275
benzo(k)fluoranthene-d, 2
2287
164
1 906-2 033
10
375
benzo{k)fluoranthene
2293
275
1 000-1 005
10
273
benzofajpyrene-d)!
2351
164
1 954-2 088
10
373
benzo(a)pyrene
2350
273
1 000-1 004
10
626
r-triacontane-ds!
2384
164
1 972-2 127
10
.'26
n-triacontane
2429
626
1 011-1 028
10
083
mdeno(i .2 3-cd)pyrene'
2650
164
2 119-2 356
20
082
dibenzo(a,h)anthracene *
2660
164
2 121-2 358
20
279
benzo(ghi)perylene-dij
2741
164
2 187-2 524
20
379
benzo(ghi)perylene
2750
279
1 001-1 006
20
(1) Reference numbers beginning with 0 1 01 5 indicate a pollutant quantified by the internal standard method, reference numbers beginning with 2 or 6
indicate a labeied compound quantified by the internal standard method reference numbers beginning with 3 or 7 indicate a pollutant quantified by
isotope dilution
(2) This is a minimum level at which the entire GC/MS system must give lecogmzable mass spectra (background corrected) and acceptable calibration
po nts
(3) detected as azobenzene
(4) detected as ciphenylamine
' specification derived from related compound
Column 30 ± 2 m x 0 25 ± 0 02 mm i d 94% methyl, 4% phenyl, 1 % vinyl bonded phase fused silica capillary
Temperature program 5 min at 30 °C 30 - 280 °C at 8°C per mm isothermal at 280 °C until benzo(ghi)perylene elutes
Gas velocity 30 ± 5 cm/sec
TABLE 4
Gas Chromatography of Acid Extractable Compounds
EGD
RETENTION TIME
DETECTION
NO
MEAN
EGD
LIMIT (2)
(1)
COMPOUND
(SEC)
REF
RELATIVE
(pg/L)
164
2,2'-difluorobiphenyl (internal standard)
1163
164
1 000-1 000
10
224
2-chlorophenol-d«
701
164
0 587-0 618
10
324
2-chlorophenol
705
224
0 997-1 010
10
257
2-nitrophenol-d.
898
164
0 761-0 783
20
357
2-nitrophenol
900
257
0 994-1 009
20
231
2 4-dichlorophenol-da
944
164
0 802-0 822
10
331
2 4-dichlorophenol
947
231
0 997-1 006
10
222
4-chloro-3-methylphenol-d2
1086
164
0 930-0 943
10
322
4-chloro-3-methylphenol
1091
222
0 998-1 003
10
221
2,4 6-trichlorophenol-dj
1162
164
0 994-1 005
10
321
2,4,6-trichlorophenol
1165
221
0 998-1 004
10
531
2,4,5-trichlorophenol"
1170
164
0 996-1 016
10
530
2,3.6-tnchlorophenol*
1195
164
1 016-1 140
10
259
2,4-dimtrophenol-dj
1323
164
1 127-1 149
50
359
2,4-dimtrophenol
1325
259
1 000-1 005
50
258
4-nitrophenol-d4
1349
164
1 147-1 175
50
358
4-nitrophenol
1354
258
0 997-1 006
50
260
2-methyl-4,6-dimtrophenol-d2
1433
164
1 216-1 249
20
360
2-methyl-4,6-dinitrophenol
1435
260
1 000-1 002
20
264
pentachlorophenol-,3CB
1559
164
1 320-1 363
50
364
pentachlorophenol
1561
264
0 998-1 002
50
(1) Reference numbers beginning with 0 1 or 5 indicate a pollutant quantified by the internal standard method, reference numbers beginning with 2 or 6
indicate a labeled compound quantified by the internal standard method, reference numbers beginning with 3 or 7 indicate a pollutant quantified by
isotope dilution
(2) This is a minimum level at which the entire GC/MS system must give recognizable mass spectra (background corrected) and acceptable calibration
points
' specification denved from related compound
Column 30 ± 2 m x 0 25 ± 0 02 mm id 94% methyl 4% phenyl, t % vinyl bonded phase (used silica capillary
Temperature prog am 5 mm at 30°C 30 - 250°C or until pentachlorophenol elutes
Gas velocity 30 ± cm/sec
5
-------
4 SAFETY
4 1 The toxicity or carcinogenicity of each compound or
reagent used in this method has not been precisely
determined, however, each chemical compound
should be treated as a potential health hazard
Exposure to these compounds should be reduced to
the lowest possible level The laboratory is responsi-
ble for maintaining a current awareness file of OSHA
regulations regarding the safe handling of the
chemicals specified in this method A reference file
of data handling sheets should also be made
available to all personnel involved in these analyses
Additional information on laboratory safety can be
found in references 2-4
4 2 The following compounds covered by this method
have been tentatively classified as known or
suspected human or mammalian carcinogens ben-
zo(a)anthracene, 3,3'-dichlorobenzidine, benzo(a)py-
rene, dibenzo(a,h)anthracene, N-nitrosodimethyla-
mine, and beta-naphthylamine Primary standards of
these compounds shall be prepared in a hood, and a
NIOSH/MESA approved toxic gas respirator should
be worn when high concentrations are handled
5 APPARATUS AND MATERIALS
51 Sampling equipment for discrete or composite
sampling
5 1 1 Sample bottle, amber glass, 1 1 liters minimum If
amber bottles are not available, samples shall be pro-
tected from light Bottles are detergent water
washed, then solvent rinsed or baked at 450 °C for
one hour minumum before use
5 1 2 Bottle caps—threaded to fit sample bottles Caps are
lined with Teflon Aluminum foil may be substituted if
the sample is not corrosive Liners are detergent
water washed, then reagent water (section 6 5) and
solvent rinsed, and baked at approximately 200°C
for one hour minumum before use
5 1 3 Compositing equipment—automatic or manual com-
positing system incorporating glass containers for
collection of a minimum 1 1 liters Sample containers
are kept at 0 to 4 "C during sampling Glass or Teflon
tubing only shall be used If the sampler uses a
peristaltic pump, a minimum length of compressible
silicone rubber tubing may be used in the pump only
Before use, the tubing is thoroughly rinsed with
methanol, followed by repeated rinsings with reagent
water (section 6 5) to minimize sample contamina-
tion An integrating flow meter is used to collect pro-
portional composite samples
5 2 Continuous liquid-liquid extractor—Teflon or glass
connecting joints and stopcocks without lubrication
(Hershberg-Wolf Extractor) one liter capacity, Ace
Glass 6841-10, or equivalent
5 3 Drying column—15 to 20 mm i d Pyrex chromato-
graphic column equipped with coarse glass frit or
glass wool plug
5 4 Kuderna-Danish (K-D) apparatus
54 1 Concentrator tube— 10mL, graduated (Kontes
K-570050-1025, or equivalent) with calibration
verified Ground glass stopper (size 19/22 joint) is
used to prevent evaporation of extracts
5 4 2 Evaporation flask—500 mL (Kontes K-570001 -0500,
or equivalent), attached to concentrator tube with
springs (Kontes K-662750-0012)
5 43 Snyder column—three ball macro (Kontes
K-503000-0232, or equivalent)
5 4 4 Snyder column —two ball micro (Kontes
K-469002-0219, or equivalent)
5 4 5 Boiling chips—approx 10/40 mesh, extracted with
methylene chloride and baked at 450°C for one hr
minimum
5 5 Water bath—heated, with concentric ring cover,
capable of temperature control (± 2 °C), installed in a
fume hood
5 6 Sample vials—amber glass, 2-5 mL with Teflon-lined
screw cap
5 7 Analytical balance—capable of weighing 0 1 mg
5 8 Gas chromatograph—shall have splitless or on-
column injection port for capillary column,
temperature program with 30 °C hold, and shall meet
all the performance specifications in section 12
581 Column—30 ±5 m x 0 25 ±0 02 mm i d 5% phenyl,
94% methyl, 1 % vinyl silicone bonded phase fused
silica capillary column (J & W DB-5, or equivalent)
5 9 Mass spectrometer—70 eV electron impact ioniza-
tion, shall repetitively scan from 35 to 450 amu in
0 95 to 1 00 second and shall produce a unit resolu-
tion (valleys between m/z 441-442 less than 10 per-
cent of the height of the 441 peak), background cor-
rected mass spectrum from 50 ng decafluoro-
triphenylphosphine (DFTPP) introduced through the
GC inlet The spectrum shall meet the mass-intensity
criteria in table 5 (reference 5) The mass spec-
trometer shall be interfaced to the GC such that the
end of the capillary column terminates within one
centimeter of the ion source but does not intercept
the electron or ion beams All portions of the column
which connect the GC to the ion source shall remain
at or above the column temperature during analysis
to preclude condensation of less volatile com-
P0""dS TABLE 5
DFTPP Mass-intensity Specifications
MASS INTENSITY REQUIRED
51
8-82 percent of mass 198
68
< 2 percent of mass 69
69
11-91 percent of mass 198
70
<2 percent of mass 69
127
32-59 percent of mass 198
198
base peak, 100 percent abundance
199
4-9 percent of mass 198
275
11 -30 percent of mass 198
441
44-110 percent of mass 443
442
30-86 percent of mass 198
443
14-24 percent of mass 442
5 10
Data system—shall collect and record MS data, store
mass intensity data in spectral libraries, process
GC/MS data, generate reports, and shall compute
and record response factors
5 10 1 Data acquisition—mass spectra shall be collected
continuously throughout the analysis and stored on a
mass storage device
6
-------
0 2
03
04
6
6 1
62
63
64
6 5
66
6 7
Mass spectral libraries—user created libraries con-
taining mass spectra obtained from analysis of
authentic standards shall be employed to reverse
search GC/MS runs for the compounds of interest
(section 7 2)
Data processing—the data system shall be used to
search, locate, identify, and quantify the compounds
of interest in each GC/MS analysis Software routines
shall be employed to compute retention times and
peak areas Displays of spectra, mass chromato-
grams, and library comparisons are required to verify
results
Response factors and multipoint calibrations—the
data system shall be used to record and maintain
lists ot response factors (response ratios for isotope
dilution) and multipoint calibration curves (section 7)
Computations of relative standard deviation (coeffi-
cient of variation) are useful for testing calibration
linearity Statistics on initial (section 8 4) and on-
going (section 12 7) performance shall be computed
and maintained
REAGENTS AND STANDARDS
Sodium hydroxide—reagent grade, 6N in reagent
water
Sulfuric acid—reagent grade, 6N in reagent water
Sodium sulfa'e—reagent grade, granular anhydrous,
rinsed with methylene chloride (20 mUg) and condi-
tioned at 450°C for one hour minimum
Methylene chloride—distilled in glass (Burdick and
Jackson, or equivalent)
Reagent water—water in which the compounds of in-
te'est and interfering compounds are not detected by
th's method
Standard solutions—purchased as solutions or mix-
tures with certification to their purity, concentration,
and authenticity, or prepared from materials of
known purity and composition If compound purity is
96 percent or greater, the weight may be used
without correction to compute the concentration of
the standard When not being used, standards are
stored in the dark at -20 to -10°C in screw-
capped vials with Teflon-lined lids A mark is placed
on the vial at the level of the solution so that solvent
evaporation loss can be detected The vials are
brought to room temperature prior to use Any
precipitate is redissolved and solvent is added if sol-
vent loss has occurred
Preparation of stock solutions—prepare in
methylene chloride, benzene, p-dioxane, or a mixture
of these solvents per the steps below Observe the
sa'ety precautions given in section 4 The large
number of labeled and unlabeled acid, base/neutral,
and Appendix C compounds used for combined
ca ibration (section 7) and calibration verification
(12 5) require high concentrations (approx 40
mg/mL) when individual stock solutions are
prepared, so that dilutions of mixtures will permit
calibration with all compounds in a single set of solu-
tions The working range for most compounds is
10-200 MQ/mL Compounds with a reduced MS
response may be prepared at higher concentrations
6 7 1 Dissolve an appropriate amount of assayed
reference material in a suitable solvent For example,
weigh 400 mg naphthalene in a 10 mL ground glass
stoppered volumetric flask and fill to the mark with
benzene After the naphthalene is completely
dissolved, transfer the solution to a 15 mL vial with
Teflon-lined cap
6 7 2 Stock standard solutions should be checked foi
signs of degradation prior to the preparation of
calibration or performance test standards Quality
control check samples that can be used to determine
the accuracy of calibration standards are available
from the US Environmental Protection Agency,
Environmental Monitoring and Support Laboratory,
Cincinnati, Ohio 45268
6 7 3 Stock standard solutions shall be replaced after six
months, or sooner if comparison with quality control
check samples indicates a change in concentration
6 8 Labeled compound spiking solution—from stock
standard solutions prepared as above, or from mix-
tures, prepare the spiking solution at a concentration
of 200 Mg/mL, or at a concentration appropriate to
the MS response of each compound
6 9 Secondary standards—using stock solutions (sec-
tion 6 7), prepare a secondary standard containing all
of the compounds in tables 1 and 2 at a concentra-
tion of 400 Mg/mL, or higher concentration ap-
propriate to the MS response of the compound
6 10 Internal standard solution—prepare 2,2'-difluoro-
biphenyl (DFB) at a concentration of 10 mg/mL in
benzene
6 11 DFTPP solution—prepare at 50 Mg/mL in acetone
6 12 Solutions for obtaining authentic mass spectra (sec-
tion 7 2)—prepare mixtures of compounds at con-
centrations which will assure authentic spectra are
obtained for storage in libraries
6 13 Calibration solutions—combine 0 5 mL of the solu-
tion in section 6 8 with 25, 50, 125, 250, and 500 mL
of the solution in section 6 9 and bring to 1 00 mL
total volume each This will produce calibration solu-
tions of nominal 10, 20, 50, 100 and 200 Mg/mL of
the pollutants and a constant nominal 100M9/mL of
the labeled compounds Spike each solution with 10
mL of the internal standard solution (section 6 10)
These solutions permit the relative response (labeled
to unlabeled) to be measured as a function of con-
centration (section 7 4)
6 14 Precision and recovery standard—used for deter-
mination ot initial (section 8 2) and on-going (section
12 7) precision and recovery This solution shall con-
tain the pollutants and labeled compounds at a
nominal concentration of 100 Mg/mL
6 15 Stability of solutions—all standard solutions (sections
6 8-6 14) shall be analyzed within 48 hours of
preparation and on a monthly basis thereafter for
signs of degradation Standards will remain accep-
table if the peak area at the quantitation mass relative
to the DFB internal standard remains within ± 15 per-
cent of the area obtained in the initial analysis of the
standard
7
-------
7 CALIBRATION
7 1 Assemble the GC/MS and establish operating condi-
tions in table 3 Analyze standards per the procedure
in section 11 to demonstrate that the analytical
system meets the detection limits in tables 3 and 4,
and the mass-intensity criteria in table 5 for 50 ng
DFTPP
7 2 Mass spectral libraries—detection and identification
of compounds of interest are dependent upon spec-
tra stored in user created libraries
7 2 1 Obtain a mass spectrum of each pollutant, labeled
compound, and the internal standard by analyzing an
authentic standard either singly or as part of a mix-
ture in which there is no interference between closely
eluted components That only a single compound is
present is determined by examination of the spec-
trum Fragments not attributable to the compound
under study indicate the presence of an interfering
compound
7 2 2 Adjust the analytical conditions and scan rate (for this
test only) to produce an undistorted spectrum at the
GC peak maximum An undistorted spectrum will
usually be obtained if five complete spectra are col-
lected across the upper half of the GC peak Soft-
ware algorithms designed to "enhance" the spec-
trum may eliminate distortion, but may also eliminate
authentic masses or introduce other distortion
7 2 3 The authentic reference spectrum is obtained under
DFTPP tuning conditions (section 7 1 and table 5) to
normalize it to spectra from other instruments
7 2 4 The spectrum is edited by saving the 5 most intense
mass spectral peaks and all other mass spectral
peaks greater than 10 percent of the base peak This
edited spectrum is stored for reverse search and for
compound confirmation
7 3 Analytical range—demonstrate that 20 ng anthra-
cene or phenanthrene produces an area at m/z 178
approx one-tenth that required to exceed the linear
range of the system The exact value must be deter-
mined by experience for each instrument It is used
to match the calibration range of the instrument to the
analytical range and detection limits required, and to
diagnose instrument sensitivity problems (section
15 4) The 20 uglmL calibration standard (section
6 13) can be used to demonstrate this performance
7 31 Polar compound detection—demonstrate that
unlabeled pentachlorophenol and benzidine are
detectable at the 50 jug/mL level (per all criteria in
section 13) The 50 M9/mL calibration standard (sec-
tion 6 13) can be used to demonstrate this perfor-
mance
7 4 Calibration with isotope dilution—isotope dilution is
used when 1) labeled compounds are available, 2) in-
terferences do not preclude its use, and 3) the quan-
titation m/z (tables 6 and 7) extracted ion current pro-
file (EICP) area for the compound is in the calibration
range If any of these conditions preclude isotope
dilution, the internal standard method (section 7 5) is
used
TABLE 6
Base/Neutral Extractable Compound
Characteristic Masses
LABELED
PRIMARY
COMPOUND
ANALOG
M/Z'S
acenaphthene
dio
154/164
acenaphthylene
da
1 52/160
anthracene
dio
178/188
benzidine
d«
184/192
benzo(a)anlhracene
di2
228/240
benzo(b)tluoranthene
di2
252/264
benzo(k)fluoranthene
di2
252/264
benzo(a)pyrene
di2
252/264
benzo(ghi)perylene
di2
276/288
biphenyl
dio
154/164
bis(2-chloroethyl) ether
da
93/101
bis(2-chloroethoxy) methane
93
bis(2-chloroisopropyl) ether
d,2
121/131
bis(2-ethylhexyl) phthalale
d«
149/153
4-bromophenyl phenyl ether
248
butyl benzyl phthaiate
149
n-Cio
d22
55/66
n-Ci2
d26
55/66
n-C t4
55
n-C ia
dj<
55/66
n-Cia
55
n-C2D
d«2
55/66
n-C22
55
n-C24
dso
55/66
n-C2s
55
n-C2B
55
n-Cso
d{2
55/66
carbazole
de
167/175
2-chloronaphthalene
d7
162/169
4-chlorophenyl phenyl ether
d5
204/209
chrysene
d 12
228/240
p-cymene
di4
119/1 30
dibenzo(a,h)anthracene
278
dibenzofuran
da
168/1 76
dibenzothiophene
da
184/192
di-n-butyl phthaiate
d<
1 49/1 53
1,2-dichlorobenzene
d«
146/152
1,3-dichlorobenzene
d.
1 46/1 52
1,4-dichlorobenzene
d.
1 46/1 52
3,3'-dichlorobenzidine
da
252/258
diethyl phthaiate
d<
149/153
2,4-dimethylphenol
di
122/125
dimethyl phthaiate
d<
163/167
2,4-dinitrotoluene
d3
165/168
2.6-dinitrotoluene
ds
165/167
di-n-octyl phthaiate
d4
149/153
diphenylamine
dio
169/179
diphenyl ether
dio
1 70/180
1,2-diphenylhydrazine'
dio
77/82
tluoranlhene
dio
202/212
fluorene
dio
166/176
hexachlorobenzene
,3Ca
284/292
hexachlorobutadiene
,3C<
225/231
hexachloroethane
,3C
201/204
hexachlorocyclopentadiene
,3C,
237/241
ideno(1,2,3-cd)pyrene
276
isophorone
da
82/88
naphthalene
da
128/136
beta-naphthylamine
dj
143/150
nitrobenzene
d5
123/128
N-nitrosodimethylamme
74
N-nitrosodi-n-propylamine
70
N-nitrosodiphenylamme''
ds
169/175
phenanthrene
dio
178/188
8
-------
TABLE 6 (Continued)
Base/Neutral Extractable Compound
Characteristic Masses
LABELED
PRIMARY
COMPOUND
ANALOG
M/Z'S
phenol
d5
94/71
alpha-picoline
d7
93/100
pyiene
dio
202/212
styrene
d5
104/109
alpha-lerpineol
d3
59/62
1,2,3-trichlorobenzene
d3
180/183
1,2,4-trichlorobenzene
d3
180/183
"detected as azobenzene
' 'delected as diphenylamme
TABLE 7
Acid Extractable Compound
Characteristic Masses
LABELED
PRIMARY
COMPOUND
ANALOG
M/Z'S
4-chloro-3-methvlphenol
d2
107/109
2-chlorophenol
d4
128/132
2,4-dichlorophenol
d3
162/167
2,4-dmitrophenol
d3
184/187
2-methyl-4,6-din tropheaol
d2
198/200
2-nitrophenol
d.
139/143
4-nitrophenol
d»
139/143
pentachlorophenol
,3Ca
266/272
2,3,6-trichlorophenol
d2
196/200
2,4,5-trichlorophenol
d2
196/200
2,4,6-trichloroph9nol
d2
196/200
7 4 1 A calibration curve encompassing the concentration
range is prepa'ed tor each compound determined
The relative response (pollutant to labeled) vs con-
centration in standard solutions is plotted or com-
puted using a linear regression The example in
figure 1 shows a calibration curve for phenol using
i i i i i i
T 1 1 1 1 r~
2 10 20 50 100 200
CONCENTRATION (gg/mL)
FIGURE 1 Relative Response Calibration Curve
for Phenol. The Dotted Lines Enclose a ± lO Per-
cent Error Window
phenol-ds as the isotopic diluent Also shown are the
±10 percent error limits (dotted lines) Relative
Response (RR) is determined according to the pro-
cedures described below A minumum of five data
points are employed for calibration
7 4 2 The relative response of a pollutant to its labeled
analog is determined from isotope ratio values com-
puted from acquired data Three isotope ratios are
used in this process
Rx= the isotope ratio measured for the pure
pollutant
Ry= the isotope ratio measured for the labeled
compound
Rm= the isotope ratio of an analytical mixture of
pollutant and labeled compounds
The mlz's are selected such that Rx > Ry If Rm is not
between 2Ry and 0 5RX, the method does not apply
and the sample is analyzed by the internal standard
method (section 7 5)
7 4 3 Capillary columns usually separate the pollutant-
labeled pair, with the labeled compound eluted first
(figure 2) For this case,
D _ [area m,/z]
"x •
1
at the retention time of the pollutant (RT2)
Ry = ^
[area m2/z]
at the retention time of the labeled compound (RT,)
p _ [area m,/z (at RT2)]
nm — .
[area m2/z (at RT,)]
as measured in the mixture of the pollutant and la-
beled compounds (figure 2), and RR = Rm
AREA AT
MJZ
AREA AT
M,/Z
RT,
FIGURE 2 Extracted Ion Current Profiles for
Chromatographically Resolved Labeled (m,/z)
and Unlabeled (m,/z) Pairs.
7 4 4 Special precautions are taken when the pollutant-
labeled pair is not separated, or when another la-
beled compound with interfering spectral masses
overlaps the pollutant (a case which can occur with
isomeric compounds) In this case, it is necessary to
determine the respective contributions of the pollu-
tant and labeled compounds to the respective EICP
areas If the peaks are separated well enough to per-
mit the data system or operator to remove the con-
tributions of the compounds to each other, the equa-
tions in section 7 4 3 apply This usually occurs
when the height of the valley between the two GC
peaks at the same m/z is less than 10 percent of the
height of the shorter of the two peaks If significant
9
-------
GC and spectral overlap occur, RR is computed us-
ing the following equation
pp _ (Ry~ RmX^x"*" 1 )
(Rm— RxKRy+1)
where Rx is measured as shown in figure 3A, Ry is
measured as shown in figure 3B, and Rm is
measured as shown in figure 3C For the example,
R _ 46100 _ 9 644
Ry =
4780
_ 2650
43600
49200
. = 0 0608
= 1 019
745
48300
RR =1 114
To calibrate the analytical system by isotope dilution,
analyze a 1 OfiL aliquot of each of the calibration
standards (section 6 13) using the procedure in sec-
tion 11 Compute the RR at each concentration
AREA = 4780
AREA = 46100
(3B)
AREA = 2650
AREA = 43600
AREA = 48300
AREA = 49200
7 4 6
75
FIGURE 3 Extracted Ion Current Profiles lor (3A)
Unlabeled Compound, (3B) Labeled Com-
pound, and (3C) Equal Mixture of Unlabeled
and Labeled Compounds.
Linearity—if the ratio of relative response to concen-
tration for any compound is constant (less than 20
percent coefficient of variation) over the 5 point
calibration range, an averaged relative response/
concentration ratio may be used for that compound,
otherwise, the complete calibration curve for that
compound shall be used over the 5 point calibration
range
Calibration by internal standard—used when criteria
for isotope dilution (section 7 4) cannot be met The
internal standard to be used for both acid and
base/neutral analyses is 2,2'-difluorobiphenyl The
internal standard method is also applied to deter-
mination of compounds having no labeled analog,
and to measurement of labeled compounds for intra-
laboratory statistics (sections 8 4 and 12 7 4)
7 5 1 Response factors—calibration requires the deter-
mination of response factors (RF) which are defined
by the following equation
RF = (As x C|s) , where
(A|S X Cs),
As is the area at the characteristic mass for the com-
pound in the daily standard
A,s is the area of the characteristic mass for the inter-
nal standard
CIS is the concentration of the internal standard
(ftg/mL)
Cs is the concentration of the compound in the daily
standard (ug/mL)
7 5 11 The response factor is determined for at least five
concentrations appropriate to the response of each
compound (section 6 13), nominally, 10, 20, 50,100,
and 200 /ug/mL The amount of internal standard
added to each extract is the same (100 /ug/mL) so
that CIS remains constant The RF is plotted vs con-
centration for each compound in the standard (Cg) to
produce a calibration curve
7 5 12 Linearity—if the response factor (RF) for any com-
pound is constant (less than 35 percent coefficient of
variation) over the 5 point calibration range, an
averaged response factor may be used for that com-
pound, otherwise, the complete calibration curve for
that compound shall be used over the 5 point range
7 6 Combined calibration—by using calibration solutions
(section 6 13) containing the pollutants, labeled com-
pounds, and the internal standard, a single set of
analyses can be used to produce calibration curves
for the isotope dilution and internal standard
methods These curves are verified each shift (sec-
tion 12 5) by analyzing the 100/ug/mL calibration
standard (section 6 13) Recalibration is required
only if calibration verification (section 12 5) criteria
cannot be met
8 QUALITY ASSURANCE/QUALITY CONTROL
8 1 Each laboratory that uses this method is required to
operate a formal quality assurance program The
minimum requirements of this program consist of an
initial demonstration of laboratory capability, analysis
of samples spiked with labeled compounds to
evaluate and document data quality, and analysis of
standards and blanks as tests of continued perfor-
mance Laboratory performance is compared to
established performance criteria to determine if the
results of analyses meet the performance character-
istics of the method
8 1 1 The analyst shall make an initial demonstration of the
ability to generate acceptable accuracy and preci-
sion with this method This ability is established as
described in section 8 2
8 1 2 The analyst is permitted to modify this method to im-
prove separations or lower the costs of
measurements, provided all performance specifica-
tions are met Each time a modification is made to the
method, the analyst is required to repeat the pro-
cedure in section 8 2 to demonstrate method perfor-
mance
lO
-------
8 1 3 Analyses ol blanks are required to demonstrate
freedom from contamination The procedures and
criteria for analysis of a blank are described in sec-
tions 8 5
8 1 4 The laboratory shall spike all samples with labeled
compounds to monitor method performance This
test is described in section 8 3 When results of these
spikes indicate atypical method performance for
samples, the samples are diluted to bring method
performance within acceptable limits (section 15)
815 Tne laboratory shall, on an on-going basis,
demonstrate through calibration verification and the
analysis of the precision and recovery standard (sec-
tion 6 14) that the analysis system is in control
These procedures are described in sections 12 1,
12 5, and 12 7
8 1 6 The laboratory shall maintain records to define the
quality of data that is generated Development of ac-
curacy statements is described in section 8 4
8 2 Initial precision and accuracy—to establish the ability
to generate acceptable precision and accuracy, the
analyst shall perform the following operations
8 2 1 Extract, concentrate, and analyze two sets of four
one-liter aliquots (8 aliquots total) of the precision and
recovery standard (section 6 14) according to the
procedure in section 10
8 2 2 Using results of the first seJ_of four analyses, com-
pute the average recovery (X) in /*g/mL and the stan-
dard deviation of the recovery (s) in /tg/mL for each
compound, by isotope dilution for pollutants with a
labeled analog, and by internal standard for labeled
compounds and pollutants with no labeled analog
8 2 3 For each compound, compare s and X with the cor-
responding limits for initial precision and accuracy in
table 8 If s and X for all compounds meet the accep-
tance criteria, system performance is acceptable and
analysis of blanks and samples may begin If,
however, any individual s exceeds the precision limit
or any individual X falls outside the range for ac-
curacy, system performance is unacceptable for that
compound NOTE The large number of compounds
in table 8 present a substantial probability that one or
more will fail one of the acceptance criteria when all
compounds are analyzed To determine if the
analytical system is out of control, or if the failure can
be attributed to probability, proceed as follows
8 2 4 Using the results of the second set of four analyses,
compute s and ^ for only those compounds which
failed the test of the first set of four analyses (section
TABLE 8
Acceptance Criteria for Performance Tests
ACCEPTANCE CRITERIA
INITIAL
LABELED
CALIBRA-
PRECISION
COMPOUND
TION
AND ACCURACY
RECOVERY
VERIFI-
ON-GOING
EGD
SECTION 8 2 3
SECTION 8 3
CATION
ACCURACY
NO
(UU/L)
AND 14 2
SECTION 12 5 SECTION 12 7
(V
COMPOUND
s
X
P<%)
(UO/mL)
R (mq/L)
30"
acenaphlhene
21
79-134
80 - 125
72 - 144
20
acenaphthene-dto
38
38-147
20 - 270
71-141
30-180
377
acenaphthylene
38
69 -186
60 - 166
61 - 207
277
acenaphthyiene-da
31
39-146
23 - 239
66 -152
33-168
378
anthracene
41
58-174
60 -168
50- 199
278
anthracene-d,0
49
31 - 194
14-419
58-171
23 - 242
305
benzidine
119
16-518
34 - 296
11-672
205
benzidine-da
269
ns - ns
ns - ns
ns - ns
ns - ns
372
benzo(a)anthracene
20
65 -168
70 -142
62-176
272
benzo(a)anth racene-d 12
41
25 - 298
12 - 605
28 - 357
22 - 329
374
benzo(b)fluoranihene
183
32 -545
61-164
20 - ns
274
benzo(b)fluoranthene-d,j
168
11-577
ns - ns
14 - ns
ns - ns
375
benzo(k)fluoranthene
26
59-143
13 - ns
53-155
275
benzo(k)fluoranthene-d 12
114
15-514
ns - ns
13 - ns
ns - 685
373
benzo(a)pyrene
26
62-195
78 -129
59 - 206
273
benzo(a)pyrene-d,2
24
35-181
21 -290
12 - ns
32-194
379
benzo(ghi)perylene
21
72-160
69 -145
58-168
279
benzo(ghi)perylene-d, 2
45
29 - 268
14 - 529
13 - ns
25 - 303
712
biphenyl (Appendix C)
41
75-148
58-171
62-176
612
biphenyl-d,0
43
28-165
ns - ns
52-192
17-267
318
bis(2-chloroethyl) ether
34
55-196
61-164
50-213
218
bis(2-chloroethyl) ether-d9
33
29-196
15-372
52 -194
25 - 222
043
bis(2-chlorceihyoxy) methane'
27
43-153
44 - 228
39-166
342
bis(2-chloroisopropyl) ether
17
81-138
67-148
77-145
242
bis(2-chloroisopropyl) ether-d12
27
35 - 149
20 - 260
44 - 229
30-169
366
bis(2-ethylhexyl) phthalate
31
69 - 220
76-131
64 - 232
266
bis(2-ethylhexyl) phthalate-d<
29
32 - 205
18 - 364
43 - 232
28 - 224
041
4-bromophenyl phenyl ether*
44
44-140
52 - 193
35-172
067
butyl benzyl phthalate*
31
37-183
22 - 450
35-195
11
-------
TABLE 8 (Continued)
Acceptance Criteria for Performance Tests
ACCEPTANCE CRITERIA
EGD
NO
INITIAL
PRECISION
AND ACCURACY
SECTION 8 2 3
(PQ/L)
LABELED
COMPOUND
RECOVERY
SECTION 8 3
AND 14 2
CALIBRA-
TION
VERIFI- ON-GOING
CATION ACCURACY
SECTION 12 5 SECTION 12 7
(1)
COMPOUND
s
X
P<%)
(UO/mL)
R (UO/L)
717
n-Cio (Appendix C)
51
24-195
42 - 235
19-237
617
n-Cio-d22
70
ns - 298
ns - ns
44 - 227
ns - 404
706
n-Ci2 (Appendix C)
74
35 - 369
60 - 166
29-424
606
n-C 12-028
53
ns - 331
ns - ns
41 - 242
ns - 408
518
n-Cn (Appendix C)'
109
ns - 985
37 - 268
ns - ns
719
n-C,6 (Appendix C)*
33
80- 162
72-138
71-181
619
rv-Ci8-d3<
46
37-162
18-308
54 -186
28 - 202
520
n-Cis (Appendix C)"
39
42-131
40 - 249
35-167
721
n-C2o (Appendix C)
59
53 - 263
54 - 184
46-301
621
n-Cpo-C. ?
34
34-172
19-306
62 -162
29 -198
522
n-C22 (Appendix C)"
31
41 - 184
40 - 249
39-195
723
n-C21 (Appendix C)
11
80-139
65-154
78-142
623
n-C2»-d5o
28
27-211
15-376
50- 199
25 - 229
524
n-C26 (Appendix C)*
35
35-193
26 - 392
31-212
525
n-C2» (Appendix C)*
35
35-193
26 - 392
31 -212
726
n-C30 (Appendix C)
32
61 - 200
66 -152
56-215
626
n-C3o-de2
41
27- 242
13-479
24 -423
23-274
528
carbazole (4c)*
38
36-165
44 -227
31-188
320
2-chloronaphthalene
100
46-357
58-171
35-442
220
2-chloronaphthalene-dr
41
30-168
15-324
72-139
24 - 204
322
4-chloro-3-methylphenol
37
76-131
85 -115
62 -159
222
4-chloro-3-methytphenol-d2
111
30-174
ns - 613
68-147
14-314
324
2-chlorophenol
13
79- 135
78-129
76-138
224
2-chlorophenol-dj
24
36- 162
23 - 255
55-180
33-176
340
4-chlorophenyl phenyl ether
42
75-166
71-142
63-194
240
4-chlorophenyl phenyl ether-d5
52
40-161
19-325
57-175
29-212
376
chrysene
51
59-186
70-142
48- 221
276
chrysene-di2
69
33-219
13-512
24 -411
23 - 290
713
p-cymene (Appendix C)
18
76-140
79-127
72-147
613
p-cymene-du
67
ns - 359
ns - ns
66 - 152
ns - 468
082
dibenzo(a,h)anthracene'
55
23 - 299
13-761
19-340
705
dibenzofuran (Appendix C)
20
85-136
73-136
79 - 1 46
605
dibenzofuran-ds
31
47-136
28 - 220
66 - 150
39 -160
704
dibenzothiophene (Synluel)
31
79-150
72-140
70 - 168
604
dibenzothiophene-d6
31
48-130
29-215
69-145
40-156
368
di-n-butyl phthalate
15
76-165
71 - 142
74 -169
268
di-n-butyl phthalate-da
23
23-195
1 3 - 346
52-192
22 - 209
325
1,2-dichlorobenzene
17
73-146
74-135
70-152
225
1,2-dichlorobenzene-d)
35
14-212
ns - 494
61-164
11-247
326
1,3-dichlorobenzene
43
63 - 201
65 - 1 54
55 - 225
226
1.3-dichlorobenzejie-d4
48
13-203
ns - 550
52-192
ns - 260
327
1,4-dichlorobenzene
42
61 - 194
62-161
53-219
227
1,4-dichlorobenzene-d»
48
15-193
ns - 474
65 -153
11 - 245
328
3,3-dichlorobenzidine
26
68 - 1 74
77-130
64 - 185
228
3,3'-dichlorobenzidine-da
80
ns - 562
ns - ns
18 - 558
ns - ns
331
2,4-dichlorophenol
12
85-131
67 -149
83-135
231
2,4-dichlorophenol-d3
28
38-164
24 - 260
64-157
34 - 182
370
diethyl phthalate
44
75 - 196
74-135
65-222
270
diethyl phthalate-d4
78
ns - 260
ns - ns
47-211
ns - ns
334
2,4-dimethylphenol
13
62-153
67-150
60 - 156
234
2,4-dimethylphenol-d3
22
15-228
ns - 449
58-172
14 - 242
3/1
dimethyl phthalate
36
74-188
73-137
67 - 207
271
dimethyl phthalale-d«
108
ns - 640
ns - ns
50 - 201
ns - ns
359
2,4-dinitrophenol
18
72 - 134
75-133
68-141
259
2,4-dinitrophenol-
-------
TABLE 8 (Continued)
Acceptance Criteria lor Performance Tests
ACCEPTANCE CRITERIA
EGD
NO
INITIAL
PRECISION
AND ACCURACY
SECTION 8 2 3
(UO/D
LABELED
COMPOUND
RECOVERY
SECTION 0 3
AND 14 2
CALIBRA-
TION
VERIFI- ON-GOING
CATION ACCURACY
SECTION 12 5 SECTION 12 7
(1)
COMPOUND
s
X
P(%)
(ug/mL)
R (MQ/L)
269
di-n-octy phthalate-d<
46
12 - 383
ns - ns
21 -467
10-433
707
diphenylamine (Appendix C)
45
58 - 205
57 -1 76
51 -231
607
diphenylamine-dio
42
27 - 206
11 - 488
59 -169
21 - 249
708 diphenyl ether (Appendix C)
19
82 -136
83 -120
77-144
608
diphenyl elher-dio
37
36-155
19-281
77-129
29 - 186
337
1,2-diphenylhydrazine
73
49 - 308
75 -134
40 - 360
237
1,2-diphenylhydrazine-dio
35
31-173
17-316
58-174
26 - 200
339
fluoranthene
33
71 -177
67 -149
64 - 194
239
fluoranthene-dio
35
36-161
20-278
47-215
30-187
380
fluorene
29
81 -132
74 -135
70-151
280
lluorene-dio
43
51 -131
27 - 238
61 -164
38-172
309
hexachlorobenzene
16
90-124
78 -128
85-132
209
hexachlorobenzene-13C6
81
36 - 228
13-595
38 - 265
23 - 321
352
hexachlorobutadiene
56
51 - 251
74-135
43-287
252
hexachlorobutadiene-13C«
63
ns - 316
ns - ns
68 -1 48
ns - 413
312
hexachloi oethane
227
21 - ns
71-141
13 - ns
212
hexachloi oethane-'3C,
77
ns - 400
ns - ns
47-212
ns - 563
353
hexachloi ocyclopentadiene
15
69-144
77-129
67-148
2E3
hexachloi ocyclopentadiene-,3C<
60
ns - ns
ns - ns
47-211
ns - ns
083
ideno(1,2,3-cd)pryene*
55
23 - 299
13-761
19 - 340
354
isophorone
25
76- 156
70-142
70 - 168
254
isophorone-da
23
49-133
33 -193
52 - 194
44-147
360
2-methyl-4,6-dinitrophenol
19
77-133
69 -1 45
72-142
260
2-methyl-4,6-dinitrophenol-d2
64
36- 247
16-527
56 -1 77
28 - 307
355
naphthalene
20
80-139
73-137
75-149
255
naphthalene-do
39
28-157
14 - 305
71-141
22 - 192
702
beta-naphthylamine (Appendix C)
49
10 - ns
39 - 256
ns - ns
602
beta-naphthylamine-d7
33
ns - ns
ns - ns
44 -230
ns - ns
356
nitrobenzene
25
69-161
85 -115
65-169
256
mtrobenzene-d5
28
18-265
ns - ns
46-219
15-314
357
2-nitrophenol
15
78-140
77-129
75-145
257
2-nitrophenol-d4
23
41-145
27-217
61-163
37-158
358
4-nitropherol
42
62-146
55-183
51-175
258
4-nitrophenol-d,
188
14 - 398
ns - ns
35 - 287
ns - ns
061
N-nitrosodimethylamine*
198
21 -472
40 - 249
12 - ns
063
N-nitrosodi-n-propylamine'
198
21 - 472
40 - 249
12 - ns
362
N-nitrosodiphenylamine
45
65-142
68 -148
53-173
262
N-nitrosodiphenylamme-d6
37
54 - 126
26 - 256
59-170
40-166
364
pentachloiophenol
21
76-140
77-130
71-150
264
pentachloiophenol-'3C6
49
37-212
18-412
42 -237
29 - 254
381
phenanthrene
13
93 - 119
75-133
87-126
281
phenanthrene-dio
40
45-130
24 -241
67-149
34 - 168
365
phenol
36
77-127
65-155
62-154
26b
phenol-d5
161
21 -210
ns - ns
48 - 208
ns - ns
703
alpha-pico.me (Synfuel)
36
59-149
60-165
50 - 1 74
603
alpha-pico ine-dr
138
11 - 380
ns - ns
31 -324
ns - 608
384
pyrene
19
76-152
76-132
72-159
284
pyrene-dio
29
32-176
18 - 303
48-210
28 - 196
710
styrene (Aopendix C)
42
53-221
65-153
48 - 244
610
styrene-d5
49
ns - 281
ns - ns
44 - 228
ns - 348
709
alpha-terpneol (Appendix C)
44
42- 234
54 -186
38 - 258
609
alpha-terpneol-d3
48
22-292
ns - 672
20 - 502
18-339
529
1,2,3-trichlorobenzene (4c)"
69
15-229
60-167
11 - 297
308
1,2.4-trichlorobenzene
19
82 - 136
78-128
77-144
208
1,2,4-trichlorobenzene-d3
57
15-212
ns - 592
61-163
10-282
53C
2,3,6-trichlorophenol (4c)*
30
58-137
56 -180
51-153
531
2 4,5-trichlorophenol (4c)*
30
58-137
56-180
51-153
321
2,4,6-trichlorophenol
57
59 - 205
81-123
48 - 244
221
2,4,6-trichlorophenol-d2
47
43-183
21 - 363
69 -144
34 - 226
(1) Reference numbers beginning with 0 1 or 5 indicate a polutant quantified by the internal standard method, reference numbers beginning with 2 or 6
indicate a labeled compound quantified by the internal standard method, reference numbers beginning with 3 or 7 indicate a pollutant quantified by
isotope dilution
* measured by internal standard specification derived from related compound
ns - no specification limit is outside the range that can be measured reliably 1
-------
8 2 3) If these compounds now pass, system perfor-
mance is acceptable for all compounds and analysis
of blanks and samples may begin If, however, any of
the same compounds fail again, the analysis system
is not performing properly for the compounds In this
event, correct the problem and repeat the entire test
(section 8 21)
8 3 The laboratory shall spike all samples with labeled
compounds to assess method performance on the
sample matrix
8 3 1 Analyze each sample according to the method
beginning in section 10
8 3 2 Compute the percent recovery (P) of the labeled
compounds using the internal standard method (sec-
tion 7 5)
8 3 3 Compare the labeled compound recovery for each
compound with the corresponding limits in table 8 If
the recovery of any compound falls outside its warn-
ing limit, method performance is unacceptable for
that compound in that sample Therefore, the sample
matrix is complex and is to be diluted and reanalyzed
per section 15 4
8 4 As part of the OA program for the laboratory, method
accuracy for wastewater samples shall be assessed
and records shall be maintained After the analysis of
five wastewater samples for which the labeled com-
pounds pass the tests in section 8 3, compute the
average percent recovery (P) and the standard devia-
tion of the percent recovery (sp) for the labeled com-
pounds only Express the accuracy assessment as a
percent recovery interval from P - 2sp to P + 2sp
For example, if P = 90% and sp = 10%, the ac-
curacy interval is expressed as 70-110% Update the
accuracy assessment for each compound on a
regular basis (e g after each 5-10 new accuracy
measurements)
8 5 Blanks—reagent water blanks are analyzed to
demonstrate freedom from contamination
8 5 1 Extract and concentrate a blank with each sample lot
(samples started through the extraction process on
the same 8 hr shift, to a maximum of 20 samples)
Analyze the blank immediately after analysis of the
precision and recovery standard (section 614) to
demonstrate freedom from contamination
8 5 2 If any of the compounds of interest (tables 1 and 2) or
any potentially interfering compound is found in a
blank at greater than 10 uglL (assuming a response
factor of 1 relative to the internal standard for com-
pounds not listed in tables 1 and 2), analysis of
samples is halted until the source of contamination is
eliminated and a blank shows no evidence of con-
tamination at this level
8 6 The specifications contained in this method can be
met if the apparatus used is calibrated properly, then
maintained in a calibrated state The standards used
for calibration (section 7), calibration verification
(section 12 5), and for initial (section 8 2) and on-
going (section 12 7) precision and recovery should
be identical, so that the most precise results will be
obtained The GC/MS instrument in particular will
provide the most reproducible results if dedicated to
the settings and conditions required for the analyses
of semivolatiles by this method
8 7 Depending on specific program requirements, field
replicates may be collected to determine the preci-
sion of the sampling technique, and spiked samples
may be required to determine the accuracy of the
analysis when internal or external standard methods
are used
9 SAMPLE COLLECTION, PRESERVATION, AND
HANDLING
9 1 Collect samples in glass containers following con-
ventional sampling practices (reference 7) Com-
posite samples are collected in refrigerated glass
containers (section 5 1 3) in accordance with the re-
quirements of the sampling program
9 2 Maintain samples at 0-4 °C from the time of collection
until extraction If residual chlorine is present, add 80
mg sodium thiosulfate per liter of water EPA
Methods 330 4 and 330 5 may be used to measure
residual chlorine (reference 8)
9 3 Begin sample extraction within seven days of collec-
tion, and analyze all extracts within 40 days of extrac-
tion
10 SAMPLE EXTRACTION AND CONCENTRATION
(See figure 4)
10 1 Labeled compound spiking—measure 1 00 + 0 01
liter of sample into a glass container For untreated
effluents, and samples which are expected to be dif-
ficult to extract and/or concentrate, measure an addi-
tional 10 0 ± 0 1 mL and dilute to a final volume of
1 00 ± 0 1 liter with reagent water in a glass con-
tainer
10 11 For each sample or sample lot (to a maximum of 20)
to be extracted at the same time, place three 1 00 ±
0 01 liter aliquots of reagent water in glass con-
tainers
10 12 Spike 0 5 mL of the labeled compound spiking solu-
tion (section 6 8) into all samples and one reagent
water aliquot
10 13 Spike 1 0 mL of the precision and recovery standard
(section 6 14) into the two remaining reagent water
aliquots
10 14 Stir and equilibrate all solutions for 1-2 hr
10 2 Base/neutral extraction—place 100-150 mL
methylene chloride in each continuous extractor and
200-300 mL in each distilling flask
10 2 1 Pour the sample(s), blank, and standard aliquots into
the extractors Rinse the glass containers with
50-100 mL methylene chloride and add to the
respective extractor
10 2 2 Adjust the pH of the waters in the extractors to 12-13
with 6N NaOH while monitoring with a pH meter
Begin the extraction by heating the flask until the
methylene chloride is boiling When properly ad-
justed, 1-2 drops of methylene chloride per second
will fall from the condenser tip into the water After
1-2 hours of extraction, test the pH and readjust to
12-13 if required Extract (or 18-24 hours
10 2 3 Remove the distilling flask, estimate and record the
14
-------
STANDARD
[10.1.11
[10.1.2]
110.1.3]
[10.1.4]
[10.2|
[10.31
[10.4 2]
[10.4,10.51
[11.31
[11-41
1 L REAGENT
WATER
SPIKE
1 0 mL
OF STANDARDS
STIR AND
EQUILIBRATE
STANDARD OR BLANK
EXTRACT BASE/
NEUTRAL
ORGANIC
AQUEOUS
CONCENTRATE
TO 1 0 mL
ADD INTERNAL
STANDARD
INJECT
BLANK
1 L REAGENT
WATER
SAMPLE
STIR AND
EQUILIBRATE
J,
EXTRACT ACID
N
f
N
CONCENTRATE
CONCENTRATE
TO 2-4 mL
TO 2-4 mL
N
SPIKE
OF 200
ISOT
500 pL
pg/mL
3PES
1 L ALIQUOT
>
f
SPIKE
OF 200
ISOT
500 pL
pg/mL
DPES
STIR AND
EQUILIBRATE
EXTRACT BASE/
NEUTRAL
ORGANIC T AQUEOUS
^
EXTRACT ACID
CONCENTRATE
TO 1 0 mL
CONCE
TO 1
SITRATE
0 mL
V
f
>
f
ADD INTERNAL
STANDARD
ADD INTERNAL
STANDARD
N
>
f
INJECT
INJECT
FIGURE 4 Flow Chart for Extraction/Concentration of Precision and Recovery Standard, Blank, and Sample by
Method 1625. Numbers in Brackets [ ] Refer to Section Numbers in the Method
15
-------
volume of extract (to the nearest 100 mL), and pour 11
the contents through a drying column containing 7 to 1 -| -|
10 cm anhydrous sodium sulfate Rinse the distilling
flask with 30-50 mL of methylene chloride and pour
through the drying column Collect the solution in a
500 mL K-D evaporator flask equipped with a 10 mL
concentrator tube Seal, label as the base/neutral 11 2
fraction, and concentrate per sections 10 4 to 10 5
10 3 Acid extraction—adjust the pH of the waters in the
extractors to 2 or less using 6N sulfuric acid Charge
clean distilling flasks with 300-400 mL of methylene .. 3
chloride Test and adjust the pH of the waters after
the first 1-2 hr of extraction Extract for 18-24 hours
10 3 1 Repeat section 10 2 3, except label as the acid frac-
tion
10 4 Concentration—concentrate the extracts in separate 11 4
500 mL K-D flasks equipped with 10 mL concentrator
tubes
10 4 1 Add 1 to 2 clean boiling chips to the flask and attach
a three-ball macro Snyder column Prewet the col-
umn by adding approximately one mL of methylene
chloride through the top Place the K-D apparatus in a
hot water bath so that the entire lower rounded sur-
face of the flask is bathed with steam Adjust the ver-
tical position of the apparatus and the water
temperature as required to complete the concentra-
tion in 15 to 20 minutes At the proper rate of distilla- 12
tion, the balls of the column will actively chatter but j 2 1
the chambers will not flood When the liquid has
reached an apparent volume of 1 mL, remove the
K-D apparatus from the bath and allow the solvent to
drain and cool for at least 10 minutes Remove the
Snyder column and rinse the flask and its lower joint
into the concentrator tube with 1-2 mL of methylene
chloride A 5-mL syringe is recommended for this
operation
10 4 2 For performance standards (section 8 2 and 12 7)
and for blanks (section 8 5), combine the acid and
base/neutral extracts for each at this point Do not 12 2
combine the acid and base/neutral extracts for
samples
10 5 Add a clean boiling chip and attach a two ball micro
Snyder column to the concentrator tube Prewet the
column by adding approx 0 5 mL methylene chloride 12 3
through the top Place the apparatus in the hot water
bath Adjust the vertical position and the water
temperature as required to complete the concentra-
tion in 5-10 minutes At the proper rate of distillation,
the balls of the column will actively chatter but the 124
chambers will not flood When the liquid reaches an
apparent volume of approx 0 5 mL, remove the ap-
paratus from the water bath and allow to drain and
cool for at least 10 minutes Remove the micro 125
Snyder column and rinse its lower joint into the con-
centrator tube with approx 0 2 mL of methylene
chloride Adjust the final volume to 1 0 mL
10 6 Transfer the concentrated extract to a clean screw-
cap vial Seal the vial with a Teflon-lined lid, and mark
the level on the vial Label with the sample number
and fraction, and store in the dark at - 20 to - 10°C
until ready for analysis
GC/MS ANALYSIS
Establish the operating conditions given in tables 3 or
4 for analysis of the base/neutral or acid extracts,
respectively For analysis of combined extracts (sec-
tion 10 4 2), use the operating conditions in table 3
Bring the concentrated extract (section 10 6) or stan-
dard (sections 6 13-6 14) to room temperature and
verify that any precipitate has redissolved Verify the
level on the extract (sections 6 6 and 10 6) and bring
to the mark with solvent if required
Add the internal standard solution (section 6 10) to
the extract (use 1 0 nL of solution per 0 1 mL of
extract) immediately prior to injection to minimize the
possibility of loss by evaporation, adsorption, or
reaction Mix thoroughly
Inject a volume of the standard solution or extract
such that 100 ng of the internal standard will be in-
jected, using on-column or splitless injection For 1
mL extracts, this volume will be 1 0 nl Start the GC
column initial isothermal hold upon injection Start
MS data collection after the solvent peak elutes Stop
data collection after the benzo (ghi) perylene or pen-
tachlorophenol peak elutes for the base/neutral or
acid fraction, respectively Return the column to the
initial temperature for analysis of the next sample
SYSTEM AND LABORATORY PERFORMANCE
At the beginning of each 8 hr shift during which
analyses are performed, GC/MS system perfor-
mance and calibration are verified for all pollutants
and labeled compounds For these tests, analysis of
the 100 /ig/mL calibration standard (section 6 13)
shall be used to verify all performance criteria Ad-
justment and/or recalibration (per section 7) shall be
performed until all performance criteria are met Only
after all performance criteria are met may samples,
blanks, and precision and recovery standards be
analyzed
DFTPP spectrum validity—inject 1 fit of the DFTPP
solution (section 6 11) either separately or within a
few seconds of injection of the standard (section
12 1) analyzed at the beginning of each shift The
criteria in table 5 shall be met
Retention times—the absolute retention time of
2,2 -difluorobiphenyl shall be within the range of
1078 to 1248 seconds and the relative retention
times of all pollutants and labeled compounds shall
fall within the limits given in tables 3 and 4
GC resolution—the valley height between an-
thracene and phenanthrene at m/z 178 (or the
analogs at m/z 188) shall not exceed 10 percent of
the taller of the two peaks
Calibration verification—compute the concentration
of each pollutant (tables 1 and 2) by isotope dilution
(section 7 4) for those compounds which have la-
beled analogs Compute the concentration of each
pollutant which has no labeled analog by the internal
standard method (section 7 5) Compute the concen-
tration of the labeled compounds by the internal stan-
dard method These concentrations are computed
based on the calibration data determined in section 7
16
-------
12 5 1 For each pollutant and labeled compound being
tested, compare the concentration with the calibra-
tion verification limit in table 8 If all compounds meet
the acceptance criteria, calibration has been verified
and analysis of blanks, samples, and precision and
recovery standards may proceed If, however, any
compound fails, the measurement system is not per-
forming properly for that compound In this event,
prepare a fresh calibration standard or correct the
problem causing the failure and repeat the test (sec-
tion 12 1), or recalibrate (section 7)
12 6 Multiple peaks—each compound injected shall give
a single, distinct GC peak
12 7 On-going precision and accuracy
12 7 1 Analyze the extract of one of the pair of precision and
recovery standards (section 1 o 1 3) prior to analysis
of samples from the same lot
12 7 2 Compute the concentration of each pollutant (tables
1 and 2) by isotope dilution (section 7 4) for those
compounds which have labeled analogs Compute
the concentration of each pollutant which has no
labeled analog by the internal standard method (sec-
tion 7 5) Compute the concentration of the labeled
compounds by the internal standard method
12 7 3 For each pollutant and labeled compound, compare
the concentration with the limits for on-going ac-
curacy in table 8 If all compounds meet the accep-
tance criteria, system performance is acceptable and
analysis of blanks and samples may proceed If,
however, any individual concentration falls outside of
the range given, system performance is unaccep-
table for that compound NOTE The large number of
compounds in table 8 present a substantial probabil-
ity that one or more will fail when all compounds are
analyzed To determine if the extraction/concentra-
tion system is out of control or if the failure is caused
by probability, proceed as follows
12 7 3 1 Analyze a second aliquot of the pair of precision and
recovery standards (section 1013)
12 7 3 2 Compute the concentration for only those pollutants
or labeled compounds that failed the previous test
(section 12 7 3) If these compounds now pass, the
extraction/concentration processes are in control
and analyses of blanks and samples may proceed If,
however, any of the same compounds fail again, the
extraction/concentration processes are not being
performed properly for these compounds In this
event, correct the problem, re-extract the sample lot
(section 10) and repeat the on-going precision and
recovery test (section 12 7)
12 7 4 Add results which pass the specifications in 12 7 3 to
initial and previous on-going data Update QC charts
to form a graphic representation of continued
laboratory performance (figure 5) Develop a state-
ment of laboratory accuracy for each pollutant and
labeled compound by calculating the average per-
cent recovery (R) and the standard deviation of per-
cent recovery (sr) Express the accuracy as a
recovery interval from R - 2sr to R + 2sr For exam-
ple, if R = 95% and sr = 5%, the accuracy is
85-105%
5
*
55
o
ui
is
H
lu %
u]
£ z
45,000
35.000
25,000
_1_
_l l_
ANTHRACENE D„
• + 3*>
-35
3 4 5 6 7 8 9
ANALYSIS NUMBER
1 00
> i
UJ <
H
Z
<
ANTHRACENE
. — - #
0 90 i j 1 1 1 1 1 i r~
6/1 6/1 6/1 6/1 6/2 6/2 6/3 6/3 6/4 6/5
DATE ANALYZED
• + 3'>
-3s
FIGURE 5 Quality Control Charts Showing Area
(top graph) and Relative Response of
Anthracene to Anthracene-d10 (lower graph)
Plotted as a Function of Time or Analysis
Number
13 QUALITATIVE DETERMINATION
13 1 Qualitative determination is accomplished by com-
parison of data from analysis of a sample or blank
with data from analysis of the shift standard (section
12 1) and with data stored in the spectral libraries
(section 7 2 4) Identification is confirmed when
spectra and retention times agree per the criteria
below
13 2 Labeled compounds and pollutants having no la-
beled analog
13 2 1 The signals for all characteristic masses stored in the
spectral library (section 7 2 4) shall be present and
shall maximize within the same two consecutive
scans
13 2 2 Either (1) the backgound corrected EICP areas, or (2)
the corrected relative intensities of the mass spectral
peaks at the GC peak maximum shall agree within a
factor of two (0 5 to 2 times) for all masses stored in
the library
13 2 3 The retention time relative to the nearest eluted inter-
nal standard shall be within ± 15 scans or ± 15
seconds, whichever is greater of this difference in the
shift standard (section 12 1)
13 3 Pollutants having a labeled analog
13 31 The signals for all characteristic masses stored in the
spectral library (section 7 2 4) shall be present and
shall maximize within the same two consecutive
scans
13 3 2 Either (1) the backgound corrected EICP areas, or (2)
the corrected relative intensities of the mass spectral
peaks at the GC peak maximum shall agree within a
factor of two for all masses stored in the spectral
library
13 3 3 The retention time difference between the pollutant
and its labeled analog shall agree within ± 6 scans
or ± 6 seconds (whichever is greater) of this dif-
ference in the shift standard (section 12 1)
17
-------
13 4 Masses present in the experimental mass spectrum
that are not present in the reference mass spectrum
shall be accounted for by contaminant or backgound
ions If the experimental mass spectrum is con-
taminated, an experienced spectrometrist (section
1 4) is to determine the presence or absence of the
compound
14 QUANTITATIVE DETERMINATION
14 1 Istope dilution—by adding a known amount of a
labeled compound to every sample prior to extrac-
tion, correction for recovery of the pollutant can be
made because the pollutant and its labeled analog
exhibit the same effects upon extraction, concentra-
tion, and gas chromatography Relative response
(RR) values for sample mixtures are used in conjunc-
tion with calibration curves described in section 7 4
to determine concentrations directly, so long as
labeled compound spiking levels are constant For
the phenol example given in figure 1 (section 7 4 1),
RR would be equal to 1 114 For this RR value, the
phenol calibration curve given in figure 1 indicates a
concentration of 27 /*g/ml_ in the sample extract
(^ex)
14 2 Internal standard—compute the concentration in the
extract using the response factor determined from
calibration data (section 7 5) and the following equa-
tion
Cex (^g/mL) = (As X C|s)
(AIS x RF)
where Cex is the concentration of the compound in
the extract, and the other terms are as defined in sec-
tion 7 5 1
143
14 4
14 5
The concentration of the pollutant in water is com-
puted using the volumes of the original water sample
(section 10 1) and the final extract volume (section
10 5), as follows
_ (Cex x Vex)
Concentration in water (hqIL)
Vs
where Vex is the extract volume in mL, and Vs is the
sample volume in liters
If the EICP area at the quantitation mass for any com-
pound exceeds the calibration range of the system,
the extract of the dilute aliquot (section 101) is
analyzed by isotope dilution, otherwise, the extract is
diluted by a factor of 10, 9 ftL of internal standard
solution (section 6 10) are added to a 1 0 mL aliquot,
and this diluted extract is analyzed by the internal
standard method (section 14 2) Quantify each com-
pound at the highest concentration level within the
calibration range
Report results for all pollutants and labeled com-
pounds (tables 1 and 2) found in all standards,
blanks, and samples, in figlL, to three significant
figures Results for samples which have been diluted
are reported at the least dilute level at which the area
at the quantitation mass is within the calibration
range (section 14 4) and the labeled compound
recovery is within the normal range for the method
(section 15 4)
15 ANALYSIS OF COMPLEX SAMPLES
15 1 Untreated effluents and other samples frequently
contain high levels (>1000 ftgll) of the compounds
of interest, interfering compounds, and/or polymeric
materials Some samples will not concentrate to one
mL (section 10 5), others will overload the GC col-
umn and/or mass spectrometer
15 2 Analyze the dilute aliquot (section 10 1) when the
sample will not concentrate to 1 0 mL If a dilute ali-
quot was not extracted, and the sample holding time
(section 9 3) has not been exceeded, dilute an aliquot
of the sample with reagent water and re-extract (sec-
tion 10 1), otherwise, dilute the extract (section 14 4)
and analyze by the internal standard method (section
14 2)
15 3 Recovery of internal standard—the EICP area of the
internal standard should be within a factor of two of
the area in the shift standard (section 12 1) If the ab-
solute areas of the labeled compounds are within a
factor of two of the respective areas in the shift stan-
dard, and the internal standard area is less than one-
half of its respective area, then internal standard loss
in the extract has occurred In this case, use one of
the labeled compounds (preferably a polynuclear
aromatic hydrocarbon) to compute the concentration
of a pollutant with no labeled analog
15 4 Recovery of labeled compounds—in most samples,
labeled compound recoveries will be similar to those
from reagent water (section 12 7) If the labeled com-
pound recovery is outside the limits given in table 8,
the dilute extract (section 10 1) is analyzed as in sec-
tion 14 4 If the recoveries of all labeled compounds
and the internal standard are low (per the criteria
above), then a loss in instrument sensitivity is the
most likely cause In this case, the 100/
-------
RIC DATA: ABNID1166 #1
03/13/84 5:24:00 CALI: ABN1D1166 ttl
SAMPLE: AB,G,VER,00100,00,C,NA:NA,NA$
CONDS.: 1625fl,30l1,0.25m, 5@30,30-28868,15B280,30CIVSI
RANGE: G 1,3200 LABEL: N 2, 3.0 QUAN: A 2, 2.0 J
SCANS 1 TO 3200
0 BASE: U 20, 3
100.0'
JJ
J
I
715776.
1080
15:50
1500
23:45
r
2888
31:40
2500
39:35
i
3800
47:30
SCAN
TIPIE
FIGURE 6 Chromatogram of Combined Acid/Base/Neutral Standard.
17 REFERENCES
1 "Performance Tests for the Evaluation of Com-
puterized Gas Chromatography/Mass Spectrometry
Equipment and Laboratories," USEPA, EMSL/Cincin-
nati, OH 45268, EPA-600/4-80-025 (April 1980)
2 "Working with Carcinogens," DHEW, PHS, CDC,
NIOSH, Publication 77-206, (Aug 1977)
3 "OSHA Safety and Health Standards, General In-
dustry," OSHA 2206, 29 CFR 1910 (Jan 1976)
4 "Safety in Academic Chemistry Laboratories," ACS
Committee on Chemical Safety (1979)
5 "Inter-laboratory Validation of US Environmental
P'otection Agency Method 1625," USEPA, Effluent
Guidelines Division, Washington, DC 20460 (June
15, 1984)
6 "Handbook of Analytical Quality Control in Water
and Wastewater Laboratories," USEPA, EMSL/Cin-
cinnati, OH 45268, EPA-600/4-79-019 (March 1979)
7 "Standard Practice for Sampling Water," ASTM
Annual Book of Standards, ASTM, Philadelphia, PA,
76 (1980)
8 "Methods 330 4 and 330 5 for Total Residual
Chlorine," USEPA, EMSL/Cincinnati, OH 45268,
EPA 600/4-70-020 (March 1979)
9 Colby, B N, Beimer, R G , Rushneck, D R , and
Telliard, W A, "Isotope Dilution Gas Chromatog-
raphy-Mass Spectrometry for the Determination of
Priority Pollutants in Industrial Effluents," USEPA, Ef-
fluent Guidelines Division, Washington, DC 20460
(1980)
19
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