United States
Environmental Protection
Agency
Environmental Monitoring and
Support Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S4-85/010 Mar 1985
4>EPA Project Summary
Single Laboratory Validation of
EPA Method 8030—Acrolein,
Acrylonitrile, and Acetonitrile
Samuel V. Lucas, Thomas F. Cole, Alice Riggin, and W. Marcus Cooke
EPA Method 8030 was modified and
evaluated with revised chromatographic
conditions for the de'termination of
acrolein, acrylonitrile, and acetonitrile
in groundwater, solid, and organic liquid
matrices. Method validation studies
were conducted on each of the four
sample preparation techniques included
in Method 8030, namely (1) heated
purge-and-trap (HP&T); (2) polyethyl-
ene glycol (PEG) extraction followed by
HP&T; (3) direct liquid injection (DLI);
and (4) manual heated headspace
(HHS). Each method validation involved
the determination of the method detec-
tion limit (MDL) and seven replicate
analyses of one or two matrices, each
analyzed unspiked and spiked at two
concentration levels. Groundwater was
analyzed by the HP&T method; a solid
waste was analyzed by the PEG/HP&T
technique and by the HHS method; and
a liquid organic waste was analyzed by
DLI and by HHS methods.
The HP&T method gave good recovery
(85 to 96 percent) and precision for the
three method analytes in groundwater.
The PEG/HP&T method gave good
recovery (76 to 96 percent) for aceto-
nitrile and acrylonitrile in the solid waste
but poor recovery for acrolein (10
percent), which apparently decomposed
in that matrix. Problems encountered
with the carryover of PEG indicated
that additional modifications of this
method are needed. The DLI technique
gave good results for the determination
of all three analytes (86 to 111 percent
recovery) in the organic liquid waste;
however, late eluting material may
present serious problems in some cases.
The HHS method gave distinctly less
accurate and less precise results than
the PEG/purge-and-trap method for the
determination of acetonitrile and acryl-
onitrile in the solid waste sample.
Acrolein was not recovered at all by the
method due, apparently, to decomposi-
tion during the one-hour equilibration
at 90°C. The HHS method gave ex-
tremely erratic results for the analysis of
the organic liquid waste and was, there-
fore, considered completely unsatisfac-
tory for such samples.
This Project Summary was developed
by EPA's Environmental Monitoring and
Support Laboratory, Cincinnati, OH, to
announce key findings of the research
project that is fully documented in a
separate report of the same title (see
Project Report ordering information at
back).
Introduction
The objective of this program was to
perform single-laboratory validation of
U.S. EPA Method 8030, which covers the
gas chromatographic (GC) determination
of acrolein, acrylonitrile, and acetonitrile
in groundwater, liquid wastes, and solid
wastes.
Method 8030 provides four sample
preparation options: (1) heated purge-
and-trap(HP&T) using EPA Method 5030;
(2) polyethylene glycol extraction followed
by HP&T (PEG/HP&T) using EPA Method
5030; (3) DLI onto the GC column (DLI);
and (4) heated headspace sampling (HHS)
using EPA Method 5020.
This method validation study was
undertaken in response to a variety of
prior experience which suggested that
Method 603, on which Method 8030 is
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/'"
based, was not a reliable method. A
previous single laboratory method vali-
dation study performed for EPA produced
no useful data. In addition, several inves-
tigators have queried EPA regarding
difficulties with the reproducibility of the
gas chromatography and problems en-
countered from acetone interference.
Thus, development and use of improved
chromatographic conditions was a critical
first step in this work.
Analytical Methods Evaluation
Gas Chromatography (GC)
Investigations were conducted to iden-
tify a GC column which would effectively
provide analysis capability for the three
method analytes. Both of the columns
specified in the 1982 revision of EPA
Method 603, on which EPA Method 8030
is based, were found to be unacceptable.
Durapak CW400/Porasil C resulted in
coelution of acetone and acrolein and
such severe peak tailing that low level
injections (—100 ng) did not provide
usable data. Chromosorb 101 resulted in
exact coelution of acrolein and acetoni-
trile and partial resolution of acetone
from acrylomtrile; but otherwise, this
column performs adequately for acrolein
and acrylonitrile in the absence of aceto-
nitrile. Other column packings were tried
and the following results were obtained:
1 percent SP-1000/Carbopack B gave
moderate tailing and acrolein-acetone
coelution; 0.2 percent CW 1500/Carbo-
pack C resulted in inadequate retention
and severe peak tailing; and Chromosorb
104 provided high temperature of elution,
unacceptable isothermal elution time for
acetonitnle and moderate tailing. The
Porapak QS column packing used in this
work was the only one tested which
provided baseline separation between the
method analytes as well as two potential
interferences of interest to EPA: acetone,
which elutes between acrolein and acryl-
onitrile; and methylene chloride, which
elutes between methanol and acetoni-
trile. This packing also provided good GC
peak shape at low concentrations.
Purge-and-Trap Conditions
In the initial work on this program,
some experiments were performed to
compare method performance using the
trap desorption conditions recommended
by EPA Method 5030 with modified
conditions recommended by EPA's Envi-
ronmental Monitoring and Support Labo-
ratory in Cincinnati, OH (EMSL). Stand-
ards containing 30 A»g/L of each analyte
were analyzed in triplicate using the
desorption conditions specified by EPA
Method 5030 and those recommended by
EMSL. The modified desorption condi-
tions, 180°C for 1.5 mm, used in the
validation analyses resulted in recoveries
reduced 4 to 8 percent compared to those
obtained with the EPA Method 5030
conditions of 100°C for 2 0 mm. However,
significantly better relative standard de-
viation (RSD) values of 1.1, 1.2, and 1.2
percentforthe 180°C/1 5 min conditions
were obtained compared to 9.3, 8.0, and
1.8 percent for the 100°C/2.0 mm condi-
tions for acetonitrile, acrolein, and acryl-
onitrile, respectively. In summary, the
180°C/1.5 mm desorption conditions
gave improved peak heights for aceto-
nitrile and acrolein resulting in better
reproducibility, which is probably due to
the more rapid delivery of trapped analytes
to the GC column. The small difference in
recovery may not be significant since
these values are less than the observed
standard deviations for the 100°C/2.0
min conditions The leap bake temperature
of 210°C was employed since it is gener-
ally desirable that the trap bake tempera-
ture be higher than the desorption
temperature. The low (100°C) desorption
temperature specified in EPA Method
5030 was required by the initial GC
column temperature of 45°C and the
sensitivity of the primary column (Durapak
CW400/Porasil C) to the presence of
liquid water on the column which would
be introduced by rapid trap heating to
180°C While the Porapak QS column
packing is generally not susceptible to
problems caused by liquid water, this
potential problem is avoided since the
initial column temperature (110°C) pre-
vents condensation of water vapor
Linear Dynamic
Range of the Detector
The linear dynamic range (LDR) of the
gas chromatographic system was evalu-
ated for acetonitrile, acrolein and acrylo-
nitrile using septum GC injections of
aqueous calibration standards ranging in
concentration from 0.5 to 500 (jg/mL.
The regression line analysis results
showed excellent linearity of the GC
system and FID detector over the three
orders of magnitude range tested for the
three method analytes.
Method Validation
Method validation was conducted for
EPA Method 5030 using four different
sample introduction techniques: (1) EPA
Method 5030, a heated purge-and-trap
method (HP&T) was evaluated with an
85°C purge for aqueous samples; (2) a
HP&T method with a polyethylene glycol
(PEG) extraction for solid samples; (3) a
direct liquid injection (DLI) procedure for
the analysis of liquid wastes; and (4) EPA
Method 5020, a heated headspace
method (HHS) for direct injection of an
aliquot of headspace of a sample equili-
brated at 90°C. A validation data set for a
particular technique consisted of a de-
termination of the background levels of
analyte m the matrix and analysis of
samples spiked at two levels with seven
replicates at each level. Table 1 indicates
the scope of this method validation study
by showing the seven replicate data sets
which were produced. The results of the
MDL determinations and the individual
validation experiments for groundwater,
a solid sediment waste sample, and a
liquid waste sample using HP&T, PEG/
HP&T, DLI, and HHS at both low and high
spiking levels are summarized in Table 2.
These results are discussed individually
below by sample matrix type and analysis
technique.
HP&T Groundwater
Analysis Results
Groundwater was obtained from the
well of a Battelle staff member who lives
in rural Union County, Ohio. The well
depth was approximately 30 ft, and the
raw groundwater was broadly classified
as very hard with high levels of carbonate
and iron. The RSD's for all compounds
spiked at the low level of 5 to 10 fjg/L in
the groundwater were less than six
percent with average recoveries ranging
from 90 to 95 percent. As for nearly all
sample sets analyzed, the RSD's for
acetonitrile are significantly higher than
those for acrolein and acrylonitrile. The
reason for the lower precision for aceto-
nitrile in all determinations appears to be
due to the relatively low purging efficiency
of this compound, estimated to be 40 to
50 percent. The RSD's for all compounds
spiked at the high level of 75 to 150 Aig/L
in groundwater were less than seven
percent with average recoveries ranging
from 85 to 91 percent.
PEG/HP& T Sediment
Analysis Results
Sediment from a waste stream settling
basin at a chemical plant producing two
of the three method parameters was
provided to Battelle by the chemical plant
personnel. The results for low level sedi-
ment spikes ranging from 5 to 15 mg/kg
indicated that acrolein apparently decom-
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posed in the solid waste sample after
storage overnight at 4°C and the average
recovery for this compound was only 10
percent. Average recoveries for acetoni-
trile spiked at 15 mg/kg and acrylonitrile
spiked at 5 mg/kg were 97 and 76
percent, respectively, with RSD's of less
than 10 percent m both cases. As deter-
mined for the low-level spike samples,
acrolein was lost due to apparent decom-
position in the high-level spike samples
also, while the average recoveries for
acetonitrile and acrylonitrile, both spiked
at the 100 mg/kg level, were 96 and 84
percent, respectively.
DLI Liquid Organic
Waste Results
The nonaqueous liquid organic waste
used in this validation was a black, ink-
like, low-viscosity mixture of chlorinated
hydrocarbons with a density of 1.25
gm/mL. The principal constituents pre-
viously identified by EPA Method 624
were dichloroethane, trichloroethane,
and tetrachloroethane isomers. Numer-
ous other halogenated C2- and Ci-
compounds were also present.
Recoveries for the low-level spike liquid
waste ranged from 86 percent for aceto-
7able 1. Scope of the Method Validation Experiments Performed
Method
(Matrix)
5030, HP&T
(groundwater)
5030, PEG /HP&T
(solid waste)
DLI
(liquid waste)
5020, HHS
(liquid waste)
(solid waste)
{
MDL™
(c)
X
X
X
Seven Replicate u
Nonspike
(d)
Id)
X
X
X
ata Set Obtained (>
Low Spike™
X
X .
X
X
X
0
High Spike""
X
X
X
X
X
'"'The matrix for method dete ction limit (MDL) was reagent water for a II but DLI for which the matrix
was toluene.
M Low spike levels were chosen to be at or near the MDL level when possible, high spike levels were
generally 10-fold higher.
(^The groundwater low spike data were used to compute MDL.
MtThree to six replicates of unspiked samples were analyzed with both the low and high spike data
sets; no separate sevep replicate experiment was performed.
nitrile to 111 percent for acrylonitrile for
2.5 to 12 mg/L spike levels and all relative
standard deviations were less than 4
percent. For the high-level spike liquid
waste samples at the 125 mg/L spike
level, recoveries ranged from 98 percent
for acrylonitrile to 109 percent for aceto-
nitrile, with relative standard deviations
of 11 to 12 percent in all cases.
HHS Sediment Analysis Results
The sediment sample used in the PEG/
HP&T validation was also used for the
HHS method validation work using EPA
Method 5020. As described above for the
PEG/HP&T analyses, acrolein was not
stable in this matrix, and no analysis
results were tabulated for this analyte.
Results for the low-level spike samples
yielded percent recoveries and percent
RSD's of 46 ±48 and 51 ±32 for the 10
and 100 mg/kg levels of acetonitrile and
acrylonitrile, respectively. The corre-
sponding values for the high-level spike
samples were 120 ± 65 and 76 ± 20, for
the 100 and 500 mg/kg levels of aceto-
nitrile and acrylonitrile, respectively. The
high percent RSD values (20 to 80
percent) observed for the solid waste data
sets can be attributed to variability in the
manual headspace sampling and injection
procedure. When sampling headspace in
equilibrium at 90°C with a wet sample, a
significant but variable amount of liquid,
estimated to be 50 to 200 ^L, condenses
in the 5-mL sampling syringe which is at
room temperature. Upon injection of the
sample, a variable amount of this con-
densate, which is enriched in the spiked
analytes, is delivered to the GC column.
Table 2. Summary of Method Validation Results
Acetonitrile
Acrolein
Acrylonitrile
(Matrix)
MDL'
Percent Recovery
± Percent RSD{a
Low Spike High Spike MDL"
Percent Recovery
± Percent RSD(C]
Low Spike High Spike MDL"
Percent Recovery
± Percent RSD""
Low Spike High Spike
5030, HP&T 3 ug/L 0.7 fjg/L 0.5 fjg/L
(groundwater) 95 ±5 92 ±6 90 ±2 95 ±6
5030, PEG/HP&T 1 mg/kg™ 0.7 mg/kg"" 03 mg/kg""
(solid waste) 98 ±10 95 ±13 10 ±8 8 + 7
DLI 0.8 mg/L 0.6 mg/L 0 5 mg/L
(liquid waste) 86 ±2 109 ±11 94 ±3 101 ±12
5020, HHS 1 mg/kg 0.3 mg/kg 0.4 mg/kg
(solid waste) 46 ±48 120 ±65 (e) (e)
(liquid waste) -20 ±1900 700 ±100 (e) (e)
*]HP& T: heat purge-and-trap; PEG: polyethylene glycol; DLI: direct liquid injection; HHS: heated headspace sampling.
94 ±2
76 ±5
111 ±2
32 ±51
70 ±21 00
86+2
83+6
98 + 12
76 ±20
250 ±1300
bl * Matrices: HP&T, buffered reagent water and groundwater; PEG/HP&T, reagent PEG; DLI, toluene; HHS. buffered reagent water.
C'/?5D = Relative Standard Deviation
"'Assuming a 1 -gm sample extracted with 40 mL PEG and a 200-uL PEG extract aliquot analyzed
e> Acrolein was not stable under HHS conditions.
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HHS Organic Liquid
Analysis Results
The organic liquid used in the evalu-
ation of the DLI method was also used in
the validation of the HHS method.
Results for the low-level spike liquid
organic waste samples yielded percent
recoveries and percent RSD's of -20 +
1900 and 40 ±2100 for the 10 and 100
mg/kg level of acetonitrile and acryloni-
trile, respectively. The corresponding
values for the high level spike are 700 ±
110 and 250 ± 1300, respectively, as
before. The extremely poor accuracy and
reproducibility observed for these sam-
ples is due to the problem of sample
condensation in the 5-mL syringe during
headspace sampling which was described
above for the solid waste samples. In all
cases except the unspiked sample set, the
two-standard-deviation confidence inter-
val for the average amount found extends
to negative values. The large degree of
irreproducibility encountered for this
matrix using the heated headspace
approach does not allow even an order-
of-magnitude confidence interval in a
single replicate analysis protocol.
Comparison of MDLs and
Validation Results
The PEG/HP&T, DLI, and HHS methods
all have approximately the same MDL
values for their respective clean matrices
which were toluene for DLI and reagent
water for the PEG/HP&T and HHS. As
expected, the MDL values for direct HP&T
are about 1000-fold lower. Solid waste
was analyzed by both PEG/HP&T and
HHS, and the PEG/HP&T approach is
clearly superior in both accuracy and
precision for the solid waste used. The
liquid organic waste was analyzed by
both DLI and HHS, and the former method
is clearly the more acceptable one for the
matrix used. Poor recovery of acrolem for
the solid waste by PEG/HP&T compared
with that for groundwater using HP&T
suggests that acrolein was either irrevers-
ibly adsorbed or decomposed during the
4°C overnight equilibration with the solid
waste. In the case of the HHS method, the
data clearly indicate that decomposition
of acrolein during the 1-hr, 90°C equili-
bration isa major factor sincethe standard
addition of acrolein, added just prior to
the 90°C equilibration, is also nearly
quantitatively lost.
Conclusions
The validation results contained m this
report support the following conclusions
regarding the performance of Method
8030 and associated sample introduction
techniques for the determination of aceto-
nitrile, acrolein, and acrylonitrile in
groundwater, a solid waste, and an
organic liquid waste:
• The previously recommended GC
column (Chromosorb 101) is unsuit-
able for the sepaVation of acetonitrile
from acrolein and acrolein from ace-
tone, a common interference.
• The HP&T analysis option (Method
5030) works very well for the deter-
mination of low parts-per-billion levels
of the method analytes in groundwater.
• The PEG sample preparation methoi
for solids (Method 5030) provides gooi
precision and accuracy at the lov
parts-per-million level, but is subjec
to failure upon extended use due t
apparent aerosolization of PEG whicl
contaminates the purge-and-trap ap
paratus and leads to inconsisten
results.
• The PEG cleanup procedure fron
Method 5030 is not sufficient to pro
vide clean reagent to analyze thi
method analytes at low parts-per
million levels.
• Acrolein stability is not understooi
completely, and more work is neces
sary to develop sample preservatioi
criteria for this analyte particularly ii
solid matrices.
• The DLI sample introduction techniqui
is precise and accurate for the deter
mination of method parameters at lov
parts-per-million levels.
• The manual heated headspace pro
cedure does not provide acceptabli
results for analysis of the organic liquii
waste sample and provides such ;
high level of imprecision for solii
samples that it should be used only fo
approximation (i.e., a maximum of om
significant figure).
5. V. Lucas, T. F. Cole, A. Riggin, and W. M. Cooke are with Battelle-Columbus
Laboratories, Columbus, OH 43201.
James E. Longbottom is the EPA Project Officer (see below).
The complete report, entitled "Single Laboratory Validation of EPA Method
8030—A crolein, A crylonitrile. and A cetonitrile, "(Order No. PB85-165 82 7/A S;
Cost: $16.00, subject to change) will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Environmental Monitoring and Support Laboratory
U.S. Environmental Protection Agency
Cincinnati, OH 45268
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
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