United States
Environmental Protection
Agency
Environmental Monitoring and
Support Laboratory
Cincinnati OH 45268
Research and Development
EPA-600/S4-85-001 Feb. 1985
Project Summary
Evaluation of EPA Method 603
(Modified)
S. V. Lucas. T. F. Cole, A. Riggin, and W. M. Cooke
EPA Method 603 was modified and
evaluated with newly established chro-
matographic conditions for the deter-
mination of acrolein, acrylonitrile, and
acetonrtrile. The recommended chroma-
tographic column and conditions speci-
fied in the original method were found
to be unsuitable when acetonitrile was
included as a method parameter. Pora-
pak QS wa» found to perform well as a
gas chromatography (GC) packing for
the three method parameters, and
method validation using reagent water.
Publicly Owned Treatment Works
(POTW) outfall water, and industrial
wastewater was successfully perform-
ed. Recoveries and precisions were
determined at two spiking levels in each
of the three matrices. Seven replicates
were analyzed for each of the six spike-
level/matrix sets. For acetonitrile,
recoveries for the six sets ranged from
86 to 111 percent (average. 99 percent),
with precisions ranging from 3 to 17
percent relative standard deviation
(RSD), (average, 11 percent RSD). The
corresponding values for acrylonitrile
were recoveries ranging from 84 to 104
percent (average, 97 percent) and pre-
cisions ranging from 3 to 8 percent
RSD (average. 4 percent RSD). Acrolein
was unstable in the industrial waste-
water, even though the water was
buffered at pH 4.5 before spiking. For
the other two matrices, the acrolein
recovery ranged from 80 to 104 percent
(average, 94 percent) and the precisions
ranged from 1 to 4 percent RSD
(average, 3 percent RSD). The loss of
acrolein due to apparent chemical or
biological degradation in the industrial
wastewater underscores the current
lack of understanding of the chemical
factors that control the stability of
acrolein in aqueous systems. All of the
data sets were quantified using both an
internal standard method and an ex-
ternal standard method, and both
methods of quantification provided
essentially identical accuracy and pre-
cision results.
This report was submitted in partial
fulfillment of Contract Number 68-03-
1760, Work Assignment Number 5, by
Battelle's Columbus Laboratories. The
research reported here was conducted
under the sponsorship of the U.S.
Environmental Protection Agency.
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 Environmental Protection Agency's
(EPA's) Environmental Monitoring and
Support Laboratory (EMSL), Cincinnati,
Ohio, has primary responsibility for devel-
oping and evaluating monitoring methods
for organic pollutants in industrial waste-
waters. Method 603, developed by EPA,
for wastewater monitoring involves the
use of a heated purge-and-trap technique
and gas chromatographic (GC) analysis
for the determination of acrolein and
acrylonitrile.
This method validation study was
undertaken in response to the experience
of various laboratories which suggested
that Method 603 was not a reliable
analysis method. For example, a previous
single laboratory method validation study
performed for EPA by another contracting
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laboratory produced no useful data. In
addition, several investigators have quer-
ied EPA regarding difficulties with the
reproducibilityof thegaschromatography
and problems encountered from acetone
interference. Thus, development and use
of improved chromatographic conditions
was a critical first step in this work.
In an effort to increase the usefulness
and scope of Method 603, Battelle
Columbus Laboratories was contracted to
conduct research to: (1) recommend
modifications to Method 603 for improv-
ing the GC analysis; (2) evaluate the
feasibility of including acetonitrile as a
method parameter; and (3) validate the
method, as modified, using three matrices
(reagent water, POTW wastewater and a
relevant industrial wastewater) and two
spiking levels ([a "low" level near the
method detection limit [MDL] and a "high"
level at least 10-fold higher than the
"low" level]).
Analytical Method Evaluation
GC Column Evaluations
Since acetonitrile was to be included in
the parameter list of Method 603, the
identification of a suitable GC column for
the separation of all three compounds,
acetonitrile, acrolein, and acrylonitrile,
was a necessary first step. The separation
of methylene chloride and acetone from
the method parameters was also a con-
sideration in selecting the column to be
used for validation.
Both of the columns specified in the
1982 revision of Method 603 were de-
ter mined to be unacceptable. Chromosorb
101 resulted in exact coelution of acrolein
and acetonitrile and partial resolution of
acetone from acrylonitrile but otherwise
it performs adequately for acrolein and
acrylonitrile in the absence of acetonitrile.
Durapack 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. Other column packings were tried,
and the results obtained were as follows:
(1) 1 percent SP-1000/Carbopack B
(moderate tailing and acrolein-acetone
coelution); (2) 0.1 percent CW400/Car-
bopack C (inadequate retention and
severe peak tailing); and (3) Chromosorb
104 (high temperature of elution, unac-
ceptable isothermal elution time for
acetonitrile and moderate tailing). The
column packing used in this work (Porapak
QS) was the only one tested that provided
good GC peak shape at low levels and
baseline separation between the method
analytes as well as two potential inter-
ferences of interest to EPA (acetone,
which elutes between acrolein and acryl-
onitrile, and methylene chloride, which
elutes between methanol and acetoni-
trile).
Purge-and-Trap Conditions
The purge-and-trap conditions for this
validation effort included an 85°C purge
with helium at 20 mL/minute flow rate
for 15 minutes, a 1.5 minute desorption
at 180°C, and a 210°C trap bake for 10
minutes. These conditions were recom-
mended by EMSL staff, and were compared
to the original Method 603 conditions. In
summary, the conditions gave improved
peak heights for acetonitrile and acrolein
and better reproducibility, due, apparently,
to the more rapid delivery of trapped
analytes to the GC column and the
resulting production of narrower and
taller GC peaks. Actual recoveries, how-
ever, were about the same for the two
conditions. The trap bake temperature of
210°C was employed, since it is generally
desirable that the trap bake temperature
be higher than the desorption tempera-
ture. The low (100°C) desorption tem-
perature specified in the 1982 version of
Method 603 was required by the initial
GC column temperature of 45°C and the
sensitivity of Durapak CW400/Porasil C
to the presence of liquid water on the
column, which would be caused by rapid
trap heating to 180°C. For the Porapak
QS column packing, problems caused by
liquid water are of no concern, since the
initial column temperature is 110°C.
Moreover, macroreticular phases are
generally not susceptible to water dam-
age.
Method Validation
Validation consisted of the analysis of
seven replicates at two spiking levels for
each of three matrices: reagent water,
Columbus POTW secondary effluent, and
industrial wastewater from the outfall of
a manufacturing plant producing two of
the analytes. The water samples were
buffered before spiking at pH 4.5 ±0.2 by
the addition of sodium citrate to approxi-
mately 0.1 m/W and pH adjustment using
a glass electrode pH meter. Spiked
samples were allowed to equilibrate
overnight at ice temperature before
analysis on the following day.
A summary of the results for the method
validation using reagent water, Columbus
POTW effluent, and the industrial waste-
water are presented in Tables 1,2, and 3,
respectively. All quantifications were
performed using both external standard
calibration and internal standard (IS)
calibration with 1 -chloropropane, but only
the external standard results are pre-
sented in the tables. In general, no
significant differences were observed in
the results for the two methods of quanti-
fication. Acceptable recoveries and pre-
cisions were obtained for all method
parameters at both spiking levels in the
reagent water and Columbus POTW
effluents. For the industrial wastewater,
acrolein apparently decomposed or was
biodegraded despite pH adjustment to a
value of 4.5 prior to spiking, and the
recoveries for this matrix were less than
12 percent for all replicates analyzed.
With the results for reagent water
spiked at the lower level, MDLs of 2.7,
0.7, and 0.5 were calculated for aceto-
nitrile, acrolein, and acrylonitrile, respec-
tively.
Summary and Conclusions
The validation data collected in this
research support the usefulness of
Method 603 for the analysis of acetoni-
trile, acrolein, and acrylonitrile using the
newly established chromatographic con-
ditions. The following conclusions can be
drawn:
• Both of the previously recommended
GC columns are unsuitable for the
separations needed if acetonitrile is to
be included as a method parameter. A
Porapak QS column provides the re-
quired separation of all three analytes.
• The method appears to be precise and
accurate for acetonitrile determination
even though the purging efficiency of
acetonitrile is only about 50 percent.
• No apparent advantage is gained by
the use of an internal standard calibra-
tion procedure. However, the quality
assurance feature of an internal
standard may have merit in some
cases.
• Factors that affect acrolein stability in
aqueous samples are still not well
understood.
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Table 1.
Method
Parameter
Acetonitrile
Acrolein
Acrylonitrile
Method Validation Result* for Reagent Water Using Modified Method 603
Low Level Spike Results
Background
Level, fjg/L
0.9
0.0
1.1
Level
Spiked,
M9/L
10.0
5.0
5.0
Average
Recovery,
W/L
9.5
5.2
5.3
SD1
0.8
0.2
0.1
RSD,2
%
9
4
3
Average
Percent
Recovery
86
104
84
Background
Level, fjg/L
1.3
0.2
1.0
High Level Spike Results
Level
Spiked,
pg/L
100.0
50.0
50.0
A verage
Recovery,
fjg/L
112
51.6
524
RSD,
SD %
12 11
0.7 1 4
1.5 3
A verage
Percent
Recovery
111
103
103
^Standard Deviation.
'Percent Relative Standard Deviation.
Table 2. Method Validation Results for Columbus POTW Secondary Effluent Using Modified Method 603
Low Level Spike Results High Level Spike Results
Method
Parameter
Acetonitrile
Acrolein
Acrylonitrile
Background
Level, fig/L
0.3
0.2
0.9
Level
Spiked,
ng/L
10.0
5.0
20.0
Average
Recovery,
fg/L
10.4
4.2
21.0
SD1
1.5
0.2
0.8
RSD,2
%
14
4
4
Average
Percent
Recovery
101
80
100
Background
Level, fig/L
0.3
0.2
0.9
^Standard Deviation.
'Percent Relative Standard Deviation.
Table 3. Method Validation Results for Industrial Wastewater Using Modified Method 603
Low Level Spike Results
Method
Parameter
Acetonitrile
Acrolein
Acrylonitrile
Background
Level, /jig/L
1.2
0.3
2.1
Level
Spiked,
ug/L
10.0
5.0
10.0
Average
Recovery,
V9/L
11.0
0.4
11.2
SD1
0.3
0.1
0.8
RSD.2
%
3
25
8
Average
Percent
Recovery
98
2
91
Background
Level, fjg/L
0.3
0.6
0.8
Level
Spiked,
fjg/L
100
50
100
Average
Recovery,
ug/L
98
61
107
RSD.
SD %
9 9
1.1 1.8
1.6 1.5
A verage
Percent
Recovery
98
121
106
High Level Spike Results
Level
Spiked,
W/L
100.0
100.0
100.0
Average
Recovery,
ng/L
99
9.9
105
RSD.
SD %
17 17
1.1 11
3.2 3
A verage
Percent
Recovery
99
9
104
^Standard Deviation.
2Percent Relative Standard Deviation.
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S. V. Lucas, T. F. Cole, A. Riggin, and W. M. Cooke are with Battelle-Columbus
Laboratories, Columbus. OH 43201-2693.
James E. Longbottom is the EPA Project Officer (see below).
The complete report, entitled "Evaluation of EPA Method 603 (Modified)," (Order
No. PB85-146 629/AS; Cost: $11.50, 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
* U.S. GOVERNMENT PRINTING OFFICE; 1985 — 569-016/7907
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
Official Business
Penalty for Private Use $300
OCOC329 FS
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