5379
DETERMINATION OF 8ENSULIDE IN-"INDUSTRIAL AND MUNICIPAL
WASTEWATERS BY LIQUID'CHROMATOGRAPHY
001D80101
METHOD 636
1. Scope and Application
1.1 This method covers the determination of bensulide pesticide. The-
following parameter can be determined by this method:
Parameters CAS No.
Bensulide • 741-58-2
1.2 This is a high performance liquid chromatographic (HPLC) method
applicable to the determination of the compound listed above in
municipal and industrial discharges as provided under 40 CFR 136.1.
Any modification of this method beyond those expressly permitted
shall be considered a major modification subject to application and
approval of alternate test procedures under 40 CFR 136.4 and 136.5.
1.3 The method detection limit (MDL, defined in Section 14)
for bensulide compound is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
U.S. Environmental Protection Agency
Region V, Library
230 South Dearborn Street
Chicago, Illinois 60604
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1.4 This method is restricted to use by"or under the supervision of
analysts experienced in the use of liquid chromatography and in
•'
the interpretation of liquid chromatograms. Each analyst must
demonstrate the ability to generate acceptable results with this
method using the procedure described in Sectionr8.2.
1.5 When this method is used to analyze unfamiliar samples for the
compound above, compound identifications should be supported by at
least one additional qualitative technique. This method describes
analytical conditions for a second liquid chromatographic column
*>
that can be used to confirm measurements made with the primary
column.
.2. Summary of Method
2.1 A measured volume of sample, approximately 1 liter, is solvent ex-
tracted with methylene chloride using a separatory funnel. The
methylene chloride extract is dried and exchanged to acetonitrile
during concentration to a volume of 2 ml or less. Liquid chromato-
graphic conditions are described which permit the separation and
measurement of the compounds in the extract by HPLC-UV.l
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead
to discrete artifacts or elevated baselines in liquid chromatograms.
All of these materials must be routinely demonstrated to be free
from interferences under the conditions of the analysis by running
, laboratory reagent blanks as described in Section 8.5.
U,S. EnvfronrnerrtaJ Protection
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3.1.1 Glassware must be scrupulously cleaned2. Clean all glass-
'ware as soon as possible after use by thoroughly rinsing with
the last solvent used in it. Follow by washing with hot water
and detergent and thorough rinsing with tap and reagent water.
Drain dry, and heat in an oven or muffle furnace at 400°C for
15 to 30 min. Some thermally stable materials such as
PCBs may not be eliminated by this treatment. Thorouqh rinsing
with acetone and pesticide quality hexane may be substituted for
the heating. After drying and cooling, seal and store glass-
ware in a clean environment to prevent any accumulation
of dust or other contaminants. Store inverted or capped with
aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to mini-
mize interference problems. Purification of solvents by
distillation in all-glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are coex-
tracted from the sample. The extent of matrix interferences.will
vary considerably from source to source, depending upon the nature
and diversity of the industrial complex or municipality being
sampled. The cleanup procedure in Section II can be used to
overcome these interferences, but unique samples may require
additional cleanup approaches to achieve the MOL listed in Table 1.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this method
has not been precisely defined; however, each chemical compound
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should be^treated as a potentialvhealth hazard. From this view-
point, exposure to these chemicals must be reduced to the lowest
possible level by whatever means available. The laboratory is
"• .
responsible for maintaining a current awareness file of OSHA
regulations regarding the safe handling of the chemicals specified
1n this method. A reference file of material data handling sheets
should also be made available to all personnel involved in the
chemical analysis. Additional references to laboratory safety are
available and have been identified3"5 for the information of the
analyst.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle - Borosilicate or flint glass,
1-liter or 1-quart volume, fitted with screw caps lined
with Teflon. Aluminum foil may be substituted for Teflon
if the sample is not corrosive. The container and cap
liner must be washed, rinsed with acetone or methylene
chloride, and dried before use to minimize,contamination.
5.1.2 Automatic sampler (optional) - Must incorporate glass sample
containers for the collection of a mi'nimum of 250 ml.
Sample containers must be kept refrigerated at 4°C and
protected from light during compositing. If the sampler
uses a peristaltic pump, a minimum length of compressible
silicone rubber tubing may be used. Before use, however,
the compressible tubing should be thoroughly rinsed with
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methanol, followed by repeated rinsings with distilled water
to minimize the potential for"contamination of the sample.
An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for-illustration only.)
5.2.1 Separatory funnel - 2000-mL, with Teflon stopcock.
(] 5.2.2 Drying column - Chromatographic column 400 mm long x 10 mm
v
ID with coarse frit.
5.2.3 Chromatographic column - 400 mm long x 19 mm ID with 250 ml
reservoir at the top and Teflon stopcock (Kontes K-420290 or
equivalent).
5.2.4 Concentrator tube, Kuderna-Danish - 25-mL, graduated (Kontes
K-570050-2525 or equivalent). Calibration must be checked
at the volumes employed in the test. A ground glass stopper
is used to prevent evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Oanish - 500-mL (Kontes
K-570001-0500 or equivalent). Attach to concentrator tube
with springs.
5.2.6 Snyder column, Kuderna-Danish - three-ball macro (Kontes
K-503000-0121 or equivalent).
5.2.7 Snyder column, Kuderna-Oanish - two-ball micro (Kontes
K-569001-0219 or equivalent).
5.2.8 Vials - Amber glass, 5 to 10 ml capacity with Teflon lined
screw-cap.
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5.3 Boiling chips - approximately 10/40 mesh carborundum. Heat to
400eC for 4 hours or extract in a Soxhlet extractor with methylene
chloride. _"'-'.'-'
5.4 Water bath,- Heated, capable of'temperature control (+2gC). The
bath should be used in a hood.
5.5 Balance - Analytical, capable of accurately weighing to the
nearest O.Q001 g.
5.6 Liquid chromatograph - Analytical system complete with liquid
chromatograph and all required accessories including syringes,
analytical columns, detector and strip-chart recorder. A.data
system is recommended for measuring peak areas.
5.6.1 Pump - Isocratic pumping system, constant flow.
5.6.2 Column 1 - Reversed-phase column, 5 micron Spherisorb-ODS,
250 x 4.6 mm or equivalent.
5.6.3 Column 2 - Reversed-phase column, 5 micron Lichrosorb RP-2,
250 x 4.6 mm or equivalent.
5.6.4 Detector - Ultraviolet absorbance detector, 270 nm.
6. Reagents
6.1 Reagent water - Reagent water is defined as a water in which an
interferent is not^observed at the method detection limit of each
parameter of interest.
6.2 Methylene chloride, methanol, acetonitrile, distilled-in-glass
quality or equivalent.
6.3 Sodium sulfate (ACS) Granular, anhydrous; heated in a muffle
furnace at 400°C overnight.
6.4 Sodium phosphate, monobasic, (ACS) crystal.
6.5 IN^Sulfuric Acid, slowly add 2.8 ml of cone. H2S04 (94%) to about
50 ml of distilled water. Dilute to 100 ml with distilled water.
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6.6 IN. Sodium Hydroxide. Dissolved 4.0,-g.rams of NaOH in TOO ml of
distilled water.
6.7 Florisil - PR grade (60/100 mesh). Purchase activated at 1250 F
and store in brown glass bottle. Ta prepare for use, place 150 g
in a wide-mouth jar and heat overnight at 160-170°C. Seal tightly
with Teflon or aluminum foil-lined screw cap and cool to room
temperature.
6.8 Stock standard solutions (1.00 ug/yL) - Stock standard solutions
can be prepared from pure standard materials or purchased as
certified solutions.
6.8.1 Prepare stock standard solutions by accurately weighing
about 0.0100 grams of pure material. Dissolve the material
in distilled-in-glass quality methanol and dilute to volume
in a 10-mL volumetric flask. Larger volumes can be used at
the convenience of the analyst. If compound purity is
certified at 96% or greater, the weight can be used without
correction to calculate the concentration of the stock
standard. Commercially prepared stock standards can be,used
at any concentration if they are certified by the
manufacturer or by an independent source.
6.8.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4°C and protect from light.
Stock standard solutions should be checked frequently for
signs of degradation or evaporation, especially just prior
to preparing calibration standards from them.
6.8.3 Stock standard solutions must be replaced after six months
or sooner if comparison with check standards indicates a
problem.
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7. Calibration -
7.1 Establish liquid chromatographic-operating parameters equivalent to
those indicated 1n Table 1. The liquid chromatographic system can
be calibrated using the external standard technique (Section 7.2)
or the internal standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 For each compound of interest, prepare calibration standards
at a minimum of three concentration levels by adding volumes
of one or more stock standards to a volumetric flask and
diluting to volume with acetonitrile. One of the external
standards should be at a concentration near, but above, the
method detection limit. The other concentrations should
correspond to the expected range of concentrations found in
real samples or should define the working range of .the
detector.
7.2.2 Using injections of 2 to 5 UL of each calibration standard,
tabulate peak height or area responses against the mass
injected. The results can be used to prepare a calibration
curve for each compound. Alternatively, the ratio of the
response to the mass injected, defined as the calibration
factor (CF), can be calculated for each compound at each
standard concentration. If the relative standard deviation
of the calibration factor is less than 10% over the working
range, linearity through the origin can be assumed and the
average calibration factor can be used in place of a
calibration curve.
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7.2.3 The working calibration curve "or calibration factor must be
" -'" >
verified on each working shift by the measurement of one or
more calibration standards. If the response for any
compound varies from the predicted response by more than
+10%, the test must be repeated using a fresh calibration
standard. Alternatively, a new calibration curve or
' calibration factor must be prepared for that compound.
7.3 Internal standard calibration procedure. To use this approach, the
analyst must select one or more internal standards similar in
analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard
is not affected by method or matrix interferences. Due to these
limitations, no internal standard applicable to all samples can be
suggested.
7.3.1 Prepare calibration standards at a minimum of three concen-
tration levels for each compound of interest by adding
volumes of one or more stock standards to a volumetric
*
flask. To each calibration standard, add a known constant
amount of one or more internal standards, and dilute to
volume with acetonitrile. One of the standards should be at
a concentration near, but above, the method detection limit.
The other concentrations should correspond to the expected
range of concentrations found in real samples, or should
define the working range of the detector.
7.3.2 Using injections of 2 to 5 W_ of each calibration standard,
tabulate the peak height or area responses against the
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concentration for each compound and internal standard.
Calculate response factors (RF) for each compound as
follows:
RF « (AsC1s)/(AisCs)
where:
As - Response for the compound to be measured.
A^s = Response for the internal standard.
C-fS s Concentration of the internal standard in ug/L.
Cs = Concentration of the compound to be measured in
ug/L.
If the RF value over the working range is constant, less
than 1(3% relative standard deviation, the RF can be assumed
to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to
plot a calibration curve of response ratios, As/Ajs
against RF.
7.3.3 The working calibration curve or RF must be verified on each
working shift by the measurement of one or more calibration
standards. If the response for any compound varies from the
predicted response by more than J^10%, the test must be
repeated using a fresh calibration standard. Alternatively,
a new calibration curve must be prepared for that compound.
7.4 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the
reagents.
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8. Quality Control • —; -
^•MMB«B*HMHMMBmWMM^««WMM „ - __ jC _
8.1 Each laboratory using this method is required to operate a formal
quality control program. The minimum requirements of this program
consist of ah initial demonstration of laboratory capability and
the analysis of spiked samples as a continuing check on performance.
The laboratory is required to maintain performance records to define
the quality of data that is generated.
8.1.1 Before performing any analyses, the analyst must demonstrate
the ability to generate acceptable accuracy and precision
with this method. This ability is establishd as described
in Section 8.2.
8.1.2 In recognition of the rapid advances occurring in chromatog-
graphy, the analyst is permitted certain options to improve
the separations or lower the cost of measurements. Each
time such modifications to the method are made, the analyst
is required to repeat the procedure in Section 8.2.
8.1.3 The laboratory must spike and analyze a minimum of 10% of
all samples to monitor continuing laboratory performance.
This procedure is described in Section 8.4.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 Select a representative spike concentration for each
compound to be measured. Using stock standards, prepare a
quality control check sample concentrate in methanol 1000
times more concentrated than the selected concentrations.
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8.2.2 Using a pi pet, add 1.00 ml of the check sample concentrate
to each of a minimum of four 1000-mL aliquots of reagent
water. A representative wastewater may be used in place of
the reagent water, but one or more additional aliquots must '
be analyzed to determine background levels, and the spike
level must exceed twice the background level for the test to
be valid. Analyze the aliquots according to the method
beginning in Section 10.
8.2.3 Calculate the average percent recovery (R), and the standard
*
deviation of the percent recovery (s), for the results.
Wastewater background corrections must be made before R and
s calculations are performed.
8.2.4 Using the appropriate data from Table 2, determine the
recovery and single operator precision expected for the
method, and compare these results to the values measured in
Section 8.2.3. If the data are not comparable, the analyst
must review potential problem areas and repeat the test.
8.3 The analyst must calculate method performance criteria and define
the performance of the laboratory for each spike concentration and
parameter being measured.
8.3.1 Calculate upper and lower control limits for method
performance as follows:
Upper Control Limit (UCL) * R + 3 s
Lower Control Limit (LCL) = R - 3 s
where R and s are calculated as in Section 8.2.3. The UCL
and LCL can be used to construct control charts^ that are
useful in observing trends in performance.
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8.3.2 The^laboratory must devel-op-and maintain separate accuracy
statements of laboratory performance for wastewater samples.
An accuracy statement for the method is defined as R +_ s.
The accuracy statement should be developed by the analysis
of four aliquots of wastewater as described in Section
8.2.2, followed by the calculation of R and s. Alternately,
the analyst may use four wastewater data points gathered
through the requirement for continuing quality control in
Section 8.4. The accuracy statements should be updated
with this method. This ability is established as described
regularly6.
8.4 The laboratory is required to collect in duplicate a portion of
their samples to monitor spike recoveries. The frequency of spiked
sample analysis must be at least 10% of all samples or one sample
per month, whichever is greater. One aliquot of the sample must be
spiked and analyzed as described in Section 8.2. If the recovery
for a particular compound does not fall within the control limits
for method performance, the results reported for that compound in
all samples processed as part of the sane set must be qualified as
described in Section 13.3. The laboratory should monitor the
frequency of data so qualified to ensure that it remains at or
below 5%.
8.5 Before processing any samples, the analyst should demonstrate
though the analysis of a 1-liter aliquot of reagent water that all
glassware and reagents interferences are under control. Each time
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a set of samples is extracted or there is a change in reagents, a
laboratory reagent blank should be processed as a safeguard against
laboratory contamination.
8.6 It is recommended that'the laboratory adopt additional quality
assurance practices for use with this method. The specific
practices that are most productive depend upon the needs of the
laboratory and the nature of the samples. Field duplicates may be
analyzed to monitor the precision of the sampling technique. When
doubt exists over the identification of a peak on the chromatogram,
confirmatory techniques such as liquid chromatography with a
dissimilar column, must be used. Whenever possible, the laboratory
should perform analysis of standard reference materials and
participate in relevant performance evaluation studies.
9. Samples Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices? should be followed; however, the bottle must
not be prerinsed with sample before collection. Composite samples
should be collected in refrigerated glass containers in accordance
with the requirements of the program. Automatic sampling equipment
must be as free as possible of Tygon and other potential sources of
contamination.
9.2 The samples must be iced or refrigerated at 4°C from the time of
collection until extraction.
9.3 Adjust the pH of the sample to 6 to 8 with 1N_ sodium hydroxide
or IN sulfuric acid immediately after sampling.
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10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for later
determination of sample volume. Pour the entire sample into a
2-liter separatory funnel. Check the pH of the sample with wide
range pH paper and adjust to 7 with 1 N sodium hydroxide or 1 N
H2S04.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 seconds to rinse the inner walls. Transfer the solvent to
the separatory funnel and extract the sample by shaking the funnel
for 2 min with periodic vent-ing to release excess pressure. Allow
the organic layer to separate from the water phase for a minimum of
10 min. If the emulsion interface between layers is more than one
third the volume of the solvent layer, the analyst must employ
mechanical techniques to complete the phase separation. The
optimum technique depends upon the sample, but may include
stirring, filtration of the emulsion through glass wool,
centrifugation, or other physical methods. Collect the methylene
chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time,
collecting the extract. Perform a third extraction in the same
manner and collect the extract.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 25-mL
concentrator tube to a 500-mL evaporative flask. Other concentra-
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tion devices or techniques may be used in place of the K-D if the
requirements of Section 8.2 are met...
10.5 Pour the combined extract through a drying column containing about
10 era of anhydrous sodium sulfate, and collect the extract in the
K-D concentrator. Rinse the Erlenmeyer flask and column with 20 to
30 ml of methylene chloride to complete the quantitative transfer.
Once the flask rinse has passed through the drying column, rinse
the column with 30 to 40 ml of methylene chloride.
10,6 Add 1 or 2 clean boiling chips to the evaporative flask and attach
a three-ball macro-Snyder column. Prewet the Snyder column by adding
about 1 mL methylene chloride to the top. Place the K-D apparatus
on a hot water bath, 60 to 65°C, so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation, the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent
volume of liquid reaches 1 mL, remove the K-D apparatus and allow
it to drain and cool for at least 10 minutes. If the sample extract
requires no further cleanup, proceed with solvent exchange to
acetonitrile and chromatographic analysis as described in Sections
11.5 and 12 respectively. If the sample requires cleanup, proceed
to Section 10.7.
10.7 Remove the macro-Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 ml of methylene
chloride. A 5-mL syringe is recommended for this operation. Add 1
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or 2 clean boiling chips and attach a two-ball micro-Snyder column
to the concentrator tube. Prewet the micro-Snyder column 'with
methylene chloride and 'concentrate the solvent extract as before.
When an apparent volume of 0.5 ml is reached, or the solution stops
boiling, remove the K-0 apparatus and allow it to drain and cool
for 10 minutes.
10.8 Remove the micro-Snyder column and adjust the volume of the extract
to 1.0 ml with methylene chloride. Stopper the concentrator tube
and store refrigerated if further processing will not be performed
immediately. If the extract is to be stored longer than two days,
transfer the extract to a screw capped vial with a Teflon-lined
cap.
10.9 Determine the original sample volume by refilling the sample bottle
to the mark and transferring the water to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. The cleanup procedure recommended in this method
has been used for the analysis of various clean waters and
industrial effluents. If particular circumstances demand the use
of additional cleanup, the analyst must demonstrate that the
recovery of each compound of interest is no less than 76%.
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11.2 Slurry 10 g of Florisil 1n 100 Si'of methylene chloride which has
x . -•""•'.
been saturated with reagent water, transfer the slurry to a
chromatographic column (Florisil may be retained with a pluo. of qlass
wool). Wash the column with 100 ml of methylene chloride. Use a
column flow rate of 2 to.2.5 mL/min throughout the wash and elution
profiles.
11.3 Add the extract from Section 10.8 to the head of the column. Allow
the solvent to elute from the column until the Florisil is almost
exposed to the air. Elute the column with 50 ml of methylene
chloride.' Discard this fraction.
11.4 Elute the column with 50 mL of 5% acetone in methylene chloride.
Collect this fraction in a K-D apparatus. Concentrate the .column
fraction to 1 mL as described in Sections 10.6 and 10.7.
11.5 Add 15 ml of acetonitrile to the concentrate along with 1 or 2
clean boiling chips. Attach a three-ball micro-Snyder column to
the concentrator tube. Prewet the micro-Snyder column with
acetonitrile and concentrate the solvent extract to an apparent
volume of 1 ml. Allow the K-D apparatus to drain and cool for 10
minutes.
11.6 Transfer the liquid to a 2-mL volumetric flask and dilute to the
mark with acetonitrile. Mix thoroughly prior to analysis. If the
extracts will not be analyzed immediately, they should be
transferred to Teflon sealed screw-cap vials and refrigerated.
Proceed with the liquid chromatographic analysis.
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12. Liquid Chromatography - " - Tt " -
12.1 Table 1 summarizes the recommended operating conditions for the
liquid chrcmatograph. Included in'this table are estimated
-i ~ •• . -
retention times and method detection limits that can be achieved by
this method. An example of the separations achieved by Column 1 •
and Column 2 are shown in Figures 1 and 2. Other HPLC columns,
*
chromatographic conditions, or detectors may be used if the
requirements of Section 8.2 are met.
12.2 Calibrate the liquid chromatographic system daily as described in
Section 7.
12.3 If an internal standard approach is being used, the analyst must
not add the internal standard to the sample extracts until
immediately before injections into the instrument. Mix thoroughly.
12.4 Inject 2 to 5 uL of the sample extract into the sample valve
loop. Record the resulting peak sizes in area or peak heights
units.
12.5 The width of the retention time window used to make identifications
should be based upon measurements of actual retention time
variations of standards over the course of a day. Three times the
standard deviation of a retention time for a compound can be used
to calculate a suggested window size; however, the experience of
the analyst should weigh heavily 1n the interpretation of
chromatograms.
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12.6 If the response for the peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations ,..•••"
13.1 Determine the concentration of individual compounds in the sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak
response using the calibration curve or calibration factor
in Section 7.2.2. The concentration in the sample can be
calculated as follows:
(A){Vt)
Concentration, ug/L = -———>.
where:
A * Amount of'material injected, in nanograms.
V, = Volume of extract 'injected in UL.
Vt - Volume of total extract in UL.
Vs » Volume of water extracted in ml.
13.1.2 If the internal standard calibration procedure was used,
calculate the concentration in the sample using the response
factor (RF) determined in Section 7.3.2 as follows:
(AS)(I$)
Concentration, ug/L -
where:
As = Response for the compound to be measured.
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A-jS » Response for the" internal standard.
Is = Amount of internal standard added to each
extract in ug.
-j -•
V0 * Volume of water extracted, in liters.
13.2 Report results in micrograms per liter without correction for
recovery data. When duplicate and spiked samples are analyzed,
report all data obtained with the sample results.
13.3 For samples processed as part of a set where the laboratory spiked
sample recovery falls outside of the control limits in Section 3.3,
data for the affected compounds must be labeled as suspect.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with
Q
99% confidence that the value is above zero. The MDL concentra-
tions listed in Tabla 1 were obtained using reagent water.1
Similar results were achieved using representative wastewaters.
14.2 This method has been tested for linearity of recovery from sp'iked
reagent water and has been demonstrated to be applicable over the
concentration range from 10 x MOL to 1QOO x MDL.
14.3 In a single laboratory, Battelle Columbus Laboratories, using
spiked wastewater samples, the average recoveries presented in
Table 2 were obtained. Seven replicates of each of two different
wastewaters were spiked and analyzed. The standard deviation of
the percent recovery is also included in Table 2.1
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REFERENCES
1. "Development of Methods for Pesticides in Wastewaters," Report for EPA
Contract 68-03-2956 {In preparation). -
2. ASTM Annual Book of Standards, Part 31, D3694, "Standard Practice for
Preparation of Sample Containers and for Preservation," American Society
for Testing and Materials, Philadelphia, PA, p. 679, 1980.
3. "Carcinogens - Working with Carcinogens," Department of Health, Education,
and Welfare, Public Health Service, Center for Disease Control, National
Institute for Occupational Safety and Health, Publication No. 77-206,
August, 1977.
4. "OSHA Safety and Health Standards, General Industry," (29 CFR 1910),
Occupational Safety and Health Administration, OSHA 2206 (Revised,
January, 1976).
5. "Safety in Academic Chemistry Laboratories," American Chemical Society
Publication, Committee on Chemical Safety, 3rd Edition, 1979.
6. "Handbook for Analytical Quality Control in Water and Wastewater
Laboratories," EPA-600/4-79-019, U. S. Environmental Protection Agency,
Environmental Monitoring and Support Laboratory - Cincinnati, Ohio 45268,
March, 1979.
7. ASTM Annual Book of Standards, Part 31, D3370, "Standard Practice for
Sampling Water," American Society for Testing and Materials, Philadelphia,
PA, p. 76, 1980.
8. Glaser, J. A. et al, "Trace Analysis for Wastewaters," Environmental
Science and Technology, J.5_t 1426 (1981).
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TABLE 1. CHROMATOGRAPHIC.CONDITIONS AND METHOD DETECTION LIMITS
Retention Time (min.) Method Detection Limit
Parameter Column 1Column 2 (ug/L)
Bensulide 14.1 7.2 1.6
Bensulide
Column 1 conditions: Spherisorb-ODS, 5 micron, 250 x 4.6 mm; 1 mL/min. flow;
55/45 acetonitrile/water.
Column 2 conditions: Lichrosorb RP-2, 5 micron, 250 x 4.6 mm; 1 mL/min. flow;
60/40 acetonitrile/water.
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TABLE 2. SINGLE LABORATORY ACCURACY AND PRECISIONa)
Parameter
Bensul Ide
Average
Percent
Recovery.
86
76
Standard .
Deviation,
18
18
Spike
Level
25
250
Number
of
Analyses
7
7
Matrix
Type(b)
1
i \
(a) Column 1 conditions were used.
(b) 1 » Relevant Industrial wastewater,
U.S. Environmental Protection Agency
Region V, Library
230 South Dearborn Street
Chicago, Iflinofs 60604
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