METHOD 505

ANALYSIS OF ORGAN OH ALIDE PESTICIDES AND
COMMERCIAL POLYCHLORINATED BIPHENYL (PCB) PRODUCTS
IN WATER BY MICROEXTRACTION AND GAS CHROMATOGRAPHY

Revision 2.0

T. W. Winfield — Method 505, Revision 1.0 (1986)
T. W. Winfield — Method 505, Revision 2.0 (1989)

ENVIRONMENTAL MONITORING SYSTEMS LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268

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METHOD 505

ANALYSIS OF ORGANOHALIDE PESTICIDES AND COMMERCIAL
POLYCHLORINATED BIPHENYL (PCB) PRODUCTS IN WATER BY
MICROEXTRACTION AND GAS CHROMATOGRAPHY

SCOPE AND APPLICATION

1.1 This method is applicable to the determination of the following analytes in
finished drinking water, drinking water during intermediate stages of
treatment, and the raw source water:13

Analyte

Chemical Abstract Services
Registry Number

Alachlor

15972-60-8

Aldrin

309-00-2

Atrazine

1912-24-9

Chlordane

57-74-9

alpha-Chlorodane

5103-71-9

gamma-Chlorodane

5103-74-2

Dieldrin

60-57-1

Endrin

72-20-8

Heptachlor

76-44-8

Heptachlor Epoxide

1024-57-3

Hexachlorobenzene

118-74-1

Hexachlorocyclopentadiene

77-74-4

Lindane

58-89-9

Methoxychlor

72-43-5

cis-Nonachlor

5103-73-1

trans-Nonachlor

39765-80-5

Simazine

122-34-9

Toxaphene

8001-35-2

Aroclor 1016

12674-11-2

Aroclor 1221

11104-28-2

Aroclor 1232

11141-16-5

Aroclor 1242

53469-21-9

Aroclor 1248

12672-29-6

Aroclor 1254

11097-69-1

Aroclor 1260

11096-82-5

1.2 For compounds other than the above mentioned analytes or for other sample
sources, the analyst must demonstrate the applicability of the method by
collecting precision and accuracy data on fortified samples (i.e., groundwater,
tap water) and provide qualitative confirmation of results by Gas
Chromatography/Mass Spectrometry (GC/MS), or by GC analysis using
dissimilar columns.4 5

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1.3	Method detection limits (MDL)6for the above organohalides and Aroclors have
been experimentally determined (Section 13.1). Actual detection limits are
highly dependent upon the characteristics of the gas chromatographic system
used (e.g., column type, age, and proper conditioning; detector condition; and
injector mode and condition).

1.4	This method is restricted to use by or under the supervision of analysts
experienced in the use of GC and in the interpretation of gas chromatograms.
Each analyst must demonstrate the ability to generate acceptable results with
this method using the procedure described in Section 11.0.

1.5	Analytes that are not separated chromatographically, i.e., analytes which have
very similar retention times, cannot be individually identified and measured in
the same calibration mixture or water sample unless an alternative technique
for identification and quantitation is used (Section 11.4).

1.6	When this method is used to analyze unfamiliar samples for any or all of the
analytes above, analyte identifications should be confirmed by at least one
additional qualitative technique.

1.7	Degradation of Endrin, caused by active sites in the injection port and GC
columns, may occur. This is not as much a problem with new capillary
columns as with packed columns. However, high boiling sample residue in
capillary columns will create the same problem after injection of sample
extracts.

2.0 SUMMARY OF METHOD

2.1	Thirty-five mL of sample are extracted with 2 mL of hexane. Two |iL of the
extract are then injected into a gas chromatograph equipped with a linearized
electron capture detector for separation and analysis. Aqueous calibration
standards are extracted and analyzed in an identical manner in order to
compensate for possible extraction losses.

2.2	The extraction and analysis time is 30-50 minutes per sample depending upon
the analytes and the analytical conditions chosen. (See Section 6.9.)

3.0 DEFINITIONS

3.1	Laboratory Duplicates (LD1 and LD2) — Two sample aliquots taken in the
analytical laboratory and analyzed separately with identical procedures.
Analyses of LD1 and LD2 give a measure of the precision associated with
laboratory procedures, but not with sample collection, preservation, or storage
procedures.

3.2	Field Duplicates (FD1 and FD2) — Two separate samples collected at the same
time and place under identical circumstances and treated exactly the same
throughout field and laboratory procedures. Analyses of FD1 and FD2 give a

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measure of the precision associated with sample collection, preservation and
storage, as well as with laboratory procedures.

3.3	Laboratory Reagent Blank (LRB) — An aliquot of reagent water that is treated
exactly as a sample including exposure to all glassware, equipment, solvents,
reagents, internal standards, and surrogates that are used with other samples.
The LRB is used to determine if method analytes or other interferences are
present in the laboratory environment, the reagents, or the apparatus.

3.4	Field Reagent Blank (FRB) — Reagent water placed in a sample container in the
laboratory and treated as a sample in all respects, including exposure to
sampling site conditions, storage, preservation and all analytical procedures.
The purpose of the FRB is to determine if method analytes or other
interferences are present in the field environment.

3.5	Laboratory Performance Check Solution (LPC) — A solution of method
analytes, surrogate compounds, and internal standards used to evaluate the
performance of the instrument system with respect to a defined set of method
criteria.

3.6	Laboratory Fortified Blank (LFB) — An aliquot of reagent water to which
known quantities of the method analytes are added in the laboratory. The LFB
is analyzed exactly like a sample, and its purpose is to determine whether the
methodology is in control, and whether the laboratory is capable of making
accurate and precise measurements at the required method detection limit.

3.7	Laboratory Fortified Sample Matrix (LFM) — An aliquot of an environ- mental
sample to which known quantities of the method analytes are added in the
laboratory. The LFM is analyzed exactly like a sample, and its purpose is to
determine whether the sample matrix contributes bias to the analytical results.
The background concentrations of the analytes in the sample matrix must be
determined in a separate aliquot and the measured values in the LFM
corrected for background concentrations.

3.8	Stock Standard Solution — A concentrated solution containing a single certified
standard that is a method analyte, or a concentrated solution of a single
analyte prepared in the laboratory with an assayed reference compound. Stock
standard solutions are used to prepare primary dilution standards.

3.9	Primary Dilution Standard Solution — A solution of several analytes prepared
in the laboratory from stock standard solutions and diluted as needed to
prepare calibration solutions and other needed analyte solutions.

3.10	Calibration Standard (CAL) — A solution prepared from the primary dilution
standard solution and stock standard solutions of the internal standards and
surrogate analytes. The CAL solutions are used to calibrate the instrument
response with respect to analyte concentration.

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3.11 Quality Control Sample (QCS) — A sample matrix containing method analytes
or a solution of method analytes in a water miscible solvent which is used to
fortify reagent water or environmental samples. The QCS is obtained from a
source external to the laboratory, and is used to check laboratory performance
with externally prepared test materials.

INTERFERENCES

4.1	Method interferences may be caused by contaminants in solvents, reagents,
glassware and other sample processing apparatus that lead to discrete artifacts
or elevated baselines in gas chromatograms. All reagents and apparatus must
be routinely demonstrated to be free from interferences under the conditions of
the analysis by running laboratory reagent blanks as described in Section 10.2.

4.1.1	Glassware must be scrupulously cleaned.2 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 wih tap and reagent water. Drain dry, and heat in an oven or
muffle furnace at 400°C for one hour. Do not heat volumetric ware.
Thermally stable materials might not be eliminated by this treatment.
Thorough rinsing with acetone may be substituted for the heating.

After drying and cooling, seal and store glassware in a clean
environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.

4.1.2	The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required. WARNING: When a solvent is
purified, stabilizers put into the solvent by the manufacturer are
removed thus potentially making the solvent hazardous. Also, when a
solvent is purified, preservatives put into the solvent by the
manufacturer are removed thus potentially reducing the shelf-life.

4.2	Interfering contamination may occur when a sample containing low
concentrations of analytes is analyzed immediately following a sample
containing relatively high concentrations of analytes. Between-sample rinsing
of the sample syringe and associated equipment with hexane can minimize
sample cross contamination. After analysis of a sample containing high
concentrations of analytes, one or more injections of hexane should be made to
ensure that accurate values are obtained for the next sample.

4.3	Matrix interferences may be caused by contaminants that are coextracted from
the sample. Also, note that all the analytes listed in the scope and application
section are not resolved from each other on any one column, i.e., one anlayte
of interest may be an interferent for another analyte of interest. The extent of
matrix interferences will vary considerably from source to source, depending
upon the water sampled. Cleanup of sample extracts may be necessary.
Positive identifications should be confirmed (Section 11.4).

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4.4	It is important that samples and working standards be contained in the same
solvent. The solvent for working standards must be the same as the final
solvent used in sample preparation. If this is not the case, chromatographic
comparability of standards to sample may be affected.

4.5	Caution must be taken in the determination of endrin since it has been
reported that the splitless injector may cause endrin degradation7. The analyst
should be alerted to this possible interference resulting in an erratic response
for endrin.

4.6	Variable amounts of pesticides and commercial PCB products from aqueous
solutions adhere to glass surfaces. It is recommended that sample transfers
and glass surface contacts be minimized.

4.7	Aldrin, hexachlorocyclopentadiene and methoxychlor are rapidly oxidized by
chlorine. Dechlorination with sodium thiosulfate at time of collection will
retard further oxidation of these compounds.

WARNING: An interfering, erratic peak has been observed within the
retention window of heptachlor during many analyses of reagent, tap, and
groundwater. It appears to be related to dibutyl phthalate; however, the
specific source has not yet been definitively determined. The observed
magnitude and character of this peak randomly varies in numerical value from
successive injections made from the same vial.

SAFETY

5.1	The toxicity and carcinogenicity of chemicals used in this method have not
been precisely defined; each chemical should be treated as a potential health
hazard, and exposure to these chemicals should be minimized. Each
laboratory is responsible for maintaining awareness of OSHA regulations
regarding safe handling of chemicals used in this method. Additional
references to laboratory safety are available for the information of the
analyst.8-10

5.2	The following organohalides have been tentatively classified as known or
suspected human or mammalian carcinogens: aldrin, commercial PCB
products, chlordane, dieldrin, heptachlor, hexachlorobenzene, and toxaphene.
Pure standard materials and stock standard solutions of these compounds
should be handled in a hood or glovebox.

WARNING: When a solvent is purified, stabilizers put into the solvent by the
manufacturer are removed thus potentially making the solvent hazardous.

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APPARATUS AND EQUIPMENT

6.1	Sample Containers — 40 mL screw cap vials (Pierce #13075 or equivalent) each
equipped with a size 24 cap with a flat, disc-like TFE facing backed with a
polyethylene film/foam extrusion (Fisher #02-883-3F or equivalent). Prior to
use, wash vials and septa with detergent and rinse with tap and distilled
water. Allow the vials and septa to air dry at room temperature, place the
vials in a 400°C oven for one hour, then remove and allow to cool in an area
known to be free of organics.

6.2	Vials — auto sampler, screw cap with septa, 1.8 mL, Varian #96-000099-00 or
equivalent or any other autosampler vials not requiring more than 1.8 mL
sample volumes.

6.3	Auto Sampler — Hewlett-Packard 7671 A, or equivalent.

6.4	Micro Syringes — 10 and 100 |iL.

6.5	Micro Syringe — 25 |iL with a 2-inch by 0.006-inch needle - Hamilton 702N or
equivalent.

6.6	Pipettes — 2.0 and 5.0 mL transfer.

6.7	Volumetric Flasks — 10 and 100 mL, glass stoppered.

6.8	Standard Solution Storage Containers -15 mL bottles with PTFE-lined screw
caps.

6.9	Gas Chromatograph — Analytical system complete with temperature
programmable GC suitable and split/splitless injector for use with capillary
columns and all required accessories including syringes, analytical columns,
gases, a linearized electron capture detector and stripchart recorder. A data
system is recommended for measuring peak areas. Table 1 lists retention times
observed for method analytes using the columns and analytical conditions
described below.

6.9.1	Three gas chromatographic columns are recommended. Column 1
(Section 6.9.2) should be used as the primary analytical column unless
routinely occurring analytes are not adequately resolved. Validation
data presented in this method were obtained using this column.
Columns 2 and 3 are recommended for use as confirmatory columns
when GC/MS confirmation is not available. Alternative columns may
be used in accordance with the provisions described in Section 10.3.

6.9.2	Column 1 (Primary Column) — 0.32 mm ID x 30 M long fused silica
capillary with chemically bonded methyl polysiloxane phase (DB-1,

1.0 |im film, or equivalent). Helium carrier gas flow is about 25 cm/sec
linear velocity, measured at 180° with 9 psi column head pressure. The

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oven temperature is programmed from 180-260°C at 4°C/min and held
at 260°C until all expected compounds have eluted. Injector
temperature: 200°C. Splitless Mode: 0.5 minutes. Detector
temperature: 290°C. Sample chromatograms for selected pesticides are
presented in Figures 1 and 2. Chromatograms of the Aroclors,
toxaphene, and technical chlordane are presented in Figures 3 through
11.

6.9.3	Column 2 (alternative column 1) — 0.32 mm ID x 30 M long fused silica
capillary with a 1:1 mixed phase of dimethyl silicone and polyethylene
glycol (Durawax-DX3, 0.25 |im film, or equivalent). Helium carrier gas
flow is about 25 cm/sec linear velocity and oven temperature is
programmed from 100-210°C at 8°C/min, and held at 210°C until all
expected compounds have eluted. Then the post temperature is
programmed to 240°C at 8°C/min for five minutes.

6.9.4	Column 3 (alternative column 2) — 0.32 mm ID x 25 M long fused silica
capillary with chemically bonded 50:50 Methyl-Phenyl silicone (OV-17,
1.5 |im film thickness, or equivalent). Helium carrier gas flow is about
40 cm/sec linear velocity and oven temperature is programmed from
100-260°C at 4°C/min and held at 260°C until all expected compounds
have eluted.

REAGENTS AND CONSUMABLE MATERIALS

WARNING: When a solvent is purified stabilizers put into the solvent by the
manufacturer are removed thus potentially making the solvent hazardous. Also,
when a solvent is purified, preservatives put into the solvent by the manufacturer are
removed thus potentially making the shelf-life short.

7.1 Reagents

7.1.1	Hexane extraction solvent — UV grade, Burdick and Jackson #216 or
equivalent.

7.1.2	Methyl alcohol — ACS reagent grade, demonstrated to be free of
analytes.

7.1.3	Sodium chloride, NaCl — ACS reagent grade, for pretreatment before
use, pulverize a batch of NaCl and place in a muffle furnace at room
temperature. Increase the temperature to 400°C and hold for 30
minutes. Place in a bottle and cap.

7.1.4	Sodium thiosulfate, Na2S203 — ACS reagent grade, for preparation of
solution (0.04 g/mL), mix 1 g of Na2S203 with reagent water and bring
to 25 mL volume in a volumetric flask.

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7.2	Reagent Water — Reagent water is defined as water free of interference when
employed in the procedure described herein.

7.2.1	A Millipore Super-Q Water System or its equivalent may be used to
generate deionized reagent water.

7.2.2	Test reagent water each day it is used by analyzing it according to
Section 11.0.

7.3	Stock Standard Solutions — These solutions may be obtained as certified
solutions or prepared from pure standard materials using the following
procedures:

7.3.1	Prepare stock standard solutions (5000 |ig/mL) by accurately weighing
about 0.0500 g of pure material. Dissolve the material in methanol and
dilute to volume in a 10 mL volumetric flask. Larger volumes can be
used at the convenience of the analyst. When compound purity is
assayed to be 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.

7.3.2	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.

7.3.3	Stock standard solutions must be replaced after six months, or sooner if
comparison with check standards indicates a problem.

7.4	Primary Dilution Standard Solutions — Use stock standard solutions to prepare
primary dilution standard solutions that contain the analytes in methanol. The
primary dilution standards should be prepared at concentrations that can be
easily diluted to prepare aqueous calibra- tion standards (Section 9.1.1) that
will bracket the working concentra- tion range. Store the primary dilution
standard solutions with minimal headspace and check frequently for signs of
deterioration or evaporation, especially just before preparing calibration
standards. The storage time described for stock standard solutions in
Section 7.3.3 also applies to primary dilution standard solutions.

SAMPLE COLLECTION. PRESERVATION. AND STORAGE

8.1 Sample Collection

8.1.1 Collect all samples in 40 mL bottles into which 3 mg of sodium

thiosulfate crystals have been added to the empty bottles just prior to
shipping to the sampling site. Alternately, 75 |iL of freshly prepared

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sodium thiosulfate solution (0.04 g/mL) may be added to empty 40 mL
bottles just prior to sample collection.

8.1.2	When sampling from a water tap, open the tap and allow the system to
flush until the water temperature has stabilized (usually about

10 minutes). Adjust the flow to about 500 mL/min and collect samples
from the flowing stream.

8.1.3	When sampling from a well, fill a wide-mouth bottle or beaker with
sample, and carefully fill 40 mL sample bottles.

8.2	Sample Preservation

8.2.1 The samples must be chilled to 4°C at the time of collection and

maintained at that temperature until the analyst is prepared for the
extraction process. Field samples that will not be received at the
laboratory on the day of collection must be packaged for shipment with
sufficient ice to insure that they will be maintained at 4°C until arrival
at the laboratory.

8.3	Sample Storage

8.3.1	Store samples and extracts at 4°C until extraction and analysis.

8.3.2	Extract all samples as soon as possible after collection. Results of
holding time studies suggest that all analytes with the possible
exception of heptachlor were adequately stable for 14 days when stored
under these conditions. In general, heptachlor showed inconsistent
results. If heptachlor is to be determined, samples should be extracted
within seven days of collection. Analyte stability may be affected by
the matrix; therefore, the analyst should verify that the preservation
technique is applicable to the samples under study.

CALIBRATION AND STANDARDIZATION

9.1 Establish GC operating parameters equivalent to those indicated in Section 6.9.

WARNING: Endrin is easily degraded in the injection port if the injection port
or front of the column is dirty. This is the result of buildup of high boiling
residue from sample injection. Check for degradation problems by injecting a
mid-level standard containing only endrin. Look for the degradation products
of endrin (endrin ketone and endrin aldehyde). If degradation of endrin
exceeds 20%, take corrective action before proceeding with calibration.

Calculate percent breakdown as follows:

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Total endrin degradation peak area (endrin aldehyde + endrin ketone) x
Total endrin peak area (endrin + endrin aldehyde + endrine ketone)

At least three calibration standards are needed; five are recommended. One
should contain analytes at a concentration near but greater than the method
detection limit for each compound; the other two should be at concentrations
that bracket the range expected in samples. For example, if the MDL is
0.01 Hg/L, and a sample expected to contain approximately 0.10 Hg/L is to be
analyzed, aqueous standards should be prepared at concentrations of
0.02 Hg/L, 0.10 Hg/L, and 0.20 ]ig/L.

9.2.1	To prepare a calibration standard (CAL), add an appropriate volume of
a secondary dilution standard to a 35 mL aliquot of reagent water in a
40 mL bottle. Do not add less than 20 |iL of an alcoholic standard to
the reagent water. Use a 25 |iL micro syringe and rapidly inject the
alcoholic standard into the middle point of the water volume. Remove
the needle as quickly as possible after injection. Mix by inverting and
shaking the capped bottle several times. Aqueous standards must be
prepared fresh daily.

9.2.2	Starting with the standard of lowest concentration, prepare, extract, and
analyze each calibration standard beginning with Section 11.2 and
tabulate peak height or area response versus the concentration in the
standard. The results are to be used to prepare a calibration curve for
each compound by plotting the peak height or area response versus the
concen- tration. Alternatively, if the ratio of concentration to response
(calibration factor) is a constant over the working range (20% RSD or
less), linearity to the origin can be assumed and the average ratio or
calibration factor can be used in place of a calibration curve.

9.2.3	The working calibration curve or calibration factor must be verified on
each working day by the measurement of one or more calibration
standards. If the response for an analyte varies from the predicted
response by more than ±20%, the test must be repeated using a fresh
calibration standard. If the results still do not agree, generate a new
calibration curve or use a single point calibration standard as described
in Section 9.2.4.

9.2.4	Single point calibration is an acceptable alternative to a calibration
curve. Prepare single point standards from the secondary dilution
standard solutions. The single point calibration standard should be
prepared at a concentration that produces a response close (±20% or
less) to that of the unknowns. Do not use less than 20 |iL of the
secondary dilution standard solution to produce a single point
calibration standard in reagent water.

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9.3 Instrument Performance — Check the performance of the entire analytical

system daily using data gathered from analyses of laboratory reagent blanks
(LRB), (CAL), laboratory duplicate samples (LD1 and LD2), and the laboratory
performance check solution (LPC) (Section 10.6).

9.3.1	Significant peak tailing in excess of that shown for the target
compounds in the method chromatograms (Figures 1 through 11) must
be corrected. Tailing problems are generally traceable to active sites on
the GC column, improper column installa- tion, or operation of the
detector.

9.3.2	Check the precision between replicate analyses. Poor precision is
generally traceable to pneumatic leaks, especially at the injection port.
If the GC system is apparently performing acceptably but with
decreased sensitivity, it may be necessary to generate a new curve or
set of calibration factors to verify the decreased responses before
searching for the source of the problem.

9.3.3	Observed relative area responses of endrin (See Section 4.5) must meet
the following general criteria:

9.3.3.1	The breakdown of endrin into its aldo and keto forms must be
adequately consistent during a period in which a series of
analyses is made. Equivalent relative amounts of breakdown
should be demonstrated in the LRB, LPC, LFB, CAL and QCS.
Consistent breakdown resulting in these analyses would suggest
that the breakdown occurred in the instrument system and that
the methodology is in control.

9.3.3.2	Analyses of laboratory fortified matrix (LFM) samples must also
be adequately consistent after corrections for potential
background concentrations are made.

10.0 QUALITY CONTROL

10.1	Minimum quality control (QC) requirements are initial demonstration of
laboratory capability, analysis of laboratory reagent blanks (LRB), laboratory
fortified blanks (LFB), laboratory fortified sample matrix (LFM), and quality
control samples (QCS).

10.2	Laboratory Reagent Blanks — Before processing any samples, the analyst must
demonstrate that all glassware and reagent interfer- ences are under control.
Each time a set of samples is extracted or reagents are changed, an LRB must
be analyzed. If within the retention time window of any analyte the LRB
produces a peak that would prevent the determination of that analyte,
determine the source of contamination and eliminate the interference before
processing samples.

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10.3 Initial Demonstration of Capability

10.3.1 Select a representative concentration (about 10 times MDL or at the

regulatory Maximum Contaminant Level, whichever is lower) for each
analyte. Prepare a primary dilution standard solution (in methanol)
containing each analyte at 1000 times selected concentration. With a
syringe, add 35 |iL of the concentrate to each of at least four 35 mL
aliquots of reagent water, and analyze each aliquot according to
procedures beginning in Section 11.0.

10.3.2 For each analyte the recovery value should for at least three out of four
consecutively analyzed samples fall in the range of R ±30% (or within
R ±3Sr if broader) using the values for R and ^ for reagent water in
Table 2. For those compounds that meet the acceptance criteria,
performance is considered acceptable and sample analysis may begin.
For those compounds that fail these criteria, initial demonstration
procedures should be repeated.

10.3.3 The initial demonstration of capability is used primarily to preclude a
laboratory from analyzing unknown samples via a new, unfamiliar
method prior to obtaining some experience with it. It is expected that
as laboratory personnel gain experience with this method the quality of
data will improve beyond those required here.

10.4 The analyst is permitted to modify GC columns, GC conditions, or detectors to
improve separations or lower analytical costs. Each time such method
modifications are made, the analyst must repeat the procedures in Section 10.3.

10.5 Assessing Laboratory Performance — Laboratory Fortified Blank (LFB)

10.5.1	The laboratory must analyze at least one LFB per sample set (all
samples extracted within a 24-hour period). If the sample set contains
more than 20 samples, analyze one LFB for every 20 samples. The
fortifying concentration of each analyte in the LFB sample should be
10 times MDL or the MCL, whichever is less. Calculate accuracy as
percent recovery (X;). If the recovery of any analyte falls outside the
control limits (see Section 10.5.2), that analyte is judged out of control,
and the source of the problem should be identified and resolved before
continuing analyses.

10.5.2	Until sufficient data become available from within their own laboratory,
usually a minimum of results from 20-30 analyses, the laboratory may
assess laboratory performance against the control limits in Section 10.3.2
that are derived from the data in Table 2. When sufficient internal
performance data becomes available, develop control limits from the
mean percent recovery (X) and standard deviation (S) of the percent
recovery. These data are used to establish upper and lower control
limits as follows:

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UPPER CONTROL LIMIT = X_+ 3S
LOWER CONTROL LIMIT = X - 3S

After each 5-10 new recovery measurements, new control limits should
be calculated using only the most recent 20-30 data points.

10.5.3	It is recommended that the laboratory periodically determine and
document its detection limit capabilities for analytes of interest.

CAUTION: No attempts to establish low detection limits should be
made before instrument optimization and adequate conditioning of
both the column and the GC system. Conditioning includes the
processing of LFB and LFM samples containing moderate concentration
levels of these analytes.

10.5.4	At least each quarter the laboratory should analyze quality control
samples (QCS) (if available). If criteria provided with the QCS are not
met, corrective action should be taken and documented.

10.6	Assessing Analyte Recovery — Laboratory Fortified Sample Matrix (LFM)

10.6.1	The laboratory must add a known concentration to a minimum of 10%
of the routine samples or one LFM per set, whichever is greater. The
fortified concentration should not be less than the background
concentration of the sample selected for fortification. Ideally the LFM
concentration should be the same as that used for the LFB

(Section 10.5). Periodically, samples from all routine sample sources
should be fortified.

10.6.2	Calculate the percent recovery (R;) for each analyte, corrected for
background concentrations measured in the unfortified sample, and
compare these values to the control limits established in Section 10.5.2
from the analyses of LFBs.

10.6.3	If the recovery of any such analyte falls outside the designated range,
and the laboratory performance for that analyte is shown to be in
control (Section 10.5), the recovery problem encountered with the dosed
sample is judged to be matrix related, not system related. The result
for that analyte in the unfortified sample is labeled suspect/matrix to
inform the data user that the results are suspect due to matrix effects.

10.7	The laboratory may adopt additional quality control 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. For example, field or
laboratory duplicates may be analyzed to assess the precision of the
environmental measurements or field reagent blanks may be used to assess
contamination of samples under site conditions, transportation and storage.

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11.0 PROCEDURE

11.1	Sample Preparation

11.1.1	Remove samples from storage and allow them to equilibrate to room
temperature.

11.1.2	Remove the container caps. Withdraw and discard a 5 mL volume
using a 10 mL graduated cylinder. Replace the container caps and
weigh the containers with contents to the nearest 0.1 g and record these
weights for subsequent sample volume determinations (Section 11.3).

11.2	Extraction and Analysis

11.2.1	Remove the container cap of each sample, and add 6 g NaCl
(Section 7.1.3) to the sample bottle. Using a transfer or automatic
dispensing pipet, add 2.0 mL of hexane. Recap and shake vigorously
by hand for 1 min. Invert the bottle and allow the water and hexane
phases to separate.

11.2.2	Remove the cap and carefully transfer approximately 0.5 mL of hexane
layer into an autosampler vial using a disposable glass pipet.

11.2.3	Transfer the remaining hexane phase, being careful not to include any
of the water phase, into a second autosampler vial. Reserve this second
vial at 4°C for an immediate reanalysis if necessary.

11.2.4	Transfer the first sample vial to an autosampler set up to inject 1-2 |iL
portions into the gas chromatograph for analysis (See Section 6.9 for GC
conditions). Alternately, 1-2 mL portions of samples, blanks, and
standards may be manually injected, although an autosampler is
strongly recommended.

11.3	Determination of Sample Volume in Bottles Not Calibrated

11.3.1	Discard the remaining sample/hexane mixture from the sample bottle.
Shake off the remaining few drops using short, brisk wrist movements.

11.3.2	Reweigh the empty container with original cap and calculate the net
weight of sample by difference to the nearest 0.1 g (Section 11.1.2
minus Section 11.3.2). This net weight (in grams) is equivalent to the
volume (in mL) of water extracted (Section 12.3). By alternately using
40 mL bottles precalibrated at 35 mL levels, the gravimetric steps can
be omitted, thus increasing the speed and ease of this extraction
process.

505-15


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11.4 Identification of Analytes

11.4.1	Identify a sample component by comparison of its retention time to the
retention time of a reference chromatogram. If the retention time of an
unknown compound corresponds, within limits, to the retention time of
a standard compound, then identifiction is considered positive.

11.4.2	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 can be used to calculate a suggested
window size for a compound. However, the experience of the analyst
should weigh heavily in the interpretation of chromatograms.

11.4.3	Identification requires expert judgement when sample components are
not resolved chromatographically. When peaks obviously represent
more than one sample component (i.e., broadened peak with
shoulder(s) or valley between two or more maxima), or any time doubt
exists over the identification of a peak on a chromatogram, appropriate
alternative techniques to help confirm peak identification need be
employed. For example, more positive identification may be made by
the use of an alternative detector which operates on a
chemical/physical principle different from that originally used, e.g.,
mass spectrometry, or the use of a second chromatography column.
Suggested alternative columns are described in Section 6.9.

12.0 CALCULATIONS

12.1	Identify the organohalides in the sample chromatogram by comparing the
retention time of the suspect peak to retention times generated by the
calibration standards and the laboratory fortified blanks. Identify the
multicomponent compounds using all peaks that are characteristic of the
specific compound from chromatograms generated with individual standards.
Select the most sensitive and reproducible peaks to obtain a sum for
calculation purposes (See Table 1).

12.2	Use the single point calibration (Section 9.2.4) or use the calibration curve or
calibration factor (Section 9.2.3) to directly calculate the uncorrected
concentration (Ci) of each analyte in the sample (e.g., calibration factor x
response).

12.3	Calculate the sample volume (Vs) as equal to the net sample weight:

Vs = gross weight (Section 11.1.2) - bottle tare (Section 11.3.2).

505-16


-------
12.4 Calculate the corrected sample concentration as:

Concentration, (ig/L = ^	

12.5 Results should be reported with an appropriate number of significant figures.
Experience indicates that three significant figures may be used for
concentrations above 99 Hg/L, two significant figures for concentrations
between 1-99 Hg/L, and 1 significant figure for lower concentrations.

13.0 ACCURACY AND PRECISION

13.1	Single laboratory (EMSL-Cincinnati) accuracy and precision at several
concentrations in reagent, ground, and tap water matrices are presented in
Table 2.11 These results were obtained from data generated with a DB-1
column.

13.2	This method has been tested by 10 laboratories using reagent water and
groundwater fortified at three concentration levels. Single operator precision,
overall precision, and method accuracy were found to be directly related to the
concentration of the analyte and virtually independent of the sample matrix.
Linear equations to describe the relationships are presented in Table 3.12

14.0 REFERENCES

1.	Glaze, W.W. and Lin, C.C. Optimization of Liquid-Liquid Extraction Methods
for Analysis of Organics in Water, EPA-600/S4-83-052, January 1984.

2.	Henderson, J.E., Peyton, G.R., and Glaze, W.H. (1976). In "Identification and
Analysis of Organic Pollutants in Water" (L.H. Keith ed.), pp. 105-111. Ann
Arbor Sci. Publ, Ann Arbor, Michigan.

3.	Richard, J.J. and Junk, G.A. "Liquid Extraction for Rapid Determination of
Halomethanes in Water," Journal AWWA, 69, 62, January 1977.

4.	"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.

5.	Budde, W.L. and Eichelberger, J.W. "Organic Analyses Using Gas
Chromatography-Mass Spectrometry," Ann Arbor Science, Ann Arbor,
Michigan 1979.

6.	Glaser, J.A. et al. "Trace Analyses for Wastewaters," Environmental Science
and Technology, 15, 1426 (1981).

505-17


-------
7.	Bellar, T.A., Stemmer, P., and Lichtenberg, J.J. "Evaluation of Capillary
Systems for the Analysis of Environmental Extracts," EPA-600/S4-84-004,
March 1984.

8.	"Carcinogens-Working with Carcinogens," Department of Health, Education,
and Welfare, Public Health Service, Center for Disease Control, National
Institute of Occupational Safety and Health, Publication No. 77-206, August
1977.

9.	"OSHA Safety and Health Standards, General Industry," (29 CFR 1910),
Occupational Safety and Health Administration, OSHA 2206, (Revised,

January 1976).

10.	"Safety in Academic Chemistry Laboratories," American Chemical Society
Publication, Committee on Chemical Safety, 3rd Edition, 1979.

11.	Winfield, T., et al. "Analysis of Organohalide Pesticides and Commercial PCB
Products in Drinking Water by Microextraction and Gas Chromatography." In
preparation.

12.	Multilaboratory Method Validation Study #40, conducted by the Quality
Assurance Branch, EMSL-Ci. Report in progress.

505-18


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TABLE 1. RETENTION TIMES FOR METHOD ANALYTES





Retention Time (min)a

Analyte

Primary

Confirm. 1

Confirm. 2

Hexachlorocyclopentadiene

5.5

6.8



5.2

Simazine

10.9

25.7



19.9

Atrazine

11.2

22.6



19.6

Hexachlorobenzene

11.9

13.4



15.6

Lindane

12.3

18.4



18.7

Alachlor

15.1

19.7



21.1

Heptachlor

15.9

17.5



20.0

Aldrin

17.6

18.4



21.4

Heptachlor Epoxide

19.0

24.6



24.6

gamma-Chlordane

19.9

25.9



26.0

alpha-Chlordane

20.9

26.6



26.6

trans-Nonachlor

21.3

24.8



26.3

Dieldrin

22.1

45.1



27.8

Endrin

23.2

33.3



29.2

cis-Nonachlor

24.3

39.0



30.4

Methoxychlor

30.0

58.5



36.4



Primary5







Aroclor 1016

13.6, 14.8,

15.2, 16.2, 17.7



Aroclor 1221

7.7, 9.0, 15.9, 19.1, 24.7



Aroclor 1232

11.2, 14.7,

13.6, 15.2,

17.7



Aroclor 1242

11.2, 13.6,

14.7, 15.2,

17.7, 19.8

Aroclor 1248

14.8, 16.2,

17.1, 17.7,

19.8,

22.0

Aroclor 1254

19.1, 21.9,

23.4, 24.9,

26.7



Aroclor 1260

23.4, 24.9,

26.7, 28.2,

29.9, 32.6

Chlordane

15.1, 15.9,

20.1, 20.9,

21.3



Toxaphene

21.7, 22.5,

26.7, 27.2





aColumns and analytical conditions are described in Sections 6.9.2, 6.9.3, and 6.9.4.
bColumn and conditions described in Section 6.9.2. More than one peak listed does not
implicate the total number of peaks characteristic of the multi-component analyte. Listed
peaks indicate only the ones chosen for summation in the quantification.

505-19


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TABLE 2. SINGLE LABORATORY ACCURACY, PRECISION AND METHOD
DETECTION LIMITS (MDLS) FOR ANALYTES FROM REAGENT WATER,
GROUNDWATER, AND TAP WATER3

Accuracy and Standard Deviation Data

Analyte

Rg/L

Concen-
tration*
|Jg/L

Reagent Water
Rc SRd

Groundwater
R SR

Tap Water
R SR

Aldrin

0.075

0.15

86

9.5

100

11.0

69

9.0

Alachlor

0.225

0.50

102

13.4

-

-

-

-

Aldrin

0.007

0.05

106

20.0

86

16.3

-

-

Atrazine

2.4

5.0

85

16.2

95

7.3

108

10.9





20.0

95

5.2

86

9.1

91

3.1

alpha-Chlordane

0.006

0.06

95

3.5

83

4.4

85

7.1





0.35

86

17.0

94

10.2

91

2.4

gamma-Chlordane

0.012

0.06

95

0.4

86

5.3

83

14.7





0.35

86

18.5

95

14.5

91

6.0

Chlordane

0.14

0.17

NA

8.0

-

-

105

12.4





3.4

NA

3.6

-

-

95

9.6

Dieldrin

0.012

0.10

87

17.1

67

10.1

92

15.7





3.6

114

9.1

94

8.6

81

14.0

Endrin

0.063

0.10

119

29.8

94

20.2

106

14.0





3.6

99

6.5

100

11.3

85

12.4

Heptachlor

0.003

0.032

77

10.2

37

6.8

200

22.6





1.2

80

7.4

71

9.8

106

16.8

Heptachlor Epoxide

0.004

0.04

100

15.6

90

14.2

112

7.5





1.4

115

6.6

103

6.9

81

5.9

Hexachlorobenzene

0.002

0.003

104

13.5

91

10.9

100

15.6





0.09

103

6.6

101

4.4

88

13.4

Hexachlorocyclo-

















pentadiene

0.13

0.15

73

5.1

87

5.1

191

18.5





0.35

73

11.7

69

4.8

109

14.3

Lindane

0.003

0.03

91

6.5

88

7.7

103

8.1





1.2

111

5.0

109

3.4

93

18.4

Methoxychlor

0.96

2.10

100

21.0

-

-

-

-





7.03

98

10.9

-

-

-

-

cis-Nonachlor

0.027

0.06

110

15.2

101

7.2

93

14.3





0.45

82

21.3

93

18.3

87

5.4

trans-Nonachlor

0.011

0.06

95

9.6

83

7.1

73

4.1





0.35

86

21.8

94

17.2

86

5.1

Simazine

6.8

25

99

8.3

97

9.2

102

13.4





60

65

3.6

59

18.0

67

6.2

Toxaphene

1.0

10

NA

12.6

-

-

110

9.5





80

NA

15.3

-

-

114

13.5

Aroclor 1016

0.08

1.0

NA

6.6

-

-

97

7.5

Aroclor 1221

15.0

180

NA

8.3

-

-

92

9.6

Aroclor 1232

0.48

3.9

NA

13.5

—

—

86

7.3

505-20


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TABLE 2. SINGLE LABORATORY ACCURACY, PRECISION AND METHOD
DETECTION LIMITS (MDLS) FOR ANALYTES FROM REAGENT WATER,
GROUNDWATER, AND TAP WATER3

Accuracy and Standard Deviation Data

Analyte

Rg/L

Concen-
tration*
|Jg/L

Reagent Water
Rc SRd

Groundwater
R SR

Tap Water
R SR

Aroclor 1242

0.31

4.7

NA

6.0

- -

96

7.4

Aroclor 1248

0.102

3.6

NA

11.5

-

-

-





3.4

-

-

-

84

9.9

Aroclor 1254

0.102

1.8

NA

10.4

- -

-

-





1.7

-

-

-

85

11.8

Aroclor 1260

0.189

2.0

NA

20.7

-

-

-





1.8

NA

—

— —

88

19.8

NA = Not applicable. A separate set of aqueous standards was not analyzed, and the
response factor for reagent water was used to calculate a recovery for the tap water matrix.
aData corrected for amount detected in blank and represent the mean of five to eight
samples.

bMDL = method detection limit in sample in Hg/L; calculated by multiplying standard

deviation (S) times the students' t value appropriate for a 99% confidence level and a

standard deviation estimate with n-1 degrees of freedom.

CR = average percent recovery.

dSR = Standard deviation about percent recovery.

*Refers to concentration levels used to generate R and SR data for the three types of water
Matrices, not for MDL determinations.

- = No analyses conducted.

505-21


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TABLE 3. METHOD ACCURACY AND PRECISION AS FUNCTIONS OF
CONCENTRATION—METHOD 505

REAGENT WATER



Applicable

Accuracy as

Single Analyst

Overall



Cone. Range

Recovery X

Precision Sr

Precision S

Parameter

(Pg/L)

(l-ig/L)



(Pg/L)

(l-ig/L)

Atrazine

(3.06-45.90)

1.122C+0.97

0.000

+ 1.21

0.045

+2.23

Simazine

(12.55-50.20)

0.892C+1.446

-0.049

+3.52

0.209

+ 1.23

Hexachlorobenzene

(0.01-0.37)

1.028C-0.00

0.108

+0.00

0.227

+0.00

Lindane

(0.04-1.39)

1.009C-0.00

0.057

+0.01

0.142

+0.00

Alachlor

(0.50-37.50)

1.004C-0.08

0.077

+0.10

0.105

+0.16

Heptachlor

(0.04-1.41)

1.002C+0.02

0.107

+0.01

0.211

+0.02

Aldrin

(0.04-1.42)

1.066C+0.00

0.031

+0.02

0.264

-0.00

Heptachlor epoxide

(0.04-1.42)

0.952C+0.00

0.032

+0.02

0.129

+0.02

Dieldrin

(0.10-7.53)

1.027C+0.00

0.091

+0.01

0.198

+0.02

Endrin

(0.10-7.50)

0.958C+0.01

0.116

+0.01

0.136

+0.02

Methoxychlor

(0.20-15.00)

0.950C+0.15

0.115

+0.12

0.125

+0.20

Chlordane

(0.51-50.90)

1.037C+0.06

0.084

+0.06

0.125

+0.19

Toxaphene

(5.63-70.40)

1.087C+0.24

0.131

-0.31

0.269

+0.69

5PCB-1016

(0.50-49.80)

0.856C+0.31

0.106

+0.31

0.147

+0.45

PCB-1254

(0.50-50.40)

0.872C-0.01

0.122

+0.11

0.281

+0.05

_*The concentration range applicable to the multi-laboratory study from which the data was generated.
X

X


-------
TIME (MIN)

Figure 1. Hexane spiked at 7.71 ug/L with heptachl6tr and lindane; 9.14 ug/L with heptachlor epoxide;

11.4 ug/L with aldrln and hexachlorobenzene; 23 ug/L with butachlor. chlorpyrtfos. chlorpyrlfos-
methyl, dlclobenll, dleldrln, endrln, metolochlor, and propachlor; and 44.9 ug/L with

methoxychlor.


-------
COLIHN: Fused silica capillary
LIQUID PHASE: D6-1
FILM THICKNESS:. l.Outn
COLUMN DIMENSIONS: 0.32nm ID,
30 M long

M

_/ '

*

u
©

u
o

rH

JC
V

m

4i

V

•	w>
e o

•	^

u
0 •

•h e

>65
• ¦

«h h
« u

u
o

X

V

r

i



10 15 20
TIME (KEN)

25

30

35

Flqure 2.

Extract of reagent water spiked at 20 ug/L with atrazine,
60 ug/L with slmazine, 0.45 uq/L with cis-nonachlor, and
0.35 ug/L with hexachlorocydopentadlene, heptachlor,
alpha chlordane, gamma chlordane, and trans-nonachlor.

505-24


-------
On
O
On

l>j
On

I



10 la 14 16

10 20 22

TINE (HIN)

Figure 3. Hexane spiked at 11.4 ug/L with Aroclor 1016

COLUMN: Fused silica capillary
LIQUID PHASE: DB-1
FILM THICKNESS: I.OiM
COLUMN DIMENSIONS: 0.32mm 10, 30 M long

* * » ' » » «'	I	I	I	1	L.

24 26 28 SO 32 34 » 38 40 42 44


-------
COLUMN: Fused silica capillary
LIQUID PHASE: 06-1
FILM THICKNESS: 1.0**

COLUMN DIMENSIONS: 0.3&M 10. 30 H long



J	L

14 1 • 18 20 22 24 » 28 90 32 94 3* 96 40 42

TIME (MIN)

ug/L with Aroclor 1221.


-------
COLUMN: Fused silica capillary


-------
COLUMN: Fused silica capillary
IIQUIO PHASE: DB-1
FILM THICKNESS: I.O11M
COLUMN DIMENSIONS: 0.32m 10, 30 N long

c

JfUU

mil

u



10 la 14 16

¦ ¦ '
le 20 22
TIME (MIN)

24

2S 30 32 34

38 40 42

Figure 6. Hexane spiked at 57.1 ug/L with Aroclor 1242.


-------
TIME (MIN)

Figure7. Hex«ne spiked at S7.1 ug/L with ^roclor 1248.


-------
TIME (MIN)

Figure 8. Hexane spiked at 42.9 ug/l with Aroclor 1254.


-------
On
O
On

00

I

JL



JL -

jLif

u

JL

JL

X

2 4 • • IO 11 14 II II N 22 24

TINE (NIN)

Figure 9. Hexane spiked at 34.3 ug/L with Aroclor 1260

COLUMN: Fused silica capillary
LIQUID PHASE: OS-1
FILN THICKNESS: I.Otfi
COLUMN DIMENSIONS: 0.3&M 10. 30 H l«m*


-------
TIME (MIN)

Figure 10. Hexane spiked at 28.6 ug/L with chlordane.


-------
on
O
On

CO
CO

10 ia u k is 20 2a

TIME (NIN)

Figure 11. Hexane spiked at 57.1 ug/L with toxapheoe.

COLUMN: Fused silica capillary
LIQUID PHASE: Ot-1
FILM THICKNESS: l.OwM
COLUMN DIMENSIONS: 0.32m 10. 30 H lonfl


-------