United States
Environmental Protection
Agency
Office of Water
(4601)
EPA814-B-96-006
April 1996
x>EPA
Reprints of EPA Methods for
Chemical Analyses under the
Information Collection Rule
EPA
814
B
96
006
c.2
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[EPA
8 IT
6
16
1000
EPA814-B-96-006
April 1996
REPRINTS OF EPA METHODS FOR
CHEMICAL ANALYSES UNDER THE
INFORMATION COLLECTION RULE
U S. EPA Headquarters Library
Mail code 3201
1200 Pennsylvania Avenue NW
Washington DC 20460
Informr.t!o:i Issources Center
US EFA (3^04r
401 M Street, SW
Washington, DC 20460 '
OFFICE OF WATER
OFFICE OF GROUND WATER AND DRINKING WATER
TECHNICAL SUPPORT DIVISION
CINCINNATI, OHIO 45268
Printed on Recycled Paper
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DISCLAIMER
The methods in this manual have been reviewed and printed previously by
the National Exposure Research Laboratory - Cincinnati, U.S. Environmental
Protection Agency {formerly the Environmental Monitoring Systems Laboratory -
Cincinnati, U.S. Environmental Protection Agency). Mention of trade names or
commercial products does not constitute endorsement or recommendation for use.
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ABSTRACT
This publication, "Reprints of EPA Methods for Chemical Analyses under the
Information Collection Rule," is a compilation of EPA methods cited in §141.142
(b) (1) of the Information Collection Rule. The methods are reprinted from the
original manuals which were published by the National Exposure Research
Laboratory (formerly the Environmental Monitoring Systems Laboratory) -
Cincinnati.
Method 300, "Determination of Inorganic Anions by Ion Chromatography,"
was originally published in "Methods for the Determination of Inorganic Substances
in Environmental Samples, " EPA/600/R-93/100, August 1993, PB94-121811.
Method 350.1, "Determination of Ammonia Nitrogen by Semi-Automated
Colorimetry," was originally published in "Methods for the Determination of
Inorganic Substances in Environmental Samples," EPA/600/R-93/100, August
1993, PB94-121811.
Method 551.1, "Determination of Chlorination Disinfection Byproducts,
Chlorinated Solvents, and Halogenated Pesticides/Herbicides in Drinking Water by
Liquid-Liquid Extraction and Gas Chromatography with Electron-Capture Detection,"
was originally published in "Methods for the Determination of Organic Compounds
in Drinking Water - Supplement III," EPA/600/R-95/131, August 1995,
PB95-261616.
Method 552.1, "Determination of Haloacetic Acids and Dalapon in Drinking
Water by Ion-Exchange Liquid-Solid Extraction and Gas-Chromatography with an
Electron Capture Detector," was originally published in "Methods for the
Determination of Organic Compounds in Drinking Water - Supplement II,"
EPA/600/R-92/129, August 1992, PB92-207703.
Method 552.2, "Determination of Haloacetic Acids and Dalapon in Drinking
Water by Liquid-Liquid Extraction, Derivatization and Gas Chromatography with
Electron Capture Detection," was originally published in "Methods for the
Determination of Organic Compounds in Drinking Water - Supplement III,"
EPA/600/R-95/131, August 1995, PB95-261616.
HI
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TABLE OF CONTENTS
Method
Number
300.0
350.1
551.1
552.1
552.2
Title
Disclaimer
Abstract .
Revision
iii
Determination of Inorganic Anions 2.1
by Ion Chromatography
Determination of Ammonia Nitrogen 2.0
By Semi-Automated Colorimetry
Determination of Chlorination 1.0
Disinfection Byproducts, Chlorinated
Solvents, and Haiogenated Pesticides/
Herbicides in Drinking Water by
Liquid-Liquid Extraction and Gas
Chromatography with Electron-Capture
Detection
Determination of Haloacetic Acids and 1.0
Daiapon in Drinking Water by Ion-
Exchange Liquid-Solid Extraction and
Gas-Chromatography with an Electron
Capture Detector
Determination of Haloacetic Acids and 1.0
Daiapon in Drinking Water by Liquid-
Liquid Extraction, Derivatization and
Gas Chromatography with Electron
Capture Detection
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METHOD 300.0
DETERMINATION OF INORGANIC ANIONS BY ION CHROMATOGRAPHY
John D. Pfaff
Inorganic Chemistry Branch
Chemistry Research Division
Revision 2.1
August 1993
ENVIRONMENTAL MONITORING SYSTEMS LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
300.0-1
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METHOD 300.0
DETERMINATION OF INORGANIC ANIONS BY ION CHRONATOGRAPHY
1.0 SCOPE AND APPLICATION
1.1 This method covers the determination of the following inorganic
anions:
PART A.
Bromide
Chloride
Fluoride
Nitrate
PART B.
Bromate
Chlorate
Nitrite
Ortho-Phosphate-P
Sulfate
Chlorite
1.2 The matrices applicable to each method are shown below:
A. Drinking water, surface water, mixed domestic and industrial
wastewaters, groundwater, reagent waters, solids {after
extraction 11.7), leachates (when no acetic acid is used).
B. Drinking water and reagent waters
1.3 The single laboratory Method Detection Limit (MDL defined in Sect.
3.2) for the above analytes is listed in Tables 1A and IB. The MDL
for a specific matrix may differ from those listed, depending upon
the nature of the sample.
1.4 Method A is recommended for drinking and wastewaters. The
multilaboratory ranges tested for each anion are as follows:
Analvte
Bromide
Chloride
Fluoride
Nitrate-N
Nitrite-N
mq/L
0.63 - 21.0
0.78 - 26.0
0.26 - 8.49
0.42 - 14.0
0.36 - 12.0
Ortho-Phosphate-P 0.69 - 23.1
Sulfate 2.85 - 95.0
300.0-2
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1.5 This method is recommended for use only by or under the supervision
of analysts experienced in the use of ion chromatography and in the
interpretation of the resulting ion chromatograms.
1.6 When this method is used to analyze unfamiliar samples for any of
the above anions, anion identification should be supported by the
use of a fortified sample matrix covering the anions of interest.
The fortification procedure is described in Sect. 11.6.
1.7 Users of the method data should state the data-quality objectives
prior to analysis. Users of the method must demonstrate the ability
to generate acceptable results with this method, using the
procedures described in Sect. 9.0.
2.0 SUMMARY OF METHOD
2.1 A small volume of sample, typically 2 to 3 ml, is introduced into
an ion chromatograph. The anions of interest are separated and
measured, using a system comprised of a guard column, analytical
column, suppressor device, and conductivity detector.
2.2 The main differences between Parts A and B are the separator columns
and guard columns. Sections 6.0 and 7.0 will elicit the
differences.
2.3 An extraction procedure must be performed to use this method for
solids (See 11.7).
2.4 Limited performance-based method modifications may be acceptable
provided they are fully documented and meet or exceed requirements
expressed in Sect. 9.0, Quality Control.
3.0 DEFINITIONS
3.1 CALIBRATION BLANK (CB) — A volume of reagent water fortified with
the same matrix as the calibration standards, but without the
analytes, internal standards, or surrogate analytes.
3.2 CALIBRATION STANDARD (CAL) — A solution prepared from the primary
dilution standard solution or stock standard "'solutions and the
internal standards and surrogate analytes. 'The CAL solutions are
used to calibrate the instrument response with respect to analyte
concentration.
3.3 FIELD DUPLICATES (FD) — 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 field
duplicates indicate the precision associated with sample collection,
preservation and storage, as well as with laboratory procedures.
3.4 INSTRUMENT PERFORMANCE CHECK SOLUTION (IPC) — A solution of one or
more method analytes, surrogates, internal standards, or other test
300.0-3
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substances used to evaluate the performance of the instrument system
with respect to a defined set of criteria.
3.5 LABORATORY FORTIFIED BLANK (LFB) -- An aliquot of reagent water or
other blank matrices 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.
3.6 LABORATORY FORTIFIED SAMPLE MATRIX (LFM) ~ An aliquot of an
environmental 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.
3.7 LABORATORY REAGENT BLANK (LRB) — An aliquot of reagent water or
other blank matrices that are 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.
3.8 LINEAR CALIBRATION RANGE (LCR) — The concentration range over which
the instrument response is linear.
3.9 MATERIAL SAFETY DATA SHEET (MSDS) — Written information provided by
vendors concerning a chemical's toxicity, health hazards, physical
properties, fire, and reactivity data including storage, spill, and
handling precautions.
3.10 METHOD DETECTION LIMIT (MDL) -- The minimum concentration of an
analyte that can be identified, measured and reported with 99%
confidence that the analyte concentration is greater than zero.
3.11 PERFORMANCE EVALUATION SAMPLE (PE) — A solution of method analytes
distributed by the Quality Assurance Research Division (QARD),
Environmental Monitoring Systems Laboratory (EMSL-Cincinnati), U. S.
Environmental Protection Agency, Cincinnati, Ohio, to multiple
laboratories for analysis. A volume of the solution is added to a
known volume of reagent water and analyzed with procedures used for
samples. Results of analyses are used by QARD to determine
statistically the accuracy and precision that can be expected when a
method is performed by a competent analyst. Analyte true values are
unknown to the analyst.
3.12 QUALITY CONTROL SAMPLE (QCS) — A solution of method analytes of
known concentrations that is used to fortify an aliquot of LRB or
300.0-4
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sample matrix. The QCS is obtained from a source external to the
laboratory and different from the source of calibration standards.
It is used to check laboratory performance with externally prepared
test materials.
3.13 STOCK STANDARD SOLUTION (SSS) — A concentrated solution containing
one or more method analytes prepared in the laboratory using assayed
reference materials or purchased from a reputable commercial source.
4.0 INTERFERENCES
4.1 Interferences can be caused by substances with retention times that
are similar to and overlap those of the anion of interest. Large
amounts of an anion can interfere with the peak resolution of an
adjacent anion. Sample dilution and/or fortification can be used to
solve most interference problems associated with retention times.
4.2 The water dip or negative peak that elutes near, and can interfere
with, the fluoride peak can usually be eliminated by the addition of
the equivalent of 1 mL of concentrated eluent (7.3 100X) to 100 mL
of each standard and sample.
4.3 Method interferences may be caused by contaminants in the reagent
water, reagents, glassware, and other sample processing apparatus
that lead to discrete artifacts or elevated baseline in ion
chromatograms.
4.4 Samples that contain particles larger than 0.45 microns and reagent
solutions that contain particles larger than 0.20 microns require
filtration to prevent damage to instrument columns and flow systems.
4.5 Any anion that is not retained by the column or only slightly
retained will elute in the area of fluoride and interfere. Known
coelution is caused by carbonate and other small organic anions. At
concentrations of fluoride above 1.5 mg/L, this interference may not
be significant, however, it is the responsibility of the user to
generate precision and accuracy information in each sample matrix.
4.6 The acetate anion elutes early during the chromatographic run. The
retention times of the anions also seem to differ when large amounts
of acetate are present. Therefore, this method is not recommended
for leachates of solid samples when acetic acid is used for pH
adjustment.
4.7 The quantitation of unretained peaks should be avoided, such as low
molecular weight organic acids (formate, acetate, propionate etc.)
which are conductive and coelute with or near fluoride and would
bias the fluoride quantitation in some drinking and most waste
waters.
4.8 Any residual chlorine dioxide present in the sample will result in
the formation of additional chlorite prior to analysis. If any
300.0-5
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concentration of chlorine dioxide is suspected in the sample purge
the sample with an inert gas (argon or nitrogen) for about five
minutes or until no chlorine dioxide remains.
5.0 SAFETY
5.1 The toxicity or carcinogenicity of each reagent used in this method
have not been fully established. Each chemical should be regarded
as a potential health hazard and exposure should be as low as
reasonably achievable. Cautions are included for known extremely
hazardous materials or procedures.
5.2 Each laboratory is responsible for maintaining a current awareness
file of OSHA regulations regarding the safe handling of the
chemicals specified in this method. A reference file of Material
Safety Data Sheets (MSDS) should be made available to all personnel
involved in the chemical analysis. The preparation of a formal
safety plan is also advisable.
5.3 The following chemicals have the potential to be highly toxic or
hazardous, consult MSDS.
5.3.1 Sulfuric acid (7.4)
6.0 Equipment and Supplies
6.1 Balance — Analytical, capable of accurately weighing to the nearest
0.0001 g.
6.2 Ion chromatograph — Analytical system complete with ion chromato-
graph and all required accessories including syringes, analytical
columns, compressed gasses and detectors.
6.2.1 Anion guard column: A protector of the separator column. If
omitted from the system the retention times will be shorter.
Usually packed with a substrate the same as that in the
• separator column.
6.2.2 Anion separator column: This column produces the separation
shown in Figures 1 and 2.
6.2.2.1 Anion analytical column (Method A): The
separation shown in Figure 1 was generated using a
Dionex AS4A column (P/N 37041). An optional
column may be used if comparable resolution of
peaks is obtained, and the requirements of Sect.
9.2 can be met.
6.2.2.2 Anion analytical column (Method B). The
separation shown in Figure 2 was generated using a
Dionex AS9 column (P/N 42025). An optional column
may be used if comparable resolution of peaks is
300.0-6
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6.2.3
6.2.4
obtained and the requirements of Sect. 9.2 can be
met.
Anion suppressor device: The data presented In this method
were generated using a Dionex anion micro membrane
suppressor (P/N 37106).
Detector ~ Conductivity cell: approximately 1.25 pL
internal volume, (Dionex, or equivalent) capable of
providing data as required in Sect. 9.2.
6.3 The Oionex AI-450 Data Chromatography Software was used to generate
all the data in the attached tables. Systems using a strlpchart
recorder and integrator or other computer based data system may
achieve approximately the same MOL's but the user should demonstrate
this by the procedure outlined in Sect. 9.2.
7.0 Reagents and Standards
7.1 Sample bottles: Glass or polyethylene of sufficient volume to
allow replicate analyses of anions of interest.
7.2 Reagent water: Distilled or deionized water, free of the anions of
interest. Water should contain particles no larger than 0.20
microns.
7.3 Eluent solution (Method A and Method 8): Sodium bicarbonate (CASRN
144-55-8) 1.7 mM, sodium carbonate (CASRN 497-19-8) 1.8 mM.
Dissolve 0.2856 g sodium bicarbonate (NaHC03) and 0.3816 g of sodium
carbonate (Na2C03) in reagent water (7.2) and dilute to 2 L.
7.4 Regeneration solution (micro membrane suppressor): Sulfuric acid
(CASRN-7664-93-9) 0.025N. Dilute 2.8 ml cone, sulfuric acid
(H2S04) to 4 L with reagent water.
7.5 Stock standard solutions, 1000 mg/L (1 mg/ml): Stock standard
solutions may be purchased as certified solutions or prepared from
ACS reagent grade materials (dried at 105°C for 30 min) as listed
below.
7.5.1 Bromide (Br") 1000 mg/L: Dissolve 1.2876 g sodium bromide
(NaBr, CASRN 7647-15-6) in reagent water and dilute to 1 L.
7.5.2 Bromate (Br03") 1000 mg/L: Dissolve 1.1798g of sodium
bromate (NaBrO,, CASRN 7789-38-0) in reagent water and
dilute to 1 L.
7.5.3 Chlorate (CIO,') 1000 mg/L: Dissolve 1.2753g of sodium
chlorate (NaCIO,, CASRN 7775-09-9) in reagent water and
dilute to 1 L.
300.0-7
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7.5.4 Chloride (CL") 1000 mg/L: Dissolve 1.6485 g sodium
chloride (NaCl, CASRN 7647-14-5) in reagent water and
dilute to 1 L.
7.5.5 Chlorite (C102") 1000 mg/L: Dissolve 1.3410g of sodium
chlorite (NaClO,, CASRN 7758-19-2) in reagent water and
dilute to 1 L.
7.5.6 Fluoride (F") 1000 mg/L: Dissolve 2.2100g sodium fluoride
(NaF, CASRN 7681-49-4) in reagent water and dilute to 1 L.
7.5.7 Nitrate (NO",-N) 1000 mg/L: Dissolve 6.0679 g sodium
nitrate (NaN03, CASRN 7631-99-4) in reagent water and
dilute to 1 L.
7.5.8 Nitrite (NO~,-N) 1000 mg/L: Dissolve 4.9257 g sodium
nitrite (NaN02, CASRN 7632-00-0) in reagent water and
dilute to 1 L.
7.5.9 Phosphate (PO=.-P) 1000 mg/L: Dissolve 4.3937 g potassium
phosphate (KH2PO,, CASRN 7778-77-0) in reagent water
and dilute to 1 1.
7.5.10 Sulfate (SO/8) 1000 mg/L: Dissolve 1.8141 g potassium
sulfate (K,S04, CASRN 7778-80-5) in reagent water and
dilute to 1 L.
NOTE: Stability of standards: Stock standards (7.5) are
stable for at least 1 month when stored at 4°C.
Except for the chlorite standard which is only stable
for two weeks. Dilute working standards should be
prepared weekly, except those that contain nitrite
and phosphate should be prepared fresh daily.
7.6 Ethylenediamine preservation solution: Dilute 10 mL of
ethylenediamine (99%) (CASRN 107-15-3) to 200 mL with reagent
water. Use 1 mL of this dilution to each 1 L of sample taken.
8.0 Sample Collection. Preservation and Storage
8.1 Samples should be collected in plastic or glass bottles. All
bottles must be thoroughly cleaned andirinsed with reagent water.
Volume collected should be sufficient to insure a representative
sample, allow for replicate analysis, if required, and minimize
waste disposal.
8.2 Sample preservation and holding times for the anions that can be
determined by this method are as follows:
Analvte
Bromate
Preservation
None required
300.0-8
Holding Time
28 days
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Bromide
Chlorate
Chloride
Chlorite
Fluoride
Nitrate-N
Combined
(Nitrate/Nitrite)
Nitrite-N
0-Phosphate-P
Sulfate
None required
None required
None required
Cool to 4°C
None required
Cool to 4°C
cone. H2SO,.
to a pH •
Cool to 4°C
Cool to 4°C
Cool to 4°C
28 days
28 days
28 days
immediately
28 days
48 hours
28 days
48 hours
48 hours
28 days
NOTE: If the determined value for the combined
nitrate/nitrite exceeds 0.5 mg/L as N", a resample
must be analyzed for the individual concentrations
of nitrate and nitrite.
8.3 The method of preservation and the holding time for samples
analyzed by this method are determined by the anions of interest.
In a given sample, the anion that requires the most preservation
treatment and the shortest holding time will determine the preser-
vation treatment. It is recommended that all samples be cooled to
4°C and held for no longer than 28 days for Method A and analyzed
immediately in Method B.
NOTE: If the sample cannot be analyzed for chlorite within < 10
minutes, the sample may be preserved by adding 1 ml of the
ethylenediamine (EDA) preservation solution (7.6) to 1 L
of sample. This will preserve the concentration of the
chlorite for up to 14 days. This addition of EDA has no
effect on bromate or chlorate, so they can also be
determined in a sample preserved with EDA. Residual
chlorine dioxide should be removed from the sample
(per 4.8) prior to the addition of EDA.
9.0 QUALITY CONTROL
9.1 Each laboratory using this method is required to operate a formal
• quality control (QC) program. The minimum requirements of this
program consist of an initial demonstration of laboratory
capability, and the periodic analysis of laboratory reagent blanks,
fortified blanks and other laboratory solutions as a continuing
check on performance. The laboratory is required to maintain per-
formance records that define the quality of the data that are
generated.
9.2 INITIAL DEMONSTRATION OF PERFORMANCE
9.2.1 The initial demonstration of performance is used to
characterize instrument performance (determination of LCRs
and analysis of QCS) and laboratory performance
300.0-9
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(determination of MDLs) prior to performing analyses by this
method.
9.2.2 Linear Calibration Range (LCR) — The LCR must be determined
initially and verified every 6 months or whenever a
significant change in instrument response is observed or
expected. The initial demonstration of linearity must use
sufficient standards to insure that the resulting curve is
linear. The verification of linearity must use a minimum of
a blank and three standards. If any verification data
exceeds the initial values by ± 10%, linearity must be
reestablished. If any portion of the range is shown to be
nonlinear, sufficient standards must be used to clearly
define the nonlinear portion.
9.2.3 Quality Control Sample (QCS) — When beginning the use of
this method, on a quarterly basis or as required to meet
data-quality needs, verify the calibration standards and
acceptable instrument performance with the preparation and
analyses of a QCS. If the determined concentrations are not
within ± 10% of the stated values, performance of the
determinative step of the method is unacceptable. The
source of the problem must be identified and corrected
before either proceeding with the initial determination of
MDLs or continuing with on-going analyses.
9.2.4 Method Detection Limit (MDL) — MDLs must be established for
all analytes, using reagent water (blank) fortified at a
concentration of two to three times the estimated instrument
detection limit/6' To determine MDL values, take seven
replicate aliquots of the fortified reagent water and
process through the entire analytical method. Perform all
calculations defined in the method and report the
concentration values in the appropriate units. Calculate
the MDL as follows:
MDL = (t) x (S)
where, t = Student's t value for a 99% confidence level
and a standard deviation estimate with n-1
degrees of freedom [t = 3.14 for seven
replicates].
S = standard deviation of the replicate analyses.
MDLs should be determined.every 6 months, when a new
operator begins work or whenever there is a significant
change in the background or instrument response.
9.3 ASSESSING LABORATORY PERFORMANCE
300.0-10
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9.3.1 Laboratory Reagent Blank (LRB) -- The laboratory must
analyze at least one LRB with each batch of samples. Data
produced are used to assess contamination from the
laboratory environment. Values that exceed the MDL indicate
laboratory or reagent contamination should be suspected and
corrective actions must be taken before continuing the
analysis.
9.3.2 Laboratory Fortified Blank (LFB) — The laboratory must
analyze at least one LFB with each batch of samples.
Calculate accuracy as percent recovery (Sect. 9.4.2). If
the recovery of any analyte falls outside the required
control limits of 90-110%, that analyte is judged out of
control, and the source of the problem should be identified
and resolved before continuing analyses.
9.3.3 The laboratory must use LFB analyses data to assess
laboratory performance against the required control limits
of 90-110%. When sufficient internal performance data
become available (usually a minimum of 20-30 analyses),
optional control limits can be developed from the percent
mean recovery (x) and the standard deviation (S) of the mean
recovery. These data can be used to establish the upper and
lower control limits as follows:
UPPER CONTROL LIMIT - x + 3S
LOWER CONTROL LIMIT - x - 3S
The optional control limits must be equal to or better than
the required control limits of 90-110%. After each five to
ten new recovery measurements, new control limits can be
calculated using only the most recent 20-30 data points.
Also, the standard deviation (S) data should be used to
establish an on-going precision statement for the level of
concentrations included in the LFB. These data must be kept
on file and be available for review.
9.3.4 Instrument Performance Check Solution (IPC) — For all
determinations the laboratory must analyze the IPC (a mid-
range check standard) and a calibration blank immediately
following daily calibration, after every tenth sample (or
more frequently, if required) and at the end of the sample
run. Analysis of the IPC solution and calibration blank
immediately following calibration must verify that the
instrument is within ± 10% of calibration. Subsequent
analyses of the IPC solution must verify the calibration is
still within ± 10%. If the calibration cannot be verified
within the specified limits, reanalyze the IPC solution. If
the second analysis of the IPC solution confirms calibration
to be outside the limits, sample analysis must be
discontinued, the cause determined and/or in the case of
drift, the instrument recalibrated. All samples following
300.0-11
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the last acceptable IPC solution must be reanalyzed. The
analysis data of the calibration blank and IPC solution must
be kept on file with the sample analyses data.
9.4 ASSESSING ANALYTE RECOVERY AND DATA QUALITY
9.4.1 Laboratory Fortified Sample Matrix (LFH) -- The laboratory
must add a known amount of analyte to a minimum of 10% of
the routine samples. In each case the LFM aliquot must be a
duplicate of the aliquot used for sample analysis. The
analyte concentration must be high enough to be detected
above the original sample and should not be less than four
times the MDL. The added analyte concentration should be
the same as that used in the laboratory fortified blank.
9.4.1.1 If the concentration of fortification is less than
25% of the background concentration of the matrix
the matrix recovery should not be calculated.
9.4.2 Calculate the percent recovery for each analyte, corrected
for concentrations measured in the unfortified sample, and
compare these values to the designated LFM recovery range
90-110%. Percent recovery may be calculated using the
following equation:
C8-C
x 100
where, R « percent recovery.
C8 * fortified sample concentration.
C - sample background concentration.
s » concentration equivalent of analyte added to
sample.
9.4.3 Until sufficient data becomes available (usually a minimum
of 20 to 30 analysis), assess laboratory performance against
recovery limits for method A of 80 to 120% and 75 to 125%
for method B. When sufficient Internal performance data
becomes available develop control limits from percent mean
recovery and the standard deviation of the mean recovery.
9.4.4 If the recovery of any analyte falls outside the designated
LFM recovery range and the laboratory performance for that
analyte is shown to be in control (Sect. 9.3), the recovery
problem encountered with the LFM is judged to be either
matrix or solution related, not system related.
9.4.5 Where reference materials are available, they should be
analyzed to provide additional performance data. The
300.0-12
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analysis of reference samples is a valuable tool for
demonstrating the ability to perform the method acceptably.
9.4.6 In recognition of the rapid advances occurring in chromatog-
raphy, the analyst is permitted certain options, such as the
use of different columns and/or eluents, 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 Sect. 9.2.
9.4.7 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 in the chromatogram, confirmatory
techniques such as sample dilution and fortification, must
be used. Whenever possible, the laboratory should perform
analysis of quality control check samples and participate in
relevant performance evaluation sample studies.
9.4.8 At least quarterly, replicates of LFBs should be analyzed to
determine the precision of the laboratory measurements. Add
these results to the on-going control charts to document
data quality.
9.4.9 When using Part B, the analyst should be aware of the purity
of the reagents used to prepare standards. Allowances must
be made when the solid materials are less than 99% pure.
10.0 Calibration and Standardization
10.1 Establish ion chromatographic operating parameters equivalent to
those indicated in Tables 1A or IB.
10.2 For each analyte of interest, prepare calibration standards at a
minimum of three concentration levels and a blank by adding
accurately measured volumes of one or more stock standards (7.5) to
a volumetric flask and diluting to volume with reagent water. If
a sample analyte concentration exceeds the calibration range the
sample may be diluted to fall within the range. If this is not
possible then three new calibration concentrations must be chosen,
two of which must bracket the concentration of the sample analyte of
interest. Each attenuation range of the instrument used to analyze
a sample must be calibrated individually.
10.3 Using injections of 0.1 to 1.0 ml (determined by injection loop
volume) of each calibration standard, tabulate peak height or area
responses against the concentration. The results are used to
prepare a calibration curve for each analyte. During this pro-
cedure, retention times must be recorded.
300.0-13
-------
10.4 The calibration curve must be verified on each working day, or
whenever the anion eluent is changed, and after every 20
samples. If the response or retention time for any analyte varies
from the expected values by more than ± 10%, the test must be
repeated, using fresh calibration standards. If the results are
still more than ± 10%, a new calibration curve must be prepared
for that analyte.
10.5 Nonlinear response can result when the separator column capacity is
exceeded (overloading). The response of the detector to the sample
when diluted 1:1, and when not diluted, should be compared. If the
calculated responses are the same, samples of this total anionic
concentration need not be diluted.
11.0 Procedure
11.1 Tables 1A and IB summarize the recommended operating conditions for
the ion chromatograph. Included in these tables are estimated
retention times that can be achieved by this method. Other columns,
chromatographic conditions, or detectors may be used if the
requirements of Sect. 9.2 are met.
11.2 Check system calibration daily and, if required, recalibrate as
described in Sect. 10.
11.3 Load and inject a fixed amount of well mixed sample. Flush
injection loop thoroughly, using each new sample. Use the same size
loop for standards and samples. Record the resulting peak size in
area or peak height units. An automated constant volume injection
system may also be used.
11.4 The width of the retention time window used to make identifications
should be based upon measurements of actual retention time varia-
tions 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 each analyte. However, the experience of
the analyst should weigh heavily in the interpretation of
chromatograms.
11.5 If the response for the peak exceeds the working range of the
system, dilute the sample with an appropriate amount of reagent
water and reanalyze.
11.6 If the resulting chromatogram fails to produce adequate resolution,
or if identification of specific anions is questionable, fortify the
sample with an appropriate amount of standard and reanalyze.
MOTE: Retention time is inversely proportional to concentration.
Nitrate and sulfate exhibit the greatest amount of change,
although all anions are affected to some degree. In some
cases this peak migration may produce poor resolution or
identification.
300.0-14
-------
11.7 The following extraction should be used for solid materials. Add an
amount of reagent water equal to ten times the weight of dry solid
material taken as a sample. This slurry is mixed for ten minutes
using a magnetic stirring device. Filter the resulting slurry
before injecting using a 0.45 n membrane type filter. This can be
the type that attaches directly to the end of the syringe. Care
should be taken to show that good recovery and identification of
peaks is obtained with the user's matrix through the use of
fortified samples.
11.8 It has been reported that lower detection limits for bromate
(=7 pg/L) can be obtained using a borate based eluent. The use
of this eluent or other eluents that improve method performance may
be considered as a minor modification of the method and as such
still are acceptable.
11.9 Should more complete resolution be needed between peaks the eluent
(7.3) can be diluted. This will spread out the run but will also
cause the later eluting anions to be retained longer. The analyst
must determine to what extent the eluent is diluted. This dilution
should not be considered a deviation from the method.
12.0 DATA ANALYSIS AND CALCULATIONS
12.1 Prepare a calibration curve for each analyte by plotting instrument
response against standard concentration. Compute sample
concentration by comparing sample response with the standard curve.
Multiply answer by appropriate dilution factor.
12.2 Report only those values that fall between the lowest and the
highest calibration standards. Samples exceeding the highest
standard should be diluted and reanalyzed.
12.3 Report results in mg/L.
12.4 Report
NO ' as N
NO, as N
HP04= as P
13.0 METHODS PERFORMANCE
13.1 Tables 1A and 2A give the single laboratory (EMSL-Cincinnati) MDL
for each anion included in the method under the conditions listed.
13.2 Tables 2A and 2B give the single laboratory (EMSL-Cincinnati)
standard deviation for each anion included in the method in a
variety of waters for the listed conditions.
13.3 Multiple laboratory accuracy and bias data (S.) and estimated single
operator values (S ) for reagent, drinking and waste water using
300.0-15
-------
method A are given for each anion in Tables 3 through 9. Data from
19 laboratories were used for this data.
13.4 Some of the bias statements, for example chloride and sulfate, may
be misleading due to spiking small increments of the anion into
large naturally occurring concentrations of the same anion.
14.0 POLLUTION PREVENTION
14.1 Pollution prevention encompasses any technique that reduces or
eliminates the quantity or toxicity of waste at the point of
generation. Numerous opportunities for pollution prevention exist
in laboratory operation. The EPA has established a preferred
hierarchy of environmental management techniques that places
pollution prevention as the management option of first choice.
Whenever feasible, laboratory personnel should use pollution
prevention techniques to address their waste generation. When
wastes cannot be feasibly reduced at the source, the Agency
recommends recycling as the next best option.
14.2 Quantity of the chemicals purchased should be based on expected
usage during its shelf life and disposal cost of unused material.
Actual reagent preparation volumes should reflect anticipated usage
and reagent stability.
14.3 For information about pollution prevention that may be applicable to
laboratories and research institutions, consult "Less is Better:
Laboratory Chemical Management for Waste Reduction," available from
the American Chemical Society's Department of Government
Regulations and Science Policy, 1155 16th Street N.W., Washington
D.C. 20036, (202) 872-4477.
15.0 WASTE MANAGEMENT
15.1 The Environmental Protection Agency requires that laboratory waste
management practices be conducted consistent with all applicable
rules and regulations. Excess reagents, samples and method
process wastes should be characterized and disposed of in an
acceptable manner. The Agency urges laboratories to protect the
air, water, and land by minimizing and controlling all releases from
hoods and bench operations, complying with the letter and spirit of
any waste discharge permit and regulations, and by complying with
all solid and hazardous waste regulations, particularly the
hazardous waste identification rules and land disposal
restrictions. For further information on waste management consult
the "Waste Management Manual for Laboratory Personnel," available
from the American Chemical Society at the address listed in Sect.
14.3.
300.0-16
-------
16.0 REFERENCES
1.
5.
6.
7.
"Determination of Inorganic Disinfection By-Products by Ion
Chromatography", J. Pfaff, C. Brockhoff. J. Am. Water Works Assoc.,
Vol 82, No. 4, pg 192.
Standard Methods for the Examination of Water and Wastewater,
Method 4110B, "Anions by Ion Chromatography11, 18th Edition of
Standard Methods (1992).
Dionex, System 4000 Operation and Maintenance Manual, Dionex
Corp., Sunnyvale, California 94086, 1988.
Method Detection Limit (MDL) as described in "Trace Analyses for
Wastewater,11 J. Glaser, D. Foerst, G. McKee, S. Quave, W. Budde,
Environmental Science and Technology, Vol. 15, Number 12, page
1426, December, 1981.
American Society for Testing and Materials. Test Method for Anions
in Water by Chemically-Suppressed Ion Chromatography D4327-91.
Annual Book of Standards, Vol 11.01 (1993).
Code of Federal Regulations 40, Ch. 1, Pt. 136, Appendix B.
Hautman, D.P. & Bolyard, M. Analysis of Oxyhalide Disinfection By-
products and other Anions of Interest in Drinking Water by Ion
Chromatography. Jour, of Chromatog., 602, (1992), 65-74.
300.0-17
-------
17.0 TABLES. DIAGRAMS. FLOWCHARTS AND VALIDATION DATA
TABLE 1A. CHROMATOGRAPHIC CONDITIONS AND DETECTION LIMITS
IN REAGENT WATER (PART A)
* RETENTION
ANALYTE
PEAK f
TIME(HIN)
MDL
mg/L
Fluoride 1 1.2
Chloride 2 1.7
Nitrite-N 3 2.0
Bromide 4 2.9
Nitrate-N 5 3.2
o-Phosphate-P 6 5.4
Sulfate 7 6.9
0.01
0.02
0.004
0.01
0.002
0.003
0.02
Standard Conditions:
Columns: as specified in 6.2.2.1
Detector: as specified in 6.2.4
Eluent: as specified in 7.3
Pump Rate: 2.0 mL/min.
Sample Loop: 50 juL
MDL calculated from data system using a y-axis selection of
1000 ns and with a stripchart recorder with an attenuator
setting of 1 uMHO full scale.
* See Figure 1
300.0-18
-------
TABLE IB. CHROMATOGRAPHIC CONDITIONS AND DETECTION LIMITS
IN REAGENT WATER (PART B)
RETENTION
ANALYTE
PEAK #
TIME(MIN)
NDL
mg/L
Chlorite
Bromate
Chlorate
1
2
4
2.8
3.2
7.1
0.01
0.02
0.003
Standard Conditions:
Column: as specified in 6.2.2.2
Detector: as specified in 6.2.4
Eluent: as specified in 7.3
* See Figure 2
Pump Rate: 1.0 mL/min.
Sample Loop: 50 fil
Attentuation - 1
y-axis - 500 ns
300.0-19
-------
TABLE 2A. SINGLE-OPERATOR ACCURACY AND BIAS OF STANDARD ANIONS
(METHOD A)
ANALYTE
Bromide
Chloride
Fluoride
Nitrate- N
Nitrite- N
o-Phosphate- P
SAMPLE
TYPE
RW
DW
SW
WW
GW
SD
RW
DW
SW
WW
GW
SD
RW
DW
SW
WW
GW
SD
RW
DW
SW
WW
GW
SD
RW
DW
SW
WW
GW
SD
RW
DW
SW
WW
GW
KNOWN NUMBER MEAN STANDAR
CONC. OF RECOVERY DEVI ATI
fma/L) REPLICATES % (ma/Li
5.0
5.0
5.0
5.0
5.0
2.0
20.0
20.0
10.0
20.0
20.0
20.0
2.0
1.0
1.0
1.0
0.4
5.0
10.0
10.0
10.0
10.0
10. 0
10.0
10.0
10.0
5.0
5.0
10.0
2.0
10.0
10.0
10.0
10.0
10.0
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
99
105
95
105
92
82
96
108
86
101
114
90
91
92
73
87
95
101
103
104
93
101
97
82
97
121
92
91
96
98
99
99
98
106
95
0.08
0.10
0.13
0.34
0.34
0.06
0.35
1.19
0.33
5.2
1.3
0.32
0.05
0.06
0.05
0.07
0.07
0.35
0.21
0.27
0.17
0.82
0.47
0.28
0.14
0.25
0.14
0.50
0.35
0.08
0.17
0.26
0.22
0.85
0.33
300.0-20
-------
TABLE 2A (CONT'D)
Sulfate RW
DM
SW
ww
GW
RW = Reagent Water
DW = Drinking Water
SW = Surface Water
20.0
50.0
40.0
40.0
40.0
7
7
7
7
7
99
105
95
102
112
0.40
3.35
1.7
6.4
3.2
WW - Mixed Domestic and Industrial Wastewater
GW = Groundwater
SD = USEPA QC Solid (shale)
300.0-21
-------
TABLE 2B. SINGLE-OPERATOR ACCURACY AND BIAS OF BY-PRODUCT
(PART B)
NUMBER MEAN STANDARD
SAMPLE SPIKE OF RECOVERY DEVIATION
ANALYTE TYPE (mg/L) REPLICATES % (rog/L)
Bromate RW 5.0
1.0
0.1
0.05
DW 5.0
1.0
0.1
0.05
Chlorate RW 5.0
1.0
0.1
0.05
DW 5.0
1.0
0.1
0.05
Chlorite RW 5.0
1.0
0.1
0.05
DW 5.0
1.0
0.1
0.05
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
7
103
98
155
122
95
85
98
98
101
97
100
119
101
115
121
110
100
98
86
94
96
100
76
96
0.07
0.04
0.005
0.01
0.04
0.02
0.005
0.005
0.06
0.01
0.01
0.05
0.04
0.01
0.005
0.01
0.04
0.01
0.01
0.01
0.03
0.02
0.00
0.01
RW = Reagent Water
DW = Drinking Water
300.0-22
-------
TABLE 3. MULTIPLE LABORATORY (n*19)
DETERMINATION OF BIAS FOR FLUORIDE
WATER
Reagent
Drinking
Waste
AM'T ADDED
mg/L
0.26
0.34
2.12
2.55
6.79
8.49
0.26
0.34
2.12
2.55
6.79
8.49
0.26
0.34
2.12
2.55
6.79
8.49
AM'T FOUND
mg/L
0.25
0.29
2.12
2.48
6.76
8.46
0.24
0.34
2.09
2.55
6.84
8.37
0.25
0.32
2.13
2.48
6.65
8.27
st
0.08
0.11
0.07
0.14
0.20
0.30
0.08
0.11
0.18
0.16
0.54
0.75
0.15
0.08
0.22
0.16
0.41
0.36
S0
0.11
0.12
0.19
0.05
0.06
0.25
0.06
0.15
0.20
BIAS
%
-3.8
-14.7
0.0
-2.7
-0.4
-0.4
-7.7
0.0
-1.4
0.0
+0.7
-1.4
-3.8
-5.9
+0.5
-2.7
-2.1
-2.6
300.0-23
-------
TABLE 4. MULTIPLE LABORATORY (n=19)
DETERMINATION OF BIAS FOR CHLORIDE
WATER
Reagent
Drinking
Waste
AM'T ADDED
mg/L
0.78
1.04
6.50
7.80
20.8
26.0
0.78
1.04
6.50
7.80
20.8
26.0
0.78
1.04
6.50
7.80
20.8
26.0
AM'T FOUND
mg/L
0.79
1.12
6.31
7.76
20.7
25.9
0.54
0.51
5.24
6.02
20.0
24.0
0.43
0.65
4.59
5.45
18.3
23.0
st
0.17
0.46
0.27
0.39
0.54
0.58
0.35
0.38
1.35
1.90
2.26
2.65
0.32
0.48
1.82
2.02
2.41
2.50
So
0.29
0.14
0.62
0.20
1.48
1.14
0.39
0.83
1.57
BIAS
%
+1.3
+7.7
-2.9
-0.5
-0.5
-0.4
-30.8
-51.0
-19.4
-22.8
-3.8
-7.7
-44.9
-37.5
-29.4
-30.1
-11.8
-11.5
300.0-24
-------
TABLE 5. MULTIPLE LABORATORY (n=19)
DETERMINATION OF BIAS FOR NITRITE - NITROGEN
HATER
Reagent
Drinking
Waste
AM'T ADDED
mg/L
0.36
0.48
3.00
3.60
9.60
12.0
0.36
0.48
3.00
3.60
9.60
12.0
0.36
0.48
3.00
3.60
9.60
12.0
AM'T FOUND
mg/L
0.37
0.48
3.18
3.83
9.84
12.1
0.30
0.40
3.02
3.62
9.59
11.6
0.34
0.46
3.18
3.76
9.74
12.0
st
0.04
0.06
0.12
0.12
0.36
0.27
0.13
0.14
0.23
0.22
0.44
0.59
0.06
0.07
0.13
0.18
0.49
0.56
So
0.04
0.06
0.26
0.03
0.12
0.28
0.04
0.10
0.26
BIAS
%
+2.8
0.0
+6.0
+6.4
+2.5
+0.6
-16.7
-16.7
+0.7
+0.6
-0.1
-3.1
-5.6
-4.2
+6.0
+4.4
+1.5
+0.3
300.0-25
-------
TABLE 6. MULTIPLE LABORATORY (n*19)
DETERMINATION OF BIAS FOR BROMIDE
WATER
Reagent
Drinking
Waste
AM'T ADDED
mg/L
0.63
0.84
5.24
6.29
16.8
21.0
0.63
0.84
5.24
6.29
16.8
21.0
0.63
0.84
5.24
6.29
16.8
21.0
AM'T FOUND
mg/L
0.69
0.85
5.21
6.17
17.1
21.3
0.63
0.81
5.11
6.18
17.0
20.9
0.63
0.85
5.23
6.27
16.6
21.1
«t
0.11
0.12
0.22
0.35
0.70
0.93
0.13
0.13
0.23
0.30
0.55
0.65
0.15
0.15
0.36
0.46
0.69
0.63
S0
0.05
0.21
0.36
0.04
0.13
0.57
0.09
0.11
0.43
BIAS
%
+9.5
+1.2
-0.6
-1.9
+1.6
+1.5
0.0
-3.6
-2.5
-1.7
+0.9
-0.4
0.0
+1.2
-0.2
-0.3
-1.0
+0.3
300.0-26
-------
TABLE 7. MULTIPLE LABORATORY (n=19)
DETERMINATION OF BIAS FOR NITRATE - NITROGEN
HATER
Reagent
Drinking
Waste
AM'T ADDED
mg/L
0.42
0.56
3.51
4.21
11.2
14.0
0.42
0.56
3.51
4.21
11.2
14.0
0.42
0.56
3.51
4.21
11.2
14.0
AM'T FOUND
mg/L
0.42
0.56
3.34
4.05
11.1
14.4
0.46
0.58
3.45
4.21
11.5
14.2
0.36
0.40
3.19
3.84
10.9
14.1
«t
0.04
0.06
0.15
0.28
0.47
0.61
0.08
0.09
0.27
0.38
0.50
0.70
0.07
0.16
0.31
0.28
0.35
0.74
S0
0.02
0.08
0.34
0.03
0.10
0.48
0.06
0.07
0.51
BIAS
%
0.0
0.0
-4.8
-3.8
-1.1
+2.6
+9.5
+3.6
-1.7
0.0
+2.3
+1.6
-14.6
-28.6
-9.1
-8.8
-3.0
+0.4
300.0-27
-------
TABLE 8. MULTIPLE LABORATORY (n=19)
DETERMINATION OF BIAS FOR ORTHO-PHOSPHATE
WATER
Reagent
Drinking
Waste
AM'T ADDED
mg/L
0.69
0.92
5.77
6.92
18.4
23.1
0.69
0.92
5.77
6.92
18.4
23.1
0.68
0.92
5.77
6.92
18.4
23.1
AM'T FOUND
mg/L
0.69
0.98
5.72
6.78
18.8
23.2
0.70
0.96
5.43
6.29
18.0
22.6
0.64
0.82
5.18
6.24
17.6
22.4
«t
0.06
0.15
0.36
0.42
1.04
0.35
0.17
0.20
0.52
0.72
0.68
1.07
0.26
0.28
0.66
0.74
2.08
0.87
S0
0.06
0.18
0.63
0.17
0.40
0.59
0.09
0.34
1.27
BIAS
'/.
0.0
+6.5
-0.9
-2.0
+2.1
+0.4
+1.4
+4.3
-5.9
-9.1
-2.2
-2.0
-7.2
-10.9
-10.2
-9.8
-4.1
-3.0
300.0-28
-------
TABLE 9. MULTIPLE LABORATORY (n*19)
DETERMINATION OF BIAS FOR SULFATE
WATER
Reagent
Drinking
Waste
AN'T ADDED
mg/L
2.85
3.80
23.8
28.5
76.0
95.0
2.85
3.80
23.8
28.5
76.0
95.0
2.85
3.80
23.8
28.5
76.0
95.0
AN'T FOUND
mg/L
2,83
3.83
24.0
28.5
76.8
95.7
1.12
2.26
21.8
25.9
74.5
92.3
1.89
2.10
20.3
24.5
71.4
90.3
st
0.32
0.92
1.67
1.56
3.42
3.59
0.37
0.97
1.26
2.48
4.63
5.19
0.37
1.25
3.19
3.24
5.65
6.80
So
0.52
0.68
2.33
0.41
0.51
2.70
0.24
0.58
3.39
BIAS
%
-0.7
+0.8
+0.8
-0.1
+1.1
+0.7
-60.7
-40.3
-8.4
-9.1
-2.0
-2.8
-33.7
-44.7
-14.7
-14.0
-6.1
-5.0
300.0-29
-------
Method A
Peak Ret. Time
1 1.17
2 1.73
3 2.02
2 4 2.95
1
I
5 3.20
6 5.38
7 6.92
7
5 A
I
i
Hi i V
JV ,J Y S^ J \^
I I II i
0 2 46 8
Minutes
Figure 1. Chromatogram showing separation using the AS4A column
Ion
F-
ci-
N02-
Br
NO,-
HPO^
so4J-
mg/L
2
20
2
2
10
2
60
Method B
Peak
1
2
3
4
Ret. Time
2.75
3.23
3.63
7.08
Ion
CI02-
Br03-
ci-
CI03-
I
0246
Minutes
Figure 2. Chromatogram showing separation using the ASS column
mg/L
0.1
0.1
0.1
0.1
300.0-30
-------
METHOD 350.1
DETERMINATION OF AMMONIA NITROGEN BY SENI-AUTOMATED COLORIHETRY
Edited by James W. O'Dell
Inorganic Chemistry Branch
Chemistry Research Division
Revision 2.0
August 1993
ENVIRONMENTAL MONITORING SYSTEMS LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
350.1-1
-------
METHOD 350.1
DETERMINATION OF AMMONIA NITROGEN BY SEMI-AUTOMATED COLORIMETRY
1.0 SCOPE AND APPLICATION
1.1 This method covers the determination of ammonia in drinking, ground,
surface, and saline waters, domestic and industrial wastes.
1.2 The applicable range is 0.01 to 2.0 mg/L NH3 as N. Higher
concentrations can be determined by sample dilution. Approximately
60 samples per hour can be analyzed.
1.3 This method is described for macro glassware; however, micro
distillation equipment may also be used.
2.0 SUMMARY OF METHOD
2.1 The sample is buffered at a pH of 9.5 with a borate buffer in order
to decrease hydrolysis of cyanates and organic nitrogen compounds,
and is distilled into a solution of boric acid. Alkaline phenol and
hypochlorite react with ammonia to form indophenol blue that is
proportional to the ammonia concentration. The blue color formed is
intensified with sodium nitroprusside and measured col orimetrically.
2.3 Reduced volume versions of this method that use the same reagents
and molar ratios are acceptable provided they meet the quality
control and performance requirements stated in the method.
2.4 Limited performance-based method modifications may be acceptable
provided they are fully documented and meet or exceed requirements
expressed in Sect. 9.0, Quality Control.
3.0 DEFINITIONS
3.1 CALIBRATION BLANK (CB) — A volume of reagent water fortified with
the same matrix as the calibration standards, but without the
analytes, internal standards, or surrogate analytes.
3.2 CALIBRATION STANDARD (CAL) -- A solution prepared from the primary
dilution standard solution or stock standard solutions and the
internal standards and surrogate analytes. The CAL solutions are
used to calibrate the instrument response with respect to analyte
concentration.
3.3 INSTRUMENT PERFORMANCE CHECK SOLUTION (IPC) — A solution of one or
more method analytes, surrogates, internal standards, or other test
substances used to evaluate the performance of the instrument system
with respect to a defined set of criteria.
350.1-2
-------
3.4 LABORATORY FORTIFIED BLANK (LFB) — An aliquot of reagent water or
other blank matrices 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.
3.5 LABORATORY FORTIFIED SAMPLE MATRIX (LFM) — An aliquot of an
environmental 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.
3.6 LABORATORY REAGENT BLANK (LRB) — An aliquot of reagent water or
other blank matrices that are 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.
3.7 LINEAR CALIBRATION RANGE (LCR) — The concentration range over which
the instrument response is linear.
3.8 MATERIAL SAFETY DATA SHEET (HSDS) - Written information provided by
vendors concerning a chemical's toxicity, health hazards, physical
properties, fire, and reactivity data including storage, spill, and
handling precautions.
3.9 METHOD DETECTION LIMIT (MDL) — The minimum concentration of an
analyte that can be identified, measured and reported with 99%
confidence that the analyte concentration is greater than zero.
3.10 QUALITY CONTROL SAMPLE (QCS) — A solution of method analytes of
known concentrations that is used to fortify an aliquot of LRB or
sample matrix. The QCS is obtained from a source external to the
laboratory and different from the source of calibration standards.
It is used to check laboratory performance with externally prepared
test materials.
3.11 STOCK STANDARD SOLUTION (SSS) ~ A concentrated solution containing
one or more method analytes prepared in the laboratory using assayed
reference materials or purchased from a reputable commercial source.
350.1-3
-------
4.0 INTERFERENCES
4.1 Cyanate, which may be encountered in certain industrial effluents,
will hydrolyze to some extent even at the pH of 9.5 at which
distillation is carried out.
4.2 Residual chorine must be removed by pretreatment of the sample with
sodium thiosulfate or other reagents before distillation.
4.3 Method interferences may be caused by contaminants in the reagent
water, reagents, glassware, and other sample processing apparatus
that bias analyte response.
5.0 SAFETY
5.1 The toxicity or carcinogenicity of each reagent used in this method
have not been fully established. Each chemical should be regarded
as a potential health hazard and exposure should be as low as
reasonably achievable. Cautions are included for known extremely
hazardous materials or procedures.
5.2 Each laboratory is responsible for maintaining a current awareness
file of OSHA regulations regarding the safe handling of the
chemicals specified in this method. A reference file of Material
Safety Data Sheets (MSDS) should be made available to all personnel
involved in the chemical analysis. The preparation of a formal
safety plan is also advisable.
5.3 The following chemicals have the potential to be highly toxic or
hazardous, consult MSDS.
5.3.1 Sulfuric acid (7.6)
5.3.2 Phenol (7.7)
5.3.3 Sodium nitroprusside (7.10)
6.0 EQUIPMENT AND SUPPLIES
6.1 Balance - Analytical, capable of accurately weighing to the nearest
0.0001 g.
6.2 Glassware - Class A volumetric flasks and pi pets as required.
6.3 An all-glass distilling apparatus with an 800-1000-mL flask.
6.4 Automated continuous flow analysis equipment designed to deliver and
react sample and reagents in the required order and ratios.
6.4.1 Sampling device (sampler)
6.4.2 Multichannel pump
350.1-4
-------
6.4.3 Reaction unit or manifold
6.4.4 Colorimetric detector
6.4.5 Data recording device
7.0 REAGENTS AND STANDARDS
7.1 Reagent water - Ammonia free: Such water is best prepared by
passage through an ion exchange column containing a strongly acidic
cation exchange resin mixed with a strongly basic anion exchange
resin. Regeneration of the column should be carried out according
to the manufacturer's instructions.
NOTE 1: All solutions must be made with ammonia-free water.
7.2 Boric acid solution (20 g/L): Dissolve 20 g H3B03 (CASRN 10043-35-
3) in reagent water and dilute to 1 L.
7.3 Borate buffer: Add 88 ml of 0.1 N NaOH (CASRN 1310-73-2) solution
to 500 ml of 0.025 M sodium tetraborate solution (5.0 g anhydrous
Na2B40, [CASRN 1330-43-4] or 9.5 g Na2B40/10H20 [CASRN 1303-96-4] per
L) ana dilute to 1 L with reagent water.
7.4 Sodium hydroxide, 1 N: Dissolve 40 g NaOH in reagent water and
dilute to 1 L.
7.5 Dechlorinating reagents: A number of dechlorinating reagents may be
used to remove residual chlorine prior to distillation. These
include:
7.5.1 Sodium thiosulfate: Dissolve 3.5 g Na2S,03'5H20 (CASRN
10102-17-7) in reagent water and dilute to 1 L. One mi. of
this solution will remove 1 mg/L of residual chlorine in 500
mL of sample.
7.5.2 Sodium sulfite: Dissolve 0.9 g Na2S03 (CASRN 7757-83-7) in
reagent water and dilute to 1 L. One ml removes 1 mg/L Cl
per 500 mL of sample.
7.6 Sulfuric acid 5 N: Air scrubber solution. Carefully add 139 mL of
cone, sulfuric acid (CASRN 7664-93-9) to approximately 500 mL of
reagent water. Cool to room temperature and dilute to 1 L with
reagent water.
7.7 Sodium phenolate: Using a 1-L Erlenmeyer flask, dissolve 83 g
phenol (CASRN 108-95-2) in 500 mL of distilled water. In small
increments, cautiously add with agitation, 32 g of NaOH.
Periodically cool flask under water faucet. When cool, dilute to
1 L with reagent water.
350.1-5
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7.8 Sodium hypochlorite solution: Dilute 250 ml of a bleach solution
containing 5.25% NaOCl (CASRN 7681-52-9) (such as "Clorox") to 500
ml with reagent water. Available chlorine level should approximate
2% to 3%. Since "Clorox" is a proprietary product, its formulation
is subject to change. The analyst must remain alert to detecting
any variation in this product significant to its use in this
procedure. Due to the instability of this product, storage over an
extended period should be avoided.
7.9 Disodium ethylenediamine-tetraacetate (EDTA) (5%): Dissolve 50 g of
EDTA (disodium salt) (CASRN 6381-92-6) and approximately six pellets
of NaOH in 1 L of reagent water.
7.10 Sodium nitroprusside (0.05%): Dissolve 0.5 g of sodium
nitroprusside (CASRN 14402-89-2) in 1 L of reagent water.
7.11 Stock solution: Dissolve 3.819 g of anhydrous ammonium chloride,
NH4C1 (CASRN 12125-02-9), dried at 105°C, in reagent water, and
dilute to 1 L. 1.0 ml = 1.0 mg NH3-N.
7.12 Standard Solution A: Dilute 10.0 ml of stock solution (7.11) to 1 L
with reagent water. 1.0 ml = 0.01 mg NH3-N.
7.13 Standard Solution B: Dilute 10.0 ml of standard solution A (7.12)
to 100.0 ml with reagent water. 1.0 mL = 0.001 mg NH3-N.
8.0 SAMPLE COLLECTION. PRESERVATION AND STORAGE
8.1 Samples should be collected in plastic or glass bottles. All
bottles must be thoroughly cleaned and rinsed with reagent water.
Volume collected should be sufficient to insure a representative
sample, allow for replicate analysis (if required), and minimize
waste disposal.
8.2 Samples must be preserved with H2S04 to a pH < 2 and cooled to 4°C
at the time of collection.
8.3 Samples should be analyzed as soon as possible after collection. If
storage is required, preserved samples are maintained at 4"C and may
be held for up to 28 days.
9.0 QUALITY CONTROL
9.1 Each laboratory using this method is required to operate a formal
quality control (QC) program. The minimum requirements of this
program consist of an initial demonstration of laboratory
capability, and the periodic analysis of laboratory reagent blanks,
fortified blanks and other laboratory solutions as a continuing
check on performance. The laboratory is required to maintain per-
formance records that define the quality of the data that are
generated.
350.1-6
-------
9.2 INITIAL DEMONSTRATION OF PERFORMANCE
9.2.1 The initial demonstration of performance is used to
characterize instrument performance (determination of LCRs
and analysis of QCS) and laboratory performance
(determination of MDLs) prior to performing analyses by this
method.
9.2.2 Linear Calibration Range (LCR) — The LCR must be determined
initially and verified every 6 months or whenever a
significant change in instrument response is observed or
expected. The initial demonstration of linearity must use
sufficient standards to insure that the resulting curve is
linear. The verification of linearity must use a minimum of
a blank and three standards. If any verification data
exceeds the initial values by ± 10%, linearity must be
reestablished. If any portion of the range is shown to be
nonlinear, sufficient standards must be used to clearly
define the nonlinear portion.
9.2.3 Quality Control Sample (QCS) — When beginning the use of
this method, on a quarterly basis or as required to meet
data-quality needs, verify the calibration standards and
acceptable instrument performance with the preparation and
analyses of a QCS. If the determined concentrations are not
within ± 10% of the stated values, performance of the
determinative step of the method is unacceptable. The
source of the problem must be identified and corrected
before either proceeding with the initial determination of
MDLs or continuing with on-going analyses.
9.2.4 Method Detection Limit (MDL) — MDLs must be established for
all analytes, using reagent water (blank) fortified at a
concentration of two to three times the estimated instrument
detection limit.' * To determine MDL values, take seven
replicate aliquots of the fortified reagent water and
process through the entire analytical method. Perform all
calculations defined in the method and report the
concentration values in the appropriate units. Calculate
the MDL as follows:
MDL = (t) x (S)
where, t = Student's t value for a 99% confidence level
and a standard deviation estimate with n-1
degrees of freedom [t = 3.14 for seven
replicates],
S = standard deviation of the replicate analyses.
350.1-7
-------
MDLs should be determined every 6 months, when a new
operator begins work or whenever there is a significant
change in the background or instrument response.
9.3 ASSESSING LABORATORY PERFORMANCE
9.3.1 Laboratory Reagent Blank (LRB) -- The laboratory must
analyze at least one LRB with each batch of samples. Data
produced are used to assess contamination from the
laboratory environment. Values that exceed the MDL indicate
laboratory or reagent contamination should be suspected and
corrective actions must be taken before continuing the
analysis.
9.3.2 Laboratory Fortified Blank (LFB) — The laboratory must
analyze at least one LFB with each batch of samples.
Calculate accuracy as percent recovery (Sect. 9.4.2). If
the recovery of any analyte falls outside the required
control limits of 90-110%, that analyte is judged out of
control, and the source of the problem should be identified
and resolved before continuing analyses.
9.3.3 The laboratory must use LFB analyses data to assess
laboratory performance against the required control limits
of 90-110%. When sufficient internal performance data
become available (usually a minimum of 20-30 analyses),
optional control limits can be developed from the percent
mean recovery (x) and the standard deviation (S) of the mean
recovery. These data can be used to establish the upper and
lower control limits as follows:
UPPER CONTROL LIMIT = x + 3S
LOWER CONTROL LIMIT = x - 3S
The optional control limits must be equal to or better than
the required control limits of 90-110%. After each five to
ten new recovery measurements, new control limits can be
calculated using only the most recent 20-30 data points.
Also, the standard deviation (S) data should be used to
established an on-going precision statement for the level of
concentrations included in the LFB. These data must be kept
on file and be available for review.
9.3.4 Instrument Performance Check Solution (IPC) — For all
determinations the laboratory must analyze the IPC (a mid-
range check standard) and a calibration blank immediately
following daily calibration, after every tenth sample (or
more frequently, if required) and at the end of the sample
run. Analysis of the IPC solution and calibration blank
immediately following calibration must verify that the
instrument is within ± 10% of calibration. Subsequent
analyses of the IPC solution must verify the calibration is
350.1-8
-------
still within ± 10%. If the calibration cannot be verified
within the specified limits, reanalyze the IPC solution. If
the second analysis of the IPC solution confirms calibration
to be outside the limits, sample analysis must be
discontinued, the cause determined and/or in the case of
drift, the instrument recalibrated. All samples following
the last acceptable IPC solution must be reanalyzed. The
analysis data of the calibration blank and IPC solution must
be kept on file with the sample analyses data.
9.4 ASSESSING ANALYTE RECOVERY AND DATA QUALITY
9.4.1 Laboratory Fortified Sample Matrix (LFM) — The laboratory
must add a known amount of analyte to a minimum of 10% of
the routine samples. In each case the LFM aliquot must be a
duplicate of the aliquot used for sample analysis. The
analyte concentration must be high enough to be detected
above the original sample and should not be less than four
times the MDL. The added analyte concentration should be
the same as that used in the laboratory fortified blank.
9.4.2 Calculate the percent recovery for each analyte, corrected
for concentrations measured in the unfortified sample, and
compare these values to the designated LFM recovery range
90-110%. Percent recovery may be calculate using the
following equation:
R =
CS-C
x 100
where, R - percent recovery.
Cs » fortified sample concentration.
C = sample background concentration.
s = concentration equivalent of analyte added to
sample.
9.4.3 If the recovery of any analyte falls outside the designated
LFM recovery range and the laboratory performance for that
analyte is shown to be in control (Sect. 9.3), the recovery
problem encountered with the LFM is judged to be either
matrix or solution related, not system related.
9.4.4 Where reference materials are available, they should be
analyzed to provide additional performance data. The
analysis of reference samples is a valuable tool for
demonstrating the ability to perform the method acceptably.
350.1-9
-------
10.0 CALIBRATION AND STANDARDIZATION
10.1 Prepare a series of at least 3 standards, covering the desired
range, and a blank by diluting suitable volumes of standard
solutions (7.12, 7.13) to 100 ml with reagent water.
10.2 Process standards and blanks as described in Sect. 11, Procedure.
10.3 Set up manifold as shown in Figure 1.
10.4 Prepare flow system as described in Sect, 11, Procedure.
10.5 Place appropriate standards in the sampler in order of decreasing
concentration and perform analysis.
10.6 Prepare standard curve by plotting instrument response against
concentration values. A calibration curve may be fitted to the
calibration solutions concentration/response data using computer or
calculator based regression curve fitting techniques. Acceptance or
control limits should be established using the difference between
the measured value of the calibration solution and the "true value"
concentration.
10.7 After the calibration has been established, it must be verified by
the analysis of a suitable QCS. If measurements exceed ± 10% of the
established QCS value, the analysis should be terminated and the
instrument recalibrated. The new calibration must be verified
before continuing analysis. Periodic reanalysis of the QCS is
recommended as a continuing calibration check.
11.0 PROCEDURE
11.1 Preparation of equipment: Add 500 ml of reagent water to an 800-mL
Kjeldahl flask. The addition of boiling chips that have been
previously treated with dilute NaOH will prevent bumping. Steam out
the distillation apparatus until the distillate shows no trace of
ammon i a.
11.2 Sample preparation: Remove the residual chorine in the sample by
adding dechlorinating agent (7.5) equivalent to the chlorine
residual. To 400 ml of sample add 1 N NaOH (7.4), until the pH is
9.5, check the pH during addition with a pH meter or by use of a
short range pH paper.
11.3 Distillation: Transfer the sample, the pH of which has been
adjusted to 9.5, to an 800-mL Kjeldahl flask and add 25 ml of the
borate buffer (7.3). Distill 300 ml at the rate of 6-10 mL/min.
into 50 mL of 2% boric acid (7.2) contained in a 500-mL Erlenmeyer
flask.
NOTE 4: The condenser tip or an extension of the condenser tip must
extend below the level of the boric acid solution.
350.1-10
-------
11.4 Since the intensity of the color used to quantify the concentration
is pH dependent, the acid concentration of the wash water and the
standard ammonia solutions should approximate that of the samples.
11.5 Allow analysis system to warm up as required. Feed wash water
through sample line.
11.6 Arrange ammonia standards in sampler in order of decreasing
concentration of nitrogen. Complete loading of sampler tray with
unknown samples.
11.7 Switch sample line from reagent water to sampler and begin analysis.
12.0 DATA ANALYSIS AND CALCULATIONS
12.1 Prepare a calibration curve by plotting instrument response
against standard concentration. Compute sample concentration by
comparing sample response with the standard curve. Multiply answer
by appropriate dilution factor.
12.2 Report only those values that fall between the lowest and the
highest calibration standards. Samples exceeding the highest
standard should be diluted and reanalyzed.
12.3 Report results in mg NH3-N/L.
13.0 METHOD PERFORMANCE
13.1 In a single laboratory (EMSL-Cincinnati), using surface water
samples at concentrations of 1.41, 0.77, 0.59 and 0.43 mg NHj-N/L,
the standard deviation was ± 0.005.
13.2 In a single laboratory (EMSL-Cincinnati), using surface water
samples at concentrations of 0.16 and 1.44 mg NH3-N/L, recoveries
were 107% and 99%, respectively.
13.3 The interlaboratory precision and accuracy data in Table 1 were
developed using a reagent water matrix. Values are in mg NH3-N/L.
14.0 POLLUTION PREVENTION
14.1 Pollution prevention encompasses any technique that reduces or
eliminates the quantity or toxicity of waste at the point of
generation. Numerous opportunities for pollution prevention exist
in laboratory operation. The EPA has established a preferred
hierarchy of environmental management techniques that places
pollution prevention as the management option of first choice.
Whenever feasible, laboratory personnel should use pollution
prevention techniques to address their waste generation. When
wastes cannot be feasibly reduced at the source, the Agency
recommends recycling as the next best option.
350.1-11
-------
14.2 The quantity of chemicals purchased should be based on expected
usage during its shelf life and disposal cost of unused material.
Actual reagent preparation volumes should reflect anticipated usage
and reagent stability.
14.3 For information about pollution prevention that may be applicable to
laboratories and research institutions, consult "Less is Better:
Laboratory Chemical Management for Waste Reduction," available from
the American Chemical Society's Department of Government
Regulations and Science Policy, 1155 16th Street N.W., Washington
D.C. 20036, (202)872-4477.
15.0 WASTE MANAGEMENT
15.1 The U.S. Environmental Protection Agency requires that laboratory
waste management practices be conducted consistent with all
applicable rules and regulations. Excess reagents, samples and
method process wastes should be characterized and disposed of in an
acceptable manner. The Agency urges laboratories to protect the
air, water and land by minimizing and controlling all releases from
hoods, and bench operations, complying with the letter and spirit of
any waste discharge permit and regulations, and by complying with
all solid and hazardous waste regulations, particularly the
hazardous waste identification rules and land disposal
restrictions. For further information on waste management consult
the "Waste Management Manual for Laboratory Personnel," available
from the American Chemical Society at the address listed in Sect.
14.3.
16.0 REFERENCES
1. Hiller, A., and Van Slyke, D., "Determination of Ammonia in Blood,"
J. Biol. Chem. 102. p. 499 (1933).
2. O'Connor, B., Dobbs, R., Villiers, B., and Dean. R., "Laboratory
Distillation of Municipal Waste Effluents," JWPCF 39, R 25 (1967).
3. Fiore, J., and O'Brien, J.E., "Ammonia Determination by Automatic
Analysis," Wastes Engineering 33_, p. 352 (1962).
4. A Wetting Agent Recommended and Supplied by the Technicon
Corporation for Use in AutoAnalyzers.
5. ASTM "Manual on Industrial Water and Industrial Waste Water," 2nd
Ed., 1966 printing, p. 418.
6. Booth, R.L., and Lobring. L.B., "Evaluation of the AutoAnalyzer II:
A Progress Report" in Advances in Automated Analysis: 1972
Technicon International Congress, Vol. 8, p. 7-10, Mediad
Incorporated, Tarrytown, N.Y., (1973).
350.1-12
-------
7. Standards Methods for the Examination of Water and Wastewater, 18th
Edition, p. 4-77, Methods 4500 NH3 B and H (1992).
8. Annual Book of ASTM Standards, Part 31, "Water," Standard D1426-
79(C).
9. Code of Federal Regulations 40, Ch. 1, Pt. 136, Appendix B.
350.1-13
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17.0 TABLES. DIAGRAMS. FLOWCHARTS. AND VALIDATION DATA
TABLE 1. INTERLABORATORY PRECISION AND ACCURACY DATA
NUMBER OF
VALUES
REPORTED
134
157
136
195
142
159
156
200
196
156
142
199
TRUE
VALUE
(T)
0.270
0.692
1.20
1.60
3.00
3.50
3.60
4.20
8.76
11.0
13.0
18.0
MEAN
(X)
0.2670
0.6972
1.2008
1.6095
3.0128
3.4991
3.5955
4.2271
8.7257
11.0747
12.9883
17.9727
RESIDUAL
FOR X
-0.0011
0.0059
0.0001
0.0076
0.0069
-0.0083
-0.0122
0.0177
-0.0568
0.0457
-0.0465
-0.0765
STANDARD
DEVIATION
(S)
0.0342
0.0476
0.0698
0.1023
0.1677
0.2168
0.1821
0.2855
0.4606
0.5401
0.6961
1.1635
RESIDUAL
FOR S
0.0015
-0.0070
-0.0112
0.0006
-0.0067
0.0165
-0.0234
0.0488
-0.0127
-0.0495
0.0027
0.2106
REGRESSIONS: X = 1.003T - 0.003, S = 0.052T + 0.019
350.1-14
-------
u
5
i
ii
8
E
RUSSIE
g
« 8
350.1-15
-------
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METHOD 551.1
DETERMINATION OF CHLORINATION DISINFECTION BYPRODUCTS,
CHLORINATED SOLVENTS, AND HALOGENATED PESTICIDES/
HERBICIDES IN DRINKING WATER BY LIQUID-LIQUID
EXTRACTION AND GAS CHROMATOGRAPHY WITH ELECTRON-
CAPTURE DETECTION
Revision 1.0
J.W. Hodgeson, A.L. Cohen - Method 551, (1990)
D.J. Munch (USEPA, Office of Water) and D.P. Hautman (International
Consultants, Inc.) - Method 551.1, (1995)
NATIONAL EXPOSURE RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
551.1-1
-------
METHOD 551.1
DETERMINATION OF CHLORINATION DISINFECTION BYPRODUCTS, CHLORINATED SOLVENTS,
AND HALOGENATED PESTICIDES/HERBICIDES IN DRINKING WATER BY LIQUID-LIQUID
EXTRACTION AND GAS CHROMATOGRAPHY WITH ELECTRON-CAPTURE DETECTION
1. SCOPE AND APPLICATION
1.1 This method (1-9) is applicable to the determination of the
following analytes in finished drinking water, drinking water during
intermediate stages of treatment, and raw source water. The
particular choice of analytes from this list should be a function of
the specific project requirements.
Disinfection Byproducts fDBPsl;
Analvte CAS No.
Trihalomethanes Chloroform 67-66-3
Bromodichloromethane 75-27-4
Bromoform 75-25-2
Dibromochloromethane 124-48-1
Haloacetonitriles Bromochloroacetonitrile 83463-62-1
Dibromoacetonitrile 3252-43-5
Dichloroacetonitrile 3018-12-0
Trichloroacetonitrile 545-06-2
Other DBPs Chloral Hydrate 75-87-6
Chloropicrin 76-06-2
1,1-Di chloro-2-propanone 513-88-2
l,l,l-Trichloro-2- 918-00-3
propanone
Chlorinated Solvents;
Carbon Tetrachloride 56-23-5
l,2-Dibromo-3- 96-12-8
chloropropane [DBCP]
1,2-Dibromoethane [EDB] 106-93-4
Tetrachloroethylene 127-18-4
1,1,1-Trichloroethane 71-55-6
1,1,2-Trichloroethane 79-00-5
Trichloroethylene 79-01-6
1,2,3-Trichloropropane 96-18-4
Pesticides/Herbicides:
Alachlor 15972-60-8
Atrazine 1912-24-9
Bromacil 314-40-9
Cyanazine 21725-46-2
Endrin 72-20-8
# Endrin Aldehyde 7421-93-4
Endrin Ketone 53494-70-5
Heptachlor 76-44-8
Heptachlor Epoxide 1024-57-3
Hexachlorobenzene 118-74-1
551.1-2
-------
Hexachlorocyclopentadi ene 77-47-4
Lindane (gamma-BHC) 58-89-9
Metolachlor 51218-45-2
Metribuzln 21087-64-9
Methoxychlor 72-43-5
Simazine 122-34-9
Trifluralin 1582-09-8
1.2 This analyte list includes twelve commonly observed chlorination
disinfection byproducts (3,4), eight commonly used chlorinated
organic solvents and sixteen halogenated pesticides and herbicides.
1.3 This method is intended as a stand-alone procedure for either the
analysis of only the trihalomethanes (THMs) or for all the
chlorination disinfection by-products (DBPs) with the chlorinated
organic solvents or as a procedure for the total analyte list. The
dechlorination/preservation technique presented in section 8 details
two different dechlorinating agents. Results for the THMs and the
eight solvents may be obtained from the analysis of samples
employing either dechlorinating agent. (Sect. 8.1.2)
1.4 After an analyte has been identified and quantitated in an unknown
sample with the primary GC column (Sect. 6.9.2.1) qualitative
confirmation of results is strongly recommended by gas
chromatography/mass spectrometry (GC/MS) (10,11), or by GC analysis
using a dissimilar column (Sect. 6.9.2.2).
1.5 The experimentally determined method detection limits (MDLs) (12)
for the above listed analytes are provided in Tables 2 and 8.
Actual HDL values will vary according to the particular matrix
analyzed and the specific instrumentation employed.
1.6 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 Sect. 9.4.
1.7 Methyl-t-butyl ether (MTBE) is recommended as the primary extraction
solvent in this method since it effectively extracts all of the
target analytes listed in Sect. 1.1. However, due to safety
concerns associated with MTBE and the current use of pentane by some
laboratories for certain method analytes, pentane is offered as an
optional extraction solvent for all analytes except chloral hydrate.
If project requirements specify the analysis of chloral hydrate,
MTBE must be used as the extracting solvent. This method includes
sections specific for pentane as an optional solvent.
2. SUMMARY OF METHOD
2.1 A 50 ml sample aliquot is extracted with 3 ml of MTBE or 5 ml of
pentane. Two /iL of the extract is then injected into a GC equipped
551.1-3
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with a fused silica capillary column and linearized electron capture
detector for separation and analysis. Procedural standard
calibration is used to quantitate method analytes.
2.2 A typical sample can be extracted and analyzed by this method in 50
min for the chlorination by-products/chlorinated solvents and 2 hrs.
for the total analyte list. Confirmation of the eluted compounds
may be obtained using a dissimilar column (6.9.2.2) or by the use of
GC-MS. Simultaneous confirmation can be performed using dual
primary/confirmation columns installed in a single injection port
(Sect. 6.9.3) or a separate confirmation analysis.
3. DEFINITIONS
3.1 INTERNAL STANDARD (IS) — A pure analyte(s) added to a sample,
extract, or standard solution in known amount(s) and used to measure
the relative responses of other method analytes and surrogates that
are components of the same sample or solution. The internal
standard must be an analyte that is not a sample component.
3.2 SURROGATE ANALYTE (SA) -- A pure analyte(s), which is extremely
unlikely to be found in any sample, and which is added directly to a
sample aliquot in known amount(s) before extraction or other
processing and is measured with the same procedures used to measure
other sample components. The purpose of a surrogate analyte is to
monitor method performance with each sample.
3.3 LABORATORY DUPLICATES (LD1 and LD2) — Two sample aliquots, taken in
the laboratory from a single sample bottle, and analyzed separately
with identical procedures. Analyses of LD1 and LD2 indicate
precision associated with laboratory procedures, but not with sample
collection, preservation, or storage procedures. This method
cannot utilize laboratory duplicates since sample extraction must
occur in the sample vial and sample transfer is not possible due to
analyte volatility,
3.4 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 measure of the precision associated
with sample collection, preservation and storage, as well as with
laboratory procedures. Since laboratory duplicates cannot be
analyzed, the collection and analysis of field duplicates for this
method is critical.
3.5 LABORATORY REAGENT BLANK (LRB) ~ An aliquot of reagent water, or
other blank matrix, 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.
551.1-4
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3.6 FIELD REAGENT BLANK (FRB) — Reagent water, or other blank matrix,
that Is placed in a sample container in the laboratory and treated
as a sample In all respects, Including shipment to sampling site,
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.
3.7 LABORATORY FORTIFIED .BLANK (LFB) — An aliquot of reagent water, or
other blank matrix, 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 analyte quantitation at various concentrations including
the required method detection limit.
3.8 LABORATORY FORTIFIED SAMPLE MATRIX (LFM) — An aliquot of an
environmental 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.
3.9 STOCK STANDARD SOLUTION (SSS) — A concentrated solution containing
one or more method analytes which is prepared in the laboratory
using assayed reference materials or purchased as certified from a
reputable commercial source.
3.10 PRIMARY DILUTION STANDARD SOLUTION (PDS) — 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.
3.11 CALIBRATION STANDARD (CAL) — A solution prepared from the primary
dilution standard solution or stock standard solutions and the
internal standard(s) and surrogate analyte(s). The. CAL solutions
are used to calibrate the instrument response with respect to
analyte concentration.
3.12 QUALITY CONTROL SAMPLE (QCS) -- A solution of method analytes which
is used to fortify an aliquot of LRB or sample matrix. The QCS is
obtained from a source external to the laboratory and different from
the source of calibration standards. It is used to check laboratory
performance with externally prepared test materials.
3.13 LABORATORY PERFORMANCE CHECK SOLUTION (LPC) - A solution of
selected method analytes, surrogate(s), internal standard(s), or
other test substances used to evaluate the performance of the
instrument system with respect to a defined set of method criteria.
551.1-5
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3.14 METHOD DETECTION LIMIT (MDL) — The minimum concentration of an
analyte that can be identified, measured and reported with 99%
confidence that the analyte concentration is greater than zero.
(Appendix B to 40 CFR Part 136)
3.15 ESTIMATED DETECTION LIMIT (EDL) — Defined as either the MDL or a
level of compound in a sample yielding a peak in the final extract
with a signal to noise (S/N) ratio of approximately 5, whichever is
greater.
3.16 PROCEDURAL STANDARD CALIBRATION — A calibration method where
aqueous calibration standards are prepared and processed (e.g.
purged,extracted, and/or derivatized) in exactly the same manner as
a sample. All steps in the process from addition of sampling
preservatives through instrumental analyses are included in the
calibration. Using procedural standard calibration compensates for
any inefficiencies in the processing procedure.
4. INTERFERENCES
4.1 Impurities contained in the extracting solvent usually account for
the majority of the analytical problems. Each new bottle of solvent
should be analyzed for interferences before use. An interference
free solvent is a solvent containing no peaks yielding data at > MDL
(Tables 2 and 8) at the retention times of the analytes of interest.
Indirect daily checks on the extracting solvent are obtained by
monitoring the laboratory reagent blanks (Sect. 9.3). Whenever an
interference is noted in the reagent blank, the analyst should
analyze the solvent separately to determine if the source of the
problem is the solvent or another reagent.
4.2 Glassware must be scrupulously cleaned (13). Clean all glassware 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 thoroughly rinsing with tap and reagent water. Drain dry, and
heat in an oven or muffle furnace at 400°C for 1 hr. Do not muffle
volumetric ware but instead rinse three times with HPLC grade or
better,acetone. Thoroughly rinsing all glassware with HPLC grade or
better acetone may be substituted for heating provided method blank
analysis confirms no background interferant contamination is
present. After drying and cooling, seal and store all glassware in
. a clean environment free of all potential contamination. To prevent
any accumulation of dust or other contaminants, store glassware
inverted on clean aluminum foil or capped with aluminum foil.
4.3 Commercial lots of the extraction solvents (both MTBE and pentane)
often contain observable amounts of chlorinated solvent impurities,
e.g., chloroform, trichloroethylene, carbon tetrachloride. When
present, these impurities can normally be removed by double
distillation.
551.1-6
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4.4 This liquid/liquid extraction technique efficiently extracts a wide
boiling range of non-polar and polar organic components of the
sample. Thus, confirmation is quite important, particularly at
lower analyte concentrations. A confirmatory column (6.9.2.2) is
suggested for this purpose. Alternatively, GC/MS may also be used
for confirmation if sufficient concentration of analyte is present.
4.5 Special care must be taken in the determination of endrin since it
has been reported to breakdown to aldo and keto derivatives upon
reaction with active sites in the injection port sleeve (14). The
active sites are usually the result of micro fragments of the
injector port septa and high boiling sample residual deposited in
the injection port sleeve or on the inner wall at the front of the
capillary column. The degradation of endrin is monitored using the
Laboratory Performance Check Standard (Sect. 9.2).
4.6 Interfering and erratic peaks have been observed in method blanks
within the retention windows of metribuzin, alachlor, cyanazine and
heptachlor. These are believed to be due to phthalate
contamination. This contamination can be reduced by paying special
attention to reagent preparation (See solvent rinsing the dry buffer
and the dechlorination/ preservative salts, Sect. 7.1.7.5) and
elimination of all forms of plastic from the procedure (i.e. HOPE
bottles, plastic weighing boats, etc.). After NaCl or Na2S04 is
muffled or phosphate buffer and dechlorination/preservative salts
are solvent rinsed, they should be stored in sealed glass
containers. NaCl, Na2S04, phosphate buffer and dechlorination/
preservative salts should be weighed using glass beakers, never
plastic weighing boats.
5. 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 (15-17) for the information of the analyst.
5.2 The following have been tentatively classified as known or suspected
human or mammalian carcinogens:
Chloroform, l,2-Dibromo-3-chloropropane, 1,2-Dibromoethane,
heptachlor, and hexachlorobenzene.
5.3 The toxicity of the extraction solvent, MTBE, has not been well
defined. Susceptible individuals may experience adverse affects
upon skin contact or inhalation of vapors. Therefore, protective
clothing and gloves should be used and MTBE should be used only in a
chemical fume hood or glove box. The same precaution applies to
pure standard materials.
551.1-7
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6. EQUIPMENT AND SUPPLIES (All specifications in Sections 6 and 7 are
suggested. Catalogue numbers are included for illustration only.)
6.1 SAMPLE CONTAINERS - 60-mL screw cap glass vials (Kimble #60958A-16,
Fisher #03-339-5E or equivalent) each equipped with size 24-400 cap
and PTFE-faced septa (Kimble #73802-24400, Fisher #03-340-14A or
equivalent)." Prior to use or following each use, wash vials and
septa with detergent and tap water then rinse thoroughly with
distilled water. Allow the vials and septa to dry at room
temperature, place only the vials in an oven and heat to 400°C for
30 min. After removal from the oven allow the vials to cool in an
area known to be free of organics. After rinsing caps with
distilled water, rinse in a beaker with HPLC grade or better acetone
and place in a drying oven at 80°C for 1 hr.
6.2 VIALS -. Autosampler, 2.0-mL vial with screw or crimp cap and a
teflon faced septa.
6.3 MICRO SYRINGES - 10 /iL, 25 ML, 50 /iL, 100 /iL, 250 pi, and 1000 fjl.
6.4 PIPETTES - 3.0 mL or 5.0 ml, type A, TO, glass.
6.5 VOLUMETRIC FLASK - 10 mL, 100 mL, 250 mL, 500 mL glass stoppered.
6.6 DISPOSABLE PASTEUR PIPETS - 9 inch, used for extract transfer.
6.7 STANDARD SOLUTION STORAGE CONTAINERS - 30-mL Boston round, amber
glass'bottles with TFE-lined caps or equivalent.
6.8 BALANCE - Analytical, capable of accurately weighing to the nearest
0.0001 g.
6.9 GAS CHROMATOGRAPHY SYSTEM
6.9.1 The GC must be capable of temperature programming and should
be equipped with a linearized electron capture detector
(ECD), fused silica capillary column, and on-column or
splitless injector (splitless mode, 30 sec. delay). If
simultaneous confirmation is employed the GC must have a
second ECD. An auto-sampler/injector is desirable.
6.9.1.1 SPECIAL PRECAUTION: During method development, a
problem was encountered with the syringe on the
autosampler. The syringe plunger, after repeated
sample extract injections, developed resistance when
withdrawn or inserted into the syringe barrel. This
resistance was due to salt deposits in the syringe
barrel which were left behind following the
evaporation of hydrated MTBE. To minimize this
problem, a unique syringe wash procedure was
employed. After sample injection, the syringe was
first rinsed three times with reagent water then
551.1-8
-------
three times with MTBE. This effectively removed all
the residual salt after each injection from the
syringe and surmounted the problem. Some
autosampler designs may not encounter this problem
but this precaution has been mentioned to alert the
analyst. When pentane was used as the extraction
solvent, this was not a problem.
6.9.2 Two GC columns are recommended. Column A is recommended as
the primary analytical column unless routinely occurring
analytes are not adequately resolved. Column 8 is
recommended for use as a confirmatory column when GC/MS
confirmation is not sensitive enough or unavailable. Other
GC columns or conditions may be employed provided adequate
analyte resolution is attained and all the quality assurance
criteria established in Sect. 9 are met.
6.9.2.1 Column A - 0.25 mm ID x 30 m fused silica capillary
with chemically bonded methyl polysiloxane phase
(J&W, DB-1, 1.0 m film thickness or equivalent). As
a result of the different boiling points of MTBE
(b.p. 55°C) and pentane (b.p. 35°C), two different
GC oven temperature programs are specified in Table
1 for MTBE and Table 12 for pentane. Retention
times for target analytes were slightly different
using the pentane oven temperature program but
elution order, analyte resolution, and total
analysis time were not effected. Injector
temperature: 200°C equipped with 4 mm ID
deactivated sleeve with wool plug (Restek #20781 for
HP GC's or equivalent). This sleeve design was
found to give better analyte response than the
standard 2 mm sleeve. DAtector temperature: 290°C.
6.9.2.2 Column B - 0.25 mm ID x 30 m with chemically bonded
6 % cyanopropylphenyl/94 % dimethyl polysiloxane
phase (Restek, Rtx-1301, 1.0 fun film thickness or
equivalent). The column oven was temperature
programmed exactly as indicated for column A (Tables
1 and 12). Injector and detector temperatures at
200°C and 290°C, respectively. The same
temperature program was utilized to allow for
simultaneous confirmation analysis.
6.9.3 To perform simultaneous confirmation from a single injection
onto both the primary and confirmation columns, two injector
setups can be employed.
6.9.3.1 Using a two hole graphite ferrule (Restek #20235, or
equivalent) both columns can be inserted into one
injection port. To ensure the column ends are
centered in the injection port sleeve and not angled
551.1-9
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to the side, an inlet adaptor fitting is installed
at the base of the injection port (Restek #20633, or
equivalent). Use caution when installing columns in
this manner to ensure the column does not break at
the base of the injector due to the two columns
twisting as the ferrule nut is tightened. To
minimize this hazard, the ferrule nut can be reverse
twisted four to five times once the ferrule has been
seated.
6.9.3.2 An alternate procedure involves installing a 1 meter
portion of 0.25 mm deactivated, uncoated fused
silica capillary tubing (Restek #10043, or
equivalent) into the injector as a normal single
column is installed. Then using a Y-press tight
union (Restek #20403 or equivalent) join the 1 meter
uncoated column to the primary and secondary
columns. Using this procedure will reduce detection
limits when compared to the procedure outline in
6.9.3.1 since only one column is positioned in the .
injection port to receive the injected sample
extract.
6.9.4 The analyst is permitted to modify GC columns, GC conditions,
internal standard or surrogate compounds. Each time such
method modifications are made, the analyst must repeat the
procedures in Sect. 9.4.
7. REAGENTS AND STANDARDS
7.1 REAGENTS
7.1.1 MTBE - High purity grade. It may be necessary to double
distill the solvent if impurities are observed which coelute
with some of the more volatile compounds.
7.1.2 Pentane (optional extraction solvent) - High purity grade. It
may be necessary to double distill the solvent if impurities
are observed which coelute with some of the more volatile
compounds.
7.1.3 Acetone - High purity, demonstrated to be free of analytes.
7.1.4 Methanol - High purity, demonstrated to be free of analytes.
7.1.5 Sodium Chloride, NaCl - ACS Reagent Grade. Before using a
batch of NaCl, place in muffle furnace, increase temperature
to 400°C and hold for 30 min. Store in a capped glass
bottle, not in a plastic container.
7.1.6 Sodium Sulfate, Na^SC* - ACS Reagent Grade. Before using a
batch of Na2S04, place in muffle furnace, increase
551.1-10
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temperature to 400°C and hold for 30 rain.
glass bottle not in a plastic container.
7.1.7 Sample Preservation Reagents
Store in a capped
7.1.7.1 Phosphate buffer - Used to lower the sample matrix
pH to 4.8-5.5 in order to inhibit base catalyzed
degradation of the haloacetonitriles (7), some of
the chlorinated solvents, and to standardize the pH
of all samples. Prepare a dry homogeneous mixture
of 1% Sodium Phosphate, dibasic (Na2HP04)/99%
Potassium Phosphate, monobasic (KH2P04) by weight
(example: 2 g NazHP04 and 198 g KH2P04 to yield a
total weight of 200 g) Both of these buffer salts
should be in granular form and of ACS grade or
better. Powder would be ideal but would require
extended cleanup time as outlined below in Sect.
7.1.7.5 to allow for buffer/solvent settling.
7.1.7.2 Ammonium Chloride, NH4C1, ACS Reagent Grade. Used
to convert free chlorine to monochloramine.
Although this is not the traditional dechlorination
mechanism, ammonium chloride is categorized as a
dechlorinating agent in this method.
7.1.7.3 Sodium Sulfite, Na2S03, ACS Reagent Grade. Used as
a dechlorinating agent for chloral hydrate sample
analysis.
7.1.7.4 To simplify the addition of 6 mg of the
dechlorinating agent to the 60 ml vial, the
dechlorinating salt is combined with the phosphate
buffer as a homogeneous mixture. Add 1.2 g of the
appropriate dechlorinating agent to 200 g of the
phosphate buffer. When 1 g of the buffer/
dechlorinating agent mixture are added to the 60-mL
sample vial, 6 mg of the dechlorinating agent are
included reflecting an actual concentration of 100
mg/L. Two separate mixtures are prepared, one
containing ammonium chloride and the other with
sodium sulfite.
7.1.7.5 If background contaminants are detected in the salts
listed in Sections 7.1.7.1 through 7.1.7.3, a
solvent rinse cleanup procedure may be required.
These contaminants may coelute with some of the high
molecular weight herbicides and pesticides. These
salts cannot be muffled since they decompose when
heated to 400°C. This solvent rinsing procedure is
applied to the homogeneous mixture prepared in Sect.
7.1.7.4.
551.1-11
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7.2
7.3
NOTE: If a laboratory is not conducting analyses
for the high molecular weight herbicides and
pesticides, this cleanup may not be required if no
interfering peaks are observed within the retention
time window (Sect.12.2) for any target analytes in
the laboratory reagent blank.
SOLVENT RINSE CLEANUP PROCEDURE
Prepare two separate homogeneous mixtures of the
phosphate buffer salts (Sect. 7.1.7.1) in a 500-mL
beaker. To one, add the correct amount of ammonium
chloride and to the other add the correct amount of
sodium sulfite. Three separate solvents are then
used to rinse the mixture. (This solvent rinsing
must be performed in a fume hood or glove box.)
First, add approx. 100 ml of methanol, or enough to
cover the salt to a depth of approx. 1 cm, and using
a clean spatula, stir the solvent salt mixture for 1
minute. Allow the buffer/solvent mixture to settle
for 1 minute and then decant the methanol, being
careful not to pour off the rinsed buffer. It may
be necessary to perform this procedure up to four
times with methanol. NOTE: By softly lifting and
tapping the base of the beaker against the fume hood
counter surface, more of the solvent is brought to
the surface of the buffer. Next, perform the
identical procedure up to two times using acetone.
Finally, perform two final rinses with the
appropriate extracting solvent (MTBE or Pentane).
After the final solvent rinse, place the "wet"
buffer on a hot plate at approx. 60°C for 30 minutes
or until dry. Stir the mixture every 5 minutes to
aid the evaporation of excess solvent. Once dry,
place the buffer in a glass bottle with either a
ground glass stopper or TFE faced septum.
REAGENT WATER - Reagent water is defined as purified water which
does not contain any measurable quantities of any target analytes or
any other interfering species.
7.2.1 A Millipore Super-Q water system or its equivalent may be
used to generate deionized reagent water. Distilled water
that has been charcoal filtered may also be suitable.
7.2.2 Test reagent water each day it is used by analyzing according
to Sect. 11.
STOCK STANDARD SOLUTIONS (SSS)- These solutions may be obtained as
certified solutions or prepared from neat-materials using the
following procedures:
551.1-12
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7.3.1 For analytes which are solids in their pure form, prepare
stock standard solutions (1 mg/mL) by accurately weighing
approximately 0.01 g of pure material in a 10-mL volumetric
flask. Dilute to volume with acetone. Due to the low
solubility of simazine, this stock should be prepared at 0.5
mg/mL by weighing 0.005 g diluted to volume with acetone in a
10-mL volumetric flask. Alternatively, simazine stock
standard solutions may be prepared in ethyl acetate at
approximately 0.01 g/10 ml. Stock standard solutions for
analytes which are liquid in their pure form at room
temperature can be accurately prepared in the following
manner.
7.3.1.1 Place about 9.8 mL of acetone into a 10-mL ground-
glass stoppered volumetric flask. Allow the flask
to stand, unstoppered, for about 10 min to allow
solvent film to evaporate from the inner walls of
the volumetric flask, and weigh to the nearest 0.1
mg.
7.3.1.2 Use a 10-pL syringe and immediately add 10.0 jjl of
standard material to the flask by keeping the
syringe needle just above the surface of the
acetone. Caution should be observed to be sure that
the standard material falls dropwise directly into
the acetone without contacting the inner wall of the
volumetric flask.
7.3.1.3 Reweigh, dilute to volume, stopper, then mix by
inverting the flask several times. Calculate the
concentration in milligrams per milliliter from the
net gain in weight. Final concentration should be
between 0.800 - 1.50 mg/mL.
7.3.2 Larger volumes of standard solution may be prepared at the
discretion 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.
7.3.3 Commercially prepared stock standards can be used at any
concentration if they are certified by the manufacturer or by
an independent source. When purchasing commercially prepared
stock standards, every effort should be made to avoid
solutions prepared in methanol (chloral hydrate is an
exception, Sect. 7.3.3.1). Methanol can cause degradation of
most of the haloacetonitriles. In addition, some commercial
suppliers have reported instability with solutions of
simazine and atrazine prepared in methanol (18). For these
reasons, acetone should be used as the primary solvent for
stock standard and primary dilution standard preparation and
551.1-13
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all sources of methanol Introduction into these acetone
solutions should be eliminated.
7.3.4
7.3.5
7.3.6
7.3.3,1 It is extremely difficult to acquire chloral hydrate
in its pure form since it is classified as a
controlled substance. Consequently, if pure chloral
hydrate cannot be acquired, a commercially prepared
solution of this analyte (most often at 1.0 mg/mL)
must be purchased. Most manufactures provide
certified chloral hydrate solutions in methanol.
Since chloral hydrate is unstable, standards from a
separate vendor must be utilized to confirm the
accuracy of the primary supplier's solution.
Outside source stock solutions, which are independently
prepared or purchased from an outside source different from
the source for the original stock standard solutions, must be
used as a means of verifying the accuracy of the original
stock standard solutions for all analytes. Prepare a
dilution of both stocks in acetone and perform a final
dilution in MTBE such that each stock dilution is at the same
concentration. Analyze as outlined in Section 11.3. The
relative percent difference (RPD as defined below) between
the analytes' response (area counts) from both solutions
should not exceed 25% for any one analyte. The RPD must be
less than 20% for 90% or greater of the total number of
target analytes analyzed.
(DUP 1 - DUP 2)
((DUP 1 + DUP 2) / 2)
x 100
7:3.4.1
If this criteria cannot be met, a third outside
source should be purchased and tested in the same
manner. When two sources of stock solutions agree,
the accuracy of the stock solutions is confirmed.
This should be done prior to preparing the primary
dilution standards.
Stock Solution of Surrogate - Prepare a stock solution of the
surrogate standard in acetone by weighing approx. 0.010 g
decaf luorobiphenyl in a 10-mL volumetric flask. When diluted
to volume this yields a concentration of 1.00 mg/mL. t
Alternate surrogate analytes may be selected provided they
are similar in analytical behavior to the compounds of
interest, are highly unlikely to be found in any sample, and
do not coelute with target analytes.
Stock Solution of Internal Standard (IS) - Use of an IS is
optional when MTBE is the extraction solvent but mandatory if
pentane is used. This is due to the high volatility of
pentane when compared to MTBE (see boiling points, Sect.
551.1-14
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6.9.2.1). Prepare an internal standard stock solution of
bromofluorobenzene (BFB) in acetone. Since this compound is
a liquid at room temperature, the procedure outlined in
Sections 7.3.1.1 through 7.3.1.3 should be followed but add
approximately 65 pi of neat BFB rather than 10 //L as
specified in 7.3.1.2. When diluted to volume this yields a
concentration near 10.0 mg/mL. Alternate internal standard
analytes may be selected provided they are highly unlikely to
be found in any sample and do not coelute with target
analytes.
7.3.7 Transfer the stock standard solutions into Teflon-lined screw
cap amber bottles. Store at 4°C or less 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.
7.3.8 When stored in a freezer at < -10°Ct the THM stock standards
have been shown to be stable for up to six months. The other
analyte stock standards, with the exception of chloral
hydrate, have been shown to be stable for at least four
months when stored in a freezer (<-10°C). Chloral hydrate
stock standards, when stored in a freezer (<-10°C), have been
shown to be stable for two months, however, since freezers
can hold at various temperatures below -10°C, fresh chloral
hydrate standards should be initially prepared weekly, until
the stability of this analyte is determined for a specific
laboratory setting.
7.4 PRIMARY DILUTION STANDARDS (PDS) - Two separate groups of primary
dilution standards must be prepared; one set in acetone for all the
method analytes except chloral hydrate and the second set in
methanol for chloral hydrate. Although preparation of separate
chloral hydrate standards may seem laborious, due to the stability
problems encountered with this analyte, making fresh chloral hydrate
primary dilution standards is more efficient. Prepare primary
dilution standards by combining and diluting stock standards in
acetone (methanol for chloral hydrate). The primary dilution
standards should be prepared such that when 25 //L of this primary
dilution standard are added to 50 ml of buffered/dechlorinated
reagent water (Sect 10.1.2), aqueous concentrations will bracket the
working concentration range. Store the primary dilution standard
solutions in vials or bottles, with caps using TFE faced liners, in
a freezer (<-10°C) with minimal headspace and check frequently for
signs of deterioration or evaporation, especially just before
preparing calibration standards. The same comments on storage
stability in Sect. 7.3.8 apply to primary dilution standards.
7.4.1 SURROGATE PRIMARY DILUTION STANDARD - Dilute 500 ^L of the
surrogate stock solution to volume with acetone in a 50-mL
volumetric flask. This yields a primary dilution standard at
10.0 //g/mL. Addition of 50 i/L of this standard to 50 ml of
551.1-15
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aqueous sample yields a final concentration in water of 10.0
fjg/l. This solution is fortified into the aqueous sample
prior to extraction of all calibration standards (Sect.
10.1.3), quality control samples (Sect. 9), laboratory
reagent blanks (Sect. 9.3.1) and actual field samples (Sect.
11.1.3) in the extraction set.
7.4.2 INTERNAL STANDARD (IS) PRIMARY DILUTION STANDARD - Prepare a
IS primary dilution standard at 100 //g/mL by diluting the
appropriate amount of internal standard stock solution (500
/jl if stock is 10.0 mg/mL) to volume with acetone in a 50-mL
volumetric flask. When 10 ^L of this solution are added to
1,0 mL of extract, the resultant final concentration is 1.00
/yg/mL, The internal standard is used in order to perform an
internal standard calibration and is added to an analytically
precise volume of the extract following extraction. This
solution is added to all extracts.
7.4.3 Reserve approximately a 10 mL aliquot of the same lot of both
the acetone and methanol used in the preparation of the
primary dilution standards. When validating the accuracy of
the calibration standards (Sect. 7.3.4), fortify a laboratory
reagent blank with 25 //L of both the acetone and the methanol
which was used to prepare the primary dilution standards.
Analysis of this laboratory reagent blank will confirm no
target analyte contamination in the solvents used to prepare
the primary dilution standards.
7.5 LABORATORY PERFORMANCE CHECK SOLUTION (LPC) - To insure proper
instrument performance, a Laboratory Performance Check Solution is
prepared. This solution is prepared in MTBE for direct injection on
the GC and is used to evaluate the parameters of instrument
sensitivity, chromatographic performance, column performance and
analyte breakdown. These parameters are listed in Table 7 along
with the method analytes utilized to perform this evaluation, their
concentration in MTBE and the acceptance criteria. To prepare this
solution at the concentrations listed in Table 7, a double dilution
of the analyte stock solutions must be made. First prepare a
primary stock dilution mix at 1000 times the concentrations listed
in Table 7, by adding the appropriate volume of each stock solution
to a single 50-mL volumetric flask containing approximately 25 mL of
MTBE. Dilute to volume with MTBE. Then the LPC working solution is
prepared in MTBE by diluting 50 fjl of the primary stock dilution mix
in MTBE to 50-mL in a volumetric flask. The best way to accomplish
this is to add approximately 48 mL MTBE to the 50-mL volumetric
flask and add 50 //L of the primary stock dilution mix, then dilute
to volume with MTBE. Store this solution in a vial or bottle, with
TFE faced cap, in a freezer (<-10"C) with minimal headspace and
check frequently for signs of deterioration or evaporation.
7.5.1 If a laboratory is not conducting analyses for the high
molecular weight pesticides and herbicides, a modified LPC
551.1-16
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may be prepared. This modified LPC can omit the endrin
analyte breakdown component as well as the resolution
requirement for bromacil and alachlor under column
performance. In addition, substitute analytes in place of
lindane for the sensitivity check and
hexachlorocyclopentadiene for chromatographic performance can
be selected. These substitute compounds must meet the same
criteria as listed in table 7 with the concentration for
sensitivity check near the substitute analyte's EDL and the
concentration for chromatographic performance near 50 times
the substitute analyte's EOL. The column performance
criteria for resolution between bromodichloromethane and
trichloroethylene cannot be modified.
7.5.2 If pentane is selected as an alternate extraction solvent the
LPC must also be prepared in pentane.
8. SAMPLE COLLECTION. PRESERVATION. AND STORAGE *
8.1 SAMPLE VIAL PREPARATION
8.K1 To conduct analyses for the total analyte list, two sets of
60-mL vials must be prepared for sampling. One set of vials,
prepared for the analysis of all target analytes except
chloral hydrate, contains ammonium chloride as a
dechlorinating agent. Due to concerns over low recoveries
for chloral hydrate in matrices preserved with ammonium
chloride (Sect. 8.1.2), a separate sample set must be
collected and preserved with sodium sulfite. Both sets of
vials are prepared as follows.
8.1.1.1 Using the homogeneous phosphate
buffer/dechlorinating agent mixtures prepared in
Sect. 7.1.7.4, 0.60 g of the appropriate mixture are
added to the corresponding vials.
8.1.2 If the sample assay is for only the THMs and/or solvents,
either dechlorinating agent can be added. However, sodium
sulfite promotes the decomposition of the haloacetonitriles,
l,l-dichloro-2-propanone, l,l,l-trichloro-2-propanone and
chloropicrin and therefore ammonium chloride must be used as
the dechlorination reagent in their analysis. In addition,
some fortified matrices, dechlorinated with ammonium
chloride, have displayed recoveries of chloral hydrate which
have been up to 50% lower than expected, when compared to the
same sample matrix dechlorinated with sodium sulfite. In
other matrices, recoveries have been consistent regardless of
dechlorinating agent. The reason for these differences has
not been determined. Due to this uncertainty, a separate
sample, dechlorinated with 100 mg/L sodium sulfite must be
collected for the analysis of chloral hydrate.
* See Addendum page 551.1-71
551.1-17
-------
8.1.3 The dechlorinating agents, if not added within the
homogeneous mixture of the buffer, must be added to the
sampling vials as a dry salt. Solutions of the
dechlorinating agents should not be used due to concerns over
the stability of these salts dissolved in solution and the
potential chemical interactions of aqueous solutions of these
salts with the dry phosphate buffer.
8.1.4 Samples roust contain either 100 mg/L ammonium chloride or
sodium sulfite, as appropriate for the analysis being
performed. This amount will eliminate free chlorine residual
in typical chlorinated drinking water samples. If high
chlorine doses are used, such as in a maximum formation
potential test, additional dechlorinating reagent may be
required.
8.2 SAMPLE COLLECTION
8.2.1 Collect all samples in duplicate. Fill sample bottles to
just overflowing but take care not to flush out the buffer/
dechlorination reagents. No air bubbles should pass through
the sample as the bottle is filled, or be trapped in the
sample when the bottle is sealed.
8.2.2 When sampling from a water tap, open the tap and allow the
system to flush until the water temperature has stabilized
(usually about 3-5 min). Remove the aerator and adjust the
flow so that no air bubbles are visually detected in the
flowing stream.
8.2.3 When sampling from an open body of water, fill a 1-quart
wide-mouth glass bottle or 1-liter beaker with sample from a
representative area, and carefully fill duplicate 60-mL
sample vials from the container.
8.2.4 The samples must be chilled to 4°C on the day of collection
and maintained at that temperature until analysis. Field
samples that will not be received at the laboratory on the
day of collection must be packaged for shipment with
sufficient ice to ensure they will be at 4°C on arrival at
the laboratory. Synthetic ice (i.e. Blue ice) is not
recommended.
8.3 SAMPLE STORAGE/HOLDING TIMES
8.3.1 Store samples at 4°C and extracts in a freezer (<-10°C) until
analysis. The sample storage area must be free of organic
solvent vapors.
551.1-18
-------
8.3.2 Extract all samples within 14 days of collection and analyze
within 14 days following extraction. This applies to either
MTBE or pentane extracts). Samples not analyzed within these
time periods must be discarded and replaced.
9. QUALITY CONTROL
9.1 Each laboratory that uses this method is required to operate a
formal quality control (QC) program. Minimum QC requirements
include the laboratory performance check standard, initial
demonstration of laboratory capability, method detection limit
determination, analysis of laboratory reagent blanks, continuing
calibration check standard, laboratory fortified sample matrices,
field duplicates and monitoring surrogate and/or internal standard
peak response in each sample and blank. Additional quality control
practices may be added.
9.2 ASSESSING INSTRUMENT SYSTEM - LABORATORY PERFORMANCE CHECK STANDARD
(LPC). Prior to any sample analyses, a laboratory performance check
standard must be analyzed. The LPC sample contains compounds
designed to indicate appropriate instrument sensitivity, endrin
breakdown, column performance (primary column), and chromatographic
performance. LPC sample components and performance criteria are
listed in Table 7. Inability to demonstrate acceptable instrument
performance indicates the need for revaluation of the instrument
system. The sensitivity requirement is based on the Estimated
Detection Limits (EDLs) published in this method. If laboratory
EDLs differ from those listed in this method, concentrations of the
LPC standard must be adjusted to be compatible with the laboratory
EDLs. If endrin breakdown exceeds 20 %, the problem can most likely
be solved by performing routine maintenance on the injection port
including replacing the injection port sleeve, and all associated
seals and septa. If column or chromatographic performance criteria
cannot be met, new columns may need to be installed, column flows
corrected, or modifications adapted to the oven temperature program.
During early method development work, significant chromatographic
and column performance problems were observed while using a DB-1
column which had been used for several years for drinking water
extract analysis. By installing a new DB-1 column, these
performance problems were overcome. If the columns to be used for
this method have been used for several years or have had extended
use with extracts from harsh sample matrices (i.e. wastewater,
acidified sample extracts, hazardous waste samples) it may be
difficult to meet the criteria established for this LPC standard and
column replacement may be the best alternative.
9.3 LABORATORY REAGENT BLANKS (LRB). Before processing any samples, the
analyst must analyze an LRB to demonstrate that all glassware and
reagent interferences are under control. In addition, each time a
set of samples is extracted or reagents are changed, a LRB must be
analyzed. If the LRB produces a peak within the retention time
window of any analyte (Sect. 12.2) preventing the quantitation of
551.1-19
-------
that analyte, determine the source of the contamination and
eliminate the interference before processing samples. LRB samples
must' contain the appropriate buffer for the target analytes
(buffered/NH4Cl dechlorinated and/or buffered/Na2S03 dechlorinated
reagent water).
9.3.1 Prepare the two LRBs in the appropriate buffered/
dechlorinated reagent water. Add 50 /;!_ of surrogate primary
dilution standard (Sect. 7.4.1) to each blank and follow the
procedure outlined in Sect. 11.2.
9.4 INITIAL DEMONSTRATION OF CAPABILITY (IDC)
9.4.1 Preparation of the IDC Laboratory Fortified Blank (LFB).
Select a concentration for each of the target analyte which
is approximately 50 times the EDL or close to the expected
levels observed in field samples. Concentrations near
' analyte levels in Table 3.A are recommended. Prepare a LFB
by adding the appropriate concentration of the primary
dilution standard (Sect. 7.4) to each of four to seven 50 ml .
aliquots of buffered/NH4Cl dechlorinated reagent water.
Separate Na,S03 preserved matrices need not be analyzed
(Sect. 9.4.1.1). Analyze the aliquots according to the
method beginning in Section 11.
9.4.1.1 Chloral hydrate is included in the buffered/NH4Cl
dechlorinated reagent water, containing all the
other target analytes since no matrix induced
recovery problems have been found from reagent water
preserved with NH4C1.
9.4.2 Following procedural calibration standard analysis and
subsequent instrument calibration, analyze a set of at least
seven IDC samples and calculate'the mean percent recovery (R)
and the relative standard deviation of this recovery (RSD).
The percent recovery is determined as the ratio of the
measured concentration to the actual fortified concentration.
For each analyte, the mean recovery value must fall within
' the range of 80% to 120% and the RSD must not exceed 15 %.
For those compounds that meet these criteria, performance is
considered acceptable, and sample analysis may begin. For
those compounds that fail these criteria, this procedure must
be repeated using eight fresh samples until satisfactory
performance has been demonstrated.
9.4.3 The initial demonstration of capability is used primarily to
preclude a laboratory from analyzing and reporting unknown
samples without obtaining some experience with an unfamiliar
method. It is expected that as laboratory personnel gain
experience with this method, the quality of data will improve
beyond those specified in Sect. 9.4.2.
551.1-20
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8.3.2 Extract all samples within 14 days of collection and analyze
within 14 days following extractidn. This applies .to either
MTBE or pentane extracts). Samples not analyzed within these
time periods must be discarded and replaced.
9. QUALITY CONTROL
9.1 Each laboratory that uses this method is required to operate a
formal quality control (QC) program. Minimum QC requirements
include the laboratory performance check standard, initial
demonstration of laboratory capability, method detection limit
determination, analysis of laboratory reagent blanks, continuing
calibration check standard, laboratory fortified sample matrices,
field duplicates and monitoring surrogate and/or internal standard
peak response in each sample and blank. Additional quality control
practices may be added.
9.2 ASSESSING INSTRUMENT SYSTEM - LABORATORY PERFORMANCE CHECK STANDARD
(LPC). Prior to any sample analyses, a laboratory performance check
standard must be analyzed. The LPC sample contains compounds
designed to indicate appropriate instrument sensitivity, endrin
breakdown, column performance {primary column), and chromatographic
performance. LPC sample components and performance criteria are
listed in Table 7. Inability to demonstrate acceptable instrument
performance indicates the need for reevaluation of the instrument
system. The sensitivity requirement is based on the Estimated
Detection Limits (EDLs) published in this method. If laboratory
EDLs differ from those listed in this method, concentrations of the
LPC standard must be adjusted to be compatible with the laboratory
EDLs. If endrin breakdown exceeds 20 %, the problem can most likely
be solved by performing routine maintenance on the injection port
including replacing the injection port sleeve, and all associated
seals and septa. If column or chromatographic performance criteria
cannot be met, new columns may need to be installed, column flows
corrected, or modifications adapted to the oven temperature program.
During early method development work, significant chromatographic
and column performance problems were observed while using a DB-1
column which had been used for several years for drinking water
extract analysis. By installing a new DB-1 column, these
performance problems were overcome. If the columns to be used for
this method have been used for several years or have had extended
use with extracts from harsh sample matrices (i.e. wastewater,
acidified sample extracts, hazardous waste samples) it may be
difficult to meet the criteria established for this LPC standard and
column replacement may be the best alternative.
9.3 LABORATORY REAGENT BLANKS (LRB). Before processing any samples, the
analyst must analyze an LRB to demonstrate that all glassware and
reagent interferences are under control. In addition, each time a
set of samples is extracted or reagents are changed, a LRB must be
analyzed. If the LRB produces a peak within the retention time
window of any analyte (Sect. 12.2) preventing the quantitation of
551.1-19
-------
that analyte, determine the source of the contamination and
•eliminate the interference before processing samples. LRB samples
must'contain the appropriate buffer for the target analytes
(buffered/NH4GL dechlorinated and/or buffered/Na2S03 dechlorinated
reagent water).
9.3.1 Prepare the two LRBs in the appropriate buffered/
dechlorinated reagent water. Add 50 ^L of surrogate primary
dilution standard (Sect. 7.4.1) to each blank and follow the
procedure outlined in Sect. 11.2.
9.4 INITIAL DEMONSTRATION OF CAPABILITY (IDC)
9.4.1 Preparation of the IDC Laboratory Fortified Blank (LFB).
Select a concentration for each of the target analyte which
is approximately 50 times the EDL or close to the expected
levels observed in field samples. Concentrations near
' analyte levels in Table 3.A are recommended. Prepare a LFB
by adding the appropriate concentration of the primary
dilution standard (Sect. 7.4) to each of four to seven 50 ml .
aliquots of buffered/NH4Cl dechlorinated reagent water.
Separate Na,SO, preserved matrices need not be analyzed
(Sect. 9.4.1.1). Analyze the aliquots according to the
method beginning in Section 11.
9.4.1.1 Chloral hydrate is included in the buffered/NH4Cl
dechlorinated reagent water, containing all the
other target analytes since no matrix induced
recovery problems have been found from reagent water
preserved with NH4C1.
9.4.2 Following procedural calibration standard analysis and
subsequent instrument calibration, analyze a set of at least
seven IOC samples and calculate the mean percent recovery (R)
and the relative standard deviation of this recovery (RSD).
The percent recovery is determined as the ratio of the
(measured concentration to the actual fortified concentration.
.t For each analyte, the mean recovery value must fall within
the range of 80% to 120% and the RSO must not exceed 15 %.
For those compounds that meet these criteria, performance is
considered acceptable, and sample analysis may begin. For
those compounds that fail these criteria, this procedure must
be repeated using eight fresh samples until satisfactory
performance has been demonstrated.
9.4.3 The initial demonstration of capability is used primarily to
preclude a laboratory from analyzing and reporting unknown
samples without obtaining some experience with an unfamiliar
method. It is expected that as laboratory personnel gain
experience with this method, the quality of data will improve
beyond those specified in Sect. 9.4.2.
551.1-20
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9.4.4 METHOD DETECTION LIMITS (MDL). Prior to the analysis of any
field samples the method detection limits must be determined.
Initially, estimate the concentration of an analyte which
would yield a peak equal to 5 times the baseline noise and
drift. Prepare a primary dilution standard with analyte
concentrations at 1000 times this level in acetone (or
methanol for chloral hydrate).
9.4.4.1 Prepare a 500 ml aliquot of buffered/ammonium
chloride dechlorinated reagent water. Fill a
minimum of seven replicate, 60-mL vials with 50 mL
of the buffered/dechlorinated (NH4C1) reagent water.
9.4.4.2 Fortify the 50 ml buffered/dechlorinated (NH4C1)
reagent water with 50 //L of both the MDL concentrate
prepared in acetone and the chloral hydrate MDL
concentrate in methanol. Separate preparation of a
reagent water containing Na,S03 as the
dechlorinating agent for chloral hydrate MDL
determination is not necessary. (See Sect. 9.4.1.1)
9.4.4.3 Extract and analyze these samples as outlined in
Section 11. MDL determination can then be performed
as discussed in Sect. 13.1.
9.5 LABORATORY FORTIFIED BLANK (LFB). Since this method utilizes
procedural calibration standards, which are fortified reagent water,
there is no difference between the LFB and the continuing
calibration check standard. Consequently, there is not a
requirement for the analysis of an LFB. However, the criteria
established for the continuing calibration check standard (Sect.
10.4) should be evaluated as the LFB.
9.6 LABORATORY FORTIFIED SAMPLE MATRIX (LFM). The laboratory must add
known concentrations of analytes to a minimum of 10% of the routine
samples or one fortified sample per sample set, whichever is
greater, for both NH4C1 and Na2S03 dechlorinated sample matrices.
The concentrations should be equal to or greater than the background
concentrations in the sample selected for fortification. Over time,
samples from all routine sample sources should be fortified. By
fortifying sample matrices and calculating analyte recoveries, any
matrix induced analyte bias is evaluated. When an analyte recovery
falls outside the acceptance criteria outlined below, a bias is
concluded and that analyte for that matrix is reported to the data
user as suspect.
9.6.1 First, follow the procedure outlined in Sect. 11.1
9.6.2 Next, prepare the LFM by adding 50 //L of an acetone based
standard solution into the remaining 50 mL of the buffered/
NH4C1 dechlorinated sample matrix in the vial in which it was
551.1-21
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sampled. This sample vial will have had the required amount
of aqueous sample removed as specified in Sect. 11.1.2. Add
50 /Jl of surrogate primary dilution standard (Sect. 7.4.1)
and follow procedure outlined in Sections 11 and 12.
9.6.3 When chloral hydrate is being determined, prepare the LFM by
adding 50 fjl of a methanol based chloral hydrate standard
solution into 50 ml of the buffered/Na2S03 dechlorinated
sample matrix in the vial in which it was sampled. Add 50 jj
of surrogate primary dilution standard (Sect. 7.4.1) and
follow procedure outlined in Sections 11 and 12.
9.6.4 Calculate the percent recovery, R, of the concentration for
each analyte, after correcting the total measured
concentration, A, from the fortified sample for the
background concentration, B, measured in the unfortified
sample, i.e.:
R = 100 (A - B) / C,
where C is the fortifying concentration. The recoveries of
all analytes being determined must fall between 75 % and 125
% and the recoveries of at least 90% of these analytes must
fall between 80 % and 120 %. This criteria is applicable to
both external and internal standard calibrated quantitation.
9.6.5 If a recovery falls outside of this acceptable range, a
matrix induced bias can be assumed for the respective analyte
and the data for that analyte in that sample matrix must be
reported to the data user as suspect.
9.6.6 If the unfortified matrix has analyte concentrations equal to
or greater than the concentration fortified, a duplicate
sample vial needs to be fortified at a higher concentration.
If no such sample is available the recovery data for the LFM
. sample should not be reported for this analyte to the data
user.
9.7 FIELD DUPLICATES (FD1 and FD2). The laboratory must analyze a field
sample duplicate for a minimum of 10% of the total number of field
samples or at least one field sample duplicate per sample set,
whichever is greater. Duplicate results must not reflect a relative
percent difference (RPD as defined below) greater than 25% for any
one analyte and the RPD for 90% of the analytes being determined
must be less than 20%.
RPD
(FD1 - FD2)
((FD1 + FD2) / 2)
X 100
551.1-22
-------
where F01 and FD2 represent the quantified concentration on an
Individual analyte for the initial and duplicate field sample
analysis, respectively. If this criteria is not met the analysis
must be repeated. Upon repeated failure, the sampling must be
repeated or the analyte out of control must be reported as suspect
to the data user.
9.8 ASSESSING SURROGATE RECOVERY
9.8.1 The surrogate analyte is fortified into the aqueous portion
of all calibration standards, quality control samples and
field samples. By monitoring the surrogate response, the
analyst generates useful quality control information from
extraction precision through quantitative analysis.
Deviations in surrogate recovery may indicate an extraction
problem. If using external standard calibration the
surrogate retention time functions as a reference for
identification of target analytes.
9.8.2 Using the mean surrogate response from the calibration
standard analyses (Cal-), determine the surrogate percent
recovery (%RECS) in all calibration standards, LFBs, and
LFMs, and field samples. This recovery is calculated by
dividing the surrogate response from the sample (SamSR) by
the mean response from the initial calibration standards
(Sect. 10.2 or 10.3) and multiplying by 100, as shown below.
% RECe
Sam
SR
x 100
Cal
SR
9.8.3
Recoveries must fall within the range of 80% to 120%. If a
sample provides a recovery outside of this range, the extract
must be reanalyzed. If upon reanalysis, the recovery
continues to fall outside the acceptable range a fresh sample
should be extracted and analyzed. If this is not possible
the data for all the analytes from this sample should be
reported to the data user as suspect due to surrogate
recovery outside acceptable limits.
If consecutive samples fail the surrogate response acceptance
criterion, immediately analyze a continuing calibration
standard.
9.8.3.1 If the continuing calibration standard provides a
recovery within the acceptable range of 80% to 120%,
then follow procedures itemized in Sect. 9.8.2 for
each sample failing the surrogate response
criterion.
9.8.3.2 If the check standard provides a surrogate recovery
which falls outside the acceptable range or fails
551.1-23
-------
the acceptance criteria specified in Sect. 10.4 for
the target analytes, then the analyst must
recalibrate, as specified in Sect. 10.
9.9 ASSESSING THE INTERNAL STANDARD (IS)
9.9.1 When using the internal standard calibration procedure, the
analyst must monitor the internal standard response (peak
area or peak height) of all samples during each analysis day.
The internal standard response should not deviate from mean
internal standard response of the past five continuing
calibration standards by more than 20%.
9.9.2 If > 20% deviation occurs with an individual extract,
optimize instrument performance and inject a second aliquot
of that extract.
9.9.2.1 If the reinjected aliquot produces an acceptable
internal standard response, report results for that
aliquot.
9.9.2.2 If a deviation of greater than 20% is obtained for
the reinjected extract, analysis of a calibration
check standard must be performed (Sect. 10.4).
9.9.3 If consecutive samples fail this IS response acceptance
criterion, immediately analyze a calibration check standard.
9.9.3.1 If the check standard provides a response factor
(RF) within 20% of the predicted value for the
internal standard and the criteria for all the
target analytes as specified in Sect. .10.4 is met,
,9- the previous sample(s) failing the IS response
criteria need to be reextracted provided the sample
is still available. In the event that reextraction
is not possible, report results obtained from the
reinjected extract (Sect 9.9.2) but annotate as
suspect due to internal standard recovery being
outside acceptable limits.
9.9.3.2 If the check standard provides a response factor
which deviates more than 20% of the predicted value
for the internal standard or the criteria for the
target analytes, as specified in Sect 10.4 are not
met, then the analyst must recalibrate, as specified
in Sect. 10.3 and all samples analyzed since the
previous calibration check standard need to be
reanalyzed.
9.10 CONFIRMATION COLUMN ANALYSIS. If a positive result is observed on
the primary column, a confirmation analysis should be performed
using either the confirmation column or by GC/MS.
551.1-24
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9.11 The laboratory may adapt 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 reagent blanks may be used to
assess contamination of samples under site conditions,
transportation and storage.
9.12 Quality control samples (QCS) from an outside source, as defined in
Sect. 3.12, should be analyzed at least quarterly.
10. CALIBRATION AND STANDARDIZATION
10.1 PREPARATION OF CALIBRATION STANDARDS
10.1.1 Five calibration standards are required. One should contain
the analytes at a concentration near to but greater than the
method detection limit (Table 2) for each compound; the
others should be evenly distributed throughout the
concentration range expected in samples or define the working
range of the detector. Guidance on the number of standards
is as follows: A minimum of three calibration standards are
required to calibrate a range of a factor of 20 in
concentration. For a factor of 50 use at least four
standards, and for a factor of 100 at least five standards.
For example, if the MDL is 0.1 ^g/L, and a sample
concentrations are expected to range from 1.0 p.g/1 to 10.0
M9/L, aqueous standards should be prepared at 0.20 M9/U 0-80
2.0 M9/U 5.0 M9/U and 15.0 M9/L.
10.1.2 As a means of eliminating any matrix effects due to the use
of the phosphate buffer and dechlorinating agents, the
procedural calibration standards are prepared in reagent
water which has been buffered to pH 4.8 - 5.5 and
dechlorinated with ammonium chloride. To prepare this
buffered/dechlorinated reagent water, add 5.0 g of phosphate
buffer/dechlorinating agent (Sect 7.1.7.4, ammonium chloride
type) to 500 mL of reagent water (Sect. 7.2).
10.1.3 Next, add 25 pi of the desired concentration primary dilution
standards (acetone and methanol based, Sect. 7.4) to a 50 ml
aliquot of the buffered/dechlorinated reagent water in a 60-
mL vial. Use a 50-/iL micro syringe and rapidly inject 25 jiL
of the standard into the middle point of the water volume.
Remove the needle as quickly as possible after injection.
Next, add 50 juL of the surrogate standard solution (Sect.
7.4.1) in the same manner. Mix by slowly and carefully
inverting the sample vial two times with minimal sample
agitation. Aqueous standards must be prepared fresh daily
and extracted immediately after preparation (Section 11.2).
10.1.3.1 By including chloral hydrate into the total NH«C1
analyte matrix, a separate calibration standard
analysis for Na2S03 preserved reagent water
fortified with chloral hydrate is avoided. Chloral
551.1-25
-------
hydrate is included in the buffered/NH4Cl
dechlorinated reagent water, containing all the
other target analytes since no matrix induced
recovery problems have been found from reagent water
preserved with NH«C1. Warning! Do not attempt to
analyze chloral hydrate in field samples preserved
with NH4C1, low recoveries may result due to matrix
effects.
10.1.4 CAUTION - DO NOT prepare procedural calibration standards in
a volumetric flask and transfer the sample to an extraction
vial either directly for weight determination of volume or
into a graduated cylinder with a subsequent additional
transfer into the extraction vial. Volatility experiments
reflected as much as a 30 % loss in volatile low molecular
weight analytes following such transfers. All fortified
samples and field samples must be extracted in the vial or
bottle in which they were fortified and collected.
10.2 EXTERNAL STANDARD CALIBRATION PROCEDURE
10.2.1 Extract and analyze each calibration standard according to
Section 11 and tabulate peak height or area response versu's
the concentration of the standard. The results are used to
prepare a calibration curve for each compound by plotting the
peak height or area response versus the concentration. This
curve can be defined as either first or second order.
Alternatively, if the ratio of response to concentration
{response factor) is constant over the working range (< 10%
relative standard deviation,[RSD]), linearity through the
origin can be assumed, and the average ratio or calibration
factor can be used in place of a calibration curve.
10.2.2 Surrogate analyte recoveries must be verified as detailed in
Sections 9.8.
10.3 INTERNAL STANDARD (IS) CALIBRATION PROCEDURE
10.3.1 Extract each calibration standard according to Section 11.
Remove a 1.00 mL portion of the MTBE or pentane extract from
the sample extraction vial and place this into a 2.0-mL
autosampler vial. To this extract, add the 10 p.1 of the
internal standard primary dilution standard, cap the vial and
analyze. Following analysis, tabulate peak height or area
responses against concentration for each compound and the
internal standard. Calculate relative response factor (RRF)
for each compound using Equation 1.
551.1-26
-------
Equation 1
RRF
iAsl_LCisl
(Ais} (Ct)
where
= Response for the analyte to be measured
= Response for the internal standard
= Concentration of the internal standard (fig/I)
= Concentration of the analyte to be measured
If RF value over the working range is constant (< 10% RSO),
the average RF can be used for calculations. Alternatively,
the results can be used to plot a calibration curve of
response versus analyte ratios, As/Ajs vs. Cs.
10.4 CONTINUING CALIBRATION CHECK STANDARD •
10.4.1 Preceding each analysis set, after every tenth sample
analysis and after the final sample analysis, a calibration
standard should be analyzed as a continuing calibration
check. These check standards should be at two different
concentration levels to verify the calibration curve. This
criteria is applicable to both external and internal standard
calibrated quantitation. Surrogate and internal standard
recoveries must be verified as detailed in Sections 9.8 and
9.9, respectively.
10.4.2 In order for the calibration to be considered valid, analyte
recoveries for the continuing calibration check standard must
fall between 75 % and 125 % for all the target analytes. The
recoveries of at least 90% of the analytes determined must
fall between 80% and 120%
10.4.3 If this criteria cannot be met, the continuing calibration
check standard is reanalyzed in order to determine if the
response deviations observed from the initial analysis are
repeated. If this criteria still cannot be met then the
instrument is considered out of calibration for those
specific analytes beyond the acceptance range. The
instrument needs to be recalibrated and the previous samples
reanalyzed or those analytes out of acceptable range should
be reported as suspect to the data user for all the
previously analyzed samples.
11. PROCEDURE
' 11.1 SAMPLE PREPARATION
11.1.1 Remove samples from storage and allow them to equilibrate to
room temperature.
551.1-27
-------
11.1.2 Remove the vial caps. Remove a 10 ml volume of the sample.
Check the pH of this 10 ml aliquot to verify that it is
within a pH range of 4.5 and 5.5. If the pH is out of this
range a new sample must be collected. Replace the vial caps
and weigh the containers with contents to the nearest 0.1 g
and record these weights for subsequent sample volume
determination. (See Sect. 11.2.4 for continuation of
weighing and calculation of true volume). Alternatively, the
sample vials may be precalibrated by weighing in 50 ml of
water and scoring the meniscus on the bottle. This will
eliminate the gravimetric step above and in Sect. 11.2.4.
11.1.3 Inject 50pL of the surrogate analyte fortification solution
(Sect. 7,4.1) into the sample. The aqueous concentration of
surrogate analyte must be the same as that used in preparing
calibration standards (Sect. 9.1.3). Mix by slowly and
carefully inverting the sample vial two times with minimal
sample agitation.
11.2 SAMPLE EXTRACTION
11.2.1 WITH MTBE AS EXTRACTION SOLVENT
11.2.1.1 After addition of the surrogate (Sect 11.1.3) add
exactly 3.0 roL of MTBE with a type A, TD, transfer
or automatic dispensing pipet.
11.2.1.2 Add 10 g NaCl or 20 g Na2SOA to the sample vial.
(See Section 13.7 for an important notice concerning
the use of NaCl when analyzing for DBFs.) Recap and
extract the NaCl or Na2SO, /MTBE/sample mixture by
vigorously and consistently shaking the vial by hand
for 4 min. Invert the vial and allow the water and
MTBE phases to separate (approx. 2 min).
If a series of samples are being prepared for
extraction using Na^SO^, immediately after the
addition of the Na2S04, the sample should be
recapped, agitated and placed in a secure horizontal
position with the undissolved Na,SO, distributed
along the length of the vial. If the vial is left
in a vertical position, while additional samples
have solvent and salt added, the Na2S04 will
solidify in the bottom of the vial and it will not
dissolve during sample extraction.
NOTE: Previous versions of this method call for the
addition of the salt by "shaking the vial
vigorously" before the MTBE has been added. Please
make a note that this procedural order has been
changed in an effort to minimize volatile analyte
losses.
551.1-28
-------
11.2.1.3 By using a disposable Pasteur pipet (Sect. 6.2),
transfer a portion of the solvent phase from the 60-
ml vial to an autosampler vial (Sect. 6.2). Be
certain no water has carried over onto the bottom of
the autosampler vial. If a dual phase appears in
the autosampler vial, the bottom layer can be easily
removed and discarded by using a Pasteur pipet. The
remaining MTBE phase may be transferred to a second
autosampler vial as a backup extract or for separate
confirmation analysis. Approximately 2.5 ml of the
solvent phase can be conveniently transferred from
the original 3 ml volume.
11.2.1.3.1 If using an internal standard
quantitation, the extract transfer into
the autosampler vial must be performed
in a quantitative manner. This may be
done using a 1.00 ml syringe or a 2.00-
ml_ graduated disposable pipet to
accurately transfer 1.00 ml of sample
extract to the autosampler vial where 10
fjl of internal standard primary dilution
standard (Sect. 7.4.2) solution can be
added.
11.2.2 WITH PENTANE AS EXTRACTION SOLVENT
11.2.2.1 After addition of the surrogate (Sect 11.1.3) add
exactly 5.0 ml of pentane with a type A, TO,
transfer or automatic dispensing pipet.
11.2.2.2 Add 20 g Na2S04 to the sample vial. Recap and
extract the Na2S04/pentane/sample mixture by
vigorously and consistently shaking the vial by hand
for 4 min. Invert the vial and allow the water and
pentane phases to separate (approx. 2 min). NOTE:
Previous versions of this method call for the
addition of NaCl by "shaking the vial vigorously"
before the pentane has been added. Please make a
note that this procedural order has been changed in
an effort to minimize volatile analyte losses. If a
series of samples are being prepared for extraction,
immediately after the addition of the Na2S04, the
sample should be recapped, agitated and placed in a
secure horizontal position with the undissolved
Na2S04 distributed along the length of the vial. If
the vial is left in a vertical position, while
additional samples have solvent and salt added, the
Na2SO, will solidify in the bottom of the vial and
it will not dissolve during sample extraction.
551.1-29
-------
11.2.2.3 Using a disposable Pasteur pipet, transfer a portion
of the solvent phase from the 60-mL vial to an
autosampler vial. Be certain no water has carried
over onto the bottom of the autosampler vial. If a
dual phase appears in the autosampler vial, the
bottom layer can be easily removed and discarded
using a Pasteur pipet. The remaining pentane phase
may be transferred to a second autosampler vial as a
backup extract or for separate confirmation
analysis.
11.2.2.3.1 The extract transfer into the
autosampler vial must be performed in a
quantitative manner. This may be done
using a 1.00-mL syringe or a 2.00-mL
graduated disposable pipet to accurately
transfer 1.00 ml of sample extract to
the autosampler vial where 10 //L of
internal standard primary dilution
standard (Sect. 7.4.2) solution can be
added.
11.2.3 Discard the remaining contents of the sample vial. Shake off
the last few drops with short, brisk wrist movements.
11.2.4 Reweigh the empty vial with the original cap and calculate
the net weight of sample by difference to the nearest 0.1 g
(Sect. 11.1.2 minus Sect. 11.2.4). This net weight (in
grams) is equivalent to the volume of water (in ml)
extracted, Vs.
11.2.5 The sample extract may be stored in a freezer (<-10°C) for a
maximum of fourteen days before chromatographic analysis but
no more than 24 hours at room temperature (i.e. on an
autosampler rack). Due to the volatility of the extraction
solvent, if the septum on a vial has been pierced, the crimp
top or screw cap septum needs to be replaced immediately or
the extract cannot be reanalyzed at a later time.
11.3 SAMPLE ANALYSIS
11.3.1 The recommended GC operating conditions are described in
6.9.2.1 and 6.9.2.2 along with recommended primary and
confirmation columns. Retention data for the primary and
confirmation columns are given in Table 1.
11.3.2 Inject 2 (tl of the sample extract and record the resulting
peak response. For optimum performance and precision, an
autosampler for sample injection and a data system for signal
processing are strongly recommended.
551.1-30
-------
12. DATA ANALYSIS AND CALCULATIONS
12.1 Identify sample components by comparison of retention times to
retention data from the calibration standard analysis. If the
retention time of an unknown compound corresponds, within limits
(Sect. 12.2), to the retention time of a standard compound, then
identification is considered positive.
12.2 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. Use the initial demonstration of capability
retention time data as an initial means of determining acceptable
retention time windows. Throughout the development of this method a
retention time window of 1.0 % of the total analyte retention time
was used.
12.3 Identification requires expert judgment when sample components are
not resolved chromatographically, that is, when GC peaks obviously
represent more than one sample component (i.e., broadened peak with
shoulder(s) or valley between two or more maxima). Whenever doubt
exists over the identification of a peak in a chromatogram,
confirmation is suggested by the use of a dissimilar column or by
GC-MS when sufficient concentrations of analytes are present.
12.4 If the peak response exceeds the linear range of the calibration
curve, the final extract should be diluted with the appropriate
extraction solvent and reanalyzed. The analyst is not permitted to
extrapolate beyond the concentration range of the calibration curve.
12.5 Calculate the uncorrected concentrations (C;) of each analyte in the
sample from the response factors or calibration curves generated in
Sect. 10.2.1 or 10.3.1. do not use the daily calibration check
standard to calculate amounts of method analytes in samples.
12.6 Calculate the corrected sample concentration as:
Concentration, (ig/L = Cf x 50 ,
Vs
where the sample volume, Vs in ml, is equivalent to the net sample
weight in grams determined in Sect. 11.1.2 and Sect. 11.2.4.
13. METHOD PERFORMANCE
13.1 In a single laboratory, analyte recoveries from reagent water with
MTBE as the extracting solvent, were determined at three
concentration levels, Tables 2A through 4B. Results from the lowest
fortified level were used to determine the analyte MOLs (11) listed
551.1-31
-------
In Table 2. These MDLs along with the estimated detection limit
(EDL) were determined in the following manner. EDLs are provided
for informational purposes.
13.1.1 For each analyte, calculate the mean concentration and the
standard deviation of this mean between the seven replicates.
Multiply the student's t-value at 99% confidence and n-1
degrees of freedom (3.143 for seven replicates) by this
standard deviation to yield a statistical estimate of the
detection limit. This estimate is the MDL.
13.1.2 Since the statistical estimate is based on the precision of
the analysis, an additional estimate of detection can be
determined based upon the noise and drift of the baseline as
well as precision. This estimate, known as the "EDL" is
defined as either the MDL or a level of compound in a sample
yielding a peak in the final extract with a signal to noise
(S/N) ratio of approximately 5, whichever is greater.
13.1.3 These MDL determinations were conducted on both the primary
(DB-1) and the confirmation (Rtx-1301) columns and are
presented in Tables 2.A. through 2.D.
13.2 Analyte recoveries were also determined for reagent water with
pentane as the extracting solvent. Two concentration levels were
studied and the results are presented in Tables 8 and 9. Results
from the lowest fortified level were used to determine the analyte
MDLs (11) listed in Table 8. These MDLs along with the estimated
detection limit (EDL) were determined in a manner analogous to that
described in Sect. 13.1.1 through 13.1.2.
13.3 In a single laboratory, method precision and accuracy were evaluated
using analyte recoveries from replicate buffered/dechlorinated (both
NH4C1 and Na2S03) matrices with MTBE as the extracting solvent. The
matrices studied included; fulvic acid fortified reagent water and
ground water displaying a high CaCO, content. The results for these
are presented in Tables 3.A. through 6.B. These matrices were
fortified using outside source analyte solutions (except for the
pesticides and herbicides) to assess accuracy and eight replicate
analyses were conducted to assess precision.
13.4 Holding time studies were conducted for buffered/dechlorinated
reagent water and tap water. Holding studies were also conducted on
MTBE sample extracts from these two matrices. Results indicated
that analytes were stable in these water matrices stored at 4°C.
13.5 MTBE and pentane extracts holding studies indicated the analytes
were stable for 14 days when stored in a freezer at <-10°C.
13.6 Chromatograms of a fortified, buffered/NH4Cl dechlorinated reagent
water extract are presented as Figures 1 through 3. In the
chromatograms of Figures 1 and 2, the elution of the method analytes
551.1-32
-------
from a MTBE extract can be seen on the primary DB-1 column and the
confirmation Rtx-1301 column, respectively. Figure 3 shows the
elution of the method analytes from a pentane extract, using a
modified temperature program, on the primary DB-1 column. Analyte
numerical peak identification, retention time and fortified
concentrations are presented for information purposes only in Tables
10, 11 and 12 for Figures 1, 2 and 3, respectively.
13.7 IMPORTANT NOTICE: All demonstration data presented in Section 17
using MTBE as the extracting solvent, was obtained using NaCl as the
salt. A recent report (19) indicated elevated recoveries (via
synthesis) of some brominated DBPs when NaCl was used in the
extraction process, due to the inevitable presence of bromide
impurities in the NaCl. This phenomenon has been confirmed by the
authors of this method in samples from chlorinated water systems
that were not extracted immediately after the NaCl was added.
Significant effects can be seen if extraction is delayed for as
little as 15 minutes after the addition of the NaCl. For this
reason, the use of Na,SO, is strongly recommended over NaCl for MTBE
extraction of DBPs. Although less method validation data have been
obtained for the Na2S04 option, sufficient data have been collected
to indicate that it is equivalent or superior to NaCl in salting out
the method analytes, and has no observed negative effect on
precision or accuracy.
14. POLLUTION PREVENTION
14.1 This method is a micro-extraction procedure which uses a minimal
amount of extraction solvent per sample. This microextraction
procedure reduces the hazards involved with handling large volumes
of potentially harmful organic solvents needed for conventional
liquid-liquid extractions.
14.2 For information about pollution prevention that may be applicable to
laboratory operations, consult "Less is Better: Laboratory Chemical
Management for Waste Reduction", available from the American
Chemical Society's Department of Government Relations and Science
Policy, 1155 16th Street N.W., Washington, D.C. 20036.
15. WASTE MANAGEMENT
15.1 Due to the nature of this method, there is little need for waste
management. No large volumes of solvents or hazardous chemicals are
used. The matrices of concern are finished drinking water or source
water. However, the Agency requires that laboratory waste
management practices be conducted consistent with all applicable
rules and regulations, and that laboratories protect the air, water,
and land by minimizing and controlling all releases from fume hoods
and bench operations. Also, compliance is required with any sewage
discharge permits and regulations, particularly the hazardous waste
identification rules and land disposal restrictions. For further
information on waste management, consult "The Waste Management
551.1-33
-------
Manual for Laboratory Personnel," also available from the American
Chemical Society at the address in Sect. 14.2.
16. REFERENCES
1. Glaze, W.W., Lin, C.C., "Optimization of Liquid-Liquid Extraction
Methods for Analysis of Organics in Water", EPA-600/S4-83-052, U.S.
Environmental Protection Agency, January 1984.
2. Richard, J.J., Junk, G.A., "Liquid Extraction for Rapid
Determination of Halomethanes in Water," Journal AWWA. 69, 62, 1977.
3. Reding, R., P.S. Fair, C.J. Shipp, and H.J. Brass, "Measurement of
Dihaloacetonitriles and Chloropicrin in Drinking Water",
" Disinfection Byproducts: Current Perspectives ", AWWA, Denver,CO
1989.
4. Hodgeson, J.W., Cohen, A.L. and Collins, J. P., "Analytical Methods
for Measuring Organic Chlorination Byproducts" Proceedings Water
Quality Technology Conference (WQTC-16), St. Louis, MO, Nov. 13-17,
1988, American Water Works Association, Denver, CO, pp. 981-1001.
5. 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.
6. Fair, P.S., Barth, R.C., Flesch, J.J. and Brass, H., "Measurement of
Disinfection Byproducts in Chlorinated Drinking Water," Proceedings
Water Quality Technology Conference (WQTC 15), Baltimore, MD, None.
15-20, 1987, American Water Works Association, Denver, CO, pp 339-
353
7. Trehy, M.L. and Bieber, T.I. (1981). In " Advances in the
Identification and Analysis of Organic Pollutants in Water II" (L.H.
Keith, ed.) pp 941-975. Ann Arbor Sci. Publ,, Ann Arbor, Michigan.
8. Oliver, B.G., "Dihaloacetonitriles in Drinking Water: Algae and
Fulvic Acid as Precursors," Environ. Sci. Techno!. 17, 80, 1983.
9. Krasner, S.W., Sclimenti, M.J. and Hwang, C.J., "Experience with
Implementing a Laboratory Program to Sample and Analyze for
Disinfection By-products in a National Study," Disinfection By-
products: Current Perspectives. AWWA, Denver, CO, 1989.
10. Munch, J. W., "Method 525.2-Determination of Organic Compounds in
Drinking Water by Liquid-Solid Extraction and Capillary Column
Chromatography/ Mass Spectroraetry" in Methods for the Determination
of Organic Compounds in Drinking Water; Supplement 3 (1995).
USEPA, National Exposure Research Laboratory, Cincinnati, Ohio
45268.
551.1-34
-------
11. Munch, J.W., "Method 524.2- Measurement of Purgeable Organic
Compounds In Water by Capillary Column Gas Chromatography/ Mass
Spectrometry" in Methods for the Determination of Organic Compounds
in Drinking Water: Supplement 3 H995K USEPA, National Exposure
Research Laboratory, Cincinnati, Ohio 45268.
12. Glaser, J.A., Foerst, D.L., McKee, G.D., Quave, S.A. and Budde, W.L.
"Trace Analysis for Wastewaters", Environ. Sci. Techno!.. I_5, 1426,
1981.
13. ASTM Annual Book of Standards, Part 11, Volume 11.02, D3694-82,
"Standard Practice for Preparation of Sample Containers and for
Preservation," American Society for Testing and Materials,
Philadelphia, PA, 1986.
14. Bellar, T.A., Stemmer, P., Lichtenburg, J.J., "Evaluation of
Capillary Systems for the Analysis of Environmental Extracts," EPA-
600/S4-84-004, March 1984.
15. "Carcinogens-Working with Carcinogens", Publication No. 77-206,
Department of Health, Education, and Welfare, Public Health Service,
Center for Disease Control, National Institute of Occupational
Safety and Health, Atlanta, Georgia, August 1977.
16. "OSHA Safety and Health Standards, General Industry", (29CFR1910),
OSHA 2206, Occupational Safety and Health Administration,
Washington, D.C. Revised January 1976.
17. "Safety in Academic Chemistry Laboratories", 3rd Edition, American
Chemical Society Publication, Committee on Chemical Safety,
Washington, D.C., 1979.
18. Cole, S., Henderson, D. "Atrazine and Simazine - Product Redesign
improves Stability". The Reporter, Volume 13, No. 6, 1994, pg 12.
Trade publication from Supelco, Inc.
t
19. Xie, Yuefeng, "Effects of Sodium Chloride on DBP Analytical
Results," Extended Abstract, Division of Environmental Chemistry,
American Chemical Society Annual Conference, Chicago, IL, Aug. 21-
26, 1995.
551.1-35
-------
TABLE 1. RETENTION TIME DATA USING NTBE
Column Aa
Retention Time
ANALYTE minutes
Chloroform
1,1, 1-Trichloroethane
Carbon Tetrachloride
Tr i chl oroaceton i tri 1 e
Dichl Oroacetoni tri 1 e
Bromod i chl oromethane
Trichloroethylene
Chloral Hydrate
1 , 1-Di chl oro-2-Propanone
1,1, 2-Tri chl oroethane
Chloropicrin
Dibromochl oromethane
Bromochl oroacetoni tri 1 e
1,2-Dibromoethane (EDB)
Tetrachl oroethyl ene
1,1, 1-Trichloropropanone
Bromoform
Di bromoaceton i tr i 1 e
1,2, 3-Tr i chl oropropane
l,2-Dibromo-3-chloropropane (DBCP)
Hexachl orocycl opent ad i ene
Trifluralin
Simazine
Atrazine
Hexachl orobenzene
Lindane (gamma-BHC)
Metribuzin
Bromacil
7.04
8.64
9.94
10.39
12.01
12.42
12.61
13.41
14.96
19.91
23.10
23.69
24.03
24.56
26.24
27.55
29.17
29.42
30.40
35.28
40.33
45.17
46.27
46.55
47.39
47.95
50.25
52.09
Column Bb
Retention Time
minutes
7.73
7.99
8.36
10.35
25.21
15.28
11.96
NR c
20.50
25.01
23.69
26.32
29.86
26.46
24.77
28.47
30.36
32.77
31.73
36.11
39.53
45.43
48.56d
48.56d
46.47
49.68
53.92
59.60
551.1-36
-------
TABLE 1. RETENTION TIME DATA USING MTBE (cont'd)
Column Aa
Retention Time
Column Bb
Retention Time
ANALYTE
Alachlor
Cyanazine
Heptachlor
Metolachlor
Heptachlor Epoxide
Endrin
Endrin Aldehyde
Endrin Ketone
Methoxychlor
Surrogate:
minutes
52.25
53.43
53.72
55.44
58.42
64.15
65.46
72.33
73.53
36.35
minutes
54.38
59.89
53.15
57.07
59.05
65.24
71.56
81.28
76.73
36.28
Decafluorobiphenyl
31.00
31.30
Internal Standard:
Bromofluorobenzene
(a) Column A - 0.25 ram ID x 30 m fused silica capillary with chemically
bonded methyl polysiloxane phase (J&W, DB-1, 1.0 (tm film
thickness or equivalent). The linear velocity of the
helium carrier is established at 25 cm/sec at 35°C.
The column oven is temperature programmed as follows:
[1] HOLD at 35°C for 22 min
[2] INCREASE to 145°C at 10°C/min and hold at 145°C for 2 min
[3] INCREASE to 225°C at 20°C/min and hold at 225°C for 15 min
[4] INCREASE to 260°C at 10°C/min and hold at 260°C for 30
min. or until all expected compounds have eluted.
Injector temperature: 200°C
Detector temperature:. 290°C
(b) Column B -
0.25 mm ID x 30 m with chemically bonded 6 %
cyanopropylphenyl/94 % dimethyl polysiloxane phase
(Restek, Rtx-1301, 1.0 0m film thickness or equivalent).
The linear velocity of the helium carrier gas is
established at 25 cm/sec at 35°C.
The column oven is temperature programmed exactly as indicated
for column A, above. The same temperature program is utilized
to allow for simultaneous confirmation analysis.
(c)
There is no retention time for this analyte since it does not separate
into a discreet peak on the Rtx-1301.
(d) Atrazine and simazine coelute on the confirmation column.
551.1-37
-------
TABLE 2.A.
NHC1 PRESERVED
METHOD DETECTION LIMIT USING MTBE
REAGENT WATER ON PRIMARY DB-1 COLUMN
ANALYTE
Alachlor
Atrazlne
Bromacil
Bromochl oroacetonltri 1 e
Bromodi chl oromethane
Bromoforra
Carbon Tetrachloride
Chloral Hydrate
Chloropicrin
Chloroform
Cyanazine
Dlbromoacetoni tri le
01 bromochl oromethane
1 , 2-D1 bromo-3-chl oropropane
1,2-Dibromoethane
Dichloroacetonitrile
1 , 1-Di chl oro-2-propanone
Endrin
Endrln Aldehyde
Endrin Ketone
Heptachlor
Heptachlor Epoxide
Hexachlorobenzene
Hexachl orocycl opentad 1 ene
Lindane (g-BHC)
Methoxychlor
Metolachlor
Metrlbuzin
Simazine
Fort.
Cone.,
//g/L
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.327
.633
.094
.010
.010
.010
.010
.025
.010
.050
.567
.010
.010
.010
.010
.010
.010
.016
.022
.016
.047
0.044
0
0
0
0
0
0
0
.006
.019
.009
.063
.219
.062
.625
Obser.3
Cone. ,
W/L
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.384
.764
.099
.011
.012
.018
.011
.029
.009
.054
.757
.016
.011
.020
.020
.009
.011
.023
.023
.016
.062
.050
.006
.019
.015
.057
.254
.100
.794
Avg,
%Rec.
117
121
105
110
120
180
110
116
90
108
134
160
110
200
200
90
110
144
105
100
132
114
100
100
167
90
116
161
127
%
2
3
10
5
7
8
6
5
7
34
13
12
4
15
12
4
6
2
2
5
43
1
5
31
9
4
3
12
5
RSD
.13
.56
.05
.42
.50
.12
.32
.61
.65
.04
.93
.78
.55
.15
.54
.28
.22
.57
.25
.14
.65
.64
.44
.81
.89
.85
.20
.45
.95
MDLb
//g/L
0
.025
0.082
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.030
.002
.003
.004
.002
.005
.002
.055
.316
.006
.001
.009
.008
.001
.002
.002
.002
.002
.081
.002
.001
.018
.004
.008
.024
.037
.142
EDLC
_j>g/L
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
500
324
055
009
005
006
004
Oil
014
075
685
010
007
009
008
0.005
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
007
Oil
010
020
081
030
006
022
016
046
146
037
431
551.1-38
-------
TABLE 2.A. METHOD DETECTION LIMIT USING MTBE (cont'd)
NH^Cl PRESERVED REAGENT WATER ON PRIMARY DB-1 COLUMN
ANALYTE
Tetrachl oroethyl ene
Tri chl oroacetoni tri 1 e
1 , 1 , 1-Trichloroethane
1,1, 2-Tr i chl oroethane
Tri chl oroethyl ene
1,2, 3-Tr i chl oropropane
1 , 1 , 1-Trichl oro-2-propanone
Trifluralin
Surrogate ===>
Decaf 1 uorobyphenyl
(a) Based upon the analysis
(b) MDL designates the stati
Fort.
Cone. ,
0.
0.
0.
0.
0.
0.
0.
0.
10.
010
010
010
140
010
156
010
022
0
of eight
stically
Obser.8
Cone.,
//g/L
0.012
0.010
0.013
0.124
0.008
0.137
0.027
0.026
10.8
Avg.
%Rec.
120
100
130
89
80
88
270
118
108
replicate MTBE
derived MDL and
5
5
12
3
8
1
20
3
2
RSD
.04
.31
.35
.27
.68
.95
.53
.89
.38
sample
is cal
0
0
0
0
0
0
0
0
MDLb
.002
.002
.005
.012
.002
.008
.016
.003
extracts
culated
0
0
0
0
0
0
0
0
by
EDLC
.004
.004
.005
.040
.008
.028
.016
.010
multiplying the standard deviation of the eight replicates by the
student's t-value (2.998) appropriate for a 99% confidence level and a
standard deviation estimate with n-1 degrees of freedom.
(c) Estimated Detection Limit (EDL) — Defined as either the MDL or a level
of compound in a sample yielding a peak in the final extract with a
signal to noise (S/N) ratio of approximately 5, whichever is greater.
551.1-39
-------
TABLE 2.B. METHOD DETECTION LIMIT USING NTBE
NHAC1 PRESERVED REAGENT WATER
ANALYTE
Alachlor
Bromacil
Bromochl oroacetoni tri 1 e
Bromodichloromethane
Bromoform
Carbon Tetrachloride
Chloropicrin
Chloroform
Cyanazine
Dibromoacetoni tri 1 e
Di bromochl oromethane
l,2-Dibromo-3-chloropropane
1,2-Dibromoethane
Dichl oroacetoni tri 1 e
l,l-Dichloro-2-propanone
Endrin
Endrin Aldehyde
Endrin Ketone
Heptachlor
Heptachlor Epoxide
Hexachlorobenzene
Hexachlorocyclopentadiene
Lindane (g-BHC)
Methoxychlor
Metolachlor
Metribuzin
Simazine/Atrazine
Tetrachl oroethyl ene
Tri chl oroacetoni tri 1 e
Fort.
Cone. ,
//g/L
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
.109
.094
.010
,010
.010
.010
.010
.010
.189
.010
.010
.010
.010
.010
.010
.016
.022
.047
.016
.044
.006
.019
.009
.188
.219
.062
.26 e
.010
.010
ON
CONFIRMATION
Obser."
Cone.,
//g/L
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
.107
.134
.008
.012
.015
.011
NR d
.059
.279
.010
.021
.020
.039
.010
.009
.025
.034
.049
.018
.079
.006
NR
.011
.221 .
.280
.076
.619
.012
.006
Avg.
%Rec.
98
143
80
120
150
110
NR
590
148
100
210
200
390
100
90
156
155
104
113
180
100
NR
122
118
128
123
129
120
60
Rtx-1301 COLUMN
%RSD
1
11
9
4
29
18
.70
.65
.49
.34
.51
.70
HDL"
0
0
0
0
0
0
NR
2
7
4
29
9
6
4
11
4
22
5
3
84
16
.82
.56
.87
.30
.95
.44
.11
.65
.09
.45
.49
.79
.71
.47
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.005
.047
.002
.002
.013
.006
NR
.005
.063
.001
.018
.006
.007
.001
.003
.003
.023
.008
.002
.202
.003
NR
6
3
1
2
2
6
16
.09
.53
.45
.17
.48
.97
.01
0
0
0
0
0
0
0
.002
.023
.012
.005
.121
.002
.003
EDLC
//g/L
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.076
.071
.015
.006
.013
.006
.062
.008
.065
.007
.018
.024
.007
.003
.015
.015
.030
.047
.010
.202
.011
.327 .
.009
.041
.268
.013
.629
.003
.010
551.1-40
-------
TABLE 2.B. METHOD DETECTION LIMIT USING MTBE (cont'd)
NH.C1 PRESERVED REAGENT WATER ON CONFIRMATION Rtx-1301 COLUMN
ANALYTE
1,1, 1-Trichl oroethane
1,1,2-Tri chl oroethane
Trichloroethylene
1,2, 3-Tri chl oropropane
1,1, 1-Trichl oro-2-propanone
Trifluralin
Fort.
Cone. ,
//g/L
0
0
0
0
0
0
.010
.140
.010
.156
.010
.022
Obser.a
Cone.,
0
0
0
0
0
0
.020
.133
.009
.160
.011
.024
Avg.
%Rec.
200
95
90
103
110
109
%RSD
19
3
13
3
7
3
.22
.40
.77
.11
.11
.07
MDLb
0
.012
0.014
0
0
0
0
.004
.015
.002
.002
EDLe
^9/L
0.
0.
0.
0.
0.
0.
012
020
007
114
010
006
Surrogate -«>
Decafluorobyphenyl
10.0
10.6
106
1.78
(a) Based upon the analysis of eight replicate MTBE sample extracts.
(b) MDL designates the statistically derived MDL and is calculated by
multiplying the standard deviation of the eight replicates by the
student's t-yalue (2.998) appropriate for a 99% confidence level and a
standard deviation estimate with n-1 degrees of freedom.
(c) Estimated Detection Limit (EDL) ~ Defined as either the MDL or a
level of compound in a sample yielding'a peak in the final extract
with a signal to noise (S/N) ratio of approximately 5, whichever is
greater.
(d) NR indicates Not Reported since their was no peak detected for the
eight replicate MDL determination.
(e) The concentration of atrazine and simazine were added together for
this determination since these two peaks coelute on the confirmation
column.
551.1-41
-------
TABLE 3.A. PRECISION AND ACCURACY RESULTS USING MTBE"
NHAC1 PRESERVED FORTIFIED REAGENT WATER ON THE PRIMARY DB-l COLUMN
ANALYTE
Alachlor
Atrazine
Bromacil
Bromochl oroacetoni tri 1 e
Bromodi chl oromethane
Bromoform
Carbon Tetrachloride
Chloropicrin
Chloroform
Cyanazine
Di bromoaceton 1 tri 1 e
Dibromochl oromethane
1 , 2-Di bromo-3-chl oropropane
1 , 2-Di bromoethane
Di chl oroacetoni tri 1 e
1, l-Dichloro-2-propanone
Endrin
Endr in Aldehyde
Endrin Ketone
Heptachlor
Heptachlor Epoxide
Hexachl orobenzene
Hexachlorocyclopentadiene
Lindane (g-BHC)
Methoxychlor
Metolachlor
Metribuzin
Simazine
Tetrachl oroethyl ene
Tri chl oroacetoni tri 1 e
Fortified
Cone., //g/L
2.18
12.6
1.88
5.00
5.00
5.00
5.00
5.00
5.00
3.77
5.00
5.00
5.00
5.00
5.00
5.00
0.311
0.437
0.310
0.313
0.875
0.124
0.374
0.188
1.26
4.39
1.24
12.5
5.00
5.00
Mean Meas.
Cone., //g/L
2.40
12.4
1.85
5.69
4.94
5.07
5.07
5.32
5.10
3.89
5.78
4.87
5.11
4.96
5.35
5.08
0.337
0.503
0.319
0.351
0.968
0.137
0.368
0.199
1.48
4.89
1.21
13.1
5.07
5.73
%RSD
1.47
1.71
3.13
0.71
1.14
0,72
1.72
1.38
1.30
2.85
1.43
0.71
0.59
0.73
0.57
0.72
1.40
1.32
1.52
2.84
0.65
0.89
1.18
1.41
2.84
0.87
3.94
2.02
1.62
1.34
Percent
Recovery
110
98
98
114
99
101
101
106
102
103
116
97
102
99
107
102
108
115
103
112
111
110
98
106
117
111
97
105
101
115
551.1-42
-------
TABLE 3.A. PRECISION AND ACCURACY RESULTS USING HTBE" (cont'd)
NH.C1 PRESERVED FORTIFIED REAGENT WATER ON THE PRIMARY DB-1 COLUMN
ANALYTE
1,1,1-Trichloroethane
1,1, 2-Tri chl oroethane
Trichloroethylene
1,2,3-Trichloropropane
1,1, l-Trichloro-2-propanone
Trifluralin
Fortified
Cone., fjq/L
5.00
2.80
5.00
3.12
5.00
0.439
Mean Meas.
Cone., //g/L
5.02
2.92
4.87
3.08
5.30
0.503
%RSD
1.22
0.91
1.48
0.62
0.81
1.09 -
Percent
Recovery
100
104
97
99
106
115
Surrogate -==>
Decaf1uorobyphenyl
10.0
10.4
1.93
104
(a) Based upon the analysis of eight replicate MTBE sample extracts.
551.1-43
-------
TABLE 3.B. PRECISION AND ACCURACY RESULTS USING MTBE *
Na,SO, PRESERVED FORTIFIED REAGENT WATER ON THE PRIMARY DB-1 COLUMN
ANALYTE
Bromod 1 chl oromethane
Bromoform
Carbon Tetrachlorlde
Chloral Hydrate
Chloroform
Dlbromochl oromethane
1 , 2-Di bromo-3-chl oropropane
1,2-Dlbroinoethane
Tetrachloroethylene
1,1,1 -Tr 1 chl oroethane
Trichloroethylene
Fortified
Cone., uq/l
5.00
5.00
5.00
1.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
Mean Meas.
Cone., ;/g/L
4.91
5.05
5.08
0.93
4.96
4.83
5.07
4.90
5.06
5.01
4.81
%RSD
1.49
1.32
2.24
1.81
1.71
1.43
1.04
1.02
2.53
2.11
2.21
Percent
Recovery
98
101
102
93
99
97
101
98
101
100
96
Surrogate ===>
Decaf1uorobyphenyl
10.0 10.2 1.88 102
(a) Based upon the analysis of eight replicate MTBE sample extracts.
551.1-44
-------
TABLE 3.C. PRECISION AND ACCURACY RESULTS USING MTBE*
NH4C1 PRESERVED FORTIFIED REAGENT WATER ON THE CONFIRMATION
Rtx-1301 COLUMN
ANALYTE
Alachlor
Bromacil
Bromochl oroaceton i tr i 1 e
Bromodlchloromethane
Bromoform
Carbon Tetrachloride
Chloropicrin
Chloroform
Cyanazine
D1 bromoacetoni tr i 1 e
01 bromochl oromethane
1 , Z-D1 bromo-3-chl oropropane
1,2-Dibromoethane
Di chl oroaceton i tr i 1 e
1 , 1-D1 chl oro-2-propanone
Endrin
Endrln Aldehyde
Endrin Ketone
Heptachlor
Heptachlor Epoxide
Hexachl orobenzene
Hexachlorocyclopentadiene
Lindane (g-BHC)
Methoxychlor
Metolachlor
Met ri buz in
Simazine/Atrazine
Tetrachl oroethy 1 ene
Tri chl oroaceton i tri 1 e
Fortified
Cone., //g/L
2.18
1.88
5.00
5.00
5.00
5.00
5.00
5,00
3.77
5.00
5.00
5.00
5.00
5.00
5.00
0.310
0.440
0.310
0.310
0.880
0.124
0.374
0.188
1.26
4.39
1.24
25.1 b
5.00
5.00
Mean Meas.
Cone., jjq/L
2.26
1.77
5.59
4.92
5.04
4.90
5.24
5.05
3.90
5.47
5.04
5.12
5.09
5.30
4.94
0.335
0.490
0.317
0.349
0.978
0.135
0.474
0.205
1.42
4.57
1.29
30.0
4.93
5.48
%RSO
0.81
3.50
0.86
1.02
0.73
1.72
1.20
1.20
2.30
0.58
0.90
0.54
1.82
0.55
0.70
2.08
2.13
1.63
1.06
0.80
0.59
7.19
0.75
2.30
3.43
1.15
1.11
1.65
1.31
Percent
Recovery
104
94
112
98
101
98
105
101
103
109
101
102
102
106
99
108
111
102
113
111
109
127
109
113
104
104
119
99
110
551.1-45
-------
TABLE 3.C. PRECISION AND ACCURACY RESULTS USING NTBE * (cont'd)
NH,C1 PRESERVED FORTIFIED REAGENT WATER ON THE CONFIRMATION
Rtx-1301 COLUMN
ANALYTE
1 , 1 , 1-Tri chl oroethane
1 , 1 ,2-Trichl oroethane
Trichloroethylene
1,2, 3-Tri chl oropropane
1,1, 1-Tri chl oro-2-propanone
Trifluralin
Fortified
Cone., fjg/l
5.00
2.80
5.00
3.12
5.00
0.440
Mean Meas.
Cone., jjq/L
4.87
2.76
4.87
3.07
4.90
0.486
%RSD
1.66
1.52
1.52
0.88
0.89
0.93
Percent
Recovery
97
98
97
98
98
110
Surrogate ===> 10.0 10.6 1.96 106
Decafluorobyphenyl
(a) Based upon the analysis of eight replicate MTBE sample extracts.
(b) Simazine and atrazine coelute on the confirmation coTumn and therefore
there results were added together.
551.1-46
-------
TABLE 3.D. PRECISION AND ACCURACY RESULTS USING NTBE *
Na,SO, PRESERVED FORTIFIED REAGENT WATER ON THE CONFIRMATION
Rtx-1301 COLUMN
ANALYTE
Bromodichloromethane
Bromoform
Carbon Tetrachloride
Chloroform
Dibromochloromethane
1 , 2-Di bromo-3-chl oropropane
1,2-Dibromoethane
Tetrachl oroethyl ene
1,1,1-Trlchloroethane
Trlchl oroethyl ene
Fortified
Cone., fjq/l
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
Mean Meas.
Cone., //g/L
4.88
5.03
4.90
4.90
5.15
5.07
5.02
4.89
4.84
4.83
%RSD
1.53
1.19
2.27
1.58
1.78
0.94
0.82
2.47
2.18
2.06
Percent
Recovery
98
101
98
98
103
101
100
98
97
97
Surrogate ===> 10.0 10.3 1.64
Decaf1uorobyphenyl
(a) Based upon the analysis of eight replicate MTBE sample extracts.
103
551.1-47
-------
TABLE 4.A. PRECISION AND ACCURACY RESULTS USING MTBE*
NH^CI PRESERVED FORTIFIED REAGENT WATER ON THE PRIMARY DB-1 COLUMN
ANALYTE
Alachlor
Atrazine
Bromacll
Bromochl oroacetoni tri 1 e
Bromodichloromethane
Bromoform
Carbon Tetrachloride
Chloropicrin
Chloroform
Cyanazine
Di bromoacetoni tri 1 e
Di bromochl oromethane
1 , 2-Dibromo-3-chl oropropane
1,2-Dibromoethane
Dichl oroacetoni tri 1 e
1 , 1-Di chl oro-2-propanone
Endrin
Endrin Aldehyde
Endrin Ketone
Heptachlor
Heptachlor Epoxide
Hexachl orobenzene
Hexachl orocycl opentadi ene
Lindane (g-BHC)
Methoxychlor
Metolachlor
Metribuzin
Simazine
Tetrachloroethylene
Trlchloroacetonitrile
Fortified
Cone., uq/l
0.436
2.520
0.376
0.250
0.250
0.250
0.250
0.250
0.250
0.754
0.250
0.250
0.250
0.250
0.250
0.250
0.062
0.087
0.062
0.063
0.175
0.025
0.075
0.038
0.252
0.878
0.248
2.500
0.250
0.250
Mean Meas.
Cone. , //g/L
0.515
2.994
0.376
0.281
0.276
0.260
0.299
0.285
0.264
0.761
0.276
0.266
0.261
0.274
0.268
0.261
0.073
0.108
0.062
0.059
0.206
0.030
0.074
0.047
0.298
1.056
0.264
2.960
0.263
0.29.1
%RSD
1.84
1.95
3.32
1.57
1.42
1.62
1.60
2.03
1.94
1.97
1.89
1.20
1.82
1.89
1.12
0.91
2.65
1.29
0.76
10.29
0.90
3.77
3.22
2.74
3.24
1.00
2.15
2.71
1.93
1.02
Percent
Recovery
118
119
100
113
110
104
120
114
105
101
110
106
104
110
107
105
117
123
100
93
118
120
99
125
118
120
107
118
105
116
551.1-48
-------
TABLE 4.A. PRECISION AND ACCURACY RESULTS USING MTBE1 (cont'd)
NH.C1 PRESERVED FORTIFIED REAGENT WATER ON THE PRIMARY DB-1 COLUMN
* *
ANALYTE
1,1, 1-TMchloroethane
1,1, 2-THchl oroethane
Trlchloroethylene
1,2, 3-Tr1 chl oropropane
1,1, l-Tr1 chl oro-2-propanone
Trlfluralln
Fortified
Cone., jug/L
0.250
0.560
0.250
0.624
0.250
0.088
Mean Meas.
Cone., fjg/l
0.291
0.531
0.252
0.595
0.286
0.106
%RSD
3.65
0.85
1.20
0.83
3.72
1.50
Percent
Recovery
116
95
101
95
114
121
Surrogate ««>
Decafluorobyphenyl
10.0 10.9 2.49 109
(a) Based upon the analysis of eight replicate MTBE sample extracts.
551.1-49
-------
TABLE 4.B. PRECISION AND ACCURACY RESULTS USING NTBE*
Na,SO, PRESERVED FORTIFIED REAGENT WATER ON THE PRIMARY DB-1 COLUMN
ANALYTE
Bromodichloromethane
Bromoform
Carbon Tetrachloride
Chloral Hydrate
Chloroform
Di bromochl oromethane
1 , 2-Di bromo-3-chl oropropane
1,2-Dibromoethane
Tetrachl oroethyl ene
1,1, 1-Trichl oroethane
Trichl oroethyl ene
Fortified
Cone., fjg/l
0.250
0.250
0.250
0.250
0.250
0.250
0.250
0.250
0.250
0.250
0.250
Mean Meas.
Cone., fjg/l
0,270
0.257
0.287
0.258
0.248
0.261
0.258
0.243
0.256
0.276
0.246
%RSD
1.77
2.04
5.18
4.12
1.88
1.36
1.26
0.90
1.95
5.72
1.01
Percent
Recovery
108
103
115
103
99
105
103
97
102
110
98
10.0 10.6 3.51 106
(a) Based upon the analysis of eight replicate MTBE sample extracts.
Surrogate «=>
Decaf1uorobyphenyl
551.1-50
-------
TABLE 5.A. PRECISION AND ACCURACY RESULTS USING MTBEa
NH4C1 PRESERVED FORTIFIED FULVIC ACID ENRICHED REAGENT WATER6 ON THE PRIMARY
DB-1 COLUMN
ANALYTE
Alachlor
Atrazlne
Bromacil
Bromochl oroacetoni tri 1 e
Bromodichloromethane
Bromoform
Carbon Tetrachloride
Chloropicrin
Chloroform
Cyanazine
D1 bromoaceton 1 tri 1 e
Di bromochl oromethane
1 , 2-Dibromo-3-chl oropropane
1,2-Dibromoethane
Dichl oroacetoni irile
l,l-Dichloro-2-propanone
Endrln
Endrin Aldehyde
Endrln Ketone
Heptachlor
Heptachlor Epoxide
Hexachl orobenzene
Hexachl orocycl opentadi ene
Lindane (g-BHC)
Methoxychlor
Metolachlor
Metribuzin
Simazine
Tetrachl oroethyl ene
Fortified
Cone., jjq/l
2.18
12.6
1.88
1.00
1.00
1.00
1.00
1.00
1.00
3.77
1.00
1.00
.1.00
1.00
1.00
1.00
0.311
0.437
0.310
0.313
0.875
0.124
0.374
0.188
1.26
4.39
1.24
12.5
1.00
Mean Meas.
Cone. , fjq/i
2.38
11.6
1.89
1.11
0.87
0.97
0.88
1.13
1.03
4.02
1.14
0.89
0.93
0.96
1.05
1.03
0.325
0.505
0.319
0.358
0.978
0.139
0.363
0.206
1.41
4.84
1.30
12.0
0.90
%RSD
1.57
2.31
3.33
1,51
1.93
1.50
3.91
2.49
2.47
3.99
1.61
1.78
1.37
1.58
0.98
0.90
3.50
1.99
2.62
5.45
1.28
1.82
3.55
1.79
4.78
1.27
2.08
1.09
4.02
Percent
Recovery
109
92
101
111
87
97
88
113
103
107
114
89
93
96
105
103
104
116
103
114
112
112
97
110
112
110
105
96
90
551.1-51
-------
TABLE 5.A. PRECISION AND ACCURACY RESULTS USING NTBE * (cont'd)
NH4C1 PRESERVED FORTIFIED FULVIC ACID ENRICHED REAGENT WATERb ON THE PRIMARY
* DB-1 COLUMN
ANALYTE
Trichloroacetonitrile
1,1,1-Trichloroethane
1,1, 2-Trichl oroethane
Trichloroethylene
1,2, 3-Tr i chl oropropane
l,l,l-Trichloro-2-propanone
Trifluralin
Fortified
Cone., uq/L
1.00
1.00
2.80
1.00
3.12
1.00
0.439
Mean Meas.
Cone., fjq/l
1.11
0.96
2.81
0.93
2.92
1.10
0.517
%RSD
2.41
3.89
2.89
3.55
0.82
2.05
1.27
Percent
Recovery
111
96
100
93
93
110
118
Surrogate ===> 10.0 10.4 1.84 104
Decafluorobyphenyl
(a) Based upon the analysis of eight replicate MTBE sample extracts.
(b) Reagent water fortified at 1.0 mg/L with fulvic acid extracted from
Ohio River water. Sample simulated high TOC matrix.
551.1-52
-------
TABLE 5.B. PRECISION AND ACCURACY RESULTS USING KTBE *
Na,S03 PRESERVED FORTIFIED FULVIC ACID ENRICHED REAGENT WATER ON THE PRIMARY
DB-1 COLUMN
ANALYTE
Bromodi chl oromethane
Bromoform
Carbon Tetrachloride
Chloral Hydrate
Chloroform
D1 bromochl oromethane
1 , 2-Di bromo-3-chl oropropane
1,2-Dibromoethane
Tetrachl oroethyl ene
1,1, 1-Trlchl oroethane
Trichl oroethyl ene
Fortified
Cone., fjg/l
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
Mean Meas.
Cone., //g/L
0.87
0.97
0.88
0.90
0.96
0.88
0.92
0.93
0.90
0.97
0.94
%RSD
1.13
1.28
1.71
0.95
1.51
1.25
0.98
1.01
2.07
1.57
1.62
Percent
Recovery
87
97
88
90
96
88
92
93
' 90
97
94
Surrogate ===> 10.0 10.6 2.56 106
Decafluorobyphenyl
(a) Based upon the analysis of eight replicate MTBE sample extracts.
(b) Reagent water fortified at 1.0 mg/L with fulvic acid extracted from
Ohio River water. Sample simulated high TOC matrix.
551.1-53
-------
TABLE 6.A. PRECISION AND ACCURACY RESULTS USING NTBE"
NH4C1 PRESERVED FORTIFIED GROUND WATER* ON THE PRIMARY
OB-1 COLUMN
ANALYTE
Alachlor
Atrazlne
Bromacll
Bromochl oroacetoni tri 1 e
Bromodichl oromethane
Bromoform
Carbon Tetrachloride
Chloropicrin
Chloroform
Cyanazlne
Di bromoacetoni tri 1 e
D1 bromochl oromethane
1 , 2-D1 bromo-3-chl oropropane
1,2-Dibromoethane
Dichloroacetonltrile
l,l-Dichloro-2-propanone
Endrin
Endrin Aldehyde
Endrin Ketone
Heptachlor
Heptachlor Epoxide
Hexachl orobenzene
Hexachlorocyclopentadiene
Lindane (g-BHC)
Hethoxychlor
Metolachlor
Hetribuzin
Simazine
Tetrachloroethylene
Unfort.
matrix
cone.,
V9/L
NO c
ND
NO
ND
1.70
20.1
ND
ND
0.571
ND
ND
6.00
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
Fort.
Cone.,
//9/L
8.72
50.4
7.52
5.00
5.00
5.00
5.00
5.00
5.00
15.1
5.00
5.00
5.00
5.00
5.00
5.00
1.24
1.75
1.24
1.25
3.50
0.50
1.50
0.75
5.04
17.6
4.96 .
50.0
5.00
Mean
Meas.
Cone.,
/*/L
9.01
46.7
6.53
5.74
6.68
24.8
4.99
5.29
5.73
15.4
5.84
11.1
5.04
4.87
5.29
5.01
1.32
1.91
1.22
1.33
3.67
0.509
1.41
0.773
5.60
18.2
4.85
48.3
4.97
%RSD
2.93
3.30
7.81
1.38
2.59
1.61
6.65
3.59
3.68
6.07
1.59
1.89
1.64
1,90
1.52
1.30
4.81
2.36
3.77
4.46
2.92
3.42
3.70
1.91
5.86
3.06
6.15
3.30
6.29
Percent
Recovery
103
93
87
115
100
95
100
106
103
102
117
102
101
97
106
100
106
109
98
106
105
103
94
103
111
103
98
97
99
551.1-54
-------
TABLE 6.A. PRECISION AND ACCURACY RESULTS USING HTBE* (cont'd)
NH,C1 PRESERVED FORTIFIED GROUND WATERb ON THE PRIMARY
DB-1 COLUMN
ANALYTE
Trichloroacetonitrlle
1,1, 1-Trichl oroethane
1,1, 2-Tri chl oroethane
Trichloroethylene
1,2,3-Trichloropropane
1,1, 1-Tr i chl oro-2-propanone
Trlfluralin
Unfort.
matrix
cone.,
*/g/L
ND
1.77
ND
ND
0.340
ND
ND
Fort.
Cone.,
W/l
5.00
5.00
11.2
5.00
12.5
5.00
1.76
Mean
Meas.
Cone.,
W/L
5.59
6.62
10.4
4.74
12.5
5.21
1.94
%RSD
4.89
4.60
2.98
5.78
3.92
1.58
3.38
Percent
Recovery
112
97
93
95
97
104
110
Surrogate =«> 10.0 10.4 2.25 104
Decafluorobyphenyl
(a) Based upon the analysis of eight replicate MTBE sample extracts.
(b) Chlorinated ground water from a water source displaying a hardness of
460 mg/L as CaC03.
(c) ND Indicates not detected above the EDL.
551.1-55
-------
TABLE 6.B. PRECISION AND ACCURACY RESULTS USING MTBE*
Na,SO, PRESERVED FORTIFIED GROUND WATERb ON THE PRIMARY DB-1 COLUMN
ANALYTE
Bromodichloromethane
Bromoform
Carbon Tetrachloride
Chloral Hydrate
Chloroform
Di bromochl oromethane
1 , 2-Dibromo-3-chl oropropane
1,2-Dibromoethane
Tetrachl oroethy 1 ene
1,1, 1-Trichloroethane
Trlchloroethylene
Unfort.
matrix
cone.,
jug/L
1.77
20.5
NO c
NO
0.600
6.16
NO
ND
ND
1.91
ND
Fort.
Cone.,
M/L
5.00
5.00
5.00
2.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
Mean
Meas.
Cone.,
jug/L
6.64
24.6
4.99
1.84
5.22
11.0
5.01
4.79
4.95
6.73
4.69
%RSD
1.70
1.63
2.72
1.38
1.89
1.53
1.19
1.86
2.49
3.18
2.38
Percent
Recovery
97
82
100
92
92
98
100
96
99
96
94
Surrogate ===>
Decafluorobyphenyl
10.0
10.1
8.71 101
(a) Based upon the analysis of eight replicate MTBE sample extracts.
(b) Chlorinated ground water from a water source displaying a hardness of
460 mg/L as CaC03.
(c) ND Indicates Not Detected above the detection limit.
551.1-56
-------
TABLE 7. LABORATORY PERFORMANCE CHECK SOLUTION
Parameter
Instrument
Sensitivity
Chromatographic
Performance
Col umn
Performance
Analyte
Breakdown
Analyte
lindane
(gamma-BHC)
Hexachlorocyclopentadiene
Bromodichloromethane
Trichloroethylene
Bromacil
Alachlor
Endrin
Cone.,
//g/mL
in MTBE
or pentane
0.000200
0.0200
0.0300
0.0300
0.0830
0.0830
0.0300
Acceptance
Criteria
Detection of
Analyte;
Signal to
Noise > 3
PGF between
0.80 and 1.15"
Resolution >
0.50b
Resolution >
0.50
%BDC < 20 %
PGF = Peak Gaussian Factor. Calculated using the equation:
1.83 x W(l/2)
PGF = ................ ----
where W(l/2) is the peak width at half height and W(l/10) 1s the
peak width at tenth height.
Resolution between the two peaks as defined by the equation:
t
R - -----
W
where t 1s the difference in elution times between the two peaks and
W is the average peak width, at the baseline, of the two peaks.
%BD - Percent Breakdown. Endrin breakdown calculated using the
equation.
(AREA Endrin Ketone + AREA Endrin Aldehyde)
X 100
(AREA Endrin Ketone + AREA Endrin Aldehyde + AREA Endrin)
Note: If laboratory EDL's differ from those listed in this method,
concentrations of the LPC standard must be adjusted to be
compatible with the laboratory EDL's.
551.1-57
-------
TABLE 8. METHOD DETECTION LIMIT USING PENTANE
NH4C1 PRESERVED REAGENT WATER ON PRIMARY DB-1 COLUMN
ANALYTE
Alachlor
Atrazine
Bromacil
Bromochl oroaceton i tr i 1 e
Bromodi chl oromethane
Bromoform
Carbon Tetrachloride
Chloropicrin
Chloroform
Cyanazine
Di bromoacetoni tr i 1 e
01 bromochl oromethane
1 , 2-Di bromo-3-chl oropropane
1,2-Dibromomethane
Dichloroacetonitrile
i;i-Dichloro-2-propanone
Endrln
Endrln Aldehyde
Endrln Ketone
Heptachlor
Heptachlor Epoxide
Hexachl orobenzene
Hexachloropentadlene
Lindane (g-BHC)
Methoxychlor
Metolachlor
Metribuzin
Simazine
Tetrachl oroethyl ene
Fort.
Cone.
//9/L
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.109
.633
.094
.040
.040
.040
.040
.040
.040
.189
.040
.040
.040
.040
.040
.040
.016
.022
.016
.016
.044
.0062
.040
.0094
.063
.219
.062
.625
.040
Observ.b
Cone.
//9/L
0.
0
0
0
0
0
0
0
0
0.
0
0
0
0
0
0
0
0
0
0.
0
0
0
0
0
0
0
0
0
095a
.663
.058
.047
.054
.033
.060
.045
.110
170a
.046
.050
.053
.053
.037
.042
.019
.023
.014
Olla
.045
.008
.022
.006
.069
.267
.076
.662
.052
Avg.
%Rec.
87
105
62
118
135
83
150
113
275
90
115
125
133
133
93
105
119
105
88
69
102
129
55
64
110
122
123
106
130
%RSD
5.
5.
21.
3.
42.
20.
27.
4.
24.
13.
3.
5.
5.
19.
20.
4.
4.
5.
9.
18.
5.
9.
24.
91.
12.
10.
18.
9.
5.
37
00
44
61
05
60
76
25
36
37
84
48
39
85
09
86
69
52
50
14
02
56
42
20
76
35
15
42
33
MDLe
//9/L
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.015
.099.
.037
.005
.068
.020
.050
.006
.080
.068
.005
.008
.009
.032
.022
.006
.003
.004
.004
.006
.007
.002
.016
.017
.026
.083
.041
.187
.008
EDLd
V9/L
0
0
.050
.390
0.330
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
.026
.068
.035
.050
.023
.080
.200
.030
.026
.017
.032
.042
.022
.016
.022
.020
.009
.016
.002
.016
.017
.066
.172
.041
.420
.016
551.1-58
-------
TABLE 8. METHOD DETECTION LIMIT USING PENTANE (cont'd)
NH4C1 PRESERVED REAGENT WATER ON PRIMARY DB-1 COLUMN
ANALYTE
Tri chl oroacetoni tri 1 e
1,1, 1-Tri chl oroethane
1 , 1 ,2-Trichl oroethane
Tr 1 chl oroethyl ene
1,2,3-Trichloropropane
1,1, 1-TMchl oro-2-propanone
Trifluralin
Fort.
Cone.
//g/L
0.040
0.040
0.140
0.040
0.156
0.040
0.040
Observ.b
Cone.
W/L
0.048
0.058
0.141
0.064
0.151
0.045
0.021
Avg.
%Rec.
120
145
101
160
97
113
53
%RSD
2.79
4.26
4.01
21.80
3,54
3.65
19.28
MDLC
//9/L
0.004
0.007
0.017
0.042
0.016
0.005
0.012
EDLd
//g/L
0.014
0.017
0.052
0.042
0.116
0.024
0.012
Surrogate =«>
Decafluorobyphenyl
10.0
11.2 112
3.98
(a) Quantitated from confirmation column due to baseline interference on
primary column.
(b) Based upon the analysis of eight replicate pentane sample extracts.
(c) MDL designates the statistically derived MDL and is calculated by
multiplying the standard deviation of the eight replicates by the
student's t-value (2.998) appropriate for a 99% confidence level and a
standard deviation estimate with n-1 degrees of freedom.
(d) Estimated Detection Limit (EDL) — Defined as either the MDL or a level
of compound in a sample yielding a peak in the final extract with a
signal to noise (S/N) ratio of approximately 5, wbv never is greater.
551.1-59
-------
TABLE 9. PRECISION AND ACCURACY RESULTS*
USING PENTANE
NH4C1 PRESERVED FORTIFIED REAGENT WATER ON THE PRIMARY DB-1 COLUMN
ANALYTE
Alachlor
Atrazine
Bromacil
Bromochl oroacetonl tr i 1 e
Bromodichloromethane
Bromoform
Carbon Tetrachloride
Chloropicrin
Chi orof orm
Cyanazine
D1 bromoacetoni tr 11 e
Dlbromochloromethane
1 , 2-Di bromo-3-chl oropropane
1,2-Dibromoethane
Dichloroacetonitrile
1 , 1-D1 chl oro-2-propanone
Endrin
Endrin Aldehyde
Endrin Ketone
Heptachlor Epoxlde
Heptachlor
Hexachlorobenzene
Hexachlorocyclopentadiene
Llndane (g-BHC)
Methoxychl or
Metolachlor
Metribuzin
Simazlne
Tetrachl oroethyl ene
Fortified
Cone., /yg/L
2.18
12.6
1.88
5.00
5.00
5.00
5.00
5.00
5.00
3.77
5.00
5.00
5.00
5.00
5.00
5.00
0.311
0.437
0.310
0.875
0.313b
0.124
0.374
0.188
1.26
4.39
1.24
12.5
5.00
Mean Meas.
Cone., jjg/L
1.98 b
12.0
1.74
4.63
4.46
4.81
4.61
4.51
4.95
4.00 b
4.80
4.23
4.73
4.69
4.73
4.78
0.312
0.443
0.311
0.866
0.30
0.123
0.384
0.176
1.28
4.42
1.34
12.5
4.46
%RSD
5.09
3.09
2.95
3.18
4.07
2.76
4.14
2.46
2.90
2.59
2.87
3.38
3.00
2.54
3.39
3.04
2.61
2.29
2.10
2.11
3.47
2.51
3.30
10.23
3.03
2.36
2.13
2.20
3.67
Percent
Recovery
91
95
93
93
89
96
92
90
99
106
96
85
95
94
95
96
100
101
100
99
97
99
103
94
102
101
108
100
89
551.1-60
-------
TABLE 9. PRECISION AND ACCURACY RESULTS' (cont'd)
USING PENTANE
NH4C1 PRESERVED FORTIFIED REAGENT WATER ON THE PRIMARY DB-1 COLUMN
ANALYTE
Tri chl oroacetoni tri 1 e
1,1,1-Trichloroethane
1,1, 2-Tri chl oroethane
Trichloroethylene
1,2,3-Trichloropropane
1, 1, l-Trichloro-2-propanone
Trifluralin
Surrogate===>
Decaf 1 uorobyphenyl
Fortified
Cone., ^g/L
5.00
5.00
2.80
5.00
3.12
5.00
0.439
10.0
Mean Meas.
Cone., fjq/i
5.07
4.70
2.62
4.84
3.13
4.88
0.446
10.7
%RSD
4.02
3.39
2.03
2.98
1.76
2.80
2.74
1.88
Percent
Recovery
101
94
93
97
100
98
102
107
(a)
Based upon the analysis of eight replicate pentane sample extracts.
(b) Quantitated from confirmation column due to baseline interference
on primary column.
551.1-61
-------
TABLE 10. ANALYTE PEAK IDENTIFICATION, RETENTION TIMES,
CONCENTRATIONS AND CONDITIONS USING NTBE FOR FIGURE 1
NH,C1 PRESERVED FORTIFIED REAGENT WATER ON THE
PRIMARY DB-1 COLUMN
Retention
PEAK Time3
1 ANALYTE minutes
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Chloroform
1,1, 1-Tri chl oroethane
Carbon Tetrachloride
Tri chl oroacetoni tri le
Dichl oroacetoni tri 1 e
Bromodichloromethane
Trichloroethylene
Chloral Hydrate
1 , 1-Dichl oro-2-Propanone
1,1, 2-Tri chl oroethane
Chloropicrin
Di bromochl oromethane
Bromochl oroacetoni tri 1 e
1,2-Dibromoethane (EDB)
Tetrachl oroethyl ene
1,1, 1-Tri chl oropropanone
Bromoform
Dibromoacetonitrile
1,2, 3-Tri chl oropropane
1 , 2-Di bromo-3-chl oropropane (DBCP)
Surrogate: Decaf luorobiphenyl
Hexachl orocycl opentad i ene
Trlfluralin
Simazine
Atrazine
Hexachl orobenzene
Lindane (gamma-BHC)
Metribuzin
7.04
8.64
9.94
10.39
12.01
12.42
12.61
13.41
14.96
19.91
23.10
23.69
24.03
24.56
26.24
27.55
29.17
29.42
30.40
35.28
36.35
40.33
45.17
46.27
46.55
47.39
47.95
50.25
Cone.
m/i
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
44.8
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
50.0
5.00
10.0
28.0
7.04
200
200
1.98
30.1
19.9
551.1-62
-------
TABLE 10. ANALYTE PEAK IDENTIFICATION, RETENTION TIMES,
CONCENTRATIONS AND CONDITIONS USING MTBE FOR FIGURE 1 (cont'd)
NH,C1 PRESERVED FORTIFIED REAGENT WATER ON THE
PRIMARY DB-1 COLUMN
PEAK
#
29
30
31
32
33
34
35
36
37
38
NOTE:
ANALYTE
Bromacil
Alachlor
Cyanazine
Heptachlor
Metolachlor
Heptachlor Epoxide
Endrin
Endrin Aldehyde
Endrin Ketone
Methoxychlor
Bromofluorobenzene (ret.
standard was not Included
Retention
Time8
minutes
52.09
52.25
53.43
53.72
55.44
58.42
64.15
65.46
72.33
73.53
time 31.00 min.) as the
in this chromatogram.
Cone.
//g/L
30.1
34,9
60.4
5.00
70.0
14.0
5.00
7.00
4.96
20.1
ThternaT
(a) Column A -
0.25 mm ID x 30 m fused silica capillary with chemically
bonded methyl polysiloxane phase (J&W, DB-1, 1.0 fm film
thickness or equivalent). The linear velocity of the
helium carrier is established at 25 cm/sec at 35°C.
The column oven is temperature programmed as follows:
[1] HOLD at 35°C for 22 min
[2] INCREASE to 145°C at 10°C/min and hold at 145°C for 2 min.
[3] INCREASE to 225°C at 20°C/min and hold at 225°C for 15
min.
[4] INCREASE to 260°C at 10°C/min and hold at 260°C for 30
min. or until all expected compounds have eluted.
Injector temperature: 200°C
Detector temperature: 290°C
551.1-63
-------
FIGURE I. FORTIFIED REAGENT WATER EXTRACT USING HTBE ON PRIHARY DB-1 COLUMN
i
S
1
21
23
IS
u1 M
fill
45 SI
3
i
i
5
a
u
17
11 1,""
r
1 "
,
i , ll .IT
•- .,.»....!.. . ! . . . . 1 . . _ ^ 1 - - - J , .
11 IS a 25 31 35 «
MINUTES
34
* 33
»| 31
ll
31
ll. ll
SS 41 « 71 75 M 6
MINUTES
551'. 1-64
-------
TABLE 11. ANALYTE PEAK IDENTIFICATION, RETENTION TIMES,
CONCENTRATIONS AND CONDITIONS USING MTBE FOR FIGURE 2
NH,C1 PRESERVED FORTIFIED REAGENT WATER ON THE
CONFIRMATION RtX-1301
PEAK
f
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
Retention
Time*
ANALYTE minutes
Chloroform
1,1, 1-Tri chl oroethane
Carbon Tetrachloride
Trichloroacetoni tri 1 e
Trichloroethylene
Bromodichloromethane
1 , 1-Dichl oro-2-Propanone
Chloroplcrin
Tetrachl oroethyl ene
1,1, 2-Trichloroethane
Dichloroacetoni tri 1 e
Dibromochloromethane
1,2-Di bromoethane (EDB)
1,1, 1-THchl oropropancne
Bromochl oroacetoni tri 1 e
Bromoform
1 , 2 ,3-Tri chl oropropane
Oi bromoaceton i tr i 1 e
1,2-Di bromo-3-chl oropropane (DBCP)
Surrogate: Decaf luorobiphenyl
Hexachl orocycl opentadi ene
Trifluralin
Hexachl orobenzene
Atrazine/Simazine
Lindane (gamma-BHC)
Heptachlor
Metribuzin
7.73
7.99
8.36
10.35
11.96
15.28
20.50
23.69
24.77
25.01
25.21
26.32
26.46
28.47
29.86
30.36
31.73
32.77
36.11
36.28
39.53
45.43
46.47
48.56
49.68
53.15
53.92
Cone.
//9/L
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
44.8
5.00
5.00
5.00
5.00
5.00
5.00
50.0
5.00
5.00
10.0
28.0
7.04
1.98
400
30.1
5.00
19.9
551.1-65
-------
TABLE 11. ANALYTE PEAK IDENTIFICATION, RETENTION TINES,
CONCENTRATIONS AND CONDITIONS USING MTBE FOR FIGURE 2 (cont'd)
NH4C1 PRESERVED FORTIFIED REAGENT WATER ON THE
CONFIRMATION Rtx-1301
PEAK
f ANALYTE
Retention
Time8 Cone.
minutes fjg/L
28
29
30
31
32
33
34
35
36
NOTE:
Alachlor
Metolachlor
Heptachlor Epoxide
Bromacil
Cyanazine
Endrin
Endrin Aldehyde
Methoxychlor
Endrin Ketone
Bromof 1 uorobenzen
54.38
57.07
59.05
59.60
59.89
65.24
71.56
76.73
81.28
e (ret. time 31.30 min.) as th<
34.9
70.0
14.0
30.1
60.4
5.00
7.00
20.1
4.96
B" internal
(a) Column B -
standard was not included in this chromatogram.
0.25 mm ID x 30 m with chemically bonded 6 %
cyanopropylphenyl / 94 % dimethyl polysiloxane phase
(Restek, Rtx-1301, 1.0 pm film thickness or equivalent).
The linear velocity of the helium carrier gas is
established at 25 cm/sec at 35°C.
The column oven is temperature programmed as follows:
The column oven is temperature programmed as follows:
[1] HOLD at 35°C for 22 min
[2] INCREASE to 145°C at 10°C/min and hold at 145°C for 2 min
[3] INCREASE to 225°C at 20°C/min and hold at 225°C for 15 min
[4] INCREASE to 260°C at 10°C/min and hold at 260°C for 30
min. or until all expected compounds have eluted.
Injector temperature: 200°C
Detector temperature: 290PC
551.1-66
-------
FIGURE 2.
COLUMN
FORTIFIED REAGENT WATER EXTRACT USING MTBE OK CONFIRMATION Rtx-1301
12
If
U
IS
' II
17
21
I
II IS 21 25 31 35 It
MINUTES
22
• T
JL_b_L
M
45 51 55 it « 71 75 II 15
MINUTES
551.1-67 '
-------
TABLE 12. ANALYTE PEAK IDENTIFICATION, RETENTION TINES, CONCENTRATIONS
AND CONDITIONS USING PENTANE FOR FIGURE 3
NH4C1 PRESERVED FORTIFIED REAGENT WATER ON THE
PRINARY DB-1 COLUMN
Retention
PEAK Time"
•1 ANALYTE minutes
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
Chi orof orm
1,1, 1-Tr 1 chl oroethane
Carbon Tetrachloride
Trichloroacetonitrile
Di chl oroacetonl tri 1 e
Bromodi chl oromethane
Trichloroethylene
1 , 1-Dichl oro-2-Propanone
1,1, 2-Tri chl oroethane
Chloropicrin
01 bromochl oromethane
Bromochl oroacetonl tri 1 e
1,2-Dibromoethane (EDB)
Tetrachl oroethyl ene
1,1, 1-Tr 1 chl oropropanone
Bromoform
Dibromoacetonltrile
1,2, 3-Tr 1 chl oropropane
Internal Standard: Bromof 1 uorobenzene
l,2-Dibromo-3-chl oropropane (DBCP)
Surrogate: Decaf luorobiphenyl
Hexachl orocycl opent ad 1 ene
Trifluralin
Simazine
Atrazine
Hexachl orobenzene
Lindane (gamma-BHC)
8.41
10.26
11.56
12.03
13.53
13.73
13.89
15.60
18.57
20.49
21.03
21.25
22.03
24.75
27.94
30.97
31.45
32.82
33.60
38.34
39.48
43.92
49.04
50.08
50.37
51.11
51.66
Cone.
09/L
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
44.8
5.00
5.00
5.00
5.00
5.00
5.00
5.00
5.00
50.0
1.00 fjq/ml in
pentane extract
5.00
10.0
28.0
7.04
200
200
1.98
30.1
551.1-68
-------
TABLE 12. ANALYTE PEAK IDENTIFICATION, RETENTION TINES, CONCENTRATIONS
AND CONDITIONS USING PENTANE FOR FIGURE 3 (cont'd)
NH4C1 PRESERVED FORTIFIED REAGENT WATER ON THE
PRIMARY DB-1 COLUMN
PEAK
#
28
29
30
31
32
33
34
35
36
37
38
ANALYTE
Metribuzin
Bromacil
Alachlor
Cyanazine
Heptachlor
Metolachlor
Heptachlor Epoxide
Endrin
Endrin Aldehyde
Endrin Ketone
Methoxychlor
Retention
Time*
minutes
53.95
55.72
55.87
57.04
57.21
59.13
62.50
68.00
69.25
75.74
76.98
Cone.
W/L
19.9
30.1
34.9
60.4
5.00
70.0
14.0
5.00
7.00
4.96
20.1
(a) Column A -
0.25 mm ID x 30 m fused silica capillary with chemically
bonded methyl polysiloxane phase (J&W, DB-1, 1.0 /im film
thickness or equivalent). The linear velocity of the
helium carrier is established at 25 cm/sec at 35°C.
The column oven is temperature programmed as follows:
[1] HOLD at 15°C for 0 min
[2] INCREASE to 50°C at 2°C/min and hold at 50°C for 10 min
[3] INCREASE to 225°C at 10°C/min and hold at 225°C for 15 min
[4] INCREASE to 260°C at 10°C/min and hold at 260°C for 30
min. or until all expected compounds have eluted.
Injector temperature: 200°C
Detector temperature: 290°C
551.1-69
-------
FIGURE 3.
COLUMN
FORTIFIED REAGENT MATER EXTRACT USING PENTANE ON PRIMARY DB-1
1
J
ft
5 11
a n
23
1 JS 21
45 SI
J
t
* u *
n
21
s ; . M
u " w
1 1Z,/ I I
1 "M IS
» 1 1 1 "
{ n A 11 .Alii
15 a K * 15 41
MINUTES
u
11
3t"
111 ill n ,
i | • - - - ! • » • - f • - **ir-'l-ri'1 n I I I
55 M 15 71 75 H 15
MINUTES
551.1-70
-------
ADDENDUM TO METHOD 551.1
ERA Method 551 (a previous version of Method 551.1) used a 40 ml sample
collection vial and a 35 ml sample volume. The sample volume used in EPA
Method 551.1 was increased to 50 ml and the sample collection vial was
increased to a 60 ml size. This increase in sample volume permitted the use
of sufficient extracting solvent to fill two autosampler vials with the final
extract. Using a smaller sample size and less solvent may not provide a
sufficient volume of extract to do this with all types of autosamplers.
Although filling two vials is not required by the method, laboratories may
find this a prudent practice.
Many laboratories have large supplies of 40 ml sample containers already
in stock. Laboratories may use these bottles for sample collection, and may
extract a 35 ml sample if the sample volume to reagent ratios (such as solvent
to sample ratios, concentration of buffer, etc.) are maintained as specified
in EPA Method 551.1. However, laboratories are encouraged to analyze 50 mL
samples as specified in the 551.1 version of the method.
551.1-71
-------
-------
METHOD 552.1
DETERMINATION OF HALOACETIC ACIDS AND DALAPON IN
DRINKING WATER BY ION-EXCHANGE LIQUID-SOLID
EXTRACTION AND GAS CHRONATOGRAPHY WITH AN
ELECTRON CAPTURE DETECTOR
Revision 1.0
August 1992
Jlmnle M. Hodgeson
David Becker (Technology Applications Inc.)
ENVIRONMENTAL MONITORING SYSTEMS LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
552.1-1
-------
METHOD 552.1
DETERMINATION OF HALOACETIC ACIDS AND DALAPON
IN DRINKING HATER BY ION-EXCHANGE LIQUID-SOLID EXTRACTION
AND GAS CHROMAT06RAPHY WITH ELECTRON CAPTURE DETECTION
1. SCOPE AND APPLICATION
1.1
1.2
1.3
1.4
1.5
This 1s a gas chromatographic (GC) method (1) applicable to the
determination of the listed halogenated acetic acids In drinking
water, ground water, raw water and water at any Intermediate
treatment stage. In addition, the chlorinated herbicide, Dalapon,
is determined using this method.
Analvte
Monochloroacetic Acid
Dichloroacetic Acid
Trichloroacetic Acid
Monobromoacetic Acid
Bromochloroacetic Acid
Dibromoacetic Acid
Dalapon
Chemical Abstract Services
Registry Number
79-11-8
79-43-6
76-03-9
79-08-3
5589-96-3
631-64-1
75-99-0
This is a liquid-solid extraction method and 1s designed as a
simplified alternative to the liquid-liquid extraction approach of
Method 552 for the haloacetlc acids. This method also provides a
much superior technique for the determination of the herbicide,
dalapon, compared to the complex herbicide procedure described in
Method 515.1. The procedure also represents a major step in the
Incorporation of pollution prevention in methods development, in
that the use of large volumes of organic solvents Is eliminated.
This method 1s applicable to the determination of the target
analytes over the concentration ranges typically found In drinking
water (2, 3), subject to the method detection limits (MDL) listed in
Table 2. The MDLs observed may vary according to the particular
matrix analyzed and the specific Instrumentation employed. The
haloacetic acids are observed ubiquitously in chlorinated supplies
at concentrations ranging from < 1 to > 50 pg/L.
Reduced analyte recoveries may be observed in high ionic strength
matrices, particularly waters containing elevated sulfate concentra-
tions. Improved recoveries may be obtained by sample dilution at
the expense of higher MDLs. This effect Is discussed more exten-
sively in Sect. 4.2.
Tribromoacetic acid has not been Included because of problems
associated with stability and chromatography with this method.
552.1-2
-------
Mixed bromochloroacetic adds have recently been synthesized.
Bromochloroacetic add is present in chlorinated supplies and method
validation data are provided here. Commercial standards are now
available for this compound. The mixed trihalogenated acids may
also be present. These are not included because of current problems
with purity and the chromatography for these compounds.
1.6 This method is designed for analysts skilled in extract concentra-
tion techniques, derivatization procedures and the use of GC and
interpretation of gas chromatograms.
1.7 When this method is used for the analyses of waters from unfamiliar
sources, analyte identifications must be confirmed by at least one
additional qualitative technique, such as gas chromatography/mass
spectrometry (GO/MS) or by GC using dissimilar columns.
2. SUMMARY OF METHOD
2.1 A 100-mL volume of sample is adjusted to pH 5.0 and extracted with a
preconditioned miniature anion exchange column. NOTE: The use of
liquid-solid extraction disks is certainly permissible as long as
all the quality control criteria specified in Sect. 9 of this method
are met. The analytes are eluted with small allquots of acidic
methanol and esterified directly in this medium after the addition
of a small volume of methyl-tert-butyl ether (MTBE) as co-solvent.
The methyl esters are partitioned into the MTBE phase and identified
and measured by capillary column gas chromatography using an elec-
tron capture detector (GC/ECD).
3. DEFINITIONS
3.1 INTERNAL STANDARD (IS) — A pure analyte(s) added to a sample,
extract, or standard solution in known amount(s) and used to measure
the relative responses of other method analytes and surrogates that
are components of the same sample or solution. The internal stan-
dard must be an analyte that 1s not a sample component.
3.2 SURROGATE ANALYTE (SA) — A pure analyte(s), which Is extremely
unlikely to be found in any sample, and which is added to a sample
aliquot in known amount(s) before extraction or other processing and
Is measured with the same procedures used to measure other sample
components. The purpose of the SA is to monitor method performance
with each sample.
3.3 LABORATORY DUPLICATES (LD1 AND LD2) - Two aliquots of the same
sample taken in the laboratory and analyzed separately with identi-
cal procedures. Analyses of LD1 and LD2 indicate the precision
associated with laboratory procedures, but not with sample collec-
tion, preservation, or storage procedures.
3.4 FIELD DUPLICATES (FD1 AND FD2) — Two separate samples collected at
the same time and place under identical circumstances and treated
552.1-3
-------
exactly the same throughout field and laboratory procedures.
Analyses of FD1 and FD2 give a measure of the precision associated
with sample collection, preservation and storage, as well as with
laboratory procedures.
3.5 LABORATORY REAGENT BLANK (LRB) — An aliquot of reagent water or
other blank matrix that are 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 appara-
tus.
3.6 FIELD REAGENT BLANK (FRB) -- An aliquot of reagent water or other
blank matrix that is placed in a sample container in the laboratory
and treated as a sample in all respects, including shipment to the
sampling site, 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.
3.7 LABORATORY FORTIFIED BLANK (LFB) — An aliquot of reagent water or
other blank matrix to which known quantities of the method analytes
are added in the laboratory. The LFB is analyzed exactly like a
sample, and Us purpose is to determine whether the methodology is
In control, and whether the laboratory is capable of making accurate
and precise measurements.
3.8 LABORATORY FORTIFIED SAMPLE MATRIX (LFM) — An aliquot of an envi-
ronmental 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 concen-
trations 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.
3.9 STOCK STANDARD SOLUTION (SSS) — A concentrated solution containing
one or more method analytes prepared in the laboratory using assayed
reference materials or purchased from a reputable commercial source.
3.10 PRIMARY DILUTION STANDARD SOLUTION (PDS) « 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.
3.11 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.
552.1-4
-------
3.12 QUALITY CONTROL SAMPLE (QCS) — A solution of method analytes of
known concentration which is used to fortify an aliquot of LRB or
sample matrix. The QCS is obtained from a source external to the
laboratory and different from the source of calibration standards.
It 1s used to check laboratory performance with externally prepared
test materials.
4. 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 significant interferences under the conditions of the analysis
by analyzing laboratory reagent blanks as described in Sect. 9.2.
4.1.1 For each set of samples analyzed, the reagent blank concen-
tration values exceeding 0.1 fig/I should be subtracted from
the sample concentrations. A persistent reagent blank of
approximately 1 pg/L was observed for bromochloroacetic acid
(BCAA) on the primary DB-1701 column. The background was
clean on the DB-210 confirmation column and the MDL for BCAA
in Table 2 was determined using this column.
4.1.2 Glassware must be scrupulously cleaned (4). Clean all
glassware as soon as possible after use by thoroughly rins-
ing with the last solvent used in it. Follow by washing
with hot water and detergent and thorough rinsing with tap
water, dilute acid, and reagept water. Drain and heat in an
oven or muffle furnace at 400 C for 1 hr. Do not heat
volumetric ware. Thermally stable materials such as PCBs
may not be eliminated by this treatment. Thorough rinsing
with reagent grade acetone may be substituted for the heat-
ing. After drying and cooling, store glassware in a clean
environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
4.1.3 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. The
extraction solvent, MTBE, may need to be redistilled.
4.2 The major potential interferences in this ion-exchange procedure are
other naturally occurring ions in water sources, principally sul-
fate. This is the only ion thus far demonstrated as an interfer-
ence, when present at concentrations possibly occurring in drinking
water sources. Sulfate as an effective counter ion displaces the
haloacids from the column when present at concentrations above 200
mg/L. Table 4 illustrates this effect for fortified reagent water
containing 500 mg/L and 400 mg/L of Na2S04 and NaCl respectively
(approximately 3.7 millimole (mM) in both cases). Markedly reduced
recoveries are observed for all analytes in the presence of high
552.1-5
-------
concentrations of sulfate. Reduced recoveries may be observed for
the monohaloacetic acids in very high ionic strength waters, as
illustrated for the sample with 400 mg/L NaCl. However, normal
recoveries were observed from a water sample containing the same
molar concentration of CaCl2. The only preventive measure currently
available for high ionic strength waters is sample dilution.
Dilution by a factor of 5 will suffice in the vast majority of
cases, although a factor of 10 may be required in a few extreme
sites (e.g. western waters with sulfate > 1000 mg/L). The HOLs will
still be approximately 1 pg/l for a dilution factor of 5. However,
for many chlorinated supplies the monohaloacetic acids may occur at
concentrations near 1 /ig/L. In any event, this is the recommended
method to determine dalapon.
4.3 The acid forms of the analytes are strong organic acids which react
readily with alkaline substances, and can be lost during sample
preparation. Glassware must be acid rinsed with 1:9 hydrochloric
acid: water prior to use to avoid analyte losses due to adsorption.
4.4 Organic acids and phenols, especially chlorinated compounds, are the
most direct potential interferences with the determination. The
procedure includes a methanol wash step after the acid analytes are
adsorbed on the column. This step eliminates the potential for
interferences from neutral or basic, polar organic compounds present
in the sample.
4.5 Interfering contamination may occur when a sample containing low
concentrations of analytes is analyzed immediately following a
sample containing relatively high concentrations of analytes.
Routine between-sample rinsing of the sample syringe and associated
equipment with MTBE can minimize sample cross-contamination. After
analysis of a sample containing high concentrations of analytes, one
or more injections of HT6E should be made to ensure that accurate
, values are obtained for the next sample.
4.6 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 water
sampled. Tentative identifications should be confirmed using the
confirmation column specified in Table 1 or by the use of gas
chromatography with mass spectrometric detection.
5.1 The toxicity or carcinogenicity of each reagent used in this method
has not been precisely defined; however, each chemical compound must
be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be minimized. The laboratory is
responsible for maintaining a current awareness file of OSHA regula-
tions regarding the safe handling of the chemicals specified in this
method. A reference file of material data handling sheets should
also be made available to all personnel involved in the chemical
552.1-6
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analysis. Additional references to laboratory safety are available
and have been Identified (5-7) for the Information of the analyst.
5.2 The toxiclty of the extraction solvent, MTBE, has not been well
defined. Susceptible Individuals may experience adverse affects
upon skin contact or Inhalation of vapors. For such Individuals a
mask may be required. Protective clothing and gloves should be used
and MTBE should be used only in a chemical fume hood or glove box.
6. EQUIPMENT AND SUPPLIES
6.1 SAMPLE CONTAINERS — Amber glass bottles, approximately 250 ml,
fitted with Teflon-lined screw caps. At least 200 ml of sample
should be collected.
6.2 GAS CHROMATOGRAPH (GC) — Analytical system complete with GC
equipped for electron capture detection, spllt/splitless capillary
Injection, temperature programming, differential flow control, and
with all required accessories including syringes, analytical col-
umns, gases and strip-chart recorder. A data system is recommended
for measuring peak areas. The gases flowing through the electron
capture detector should be vented through the laboratory fume hood
system.
6.3 PRIMARY GC COLUMN — DB-1701 or equivalent bonded, fused silica
column, 30 m x 0.32 mm ID, 0.25 pi film thickness. Another type of
column may be used if equivalent or better separation of analytes
can be demonstrated.
6.4 CONFIRMATORY GC COLUMN - DB-210 or equivalent bonded, fused silica
column, 30 m x 0.32 mm ID, 0.50 pm film thickness. Another type of
column may be used if equivalent or better separation of analytes
can be demonstrated.
6.5 PASTEUR PIPETS, GLASS DISPOSABLE
6.6 pH METER — Wide range with the capability of accurate pH measure-
ments at pH 5 ± 0.5.
6.7 15-mL amber colored bottles with Teflon-lined screw caps.
6.8 LIQUID-SOLID EXTRACTION VACUUM MANIFOLD - Available from a number
of suppliers.
6.9 LSE CARTRIDGES (1 ml) AND FRITS - Also available from a number of
suppliers. The use of LSE disks instead of cartridges is permissi-
ble as long as all the quality control criteria in Sect. 9 of this
method are met.
6.10 75-mL RESERVOIRS PLUS ADAPTERS - Available from J. T. Baker, Cat.
No. 7120-03 and Cat. No. 7122-00.
552.'1-7
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6.11 GRADUATED CONICAL CENTRIFUGE TUBES WITH TEFLON-LINED SCREW CAPS (15
mL).
6.12 SCREW CAP CULTURE TUBES — Suggested size 13 x 100 mm.
6.13 BLOCK HEATER — Capable of holding screw cap culture tubes In Sect.
6.12.
6.14 VORTEX MIXER
7. REAGENTS AND STANDARDS
7.1 REAGENT WATER — Reagent water is defined as a water in which an
Interference Is not observed at the MDL of each analyte of Interest.
7.1.1 A Milllpore Super-Q water system or its equivalent may be
used to generate deionized reagent water. Distilled..water
that has been passed through granular charcoal may also be
suitable.
7.1.2 Test reagent water each day it is used by analyzing accord-
ing to Sect. 11.
7.2
7.3
7.4
7.5
7.6
7.7
7.8
METHANOL -- Pesticide quality or equivalent.
METHYL-TERT-BUTYL ETHER -- Nanograde, redistilled in glass if
necessary. Ethers must be demonstrated to be free of peroxides.
One test kit (EM Quant Test Strips), is available from EM Science,
Gibbstown, NJ. Procedures for removing peroxides from the ether are
provided with the test strips. Ethers must be periodically tested
(at least monthly) for peroxide formation during use. Any reliable
test kit may be used.
SODIUM SULFATE — (ACS) granular, anhydrous. Heat in a shallow tray
at 400°C for a minimum of 4 hr to remove phthalates and other
interfering organic substances. Alternatively, extract with methy-
lene chloride in a Soxhlet apparatus for 48 hr.
SODIUM HYDROXIDE (NaOH), IN — Dissolve 4 g ACS grade in reagent
water in a 100-mL volumetric flask and dilute to the line.
1,2,3-TRICHLOROPROPANE, 99+% — For use as the internal standard.
2-BROMOPROPIONIC ACID — For use as a surrogate compound.
10X Na?S04/H20 (BY WEIGHT) SOLUTION — Dissolve lOg NazS04 in 90 g
reagent water.
7.9 10X H2S04/MeOH SOLUTION — Prepare a solution containing 10 mL H2S04
in 90 mL methanol.
552.1-8
-------
7.10 IN HCl/MeOH — Prepare a solution containing 8.25 ml HC1 (ACS grade)
with 91.75 ml methanol.
7.11 AG-1-X8 ANION EXCHANGE RESIN - Rinse resin with three consecutive
500-mL aliquots of deionized water and store in deionized water.
Available from Biorad, Richmond, CA.
7.12 ACETONE — ACS reagent grade or equivalent.
7.13 AMMONIUM CHLORIDE — ACS reagent grade or equivalent.
7.14 SODIUM SULFITE — ACS reagent grade or equivalent.
7.15 STOCK STANDARD SOLUTIONS
7.15.1 Analytes and Surrogates (Table 1) — Prepare at 1 to 5 mg/mL
in MTBE.
7.15.2 Internal Standard Fortifying Solution — Prepare a solution
of 1,2,3-trichloropropane at 1 mg/mL by adding 36 j*L of the
neat material (Sect. 7.6) to 50 ml of MTBE. From this stock
standard solution, prepare a primary dilution standard at 10
mg/L by the addition of 1 ml to 100 ml MTBE.
7.15.3 Surrogate Standard Fortifying Solution — Prepare a surro-
gate stock standard solution of 2-bromopropionic acid at a
concentration of 1 mg/mL by accurately weighing approximate-
ly 10 mg of 2-bromopropionic acid, transferring it to a 10-
mL volumetric, and diluting to the mark with MTBE. Prepare
a primary dilution standard at a concentration of 2.5 0g/mL
by diluting 250 pL of the stock standard to 100 ml with
methanol.
8. SAMPLE COLLECTION. PRESERVATION AND STORAGE
8.1 Grab samples must be collected in accordance with conventional
sampling practices (9) using amber glass containers with TFE-lined
screw-caps and capacities in excess of 100 mL.
8.1.1 Prior to shipment to the field, to combine residual chlo-
rine, add crystalline ammonium chloride (NH4C1) to the
sample container in an amount to produce a concentration of
100 mg/L in the sample. Alternatively, add 1.0 mL of a
10 mg/mL aqueous solution of NH4C1 to the sample bottle for
each 100 mL of sample bottle capacity Immediately prior to
sample collection. Granular ammonium chloride may also be
added directly to the sample bottle.
8.1.2 After collecting the sample in the bottle containing the
dechlorination reagent, seal the bottle and agitate for 1
min.
552.1-9
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8.1.3
8.1.4
Samples must be iced or refrigerated at 4°C and maintained
at these conditions away from light until extraction.
Holding studies performed to date have suggested that, in
samples dechlorinated with NH,C1, the analytes are stable
for up to 28 days. Since stability may be matrix dependent,
the analyst should verify that the prescribed preservation
technique is suitable for the samples under study.
Extract concentrates (Sect. 11.3.6) should be stored at 4°C
or less away from light in glass vials with Teflon-lined
caps. Extracts should be analyzed within 48 hrs following
preparation.
9. QUALITY CONTROL
9.1 Minimum quality control (QC) requirements are initial demonstration
of laboratory capability, determination of surrogate compound
recoveries in each sample and blank, monitoring internal standard
peak area or height in each sample and blank, analysis of laboratory
reagent blanks, laboratory fortified blanks, laboratory fortified
sample matrices, and QC samples. Additional QC practices are
recommended.
9.2 LABORATORY REAGENT BLANKS (LRB) - Before processing any samples,
the analyst must analyze at least one LRB to demonstrate that all
glassware and reagent interferences are under control. In addition,
each time a set of samples is extracted or reagents are changed, a
LRB must be analyzed. If within the retention time window (Sect.
11.4.4) of any analyte, the LRB produces an interference signifi-
cantly in excess of that anticipated (Sect. 4.1.1), determine the
source of contamination and eliminate the interference before
processing samples.
9.3 INITIAL DEMONSTRATION OF CAPABILITY
9.3.1 Select a representative fortified concentration for each of
the target analytes. Concentrations near level 2 (Table 4)
are recommended. Prepare 4 to 7 replicate laboratory forti-
fied blanks by adding an appropriate aliquot of the primary
dilution standard or another certified quality control
sample. Be sure to add the internal standard, 1,2,3-tri-
chloropropane, and the surrogate compound, 2 bromopropionic
acid, to these samples (See Sect. 11). Analyze the LFBs
according to the method beginning in Sect. 11 and calculate
mean recoveries and standard deviation for each analyte.
9.3.2 Calculate the mean percent recovery, the standard deviation
of the recoveries, and the MDL (10). For each analyte, the
mean recovery value, expressed as a percentage of the true
value, must fall in the range of 70-130% and the standard
deviation should be less than 30%. For those compounds that
meet these criteria, performance is considered acceptable
552.1-10
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and sample analysis may begin. For those compounds that
fall these criteria, this procedure must be repeated using a
minimum of four fresh samples until satisfactory performance
has been demonstrated. Maintain this data on file to demon-
strate Initial capabilities.
9.3.3 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. As laboratory personnel gain experience with this
method, the quality of data should improve beyond those re-
quired here.
9.3.4 The analyst is permitted to modify GC columns, GC condi-
tions, detectors, extraction techniques, concentration
techniques (i.e., evaporation techniques), Internal standard
or surrogate compounds. Each time such method modifications
are made, the analyst must repeat the procedures In Sect.
9.3.1 and also analyze a laboratory fortified matrix sample.
9.4 ASSESSING SURROGATE RECOVERY
9.4.1
9.4.2
When surrogate recovery from a sample or blank Is < 70% or
> 130X, check (1) calculations to locate possible errors,
(2) standard solutions for degradation, (3) contamination,
and (4) instrument performance. If those steps do not
reveal the cause of the problem, reanalyze the extract.
If the extract reanalysis fails the 70-130% recovery crite-
rion, the problem must be identified and corrected before
continuing. It may be necessary to extract another aliquot
of sample.
9.4.3
If the extract reanalysis meets the surrogate recovery
criterion, report only data for the reanalyzed extract.
sample extract continues to fail the recovery criterion,
report all data for that sample as suspect.
If
9.4.4
Develop and maintain control charts on surrogate recovery as
described 1n Sect. 9.6.2. Charting of surrogate recoveries
1s an especially valuable activity, since these are present
In every sample and the analytical results will form a
significant record of data quality.
9.5 ASSESSING THE INTERNAL STANDARD
9.5.1 When using the Internal standard calibration procedure
prescribed In this method, the analyst is expected to moni-
tor the IS response (peak area or peak height) of all sam-
ples during each analysis day. The IS response for any
sample chromatogram should not deviate from the dally cali-
bration standard IS response by more than 30%.
552.1-11
-------
9.5.2 If > 30% deviation occurs with an individual extract, opti-
mize instrument performance and inject a second aliquot of
that extract.
9.5.2.1 If the reinjected aliquot produces an acceptable
internal standard response, report results for
that aliquot.
9.5.2.2 If a deviation of greater than 30% is obtained for
the reinjected extract, analysis of the samples
should be repeated beginning with Sect. 11, pro-
vided the sample is still available. Otherwise,
report results obtained from the reinjected ex-
tract, but annotate as suspect.
9.5.3 If consecutive samples fail the IS response acceptance
criteria, immediately analyze a medium calibration standard.
9.5.3.1 If the calibration standard provides a response
factor (RF) within 20% of the predicted value,
then follow procedures itemized in Sect. 9.5.2 for
each sample failing the IS response criterion.
9.5.3.2 If the check standard provides a response factor
which deviates more than 20% of the predicted
value, then the analyst must recalibrate (Sect.
10).
9.6 LABORATORY FORTIFIED BLANK
9.6.1 The laboratory must analyze at least one laboratory forti-
fied blank (LFB) sample with every 20 samples or one per
sample set (all samples extracted within a 24-hr period),
whichever is greater. Fortified concentrations near level 2
(Table 4) are recommended. Calculate percent recovery (R).
If the recovery of any analyte falls outside the control
limits (see Sect. 9.6.2), that analyte is judged out of
control, and the source of the problem should be identified
and resolved before continuing analyses.
9.6.2 Prepare control charts based on mean upper and lower control
limits, R ± 3 SR. The initial demonstration of capability
(Sect. 9.3) establishes the initial limits. After each 4-6
new recovery measurements, recalculate R and S. using all
the data, and construct new control limits. When the total
number of data points reach 20, update the control limits by
calculating R and SR using only the most recent 20 data
points. At least quarterly, replicates of LFBs should be
analyzed to determine the precision of the laboratory mea-
surements. Add these results to the ongoing control charts
to document data quality.
552.1-12
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9.7 LABORATORY FORTIFIED SAMPLE MATRIX
9.7.1 Chlorinated water supplies will usually contain significant
background concentrations of several method analytes, espe-
cially dichloroacetic acid (DCAA) and trichloroacetic acid
(TCAA). The concentrations of these acids may be equal to
or greater than the fortified concentrations. Table 6
illustrates the relatively poor accuracy and precision which
may be anticipated when a large background must be subtract-
ed. The water supply used in the development of this method
contained only moderate concentrations of DCAA and TCAA.
For many supplies, the concentrations may be so high that
fortification may lead to a final extract with instrumental
responses exceeding the linear range of the electron capture
detector. If this occurs, the extract must be diluted. In
spite of these problems, sample sources should be fortified
and analyzed as described below. Poor accuracies and high
precisions across all analytes likely indicate the presence
of interfering ions, especially sulfate, and the requirement
for sample dilution.
9.7.2 The laboratory must add known concentrations of analytes to
a minimum of 10% of samples or one sample per sample set,
whichever Is greater. The concentrations should be equal to
or greater than the background concentrations in the sample
selected for fortification. Ideally, the concentration
should be the same as that used for the laboratory fortified
blank (Sect. 9.6). Over time, samples from all routine
sample sources should be fortified.
9.7.3 Calculate the mean percent recovery, R, of the concentration
for each analyte, after correcting the total mean measured
concentration, A, from the fortified sample for the back-
ground concentration, B, measured in the unfortified sample,
i.e.:
R - 100 (A - B) / C,
where C Is the fortifying concentration. Compare these
values to control limits appropriate for reagent water data
collected in the same fashion (Sect. 9.6).
9.7.4 If the analysis of the unfortified sample reveals the ab-
sence of measurable background concentrations, and the added
concentrations are those specified in Sect. 9.6, then the
appropriate control limits would be the acceptance limits in
Sect. 9.6.
9.7.5 If the sample contains measurable background concentrations
of analytes, calculate mean recovery of the fortified con-
centration, R, for each such analyte after correcting for
the background concentration (Sect. 9.7.3). Compare these
552.1-13.
-------
values to reagent water recovery data, R*, at comparable
fortified concentrations from Tables 2, 4, and 5. Results
are considered comparable if the measured recoveries fall
within the range,
R ± 3SC,
where Sc is the estimated percent relative standard devia-
tion in the measurement of the fortified concentration. By
contrast to the measurement of recoveries in reagent water
(Sect. 9.6.2) or matrix samples without background (Sect.
9.7.3), the relative standard deviation, Sc, must be ex-
pressed as the statistical sum of variation from two
sources, the measurement of the total concentration as well
as the measurement of background concentration. In this
case, variances, defined as S , are additive and Sc can be
expressed as,
or
(Sa2
Sb2)1/2,
where S and Sb are the percent relative standard deviations
of the total measured concentration and the background
concentration respectively. The value of S may be estimat-
ed from the mean measurement of A above or from data at
comparable concentrations from Tables 2, 4, and 5. Like-
wise, Sb can be measured from repetitive measurements of the
background concentration or estimated from comparable con-
centration data from Tables 2, 4, and 5.
9.7.6 If the recovery of any such analyte falls outside the desig-
nated range, and the laboratory performance for that analyte
is shown to be in control (Sect. 9.6), the recovery problem
encountered with the fortified 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.
9.8 QUALITY CONTROL SAMPLE (QCS) -- At least quarterly, analyze a QCS
from an external source. If measured analyte concentrations are not
of acceptable accuracy, check the entire analytical procedure to
locate and correct the problem source.
9.9 The laboratory may adapt additional QC 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
552.1-1
-------
blanks may be used to assess contamination of samples under site
conditions, transportation and storage.
10. CALIBRATION AND STANDARDIZATION
10.1 Establish GC operating parameters equivalent to the suggested
specifications in Table 1. The GC system must be calibrated using
the internal standard (IS) technique. Other columns or conditions
may be used if equivalent or better performance can be demonstrated.
10.2 INTERNAL STANDARD CALIBRATION PROCEDURE -- This approach requires
the analyst to select one or more internal standards which are
compatible In analytical behavior with the method analytes. For the
single laboratory precision and accuracy data reported in Tables
2-9, one internal standard, 1,2,3-trichloropropane, was used as a
concentration of 0.4 ng/ml in the final 5.0-mL concentrate.
10.2.1 Prepare separate stock standard solutions for each analyte
of interest at a concentration of 1-5 mg/mL in MTBE. Method
analytes may be obtained as neat materials or ampulized
solutions (> 99% purity) from a number of commercial suppli-
ers.
10.2.2 Prepare primary dilution standard solutions by combining and
diluting stock standard solutions with methanol. As a
guideline to the analyst, the primary dilution standard
solution used in the validation of this method is described
here. Stock standard solutions were prepared in the 1-2
mg/mL range for all analytes and the surrogate. Aliquots of
each stock standard solution (approximately 50-250 /zL) were
added to 100-mL methanol to yield a primary dilution stan-
dard containing the following approximate concentrations of
analytes:
Honochloroacetic acid
Monobromoacetic add
Dalapon
Dichloroacetic acid
2-Bromopropionic acid
Trichloroacetic acid
Bromochloroacetic acid
Dibromoacetic acid
Concentration, ua/ml
3
2
2
3
1
1
2
1
The primary dilution standards are used to prepare calibra-
tion standards, which comprise at least three concentration
levels (optimally five) of each analyte with the lowest
standard being at or near the MOL of each analyte. The
concentrations of the other standards should define a range
containing the expected sample concentrations or the working
range of the detector.
552.1-15
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10.2.2.1 Calibration standards — Calibration is performed
by extracting procedural standards, i.e.; forti-
fied reagent water. A five-point calibration
curve may be prepared by fortifying a 100- ml re-
agent water samples at pH 5 with 20, 50, 100, 250,
and 500 til of the primary dilution standard pre-
pared above. Alternatively, three levels of cali-
bration solutions may be prepared. Analyze each
calibration standard in triplicate according to
the procedure outlined in Sect. 11. In addition,
a reagent water blank must be analyzed in tripli-
cate.
10.2.3 Include the surrogate analyte, 2-bromopropionic acid,
within the calibration standards prepared in Sect. 10.2.2.
10.2.4 Inject 2 0L of each standard and calculate the relative
response for each analyte (RRa) using the equation:
• *^** !•
where A, is the peak area of the analyte.
A{8 the peak area of the internal standard.
Generate a calibration curve of RR. versus analyte concen-
tration of the standards expressed in equivalent pg/L in the
original aqueous sample. The working calibration curve must
be verified daily by measurement of one or more calibration
standards. If the response for any analyte falls outside
the predicted response by more than 15%, the calibration
check must be repeated using a freshly prepared calibration
standard. Should the retest fail, a new calibration curve
must be generated.
A data system may be used to collect the chromatographic
data, calculate response factors, and calculate linear or
second order calibration curves.
10.2.5
10.2.6
11. PROCEDURE
11.1 PREPARATION AND CONDITIONING OF EXTRACTION COLUMNS
11.1.1 Preparation — Place 1 mL liquid-solid extraction cartridges
(Sect. 6.9) onto the vacuum manifold. Place frits into the
tubes and push down to place them flat on the bottom. Add
the AG-1-X8 resin solution dropwise to the tubes with a
Pasteur pipet until there is a solid layer of resin 10 mm in
height. Add reagent water and apply vacuum to settle out
the suspended resin particles. Do not allow the resin to go
dry. At this point extraction of samples can begin or the
columns can be stored for later use by maintaining the resin
under water and sealing the top with aluminum foil.
552.1-16
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11.1.2 Conditioning -- Attach adapters and 75-mL reservoirs to the
liquid-solid extraction cartridges. To condition the col-
umns, add to the reservoirs and pass the following series of
solvents in 10-mL aliquots through the resin under vacuum:
methanol, reagent water, 1 M HCl/MeOH, reagent water, 1 H
NaOH, and reagent water. The conditioning solvents should
pass through the resin at the rate of = 2 mL/min. without
allowing the resin bed to dry and the sample should be added
(Sect. 11.2.3) immediately after the last reagent water
aliquot.
11.2 SAMPLE EXTRACTION AND ELUTION
11.2.1 Remove the samples from storage (Sect. 8.1.3) and allow them
to equilibrate to room temperature.
11.2.2 Adjust the pH of a 100-mL sample to 5 ± 0.5 using 1:2 H2S04
water and check the pH with a pH meter or narrow range pH
paper.
11.2.3 Add 250 pi of the surrogate primary dilution standard (Sect.
7.15.3) to each sample
11.2.4 Transfer the 100-mL sample to the reservoir and apply a
vacuum to extract the sample at the rate of * 2 mL/min.
11.2.5 Once the sample has completely passed through the column add
10 mL MeOH to dry the resin.
11.2.6 Remove the reservoirs and adapters, disassemble the vacuum
manifold and position screw cap culture tubes (Sect. 6.12)
under the columns to be eluted. Reassemble the vacuum
manifold, add 4 mL 10% H2S04/methanol to the column and
elute at the rate of approximately 1.5 mL/min. Turn off the
vacuum and remove the culture tubes containing the eluants.
11.3 SOLVENT PARTITION
11.3.1 Add 2.5 mL MTBE to each eluant and agitate in the vortex
mixer at a low setting for about 5 sec.
11.3.2 Place the capped culture tubes in the heating block (Sect.
6.13) at 50°C and maintain for 1 hr. At this stage, quanti-
tative methyl ation of all method analytes is attained.
11.3.3 Remove the culture tubes from the heating block and add to
each tube 10 mL of 10% by weight of sodium sulfate in re-
agent water (Sect. 7.8). Agitate each solution for 5-10 sec
In the vortex mixer at a high setting.
11.3.4 Allow the phases to separate for approximately 5 min. Trans-
fer the upper MTBE layer to a 15-mL graduated conical cen-
552.1-17
-------
11.3.5
trifuge tube (Sect. 6.11) with a pasteur pipet. Repeat the
extraction two more times with approximately 1 ml HTBE each
time. Combine the MTBE sample extracts In the graduated
centrifuge tube.
Add 200 fil of the Internal standard fortifying solution
(Sect. 7.15.2) to each extract and add MTBE to each to a
final volume of 5 ml.
11.3.6 Transfer a portion of each extract to a vial and analyze
using GC-ECD. A duplicate vial should be filled from excess
extract. Analyze the samples as soon as possible. The
sample extract may be stored up to 48 hr If kept at 4°C or
less away from light In glass vials with Teflon-lined caps.
11.4 GAS CHROMATOGRAPHY
11.4.1
Table 1 summarizes recommended GC operating conditions and
retention times observed using this method. Figure 1 illus-
trates the performance of the recommended column with the
method analytes. Other GC columns, chromatographic condi-
tions, or detectors may be used if the requirements of Sect.
9.3 are met.
11.4.2
11.4.3
11.4.4
Calibrate the system daily as described in Sect. 10.
standards and extracts must be in MTBE.
The
Inject 2 0L of the sample extract.
peak size in area units.
Record the resulting
11.4.5
The width of the retention time window used to make Identi-
fications should be based upon measurements of actual reten-
tion 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.
If the response for the peak exceeds the working range of
the system, dilute the extract and reanalyze.
12. DATA ANALYSIS AND CALCULATIONS
12.1 Calculate analyte concentrations in the sample and reagent blanks
from the response for the analyte relative to the internal standard
(RR.) using the equation in Sect. 10.2.4.
12.2 For samples processed as part of a set where recoveries falls
outside of the control limits established in Sect. 9, results for
the affected analytes must be labeled as suspect.
552;1-18
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13.
MEPPD
13.1 In a single laboratory (EMSL-Cincinnati) , recovery and precision data
were obtained at three corcentrations in reagent water (Tables 2, 4, and
5) . In addition, recovery and precision data were obtained at a medium
nitration for high ionic strength reagent water (Table 3) ,
14.
15.
16.
dechlorinated tap water, high humectant ground water, and an ozonated
surface water (Tables 6-9). The MDL (10} data are given in Table 2.
HREVHfi'XOf
14.1 This method utilizes the new LSE technology which requires the use of
very small quantities of organic solvents. This feature eliminates the
hazards involved with the use of large volumes of potentially harmful
organic solvents needed for conventional liquid-liquid extractions.
This method also uses acidic methanol as the derivatizing reagent in
place of the highly toxic diazomethane. These features make this method
much safer for use by the analyst in the laboratory and much less
harmful to the environment.
14.2 For information about pollution prevention that may be applicable to
laboratory operations, consult "Less is Better: laboratory Chemical
Management for Waste Reduction11 available from the American Chemical
Society's Department of Government. Relations arse! Science Policy, 1155
16th Street N.W., Washington, D.C. 20036.
15.1 It is the laboratory's responsibility to comply with all federal, state
and local regulations governing the waste management, particularly the
hazardous waste identification rules and land disposal restrictions. It
is also the laboratory's responsibility to protect the air, water, and
land by minimizing and controlling all releases from fume hoods and
bench operations. Compliance is also required with any sewage discharge
permits and regulations. For further information on waste management,
consult "The Waste Management Manual for Laboratory Personnel," «!«"
available from the American Chemical Society at the address in Section
14.2.
1.
Hbdgeson, J. W. , Collins, J. D. , and Becker, D. A. , "Advanced Techniques
for the Measurement of Acidic Herbicides and Disinfection Byproducts in
Aqueous Samples," Proceedings of the 14th Annual EPA Conference on
Analysis of Pollutants in the Environment, Norfolk, VA. , May 8-9, 1991.
Office of Water Publication No. 821-R-92-001, U.S. Fjwironmental
Protection Agency, Washington, DC, pp 165-194.
552.1-19
-------
2. Uden, P.C. and Miller, J.W., J. Am. Water Works Assoc. 75, 1983, pp.
524-527.
3. Fair. P.S., Barth, R.C., Flesch, J. J. and Brass, H. "Measurement of
Disinfection By-products in Chlorinated Drinking Water," Proceedings
Water Quality Technology Conference (WQTC-15), Baltimore, Maryland,
November 15-20, 1987, American Water Works Association, Denver, CO,
pp. 339-353.
4. 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.
5. "Carcinogens-Working with Carcinogens," Publication No. 77-206,
Department of Health, Education, and Welfare, Public Health Service,
Center for Disease Control, National Institute of Occupational Safety
and Health, Atlanta, GA, August 1977.
6. "OSHA Safety and Health Standards, General Industry," (29CFR1910),
OSHA 2206, Occupational Safety and Health Administration, Washington,
D.C. Revised January 1976.
7. "Safety In Academic Chemistrv Laboratories," 3rd Edition, American
rhami^>i.. Society Publication, Committee on Chemical Safety, Washing
ton, D.C., 1979.
8. Hodgeson, J.W. and Cohen, A.L. and Collins, J.D., "Analytical Methods
for Measuring Organic Chlorination By-products," Proceedings Water
Quality Technology Conference (WQTC-16), St. Louis, MO, Nov. 13-17,
1988, American Water Works Association, Denver, CO, pp. 981-1001.
9. ASTM Annual Book of Standards, Part 31, D3370, "Standard Practice for
Sampling Water," American Society for Testing and Materials, Philadel-
phia, PA, p. 76, 1980.
10. Glaser, J. A., Foerst, D. L., McKee, G. D., Quave, S. A. and Budde, W.
L., Environ. Sci. Techno!. 15, 1981, pp. 1426-1435.
552.1-20
-------
17. TABLES, DIAGRAMS, FLOWCHARTS, AND VALIDATION DATA
TABLE 1. RETENTION DATA AND CHRONATOGRAPHIC CONDITIONS
Analyte
Monochloroacetic Add (MCAA)
Monobromoacetic Add (MBAA)
Dal apon
Dichloroacetic Add (DCAA)
2-Bromoprop ionic add (b)
Trichloroacetlc Acid (TCAA)
1,2,3-Trlchloropropane (a)
Bromochloroacetic Acid (BCAA)
Dibromoacetic Acid (DBAA)
Retention Time.
Column A
5.16
7.77
8.15
8.37
8.80
11.43
12.62
12.92
15.50
m1n.
Column B
9.44
11.97
11.97
11.61
12.60
13.34
12.91
14.20
16.03
Column A: DB-1701, 30 m x 0.32 mm i.d., 0.25 |im film thickness,
Injector Temp. - 200°C, Detector Temp. • 260°C, Helium
Linear Velocity - 27 cm/sec, Splitless injection with 30 s
delay
Program: Hold at 50°C for 10 min, to 200°C at 10°C/min. and hold 5
min., to 230'C at 10°C/min. and hold 5 min.
Column B: DB-210, 30 m x 0.32 mm i.d., 0.50 pi film thickness,
Injector Temp. - 200°C, Detector Temp. * 260°C, Linear
Helium Flow • 25 cm/sec, splitless injection with 30 s
delay.
Program: Hold at 50°C for 10 min., to 200°< at 10°C/min and hold 5
min., to 230° at 10°C/min. and hold 5 min.
(a) Internal Standard
(b) Surrogate Compound
552.1-21
-------
TABLE 2. ANALYTE RECOVERY AND PRECISION DATA
AND METHOD DETECTION LIMITS"
LEVEL 1 IN REAGENT WATER
Fortified
Cone.
Analyte pg/L
Monochloroacetlc Add
Honobromoacetic Add
Dlchloroacetic Add
2-Bromoprop1on1c Ac1db
Trlchloroacetlc Add
Bromochloroacetlc acid
D1bromoacet1c Add
Dalapon
1.5
1.0
1.5
0.05
0.50
1.0
0.50
1.0
Mean
Meas.
Cone.
M9/L
1.47
0.73
1.65
0.47
0.30
0.75
0.29
0.81
Std.
Dev.
W/L
0.07
0.08
0.14
0.03
0.02
0.03
0.03
0.10
Rel.
Std.
Dev., %
4.6
7.9
7,7
5.6
4.0
3.4
6.4
12
Mean
Recovery
%
98
73
110
94
60
75
58
81
Method
Detection
Limit
M9/L
0.21
0.24
0.45
0.08
0.07
0.10
0.09
0.32
"Produced by analysis of seven allquots of fortified reagent water (Reference 10).
b Surrogate Compound
552'. 1-22
-------
TABLE 3. RECOVERY AND PRECISION DATA IN HIGH
IONIC STRENGTH MATERS
MEAN RECOVERY ± RSD8
Fortified
Cone.
Analyte pg/l
Monochloroacetic Acid
Monobromoacetic Acid
Dichloroacetic Acid
2-Bromoprop ionic Acid
Trichloroacetic Acid
Bromochloroacetic Acid
Dibromoacetic Acid
Dal apon
7.
5.
7.
2.
2.
5.
2.
5.
5
0
5
5
5
0
5
0
Reagent Reagent Water +
Water (RW) 500 mg/L Na2S04b
109 ±
83 ±
107 ±
108 ±
101 i
101 ±
93 ±
93 ±
1.5
18
3.6
1.8
0.4
2.6
1.9
1.9
5.0 ± 10
59 ± 2.4
32 ± 0.3
8 ± 3.0
85 ± 0.7
40 ± 22
57 ± 5.3
Reagent Water +
400 mg/L NaClfa
46
50
114
137
64
107
89
99
±
±
±
±
±
±
±
±
10
13
0
2
11
3
5
1
.1
.1
.5
.0
.7
a Based on the analysis of three replicate samples.
b Molar concentration of added salt 1s 3.7 tnM in both cases.
552,1-23
-------
TABLE 4. ANALYTE RECOVERY AND PRECISION DATA*
LEVEL 2 IN REAGENT WATER
Analyte
Monochloroacetlc Add
Monobromoacetic Add
Dichloroacetlc Add
2-Bromopropionic Ac1db
Trlchloroacetlc Add
Bromochloro acetic Add
Dibromoacetlc Add
Dal apon
Fortified
Cone.
M9/L
7.5
5.0
7.5
2.5
2.5
5.0
2.5
5.0
Mean
Heas.
Cone.
M9/L
7.73
3.95
8.06
2.57
2.32
5.22
2.41
4.03
Std.
Dev.
H9/L
0.18
0.65
0.16
0.06
0.14
0.12
0.09
0.36
Rel.
Std.
Dev., X
2.3
16
2.0
2.4
5.8
2.2
3.4
7.5
Mean
Recovery
%
103
79
108
103
93
104
96
97
* Produced by the analysis of seven aliquots of fortified reagent water.
b Surrogate Compound
552.1-24
-------
TABLE 5. ANALYTE RECOVERY AND PRECISION DATA*
LEVEL 3 IN REAGENT WATER
Analyte
Monochloroacetlc Add
Monobromoacetlc Add
Dlchloroacetic Add
2-Bromopropionic Add
Trichloroacetlc Add
Bromochloroacetlc Add
D1bromoacet1c Add
Dal apon
Fortified
Cone.
W/L
15.0
10.0
15.0
5.0
5.0
10.0
5.0
10.0
Mean
Meas.
Cone.
W/L
14.5
7.82
15.1
4.98
4.89
10.3
4.85
9.02
Std.
Dev.
M/L
0.15
0.68
6.09
0.08
0.07
0.25
0.04
0.16
Rel.
Std.
Dev., %
1.0
8.4
0.6
1.5
1.4
2.4
0.7
1.8
Mean
Recovery
%
99
78
101
100
98
103
97
90
' Produced by the analysis of seven aliquots of fortified reagent water.
552.1-25
-------
TABLE 6. ANALYTE RECOVERY AND PRECISION DATA1
DECHLORINATED TAP WATER
Fortified
Cone.
Analyte ftg/l
Monochloroacetlc Acid
Honobromoacetic Acid
Dlchloroacetic Acid
2-Bromoproplonic Ac1dc
THchloroacetic Acid
Brofflochloroacetic Acid
Dibromoacetic Acid
Dal apon
7.5
5.0
7.5
7.5
2.5
5.0
2.5
5.0
Meanb
Meas.
Cone.
MI/L
5.70
4.57
5.62
2.22
1.48
5.70
2.42
4.69
Std.
Dev.
W/L
0.63
0.45
0.76
0.16
0.42
0.92
0.13
0.21
Rel.
Std.
Dev., X
11
9.8
14
7.2
28
16
5.4
4.5
Mean
Recovery
%
76
91
75
89
59
114
97
94
a Produced by the analysis of seven aliquots of fortified dechlorinated tap water.
b Significant background concentrations (> 5-15 M9/L) have been subtracted from these
values for dichloroacetic add, trichloroacetic acid, bromochloroacetic acid, and
dibromoacetic acid.
c Surrogate Compound
552.1-26
-------
TABLE 7. ANALYTE RECOVERY AND PRECISION DATA*
HIGH HUMIC CONTENT GROUND WATER
Analyte
Monochl oroacet i c Ac 1 d
Monobromoacetlc Acid
Dichl oroacet 1c Add
2-Bromoprop1on1c Ac1db
Trichl oroacet ic Acid
Bromochl oroacet 1c Acid
Dlbronoacetlc Add
Dalapon
Fortified
Cone.
W/L
7.5
5.0
7.5
2.5
2.5
5.0
2.5
5.0
Mean
Meas.
Cone.
M9/L
3.55
2.21
7.60
1.83
2.37
5.53
2.58
4.92
Std.
Dev.
A9/L
0.32
0.21
0.08
0.09
0.12
0.16
0.13
Q.29
Rel.
Std.
Dev., %
8.9
11
1.1
4.9
5.1
2.9
5.0
6.0
Mean
Recovery
X
47
44
101
73
95
111
103
90
* Produced by the analysis of seven aliquots of fortified high humic content ground
water.
b Surrogate Compound
552.1-27
-------
TABLE 8. ANALYTE RECOVERY AND PRECISION DATA8
HIGH HUMIC CONTENT GROUND WATER DILUTED 1:5
Analyte
Monochloroacetic Acid
Monobromoacetlc Add
Dichloroacetic Acid
2-Bromopropionic Acidb
Trichloroacetic Acid
Bromochloroacetic Acid
Dibromoacetic Acid
Dal apon
Fortified
Cone.
M/L
1.5
1.0
1.5
0.5
0.5
1.0
0.5
1.0
Mean
Meas.
Cone.
0g/L
1.50
0.97
1.89
0.49
0.28
0.43
0.30
0.88
Std.
Dev.
W/L
0.17
0.06
0.16
0.01
0.03
0.07
0.02
0.12
Rel.
Std.
Dev., %
11
6.2
8.5
2.0
11
16
6.7
14
Mean
Recovery
%
100
97
126
98
56
43
60
88
* Produced by the analysis of seven aliquots of fortified high hunric content ground
water diluted 1:5.
b Surrogate Compound
552.1-28
-------
TABLE 9. ANALYTE RECOVERY AND PRECISION DATA*
OZONATED RIVER WATER
Analyte
Honochloroacetic Acid
Monobrorao acetic Acid
Dichlorpacetic Acid
2-Bromopropionic Acidb
Trichloroacetic Acid
Bromochloroacetic Acid
Dibromoacetic Acid
Oalapon
Fortified
Cone.
W/L
7.5
5.0
7.5
2.5
2.5
5.0
2.5
5.0
Mean
Meas.
Cone.
M9/L
6.22
4.28
7.09
2.31
2.65
5.20
2.36
5.08
Std.
Dev.
ng/i
0.91
0.34
0.22
0.09
0.13
0.18
0.09
0.17
Rel.
Std.
Dev., X
15
7.9
3.1
3.7
4.9
3.5
3.8
3.4
Mean
Recovery
%
83
86
94
92
106
104
94
102-
" Produced by the analysis of seven aliquots of fortified ozonated river water.
b Surrogate Compound
552.1-29
-------
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-------
METHOD.552.2
DETERMINATION OF HALOACETIC ACIDS AND DALAPON IN DRINKING WATER
BY LIQUID-LIQUID EXTRACTION, DERIVATIZATION AND GAS
CHROMATOGRAPHY WITH ELECTRON CAPTURE DETECTION.
Revision 1.0
J.W. Hodgeson (USEPA), J. Collins and R.E. Earth (Technology Applications
Inc.) - Method 552.0, (1990)
J.W. Hodgeson (USEPA), D. Becker (Technology Applications Inc.) - Method
552.1, (1992)
D.J. Munch, J.W. Munch (USEPA) and A.M. Pawlecki (International Consultants,
Inc.), Method 552.2, Rev. 1.0, (1995)
NATIONAL EXPOSURE RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
552.2-1
-------
METHOD 552.2 DETERMINATION OF HALOACETIC ACIDS AND DALAPON
IN DRINKING MATER BY LIQUID-LIQUID EXTRACTION, DERIVATIZATION
AND GAS CHROMATOGRAPHY WITH ELECTRON CAPTURE DETECTION
1. SCOPE AND APPLICATION
1.1
1.2
1.3
1.4
This is a gas chromatographic (GC) method (1-8) applicable to the
determination of the listed halogenated acetic acids in drinking
water, ground water, raw source water and water at any intermediate
treatment stage. In addition, the chlorinated herbicide, Dalapon,
may be determined using this method.
Analvte
Bromochloroacetic Acid (BCAA)
Bromodichloroacetic Acid (BOCAA)
Chlorodibromoacetic Acid (CDBAA)
Dalapon
Dibromoacetic Acid (DBAA)
Dichloroacetic Acid (DCAA)
Monobromoacetic Acid (MBAA)
Monochl.oroacetic Acid (MCAA)
Tribromoacetic Acid (TBAA)
Trichloroacetic Acid (TCAA)
Chemical Abstract Services
Registry Number
5589-96-3
7113-314-7
5278-95-5
75-99-0
631-64-1
79-43-6
79-08-3
79-11-8
75-96-7
76-03-9
This method is applicable to the determination of the target
analytes over the concentration ranges typically found in drinking
water (1,2,4). Experimentally determined method detection limits
(MDLs) for the above listed analytes are provided in Table 2.
Actual MDLs may vary according to the particular matrix analyzed and
the specific instrumentation employed. The haloacetic acids are
observed ubiquitously in chlorinated drinking water supplies at
concentrations ranging from <1 to >50 /*g/L.
This method is designed for analysts skilled in liquid-liquid
extractions, derivatization procedures and the use of GC and
interpretation of gas chromatograms. Each analyst must demonstrate
the ability to generate acceptable results with this method using
the procedure described in Section 9.3.
When this method is used for the analyses of waters from unfamiliar
sources, it is strongly recommended that analyte identifications be
confirmed by GC using a dissimilar column or by GC/MS if
concentrations are sufficient.
2. SUMMARY OF METHOD
2.1 A 40-mL volume of sample is adjusted to pH <0.5 and extracted with
4-mL of methyl-tert-butyl-ether (MTBE). The haloacetic acids that
have been partitioned into the organic phase are then converted to
552.2-2
-------
their methyl esters by the addition of acidic methanol followed by
slight heating. The acidic extract 1s neutralized by a back-
extraction with a saturated solution of sodium bicarbonate and the
target analytes are identified and measured by capillary column gas
chromatography using an electron capture detector (GC/ECD).
Analytes are quantitated using procedural standard calibration.
3. DEFINITIONS
3.1 INTERNAL STANDARD (IS) — A pure analyte(s) added to a sample,
extract, or standard solution in known amount(s) and used to measure
the relative responses of other method analytes and surrogates that
are components of the same sample or solution. The internal
standard must be an analyte that is not a sample component.
3.2 SURROGATE ANALYTE (SA) — A pure analyte(s), which is extremely
unlikely to be found in any sample, and which is added to a sample
aliquot in known amount(s) before extraction or other processing and
is measured with the same procedures used to measure other sample
components. The purpose of the SA is to monitor method performance
with each sample.
3.3 LABORATORY DUPLICATES (LD1 AND LD2) — Two aliquots of the same
sample designated as such in the laboratory. Each aliquot is
extracted, derivatized and analyzed separately with identical
procedures. Analyses of LD1 and LD2 indicate the precision
associated with laboratory procedures, but not with sample
collection, preservation, or storage procedures.
3.4 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 measure of the precision associated
with sample collection, preservation and storage, as well as with
laboratory procedures.
3.5 LABORATORY REAGENT BLANK (LRB) — An aliquot of reagent water or
other blank matrix that are 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.
3.6 FIELD REAGENT BLANK (FRB) — An aliquot of reagent water or other
blank matrix that is placed in a sample container in the laboratory
.and treated as a sample in all respects, including shipment to the
sampling site, 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.
552.2-3
-------
3.7 LABORATORY FORTIFIED BLANK (LFB) — An aliquot of reagent water or
other blank matrix 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.
3.8 LABORATORY FORTIFIED SAMPLE MATRIX (LFM) -- An aliquot of an
environmental 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.
3.9 STOCK STANDARD SOLUTION (SSS) — A concentrated solution containing
one or more method analytes prepared in the laboratory using assayed
reference materials or purchased from a reputable commercial source.
3.10 PRIMARY DILUTION STANDARD SOLUTION (PDS) -- 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.
3.11 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.
3.12 QUALITY CONTROL SAMPLE (QCS) — A solution of method analytes of
known concentration which is used to fortify an aliquot of reagent
water or sample matrix. The QCS is obtained from a source external
to the laboratory and different from the source of calibration
standards. It is used to check laboratory performance with
externally prepared test materials.
3.13 LABORATORY PERFORMANCE CHECK SOLUTION (LPC) — A solution of
selected method analytes used to evaluate the performance of the
instrumental system with respect to a defined set of method
criteria.
3.14 METHOD DETECTION LIMIT (MDL) — The minimum concentration of an
analyte that can be identified, measured and reported with 99%
confidence that the analyte concentration is greater than zero.
3.15 MATERIAL SAFETY DATA SHEET (MSDS) -- Written information provided by
vendors concerning a chemical's toxicity, health hazards, physical
properties, fire and reactivity data including storage, spill, and
handling precautions.
552.2-4
-------
3.16 ESTIMATED DETECTION LIMIT (EDL) — Defined as either the MDL or a
level of a compound in a sample yielding a peak in the final extract
with a signal to noise (S/N) ratio of approximately 5, whichever is
greater.
3.17 PROCEDURAL STANDARD CALIBRATION — A calibration method where
aqueous calibration standards are prepared and processed (e.g.
purged, extracted and/or derivatized) in exactly the same manner as
a sample. All steps in the process from addition of sampling
preservatives through instrumental analyses are included in the
calibration. Using procedural standard calibration compensates for
any inefficiencies in the processing procedure.
3.18 CONTINUING CALIBRATION CHECK (CCC) -- A calibration standard con-
taining one or more method analytes, which is analyzed periodically
to verify the accuracy of the existing calibration curves or re-
sponse factors for those analytes.
4. 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 chromatograms. All
reagents and apparatus must be routinely demonstrated to be free
from interferences under the conditions of the analysis by analyzing
laboratory reagent blanks as described in Section 9.5. Subtracting
blank values from sample results is not permitted.
4.1.1 Glassware must be scrupulously cleaned. Clean all glassware
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 water and reagent
water. Drain and heat in an oven or muffle furnace at 400°C
for 1 hr. Do not heat'volumetric ware but instead rinse
three times with HPLC grade or better acetone. Thorough
rinsing with reagent grade acetone may be substituted for the
heating provided method blank analysis confirms no background
interferant contamination is present. Thermally stable
materials such as PCBs may not be eliminated by these treat-
ments. After drying and cooling, store glassware in a clean
environment free of all potential contamination. To prevent
any accumulation of dust or other contaminants, store glass-
ware inverted or capped with aluminum foil. :
4.1.2 The use of high purity reagents and solvents helps to mini-
mize interference problems. Each new bottle of solvent
should be analyzed before use. An interference free solvent
is a solvent containing no peaks yielding data at > MDL
(Table 2) and at the retention times of the analytes of
interest. Purification of solvents by distillation in all-
glass systems may be required.
552.2-5
-------
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.
Routine between-sample rinsing of the sample syringe and associated
equipment with MTBE can minimize sample cross-contamination. After
analysis of a sample containing high concentrations of analytes, one
or more injections of MTBE 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 coex-
tracted from the sample. The extent of matrix interferences will
vary considerably from source to source, depending upon the water
sampled. Analyte identifications should be confirmed using the
confirmation column specified in Table 1 or by GC/MS if the concen-
trations are sufficient.
4.4 Bromochloroacetic acid coelutes with an interferant on the DB-1701
confirmation column. The interferant has been tentatively identi-
fied as dimethyl sulfide. However, because of the difference in
peak shapes, the peak for the ester of BCAA tends to "ride on" the .
interferant peak and quantitative confirmation can be performed by
manual integration that includes only the peak area of the target
ester.
4.5 Methylation using acidic methanol results in a partial decarboxyl-
ation of tribromoacetic acid (8). Therefore a substantial peak for
bromoform will be observed in the chromatograms. Its elution does
not, however, interfere with any other analytes. Furthermore, this
demonstrates the need for procedural standards to establish the
calibration curve by which unknown samples are quantitated.
5. SAFETY
5.1 The toxicity or carcinogenicity of each reagent used in this method
has not been precisely defined; however, each chemical compound must
be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be minimized. The laboratory is
responsible for maintaining a current awareness file of OSHA regula-
tions regarding the safe handling of the chemicals specified in this
method. A reference file of material safety data sheets should also
be made available to all personnel involved in the chemical analy-
sis. Additional references to laboratory safety are available and
have been identified (9-11) for the information of the analyst.
5.2 The toxicity of the extraction solvent, MTBE, has not been well
defined. Susceptible individuals may experience adverse affects
upon skin contact or inhalation of vapors. Therefore protective •
clothing and gloves should be used and MTBE should be used only in a
chemical fume hood or glove box. The same precaution applies to
pure standard materials.
552.2-6
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6. APPARATUS AND EQUIPMENT
6.1 SAMPLE CONTAINERS — Amber glass bottles, approximately 50 mL,
fitted with Teflon-lined screw caps.
6.2 EXTRACTION VIALS — 60 mL clear glass vials with teflon-lined screw
caps.
6.3 VIALS -- Autosampler, 2.0 mL vials with screw or crimp cap and a
teflon-faced seal.
6.4 STANDARD SOLUTION STORAGE CONTAINERS — 10-20 ml amber glass vials
with teflon lined-screw caps.
6.5 GRADUATED CONICAL CENTRIFUGE TUBES WITH TEFLON-LINED SCREW CAPS -
15-mL with graduated 1 mL markings.
6.6 BLOCK HEATER (or SAND. BATH) -- Capable of holding screw cap conical
centrifuge tubes in Section 6.4.
6.7 PASTEUR PIPETS — Glass, disposable.
6.8 PIPETS — 2.0 mL and 4.0 mL, type A, TO, glass.
6.9 VOLUMETRIC FLASKS — 5 ml, 10 mL.
6.10 MICRO SYRINGES — 10 fit, 25 0L, 50 fil, 100 /iL, 250 fil, 500 /d. and
1000 /iL.
6.. 11 BALANCE — analytical, capable of weighing to 0.0001 g.
6.12 GAS CHROMATOGRAPH — Analytical system complete with gas chromato-
graph equipped for electron capture detection, split/splitless
capillary or direct injection, temperature programming, differential
flow control, and with all required accessories including syringes,
analytical columns, gases and strip-chart recorder. A data system
is recommended for measuring peak areas. An autoinjector is recom-
mended for improved precision of analyses. The gases flowing
through the electron capture detector should be vented through the
laboratory fume hood system.
6.13 PRIMARY GC COLUMN -- DB-5.625 [fused silica capillary with chemical-
ly bonded (5% phenylj-methylpolysiloxane)] or equivalent bonded,
fused silica column, 30m x 0.25mm ID, 0.25 pm film thickness.
6.14 CONFIRMATION GC COLUMN — DB-1701 [fused silica capillary with
chemically bonded (14% cyanopropylphenyl)-methylpolysiloxane)] or
equivalent bonded, fused silica column, 30 m x 0.25 mm ID, 0.25 /im
film thickness.
552.2-7
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7. REAGENTS AND STANDARDS
7.1 REAGENT WATER — Reagent water is defined as a water in which an
interference is not observed > to the MDL of each analyte of inter-
est.
7.1.1 A Millipore Super-Q water system or its equivalent may be
used to generate deionized reagent water. Distilled water
that has been passed through granular charcoal may also be
suitable.
7.1.2 Reagent water is monitored through analysis of the labora-
tory reagent blank (Section 9.5).
7.2 SOLVENTS
7.2.1 METHYL-TERT-BUTYL ETHER — High purity, demonstrated to be
free of analytes and interferences, redistilled in glass if
necessary.
7.2.2 METHANOL — High purity, demonstrated to be free of
analytes and interferences.
7.2.3 ACETONE -- High purity, demonstrated to be free of analytes
and interferences.
7.3 REAGENTS
7.3.1 SODIUM SULFATE, Na2S04 — (ACS) granular, anhydrous. If
interferences are observed, it may be necessary to heat the
sodium sulfate in a shallow tray at 400°C for up to 4 hr. to
remove phthalates and other interfering organic substances.
Alternatively, it can be extracted with methylene chloride in
a Soxhlet apparatus for 48 hr. Store in a capped glass
bottle rather than a plastic container.
7.3.2 COPPER II SULFATE PENTAHYDRATE, CuS04"5H20 -- ACS re-
agent grade.
7.3.3 SODIUM BICARBONATE, NaHC03 — ACS reagent grade.
7.3.4 AMMONIUM CHLORIDE, NH^Cl — ACS reagent grade, used to
convert free chlorine to monochloramine. Although this
is not the traditional dechlorination mechanism, ammoni-
um chloride is categorized as a dechlorinating agent in
this method.
7.4 SOLUTIONS
7.4.1 10% H2S04/METHANOL SOLUTION — Use caution when prepar-
ing sulfuric acid solutions. To prepare a 10% solution,
add 5 mL sulfuric acid dropwise (due to heat evolution)
552.2-8
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7.4.2
to 20-30 ml methanol contained in a 50.0 ml volumetric
flask that has been placed in a cooling bath. Then
dilute to the 50.0 ml mark with methanol.
SATURATED SODIUM BICARBONATE SOLUTION — Add sodium
bicarbonate to a volume of water, mixing periodically
until the solution has reached saturation.
7.5 STANDARDS
7.5.1 1,2,3-TRICHLOROPROPANE, 99+% -- For use as the internal
standard. Prepare an internal standard stock standard solu-
tion of 1,2,3-trichloropropane in MTBE at a concentration of
approximately 1 mg/mL. From this stock standard solution,
prepare a primary dilution standard in MTBE at a concentra-
tion of 25 fig/ml.
7.5'.2 2,3-OIBROMOPROPIONIC ACID, 99+% -- For use as a surrogate
compound. Prepare a surrogate stock standard solution of
2,3-dibromopropionic acid in MTBE at a concentration of
approximately 1 mg/mL. From this stock standard solution,
prepare a primary dilution standard in MTBE at a concentra-
tion of 10 ng/ml.
7.5.3 STOCK STANDARD SOLUTION (SSS)
Prepare separate stock standard solutions for each analyte of
interest at a concentration of 1-5 mg/mL in MTBE. Method
analytes may be obtained as neat materials or ampulized
solutions (> 99% purity) from a number of commercial suppli-
ers. These stock standard solutions shcald be stored at -
10°C and protected from light. They are stable for at least
one month but should be checked frequently for signs of
evaporation.
7.5.3.1. For analytes which are solids in their pure form,
prepare stock standard solutions by accurately
weighing approximately 0.01 to 0.05 grams of pure
material in a 10.0 ml volumetric flask. Dilute to
volume with MTBE. When a compound purity is assayed
to be 96% or greater, the weight can be used without
correction to calculate the concentration of the
stock standard.
7.5.3.2. Stock standard solutions for analytes which are
liquid in their pure form at room temperature can
be accurately prepared in the following manner.
7.5.3.3. Place about 9.8 mL of MTBE into a 10.0 mL volumetric
flask. Allow the flask to stand, unstoppered, for
about 10 minutes to allow solvent film to evaporate
552.2-9
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from the inner walls of the volumetric, and weigh to
the nearest 0.1 mg.
7.5.3.4. Use a 10 fil syringe and immediately add 10.0 /*L of
standard material to the flask by keeping the
syringe needle just above the surface of the MTBE.
Be sure that the standard material falls dropwise
directly into the MTBE without contacting the inner
wall of the volumetric.
7.5.3.5. Reweigh, dilute to volume, stopper, then mix by
inverting the flask several times. Calculate the
concentration in milligrams per milliliter from the
net gain in weight.
7.5.4 PRIMARY DILUTION STANDARD (PDS) — Prepare the primary
dilution standard solution by combining and diluting stock
standard solutions with MTBE (the surrogate stock standard
solution was prepared in Section 7.5.2). This primary
dilution standard solution should be stored at -10°C and
protected from light. It is stable for at least one month
but should be checked before use for signs of evaporation.
As a guideline to the analyst, the primary dilution standard
solution used in the validation of this method is described
below.
Concentration. ug/mL
Monochloroacetic acid 60
Monobromoacetic acid 40
Dalapon 40
Dichloroacetic acid 60
Trichloroacetic acid 20
Bromocnloroacetic acid 40
Dibromoacetic acid 20
Bromodichloroacetic acid 40
Chlorodibromoacetic acid 100
Tribromoacetic acid 200
2,3-Dibromopropionic acid (surr.) 100
This primary dilution standard is used to prepare calibration
standards, which comprise five concentration levels of each
analyte with the lowest standard being at or near the MDL of
each analyte. The concentrations of the other standards
should define a range containing the expected sample
concentrations or the working range of the detector.
NOTE: When purchasing commercially prepared standards, solu-
tions prepared in methanol must not be used because it has
been found that the haloacetic acids are subject to
spontaneous methylation when stored.in this solvent (12).
552.2-10
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Furthermore, tribromoacetic acid has been found to be unsta-
ble in methanol because it undergoes decarboxylation when
stored in this solvent.
7,5.4.1. Include the surrogate analyte, 2,3-dibromopropionic
acid, within the primary dilution standard prepared
in Section 7.5.4. By incorporating the surrogate
into the primary dilution standard, it is diluted
alongside the target analytes in the standard
calibration curve. This is done so that the peaks
for the surrogate and the ester of chlorodibromo-
acetic acid, which elute fairly closely, are
relatively close in size and adequate resolution is
therefore insured. Furthermore, if a sample should
have a very large concentration of chlorodibromo-
acetic acid, it may be impossible to obtain an
accurate measurement of surrogate recovery. If this
happens, reextraction with a higher surrogate
concentration would be an option.
7.5.6 LABORATORY PERFORMANCE CHECK STANDARD (LPC) — A low level
calibration standard can serve as the LPC standard.
8- SAMPLE COLLECTION. PRESERVATION AND STORAGE
8.1 SAMPLE VIAL PREPARATION
8.1.1 Grab samples must be collected in accordance with conven-
tional sampling practices (13) using amber glass containers
with TFE-lined screw-caps and capacities of at least 50 ml.
8.1.2 Prior to shipment to the field, add crystalline or granular
ammonium chloride (NH4C1) to the sample container in an
amount to produce a concentration of 100 mg/L in the sample.
For a typical 50 mL sample, 5 mg of ammonium chloride is
added.
NOTE: Enough ammonium chloride must be added to the sample
to convert the free chlorine residual in the sample matrix to
combined chlorine. Typically, the ammonium chloride
concentration here will accomplish that. If high doses of
chlorine are used, additional ammonium chloride may be re-
quired.
8.2 SAMPLE COLLECTION
8.2.1 Fill sample bottles to just overflowing but take care not to
flush out the ammonium chloride.
8.2.2 When sampling from a water tap, open the tap and allow the
system to flush until the water temperature has stabilized
(usually about 3-5 minutes). Remove the aerator so that no
552.2-11
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air bubbles can be visibly detected and collect samples from
the flowing system.
8.2.3 When sampling from an open body of water, fill a 1-quart
wide-mouth bottle or 1-liter beaker with sample from a
representative area, and carefully fill sample vials from the
container.
8.2.4 After collecting the sample in the bottle containing the
ammonium chloride, seal the bottle and agitate by hand for 1
min.
8.3 SAMPLE STORAGE/HOLDING TIMES
8.3.1 Samples must be iced or refrigerated at 4°C and maintained at
these conditions away from light until extraction. Synthetic
ice (i.e., blue ice) is not recommended. Holding studies
performed to date have suggested that, in samples preserved
with NH/C1, the analytes are stable for up to 14 days. Since
stability may be matrix dependent, the analyst should verify
that the prescribed preservation technique is suitable for
the samples under study.
8.3.2 Extracts (Section 11.2.7) must be stored at 4°C or less away
from light in .glass vials with Teflon-lined caps. Extracts
must be analyzed within 7 days from extraction if stored at
4°C or within 14 days if stored at -10°C or less.
9. QUALITY CONTROL
9.1 Each laboratory that uses this method is required to operate a
formal quality control (QC) program. Minimum quality control
requirements are monitoring the laboratory performance check stan-
dard, initial demonstration of laboratory capability, performance of
the method detection limit study, analysis of laboratory reagent
blanks and laboratory fortified sample matrices, determination of
surrogate compound recoveries in each sample and blank, monitoring
internal standard peak area or height in each sample, blank and CCC,
and analysis of QC samples. Additional QC practices may be added.
9.2 LABORATORY PERFORMANCE CHECK STANDARD (LPC)
At the beginning of an analysis set, prior to any calibration
standard or sample analysis and after an initial solvent analysis, a
laboratory performance check standard must be analyzed. This check
standard insures proper performance of the GC by evaluation of the
instrument parameters of detector sensitivity, peak symmetry, and
peak resolution. It furthermore serves as a check.on the continuity
of the instrument's performance. In regards to sensitivity, it
allows the analyst to ascertain that this parameter has not changed
drastically since the analysis of the MDL study. Inability to
demonstrate acceptable instrument performance indicates the need for
552.2-12
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re-evaluation of the instrument system.
Table 8.
Criteria are listed in
9.2.1 The sensitivity requirement is based on the EDLs published in
this method. If laboratory EDLs differ from those listed in
Table 2, concentrations of the LPC standard may be adjusted
to be compatible with the laboratory EDLs.
9.2.2 If column or chromatographic performance cannot be met, one
or more of the following remedial actions should be taken.
Break off approximately 1 meter of the injector end of the
column and re-install, install a new column, adjust column
flows or modify the oven temperature program.
9.3 INITIAL DEMONSTRATIONS CAPABILITY (IDC)
9.3.1 Calibrate for each analyte of interest as specified in
Section 10. Select a representative fortification
concentration for each of the target analytes.
Concentrations near those in Table 4 are recommended.
Prepare 4-7 replicates laboratory fortified blanks by adding
an appropriate aliquot of the primary dilution standard or
quality control sample to reagent water. (This reagent water
should contain ammonium chloride at the same concentration
as that specified for samples as per Section 8.1.2.) Analyze
the LFBs according to the method beginning in Section 11.
9.3.2 Calculate the mean percent recovery and the standard devia-
tion of the recoveries. For each analyte, the mean recovery
value, expressed as a percentage of the true value, must fall
in the range of 80-120% and the relative standard deviation
should be less than 20%. For those compounds that meet these
criteria, performance is considered acceptable and sample
analysis may begin. For those compounds that fail these
criteria, this procedure must be repeated using 4-7 fresh
samples until satisfactory performance has been demonstrated.
Maintain these data on file to demonstrate initial
capabilities.
9.3.3 Furthermore, before processing any samples, the analyst must
analyze at least one laboratory reagent blank to demonstrate
that all glassware and reagent interferences are under
control.
9.3.4 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. As laboratory personnel gain experience with this
method, the quality of data should improve beyond those re-
quired here.
552.2-13
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9.3.5 The analyst is permitted to modify GC columns, GC conditions,
internal standard or surrogate compounds. Each time such
method modifications are made, the analyst must repeat the
procedures in Section 9.3.1 through Section 9.3.4 and Sect.
9.4.
9.4 METHOD DETECTION LIMIT STUDY (MDL)
9.4.1. Prior to the analysis of any field samples, the method
detection limits must be determined. Initially, estimate the
concentration of an analyte which would yield a peak equal to
5 times the baseline noise and drift. Prepare seven
replicate laboratory fortified blanks at this estimated
concentration with reagent water that contains ammonium
chloride at the same concentration as that specified for
samples as per Section 8.1.2. Analyze the LFB's according to
the method beginning in Section 11.
9.4.2. Calculate the mean recovery and the standard deviation for
each analyte. Multiply the student's t value at 99% confi-
dence and n-1 degrees of freedom (3.143 for seven replicates)
by this standard deviation to yield a statistical estimate of
the detection limit. This calculated value is the MDL.
9.4.3. Since the statistical estimate is based on the preci- sion
of the analysis, an additional estimate of detection can be
determined based upon the noise and drift of the baseline as
well as precision. This estimate is the EDL (Table 2).
9.5 LABORATORY REAGENT BLANKS (LRB) — Each time a set of samples is
extracted or reagents are changed, a LRB must be analyzed. If the
LRB produces an interferant peak within the retention time window
(Section 12.3} of any analyte that would prevent the determination
of that analyte or a peak of concentration greater than the MDL for
that analyte, the analyst must determine the source of contamination
and eliminate the interference before processing samples. Field
samples of an extraction set associated with an LRB that has failed
the specified criteria are considered suspect.
NOTE: Reagent water containing ammonium chloride at the same
concentrations as in the samples (Section 8.1.2) is used to prepare
the LRB.
9.6 LABORATORY FORTIFIED BLANK (LFB) -- Since this method utilizes
procedural calibration standards,, which are fortified reagent water,
there is no difference between the LFB and the continuing
calibration check standard. Consequently, the analysis of an LFB is
not required (Section 10.2).
552.2-14
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9.7 LABORATORY FORTIFIED SAMPLE MATRIX (LFM)
9.7.1 Chlorinated water supplies will usually contain significant
background concentrations of several method analytes, espe-
cially dichloroacetic acid (DCAA) and trichloroacetic acid
(TCAA). The concentrations of these acids may be equal to or
greater than the fortified concentrations. Relatively poor
accuracy and precision may be anticipated when a large
background must be subtracted. For many samples, the concen-
trations may be so high that fortification may lead to a
final extract with instrumental responses exceeding the
linear range of the electron capture detector. If this
occurs, the extract must be diluted. In spite of these
problems, sample sources should be fortified and analyzed as
described below. By fortifying sample matrices and calcu-
lating analyte recoveries, any matrix induced analyte bias is
evaluated.
9.7.2. The laboratory must add known concentrations of analytes to
one sample per extraction set or a minimum of 10% of the
samples, whichever is greater. The concentrations should be
equal to or greater than the background concentrations in the
sample selected for fortification. If the fortification
level is less than the background concentration, recoveries
are not reported. Over time, samples from all routine sample
sources should be fortified.
9.7.3 Calculate the mean percent recovery, R, of the concentration
for each analyte, after correcting the total mean measured
concentration. A, from the fortified sample for the back-
ground concentration, B, measured in the unfortified sample,
i.e.:
R = 100 (A - B) / C,
where C is the fortifying concentration. In order for the
recoveries to be considered acceptable, they must fall
between 70% and 130% for all the target analytes.
9.7.4 If a recovery falls outside of this acceptance range, a
matrix induced bias can be assumed for the respective analyte
and the data for that analyte must be reported to the data
user as suspect due to matrix effects.
9.8 ASSESSING SURROGATE RECOVERY
The surrogate analyte is fortified into the aqueous portion of all
continuing calibration standards, samples and laboratory reagent
blanks. The surrogate is a means of assessing method performance in
every analysis from extraction to final chromatographic performance.
552.2-15
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9.8.1 When surrogate recovery from a sample, blank or CCC is < 70%
or > 130%, check (1) calculations to locate possible errors,
(2) standard solutions for degradation, (3) contamination,
and (4) instrument performance. If those steps do not reveal
the cause of the problem, reanalyze the extract.
9.8,2 If the extract reanalysis meets the surrogate recovery
criterion, report only data for the reanalyzed extract.
9.8.3 If the extract reanalysis fails the 70-130% recovery
criterion, the analyst should check the calibration by
analyzing the most recently acceptable continuing calibration
check standard. If the CCC fails the criteria of Section
10.2.1, recalibration is in order per Section 10.1. If the
CCC is acceptable, it may be necessary to extract another
aliquot of sample. If the sample re-extract also fails the
recovery criterion, report all data for that sample as
suspect.
9.9 ASSESSING THE INTERNAL STANDARD
9.9.1. The analyst must to monitor the IS response (peak area or
peak height) of all injections during each analysis day.
A mean IS response should be determined from the five point
calibration curve. The IS response for any run should not
deviate from this mean IS response by more than 30%. It is
also acceptable if the IS response of a injection is within
15% of the daily continuing calibration standard IS response.
9.9.2 If a deviation greater than this occurs with an individual
extract, optimize instrument performance and inject a second
aliquot of that extract.
9.9.2.1 If the reinjected aliquot produces an acceptable
internal standard response, report results for that
aliquot.
9.9.2.2 If a deviation of greater than 30% is obtained for
the reinjected extract, the analyst should check the
calibration by analyzing the most recently
acceptable CCC. If the CCC fails the criteria of
Section 10.2.1, recalibration is in order per
Section 10.1. If the CCC is acceptable, analysis of
the sample should be repeated beginning with Section
11, provided the sample is still available. Oth-
erwise, report results obtained from the reinjected
extract, but annotate as suspect.
9.10 QUALITY CONTROL SAMPLE (QCS) ~ At least quarterly, analyze a QCS
from an external source. If measured analyte concentrations are not
of acceptable accuracy, check the entire analytical procedure to
locate and correct the problem source.
552.2-16
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9.11 The laboratory may adapt additional QC 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.
10. CALIBRATION AND STANDARDIZATION
10.1 INITIAL CALIBRATION CURVE
10.1.1 Calibration is performed by extracting procedural standards,
i.e.; fortified reagent water, by the procedure set forth in
Section 11. A five-point calibration curve is to be prepared
by diluting the primary dilution standard into MTBE at the
appropriate levels. The desired amount of each MTBE
calibration standard is added to separate 40 ml aliquots of
reagent water to produce a calibration curve ranging from the
detection limit to approximately 50 times the detection
limit. (These MTBE calibration standards should be prepared
so that 20 //L or less of the solution is added the water
aliquots.) Also, the reagent water used for the procedural
standards contains ammonium chloride at the same concentra-
tion as that in the samples as per Section 8.1.2.
10.1.2 Establish GC operating parameters equivalent to the suggested
specifications in Table 1. The GC system must be calibrated
using the internal standard (IS) technique. Other columns or
conditions may be used if equivalent or better performance
can be demonstrated.
10.1.2 Five calibration standards are required. The lowest should
contain the analytes at a concentration near to but greater
than the MDL (Table 2) for each compound. The others should
be evenly distributed throughout the concentration range
expected in the samples.
10.1.3 Inject 2 /iL of each calibration standard extract and tabulate
peak height or area response and concentration for each
analyte and the internal standard.
10.1.4 Generate a calibration curve by plotting the area ratios
(Aa/Ais) against the concentration Ca of the five calibration
standards where
Aa is the peak area of the analyte.
Ajs is the peak area of the internal standard.
C is the concentration of the analyte.
552.2-17
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This curve can be defined as either first or second order.
Also, the working calibration curve must be verified daily by
measurement of one or more calibration standards (Section
10.2). If the response for any analyte falls outside the
predicted response by more than 30%, the calibration check
must be repeated using a freshly prepared calibration stan-
dard. Should the retest fail, a new calibration curve must
be generated.
10.1.5 Alternately, an average relative response factor can be
calculated and used for quantitation. Relative response
factors are calculated for each analyte at the five
concentration levels using the equation below:
RRF
-------
10.2.2 If this criteria cannot be met, the continuing calibration
check standard extract is re-injected in order to determine
if the response deviations observed from the initial analysis
are repeated. If this criteria still cannot be met, a second
CCC should be extracted and analyzed or a CCC that has
already been analyzed and has been found to be acceptable
should be run. If this second CCC fails, then the instrument
is considered out of calibration and needs to be
recalibrated.
11. PROCEDURE
11.1 SAMPLE EXTRACTION
11.1.1 Remove the samples from storage (Sect. 8.3.1) and allow them
.to equilibrate to room temperature.
11.1.2 Place 40 ml of the water sample into a precleaned 60 ml glass
vial with a teflon-lined screw cap using a graduated
cylinder.
11.1.3 Add 20 /j(L of surrogate standard (10.0 jug/ml 2,3-dibromo-
propionic acid in MTBE per Section 7.5.2).
NOTE: When fortifying an aqueous sample with either
surrogate or target analytes contained in MTBE, be sure that
the needle of the syringe is well below the level of the
water. After injection, cap the sample and invert once.
This insures that the standard solution is mixed well with
the water.
11.1.4 Adjust the pH to less than 0.5 by adding at least 2 mL of
concentrated sulfuric acid. Cap, shake and then check the pH
with a pH meter or narrow range pH paper.
11.1.5 Quickly add approximately 2 g of copper II sulfate
pentahydrate and shake until dissolved. This colors the
aqueous phase blue and therefore allows for the analyst to
better distinguish between the aqueous phase and the organic
phase in this micro extraction.
11.1.6 Quickly add 16 g of muffled sodium sulfate and shake for 3 to
5 minutes until almost all is dissolved. Sodium sulfate Is
added to increase the ionic strength of the aqueous phase and
thus further drive the haloacetic acids into the organic
phase. The addition of this salt and the copper II sulfate
should be done quickly so that the heat generated from the
addition of the acid (Section 11.1.4) will help dissolve the
salts.
552.2-19
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11.1.7 Add 4.0 ml MTBE and place on the mechanical shaker for 30
minutes. (If hand-shaken, two minutes is sufficient if
performed vigorously).
11.1.8 Allow the phases to separate for approximately 5 minutes.
11.2 METHYLATION
11.2.1 Using a pasteur pipet, transfer approximately 3 ml of the
upper MTBE layer to a 15 ml graduated conical centrifuge
tube.
11.2.2 Add 1 ml 10% sulfuric acid in methanol to each centrifuge
tube.
11.2.3 Cap the centrifuge tubes and place in the heating block (or
sand bath) at 50°C and maintain for 2 hr. The vials must fit
snugly into the heating block to ensure proper heat transfer.
At this stage, methylation of the method analytes is at-
tained.
11.2.4 Remove the centrifuge tubes from the heating block (or sand
bath) and allow them to cool before removing the caps.
11.2.5 Add 4 ml saturated sodium bicarbonate solution to each
centrifuge tube in 1 ml increments. Exercise caution when
adding the solution because the evolution of C02 in this
neutralization reaction is rather rapid.
11.2.6 Shake each centrifuge tube for 2 minutes. As the neutral-
ization reaction moves to completion, it is important to
continue to exercise caution by venting frequently to release
the evolved C02.
11.2.7 Transfer exactly 1.0 ml of the upper MTBE layer to an auto-
sampler vial. A duplicate vial should be filled using the
excess extract.
11.2.8 Add 10 pi of internal standard to the vial to be analyzed.
(25 pg/wl 1,2,3-trichloropropane in MTBE per Section 7.5.1).
11.2.9 Analyze the samples as soon as possible. The sample extract
may be stored up to 7 days if kept at 4°C or less or up to 14
days if kept at -10°C or less. Keep the extracts away from
light in amber glass vials with Teflon-lined caps.
11.3 GAS CHROMATOGRAPHY
11.3.1 Table 1 summarizes recommended GC operating conditions and
retention times observed using this method. Figure 1 illus-
trates the performance of the recommended primary column with
the method analytes. Figure 2 illustrates the performance of
552.2-20
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the recommended confirmation column with the method analytes.
Concentrations of the analytes of these chromatograms are
those listed in Table 4 for the fortified reagent water
samples. Other GC columns or chromatographic conditions may
be used if the requirements of Section 9 are met.
11.3.2 Calibrate the system (Section 10.1) or verify the existing
calibration by analysis of a CCC daily as described in
Section 10.2.
11.3.3 Inject 2 /zL of the sample extract.
sizes in area or height units.
Record the resulting peak
11.3.4 If the response for the peak exceeds the working range of the
system, dilute the extract, add an appropriate additional
amount of internal standard and reanalyze. The analyst must
not extrapolate beyond the calibration range established.
12. DATA ANALYSIS AND CALCULATIONS
12.1 Identify sample components by comparison of retention times to
retention data from the calibration standard analysis. If the
retention time of an unknown peak corresponds, within limits (Sec-
tion 12.2), to the retention time of a standard compound, then the
identification is considered positive. Calculate analyte concentra-
tions in the samples and reagent blanks from the calibration curves
generated in Section 10.1.
12.2 If an average relative response factor has been calculated (Sect
10.1.5), analyte concentrations in the samples and reagent blanks
are calculated using the following equation:
(Aa)(Cis)
9 (Ajs)(RRF)
12.3 The width of the retention time window used to make identifications
should be based upon measurements of actual retention time varia-
tions 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
chromatogram.
13. METHOD PERFORMANCE
13.1 In a single laboratory, recovery and precision data were obtained at
three concentrations in reagent water (Tables 3 and 4). The MDL and
EDL data are given in Table 2. In addition, recovery and precision
data were obtained at a medium concentration for dechlorinated tap
water (Table 5), high ionic strength reagent water (Table 6) and
high humectant ground water (Table 7).
552.2-21
-------
14. POLLUTION PREVENTION
14.1 This method utilizes a micro-extraction procedure which requires the
use of very small quantities of organic solvents. This feature
reduces the hazards involved with the use of large volumes of poten-
tially harmful organic solvents needed for conventional liquid-
liquid extractions. This method also uses acidic methanol as the
derivatizing reagent.
14.2 For information about pollution prevention that may be applicable to
laboratory operations consult "Less is Better: Laboratory Chemical
Management for Waste Reduction" available from the American Chemical
Society's Department of Government Relations and Science Policy,
1155 16th Street N.W., Washington, D.C. 20036.
15. WASTE MANAGEMENT
15.1 Due to the nature of this method there is little need for waste
management. No large volumes of solvents or hazardous chemicals are
used. The matrices of concern are finished drinking water or source
water. However, the Agency requires that laboratory waste manage-
ment practices be conducted consistent with all applicable rules and
regulations, and that laboratories protect the air, water, and land
by minimizing and controlling all releases from fume hoods and bench
operations. Also compliance is required with any sewage discharge
permits and regulations, particularly the hazardous waste identifi-
cation rules and land disposal restrictions. For further informa-
tion on waste management, consult "The Waste Management Manual for
Laboratory Personnel" also available from the American Chemical
Society at the address in Sect. 14.2.
16. REFERENCES
1. Quimby, B.D., Delaney, M.F., Uden. P.C. and Barnes, R.M. Anal.
Chem. 52, 1980, pp. 259-263.
2. Uden, P.C. and Miller, J.W., J. Am. Water Works Assoc. 15, 1983, pp.
524-527.
3. Hodgeson, J.W. and Cohen, A.L. and Collins, J.D., "Analytical
Methods for Measuring Organic Chlorination Byproducts", Proceedings
Watejr Quality Technology Conference (WQTC-16), St. Louis, MO, Nov.
13-17, 1988, American Water Works Association, Denver, CO, pp. 981-
1001.
4. Fair. P.S., Barth, R.C., "Comparison of the Microextraction
Procedure and Method 552 for the Analysis of HAAs and
Chlorophenols", Journal AWWA, November, 1992, pp. 94-98.
552.2-22
-------
5. Chinn, R. and Krasner, S. " A Simplified Technique for the Measure-
ment of Halogenated Organic Acids in Drinking Water by Electron
Capture Gas Chromatography". Presented at the 28th Pacific Confer-
ence on Chemistry and Spectroscopy, Pasadena, CA, October, 1989
6. Hodgeson, J. W., Collins, J. D., and Becker, D. A., "Advanced Tech-
niques for the Measurement of Acidic Herbicides and Disinfection
Byproducts in Aqueous Samples," Proceedings of the 14th Annual EPA
Conference on Analysis of Pollutants in the Environment, Norfolk,
VA., May 8-9, 1991. Office of Water Publication No. 821-R-92-001,
U.S. Environmental Protection Agency, Washington, DC, pp 165-194.
7. Shorney, Holly L. and Randtke, Stephen J., "Improved Methods for
Haloacetic Acid Analysis", Proceedings Water Quality Technology
Conference, San Francisco, CA, November 6-10, 1994, American Water
Works Association, pp 453-475.
8. Peters, Rund J.B., Erkelens, Corrie, De Leer, Ed W.B. and De Galan,
Leo, "The Analysis of Halogenated Acetic Acids in Dutch Drinking
Water", Wat. Res., Vol.25, No.4, 1991, Great Britain, pp 473-477.
9. "Carcinogens-Working with Carcinogens", Publication No. 77-206,
Department of Health, Education, and Welfare, Public Health Service,
Center for Disease Control, National Institute of Occupational
Safety and Health, Atlanta, Georgia, August 1977.
10. "OSHA Safety and Health Standards, General Industry", (29CFR1910),
OSHA 2206, Occupational Safety and Health Administration, Washing-
ton, D.C. Revised January 1976.
11. "Safety In Academic Chemistry Laboratories", 3rd Edition, American
Chemical Society Publication, Committee on Chemical Safety, Washing-
ton, D.C., 1979.
12. Xie, Yuefeng, Reckhow, David A., and Rajan, R.V., "Spontaneous
Methylation of Haloacetic Acids in Methanolic Stock Solutions",
Environ. Sci. Technol., Vol.27, No.6, 1993, pp!232-1234.
13. ASTM Annual Book of Standards, Part 31, D3370, "Standard Practice
for Sampling Water", American Society for Testing and Materials,
Philadelphia, PA, p. 76, 1980.
14. 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.
15. Glaser, J. A., Foerst, D. L., McKee, G. 0., Quave, S. A. and Budde,
W. L., Environ. Sci. Technol. 15, 1981, pp. 1426-1435.
552.2-23
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TABLE 1. RETENTION DATA AND CHROMATOGRAPHIC CONDITIONS
Analyte
Monochloroacetic Acid (MCAA)
Monobromoacetic Acid (MBAA)
Dichloroacetic Acid (OCAA)
Dalapon
Trichloroacetic Acid (TCAA)
Bromochloroacetic Acid (BCAA)
1,2,3-Trichloropropane (I.S.)
Dibromo acetic Acid (DBAA)
Bromodichloroacetic acid (BOCAA)
Chlorodibromoacetic acid (CDBAA)
2,3-Dibromopropionic acid (SURR)
Tribromoacetic Acid (TBAA)
Retention Time.
Column A
13.03
17.15
17.80
19.08
22.67
23.15
23.70
31.38
32.18
41.57
41.77
49.22
min.
Column B
13.70
17.33
17.88
17.73
20,73
22.87
22.35
30.27
28.55
38.78
39.72
47.08
Column A: DB-5.625, 30 m x 0.25 mm i.d., 0.25 tun film thickness,
Injector Temp. = 200°C, Detector Temp. = 260°C, Helium
Linear Velocity - 24 cm/sec at 35°C, Splitless injection
with 30 s delay
Program: Hold at 35°C for 10 min, ramp to 75*C at 5C"/roin. and hold
15 min., ramp to 100"C at 5C°/min. and hold 5 min, ramp to
135°C at 5C°/min. and hold 2 min.
Column B: DB-1701, 30 m xo0.25 mm i.d., 0.25 /zm film thickness, Injec-
tor Temp. « 200°C, Detector Temp. * 260°C, Linear Helium
Velocity = 25 cm/sec at 35"C, splitless injection with 30 s
delay.
Program: Hold at 35*C for 10 min, ramp to 75'C at 5C°/min. and hold
15 min., ramp to 100°C at 5t"/min. and hold 5 min, ramp to
135"C at 5C°/nrin. and hold 0 min.
552.2-26
-------
TABLE 2. ANALYTE ACCURACY AND PRECISION DATA
AND METHOD DETECTION LIMITS0
LEVEL 1 IN REAGENT WATER
Analyte
MCAA
MBAA
DCAA
Dalapon
TCAA
BCAA
DBAA
BDCAA
CDBAA
TBAA
Fortified
Cone.
M9/L
0.600
0.400
0.600
0.400
0.200
0.400
0.200
0.400
1.00
2.00
Mean
Meas.
Cone.
W/L
0.516
0.527
0.494
0.455
0.219
0.498
0.238
0.357
1.19
1.91
Std.
Dev.
W/L
0.087
0.065
0.077
0.038
0.025
0.080
0.021
0.029
0.149
0.261
Rel.
Std.
Dev., %
17
12
16
8.4
11
16
8.8
8.1
12
14
Method
Detection
Limit"
W/L
0.273
0.204
0.242
0.119
0.079
0.251
0.066
0.091
0.468
0.820
Estimated
Detection
Limit6
W/L
0.60
0.20
0.24
0.40
0.20
0.25
0.20
0.40
0.75
1.5
a Produced by analysis of seven aliquots of fortified reagent water.
b The MDL is a statistical estimate of the detection limit. To determine the MDL for
each analyte, the standard deviation of the mean concentration of the seven replicates
is calculated. This standard deviation is then multiplied by the student's t-value at
99% confidence and n-1 degrees of freedom (3.143 for seven replicates). The result is
the MDL.
c The EDL is defined as either the MDL or a level of a compound in a sample yielding a
peak in the final extract with a signal to noise (S/N) ratio of approximately 5,
whichever is greater.
552.2-27
-------
TABLE 3. ANALYTE ACCURACY AND PRECISION DATA"
LEVEL 2 IN REAGENT WATER
Fortified
Cone.
Analyte ng/i
Monochloroacetic Acid
Monobromoacetic Acid
Dichloroacetic Acid
Dalapon
Trichloroacetic Acid
Bromochloroacetic Acid
Dibromoacetic Acid
Bromodichloroacetic Acid
Chlorodibromoacetic Acid
Tribromoacetic Acid
1.50
1.00
1.50
1.00
0.500
1.00
0.500
1.00
2.50
5.00
Mean
Meas.
Cone.
w/L
1.42
1.02
1.27
0.935
0.465
0.869
0.477
1.07
2.62
5.19
Std.
Dev.
W/L
0.103
0.051
0.122
0.087
0.048
0.049
0.044
0.098
0.150
0.587
Rel.
Std.
Dev., %
7.3
5.0
9.6
9.3
10
5.6
9.2
9.2
5.7
11
Mean
Recovery
%
94.7
102
84.7
93.5
93.0
86.9
95.4
107
105
104
8 Produced by the analysis of seven aliquots of fortified reagent water.
552.2-28
-------
TABLE 4. ANALYTE ACCURACY AND PRECISION DATA9
LEVEL 4 IN REAGENT WATER
Fortified
Cone.
Analyte /jg/L
Monochloroacetic Acid
Monobromoacetic Acid
Dichloroacetic Acid
Dalapon
THchloroacetic Acid
Bromochloroacetic Acid
Dibromoacetic Acid
Bromodichloroacetic Acid
Chlorodibromoacetic Acid
Tribromoacetic Acid
6.00
4.00
6.00
4.00
2.00
4.00
2.00
4.00
10.0
20.0
Mean
Meas.
Cone.
W/L
5.24
4.36
6.89
3.87
1.74
4.33
1.87
3.93
11.4
24.0
Std.
Dev.
M9/L
0.664
0.475
0.782
0.147
0.144
0.402
0.113
0.377
0.866
1.82
Rel.
Std.
Dev., %
13
11
11
3.8
8.3
9.3
6.0
9.6
7.6
7.6
Mean
Recovery
%
87.3
109
115
96.8
87.0
108
93.5
98.2
114
120
8 Produced by the analysis of seven aliquots of fortified reagent water.
552.2-29
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TABLE 5. AHALYTE ACCURACY AND PRECISION DATA*'"
LEVEL 3 IN OECHLORINATED TAP WATER6
Background
Cone.
Analyte /ig/L
Monochloroacetic Acid
Monobromoacetic Acid
Dichloroacetic Acid
Dal apon
Trichloroacetic Acid
Bromochloroacetic Acid
Dibromoacetic Acid
Bromodichloroacetic Acid
Chlorodibromoacetic Acid
Tribromoacetic Acid
<0.6
0.420
0.625
<0.4
0.300
1.23
1.27
0.588
1.23
<2.0
Forti-
fied
Cone.
W/L
3.00
2.00
3.00
2.00
1.00
2.00
1.00
2.00
5.00
10.0
Mean
Meas.
Cone.
/ig/L
2.53
2.20
3.77
1.96
1.12
2.91
2.35
2.52
6.36
11.8
Std.
Dev.
M/L
0.090
0.034
0.096
0.157
0.167
0.062
0.110
0.388
0.502
1.65
Rel.
Std.
Dev.
%
3.6
1.5
2.5
8.0
15
2.1
4.7
15
7.9
14
Mean
Rec.
%
84.3
89.0
105
98.0
82.0
84.0
108
96.6
103
118
3 Produced by analysis of seven aliquots of fortified dechlorinated tap water.
b Background level subtracted.
c Chlorinated surface water from a local utility to which ammonium chloride was added
as the dechlorinating agent.
552.2-30
-------
TABLE 6. ANALYTE ACCURACY AND PRECISION DATA*'"
LEVEL 3 IN HIGH IONIC STRENGTH WATERC
Background
Cone.
Analyte /tg/L
Monochloroacetic Acid
Monobromoacetic Acid
Dlchloroacetic Acid
Dalapon
Trichloroacetic Acid
Bromochloroacetic Acid
Dibromoacetic Acid
Bromodichloroacetic Acid
Chlorodibromoacetic Acid
Tribromoacetic Acid
0.761
1.47
1.50
0.675
1.01
2.06
4.36
1.07
2.48
4.63
Forti-
fied
Cone.
M9/L
3.00
2,00
3.00
2.00
1.00
2.00
1.00
2.00
5.00
10.0
Mean
Meas.
Cone.
W/L
3.32
3.19
4.44
2.39
1.75
3.71
5.48
3.37
7.94
17.2
Std.
Dev.
W/L
0.429
0.099
0:264
0.259
0.110
0.269
0.255
0.308
1.00
1.55
Rel.
Std. Mean
Dev. Rec
% %
13
3.1
5.9
11
6.3
7.3
4.7
9.1
13
9.0
85.3
86.0
98.0
85.8
74.0
82.5
112
115
109
126
* Produced by analysis of seven aliquots of fortified high ionic strength water.
b Background level subtracted.
0 Chlorinated ground water from a water source displaying a hardness of 460 mg/L as
CaC03
552.2-31
-------
TABLE 7. ANALYTE ACCURACY AND PRECISION DATA3
LEVEL 3 IN HIGH HUHIC CONTENT GROUND WATER"
Background
Cone.
Analyte M9/L
Monochloroacetic Acid
Monobromoacetic Acid
Dichloroacetic Acid
Oalapon
Trichloroacetic Acid
Bromochloroacetic Acid
Dibromoacetic Acid
Bromodichloroacetic Acid
Chlorodibromoacetic Acid
Tribromoacetic Acid
<0.6
<0.4
<0.6
<0.4
<0.2
<0.4
<0.2
<0.4
-------
TABLE 8. LABORATORY PERFORMANCE CHECK SOLUTION
PARAMETER
INSTRUMENT
SENSITIVITY
CHROMATOGRAPHIC
PERFORMANCE
COLUMN
PERFORMANCE
ANALYTE
MCAA
BCAA
CDBAA
SURROGATE. (2,3-DBPA)
CONC., tig/ml
IN MTBE
0.006
0.004
0.010
0.010
ACCEPTANCE
CRITERIA
DETECTION OF
ANALYTE;
S/Na > 3
PGFb BETWEEN
0.80 AND 1.15
RESOLUTION0
> 0.50
S/N, a ratio of peak signal to baseline noise.
peak signal - measured as height of peak.
baseline noise - measured as maximum deviation in baseline (in units of height)
over a width equal to the width of the base of the peak.
PGF = Peak Gaussian Factor
1.83 x W
1/2
PGF =
where W1/2 = the peak width at half height (in sees).
W1/10 = the peak width at one-tenth height (in sees)
This is a measure of the symmetry of the peak.
c Resolution between two peaks is defined by the equation:
t
ave
where t = the difference in elution times between the two peaks.
Wave = the average peak width of the two peaks (measurements taken at
baseline).
This a measure of the degree of separation of two peaks under specific chromatographic
conditions.
552.2-33
*U.S. GOVERNMENT PRINTING OFFICE: 1996 - 750-001/< 1001
-------
-------
U.S. EPA Headquarters Library
Mail code 3201
1200 Pennsylvania Avenue NW
Washington DC 20460
(nformatfon Resources Center
US EPA (3404)
401 M Street, SW
Washin@tont DC 20460
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