ASTM D5317-20

Standard Test Method for Determination of Chlorinated Organic Acid Compounds in Water by Gas Chromatography with an Electron Capture Detector

SIGNIFICANCE AND USE
5.1 Chlorinated phenoxyacid herbicides, and other organic acids are used extensively for weed control. Esters and salts of 2,4-D and silvex have been used as aquatic herbicides in lakes, streams, and irrigation canals. Phenoxy acid herbicides can be toxic even at low concentrations. For example, the 96 h, TLm for silvex is 2.4 mg/L for bluegills (1).8 These reasons make apparent the need for a standard test method for such compounds in water.
SCOPE
1.1 This test method covers a gas chromatographic procedure for the quantitative determination of selected chlorinated acids and other acidic herbicides in water. Similar chemicals may also be determined by this test method, but it is the user’s responsibility to verify the applicability of this test method to any compounds not listed in this scope. The acid form of the following compounds were interlaboratory tested using this test method, and the results were found acceptable:2    
Analyte  
Chemical Abstract Services
Registry Number  
Bentazon  
25057-89-0  
2,4-D  
94-75-7  
2,4-DB  
94-82-6  
DCPA acid metabolites 2  
Dicamba  
1918-00-9  
3,5-Dichlorobenzoic acid  
51-36-5  
Dichlorprop  
120-36-5  
5-Hydroxydicamba  
7600-50-2  
Pentachlorophenol (PCP)  
87-86-5  
Picloram  
1918-02-1  
2,4,5-T  
93-76-5  
2,4,5-TP (Silvex)  
93-72-1  
1.2 This test method may be applicable to the determination of salts and esters of analyte compounds. The form of each acid is not distinguished by this test method. Results are calculated and reported for each listed analyte as the total free acid.  
1.3 This test method has been validated in an interlaboratory test for reagent water and finished tap water. The analyst should recognize that precision and bias reported in Section 18 may not be applicable to other waters.  
1.4 This test method is restricted to use by or under the supervision of analysts experienced in the use of gas chromatography (GC) and in the interpretation of gas chromatograms. Each analyst must demonstrate the ability to generate acceptable results with this test method using the procedure described in 19.3. It is the user’s responsibility to ensure the validity of this test method for waters of untested matrices.  
1.5 Analytes that are not separated chromatographically, that is, which have very similar retention times, cannot be individually identified and measured in the same calibration mixture or water sample unless an alternate technique for identification and quantitation exists (16.6, 16.7, and 16.8).  
1.6 When this test method is used to analyze unfamiliar samples for any or all of the analytes given in 1.1, analyte identifications must be confirmed by at least one additional qualitative technique.  
1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see Sections 6, 8, 9, and 10.  
1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 14-Aug-2020
• ICS: 71.080.40 - Organic acids
• Technical Committee: D19 - Water
• Drafting Committee: D19.06 - Methods for Analysis for Organic Substances in Water

Relations

• Refers: ASTM D1129-13(2020)e2 - Standard Terminology Relating to Water
• Effective Date: 01-May-2020
• Refers: ASTM D2777-12 - Standard Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water
• Effective Date: 15-Jun-2012
• Refers: ASTM D3856-11 - Standard Guide for Management Systems in Laboratories Engaged in Analysis of Water
• Effective Date: 15-Nov-2011
• Refers: ASTM D3370-10 - Standard Practices for Sampling Water from Closed Conduits
• Effective Date: 01-Dec-2010
• Refers: ASTM D1129-10 - Standard Terminology Relating to Water
• Effective Date: 01-Mar-2010
• Refers: ASTM D3370-08 - Standard Practices for Sampling Water from Closed Conduits
• Effective Date: 01-Oct-2008
• Refers: ASTM D2777-08 - Standard Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water
• Effective Date: 15-Jan-2008
• Refers: ASTM D3370-07 - Standard Practices for Sampling Water from Closed Conduits
• Effective Date: 01-Dec-2007
• Refers: ASTM D1129-06ae1 - Standard Terminology Relating to Water
• Effective Date: 01-Sep-2006
• Refers: ASTM D1129-06a - Standard Terminology Relating to Water
• Effective Date: 01-Sep-2006
• Refers: ASTM D2777-06 - Standard Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water
• Effective Date: 15-Aug-2006
• Refers: ASTM D1193-06 - Standard Specification for Reagent Water
• Effective Date: 01-Mar-2006
• Refers: ASTM D3856-95(2006) - Standard Guide for Good Laboratory Practices in Laboratories Engaged in Sampling and Analysis of Water
• Effective Date: 15-Feb-2006
• Refers: ASTM D1129-06 - Standard Terminology Relating to Water
• Effective Date: 15-Feb-2006
• Refers: ASTM D1129-04 - Standard Terminology Relating to Water
• Effective Date: 01-Mar-2004

Overview

ASTM D5317-20 establishes the standard test method for the determination of selected chlorinated organic acid compounds in water using gas chromatography (GC) with an electron capture detector (ECD). This method is essential for identifying and quantifying chlorinated phenoxy acid herbicides and related organic acids, which are commonly used in agricultural and aquatic weed control applications. Many of these compounds, including 2,4-D and silvex, can be toxic even at low concentrations, making their accurate detection in water critically important for environmental monitoring and public health.

Key Topics

• Chlorinated Organic Acid Analytes:

  • The method targets specific herbicides and their derivatives, such as Bentazon, 2,4-D, 2,4-DB, DCPA acid metabolites, Dicamba, 3,5-Dichlorobenzoic acid, Dichlorprop, 5-Hydroxydicamba, Pentachlorophenol (PCP), Picloram, 2,4,5-T, and 2,4,5-TP (Silvex).
  • Salts and esters of these compounds may also be quantified but are reported as total free acids.

• Gas Chromatography with ECD:

  • Samples are prepared by adjusting pH, extracting with appropriate solvents, and converting acids to esters.
  • The ECD provides sensitive detection of chlorinated compounds, essential for trace analysis in water.

• Interference Management:

  • Comprehensive procedures are outlined to minimize contamination from reagents, glassware, and plastics.
  • Specific recommendations are provided for cleaning glassware, choosing reagents, and managing matrix interferences.

• Quality Assurance:

  • The method includes procedures for calibration using internal or external standards and ongoing quality control through surrogate standards.
  • Applicability and precision have been validated for reagent and finished tap waters, emphasizing the need for user verification on other matrices.

• Safety Considerations:

  • Detailed safety protocols highlight the handling of hazardous chemicals, such as diazomethane and organic solvents, in compliance with OSHA standards.

Applications

ASTM D5317-20 delivers value in multiple practical contexts:

• Environmental Monitoring:

  • Used by environmental laboratories and regulatory bodies to assess contamination of surface water and drinking water by chlorinated herbicides.
  • Supports routine water quality assessments and compliance with environmental regulations.

• Public Health Protection:

  • Enables early detection of potentially toxic chlorinated organic acids in water sources, contributing to the safeguarding of aquatic life and human health.

• Agricultural and Aquatic Weed Management:

  • Assists in tracking residual herbicides following their use in crop fields, lakes, streams, and irrigation canals.

• Research and Regulatory Compliance:

  • Suited for research studies monitoring the fate of herbicides and for organizations required to demonstrate compliance with local, national, or international water quality standards.

Related Standards

• ASTM D1129 - Terminology Relating to Water
• ASTM D1193 - Specification for Reagent Water
• ASTM D2777 - Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water
• ASTM D3370 - Practices for Sampling Water from Flowing Process Streams
• ASTM D3856 - Guide for Management Systems in Laboratories Engaged in Analysis of Water
• EPA Method 515.1 - Methods for the Determination of Organic Compounds in Drinking Water
• OSHA 29 CFR 1910 - OSHA Safety and Health Standards, General Industry

These related standards offer guidance on terminology, reagent quality, calibration, water sampling, laboratory practices, and safety that support effective implementation of ASTM D5317-20.

Keywords: ASTM D5317-20, chlorinated organic acid compounds, gas chromatography, electron capture detector, herbicide in water, water analysis, environmental monitoring, phenoxy acid herbicides, quality control, water standards.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D5317 − 20
Standard Test Method for
Determination of Chlorinated Organic Acid Compounds in
Water by Gas Chromatography with an Electron Capture
Detector
This standard is issued under the fixed designation D5317; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Each analyst must demonstrate the ability to generate accept-
ableresultswiththistestmethodusingtheproceduredescribed
1.1 This test method covers a gas chromatographic proce-
in 19.3. It is the user’s responsibility to ensure the validity of
dure for the quantitative determination of selected chlorinated
this test method for waters of untested matrices.
acids and other acidic herbicides in water. Similar chemicals
may also be determined by this test method, but it is the user’s 1.5 Analytes that are not separated chromatographically,
responsibility to verify the applicability of this test method to that is, which have very similar retention times, cannot be
any compounds not listed in this scope. The acid form of the individually identified and measured in the same calibration
following compounds were interlaboratory tested using this mixture or water sample unless an alternate technique for
test method, and the results were found acceptable: identification and quantitation exists (16.6, 16.7, and 16.8).
Chemical Abstract Services
1.6 When this test method is used to analyze unfamiliar
Analyte
Registry Number
samples for any or all of the analytes given in 1.1, analyte
identifications must be confirmed by at least one additional
Bentazon 25057-89-0
2,4-D 94-75-7
qualitative technique.
2,4-DB 94-82-6
DCPA acid metabolites 1.7 The values stated in SI units are to be regarded as
Dicamba 1918-00-9
standard. No other units of measurement are included in this
3,5-Dichlorobenzoic acid 51-36-5
standard.
Dichlorprop 120-36-5
5-Hydroxydicamba 7600-50-2
1.8 This standard does not purport to address all of the
Pentachlorophenol (PCP) 87-86-5
safety concerns, if any, associated with its use. It is the
Picloram 1918-02-1
2,4,5-T 93-76-5
responsibility of the user of this standard to establish appro-
2,4,5-TP (Silvex) 93-72-1
priate safety, health, and environmental practices and deter-
1.2 This test method may be applicable to the determination
mine the applicability of regulatory limitations prior to use.
ofsaltsandestersofanalytecompounds.Theformofeachacid
For specific warning statements, see Sections 6, 8, 9, and 10.
is not distinguished by this test method. Results are calculated
1.9 This international standard was developed in accor-
and reported for each listed analyte as the total free acid.
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
1.3 Thistestmethodhasbeenvalidatedinaninterlaboratory
Development of International Standards, Guides and Recom-
testforreagentwaterandfinishedtapwater.Theanalystshould
mendations issued by the World Trade Organization Technical
recognize that precision and bias reported in Section 18 may
Barriers to Trade (TBT) Committee.
not be applicable to other waters.
1.4 This test method is restricted to use by or under the
2. Referenced Documents
supervision of analysts experienced in the use of gas chroma-
2.1 ASTM Standards:
tography (GC) and in the interpretation of gas chromatograms.
D1129 Terminology Relating to Water
D1193 Specification for Reagent Water
D2777 Practice for Determination of Precision and Bias of
This test method is under the jurisdiction of ASTM Committee D19 on Water
Applicable Test Methods of Committee D19 on Water
andisthedirectresponsibilityofSubcommitteeD19.06onMethodsforAnalysisfor
Organic Substances in Water.
Current edition approved Aug. 15, 2020. Published August 2020. Originally
approved in 1992. Last previous edition approved in 2017 as D5317 – 98 (2017). For referenced ASTM standards, visit the ASTM website, www.astm.org, or
DOI: 10.1520/D5317-20. contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
DCPA monoacid and diacid metabolites are included in the scope of this test Standards volume information, refer to the standard’s Document Summary page on
method; DCPA diacid metabolite is used for validation studies. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5317 − 20
D3370 Practices for Sampling Water from Flowing Process 4.2 This test method provides a magnesium silicate
Streams cleanupproceduretoaidintheeliminationofinterferencesthat
D3856 Guide for Management Systems in Laboratories may be present.
Engaged in Analysis of Water
5. Significance and Use
D4210 Practice for Intralaboratory Quality Control Proce-
5.1 Chlorinated phenoxyacid herbicides, and other organic
dures and a Discussion on Reporting Low-Level Data
acids are used extensively for weed control. Esters and salts of
(Withdrawn 2002)
2,4-D and silvex have been used as aquatic herbicides in lakes,
D5789 Practice for Writing Quality Control Specifications
streams, and irrigation canals. Phenoxy acid herbicides can be
for Standard Test Methods for Organic Constituents
toxic even at low concentrations. For example, the 96 h, TL
(Withdrawn 2002)
m
for silvex is 2.4 mg/L for bluegills (1). These reasons make
2.2 EPA Standard:
apparent the need for a standard test method for such com-
Method 515.1 Revision 4.0, Methods for the Determination
pounds in water.
of Organic Compounds in Drinking Water
2.3 OSHA Standard:
6. Interferences
29 CFR 1910 OSHA Safety and Health Standards, General
6.1 Method interferences may be caused by contaminants in
Industry
solvents, reagents, glassware and other sample processing
3. Terminology apparatus that lead to discrete artifacts or elevated baselines in
gas chromatograms. All reagents and apparatus must be rou-
3.1 Definitions:
tinely demonstrated to be free from interferences under the
3.1.1 For definitions of terms used in this standard, refer to
conditions of the analysis by running laboratory reagent blanks
Terminology D1129.
as described in 19.2.
3.2 Definitions of Terms Specific to This Standard:
6.1.1 Glassware must be scrupulously cleaned (2). Clean all
3.2.1 internal standard, n—a pure analyte(s) added to a
glassware as soon as possible after use by thoroughly rinsing
solution in known amount(s) and used to measure the relative
with the last solvent used in it. Follow by washing with hot
responses of other method analytes and surrogates that are
water and detergent and thoroughly rinsing with dilute acid,
components of the same solution.
tap, and reagent water. Drain dry, and heat in an oven or muffle
3.2.1.1 Discussion—The internal standard must be an ana-
furnace at 400°C for 1 h. Do not heat volumetric ware.
lyte that is not a sample component.
Thorough rinsing with acetone may be substituted for the
3.2.2 surrogate analyte, n—a pure analyte(s), which is heating. After drying and cooling, seal and store glassware in
extremely unlikely to be found in any sample, and which is a clean environment to prevent any accumulation of dust or
other contaminants. Store inverted or capped with aluminum
added to a sample aliquot in known amount(s) before extrac-
tionandismeasuredwiththesameproceduresusedtomeasure foil. Thermally stable materials such as PCBs may not be
eliminated by this treatment.
other sample components.
3.2.2.1 Discussion—Thepurposeofasurrogateanalyteisto 6.1.2 The use of high purity reagents and solvents helps to
monitor method performance with each sample. minimize interference problems. Purification of solvents by
distillation in all-glass systems may be required. (Warning—
4. Summary of Test Method
When a solvent is purified, stabilizers added by the manufac-
turer are removed, thus potentially making the solvent hazard-
4.1 The compounds listed in 1.1, in water samples, are
ous. Also, when a solvent is purified, preservatives added by
converted into sodium salts by adjusting the pH to 12 with
the manufacturer are removed, thus potentially reducing the
sodium hydroxide solution (240 g/L) and shaking for 1 h.
shelf-life.)
Extraneous neutral material is removed by extraction with
methylene chloride. The sample is acidified, the acids are
6.2 The acid forms of the analytes are strong organic acids
extracted with ethyl ether and converted to methyl esters using
that react readily with alkaline substances and can be lost
diazomethane.After the excess reagent is removed, the methyl
during sample preparation. Glassware and glass wool must be
estersaredeterminedbycapillarycolumnGCusinganelectron
acid-rinsed with hydrochloric acid (1 + 9) and the sodium
capture (EC) detector. Other detection systems, such as micro-
sulfatemustbeacidifiedwithsulfuricacidpriortousetoavoid
coulometric and electrolytic conductivity, are not as sensitive
analyte loses due to adsorption.
as EC for measurement of chlorinated acid esters but are more
6.3 Organic acids and phenols, especially chlorinated
specific and less subject to interferences. A mass spectrometer
compounds, cause the most direct interference with the deter-
may also be used as a detector.
mination.Alkaline hydrolysis and subsequent extraction of the
basic sample removes many chlorinated hydrocarbons and
The last approved version of this historical standard is referenced on
phthalateestersthatmightotherwiseinterferewiththeelectron
www.astm.org.
capture analysis.
AvailablefromUnitedStatesEnvironmentalProtectionAgency(EPA),William
Jefferson Clinton Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460,
http://www.epa.gov. Florisil, a trademark of, and available from, Floridin Co., 2 Gateway Center,
Available from U.S. Government Printing Office, Superintendent of Pittsburgh, PA15222, or its equivalent, has been found satisfactory for this purpose.
Documents, 732 N. Capitol St., NW, Washington, DC 20401-0001, http:// The boldface numbers in parentheses refer to the list of references at the end of
www.access.gpo.gov. this test method.
D5317 − 20
6.4 Interferences by phthalate esters can pose a major preparation. If this is not the case, chromatographic compara-
problem in pesticide analysis when using the ECD. These bility of standards to sample may be affected.
compounds generally appear in the chromatogram as large
7. Apparatus and Equipment
peaks. Common flexible plastics contain varying amounts of
phthalates, which are easily extracted or leached during labo-
7.1 Sample Bottle—Borosilicate amber, 1-L volume with
ratory operations. Cross contamination of clean glassware
graduations, fitted with screw caps lined with polytetrafluoro-
routinely occurs when plastics are handled during extraction
ethylene (PTFE). Protect samples from light. The container
steps, especially when solvent-wetted surfaces are handled.
must be washed and dried as described in 6.1.1 before use to
Interferences from phthalates can best be minimized by avoid-
minimize contamination. Cap liners are cut to fit from sheets
ingtheuseofplasticsinthelaboratory.Exhaustivepurification
and extracted with methanol overnight prior to use.
of reagents and glassware may be required to eliminate
7.2 Glassware.
background phthalate contamination (3).
7.2.1 Separatory Funnel, 2000-mL, with PTFE stopcocks,
6.5 Interfering contamination may occur when a sample
ground glass or PTFE stoppers.
containing low concentrations of analytes is analyzed imme-
7.2.2 TumblerBottle,1.7-LwithPTFE-linedscrewcap.Cap
diately following a sample containing relatively high concen-
liners are cut to fit from sheets and extracted with methanol
trations of analytes. Between-sample rinsing of the sample
overnight prior to use.
syringe and associated equipment with methyl-t-butyl-ether
7.2.3 Concentrator Tube, Kuderna-Danish (K-D), 10 or
(MTBE) can minimize sample cross contamination. After
25-mL, graduated. Calibration must be checked at the volumes
analysis of a sample containing high concentrations of
employed in the procedure. Ground-glass stoppers are used to
analytes, one or more injections of MTBE should be made to
prevent evaporation of extracts.
ensure that accurate values are obtained for the next sample.
7.2.4 Evaporative Flask, K-D, 500-mL. Attach to concen-
trator tube with springs.
6.6 Matrix interferences may be caused by contaminants
7.2.5 Snyder Column, K-D, three ball macro.
that are coextracted from the sample. Also, note that all
7.2.6 Snyder Column, K-D, two ball micro.
analytes listed in Table 1 are not resolved from each other on
7.2.7 Flask, round bottom, 500-mLwith 24/40 ground glass
any one column, that is, one analyte of interest may be an
joint.
interferent for another analyte of interest. The extent of matrix
7.2.8 Vials, glass, 5 to 10-mL capacity with PTFE-lined
interferences will vary considerably from source to source,
screw cap.
depending upon the water sampled. The procedures in Section
16 can be used to overcome many of these interferences.
7.3 Boiling Stone, PTFE.
Positive identifications should be confirmed. See 16.6, 16.7,
7.4 Water Bath, heated, capable of temperature control
and 16.8.
(62°C). The bath should be used in a hood.
6.7 It is important that samples and working standards be
7.5 Diazomethane Generator—Assemble from two 20- by
contained in the same solvent. The solvent for working
155-mm test tubes, two neoprene rubber stoppers, and a source
standards must be the same as the final solvent used in sample
of nitrogen as shown in Fig. 1.
7.6 Glass Wool, acid washed and heated at 450°C.
TABLE 1 Retention Times and Estimated Method Detection
Limits for Method Analytes
A
Retention Time (min)
B
Analyte CAS No. EDL
Primary Confirmation
3,5-Dichlorobenzoic Acid 51-36-5 18.6 17.7 0.061
DCAA (surrogate) 19719-28-9 22.0 14.9 .
Dicamba 1918-00-9 22.1 22.6 0.081
Dichlorprop 120-36-5 25.0 25.6 0.26
2,4-D 94-75-7 25.5 27.0 0.2
DBOB (int. std.) 10386-84-2 27.5 27.6 .
Pentachlorophenol 87-86-5 28.3 27.0 0.076
2,4,5-TP 93-72-1 29.7 29.5 0.075
5-Hydroxydicamba 7600-50-2 30.0 30.7 0.04
2,4,5-T 93-76-5 30.5 30.9 0.08
2,4-DB 94-82-6 32.2 32.2 0.8
Bentazon 25057-89-0 33.3 34.6 0.2
Picloram 1918-02-1 34.4 37.5 0.14
C
DCPAAcid Metabolites . 35.8 37.8 0.02
A
Columns and analytical conditions are described in 7.7.1 and 7.7.2
B
Estimated method detection limit, µg/L, determined from 7 replicate analyses of
a reagent water fortified with analyte at a concentration level yielding signal-to-
noise of 5:1. EDL is defined as the standard deviation × student’s t (99 % CI, n –
1 degrees of freedom).
C
DCPA monoacid and diacid metabolites are included in the scope of this test
method; DCPA diacid metabolite is used for validation studies.
FIG. 1 Gaseous Diazomethane Generator
D5317 − 20
7.7 Gas Chromatograph—Analytical system complete with 8.4.3 N-methyl-N-nitroso-paratoluenesulfonamide
temperature programmable GC suitable for use with capillary Solution—Prepare a solution containing 10 g N-methylN-
columns and all required accessories including syringes, ana- nitroso-paratoluenesulfonamide in 100 mLof 50:50 by volume
lytical columns, gases, detector, and stripchart recorder.Adata mixture of ethyl ether and diethylene glycol monoethyl ether.
system is recommended for measuring peak areas. Table 1lists This solution is stable for one month or longer when stored at
retention times observed for test method analytes using the 4°C in an amber bottle with a PTFE-lined screw cap.
columns and analytical conditions described below. 8.4.4 Diethyl Ether, reagent grade, redistilled in glass after
7.7.1 Column 1 (Primary Column), 30-m long by 0.25-mm refluxing over granulated sodium-lead alloy for 4 h.
inside diameter (ID) DB-5 bonded fused silica column, (Warning—Use immediately, or if stored, test for ether
0.25-µm film thickness. Establish helium carrier gas flow at 30 peroxides by test paper, or other suitable means. If present,
cm/s linear velocity and program oven temperature from 60°C repeat reflux and distillation.)
to 300°C at 4°C/m. Data presented in this test method were
8.5 4,4'' Dibromooctafluorobiphenyl (DBOB), 99 % purity,
obtained using this column (Table 1). The injection volume is
for use as internal standard.
2-µL splitless mode with 45 s delay. The injector temperature
8.6 2,4 Dichlorophenylacetic Acid (DCAA), 99 % purity,
is 250°C and the detector is 320°C. Alternative columns may
for use as surrogate standard.
be used in accordance with the provisions described in 19.3.
7.7.2 Column 2 (Confirmation Column), 30-m long by 8.7 Ethyl Acetate, pesticide quality.
0.25-mm I.D. DB-1701 bonded fused silica column, 0.25-µm
8.8 Magnesium Silicate, PR grade (60 to 100 mesh) pur-
film thickness. Establish helium carrier gas flow at 30 cm/s
chased activated at 1250°F (650°C) and continuously stored at
linear velocity and program oven temperature from 60°C to
130°C.
300°C at 4°C/m.
8.9 Glass Wool, acid washed.
7.7.3 Detector, electron capture (ECD). This detector has
proveneffectiveintheanalysisoffortifiedreagentandartificial
8.10 Herbicide Standards—Acids and methyl esters, ana-
ground waters. An ECD was used to generate the validation
lytical reference grade.
data presented in this test method. Alternative detectors,
8.11 Hexane, pesticide quality.
includingamassspectrometer,maybeusedinaccordancewith
8.12 Mercuric Chloride.
the provisions described in 19.3.
8.13 Methyl-t-butyl Ether, pesticide quality.
8. Reagents and Materials
8.14 Methylene Chloride, pesticide quality.
8.1 Purity of Reagents—Reagent grade chemicals shall be
8.15 Potassium Hydroxide Solution (37 g/100 mL)—
used in all tests. Unless otherwise indicated, it is intended that
Dissolve37gofpotassiumhydroxide(KOH)inwater,mixand
all reagents shall conform to the specifications of the Commit-
dilute to 100 mL.
tee onAnalytical Reagents to theAmerican Chemical Society,
8.16 Silicic Acid.
where such specifications are available . Other grades may be
used, provided it is first ascertained that the reagent is of
8.17 Sodium Chloride (NaCl), heat-treated in a shallow tray
sufficiently high purity to permit its use without lessening the
at 450°C for a minimum of 4 h to remove any potential
accuracy of the determination.
interfering organic substances.
8.2 Purity of Water—Except as otherwise indicated, refer-
8.18 Sodium Hydroxide Solution (240 g/L)—Dissolve 240 g
ences to water shall be understood to mean water conforming
of sodium hydroxide (NaOH) in water, mix and dilute to 1 L.
to Specification D1193, Type II. Additionally, the water shall
8.19 Sodium Sulfate, Acidified—Slurry 100 g of the sodium
be free of the interferences described in Section 6.
sulfate that has been heat treated in a shallow tray at 450°C for
8.3 Acetone, pesticide quality.
a minimum of 4 h with sufficient diethyl ether to just cover the
solid.Add0.1mLofconcentratedsulfuricacid(spgr1.84)and
8.4 Diazomethane Esterification Reagents.
mix thoroughly. Remove the ether with vacuum. Ensure that a
8.4.1 Diethylene Glycol Monoethyl Ether, reagent grade.
pH below 4 can be obtained from mixing1gofthe solid with
8.4.2 N-methyl-N-nitroso-paratoluenesulfonamide, ACS
grade. 5 mL of water. Store continuously at 130°C.
8.20 Sodium Thiosulfate, anhydrous (Na S O ), reagent
2 2 3
grade.
ACS Reagent Chemicals, Specifications and Procedures for Reagents and
8.21 Standard Solution, Stock (1.00 µg/µL)—Stock standard
Standard-Grade Reference Materials, American Chemical Society, Washington,
DC. For suggestions on the testing of reagents not listed by theAmerican Chemical
solutions may be purchased as certified solutions or prepared
Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset,
from pure standard materials using the following procedure:
U.K., and the United States Pharmacopeia and National Formulary, U.S. Pharma-
8.21.1 Prepare stock standard solutions by weighing ap-
copeial Convention, Inc. (USPC), Rockville, MD.
Carbitol, a registered trademark of and available from Sigma Chemical Co., proximately 0.0100 g of pure material to three significant
P.O. Box 14508, St Louis, MO 63178-9916, or its equivalent, has been found
suitable for this purpose.
11 12
Diazald, a registered trademark, is available fromAldrich Chemical Company, EM Quant, a trademark of, and available from, EM Laboratories, Inc., 500
Inc., 1001 West Saint Paul Avenue, Milwaukee, WI 53233, and has been found ExecutiveBlvd.,Elmsford,NY10523,oritsequivalent,hasbeenfoundsatisfactory
satisfactory for this purpose. for this purpose.
D5317 − 20
figures.DissolvethematerialinMTBEanddilutetovolumein regulations regarding the safe handling of the chemicals
a 10-mL volumetric flask. Larger volumes may be prepared at specified in this test method.Areference file of material safety
the convenience of the analyst. If compound purity is certified data sheets should also be made available to all personnel
at 96 % or greater, the weight may be used without correction involved in the chemical analysis. Additional references to
to calculate the concentration of the stock standard. Commer- laboratory safety are available and have been identified (29
cially prepared stock standards may be used at any concentra- CFR 1910) (5, 6) for the information of the analyst.
tion if they are certified by the manufacturer or by an
9.2 Diazomethane—A toxic carcinogen that can explode
independent source.
under certain conditions. The following precautions must be
8.21.2 Transfer the stock standard solutions into PTFE
followed:
sealed screw-cap amber vials. Store at room temperature and
9.2.1 Use only a well ventilated hood—do not breathe
protect from light.
vapors.
8.21.3 Replace stock standard solutions after two months or
9.2.2 Use a safety screen.
sooner if comparison with laboratory fortified blanks, or
9.2.3 Use mechanical pipetting aids.
quality control sample indicates a problem.
9.2.4 Do not heat above 90°C—Explosion may result.
8.22 Standard Solution, Internal—Prepare an internal stan-
9.2.5 Avoid grinding surfaces, ground glass joints, sleeve
dard solution by accurately weighing approximately 0.0010 g
bearings, glass stirrers—Explosion may result.
of pure DBOB. Dissolve the DBOB in MTBE and dilute to
9.2.6 Store away from alkali metals—Explosion may result.
volume in a 10-mL volumetric flask. Transfer the internal
9.2.7 Solutions of diazomethane decompose rapidly in the
standard solution to a PTFE sealed screw cap bottle and store
presence of solid materials such as copper powder, calcium
atroomtemperature.Additionof25µLoftheinternal standard
chloride, and boiling chips.
solution to 10 mL of sample extract results in a final internal
9.2.8 The diazomethane generation apparatus used in the
standard concentration of 0.25 µg/mL. Solution should be
esterificationprocedures13.2producesmicromolaramountsof
replaced when ongoing quality control in Section 19 indicates
diazomethane to minimize safety hazards.
a problem. Note that DBOB has been shown to be an effective
9.3 Ethyl Ether, pesticide quality, redistilled in glass, if
internal standard for the test method analytes (4), but other
necessary.
compounds may be used if the quality control requirements in
9.3.1 Ethyl ether is an extremely flammable solvent. If a
Section 19 are met.
mechanical device is used for sample extraction, the device
8.23 Surrogate Standard Solution—Prepare a surrogate
should be equipped with an explosion-proof motor and placed
standard solution by weighing approximately 0.0010 g of pure
in a hood to avoid possible damage and injury due to an
DCAA to three significant figures. Dissolve the DCAA in
explosion.
MTBE and dilute to volume in a 10-mL volumetric flask.
9.3.2 Must be free of peroxides as indicated by test strips.
Transfer the surrogate standard solution to a PTFE sealed
(Warning—When a solvent is purified, stabilizers added by
screw cap bottle and store at room temperature.Addition of 50
the manufacturer are removed, thus potentially making the
µL of the surrogate standard solution to a 1-L sample prior to
solvent hazardous.)
extraction results in a surrogate standard concentration in the
sample of 5 µg/L and, assuming quantitative recovery of
10. Sample Collection, Preservation, and Storage
DCAA, a surrogate standard concentration in the final extract
10.1 CollectthesampleinaccordancewithPracticesD3370
of 0.5 µg/mL. Solution should be replaced when ongoing
inanamberglassbottle.Donotprerinsethebottlewithsample
quality control described in Section 19 indicates a problem.
before collection.
NOTE 1—DCAA has been shown to be an effective surrogate standard
10.2 Add mercuric chloride to the sample bottle in an
for the method analytes (4), but other compounds may be used if the
amount to produce a concentration of 10 mg HgCl by adding
quality control requirements in 19.4 are met.
1 mL of a 10 mg HgCl/mL solution to the sample bottle at the
8.24 Sulfuric Acid Solution (335 + 665)—Carefully add,
sampling site, or in the laboratory before shipping to the
with constant mixing, 335 mL of concentrated sulfuric acid to
samplingsite. (Warning—Mercuricchlorideishighlytoxic.If
665 mL of water.
the use of another bacteriacide can be shown to be equivalent
8.25 Toluene, pesticide quality.
to HgCl , it can be used provided all quality control criteria in
8.26 Hydrochloric Acid (HCl) (1 + 9)—Carefully add, with Sections 18 and 19 are met.)
constant mixing, 100 mL of concentrated HCl to 900 mL of
10.3 Test for the presence of chlorine with potassium
water.
iodide-starch test paper previously moistened with dilute acid.
Darkening of the test paper indicates the presence of chlorine
9. Hazards
(and a few other oxidizing materials). Add 80 mg Na S O to
2 2 3
9.1 The toxicity or carcinogenicity of each reagent used in
the bottle before adding the sample.
this test method has not been precisely defined; however, each
10.4 After the sample is collected in the bottle containing
chemical compound must be treated as a potential health
preservative, seal the bottle and shake vigorously for 1 min.
hazard. Accordingly, exposure to these chemicals must be
reduced to the lowest possible level. The laboratory is respon- 10.5 Immediately store the sample at 4°C away from light
sible for maintaining a current awareness file of OSHA until extraction. Preservation study results indicate that the
D5317 − 20
analytes (measured as total acid) present in samples are stable point standards at a concentration that produces a response that
for 14 days when stored under these conditions (4). However, deviates from the sample extract response by no more than
analyte stability may be affected by the matrix; therefore, the
20 %.
analyst should verify that the preservation technique is appli-
11.2.6 Verify calibration standards periodically, at least
cable to the samples under study.
quarterly is recommended, by analyzing a standard prepared
from reference material obtained from an independent source.
11. Calibration
Results from these analyses must be within the limits used to
11.1 Establish GC operating parameters equivalent to those
routinely check calibration.
indicated in 7.7.The GC system may be calibrated using either
11.3 External Standard Calibration Procedure:
the internal standard technique (11.2) or the external standard
11.3.1 Prepare calibration standards at a minimum of three
technique (11.3).
(five are recommended) concentration levels for each analyte
NOTE 2—Calibration standard solutions must be prepared such that no
of interest and surrogate compound by adding volumes of one
unresolved analytes are mixed together.
or more stock standards and 250-µL methanol to a volumetric
11.2 Internal Standard Calibration Procedure—Select one
flask. Dilute to volume with MTBE. Esterify acids with
or more internal standards compatible in analytical behavior to
diazomethane (13.2 or 13.3). The lowest standard should
the compounds of interest. Demonstrate that the measurement
representanalyteconcentrationsnear,butabove,therespective
of the internal standard is not affected by test method or matrix
EDL (Table 1). The remaining standards should bracket the
interferences. DBOB has been identified as a suitable internal
analyte concentrations expected in the sample extracts, or
standard.
should define the working range of the detector.
11.2.1 Prepare calibration standards at a minimum of three
11.3.2 Starting with the standard of lowest concentration,
(five are recommended) concentration levels for each analyte
analyze each calibration standard according to Section 16 and
of interest by adding volumes of one or more stock standards
tabulateresponse(peakheightorarea)versustheconcentration
to a volumetric flask. To each calibration standard, add a
curveforeachcompound.Alternatively,iftheratioofresponse
known constant amount of one or more of the internal
to concentration (calibration factor) is a constant over the
standards and 250-µL methanol, and dilute to volume with
working range (20 % RSD or less), assume linearity through
MTBE. Esterify acids with diazomethane as described in 13.2
the origin and put the average ratio or calibration factor in
or 13.3. The lowest standard should represent analyte concen-
place of a calibration curve.
trations near, but above, the respective estimated detection
11.3.3 Verify the working calibration curve or calibration
levels (EDLs). The remaining standards should bracket the
factor on each working day by the measurement of a minimum
analyte concentrations expected in the sample extracts, or
of two calibration check standards, one at the beginning and
should define the working range of the detector (Table 1).
one at the end of the analysis day. These check standards
11.2.2 Analyze each calibration standard according to the
should be at two different concentration levels to verify the
procedure(Section16).Tabulateresponse(peakheightorarea)
calibration curve. For extended periods of analysis (greater
againstconcentrationforeachcompoundandinternalstandard.
than 8 h), it is strongly recommended that check standards be
Calculate the response factor (RF) for each analyte and
interspersedwithsamplesatregularintervalsduringthecourse
surrogate using the following equation:
of the analyses. If the response is by more than 620 %, repeat
~A !~C !
s is
RF 5 (1) the test using a fresh calibration standard. If the results still do
~A !~C !
is s
not agree, generate a new calibration curve or use a single-
where:
point calibration standard as described in 11.3.4.
A = response for the analyte to be measured,
s 11.3.4 Single-point calibration is a viable alternative to
A = response for the internal standard,
is calibration curve. Prepare single-point standards from the
C = concentration of the internal standard, µg/L, and
is
secondary dilution standards in MTBE. Prepare the single-
C = concentration of the analyte to be measured, µg/L.
s
point standards at a concentration that produces a response that
11.2.3 If the RF value over the working range is constant deviates from the sample extract response by no more than
(20 % RSD or less) use the average RF for calculations. 20 %.
Alternatively, use the results to plot a calibration curve of
11.3.5 Verify calibration standards periodically, recommend
response ratios (A /A ) versus C .
s is s at least quarterly, by analyzing a standard prepared from
11.2.4 Verify the working calibration curve or RF on each
reference material obtained from an independent source. Re-
working shift by the measurement of one or more calibration
sults from these analyses must be within the limits used to
standards. If the response for any analyte varies from the
routinely check calibration.
predicted response by more than 620 %, repeat the test using
afreshcalibrationstandard.Iftherepetitionalsofails,generate
12. Procedure
a new calibration curve for that analyte using freshly prepared
12.1 Manual Hydrolysis, Preparation, and Extraction:
standards.
11.2.5 Single-point calibration is a viable alternative to a 12.1.1 Add preservative to every blank sample and quality-
calibration curve. Prepare single point standards from the control check the standard. Mark the water meniscus on the
secondary dilution standards in MTBE. Prepare the single side of the sample bottle for later determination of sample
D5317 − 20
volume (12.1.9). Pour the entire sample into a 2-L separatory 12.2 Automated Hydrolysis, Preparation, and Extraction:
funnel. Fortify sample with 50 µL of the surrogate standard
12.2.1 Follow the fortification and preservation procedures
solution.
given in 12.1.1. If the mechanical separatory funnel shaker is
12.1.2 Add 250 g NaCl to the sample, seal, and shake to
used, pour the entire sample into a 2-Lseparatory funnel. If the
dissolve salt.
mechanical tumbler is used, pour the entire sample into a
12.1.3 Add 17 mL of NaOH solution (240 g/L) to the
tumbler bottle.
sample, seal, and shake. Check the pH of the sample with pH
12.2.2 Add 250 g of NaCl to the sample, seal, and shake to
paper; if the sample does not have a pH greater than or equal
dissolve salt.
to 12, adjust the pH by adding more NaOH (240 g/L). Let the
12.2.3 Add 17 mL of NaOH solution (240 g/L) to the
sample sit at room temperature for 1 h, and shake the
sample, seal, and shake. Check the pH of the sample with pH
separatory funnel and contents periodically.
paper; if the sample does not have a pH greater than or equal
12.1.4 Add 60-mL methylene chloride to the sample bottle
to 12, adjust the pH by adding more NaOH (240 g/L). Shake
to rinse the bottle. Transfer the methylene chloride to the
samplefor1husingtheappropriatemechanicalmixingdevice.
separatoryfunnelandextractthesamplebyvigorouslyshaking
12.2.4 Add 300 mLmethylene chloride to the sample bottle
the funnel for 2 min with periodic venting to release excess
to rinse the bottle, transfer the methylene chloride to the
pressure. Allow the organic layer to separate from the water
separatory funnel or tumbler bottle, seal, and shake for 10 s,
phase for a minimum of 10 min. If the emulsion interface
venting periodically. Repeat shaking and venting until pressure
betweenlayersismorethanone-thirdthevolumeofthesolvent
release is not observed during venting. Reseal and place
layer, the analyst must employ mechanical techniques to
sample container in appropriate mechanical mixing device.
complete the phase separation. The optimum technique de-
Shake or tumble the sample for 1 h. Complete and thorough
pends upon the sample, but may include stirring, filtration
mixing of the organic and aqueous phases should be observed
through glass wool, centrifugation, or other physical methods.
at least 2 min after starting the mixing device.
Discard the methylene chloride phase.
12.2.5 Remove the sample container from the mixing de-
12.1.5 Add a second 60 mL volume of methylene chloride
vice.Ifthetumblerisused,pourcontentsoftumblerbottleinto
to the sample bottle and repeat the extraction procedure a
a 2-L separatory funnel. Allow the organic layer to separate
second time, discarding the methylene chloride layer. Perform
fromthewaterphaseforaminimumof10min.Iftheemulsion
a third extraction in the same manner.
interface between layers is more than one third the volume of
12.1.6 Add 17 mL of H SO solution (335 + 665) to the
2 4
the solvent layer, the analyst must employ mechanical tech-
sample, seal, and shake to mix. Check the pH of the sample
niques to complete the phase separation. The optimum tech-
with pH paper; if the sample does not have a pH less than or
nique depends upon the sample, but may include stirring,
equal to 2, adjust the pH by adding more H SO solution
2 4
filtration through glass wool, centrifugation, or other physical
(335 + 665).
methods. Drain and discard the organic phase. If the tumbler is
12.1.7 Add 120-mL ethyl ether to the sample, seal, and
used, return the aqueous phase to the tumbler bottle.
extract the sample by vigorously shaking the funnel for 2 min
12.2.6 Add 17 mL of H SO solution (335 + 665) to the
2 4
with periodic venting to release excess pressure. Allow the
sample, seal, and shake to mix. Check the pH of the sample
organic layer to separate from the water phase for a minimum
with pH paper; if the sample does not have a pH less than or
of 10 min. If the emulsion interface between layers is more
equal to 2, adjust the pH by adding more H SO solution
2 4
than one third the volume of the solvent layer, the analyst must
(335 + 665).
employ mechanical techniques to complete the phase separa-
12.2.7 Add 300-mL ethyl ether to the sample, seal, and
tion. The optimum technique depends upon the sample, but
shake for 10 s, venting periodically. Repeat shaking and
may include stirring, filtration through glass wool,
venting until pressure release is not observed during venting.
centrifugation,orotherphysicalmethods.Removetheaqueous
Reseal and place sample container in appropriate mechanical
phase to a 2-L Erlenmeyer flask and collect the ethyl ether
mixing device. Shake or tumble sample for 1 h. Complete and
phase in either a 500-mL round-bottom flask or a 500-mL
thorough mixing of the organic and aqueous phases should be
Erlenmeyer flask containing approximately 10 g of acidified
observed at least 2 min after starting the mixing device.
anydrous sodium sulfate. Periodically, vigorously shake the
12.2.8 Remove the sample container from the mixing de-
sampleanddryingagent.Allowtheextracttoremainincontact
vice.Ifthetumblerisused,pourcontentsoftumblerbottleinto
with the sodium sulfate for approximately 2 h.
a 2-L separatory funnel. Allow the organic layer to separate
12.1.8 Return the aqueous phase to the separatory funnel,
fromthewaterphaseforaminimumof10min.Iftheemulsion
add a 60-mL volume of ethyl ether to the sample, and repeat
interface between layers is more than one third the volume of
the extraction procedure a second time, combining the extracts
the solvent layer, the analyst must employ mechanical tech-
in the 500-mL round-bottom or Erlenmeyer flask. Perform a
niques to complete the phase separation. The optimum tech-
third extraction with 60 mL of ethyl ether in the same manner.
nique depends upon the sample, but may include stirring,
12.1.9 Determine the original sample volume by refilling
filtration through glass wool, centrifugation, or other physical
the sample bottle to the mark and transferring the water to a
methods. Drain and discard the aqueous phase. Collect the
1000-mLgraduated cylinder. Record the sample volume to the
extract in a 500-mL Erlenmeyer or round-bottom flask con-
nearest 5 mL.
taining about 10 g of acidified anhydrous sodium sulfate.
Periodically, vigorously shake the sample and drying agent.
D5317 − 20
Allow the extract to remain in contact with the sodium sulfate mixture should be used to esterify only two samples; prepare
for approximately 2 h. new reaction mixture in Tube 2 to esterify each two additional
12.2.9 Determine the original sample volume by refilling samples. Samples should turn yellow after addition of diaz-
the sample bottle to the mark and transferring the water to a omethane and remain yellow for at least 2 min. The presence
1000-mLgraduated cylinder. Record the sample volume to the of color or particulates can obscure the yellow color in some
nearest 5 mL. samples. Evolution of N gas in 13.3.5 will indicate that
sufficient diazomethane was present to complete the reaction.
12.3 Extract Concentration:
Repeat methylation procedure if necessary.
12.3.1 Assemble a K-D Concentrator by attaching a con-
13.2.3 Seal concentrator tubes with stoppers. Store at room
centrator tube to a 500-mL evaporative flask.
temperature in a hood for 30 min.
12.3.2 Pour the dried extract through a funnel plugged with
13.2.4 Destroy any unreacted diazomethane by adding 0.1
acid-washed glass wool, and collect the extract in the K-D
to 0.2 g silicic acid to the concentrator tubes. Allow to stand
concentrator.Useaglassrodtocrushanycakedsodiumsulfate
until the evolution of nitrogen has stopped (approximately 20
duringthetransfer.Rinsetheflaskandfunnelwith20to30mL
min). Adjust the sample volume to 5.0 mL with MTBE.
of ethyl ether to complete the quantitative transfer.
12.3.3 Add 1 to 2 clean boiling stones to the evaporative 13.3 Diazomethane Solution Procedure:
flask and attach a macro-Snyder column. Prewet the Snyder 13.3.1 Assemble the diazomethane generator (Fig. 2)ina
column by adding about 1 mL ethyl ether to the top. Place the hood. The collection vessel is a 10 or 15-mL vial, equipped
K-D apparatus on a hot water bath, 60 to 65°C, so that the with a PTFE-lined screw cap and maintained at 0 to 5°C.
concentrator tube is partially immersed in the hot water, and 13.3.2 Add a sufficient amount of ethyl ether to tube 1 to
the entire lower rounded surface of the flask is bathed with hot cover the first impinger. Add 5 mL of MTBE to the collection
vapor. At the proper rate of the distillation the balls of the vial. Set the nitrogen flow at 5 to 10 mL/min. Add 2 mL
column will actively chatter, but the chambers will not flood. N-methyl-N-nitroso-paratoluenesulfonamide solution (8.4.3)
When the apparent volume of liquid reaches 1 mL, remove the and 1.5 mL of KOH (37 g/100 mL) solution to the second
K-D apparatus and allow it to drain and cool for at least 10 impinger. Connect the tubing as shown and allow the nitrogent
min. flow to purge the diazomethane from the reaction vessel into
12.3.4 RemovetheSnydercolumnandrinsetheflaskandits the collection vial for 30 min. The vial should be sealed with
lower joint into the concentrator tube with 1 to 2 mL of ethyl PTFE-lined cap and the vial stored inside a sealed glass vessel.
ether. Add 2 mL of MTBE and a fresh boiling stone. Attach a When stored at 0 to 5°C, this diazomethane solution may be
micro–Snyder column to the concentration tube and prewet the used over a period of 48 h.
column by adding about 0.5 mLof ethyl ether to the top. Place 13.3.3 To each concentrator tube containing sample or
the micro K-D apparatus on the water bath so that the standard, add 0.5 mL diazomethane solution. Samples should
concentrator tube is partially immersed in the hot water.Adjust turn yellow after addition of the diazomethane solution and
the vertical position of the apparatus and the water temperature remain yellow for at least 2 min. Repeat methylation
as required to complete concentration in 5 to 10 min.When the procedure, if necessary, no more than once.
apparent volume of liquid reaches 0.5 mL, remove the micro 13.3.4 Seal concentrator tubes with stoppers. Store at room
K-Dfromthebathandallowittodrainandcool.Ifthegaseous temperature in a hood for 30 min.
diazomethane procedure (13.2) is to be used for esterification, 13.3.5 Destroy any unreacted diazomethane by adding 0.1
rinse the walls of the concentrator tube while adjusting the to 0.2 grams silicic acid to the concentrator tubes. Allow to
volume to 5.0 mL with MTBE. If diazomethane solution is to stand until the evolution of nitrogen has stopped (approxi-
be used (13.3) rinse the walls of the concentrator tube while mately 20 min). Adjust the sample volume to 5.0 mL with
adjusting the volume to 4.5 mL with MTBE. MTBE.
13. Esterification
13.1 Two methods are described for using diazomethane as
the esterifications reagent.
13.2 Gaseous Diazomethane Procedure:
13.2.1 Assemble the diazomethane generator (Fig. 1)ina
hood.
13.2.2 Add5mLofethylethertoTube1.Add1mLofethyl
ether, 1 mL of carbitol, 1.5 mL of aqueous KOH solution (37
g/100 mL), and 0.2 g N-methyl-N-nitroso-
paratoluenesulfonamide to Tube 2. Immediately place the exit
tube into the concentrator tube containing the sample extract.
Apply nitrogen flow (10 mL/min) to bubble diazomethane
through the extract for 1 min. Remove first sample. Rinse the
tip of the diazomethane generator with ethyl ether after
methylation of each sample. Bubble diazomethane through the
second sample extract for 1 min. Diazomethane reaction FIG. 2 Diazomethane Solution Generator
D5317 − 20
14. Magnesium Silicate Separation times the standard deviation of a retention time to calculate a
suggested window size for a compound. However, the ex
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5317 − 98 (Reapproved 2017) D5317 − 20
Standard Test Method for
Determination of Chlorinated Organic Acid Compounds in
Water by Gas Chromatography with an Electron Capture
Detector
This standard is issued under the fixed designation D5317; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers a gas chromatographic procedure for the quantitative determination of selected chlorinated acids and
other acidic herbicides in water. Similar chemicals may also be determined by this test method, but it is the user’suser’s
responsibility to verify the applicability of this test method to any compounds not listed in this scope. The acid form of the
following compounds were interlaboratory tested using this test method, and the results were found acceptable:
Chemical Abstract Services
Analyte
Registry Number
Bentazon 25057-89-0
2,4-D 94-75-7
2,4-DB 94-82-6
DCPA acid metabolites
Dicamba 1918-00-9
3,5-Dichlorobenzoic acid 51-36-5
Dichlorprop 120-36-5
5-Hydroxydicamba 7600-50-2
Pentachlorophenol (PCP) 87-86-5
Picloram 1918-02-1
2,4,5-T 93-76-5
2,4,5-TP (Silvex) 93-72-1
1.2 This test method may be applicable to the determination of salts and esters of analyte compounds. The form of each acid is
not distinguished by this test method. Results are calculated and reported for each listed analyte as the total free acid.
1.3 This test method has been validated in an interlaboratory test for reagent water and finished tap water. The analyst should
recognize that precision and bias reported in Section 18 may not be applicable to other waters.
1.4 This test method is restricted to use by or under the supervision of analysts experienced in the use of gas chromatography (GC)
and in the interpretation of gas chromatograms. Each analyst must demonstrate the ability to generate acceptable results with this
test method using the procedure described in 19.3. It is the user’suser’s responsibility to ensure the validity of this test method for
waters of untested matrices.
This test method is under the jurisdiction of ASTM Committee D19 on Water and is the direct responsibility of Subcommittee D19.06 on Methods for Analysis for
Organic Substances in Water.
Current edition approved Dec. 15, 2017Aug. 15, 2020. Published January 2018August 2020. Originally approved in 1992. Last previous edition approved in 20112017
as D5317 – 93 (2011).D5317 – 98 (2017). DOI: 10.1520/D5317-98R17.10.1520/D5317-20.
DCPA monoacid and diacid metabolites are included in the scope of this test method; DCPA diacid metabolite is used for validation studies.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5317 − 20
1.5 Analytes that are not separated chromatographically, that is, which have very similar retention times, cannot be individually
identified and measured in the same calibration mixture or water sample unless an alternate technique for identification and
quantitation exists (16.6, 16.7, and 16.8).
1.6 When this test method is used to analyze unfamiliar samples for any or all of the analytes given in 1.1, analyte identifications
must be confirmed by at least one additional qualitative technique.
1.7 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to
inch-pound units that are provided for information only and are not considered No other units of measurement are included in this
standard.
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use. For specific warning statements, see Sections 6, 8, 9, and 10.
1.9 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D1129 Terminology Relating to Water
D1193 Specification for Reagent Water
D2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water
D3370 Practices for Sampling Water from Flowing Process Streams
D3856 Guide for Management Systems in Laboratories Engaged in Analysis of Water
D4210 Practice for Intralaboratory Quality Control Procedures and a Discussion on Reporting Low-Level Data (Withdrawn
2002)
D5789 Practice for Writing Quality Control Specifications for Standard Test Methods for Organic Constituents (Withdrawn
2002)
2.2 EPA Standard:
Method 515.1 Revision 4.0, Methods for the Determination of Organic Compounds in Drinking Water
2.3 OSHA Standard:
29 CFR 1910 OSHA Safety and Health Standards, General Industry
3. Terminology
3.1 Definitions:
3.1.1 For definitions of terms used in this standard, refer to Terminology D1129.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 internal standard, n—a pure analyte(s) added to a solution in known amount(s) and used to measure the relative responses
of other method analytes and surrogates that are components of the same solution.
3.2.1.1 Discussion—
The internal standard must be an analyte that is not a sample component.
3.2.2 surrogate analyte, n—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 and is measured with the same procedures used to measure other sample
components.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’sstandard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
Available from United States Environmental Protection Agency (EPA), William Jefferson Clinton Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460,
http://www.epa.gov.
Available from U.S. Government Printing Office, Superintendent of Documents, 732 N. Capitol St., NW, Washington, DC 20401-0001, http://www.access.gpo.gov.
D5317 − 20
3.2.2.1 Discussion—
The purpose of a surrogate analyte is to monitor method performance with each sample.
4. Summary of Test Method
4.1 The compounds listed in 1.1, in water samples, are converted into sodium salts by adjusting the pH to 12 with sodium
hydroxide solution (240 g/L) and shaking for 1 h. Extraneous neutral material is removed by extraction with methylene chloride.
The sample is acidified, the acids are extracted with ethyl ether and converted to methyl esters using diazomethane. After the excess
reagent is removed, the methyl esters are determined by capillary column GC using an electron capture (EC) detector. Other
detection systems, such as microcoulometric and electrolytic conductivity, are not as sensitive as EC for measurement of
chlorinated acid esters but are more specific and less subject to interferences. A mass spectrometer may also be used as a detector.
4.2 This test method provides a magnesium silicate cleanup procedure to aid in the elimination of interferences that may be
present.
5. Significance and Use
5.1 Chlorinated phenoxyacid herbicides, and other organic acids are used extensively for weed control. Esters and salts of 2,4-D
and silvex have been used as aquatic herbicides in lakes, streams, and irrigation canals. Phenoxy acid herbicides can be toxic even
at low concentrations. For example, the 96 h, TL for silvex is 2.4 mg/L for bluegills (1). These reasons make apparent the need
m
for a standard test method for such compounds in water.
6. Interferences
6.1 Method interferences may be caused by contaminants in solvents, reagents, glassware and other sample processing apparatus
that lead to discrete artifacts or elevated baselines in gas chromatograms. All reagents and apparatus must be routinely
demonstrated to be free from interferences under the conditions of the analysis by running laboratory reagent blanks as described
in 19.2.
6.1.1 Glassware must be scrupulously cleaned (2). 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 dilute acid, tap, and reagent
water. Drain dry, and heat in an oven or muffle furnace at 400°C for 1 h. Do not heat volumetric ware. Thorough rinsing with
acetone may be substituted for the heating. After drying and cooling, seal and store glassware in a clean environment to prevent
any accumulation of dust or other contaminants. Store inverted or capped with aluminum foil. Thermally stable materials such as
PCBs may not be eliminated by this treatment.
6.1.2 The use of high purity reagents and solvents helps to minimize interference problems. Purification of solvents by distillation
in all-glass systems may be required. (Warning—When a solvent is purified, stabilizers added by the manufacturer are removed,
thus potentially making the solvent hazardous. Also, when a solvent is purified, preservatives added by the manufacturer are
removed, thus potentially reducing the shelf-life.)
6.2 The acid forms of the analytes are strong organic acids that react readily with alkaline substances and can be lost during sample
preparation. Glassware and glass wool must be acid-rinsed with hydrochloric acid (1 + 9) and the sodium sulfate must be acidified
with sulfuric acid prior to use to avoid analyte loses due to adsorption.
6.3 Organic acids and phenols, especially chlorinated compounds, cause the most direct interference with the determination.
Alkaline hydrolysis and subsequent extraction of the basic sample removes many chlorinated hydrocarbons and phthalate esters
that might otherwise interfere with the electron capture analysis.
6.4 Interferences by phthalate esters can pose a major problem in pesticide analysis when using the ECD. These compounds
generally appear in the chromatogram as large peaks. Common flexible plastics contain varying amounts of phthalates, which are
easily extracted or leached during laboratory operations. Cross contamination of clean glassware routinely occurs when plastics
are handled during extraction steps, especially when solvent-wetted surfaces are handled. Interferences from phthalates can best
Florisil, a trademark of, and available from, Floridin Co., 2 Gateway Center, Pittsburgh, PA 15222, or its equivalent, has been found satisfactory for this purpose.
The boldface numbers in parentheses refer to the list of references at the end of this test method.
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be minimized by avoiding the use of plastics in the laboratory. Exhaustive purification of reagents and glassware may be required
to eliminate background phthalate contamination (3).
6.5 Interfering contamination may occur when a sample containing low concentrations of analytes is analyzed immediately
following a sample containing relatively high concentrations of analytes. Between-sample rinsing of the sample syringe and
associated equipment with methyl-t-butyl-ether (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.
6.6 Matrix interferences may be caused by contaminants that are coextracted from the sample. Also, note that all analytes listed
in Table 1 are not resolved from each other on any one column, that is, one analyte of interest may be an interferent for another
analyte of interest. The extent of matrix interferences will vary considerably from source to source, depending upon the water
sampled. The procedures in Section 16 can be used to overcome many of these interferences. Positive identifications should be
confirmed. See 16.6, 16.7, and 16.8.
6.7 It is important that samples and working standards be contained in the same solvent. The solvent for working standards must
be the same as the final solvent used in sample preparation. If this is not the case, chromatographic comparability of standards to
sample may be affected.
7. Apparatus and Equipment
7.1 Sample Bottle—Borosilicate amber, 1-L volume with graduations, fitted with screw caps lined with TFE-fluorocarbon.
polytetrafluoroethylene (PTFE). Protect samples from light. The container must be washed and dried as described in 6.1.1 before
use to minimize contamination. Cap liners are cut to fit from sheets and extracted with methanol overnight prior to use.
7.2 Glassware.
7.2.1 Separatory funnel,Funnel, 2000-mL, with TFE-fluorocarbonPTFE stopcocks, ground glass or TFE-fluorocarbonPTFE
stoppers.
7.2.2 Tumbler bottle,Bottle, 1.7-L with TFE-fluorocarbon lined PTFE-lined screw cap. Cap liners are cut to fit from sheets and
extracted with methanol overnight prior to use.
TABLE 1 Retention Times and Estimated Method Detection
Limits for Method Analytes
A
Retention Time (min)
B
Analyte CAS No. EDLEDL
Primary Confirmation
3,5-Dichlorobenzoic acid 51-36-5 18.6 17.7 0.061
3,5-Dichlorobenzoic Acid 51-36-5 18.6 17.7 0.061
DCAA (surrogate) 19719-28-9 22.0 14.9 .
Dicamba 1918-00-9 22.1 22.6 0.081
Dichlorprop 120-36-5 25.0 25.6 0.26
2,4-D 94-75-7 25.5 27.0 0.2
DBOB (int. std.) 10386-84-2 27.5 27.6 .
Pentachlorophenol 87-86-5 28.3 27.0 0.076
2,4,5-TP 93-72-1 29.7 29.5 0.075
5-Hydroxydicamba 7600-50-2 30.0 30.7 0.04
2,4,5-T 93-76-5 30.5 30.9 0.08
2,4-DB 94-82-6 32.2 32.2 0.8
Bentazon 25057-89-0 33.3 34.6 0.2
Picloram 1918-02-1 34.4 37.5 0.14
C
DCPA acid metabolites . 35.8 37.8 0.02
C
DCPA Acid Metabolites . 35.8 37.8 0.02
A
Columns and analytical conditions are described in 7.7.1 and 7.7.2
B
Estimated method detection limit, μg/L, determined from 7 replicate analyses of
a reagent water fortified with analyte at a concentration level yielding signal-to-
noise of 5:1. EDL is defined as the standard deviation × student’s t (99 % CI, n –
1 degrees of freedom).
C
DCPA monoacid and diacid metabolites are included in the scope of this test
method; DCPA diacid metabolite is used for validation studies.
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7.2.3 Concentrator tube,Tube, Kuderna-Danish (K-D), 10 or 25-mL, graduated. Calibration must be checked at the volumes
employed in the procedure. Ground-glass stoppers are used to prevent evaporation of extracts.
7.2.4 Evaporative flask,Flask, K-D, 500-mL. Attach to concentrator tube with springs.
7.2.5 Snyder column,Column, K-D, three ball macro.
7.2.6 Snyder column,Column, K-D, two ball micro.
7.2.7 Flask, round bottom, 500-mL with 24/40 ground glass joint.
7.2.8 Vials, glass, 5 to 10-mL capacity with TFE-fluorocarbon lined PTFE-lined screw cap.
7.3 Boiling Stone, TFE-fluorocarbon.PTFE.
7.4 Water Bath, heated, capable of temperature control (62°C). The bath should be used in a hood.
7.5 Diazomethane Generator—Assemble from two 20- by 155-mm test tubes, two neoprene rubber stoppers, and a source of
nitrogen as shown in Fig. 1.
7.6 Glass Wool, acid washed and heated at 450°C.
7.7 Gas Chromatograph—Analytical system complete with temperature programmable GC suitable for use with capillary columns
and all required accessories including syringes, analytical columns, gases, detector, and stripchart recorder. A data system is
recommended for measuring peak areas. Table 1lists retention times observed for test method analytes using the columns and
analytical conditions described below.
7.7.1 Column 1 (Primary Column), 30-m long by 0.25-mm inside diameter (ID) DB-5 bonded fused silica column, 0.25-μm film
thickness. Establish helium carrier gas flow at 30 cm/s linear velocity and program oven temperature from 60°C to 300°C at 4°C/m.
Data presented in this test method were obtained using this column (Table 1). The injection volume is 2-μL splitless mode with
45 s delay. The injector temperature is 250°C and the detector is 320°C. Alternative columns may be used in accordance with the
provisions described in 19.3.
7.7.2 Column 2 (Confirmation Column), 30-m long by 0.25-mm I.D. DB-1701 bonded fused silica column, 0.25-μm film
thickness. Establish helium carrier gas flow at 30 cm/s linear velocity and program oven temperature from 60°C to 300°C at 4°C/m.
FIG. 1 Gaseous Diazomethane Generator
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7.7.3 Detector, electron capture (ECD). This detector has proven effective in the analysis of fortified reagent and artificial ground
waters. An ECD was used to generate the validation data presented in this test method. Alternative detectors, including a mass
spectrometer, may be used in accordance with the provisions described in 19.3.
8. Reagents and Materials
8.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all
reagents shall conform to the specifications of the Committee on Analytical Reagents to the American Chemical Society, where
such specifications are available . Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high
purity to permit its use without lessening the accuracy of the determination.
8.2 Purity of Water—Except as otherwise indicated, references to water shall be understood to mean water conforming to
Specification D1193, Type II. Additionally, the water shall be free of the interferences described in Section 6.
8.3 Acetone, pesticide quality.
8.4 Diazomethane Esterification Reagents.
8.4.1 Diethylene Glycol Monoethyl Ether, reagent grade.
8.4.2 N-methyl-N-nitroso-paratoluenesulfonamide, ACS grade.
8.4.3 N-methyl-N-nitroso-paratoluenesulfonamide solution—Solution—Prepare a solution containing 10 g N-methylN-nitroso-
paratoluenesulfonamide in 100 mL of 50:50 by volume mixture of ethyl ether and diethylene glycol monoethyl ether. This solution
is stable for one month or longer when stored at 4°C in an amber bottle with a TFE-fluorocarbon-linedPTFE-lined screw cap.
8.4.4 Diethyl Ether, reagent grade, redistilled in glass after refluxing over granulated sodium-lead alloy for 4 h. (Warning—Use
immediately, or if stored, test for ether peroxides by test paper, or other suitable means. If present, repeat reflux and distillation.)
8.5 4,4'' Dibromooctafluorobiphenyl (DBOB), 99 % purity, for use as internal standard.
8.6 2,4 Dichlorophenylacetic Acid (DCAA), 99 % purity, for use as surrogate standard.
8.7 Ethyl Acetate, pesticide quality.
8.8 Magnesium Silicate, PR grade (60 to 100 mesh) purchased activated at 1250°F (650°C) and continuously stored at 130°C.
8.9 Glass Wool, acid washed.
8.10 Herbicide Standards—Acids and methyl esters, analytical reference grade.
8.11 Hexane, pesticide quality.
8.12 Mercuric chloride.Chloride.
Reagent Chemicals, American Chemical Society Specifications,ACS Reagent Chemicals, Specifications and Procedures for Reagents and Standard-Grade Reference
Materials, American Chemical Society, Washington, DC, www.chemistry.org. DC. For suggestions on the testing of reagents not listed by the American Chemical Society,
see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and National Formulary, U.S. Pharmacopeial
Convention, Inc. (USPC), Rockville, MD, http://www.usp.org.MD.
Carbitol, a registered trademark of and available from Sigma Chemical Co., P.O. Box 14508, St Louis, MO 63178-9916, or its equivalent, has been found suitable for
this purpose.
Diazald, a registered trademark, is available from Aldrich Chemical Company, Inc., 1001 West Saint Paul Avenue, Milwaukee, WI 53233, and has been found satisfactory
for this purpose.
EM Quant, a trademark of, and available from, EM Laboratories, Inc., 500 Executive Blvd., Elmsford, NY 10523, or its equivalent, has been found satisfactory for this
purpose.
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8.13 Methyl-t-butyl Ether, pesticide quality.
8.14 Methylene Chloride, pesticide quality.
8.15 Potassium Hydroxide Solution (37 g/100 mL)—Dissolve 37 g of potassium hydroxide (KOH) in water, mix and dilute to 100
mL.
8.16 Silicic Acid.
8.17 Sodium Chloride (NaCl), heat-treated in a shallow tray at 450°C for a minimum of 4 h to remove any potential interfering
organic substances.
8.18 Sodium Hydroxide Solution (240 g/L)—Dissolve 240 g of sodium hydroxide (NaOH) in water, mix and dilute to 1 L.
8.19 Sodium Sulfate, Acidified—Slurry 100 g of the sodium sulfate that has been heat treated in a shallow tray at 450°C for a
minimum of 4 h with sufficient diethyl ether to just cover the solid. Add 0.1 mL of concentrated sulfuric acid (sp gr 1.84) and mix
thoroughly. Remove the ether with vacuum. Ensure that a pH below 4 can be obtained from mixing 1 g of the solid with 5 mL
of water. Store continuously at 130°C.
8.20 Sodium Thiosulfate, anhydrous (Na S O ), reagent grade.
2 2 3
8.21 Standard Solution, Stock (1.00 μg/μL)—Stock standard solutions may be purchased as certified solutions or prepared from
pure standard materials using the following procedure:
8.21.1 Prepare stock standard solutions by weighing approximately 0.0100 g of pure material to three significant figures. Dissolve
the material in MTBE and dilute to volume in a 10-mL volumetric flask. Larger volumes may be prepared at the convenience of
the analyst. If compound purity is certified at 96 % or greater, the weight may be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock standards may be used at any concentration if they are certified
by the manufacturer or by an independent source.
8.21.2 Transfer the stock standard solutions into TFE-fluorocarbonPTFE sealed screw-cap amber vials. Store at room temperature
and protect from light.
8.21.3 Replace stock standard solutions after two months or sooner if comparison with laboratory fortified blanks, or quality
control sample indicates a problem.
8.22 Standard Solution, Internal—Prepare an internal standard solution by accurately weighing approximately 0.0010 g of pure
DBOB. Dissolve the DBOB in MTBE and dilute to volume in a 10-mL volumetric flask. Transfer the internal standard solution
to a TFE-fluorocarbonPTFE sealed screw cap bottle and store at room temperature. Addition of 25 μL of the internal standard
solution to 10 mL of sample extract results in a final internal standard concentration of 0.25 μg/mL. Solution should be replaced
when ongoing quality control in Section 19 indicates a problem. Note that DBOB has been shown to be an effective internal
standard for the test method analytes (4), but other compounds may be used if the quality control requirements in Section 19 are
met.
8.23 Surrogate Standard Solution—Prepare a surrogate standard solution by weighing approximately 0.0010 g of pure DCAA to
three significant figures. Dissolve the DCAA in MTBE and dilute to volume in a 10-mL volumetric flask. Transfer the surrogate
standard solution to a TFE-fluorocarbonPTFE sealed screw cap bottle and store at room temperature. Addition of 50 μL of the
surrogate standard solution to a 1-L sample prior to extraction results in a surrogate standard concentration in the sample of 5 μg/L
and, assuming quantitative recovery of DCAA, a surrogate standard concentration in the final extract of 0.5 μg/mL. Solution should
be replaced when ongoing quality control described in Section 19 indicates a problem.
NOTE 1—DCAA has been shown to be an effective surrogate standard for the method analytes (4), but other compounds may be used if the quality control
requirements in 19.4 are met.
D5317 − 20
8.24 Sulfuric Acid Solution (335 + 665)—Carefully add, with constant mixing, 335 mL of concentrated sulfuric acid to 665 mL
of water.
8.25 Toluene, pesticide quality.
8.26 Hydrochloric Acid (HCl) (1 + 9)—Carefully add, with constant mixing, 100 mL of concentrated HCl to 900 mL of water.
9. Hazards
9.1 The toxicity or carcinogenicity of each reagent used in this test method has not been precisely defined; however, each chemical
compound must be treated as a potential health hazard. Accordingly, exposure to these chemicals must be reduced to the lowest
possible level. The laboratory is responsible for maintaining a current awareness file of OSHA regulations regarding the safe
handling of the chemicals specified in this test method. A reference file of material safety data sheets should also be made available
to all personnel involved in the chemical analysis. Additional references to laboratory safety are available and have been identified
(29 CFR 1910) (5, 6) for the information of the analyst.
9.2 Diazomethane—A toxic carcinogen that can explode under certain conditions. The following precautions must be followed:
9.2.1 Use only a well ventilated hood—do not breathe vapors.
9.2.2 Use a safety screen.
9.2.3 Use mechanical pipetting aids.
9.2.4 Do not heat above 90°C—Explosion may result.
9.2.5 Avoid grinding surfaces, ground glass joints, sleeve bearings, glass stirrers—Explosion may result.
9.2.6 Store away from alkali metals—Explosion may result.
9.2.7 Solutions of diazomethane decompose rapidly in the presence of solid materials such as copper powder, calcium chloride,
and boiling chips.
9.2.8 The diazomethane generation apparatus used in the esterification procedures 13.2 produces micromolar amounts of
diazomethane to minimize safety hazards.
9.3 Ethyl ether,Ether, pesticide quality, redistilled in glass, if necessary.
9.3.1 Ethyl ether is an extremely flammable solvent. If a mechanical device is used for sample extraction, the device should be
equipped with an explosion-proof motor and placed in a hood to avoid possible damage and injury due to an explosion.
9.3.2 Must be free of peroxides as indicated by test strips. (Warning—When a solvent is purified, stabilizers added by the
manufacturer are removed, thus potentially making the solvent hazardous.)
10. Sample Collection, Preservation, and Storage
10.1 Collect the sample in accordance with Practices D3370 in an amber glass bottle. Do not prerinse the bottle with sample before
collection.
10.2 Add mercuric chloride to the sample bottle in an amount to produce a concentration of 10 mg HgCl by adding 1 mL of a
10 mg HgCl/mL solution to the sample bottle at the sampling site, or in the laboratory before shipping to the sampling site.
(Warning—Mercuric chloride is highly toxic. If the use of another bacteriacide can be shown to be equivalent to HgCl , it can
be used provided all quality control criteria in Sections 18 and 19 are met.)
D5317 − 20
10.3 Test for the presence of chlorine with potassium iodide-starch test paper previously moistened with dilute acid. Darkening
of the test paper indicates the presence of chlorine (and a few other oxidizing materials). Add 80 mg Na S O to the bottle before
2 2 3
adding the sample.
10.4 After the sample is collected in the bottle containing preservative, seal the bottle and shake vigorously for 1 min.
10.5 Immediately store the sample at 4°C away from light until extraction. Preservation study results indicate that the analytes
(measured as total acid) present in samples are stable for 14 days when stored under these conditions (4). However, analyte stability
may be affected by the matrix; therefore, the analyst should verify that the preservation technique is applicable to the samples under
study.
11. Calibration
11.1 Establish GC operating parameters equivalent to those indicated in 7.7. The GC system may be calibrated using either the
internal standard technique (11.2) or the external standard technique (11.3).
NOTE 2—Calibration standard solutions must be prepared such that no unresolved analytes are mixed together.
11.2 Internal Standard Calibration Procedure—Select one or more internal standards compatible in analytical behavior to the
compounds of interest. Demonstrate that the measurement of the internal standard is not affected by test method or matrix
interferences. DBOB has been identified as a suitable internal standard.
11.2.1 Prepare calibration standards at a minimum of three (five are recommended) concentration levels for each analyte of interest
by adding volumes of one or more stock standards to a volumetric flask. To each calibration standard, add a known constant amount
of one or more of the internal standards and 250-μL methanol, and dilute to volume with MTBE. Esterify acids with diazomethane
as described in 13.2 or 13.3. The lowest standard should represent analyte concentrations near, but above, the respective estimated
detection levels (EDLs). The remaining standards should bracket the analyte concentrations expected in the sample extracts, or
should define the working range of the detector (Table 1).
11.2.2 Analyze each calibration standard according to the procedure (Section 16). Tabulate response (peak height or area) against
concentration for each compound and internal standard. Calculate the response factor (RF) for each analyte and surrogate using
the following equation:
A C
~ ! ~ !
s is
RF 5 (1)
A C
~ ! ~ !
is s
where:
A = response for the analyte to be measured,
s
A = response for the internal standard,
is
C = concentration of the internal standard, μg/L, and
is
C = concentration of the analyte to be measured, μg/L.
s
~A ! ~C !
s is
RF 5 (1)
A C
~ ! ~ !
is s
where:
A = response for the analyte to be measured,
s
A = response for the internal standard,
is
C = concentration of the internal standard, μg/L, and
is
C = concentration of the analyte to be measured, μg/L.
s
11.2.3 If the RF value over the working range is constant (20 % RSD or less) use the average RF for calculations. Alternatively,
use the results to plot a calibration curve of response ratios (A /A ) versus C .
s is s
11.2.4 Verify the working calibration curve or RF on each working shift by the measurement of one or more calibration standards.
D5317 − 20
If the response for any analyte varies from the predicted response by more than 620 %, repeat the test using a fresh calibration
standard. If the repetition also fails, generate a new calibration curve for that analyte using freshly prepared standards.
11.2.5 Single-point calibration is a viable alternative to a calibration curve. Prepare single point standards from the secondary
dilution standards in MTBE. Prepare the single point standards at a concentration that produces a response that deviates from the
sample extract response by no more than 20 %.
11.2.6 Verify calibration standards periodically, at least quarterly is recommended, by analyzing a standard prepared from
reference material obtained from an independent source. Results from these analyses must be within the limits used to routinely
check calibration.
11.3 External Standard Calibration Procedure:
11.3.1 Prepare calibration standards at a minimum of three (five are recommended) concentration levels for each analyte of interest
and surrogate compound by adding volumes of one or more stock standards and 250-μL methanol to a volumetric flask. Dilute to
volume with MTBE. Esterify acids with diazomethane (13.2 or 13.3). The lowest standard should represent analyte concentrations
near, but above, the respective EDL (Table 1). The remaining standards should bracket the analyte concentrations expected in the
sample extracts, or should define the working range of the detector.
11.3.2 Starting with the standard of lowest concentration, analyze each calibration standard according to Section 16 and tabulate
response (peak height or area) versus the concentration curve for each compound. Alternatively, if the ratio of response to
concentration (calibration factor) is a constant over the working range (20 % RSD or less), assume linearity through the origin and
put the average ratio or calibration factor in place of a calibration curve.
11.3.3 Verify the working calibration curve or calibration factor on each working day by the measurement of a minimum of two
calibration check standards, one at the beginning and one at the end of the analysis day. These check standards should be at two
different concentration levels to verify the calibration curve. For extended periods of analysis (greater than 8 h), it is strongly
recommended that check standards be interspersed with samples at regular intervals during the course of the analyses. If the
response is by more than 620 %, repeat the test using a fresh calibration standard. If the results still do not agree, generate a new
calibration curve or use a single-point calibration standard as described in 11.3.4.
11.3.4 Single-point calibration is a viable alternative to calibration curve. Prepare single-point standards from the secondary
dilution standards in MTBE. Prepare the single-point standards at a concentration that produces a response that deviates from the
sample extract response by no more than 20 %.
11.3.5 Verify calibration standards periodically, recommend at least quarterly, by analyzing a standard prepared from reference
material obtained from an independent source. Results from these analyses must be within the limits used to routinely check
calibration.
12. Procedure
12.1 Manual Hydrolysis, Preparation, and Extraction:
12.1.1 Add preservative to every blank sample and quality-control check the standard. Mark the water meniscus on the side of
the sample bottle for later determination of sample volume (12.1.9). Pour the entire sample into a 2-L separatory funnel. Fortify
sample with 50 μL of the surrogate standard solution.
12.1.2 Add 250 g NaCl to the sample, seal, and shake to dissolve salt.
12.1.3 Add 17 mL of NaOH solution (240 g/L) to the sample, seal, and shake. Check the pH of the sample with pH paper; if the
sample does not have a pH greater than or equal to 12, adjust the pH by adding more NaOH (240 g/L). Let the sample sit at room
temperature for 1 h, and shake the separatory funnel and contents periodically.
12.1.4 Add 60-mL methylene chloride to the sample bottle to rinse the bottle. Transfer the methylene chloride to the separatory
funnel and extract the sample by vigorously shaking the funnel for 2 min with periodic venting to release excess pressure. Allow
the organic layer to separate from the water phase for a minimum of 10 min. If the emulsion interface between layers is more than
one-third the volume of the solvent layer, the analyst must employ mechanical techniques to complete the phase separation. The
D5317 − 20
optimum technique depends upon the sample, but may include stirring, filtration through glass wool, centrifugation, or other
physical methods. Discard the methylene chloride phase.
12.1.5 Add a second 60 mL volume of methylene chloride to the sample bottle and repeat the extraction procedure a second time,
discarding the methylene chloride layer. Perform a third extraction in the same manner.
12.1.6 Add 17 mL of H SO solution (335 + 665) to the sample, seal, and shake to mix. Check the pH of the sample with pH
2 4
paper; if the sample does not have a pH less than or equal to 2, adjust the pH by adding more H SO solution (335 + 665).
2 4
12.1.7 Add 120-mL ethyl ether to the sample, seal, and extract the sample by vigorously shaking the funnel for 2 min with periodic
venting to release excess pressure. Allow the organic layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one third the volume of the solvent layer, the analyst must employ mechanical
techniques to complete the phase separation. The optimum technique depends upon the sample, but may include stirring, filtration
through glass wool, centrifugation, or other physical methods. Remove the aqueous phase to a 2-L Erlenmeyer flask and collect
the ethyl ether phase in either a 500-mL round-bottom flask or a 500-mL Erlenmeyer flask containing approximately 10 g of
acidified anydrous sodium sulfate. Periodically, vigorously shake the sample and drying agent. Allow the extract to remain in
contact with the sodium sulfate for approximately 2 h.
12.1.8 Return the aqueous phase to the separatory funnel, add a 60-mL volume of ethyl ether to the sample, and repeat the
extraction procedure a second time, combining the extracts in the 500-mL round-bottom or Erlenmeyer flask. Perform a third
extraction with 60 mL of ethyl ether in the same manner.
12.1.9 Determine the original sample volume by refilling the sample bottle to the mark and transferring the water to a 1000-mL
graduated cylinder. Record the sample volume to the nearest 5 mL.
D5317 − 20
12.2 Automated Hydrolysis, Preparation, and Extraction:
12.2.1 Follow the fortification and preservation procedures given in 12.1.1. If the mechanical separatory funnel shaker is used,
pour the entire sample into a 2-L separatory funnel. If the mechanical tumbler is used, pour the entire sample into a tumbler bottle.
12.2.2 Add 250 g of NaCl to the sample, seal, and shake to dissolve salt.
12.2.3 Add 17 mL of NaOH solution (240 g/L) to the sample, seal, and shake. Check the pH of the sample with pH paper; if the
sample does not have a pH greater than or equal to 12, adjust the pH by adding more NaOH (240 g/L). Shake sample for 1 h using
the appropriate mechanical mixing device.
12.2.4 Add 300 mL methylene chloride to the sample bottle to rinse the bottle, transfer the methylene chloride to the separatory
funnel or tumbler bottle, seal, and shake for 10 s, venting periodically. Repeat shaking and venting until pressure release is not
observed during venting. Reseal and place sample container in appropriate mechanical mixing device. Shake or tumble the sample
for 1 h. Complete and thorough mixing of the organic and aqueous phases should be observed at least 2 min after starting the
mixing device.
12.2.5 Remove the sample container from the mixing device. If the tumbler is used, pour contents of tumbler bottle into a 2-L
separatory funnel. Allow the organic layer to separate from the water phase for a minimum of 10 min. If the emulsion interface
between layers is more than one third the volume of the solvent layer, the analyst must employ mechanical techniques to complete
the phase separation. The optimum technique depends upon the sample, but may include stirring, filtration through glass wool,
centrifugation, or other physical methods. Drain and discard the organic phase. If the tumbler is used, return the aqueous phase
to the tumbler bottle.
12.2.6 Add 17 mL of H SO solution (335 + 665) to the sample, seal, and shake to mix. Check the pH of the sample with pH
2 4
paper; if the sample does not have a pH less than or equal to 2, adjust the pH by adding more H SO solution (335 + 665).
2 4
12.2.7 Add 300-mL ethyl ether to the sample, seal, and shake for 10 s, venting periodically. Repeat shaking and venting until
pressure release is not observed during venting. Reseal and place sample container in appropriate mechanical mixing device. Shake
or tumble sample for 1 h. Complete and thorough mixing of the organic and aqueous phases should be observed at least 2 min
after starting the mixing device.
12.2.8 Remove the sample container from the mixing device. If the tumbler is used, pour contents of tumbler bottle into a 2-L
separatory funnel. Allow the organic layer to separate from the water phase for a minimum of 10 min. If the emulsion interface
between layers is more than one third the volume of the solvent layer, the analyst must employ mechanical techniques to complete
the phase separation. The optimum technique depends upon the sample, but may include stirring, filtration through glass wool,
centrifugation, or other physical methods. Drain and discard the aqueous phase. Collect the extract in a 500-mL Erlenmeyer or
round-bottom flask containing about 10 g of acidified anhydrous sodium sulfate. Periodically, vigorously shake the sample and
drying agent. Allow the extract to remain in contact with the sodium sulfate for approximately 2 h.
12.2.9 Determine the original sample volume by refilling the sample bottle to the mark and transferring the water to a 1000-mL
graduated cylinder. Record the sample volume to the nearest 5 mL.
12.3 Extract Concentration:
12.3.1 Assemble a K-D Concentrator by attaching a concentrator tube to a 500-mL evaporative flask.
12.3.2 Pour the dried extract through a funnel plugged with acid-washed glass wool, and collect the extract in the K-D
concentrator. Use a glass rod to crush any caked sodium sulfate during the transfer. Rinse the flask and funnel with 20 to 30 mL
of ethyl ether to complete the quantitative transfer.
12.3.3 Add 1 to 2 clean boiling stones to the evaporative flask and attach a macro-Snyder column. Prewet the Snyder column by
adding about 1 mL ethyl ether to the top. Place the K-D apparatus on a hot water bath, 60 to 65°C, so that the concentrator tube
is partially immersed in the hot water, and the entire lower rounded surface of the flask is bathed with hot vapor. At the proper
rate of the distillation the balls of the column will actively chatter, but the chambers will not flood. When the apparent volume of
liquid reaches 1 mL, remove the K-D apparatus and allow it to drain and cool for at least 10 min.
D5317 − 20
12.3.4 Remove the Snyder column and rinse the flask and its lower joint into the concentrator tube with 1 to 2 mL of ethyl ether.
Add 2 mL of MTBE and a fresh boiling stone. Attach a micro–Snyder column to the concentration tube and prewet the column
by adding about 0.5 mL of ethyl ether to the top. Place the micro K-D apparatus on the water bath so that the concentrator tube
is partially immersed in the hot water. Adjust the vertical position of the apparatus and the water temperature as required to
complete concentration in 5 to 10 min. When the apparent volume of liquid reaches 0.5 mL, remove the micro K-D from the bath
and allow it to drain and cool. If the gaseous diazomethane procedure (13.2) is to be used for esterification, rinse the walls of the
concentrator tube while adjusting the volume to 5.0 mL with MTBE. If diazomethane solution is to be used (13.3) rinse the walls
of the concentrator tube while adjusting the volume to 4.5 mL with MTBE.
13. Esterification
13.1 Two methods are described for using deazomethanediazomethane as the esterifications reagent.
13.2 Gaseous Diazomethane Procedure:
13.2.1 Assemble the diazomethane generator (Fig. 1) in a hood.
13.2.2 Add 5 mL of ethyl ether to Tube 1. Add 1 mL of ethyl ether, 1 mL of carbitol, 1.5 mL of aqueous KOH solution (37 g/100
mL), and 0.2 g N-methyl-N-nitroso-paratoluenesulfonamide to Tube 2. Immediately place the exit tube into the concentrator tube
containing the sample extract. Apply nitrogen flow (10 mL/min) to bubble diazomethane through the extract for 1 min. Remove
first sample. Rinse the tip of the diazomethane generator with ethyl ether after methylation of each sample. Bubble diazomethane
through the second sample extract for 1 min. Diazomethane reaction mixture should be used to esterify only two samples; prepare
new reaction mixture in Tube 2 to esterify each two additional samples. Samples should turn yellow after addition of diazomethane
and remain yellow for at least 2 min. The presence of color or particulates can obscure the yellow color in some samples. Evolution
of N gas in 13.3.5 will indicate that sufficient diazomethane was present to complete the reaction. Repeat methylation procedure
if necessary.
13.2.3 Seal concentrator tubes with stoppers. Store at room temperature in a hood for 30 min.
13.2.4 Destroy any unreacted diazomethane by adding 0.1 to 0.2 g silicic acid to the concentrator tubes. Allow to stand until th
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