ASTM D7065-17

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: D7065 − 11 D7065 − 17
Standard Test Method for
Determination of Nonylphenol, Bisphenol A, p-tert-
Octylphenol, Nonylphenol Monoethoxylate and Nonylphenol
Diethoxylate in Environmental Waters by Gas
Chromatography Mass Spectrometry
This standard is issued under the fixed designation D7065; 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 determination of nonylphenol (NP), nonylphenol ethoxylate (NP1EO), nonylphenol diethoxylate
(NP2EO), octylphenol (OP), and bisphenol A (BPA) that are partitioned into organic solvent, separated using gas chromatography
and detected with mass selective detection. These compounds or isomer mixtures are qualitatively and quantitatively determined
by this test method. This test method adheres to selected ion monitoring mass spectrometry but full scan mass spectrometry has
also been shown to work well under these conditions. Either analysis may be used.
1.2 The method detection limit (MDL) and reporting limit (RL) for NP, NP1EO, NP2EO, OP, and BPA are listed in Table 1.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 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 safety, health, and healthenvironmental practices and to determine the
applicability of regulatory limitations prior to use.
1.5 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
D3694 Practices for Preparation of Sample Containers and for Preservation of Organic Constituents
D3856 Guide for Management Systems in Laboratories Engaged in Analysis of Water
D5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis
D5905 Practice for the Preparation of Substitute Wastewater
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
2.2 Other Publications:
40 CFR Part 136, Appendix B Definition and Procedure for the Determination of the Method Detection Limit
3. Terminology
3.1 Definitions:
3.1.1 For definitions of terms used in this standard, refer to Terminology D1129.
3.2 Definitions:Definitions of Terms Specific to This Standard:
3.1.1 Nonylphenol, NP, n—nonylphenol is mixed isomers of branched p-nonylphenol.
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 June 15, 2011Dec. 15, 2017. Published July 2011January 2018. Originally published in 2006. Last previous version approved in 20062011 as
D7065 – 06.11. DOI: 10.1520/D7065-11.10.1520/D7065-17.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from U.S. Government Printing Office, Superintendent of Documents, 732 N. Capitol St., NW, Washington, DC 20401-0001, http://www.access.gpo.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7065 − 17
TABLE 1 MDL and Reporting Limits
3.1.1.1 Discussion—
A B
MDL Reporting Range
Analyte
, (μg/L) (μg/L)
NP 0.9 5.0-80.0
NP1EO 1.2 10.0-160.0
NP2EO 1.8 20.0-320.0
OP 0.2 1.0-16.0
BPA 0.3 1.0-16.0
TABLE 1 Method Detection Limit (MDL) and Reporting Limits
A B
MDL, Reporting Range,
Analyte
(μg/L) (μg/L)
NP 0.9 5.0–80.0
NP1EO 1.2 10.0–160.0
NP2EO 1.8 20.0–320.0
OP 0.2 1.0–16.0
BPA 0.3 1.0–16.0
A
MDL Determined Following Thedetermined following the Code of Federal
Regulations, 40 CFR Part 136, Appendix B.
B
Lowest Pointpoint of the Reporting Rangereporting range is Calculatedcalcu-
lated from the LV1 Concentration Calibration Standardconcentration calibration
standard in Table 4.
Commercial nonylphenol is produced by the reaction of phenol with commercial nonene. Commercial nonene is not simply a linear
C H alpha olefin; it is a complex mixture of predominantly nine-carbon olefins, called propylene trimer, containing no linear
9 18
isomers. This synthesis results in a mixture of various branched nonylphenol isomers rather than a discrete chemical structure. The
branched nonyl group is positioned predominantly in the para position on the phenol ring.
3.2.1 bisphenol A, BPA, n—represents 4,4’-dihydroxy-2,2-diphenylpropane.
3.2.1.1 Discussion—
Commercial bisphenol A is produced by the condensation reaction of phenol and acetone to produce predominantly the
4,4’-dihydroxy-2,2-diphenylpropane.
3.1.2 Octylphenol, OP, n—OP represents 4-(1,1,3,3-tetramethylbutyl)phenol.
3.1.2.1 Discussion—
Commercial octylphenol is produced by the reaction of phenol and diisobutylene to produce predominantly the 4-(1,1,3,3-
tetramethylbutyl)phenol isomer.
3.2.2 environmental water, n—shall refer to water tested using this test method. See Section 5.
3.1.3 Bisphenol A, BPA, n-BPA represents 4,4’-dihydroxy-2,2-diphenylpropane.
3.1.3.1 Discussion—
Commercial bisphenol A is produced by the condensation reaction of phenol and acetone to produce predominantly the
4,4’-dihydroxy-2,2-diphenylpropane.
3.2.3 nonylphenol, NP, n—mixed isomers of branched p-nonylphenol.
3.2.3.1 Discussion—
Commercial nonylphenol is produced by the reaction of phenol with commercial nonene. Commercial nonene is not simply a linear
C H alpha olefin; it is a complex mixture of predominantly nine-carbon olefins, called propylene trimer, containing no linear
9 18
isomers. This synthesis results in a mixture of various branched nonylphenol isomers rather than a discrete chemical structure. The
branched nonyl group is positioned predominantly in the para position on the phenol ring.
3.1.4 Environmental water, n—it shall refer to water tested using this method. See Section 5.
3.2.4 octylphenol, OP, n—represents 4-(1,1,3,3-tetramethylbutyl)phenol.
3.2.4.1 Discussion—
D7065 − 17
Commercial octylphenol is produced by the reaction of phenol and diisobutylene to produce predominantly the 4-(1,1,3,3-
tetramethylbutyl)phenol isomer.
3.3 Abbreviations:
3.2.1 NP1EO—branched nonylphenol monoethoxylate.
3.3.1 n-NP—normal straight chain nonylphenol
3.3.1.1 Discussion—
n-NP is used in this test method as a surrogate for NP, OP and BPA. n-NP is not produced commercially and is not expected to
be found in environmental waters.
3.2.2 NP2EO—branched nonylphenol diethoxylate.
3.3.2 n-NP1EO—normal straight chain nonylphenol ethoxylate
3.3.2.1 Discussion—
n-NP1EO is used in this test method as a surrogate for NP1EO and NP2EO. n-NP1EO is not produced commercially and is not
expected to be found in environmental waters.
3.2.3 n-NP—normal straight chain nonylphenol.
3.2.3.1 Discussion—
n-NP is used in this method as a surrogate for NP, OP and BPA. n-NP is not produced commercially and is not expected to be found
in environmental waters.
3.3.3 NP1EO—branched nonylphenol monoethoxylate
3.2.4 n-NP1EO—normal straight chain nonylphenol ethoxylate.
3.2.4.1 Discussion—
n-NP1EO is used in this method as a surrogate for NP1EO and NP2EO. n-NP1EO is not produced commercially and is not
expected to be found in environmental waters.
3.3.4 NP2EO—branched nonylphenol diethoxylate
4. Summary of Test Method
4.1 This is a performance-based test method and modifications are allowed to improve performance.
4.2 For NP, NP1EO, NP2EO, BPA, and OP analysis, continuous liquid-liquid extraction technique is used for water samples.
4.3 Continuous Liquid-Liquid Extraction Technique—A 1-L volume of sample adjusted to pH 2 is extracted with methylene
chloride. The methylene chloride extract is dried using sodium sulfate if needed, concentrated to a volume of 0.5 mL, and then
analyzed by GC/MS operated in the selected ion monitoring (SIM) or full scan mode.
4.4 The target compounds are identified by retention time and confirmed by comparing the sample mass spectrum to that of a
known standard. The target compounds are quantitated using the quantitation ions of the target compounds utilizing the internal
standards acenaphthene-d , and phenanthrene-d . The final report issued for each sample lists total concentration of NP, NP1EO,
10 10
NP2EO, BPA, and OP, if detected, or MDLs, if not detected, in μg/L for water samples.
5. Significance and Use
5.1 Nonylphenol, , octylphenol, and bisphenol A have been shown to have toxic effects in aquatic organisms. The source of
nonylphenol and octylphenol is prominently from the use of common commercial surfactants. The most widely used surfactant is
NPEO which has an average ethoxylate chain of 9 mol of ethoxylate. The ethoxylate chain is readily biodegraded to form NP1EO
and NP2EO, nonylphenol carboxylate (NPEC) and, under anaerobic conditions, nonylphenol. Nonylphenol will also biodegrade,
but may be released into environmental waters directly at trace levels. This test method has been investigated for use with surface
water and waste treatment effluent samples and is applicable to these matrices. It has not been investigated for use with salt water
or solid sample matrices.
Aquatic Life Ambient Water Quality Criteria- Nonylphenol Final, US EPA Office of Water Document Number EPA-822-R-05-005, December 2005. You can request a
copy by sending an email (center.water-resource@epa.gov) or by conventional mail to EPA Water Resource Center, 4101T, 1200 Pennsylvania Avenue, N.W., Washington,
DC 20460.U.S. EPA Office of Water, Aquatic Life Ambient Water Quality Criteria — Nonylphenol Final, Document Number EPA-822-R-05-005, December 2005. Available
from United States Environmental Protection Agency (EPA), William Jefferson Clinton Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20460, http://www.epa.gov.
D7065 − 17
5.2 The first reported synthesis of BPA was by the reaction of phenol with acetone by Zincke. BPA has become an important
high volume industrial chemical used in the manufacture of polycarbonate plastics and epoxy resins. Polycarbonate plastic and
resins are used in numerous products including electrical and electronic equipment, automobiles, sports and safety equipment,
reusable food and drink containers, electrical laminates for printed circuit boards, composites, paints, adhesives, dental sealants,
protective coatings, and many other products. The environmental source of BPA is predominantly from the decomposition of
polycarbonate plastics and resins. BPA is not classified as bio-accumulative by the U.S. Environmental Protection Agency (EPA)
and will biodegrade. BPA may be released into the environment waters directly at trace levels through landfill leachate and sewage
treatment plant effluents.
6. Interferences
6.1 Method interferences may be caused by contaminants in solvents, reagents, glassware and other apparatus that lead to
discrete artifacts or elevated baseline in the selected ion current profiles. All of these materials are routinely demonstrated to be
free from interferences by analyzing laboratory reagent blanks under the same conditions as the samples.
6.2 All glassware is scrupulously cleaned. All glassware is washed in hot water with detergent such as powdered Alconox,
Deto-Jet,Det-o-Jet, Luminox, or Citrojet,Citrajet, rinsed in hot water and rinsed with distilled water. The glassware is then dried
and heated in an oven at 250°C for 15 to 30 min. All glassware is subsequently cleaned with acetone and methylene chloride.
Detergents containing alkylphenolic compounds must not be used.
6.3 All reagents and solvents should be of pesticide residue purity or higher to minimize interference problems.
6.4 Matrix interferences may be caused by contaminants that are co-extracted from the sample. The extent of matrix
interferences will vary considerably from sample source to sample source, depending on variations of the sample matrix.
7. Apparatus
7.1 GC/MS System:
7.1.1 Gas Chromatograph (GC) System—An analytical system complete with a temperature programmable gas chromatograph
and all required accessories including syringes, analytical columns, autosamplers, and gases. The injection port must be designed
for split/splitless when using the capillary columns.
7.1.2 Analytical Column—An analytical column (DB-5MS 30-m × 0.25 mm i.d;ID; film thickness—0.25 μm or equivalent;
(5 %-phenyl)-methylpolysiloxane) suitable for the analysis of target alkylphenols.
7.1.3 Mass Spectrometer (MS) System—An MS system capable of scanning 45 to 500 amu every 2 s or less, using 70 eV in the
electron impact mode, and producing a mass spectrum which meets all the criteria when 50 ng of decafluorotriphenylphosphine
(DFTPP) is injected through the GC inlet.
7.2 CLLE Apparatus.
7.3 Organic Solvent Evaporation Device.
8. Reagents and Materials
8.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless indicated otherwise, it is intended that all
reagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society. Other
reagent grades may be used provided it is first ascertained that they are of sufficiently high purity to permit their use without
affecting the accuracy of the measurement.
8.2 Purity of Water—Unless otherwise indicated, references to water shall be understood to mean reagent water conforming to
Type I of specificationSpecification D1193. It must be demonstrated that this water does not contain contaminants at concentrations
sufficient to interfere with the analysis.
8.3 Gases—Research grade nitrogen or helium of highest purity are used.
8.4 Methylene Chloride, chromatography grade.
8.5 Methanol, purge and trap grade.
Zincke, T., 1905, “Mittheilungen aus dem chemischen Laboratorium der Universitat Marburg,” Justus Leibigs Annals Chemie, Vol. 343, pages 75-79.Zincke, T., 1905,
“Mittheilungen aus dem chemischen Laboratorium der Universitat Marburg,” Justus Leibigs Annals Chemie, Vol 343, pp. 75–79.
Additional information about BPA is available on the internet at http://www.bisphenol-a.orgat http://www.bisphenol-a.org.
Alconox, Det-o-Jet, Luminox, and Citrajet are trademarks of Alconox, Inc., White Plains, NY.
The sole source of supply of the columns known to the committee at this time is J&W Columns, Agilent Technologies, Inc., 2850 Centerville Rd., Wilmington, DE 19808.
If you are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting
of the responsible technical committee, which you may attend.
Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed by
the American Chemical Society, see Annual 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.
D7065 − 17
8.6 Branched Nonylphenol Monoethoxylate (NP1EO),available as a high purity custom standard.
8.7 Branched Nonylphenol Diethoxylate (NP2EO),available as a high purity custom standard.
8.8 Branched Nonylphenol Ethoxylate Blend (NP1EO–NP3EO),where the composition is determined by gas chromatography.
8.9 Nonylphenol (NP),>95 % para isomer (CAS #84852-15-3).# 84852-15-3).
8.10 Octylphenol (OP),99+ % 4-(1,1,3,3-tetramethylbutyl)phenol (CAS #140-66-9).# 140-66-9).
8.11 Bisphenol A (BPA),99+ % 4,4'-ispropylidenediphenol (CAS #80-05-7).# 80-05-7).
8.12 Concentrated H SO (CAS #7664-93-9).(CAS # 7664-93-9)
2 4
8.13 Internal Standard Mix, containing acenaphthene-d and phenanthrene-d .
10 10
8.14 n-nonylphenol (CAS #104-40-5).(CAS # 104-40-5).
8.15 n-NP monoethoxylate (n-NP1EO, CAS #104-35-8).(n-NP1EO, CAS # 104-35-8).
8.16 Acetone, Reagent Grade (CAS # 67-64-1).(CAS # 67-64-1).
8.17 Perfluorotributylamine, PFTBA Perfluorotributylamine,(CAS PFTBA, (CAS# # 311-89-7).
9. Hazards
9.1 Normal laboratory safety applies to this test method. Analysts should wear safety glasses, gloves and lab coats when
working with acids. Methylene chloride is used as an extraction solvent for this test method. Analysts should review the MSDS
for all reagents used in this test method.
10. Sample Collection, Preservation, and Storage
10.1 Sampling:
10.1.1 Grab samples must be collected in glass sample containers. Conventional sampling practices should be followed. Refer
to Guide D3856 and PracticePractices D3694. Automatic sampling equipment should be as free as possible of Tygon tubing and
other potential sources of contamination. Samples must be iced or kept at 0 to 4ºC. Samples must be prevented from freezing.
10.2 Preservation:
10.2.1 Adjust to pH 2 with H SO . Store samples between 0 and 4ºC from the time of collection until extraction. Extract the
2 4
sample within 28 days of collection and completely analyze within 40 days of extraction.
10.2.2 Sample extracts may be stored in sealed glass containers at <0°C indefinitely.
11. Preparation of GC/MS
11.1 Chromatograph Operating Conditions (approximate values, your instrument may require different settings):
Carrier Gas: Helium
Carrier Flow: Variable (1.3 to 0.4 mL/min),
Constant Pressure
(11.16 psi approximately)
Average Velocity 42 cm/s
Injection Port Parameters: Splitless Injection
Injection Pressure: 10 to 12 psi
Injection port temperature: 290°C
Injection Port Temperature: 290°C
Purge flow to split vent: 30mL/min at 0.75 min,
Purge Flow to Split Vent: 30mL/min at 0.75 min,
Total Flow 34.2 mL/min
Column oven temperature: 50°C initially and hold 2 min
Column Oven Temperature: 50°C initially and hold 2 min
50 to 320°C at 10°C/min
320°C – hold 5 min
Injection Volume: 1 μL
Injection Liner: Single taper liner
MS Transfer Line Temperature: 290°C
11.2 Mass Spectrometer Parameters:
The sole source of supply of the blend known to the committee at this time is Schenectady International, Inc., 2750 Balltown Road, Schenectady, NY 12309. If you
are aware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of
the responsible technical committee, which you may attend.
D7065 − 17
Mode: Electron Ionization
Electron Multiplier: Set electron multiplier to achieve
optimal performance.
Tune: Autotune using PFTBA masses 69,
219, and 502.
Dwell Time: 30 ms
SIM Ions: Refer to Table 2.
NOTE 1—For details regarding retention times and quantitation ions refer to Table 2.
12. Calibration and Standardization
12.1 In order to be certain that analytical values obtained using this test method are valid and accurate within the confidence
limits of the test, the following procedures must be followed when performing thethis test method.
12.2 Calibration and Standardization:
12.2.1 To calibrate the instrument, analyze 5 calibration standards containing 5 increasing concentration levels of NP, NP1EO,
NP2EO, BPA, OP, n-NP, and n-NP1EO prior to analysis of sample. The values in Table 3 are shown as approximate concentrations.
A calibration stock standard solution is prepared from standard materials or purchased as certified solutions. Stock standard
solutionSolution A (Level 5) containing NP, NP1EO, NP2EO, BPA, OP, n-NP, and n-NP1EO is prepared at Level 5 concentration
and aliquots of that solution are diluted to prepare Levels 1 through 4. There are many ways to accomplish this; the following steps
A
TABLE 2 Retention Time (RT) and Electron Impact Ions.Ions
RT Quantitation
Parameter Confirmation Ions
(Minutes) Ions
Octylphenol 16.50 135 107, 91
Nonylphenol (NP) 17.58 121 107, 163, 220
Isomer Group 1
Nonylphenol (NP) 17.58 121 107, 163, 220
Isomer Group 1
NP Isomer Group 2 17.71 135 107, 121, 220
NP Isomer Group 3 17.80 149 135, 107, 220
NP Isomer Group 4 17.87 149 121, 220
NP Isomer Group 5 17.90 135 121, 107, 220
NP Isomer Group 6 17.94 149 121, 107, 220
NP Isomer Group 7 18.05 135 107, 163, 220
NP Isomer Group 8 18.16 149 121, 107, 220
NP Isomer Group 9 18.18 163 121, 107, 220
NP Isomer Group 10 18.28 135 107, 149, 220
NP Isomer Group 11 18.37 149 107, 121, 220
NP Isomer Group 12 18.39 135 149, 107, 220
NP1EO Isomer Group 1 20.45 165 207, 221, 264
NP1EO Isomer Group 2 20.58 179 135, 107, 264
NP1EO Isomer Group 3 20.66 179 193, 107, 264
NP1EO Isomer Group 4 20.71 179 193, 165, 264
NP1EO Isomer Group 5 20.78 179 193, 165, 264
NP1EO Isomer Group 6 20.91 179 207, 135, 264
NP1EO Isomer Group 7 20.97 193 179, 221, 264
NP1EO Isomer Group 8 21.05 207 165, 107, 264
NP1EO Isomer Group 9 21.12 179 135, 193, 264
NP1EO Isomer Group 10 21.22 193 179, 107, 264
Bisphenol A 22.82 213 228, 119
NP2EO Isomer Group 1 23.29 251 265, 209, 308
NP2EO Isomer Group 2 23.44 223 135, 308
NP2EO Isomer Group 3 23.49 237 223, 279, 308
NP2EO Isomer Group 4 23.53 223 135, 237, 308
NP2EO Isomer Group 5 23.59 223 135, 237, 308
NP2EO Isomer Group 6 23.63 237 209, 279, 308
NP2EO Isomer Group 7 23.78 237 223, 265, 308
NP2EO Isomer Group 8 23.84 251 237, 223, 308
NP2EO Isomer Group 9 23.92 223 135, 308
NP2EO Isomer Group 10 24.03 237 223, 149, 308
n-NP (Surrogate) 19.63 107 135, 220
n-NP1EO (Surrogate) 22.47 107 151, 264, 91
Acenaphthene-d 15.04 164 140
(Internal Std.)
Acenaphthene-d 15.04 164 140
(Internal Std.)
Phenanthrene-d 18.86 188 94, 160
(Internal Std.)
Phenanthrene-d 18.86 188 94, 160
(Internal Std.)
A
Refer to Figs. 1-5, which will make the quantitation method more apparent.
D7065 − 17
TABLE 3 Concentrations of Calibration Standards (ng/μL)
LV 1 LV 2 LV 3 LV 4 LV 5
MSP/Surrogate
(ng/μL) (ng/μL) (ng/μL) (ng/μL) (ng/μL)
NP 10 20 40 80 160
NP1EO 20 40 80 160 320
NP2EO 40 80 160 320 640
Bisphenol A 2 4 8 16 32
Octylphenol 2 4 8 16 32
n-NP 2 4 8 16 32
n-NP1EO 2 4 8 16 32
Internal Standards 25 25 25 25 25
in this section will produce standards with the concentrations values shown in Table 3. The analyst is responsible for recording
initial component weights carefully when working with the pure materials, and carrying the weights through the dilution
calculations correctly.
12.2.2 Prepare stock standard Solution A (Level 5) by adding to a 10 mL volumetric flask solutions of the following: 20 μL of
NP (80 000 μg/mL), 20 μL of NP1EO (160 000 μg ⁄mL), 20 μL of NP2EO (320 000 μg/mL), 8 μL of octylphenol (40 000 μg/mL),
8 μL of bisphenol A (40 000 μg ⁄mL), 32 μL of n-NP (10 000 μg/mL), 32 μL of n-NP1EO (10 000 μg ⁄mL) then dilute to 10 mL
with methylene chloride. The preparation of the Level 5 standard can be accomplished using different volumes and concentrations
of stock solutions as is accustomed in the individual laboratory.
12.2.3 Aliquots of Solution A are then diluted with methylene chloride to prepare the desired calibration level. A 0.50-mL
aliquot of each diluted standard is transferred to a 2-mL crimp-top GC autosampler vial and 6.25 μL of a 2000 ng/μL Internal
Standard solution (12.9) is added. The vials are stored in the freezer at 0ºC or less and protected from light. Calibration standards
are routinely replaced every six months if not previously discarded for QC quality control (QC) criteria failure.
12.2.4 Inject each standard and obtain a chromatogram for each one. The average response factors are calculated as described
in 12.2.6. These values are used to calculate the amount of each individual target compound (OP, BPA) and surrogates n-NP,
n-NP1EO, as well as isomer groups for NP, NP1EO, and NP2EO. The isomer groups that are present, as confirmed by matching
mass spectra, are added to yield the total amount of the compound. NP, NP1EO, and NP2EO are reported as total NP, NP1EO,
and NP2EO, and not as their individual isomers. Calculate the concentration in ppb for each analyte. NP, NP1EO, or NP2EO can
be reported if present at or above their method detection limit as long as their values are accompanied by appropriate qualification
codes. No qualification codes are needed if the values are at or above their respective reporting limits.
12.2.5 Relative Response Factor (RRF) Calculations—Calculate the relative response factor (RRF) for each target and surrogate
compound using Eq 1. The primary characteristic ions used for quantitation are listed in Table 2. Assign the target compounds and
surrogate compound to an internal standard according to Table 4. If an interference prevents the use of a primary ion for a given
internal standard, use a secondary ion listed in Table 2.
NOTE 2—Unless stated otherwise, the area response of the primary characteristic ion is the quantitation ion.
12.2.6 If the RRF value over the working range is a constant (<35 % RSD), the RRF can be assumed to be invariant and the
average response factor (ARF) can be used for calculations. Alternatively, the results can be used to plot a calibration curve of the
response ratios A /A versus concentration ratios C /C .
x is x is
12.2.6.1 Relative Response Factor (RRF):
A C
x is
RRF 5 (1)
A C
is x
where:
A = area of the characteristic ion (EICP) for the compound the be measured (see Table 2),
x
A = area of the characteristic ion (EICP) for the specific internal standard (see Table 2 and Table 4),
is
C = concentration of the internal standard, and
is
C = concentration of the compound to be measured.
x
12.2.6.2 Average Response Factor (ARF)—Average of the relative response factors (RRF) is shown in Eq 2:
TABLE 4 Compounds Quantitated Against Selected Internal
Standards
Internal Standards Acenaphthene-d Phenanthrene-d
10 10
Compounds Octylphenol n-NP
Quantitated
NP n-NP1EO
Bisphenol A
NP1EO
NP2EO
D7065 − 17
n
RRF
( n
i51
Average response factor 5 (2)
n
where:
RRF = relative response factor for each calibration standard, and
n
n = number of calibration standards (5 recommended).
12.2.6.3 Percent Relative Standard Deviation (RSD)—Eq 3 is used to calculate the RSD of the RRF values over the calibration
range:
σ
RSD 5 3100 (3)
x¯
where:
Standard Deviation =
n
xi 2 x¯
Π~ !
(
i51
n 2 1
x = each individual value used to calculate the mean,
i
x¯ = the mean of n value,
n = the total number of values, and
σ = standard deviation.
12.3 Initial Demonstration of Laboratory Capability:
12.3.1 If a laboratory has not performed the test before or if there has been a major change in the measurement system, for
example new analyst, new instrument, etc., a precision and bias study must be performed to demonstrate laboratory capability.
12.3.2 Analyze at least four replicates of a sample solution containing NP, NP1EO, NP2EO, BPA, OP, n-NP, and n-NP1EO at
a concentration near the midpoin
...