ASTM D8018-15(2020)

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: D8018 − 15 (Reapproved 2020)
Standard Test Method for
Determination of (Tri-n-butyl)-n-tetradecylphosphonium
chloride (TTPC) in Soil by Multiple Reaction Monitoring
Liquid Chromatography/Mass Spectrometry (LC/MS/MS)
This standard is issued under the fixed designation D8018; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 20mLin75%acetone/25%water.Thefinalextractvolumeis
20mL because a 15-mL volume of acetone is added to each
1.1 This procedure covers the determination of (Tri-n-
soil sample and only the liquid layer after extraction is filtered
butyl)-n-tetradecylphosphonium chloride (TTPC) in a soil
leaving the solid behind followed by the addition of 5 mL of
matrix by extraction with acetone, filtration, dilution with
water to the acetone extract.
water, and analysis by liquid chromatography/tandem mass
spectrometry.TTPCisabiocidethatstronglyadsorbstosoils. 1.3 Units—The values stated in SI units are to be regarded
Thesampleextractsarepreparedinasolutionof75%acetone asstandard.Nootherunitsofmeasurementareincludedinthis
and 25% water because TTPC has an affinity for surfaces and standard.
particles. The reporting range for this method is from 250 to
1.4 This standard does not purport to address all of the
10000 ng/kg. This analyte is qualitatively and quantitatively
safety concerns, if any, associated with its use. It is the
determined by this method. This method adheres to multiple
responsibility of the user of this standard to establish appro-
reaction monitoring (MRM) mass spectrometry.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.2 The method detection limit (Note 1) (MDL) and report-
1.5 This international standard was developed in accor-
ing range (Note 2) for the target analyte are listed in Table 1.
dance with internationally recognized principles on standard-
NOTE 1—The MDL is determined following the Code of Federal
ization established in the Decision on Principles for the
Regulations, 40 CFR Part 136, Appendix B, as a guide utilizing solvent
Development of International Standards, Guides and Recom-
extraction of soil. Two-gram sample of Ottawa sand was utilized. A
detailedprocessdeterminingtheMDLisexplainedinthereferenceandis mendations issued by the World Trade Organization Technical
beyond the scope of this standard to be explained here.
Barriers to Trade (TBT) Committee.
NOTE 2—Reporting range concentration is calculated from Table 2
concentrations assuming a 50-µL injection of the Level 1 calibration
2. Referenced Documents
standard for TTPC, and the highest level calibration standard with a
2.1 ASTM Standards:
20-mL final extract volume of a 2-g soil sample. Volume variations will
change the reporting limit and ranges. D1193Specification for Reagent Water
D2777Practice for Determination of Precision and Bias of
1.2.1 Thereportinglimitinthistestmethodistheminimum
Applicable Test Methods of Committee D19 on Water
value below which data are documented as non-detects. Ana-
D5681Terminology for Waste and Waste Management
lyte detections between the method detection limit and the
D5847Practice for Writing Quality Control Specifications
reporting limit are estimated concentrations and are not re-
for Standard Test Methods for Water Analysis
ported following this test method. The reporting limit is
E2554Practice for Estimating and Monitoring the Uncer-
calculated from the concentration of the Level 1 calibration
tainty of Test Results of a Test Method Using Control
standard as shown in Table 2 for TTPC after taking into
Chart Techniques
account a 2-g sample weight and a final extract volume of
2.2 Other Documents:
EPAPublication SW-846Test Methods for Evaluating Solid
This test method is under the jurisdiction ofASTM Committee D34 on Waste
Waste, Physical/Chemical Methods
Management and is the direct responsibility of Subcommittee D34.01.06 on
Analytical Methods.
Current edition approved Feb. 1, 2020. Published February 2020. Originally For referenced ASTM standards, visit the ASTM website, www.astm.org, or
approved in 2015. Last previous edition approved in 2015 as D8018–15. DOI: contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
10.1520/D8018-15R20. Standards volume information, refer to the standard’s Document Summarypageon
More information on TTPC can be found at http://www.buruenergy.com/wp- the ASTM website.
content/uploads/BE-Environmental-Properties-of-Proposed- Biocide-BE-91.pdf Available from NationalTechnical Information Service (NTIS), 5301 Shawnee
(2014) and http://iaspub.epa.gov/sor_internet/registry/substreg/searchandretrieve/ Rd.,Alexandria,VA22312,http://www.ntis.govorathttp://www.epa.gov/epawaste/
advancedsearch/externalSearch.do?p_type=CASNO&p=81741-28-8 (2014). hazard/testmethods/index.htm.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D8018 − 15 (2020)
A
TABLE 1 Method Detection Limit and Reporting Range
based and alternative operating conditions can be used to
Analyte MDL (ng/kg) Reporting Range (ng/kg)
perform this method provided data quality objectives are
TTPC 32.7 250–10 000
attained. Mention of trade names or suppliers is not an
A
Acronyms are defined in 3.3.
endorsement of use; it is provided for informational purposes
only.Any apparatus, supply, standard, or reagent may be used
provided that it is shown to be acceptable to meet the
performance criteria of the method.
40 CFR Part 136,Appendix BDefinition and Procedure for
the Determination of the Method Detection Limit
4.2 ForTTPCanalysis,samplesareshippedtothelabonice
and analyzed within 14 days of collection.Asample (~2 g) is
3. Terminology
transferred to a VOA vial, a TTPC spike solution is added to
laboratorycontrolandmatrixspikesamplesbeforetheaddition
3.1 For determinations of terms used in this standard, refer
of acetone. An isotopically labeled TTPC surrogate could be
to Terminology D5681.
added at this point, presently requires a custom synthesis and
3.2 Definitions of Terms Specific to This Standard:
shouldbeincorporatedintothismethodbytheuserifrequested
3.2.1 batch QC, n—all the quality control samples and
by the customer. Then add 15 mL of acetone and hand shake
standards included in an analytical procedure.
or vortex for 1 min.The samples are allowed to settle, and are
3.2.2 reporting limit check sample, RLCS, n—this sample is
then filtered through a Nylon membrane syringe-driven filter
to verify that if the analyte was present at the reporting limit,
unit leavingthesolidsbehind,5mLofASTMType1wateris
it would be confidently identified.
added to the filtered extract and then analyzed by LC/MS/MS.
All concentrations reported, only to the reporting limit, using
3.3 Acronyms:
this method are based upon a dry weight basis.
3.3.1 CCC, n—continuing calibration check
3.3.2 IC, n—initial calibration 4.3 TTPC is identified by comparing the single reaction
monitoring (SRM) transition and its confirmatory SRM tran-
3.3.3 LC, n—liquid chromatography
sitions if correlated to the known standard SRM transition
3.3.4 LCS/LCSD, n—laboratory control sample/laboratory
(Table 3) and quantitated utilizing an external calibration. The
control sample duplicate
final report issued for each sample lists the concentration of
3.3.5 MDL, n—method detection limit
TTPC, if detected, or RL, if not detected, in ng/kg (dry weight
basis) and surrogate recovery, if available.
3.3.6 MeOH, n—methanol
–3
3.3.7 mM, n—millimolar,1×10 moles/L
5. Significance and Use
3.3.8 MRM, n—multiple reaction monitoring
5.1 This test method has been developed by the U.S. EPA
3.3.9 MS/MSD, n—matrix spike/matrix spike duplicate
Region 5 Chicago Regional Laboratory (CRL).
3.3.10 NA, adj—not available
5.2 TTPCmaybeusedinvariousindustrialandcommercial
3.3.11 ND, n—non-detect
products for use as a biocide. Products containing TTPC have
been approved for controlling algal, bacterial, and fungal
3.3.12 P&A—precision and accuracy
slimes in industrial water systems. TTPC should not be
3.3.13 PPT, n—parts per trillion
persistent in water but may be deposited in sediments at
3.3.14 QA, adj—quality assurance
concentrations of concern. Hence, there is a need for quick,
3.3.15 QC, adj—quality control
easy, and robust method to determine TTPC concentration at
trace levels in various soil matrices for understanding the
3.3.16 RL, n—reporting limit
sources and concentration levels in affected soils and sedi-
3.3.17 RLCS, n—reporting limit check sample
ments.
3.3.18 RSD, n—relative standard deviation
5.3 This method has been used to determine TTPC in sand,
3.3.19 RT, n—retention time
a commercial top soil, and four ASTM reference soils (Table
3.3.20 SDS, n—safety data sheets
4).
3.3.21 SRM, n—single reaction monitoring
6. Interferences
3.3.22 SS, n—surrogate standard
6.1 All glassware is washed in hot water with detergent and
3.3.23 TC, n—target compound
rinsed in hot water followed by distilled water. The glassware
3.3.24 TTPC—n-(tri-n-butyl)-n-tetradecylphosphonium
is then dried and heated in an oven at 250°C for 15 to 30 min.
chloride
3.3.25 VOA, n—volatile organic analysis
A custom synthesized surrogate, TTPC (D29), may be an inexpensive viable
surrogate.
4. Summary of Test Method
A Whatman Puradisc™ 25 NYL Disposable Filter Unit (diameter 25 mm,
0.2µm Nylon membrane syringe-driven filter unit) has been found suitable for use
4.1 The operating conditions presented in this test method
for this method; any filter unit may be used that meets the performance of this
have been successfully used in the determination of TTPC in
method may be used. The use of PTFE, PVDF, and polypropylene filter units
soil; however, this test method is intended to be performance resulted in poor performance.
D8018 − 15 (2020)
TABLE 2 Concentrations of Calibration Standards (ng/L)
Concentrations
LV1 LV2 LV3 LV4 LV5 LV6 LV7 LV8
(ng/L)
TTPC 25 50 100 200 400 600 800 1000
TABLE 3 Retention Times, SRM Ions, and Analyte-Specific Mass Spectrometer Parameters
Primary/
Retention Time
Chemical Primary/Confirmatory SRM Transition Cone (V) Collision (eV) Confirmatory SRM
(minutes)
Area Ratio
Primary (Quantitation) 399.5→ 229.3 40 45 NA
TTPC First Confirmatory 399.5→ 75.9 40 46 8.1 0.92
Second Confirmatory 399.5→ 343.5 40 40 3.02
TABLE 4 Single-Laboratory Recovery Data in Six Soil Types
Ottawa Sand ASTM Frederick Sand ASTM Silt
Sample
(2500 ng/kg spike) (2500 ng/kg spike) (2500 ng/kg spike)
MB 1 MB 2 P&A 1 2074.5 2121.4 1477.8
P&A 2 2244.6 2145.9 1482.3
P&A 3 2286.4 2171.3 1364.2
P&A 4 2077.8 2215.4 1543.9
P&A 5 2192.1 2038.5 1545.7
P&A 6 1953.1 2079.2 1462.1
Average Recovery (ng/kg) 2138.1 2128.6 1479.3
% Average Recovery 85.5 85.1 59.2
Standard Deviation 125.0 63.7 66.5
RSD (%) 5.8 3.0 4.5
ASTM Lean Clay ASTM Fat Clay Top Soil
Sample
(2500 ng/kg spike) (2500 ng/kg spike) (2500 ng/kg spike)
MB 1 MB 2 P&A 1 394.6 790.2 1764.4
P&A 2 986.4 783.2 1750.1
P&A 3 386.4 772.4 1758.9
P&A 4 392.4 774.9 1771.6
P&A 5 435.3 791.7 1659.6
P&A 6 375.5 751.7 1778.3
Average Recovery (ng/kg) 395.1 777.4 1747.2
% Average Recovery 15.8 31.1 69.9
Standard Deviation 20.8 14.8 44.0
RSD (%) 5.3 1.9 2.5
Allglasswareissubsequentlyrinsedorsonicated,orboth,with 6.4 Matrix interferences may be caused by contaminants in
acetone, n-propanol, or acetonitrile, or combinations thereof. the sample. The extent of matrix interferences can vary
considerably depending on variations in the sample matrices.
6.2 TTPC should not be a common contaminant found in a
laboratory, unless involved in the analysis or matrices that
6.5 Automatic pipettes with polypropylene tips are used
contain TTPC. TTPC has been found to continue to adhere to with this method. The use of glass syringes for standards
glassware and syringes after routine glassware washing. Rins-
preparation, spiking, and calibrations generated erratic results
ingglasswarewithacetone,n-propanol,oracetonitrile,orboth, and should be avoided.Athoroughly cleaned 20-mLhypoder-
or even sonication, may be required to remove TTPC. All of
micglasssyringewithaNylonfilterisusedtofilterthe20-mL
thematerialsandsuppliesareroutinelydemonstratedtobefree
sample extracts and has been shown to perform well when
from interferences and TTPC by analyzing laboratory blanks filtering these large volumes. Preparing small volumes of
under the same conditions as the samples. If found, measures
samplesandstandards,like1-mLcalibrationstandards,maybe
shouldbetakentoremovethecontaminationordatashouldbe affected by adhesion of TTPC to the syringe barrel or plunger.
qualified;backgroundsubtractionofblankcontaminationisnot
The use of PTFE, PVDF, and polypropylene filter units
allowed. resulted in poor performance and low recoveries.
6.3 All reagents and solvents should be pesticide residue
NOTE3—Theuseofpolypropylenedisposablesyringestofiltersamples
purity or higher to minimize interference problems. and polypropylene LC vials with polyethylene caps have been shown to
D8018 − 15 (2020)
perform in the performance criteria of the method and may be used.
American Chemical Society. Other reagent grades may be
used provided they are first determined to be of sufficiently
7. Apparatus
highpuritytopermittheirusewithoutaffectingtheaccuracyof
the measurements.
7.1 LC/MS/MS System:
7.1.1 Liquid Chromatography System —A complete LC
8.2 Purity of Water—Unless otherwise indicated, references
system is required in order to analyze samples; this should
towatershallbeunderstoodtomeanreagentwaterconforming
include a sample injection system, a solvent pumping system
toType1ofSpecificationD1193.Itshallbedemonstratedthat
capable of mixing solvents, a sample compartment capable of
this water does not contain contaminants at concentrations
maintaining required temperature, and a temperature-
sufficient to interfere with the analysis.
controlled column compartment.An LC system that is capable
8.3 Gases—Ultrapure nitrogen and argon.
of performing at the flows, pressures, controlled temperatures,
8.4 Acetone (CAS # 67-64-1).
sample volumes, and requirements of the standard shall be
used.
8.5 Acetonitrile (CAS # 75-05-8).
7.1.2 Analytical Column —A reverse-phase C18 particle
8.6 Methanol (CAS # 67-56-1).
columnwasusedtodevelopthistestmethod.Anycolumnthat
8.7 Ammonium acetate (CAS # 631-61-8).
achieves adequate resolution may be used.The retention times
andorderofelutionmaychangedependingonthecolumnused
8.8 2-Propanol (isopropyl alcohol, CAS # 67-63-0).
and need to be monitored.
8.9 Ottawa sand (CAS # 14808-60-7).
7.2 Tandem Mass Spectrometer System —An MS/MS sys-
8.10 (Tri-n-butyl)-n-tetradecylphosphonium chloride (CAS
tem capable of multiple reaction monitoring (MRM) analysis
# 81741-28-8).
or any system that is capable of meeting the requirements in
this standard shall be used.
9. Hazards
7.3 Adjustable Volume Pipettes—10, 20, 100, and 1000 µL
9.1 Normal laboratory safety applies to this test method.
and 5 and 10 mL.
Analysts should wear safety glasses, gloves, and lab coats
7.3.1 Pipette Tips—Polypropylene pipette tips free of re-
when working in the lab. Analysts should review the Safety
lease agents or low retention coating of various sizes.
Data Sheets (SDS) for all reagents used in this test method.
7.4 Class A Volumetric Glassware.
7.5 Filtration Device: 10. Sampling
7.5.1 Hypodermic Syringe—A luer-lock tip glass syringe
10.1 Sampling and Preservation—Grab samples are col-
capable of holding a syringe-driven filter unit.
lected in glass containers with polytetrafluoroethylene-lined
7.5.2 A 20-mL lock-tip glass syringe size is recommended
caps.As part of the overall quality assurance program for this
since a 20-mL sample size is used in this test method.
test method, field blanks exposed to the same field conditions
7.5.3 Filter Unit —Nylonfilterunitswereusedtofilterthe
as samples are collected and analyzed according to this test
samples.
methodtoassessthepotentialforfieldcontamination.Thistest
method is based on a 2-g sample size per analysis. If different
7.6 Vials—2-mL autosampler vials with pre-slit PTFE/
samplesizesareused,spikingsolutionamountsmayneedtobe
silicone septa or equivalent.
modified. EPApublication SW-846 may be used as a sampling
7.7 VOA Vials—40 mL.
guide. Samples shall be shipped on ice with a trip blank. Once
received, the sample temperature is taken and should be less
8. Reagents and Materials
than6°C.Ifthereceivingtemperatureisgreaterthan6°C,the
8.1 Purity of Reagents—High performance liquid chroma-
sample temperature is noted in the case narrative accompany-
tography (HPLC) pesticide residue analysis and spectropho-
ing the data. Samples should be stored refrigerated between 0
tometry grade chemicals shall be used in all tests. Unless
and6°Cfromthetimeofcollectionuntilanalysis.Thesample
indicated otherwise, it is intended that all reagents shall
should be analyzed within 14 days of collection. No holding
conform to the Committee on Analytical Reagents of the
time study has been done on the various soil matrices tested in
this test method. Holding time may vary depending on the
matrix and individual laboratories should determine the hold-
ing time in their matrix.
A Waters Acquity UPLC H-Class System, or equivalent, has been found
suitable for use.
A Waters Acquity UPLC BEH C18, 2.1 × 100 mm and 1.7 µm particle size
column, or equivalent, has been found suitable for use. It was used to develop this
test method and generate the precision and bias data presented in Section 16. Reagent Chemicals, American Chemical Society Specifications, American
AWaters Xevo TQ-S triple quadrupole mass spectrometer, or equivalent, has Chemical Society, Washington, D.C. For Suggestions on the testing of reagents not
been found suitable for use. listed by the American Chemical Society, see Analar Standards for Laboratory
AWhatman Puradisc™ 25 NYLDisposable Filter Unit (diameter 25 mm, 0.2 Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
µm Nylon membrane syringe-driven filter unit) has been found suitable for use for and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
this method; any filter unit may be used that meets the performance of this method MD.
may be used. The use of PTFE, PVDF, and polypropylene filter units resulted in A guide to help and determine sample holding times can be found at
poor performance. http://www.epa.vom/esd/cmb/resaerch/bs_033cmb06.pdf (2014).
D8018 − 15 (2020)
11. Preparation of LC/MS/MS 12. Calibration and Standardization
11.1 LC Chromatograph Operating Conditions:
12.1 The mass spectrometer shall be calibrated as per
11.1.1 Injections of all standards and samples are made at a
manufacturer’s specifications before analysis. Analytical val-
50-µL volume. Other injection volumes may be used to
uessatisfyingtestmethodcriteriahavebeenachievedusingthe
optimize conditions. Standards and sample extracts shall be in
following procedures. Prepare all solutions in the lab using
a 75:25 acetone:water solution. In the case of extreme concen-
Class A volumetric glassware.
tration differences amongst samples, it is wise to analyze a
12.2 Calibration and Standardization—To calibrate the
blank after a concentrated sample and before a diluted sample
instrument, analyze eight calibration standards of the TTPC
to minimize carryover of analytes from injection to injection.
compound prior to sample analysis as shown in Table 2.
However, there should not be carryover between samples.The
Calibration stock standard solution is prepared from the target
LC utilized to develop this test method has a flow-through LC
spike solution directly to ensure consistency. Stock standard
needle design. The gradient conditions for liquid chromatog-
Solution A containing the TTPC is prepared at Level 8
raphy are shown in Table 5.
concentration and aliquots of that solution are diluted to
11.2 LC Sample Manager Conditions:
prepare Levels 1 through 7. The following steps will produce
11.2.1 Needle Wash Solvent—60 % acetonitrile/40 %
standards with the concentration values shown in Table 2.The
2-propanol. Eight-second wash time before and after injection.
analyst is responsible for recording initial component weights
Instrumentmanufacturer’sspecificationsshouldbefollowedin
carefully when working with pure materials and correctly
order to eliminate sample carryover.
carrying the weights through the dilution calculations. At a
11.2.2 Temperatures—Column, 35 °C; sample
minimum, five calibration levels are required when using a
compartment, 15°C.
linear calibration curve and six calibration levels are required
11.2.3 Seal Wash—Solvent: 50% methanol/50% water;
whenusingaquadraticcalibrationcurve.Aninitialeight-point
Time: 5 min.
curvemaybeusedtoallowforthedroppingofthelowerlevel
calibration points if the individual laboratory’s instrument
11.3 Mass Spectrometer Parameters:
cannot achieve low detection limits. This should allow for at
11.3.1 To acquire the maximum number of data points per
least a five or six-point calibration curve to be obtained. No
SRM channel while maintaining adequate sensitivity, the tune
problems were encountered while using the eight-point cali-
parametersmaybeoptimizedaccordingtotheinstrumentused.
bration curve in developing this test method.
Each peak requires at least ten scans per peak for adequate
quantitation. Variable parameters regarding retention times,
12.2.1 CalibrationstockstandardSolutionA(Level8,Table
SRM transitions, and cone and collision energies are shown in 2) is prepared from the target spike solution directly to ensure
Table 3. Mass spectrometer parameters used in the develop-
consistency. 500 µL of TTPC target spike solution (100 µg/L,
ment of this test method are listed below: 12.7) is added to a 50-mL volumetric flask and diluted to
50mLwith 75:25 acetone:water. The preparation of the Level
The instrument is set in the Electrospray positive source setting
Capillary Voltage: 1 kV
8standardcanbeaccomplishedusingappropriatevolumesand
Cone: Variable depending on analyte
concentrations of stock solutions as per a particular laborato-
Extractor: 2 V
ry’s standard procedure.
Source Temperature: 150 °C
Desolvation Gas Temperature: 500 °C
12.2.2 Aliquots of Solution A are then diluted with 75:25
Desolvation Gas Flow: 900 L/hr
acetone:water to prepare the desired calibration levels in 2-mL
Cone Gas Flow: 150 L/hr
Collision Gas Flow: 0.15 mL/min amber glass LC vials (Table 6). The calibration vials shall be
Low Mass Resolution 1: 3
used w
...