Triallate (PC 078802)
MRIDs 50432501 / 50352202
Analytical method for triallate and its metabolite TCPSA in water
Reports: ECM: EPA MRID No.: 50432501. Wu, X. 2016. Validation of the Analytical
Method for the Determination of Triallate and TCPSA in Aqueous Matrices
by LC-MS/MS. Report prepared by Smithers Viscient, Wareham
Massachusetts, and sponsored and submitted by Gowan Company, Yuma,
Arizona; 115 pages. Smithers Viscient Study No. 12791.6265. Final report
issued December 19, 2016.
Document No.:
Guideline:
Statements:
Classification:
PC Code:
Final EPA
Reviewer:
CDM/CSS-
Dynamac JV
Reviewers:
ILV: EPA MRID No. 50352202. MacGregor, J.A., E.S. Bodle, and RL.
VanHoven. 2017. INDEPENDENT LABORATORY VALIDATION OF A
METHOD FOR THE DETERMINATION OF TRIALLATE AND TCPSA
IN AQUEOUS MATRICES BY LC/MS/MS. Report prepared by Wildlife
International (now doing business as EAG), Easton, Maryland, sponsored and
submitted by Gowan Company, Yuma, Arizona; 113 pages. Project No.
334C-134. Final report issued July 21, 2017.
MRIDs 50432501 & 50352202
850.6100
ECM: The study was conducted in accordance with USEPA FIFRA (40 CFR
160) and OECD Good Laboratory Practice (GLP) standards (p. 3 of MRID
50432501). Signed and dated No Data Confidentiality, GLP, and Quality
Assurance statements were provided (pp. 2-4). Authenticity statement was
included with the GLP statement (p. 4).
ILV: The study was conducted in accordance with USEPA FIFRA GLP
standards (p. 3 of MRID 50352202). Signed and dated No Data
Confidentiality, GLP, and Quality Assurance statements were provided (pp.
2-4). An authenticity statement was not included.
This analytical method is classified as Unacceptable. The LOD was not
reported in the ILV. The specificity of the method for TCPSA was not
supported by the ECM and ILV representative chromatograms. The TCPSA
confirmation analysis was not independently validated. ECM linearity was
not satisfactory for triallate.
078802
A'j a Duncan,
Chemist
. . Digitally signed by Duncan, Aja
Signature: Duncan, Aja ^o^018-09-1015:3&54
Date: 9/10/18
Lisa Muto,
Environmental Scientist
Kathleen Ferguson, Ph.D.,
Environmental Scientist
Signature:
Date:
Signature:
6/21/18
Date:
6/21/18
This Data Evaluation Record may have been altered by the Environmental Fate and Effects
Division subsequent to signing by CDM CSS-Dynamac .IVpersonnel. The CDM CSS-Dynamac
Joint Venture role does not include establishing Agency policies.
Page 1 of 11
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
Executive Summary
The analytical method, Smithers Viscient Study No. 12791.6265, is designed for the quantitative
determination of triallate and its metabolite TCPSA in water at the LOQ of 0.100 |ig/L using
LC/MS/MS. The LOQ is less than the lowest toxicological level of concern (14 |ig/L; USEPA,
2014) in water for the two analytes. The ECM and ILV validated the method using ground and
surface water matrices; however, the ECM matrices were not well-characterized. The ILV validated
the ECM method for the quantitation and confirmation analyses of triallate and the quantitation
analysis of TCPSA in two water matrices in the first trial with insignificant modifications to the
analytical instruments. The ECM method for the confirmation analyses of TCPSA in two water
matrices was validated in the second trial with modifications to sample processing and analytical
parameters. These modifications did not warrant the submission of an updated ECM since a
confirmatory method is not usually required when LC/MS and GC/MS is the primary method;
however, based on ILV communications, the ECM should have been updated to indicate that the
TCPSA confirmation analysis is used to confirm the identity of TCPSA, not quantitative results of
the primary analysis. All ECM and ILV data regarding repeatability, accuracy, and precision were
satisfactory for both analytes, based on the quantitation ion results; however, specificity of the
method for TCPSA was not supported by the ECM and ILV representative chromatograms due to
the fact that the LOQ peak was broad, small, and not well-distinguished from the baseline noise.
ECM linearity was unsatisfactory for triallate. The LOD was not reported in the ILV.
Table 1. Analytical Method Summary
Analyte(s) by
Pesticide1
MRID
EPA
Review
Matrix
Method Date
(dd/mm/yyyy)
Registrant
Analysis
Limit of
Quantitation
(LOQ)
Environmental
Chemistry
Method
Independent
Laboratory
Validation
Triallate
50432501
50352202
Water1-2
19/12/2016
Gowan
Company
LC/MS/MS
0.100 ng/L
TCPSA
1 In the ECM, the ground water was obtained from a laboratory well, reconstituted for hardness based on U.S. EPA
1975 hard water specifications, and filtered (Amberlite XAD-7 resin column) prior to use; surface water (pH 6.10 and
6.36 mg/L dissolved oxygen content), obtained from Taunton River, Taunton, Massachusetts. Water characterization
was incomplete or absent.
2 In the ILV, the ground water (well; pH 8.03-8.15 and hardness 144-145 mg equiv. CaCCh/L) obtained from EAG
Laboratories aquatic testing facility and surface water (lake; pH 7.00 and hardness 64.0 mg equiv. CaCCh/L) obtained
from Tuckahoe Lake, Ridgely, Maryland, were used in the study.
Page 2 of 11
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
I. Principle of the Method
Samples (5.00 mL) were transferred to 10-mL glass vials and fortified, as necessary, with mixed
fortification solutions of triallate and TCPSA in acetonitrile (pp. 18, 21-25 of MRID 50432501).
The sample volumes were adjusted to 10 mL with acetonitrile. The samples for triallate and TCPSA
primary analysis on the T3 column were further diluted into the calibration standard range with
acetonitrile:purified reagent water (50:50, v:v); samples for TCPSA confirmatory analysis on the
HILIC column were further diluted into the calibration standard range with acetonitrile:purified
reagent water (90:10, v:v). All samples were then centrifuged at 13,000 rpm for 5 minutes; the
supernatant was transferred to HPLC vials and analyzed by LC/MS/MS.
Samples were analyzed for both analytes using an Agilent 1200 HPLC system coupled to an AB
Sciex API 5000 mass spectrometer with an ESI Turbo V source (pp. 25-28 of MRID 50432501).
The LC/MS conditions for triallate consisted of a XBridge C18 column (2.1 x 50 mm, 2.5-|am;
column temperature 40°C), a mobile phase of (A) water with 0.1% formic acid and (B) acetonitrile
with 0.1% formic acid [percent A:B (v:v) at 0.00-0.50 min. 75:25, 4.00-6.00 min. 0:100, 6.10-7.50
min. 75:25] and MS/MS detection in positive ion mode (ionization temperature 500°C). Injection
volume was 100 |aL. Two ion transitions were monitored (quantitation and confirmatory,
respectively) as follows: m/z 304.1—>86.1 and m/z 304.1—>142.8 for triallate. Retention times were
3.86-3.88 minutes for triallate in both matrices. The LC/MS conditions for primary analysis of
TCPSA consisted of a Atlantis® T3 column (4.6 x 100 mm, 3-|am; column temperature 40°C), a
isocratic mobile phase at 50:50, v:v, of (A) water with 0.1% formic acid and (B) acetonitrile with
0.1% formic acid. The LC/MS conditions for confirmatory analysis of TCPSA consisted of
Atlantis® HILIC silica column (3.0 x 100 mm, 3-|am; column temperature 40°C), a isocratic mobile
phase at 10:90, v:v, of (A) water with 0.1% formic acid and (B) acetonitrile with 0.1% formic acid.
MS/MS detection was conducted in negative ion mode (ionization temperature 500°C). Injection
volume was 100 |aL for primary and confirmatory analyses. One ion transition was monitored for
TCPSA primary and confirmatory analysis: m/z 224.8—>79.8. Retention times were 1.63-1.66 and
2.02-2.03 minutes for TCPSA for primary and confirmatory analysis, respectively.
In the ILV, the ECM was performed as written, except for modifications for the TCPSA
confirmatory analysis processing and analytical parameters and a few minor modifications of
analytical instruments (pp. 14-17; Tables 1-3, pp. 23-25 of MRID 50352202). For the TCPSA
confirmatory analysis, the second dilution was performed with 100% acetonitrile and the HPLC
isocratic mobile phase was adjusted to 5:95, v:v, of (A) water with 0.1% formic acid and (B)
acetonitrile with 0.1% formic acid; also, matrix-matched calibration standards were used for the
surface water analysis. An Agilent 1200 HPLC System coupled to an AB Sciex API 5000 Turbo-V
Ion Spray mass spectrometer was used. The LC/MS conditions were the same, except for the
modification of the HPLC isocratic mobile phase of TCPSA confirmatory analysis. Two ion
transitions were monitored for triallate (quantitation and confirmatory, respectively) as follows: m/z
304.1—>85.8 and m/z 304.1—>-142.8. One ion transition was monitored for TCPSA primary and
confirmatory analysis: m/z 224.8—>79.8. Retention times were ca. 4.9 and 5.8 minutes for triallate
analysis in ground and surface water, respectively, and were ca. 1.9-2.0 and 2.0-3.1 minutes for
TCPSA analysis in ground and surface water, respectively. No significant modifications were made
by the ILV.
The Limit of Quantification (LOQ) was 0.100 |ig/L for triallate and TCPSA in water in the ECM
and ILV (pp. 29-30, 35-38 of MRID 50432501; p. 11 of MRID 50352202). The Limit of Detection
Page 3 of 11
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
(LOD) was 0.00104-0.0215 |ig/L for triallate and 0.0151-0.103 |ig/L for TCPSA in surface and
ground water matrices in the ECM; the LOD was not reported in the ILV.
II. Recovery Findings
ECM (MRID 50432501): Mean recoveries and relative standard deviations (RSDs) were within
guideline requirements (mean 70-120%; RSD <20%) for analysis of triallate and its metabolite
TCPSA in two water matrices at fortification levels of 0.100 |ig/L (LOQ) and 1.00 |ig/L (lOxLOQ;
Tables 1-8, pp. 41-48). Performance data (recovery results) from primary and confirmatory analyses
were comparable. Ground water was obtained from a laboratory well, reconstituted for hardness
based on U.S. EPA 1975 hard water specifications, and filtered (Amberlite XAD-7 resin column)
prior to use; surface water (pH 6.10 and 6.36 mg/L dissolved oxygen content), obtained from
Taunton River, Taunton, Massachusetts (p. 16). Water characterization was incomplete or absent.
ILV (MRID 50352202): Mean recoveries and RSDs were within guideline requirements for
analysis of triallate and its metabolite TCPSA in two water matrices at fortification levels of 0.100
|ig/L (LOQ) and 1.00 |ig/L (lOxLOQ), except for the confirmation ion analysis of TCPSA in
ground water at the LOQ (mean 155% and RSD 66%; Tables 4-11, pp. 26-33). This deviation did
not affect the validity of the study since a confirmatory method is not usually required when LC/MS
and GC/MS is the primary method; statistics for this sample set were reviewer-calculated based on
all five recovery values in the study report. Performance data (recovery results) from primary and
confirmatory analyses were comparable, except for TCPSA in ground water at the LOQ. Ground
water (well; pH 8.03-8.15 and hardness 144-145 mg equiv. CaC03/L) obtained from EAG
Laboratories aquatic testing facility and surface water (lake; pH 7.00 and hardness 64.0 mg equiv.
CaC03/L) obtained from Tuckahoe Lake, Ridgely, Maryland, were used in the study (p. 12;
Appendices IV-V, pp. 100-101). The ECM method for the quantitation and confirmation analyses
of triallate and the quantitation analysis of TCPSA in two water matrices was validated in the first
trial with insignificant modifications to the analytical instruments (pp. 11, 16-17; Appendix VI, pp.
109-112). The ECM method for the confirmation analyses of TCPSA in two water matrices was
validated in the second trial with modifications to sample processing and analytical parameters.
These modifications did not warrant the submission of an updated ECM since a confirmatory
method is not usually required when LC/MS and GC/MS is the primary method; however, based on
ILV communications, the ECM should have been updated to indicate that the TCPSA confirmation
analysis is used to confirm the identity of TCPSA, not quantitative results of the primary analysis.
Page 4 of 11
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
Table 2. Initial Validation Method Recoveries for Triallate and TCPSA in Water1-2
Analyte
Fortification
Level (jig/L)
Number
of Tests
Recovery
Range (%)
Mean
Recovery (%)
Standard
Deviation (%)
Relative Standard
Deviation (%)2
Ground Water
Quantitation ion
Triallate
0.100 (LOQ)
5
97.2-109
105
5.42
5.17
1.00
5
95.5-116
108
9.34
8.69
TCPSA
0.100 (LOQ)
5
84.0-112
95.5
10.7
11.2
1.00
5
93.9-116
105
9.59
9.15
Confirmation ion or analysis
Triallate
0.100 (LOQ)
5
96.3-108
103
4.76
4.61
1.00
5
94.3-116
106
8.34
7.89
TCPSA
0.100 (LOQ)
5
76.7-99.3
88.9
9.74
11.0
1.00
5
84.6-107
93.4
9.15
9.80
Surface Water
Quantitation ion
Triallate
0.100 (LOQ)
5
110-118
114
3.63
3.19
1.00
5
106-115
109
3.63
3.34
TCPSA
0.100 (LOQ)
5
92.6-107
99.1
5.35
5.39
1.00
5
106-117
111
4.22
3.81
Confirmation ion or analysis
Triallate
0.100 (LOQ)
5
99.2-111
106
4.95
4.66
1.00
5
100-107
104
2.51
2.42
TCPSA
0.100 (LOQ)
5
90.0-104
97.6
5.12
5.24
1.00
5
110-118
113
2.95
2.61
Data (uncorrected recovery results, p. 30) were obtained from Tables 1-8, pp. 41-48 of MRID 50432501.
1 The ground water was obtained from a laboratory well, reconstituted for hardness based on U.S. EPA 1975 hard water
specifications, and filtered (Amberlite XAD-7 resin column) prior to use; surface water (pH 6.10 and 6.36 mg/L
dissolved oxygen content), obtained from Taunton River, Taunton, Massachusetts (p. 16). Water characterization was
incomplete or absent.
2 Two ion transitions were monitored (quantitation and confirmatory, respectively) as follows: m/z 304.1—>86.1 and m/z
304.1—>142.8 for triallate. One ion transition was monitored for TCPSA primary and confirmatory analysis: m/z
224.8—>79.8; different analytical columns were used for primary and confirmatory analyses.
Page 5 of 11
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
Table 3. Independent Validal
tion Method Recoveries for Triallal
te and TCPSA in Water1-2
Analyte
Fortification
Level (jig/L)
Number
of Tests
Recovery
Range (%)
Mean
Recovery (%)
Standard
Deviation (%)
Relative Standard
Deviation (%)2
Ground Water
Quantitation ion
Triallate
0.100 (LOQ)
5
97.6-112
107
5.52
5.16
1.00
5
107-112
109
2.00
1.83
TCPSA
0.100 (LOQ)
5
82.2-103
87.8
8.80
10.0
1.00
5
101-122
109
7.89
7.24
Confirmation ion or analysis
Triallate
0.100 (LOQ)
5
99.8-111
107
4.36
4.07
1.00
5
105-115
111
4.04
3.64
TCPSA
0.100 (LOQ)
53
104-339
155
103
66
1.00
5
73.7-85.7
82.1
4.98
6.07
Surface Water
Quantitation ion
Triallate
0.100 (LOQ)
5
104-108
106
1.64
1.55
1.00
5
104-110
108
2.88
2.68
TCPSA
0.100 (LOQ)
5
80.1-98.1
91.3
6.89
7.55
1.00
5
83.5-96.0
91.7
6.26
6.82
Confirmation ion or analysis
Triallate
0.100 (LOQ)
5
100-109
104
3.29
3.16
1.00
5
97.3-112
107
6.33
5.92
TCPSA
0.100 (LOQ)
5
83.3-117
97.5
12.8
13.1
1.00
5
109-126
114
6.89
6.04
Data (uncorrected recovery results, pp. 17-19) were obtained from Tables 4-11, pp. 26-33 of MRID 50352202.
1 The ground water (well; pH 8.03-8.15 and hardness 144-145 mg equiv. CaCCb/L) obtained from EAG Laboratories
aquatic testing facility and surface water (lake; pH 7.00 and hardness 64.0 mg equiv. CaCCb/L) obtained from
Tuckahoe Lake, Ridgely, Maryland, were used in the study (p. 12; Appendices IV-V, pp. 100-101).
2 Two ion transitions were monitored (quantitation and confirmatory, respectively) as follows: m/z 304.1—>85.8 and m/z
304.1—>142.8 for triallate. One ion transition was monitored for TCPSA primary and confirmatory analysis: m/z
224.8—>79.8; different analytical columns were used for primary and confirmatory analyses.
3 Mean standard deviation and relative standard deviation were reviewer-calculated based on all five recovery values
in the study report; the study author omitted one recovery value (339%) from the statistics since it was deemed to be
an outlier.
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
III. Method Characteristics
The LOQ was 0.100 |ig/L for triallate and TCPSA in water in the ECM and ILV (pp. 29-30, 35-38
of MRID 50432501; p. 11 of MRID 50352202). In the ECM, the LOQ was defined as the lowest
fortification level, and blank values should not be >30% of the LOQ; no calculations or
comparisons to background levels were reported to justify the LOQ for the method in the ECM. In
the ILV, the LOQ was reported from the ECM without justification. The LOD was 0.00104-0.0215
|ig/L for triallate and 0.0151-0.103 |ig/L for TCPSA in surface and ground water matrices in the
ECM; the LOD was not reported in the ILV. The LOD was calculated in the ECM using the
following equation:
LOD = (3x(SNcti)/(RespLs) x ConcLS
Where, LOD is the limit of detection of the analysis, SNcti is the mean signal to noise in height of
the control samples (or Blanks), RespLs is the mean response in height of the two low calibration
standards, and ConcLS is the concentration of the low calibration standard.
Table 4. Method Characteristics
Analyte1
Triallate
TCPSA
Limit of
Quantitation (LOQ)
ECM
0.100 ng/L
ILV
Limit of Detection
(LOD)
ECM
Ground
0.00370 (ig/L (Q)
0.00104 (ig/L (C)
0.0151 (ig/L (Q)
0.0624 (ig/L (C)
Surface
0.0215 (ig/L (Q)
0.00167 (ig/L (C)
0.0351 (ig/L (Q)
0.103 (ig/L (C)
ILV
Not reported
Linearity
(calibration curve r2
and concentration
range)
ECM
Ground
r2 = 0.9946 (Q)
r2 = 0.9940 (C)
r2 = 0.9954 (Q)
r2 = 0.9962 (C)
Surface
r2 = 0.9948 (Q)
r = 0.9950 (C)
r2 = 0.9990 (Q)
r2 = 0.9934 (C)
ILV1
Ground
r2 = 0.9990 (Q)
r2 = 0.9987 (Q)
Surface
Not reported
Range
0.005-0.500 (ig/L
Repeatable
ECM2
Yes at LOQ and lOxLOQ
(poorly characterized ground and surface water matrices).
ILV3'4
Yes at LOQ and lOxLOQ
(characterized ground and surface
water matrices).
Yes at LOQ and lOxLOQ, except
for LOQ C (mean 155%, RSD
66%; characterized ground water
matrices).5
Yes at LOQ and lOxLOQ
(characterized surface water
matrices).
Reproducible
Yes at LOQ and lOxLOQ
Specific
ECM
Yes, matrix interferences were <
14% of the LOQ (based on peak
area).
No, LOQ peak was small, broad,
and barely resolved from the
baseline.6 Matrix interferences
were < 6% of the LOQ (based on
peak area).
ILV
Only quantitation analysis chromatograms were provided.
Page 7 of 11
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
Analyte1
Triallate
TCPSA
Yes, matrix interferences were <
11% of the LOQ (based on peak
area).
Yes in surface water: matrix
interferences were < 10% of the
LOQ (based on peak area). LOQ
peak was broad.
No in ground water: matrix
interferences were ca. 66% of the
LOQ (based on peak area).7 LOQ
peak was broad and small
compared to baseline noise.
Data were obtained from pp. 29-31, 35-38 (LOQ/LOD); p. 32 (correlation coefficients); Tables 1-8, pp. 41-48 (recovery
data); Figures 1-47, pp. 57-103 (cliroinatograms) of MRID 50432501; p. 11 (LOQ); Tables 4-11, pp. 26-33 (recovery
data); Figures 1-2, pp. 34-35 (calibration curves); Figures 3-8, pp. 36-41 (cliroinatograms) of MRID 50352202; and
DER Attachment 2. Q = Quantitation ion transition; C = Confirmation ion transition or analysis.
1 Correlation coefficients (r2) values were reviewer-calculated from r values provided in the study report (Figures 1-2,
pp. 34-35 of MRID 50352202; DER Attachment 2). Only one calibration curve per analyte was presented: the
quantitation ion from the ground water analysis. Solvent standards were used for all analyses, except the TCPSA
confirmation ion analysis in surface water (pp. 13-14). The reviewer limited the calculated r2 to 4 significant figures
although 7 significant figures were reported in the ECM for r.
2 In the ECM, the ground water was obtained from a laboratory well, reconstituted for hardness based on U.S. EPA
1975 hard water specifications, and filtered (Amberlite XAD-7 resin column) prior to use; surface water (pH 6.10 and
6.36 mg/L dissolved oxygen content), obtained from Taunton River, Taunton Massachusetts (p. 16 of MRID
50432501). Water characterization was incomplete or absent.
3 In the ILV, the ground water (well; pH 8.03-8.15 and hardness 144-145 mg equiv. CaCCh/L) obtained from EAG
Laboratories aquatic testing facility and surface water (lake; pH 7.00 and hardness 64.0 mg equiv. CaCCb/L) obtained
fromTuckahoe Lake, Ridgely, Maryland, were used in the study (p. 12; Appendices IV-V, pp. 100-101 of MRID
50352202).
4 The ILV validated the ECM method for the quantitation and confirmation analyses of triallate and the quantitation
analysis of TCPSA in two water matrices in the first trial with insignificant modifications to the analytical
instruments (pp. 11, 16-17; Appendix VI, pp. 109-112 of MRID 50352202). The ECM method for the confirmation
analyses of TCPSA in two water matrices was validated in the second trial with modifications to sample processing
and analytical parameters. These modifications did not warrant the submission of an updated ECM since a
confirmatory method is not usually required when LC/MS and GC/MS is the primary method
5 A confirmatory method is not usually required when LC/MS and GC/MS is the primary method; therefore, the
deviation of repeatability and precision in the confirmation analysis does not affect the validity of the method.
6 Based on Figure 16, p. 72; Figure 22, p. 78; Figure 40, p. 96; and Figure 46, p. 102 of MRID 50432501.
7 Based on Figure 7, p. 40 of MRID 50352202. The reviewer noted that the study author quantified the residues in the
controls as 0.995.
IV. Method Deficiencies and Reviewer's Comments
1. The specificity of the method for TCPSA was not supported by the ECM and ILV
representative chromatograms. In the ILV, chromatograms from the surface water analysis
were acceptable, even though the LOQ peak was broad; however, chromatograms from the
ground water analysis showed that matrix interferences were ca. 66% (based on peak area)
and the LOQ peak was broad and small compared to baseline noise (Figure 7, p. 40 of
MRID 50352202). In the ILV, only chromatograms from the quantitation analysis were
provided for review. In the ECM, the LOQ peak of TCPSA was small, broad, and barely
resolved from the baseline in both water matrices (Figure 16, p. 72; Figure 22, p. 78; Figure
40, p. 96; and Figure 46, p. 102 of MRID 50432501).
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
2. In the ILV, the LOD was not reported. Also, the calibration curves and correlation
coefficients were not provided for the surface water sets. Solvent standards were used for all
analyses, except the TCPSA confirmation ion analysis in surface water for which matrix-
matched standards were used (pp. 13-14). All linearity data should be provided to assess the
accuracy of the recovery data.
3. Performance data was not satisfactory for the ILV confirmation ion analysis of TCPSA in
ground water (mean 155%, RSD 66%; Tables 4-11, pp. 26-33 of MRID 50352202). OCSPP
guideline requirements state that the mean recovery is 70-120%) and the RSD is <20%. This
guideline deviation is not substantial since a confirmatory method is not typically required
where GC/MS and/or LC/MS methods are used as the primary method(s) to generate study
data.
The reviewer noted that matrix-matched calibration standards were used for the ILV
confirmation ion analysis of TCPSA in surface water, which had acceptable recovery results
(p. 14; Tables 4-11, pp. 26-33 of MRID 50352202).
4. In the ECM, the linearity was not satisfactory for triallate, r2 = 0.9946-0.9948 (Q) in both
matrices and 0.9940 (C) in ground water (p. 32 of MRID 50432501). Linearity is
satisfactory when r2 > 0.995. However, in the case of the ILV confirmation ion analysis, the
reviewer noted that a confirmatory method is not typically required where GC/MS and/or
LC/MS methods are used as the primary method(s) to generate study data.
5. With respect to TCPSA matrix interferences in ground water, the reviewer noted that the
study author quantified the residues in the controls as
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
8. The reported limit of quantitation (LOQ) was determined as the lowest level of method
validation (LLMV). This means that the concentrations can reliably quantified at the LOQ
(i.e., LLMV), but whether lower concentrations may also be reliably quantified is uncertain,
(pp. 29-30, 35-38 of MRID 50432501; p. 11 of MRID 50352202). IntheECM, the LOQ
was defined as the lowest fortification level, and blank values should not be >30% of the
LOQ; no calculations or comparisons to background levels were reported to justify the LOQ
for the method in the ECM. In the ILV, the LOQ was reported from the ECM without
justification. The LOD was calculated in the ECM using the following equation: LOD =
(3x(SNcti)/(RespLs) x ConcLS , where, LOD is the limit of detection of the analysis, SNcti is
the mean signal to noise in height of the control samples (or Blanks), RespLS is the mean
response in height of the two low calibration standards, and ConcLS is the concentration of
the low calibration standard.
The reviewer noted that the LOD for the confirmation analysis of TCPSA in surface water
was >LOQ, 0.103 |ig/L (p. 31 of MRID 50432501). Further work could have been done to
explore the actual LOQ.
9. It was reported for the ILV that one sample set of 13 samples required ca. 3 working days)
including LC/MS/MS analysis time (Appendix VI, p. 109 of MRID 50352202).
V. References
U.S. Environmental Protection Agency. 2012. Ecological Effects Test Guidelines, OCSPP
850.6100, Environmental Chemistry Methods and Associated Independent Laboratory
Validation. Office of Chemical Safety and Pollution Prevention, Washington, DC. EPA 712-
C-001.
USEPA.2014. Registration Review Problem Formulation for Triallate. DP barcode 437990. U.S.
Environmental Protection Agency, Office of Chemical Safety and Pollution Prevention,
Environmental Fate and Effects Division. Memorandum to the Pesticide Re-Evaluation
Division. Aug. 21, 2014.
40 CFR Part 136. Appendix B. Definition and Procedure for the Determination of the Method
Detection Limit-Revision 1.11, pp. 317-319.
Page 10 of 11
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Triallate (PC 078802)
MRIDs 50432501 / 50352202
DER Attachment 1: Chemical Names and Structures
Triallate
IUPAC Name:
CAS Name:
CAS Number:
SMILES String:
TCPSA
IUPAC Name:
CAS Name:
CAS Number:
SMILES String:
Page 11 of 11
S-2,3,3-Trichloroallyl diisopropyl(thiocarbamate)
S-(2,3,3 -trichloro-2-propen-1 -yl) N,N-bis( 1 -m ethyl ethyl)carbamothioate
2303-17-5
CC(C)N(C(C)C)C(=0)SCC(C1)=C(C1)C1
ch3 o ci
JL Cl
h3c^ ch3
Sodium 2,3,3-trichloro-2-propene-l-sulfonate
Not reported
Not reported
Not found
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