Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; 0423718 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

MEMORANDUM 

Date: 12-November-2014 

OFFICE OF CHEMICAL SAFETY AND 

POLLUTION PREVENTION 

Subject: Azoxystrobin. Petition for the Establishment of Permanent Tolerances on Imported 

Pear, Imported Tea, and Imported Coffee. Petition for the Establishment of 

Permanent Tolerance on Ti Palm and for Crop Group Conversions for Stone Fruit 

Group 12-12 and Tree Nut Group 14-12. Summary of Analytical Chemistry and 

Residue Data. 

From: 

PCCode: 128810 

Decision No.:486446, 4qs1t./'l 

Petition No.: 3E8228; 4E83 I 9 

Risk Assessment Type: NA 

TXR No.: NA 

MRID No.: See Below 

Steve Funk, Senior Chemist 

Risk Assessment Branch III (RABIII) 

Health Effects Division (HED; 7509P) 

DP Barcode: D423334; D423718 

Registration No.: NIA 

Regulatory Action: Tolerance Petition 

Case No.: NIA 

CASNo.: 131860-33-8 

40CFR§180.507 

Through: Christine Olinger, Branch Chief ~ ,/;~ · ' 

Risk Assessment Branch III (RABIII) ~ ~ · 

Health Effects Division (HED; 7509P) 

To: Shaunta Hill/Shaja Joyner, RM#20 

Fungicide Branch 

Registration Division (7505P) 

Note: The DERs were originally prepared under contract by Versar, lnc. (6850 Versar Center, Springfield, VA 

22151; submitted 5123112). The document has been reviewed by the Health Effects Division (HED) and revised to 

reflect current Office of Pesticide Programs (OPP). 

Page 1 of 25 
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode 0423334; 0423718 

OCSPP 860 MRID Number Title 

Series 

Guideline 

860. 1500 49227501 C. Ellis, 2013, Azoxystrobin - Residue Study on Pears in 

South Korea in 2012, S 12-03087,Unpuslished study prepared by Eurofins 

Agro Science Services, Ltd., 134 p (A I 29 I 3A 50000) 

860.1500 49227502 N. Smith,, 2013, Azoxystrobin SC (Al3364A}- Compilation of 

Residue Data in or on Tea, TKO 185024, Unpublished study prepared by 

Syngenta Crop Protection, LLC, 110 p. (Al 3364A 50000) 

860.1500 49227503 K. Mickelson, 2012, Azoxystrobin and Cyproconazole (Al2910C) 

860.1520 - Magnitude of the Residues in or on Coffee: Final Report, TK0046957, 

67650, unpublished study prepared by International Agricultural 

Research, Inc., Morse Laboratories, Inc., 381 p. (A 1291 OC 50005) 

Page 2of25 
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 3 of 25

Table of Contents

1.0 Executive Summary............................................................................................................ 5

2.0 Regulatory Recommendations............................................................................................ 5

2.1 Data Deficiencies/Data Needs.......................................................................................... 5

2.2 Tolerance Considerations................................................................................................. 5

2.2.1 Enforcement Analytical Method............................................................................... 6

2.2.2 Recommended Tolerances........................................................................................ 6

2.2.3 Revisions to Petitioned-For Tolerances.................................................................... 7

2.2.4 International Harmonization ..................................................................................... 7

3.0 Introduction......................................................................................................................... 7

3.1 Chemical Identity ............................................................................................................. 8

3.2 Physical/Chemical Characteristics................................................................................... 8

3.3 Pesticide Use Pattern/Directions for Use (860.1200)....................................................... 9

4.0 Metabolite/Degradate Residue Profile.............................................................................. 10

4.1 Nature of the Residue..................................................................................................... 10

4.1.1 Summary of Plant Metabolism (860.1300)............................................................. 11

4.1.2 Summary of Livestock Metabolism (860.1300)..................................................... 11

4.1.3 Summary of Confined Rotational Crops (860.l850)............................................... 11

5.0 Residue Profile.................................................................................................................. 11

5.1 Residue Analytical Methods (860.1340)........................................................................ 11

5.1.1 Data Collection Methods ........................................................................................ 12

5.1.2 Multi-Residue Methods (860.1360)........................................................................ 12

5.1.3 Tolerance Enforcement Methods............................................................................ 13

5.1.4 Submittal of Analytical Reference Standards (860.1650) ...................................... 13

5.2 Storage Stability (860.1380) .......................................................................................... 13

5.3 Residue Data .................................................................................................................. 15

5.3.1 Crop Field Trials (860.1500) .................................................................................. 15

5.3.2 Field Rotational Crops (860.1900) ......................................................................... 17

5.3.3 Processed Food and Feed (860.1520)..................................................................... 17

5.3.4 Meat, Milk, Poultry and Eggs (860.1480) .............................................................. 18

5.3.4.1 Dietary Burden ................................................................................................ 19

5.3.4.2 Estimated Secondary Residues in Livestock ................................................... 19

5.3.5. Food Handling (860.1460)...................................................................................... 19
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 4 of 25

5.3.6 Water, Fish, and Irrigated Crops (860.1400).......................................................... 19

6.0 Tolerance Derivation ........................................................................................................ 19

Appendix A. International Residue Limits Table ........................................................................ 21

Appendix B. OECD MRL Calculation Procedure Inputs/Outputs.............................................. 22

 
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 5 of 25

1.0 Executive Summary

Axoxystrobin fungicide is currently registered for use on a variety of field, vegetable, fruit, and 

nut crops as well as on ornamental plants and turf. End-use products of azoxystrobin are 

typically formulated as water dispersible granular (WDG), suspension concentrate (SC; 

previously referenced as flowable concentrate), and soluble emulsion (SE) formulations. These 

products may be applied as in-furrow at-planting or postemergence foliar applications using 

ground or aerial equipment at maximum seasonal rates of 0.40-2.0 lb ai/A. Azoxystrobin is also 

registered for seed treatment of many food/feed crops as well as for postharvest uses on 

bananas/plantains and citrus fruits.

The residue chemistry data base is adequate. The nature of the residue in plants, rotational crops, 

and livestock is adequately understood. Acceptable metabolism studies have been conducted on 

primary crops of grapes, peanuts, and wheat as well as on representative rotational crops. 

Acceptable metabolism studies on goats and laying hens are also available. The residues of 

concern in/on primary and rotational crop commodities, for tolerance expression and risk 

assessment purposes, are azoxystrobin and its Z-isomer (R230310). The residue of concern in 

livestock is parent azoxystrobin only. There are adequate existing storage stability data to 

validate the storage conditions and durations of samples from the submitted studies. 

The current proposal (3E8228) from Syngenta Crop Protection is for import tolerances with no 

domestic registrations (uses) for tea, coffee, and pear. Relevant crop field trial studies from nonUS locations and specimen labels were supplied in support of the tolerance requests. A coffee 

processing study was also submitted.

Additionally, IR4 has petitioned (4E8321) to establish a tolerance for Ti palm based on the 

existing data for crop subgroup 1A and crop subgroup 2 and has petitioned for conversion of the 

stone fruit crop group to 12-12 and the tree nut group to 14-12. No new data were submitted.

2.0 Regulatory Recommendations

There are no residue chemistry considerations that would preclude establishing the 

recommended tolerances for azoxystrobin on pear, coffee, and tea. All are for import tolerances 

with no domestic registrations. Additionally, there are no residue chemistry consideration that 

would preclude establishing the recommended tolerance for Ti palm and establishing the crop 

group conversions for stone fruit group 12-12 and tree nut group 14-12. The specific tolerance 

recommendations are discussed in Section 2.2.

2.1 Data Deficiencies/Data Needs

None.

2.2 Tolerance Considerations
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 6 of 25

2.2.1 Enforcement Analytical Method

PP#s 5F4541 & 6F4762; DP# 235342, 5/30/97, C. Stafford

PP#7F4864; DP#s 249657 and 249668, 1/25/99, D. Dotson 

PP#s 6F7106 & 7F7198; DP#s 334571 & 340016, 3/12/08, W. Cutchin

PP#5F4541; DP#s 218318 and 218448, 3/19/96, J. Garbus 

A GC/NPD method, RAM 243/04, is available for the enforcement of tolerances for residues of 

azoxystrobin and its Z-isomer in crop commodities. The method has undergone method 

validation by the Analytical Chemistry Branch (ACB)/Biological and Economic Analysis 

Division (BEAD). The method was revised to incorporate comments made by BEAD, and the 

revised method (designated RAM 243, dated 5/15/98) has been submitted to FDA for inclusion 

in Pesticide Analytical Manual (PAM), Volume II. The LOQ is 0.01 ppm for each analyte in 

crop commodities.

Data have previously been submitted pertaining to the multiresidue methods testing of 

azoxystrobin in conjunction with the grape petition (PP#5F4541). The data indicate that 

azoxystrobin could not be recovered through application of the multiresidue protocols. These 

data have been forwarded to FDA for inclusion in PAM I.

Azoxystrobin may be determined by QuEChERS. 

2.2.2 Recommended Tolerances

The residue definition (40CFR§180.507) complies with the recommendation of the S. Knizner 

5/27/09 memo. No change is needed. For compliance in plant commodities, the sum of 

azoxystrobin and its Z-isomer is determined.

Table 2.2.2. Tolerance Summary for Azoxystrobin

Commodity Proposed Tolerance 

(ppm)

HED-Recommended 

Tolerance (ppm)

Comments 

(correct commodity definition)

Coffee, bean, green 0.03 0.03 Coffee, green bean

Asian Pear 0.07 0.07 Pear, Asian

Tea 10.0 20.0 Tea, dried 

Ti palm, leaves 50 50.0 Ti, leaves

Translation of existing group 2 

(leaves of root and tuber 

vegetables) tolerance. 

Ti palm, roots 0.5 0.5 Ti, roots

Translation of existing subgroup 

1A (root vegetable) tolerance.

Stone Fruit Group 12 Revoke Revoke Crop Group conversion to 12-12

Fruit, Stone, Group 12-

12

2.0 2.0 Crop Group conversion.

Harmonization with Codex.

Nut, Tree, Group 14 Revoke Revoke Crop Group conversion to 14-12

Nut, tree, group 14-12 0.02 0.02 Nut, tree, group 14-12, except 

pistachio.

Crop Group conversion. 

Pistachio remains at a higher 

tolerance (0.50 ppm)
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 7 of 25

2.2.3 Revisions to Petitioned-For Tolerances

The proposed tolerance of 10.0 ppm for tea is insufficient, as the trials were conducted at 50% of 

the label maximum rate. Correction by proportionality to the maximum label rate provides a 

tolerance recommendation of 20 ppm.

2.2.4 International Harmonization

The residue definitions for plants and livestock are not harmonized with Codex; the US and the 

Canadian residue definitions include both the predominant E isomer and the minor Z isomer

whereas the Codex includes only the E isomer.

A Codex MRL has been established for coffee beans at 0.03 mg/kg, but no MRLs have been 

established for pear or tea. Codex recommended an increase in its coffee bean tolerance from 

0.02 to 0.03 ppm in 2013. The recommended US tolerance for coffee is harmonized with Codex. 

No MRLs have been established in Canada for tea, coffee, or pears. The International Residue 

Limits (IRL) table is found in Appendix A.

Codex has not established an MRL for ti palm leaves or roots. Canada has not established a 

tolerance for ti palm leaves or roots. There is no issue of harmonization. 

For the crop group conversions, Codex has established an MRL for stone fruit at 2 mg/kg. 

Canada has a tolerance for peach at 0.8 ppm. For purposes of harmonization with Codex, the 

stone fruit group 12-12 will be increased to 2.0 ppm from the current tolerance of 1.5 ppm for 

stone fruit group 12.

Codex has established an MRL of 0.01 mg/kg for tree nuts. Canada has established tolerances of 

0.02 ppm for the various tree nuts, which is harmonized with the US. The US crop group 

tolerance is based on a residue definition of azoxystrobin plus the z-isomer (R230310). Residues

were <0.01 ppm for each component in the almond and pecan trials. Therefore, the tolerance 

estimate is 0.02 ppm, the sum of the components. The Codex residue definition is parent only, 

which support the 0.01 mg/kg MRL. The US tolerance cannot be harmonized with Codex.

2.3 Label Recommendations

There are no domestic uses proposed for coffee, tea, or pear and therefore no domestic labels. 

Adequate summaries of appropriate foreign labels were provided. A proposed master label was 

provided for ti palm and for the stone fruit group and tree nut group conversions. No changes to 

the proposed label are needed.

3.0 Introduction

Azoxystrobin is a broad-spectrum fungicide and belongs to a class of pesticidal compounds 

called β-methoxyacrylates, which are derived from the naturally occurring strobilurins (Group 11 

fungicide). The biochemical mode of action is inhibition of electron transport. 
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 8 of 25

3.1 Chemical Identity

Table 3.1. Azoxystrobin Nomenclature.

Compound

Common name Azoxystrobin

Company experimental name ICIA5504 (Zeneca), R215504 (Syngenta)

IUPAC name methyl (2E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-

methoxyacrylate

CAS name methyl (αE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)-

benzeneacetate

CAS registry number 131860-33-8

End-use products (EP) None for current petition.

Regulated metabolite, Zisomer

Common name Azoxystrobin, Z-isomer

Company experimental name R230310

Chemical name methyl (2Z)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-

methoxyacrylate

3.2 Physical/Chemical Characteristics

N N

O O

CN OCH3

O

H3CO

N N

O O

CN

O OCH3

H3CO
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 9 of 25

Table 3.2. Physicochemical Properties of Technical Grade Azoxystrobin.

Parameter Value Reference

Melting point/range 114-116oC DP#s 218318 and 218448, 

3/19/96, J. Garbus pH 6.4

Density 1.25 g/cm3

Water solubility (20°C) pH 5.2 6.7 mg/L

pH 7.0 6.7 mg/L

pH 9.2 5.9 mg/L

Solvent solubility (20°C) Hexane 0.057 mg/L

Octanol 1.4 mg/L

Methanol 20 mg/L

Toluene 55 mg/L

Acetone 86 mg/L

Ethyl Acetate 130 mg/L

Acetonitrile 340 mg/L

Dichloromethane 400 mg/L

Vapor pressure (20°C) 1.1x10-13 kPa (8.2x10-13 mm Hg)

Dissociation constant, pKa Not dissociable

Octanol/water partition coefficient, 

Log(KOW)

log P = 2.5

3.3 Pesticide Use Pattern/Directions for Use (860.1200)

Table 3.3. Summary of Proposed Directions for Use of ChemicalName1.

Applic. 

Timing, Type, 

and Equip.

Formulation

Applic. 

Rate 

g ai/ha

[lb 

ai/acre]

Max. No. 

Applic. per 

Season

Max. Seasonal 

Applic. Rate

g ai/ha

[lb ai/A]

PHI

(days)

Use Directions and 

Limitations

Coffee

Foliar with 

ground 

equipment.

AmistarZtra

SC

(200 g/L 

azoxystrobin;

80 g/L

Cyproconazole)

Colombia

100-150

[0.089-

0.14]

3

4502

[0.40]

15

Start application 90 days 

after principal flowering 

followed by 2 

consecutive applications 

with a 45 day interval. 

Use a mixture volume of 

50 cc per tree after 

diluting 1.8 ml of 

commercial product to 1 

liter of water. Apply 

when the coffee crop 

(leaves, branches, and 

fruits) is dry. The 

reentry interval is 4 

hours.

Asian Pear

Foliar

Azoxystrobin Amistar 

WP 10%

(South 

Korea)

4503

[0.40] 5

2250

[2.0] 7

Apply at beginning of 

infestation with a 10 day 

retreatment interval.
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 10 of 25

Tea

Foliar

Amistar 20 

SC

(0.22 kg/L)

4

110– 440

[0.098-

0.39]

3

1320

[1.17]

14

Dilution rate 1 g product 

per 1 L water. Apply 

mixture at a maximum 

of 4000 L/ha.

Ti Palm

Foliar

Abound 

Flowable

(reg no 100-

1098)

(2.08 lb/gal)

112-370

[0.10-

0.33]

Not 

specified

2240

[2.00] 0

Soil

Abound 

Flowable

(reg no 100-

1098)

(2.08 lb/gal)

0.0065-

0.013 lb 

ai/1000 

row feet

Not 

specified

2240

[2.00] 0

Band application 

between rows.

Use for 

soilborne/seedling 

disease control.

Apply in a minimum of 

10 gallons per acre

1Based on foreign label translations provided in Section B of the petition. There are no domestic registrations for 

the proposed new uses on coffee, pear, and tea.

2Calculated based on a maximum of 8333 trees per ha.

31 g product is diluted to 1 liter. Calculated from an application of 4500 liters spray solution per ha.

4Density 1.1 g/cm3

.

Conclusions. 

Label translations provided as Section B of the petition are adequate to allow evaluation of the 

residue data relative to the proposed use. For the foreign uses (pear, coffee, tea), label 

deficiencies are not addressed. 

For the crop group conversions (stone fruit, tree nuts), the master label (registration number 100-

1098) is acceptable. The list of stone fruits and tree nuts included in the new groups have been 

correctly provided. The use directions remain unchanged. For Ti palm, the proposed label is 

adequate, and there are no deficiencies.

4.0 Metabolite/Degradate Residue Profile

4.1 Nature of the Residue

Table 4.0. Summary of Metabolites and Degradates to be included in the Risk Assessment and 

Tolerance Expression for Azoxystrobin1

Matrix Residues included in Risk 

Assessment

Residues included in Tolerance 

Expression

Plants Primary Crop Azoxystrobin + Z-isomer Azoxystrobin + Z-isomer

Rotational Crop Azoxystrobin + Z-isomer Azoxystrobin + Z-isomer

Livestock Ruminant Azoxystrobin Azoxystrobin

Poultry Azoxystrobin Azoxystrobin

Drinking Water Azoxystrobin Not Applicable

1 HED Metabolism Assessment Review Committee Decision Memo; DP# 251683, 12/30/98, W. Wassell
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 11 of 25

4.1.1 Summary of Plant Metabolism (860.1300)

PP#5F4541; DP#s 218318 and 218448, 3/19/96, J. Garbus 

PP#6F4762; DP#s 230634, 230635, 230636, and 230637; 4/25/97; L. Kutney 

Adequate metabolism studies on grapes, peanuts, and wheat were submitted in conjunction with 

earlier azoxystrobin petitions, PP#s 5F4541 and 6F4762. Azoxystrobin undergoes 

photochemical isomerization to produce the Z-isomer and is extensively metabolized in plants. 

The parent compound undergoes cleavage of the ether linkages between the phenylacrylate and 

pyrimidinyl rings and the cyanophenyl and pyrimidinyl rings, with subsequent oxidation, 

hydrolysis, and/or reduction of the primary metabolites to form numerous secondary metabolites. 

Azoxystrobin is systemic. HED has determined that the residues of concern in/on plants for 

tolerance expression and risk assessment purposes are azoxystrobin and its Z-isomer.

4.1.2 Summary of Livestock Metabolism (860.1300)

PP#5F4541; DP#s 218318 and 218448, 3/19/96, J. Garbus 

PP#6F4762; DP#s 230634, 230635, 230636, and 230637; 4/25/97; L. Kutney 

HED Metabolism Assessment Review Committee Decision Memo; DP# 251683, 12/30/98, W. Wassell

The nature of the residue in livestock is adequately understood based on acceptable metabolism 

studies conducted on goats and laying hens. HED has determined that the residue of concern in 

livestock is parent azoxystrobin only. 

Note that this topic is not relevant to the current submission, as pears, tea, and coffee do not have 

livestock feed items. Ti palm roots/leaves are not recognized as significant feed items.

4.1.3 Summary of Confined Rotational Crops (860.l850)

PP#6F4762; DP#s 230634, 230635, 230636, and 230637, L. Kutney, 4/25/97

PP#9F6058; DP# 260134, 9/6/00, M. Nelson 

Adequate confined studies have previously been presented in PP#6F4762 and re-evaluated in 

PP#9F6058. Azoxystrobin is metabolized via four pathways: (i) hydrolysis of the ester, followed 

by conjugation to glucose or malonylglucose; (ii) reduction of the side chain double bond 

followed by conjugation to glucose or malonylglucose; (iii) cleavage of the ether linkage to form 

two-ring compounds followed by further conjugation; and (iv) mineralization to 14C-carbon 

dioxide which is incorporated into natural products. Rotational crops were found to contain a 

larger amount of conjugated metabolites than found in the primary crop metabolism studies, and 

these conjugated metabolites were conjugates of primary crop metabolites

HED has concluded that the residues of concern in rotational crops are parent and the Z-isomer.

Note that this topic is not relevant to the current requests for import tolerances. 

5.0 Residue Profile

5.1 Residue Analytical Methods (860.1340)
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 12 of 25

5.1.1 Data Collection Methods

49227501.der

49227502.der

49227503.der

For pear and coffee, samples were analyzed for residues of azoxystrobin and its Z-isomer 

(R23010) using a standard high performance liquid chromatography method with tandem mass 

spectrometry detection (LC/MS/MS), Method RAM 305/03. Samples were extracted twice with 

acetonitrile (ACN):water (90:10, v:v). After centrifugation, the combined extracts were cleaned 

up on a C18 solid phase extraction (SPE) column for analysis. Transitions monitored were 

404.1/372.1 and 404.1/344.0. Matrix matched standards were used. Acceptable concurrent 

recoveries were reported for pear samples at fortification levels of 0.01 and 0.10 ppm (90-112% 

azoxystrobin, 84-91% Z-isomer), thus validating the method. Acceptable method validation and 

concurrent recoveries were reported for green coffee bean samples at fortification levels of 0.01 

and 1.0 ppm (87-116% azoxystrobin, 89-118% Z-isomer), thus validating the method. The limit 

of quantitation (LOQ; determined as the lowest level of method validation, LLMV) was 0.01 

ppm for each analyte; the LOQ for combined residues was 0.02 ppm, for both coffee beans and 

pear fruits. 

For tea, non-standard high performance liquid chromatography methods with UV detection 

(HPLC/UV 235nm) were used at two different laboratories. Samples were extracted with organic 

solvent, concentrated, and purified by sequential solid-phase extractions (SPE). The final eluates

were concentrated to dryness and redissolved in ACN:water (1:1, v:v) for HPLC/UV analysis. 

Acceptable concurrent recoveries were reported for tea samples fortified with azoxystrobin and 

its Z-isomer (R230310) at 0.4 ppm each (JACC location; 82-92%) and with azoxystrobin at 1.6 

ppm (92-101%) and 10 ppm (JFRL location), thus validating the methods. Samples were 

analyzed for only azoxystrobin. The LOQ was 0.4 ppm or 1.6 ppm, depending on the laboratory.

Conclusions.

Method RAM 305/03 has been adequately validated as a data collection method for coffee and 

pears. This method has been used previously for data collection (D397692, M. Negussie, 

03/21/2013). The HPLC/UV method for tea was validated at relatively high concentrations and 

was not used to determine the Z-isomer. 

5.1.2 Multi-Residue Methods (860.1360)

PP#5F4541; DP#s 218318 and 218448, 3/19/96, J. Garbus 

Data have previously been submitted pertaining to the multiresidue methods testing of 

azoxystrobin in conjunction with the grape petition (PP#5F4541). The data indicate that 

azoxystrobin could not be recovered through application of the multiresidue protocols. These 

data have been forwarded to FDA for inclusion in PAM I.

Azoxystrobin may be determined by QuEChERS. Adequate recoveries and precision have been 

demonstrated for acidic, dry (cereal), sugar containing, and water containing matrices at 

fortifications of 0.01 to 0.25 ppm (DIN EN 15662 (2009-02); Foods of plant origin -
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 13 of 25

Determination of pesticide residues using GC-MS and/or LC-MS/MS following acetonitrile 

extraction/partitioning and clean-up by dispersive SPE - QuEChERS-method).

Conclusions. 

US FDA MRMs are not suitable for the determination of azoxystrobin.

5.1.3 Tolerance Enforcement Methods

PP#s 5F4541 & 6F4762; DP# 235342, 5/30/97, C. Stafford

PP#7F4864; DP#s 249657 and 249668, 1/25/99, D. Dotson 

PP#s 6F7106 & 7F7198; DP#s 334571 & 340016, 3/12/08, W. Cutchin

Crop commodities: A GC/NPD method, RAM 243/04, is available for the enforcement of 

tolerances for residues of azoxystrobin and its Z-isomer in crop commodities. The method has 

undergone method validation by the Analytical Chemistry Branch (ACB)/Biological and 

Economic Analysis Division (BEAD). The method was revised to incorporate comments made 

by BEAD, and the revised method (designated RAM 243, dated 5/15/98) has been submitted to 

FDA for inclusion in Pesticide Analytical Manual (PAM), Volume II. The LOQ is 0.01 ppm for 

each analyte in crop commodities.

Conclusions.

An adequate residue analytical method is available for tolerance enforcement in crop 

commodities. 

5.1.4 Submittal of Analytical Reference Standards (860.1650)

Reference standards are available from the EPA National Pesticide Standards Repository (Email 

from T. Cole, 10/14/2014). The azoxystrobin standard expires 07/26/2018, and the Z-isomer 

standard expires 08/31/2018.

5.2 Storage Stability (860.1380)

DER References:

48601201.der (including MRID 4860102)

48601203.der

PP#7F4864; DP#s 248887 and 249671, 10/14/98, D. Dotson, et al.

PP#7F4864; DP#s 249657 and 249668, 1/25/99, D. Dotson

Adequate storage stability data are available indicating that azoxystrobin and its Z-isomer are 

reasonably stable under frozen conditions in/on fortified samples of diverse crops. In previous 

studies, residues were determined to be stable for 2 years in/on apple, banana, carrot, cucumber, 

grape, leaf lettuce, rape seed, peach, winter wheat straw, wheat forage, and wine. Over the 2-

year period, residues of both azoxystrobin and its Z-isomer decreased by up to 20% in winter 

wheat grain and by up to 27% (azoxystrobin only) in tomato, peanut, and pecan, but all 

recoveries were >70%; residues in these crops were stable (without decrease) for up to 6-8 

months of storage.
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 14 of 25

Previous studies conducted on processed commodities demonstrated that fortified residues of 

azoxystrobin and its Z-isomer were generally stable under frozen conditions in peanut oil and 

meal, tomato juice and paste, and wheat bran for up to 1 year, and in soybean meal, corn grits, 

and orange oil, juice and pulp for at least two years.

A concurrent storage stability was conducted to support the tea field trial study. Control samples 

of each commodity were fortified with azoxystrobin or the Z-isomer and placed in storage under 

the same frozen conditions as the treated samples for the same storage durations; no 0-day data 

were provided. 

Table 5.2.1. Stability of Azoxystrobin In Tea Leaves Following Storage at -20oC

Commodity Spike 

level 

(ppm)

Storage interval

(days)

Recovered 

residues

(%)

Mean 

Recovered 

Residues

(%)

Corrected % 

recovery

Azoxystrobin

Dried tea leaves 1.0 67 93.3, 92.2 92.8 106

76 80.8, 76.3 78.6 87.0

83 90.3, 88.6 89.7 105

83 74.7, 74.0 74.4 96.4

2 108 89, 88 88 91

119 84,83 84 87

122 84, 83 84 87

122 94,92 93 96

Z-Isomer (R230310)

Dried tea leaves 1.0 67 95.8, 95.6 95.7 114

76 80.7, 79.8 80.2 101

83 95.2, 93.6 94.4 116

83 74.7, 74.0 74.4 96.4

Table B.5.2.2. Summary of Storage Conditions.

Matrix Storage Temperature 

(°C)

Actual Storage Duration1Interval of Demonstrated Storage Stability

Pear ≤-18 42-66 days

(1.4-2.2 months)

Residues of azoxystrobin and R230310 are stable 

for up to 2 years in various crops including apples 

stored frozen (<-18 °C).2

Tea, Dried 

Leaves

-20 79 – 113 days

(2.6 – 3.7 months)

Azoxystrobin is stable for up to 4.0 months. The Zisomer is stable for up to 3 months. Concurrent 

storage stability (see Table 5.2.1)

Coffee, green 

beans

-20 31-57 days

(1.0-1.9 months)

71 days (2.6 months) beans 

for processing

Residues of azoxystrobin and R230310 are stable 

for up to 2 years in various crops including oil seed 

rape stored frozen (<-18 °C).2

Coffee, dry 

roasted bean

-20 28 days (0.9 months)

Coffee, instant -20 21 days (0.7 month)

1

Interval from harvest to analysis. The petitioner indicated samples were analyzed within 7 days of extraction for pear, 0-3 days 

for coffee. Extraction dates not provided for tea.

2 DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98

.

Conclusions
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 15 of 25

The storage stability data are adequate to support the field trials and coffee processing study. 

Stability for up to two years of frozen storage has been demonstrated for high water (lettuce, 

apple), high acid (orange), high oil (rape seed), and high starch (wheat) commodities. Stability 

has not been demonstrated in a high protein commodity (such as pulses).

5.3 Residue Data

5.3.1 Crop Field Trials (860.1500)

49227501.der

49227502.der

49227503.der1

Asian Pear

Syngenta Crop Protection, LLC has submitted field trial data for azoxystrobin on Asian pears. 

Eight pear field trials were conducted in South Korea during the 2012 growing season. All pears 

were contained in paper/wax paper bags according to local practices and regulations for this crop 

in South Korea. The bags were placed on the pears well in advance of the first application and 

remained in place until harvest. Each trial consisted of one untreated plot and one treated plot. 

At all trial locations, the treated plot received five foliar broadcast applications of a 10% wettable 

powder (WP) formulation of azoxystrobin (A12913A) at 0.359-0.475 lb ai/A/application (402-

532 g ai/ha/application) for total rates of 1.978-2.081 lb ai/A (2218-2333 g ai/ha). All 

applications were made at retreatment intervals (RTIs) of 9-11 days using ground equipment in 

spray volumes of 430-568 gal/A (4024-5315 L/ha); no adjuvants were used. At all trials, pears 

were harvested at a 7-day preharvest interval (PHI). 

Tea

Syngenta Crop Protection, LLC has submitted residue data for azoxystrobin on tea. Four tea 

field trials for were conducted in Japan during the 1998 growing season. Each trial consisted of 

one untreated plot and one treated plot divided into three subplots (2, 3, and 4) to establish 

separate preharvest intervals (PHIs). Each treated plot received three foliar spray applications of 

a 20% suspension concentrate (SC) formulation of azoxystrobin (Amistar® 20 SC) at 0.196 lb 

ai/A/application (220 g ai/ha/application), for a total rate of 0.589 lb ai/A (660 g ai/ha). Note 

that this is about 50% of the proposed label application rate, both per application and per season. 

All applications were made at retreatment intervals (RTIs) of 7 days using ground equipment in 

spray volumes of 214 gal/A (2000 L/ha); no adjuvants were used. Single samples of green tea 

leaves were harvested at PHIs of 7, 14, and 21 days from subplots 2, 3, and 4, respectively, and 

were dried. 

Coffee

Syngenta Crop Protection, LLC has submitted residue data for azoxystrobin on coffee from field 

trials conducted in Central and South America. Four coffee field trials were conducted during 

the 2011 and 2012 growing seasons in Colombia (1 trial), Guatemala (1 trial), and Brazil (2 

trials). HED has determined that two trials conducted in Colombia are replicate trials; the trial 

count reflects this conclusion. 
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 16 of 25

Each trial consisted of one untreated plot and one treated plot. At all trial locations, the treated 

plot received three foliar spray applications of a 1.67 lb ai/gal (200 g ai/L) suspension 

concentrate (SC) formulation of azoxystrobin (A12910C). The product is a multiple active 

ingredient (MAI) formulation that also contains cyproconazole at 0.67 lb ai/gal (80 g ai/L). Each 

treated plot received three applications of azoxystrobin at 0.131-0.137 lb ai/A/application (146.7-

154.0 g ai/ha/application) for total rates of 0.394-0.410 lb ai/A (441.7-459.3 g ai/ha). All 

applications were made at retreatment intervals (RTIs) of 42-49 days using ground equipment in 

spray volumes of 21.38-42.58 gal/A (200.0-398.3 L/ha). A nonionic surfactant (NIS) alone or in 

conjunction with a crop oil was added to the spray mixtures for all applications. Samples of 

coffee bean “cherries” were harvested from all trials at a 14- to 15-day preharvest interval (PHI). 

Ti

IR-4 has petitioned to establish tolerances for ti palm leaves and ti palm roots. No field trial data 

were submitted in support of the request. It is proposed to translate the root vegetable subgroup 

1A tolerance to ti root and the leaves of root and tuber vegetables group 2 tolerance to ti leaves. 

ChemSAC (ChemSAC Minutes, 06/11/2013) approved the proposal based on the following 

rationale:

Ti palm parts consumed are roots and tops (leaves). Ti palm is being considered for inclusion into Root and tuber vegetable 

group 1, and crop subgroups 1A Root vegetable and 1B Root vegetable, except sugar beet subgroup, as well as crop group 2 

leaves of root and tuber group. Ti palm is a very minor crop with low dietary intake and its roots are consumed in human diets 

and the leaves are used to wrap food items.... 

The proposed use patterns on ti palm are identical to the existing use pattern, both foliar and soil 

application, for carrot, potato, and other root crops. ChemSAC noted that a similar request was 

approved previously for propiconazole.

Table 5.3.1. Summary of Residues from Field Trials with Azoxystrobin

Crop 

Matrix Analyte

Applic. 

Rate

(lb 

ai/acre)

[g ai/ha]

PHI 

(days) n

*

Residues (ppm)

Min.† Max.† LAFT* HAFT* Median* Mean* SD*

Pear Proposed Use = 2 lb ai/acre total application rate, 7-day PHI.

Pear 

(bagged)

Azoxystrobin 

+ Zisomer

1.978-

2.081

[2218-

2333]

7 8 <0.02 <0.05

(0.041)

<0.02 <0.05

(0.041)

0.02 0.03 0.01

Tea Proposed Use =1.2 lb ai/acre total application rate, 14-day PHI.

Tea, dried Azoxystrobin

0.589

[660]

14 4 0.69 4.66 0.69 4.66 2.80 2.74 1.67

Coffee Proposed Use =1.2 lb ai/acre total application rate, 14-day PHI

Coffee, 

green bean

Azoxystrobin 

+ Zisomer

0.394-

0.410

[441.7-

459.3]

14-15 4 <0.02 <0.0259

(0.0161)

<0.02 <0.0230 0.0202 0.0209 0.0014

† Values based on total number of samples.

* Values based on per-trial averages. LAFT = Lowest Average Field Trial, HAFT = Highest Average Field Trial, SD = Standard 
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 17 of 25

Deviation. For computation of the LAFT, HAFT, median, mean, and standard deviation, values < LOQ are assumed to be at the 

LOQ, or 0.01 ppm for each of azoxystrobin and its Z-isomer.

1Azoxystrobin only.

Conclusions. 

The coffee and pear field trials reflect the proposed use patterns, and the number of independent 

field trial meet at the minimum number of trial requirements for import purposes. Brazil is a 

major exporter of coffee to the US, and 4 trials is 80% of the number of trials recommended for 

coffee (OSCPP 860.1500). Pear is not a major import from South Korea, and the use (bagged 

fruit) is unique. All pears exported to the US are treated while bagged, in accordance with South 

Korea regulation. Eight trials is 100% of the number of trials required for a domestic tolerance. 

Japan is not a major exporter of tea to the US, but the pesticide is not registered for use on tea in 

major exporting countries such as China and India (S. Hill, PRIA 3 Technical Screen, 

04/24/2014 Email). The number of required trials for US (domestic) tolerance is not specified. 

Four trials is considered adequate. The tea trials were conducted at about 50% of the proposed 

label rate for each of the three applications. Proportionality may be used to adjust the residue 

values. The analytical methods are adequate for data collection purposes. However, the tea 

samples were not analyzed for the Z-isomer. This component is anticipated to be <10% of the 

total residue, based on field trial results for other commodities. Samples from all studies were 

stored frozen for intervals of known stability of azoxystrobin and Z-isomer in/on various 

commodities.

No trials were conducted for ti palm, but the root and leaf commodities may be included under 

crop subgroup 1A and crop group 2, respectively. The proposed use pattern for ti palm is 

identical to the existing GAP for potato, carrot, and other root crops.

5.3.2 Field Rotational Crops (860.1900)

This topic is not applicable to the import tolerance requests for tea, pear, and coffee. The plant 

back interval of 0 days established for all crops with azoxystrobin registered uses, except 

buckwheat and millet, applies to the rotation of crops into fields of ti palm treated with 

azoxystrobin.

5.3.3 Processed Food and Feed (860.1520)

49227503.der2

A processing study was provided for coffee. A processing study was not provided for tea. Asian 

pear does not have recognized processed food or feed items. In coffee one trial conducted in 

Guatemala during the 2011 growing season, a treated plot received three foliar spray applications 

of a 1.67 lb ai/gal (200 g ai/L) suspension concentrate (SC) formulation of azoxystrobin 

(A12910C). The treated plot received three applications of azoxystrobin at an exaggerated rate 

of 0.6651-0.6794 lb ai/A/application (745.6-761.7 g ai/ha/application) for a total rate of 2.014 lb 

ai/A (2258 g ai/ha). The application rate used in the study was ~5x that used in the 

corresponding field trials. Samples of coffee bean “cherries” were harvested at a 14-day 

preharvest interval (PHI). Coffee cherries were processed into green coffee beans at the field 
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 18 of 25

sites, and the green coffee bean samples were processed into roasted coffee beans and instant 

coffee at GLP Technologies (Navasota, TX) using simulated commercial practices. Adequate 

descriptions of the processing procedures were provided, including material balance summaries.

Table 5.3.3.1. Residue Data from the Coffee Processing Study with Azoxystrobin

RAC Processed 

Commodity

Total Rate

lb ai/A

(g ai/ha)

PHI

(day)

Residues (ppm) Processing Factor

AzoxystrobinZ-isomer

(R230310)

AzoxystrobinZ-isomer

(R230310)

Coffee

RAC 

(prior to 

processing)

2.014

(2258) 14

<0.01 <0.01 - -

Dry roasted 

coffee <0.0108 <0.01 ~1.1x1 NC2

Instant Coffee <0.0168 <0.01 ~1.7x1 NC2

1Azoxystrobin residues were <LOQ on the RAC, and residues were slightly above the LOQ in one of two replicate 

samples for the processed commodities (0.0115 ppm for dry roasted coffee and 0.0236 ppm for instant coffee).

2Not calculated. Residues were <LOQ in both the RAC and processed fractions for the Z-isomer

A processing study was not conducted for the conversion of the raw agricultural commodity 

(RAC) tea leaves to instant tea. However, the commercial processing of coffee to instant coffee 

is very similar to the commercial processing of tea to instant tea. Both consist of water 

extraction of the RAC and removal of water from the extract by freeze drying or spray drying. 

The percent solids obtained from dried coffee bean and dried tea leaf are similar, approximately 

40% vs 50% (P. Kaleniaa, National Coffee Association USA, Coffee Extract Solids, 2007; US 

Patent 4668525, Thomas J. Lipton, Inc., 1982). The processing factor for instant coffee may be 

translated to instant tea for azoxystrobin. 

Conclusions. 

The coffee processing data are supported by adequate storage stability, and the analytical method 

is adequate for data collection purposes. The residue of concern, azoxystrobin plus Z-isomer, 

was determined for the RAC and processed fractions. A 5X exaggerated rate trial indicated no 

residues at or above the LOQ. Therefore, a processing study is not required. A processing study 

was conducted nonetheless on a RAC having no quantifiable residues. Residues of azoxystrobin, 

but not the Z-isomer, concentrated slightly in one of two replicates for each of instant coffee and 

roasted beans. 

As the preparation processes are very similar and the percentages of solids extracted similar, the 

coffee to instant coffee processing factor results may be translated to the conversion of tea to 

instant tea. This applies only to the current situation with azoxystrobin.

5.3.4 Meat, Milk, Poultry and Eggs (860.1480)
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 19 of 25

There are no livestock feed items associated with Asian pear, tea, and coffee beans. Therefore, 

livestock feeding studies are not relevant.

5.3.4.1 Dietary Burden

There are no feed items associated with Asian pear, tea, and coffee beans. Ti palm root and leaf 

are not considered a significant feed item. Therefore, livestock dietary burdens are not changed.

5.3.4.2 Estimated Secondary Residues in Livestock 

The estimated secondary residues in livestock commodities are not changed by the addition of 

import tolerances for Asian pear, tea, and coffee beans.

5.3.5. Food Handling (860.1460)

There are no food handling uses associated with import tolerance requests for Asian pear, tea, 

and coffee beans.

5.3.6 Water, Fish, and Irrigated Crops (860.1400)

There are no water, fish, and irrigated crop uses/issues associated with import tolerance requests.

6.0 Tolerance Derivation

Recommended tolerance level values were obtained by use of the Organization of Economic 

Cooperation and Development (OECD) calculation procedure. Field trial residue values for pear 

ranged from <LOQ (0.02 ppm) to 0.05 ppm (n = 8, with 5 <LOQ). 

Field trial residue values for coffee were at or below LOQ (0.02 ppm), with a maximum value of 

0.023 ppm. For both commodities, the LOQ value was used for residues <LOQ. The OECD 

procedure yielded an estimate of 0.04 ppm. This was lowered to 0.03 ppm in order to harmonize 

with Codex.

Tea leaf residue values were all (n = 4) substantially above the respective LOQ (0.4 ppm or 1.6 

ppm) and ranged from 0.72 to 4.85 ppm. Values were corrected upward by 4% to account for 

the failure to determine the Z-isomer. The Z-isomer is typically 2 – 7% of the azoxystrobin 

concentration in field trials for other commodities. Additionally, the results were corrected by a 

factor of 2X to account for the field trials being conducted at 50% of the label application rate.

The existing tolerances for group subgroup 1A and crop group 2 are translated to ti palm roots 

and leaves, respectively.

See Appendix B for details.

The coffee processing study was based on a field trial conducted at 5X the label application rate. 

Residues with the coffee beans were <LOQ (<0.02 ppm). Therefore, no processing study is 
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 20 of 25

required (OCSPP 860.1520), and the RAC tolerance will suffice for instant coffee and roasted 

coffee. It is noted that the field trial HAFT for azoxystrobin on green coffee beans (0.016 ppm) 

multiplied by the instant coffee processing study factor (1.7X) yields a processed commodity 

estimate of 0.03 ppm, equivalent to the recommended green coffee bean tolerance (0.03 ppm). 

The factor for roasted beans was lower (1.1X) than for instant coffee.

The HAFT for tea, after correction for application rate, is 9.7 ppm. Using the instant coffee 

processing factor (1.7X), a processed commodity tolerance estimate of 16 ppm is obtained. This 

is less than the recommended dry tea leaf tolerance of 20.0 ppm. The tea leaf tolerance will 

cover the processed commodity instant tea. 
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 21 of 25

Appendix A. International Residue Limits Table

International Residue Limits 

Azoxystrobin (PC Code 128810; 08/21/14)

Summary of US and International Tolerances and Maximum Residue Limits 

Residue Definition: 

US Canada Mexico2 Codex3

40 CFR 180.507:

Plant: sum of azoxystrobin, 

[methyl( E )-2-(2-(6-(2-

cyanophenoxy) pyrimidin-4-

yloxy)phenyl)-3-

methoxyacrylate], and the Zisomer of azoxystrobin [methyl( Z 

)-2-(2-(6-(2-

cyanophenoxy)pyrimidin-4-

yloxy)phenyl)-3 methoxyacrylate] 

(αE)-methyl 2-[[6-(2-

cyanophenoxy)-4-

pyrimidinyl]oxy]-α -

methoxymethylene)benzene

acetate,

including the isomer (Z)-

methyl 2-[[6-(2-

cyanophenoxy)-4-

pyrimidinyl]oxy] -α-

(methoxymethylene)benzen

eacetate

Azoxystrobin.

The residue is fat 

soluble. 

Commodity1 Tolerance (ppm) /Maximum Residue Limit (mg/kg)

US Canada Mexico2 Codex3

Coffee, green bean 0.03 0.06 (pending) 0.03

Pear 0.07 0.07 (pending) None

Tea 20 20 (pending) None

Completed: M. Negussie; 08/21/2014

1

Includes only commodities of interest for this action. Tolerance values should be the HED recommendations and 

not those proposed by the applicant. *The established tolerance should remain at 420 ppm. 

2 Mexico adopts US tolerances and/or Codex MRLs for its export purposes.

3 * = absent at the limit of quantitation; Po = postharvest treatment, such as treatment of stored grains. PoP = 

processed postharvest treated commodity, such as processing of treated stored wheat. (fat) = to be measured on the 

fat portion of the sample. MRLs indicated as proposed have not been finalized by the CCPR and the CAC.
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 22 of 25

Appendix B. OECD MRL Calculation Procedure Inputs/Outputs

Asian Pear (South Korea)

The OECD calculation provides an estimate of 0.07 ppm. Five of seven residue values were 

below the LOQ.

Residues (mg/kg) n

< 0.02 5

0.03 2

0.05 1

Azoxystrobin

Asian Pear

S Korea

5 X 0.4, 7 d PHI

Total number of data (n) 8

Percentage of censored data 63%

Number of non-censored data 3

Lowest residue 0.020

Highest residue 0.050

Median residue 0.020

Mean 0.026

Standard deviation (SD) 0.011

Correction factor for censoring (CF) 0.583

Proposed MRL estimate

- Highest residue 0.050

- Mean + 4 SD 0.069

- CF x 3 Mean 0.046

Unrounded MRL 0.069

Rounded MRL 0.07

High uncertainty of MRL estimate.

[High level of censoring]
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 23 of 25

Coffee Bean (Green)

The OECD procedure provides an estimate of 0.04 ppm. Three of four residue values were 

below the LOQ. Codex has an MRL of 0.03 ppm It is noted that the highest field trial value in 

the current submission was 0.023, or slightly above the 0.02 ppm LOQ. For purposes of 

harmonization, the estimate will be adjusted downward to 0.03 ppm.

Residues (mg/kg) n

< 0.02 3

0.023 1

Azoxystrobin

Coffee Bean

Import

3 X 0.13, 14 d PHI

Total number of data (n) 4

Percentage of censored data 75%

Number of non-censored data 1

Lowest residue 0.020

Highest residue 0.023

Median residue 0.020

Mean 0.021

Standard deviation (SD) 0.002

Correction factor for censoring (CF) 0.500

Proposed MRL estimate

- Highest residue 0.023

- Mean + 4 SD 0.027

- CF x 3 Mean 0.031

Unrounded MRL 0.031

Rounded MRL 0.04

High uncertainty of MRL estimate.

[Small dataset and high level of censoring]
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 24 of 25

Tea, Dried Leaves

Field trial samples were analyzed for azoxystrobin only. All trials (n = 4) had residues much in 

excess of the LOQs. The Z-isomer was not determined. It may be estimated from field trials 

with other commodities.

Commodity DP Barcode Azoxystrobin Mean

(ppm)

Z-Isomer

Mean

(ppm)

Ratio Z / 

Azoxystrobin

Radish top D260134 28.6 0.61 0.021

Spinach D260134 18.9 0.42 0.022

Leaf Lettuce D260134 7.5 0.28 0.037

Mandarin Peel D260134 6.98 0.45 0.064

Field Corn Stover D260134 5.23 0.27 0.052

Dill Seed D312949 15.6 0.83 0.053

Fresh Chives D312949 6.54 0.19 0.029

Dried Chives D312040 38.85 0.83 0.021

AVERAGE 0.037

A factor of 0.04 was used to account for Z-isomer in the dried tea field trial results, that it, 

(measured E-isomer + measured E-isomer X 0.04 = total residue).

Residues (mg/kg) n

0.72 1

2.41 1

3.4 1

4.85 1

However, the total application rate was 0.59 lb ai/acre, whereas the label rate is 1.18 lb ai/acre

(50% of proposed). Each of the three applications was conducted at 50% of the proposed rate 

(0.2 lb ai/acre vs 0.4 lb ai/acre label, and therefore proportionality may be used to adjust for the 

lower rate (50% of proposed). Each trial result is adjusted by a factor of 2X.

Residues (mg/kg) n

1.44 1

4.82 1

6.8 1

9.7 1

Azoxystrobin

Tea, dried

Japan

3 X 0.4, 14 d PHI

Total number of data (n) 4
Azoxystrobin Summary of Analytical Chemistry and Residue Data Barcode D423334; D423718

Page 25 of 25

Percentage of censored data 0%

Number of non-censored data 4

Lowest residue 1.440

Highest residue 9.700

Median residue 5.810

Mean 5.690

Standard deviation (SD) 3.470

Correction factor for censoring (CF) 1.000

Proposed MRL estimate

- Highest residue 9.700

- Mean + 4 SD 19.572

- CF x 3 Mean 17.070

Unrounded MRL 19.572

Rounded MRL 20

High uncertainty of MRL estimate.

[Small dataset]
Azoxystrobin [PC Code 12881 OJ/Syngenta Crop Protection, LLC 

B.7.6 Residues Resulting from Supervised Trials 

(Annex llA 6.3; Annex IHA 8.3) 

B.7.6.1 Residues in Target Crops 

B.7.6,1.1 Pear (Asian) 

Document ID: MRID No. 49227501 

Report: Ellis, C. (2013) Azoxystrobin -Residue Study on Pears in South Korea in 

2012: Final Report. Report/Study Number: S 12-03087. Task Number: 

TK0047640. Unpublished study prepared by Syngenta Crop Protection, 

LLC. 134 p. 

Guidelines: EPA OCSPP Harmonized Test Guideline 860.1500 Crop Field Trials 

(August 1996) 

PMRA Regulatory Directive DIR98-02- Residue Chemistry Guidelines, 

Section 9 - Crop Field Trials 

PMRA Regulatory Directive DIR2010-05 - Revisions to the Residue 

Chemistry Crop Field Trial Requirements 

OECD Guideline 509 Crop Field Trial (September 2009) 

GLP Compliance: No deviations from regulatory requirements were reported which would 

have an impact on the validity of the study. 

Acceptability: The study is considered scientifically acceptable. The acceptability of this 

study for regulatory purposes is addressed in th~ forthcoming U.S. EPA 

Residue Chemistry Summary Document, D.p'# 418374. 

Evaluator: Steve Funk, Senior Chemist, RAB III I · ,J, l , .\ . I l ( ~ J . I \ \ / . . .II 1,,.,, .. / 

Note: This Data Evaluation Record (DER) was originally prepared under contract bJ··versar,\ lnc. (6850 Versar Center, 

Springfield, VA 22151 ; submitted 9130114 ). The DER has been reviewed by HED and revised to reflect current Office of 

Pesticide Programs (OPP) policies. 

EXECUTIVE SUMMARY 

Syngenta Crop Protection, LLC has submitted field trial data for azoxystrobin on Asian pears. 

Eight pear field trials were conducted in South Korea during the 2012 growing season. All pears 

were contained in paper/wax paper bags according to local practices and regulations for this crop 

in South Korea. The bags were placed on the pears well in advance of the first application and 

remained in place until harvest. 

Each trial consisted of one untreated plot and one treated plot. At all trial locations, the treated 

plot received five foliar broadcast applications of a 10% wettable powder (WP) formulation of 

azoxystrobin (A12913A) at 0.359-0.475 lb ai/A/application (402-532 g ai/ha/application) for 

total rates of 1.978-2.081 lb ai/A (2218-2333 g ai/ha). All applications were made at retreatment 

intervals (RTls) of9-11 days using ground equipment in spray volumes of 430-568 gal/A (4024-

5315 L/ha); no adjuvants were used. At all trials, pears were harvested at a 7-day preharvest 

interval (PHI). Additional samples were collected from four trials at 0- and 3-day PHis to assess 

residue decline. 

Pa e 1 of8 

EPA MRID #: 49227501 
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227501

Page 2 of 8

Samples were analyzed for residues of azoxystrobin and its Z-isomer (R23010) using a high 

performance liquid chromatography method with tandem mass spectrometry detection 

(LC/MS/MS), Method RAM 305/03. Acceptable concurrent recoveries were reported for pear 

samples at fortification levels of 0.01 and 0.10 ppm, thus validating the method. The limit of 

quantitation (LOQ; determined as the lowest level of method validation, LLMV) was 0.01 ppm

for each analyte; the LOQ for combined residues was 0.02 ppm.

All samples were maintained frozen at the testing facility, during shipping to the laboratory, and 

were stored frozen until analysis. The field residue samples were stored frozen a maximum of 

66 days (2.2 months) from harvest to analysis. Extraction and analysis dates were not provided; 

however, the petitioner reported the beginning and ending dates for reside analysis. In addition 

the petitioner reported that sample extracts were stored for a maximum of 7 days prior to 

analysis. The available freezer storage stability data indicate that residues of azoxystrobin and 

R230310 are stable when stored frozen (<-18 °C) for up to 2 years in various crops including 

apples (DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98). Adequate storage 

stability data are therefore available to support the storage conditions and intervals for samples in 

the current trials.

Following five foliar broadcast applications of the 10% WP formulation at total rates of 1.978-

2.081 lb ai/A (2218-2333 g ai/ha), individual sample (and per-trial average) combined residues 

of azoxystrobin and its Z-isomer (R230310) were <0.02-<0.05 ppm (<0.02-<0.05 ppm) in/on 

bagged pears harvested at a 7-day PHI. Residues of the Z-isomer were below the LOQ (<0.01 

ppm) in/on all samples. 

In the residue decline trials, residues in pears remained approximately the same through the 7 

days of residue decline. 

I. MATERIALS AND METHODS

A. MATERIALS

Table B.7.6.1.1-1. Nomenclature for Azoxystrobin and Metabolites of Interest.

Common name Azoxystrobin

Identity

Methyl (αE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)-

benzeneacetate

CAS no. 131860-33-8

Company experimental name ICIA5504 (Zeneca), R215504 (Syngenta)

Other synonyms (if applicable) N/A

Metabolite Azoxystrobin, Z-isomer

Identity Methyl (αZ)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)-

benzeneacetate

N N

O O

CN OCH3

O

H3CO
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227501

Page 3 of 8

Table B.7.6.1.1-1. Nomenclature for Azoxystrobin and Metabolites of Interest.

CAS no. Not available

Company experimental name R230310

Other synonyms (if applicable) N/A

B. Study Design

1. Test Procedure

Eight residue trials on pears were conducted in South Korea with a 10% WP formulation 

(A12913A) during the 2012 growing season. All trials, except for those listed in the table below, 

were separated by >20 miles and are therefore considered independent (568_Criteria for 

Independence of Trials 04/23/2013 (EPA and PMRA)). The trials separated by <20 miles have 

been assessed for independence as detailed in the table below. 

Independent Trial Determination1

Trial Nos. Differences Decision

-03, -07, & -08 Distance: trials separated by ≤15 miles

Same variety

No other differences found

Independent. The locations are slightly 

different, and the growing area in South 

Korea is limited.

1

 All assessments are based on the replicate trial guidance presented in draft memo 568_Criteria for Independence of Trials 

04/23/2013 (EPA and PMRA).

Table B.7.6.1.1-2. Trial Numbers and Geographical Locations.

Crop No. 

Trials

NAFTA Growing Zone

Total

1 2 3 4 5 6 7 8 9 10 11 12

Pear Sub.

Not applicable

Req.1

Locations and detailed use patterns for the trials are provided in Table B.7.6.1.1-3. 

Table B.7.6.1.1-3. Study Use Pattern.

Location: 

Town/Village, 

Province, 

Country; Year

(Trial ID)

End-use 

Product1

Method of Application/ 

Timing of Application

Volume

(gal/A)

[L/ha]

Rate per 

Application

(lb ai/A)

[g ai/ha]

Retreatment 

Interval 

(days)

Total Rate

(lb ai/A)

[g ai/ha]

Surfactant/ 

Adjuvant

Namyangju-si, 

Gyeonggi-do, 

South Korea; 

2012 (S12-03087-

01)

10% WP 1. Foliar broadcast to 

bagged fruit; BBCH 75 

477

[4465]

0.399

[447]

-- 1.995

[2237]

None

2. Foliar broadcast to 

bagged fruit; BBCH 76

483

[4519]

0.403

[452]

10

3. Foliar broadcast to 

bagged fruit; BBCH 77

506

[4738]

0.423

[474]

9

N N

O O

CN

O OCH3

H3CO
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227501

Page 4 of 8

Table B.7.6.1.1-3. Study Use Pattern.

Location: 

Town/Village, 

Province, 

Country; Year

(Trial ID)

End-use 

Product1

Method of Application/ 

Timing of Application

Volume

(gal/A)

[L/ha]

Rate per 

Application

(lb ai/A)

[g ai/ha]

Retreatment 

Interval 

(days)

Total Rate

(lb ai/A)

[g ai/ha]

Surfactant/ 

Adjuvant

4. Foliar broadcast to 

bagged fruit; BBCH 77-79

443

[4140]

0.369

[414]

11

5. Foliar broadcast to 

bagged fruit; BBCH 79

481

[4499]

0.401

[450]

9

Whaseong-si, 

Gyeonggi-do, 

South Korea; 

2012 (S12-03087-

02)

10% WP 1. Foliar broadcast to 

bagged fruit; BBCH 75

442

[4137]

0.369

[414]

-- 2.081

[2333]

None

2. Foliar broadcast to 

bagged fruit; BBCH 76

527

[4932]

0.440

[493]

10

3. Foliar broadcast to 

bagged fruit; BBCH 77

547

[5119]

0.457

[512]

10

4. Foliar broadcast to 

bagged fruit; BBCH 78

475

[4440]

0.396

[444]

10

5. Foliar broadcast to 

bagged fruit; BBCH 79

502

[4696]

0.419

[470]

9

Asan-si, 

Chungcheong 

Nam-do, South 

Korea; 2012 

(S12-03087-03)

10% WP 1. Foliar broadcast to 

bagged fruit; BBCH 75

478

[4474]

0.399

[447]

-- 1.978

[2218]

None

2. Foliar broadcast to 

bagged fruit; BBCH 76

489

[4572]

0.408

[457]

10

3. Foliar broadcast to 

bagged fruit; BBCH 77

481

[4504]

0.401

[450]

10

4. Foliar broadcast to 

bagged fruit; BBCH 78

441

[4124]

0.368

[412]

10

5. Foliar broadcast to 

bagged fruit; BBCH 79

483

[4517]

0.403

[452]

9

Palbong-myeon,

Seosan-si, Chung 

Nam-do, South 

Korea; 2012

(S12-03087-04)

10% WP 1. Foliar broadcast to 

bagged fruit; BBCH 75

430

[4024]

0.359

[402]

-- 2.031

[2277]

None

2. Foliar broadcast to 

bagged fruit; BBCH 76

517

[4832]

0.431

[483]

11

3. Foliar broadcast to 

bagged fruit; BBCH 77

497

[4647]

0.414

[464]

10

4. Foliar broadcast to 

bagged fruit; BBCH 78

512

[4791]

0.427

[479]

10

5. Foliar broadcast to 

bagged fruit; BBCH 79

480

[4489]

0.401

[449]

9

Daewol-myeon, 

Icheon-si, 

Gyeonggi-do, 

South Korea; 

2012

(S12-03087-05)

10% WP 1. Foliar broadcast to 

bagged fruit; BBCH 75

460

[4300]

0.384

[430]

-- 2.047

[2295]

None

2. Foliar broadcast to 

bagged fruit; BBCH 76

520

[4865]

0.434

[486]

10

3. Foliar broadcast to 

bagged fruit; BBCH 77

516

[4824]

0.430

[482]

10

4. Foliar broadcast to 

bagged fruit; BBCH 78

496

[4640]

0.414

[464]

11

5. Foliar broadcast to 

bagged fruit; BBCH 79

463

[4329]

0.386

[433]

9

Yanseong-myeon, 

Anseon-si, 

Gyeonggi-do, 

South Korea; 

2012

(S12-03087-06)

10% WP 1. Foliar broadcast to 

bagged fruit; BBCH 75

474

[4433]

0.395

[443]

-- 2.066

[2316]

None

2. Foliar broadcast to 

bagged fruit; BBCH 76

484

[4527]

0.404

[453]

10

3. Foliar broadcast to 

bagged fruit; BBCH 77

501

[4689]

0.418

[469]

10
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227501

Page 5 of 8

Table B.7.6.1.1-3. Study Use Pattern.

Location: 

Town/Village, 

Province, 

Country; Year

(Trial ID)

End-use 

Product1

Method of Application/ 

Timing of Application

Volume

(gal/A)

[L/ha]

Rate per 

Application

(lb ai/A)

[g ai/ha]

Retreatment 

Interval 

(days)

Total Rate

(lb ai/A)

[g ai/ha]

Surfactant/ 

Adjuvant

4. Foliar broadcast to 

bagged fruit; BBCH 78

521

[4878]

0.435

[488]

10

5. Foliar broadcast to 

bagged fruit; BBCH 79

495

[4626]

0.413

[463]

9

Sungnam-myeon, 

Dongnam-gu, 

Cheon-an-si, 

Chungcheong 

Nam-do, South 

Korea; 2012 

(S12-03087-07)

10% WP 1. Foliar broadcast to 

bagged fruit; BBCH 75

461

[4316]

0.385

[432]

-- 2.003

[2246]

None

2. Foliar broadcast to 

bagged fruit; BBCH 76

513

[4795]

0.427

[479]

10

3. Foliar broadcast to 

bagged fruit; BBCH 77

506

[4731]

0.422

[473]

10

4. Foliar broadcast to 

bagged fruit; BBCH 78

441

[4125]

0.368

[413]

10

5. Foliar broadcast to 

bagged fruit; BBCH 79

480

[4493]

0.401

[449]

9

Eumbong-myeon, 

Yesan-gun, 

Chung Nam-do, 

South Korea; 

2012

(S12-03087-08)

10% WP 1. Foliar broadcast to 

bagged fruit; BBCH 75

455

[4253]

0.379

[425]

-- 2.054

[2303]

None

2. Foliar broadcast to 

bagged fruit; BBCH 76

568

[5315]

0.475

[532]

11

3. Foliar broadcast to 

bagged fruit; BBCH 77

480

[4491]

0.401

[449]

10

4. Foliar broadcast to 

bagged fruit; BBCH 78

481

[4500]

0.401

[450]

10

5. Foliar broadcast to 

bagged fruit; BBCH 79

478

[4473]

0.399

[447]

9

1

 End-use Product is a 10% wettable powder (WP) formulation (A12913A).

Pears were grown and maintained according to typical agricultural practices. This included 

having the pears enclosed in bags throughout the test period. Irrigation was not used. No 

unusual weather conditions were reported during the study, except at one trial (-04) where the 

second application was delayed 1 day due to a typhoon. This had no impact on the study.

Sample Handling and Preparation

At all test sites, triplicate control and treated pear samples were harvested at normal commercial 

harvest (7-day PHI). Additional samples were also collected at PHIs of 0 and 3 days from four 

trials to assess residue decline. Fruits were removed from bags and placed in frozen storage at 

the field sites within 9 hours of collection. All samples were shipped within 16-27 days on dry 

ice to Eurofins Agrosciences Services Ltd. (Derbyshire, UK) for preparation and analysis. In 

preparation for analysis, the stems were removed, and the samples were homogenized in the 

presence of dry ice. Following preparation, samples were stored frozen (~≤-18 °C) at the 

analytical laboratory prior to analysis.

2. Description of Analytical Procedures

Samples were analyzed for residues of azoxystrobin and its Z-isomer (R230310) using an 

LC/MS/MS method, Method RAM 305/03. A brief description of the method was included in 
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227501

Page 6 of 8

the submission.

Briefly, samples were extracted twice with acetonitrile (ACN):water (90:10, v:v). After 

centrifugation, the combined extracts were cleaned up on a C18 solid phase extraction column

for analysis by LC/MS/MS.

The LOQ (determined as the LLMV) was 0.01 ppm for each analyte; the LOQ for combined 

residues was 0.02 ppm. The limit of detection (LOD) was not reported.

II. RESULTS AND DISCUSSION

Method performance was evaluated by use of concurrent recovery samples. Samples of 

untreated pear were fortified with azoxystrobin and R230310 each at 0.01 and 0.10 ppm. 

Recoveries were within the acceptable range of 70%-120%; therefore, the method was 

considered valid for the analysis of residues of azoxystrobin and R230310 in pear (Table 

B.7.6.1.1-4). The fortification levels bracketed the measured residues. It could not be 

determined whether concurrent recoveries were corrected for apparent residues in controls.

The detector response was linear (coefficient of determination, r2 ≥0.9998) within the range of 

0.00005-0.01 μg/mL. Representative chromatograms of control samples, fortified samples and 

treated samples were provided. The control chromatograms generally had no peaks of interest 

above the chromatographic background. The fortified sample chromatograms contained only the 

analyte of interest, and peaks were symmetrical and well defined. Apparent residues in controls 

were below the LOQ (<0.01 ppm) for both analytes. The reported residue values were not 

corrected for apparent residues in controls.

Table B.7.6.1.1-4. Summary of Procedural/Concurrent Recoveries of Azoxystrobin and 

its Z-isomer (R230310) from Pear.

Matrix Analyte Fortification 

Level (ppm)

Sample 

size (n)

Recoveries1

(%)

Mean ± RSD

(%)

Pear, Asian Azoxystrobin 0.01-0.10 4 90-112 99 ± 10

R230310 0.01-0.10 4 84-91 89 ± 3.5

1

It could not be determined whether concurrent recoveries were corrected for apparent residues in controls.

The field residue samples were stored frozen a maximum of 66 days (2.2 months) from harvest 

to analysis (Table B.7.6.1.1-5). Extraction and analysis dates were not provided; however, the 

petitioner reported the reside analysis period (11/15/12-11/28/12). In addition the petitioner 

reported that sample extract solutions were stored for a maximum of 7 days prior to analysis. 

The available freezer storage stability data indicate that residues of azoxystrobin and R230310 

are stable when stored frozen (<-18 °C) for up to 2 years in various crops including apples (DP#

248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98). 

Table B.7.6.1.1-5. Summary of Storage Conditions.

Matrix Storage Temperature 

(°C)

Actual Storage Duration1Interval of Demonstrated Storage Stability
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227501

Page 7 of 8

Pear ≤-18 42-66 days

(1.4-2.2 months)

Residues of azoxystrobin and R230310 are stable 

for up to 2 years in various crops including apples 

stored frozen (<-18 °C).

1

Interval from harvest to analysis. The petitioner indicated samples were analyzed within 7 days of extraction.

2 DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98

The results from the submitted field trials are presented in Tables B.7.6.1.1-6 and B.7.6.1.1-7. 

Following five foliar broadcast applications of the 10% WP formulation at total rates of 1.978-

2.081 lb ai/A (2218-2333 g ai/ha), individual sample (and per-trial average) combined residues 

of azoxystrobin and its Z-isomer (R230310) were <0.02-<0.05 ppm (<0.02-<0.05 ppm) in/on 

bagged pears harvested at a 7-day PHI. Residues of the Z-isomer were below the LOQ (<0.01 

ppm) in/on all samples. 

In the residue decline trials, residues in pears remained approximately the same through the 7 

days of residue decline. 

Table B.7.6.1.1-6. Residue Data from Pear Field Trials with Azoxystrobin.

1

Location: Town/Village, 

Province, Country; Year (Trial 

ID)

Variety Matrix Rate

(lb ai/A)

[g ai/ha]

PHI

(days)

Residues2(ppm) [Average]

Azoxystrobin R230310 Combined3

Namyangju-si, Gyeonggi-do, 

South Korea; 2012 (S12-03087-

01)

Shin-go Fruit 1.995

[2237]

0 <0.01, <0.01

[<0.01]

<0.01, <0.01

[<0.01]

<0.02, <0.02

[<0.02]

3 0.02, <0.01

[<0.02]

<0.01, <0.01

[<0.01]

<0.03, <0.02

[<0.03]

7 0.02, 0.01

[0.02]

<0.01, <0.01

[<0.01]

<0.03, <0.02

[<0.03]

Whaseong-si, Gyeonggi-do, 

South Korea; 2012 (S12-03087-

02)

Shin-go Fruit 2.081

[2333]

0 0.01, 0.02

[0.02]

<0.01, <0.01

[<0.01]

<0.02, <0.03

[<0.03]

3 <0.01, 0.02

[<0.02]

<0.01, <0.01

[<0.01]

<0.02, <0.03

[<0.03]

7 <0.01, 0.02

[<0.02]

<0.01, <0.01

[<0.01]

<0.02, <0.03

[<0.03]

Asan-si, Chungcheong Nam-do, 

South Korea; 2012 (S12-03087-

03)

Shin-go Fruit 1.978

[2218]

7 0.01, <0.01, 

[<0.01]

<0.01, <0.01, 

[<0.01]

<0.02, <0.02, 

[<0.02]

Palbong-myeon, Seosan-si, 

Chung Nam-do, South Korea; 

2012 (S12-03087-04)

Shin-go Fruit 2.031

[2277]

7 <0.01, <0.01

[<0.01]

<0.01, <0.01

[<0.01]

<0.02, <0.02

[<0.02]

Daewol-myeon, Icheon-si, 

Gyeonggi-do, South Korea; 

2012

(S12-03087-05)

Shin-go Fruit 2.047

[2295]

0 <0.01, <0.01

[<0.01]

<0.01, <0.01

[<0.01]

<0.02, <0.02

[<0.02]

3 <0.01, <0.01

[<0.01]

<0.01, <0.01

[<0.01]

<0.02, <0.02

[<0.02]

7 <0.01, 0.01

[<0.01]

<0.01, <0.01

[<0.01]

<0.02, <0.02

[<0.02]

Yanseong-myeon, Anseon-si, 

Gyeonggi-do, South Korea; 

2012

(S12-03087-06)

Shin-go Fruit 2.066

[2316]

0 0.03, 0.05

[0.04]

<0.01, <0.01

[<0.01]

<0.04, <0.06

[<0.05]

3 0.03, 0.03

[0.03]

<0.01, <0.01

[<0.01]

<0.04, <0.04

[<0.04]

7 0.04, 0.04

[0.04]

<0.01, <0.01

[<0.01]

<0.05, <0.05

[<0.05]
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227501

Page 8 of 8

Table B.7.6.1.1-6. Residue Data from Pear Field Trials with Azoxystrobin.

1

Location: Town/Village, 

Province, Country; Year (Trial 

ID)

Variety Matrix Rate

(lb ai/A)

[g ai/ha]

PHI

(days)

Residues2(ppm) [Average]

Azoxystrobin R230310 Combined3

Sungnam-myeon, Dongnam-gu, 

Cheon-an-si, Chungcheong 

Nam-do, South Korea; 2012 

(S12-03087-07)

Shin-go Fruit 2.003

[2246]

7 <0.01, 0.01

[<0.01]

<0.01, <0.01

[<0.01]

<0.02, <0.02

[<0.02]

Eumbong-myeon, Yesan-gun, 

Chung Nam-do, South Korea; 

2012

(S12-03087-08)

Shin-go Fruit 2.054

[2303]

7 <0.01, 0.01

[<0.01]

<0.01, <0.01

[<0.01]

<0.02, <0.02

[<0.02]

1 End-use Product is a 10% wettable powder (WP) formulation (A12913A).

2 The LOQ was 0.01 ppm for each analyte. The LOD was not reported. Combined residues and per-trial averages were

calculated by the study reviewer using the LOQ for all residues reported as <LOQ.

3 Combined residues of azoxystrobin and its Z-isomer (R230310)

Table B.7.6.1.1-7. Summary of Residues from Pear Field Trials with Azoxystrobin.

Crop Matrix Total Application Rate

(lb ai/A) [g ai/ha]

PHI 

(days)

n

1 Residues Azoxystrobin2

(ppm)

Min.3 Max.3 LAFT4 HAFT4 Median4 Mean4 SD4

Pear (bagged) 1.978-2.081

[2218-2333]

7 8 <0.02 <0.05 <0.02 <0.05 0.02 0.03 0.01

1 n = number of field trials.

2 Combined residues of azoxystrobin and its Z-isomer (R230310).

3 Values based on total number of samples.

4 Values based on per-trial averages. LAFT = lowest average field trial, HAFT = highest average field trial, SD = standard 

deviation. For computation of the LAFT, HAFT, median, mean, and standard deviation, values <LOQ are assumed to be at the 

LOQ (0.01 ppm).

III. CONCLUSIONS

The pear field trials are considered scientifically acceptable. Following five foliar broadcast 

applications of the 10% WP formulation at total rates of 1.978-2.081 lb ai/A (2218-2333 g ai/ha), 

individual sample (and per-trial average) combined residues of azoxystrobin and its Z-isomer 

(R230310) were <0.02-<0.05 ppm (<0.02-<0.05 ppm) in/on bagged pears harvested at a 7-day 

PHI. Residues of the Z-isomer were below the LOQ (<0.01 ppm) in/on all samples. In the 

residue decline trials, residues in pears remained approximately the same through the 7 days of 

residue decline. 

An acceptable method was used for residue quantitation, and adequate storage stability data are 

to support sample storage durations and conditions for all analytes. 

REFERENCES

DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98
Azoxystrobin [PC Code 1288 l O]/Syngenta Crop Protection, LLC 

B.7.6 Residues Resulting from Supervised Trials 

(Annex IIA 6.3; Annex IIIA 8.3) 

B.7.6.1 Residues in Target Crops 

B.7.6.1.3 Tea 

Document ID: MRID No. 49227502 

Report: 

Guidelines: 

Smith, N. (2013) Azoxystrobin SC (A13364A) - Compilation of Residue 

Data in or on Tea. Summary. Report/Task Number: TK0185024. 

Unpublished study prepared by Syngenta Crop Protection, LLC. 110 p. 

EPA OCSPP Harmonized Test Guideline 860.1500 Crop Field Trials 

(August 1996) 

PMRA Regulatory Directive DIR98-02 - Residue Chemistry Guidelines, 

Section 9 - Crop Field Trials 

PMRA Regulatory Directive DIR2010-05 - Revisions to the Residue 

Chemistry Crop Field Trial Requirements 

OECD Guideline 509 Crop Field Trial (September 2009) 

GLP Compliance: No deviations from regulatory requirements were reported which would 

Acceptability: 

Evaluator: 

have an impact on the validity of the study. 

The study is considered scientifically acceptable. The acceptability of this 

study for regulatory purposes is addressed in the fort!woming U.S. EPA 

Residue Chemistry Summary Document, DP#~83 · . 

Steve Funk, Senior Chemist, RAB III 1 ~ ,L.LM.~ 

·v 

Note: This Data Evaluation Record (DER) was originally prepared under contract by Versar, Inc. (6850 Versar Center, 

Springfield, VA 22151; submitted 9/30/14). The DER has been reviewed by HED and revised to reflect current Office of 

Pesticide Programs (OPP) policies. 

EXECUTIVE SUMMARY 

Syngenta Crop Protection, LLC has submitted residue data for azoxystrobin on tea. Four tea 

field trials for were conducted in Japan during the 1998 growing season. 

Each trial consisted of one untreated plot and one treated plot divided into three subplots (2, 3, 

and 4) to establish separate preharvest intervals (PHis). Each treated plot received three foliar 

spray applications of a 20% suspension concentrate (SC) formulation of azoxystrobin 

(Amistar® 20 SC) at 0.196 lb ail A/application (220 g ai/ha/application), for a total rate of 0.589 

lb ai/A (660 g ai/ha). All applications were made at retreatment intervals (RTis) of 7 days using 

ground equipment in spray volumes of 214 gal/A (2000 L/ha); no adjuvants were used. Single 

samples of green tea leaves were harvested at PHis of 7, 14, and 21 days from subplots 2, 3, and 

4, respectively, and were processed into dried crude tea (dried leaves). 

EPA MRID #: 49227502 

Pagel of 10 
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227502

Page 2 of 10

Separate subsamples from each trial were analyzed for residues of azoxystrobin at two analytical 

laboratories, Japan Analytical Chemistry Consultants Co., Ltd. (JACC) and Japan Food Research 

Laboratories (JFRL). The laboratories used different high performance liquid chromatography 

methods with UV detection (HPLC/UV). Acceptable concurrent recoveries were reported for tea 

samples fortified with azoxystrobin and its Z-isomer (R230310) at 0.4 ppm each (JACC) and 

with azoxystrobin at 1.6 and 10 ppm (JFRL), thus validating the methods. The fortification 

levels used at JFRL bracketed the measured residues; however, the fortification level used at 

JACC was more than an order of magnitude lower than the highest measured residues. The 

reported limits of quantitation (LOQs; calculated from the minimum detectable residues) were

0.02 ppm for the JACC method and 0.04 ppm for the JFRL method.

The petitioner indicated that in Japan the residue of concern is parent azoxystrobin only, and that 

therefore, residues of the Z-isomer (R230310) were not determined in field trial samples by

either laboratory. Concurrent recovery and storage stability data generated by JACC included 

analysis for R230310. 

All samples were maintained refrigerated at the testing facilities and were stored frozen until 

analysis at the analytical laboratories. The field residue samples were stored frozen from harvest 

to analysis for a maximum of 89 days (2.9 months) at JACC and 113 days (3.7 months) at JFRL. 

Extraction dates were not provided. To support sample storage durations, each laboratory 

conducted a concurrent storage stability study. The data demonstrate that residues of 

azoxystrobin and R230310 were stable in/on dried leaves stored frozen for up to 67-83 days (2.2-

2.7 months) at JACC and that residues of azoxystrobin were stable in/on dried leaves stored 

frozen for up to 108-122 days (3.6-4.0 months) at JFRL; no 0-day data were provided. These 

data are acceptable to support the storage conditions and durations of samples from the submitted 

field trials; however, storage stability studies should always include a 0-day sampling interval to 

establish the residue levels present at the time samples are placed into storage [see OCSPP 

860.1380(d)(6)(i)]. 

Following three foliar spray applications of the 20% SC formulation at a total rate of 0.589 lb 

ai/A (660 g ai/ha), residues of azoxystrobin, determined by averaging results from both 

laboratories, were 1.56-11.5, 0.69-4.66, and 0.23-1.44 ppm, respectively, in/on samples of dried 

tea leaves harvested at PHIs of 7, 14, and 21 days. Residues of azoxystrobin decreased in dried 

leaves with increasing PHIs.

I. MATERIALS AND METHODS

A. MATERIALS

Table B.7.6.1.3-1. Nomenclature for Azoxystrobin and Metabolites of Interest.

Common name Azoxystrobin

Identity

Methyl (αE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)-

benzeneacetate

CAS no. 131860-33-8

Company experimental name ICIA5504 (Zeneca), R215504 (Syngenta)
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227502

Page 3 of 10

Table B.7.6.1.3-1. Nomenclature for Azoxystrobin and Metabolites of Interest.

Other synonyms (if applicable) N/A

Metabolite Azoxystrobin, Z-isomer

Identity Methyl (αZ)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)-

benzeneacetate

CAS no. Not available

Company experimental name R230310

Other synonyms (if applicable) N/A

B. Study Design

1. Test Procedure

Four residue trials on tea were conducted in Japan with a 20% SC formulation (Amistar® 20 SC)

during the 1998 growing season. All trials were separated by >20 miles and are therefore 

considered independent (568_Criteria for Independence of Trials 04/23/2013 (EPA and 

PMRA)).

Table B.7.6.1.3-2. Trial Numbers and Geographical Locations.

Crop No. 

Trials

NAFTA Growing Zone

Total

1 2 3 4 5 6 7 8 9 10 11 12

Tea Sub.

Not applicable

Req.1

Table B.7.6.1.3-3. Study Use Pattern.

Location: City, 

Prefecture, 

Country; Year

End-use 

Product1

Subplot Method of Application/ 

Timing of Application

Volume

(gal/A)

[L/ha]

Rate per 

Application

(lb ai/A)

[g ai/ha]

Retreatment 

Interval 

(days)

Total Rate

(lb ai/A)

[g ai/ha]

Surfactant/ 

Adjuvant

Kanagawa 

Agricultural 

Technology 

Center

Tsukui-gun, 

Kanagawa, 

Japan; 1998

20% SC 2 1. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 14 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 7 days 

before harvest

214

[2000]

0.196

[220]

7

3 1. Foliar spray; 28 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

N N

O O

CN OCH3

O

H3CO

N N

O O

CN

O OCH3

H3CO
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227502

Page 4 of 10

Table B.7.6.1.3-3. Study Use Pattern.

Location: City, 

Prefecture, 

Country; Year

End-use 

Product1

Subplot Method of Application/ 

Timing of Application

Volume

(gal/A)

[L/ha]

Rate per 

Application

(lb ai/A)

[g ai/ha]

Retreatment 

Interval 

(days)

Total Rate

(lb ai/A)

[g ai/ha]

Surfactant/ 

Adjuvant

2. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 14 days 

before harvest

214

[2000]

0.196

[220]

7

4 1. Foliar spray; 35 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 28 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

7

Mie Plant 

Protection 

Association

Ichishi-gun, Mie, 

Japan; 1998

20% SC 2 1. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 14 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 7 days 

before harvest

214

[2000]

0.196

[220]

7

3 1. Foliar spray; 28 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 14 days 

before harvest

214

[2000]

0.196

[220]

7

4 1. Foliar spray; 35 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 28 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

7
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227502

Page 5 of 10

Table B.7.6.1.3-3. Study Use Pattern.

Location: City, 

Prefecture, 

Country; Year

End-use 

Product1

Subplot Method of Application/ 

Timing of Application

Volume

(gal/A)

[L/ha]

Rate per 

Application

(lb ai/A)

[g ai/ha]

Retreatment 

Interval 

(days)

Total Rate

(lb ai/A)

[g ai/ha]

Surfactant/ 

Adjuvant

Nara Agricultural 

Experiment 

Station; Tea 

Branch

Yatawara-cho, 

Nara-shi, Japan; 

1998

20% SC 2 1. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 14 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 7 days 

before harvest

214

[2000]

0.196

[220]

7

3 1. Foliar spray; 28 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 14 days 

before harvest

214

[2000]

0.196

[220]

7

4 1. Foliar spray; 35 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 28 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

7

Kochi 

Agricultural 

Research Center; 

Tea Experiment 

Station

Takaoka-gun, 

Kochi, Japan; 

1998

20% SC 2 1. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 14 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 7 days 

before harvest

214

[2000]

0.196

[220]

7

3 1. Foliar spray; 28 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 14 days 

before harvest

214

[2000]

0.196

[220]

7

4 1. Foliar spray; 35 days 

before harvest

214

[2000]

0.196

[220]

-- 0.589

[660]

None

2. Foliar spray; 28 days 

before harvest

214

[2000]

0.196

[220]

7

3. Foliar spray; 21 days 

before harvest

214

[2000]

0.196

[220]

7

1

 End-use Product is a 20% (by weight) suspension concentrate (SC) formulation (Amistar® 20 SC).

Tea plants were grown and maintained according to typical agricultural practices. Irrigation was

not used. No unusual weather conditions were reported during the study.

Sample Handling and Preparation

Single control and treated samples of green tea leaves (≥2 kg) were collected 7, 14, and 21 days 

after the last application of the test substance from separate subplots at each trial site. After 

collection, samples were processed into dried leaves. Briefly, green tea leaves were steamed 
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227502

Page 6 of 10

followed by kneading and then dried. Samples of dried leaves were stored in the refrigerator for 

0-6 days until shipment to the analytical laboratories, Japan Analytical Chemistry Consultants 

Co., Ltd. (JACC) and Japan Food Research Laboratories (JFRL), where they were stored frozen 

(-20 °C) until they were ground for analysis.

2. Description of Analytical Procedures

Separate subsamples from each trial were analyzed for residues of azoxystrobin (but not the Z 

isomer) at two analytical laboratories, JACC and JFRL using different HPLC/UV methods. 

Complete descriptions of the methods were included in the submission. The reported LOQs

(calculated from the minimum detectable residues) were 0.02 ppm for the JACC method and 

0.04 ppm for the JFRL method.

JACC method: Briefly, samples were extracted with acetonitrile (ACN):water (1:3, v:v), 

filtered, and concentrated under reduced pressure by rotary evaporation. The extract was 

partitioned twice with ethyl acetate containing saturated sodium chloride solution, and the 

combined ethyl acetate layer was filtered through anhydrous sodium sulfate, reduced to dryness,

and redissolved in acetone. The extract was combined with coagulant solution (ammonium 

chloride and phosphoric acid in water), concentrated, and partitioned with ethyl acetate/sodium 

chloride solution and reduced to dryness as above, then dissolved in acetone:hexane (30:70, v:v). 

The resulting extract was further purified by sequential solid-phase extraction (SPE) on two 

silica gel columns followed by an alumina column; residues were eluted with acetone:hexane 

(30:70, 5:95, and 20:80 v:v). The final eluate was concentrated, evaporated to dryness, and 

redissolved in ACN:water (1:1, v:v) for HPLC analysis. 

JFRL method: Briefly, samples were extracted with acetone, filtered, and vacuum concentrated. 

Sodium chloride and water were added and the extract was purified using porous diatomaceous 

earth column chromatography. Residues were eluted with ethyl acetate, and the eluate was 

vacuum concentrated, evaporated to dryness under nitrogen, and redissolved in water:ACN (8:2, 

v:v). The extract was further purified by sequential SPE on a C18 silica column (residues eluted 

with water:ACN (1:1, v:v) and redissolved in ethyl acetate), activated carbon column (residues 

eluted with ethyl acetate and redissolved in acetone:hexane (1:19, v:v)), and Florisil column 

(residues eluted with hexane:acetone (8:2, v:v) and redissolved in ACN:water (1:1, v:v)) for 

analysis by HPLC/UV. 

II. RESULTS AND DISCUSSION

Method performance was evaluated at each laboratory by use of concurrent recovery samples

fortified with azoxystrobin and its Z-isomer (R230310) at 0.4 ppm each (JACC) and with 

azoxystrobin at 1.6 and 10 ppm (JFRL). Recoveries at both laboratories were within the 

acceptable range of 70-120%; therefore, the methods were considered valid for the analysis of 

azoxystrobin and R230310 residues in tea matrices (Table B.7.6.1.3-4). The fortification levels 

used at JFRL bracketed the measured residues; however, the fortification level used at JACC was 

more than an order of magnitude lower than the highest measured residues. Concurrent 

recoveries were not corrected for apparent residues in controls.
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227502

Page 7 of 10

Standard curves were provided indicating that the detector response was linear within the range 

of 0.025-0.5 ppm (JACC) and 0.025-1.0 ppm (JFRL); coefficients of determination were not 

reported. Representative chromatograms of control samples, fortified samples and treated 

samples were provided. The control chromatograms generally had no peaks of interest above the 

chromatographic background. The fortified sample chromatograms contained only the analyte of 

interest, and peaks were symmetrical and well defined. Apparent residues in controls were

below the method LOQ (<0.02 ppm for the JACC method and <0.04 ppm for the JFRL method) 

with the exception of the untreated sample from the Kochi site which bore detectable residues of 

azoxystrobin at 0.06 ppm (detected by both laboratories). The reported residue values were not 

corrected for apparent residues in controls.

Table B.7.6.1.3-4. Summary of Procedural/Concurrent Recoveries of Azoxystrobin and its 

Z-isomer (R230310) from Tea1.

Matrix Analyte Fortification 

Level

(ppm)

Sample 

size (n)

Recoveries1

(%)

Mean ± Std. Dev.

(%)

JACC method

Dried leaves Azoxystrobin 0.4 8 89, 86, 86.2, 84.1, 92.3, 88.3, 86.5, 82 86.8 ± 3.1

R230310 8 84.6, 83.5, 84.3, 77.8, 80.7, 77.8, 78.9, 75.5 80.4 ± 3.4

JFRL method

Dried leaves Azoxystrobin 1.6 8 101, 92, 101, 98, 101, 92, 96, 95 97 ± 3.9

10 4 96, 93, 94, 93 94 ± 1.4

1 Concurrent recoveries were not corrected for apparent residues in controls.

The field residue samples were stored frozen from harvest to analysis for a maximum of 89 days

(2.9 months) at JACC and 113 days (3.7 months) at JFRL (Table B.7.6.1.3-5). Extraction dates 

were not provided. To support sample storage durations, each laboratory conducted a concurrent 

storage stability study; the results are presented in Table B.7.6.1.3-6. The data demonstrate that 

residues of azoxystrobin and R230310 were stable in/on dried leaves stored frozen for up to 67-

83 days (2.2-2.7 months) at JACC and that residues of azoxystrobin were stable in/on dried 

leaves stored frozen for up to 108-122 days (3.6-4.0 months) at JFRL; no 0-day data were 

provided. These data are acceptable to support the storage conditions and durations of samples 

from the submitted field trials; however, storage stability studies should always include a 0-day 

sampling interval to establish the residue levels present at the time samples are placed into 

storage [see OCSPP 860.1380(d)(6)(i)]. 

Table B.7.6.1.3-5. Summary of Storage Conditions.

Matrix Storage 

Temperature (°C)

Actual Storage Duration1Interval of Demonstrated Storage Stability

JACC method

Tea, dried leaves -20 79-89 days (2.6-2.9 months) 67-83 days (2.2-2.7 months)2

JRFL Method

Tea, dried leaves -20 106-113 days (3.5-3.7 months) JFRL: 108-122 days (3.6-4.0 months)2

1

Interval from harvest to analysis. Extraction dates were not reported.

2 Based on concurrent storage stability studies. See Table 7.6.1.3-5b.
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227502

Page 8 of 10

Table B.7.6.1.3-6. Stability of Azoxystrobin Residues in Tea.

Commodity/location Analyte Spike

Level

(ppm)

Storage 

interval

(days)

Fresh Fortification 

Recoveries (%)

[Avg.]

Stored 

Sample 

Recoveries 

(%)

Mean 

Recovery 

(%)

Corrected % 

recovery1

JACC Method

Dried leaves/

Kanagawa Agricultural 

Technology Center/Tea

Azoxystrobin 1.0 67 89.0, 86.0 [87.5] 93.3, 92.2 92.8 106

R230310 67 84.6, 83.5 [84.0] 95.8, 95.6 95.7 114

Dried leaves/

Mie Plant Protection 

Association/Tea

Azoxystrobin 1.0 83 86.2, 84.1 [85.2] 90.3, 88.6 89.7 105

R230310 83 84.3, 77.8 [81.0] 95.2, 93.6 94.4 116

Dried leaves/

Nara Agricultural 

Experiment Station/Tea

Azoxystrobin 1.0 76 92.3, 88.3 [90.3] 80.8, 76.3 78.6 87.0

R230310 76 80.7, 77.8 [79.2] 80.7, 79.8 80.2 101

Dried leaves/

Kochi Agricultural 

Research Center/Tea

Azoxystrobin 1.0 83 86.5, 82.0 [84.2] 81.7, 81.0 81.4 96.7

R230310 83 78.9, 75.5 [77.2] 74.7, 74.0 74.4 96.4

JFRL Method2

Dried leaves/

Kanagawa Agricultural 

Technology Center/Tea

Azoxystrobin 2 108 101, 92, 101, 98, 

101, 92, 95, 96

[97]2

89, 88 88 91

Dried leaves/

Mie Plant Protection 

Association/Tea

Azoxystrobin 2 122 84, 83 84 87

Dried leaves/

Nara Agricultural 

Experiment Station/Tea

Azoxystrobin 2 119 91, 88 90 93

Dried leaves/

Kochi Agricultural 

Research Center/Tea

Azoxystrobin 2 122 94, 92 93 96

1 Corrected by the petitioner based on the recovery of concurrent recovery samples for the analytical procedure.

2 Recoveries from the 1.6-ppm fortification level.

The results from the submitted field trials are presented in Tables B.7.6.1.3-7 and B.7.6.1.3-8. 

Following three foliar spray applications of the 20% SC formulation at a total rate of 0.589 lb 

ai/A (660 g ai/ha), residues of azoxystrobin, determined by averaging results from both 

laboratories, were 1.56-11.5, 0.69-4.66, and 0.23-1.44 ppm, respectively, in/on samples of dried 

tea leaves harvested at PHIs of 7, 14, and 21 days. Residues of azoxystrobin decreased in dried 

leaves with increasing PHIs.

Table B.7.6.1.3-7. Residue Data from Tea Field Trials with Azoxystrobin.

1

Location:

City, Prefecture, Country; Year

Tea Variety Matrix Rate

(lb ai/A)

[g ai/ha]

PHI

(days)

Residues2(ppm) [Average]

JACC

Method

JFRL 

Method

Average results 

both methods3

Kanagawa Agricultural 

Technology Center Tsukui-gun, 

Kanagawa, Japan; 1998

Yabukita Dried 

leaves

0.589

[660]

7 10.2 10.5 10.3

14 4.56 4.75 4.66

21 1.38 1.51 1.44

Mie Plant Protection Association

Ichishi-gun, Mie, Japan; 1998

Yabukita Dried 

leaves

0.589

[660]

7 7.44 7.78 7.61

14 2.02 2.62 2.32

21 0.95 1.17 1.06
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227502

Page 9 of 10

Table B.7.6.1.3-7. Residue Data from Tea Field Trials with Azoxystrobin.

1

Location:

City, Prefecture, Country; Year

Tea Variety Matrix Rate

(lb ai/A)

[g ai/ha]

PHI

(days)

Residues2(ppm) [Average]

JACC

Method

JFRL 

Method

Average results 

both methods3

Nara Agricultural Experiment 

Station; Tea Branch

Yatawara-cho, Nara-shi, Japan; 

1998

Yabukita Dried 

leaves

0.589

[660]

7 1.41 1.71 1.56

14 0.58 0.80 0.69

21 0.20 0.26 0.23

Kochi Agricultural Research 

Center; Tea Experiment Station

Takaoka-gun, Kochi, Japan; 1998

Yabukita Dried 

leaves

0.589

[660]

7 9.93 13.1 11.5

14 3.09 3.46 3.27

21 0.53 0.66 0.59

1 End-use Product is a 20% (by weight) SC formulation (Amistar® 20 SC).

2 Residues reported for azoxystrobin per se; residues of R230310 were not determined. All values are the mean of duplicate 

analyses calculated by the study reviewer from reported values. 

3 Average of analytical results from both JACC Method and JRFL Method calculated by the study reviewer.

Table B.7.6.1.3-8. Summary of Residues from Tea Field Trials with Azoxystrobin.

Crop Matrix Analyte Total 

Application 

Rate

(lb ai/A)

[g ai/ha]

PHI 

(days)

n

1 Residues (ppm)

Min.2 Max.2 LAFT3 HAFT3 Median3 Mean3 SD3

JACC Method

Tea, dried 

leaves

Azoxystrobin 0.589

[660]

7 4 1.41 10.2 1.41 10.2 8.68 7.25 4.09

14 4 0.58 4.56 0.58 4.56 2.56 2.56 1.68

21 4 0.20 1.38 0.20 1.38 0.74 0.76 0.51

JFRL Method

Tea, dried 

leaves

Azoxystrobin 0.589

[660]

7 4 1.71 13.1 1.71 13.1 9.12 8.26 4.88

14 4 0.80 4.75 0.80 4.75 3.04 2.90 1.66

21 4 0.27 1.51 0.26 1.51 0.91 0.90 0.55

Average results from both methods

Tea, dried 

leaves

Azoxystrobin 0.589

[660]

7 4 1.56 11.5 1.56 11.5 8.98 7.76 4.44

14 4 0.69 4.66 0.69 4.66 2.80 2.74 1.67

21 4 0.23 1.44 0.23 1.44 0.83 0.83 0.53

1 n = number of field trials.

2 Values based on total number of samples.

3 Values based on per-trial averages. LAFT = lowest average field trial, HAFT = highest average field trial, SD = standard 

deviation.

III. CONCLUSIONS

The tea field trials are considered scientifically acceptable. Following three foliar spray 

applications of the 20% SC formulation at a total rate of 0.589 lb ai/A (660 g ai/ha), residues of 

azoxystrobin per se, determined by averaging results from both laboratories, were 1.56-11.5, 

0.69-4.66, and 0.23-1.44 ppm, respectively, in/on samples of dried tea leaves harvested at PHIs 

of 7, 14, and 21 days. Residues of azoxystrobin decreased in dried leaves with increasing PHIs.

Acceptable methods were used for residue quantitation, and adequate storage stability data were 

submitted to support sample storage durations and conditions.
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227502

Page 10 of 10

REFERENCES

None
Azoxysrrobin [PC Code 12881 OJ/Syngenta Crop Protection, LLC 

B. 7.6 Residues Resulting from Supervised Trials 

(Annex IIA 6.3; Annex DIA 8.3) 

B.7.6.1 Residues in Target Crops 

B.7.6.1.2 Coffee 

Document ID: MRID No. 49227503 

Report: 

Guidelines: 

GLP Compliance: 

Acceptability: 

Evaluator: 

Mickelson, K. (2012) Azoxystrobin and Cyproconazole (Al 2910C)-

Magnitude of the Residues in or on Coffee: Final Report. Report/OLP 

Teclmologies Study/Task Number: TK0046957. Morse Study Number: 

67650. Unpublished study prepared by Syngenta Crop Protection, LLC. 

381 p. 

EPA OCSPP Harmonized Test Guideline 860.1500 Crop Field Trials 

(August 1996) 

PMRA Regulatory Directive DIR98-02 - Residue Chemistry Guidelines, 

Section 9 - Crop Field Trials 

PMRA Regulatory Directive DIR2010-05 -Revisions to the Residue 

Chemistry Crop Field Trial Requirements 

OECD Guideline 509 Crop Field Trial (September 2009) 

No deviations from regulatory requirements were reported which would 

have an impact on the validity of the study. 

The study is considered scientifically acceptable. The acceptability of this 

study for regulatory purposes is addressed in the fo~oming U.S. EPA 

Residue Chemistry Summary Document, DP# 41£37 . 

Steve Funk, Senior Chemist, RAB III y{ ..,, )JJ\J~ 

Note: This Data Evaluation Record (DER) was originally prepared under contract by Versar, Inc. (6850 Yersar Center, 

Springfield, VA 22151 ; submitted 9/30114). The DER has been reviewed by HED and revised to reflect current Office of 

Pesticide Programs (OPP) policies. 

EXECUTIVE SUMMARY 

Syngenta Crop Protection, LLC has submitted residue data for azoxystrobin on coffee from field 

trials conducted in Central and South America. Four coffee field trials were conducted during 

the 2011 and 2012 growing seasons in Colombia (l trial), Guatemala (1 trial), and Brazil (2 

trials). HED has determined that two triaJs conducted in Colombia are replicate trials; the above 

trial count reflects this conclusion. The submission also includes data for cyproconazole and the 

triazole metabolites.; these data are not addressed herein. 

Each trial consisted of one untreated plot and one treated plot. At all trial locations, the treated 

plot received three foliar spray applications of a J .67 lb ai/gal (200 g ai/L) suspension 

concentrate (SC) formulation of azoxystrobin (A 1291 OC). The product is a multiple active 

ingredient (MAI) formulation that also contains cyproconazole at 0.67 lb ai/gal (80 g ai/L). Each 

treated plot received three applications of azoxystrobin at 0.13 1-0.137 lb ai/Napplication (146.7-

154.0 g ai/ha/application) for total rates of 0.394-0.410 lb ai/A (441.7-459.3 g ai/ha). All 

Pa e I of8 

EPA MRID #: 49227503 
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 2 of 8

applications were made at retreatment intervals (RTIs) of 42-49 days using ground equipment in 

spray volumes of 21.38-42.58 gal/A (200.0-398.3 L/ha). A nonionic surfactant (NIS) alone or in 

conjunction with a crop oil was added to the spray mixtures for all applications. Samples of 

coffee bean “cherries” were harvested from all trials at a 14- to 15-day preharvest interval (PHI). 

Additional samples were collected from one trial at a 5-, 10-, 20-, and 25-day PHIs to assess 

residue decline. Coffee cherries were processed into green coffee beans at the field sites. 

Samples were analyzed for residues of azoxystrobin and its Z-isomer (R23010) using a high 

performance liquid chromatography method with tandem mass spectrometry detection 

(LC/MS/MS), Method RAM 305/03. Acceptable method validation and concurrent recoveries 

were reported for green coffee bean samples at fortification levels of 0.01 and 1.0 ppm, thus 

validating the method. The limit of quantitation (LOQ; determined as the lowest level of method 

validation, LLMV) was 0.01 ppm for each analyte; the LOQ for combined residues was 0.02 

ppm. 

Samples were maintained frozen at the testing facility, during shipping to the laboratory, and 

were stored frozen until analysis. The field residue samples were stored frozen a maximum of 

57 days (1.9 months) from harvest to extraction for analysis. Samples were analyzed within 0-3 

days of extraction. The available freezer storage stability data indicate that residues of 

azoxystrobin and R230310 are stable when stored frozen (<-18 °C) for up to 2 years in various 

crops including oil seed rape (DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98). 

Adequate storage stability data are therefore available to support the storage conditions and 

intervals for samples in the current trials.

Following three foliar spray applications of the 1.67 lb ai/gal SC formulation at total rates of 

0.394-0.410 lb ai/A (441.7-459.3 g ai/ha), individual sample (and per-trial average) combined 

residues of azoxystrobin and its Z-isomer (R230310) were <0.02-<0.0259 (<0.02-<0.0230) ppm 

in/on green coffee beans harvested at a 14- to 15-day PHI. Residues of the Z-isomer were below 

the LOQ (<0.01 ppm) in/on all samples.

In the residue decline trial, combined residues of azoxystrobin and R230310 declined after the 5-

day PHI to below the LOQ (<0.02 ppm) for all remaining PHIs.
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 3 of 8

I. MATERIALS AND METHODS

A. MATERIALS

Table B.7.6.1.2-1. Nomenclature for Azoxystrobin and Metabolites of Interest.

Common name Azoxystrobin

Identity

Methyl (αE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)-

benzeneacetate

CAS no. 131860-33-8

Company experimental name ICIA5504 (Zeneca), R215504 (Syngenta)

Other synonyms (if applicable) N/A

Metabolite Azoxystrobin, Z-isomer

Identity Methyl (αZ)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)-

benzeneacetate

CAS no. Not available

Company experimental name R230310

Other synonyms (if applicable) N/A

B. Study Design

1. Test Procedure

Four residue trials on coffee were conducted in Central and South America with a 1.67 lb ai/gal

(200 g ai/L) SC formulation (A12910C) during the 2011 and 2012 growing seasons in Colombia 

(1 trial), Guatemala (1 trial), and Brazil (2 trials). All trials, except for those listed in the table 

below, were separated by >20 miles and are therefore considered independent (568_Criteria for 

Independence of Trials 04/23/2013 (EPA and PMRA)). The trials separated by <20 miles have 

been assessed for independence as detailed in the table below.

Independent Trial Determination1

Crop Trial Nos. Differences Decision

Coffee -01 & -02 Same location and variety

No other differences found

Replicates

1

 All assessments are based on the replicate trial guidance presented in draft memo 568_Criteria for Independence of Trials 

04/23/2013 (EPA and PMRA).

N N

O O

CN OCH3

O

H3CO

N N

O O

CN

O OCH3

H3CO
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 4 of 8

Table B.7.6.1.2-2. Trial Numbers and Geographical Locations.

Crop No. 

Trials

NAFTA Growing Zone

Total

1 2 3 4 5 6 7 8 9 10 11 12

Coffee Sub.

Not applicable

Req.1

1OCSPP 860.1500 specifies 5 trials but does not suggest a geographic distribution.

Locations and detailed use patterns for the trials are provided in Table B.7.6.1.2-3. 

Table B.7.6.1.2-3. Study Use Pattern.

Location: City, 

Country; Year

(Trial ID)

End-use 

Product1

Method of Application/ 

Timing of Application

Volume

(gal/A)

[L/ha]

Rate per 

Application

(lb ai/A)

[g ai/ha]

Retreatment 

Interval 

(days)

Total Rate

(lb ai/A)

[g ai/ha]

Surfactant/ 

Adjuvant2

Santa Marta, 

Magdalena, 

Colombia; 2011

(TK0046957-01)3

1.67 lb ai/gal 

SC

1. Foliar spray; BBCH 75 25.70

[240.4]

0.131

[146.7]

-- 0.394

[441.7]

NIS & crop 

oil

2. Foliar spray; BBCH 77 25.83

[241.6]

0.132

[147.7]

42

3. Foliar spray; BBCH 81 25.85

[241.8]

0.131

[147.3]

42

Santa Marta, 

Magdalena, 

Colombia; 2011

(TK0046957-02)3

1.67 lb ai/gal 

SC

1. Foliar spray; BBCH 75 25.86

[241.9]

0.132

[147.6]

-- 0.395

[442.8]

NIS & crop 

oil

2. Foliar spray; BBCH 77 25.83

[241.6]

0.131

[147.4]

42

3. Foliar spray; BBCH 81 25.90

[242.3]

0.132

[147.8]

42

Santa Rosa, 

Guatemala; 2011

(TK0046957-03)

1.67 lb ai/gal 

SC

1. Foliar spray; BBCH 75 21.38

[200.0]

0.134

[150.0]

-- 0.403

[452.3]

NIS

2. Foliar spray; BBCH 81 21.69

[202.9]

0.136

[152.2]

42

3. Foliar spray; BBCH 85 21.39

[200.1]

0.134

[150.1]

44

Santo Antonio Do 

Jardim, Brazil; 

2012

(TK0046957-04)

1.67 lb ai/gal 

SC

1. Foliar spray; BBCH 77 42.58

[398.3]

0.135

[151.9]

-- 0.403

[451.7]

NIS

2. Foliar spray; BBCH 80 42.20

[394.8]

0.133

[149.5]

45

3. Foliar spray; BBCH 85 41.84

[391.4]

0.134

[150.3]

47

Dois Córregos, 

Brazil; 2012

(TK0046957-05)

1.67 lb ai/gal 

SC

1. Foliar spray; BBCH 77 40.69

[380.6]

0.137

[154.0]

-- 0.410

[459.3]

NIS

2. Foliar spray; BBCH 80 40.08

[374.9]

0.135

[151.8]

43

3. Foliar spray; BBCH 85 40.54

[379.2]

0.137

[153.5]

49

1

 A multiple active ingredient (MAI) suspension concentrate (SC) formulation (A12910C) containing 1.67 lb ai/gal (200 g ai/L) 

azoxystrobin and 0.67 lb ai/gal (80 g ai/L) cyproconazole.

2 NIS = non-ionic surfactant.

3Considered one trial (dependent)

Coffee plants were grown and maintained according to typical agricultural practices. Irrigation 

was not used. No unusual weather conditions were reported during the study.
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 5 of 8

Sample Handling and Preparation

At all test sites, a single control and duplicate treated samples of coffee cherries were harvested 

14-15 days after the last application. Additional samples were also collected at PHIs of 5, 10, 

20, and 25 days in one trial to assess residue decline. Coffee cherries were processed into green 

coffee beans at the field sites prior to shipment to the analytical laboratory. For the Colombia 

and Guatemala trials, the process for producing dry green coffee beans included: (i) removing 

the skin of the berry and some of the pulp by mechanically pressing the fruit through a screen in 

a water batch; (ii) removal of the remaining pulp using a fermentation and washing process; (iii) 

drying using forced air or sun drying; and (iv) hand removal of the thin parchment layer that 

remains after drying. For the Brazil trials, the process for producing dry green coffee beans 

included: (i) sun drying the whole berry immediately after collection; (ii) mechanically peeling 

the dried outer layer; and (iii) manual cleaning using a sieve and forced air. The samples were 

placed in frozen storage (temperature unspecified) at the field sites after collection (interval 

between collection and freezing not reported). All samples were shipped frozen via air courier 

with dry ice within 8-32 days of collection to the analytical laboratory, Morse Laboratories, LLC 

(Sacramento, CA), where they were maintained frozen (<-20 °C) prior to analysis. In 

preparation for analysis, samples were homogenized.

2. Description of Analytical Procedures

Samples were analyzed for residues of azoxystrobin and its Z-isomer (R230310) using an 

LC/MS/MS method, Method RAM 305/03. A brief description of the method was included in 

the submission.

Briefly, samples were extracted with acetonitrile (ACN):water (90:10, v:v). After centrifugation, 

the extract was cleaned up on a C18 solid phase extraction column for analysis by LC/MS/MS.

The LOQ (determined as the LLMV) was 0.01 ppm for each analyte; the LOQ for combined 

residues was 0.02 ppm. The limit of detection (LOD) was not reported.

II. RESULTS AND DISCUSSION

Method performance was evaluated during method validation and by use of concurrent recovery 

samples by fortifying green coffee beans at 0.01-1.0 ppm. Recoveries were within the 

acceptable range of 70-120%; therefore, the method was considered valid for the analysis of

azoxystrobin and R230310 in green coffee beans (Table B.7.6.1.2-4). The fortification levels 

bracketed the measured residues. Concurrent recoveries were corrected for apparent residues in 

controls.

The detector response was linear (coefficient of determination, r2 ≥0.9962) within the range of 

0.05-5.0 ng/mL. Representative chromatograms of control samples, fortified samples and treated 

samples were provided. The control chromatograms generally had no peaks of interest above the 

chromatographic background. The fortified sample chromatograms contained only the analyte of 

interest, and peaks were symmetrical and well defined. Apparent residues in controls were 
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 6 of 8

below the LOQ (<0.01 ppm) for both analytes. The reported residue values were not corrected 

for apparent residues in controls.

Table B.7.6.1.2-4. Summary of Method Validation and Procedural/Concurrent 

Recoveries of Azoxystrobin and its Z-isomer (R230310) from Green Coffee Beans.

Matrix Analyte Fortification 

Level (ppm)

Sample size 

(n)

Recoveries1

(%)

Mean ± Std. Dev.

(%)

Method Validation

Coffee,

green bean

Azoxystrobin 0.01-1.0 6 96-106 102 ± 3.4

R230310 0.01-1.0 6 104-115 109 ± 4.8

Concurrent Recovery

Coffee,

green bean

Azoxystrobin 0.01-1.0 8 87-116 102 ± 8.8

R230310 0.01-1.0 8 89-118 103 ± 8.3

1 Concurrent recoveries were corrected for apparent residues in controls.

The field residue samples were stored frozen a maximum of 57 days (1.9 months) from harvest 

to extraction for analysis (Table B.7.6.1.2-5). Samples were analyzed within 0-3 days of 

extraction. The available freezer storage stability data indicate that residues of azoxystrobin and 

R230310 are stable when stored frozen (<-18 °C) for up to 2 years in various crops including oil 

seed rape (DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98).

Table B.7.6.1.2-5. Summary of Storage Conditions.

Matrix Storage Temperature 

(°C)

Actual Storage Duration1Interval of Demonstrated Storage Stability

Coffee, green bean -20 31-57 days

(1.0-1.9 months)

Residues of azoxystrobin and R230310 are stable for 

up to 2 years in various crops including oil seed rape 

stored frozen (<-18 °C).2

1

Interval from harvest to extraction. Samples were analyzed within 0-3 days of extraction.

2 DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98

The results from the submitted field trials are presented in Tables B.7.6.1.2-6 and B.7.6.1.2-7. 

Following three foliar spray applications of the 1.67 lb ai/gal SC formulation at total rates of

0.394-0.410 lb ai/A (441.7-459.3 g ai/ha), individual sample (and per-trial average) combined 

residues of azoxystrobin and its Z-isomer (R230310) were <0.02-<0.0259 (<0.02-<0.0230) ppm

in/on green coffee beans harvested at a 14- to 15-day PHI. Residues of the Z-isomer were below 

the LOQ (<0.01 ppm) in/on all samples.

In the residue decline trial, combined residues of azoxystrobin and R230310 declined after the 5-

day PHI to below the LOQ (<0.02 ppm) for all remaining PHIs.
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 7 of 8

Table B.7.6.1.2-6. Residue Data from Coffee Field Trials with Azoxystrobin.

1

Location: City, Country; 

Year

(Trial ID)

Coffee 

Variety

Matrix Rate

(lb ai/A)

[g ai/ha]

PHI

(days)

Residues2(ppm) [Average]

Azoxystrobin R230310 Combined3

Santa Marta, Magdalena, 

Colombia; 2011

(TK0046957-01 and -02)

Castillo Green 

coffee 

bean

0.394-

0.395

[441.7-

442.8]

15 <0.01, <0.01, 

<0.01, <0.01

[<0.01]

<0.01, ND, ND, 

ND

[<0.01]

<0.02, <0.02, 

<0.02, <0.02

[<0.02]

Santa Marta, Magdalena, 

Colombia; 2011

(TK0046957-02)

(Decline trial)

Castillo Green 

coffee 

bean

0.395

[442.8]

5 0.0181, 0.0194

[0.0188]

<0.01, <0.01

[<0.01]

<0.0281, 

<0.0294

[<0.0288]

10 <0.01, <0.01

[<0.01]

ND, ND

[<0.01]

<0.02, <0.02

[<0.02]

20 <0.01, <0.01

[<0.01]

ND, ND

[<0.01]

<0.02, <0.02

[<0.02]

25 <0.01, <0.01

[<0.01]

ND, ND

[<0.01]

<0.02, <0.02

[<0.02]

Santa Rosa, Guatemala; 

2011

(TK0046957-03)

Bourbon Green 

coffee 

bean

0.403

[452.3]

14 <0.01, 0.0159

[<0.0130]

ND, <0.01

[<0.01]

<0.02, <0.0259

[<0.0230]

Santo Antonio Do Jardim, 

Brazil; 2012

(TK0046957-04)

Obatã Green 

coffee 

bean

0.403

[451.7]

14 <0.01, 0.0107

[<0.0104]

ND, ND

[<0.01]

<0.02, <0.0207

[<0.0204]

Dois Córregos, Brazil; 

2012

(TK0046957-05)

Tupi Green 

coffee 

bean

0.410

[459.3]

14 <0.01, 0.0102

[<0.0101]

ND, ND

[<0.01]

<0.02, <0.0202

[<0.0201]

1 A multiple active ingredient (MAI) suspension concentrate (SC) formulation (A12910C) containing 1.67 lb ai/gal (200 g ai/L) 

azoxystrobin and 0.67 lb ai/gal (80 g ai/L) cyproconazole was used.

2 The LOQ was 0.01 ppm for each analyte. The LOD was not reported. ND = none detected as reported by the petitioner; no 

observable chromatographic response. Combined residues and per-trial averages were calculated by the study reviewer using the 

LOQ for all residues reported as <LOQ.

3 Combined residues of azoxystrobin and its Z-isomer (R230310).

Table B.7.6.1.2-7. Summary of Residues from Coffee Field Trials with Azoxystrobin.

Crop Matrix Total Application Rate

(lb ai/A)

[g ai/ha]

PHI 

(days)

n

1 Residues Azoxystrobin2

(ppm)

Min.3 Max.3 LAFT4 HAFT4 Median4 Mean4 SD4

Coffee, green bean 0.394-0.410

[441.7-459.3]

14-15 4 <0.02 <0.0259 <0.02 <0.0230 0.0202 0.0209 0.0014

1 n = number of field trials.

2 Combined residues of azoxystrobin and its Z-isomer (R230310).

3 Values based on total number of samples.

4 Values based on per-trial averages. LAFT = lowest average field trial, HAFT = highest average field trial, SD = standard 

deviation. For computation of the LAFT, HAFT, median, mean, and standard deviation, values <LOQ are assumed to be at the 

LOQ (0.01 ppm).
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 8 of 8

III. CONCLUSIONS

The coffee field trials are considered scientifically acceptable. Following three foliar spray 

applications of the 1.67 lb ai/gal SC formulation at total rates of 0.394-0.410 lb ai/A (441.7-

459.3 g ai/ha), individual sample (and per-trial average) combined residues of azoxystrobin and 

its Z-isomer (R230310) were <0.02-<0.0259 (<0.02-<0.0230) ppm in/on green coffee beans 

harvested at a 14- to 15-day PHI. Residues of the Z-isomer were below the LOQ (<0.01 ppm) 

in/on all samples. In the residue decline trial, combined residues of azoxystrobin and R230310 

declined after the 5-day PHI to below the LOQ (<0.02 ppm) for all remaining PHIs.

An acceptable method was used for residue quantitation, and adequate storage stability data are 

available to support sample storage durations and conditions for all analytes.

REFERENCES

DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98
Azoxystrobin [PC Code 1288 1 OJ/Syngenta Crop Protection, LLC 

B.7.7 

B.7.7.1 

B.7.7.2 

Effects of Industrial Processing and/or Household Preparation 

(Annex HA 6.5; Annex IHA 8.5) 

Nature of the Residue 

(Annex HA 6.5.1; Annex IHA 8.5.1) - Not a data requirement in North America 

Distribution of the Residue in Peel/Pulp 

(Annex HA 6.5.2; Annex IHA 8.5.2) 

To be included if available. 

B.7.7.3 Magnitude of Residues on Set of Representative Processes 

(Annex HA 6.5.3; Annex IIIA 8.5.3) 

B.7.7.3.1 Coffee 

Document ID: MRID No. 49227503 

Report: Mickelson, K. (2012) Azoxystrobin and Cyproconazole (A 1291 OC) -

Magnitude of the Residues in or on Coffee: Final Report. Report/OLP 

Technologies Study/Task Number: TK0046957. Morse Study Number: 

67650. Unpublished study prepared by Syngenta Crop Protection, LLC. 

381 p. 

Guidelines: EPA OCSPP Harmonized Test Guideline 860.1520 Processed Food/Feed 

(August 1996) 

PMRA Regulatory Directive DIR98-02 - Residue Chemistry Guidelines, 

Section 10 - Processed Food/Feed 

OECD Guideline 508 Magnitude of the Pesticide Residues in Processed 

Commodities (October 2008) 

GLP Compliance: No deviations from regulatory requirements were reported which would 

have an impact on the validity of the study. 

Acceptability: The study is considered scientifically acceptable. The acceptability of this 

study for regulatory purposes is addressed in the forthcoming U.S. EPA 

Residue Chemistry Summary Document, QP~f,18374. 

Evaluator: Steve Funk, Senior Chemist, RAB III ;f C{' 0 .,;)_ 

Note: This Data Evaluation Record (DER) was originally prepared under contract by Versar, lnc. (6850 Versar Center, 

Springfield, VA 22151; submitted 9/30/14). The DER has been reviewed by HED and revised to reflect current Office of 

Pesticide Programs (OPP) policies. 

EXECUTIVE SUMMARY 

Syngenta Crop Protection, LLC has submitted a processing study with azoxystrobin on coffee. 

In one trial conducted in Guatemala during the 2011 growing season, a treated plot received 

three foliar spray applications of a 1.67 lb ai/gal (200 g ai/L) suspension concentrate (SC) 

formulation of azoxystrobin (A 1291 OC). The product is a multiple active ingredient (MAI) 

formulation that also contains cyproconazole at 0.67 lb ai/gal (80 g ai/L). Data pertaining to 

EPA MRID #: 49227503 

Page I of8 
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 2 of 8

cyproconazole are not addressed herein. The treated plot received three applications of 

azoxystrobin at an exaggerated rate of 0.6651-0.6794 lb ai/A/application (745.6-761.7 g 

ai/ha/application) for a total rate of 2.014 lb ai/A (2258 g ai/ha). The application rate used in the 

study was ~5x that used in the corresponding field trials. Applications were made at retreatment 

intervals (RTIs) of 42-44 days using ground equipment in spray volumes of 21.25-21.71 gal/A 

(198.8-203.1 L/ha). A nonionic surfactant (NIS) was added to the spray mixtures for all 

applications. Samples of coffee bean “cherries” were harvested at a 14-day preharvest interval 

(PHI). Coffee cherries were processed into green coffee beans at the field sites, and the green 

coffee bean samples were processed into roasted coffee beans and instant coffee at GLP 

Technologies (Navasota, TX) using simulated commercial practices. Adequate descriptions of 

the processing procedures were provided, including material balance summaries.

Samples were analyzed for residues of azoxystrobin and its Z-isomer (R23010) using a high 

performance liquid chromatography method with tandem mass spectrometry detection 

(LC/MS/MS), Method RAM 305/03. Acceptable method validation and concurrent recoveries 

were reported for samples of green coffee bean, roasted coffee bean, and instant coffee at 

fortification levels of 0.01-1.0 ppm, thus validating the method. The limit of quantitation (LOQ; 

determined as the lowest level of method validation, LLMV) was 0.01 ppm for each analyte. 

Samples were maintained frozen at the testing facility and remained frozen during shipping and 

storage prior to processing and analysis. Processing took place within 51 days of collection. The 

maximum storage intervals from harvest/processing to extraction were 71 and 28 days (2.6 and 

0.9 months), respectively, for green coffee bean and the processed commodities of roasted coffee 

beans and instant coffee. Samples were analyzed within 3 days of extraction. The available 

freezer storage stability data indicate that residues of azoxystrobin and R230310 are stable when 

stored frozen (<-18 °C) for up to 2 years in various crops including oil seed rape (DP# 248887, 

D. Dotson, M. Doherty, and Y. Donovan, 10/14/98). These data are acceptable to support the 

storage conditions and durations of the green coffee bean RAC samples from the submitted

study. No storage stability data are required for roasted coffee bean and instant coffee because

samples were analyzed within ~30 days of processing.

In samples harvested at a 14-day PHI following the last of three foliar spray applications of the 

1.67 lb ai/gal SC formulation at an exaggerated total rate of 2.014 lb ai/A (2258 g ai/ha), average 

residues of azoxystrobin were below the LOQ (<0.01 ppm) in/on green coffee bean (RAC), 

<0.0108 ppm in dry roasted coffee, and <0.0168 ppm in instant coffee. A comparison of the 

residues in/on green coffee bean with those in processed coffee fractions indicated that residues 

of azoxystrobin may concentrate in dry roasted coffee (processing factor of 1.1x) and instant 

coffee (1.7x). Corresponding residues of the Z-isomer (R230310) were below the LOQ (<0.01

ppm) in/on all samples of green coffee bean and processed commodities; therefore, processing 

factors could not be calculated. 

The observed processing factors do not exceed the theoretical concentration factors of 1.2x for 

roasted coffee bean and 4.4x for instant coffee [based on separation into components; OCSPP 

860.1520, Table 3].
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 3 of 8

I. MATERIALS AND METHODS

A. MATERIALS

Table B.7.7.3.1-1. Nomenclature for Azoxystrobin and Metabolites of Interest.

Common name Azoxystrobin

Identity

Methyl (αE)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)-

benzeneacetate

CAS no. 131860-33-8

Company experimental name ICIA5504 (Zeneca), R215504 (Syngenta)

Other synonyms (if applicable) N/A

Metabolite Azoxystrobin, Z-isomer

Identity Methyl (αZ)-2-[[6-(2-cyanophenoxy)-4-pyrimidinyl]oxy]-α-(methoxymethylene)-

benzeneacetate

CAS no. Not available

Company experimental name R230310

Other synonyms (if applicable) N/A

B. Study Design

1. Test Procedure

Location and detailed use pattern for the trial is provided in Table B.7.7.3.1-2. 

Table B.7.7.3.1-2. Study Use Pattern.

Location: City, 

Country; Year

(Trial ID)

End-use 

Product1

Method of Application/ 

Timing of Application

Volume

(gal/A)

[L/ha]

Rate per 

Application

(lb ai/A)

[g ai/ha]

Retreatment 

Interval 

(days)

Total Rate

(lb ai/A)

[g ai/ha]

Surfactant/ 

Adjuvant2

Santa Rosa, 

Guatemala; 2011

(TK0046957-03)

1.67 lb 

ai/gal SC

1. Foliar spray; BBCH 

75

21.25

[198.8]

0.6651

[745.6]

-- 2.014

[2258]

NIS

2. Foliar spray; BBCH 

81

21.71

[203.1]

0.6794

[761.7]

42

3. Foliar spray; BBCH 

85

21.39

[200.1]

0.6695

[750.6]

44

1 A multiple active ingredient (MAI) suspension concentrate (SC) formulation (A12910C) containing 1.67 lb ai/gal (200 g ai/L) 

azoxystrobin and 0.67 lb ai/gal (80 g ai/L) cyproconazole.

2 NIS = non-ionic surfactant.

N N

O O

CN OCH3

O

H3CO

N N

O O

CN

O OCH3

H3CO
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 4 of 8

Sample Handling and Preparation

Single control and treated bulk samples (~25 kg) of coffee bean cherries were collected from 

each plot. Coffee cherries were processed into green coffee beans at the field site prior to 

shipment to the processing facilities. The process for producing dry green coffee beans included: 

(i) removing the skin of the berry and some of the pulp by mechanically pressing the fruit 

through a screen in a water batch; (ii) removal of the remaining pulp using a fermentation and 

washing process; (iii) drying using forced air or sun drying; and (iv) hand removal of the thin 

parchment layer that remains after drying. Bulk green coffee bean samples were shipped frozen

on dry ice 8 days after harvest to the processing facility, GLP Technologies (Navasota, TX) for 

processing into roasted coffee bean and instant coffee. At the processor, samples were stored 

frozen (≤10 °F) prior to processing. Processing was completed within 51 days of harvest, and 

the samples were returned to frozen storage for up to 15 days prior to shipment via FedEx on dry 

ice to the analytical laboratory, Morse Laboratories, LLC (Sacramento, CA), where they were 

maintained frozen (-20 °C) prior to analysis.

Sample Processing

The processing procedures simulated commercial operations of coffee production as closely as 

possible to generate the required fraction of green coffee bean (RAC) and the processed 

fractions, with some variations to commercial methods. Adequate descriptions of the processing 

procedures were provided, including material balance summaries. A processing flowchart for 

coffee processed fractions, copied without alteration from MRID 49227503, is presented in 

Figure B.1.
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 5 of 8

FIGURE B.1. Processing Flowchart for Coffee.

2. Description of Analytical Procedures

Samples were analyzed for residues of azoxystrobin and its Z-isomer (R230310) using an 

LC/MS/MS method, Method RAM 305/03. A brief description of the method was included in 

the submission.

Briefly, samples were extracted with acetonitrile (ACN):water (90:10, v:v). After centrifugation, 

the extract was cleaned up on a C18 solid phase extraction column for analysis by LC/MS/MS.

The LOQ (determined as the LLMV) was 0.01 ppm for each analyte; the limit of detection 

(LOD) was not reported.
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 6 of 8

II. RESULTS AND DISCUSSION

Method performance was evaluated during method validation and by use of concurrent recovery 

samples by fortifying green coffee beans, roasted coffee beans, and instant coffee at 0.01-1.0 

ppm. Recoveries were within the acceptable range of 70-120%; therefore, the method was 

considered valid for the analysis of azoxystrobin and R230310 in green coffee beans, roasted 

coffee beans, and instant coffee (Table B.7.7.3.1-3). The fortification levels bracketed the 

measured residues. Concurrent recoveries were corrected for apparent residues in controls.

The detector response was linear (coefficient of determination, r2 ≥0.9962) within the range of 

0.05-5.0 ng/mL. Representative chromatograms of control samples, fortified samples and treated 

samples were provided. The control chromatograms generally had no peaks of interest above the 

chromatographic background. The fortified sample chromatograms contained only the analyte of 

interest, and peaks were symmetrical and well defined. Apparent residues in controls were 

below the LOQ (<0.01 ppm) for both analytes. The reported residue values were not corrected 

for apparent residues in controls.

Table B.7.7.3.1-3. Summary of Method Validation and Procedural/Concurrent 

Recoveries of Azoxystrobin and its Z-isomer (R230310) from Coffee Matrices.

Matrix Analyte Fortification 

Level (ppm)

Sample size 

(n)

Recoveries1

(%)

Mean ± Std. Dev.2

(%)

Method Validation

Coffee,

green bean

Azoxystrobin 0.01-1.0 6 96-106 102 ± 3.4

R230310 0.01-1.0 6 104-115 109 ± 4.8

Roasted coffee 

beans

Azoxystrobin 0.01-1.0 6 72-85 81 ± 5.0

R230310 0.01-1.0 6 73-86 81 ± 5.8

Instant coffee Azoxystrobin 0.01-1.0 6 87-98 94 ± 3.9

R230310 0.01-1.0 6 77-97 87 ± 9.9

Concurrent Recovery

Coffee,

green bean

Azoxystrobin 0.01-1.0 8 87-116 102 ± 8.8

R230310 0.01-1.0 8 89-118 103 ± 8.3

Roasted coffee 

beans

Azoxystrobin 0.01-1.0 2 95-107 101

R230310 0.01-1.0 2 96-110 103

Instant coffee Azoxystrobin 0.01-1.0 2 76-94 85

R230310 0.01-1.0 2 72-92 82

1 Concurrent recoveries were corrected for apparent residues in controls.

2 Standard deviation is not calculated for sample sizes <3.

The maximum storage intervals for samples were 71 and 28 days (2.6 and 0.9 months), 

respectively, for green coffee bean and the processed commodities of roasted coffee beans and 

instant coffee from harvest/processing to extraction (Table B.7.7.3.1-4). Samples were analyzed 

within 3 days of extraction. Processing took place within 51 days of collection.

The available freezer storage stability data indicate that residues of azoxystrobin and R230310 

are stable when stored frozen (<-18 °C) for up to 2 years in various crops including oil seed rape 

(DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98). These data are acceptable to 

support the storage conditions and durations of the green coffee bean RAC samples from the 
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 7 of 8

submitted study. No storage stability data are required for roasted coffee bean and instant coffee 

because these samples were analyzed within ~30 days of processing.

Table B.7.7.3.1-4. Summary of Storage Conditions1.

Matrix Storage Temperature Actual Storage 

Duration

Interval of Demonstrated Storage Stability

Coffee, green bean 

(RAC)

Frozen at field site;

≤10 °F at processor;

-20 °C at analytical 

laboratory

71 days (2.6 months) Residues of azoxystrobin and R230310 are stable 

for up to 2 years in various crops including oil 

seed rape stored frozen (<-18 °C).2

Dry roasted coffee bean 28 days (0.9 months) Storage stability data are not required for 

processed coffee commodities as these samples 

were analyzed within ~30 days of processing.

Instant coffee 21 days (0.7 months)

1

Interval from harvest/processing to extraction. Samples were analyzed within 1-3 days of extraction.

2 DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98

Residues found in samples and processing factors are given in Table B.7.7.3.1-5. In samples 

harvested at a 14-day PHI following the last of three foliar spray applications of the 1.67 lb ai/gal 

SC formulation at a 5X exaggerated total rate of 2.014 lb ai/A (2258 g ai/ha), average residues of 

azoxystrobin were below the LOQ (<0.01 ppm) in/on green coffee bean (RAC), <0.0108 ppm in 

dry roasted coffee, and <0.0168 ppm in instant coffee. A comparison of the residues in/on green 

coffee bean with those in processed coffee fractions indicated that residues of azoxystrobin may 

concentrate in dry roasted coffee (processing factor of 1.1x) and instant coffee (1.7x). 

Corresponding residues of the Z-isomer (R230310) were below the LOQ (<0.01 ppm) in/on all 

samples of green coffee bean and processed commodities; therefore, processing factors could not 

be calculated. 

The observed processing factors do not exceed the theoretical concentration factors of 1.2x for 

roasted coffee bean and 4.4x for instant coffee [based on separation into components; OCSPP 

860.1520, Table 3].

Table B.7.7.3.1-5. Residue Data from Coffee Processing Study with Azoxystrobin.

Commodity Analyte Residues1

(ppm)[Average]

Processing Factor2 Median Processing 

Factor

Coffee bean

(prior to processing)

Azoxystrobin <0.01, <0.01, <0.01

[<0.01]

-- Not applicable

R230310 ND, ND, ND

[<0.01]

--

Dry roasted coffee Azoxystrobin 0.0115, <0.01

[<0.0108]

>1.1x

R230310 ND, ND

[<0.01]

NC3

Instant coffee Azoxystrobin <0.01, 0.0236

[<0.0168]

>1.7x

R230310 ND, ND

[<0.01]

NC

1 The LOQ was 0.01 ppm for each analyte. The LOD was not reported. ND = none detected as reported by the petitioner; no 

observable chromatographic response. 

2 Processing Factor = [Measured residue for analyte in the processed fraction] / [Measured residue for analyte in the RAC]

3 NC = Not calculated; residues were below the LOQ in both the RAC and processed fraction
Azoxystrobin [PC Code 128810]/Syngenta Crop Protection, LLC

EPA MRID #: 49227503

Page 8 of 8

III. CONCLUSIONS

The coffee processing study is considered scientifically acceptable. In samples harvested at a 

14-day PHI following the last of three foliar spray applications of the 1.67 lb ai/gal SC 

formulation at an exaggerated total rate of 2.014 lb ai/A (2258 g ai/ha), average residues of 

azoxystrobin were below the LOQ (<0.01 ppm) in/on green coffee bean (RAC), <0.0108 ppm in 

dry roasted coffee, and <0.0168 ppm in instant coffee. A comparison of the residues in/on green 

coffee bean with those in processed coffee fractions indicated that residues of azoxystrobin may 

concentrate in dry roasted coffee (processing factor of 1.1x) and instant coffee (1.7x). 

Corresponding residues of the Z-isomer (R230310) were below the LOQ (<0.01 ppm) in/on all 

samples of green coffee bean and processed commodities; therefore, processing factors could not 

be calculated. 

The observed processing factors do not exceed the theoretical concentration factors of 1.2x for 

roasted coffee bean and 4.4x for instant coffee [based on separation into components; OCSPP 

860.1520, Table 3].

An acceptable method was used for residue quantitation, and adequate storage stability data are 

to support sample storage durations and conditions for all analytes.

REFERENCES

DP# 248887, D. Dotson, M. Doherty, and Y. Donovan, 10/14/98