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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

OFFICE OF CHEMICAL SAFETY AND

 POLLUTION PREVENTION

MEMORANDUM

 

Date: 23-October-2014 

Subject: Metconazole. Petition for the Establishment of Permanent Tolerances and 

Registration for Use on the Pea and Bean, Dried Shelled, except Soybean, Subgroup

6C and the Sunflower Subgroup 20B; Expansion of the Canola Tolerance to the 

Rapeseed Subgroup 20A; and Conversion of the Established Stone Fruit and Tree Nut 

Crop Groups to the Stone Fruit Group 12-12 and the Tree Nut Group 14-12.

Summary of Analytical Chemistry and Residue Data.

PC Code: 125619 DP Barcode: D419223

Decision No.: 487580 Registration No.: 59639-147

Petition No.: 4E8244 Regulatory Action: Section 3 Registration

Risk Assessment Type: NA Case No.: NA

TXR No.: NA CAS No.: 125116-23-6 

MRID No.: See Below 40 CFR: 180.617

From: Nancy Dodd, Chemist

Risk Assessment Branch III (RAB3)

Health Effects Division (HED; 7509P)

Through: Steve Funk, Senior Chemist

RAB3/HED (7509P)

To: Barbara Madden, RM#05

Registration Division (7505P)

 
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Summary of Submitted Residue Chemistry Studies

OCSPP 860 

Series Guideline

MRID Number Title

860.1500 49297801 Corley, J. (2013) Metconazole: Magnitude of the Residue on Bean (Dry). 

Laboratory Project ID: 10388.10-JRF02. Unpublished study prepared by 

IR-4 Project. 201 p.

860.1500 49297802 Corley, J. (2013) Metconazole: Magnitude of the Residue on Pea (Dry). 

Laboratory Project ID: 10389.10-JRF03. Unpublished study prepared by 

IR-4 Project. 173 p.

860.1500

860.1520

49297803 Corley, J. (2013) Metconazole: Magnitude of the Residue on Sunflower. 

Laboratory Project ID: 10390.10-JRF01. Unpublished study prepared by 

IR-4 Project. 237 p.
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Table of Contents

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

2.0 Regulatory Recommendations............................................................................................ 8

2.1 Data Deficiencies/Data Needs.......................................................................................... 9

2.2 Tolerance Considerations................................................................................................. 9

2.2.1 Enforcement Analytical Method............................................................................... 9

2.2.2 Recommended Tolerances........................................................................................ 9

2.2.3 Revisions to Petitioned-For Tolerances.................................................................. 10

2.2.4 International Harmonization ................................................................................... 10

3.0 Introduction....................................................................................................................... 11

3.1 Chemical Identity ........................................................................................................... 12

3.2 Physical/Chemical Characteristics................................................................................. 12

3.3 Pesticide Use Pattern/Directions for Use (860.1200)..................................................... 14

4.0 Metabolite/Degradate Residue Profile.............................................................................. 19

4.1 Nature of the Residue..................................................................................................... 19

4.1.1 Summary of Plant Metabolism (860.1300)............................................................. 19

4.1.2 Summary of Livestock Metabolism (860.1300)..................................................... 20

4.1.3 Summary of Confined Rotational Crops (860.l850)............................................... 20

4.1.4 Summary of Metabolites and Degradates............................................................... 21

4.2 Comparison of Metabolic Pathways .............................................................................. 21

4.3 Residues of Concern Summary and Rationale............................................................... 22

5.0 Residue Profile.................................................................................................................. 24

5.1 Residue Analytical Methods (860.1340)........................................................................ 24

5.1.1 Data Collection Methods ........................................................................................ 24

5.1.2 Multi-Residue Methods (860.1360)........................................................................ 25

5.1.3 Tolerance Enforcement Methods............................................................................ 26

5.1.4 Submittal of Analytical Reference Standards (860.1650) ...................................... 28

5.2 Storage Stability (860.1380) .......................................................................................... 29

5.3 Residue Data .................................................................................................................. 32

5.3.1 Crop Field Trials (860.1500) .................................................................................. 32

5.3.2 Field Rotational Crops (860.1900) ......................................................................... 38

5.3.3 Processed Food and Feed (860.1520)..................................................................... 39

5.3.4 Meat, Milk, Poultry and Eggs (860.1480) .............................................................. 42
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5.3.4.1 Dietary Burden ................................................................................................ 44

5.3.4.2 Estimated Secondary Residues in Livestock ................................................... 45

5.3.5 Food Handling (860.1460)...................................................................................... 46

5.3.6 Water, Fish, and Irrigated Crops (860.1400).......................................................... 46

5.4 Food Residue Profile...................................................................................................... 46

6.0 Tolerance Derivation ........................................................................................................ 47

Appendix A. Tabular Summary of Metabolites........................................................................... 50

Appendix B. Field Trial Geographic Distribution ....................................................................... 52

Appendix C. International Residue Limits Table ........................................................................ 53

Appendix D. OECD MRL Calculation Procedure Inputs/Outputs.............................................. 55

 
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1.0 Executive Summary

Metconazole [5-[(4-chlorophenyl)methyl]-2,2-dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl)cyclopentanol] is a broad-spectrum triazole fungicide that works systemically by

preventing spore formation and inhibiting mycelial growth. Metconazole acts primarily as an 

inhibitor of ergosterol biosynthesis, thereby interfering with synthesis of fungal cell membranes

and providing systemic seed and seedling protection. 

The Interregional Research Project No. 4 (IR-4), on behalf of the IR-4 Project and the 

Agricultural Experiment Stations of Montana, South Dakota, North Dakota, and Colorado (dry

bean), Montana, South Dakota, Idaho, and North Dakota (dry pea), and Kansas, Montana, South

Dakota and North Dakota (sunflower), requested the establishment of permanent tolerances and 

registration for use on the pea and bean, dried shelled, except soybean, subgroup 6C, and the 

sunflower subgroup 20B; expansion of the canola tolerance to the rapeseed subgroup 20A; and 

conversion of the established stone fruit crop group 12 and tree nut crop group 14 to the stone 

fruit crop group 12-12 and the tree nut crop group 14-12. 

Proposed Uses: Metconazole 50 WDG Fungicide (EPA Reg. No. 59639-147) is a waterdispersible granule formulation containing 50% active ingredient (ai). It is to be applied to crops 

in the pea and bean, dried shelled, except soybean, subgroup 6C; the sunflower subgroup 20B; 

the rapeseed subgroup 20A; the stone fruit crop group 12-12, and the tree nut crop group 14-12. 

Applications are to be made as broadcast foliar sprays in sufficient water for thorough coverage 

using ground equipment (including chemigation) or aerial equipment. Depending on the crop 

and the targeted fungal disease, single application rates range from 0.0625-0.125 lb ai/A. 

Depending on the crop, a maximum of one to four applications can be made with minimum 

retreatment intervals (RTIs) ranging from 7 to 14 days except for pecan (interval not specified) 

and pistachio (2-3 week interval); the yearly application rates range from 0.125 to 0.500 lb ai/A.

Preharvest intervals (PHIs) range from 14-35 days. Immediate plant-back is allowed for barley, 

corn, cotton, oat, peanut, rye, soybean, sugar beet, triticale, wheat, and those crops listed on the 

label. A 30-day plant-back interval (PBI) is required for Brassica leafy vegetables and leafy

vegetables. A 120-day PBI applies to other crops.

Nature of the Residue in Primary Plants: The nature of the residue in crops in the pea and bean, 

dried shelled, except soybean, subgroup 6C; the sunflower subgroup 20B, the rapeseed subgroup 

20A, the stone fruit crop group 12-12, and the tree nut crop group 14-12 is adequately 

understood based on metabolism studies on banana, canola, mandarin, pea, and wheat. The 

metabolism of metconazole was similar in all crops investigated. Metconazole (parent) is the 

residue of concern for the tolerance expression for primary and rotational crops. Metconazole is 

the residue of concern for risk assessment purposes in primary and rotational crops except for 

cereal grains; the residues of concern for risk assessment in cereal grains (as both primary and 

rotational crops) are metconazole and the metabolite M11. (See Section 4.3 and Appendix A.)

HED also has concern for residues of free 1,2,4-triazole and its conjugates, triazolylalanine (TA) 

and triazolylacetic acid (TAA), in plants as a result of the use of metconazole. However, 

because separate endpoints for these compounds have been established, exposure and risks from 

free triazole and its conjugates will be addressed separately.
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Nature of the Residue in Livestock: The nature of the residue in livestock (ruminants and 

poultry) is adequately understood. The residue of concern for the tolerance expression in 

livestock commodities is metconazole. The residues of concern in livestock for purposes of the 

risk assessment are metconazole and metabolites M1 (free and its glucuronic acid conjugate), 

M12, and M31 (free and its glucuronic acid conjugate). (See Section 4.3 and Appendix A.)

HED also has concern for residues of 1,2,4-triazole, TA, and TAA in livestock as a result of the 

use of metconazole. However, because separate endpoints for these compounds have been 

established, exposure and risks from free triazole and its conjugates will be addressed separately.

Enforcement Methods: An adequate gas chromatography method with nitrogen-phosphorusdetection (GC/NPD), Valent Method RM-41C-1-1, is available for enforcement of tolerances for 

residues of metconazole (cis- and trans- isomers) in plant commodities from the pea and bean, 

dried shelled, except soybean, subgroup 6C; the sunflower subgroup 20B, the rapeseed subgroup 

20A, the stone fruit crop group 12-12, and tree nut crop group 14-12. A confirmatory liquid 

chromatography/tandem mass spectrometry (LC/MS/MS) method, Method RM-41C-4, is 

available. For both methods, the reported limit of quantitation (LOQ) is 0.02 ppm for each 

isomer in each matrix.

 

An adequate GC/NPD method is available for enforcement of tolerances for residues of 

metconazole (cis- and trans-isomers) in livestock commodities. The enforcement method is a 

modified version of the German multiresidue method DFG S19. An acceptable confirmatory

procedure, gas chromatography/mass spectrometry (GC/MS), is included for the method. The 

LOQ is 0.01 ppm for each isomer in each matrix, for an LOQ of 0.02 ppm for total metconazole 

residues.

Multiresidue Methods: Multiresidue methods data have been submitted for metconazole. The 

multiresidue methods are not adequate for determining residues of metconazole for dietary

exposure assessment. The data (MRIDs 44721509 and 47790001) will be forwarded to the US 

FDA.

Storage Stability: Adequate storage stability data for cis- and trans-metconazole were previously

submitted to support the storage conditions and durations of samples of raw agricultural and 

processed commodities from the previously submitted crop field trials and processing studies on 

stone fruit, tree nuts, and canola. The currently submitted storage stability data for dry bean, dry

pea, and sunflower are adequate to support the intervals of frozen storage from harvest to 

analysis for dry bean, dry pea, and sunflower seed, meal, and oil. No corrections of residue 

values from the field trials or processing studies for loss of metconazole or triazole residues (TA 

in sunflowers and dry shelled beans/peas; 1,2,4-triazole, TA, and TAA in canola) are necessary.

Meat, Milk, Poultry, and Eggs: Based on the cattle feeding study and the calculated dietary

burden based on the maximum reasonably balanced diet (Table 1 Feedstuffs, June 2008), no 

changes are required in the established livestock tolerances as a result of the proposed/expanded 

uses. The established tolerances for meat byproducts of cattle, goat, horse, and sheep at 0.04 
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ppm and for egg at 0.04 ppm are adequate. No tolerances are established for milk; fat and meat

of cattle, goat, hog, horse, poultry, and sheep; or meat byproducts of hog and poultry since 

residues are not expected to occur in those commodities. If additional uses increase the dairy

cattle dietary burden, additional ruminant feeding studies conducted at higher rates may be 

needed.

Crop Field Trials: Adequate field trial data have been submitted for the pea and bean, dried 

shelled, except soybean, subgroup 6C and the sunflower subgroup 20B. Field trials were 

conducted on dry beans, dry peas, and sunflowers. The studies adequately reflect the proposed 

use patterns. The number of field trials and geographic representations are adequate. The 

residue data are supported by adequate storage stability data. The analytical methods (the 

GC/NPD method adapted from Valent Method RM-41C-1 for metconazole and the LC/MS/MS 

method adapted from Morse Laboratories Meth-160 for TA) are adequate for analysis of the 

residues of concern. Although triazole fungicides are typically monitored for residues of all 

three triazole metabolites (i.e., 1,2,4-triazole, TA, and TAA), HED previously concluded that 

only analysis for TA need be conducted in the subject studies (refer to HED’s Chemistry Science 

Advisory Council minutes, 8/11/2010 meeting).

The previously submitted field trial data on canola, cherry, peach, plum, almond, and pecan are 

adequate to support the rapeseed subgroup 20A, the stone fruit subgroup 12-12, and the tree nut 

group 14-12. The studies adequately reflect the proposed use patterns. The number of field 

trials and geographic representation are adequate. Adequate storage stability data are available 

to support the field trial data. An adequate data collection method, the GC/NPD method RM41C-1, was used to determine metconazole (cis- and trans- isomers) in canola, stone fruit, and 

tree nuts. Residues of 1,2,4-triazole, TA, and TAA were determined in canola seed using an 

adequate LC/MS/MS method (Morse Laboratories Method 160). Although stone fruit and tree 

nut samples were not analyzed for the triazole metabolites, field trial data for triazoles are not 

required for those petitions submitted in 2006.

Processing Studies: Adequate processing studies have been conducted on canola, plums, and 

sunflowers.

Canola: Metconazole (the sum of cis- and trans-isomers) was non-detectable in/on canola seed, 

meal and refined oil samples reflecting treatment at a 5x rate; therefore, separate tolerances are 

not required for canola meal and oil. Residues of 1,2,4-triazole were also not detectable in 

canola seed, meal and refined oil reflecting treatment at 5x. Residues of TA and TAA do not 

concentrate in oil. However, residues of TA and TAA concentrated in canola meal by 2.1x and 

1.4x, respectively.

Plum: Metconazole (the sum of cis- and trans-isomers) concentrates 2.3x in prunes.

Sunflower: Metconazole (the sum of cis- and trans-isomers) does not concentrate in sunflower 

meal and oil. Residues of TA concentrate 2.9x in sunflower meal, but do not concentrate in oil. 

Confined Accumulation in Rotational Crops: The nature of the residue in rotational crops is 

adequately understood. The metabolism of metconazole appears to proceed in rotational crops 
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via similar mechanisms as in primary crops and to be more extensive than that observed in 

primary crops (banana, canola, mandarin, pea, and wheat). The residue of concern for the 

tolerance expression in rotational crops is metconazole. The residue of concern for the risk 

assessment in rotational crops except small grains is metconazole; the residues of concern for the 

risk assessment in small grains as rotational crops is metconazole and the metabolite M11.

Since the confined study indicated the potential for quantifiable metconazole residues in rotated 

crop commodities, limited field rotational crop trials were conducted. 

Field Accumulation in Rotational Crops: Adequate limited field rotational crop studies have 

previously been submitted. Based on the limited field rotational crop trials, rotational crop 

restrictions are included on the registered Metconazole 50 WDG labels (EPA Reg. No. 59639-

147). The same rotational crop restrictions on the proposed Metconazole 50 WDG label (as 

shown in Section 3.3) are adequate.

International Tolerances: There are no Codex maximum residue limits (MRLs) established for 

metconazole.

Residue definitions are harmonized with Canada. Tolerances in the US are established for 

residues of metconazole, including its metabolites and degradates. In both the US and Canada, 

compliance with the tolerance/MRL levels is determined by measuring only metconazole.

 

The recommended tolerance levels are harmonized with Canada.

A human health risk assessment is forthcoming.

2.0 Regulatory Recommendations

Provided the Section B/label is revised as requested, there are no residue chemistry

considerations that would preclude granting the requested registration and establishing the 

recommended tolerances for metconazole on the pea and bean, dried shelled, except soybean, 

subgroup 6C and the sunflower subgroup 20B; expansion of the canola tolerance to the rapeseed 

subgroup 20A; and conversion of the established tolerances and registrations for the stone fruit 

crop group 12 and tree nut crop group 14 to the stone fruit crop group 12-12 and the tree nut crop 

group 14-12. The specific tolerance recommendations are discussed in Section 2.2, and label 

modifications are discussed in Section 2.3.
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2.1 Data Deficiencies/Data Needs

Data gaps to be addressed prior to a tolerance being established/registration allowed

Refer to Section 2.3 for label modifications.

Data that may be required for future uses

If additional uses increase the dairy cattle dietary burden, additional ruminant feeding studies 

conducted at higher rates may be needed.

2.2 Tolerance Considerations

2.2.1 Enforcement Analytical Method

An adequate GC/NPD method, Valent Method RM-41C-1-1, is available for enforcement of 

tolerances for residues of metconazole (cis- and trans- isomers) in plant commodities. A 

confirmatory LC/MS/MS method, Method RM-41C-4, is available. For both methods, the 

reported LOQ is 0.02 ppm for each isomer in each matrix. The method has been validated by the 

ACB/BEAD and was found adequate for enforcing tolerances for residues of metconazole per se

in plant commodities. No radiovalidation data were submitted for method RM-41C-1-1; 

however, HED has concluded that because the extraction solvent used for the proposed 

enforcement method is similar to the aqueous organic solvent mixtures used in the plant 

metabolism studies, radiovalidation of the method is not required.

An adequate GC/NPD method is available for enforcement of tolerances for residues of 

metconazole (cis- and trans-isomers) in livestock commodities. The enforcement method is a 

modified version of the German multiresidue method DFG S19. The LOQ is 0.01 ppm for each 

isomer in each matrix, for an LOQ of 0.02 ppm for total metconazole residues. An acceptable 

confirmatory procedure (GC/MS) is included for the method. The method has been validated by

ACB/BEAD and was found adequate for enforcing tolerances for residues of metconazole (cisand trans-isomers) in/on livestock commodities. No radiovalidation data were submitted; 

however, because DFG S19 is an established multiresidue method, these data are not required.

2.2.2 Recommended Tolerances

The petitioner’s proposed residue definition (tolerance expression) is adequate and is consistent 

with the S. Knizner memo dated 5/27/09. The petitioner requested the establishment of tolerances

for residues of metconazole, including its metabolites and degradates. Compliance with the

tolerance levels specified below is to be determined by measuring only metconazole [5-[(4-

chlorophenyl)methyl]-2,2-dimethyl-1-(1H-1,2,4-triazol-1-ylmethyl)cyclopentanol] as the sum of its

cis- and trans-isomers.
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Table 2.2.2. Tolerance Summary for Metconazole.

Commodity Established/Proposed 

Tolerance (ppm)

HEDRecommended 

Tolerance 

(ppm)

Comments 

(correct commodity 

definition)

Pea and bean, dried shelled,

except soybean, subgroup 6C

0.15 0.15 The 0.15 ppm level 

harmonizes with the 

Canadian MRL. Based on

calculations using the OECD

calculator for dry pea (0.08 

ppm) and <0.04 ppm residues 

for dry bean, a tolerance of

0.08 ppm would have been

recommended.

Sunflower subgroup 20B 0.9 0.7

Rapeseed subgroup 20A 0.04 0.08 The 0.08 ppm level 

harmonizes with the 

Canadian MRL.

Fruit, stone, group 12-12 0.2 0.2

Nut, tree, group 14-12 0.04 0.04

Canola seed 0.04 None Remove upon establishment 

of rapeseed subgroup 20A 

tolerance.

Fruit, stone, group 12 0.20 None Remove upon establishment 

of fruit, stone, group 12-12 

tolerance.

Nut, tree, group 14 0.04 None Remove upon establishment 

of nut, tree, group 14-12 

tolerance

Pistachio 0.04 None Remove upon establishment 

of nut, tree, group 14-12 

tolerance

2.2.3 Revisions to Petitioned-For Tolerances

The proposed tolerance on the sunflower subgroup 20B is 0.9 ppm; HED is recommending a 

decrease to 0.7 ppm based on the OECD tolerance calculation procedures with two studies 

combined as not independent.

The proposed tolerance for the rapeseed subgroup 20A is 0.04 ppm. HED is recommending an 

increase to 0.08 ppm to harmonize with the Canadian MRL. Based on calculations using the 

OECD calculator for canola, a tolerance of 0.04 ppm would have been recommended.

2.2.4 International Harmonization

There are no Codex maximum residue limits (MRLs) established for metconazole.

Residue definitions are harmonized with Canada. Tolerances in the US are established for 

residues of metconazole, including its metabolites and degradates. In both the US and Canada, 
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compliance with the tolerance/MRL levels is determined by measuring only metconazole.

 

The recommended tolerance levels are harmonized with Canada.

 

Refer to the International Residue Limits (IRL) table in Appendix C.

2.3 Label Recommendations

860.1200 Directions for Use

The Section B/label must be revised to include the following statement for the dried shelled pea 

and bean, except soybean, subgroup 6C: “Do not apply to cowpea or field pea used for livestock 

feed.”

The Section B/label should be revised to include the interval between applications for pecan and 

pistachio.

3.0 Introduction

Metconazole is a broad-spectrum triazole fungicide that works systemically by preventing spore 

formation and inhibiting mycelial growth. Metconazole acts primarily as an inhibitor of 

ergosterol biosynthesis, thereby interfering with synthesis of fungal cell membranes and 

providing systemic seed and seedling protection.
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3.1 Chemical Identity

Table 3.1. Metconazole Nomenclature.

Chemical Structure

 cis-isomer trans-isomer

Common name Metconazole

Company experimental name KNF-S-474m (Kureha); BAS 555 F (BASF); V-10116 (Valent)

IUPAC name (1RS,5RS;1RS,5SR)-5-(4-chlorobenzyl)-2,2-dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl)cyclopentanol

CAS name 5-[(4-chlorophenyl)methyl]-2,2-dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl)cyclopentanol

CAS # 125116-23-6 (cis- and trans-isomers)

115850-27-6 (cis-isomer)

115850-28-7 (trans-isomer)

End-use product/EP Metconazole 50 WDG Fungicide (EPA Reg. No. 59639-147), a water-dispersible 

granule formulation containing 50% active ingredient.

Quash 50 WDG (EPA Reg. No. 59639-147), also known as V-10116 50 WDG

3.2 Physical/Chemical Characteristics

Metconazole is a granule formulation with a low vapor pressure. It is more soluble in organic 

solvents than in water. The physicochemical properties are reported in Table 3.2 below.

N

N

N

H C3

H C3

HO

Cl

N

N

N

H C3

H3C

HO

Cl
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Table 3.2. Physicochemical Properties of the Technical Grade Metconazole

Parameter Value Reference*

(MRID)

Molecular weight (g/mole) 319.8 --

Melting point/range (°C) 100.0-108.4°C (using Electrothermal Digital Melting 

Point Apparatus) (AC900,768 technical grade)

44721505

pH 5.81 at 25oC (1% aqueous suspension) 46808402

Relative density (20°C)

Asked for Density (g/cm3)

1.14 (relative density to water at 4°C, using capillarystoppered, density-specific gravity bottle) (Lot No. 

AC 8879-140B)

44721505

Water solubility (mg/L at 

20oC)

Using shake-flask method:

18.7 ± 1.0 mg/L (cis-isomer, WL148271, KNF-S-474m)

13.6 ± 1.7 mg/L (trans-isomer, WL148271, KNF-S474m)

44721505

Solvent solubility (g/L at 

20oC)

Solvent Metconazole cis trans 44721505

acetone 363 251 117

methanol 403 294 117

dichloromethane 481 343 141

ethyl acetate 260 173 90.0

propanol 132 86.6 46.7

toluene 103 66.2 38.0

hexane 1.40 0.929 0.483

Vapor pressure at 20°C (Pa) Using gas-saturation method:

< 1.23x10-5Pa or 9.23 x 10-8 mm Hg (metconazole)

< 1.04x10-5Pa or 7.80 x 10-8 mm Hg (cis-isomer)

< 1.96x10-6Pa or 1.47 x 10-8 mm Hg (trans-isomer)

44721505

Dissociation constant (pKa) 11.38±0.03 and 1.06±0.03 (in water at 29.1°C using 

spectrophotometric method; Lot No. AC 8879-140B) 

44721505

Octanol/water partition 

coefficient, Log(KOW)

At 20 oC (using flask shaking method):

Kow (log Kow) = 7090±989 (3.85) (Lot No. AC 8879-

140B) (TGAI)

Kow (log Kow) = 7150±803 (3.85) (cis-isomer, CL 

354,801)

Kow (log Kow) = 6800±1700 (3.8) (trans-isomer, CL 

354,802)

44721505

* DP #256877, Shyam Mathur, Ph.D., 9/12/2000 and DP #329168, Shyam Mathur, Ph.D., 7/13/07.
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3.3 Pesticide Use Pattern/Directions for Use (860.1200)

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

Applic. Timing, 

Type, and 

Equip.

Formulation

[EPA Reg. 

No.]

Applic. 

Rate 

(lb ai/A)

Max. 

No. 

Applic. 

per 

Year

Max. 

Yearly

Applic. 

Rate

(lb ai/A)

PHI

(days) Use Directions and Limitations1

Dried Shelled Pea and Bean, Except Soybean, Subgroup 6C

[Dried cultivars of bean (Lupinus); bean (Phaseolus) (includes field bean, kidney bean, lima bean (dry), navy 

bean, pinto bean, tepary bean); bean (Vigna) (includes adzuki bean, blackeyed pea, catjang, cowpea, crowder pea, 

moth bean, mung bean, rice bean, southern pea, urd bean); broad bean (dry); chickpea; guar; lablab bean; lentil; 

pea (Pisum) (includes field pea); pigeon pea]

Postemergence; 

Broadcast foliar 

sprays;

Ground or 

aerial 

equipment; 

Chemigation

50% WDG

[59639-147]

0.08 -

0.125

2 0.25 21 Apply when conditions favor 

disease development and prior to 

infection. 

A second application may be 

made at a 7- to 10-day interval. 

Apply in sufficient water to 

obtain thorough coverage of the 

plant.

Apply with ground equipment in 

a minimum of 20 gallons per 

acre (GPA) or by air in a 

minimum of 5 GPA.

Two applications may be made 

sequentially. Use a non-group 3 

fungicide in alternation with 

Metconazole 50 WDG 

Fungicide. 

Rapeseed Subgroup 20A

(Borage; crambe; cuphea; exchium; flax seed; gold of pleasure; hare’s ear mustard; lesquerella; lunaria; 

meadowfoam; milkweed; mustard seed; oil radish; poppy seed; rapeseed (canola varieties only); sesame; sweet 

rocket; cultivars, varieties and/or hybrids of these)

Broadcast foliar 

spray during 

flowering;

ground or aerial 

equipment.

50% WDG

[59639-147]

0.0625-

0.125

1 0.125 35 Make application between 20% 

and 50% bloom. Apply in 

sufficient water to obtain 

thorough coverage of the plant. 

Apply with ground equipment in

10-20 GPA or by air in a 

minimum of 5 GPA.

Stone Fruit, Crop Group 12-12

(Black cherry; capulin; Chinese Jujube; Nanking cherry; sweet cherry; tart cherry; cultivars, varieties and/or 

hybrids of these)

Broadcast foliar 

spray; 

ground or 

aerial 

equipment

50% WDG

[59639-147]

0.078-

0.125

3 0.375 14 Timing: 

For brown rot/blossom blight, 

green fruit rot/jacket rot, or 

cherry leaf spot, begin 

applications at green tip. If 

conditions are favorable for 

disease development, make 

additional applications at full 

bloom and at petal fall. 

For fruit brown rot, make
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applications 14 to 21 days prior 

to harvest. 

For powdery mildew, follow the 

brown rot/blossom blight 

schedule; make additional 

applications on a 10-14 day 

interval until terminal growth 

ceases; application can be made 

after harvest.

Apply as a foliar spray in 

sufficient water to obtain 

thorough coverage of blossoms, 

foliage, and or fruit.

Apply with ground equipment in 

100-400 GPA or by air in a 

minimum of 20 GPA.

Do not make more than 2 

applications after petal fall. 

Stone Fruit, Crop Group 12-12

(Apricot; Japanese apricot; nectarine and peach)

Broadcast foliar 

sprays; 

ground or 

aerial 

equipment

50% WDG

[59639-147]

0.078-

0.125

3 0.375 14 Timing: 

For brown rot/blossom blight, 

green fruit rot/jacket rot, scab, or 

shot hole, begin applications at 

early pink bud stage before 

infection occurs. If conditions 

are favorable for disease 

development, make additional 

applications at full bloom and at 

petal fall.

For fruit brown rot, make 

applications 14-21 days prior to 

harvest. 

For powdery mildew, follow the 

brown rot/blossom blight 

schedule; make additional 

applications on a 10-14 day 

interval until terminal growth 

ceases. Begin applications prior 

to disease development and 

continue at a 7-10 day interval.

For rust, begin application when 

bud tissue is susceptible to 

disease development (i.e., pink, 

white, or red bud). If conditions 

are favorable for disease 

development, make a second 

application at full bloom or at 

petal fall.
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Apply as a foliar spray in 

sufficient water to obtain 

thorough coverage of blossoms, 

foliage, and or fruit.

Apply with ground equipment in 

100-400 GPA or by air in a 

minimum of 20 GPA.

Do not make more than 2 

applications after petal fall. 

Stone Fruit, Crop Group 12-12

(American plum; beach plum; Canada plum; cherry plum; Chickasaw plum; Damson plum; Japanese plum; 

Klamath plum; plum; plumcot; prune plum; sloe)

Broadcast foliar 

spray; 

ground or 

aerial 

equipment

50% WDG

[59639-147]

0.078-

0.125

3 0.375 14 Timing: 

For brown rot/blossom blight 

and rust, begin applications at 

green tip. If conditions are 

favorable for disease 

development, make additional 

applications at full bloom and at 

petal fall. 

For powdery mildew, follow the 

brown rot/blossom blight 

schedule; make additional 

applications on a 10-14 day 

interval until terminal growth 

ceases.

Apply as a foliar spray in 

sufficient water to obtain 

thorough coverage of blossoms, 

foliage, and or fruit.

Apply with ground equipment in 

100-400 GPA or by air in a 

minimum of 20 GPA.

Do not make more than 2 

applications after petal fall

Do not apply Metconazole 50 

WDG Fungicide to “Stanley” 

type plums.” 

Sunflower Subgroup 20B

(Calendula; castor oil plant; Chinese tallowtree; euphorbia; evening primrose; jojoba; niger seed; rose hip; 

safflower; stokes aster; sunflower; tallowwood; tea oil plant; vernonia; cultivars, varieties, and/or hybrids of 

these)

Postemergence; 

Broadcast foliar 

spray;

Ground or 

aerial 

50% WDG

[59639-147]

0.078 -

0.125

2 0.25 21 Apply when conditions favor 

disease development and prior to 

infection. 

A second application may be 

made on a 7- to 14-day interval. 
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equipment Apply as a foliar spray in 

sufficient water to obtain 

thorough coverage of leaves.

Apply by ground in a minimum 

of 20 GPA or by air in a 

minimum of 5 GPA.

Two applications may be made 

sequentially.

Use a non-group 3 fungicide in 

alternation with Metconazole 50 

WDG Fungicide. 

Tree Nuts, Crop Group 14-12, Except Filbert, Pecan, and Pistachio

(African nut-tree; almond; beechnut; black walnut; Brazil nut; Brazilian pine; bunya; bur oak; butternut; Cajou 

nut; candlenut; cashew; chestnut; chinquapin; coconut; coquito nut; dika nut; English walnut; ginkgo; Guiana 

chestnut; heartnut; hickory nut; Japanese horse-chestnut; macadamia nut; mongongo nut; monkey-pot; monkey 

puzzle nut; Okari nut; Pachira nut; peach palm nut; pequi; Pili nut; pine nut; Sapucaia nut; tropical almond; 

yellowhorn; cultivars, varieties and/or hybrids of these)

Broadcast foliar 

spray;

Ground or 

aerial 

equipment

50% WDG

[59639-147]

0.078-

0.11 

4 0.44 25 Begin applications prior to 

disease development and 

continue at a 7 to 14 day interval 

throughout the year.

Apply as a foliar spray in 

sufficient water to obtain 

thorough coverage of blossoms, 

foliage and/or fruit.

Apply in 100-400 GPA with 

ground equipment or in a 

minimum of 20 GPA by air.

Do not make more than 2 

applications after petal fall.

Filbert (Hazelnut)

Broadcast foliar 

spray;

Ground or 

aerial 

equipment

50% WDG

[59639-147]

0.11 4 0.44 25 Begin applications starting at 

bud swell to bud break and 

continue at 10 or 14-day 

intervals.

Apply as a foliar spray in 

sufficient water to obtain 

thorough coverage of all 

branches. 

Apply in 100-400 GPA with 

ground equipment or in a 

minimum of 20 GPA by air.

Do not make more than 2 

sequential applications before 

switching to a non-Group 3 

fungicide for resistance 

management.

Pecan

Broadcast foliar 50% WDG 0.078- 4 0.44 25 Begin applications when leaves 
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spray;

Ground or 

aerial 

equipment

[59639-147] 0.11 reach one-half mature size. 

Continue to make scab 

applications if scab model 

predicts need.

Apply as a foliar spray in 

sufficient water to obtain 

thorough coverage of blossoms, 

foliage and/or fruit.

Apply in 100-400 GPA with 

ground equipment or in a 

minimum of 20 GPA by air.

Do not make more than 2 

sequential applications before 

switching to a non-Group 3 

fungicide for resistance 

management.

Pistachio

Broadcast foliar 

spray;

Ground or 

aerial 

equipment

50% WDG

[59639-147]

0.125 4 0.500 25 Apply prior to onset of disease 

development and continue on a 2 

to 3 week interval.

Apply as a foliar spray in 

sufficient water to obtain 

thorough coverage of blossoms, 

foliage and/or fruit.

Apply in 100-400 GPA with 

ground equipment or in a 

minimum of 20 GPA by air.

Do not make more than 2 

sequential applications before 

switching to a non-Group 3 

fungicide for resistance 

management.

1 Rotational Crop Restrictions: 

Immediate plant-back is allowed for barley, corn, cotton, oat, peanut, rye, soybean, sugar beet, triticale, wheat, and 

those crops listed on the label.

A 30-day plant-back interval is required for Brassica Leafy Vegetables and Leafy Vegetables.

Do not plant any crop, except barley, corn, cotton, oat, peanut, rye, soybean, sugar beet, triticale, wheat, Brassica 

Leafy Vegetables, Leafy Vegetables and those crops listed on the label, earlier than 120 days after applying 

Metconazole 50 WDG Fungicide.

Conclusions. Metconazole 50 WDG Fungicide (EPA Reg. No. 59639-147) is to be applied to 

crops in the pea and bean, dried shelled, except soybean, subgroup 6C; the sunflower subgroup 

20B; the rapeseed subgroup 20A; the stone fruit crop group 12-12, and the tree nut crop group 

14-12. Applications are to be made as broadcast foliar sprays in sufficient water for thorough 

coverage using ground equipment (including chemigation) or aerial equipment. Depending on 

the crop and the targeted fungal disease, single application rates range from 0.0625-0.125 lb 

ai/A. Depending on the crop, a maximum of one to four applications can be made with 

minimum RTIs ranging from 7 to 14 days except for pecan (interval not specified) and pistachio 
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(2-3 week interval); the yearly application rates range from 0.125 to 0.500 lb ai/A. PHIs range 

from 14-35 days. Immediate plant-back is allowed for barley, corn, cotton, oat, peanut, rye, 

soybean, sugar beet, triticale, wheat, and those crops listed on the label. A 30-day plant-back 

interval (PBI) is required for Brassica leafy vegetables and leafy vegetables. A 120-day PBI 

applies to other crops.

Pending the following revisions, the Section B/label is adequate to allow evaluation of the 

residue data relative to the proposed use:

The Section B/label must be revised to include the following statement for the dried shelled pea 

and bean, except soybean, subgroup 6C: “Do not apply to cowpea or field pea used for livestock 

feed.”

The Section B/label should be revised to include the interval between applications for pecan.

4.0 Metabolite/Degradate Residue Profile

4.1 Nature of the Residue

4.1.1 Summary of Plant Metabolism (860.1300)

DP# 403859, S. Funk, 2/14/13

DP# 348168, N. Dodd, 2/20/08

DP# 348234, C. Olinger, 2/11/08 (Report of the Residues of Concern Knowledgebase Subcommittee; ROCKS 

memo)

DP# 324541, N. Dodd, 12/14/05

No new metabolism data were submitted with the subject petition. Metabolism studies with 

banana, canola, mandarin, pea, and wheat were previously submitted. The metabolism of 

metconazole was found to be similar in all crops investigated. The main metabolic route of 

metconazole in crops is via oxidative hydroxylation of the methylene groups, the methyl groups 

on the cyclopentyl ring, and possibly the cyclopentyl ring. In addition, monohydroxylation may

occur at the various pro-chiral carbons of metconazole, giving rise to chromatographically 

distinguishable stereoisomeric structures. The detection of TA and triazole conjugates in the 

canola, pea, and wheat studies indicates that the methylene group between the triazole and 

cyclopentyl rings is susceptible to oxidative hydroxylation. HED determined that metconazole 

(parent) is the residue of concern for both the tolerance expression and risk assessment purposes 

in plants except for cereal grains; the residues of concern for risk assessment in cereal grains are 

metconazole and the metabolite M11. 

Conclusions. The nature of the residue in crops in the pea and bean, dried shelled, except 

soybean, subgroup 6C; the sunflower subgroup 20B, the rapeseed subgroup 20A, the stone fruit 

crop group 12-12, and the tree nut crop group 14-12 is adequately understood based on 

metabolism studies on banana, canola, mandarin, pea, and wheat. The metabolism of 

metconazole was similar in all crops investigated. Metconazole (parent) is the residue of 

concern for the tolerance expression for primary and rotational crops. Metconazole is the residue 

of concern for risk assessment purposes in primary and rotational crops except for cereal grains; 
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the residues of concern for risk assessment in cereal grains (as both primary and rotational crops) 

are metconazole and the metabolite M11.

HED also has concern for residues of 1,2,4-triazole, TA, and TAA in plants as a result of the use 

of metconazole. However, because separate endpoints for these compounds have been 

established, exposure and risks from free triazole and its conjugates will be addressed separately.

4.1.2 Summary of Livestock Metabolism (860.1300)

DP# 403859, S. Funk, 2/14/13

DP# 348234, C. Olinger, 2/11/08 (ROCKS memo)

DP# 348168, N. Dodd, 2/20/08

No new metabolism data were submitted with the subject petition. Adequate ruminant and 

poultry metabolism studies are available. The data indicate that the metabolism of metconazole 

in ruminants and poultry is generally similar. The major routes of metabolism involve oxidation 

and/or oxidative hydroxylation of the methyl group at position 2 of the cyclopentyl ring and 

oxidative hydroxylation of the phenyl ring. Glucuronic acid conjugates were observed in the 

goat metabolism studies, and sulfate ester conjugates were observed in the hen metabolism 

study. In addition, in the hen metabolism study with triazole-labeled metconazole, C-N bond 

cleavage releasing 1,2,4-T was observed. Based on the available data, HED determined that the 

residue of concern for the tolerance expression in livestock commodities is metconazole (parent). 

The residues of concern in livestock for purposes of the risk assessment are metconazole and 

metabolites M1 (free and conjugated), M12, and M31 (free and conjugated). 

Conclusions. The nature of the residue in livestock (ruminants and poultry) is adequately 

understood. The residue of concern for the tolerance expression in livestock commodities is 

metconazole. The residues of concern in livestock for purposes of the risk assessment are 

metconazole and metabolites M1 (free and its glucuronic acid conjugate), M12, and M31 (free 

and its glucuronic acid conjugate).

HED also has concern for residues of 1,2,4-triazole, TA, and TAA in livestock as a result of the 

use of metconazole. However, because separate endpoints for these compounds have been 

established, exposure and risks from free triazole and its conjugates will be addressed separately.

4.1.3 Summary of Confined Rotational Crops (860.l850)

DP# 403859, S. Funk, 2/14/13

DP# 348168, N. Dodd, 2/20/08 

DP# 348234, C. Olinger, 2/11/08 (ROCKS memo)

The nature of the residue in rotational crops is adequately defined. The metabolism of 

metconazole appears to proceed in rotational crops via similar mechanisms as in primary crops 

and to be more extensive than that observed in primary crops (banana, canola, mandarin, pea, 

and wheat). Two metabolites were identified in rotational crops that were not identified in 

primary crops, the stereoisomers M12 and M13. HED noted that these metabolites reflect further 

oxidation of the methyl groups on the cyclopentyl ring of metconazole. HED determined that the 

residues of concern for rotational crops are the same as for primary crops. The residue of 

concern for the tolerance expression in rotational crops is metconazole. The residue of concern 

for the risk assessment in rotational crops except small grains is metconazole; the residues of 
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concern for the risk assessment in small grains as rotational crops is metconazole and the 

metabolite M11.

The confined study indicated the potential for quantifiable metconazole residues in rotated crop 

commodities at 30- and 120-day plant-back intervals based on total radioactive residue (TRR) 

levels. Metconazole was quantifiable (>0.01 ppm) at both PBIs in all rotational crop matrices 

except wheat grain. Therefore, limited field rotational crop trials were conducted.

Conclusions. The nature of the residue in rotational crops is adequately understood. The 

metabolism of metconazole appears to proceed in rotational crops via similar mechanisms as in 

primary crops and to be more extensive than that observed in primary crops (banana, canola, 

mandarin, pea, and wheat). The residue of concern for the tolerance expression in rotational 

crops is metconazole. The residue of concern for the risk assessment in rotational crops except 

small grains is metconazole; the residues of concern for the risk assessment in small grains as 

rotational crops is metconazole and the metabolite M11.

Since the confined study indicated the potential for quantifiable metconazole residues in rotated 

crop commodities, limited field rotational crop trials were conducted.

HED also has concern for residues of 1,2,4-triazole, TA, and TAA in rotational crops as a result 

of the use of metconazole. However, because separate endpoints for these compounds have been 

established, exposure and risks from free triazole and its conjugates will be addressed separately.

 

4.1.4 Summary of Metabolites and Degradates

Refer to Appendix A for the summary table of chemical names and structures of parent and 

metabolites. 

4.2 Comparison of Metabolic Pathways

DP#441926, Y. Donovan, 3/12/08

The metabolism of metconazole was found to be similar in all crops investigated. The main 

metabolic route of metconazole in crops is via oxidative hydroxylation of the methylene groups, 

the methyl groups on the cyclopentyl ring, and possibly of the cyclopentyl ring. In addition, 

monohydroxylation may occur at the various pro-chiral carbons of metconazole, giving rise to 

chromatographically distinguishable stereoisomeric structures. Further oxidation of the 

hydroxylated metabolites to form dihydroxylated or carboxylated derivatives was also observed 

in the mandarin study. Finally glucose conjugation of the mono- and/or dihydroxylated 

metabolites was observed in all crops, yielding glucosides as terminal residues. The detection of 

TA and triazole conjugates in the canola, pea, and wheat studies indicates that the methylene 

group between the triazole and cyclopentyl rings is susceptible to oxidative hydroxylation. 

The metabolism of metconazole appears to proceed in rotational crops via similar mechanisms as 

in primary crops and to be more extensive than that observed in primary crops (banana, canola, 

mandarin, pea, and wheat).
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The metabolism of metconazole in ruminants and poultry was generally similar. The major 

routes of metabolism involved oxidation and/or oxidative hydroxylation of the methyl group at 

position 2 of the cyclopentyl ring and oxidative hydroxylation of the phenyl ring. Glucuronic 

acid conjugates were observed in the goat metabolism studies, and sulfate ester conjugates were 

observed in the hen metabolism study. In addition, in the hen metabolism study with triazolelabeled metconazole, C-N bond cleavage releasing 1,2,4-T was observed. 

Based on the above descriptions, it is concluded that there are significant similarities in plant and 

livestock metabolism. Metconazole was metabolized primarily through oxidative hydroxylation 

of the benzylic methylene and the methyl groups on the cyclopentyl ring, followed by

conjugation with glucose. The triazole metabolites (1,2,4-triazole, TA, and TAA) are also 

residues of concern. 

4.3 Residues of Concern Summary and Rationale

DP# 348234, C. Olinger, 2/11/08 (ROCKS memo)

A summary of the metabolites and degradates to be included in the risk assessment and tolerance 

expression are presented below in Table 4.3, followed by the rationale. 

Table 4.3. Summary of Metabolites and Degradates to be included in the Risk 

Assessment and Tolerance Expression

Matrix Residues Included In Risk 

Assessment

Residues Included In 

Tolerance Expression

Plants Primary and Rotational 

Crops, except Cereal Grains

Metconazole Metconazole

Primary and Rotational 

Crops, Cereal Grains only

Metconazole and M11 Metconazole

Livestock

Ruminant Metconazole; M1 and its 

glucuronic acid conjugate; M12; 

M31 and its glucuronic acid 

conjugate

Metconazole

Poultry

Drinking Water Metconazole Not Applicable

Note: For all triazole-containing pesticides, the triazole-containing metabolites 1,2,4-T, TA, and TAA should also 

be included as residues of concern for risk assessment purposes only for plant and livestock commodities. Since 

these metabolites are common to the entire class of triazole-derivative fungicides and because of differential toxicity 

between the metabolites and the various parent compounds, risks associated with exposure to 1,2,4-T and to 

TA/TAA are addressed in separate risk assessment documents.

M1 = 5-[(4-chlorophenyl)methyl]-2-methoxyl-2-methyl-1-(1H-1,2,4-triazol-1-ylmethyl)-1-cyclopentanol; M11 = 5-

[(4-chlorophenyl)methoxyl]-2,2-dimethyl-1-(1H-1,2,4-triazol-1-ylmethyl)-1-cyclopentanol; M12 = 5-[(4-

chlorophenyl)methyl]-2-carboxyl-2-methyl-1-(1H-1,2,4-triazol-1-ylmethyl)-1-cyclopentanol; M31 = 

(1S*,3R*,5S*)-3-hydroxy-cis-metconazole; 1,2,4-T = 1H-1,2,4-triazole; TAA = 1H-1,2,4-triazol-1-yl acetic acid; 

TA = 2-amino-3-(1H-1,2,4-triazol-1-yl)propanoic acid. (See Appendix A.)

Rationale:
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Plants

Metconazole is the major residue in plant commodities based on the nature of the residue and 

magnitude of residue studies in numerous crops, and is, therefore, a residue of concern for both 

tolerance expression and risk assessment purposes. The registrant analyzed for residues of three 

metabolites, M11, M21, and M30, in cereal grain magnitude of residue studies. M11 was found 

at levels exceeding 1 ppm in oat and wheat straw at the proposed application rate, and at higher 

relative amounts than observed in the nature of the residue studies. Toxicity data are not 

available for M11, but it has a very similar chemical structure to the parent compound; therefore, 

without empirical data, it is assumed to have equal toxicity to the parent. M11 needs to be 

included as a residue of concern for risk assessment purposes in cereal grains only. M12 was a 

major residue in one of the rotational crop studies. For any future uses with higher application 

rates that result in the need for rotational crop tolerances, HED should consider inclusion of the 

M12 metabolite for risk assessment purposes.

Livestock

The major residues observed in the ruminant and poultry metabolism studies were metconazole, 

M1, M12, and the glucuronic acid conjugates of M1 and M31. Since the parent compound is the 

major residue in many of the livestock commodities, it is the only residue that needs to be 

included in the tolerance expression. M1 is very similar to the parent with an additional 

hydroxyl group in the cyclopentanol ring, and M12 has a carboxylic acid group in the same ring. 

The analytical method used in the feeding study is able to quantify the parent compound, M12, 

M1, and the glucuronic acid conjugate of M1. Due to the chemical structural similarity to the 

parent and assumed equivalent toxicity, they should be included in the risk assessment. The 

conjugated nature of the M31 metabolite mitigates the hazard concern to some extent; however, 

in the absence of toxicity data for the M31 metabolite, and the chemical structural similarity to 

the parent and assumed equivalent toxicity to the parent compound, HED recommends that M31 

be included in the risk assessment only.

Triazoles

Metconazole is a member of the triazole-containing class of pesticides. HED generally includes 

1,2,4-T, TA, and TAA as residues of concern for risk assessment purposes for most triazolecontaining pesticides. 1,2,4-T was a major residue found in some livestock commodities, and 

TA and TAA were significant residues in some plant metabolism studies. Since these 

metabolites are common to the entire class of triazole-derivative fungicides and because of 

differential toxicity between the metabolites and the various parent compounds, risks associated 

with exposure to 1,2,4-T and to TA/TAA are addressed in separate risk assessment documents.

Water

In addition to the parent compound, three degradates were observed at greater than 10% of the 

applied dose in laboratory fate studies: M30, hydroxymetconazole, and M13. Metconazole is 

generally slow to degrade in the environment, and the environmental fate data suggest that 

microbial-mediated degradation is likely the major degradation pathway for the proposed 

terrestrial agricultural uses. Although M30 was a major soil aerobic transformation product in
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laboratory studies (approximately 13% of the applied dose), it was a not a significant degradation 

product in field dissipation studies (approximately 5% of the applied dose). 

Hydroxymetconazole was a major photolysis product, but photolysis would not be a significant 

route of dissipation in the environment for the existing and proposed uses. In addition, the loss 

of the chlorine in hydroxymetconazole lessens the hazard concern for the degradate. M13 was 

observed in only one water soil system of the two tested and at a level barely over 10%, and is,

therefore, not considered to be a significant degradate. HED recommends only the parent 

compound be included in the drinking water exposure and risk assessments since exposure is not 

likely to be significantly different if the major degradates were included in the assessment.

5.0 Residue Profile

5.1 Residue Analytical Methods (860.1340)

5.1.1 Data Collection Methods

49297801.der (dry bean)

49297802.der (dry pea)

49297803.de1 (sunflower)

49297803.de2 (sunflower processed commodities)

Dry Shelled Beans, Dry Shelled Peas, and Sunflower Seeds

Dry beans, dry peas, sunflower seeds, and sunflower processed commodities (meal and oil) were 

analyzed for residues of metconazole, determined as cis- and trans-metconazole, using a 

GC/NPD method adapted from Valent Method RM-41C-1 (dated 11/13/03). For determination 

of cis- and trans-metconazole, samples were extracted with acetonitrile (ACN):water (70:30, 

v:v), filtered, and concentrated to remove the ACN. Residues were partitioned into hexane and 

then into ACN. The resulting ACN phases were combined with ethyl acetate, concentrated to 

dryness, and redissolved in methanol (MeOH):water (1:1, v:v), then subjected to solid phase 

extraction (SPE) through a C18 cartridge. Residues were eluted with MeOH:water (5:1, v:v). 

The eluate was evaporated to an aqueous remainder, combined with ethyl acetate, and 

evaporated to dryness. Residues were then redissolved in toluene for GC/NPD analysis. The 

validated LOQ is 0.02 ppm for each isomer.

Samples were analyzed for residues of the triazole metabolite triazole alanine (TA) using an 

LC/MS/MS method adapted from Morse Laboratories Meth-160 (dated 6/27/03). For 

determination of TA, samples were extracted with methanol:water (80:20, v:v). Following the 

addition of Celite, the extracts were vacuum filtered, rinsed, and brought to volume with 

methanol:water (80:20, v:v). The resulting extract was purified by elution through a Bond Elut 

Certify II SPE cartridge. The resulting eluate was reduced to dryness then subjected to two 

derivatizations: an esterification using hydrochloric acid (HCl)/butanol and an acylation using 

heptafluorobutyric anhydride (HFBA). The resulting extract was evaporated to dryness, and 

redissolved in ACN/water for analysis by LC/MS/MS. The LOQ (determined as the LLMV) 

was 0.02 ppm. The limits of detection (LODs) were not reported.

Acceptable method validation and concurrent recovery data were reported for dry bean, dry pea, 

sunflower, and sunflower processed commodities at fortification levels of 0.02 and 0.2 ppm, thus 
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validating the methods. The fortification levels were adequate to bracket expected residue 

levels. Although triazole fungicides are typically monitored for residues of all three triazole 

metabolites (i.e., 1,2,4-triazole, TA, and TAA), HED previously concluded that only analysis for 

TA need be conducted in the subject study (refer to HED’s Chemistry Science Advisory Council 

minutes, 8/11/2010 meeting).

Canola

Samples of canola seed, meal, and oil were analyzed for residues of cis- and trans-metconazole 

using an adequate GC/NPD method (RM-41C-1). The validated LOQ is 0.02 ppm for each 

metconazole isomer; the LOQ for total metconazole residues (cis- + trans-isomers) is 0.04 ppm. 

Residues of 1,2,4-triazole, TA, and TAA were determined in canola seed, meal, and oil using an 

adequate LC/MS/MS method (Morse Laboratories Method 160). The validated LOQ of the 

LC/MS/MS method in canola matrices was 0.01 ppm for triazole and TAA and 0.03 ppm for TA. 

Almond, Pecan, Cherry, Peach, and Plum

Samples were analyzed for residues of cis- and trans-metconazole using an adequate GC/NPD 

method (RM-41C-1). The validated LOQ is 0.02 ppm for each metconazole isomer; the LOQ 

for total metconazole residues (cis- + trans-isomers) is 0.04 ppm. 

Conclusions. An acceptable data collection method was used for determination of metconazole. 

The method used for determination of metconazole (as cis- and trans-metconazole) in dry beans, 

dry peas, sunflower seeds, sunflower processed commodities (meal and refined oil), canola seed, 

canola processed commodities (meal and refined oil), almond nutmeat and hulls, cherries, 

peaches, plums, and prunes is a GC/NPD method adapted from Valent Method RM-41C-1. The 

method has been adequately validated as a data collection method based on acceptable method 

validation and concurrent recovery data. The LOQ of the method is 0.02 ppm for each analyte 

(cis- and trans-metconazole) in each matrix.

An acceptable data collection method was used for determination of triazoles. Samples of dry

beans, dry peas, sunflower seeds, and sunflower processed commodities (meal and oil) were 

analyzed for residues of TA using an LC/MS/MS method adapted from Morse Laboratories 

Meth-160 (dated 6/27/03). Residues of 1,2,4-triazole, TA, and TAA were determined in canola 

seed using Method 160. The method has been adequately validated as a data collection method 

based on acceptable concurrent recovery data. The validated LOQ for dry beans, dry peas, and 

sunflower seeds, meal, and oil is 0.02 ppm. The validated LOQ of the LC/MS/MS method in 

canola matrices was 0.01 ppm for triazole and TAA and 0.03 ppm for TA. 

5.1.2 Multi-Residue Methods (860.1360)

DP# 361110, D. Soderberg, 2/26/10 (MRID 47790001)

DP# 324541, N. Dodd, 12/14/05 (MRID 44721509)

The Agency previously reviewed multiresidue methods data for metconazole. 

Based on its chemical structure, metconazole was not tested using FDA Multiresidue Method 

Protocols A, B, and G. Testing of metconazole through protocols A, B and G is unnecessary
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because metconazole is not naturally fluorescent, is neither an N-methyl carbamate nor a 

substituted urea, nor does it possess a phenol or carboxylic acid group.

An acceptable GC response (Protocol C) was obtained under Level I conditions using Module 

DG5, with a DB-1 (100% methyl siloxane) GC column.

Metconazole in peach (a non-fatty food) was tested through Protocol D using electron capture 

detection (ECD). Metconazole could not be seen in the extract when tested using ECD without a 

cleanup step. When tested through Fluorisil cleanup protocols C1 and C5, the residues appeared 

to be poorly recoverable through a Fluorisil column, but the recovery was largely obscured when 

residues were determined by ECD. Thus, protocol D cannot be used with ECD, but a more 

selective NPD was not tried, so results were equivocal for possibilities with that or other more 

selective detectors. 

Metconazole in peach was also tested through Protocol E without cleanup. Results again showed 

that a cleanup was needed when using an ECD. Because of the previous results using protocol 

D, no attempt was made to try the Protocol E extract through a Fluorisil cleanup. Because of 

these poor results, no attempt was made to test metconazole through Protocol F (for fatty foods). 

Conclusions. Multiresidue methods data have been submitted for metconazole. The 

multiresidue methods are not adequate for determining residues of metconazole for dietary

exposure assessment. The data (MRIDs 44721509 and 47790001) will be forwarded to the US 

FDA.

5.1.3 Tolerance Enforcement Methods

DP# 348168, N Dodd, 2/20/08

DP# 350367, N. Dodd, 9/18/08

DP# 389556, N. Dodd, 9/29/11

Plants

An adequate GC/NPD method, Valent Method RM-41C-1-1, is available for enforcement of 

tolerances for residues of metconazole parent isomers (cis- and trans- metconazole) in plant 

commodities from dry bean, dry pea, sunflower, canola, stone fruit and tree nuts. A 

confirmatory LC/MS/MS method, Method RM-41C-4, is available.

In Method RM-41C-1-1, homogenized samples are extracted with ACN:water (70:30, v:v) and 

filtered. The extract is concentrated to remove ACN and partitioned with hexane (2x). The 

resulting hexane phases are combined and partitioned with ACN (2x), and the ACN phases are 

combined with ethyl acetate, concentrated to dryness, and redissolved in MeOH:water (1:1, v:v). 

The reconstituted extract is applied to a C18 SPE cartridge, and residues are eluted with 

MeOH:water (5:1, v:v). The eluate is evaporated to aqueous, combined with ethyl acetate, 

evaporated to dryness, and then redissolved in toluene for GC/NPD analysis. The reported LOQ 

is 0.02 ppm for each isomer.

In the confirmatory method RM-41C-4, homogenized samples are extracted with ACN/water, 

filtered, and concentrated to aqueous as above, then partitioned with hexane:ethyl acetate (9:1, 
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v:v; 2x). The resulting hexane/ethyl acetate phase is partitioned with ACN (2x) and the 

combined ACN phases are concentrated, mixed with ethyl acetate, and evaporated to dryness. 

The residues are dissolved in MeOH:water (1:1, v:v) and subjected to C18 SPE cleanup as 

described above. The resulting eluate is diluted with aqueous formic acid for LC/MS/MS 

analysis. The LOQ, based on the submitted method validation data, is 0.02 ppm for metconazole 

(total of cis and trans-isomers).

Method RM-41C-1-1 has undergone an acceptable independent laboratory validation (ILV) with 

almond nutmeat fortified at 0.02-0.2 ppm. Adequate recoveries were obtained for almond 

nutmeat, ranging from 93.5 to 111% for cis-metconazole and from 88.6 to 112% for transmetconazole. 

No radiovalidation data were submitted for method RM-41C-1-1; however, HED has concluded 

that because the extraction solvent used for the proposed enforcement method is similar to the 

aqueous organic solvent mixtures used in the plant metabolism studies, radiovalidation of the 

method is not required.

Method RM-41C-1-1 was forwarded to ACB/BEAD for petition method review (DP #339994, 

N. Dodd, 5/29/07). ACB/BEAD (DP# 339995, Paul Golden, ACB Project #B07-19, 2/15/08) 

reviewed the method and found it adequate as an enforcement method for determination of 

residues of metconazole (cis- and trans-isomers). 

Livestock

An adequate method is available for enforcement of tolerances for residues of metconazole (cisand trans-isomers) in livestock commodities. The enforcement method is a modified version of 

the German multiresidue method DFG S19. The LOQ is 0.01 ppm for each isomer, for an LOQ 

of 0.02 ppm for total metconazole residues. The method has been validated by ACB/BEAD and 

was found adequate for enforcement.

For milk, bovine muscle, and egg, samples are homogenized with water:acetone (1:2, v:v), then 

combined with ethyl acetate:cyclohexane (1:1, v:v), and sodium chloride. An aliquot of the 

resulting organic phase is filtered through sodium sulfate and concentrated by evaporation, then 

reconstituted in ethyl acetate. Sodium sulfate:sodium chloride (1:1, w:w) and cyclohexane are 

added, and the salts are allowed to precipitate. For fat, samples are blended with ACN:acetone 

(9:1, v:v) and Calflo E and Celite as adsorbents, filtered, and combined with isooctane. The 

extract is concentrated and redissolved in ethyl acetate:cyclohexane (1:1, v:v) as above. For all 

matrices, the resulting ethyl acetate/cyclohexane fractions are subjected to sequential cleanup on 

a GPC column (residues eluted with ethyl acetate/cyclohexane) and a silica gel mini-column 

(residues eluted with acetone). The resulting eluate is concentrated by rotary evaporation and

reconstituted in ethyl acetate for GC/NPD or GC/MS (confirmatory procedure) analysis. The 

method LOQ is 0.01 ppm for each isomer.

Method DFG S19 with modified extraction has undergone an acceptable ILV with grape, pea, 

wheat grain, rapeseed, milk, bovine muscle, egg, and bovine fat fortified with each isomer at 
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0.01 and 0.10 ppm. Adequate recoveries, generally within the acceptable range of 70-120%, 

were obtained for all matrices at both fortification levels.

An acceptable confirmatory procedure (GC/MS) was included for the method. No 

radiovalidation data were submitted; however, because DFG S19 is an established multiresidue 

method, these data are not required.

The method based on the German multiresidue method DFG S19 was forwarded to ACB/BEAD 

for a petition method review (DP #339992, N. Dodd, 5/29/07). ACB/BEAD (Paul Golden, ACB 

Project #B07-18, 2/8/08) conducted a successful petition method review, indicating that the 

method is adequate for enforcing tolerances for residues of metconazole (cis- and trans-isomers) 

in/on livestock commodities. 

Conclusions. An GC/NPD method, Valent Method RM-41C-1-1, is available for enforcement of 

tolerances for residues of metconazole (cis- and trans- isomers) in plant commodities from the 

pea and bean, dried shelled, except soybean, subgroup 6C; the sunflower subgroup 20B, the 

rapeseed subgroup 20A, the stone fruit crop group 12-12, and tree nut crop group 14-12. A 

confirmatory LC/MS/MS method, Method RM-41C-4, is available. For both methods, the 

reported LOQ is 0.02 ppm for each isomer in each matrix. The method has been validated by 

ACB/BEAD and was found adequate for enforcing tolerances for residues of metconazole per se

in plant commodities. No radiovalidation data were submitted for method RM-41C-1-1; 

however, HED has concluded that because the extraction solvent used for the proposed 

enforcement method is similar to the aqueous organic solvent mixtures used in the plant 

metabolism studies, radiovalidation of the method is not required.

An adequate GC/NPD method is available for enforcement of tolerances for residues of 

metconazole (cis- and trans-isomers) in livestock commodities. An acceptable confirmatory

procedure, GC/MS, is included for the method. The enforcement method is a modified version 

of the German multiresidue method DFG S19. The LOQ is 0.01 ppm for each isomer in each 

matrix, for an LOQ of 0.02 ppm for total metconazole residues. The method has been validated 

by ACB/BEAD and was found adequate for enforcing tolerances for residues of metconazole 

(cis- and trans-isomers) in/on livestock commodities. No radiovalidation data were submitted; 

however, because DFG S19 is an established multiresidue method, these data are not required.

5.1.4 Submittal of Analytical Reference Standards (860.1650)

DP# 386784, A. Acierto, 7/27/11

An analytical reference standard for metconazole, with an expiration date of 9/1/2015, is 

available in the EPA National Pesticide Standards Repository (personal communication between 

T. Cole, ACB, and Versar, e-mail 1/25/11).
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5.2 Storage Stability (860.1380)

DP# 403859, S. Funk, 2/14/13

DP# 363016, D. Drew, 1/12/12 (47606601.der).

DP# 350367, N. Dodd, 9/18/08

DP# 348168, N. Dodd, 2/20/08.

49297801.der (dry bean)

49297802.der (dry pea)

49297803.de1 (sunflower)

49297803.de2 (sunflower processed commodities)

Rapeseed Subgroup 20A, Stone Fruit, and Tree Nuts 

The previously submitted storage stability data for cis- and trans-metconazole are adequate to 

support the storage conditions and durations of samples of raw agricultural and processed 

commodities from the previously submitted crop field trials and processing studies on stone fruit 

and tree nuts (DP# 348168, N. Dodd, 2/2/08) and canola (DP# 350367, N. Dodd, 9/18/08). 

Dry Bean, Dry Pea, and Sunflower

Storage stability data submitted for dry peas and sunflower meal and oil are reported in Table 

5.2.1 below.

Table 5.2.1. Stability of Metconazole in Frozen Dry Peas and Sunflower Meal and Oil.

Analyte Spike

Level

(ppm)

Storage 

interval1

(days)

Fresh 

Fortification 

Recoveries (%)

Recovered Residues 

(ppm)

Mean 

Recovered 

Residues

(ppm)

Mean 

Recovery 

(%)

Corrected % 

recovery2

Dry Peas

cis-metconazole 0.2 419 83 NR3 NR 88 106

trans-metconazole 0.2 419 92 NR NR 79 86

Sunflower Meal

cis-metconazole 0.2 306 72.5 0.1791, 0.1494, 0.1545 0.1610 80.5 111

trans-metconazole 0.2 306 70.5 0.1507, 0.1406, 0.1459 0.1457 72.8 103

Sunflower Oil

cis-metconazole 0.2 305 117 0.2347, 0.1972, 0.2233 0.2184 109 93.2

trans-metconazole 0.2 305 89.7 0.1951, 0.2060, 0.2437 0.2149 107 119

1

Interval from fortification to extraction.

2 Corrected for recovery of freshly fortified samples.

3 NR = not reported.

The storage durations and conditions of samples from the crop field trials and sunflower 

processing study are presented in Table 5.2.2. 

Dry bean samples were stored frozen from harvest to extraction for a maximum of 258 days (8.5 

months) prior to analysis for cis- and trans-metconazole and for a maximum of 192 days (6.3 

months) prior to analysis for TA (Table 5.2.2). Samples were analyzed within 1-5 days of 

extraction. The available freezer storage stability data indicate that residues of cis- and transmetconazole were stable when stored frozen at ≤-20 °C in/on dry pea for up to 419 days (13.8 

months), and residues of TA were stable when stored frozen in/on canola seed and wheat grain 

for up to 4 years. 
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Dry pea samples were stored frozen from harvest to extraction for a maximum of 376 days (12.4 

months) prior to analysis for cis- and trans-metconazole and for a maximum of 417 days (13.7 

months) prior to analysis for TA (Table 5.2.2). Samples were analyzed within 2-14 days of 

extraction. The available freezer storage stability data indicate that residues of cis- and transmetconazole were stable when stored frozen at ≤-20 °C in/on dry pea for up to 419 days (13.8 

months), and residues of TA were stable when stored frozen in/on canola seed and wheat grain 

for up to 4 years. 

Sunflower seed samples were stored frozen from harvest to extraction for a maximum of 423 

days (13.9 months) prior to analysis for cis- and trans-metconazole and for a maximum of 472

days (15.5 months) prior to analysis for TA (Table 5.2.2). Samples were analyzed with 1-18 

days of extraction. The available storage stability data indicate that residues of cis- and transmetconazole were stable under frozen storage conditions for up to 26 months in/on soybean seed. 

Residues of TA have been shown to be stable in/on canola seed and wheat grain under frozen 

conditions for up to 4 years.

In the sunflower processing study, samples were stored frozen from harvest/processing to 

extraction for 389-403 days (12.8-13.2 months) for sunflower seed (RAC) and 141-149 days 

(4.6-4.9 months) for meal and oil (Table 5.2.2). Samples were analyzed within 1-14 days of 

extraction. Processing took place within 290-293 days (9.5-9.6 months) of harvest. The 

available storage stability data indicate that residues of cis- and trans-metconazole were stable 

under frozen storage conditions for up to 26 months in/on soybean seed. To support the sample 

storage intervals for sunflower meal and oil, a concurrent storage stability study was conducted 

with the field trial study; the results are presented in Table 5.2.1. The data demonstrate that 

residues of metconazole, determined as cis- and trans-metconazole, were stable in/on samples of 

sunflower meal and oil stored frozen for up to 306 and 305 days; 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)]. Residues of TA have been shown to be stable in/on canola seed,

meal, and wheat grain under frozen conditions for up to 4 years and up to 8 months in canola oil.
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Table 5.2.2. Summary of Storage Conditions.

Matrix Analyte Storage 

Temperature 

(°C)

Actual Storage Duration1

(days/months)

Interval of Demonstrated Storage 

Stability

Bean, dry Metconazole ~-20 148-258 days

(4.9-8.5 months)

Residues are stable for up to 419 days 

(13.8 months) in dry pea.2

TA 88-192 days

(2.9-6.3 months)

Residues are stable for up to 4 years 

in/on canola seed and wheat grain.

3

Pea, dry Metconazole ~-20 312-376 days 

(10.3-12.4 months)

Residues are stable for up to 419 days 

(13.8 months) in dry pea.2

TA 350-417 days 

(11.5-13.7 months)

Residues are stable for up to 4 years 

in/on canola seed and wheat grain.

3

Sunflower 

seed

Metconazole ~-20 355-423 days 

(11.7-13.9 months)

Residues of cis- and trans-metconazole 

were stable under frozen storage 

conditions for up to 22 months in/on 

almond nutmeat.

4

TA ~-20 388-472 days 

(12.8-15.5 months)

Residues are stable for up to 4 years 

in/on canola seed and wheat grain.

3

Sunflower, 

seed (for 

processing)

Metconazole ~ -20 389 days 

(12.8 months)

Residues of cis- and transmetconazole were stable under frozen 

storage conditions for up to 22

months in/on almond nutmeat.

4

Sunflower,

meal

142 days 

(4.7 months)

306 days (10.1 months)5

Sunflower, 

oil

141 days

(4.6 months)

305 days (10.0 months)5

Sunflower, 

seed

TA ~ -20 403 days

(13.2 months)

Residues of TA are stable for up to 4 

years in/on canola seed, meal, and 

wheat grain.

3

Sunflower, 

meal

149 days

(4.9 months)

Sunflower, 

oil

148 days 

(4.9 months)

Residues of TA are stable for up to 8 

months in canola oil.3

1

Field trial studies: Interval from harvest to extraction. Dry bean samples were analyzed within 1-5 days of 

extraction. Dry pea samples were analyzed within 2-14 days of extraction. Sunflower seed samples were analyzed 

within 1-18 days of extraction. 

 Sunflower processing study: Interval from harvest/processing to extraction. In the processing study, samples were 

analyzed within 1-14 days of extraction. Processing took place within 290-293 days (9.5-9.6 months) of harvest.

2 Based on concurrent dry pea storage stability study (MRID 4929780).

3 DP# 363016, D. Drew, 1/12/12 (47606601.der).

4 DP# 348168, N. Dodd, 2/20/08.

5 Based on concurrent sunflower storage stability study (MRID 49297803).

Conclusions: The currently submitted storage stability data are adequate to support the intervals 

of frozen storage from harvest to analysis for dry bean, dry pea, and sunflower seed, meal, and 

oil. The previously submitted storage stability data for cis- and trans-metconazole are adequate 

to support the storage conditions and durations of samples of raw agricultural and processed 

commodities from the previously submitted crop field trials and processing studies on stone fruit, 

tree nuts, and canola. No corrections of residue values from the field trials or processing studies 

for loss of metconazole residues are necessary.
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5.3 Residue Data

5.3.1 Crop Field Trials (860.1500)

DP# 350367, N. Dodd, 9/18/08; 47287801.de1 (Rapeseed subgroup 20A: canola)

DP# 371571, A. Acierto, 8/20/10 (Rapeseed subgroup 20A: canola)

DP# 348168, N. Dodd, 2/20/08 (stone fruits: cherry, peach, and plum; and tree nuts: almond and pecan)

DP# 361110, D. Soderberg, 2/26/10 (stone fruits: cherry, peach, and plum; and tree nuts: almond and pecan)

49297801.der (dry bean)

49297802.der (dry pea)

49297803.de1 (sunflower)

Shelled Dry Bean, Shelled Dry Pea, and Sunflower

As shown in Table 5.3.1, field trials were conducted on dry beans, dry peas, and sunflowers. 

Refer to the geographic distribution tables in Appendix B.

As discussed in Section 5.1.1, samples from all field trials were analyzed for residues of 

metconazole, determined as cis- and trans-metconazole, using a GC/NPD method adapted from 

Valent Method RM-41C-1 (dated 11/13/03). Samples were analyzed for residues of the triazole 

metabolite TA using an LC/MS/MS method adapted from Morse Laboratories Meth-160 (dated 

6/27/03). The LOQ (determined as the lowest level of method validation, LLMV) was 0.02 ppm 

for each analyte. Acceptable method validation and concurrent recovery data (with recoveries 

generally within the acceptable range of 70-120%) were reported for dry bean, dry pea, and

sunflower samples at fortification levels of 0.02 and 0.2 ppm, thus validating the methods as 

adequate data collection methods. The fortification levels were adequate to bracket expected 

residue levels. Although triazole fungicides are typically monitored for residues of all three 

triazole metabolites (i.e., 1,2,4-triazole, TA, and TAA), HED previously concluded that only

analysis for TA need be conducted in the subject studies (refer to HED’s Chemistry Science 

Advisory Council minutes, 8/11/2010 meeting).

As discussed in Section 5.2, the available storage stability data are adequate to support the 

storage conditions and intervals of samples from the field trials. All samples were maintained 

frozen at the testing facility, during shipping to the laboratory, and were stored frozen until 

analysis. 

Dry Bean

IR-4 has submitted field trial data for metconazole on dry beans. Thirteen field trials were 

conducted in the United States during the 2010 growing season in the North American Free 

Trade Agreement (NAFTA) Growing Zones 1 (NY; 1 trial), 5 (MI, NE, OH and WI; 6 trials), 7 

(ND; 1 trial), 8 (KS; 1 trial), 9 (NM; 1 trial), 10 (CA; 1 trial) and 11 (ID and WA; 2 trials). 

Each trial consisted of one untreated plot and one treated plot. Each treated plot received two 

foliar broadcast applications of the 50% water dispersible granule (WG) formulation of 

metconazole (Quash 50 WDG) at 0.119-0.133 lb ai/A/application for a total seasonal rate of 

0.245-0.259 lb ai/A. Applications were made at RTIs of 6-8 days using ground equipment in 

spray volumes of 15-51 gal/A. A nonionic surfactant (NIS) was included in the spray mixtures 
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for all applications. Samples of dry bean were harvested at PHIs of 19-23 days. At seven trials, 

samples were allowed to dry in the field for 3-12 days between harvest and collection. No 

residue decline trials were conducted.

Individual sample (and per-trial average) total residues of metconazole (determined as the sum of 

cis- and trans-metconazole) were below the LOQ (<0.04 ppm) in/on all samples. Corresponding 

residues of TA were <0.02-0.348 ppm (<0.02-0.346 ppm). 

Dry Pea

IR-4 has submitted field trial data for metconazole on dry peas. Five field trials were conducted 

in the United States during the 2010 growing season in the NAFTA Growing Zones 5 (NE; 1 

trial), 7 (ND; 1 trial), 10 (AZ; 1 trial) and 11 (ID and WA; 2 trials). One pair of trials conducted 

in Velva, ND (Zone 7) are separated by <20 miles and have been assessed for independence; 

HED has concluded that these trials should be considered replicates. The above field trial 

distribution incorporates this conclusion.

Each trial consisted of one untreated plot and one treated plot. Each treated plot received two 

foliar broadcast applications of the 50% WG formulation of metconazole (Quash 50 WDG) at 

0.124-0.131 lb ai/A/application for a total seasonal rate of 0.250-0.258 lb ai/A. Applications 

were made at RTIs of 7-8 days using ground equipment in spray volumes of 15-31 gal/A. An 

NIS was included in the spray mixtures for all applications. Samples of dry pea were harvested 

at PHIs of 20-22 days. At two trials, samples were allowed to dry in the field for 2-8 days 

between harvest and collection. At one trial, additional samples were collected to assess residue 

decline at PHIs of 9, 14, and 28 days.

Individual sample (and per-trial average) total residues of metconazole (determined as the sum of 

cis- and trans-metconazole) were <0.04-<0.062 ppm (<0.04-<0.0562 ppm). Corresponding 

residues of TA were 0.155-3.16 ppm (0.187-2.38 ppm). In the residue decline trial, average total 

residues of metconazole (determined as the sum of cis- and trans-metconazole) were below the 

LOQ at the 9-day PHI, increased at the 14-day PHI (<0.0546 ppm), and then decreases to at or 

below the LOQ with increasing PHIs. Corresponding average residues of TA were constant 

(0.172-0.202 ppm) at all sampling intervals.

Sunflower

IR-4 has submitted field trial data for metconazole on sunflowers. Ten field trials were 

conducted in Canada and the United States during the 2010 growing season in the NAFTA 

Growing Zones 5 (ND and SD; 3 trials), 7 (ND and NE; 3 trials), 8 (NM; 1 trial) and 14 (SK; 3

trials). One pair of trials conducted in Velva, ND were treated with the same spray solution, and, 

therefore, have been assessed for independence; it was concluded that these trials should be 

considered replicates. The above field trial distribution incorporates this conclusion.

Each trial consisted of one untreated plot and one treated plot. Each treated plot received two 

foliar broadcast applications of the 50% WG formulation of metconazole (Quash 50 WDG) at 

0.121-0.130 lb ai/A/application for a total seasonal rate of 0.245-0.259 lb ai/A. Applications 
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were made at RTIs of 7-8 days using ground equipment in spray volumes of 10-35 gal/A. An

NIS was included in the spray mixtures for all applications. Samples of sunflower were 

harvested at PHIs of 20-21 days. At three trials, samples were allowed to dry in the field or were 

bagged and hung to dry for 6-17 days between harvest and collection. At one trial, additional 

samples were collected to assess residue decline at PHIs of 7, 14 and 27 days.

Individual sample (and per-trial average) total residues of metconazole (determined as the sum of 

cis- and trans-metconazole) were <0.04-0.968 ppm (<0.04-0.440 ppm). Corresponding residues 

of TA were <0.02-0.252 ppm (<0.02-0.148 ppm). In the residue decline trial, total residues of 

metconazole (determined as the sum of cis- and trans-metconazole) and corresponding residues 

of TA in seed were at or below the LOQ in/on all samples; therefore, residue decline could not 

be determined.

Table 5.3.1. Summary of Residues from Field Trials with Metconazole.

Crop 

Matrix

Analyte Total 

Application 

Rate

(lb ai/A)

PHI 

(days)

n

1 Residues (ppm)

Min.2 Max.2 LAFT3 HAFT3 Median3 Mean3SD3

BEAN, DRY (Proposed Use = 0.25 lb ai/acre total application rate, 21-day PHI)

Bean, dry Metconazole (sum of 

cis- and trans-isomers)

0.245-0.259 19-23 13 <0.04 <0.04 <0.04 <0.04 0.04 0.04 N/A

TA 0.245-0.259 19-23 13 <0.02 0.348 <0.02 0.346 0.021 0.048 0.090

PEA, DRY (Proposed Use = 0.25 lb ai/acre total application rate, 21-day PHI)

Pea, dry Metconazole (sum of 

cis- and trans-isomers)

0.250-0.258 20-22 5 <0.04 <0.0620 <0.04 <0.0562 0.040 0.043 0.007

Pea, dry TA 0.250-0.258 20-22 5 0.155 3.16 0.187 2.38 0.591 0.864 0.869

SUNFLOWER (Proposed Use = 0.25 lb ai/acre total application rate, 21-day PHI)

Sunflower 

seed

Metconazole (sum of 

cis- and trans-isomers)

0.245-0.259 20-21 10 <0.04 0.968 <0.04 0.440 0.067 0.127 0.131

Sunflower 

seed

TA 0.245-0.259 20-21 10 <0.02 0.252 <0.02 0.148 0.049 0.054 0.039

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

LOQ (0.04 ppm for total metconazole and 0.02 ppm for TA). N/A = Not applicable.

Rapeseed Subgroup 20A

Valent previously submitted field trial data for canola, the representative crop for the rapeseed 

subgroup 20A. The field trials are adequate in number and geographic representation. Samples 

of canola seed were analyzed for residues of cis- and trans-metconazole using an adequate 

GC/NPD method (RM-41C-1). The validated LOQ is 0.02 ppm for each metconazole isomer; 

the LOQ for total metconazole residues (cis- + trans-isomers) is 0.04 ppm. Residues of 1,2,4-

triazole, TA, and TAA were determined in canola seed using an adequate LC/MS/MS method 

(Morse Laboratories Method 160). The validated LOQ of the LC/MS/MS method in canola 

matrices was 0.01 ppm for triazole and TAA and 0.03 ppm for TA. Adequate storage stability 

data are available supporting the storage duration prior to analysis of metconazole (parent) and 

triazole metabolites (1,2,4-triazole, TA, and TAA) in canola seed. The field trial residues for 

metconazole and the triazoles are summarized below in Tables 5.3.2 and 5.3.3, respectively.
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Table 5.3.2. Summary of Residue Data from Crop Field Trials with Metconazole (WDG).

Crop matrix Total Applic. 

Rate (lb ai/A)

PHI 

(days)

Residue Levels (ppm) 1

n Min. Max. HAFT 2 Median Mean Std. Dev.

Canola (proposed use = 0.125 lb ai/A total application rate, 35-day PHI)

Canola seed

0.124-0.130 35-49 14 <0.04 <0.04 <0.04 0.04 0.04 NA

0.245-0.250 37-49 4 <0.04 <0.04 <0.04 0.04 0.04 NA

0.632 35 3 <0.04 <0.04 <0.04 0.04 0.04 NA

1 The LOQ is 0.02 ppm for each isomer, for a combined LOQ of 0.04 ppm. For calculation of the median, mean, and standard 

deviation, the LOQ was used for samples with residues <LOQ.

2 HAFT = Highest Average Field Trial.

Table 5.3.3. Summary of Residue Data for the Triazole Metabolites from Canola Field Trials with 

Metconazole (WDG).

Commodity Total 

Applic. Rate

(lb ai/A)

PHI 

(days) Analyte

Residue Levels (ppm) 1

n 2 Min. Max. HAFT 3 Median Mean Std. Dev.

Canola (proposed use = 0.125 lb ai/A total application rate, 35-day PHI)

Canola seed 0.124-0.130 35-49

1,2,4-T 6 <0.01 <0.01 <0.01 0.01 0.01 NA

TA 46 0.18 0.50 0.49 0.28 0.31 0.14

TAA 6 <0.01 <0.01 <0.01 0.01 0.01 NA

1 The LOQ is 0.01 ppm for each triazole analyte. For calculation of the median, mean, and standard deviation, the LOQ was 

used for samples with residues <LOQ. 

2

For triazole analysis, seed samples were pooled by growing region to yield 3 pooled samples that were each analyzed in 

duplicate. Seeds from Trial F were not included in the pool samples as they were not of commercial quality.

3 HAFT = highest average residues from pooled regional samples.

4 TA residues were found in all control samples at 0.22-0.27 ppm and averaged 0.24 ppm.

Stone Fruit Crop Group 12-12

Valent previously submitted field trials on cherries, peaches, and plums, which are the 

representative crops of the stone fruit crop group 12-12. The field trials are adequate in number 

and geographic representation. Samples of stone fruit were analyzed for residues of cis- and 

trans-metconazole using an adequate GC/NPD method (RM-41C-1). The validated LOQ is 0.02 

ppm for each metconazole isomer; the LOQ for total metconazole residues (cis- + trans-isomers) 

is 0.04 ppm. Adequate storage stability data are available supporting the storage duration prior 

to analysis of metconazole (parent) in stone fruit. The field trial residues are summarized in 

Table 5.3.4 below.

Table 5.3.4. Summary of Residue Data from Stone Fruit Crop Field Trials with Metconazole

Crop 

matrix

Total Applic. 

Rate

(lb ai/A)

PHI

(days)

Analyte Residue Levels (ppm)1

n Min. Max. HAFT2 Median Mean Std. 

Dev.

STONE FRUIT (proposed use = 0.375 lb ai/A total application rate, 14-day PHI)

1.81 lb/gal FlC formulation

Cherry 0.405-0.416

0.538

(1 trial)

13-14 cis-Metconazole 16 <0.02 0.134 0.119 0.041 0.048 0.032

trans-Metconazole 16 <0.02 0.028 0.025 0.020 0.021 0.002

Metconazole 16 <0.04 0.162 0.143 0.061 0.068 0.033
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Table 5.3.4. Summary of Residue Data from Stone Fruit Crop Field Trials with Metconazole

Crop 

matrix

Total Applic. 

Rate

(lb ai/A)

PHI

(days)

Analyte Residue Levels (ppm)1

n Min. Max. HAFT2 Median Mean Std. 

Dev.

Peach 0.403-0.417

0.545

(1 trial)

13-14 cis-Metconazole 18 <0.020 0.073 0.066 0.027 0.030 0.015

trans-Metconazole 18 <0.020 <0.020 0.020 <0.020 <0.020 0.00

Metconazole 18 <0.040 <0.093 0.086 0.047 0.050 0.015

Plum 0.405-0.412

0.538

(1 trial)

13-14 cis-Metconazole 12 <0.020 0.04 0.06 0.020 0.024 0.008

trans-Metconazole 12 <0.020 <0.020 <0.020 <0.020 <0.020 --

Metconazole 12 <0.040 <0.060 0.060 0.040 0.044 0.008

50% WDG formulation

Cherry 0.407-0.410 14 cis-Metconazole 4 0.027 0.056 0.052 0.039 0.040 0.014

trans-Metconazole 4 <0.02 <0.02 0.02 0.020 0.020 0.020

Metconazole 4 0.049 <0.076 0.076 0.068 0.065 0.011

Peach 0.418 14 cis-Metconazole 2 <0.02 0.020 0.02 0.02 0.02 --

trans-Metconazole 2 <0.02 <0.02 0.02 0.02 0.02 --

Metconazole 2 <0.04 <0.040 0.04 0.04 0.04 --

Plum 0.408 14 cis-Metconazole 2 <0.02 0.020 0.02 0.02 0.02 --

trans-Metconazole 2 <0.02 <0.02 0.02 0.02 0.02 --

Metconazole 2 <0.04 <0.040 0.04 0.04 0.04 --

1 Values for “Metconazole” and “Total Residues” are reported on a sample basis and are therefore not summations 

of tabulated data.

2

 HAFT = Highest average field trial result.

Tree Nut Group 14-12

D348168, N. Dodd, 2/20/08 (almonds and pecans)

Valent previously submitted field trials for metconazole on almonds and pecans, the 

representative commodities of the tree nut crop group 14-12. The field trials are adequate in 

number and geographic representation. Samples of stone fruit were analyzed for residues of cisand trans-metconazole using an adequate GC/NPD method (RM-41C-1). The validated LOQ is 

0.02 ppm for each metconazole isomer; the LOQ for total metconazole residues (cis- + transisomers) is 0.04 ppm. Adequate storage stability data are available supporting the storage 

duration prior to analysis of metconazole (parent) in stone fruit. The field trial residues are 

summarized in Table 5.3.5 below.
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Table 5.3.5. Summary of Residue Data from Tree Nut Crop Field Trials with Metconazole1

Crop 

matrix

Total 

Applic. Rate

(lb ai/A)

PHI

(days)

Analyte Residue Levels (ppm)

n Min. Max. HAFT2 Median Mean Std. 

Dev.

TREE NUTS (proposed use = 0.44 or 0.50 lb ai/A total application rate, 25-day PHI)

1.81 lb/gal FlC formulation

Almond, 

hulls

0.543-0.570 25 cis-Metconazole 10 0.42 3.04 2.49 0.65 1.05 0.84

trans-Metconazole 10 0.08 0.65 0.50 0.13 0.22 0.19

Metconazole 10 0.50 3.69 2.82 0.78 1.27 1.03

0.394-0.408 25 cis-Metconazole 4 0.30 0.62 0.62 0.48 0.47 0.17

trans-Metconazole 4 0.07 0.15 0.14 0.11 0.11 0.04

Metconazole 4 0.37 0.76 0.76 0.59 0.58 0.21

Almond, 

nutmeat

0.543-0.570 25 cis-Metconazole 10 <0.02 <0.02 <0.02 0.02 0.02 --

trans-Metconazole 10 <0.02 <0.02 <0.02 0.02 0.02 --

Metconazole 10 <0.04 <0.04 <0.04 0.04 0.04 --

0.394-0.408 25 cis-Metconazole 4 <0.02 <0.02 <0.02 0.02 0.02 --

trans-Metconazole 4 <0.02 <0.02 <0.02 0.02 0.02 --

Metconazole 4 <0.04 <0.04 <0.04 0.04 0.04 --

Pecan,

nutmeat

0.502-0.537 25-32 cis-Metconazole 4 <0.02 <0.02 <0.02 0.02 0.02 --

trans-Metconazole 4 <0.02 <0.02 <0.02 0.02 0.02 --

Metconazole 6 <0.04 <0.04 <0.04 0.04 0.04 --

50% WDG formulation

Almond, 

hulls

0.402-0.407 25 cis-Metconazole 4 <0.02 1.69 1.51 0.68 0.77 0.87

trans-Metconazole 4 <0.02 0.33 0.31 0.15 0.16 0.17

Metconazole 4 <0.04 2.02 1.82 0.83 0.93 1.04

Almond, 

nutmeat

0.402-0.407 25 cis-Metconazole 4 <0.02 <0.02 <0.02 0.02 0.02 --

trans-Metconazole 4 <0.02 <0.02 <0.02 0.02 0.02 --

Metconazole 4 <0.04 <0.04 <0.04 0.04 0.04 --

Pecan,

nutmeat

0.529 26 cis-Metconazole 2 <0.02 <0.02 <0.02 0.02 0.02 --

trans-Metconazole 2 <0.02 <0.02 <0.02 0.02 0.02 --

Metconazole 2 <0.04 <0.04 <0.04 0.04 0.04 --

1 Values for “Metconazole” and “Total Residues” are reported on a sample basis and are therefore not summations 

of tabulated data.

2

 HAFT = Highest average field trial result.

Conclusions. Adequate field trial data have been submitted for the pea and bean, dried shelled, 

except soybean, subgroup 6C and the sunflower subgroup 20B. Field trials were conducted on 

dry beans, dry peas, and sunflowers. The studies adequately reflect the proposed use patterns. 

The number of field trials and geographic representations are adequate. The residue data are 

supported by adequate storage stability data. The analytical methods (the GC/NPD method 

adapted from Valent Method RM-41C-1 for metconazole and the LC/MS/MS method adapted 

from Morse Laboratories Meth-160 for TA) are adequate for analysis of the residues of concern. 

In samples of dry bean harvested 19-23 days after two applications of the 50% WG formulation 

of metconazole at a seasonal rate of 0.245-0.259 lb ai/A, individual sample (and per-trial 
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average) residues of total metconazole (determined the sum of cis- and trans-metconazole) were 

below the LOQ (<0.04 ppm) in/on all samples. Corresponding residues of TA were <0.02-0.348

ppm (<0.02-0.346 ppm). 

In samples of dry pea harvested 20-22 days after two applications of the 50% WG formulation of 

metconazole at a seasonal rate of 0.250-0.258 lb ai/A, individual sample (and per-trial average) 

residues of total metconazole (determined as the sum of cis- and trans-metconazole) were <0.04-

<0.0620 ppm (<0.04-<0.0562 ppm). Corresponding residues of TA were 0.155-3.16 ppm

(0.187-2.38 ppm). In the residue decline trial, average total residues of metconazole (determined 

as the sum of cis- and trans-metconazole) were below the LOQ at the 9-day PHI, increased at the 

14-day PHI (<0.0546 ppm), and then decreased to at or below the LOQ with increasing PHIs. 

Corresponding average residues of TA were constant (0.172-0.202 ppm) at all sampling 

intervals.

In samples of sunflower seed harvested 20-21 days after two applications of the 50% WG 

formulation of metconazole at a seasonal rate of 0.245-0.259 lb ai/A, individual sample (and pertrial average) residues of total metconazole (determined as the sum of cis- and transmetconazole) were <0.04-0.968 ppm (<0.04-0.440 ppm). Corresponding residues of TA were 

<0.02-0.252 ppm (<0.02-0.148 ppm). In the residue decline trial, total residues of metconazole 

(determined as the sum of cis- and trans-metconazole) and corresponding residues of TA in seed 

were at or below the LOQ in/on all samples; therefore, residue decline could not be determined.

The previously submitted field trial data on canola, cherry, peach, plum, almond, and pecan are 

adequate to support the rapeseed subgroup 20A, the stone fruit subgroup 12-12, and the tree nut 

group 14-12. The number of field trials and geographic representations are adequate. Adequate 

storage stability data are available to support the field trial data. An adequate data collection 

method, the GC/NPD method RM-41C-1, was used to determine metconazole (cis- and transisomers) in canola, stone fruit, and tree nuts. Residues of 1,2,4-triazole, TA, and TAA were 

determined in canola seed using an adequate LC/MS/MS method (Morse Laboratories Method 

160). Although stone fruit and tree nut samples were not analyzed for the triazole metabolites, 

field trial data for triazoles are not required for those petitions submitted in 2006.

5.3.2 Field Rotational Crops (860.1900)

DP# 380990, 3/24/11, A. Acierto 

DP# 361110, 2/26/10, D. Soderberg

DP# 348168, 2/20/08, N. Dodd 

No new field rotational crop studies have been submitted. Limited field rotational crop studies 

were previously submitted for the rotational crops radish, spinach, wheat, and lettuce after 

seasonal application rates of approximately 0.50 lb ai/A to soybeans, tomatoes, or wheat. Based 

on that data, HED required that end-use labels include plant-back restrictions of 30 days for leafy

vegetables and Brassica leafy vegetables and 120 days for all remaining crops other than those 

with labeled uses.

Rotational crop restrictions on both the current label dated 8/12/13 and the proposed label 

(Metconazole 50 WDG Fungicide, EPA Reg. No. 59639-147) are shown below:
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● Immediate plant-back is allowed for barley, corn, cotton, oat, peanut, rye, soybean, sugar beet, 

triticale, wheat, and those crops listed on the label. [Note: Peanut is included on the Metconazole 

50 WDG label; barley, corn, cotton, oat, rye, soybean, sugar beet, triticale, and wheat are on the 

Caramba® Fungicide label (EPA Reg. No. 7969-246, dated 6/13/13)].

● A 30-day plant-back interval is required for Brassica Leafy Vegetables and Leafy Vegetables.

● Do not plant any crop, except barley, corn, cotton, oat, peanut, rye, soybean, sugar beet, 

triticale, wheat, Brassica Leafy Vegetables, Leafy Vegetables and those crops listed on the label, 

earlier than 120 days after applying Metconazole 50 WDG Fungicide.

Conclusions. Adequate limited field rotational crop studies have previously been submitted. 

The rotational crop restrictions on the proposed label (Metconazole 50 WDG Fungicide, EPA 

Reg. No. 59639-147) are adequate.

Note: To support the field rotational crop studies, additional storage stability data were 

requested for cis- and trans-metconazole reflecting storage for up to 18 months for wheat grain 

and straw, 19 months for lettuce and wheat hay, and 21 months for radish roots and tops and 

wheat forage (DP# 348168 (N. Dodd, 2/20/08).

This deficiency has been resolved. HED has accepted the available storage stability data, 

including data showing storage stability data for potato for 31.5 months (DP# 380990, A. 

Acierto, 3/24/11); almond nutmeat for 22 months and almond hulls for 26 months (DP# 348168, 

N. Dodd, 2/20/08); and radish root, wheat hay, and soybean seed for 26 months (DP# 361110, D. 

Soderberg, 2/26/10).

5.3.3 Processed Food and Feed (860.1520)

DP# 350367, N. Dodd, 9/18/08 (canola)

DP# 348168, N. Dodd, 2/20/08 (plum)

49297803.de2 (sunflower)

Canola

A processing study on canola was previously submitted. Metconazole (50% WDG) was applied 

to canola as a single broadcast foliar application during flowering at 0.632 lb ai/A (5x rate the 

proposed rate). Samples of canola seed, meal and oil were analyzed for residues of cis- and 

trans-metconazole using an adequate GC/NPD method (RM-41C-1). Residues of 1,2,4-triazole, 

TA, and TAA were determined using an adequate LC/MS/MS method (Morse Laboratories 

Method 160). Adequate storage stability data are available supporting the storage duration prior 

to analysis of metconazole (parent) and triazole metabolites (1,2,4-triazole, TA, and TAA) in 

canola seed, meal, and oil. The processing factors for metconazole and the triazole-related 

residues are discussed in Table 5.3.3.1 below.

Plum

A processing study on plum was previously submitted. Metconazole (1.81 lb ai/gal FlC 

formulation) was applied three times for a total application rate of 2.04 lb ai/A/season (5.4x the 

maximum proposed seasonal application rate for stone fruits). Residues of metconazole in/on 
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plum samples were quantitated using GC/NPD method RM-41C-1. The method was adequate 

for data collection based on acceptable method validation and concurrent method recoveries. 

Adequate storage stability data on cherries are available to support the storage conditions and 

durations of samples from the plum processing study. The processing factor for metconazole

was determined to be 2.3x as shown in Table 5.3.3.1 below.

Sunflower

IR-4 submitted a processing study for metconazole on sunflower seed. The processed 

commodities of sunflower seed are meal and refined oil.

In one trial conducted in ND during the 2010 growing season, a 50% WG formulation of 

metconazole (Quash 50 WDG) was applied as two foliar broadcast applications to sunflower at 

an exaggerated rate of 0.630-0.635 lb ai/A/application for a total seasonal rate of 1.265 lb ai/A 

(5.1x the proposed total application rate). Applications were made at a 7-day RTI using ground 

equipment in spray volumes of 12 gal/A. An NIS was added to the spray mixture for each of the 

applications. Samples of sunflower seed were harvested at a PHI of 21 days and processed into 

meal and oil by GLP Technologies (Navasota, TX) using simulated commercial procedures. 

Adequate descriptions were provided of the processing procedures, including material balance 

summaries.

As discussed in Section 5.2, the available storage stability data are adequate to support the 

storage conditions and intervals of samples from the processing study. All samples were frozen 

at the testing facility and remained frozen during shipping and storage prior to processing and 

analysis.

Samples were analyzed for residues of metconazole, determined as cis- and trans-metconazole, 

using a GC/NPD method adapted from Valent Method RM-41C-1 (dated 11/13/03). Samples 

were analyzed for residues of the triazole metabolite triazole alanine (TA) using an LC/MS/MS 

method adapted from Morse Laboratories Meth-160 (dated 6/27/03). The LOQ (determined as 

the lowest level of method validation, LLMV) was 0.02 ppm for each analyte. Acceptable 

method validation and concurrent recovery data were reported for sunflower samples at 

fortification levels of 0.02-0.2 ppm, thus validating the methods. The fortification levels were 

adequate to bracket expected residue levels. Although triazole fungicides are typically 

monitored for residues of all three triazole metabolites (i.e., 1,2,4-triazole, TA, and TAA), HED 

previously concluded that only analysis for TA need be conducted in the subject study (refer to 

HED’s Chemistry Science Advisory Council minutes, 8/11/2010 meeting).

Following two foliar broadcast applications of the 50% WG formulation at total application rates 

of 1.265 lb ai/A, quantifiable residues of total metconazole (determined as the sum of cis- and 

trans-metconazole) were observed in/on sunflower seed (RAC), but were below the combined 

LOQ (<0.04 ppm) in meal and oil. Corresponding residues of TA were 0.0200 ppm in/on 

sunflower seed, 0.0580 ppm in meal, and below the LOQ (<0.02 ppm) in oil.

A comparison of the residues in sunflower seed (RAC) with those in each processed sunflower 

fraction indicated that total residues of metconazole (determined as the sum of cis- and transmetconazole) do not concentrate (processing factors <1x) in meal and oil. Residues of TA 
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concentrate in sunflower meal (processing factor of 2.9x), but do not concentrate in oil. These 

processing factors are less than or close to the theoretical concentration factors. The theoretical 

concentration factors for sunflower are 4.5x for meal and 2.5x for oil (Table 3, OCSPP 

860.1520).

Residues found in samples and processing factors are given in Table 5.3.3.2 below.

Table 5.3.3.1. Summary of Processing Factors for Metconazole (cis-and trans-isomers) in Canola.

RAC Processed Commodity Processing Factors 1

Metconazole 1,2,4-triazole TA TAA

Canola seed Meal NC NC 2.07x 1.43x

Refined oil NC NC 0.005x 1.0x

Plum Prune 2.3x NA2 NA NA

1

 NC = Not calculated; residues were below the LOQ in the RAC and the processed commodity.

2 NA = Not analyzed since analysis is not required for data submitted in 2006.

Table 5.3.3.2. Residue Data from Sunflower Processing Study with cis- and trans-Metconazole and TA.

RAC/Processed 

Commodity

Total 

Rate

lb ai/A

PHI

(day)

Analyte Residues 

(ppm)

1

Processing 

Factor

Median 

Processing 

Factor

Sunflower, seed 1.265 21 cis-metconazole 0.170 -- --

trans-metconazole 0.0362 -- --

Total metconazole 0.206 -- --

TA 0.0200 -- --

Sunflower, meal cis-metconazole <0.02 <0.1x --

trans-metconazole <0.02 <0.6x --

Total metconazole <0.04 <0.2x --

TA 0.0580 2.9x --

Sunflower, oil cis-metconazole <0.02 <0.1x --

trans-metconazole <0.02 <0.6x --

Total metconazole <0.04 <0.2x --

TA ND <1.0x --

1 ND = Not detected (<LOD). For seed, meal, and oil, respectively, the LODs were 0.00601, 0.00615, and 0.01330 

ppm for cis-metconazole and 0.00864, 0.01533, and 0.00589 ppm for trans-metconazole, and the LOQ was 0.02 

ppm for each analyte, for a combined LOQ of 0.04 ppm. For TA, the LODs were 0.00356, 0.02229, and 0.01207 

ppm for seed, meal, and oil, respectively, and the LOQ was 0.02 ppm. Combined residues and per trial averages 

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

Conclusions. Adequate processing studies have been submitted on canola, plum, and sunflower.

(Refer to Section 6.0 for a discussion of recommended tolerances for processed commodities.)

Canola: Metconazole residues (cis- and trans-metconazole) were non-detectable in/on seed, 

meal and refined oil samples from a field trial treated at an exaggerated 5x rate. Residues of 

1,2,4-triazole were also not detectable in the RAC treated at 5x and processed commodities 

(meal and refined oil). The data indicate that residues of TA and TAA do not concentrate in oil. 

However, residues of TA and TAA concentrated in canola meal by 2.1x and 1.4x, respectively.
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Plum: The processing study on plums treated at a 5.4x rate indicate that metconazole residues 

(cis- and trans-metconazole) concentrate 2.3x in prunes. 

Sunflower: Following two foliar broadcast applications of the 50% WG formulation at total 

application rates of 1.265 lb ai/A (5.1x the proposed total application rate), quantifiable residues 

of metconazole (cis- and trans-metconazole) were observed in/on sunflower seed (RAC). 

Metconazole residues (cis- and trans-metconazole) were below the combined LOQ (<0.04 ppm) 

in sunflower meal and oil, indicating that metconazole residues do not concentrate (processing 

factors <1x) in meal and oil. Corresponding residues of TA were 0.0200 ppm in/on sunflower 

seed, 0.0580 ppm in meal, and below the LOQ (<0.02 ppm) in oil; these data indicate that 

residues of TA concentrate in sunflower meal (processing factor of 2.9x), but do not concentrate 

in oil. 

Adequate storage stability data are available to support sample storage durations and conditions

for these processing studies. The data collection methods (the GC/NPD method adapted from 

Valent Method RM-41C-1 for metconazole and the LC/MS/MS method adapted from Morse 

Laboratories Meth-160 for 1,2,4-triazole, TA, and TAA) are adequate for analysis of the residues 

of concern.

The observed processing factors in these processing studies are less than the theoretical 

concentration factors. The theoretical processing factor is 3.5x for prunes (OCSPP 860.1520, 

Table 1). The theoretical processing factors are 1.9x for canola meal, 3.0x for canola oil, 4.5x 

for sunflower meal, and 2.5x for sunflower oil (based on separation into components; OCSPP 

860.1520, Table 3). 

5.3.4 Meat, Milk, Poultry and Eggs (860.1480)

DP# 348168, N. Dodd, 2/20/08 (cattle feeding study)

DP# 350367, N. Dodd, 9/18/08 (poultry feeding study)

DP# 399057, N. Dodd, 7/19/12

Adequate cattle and poultry feeding studies were previously submitted and are summarized 

below. Maximum residues of metconazole (sum of cis- and trans-isomers) and 1,2,4-triazole are 

reported below in Tables 5.3.4.1 and 5.3.4.2, respectively.

Cattle

In the cattle feeding study (MRID 46901914), cattle were dosed orally with metconazole at 4.73, 

14.6, and 45.7 ppm (low, mid, and high dose) in the diet via capsules for 28 consecutive days. 

These dose levels are respectively equivalent to 2.0x, 6.1x, and 19x the dietary burden for beef 

cattle and 0.56x, 1.7x, and 5.4x the dietary burden for dairy cattle. Residues of cis- and transmetconazole were determined in milk using method RM-41M-1 (GC/NPD) and in tissues using 

method RM-41M-2 (LC/MS/MS). The validated LOQs for RM-41M-1 were 0.02 ppm for each 

analyte in milk and 0.04 ppm for each analyte in cream. The validated LOQ for RM-41M-2 was 

0.02 ppm for each analyte in tissues. Low- and mid-dose samples were not analyzed for cis- and 

trans-metconazole except for mid-dose liver, which had residues of <0.02 ppm for each isomer. 

In high-dose liver, residues of cis- and trans-metconazole were <0.02-0.021 ppm and <0.02 ppm, 

respectively; maximum total metconazole residues (sum of cis- and trans-isomers) were <0.041 
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ppm in liver. Residues of cis- and trans-metconazole were <LOQ in all samples of whole milk, 

skim milk, cream, fat, muscle, and kidney from the high-dose group. The triazole metabolites 

(1,2,4-triazole, TA, and TAA) were not determined in the cattle feeding study.

Poultry

In the poultry feeding study (MRID 47406901), laying hens were dosed orally with metconazole 

at 2.05, 6.24, and 20.3 ppm (low, mid, and high dose) in the diet via capsules for 28 consecutive 

days. The dose levels are respectively equivalent to 5.4x, 16x, and 53x the dietary burden for

poultry. Residues of cis- and trans-metconazole were separately determined in eggs and tissues 

using the LC/MS/MS method RM-41M-2. The validated LOQ for RM-41M-2 is 0.02 ppm for 

each analyte in eggs and tissues. Residues of cis- and trans-metconazole were <LOQ in eggs 

from the low- and mid-dose groups, but quantifiable metconazole residues were found in eggs 

from the high-dose group, with total residues of cis- and trans-metconazole in eggs ranging from 

<0.04-<0.085 ppm. Residues of cis- and trans-metconazole were <LOQ in all samples of 

muscle, fat, and liver from all three dose groups.

Residues of 1,2,4-triazole in egg and poultry tissue samples were determined using the 

LC/MS/MS method (Morse Laboratories Method 160, Revision 2). The validated LOQ is 0.01 

ppm for triazole in eggs and tissues. Triazole residues were <LOQ (<0.01 ppm) in selected egg 

samples from the 1x and 3x groups, with the exception of one sample from the 3x group on Day

28, which had triazole residues of 0.011 ppm. In the 10x dose group, triazole residues were

quantifiable in all analyzed egg samples. Triazole residues plateaued in eggs by Day 7 and were 

0.015-0.026 ppm between Days 7-28 and averaged 0.02 ppm. In poultry tissues, triazole 

residues were <LOQ in fat from the 10x dose group and in muscle and liver from the 1x dose 

groups; however, triazole residues were quantifiable in muscle and liver from the 3x and 10x 

dose groups and increased with dose level. For both muscle and liver, triazole residues averaged 

0.01 ppm for the 3x dose group and 0.029 ppm for the 10x dose group. TA and TAA were not 

determined in eggs and poultry tissues.

Table 5.3.4.1. Summary of Livestock Feeding Studies with Metconazole

Commodity Feeding Level, ppm Residue in Tissue, ppm1 Tissue-to-Feed Ratio2

Milk (whole and skim) 45.7 <0.04 (<LOQ) --

Cream 45.7 <0.08 (<LOQ) --

Muscle (cattle) 45.7 <0.04 --

Fat (cattle) 45.7 <0.04 --

Liver (cattle) 14.6 <0.04 --

45.7 <0.041 0.00090

Kidney (cattle) 45.7 <0.04 --

Eggs 2.05 <0.04 --

6.24 <0.04 --

20.3 <0.085 0.0042

Muscle (poultry) 2.05 <0.04 --

6.24 <0.04 -

20.3 <0.04 --

Fat (poultry) 2.05 <0.04 --

6.24 <0.04 --

20.3 <0.04 --
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Liver (poultry) 2.05 <0.04 --

6.24 <0.04 --

20.3 <0.04 --

1 Maximum residues of metconazole (sum of cis- and trans-isomers).are reported. The LOQ is 0.04 ppm (0.02 ppm 

for each isomer) in all commodities except cream. The LOQ in cream is 0.08 ppm. Tissue-to-feed ratios were not 

calculated for matrices with residues of <LOQ.

2 Tissue-to-feed ratios were not calculated for matrices with residues of <LOQ.

Table 5.3.4.2. Summary of 1,2,4-Triazole Residues from Poultry Feeding Studies with Metconazole

Commodity Feeding Level, ppm Residue in Tissue, ppm1 Tissue-to-Feed Ratio2

Eggs 2.05 <0.01 --

6.24 0.011 0.0018

20.3 0.026 0.0013

Muscle (poultry) 2.05 <0.01 --

6.24 0.011 0.0018

20.3 0.031 0.0015

Fat (poultry) 20.3 <0.01 --

Liver (poultry) 2.05 <0.01 --

6.24 0.011 0.0018

20.3 0.032 0.0016

1 Maximum residues of 1,2,4-triazole, expressed as 1,2,4-triazole, are reported. The LOQ is 0.01 ppm.

2 Tissue-to-feed ratios were not calculated for matrices with residues of <LOQ.

5.3.4.1 Dietary Burden

Livestock feed items associated with the proposed/expanded uses are sunflower meal, safflower 

meal, canola meal, flax meal, and almond hulls.

There are no livestock feed items associated with stone fruits or tree nuts other than almonds.

There are no livestock feed items associated with dried shelled peas and beans except for 

cowpeas (seed, forage, and hay) and field peas (seed, vines/silage, and hay) (Table 1 Feedstuffs, 

June 2008). To avoid the need for residue data on livestock feed items of cowpea and field pea, 

the label should be revised to include the following statement for the dried shelled pea and bean, 

except soybean, subgroup 6C: “Do not apply to cowpea or field pea used for livestock feed.”

The dietary burdens for metconazole residues are based on the maximum reasonably balanced 

diets (Table 1 Feedstuffs, June 2008). The dietary burdens for metconazole residues are

calculated to be 2.4 ppm for beef cattle, 8.5 ppm for dairy cattle, 0.38 ppm for poultry, and 0.14

ppm for swine.

Table 5.3.4.1. Calculation of Dietary Burdens of Metconazole Residues to Livestock.

Feedstuff Type1 % Dry 

Matter2 % Diet2

HAFT4or 

Median5,6,7 Residue Level 

(ppm)

Dietary 

Contribution 

(ppm)

3

Beef Cattle (R = 15%; CC = 80%; PC = 5%)

Wheat hay R 88 15 HAFT 12.6 2.15

Barley grain CC 88 50 Median 0.48 0.27
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Table 5.3.4.1. Calculation of Dietary Burdens of Metconazole Residues to Livestock.

Feedstuff Type1 % Dry 

Matter2 % Diet2

HAFT4or 

Median5,6,7 Residue Level 

(ppm)

Dietary 

Contribution 

(ppm)

3

Wheat, milled byproducts CC 88 30 Median x 

PF

0.063 0.021

Sunflower meal PC 92 5 Median 0.067 0.0036

TOTAL BURDEN -- -- 100 -- -- 2.4

Dairy Cattle (R = 45%; CC = 45%; PC = 10%)

Oat hay R 90 10 HAFT 11.24 1.25

Wheat hay R 88 20 HAFT 12.6 2.86

Corn, sweet, stover R 83 15 HAFT 22.7 4.10

Barley grain CC 88 45 Median 0.48 0.25

Sunflower meal PC 92 10 Median 0.067 0.0073

TOTAL BURDEN -- -- 100 -- -- 8.5

Swine (CC = 85%; PC = 15%)

Barley grain CC 88 20 Median 0.48 0.096

Wheat, milled byproducts CC 88 50 Median x 

PF

0.063 0.032

Corn, field, grain CC 88 15 Median 0.01 0.0015

Sunflower meal PC 92 15 Median 0.067 0.010

TOTAL BURDEN -- -- 100 -- -- 0.14

Poultry (CC = 75%; PC = 25%)

Barley grain CC 88 75 Median 0.48 0.36

Sunflower meal PC 92 25 Median 0.067 0.017

TOTAL BURDEN -- -- 100 -- -- 0.38

1

 R: Roughage; CC: Carbohydrate concentrate; PC: Protein concentrate.

2

 Table 1 Feedstuffs (June 2008). 

3

 Contribution = ([tolerance /% DM] X % diet) for beef and dairy cattle; contribution = ([tolerance] X % diet) for 

poultry and swine.

4 The HAFT (highest average field trial) was used for sweet corn stover, oat hay, and wheat hay.

5 The median was used for the blended commodities field corn grain and barley grain.

6 The median times the processing factor (PF) was used for wheat milled byproducts (PF = 2.1x based on shorts, 

which had the highest PF considering bran, middlings, shorts).

7 The median was used for sunflower meal (OECD’s “Guidance on Residues in Livestock,” 

ENV/JM/MONO(2013)8, 9/4/13).

5.3.4.2 Estimated Secondary Residues in Livestock 

The secondary residue levels of metconazole in livestock commodities in Table 5.3.4.2 below 

were estimated using tissue-to-feed ratios from Table 5.3.4 above and the calculated dietary

burden from Table 5.3.4.1 above.

Table 5.3.4.2. Estimation of Secondary Residues from Use of Metconazole (sum of cis- and trans-isomers).

Commodity Tissue-to-Feed Ratio Dietary Burden (ppm) Expected Residue

Liver (cattle) 0.00090 8.5 0.0076

Eggs 0.0042 0.38 0.0016
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Tolerances for metconazole are established in 40 CFR §180.617 at 0.04 ppm for meat byproducts 

of cattle, goat, horse, and sheep. No tolerances are established for milk, meat, or fat of cattle, 

goat, horse, and sheep. A tolerance of 0.04 ppm is established in egg; no other tolerances are 

established for poultry. No tolerances are established for swine. 

Conclusions. Based on the cattle feeding study and the calculated dietary burden based on the 

maximum reasonably balanced diet (Table 1 Feedstuffs, June 2008), no changes are required in 

the established livestock tolerances as a result of the proposed/expanded uses. The established 

tolerances for meat byproducts of cattle, goat, horse, and sheep at 0.04 ppm and for egg at 0.04 

ppm are adequate. No tolerances are established for milk; fat and meat of cattle, goat, hog, 

horse, poultry, and sheep; or meat byproducts of hog and poultry since residues are not expected 

to occur in those commodities. If additional uses increase the dairy cattle dietary burden, 

additional ruminant feeding studies conducted at higher rates may be needed.

5.3.5 Food Handling (860.1460)

There are no proposed uses that are relevant to this guideline topic.

5.3.6 Water, Fish, and Irrigated Crops (860.1400)

There are no proposed uses that are relevant to this guideline topic.

5.4 Food Residue Profile

Crop Field Trials: Adequate field trial data have been submitted on dry beans, dry peas, 

sunflowers, canola, almonds, pecans, cherries, peaches, and plums. The studies adequately 

reflect the proposed use patterns. The number of field trials and geographic representations are 

adequate. The residue data are supported by adequate storage stability data. The analytical 

methods (the GC/NPD method adapted from Valent Method RM-41C-1 for metconazole and the 

LC/MS/MS method adapted from Morse Laboratories Meth-160 for triazoles) are adequate for 

analysis of the residues of concern. 

The residue data on canola, almonds, pecans, cherries, peaches, and plums support the 

established tolerance levels.

Metconazole residues (the sum of cis- and trans-isomers) in dry beans were all below the LOQ

(<0.04 ppm). Metconazole residues in dry pea were generally <LOQ. Metconazole residues 

sunflower seeds were generally quantifiable but low. Residues of TA were quantifiable (>0.02 

ppm) in 54% of the dry bean samples. TA was generally quantifiable in dry pea and sunflower 

seeds.

In the dry pea residue decline trial, average total residues of metconazole were below the LOQ at 

the 9-day PHI, increased at the 14-day PHI (<0.0546 ppm), and then decreased to at or below the 

LOQ with increasing PHIs. Corresponding average residues of TA were constant (0.172-0.202 

ppm) at all sampling intervals.
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In the sunflower residue decline trial, residue decline could not be determined because all 

residues were ≤LOQ.

Processing Studies: Adequate processing studies have been conducted on canola, plums, and 

sunflowers. 

Canola: Metconazole (the sum of cis- and trans-isomers) was non-detectable in/on canola seed, 

meal and refined oil samples reflecting treatment at a 5x rate; therefore, separate tolerances are 

not required for canola meal and oil. Residues of 1,2,4-triazole were also not detectable in 

canola seed, meal and refined oil reflecting treatment at 5x. Residues of TA and TAA do not 

concentrate in oil. However, residues of TA and TAA concentrated in canola meal by 2.1x and 

1.4x, respectively.

Plum: Metconazole (the sum of cis- and trans-isomers) concentrates 2.3x in prunes.

Sunflower: Metconazole (the sum of cis- and trans-isomers) does not concentrate in sunflower 

meal and oil. Residues of TA concentrate 2.9x in sunflower meal, but do not concentrate in oil. 

Storage Stability: The storage stability data are adequate to support the intervals of frozen 

storage from harvest to analysis for dry bean, dry pea, sunflower (seed, meal, and refined oil), 

canola (seed, meal and refined oil), cherry, peach, plum, and prune. No corrections of residue 

values from the field trials or processing studies for loss of metconazole or TA residues are 

necessary.

Meat, Milk, Poultry, and Eggs: Based on the cattle feeding study and the calculated dietary 

burden based on the maximum reasonably balanced diet (Table 1 Feedstuffs, June 2008), no 

changes are required in the established livestock tolerances as a result of the proposed/expanded 

uses. No residues are expected to occur in milk, fat, and meat, and residues in liver are not 

expected to exceed the established tolerance of 0.04 ppm. 

Rotational Crops: Since the confined study indicated the potential for quantifiable metconazole 

residues in rotated crop commodities, limited field rotational crop trials were conducted. Based 

on the limited field rotational crop trials, rotational crop restrictions are included on the 

registered label (Metconazole 50 WDG Fungicide, EPA Reg. No. 59639-147). The same 

rotational crop restrictions on the proposed label are adequate.

6.0 Tolerance Derivation

The established tolerances for canola, the stone fruit crop group 12, and the tree nut crop group 

14 are adequate for the rapeseed subgroup 20A, the stone fruit crop group 12-12, and the tree nut 

crop group 14-12, respectively. However, to harmonize with Canada, HED is recommending a 

tolerance of 0.08 ppm for the rapeseed subgroup 20A.

As shown in Appendix D, the Office of Economic Cooperation and Development (OECD) 

tolerance calculation procedures were used for calculating a tolerance for metconazole in 

sunflower. The statistical goal of the tolerance calculation procedures is to produce a maximum 
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residue limit MRL) proposal in the region of the 95th percentile of the underlying residues 

distribution.

The OECD tolerance procedures were used for calculating a tolerance for dry pea. However, to 

harmonize with Canada, HED is recommending a tolerance of 0.15 ppm on the pea and bean, 

dried shelled, except soybean, subgroup 6C.

The OECD tolerance calculation procedures were not used for metconazole in dry beans since all 

residues of metconazole (MRID 49297801) were <LOQ (<0.04 ppm) in dry beans.

Separate tolerances are not required for canola meal and oil since metconazole residues were 

non-detectable in/on seed, meal and refined oil samples from a field trial treated at an 

exaggerated 5x rate. Residues of 1,2,4-triazole were also not detectable in canola seed treated at 

5x and processed commodities (meal and refined oil). The data indicate that residues of TA and 

TAA do not concentrate in oil. However, residues of TA and TAA concentrated in canola meal 

by 2.1x and 1.4x, respectively.

Residues of metconazole concentrate 2.3x in prunes. Based on the HAFT residues in plum (0.06 

ppm) and the processing factor (2.3x), expected residues in prune would be 0.14 ppm. This 

value is less than the established/recommended 0.20 ppm tolerance for the stone fruit group; 

therefore, a separate tolerance for prune is not required.

Residues of metconazole do not concentrate in sunflower meal and oil; therefore, separate 

tolerances are not needed for sunflower meal and oil. Residues of TA concentrate in sunflower 

meal (processing factor of 2.9x), but do not concentrate in oil. 

Dry Pea (MRID 49297802)

The dataset for metconazole on dry pea consisted of data from five field trials representing foliar 

broadcast applications at the rate of 0.250-0.258 lb ai/A/season with PHIs of 20-22 days. The 

field trial application rates are within 25% of the maximum label application rate. The average 

field trial residue values used to calculate the tolerance are provided in Appendix D. Residues of 

metconazole were quantifiable in only one of five field trials. Using the OECD tolerance 

calculation procedures, the tolerance for the residues of metconazole in dry bean would be 0.08 

ppm, which is the higher result of dry bean (0.04 ppm) and dry pea (0.08 ppm). However, to 

harmonize with Canada, HED is recommending a tolerance of 0.15 ppm for the pea and bean, 

dried shelled, except soybean, subgroup 6C. 

Sunflower (MRID 49297803)

The dataset used to determine a tolerance for metconazole on sunflower consisted of data from 

ten field trials representing foliar broadcast applications at the rate of 0.245-0.259 lb ai/A/season

with PHIs of 20-21 days. The field trial application rates are within 25% of the maximum label 

application rate. The average field trial residue values used to calculate the tolerance are 

provided in Appendix D. Residues of metconazole were quantifiable in eight of ten field trials. 
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Using the OECD tolerance calculation procedures, the recommended tolerance for the residues 

of metconazole in sunflower is 0.7 ppm.
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Appendix A. Tabular Summary of Metabolites 

Table A.1. Structures and Names of Metconazole and Metabolites

Common name/code

ID No.

Chemical name Chemical structure

Metconazole

(AC 900768)

(CL 900768)

5-[(4-chlorophenyl)methyl]-2,2-

dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl)cyclopentanol

Cis-isomer

Trans-isomer

M1

(CL 359451)

5-[(4-chlorophenyl)methyl]-2-

methoxyl-2-methyl-1-(1H-1,2,4-

triazol-1-ylmethyl)-1-cyclopentanol

M11

(CL 382390)

5-[(4-chlorophenyl)methoxyl]-2,2-

dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl)-1-cyclopentanol

M12

(CL 359138)

5-[(4-chlorophenyl)methyl]-2-carboxyl2-methyl-1-(1H-1,2,4-

triazol-1-ylmethyl)-1-cyclopentanol

M13 

(CL359139)

3-(4-chlorobenzyl)-2-hydroxy-1-

methyl-2-[1,2,4]triazol-1-ylmethylcyclopentanecarboxylic acid

N

N

N

H3C

H3C

HO

Cl

N

N

N

H3C

H C3

HO

Cl

N N

N

Cl

H

H

HO CH2

CH3

OH

N N

N

Cl

HO

H

HO CH2

CH3

CH3

N

N

N

H C3

HO

Cl

HOOC

HO

N

N

N

Cl

HO

O
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Table A.1. Structures and Names of Metconazole and Metabolites

Common name/code

ID No.

Chemical name Chemical structure

M21

(CL 382391)

5-[(4-chlorophenyl)methoxyl]-2,2-

dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl)-1-cyclopentanol

M30

(CL 382389)

5-[(4-chlorophenyl)keto]-2,2-dimethyl1-(1H-1,2,4-triazol-1-ylmethyl)-1-

cyclopentanol

M31

(CL 359139)

(1S*,3R*,5S*)-3-hydroxy-cismetconazole

1,2,4-Triazole

(1,2,4-T; free triazole)

1H-1,2,4-triazole NH

N N

Triazolylalanine

(Triazole alanine)

(TA)

(M35)

(CL 147267)

2-amino-3-(1H-1,2,4-triazol-1-

yl)propanoic acid

Triazolylacetic acid

(Triazole acetic acid)

(TAA)

1H-1,2,4-triazol-1-yl acetic acid

Hydroxymetconazole (1RS,5RS,1RS,5SR)-5-(4-

hydroxybenzyl)-2,2-dimethyl-1-(1H1,2,4-triazol-1-ylmethyl)cyclopentanol 

HO

N

N N

Cl H3C

H3C

O

N

N

N

H3C

HO

Cl

H3C

HO

N

N

N

NH2

COOH

N

N

N COOH

N N

N

OH

HO
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Appendix B. Field Trial Geographic Distribution

Table C.1. Dry Bean Trial Numbers and Geographical Locations.

Crop No. 

Trials

NAFTA Growing Zone Total

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

Bean, dried Sub. 1 -- -- -- 6 -- 1 1 1 1 2 -- 13

Req.11/0 -- -- -- 5/4 -- 2/1 1/1 1/1 1/1 1/1 -- 12/9

1 As per Table 5 of 860.1500 for bean, dried; the second number reflects a 25% reduction in the number of field trials allowed for 

the crop as a representative commodity in support of a crop group/subgroup tolerance or when application results in no 

quantifiable residues.

Table C.2. Dry Pea Trial Numbers and Geographical Locations.

Crop No. 

Trials

NAFTA Growing Zone Total

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

Pea, dried Sub. -- -- -- -- 1 -- 1

2

-- -- 1 2 -- 5

Req.1-- -- -- -- -- -- -- -- -- -- -- -- 5

1 As per Table 1 of OCSPP 860.1500 for peas (dried shelled); requested 5 trials, regions are not specified.

2 HED has concluded that two trials conducted in ND (Zone 7) are replicate trials for purposes of OCSPP 860.1500 data 

requirements.

Table C.3. Sunflower Trial Numbers and Geographical Locations.

Crop No. 

Trials

NAFTA Growing Zone Total

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Sunflower Sub. -- -- -- -- 3 -- 3

3

1 -- -- -- -- -- 3 10

Req.1-- -- -- -- 3/2 -- 4/3 1/1 -- -- -- -- -- -- 8/6

Req.2-- -- -- -- 2 -- 1 -- -- -- -- -- -- 2 5

1 As per Table 5 of 860.1500 for sunflower; the second number reflects a 25% reduction in the number of field trials allowed for 

the crop as a representative commodity in support of a crop group/subgroup tolerance or when application results in no 

quantifiable residues.

2 As per Table 1.2 of PMRA Directive DIR98-02 for sunflower.

3

 HED has concluded that two trials conducted in Velva, ND (Zone 7) are replicate trials for purposes of OCSPP 860.1500 data 

requirements.
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Appendix C. International Residue Limits Table

Metconazole (125619; 08/27/2014)

Summary of US and International Tolerances and Maximum Residue Limits 

Residue Definition:

US Canada Mexico2 Codex

40 CFR §180.617

Metconazole [5-[(4-chlorophenyl)methyl]-

2,2-dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl)cyclopentanol]

5-[(4-chlorophenyl)methyl]-2,2-

dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl) cyclopentanol

None

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

US Canada Mexico2 Codex

Fruit, stone, group 12-12 0.2

0.2 American plums, apricots, 

beach plums, black cherries, 

Canada plums, capulins, cherry 

plums, chicksaw plums, damson 

plums, fresh prune plums, Japanese 

apricots, Japanese plums, klamath 

plums, nanking cherries, 

nectarines, peaches, plumcots, 

plums, sloes, sweet cherries, tart 

cherries

Nut, tree, group 14-12 0.04

0.04 African tree nuts, almond 

nuts, beechnuts, black walnuts, 

Brazil nuts, Brazilian pine nuts, 

bunya nuts, bur oak nuts, 

butternuts, Cajou nuts, candlenuts, 

cashew nuts, chestnuts, chinquapin 

nuts, coconuts, coquito nuts, dika 

nuts, English walnuts, ginkgo nuts, 

Guiana chestnuts, hazelnuts 

(filbert), heartnuts, hickory nuts, 

Japanese horse-chestnuts, 

macadamia nuts, mongongo nuts, 

monkey-pot nuts, monkey puzzle 

nuts, Okari nuts, Pachira nuts, 

peach palm nuts, peanuts, pecan 

nuts, pequi nuts, Pili nuts, pine 

nuts, pistachio nuts, Sapucaia nuts, 

tropical almond nuts, yellow horn 

nuts

Pea and bean, dried shelled,

except soybean, subgroup 6C

0.15

0.15 Dry (adzuki beans, beans, 

blackeyed peas, 

broad beans, catjang seeds, 

chickpeas, cowpea seeds, field 

peas, guar seeds, kidney beans, 

lablab beans, lentils, lima beans, 

moth beans, mung beans, navy 

beans, pigeon peas, pink beans, 

pinto beans, rice beans, southern 

peas, tepary beans, urd beans, grain 

lupin

0.05 dry soybeans
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Summary of US and International Tolerances and Maximum Residue Limits 

Residue Definition:

US Canada Mexico2 Codex

40 CFR §180.617

Metconazole [5-[(4-chlorophenyl)methyl]-

2,2-dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl)cyclopentanol]

5-[(4-chlorophenyl)methyl]-2,2-

dimethyl-1-(1H-1,2,4-triazol-1-

ylmethyl) cyclopentanol

None

Rapeseed subgroup 20A 0.08

0.08 Seeds (borage, cuphea, 

echium, flax, gold of pleasure, 

hare's ear mustard, milkweed, 

mustard (oilseed type), oil radish, 

poppy, rapeseed (canola), sesame, 

sweet rocket 

Sunflower subgroup 20B 0.7

Completed: M. Negussie; 08/27/2014

1

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

not those proposed by the applicant.

2 Mexico adopts US tolerances and/or Codex MRLs for its export purposes.
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Appendix D. OECD MRL Calculation Procedure Inputs/Outputs

Sunflower Seeds (MRID 49297803) - Metconazole

0.245-0.259 lb ai/A; 20-21 day PHI

Residues (mg/kg) n

< 0.04 2

0.0402 1

0.043 1

0.045 1

0.0883 1

0.0957 1

0.196 1

0.237 1

0.44 1

Metconazole

Sunflower Seeds

USA, Canada

0.245-0.259 lb ai/A; 20-21 day PHI

Total number of data (n) 10

Percentage of censored data 20%

Number of non-censored data 8

Lowest residue 0.040

Highest residue 0.440

Median residue 0.067

Mean 0.127

Standard deviation (SD) 0.131

Correction factor for censoring (CF) 0.867

Proposed MRL estimate

- Highest residue 0.440

- Mean + 4 SD 0.649

- CF x 3 Mean 0.329

Unrounded MRL 0.649

Rounded MRL 0.7
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Sunflower (MRID 49297803) – TA

0.245-0.259 lb ai/A; 20-21 day PHI

Residues (mg/kg) n

< 0.02 1

0.0213 1

0.0243 1

0.0253 1

0.042 1

0.0562 1

0.0654 1

0.0663 1

0.073 1

0.148 1

TA

Sunflower Seeds

USA, Canada

0.245-0.259 lb ai/A; 20-21 day PHI

Total number of data (n) 10

Percentage of censored data 10%

Number of non-censored data 9

Lowest residue 0.020

Highest residue 0.148

Median residue 0.049

Mean 0.054

Standard deviation (SD) 0.039

Correction factor for censoring (CF) 0.933

Proposed MRL estimate

- Highest residue 0.148

- Mean + 4 SD 0.209

- CF x 3 Mean 0.152

Unrounded MRL 0.209

Rounded MRL 0.2
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Dry Bean (MRID 49297801) – TA

0.245-0.259 lb ai/A; 19-23 day PHI

Residues (mg/kg) n

< 0.02 6

0.0208 1

0.0218 1

0.0236 1

0.0242 1

0.0275 1

0.0369 1

0.346 1

TA

Dry bean

USA

0.245-0.259 lb ai/A; 19-23 day PHI

Total number of data (n) 13

Percentage of censored data 46%

Number of non-censored data 7

Lowest residue 0.020

Highest residue 0.346

Median residue 0.021

Mean 0.048

Standard deviation (SD) 0.090

Correction factor for censoring (CF) 0.692

Proposed MRL estimate

- Highest residue 0.346

- Mean + 4 SD 0.407

- CF x 3 Mean 0.099

Unrounded MRL 0.407

Rounded MRL 0.4
Metconazole Summary of Analytical Chemistry and Residue Data Barcode D419223

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Dry Pea (MRID 49297802) – Metconazole

0.250-0.258 lb ai/A; 20-22 day PHI

Residues (mg/kg) n

< 0.04 4

0.0562 1

Metconazole

Dry Pea

USA

0.250-0.258 lb ai/A; 20-22 day PHI

Total number of data (n) 5

Percentage of censored data 80%

Number of non-censored data 1

Lowest residue 0.040

Highest residue 0.056

Median residue 0.040

Mean 0.043

Standard deviation (SD) 0.007

Correction factor for censoring (CF) 0.467

Proposed MRL estimate

- Highest residue 0.056

- Mean + 4 SD 0.072

- CF x 3 Mean 0.061

Unrounded MRL 0.072

Rounded MRL 0.08

High uncertainty of MRL estimate.

[Small dataset and high level of censoring]
Metconazole Summary of Analytical Chemistry and Residue Data Barcode D419223

Page 59 of 59

Dry Pea (MRID 49297802) - TA

0.250-0.258 lb ai/A; 20-22 day PHI

Residues (mg/kg) n

0.187 1

0.459 1

0.591 1

0.701 1

2.38 1

TA

Dry Pea

USA

0.250-0.258 lb ai/A; 20-22 day PHI

Total number of data (n) 5

Percentage of censored data 0%

Number of non-censored data 5

Lowest residue 0.187

Highest residue 2.380

Median residue 0.591

Mean 0.864

Standard deviation (SD) 0.869

Correction factor for censoring (CF) 1.000

Proposed MRL estimate

- Highest residue 2.380

- Mean + 4 SD 4.340

- CF x 3 Mean 2.591

Unrounded MRL 4.340

Rounded MRL 5

High uncertainty of MRL estimate.

[Small dataset]