Methoxyfenozide Summary of Analytical Chemistry and Residue Data OP Barcode 0425285 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, DC 20460 

OFFICE OF CHEMICAL SAFETY AND 

POLLUTION PREVENTION 

MEMORANDUM 

DATE: 31March2015 

SUBJECT: Methoxyfenozide. Petition to Establish Permanent Tolerances, and Associated 

Section 3 Registration, for Residues Resulting from Use of the Insecticide on 

Chives: and to Convert Stone Fruit Group 12 (Except Fresh Prune Plums) to 

Stone Fruit Group 12-1 2 (Except Fresh Prune Plums), and Tree Nut Group 14 to 

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

PC Code: I 21027 

Decision Number: 493332 

Petition: 4E8298 

DP Barcode: D425285 

Registration Number: 62719-442 

Regulatory Action: Section 3 

Risk Assessment Type: NA Case Number: 7431 

TXR Number: NA CAS Number: 161050-58-4 

MRID Number: 4942020 I 40 CFR: § 180.544 

FROM: 

THRU: 

and 

TO: 

William T. Drew, Chemist ~..) Risk Assessment Branch II (RAB2) 

Health Effects Division (HED). 7509P 

RAB2

Dennis 

/H

M

E

cNei

D. 7509P 

lly, Chemist 

r/"'. 

Q_ ~ <:- M 

( . 

~ { 

Thur

RAB4

ston 

/HED. 

Morton

7509

, Chemist 

P. Chemi~~~ry /'.?' P11 / ~ Council (ChemSAC) 

Donald Wilbur, Chemist \t!-M~ 

RAB3/HED, 7509P, ChemSAC 

Barbara Madden and Andrew Ertman, RM Team 5 

Minor Use and Emergency Response Branch (MUERB) 

Registration Division (RD). 7505P 

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Methoxyfenozide Summary of A nalytical Chemistry and Residue Data DP Barcode D425285 

Table of Contents 

1.0 Executive Sumn1ary ............................................ ........ .... .... ... .... .... ... ....... ............................. 4 

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

2.1 Data Deficiencies/Data Needs ......... .... .... ... .... .... .... .... .... ... .... ....... .... ... .... ... ... .... ... .... ........ 6 

2.2 Tolerance Considerations .................................................................................................. 6 

2.2.1 Enforcement Analytical Method/Multiresidue Methods .......................................... 6 

2.2.2 Recommended Tolerances .............................. ........... .... .............. ............................. 7 

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

2.2.4 International Harmonization ..................................................................................... 8 

2.3 Label Recommendations .............. .................................................................................... 9 

2.4 Submittal of Analytical Reference Standards (860.1650) .. ....... .... ....... ... .... ........... ... ...... 9 

3.0 Chen1ical Identity .................. ....... ........ .... .... ........ .... .... ....... .... ... .... .... ....... ... ....... .... ... .... .... 10 

3 .1 Nomenclature .. ... .... ....... ....... ........ ......................................................................... ....... .. 10 

3.2 Physicochemical Characteristics ......................... .... .... ....... ........... ....... .......................... 10 

3.3 Pesticide Use Pattern/Directions for Use (860.1200) ........ ....... ..................................... 11 

4.0 Metabolite/ Degradate Residue Profile .... ........ .... .... .... ....... ........... ....... ....... .... ....... ... .... ... .. 11 

4.1 Nature of the Residue ... ........... .... ........ .... .... .... .... ........... .... ... .... ... .... .... ... ....... ... .... .... ... .. 11 

4.1.1 Summary of Plant and/or Livestock Metabolism (860.1 300) ... ... .... .... ... .... ... .... ..... 12 

4.1 .2 Summary of Confined Rotational Crops (860.1850) .............. ................................. 13 

4.1.3 Summary of Rat Metabolism ... .... .... ........ .... ....... .... ........... ....... ....... ... .... .... .... ... ... .. 13 

4.1.4 Summary of Environmental Degradation ... .... .... .... .... ... .... ....... .... ... .... ... .... ... .... .... . 14 

5.0 Residue Profile .. ... .... .... ... .... .... ................... .... ........ .......................................................... .. 15 

5.1 Residue Analytical Methods (860.1340) ........................................... ........................... 15 

5. 1.1 Data Collection Methods .... .... ................ ... .... ......................................................... 15 

5. 1.2 Multi-Residue Methods (860. 1360) ... .... .... .... ......................................................... 16 

5.1.3 Tolerance Enforcement Methods ....... ........ .... .... ....... .... ....... .... ... .... ... .... .... ... .... ... ... 16 

5.2 Storage Stability (860.1380) ............. .... .... .... .... .... ........ ... .... ....... .... ... ... .... .... ....... .... ... ... 17 

5.3 Residue Data ...... ....... .... .... .... .... .... .... .... .... .... .... ............................................................. 18 

5.3. 1 Crop Field Trials (860.1500) ............. .... .... .... .... ....... .... .... ....... .... ... .... ... .... ... .... ... ... 18 

5.3.2 Field Rotational Crops (860.1900) .... .... .... .... .... .... .............. ........... ... ........... .......... 18 

5.3.3 Processed Food and Feed (860.1520) .... ........ ....... .... .... .............. .......... ........ ....... ... 19 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode 0425285 

5.3.4 Meat, Milk, Poultry and Eggs (860.1480) .............................................................. 19 

5.3.5. Food Handling (860.1460) ...................................................................................... 19 

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

5.4 Food Residue Profile ...................................................................................................... 19 

6.0 Tolerance Derivation .............. ........... ... ........... .............. .................... ... ... .......................... 20 

References ..................................................................................................................................... 20 

Attachment 1: International Residue Limit Status .. .... ....... ... ....... ............................................ .... 22 

Attachment 2: OECD Tolerance Assessment Calculations ......................................................... 24 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

1.0 Executive Summary 

Methoxyfenozide (with CAS name 3-methoxy-2-methylbenzoic acid 2-(3,5-dimethylbenzoyl]-2-

[ I, 1-dimethylethyl]hydrazide) is a diacylhydrazine insecticide used on a wide variety of food and 

feed crops for the control of lepidopterous pest species. Permanent tolerances are established for 

residues of methoxyfenozide in or on a wide variety of plant commodities, at levels ranging from 

0.02 ppm in peanuts and tuberous/corm vegetables (subgroup ID), to 400 ppm in herb subgroup 

l 9A (40CFR § l 80.544[a][ l ]). Permanent tolerances are also established for residues of 

methoxyfenozide in the milk, meat and fat of livestock (40CFR §180.544[a][J]), and for the 

combined residues of the parent and its glucuronide conjugate (RH-141 ,518) in eggs and meat 

byproducts at 0.02-0.40 ppm (40CFR § 180.544[a][2]). Additionally, permanent tolerances for 

methoxyfenozide are established in high-moisture rotational crops ( 40CFR § 180.544[ d][ 1 ]), and 

for the combined residues of the parent and its metabolites RH-1 5 1,055, RH-152,072 and RH117,236 in low-moisture rotational crops (40CFR § 180.544[d][2]). 

Interregional Research Project #4 (IR-4) has submitted a petition (PP#4E8298) proposing the use 

of methoxyfenozide as Intrepid 2F (EPA Registration # 62719-442) via foliar application on 

chives. The end-use product (EP), Intrepid 2F, is a flowable concentrate (FIC) formulation 

containing 2 pounds of active ingredient per gallon (lb ai/gal). 

IR-4 submitted a petition requesting the establishment of a permanent tolerance for residues of 

methoxyfenozide in or on fresh chive leaves. This proposed tolerance of 30.0 ppm in fresh 

chives is supported adequately by magnitude-of-residue data. Although only data for fresh and 

dried chives were submitted, several revised tolerances were proposed. Fresh chives are 

currently covered in green onion subgroup 3-078 at a tolerance of 5.0 ppm. IR-4 proposed the 

exclusion of fresh chives from subgroup 3-078, and establishment of a separate tolerance at 30.0 

ppm. Herb subgroup l 9A is currently established at 400 ppm with an exception for dried chives. 

IR-4 is proposing that the herb subgroup 19A tolerance is sufficient to cover dried chives, and 

that the exception for chives be removed and replaced with an exception for fresh chives. IR-4 is 

also proposing the conversion of tree nut group 14 to tree nut group 14-12, and conversion of 

stone fruit group 12 except fresh prune plum to stone fruit group 12-1 2 except fresh prune plum. 

Pending submission of a revised Section F (to propose tolerances and correct commodity 

definitions as recommended by HED), there are no residue chemistry issues that would preclude 

establishing the recommended tolerances. The specific residue chemistry findings are 

summarized below. 

Crop Field Trials: Chive field trials were conducted in the USA during the 2012 growing 

season. Three trials were conducted in North American Free Trade Agreement (NAFTA) Zones 

2 (MD; I trial) and 10 (CA; 2 trials). Follov.'1ng four foliar applications of the 2 lb ai/gal FIC 

formulation of methoxyfenozide at a total seasonal use rate of approximately 1.0 lb ai per acre 

(lb ai/ A), re-treatment intervals (RTls) of 8-11 days, and a pre-harvest interval (PHI) of 1 day, 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

maximum residues were 13 and 118 ppm in fresh and dried chive leaves, respectively. A residue 

decline study was not conducted. 

Processing Study: The processed commodity for fresh chives is dried chives, although these are 

considered a raw agricultural commodity (RAC) under herbs and spices group 19. Samples of 

dried chives were produced at the field trial sites, and subsequently analyzed along with the fresh 

chive samples. 

Residue Analytical Methods and Storage Stability: An acceptable method was used for residue 

quantitation, and adequate data are available to support sample storage durations and conditions. 

Validated methods are available for the enforcement of methoxyfenozide tolerances. An 

adequate method was used for the quantitation of methoxyfenozide residues in samples from the 

chive field trials, based on acceptable method validation and concurrent recovery data. 

Meat, Milk, Poultry and Eggs: The current action for the proposed use on chives (and updates 

of crop group 12 to group 12-12, and group 14 to group 14-12) do not require revisions to the 

existing tolerances in livestock commodities. 

MRL Harmonization: Codex has not established maximum residue limits (MRLs) for 

methoxyfenozide in either green onions or herbs. Canada's Pest Management Regulatory 

Agency (PMRA) has an existing MRL in various green onions/leeks at 5 mg/kg, which is 

harmonized with the existing tolerance of 5.0 ppm in green onion subgroup 3-07B. PMRA has 

an existing MRL in various fresh herbs at 80 mg/kg, which is not harmonized with the 

recommended tolerance of 400 ppm in herb subgroup l 9A, nor the recommended tolerance of 30 

ppm in chjve. 

Codex has an existing MRL in stone fruit at 2 mg/kg, which is not harmonized with the 

recommended tolerance of3.0 ppm in stone fruit group 12-12 except fresh prune plum. PMRA 

has existing MRLs in various plums/apricots/jujubes/sloes at 0.7 mg/kg, and in various 

cherries/peaches/nectarines at 6 mg/kg, neither of which is harrnoruzed with the recommended 

tolerance of3.0 ppm in stone fruit group 12-12 except fresh prune plum. 

Codex has an existing MRL in tree nuts at 0.1 mg/kg, which is harmonized with the 

recommended tolerance of 0. 10 ppm in tree nut group 14-12. PMRA has an existing MRL in a 

large variety of tree nuts at 0.1 mg/kg, which is harmonized with the recommended tolerance of 

0.10 ppm in tree nut group 14-12. 

2.0 Regulatory Recommendations 

HED has examined the residue chemistry database for methoxyfenozide. Pending submission of 

a revised Section F (to propose tolerances and commodity definitions as recommended by HED), 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

there are no residue chemistry issues that would preclude establishing the recommended 

tolerances. The recommended tolerances are listed in Table 2.2.2, below. 

Notes to RD: Upon establishment of the recommended tolerance in herb subgroup 19A, the 

existing tolerance in herb subgroup 19A except chive should be removed (40CFR 

§ l 80.544[a][ 1 ]). 

Upon establishment of the recommended tolerance in chive fresh leaves at 30 ppm (40CFR 

§ l 80.544[a][ I]), the existing tolerance for indirect or inadvertent methoxyfenozide residues in 

rotational crop chives at 4.5 ppm should be removed ( 40CFR § l 80.544[ d][2]). 

Upon establishment of the recommended tolerance in green onion subgroup 3-078 except chive 

fresh leaves, the existing tolerance in green onion subgroup 3-078 should be removed (40CFR 

§ l 80.544[a)[ I]). 

Upon establishment of the proposed tolerance in tree nut group 14-12, the existing tolerances in 

tree nut group 14 and pistachio should be removed (40CFR § l 80.544[a)[l]). 

Upon establishment of the proposed tolerance in stone fruit group 12-12 except fresh prune 

plum, the existing tolerance in stone fruit group 12 except fresh prune plum should be removed 

(40CFR § l 80.544[a](l]). 

2.1 Data Deficiencies/Data Needs 

None. 

2.2 Tolerance Considerations 

2.2.1 Enforcement Analytical Method/Multiresidue Methods 

Adequate methods using high performance liquid chromatography with ultraviolet or mass 

spectrometric detection (HPLC/UV or /MS) are available for enforcing the current tolerances for 

methoxyfenozide in primary and rotational crops, and in animal commodities. Depending on the 

plant commodity, the limits of quantitation (LOQs) for methoxyfenozide in primary crop 

commodities are 0.01-0.05 ppm. 

Data concerning the recovery of methoxyfenozide using the FDA multi residue method protocols 

(PAM Volume /) were previously submitted to, and reviewed by, HED. Methoxyfenozide was 

not recoverable by any of these procedures. The data were forwarded to FDA for evaluation, and 

the updating of PAM Volume I. 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

2.2.2 Recommended Tolerances 

TABLE2.2.2 Tolerance Summa ry for Methox fenozide ( 40CFR l 180.544). 

Proposed or Existing* Proposed or Existing* Recommended Correct Commodity Definition; 

Commodity Tolerance (oom) Tolerance (oom) Comments 

40CFR 180.5441 llll 

Fruit, stone, group 12-12, 3.0 3.0 Conversion from stone fruit group 12 

except plum, prune, fresh except fresh prune plum. 

Nut, tree, group 14-12 0.10 0.10 Conversion from tree nut group 14. 

Herb subgroup l 9A, 400 400 Herb subgroup 19A; based on fie ld trial 

except chive, fresh, leaves data on dried chives submitted by IR-4. 

Subgroup I 9A only includes dried 

chives, not fresh. 

Onion, green, subgroup 3- 5.0 5.0 Onion, green, subgroup 3-07 B, except 

078, except chive chive, fresh leaves; Based on field trial 

data on fresh chives submitted by IR-4. 

Chive, fresh, leaves 30.0 30 Chive, fresh leaves; based on field trial 

data on fresh chives submitted by IR-4. 

Herb subgroup l 9A. 400* Remove Replace with the tolerance in herb 

except chive* subgroup l 9A. 

Onion, green, subgroup 3- 5.0* Remove Replace with the tolerance in green 

078* onion subgroup 3-078 except chive. 

Fruit, stone, group 12, 3.0* Remove Conversion to stone fruit group 12-1 2 

except plum, prune, except fresh prune plum. 

fresh* 

Nut, tree, group 14* 0.1 0* Remove Conversion to tree nut group 14-12. 

40CFR 180. 44 dll2 1 

Chive* 4.5* Remove Covered by new chive tolerance in 

§ 180.544[a][ I]. 

* A tolerance is currently established at the listed level in the corresponding commodity. 

The currently established tolerance expression for methoxyfenozide is adequate, and includes 

both coverage and compliance statements for enforcement purposes. 

The use patterns, application rates, and representative commodities are the same for tree nut 

group 14 and tree nut group 14-12. Therefore, HED recommends in favor of allowing the 

conversion. 

The use patterns, application rates, and representative commodities are the same for stone fruit 

group 12 except fresh prune plum and stone fruit group 12-12 except fresh prune plum. 

Therefore, HED recommends in favor of allowing the conversion. 

2.2.3 Revisions to Petitioned-For Tolerances 

HED recommends in favor ofIR-4's proposal to remove the chive exception to the existing herb 

subgroup 19A except chive tolerance, but against IR-4 's proposal to replace it with an exception 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

for fresh chive leaves, which are not included in subgroup 19A (fresh chives are included in 

green onion subgroup 3-07B). The chive field trial data support a tolerance of 30 ppm in/on 

fresh chives, and 300 ppm inion dried chives, based on input of the residue data into the 

Organization for Economic Development and Cooperation (OECD) tolerance calculation 

procedure. However, dried chives will be covered under herb subgroup 19 A, which has an 

existing tolerance established at 400 ppm. 

Instead of the proposed tolerance in chive fresh leaves (30.0 ppm), HED recommends 

establishing the tolerance at 30 ppm. The Agency establishes tolerances using whole numbers 

for tolerances of 10 ppm or more, per the OECD's User Guide ENV/JM/MON0(2011)2 for the 

OECD tolerance calculation procedure. 

2.2.4 International Harmonization 

Codex has not established MRLs for methoxyfenozide in either green onions or herbs. Canada's 

PMRA has an existing MRL in various green onions/leeks at 5 mg/kg, which is harmonized with 

the existing tolerance of 5.0 ppm in green onion subgroup 3-078. PMRA has an existing MRL 

in various fresh herbs at 80 mg/kg, which is not harmonized with the recommended tolerance of 

400 ppm in herb subgroup 19A, nor the recommended tolerance of 30 ppm in chive. HED 

cannot recommend for harmonization of the subgroup l 9A tolerance with PMRA's MRL, 

because 400 ppm was the result of the Organization for Economic Cooperation and Development 

(OECD) tolerance calculation procedure for methoxyfenozide residues in basil, and reduction of 

the tolerance would result in the risk of violative residues resulting from proper use according to 

label directions. HED also cannot recommend for harmonization of the chive tolerance with 

PMRA's MRL, because increasing the recommended tolerance to 80 ppm in chive would result 

in the risk of undetected misuse (via seasonal application rates exceeding the label directions). 

Codex has an existing MRL in stone fruit at 2 mg/kg, which is not harmonized with the 

recommended tolerance of 3.0 ppm in stone fruit group 12-12 except fresh prune plum. HED 

cannot recommend for harmonization of the group 12-12 tolerance with Codex's MRL, because 

3.0 ppm was the result of the OECD tolerance calculation procedure for methoxyfenozide 

residues in stone fruit, and reduction of the tolerance would result in the risk of violative residues 

resulting from proper use according to label directions. PMRA has existing MRLs in various 

plums/apricots/jujubes/sloes at 0.7 mg/kg, and in various cherries/peaches/nectarines at 6 mg/kg, 

neither of which is harmonized with the recommended tolerance of 3.0 ppm in stone fruit group 

12-12 except fresh prune plum. HED cannot recommend for harmonization of the group 12-12 

tolerance with PMRA's MRLs, because EPA's tolerance is established in the entire crop group, 

not in separate subgroups. 

Codex has an existing MRL in tree nuts at 0.1 mg/kg, which is harmonized with the 

recommended tolerance of0.10 ppm in tree nut group 14-1 2. PMRA has an existing MRL in a 

large variety of tree nuts at 0.1 mg/kg, which is harmonized with the recommended tolerance of 

0.10 ppm in tree nut group 14-12. 

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2.3 Label Recommendations 

None. 

2.4 Submittal of Analytical Reference Standards (860.1650) 

The analytical reference standard for parent methoxyfenozide, with an expiration date of 28 July 

2018, is currently available in EPA' s National Pesticide Standards Repository (NPSR), per Email 

communication from Theresa Cole of the Biological and Economic Analysis Division's 

(BEAD's) Analytical Chemistry Branch (ACB) on 19 February 2015. The registrant is required 

to maintain reasonable amounts of the reference standards for methoxyfenozide and its 

metabolites in the NPSR as long as tolerances remain published in 40CFR § 180.544. When 

necessary, new reference standards, or updated certificates of analysis (CO As), should be sent to 

the ACB, which is located at Fort Meade, MD. It should be sent to the attention of either 

Theresa Cole or Thuy Nguyen at the address listed below, along with a letter of transmittal. 

Please note that the full 9-digit ZIP Code is required, or the mail will be returned to the 

registrant. 

USEPA 

National Pesticide Standards Repository 

Analytical Chemistry Branch/BEAD/OPP 

701 Mapes Road 

Fort George G. Meade, MD 20755-5350 

The letter of transmittal should include the assay of the standard, name of the analytical method 

used, a statement of principal impurities, purification procedures employed, storage 

requirements, and special precautions for safe handling. Replacement of standards, or updated 

CO As, may be required periodically if supplies are exhausted, if the standards expire, or if 

decomposition occurs during storage. Material Safety Data Sheets (MSDSs) must accompany all 

analytical standards as specified by the Occupational Safety and Health Administration (OSHA) 

in 29CFR §1910.1200. In addition to the parent compound, the metabolites included in the 

various tolerance expressions are currently available in the NPSR, as listed below with their 

respective expiration dates. 

Methoxyfenozide metabolite RH-117,236: 

Methoxyfenozide metabolite RH-141,518: 

Methoxyfenozide metabolite RH-151,055: 

Methoxyfenozide metabolite RH-152,072: 

13 August 2021 . 

27 July 2021. 

2 July 2018. 

15 July 2018. 

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3.0 Chemical Identity 

Methoxyfenozide is a diacylhydrazine insecticide used on a variety of crops for control of 

armyworms and other lepidopterous pest species. It mimics the action of the molting hormone of 

lepidopterous larvae, causing the larvae to undergo an incomplete and premature molt, which 

ultimately results in their death. The chemical structure and nomenclature of methoxyfenozide 

are listed in Table 3.1, and its physicochemical properties are presented in Table 3.2 (below). 

3.1 Nomenclature 

TABLE 3.1 Methoxyfenozide Nomenclature. 

Chemical structure H3C f'l3 

r CH3 Cll 

q--<-~ 0 0 ~ ~ ' 1-13C-O CH3 CH3 

Common name Methoxyfenozide 

Company experimental name RH-2485 

Molecular formula C22H2sN20 3 

Molecular weight 368.47 

IUPAC name N-t ert-butyl-N '-(3-methoxy-o-to I uoyl )-3 ,5-xy lo hydrazide 

CAS name 3-methoxy-2-methylbenzoic acid 2-(3 ,5-dimethylbenzoyl)-2-( I, Idimethylethyl)hydrazide 

CAS registry number 161050-58-4 

End-use product (EP) 2 lb ai/gal (240 g ai/L) flowabl e concentrate (FIC) formulation (Intrepid 2F; EPA 

Registration #62719-442). 

3.2 Physicochemical Characteristics 

TABLE 3.2 Physicochemical Pro lerties of Methoxyfenozide. 

Parameter Va lue Reference 

Me lting point/range (°C) 206.1 -208 D23 I 303, H. Podall, 19 

pH 7.0 May 1997 

Density {g/cm3) 0. 740 ± 0.0081 

Water solubility (mg/Lat 20°C) .., .., .),.) 

Solvent solubility {g/L at 20°C) N-heptane 1.87 

Xylene 3.38 

1,2-dichloroethane 36.72 

Methanol 192.92 

2-Propanol 50.22 

Vapor pressure (Pa at 25°C) 1.33 x JQ-5 

Dissociation constant, pK. None 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

TABLE3.2 Phvsicochemical Pro Jerties of Methoxvfenozide. 

Parameter Value Reference 

Octanol/water partition coefficient 3.72 ± 0.04 

(Log [Kow]) 

UV /visible absorption spectrum No absorption expected at A> 300 nm 

Methoxyfenozide is a solid under ambient conditions, and has a somewhat low volatility. The 

compound has a relatively low solubility in water, and moderate solubility in organic solvents. 

Its octanol/water partition coefficient suggests that accumulation of methoxyfenozide in fatty 

tissues is possible. 

3.3 Pesticide Use Pattern/Directions for Use (860.1200) 

Dow AgroSciences has requested that a new Section 3 use of the insecticide methoxyfenozide on 

chives be added to the label for Intrepid 2F (Registration #62719-442). Intrepid 2F is an FIC 

formulation containing 22.6% ai by weight, which is equivalent to 2 lb ai/gal. An example of the 

proposed label for Intrepid 2F was provided, and the proposed use directions therein are 

summarized in Table 3.3, below. 

TABLE3.3 Summarv of Proposed Use Directions for Methoxvfenozide on Chives. 

Application Type; Single Use Max. Max. pHJ2 Use Directions, Application 

Equipment1 Rate (lb Uses Per Seasonal Use (Days) Timing, and Limitations 

ai/A) Season Rate (lb ai/A) 

Foliar; ground or aerial 0.06-0.25 NS3 1.0 I Minimum RTI4 of I 0 days. May 

equipment. not be applied via chemigation . . . I. For ground appllcat1on, apply ma mm1mum of 10 gallons of water per acre (GPA) to young/small plants, or in a 

minimum of20 GPA to densely foliated or difficult to cover crops. For aerial application, apply in a 

minimum of 10 GPA. 

2. PHI = Pre-Harvest Interval. 

3. NS = Not Specified. 

4. RTI = Re-Treatment Interval. 

Conclusions: The use directions for application to chives are sufficient to allow for evaluation of 

the submitted residue data relative to the proposed use pattern. 

4.0 Metabolite/Degradate Residue Profile 

4.1 Nature of the Residue 

0258034; W. Wassell; 23 July 1999 

0251225; W. Wassell; 27 July 1999 

0259989; W. Wassell; 8 August 2000 

The nature of methoxyfenozide residues in primary crops is adequately understood, based on 

acceptable metabolism studies in cotton, apples, grapes and rice. Methoxyfenozide does not 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode 0425285 

undergo extensive metabolism in primary crops. HED has determined that the residue of 

concern (ROC), for both the tolerance expression and risk assessment in primary crops (and 

drinking water), is parent methoxyfenozide only. 

0269986; M.J. Nelson; 7 August 2002 

The nature of methoxyfenozide residues in rotational crops is adequately understood, based on 

acceptable metabolism studies in confined, limited field, and extensive field rotational crop 

studies. For enforcement purposes, the ROC for high-moisture rotational crops is the parent 

compound; the metabolites RH-151 ,055, RH-152,072, RH-117,236, RH-152,067, RH-1 31,157 

and RH-152,07 1 are also to be taken into account for risk assessment. For enforcement 

purposes, the ROCs for low-moisture rotational crops are the combined residues of parent and 

metabolites RH-151 ,055, RH-152,072 and RH-117,236; metabolites RH-152,067, RH-131 ,157 

and RH-152,071 are also to be taken into account for risk assessment. 

MARC Memo; 0258034 W. Wassell; 23 J uly 1999 

The nature of the residue in ruminants and poultry is adequately understood, based on the 

available metabolism studies in lactating goats, and laying hens, respectively. HED has 

determined that the ROC in milk and ruminant tissues (other than liver and kidney) is parent 

compound; in ruminant liver and kidney it is methoxyfenozide and its RH-141 ,518 metabolite. 

The residue of concern in poultry meat (muscle) and fat is parent methoxyfenozide. The residue 

of concern in eggs, poultry liver, and poultry meat byproducts is methoxyfenozide and its 

metabolite RH-141 ,5 18. 

4.1.1 Summary of Plant and/or Livestock Metabolism (860.1300) 

Data have been submitted and reviewed depicting the metabolism of methoxyfenozide in 

numerous crops and the environment. HED has determined the plant and livestock ROCs for 

purposes of tolerance enforcement and risk assessment; see Table 4.1.1 , below. 

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TABLE 4.1.1 Summary of Methoxyfenozide Metabolites and Degradates to be included in the Risk 

Assessment and Tolerance Expr ession. 

Matrix Residues Included in Risk Residues Included in Tolerance 

Assessment Expression 

Plants Primary Crops Parent methoxyfenozide Parent methoxyfenozide 

Rotational Crops Parent methoxyfenozide and Parent methoxyfenozide 

(High Moisture) metabolites, RH-151 ,055, RH-152,072, 

and RH- 117,236, RH-152,067, RH131, 157 and RH-152,07 1 

Rotational Crops Parent methoxyfenozide and Parent methoxyfenozide and 

(Low Moisture) metabolites, RH-151,055, RH-152,072, metabolites RH-151,055, RHand RH-117,236, RH-152,067, RH- 152,072, and RH-117,236 

13 1, 157 and RH-152,071 

TABLE 4.1.1 Summary ofMethoxyfenozide Metabolites and Degradates to be included in the R isk 

Assessment and Tolerance Expression. 

Matrix Residues Included in Risk Residues Included in Tolerance 

Assessment Expr ession 

Livestock Ruminant Milk, Parent methoxyfenozide Parent methoxyfenozide 

Meat and Fat 

Ruminant Liver Parent methoxyfenozide and metabolite Parent methoxyfenozide and 

and Other Meat RH- 141 ,518 metabolite RH-141,518 

Byproducts 

Poultry Meat and Parent rnethoxyfenozide Parent methoxyfenozide 

Fat 

Poultry Eggs, Liver Parent rnethoxyfenozide and Parent methoxyfenozide and 

and Other Meat metabolite RH-141 ,518 metabolite RH-141 ,518 

Byproducts 

Drinking Water Parent methoxyfenozide Not applicable 

Conclusions: The nature of the residue in plants and animals has been adequately delineated. 

4.1.2 Summary of Confined Rotational Crops (860.1850) 

0258034 W. Wassell; 23 July 1999 

0251225; W. Wassell; 27 July 1999 

0269986; M. J. Nelson; 7 August 2002 

The nature of methoxyfenozide residues in rotational crops is adequately understood, based on 

the available confined rotational crop study. Following three soil applications of 

14

C-methoxyfenozide at rates totaling 2.0 lb ai/A (IX rate), total radioactive residues 

accumulated at 0.01 ppm in mustard, radishes and wheat planted 31, 91 and 364 days after the 

last application. Methoxyfenozide was highly metabolized in rotational crops by oxidation, 

demethylation, and hydroxylation to non-conjugated metabolites, which were then conjugated 

with biomolecules, yielding bound residues and precursors in the sugar synthesis pathway. 

4.1.3 Summary of Rat Metabolism 

Risk Assessment Document 0388978; M. Collantcs; 23 May 2012 (PP#lE7842) 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

In the rat, 14C-radiolabeled methoxyfenozide was rapidly absorbed following gavage 

administration, with maximum peak plasma concentrations observed within 15 minutes of 

dosing. Peak plasma concentrations at 10 mg/kg ranged from 0.70-1.09 ppm in males, and 0.50-

0.59 ppm in females, depending on the ring location of the radio label. At 1000 mg/kg, peak 

levels were 26.11-35.52 ppm in males, and 21 .92-29.74 ppm in females. Plasma elimination 

was biphasic, with an a-phase T112of0.2-0.6 hours, and a P-phase T112 of15.2-35.6 hours, and 

showed some variation with radiolabel location. The total plasma elimination rate was longer for 

the high dose compared to the low dose animals, suggesting metabolic pathway saturation, and 

the effect was more prominent in female rats. Radioactivity was extensively distributed among 

tissues, with the highest concentrations at Cmax (0.25 hr) observed in the intestinal tract, stomach, 

liver and residual carcass. Enterohepatic circulation was observed. 

Methoxyfenozide did not show a potential for bioaccumulation. By 5 days post-treatment, the 

highest levels were observed in the liver and carcass, but tissue radioactivity in all tissues was 

insignificant by that time. Excretion of radiolabel was essentially complete by 48 hours postdosing. Based on the minimal level of radioactivity in tissues at 72 hours, absorption was 

estimated to be at least 62-70% of the administered dose (biliary plus urinary excretion). The 

major route of excretion was in the feces (86-97% of the administered dose), with 5-13% of the 

dose excreted in the urine. Significant dose- or sex-dependent differences in metabolic 

disposition were not observed. Methoxyfenozide was extensively metabolized. The major 

routes of metabolism involved o-demethylation and oxidative hydroxylation of the A-ring 

phenyl and/or B-ring methyl groups, followed by glucuronic acid or sulfate conjugation. 

In addition to the parent compound, seven major metabolites were identified in excreta. These 

included RH-131 , 157, RH-141 ,58 1 and RH-117,236, metabolites also identified in residues in 

crops and/or livestock. Up to 25 metabolites were isolated from urine, but the majority 

represented <1-2% of the radioactive dose. Up to 16 metabolites were identified in the feces, 

including the parent compound, with only six containing 2:5% of the administered radiolabel. 

The major fecal metabolites in all groups were products of Phase I 0-demethylation and 

oxidative hydroxylation on the A-ring and, to a lesser extent, the B-ring. Levels of excreted 

parent compound in the feces were greater in animals receiving 1000 mg/kg test material (30-

39% of dose) when compared to the 10 mg/kg groups (14-26% of dose), consistent with 

saturation of absorption. In the bile, up to 24 metabolites were detected, with the primary 

metabolite (13-18% of dose) being derived by glucuronide conjugation at the o-demethylated 

alpha ring. 

4.1.4 Summary of Environmental Degradation 

EFED Memo; 0388876; K. Milians; 17 August 2011 

Methoxyfenozide is very persistent (T 112 = 1 to 3 years in soil and water), and moderately mobile 

(Koc = 219-922 L/kgoc in various soils). It is stable to photolysis and hydrolysis, is not 

significantly volatile, and degrades only very slowly by microbial activity. Degradates are 

predominantly RH-117,236 and RH-131 , 154, but these are only present at low concentrations. 

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Because of its resistance to degradation and its mobility, methoxyfenozide has the potential to 

accumulate and to move off the site of appli cation by leaching and erosion/runoff, resulting in 

ground- and surface-water contamination. 

5.0 Residue Profile 

5.1 Residue Analytical Methods (860.1340) 

5.1.1 Data Collection Methods 

MRID #49420201 

The data collection method used for chive sample analysis was derived from Dow AgroSciences 

method ORM: 02.25, Determination of Residues of Methoxyfenozide in High Moisture Crops by 

Liquid Chromatography with Tandem Mass Spectromefly Detectfon, S.L. Byrne and M.J. 

Hastings, 4 October 2002; and Rohm and Haas Report Number 34-98-87, titled Tolerance 

Enforcement Method for Parent RH-2485 in Pome Fruit. 

Residues of methoxyfenozide were extracted from fresh and dried chives by homogenization 

with 90% methanol/ I 0% 0.1 N HCl, which was then shaken and centrifuged. The extract was 

purified by solid phase extraction (SPE) using an Evolute ABN SPE cartridge. The extracts were 

then analyzed by liquid chromatography with tandem mass spectrometric detection 

(LC/MS/MS). Based on recoveries from samples fortified at the lowest level of method 

validation (LLMV), the limit of detection (LOD) and LOQ in fresh leaves were 0.0016 ppm and 

0.0048 ppm, and in dried leaves were 0.0146 and 0.0438 ppm, respectively. Analytical sets 

typically consisted of calibration standards, unfortified controls, fortified controls, and treated 

samples. A calibration standard was injected at the beginning and end of each analytical set. 

Control samples were fortified and analyzed both prior to, and concurrently with, the field trial 

samples. Method validation recoveries of methoxyfenozide from samples of fresh chives 

fortified at 0.010 ppm to I 0.0 ppm ranged from 83 to 91 % (86 ± 3%; n = 9). Concurrent 

recoveries from samples of fresh chives fortified with methoxyfenozide at 0.010 ppm to 20.0 

ppm ranged from 84 to 98% (92 ± 6%; n = 7). Method validation recoveries of methoxyfenozide 

from samples of dried chives fortified at 0.050 ppm to 50.0 ppm ranged from 85 to 89% (87 ± 

2%; n = 9). Concurrent recoveries from dried chives fortified at 0.050 ppm to 200 ppm ranged 

from 81 to 106% (92 ± 11 %, n = 7). Recoveries were within the generally recognized acceptable 

range of 70-120%. The fortification levels used in concurrent method recovery were adequate to 

bracket expected residue levels. 

Method validation and concurrent recovery results are summarized in Table 5.1.1 below. 

Methoxyfenozide residues in control samples of fresh and dried chives were <0.010 ppm and 

<0.050 ppm, respectively. A five-point standard curve was generated by injecting constant 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

volumes of standard solutions each time an analytical set was run. The correlation coefficient 

was always reported to be 2::0.999. 

TABLE 5.1.l Summary of Methoxyfenozide Recoveries from Chive Leaves. 

Matrix Spike level Sample size Type of Recoveries Mean ± Std. 

(ppm) (n) Recovery (%) eviat (%)~ 

Chives (Fresh 0.010 6 MVR1 91, 88, 88 89 ± 2 

Leaves) CR2 97,97,98 97 ± I 

0.300 3 MYR 85, 84, 84 84 ± I 

2.00 3 SSCR3 89,93, 92 91±2 

10.0 4 MYR 84,83, 84 84 ± I 

CR 91 91 

20.0 3 CR 88,84, 86 86 ± 2 

Chives (Dried 0.050 6 MYR 87,88, 89 88 ± 1 

Leaves) CR 106, 102, 103 104 ± 2 

2.00 6 MVR 86,85, 85 85 ± 1 

SSCR 90, 88, 88 89 ± 1 

50.0 4 MYR 86, 85, 88 86 ± 2 

CR 92 92 

200 ... 

.) CR 82, 81 , 81 81 ± 1 

I. MVR = Method Validation Recovery. 

2. CR = Concurrent Recovery. 

3. SSCR = Storage Stability Concurrent Recovery. 

4. Standard deviation is not calculated for sample sets with n < 3. 

Conclusions: Adequate method validation data have been submitted for the LC/MS/MS method 

used for the determination of methoxyfenozide residues in fresh and dried chive leaves. No 

additional data are required in support of this data collection method. 

5.1.2 Multi-Residue Methods (860.1360) 

0 251225; W. Wassell; 27 July 1999 

Data concerning the recovery of methoxyfenozide using the FDA multi residue method protocols 

(PAM Volume!) were previously submitted to, and reviewed by, HED. Methoxyfenozide was 

not recoverable by any of these procedures. The data were previously forwarded to FDA for 

evaluation, and for the updating of PAM Volume 1. It was also noted that the European Food 

Safety Authority (EFSA} has concluded that the multiresidue QuEChERS method, combined 

with LC/MS/MS, is adequate for tolerance enforcement in plant and animal commodities (EFSA, 

2014). 

5.1.3 Tolerance Enforcement Methods 

0358341; D. Rate; IO J une 2009 

Several HPLC/UV and HPLC/MS methods are available for enforcing tolerances of 

methoxyfenozide in primary crops, Method TR 34-96-88, Method TR 34-98-87, Method TR 34-

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode 0425285 

00-38, Method TR 34-00-1 07, Method TR 34-00-1 09, and Method TR 34-99-74. Adequate 

method validation, radio-validation, and independent laboratory validation (IL V) data have been 

provided for these methods. Successful petition method validation (PMV) trials were conducted 

on Methods TR 34-96-88 and TR 34-98-87, and BEAD's ACB concluded that PMV trials were 

not required for the other methods, since they are similar to the validated methods. 

For each of these methods, residues of methoxyfenozide are extracted with acidic aqueous 

methanol, filtered, and diluted with 10% sodiwn chloride. Extracts are then purified by 

sequential liquid-liquid partitioning with hexane and dichloromethane (DCM). Residues in the 

DCM fraction are further purified by elution through one or more of the following colwnn types: 

basic alumina, silica gel, carbon, Florisil, or C1s. Residues in the final eluate are concentrated, 

re-dissolved in ACN/water, and analyzed by reverse-phase HPLC using UV (240 nm) or MS 

(m/z 367) with external standards. The LOQ for methoxyfenozide is 0.01-0.05 ppm, depending 

on the plant commodity. 

An adequate enforcement method is also available for determining the ROCs in rotated crops. 

Method TR 34-00-41 includes an HPLC/UV method that determines methoxyfenozide residues 

in high-moisture rotational crops, and an HPLC/MS method that determines residues of 

methoxyfenozide and its metabolites RH-117,236, RH-151 ,055 and RH-152,072 (determined as 

RH-151,055) in low-moisture rotational crops. Adequate method validation, radio-validation, 

and IL V data have been submitted for this method, and ACB concluded that a PMV trial was not 

needed for this method owing to its similarity to Method TR 34-98-87. 

5.2 Storage Stability (860.1380) 

MRID #49420201 

Chive samples were stored frozen for up to 119 days (fresh leaves) and 122 days (dried leaves) 

after collection. A freezer storage stability study was conducted using samples of chives 

fortified with 2.00 ppm methoxyfenozide, and stored for 110 days (fresh leaves) and 112 days 

(dried leaves). Concurrent recoveries of methoxyfenozide during analysis of storage stability 

samples of fresh leaves and dried leaves ranged from 89 to 93% (91 ± 2%; n = 3) and 88 to 90% 

(89 ± 1 %; n = 3), respectively. Recoveries from stored chives fortified with methoxyfenozide at 

2.00 ppm ranged from 91 to 93% (92 ± 1 %; n = 3) and 86 to 87% (86 ± 1%;n=3) for fresh and 

dried chives, respectively (see Table 5.2.1, below). 

TABLE 5.2.1 Summary of Storage Conditions. 

Matrix Storage Actual Stor age interval of Demonstrated Storage Stability 

Temperature (°C) Duration <Days)* Storae:e Stability (Days) Recoveries (%) 

Chives <-20 119 110 91 , 91 , 93 

(Fresh Leaves) 

Chives <-20 122 112 86, 86, 87 

(Dried Leaves) 

* Interval from harvest to analysis; samples were analyzed within 1-4 days of extraction. 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

Conclusions: There are no storage stability issues, and no corrections for potential decline 

during storage are needed in reviewing the residue data submitted for chives. 

5.3 Residue Data 

5.3.1 Crop Field Trials (860.1500) 

MRJD #49420201 

IR-4 has submitted field trial data for methoxyfenozide on chives. Three field trials were 

conducted in the US, encompassing NAFTA Zones 2 (MD; 1 trial) and 10 (CA; 2 trials) during 

the 2012 growing season. 

At each field trial site, chives were treated with four foliar applications of methoxyfenozide, as 

Intrepid 2F (EPA Registration# 62719-442), an FIC formulation containing 22.6% ai by weight, 

equivalent to 2 lb ai/gal. Foliar broadcast applications were utilized, except at one of the CA 

trial sites, where treatments were foliar directed applications. All foliar applications were made 

at a targeted rate of 0.25 lb ai/ A per application, for a total seasonal use rate of approximately 1.0 

1 b ai/ A. Applications were made at R Tls of 8-11 days, with a PHI of 1 day. In the two 

California field trials, untreated samples were harvested on the day of the last application. An 

NIS adjuvant was included in each tank mix at all trial sites. 

The chive field trial residue results are summarized in Table 5.3.1, below. Following four foliar 

broadcast/directed applications of the 2 lb ai/gal FlC formulation of methoxyfenozide at 

approximately 1.0 lb ai/ A, residues of methoxyfenozide in fresh and dried chive leaves harvested 

at a 1-day PHI, were 5.7-13 ppm and 12-118 ppm, respectively. 

TABLE 5.3.1 Summary of Residue Data from Chive Field Trials with Methoxvfenozide. 

Commodity Total Use PHI Residue Levels (ppm' 1 

Rate {lb ai/A) (Days) n Min. Max. HAFT2 Median Mean 

Chives (Fresh Leaves) 0.994-1.00 1 6 5.7 13 12.5 7.1 8.6 

Chives (Dried Leaves) I 6 12 118 115 64 64 

I. Except for sample minimum and maximum, values reflect per trial averages; n = number of field trials. 

2. HAFT = Highest Average Field Trial. 

Std. Dev. 

3.1 

46 

Conclusions: The submitted crop field trial data are adequate, and support the removal of the 

exception for chives in the existing herb subgroup 19A tolerance, addition of an exception for 

chive fresh leaves to the existing green onion subgroup 3-07B tolerance, and establishment of a 

stand-alone tolerance in chive fresh leaves at 30 ppm. 

5.3.2 Field Rotational Crops (860.1900) 

Label directions for methoxyfenozide (Intrepid 2F) currently specify that crops with registered 

uses may be replanted at any time, and all other food or feed crops may be replanted 7 days after 

Page 18 of25 
Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode 0425285 

the last application. Adequate limited and extensive rotational crop field trials are available that 

support these rotational crop restrictions. 

There are no rotational crop issues associated with the proposed use on chives. 

5.3.3 Processed Food and Feed (860.1520) 

MRID #49420201 

The processed commodity for fresh chives is dried chives, although these are considered a RAC 

under herbs and spices group 19. Samples of dried chives were produced at the field trial sites, 

and subsequently analyzed along with the fresh chive samples. 

5.3.4 Meat, Milk, Poultry and Eggs (860.1480) 

No significant livestock feedstuffs are associated with the proposed new use on chives. 

Conclusion: Reassessment of the currently established livestock tolerances is not required for 

this petition. 

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 

The data submitted in support of the current action (PP#4E8298) along with previously reviewed 

data, are adequate for purposes of risk assessment and tolerance assessment for the proposed use 

under review. Maximum residues of methoxyfenozide are expected to occur at moderate to high 

levels (up to 30 ppm in fresh chive leaves, and up to 300 ppm in dried chive leaves) from the 

new use on chives proposed in the current petition. 

Methoxyfenozide residues generally tend to decline or remain stable with increasing PHI, and do 

not increase to any significant degree. Following foliar applications, methoxyfenozide is present 

primarily as surface residues; translocation does not appear to be extensive. In general, 

methoxyfenozide residues do not tend to concentrate in processed fractions, other than via 

dehydration or from surface residues. 

Residues of methoxyfenozide are not expected to accwnulate above the LOQ in rotational crops 

planted at PB Is of 7 days following application of methoxyfenozide to primary crops. 

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6.0 Tolerance Derivation 

HED recommends in favor ofIR-4's proposal to remove the chive exception to the existing herb 

subgroup 19A except chive tolerance, but against IR-4's proposal to replace it with an exception 

for fresh chive leaves, which are not included in subgroup 19A (fresh chives are included in 

green onion subgroup 3-07B). The chive field trial data support a tolerance of 30 ppm in fresh 

chives, and 300 ppm in dried chives, based on input of the residue data into the OECD tolerance 

calculation procedure. 

Instead of the proposed tolerance in chive fresh leaves (30.0 ppm), HED recommends 

establishing the tolerance at 30 ppm. The Agency establishes tolerances using whole numbers 

for tolerances of I 0 ppm or more, per the OECD's User Guide ENV/JMIMON0(2011)2 for the 

OECD tolerance calculation procedure. 

Upon establishment of the recommended tolerance in herb subgroup 19A, the existing tolerance 

in herb subgroup 19A except chive should be removed (40CFR §180.544[a][l]). 

Upon establishment of the recommended tolerance in chive fresh leaves at 30 ppm (40CFR 

§180.544[a](l]), the existing tolerance for indirect or inadvertent methoxyfenozide residues in 

rotational crop chives at 4.5 ppm should be removed ( 40CFR § 180.544[ d](2]). 

Upon establishment of the recommended tolerance in green onion subgroup 3-07B except chive 

fresh leaves, the existing tolerance in green onion subgroup 3-07B should be removed ( 40CFR 

§180.544[a](1]). 

Upon establishment of the proposed tolerance in tree nut group 14-12, the existing tolerances in 

tree nut group 14 and pistachio should be removed (40CFR §180.544(a][l]). 

Upon establishment of the proposed tolerance in stone fruit group 12-12 except fresh prune 

plum, the existing tolerance in stone fruit group 12 except fresh prune plum should be removed 

( 40CFR § 180.544( a] [I]). 

An International Residue Limit Status sheet is appended as Attachment I. Data sets and results 

from the OECD tolerance calculation procedure for fresh and dried chive leaves are appended as 

Attachment 2. 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

References 

PP#8F5004 & PP#8F5006; Methoxyfenozide. Conclusions of the 7113199 Meeting of the 

Metabolism Assessment Review Committee.; 0258034; W. Wassell; 23 July 1999. 

PP#8F5004 & PP#8F5006: Methoxyfenozide on Cotton and the Pome Fruit Crop Group. 

Evaluation of Metabolism Data, Residue Data, and Analytical Methodology.; D24943 8, 

0249458, D251218, 0 25 1225; W. Wassell; 27 July 1999. 

PP9F06033: Section 3 Request for Use of Methoxyfenozide on Grapes and Fruiting Vegetables. 

Review of Analytical Methods and Residue Chemistry Data.; D259989; W. Wassell; 8 August 

2000. 

PP#OF06201: Methoxyfenozide inion Various Rotational Crops. Residue Chemist1y Review.; 

0269986; M.J. Nelson; 7 August 2002. 

Methoxyfenozide. Human Health Risk Assessment to Support Proposed Uses on Root Vegetables 

and Citrus.; 0388978; M. Collantes; 23 May 2012. 

Drinking Water Assessment for the IR-4 New Use Petitions for the Use of Methoxyfenozide on 

Root Vegetables for Crop Subgroup 1 B (Except Sugar Beets) and Citrus Crop Group 10.; 

0388876; K. Milians; 17 August 2011 

Methoxyfenozide. Petition for Uses and Tolerances on the Citrus Crop (Group 10), Dried 

Shelled Peas and Beans, except Soybean (Subgroup 6C), Popcorn, and Pomegranate. Summary 

of Analytical Chemislly and Residue Data.; 0358341 ; 0 . Rate; 10 June 2009 

Attachments 

Attachment 1 : International Residue Limit Status sheet. 

Attachment 2: OECO Tolerance Assessment Calculations. 

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Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode D425285 

Attachment 1: International Residue Limit Status. 

Methoxyfenozide (PC Code 121027) 

Summary of US Tolerances and International Maximum Residue Limits. 

Residue Definitions 

US (40CFR ~180.544) Canada Codex 

Primary crops: Methoxyfenozide All food crops, livestock fat, meat and Methoxyfenozide. The 

(3 -methoxy-2-methylbenzoic acid 2- meat byproducts: 3-methoxy-2- residue is fat-soluble, but is 

(3 ,5-dimethylbenzoyl)-2-( I , I- methylbenzoic acid, 2-(3,5- not classified as fat-soluble 

dimethylethyl) hydrazide). dimethylbenzoyl)-2-( 1, I- with respect to its 

dimethylethyl)hydrazide. distribution in milk. 

Livestock: The sum of 

methoxyfenozide and its glucuronide Livestock kidney a nd liver: 3-methoxy-2-

metabolite (3 -((2-( I , 1-dimethylethyl)- methylbenzoic acid, 2-(3,5-

2-(3 ,5-dimethy lbenzoyl)-hydrazino) dimethylbenzoyl)-2-( I, Icarbonyl)-2-methylphenyl-13-D- dimethylethyl)hydrazide, including the 

glucopyranuronic acid,), calculated as metabolite 3-((2-( I, l-dimethylethyl)-2-(3,5-

the stoichiometric equivalent of dimethylbenzoyl)-hydrazino) carbonyl)-2-

methoxyfenozide. methylphenyl-13-D-g,lucopyranuronic acid. 

Commodity2 Tolerance Commodity MRL Commodity MRL 

(ppm)l (mg/kg) (mg/kg) 

Onion, green, subgroup 5.0 Beltsville bunching onions, 5 

3-078 elegans hosta, fresh Chinese 

chive leaves, chive leaves, fresh 

onions, fritillaria leaves, green 

onions, kurrats, lady's leek, 

leeks, macrostem onions, shallot 

leaves, tree onion tops, Welsh 

onion tops, wild leeks 

Herb subgroup I 9A 400 Fresh leaves (angelica, balm, 80 

basil, borage, cilantro, clary, 

costmary, culantro, curry, 

dilweed, lemongrass, lovage, 

rosemary, rue, sage, summer 

savory, sweet bay, tansy, 

tarragon, thyme, winter savory, 

winter green, woodruff, 

wormwood); fresh (bumet, 

horehound, hyssop tops, 

lavender, marigold, marjoram, 

nasturtium leaves and flowers) 

Page 22 of25 
Methoxyfenozide Summary of Analytical Chemistry and Residue Data DP Barcode 0425285 

Metboxvfenozide (PC Code 121027) 

Summary of US Tolerances and International Maximum Residue Limits. 

Residue Definitions 

US (40CFR ~180.544) Canada Codex 

Fruit, stone, group 12- 3.0 American plums, Apricots, 0.7 Stone fruit 2 

12, except plum, prune, beach plums, Canada plums, 

fresh cherry plums, chicksaw plums, 

damson plums, fresh prune 

plums, Japanese apricots, 

Japanese plums, jujubes, 

klamath plums, plumcots, 

plums. sloes 

Black cherries, capulins, 6 

nanking cherries, nectarines, 

peaches, sweet cherries, tart 

cherries 

Nut, tree, group 14-12 0.10 African tree nuts, almond nuts, 0.1 Tree nuts 0.1 

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 horsechestnuts, macadamia nuts, 

mongongo nuts, monkey-pot 

nuts, monkey puzzle nuts, Okari 

nuts, Pachira nuts, peach palm 

nuts, pecan nuts, pequi nuts, Pili 

nuts, pine nuts, pistachio nuts, 

Sapucaia nuts, tropical almond 

nuts, yellow horn nuts 

Completed: M. Negussie; 26 February 2015. 

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

2. Includes only commodities of interest for this action. 

3. Tolerance values are those recommended by HED, not those proposed by the petitioner. 

Page 23 of25 
Methoxyfenozide Summary of Analytical Chemistry and Residue Data 

Attachment 2: OECD Tolerance Assessment Calculations. 

Fresh Chive Leaves 

Residues 

(ppm) 

12 . 500 

6 . 700 

6 . 550 

Methoxyfenozide 

Fresh chive 

USA 

1.0 lb ai/A, 1-day PHI 

Total number of data (n) 

Percentage of censored data 

Number of non- censored data 

Lowest residue 

Highest residue 

Median residue 

Mean 

Standard deviation (SD) 

Correction factor for censoring {CF) 

Proposed MRL estimate 

- Highest residue 

- Mean + 4 SD 

- CF x 3 Mean 

Unrounded MRL 

Rounded MRL 

High uncertainty of MRL estimate. 

[Small dataset] 

Page 24 of25 

3 

0% 

3 

6.550 

12.500 

6.700 

8.583 

3.393 

1 .000 

12 . 500 

22. 154 

25 . 750 

25 . 750 

30 

DP Barcode D425285 
Methoxyfenozide Summary of Analytical Chemistry and Residue Data 

Dried Chive Leaves 

Residues (ppm) 

115.000 

64.000 

12 . 500 

Methoxyfenozide 

Dried chive 

USA 

1.0 lb ai/A, 1-day PHI 

Total number of data (n) 

Percentage of censored data 

Number of non-censored data 

Lowest residue 

Highest residue 

Median residue 

Mean 

Standard deviation (SD) 

Correction factor for censoring (CF) 

Proposed MRL estimate 

- Highest residue 

- Mean + 4 SD 

- CF x 3 Mean 

Unrounded MRL 

Rounded MRL 

High uncertainty of MRL estimate . 

[Small dataset] 

Page 25 of25 

3 

0% 

3 

12.500 

115.000 

64 . 000 

63.833 

51. 250 

1.000 

115. 000 

268 .8 34 

191.500 

268 .834 

300 

DP Barcode D425285 
Methoxyfcnozide/62719-442/PC Code I 2 I 027/Dow AgroSciences/627 19 

DACO 7.4.1 /0PPTS 860.1500/0ECD !IA 6.3.1 , 6.3.2. 6.3.3 and lllA 8.3. 1. 8.3.2. 8.3.3 

Crop Field Trial/Residue Decline - Chives (Leaves) 

Primary Evaluator 

Peer Reviewer 

Approved by 

STUDY REPORTS 

Sergei I. Usachenko, Ph.D .. 

Environmental Scientist, 

California Department of Pesticide Regulation. 

Theresa Ratto, Ph.D., 

Senior Environmental Scientist, (Specialist) 

California Department of Pestic ide Regul ation. 

William T. Drew, Chemist, Risk Assessment 

Branch TI (RAB2), Health Effects Division 

(HED) 7509P, Office of Chemical Safety and 

Pollution Prevention (OCSPP). Office of 

Pesticide Programs (OPP). USEPA 

Date: December 23, 2014 

Date: December 23, 2014 

Date: 28 January 2015 

MRID #49420201. Kenneth S. Samoil (2013) Methoxyfenozide: Magnitude of the Residue on 

Chives. IR-4 PR Number: 07240. Unpublished study prepared by Interregional Research 

Project Number 4 (IR-4). 129 pages. 

EXECUTIVE SUMMARY 

IR-4 has submitted field trial data for methoxyfenozide on chives. Three field trials were 

conducted in the US encompassing EPA regions 2 (MD; I trial) and 10 (CA; 2 trials) during the 

20 12 growing season. 

At each field trial site. chives were treated with four foliar applications of 

methoxyfenozide. as Intrepid 2F (EPA Registration # 627 19-442). a flowable concentrate (F) 

formulation containing 22.6% active ingredient (ai) by weight. equi valent to 2 pounds of ai per 

gallon (lb ai/gal). Foliar broadcast applications were utilized, except at trial site 07240.12-

CA * 17. where treatments were foliar directed applications. All foliar applications were made at 

a targeted rate of 0.25 lb ai per acre (lb ai/A) per application. for a total seasonal use rate of 

approximately 1.0 lb ai/A. Applications were made at re-treatment intervals (RTis) of 8-11 

days. with the last application one day before harvest. Tn the two California field trials, 

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Crop Field Tria l/Residue Decline - Chives (Leaves) 

untreated samples were harvested on the day of the last application. A non-ionic surfactant (NIS) 

adjuvant was included in each tank mix at all trial sites. 

Sample analysis for residues of methoxyfenozide was conducted by the IR-4 Western 

Region Laboratory at the University of California, Davis, California. The analytical method was 

adequate for data collection, and was derived from Determination of Residues of 

Methoxyfenozide in High Moisture Crops by Liquid Chromatography with Tandem Mass 

Spectrometty Detection, S.L. Byrne and M.J. Hastings, Dow AgroSciences method GRM: 02.25, 

dated 4 October 2002; and Rohm and Haas Report #34-98-87, titled Tolerance Enforcement 

Method for Parent RH-2485 in Pome Fruit. The reported limit of detection (LOO) and limit of 

quantification (LOQ) for methoxyfenozide on fresh leaves were 0.0016 ppm and 0.0048 ppm, 

respectively. The reported LOO and LOQ for methoxyfenozide on dry leaves were 0.0146 ppm 

and 0.0438 ppm, respectively. The lowest levels of method validation (LLMVs) for 

methoxyfenozide on chives were 0.010 ppm (fresh leaves) and 0.050 ppm (dried leaves). 

The maximum freezer storage duration for field-treated samples in this study was 119 

days for fresh leaves, and 122 days for dried leaves. A storage stability study was conducted in 

conjunction with this study with fortified samples that were kept frozen for 110 days (fresh 

leaves) and 112 days (dried leaves). 

The results from the chives field trials show that the maximum methoxyfenozide residues 

following a total seasonal application rate of approximately 1.0 lb ail A, and a pre-harvest interval 

(PHI) of I day, were 13 ppm and 118 ppm in fresh and dried leaves, respectively. A residue 

decline study was not conducted. 

STUDY/WAIVER ACCEPT ABILITY /DEFICIENCIES/CLARIFICATIONS 

Under the conditions and parameters used in the study, the chives field trial residue data 

are classified as scientifically acceptable. The acceptability of this study for regulatory purposes 

is addressed in the forthcoming USEPA Residue Chemistry Summary Document (DP Barcode 

0425285). 

COMPLIANCE 

Signed and dated Good Laboratory Practice (GLP), Quality Assurance, and Data 

Confidentiality statements were provided. The following deviations from GLP regulatory 

requirements were listed: 

1. Weather/in-igation and soil characterization at the field sites. 

2. Test site history at the field sites. 

3. Cultural practices dating back to harvest of the previous crop, and maintenance fertilizer 

and pesticide applications during the field trial year. 

4. The pH strips used to measure the acidity of the can·ier in the MD04 field trial. 

5. Residue sample weighing equipment in the field trials. 

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Crop Field Trial/Residue Decline - Chives (Leaves) 

6. The data collected by HOBO temperature logger for the test substance storage in the two 

California trials for the period April I st through June pt, 20 l 2 was lost prior to being 

printed. The storage temperatures for the period were estimated by obtaining copies of 

the temperature data from a similar storage unit located at the same research farm. 

However, none of these deviations had a negative impact on the validity of the study. 

A. BACKGROUND INFORMATION 

Methoxyfenozide belongs to the diacylhydrazine class of chemical insecticides, and has a 

novel mode of action for control of armyworms and other Lepidopterous pest species on a 

variety of crops. The chemical mimics the action of the molting hormone of Lepidopterous 

(moths, butterflies) larvae. Upon ingestion, the larvae undergo an incomplete and premature 

molt, which ultimately results in their death. 

Methoxyfenozidc is currently registered to Dow AgroSciences. The applicant has 

submitted field trial data on chives (leaves). The nomenclature and physicochemical properties 

of methoxyfenozide are presented below in Tables A. I and A.2, respectively. 

TABLE A.I Test Compou nd Nomenclature. 

CH3 Q-11° o~ --

Mcthoxy!Cnozidc 

c\ 1c \ j N-N 

I \ / CH3 

H3C-O CH3 H /C CH 3 

H3C \ 

CH3 

Common name Methoxyfenozide 

Company experimental name Rll-2485 

Molecular formula CnH2sN203 

Molecular weie.ht 368.47 

IUPAC name N-tert-butyl-.V "-(3-mcthoxy-o-toluoyl)-3.5-xylohydrazidc 

CAS name 3-rncthoxv-2-methvlben?.Oic acid 2-(3.5-dimethvlbenzovl)-2-( 1.1-dimethylcthyl)hvdrazidc 

CAS# 161050-58-4 

End-use product (EP) Intrepid 2F Insecticide (EPA Registration #62719-442) 

TABLEA.2 Physicochemica l Properties of Methoxyfenozide. 

Parameter Value Reference 

Mcltine. point/ran!?,C 206.1-208 0231303: 11. Podall: 19 May 1997 

pH 7.0 

Density {e./cm3) 0. 7-10 ± 0.0081 

Water solubilitv ( mg/L 20°C) 3.3 

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Crop Field Trial/Residue Decline - Chives (Leaves) 

TABLE A.2 Physicochemical Prope r ties of Methoxyfenoz ide. 

Parameter Value Reference 

Solvent solubility (g/L at 20°C) N-!-leptane 1.87 

Xylene 3.38 

1.2-dichlorocthane 36.72 

Methanol 192.92 

2-Propanol 50.22 

Vaoour orcssurc at 25°C 1.33 x I Q-5 Pa 

Dissociation constant (pK.) Not applicable 

Octanol/water oartition coefficient (Log I Kow I) 3.72 ± 0.04 

UV /visible absorption spectrum s 55313 at 203 nm European Commission; 

SANC0/ 10384/202 - rev. 4; 7 

October 2004 

B. EXPERIMENT AL DESIGN 

B.l. Study Site Information 

TABLE B.1.1 Trial Site Conditions. 

Trial Identification Number; Soil characteristics 

Location (City, State/Year) Type % OM pH CEC (meQ/g) 

07240. 12-CA * 17; Sal in as, CA/2012 Sandy Loam 1.8 6.5 8.9 

07240. 12-CA* l 8; Salinas. CA/2012 Sandy Loam 1.7 6.8 9.5 

07240. 12-MD04; Salisbury. MD/2012 Loamy Sand 1.3 6.1 3.3 

The actual weather conditions during the residue study period were generally considered 

within average historical values for all trial sites. Irrigation was used to supplement rainfall as 

needed. The application use pattern is summarized in Table B.1 .2, below. 

TABLE B.1.2 Study Use Pattern. 

Application 

Trial ID#, Location EP1 Spray Tota l Tank Mix (City, State)/Year Method/Timing (G rowth Stage) Volume Rate RTI Rate 

(GPA)2 (lb ai/A) (days) (lb ai/A) Adjuvants 

I. Foliar directecl/3-4 tnae leaves 42 0.250 - 07240. 12-CA * 17. Intrepid 2. Foliar directed/4-5 true leaves 42 0.248 IO 

1.00 R-11 NIS Salinas. CA/20 12 2F 3. Fol iar directecl/4-6 true leaves 48 0.249 9 

4. Foliar directed/6-9 tnac leaves 51 0.257 11 

I. Foliar broadcast /3-5 true leaves 26 0.247 -

07240. 12-CA * 18, Intrepid 2. Foliar broadcast /4-5 true leaves 27 0.249 9 

0.998 R- 11 NIS Salinas. CA/20 12 2F 3. Foliar broadcast /5-8 true leaves 29 0.252 11 

4. Foliar broadcast /6-1 0 true leaves 30 0.250 9 

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Crop Field Trial/Residue Decline - Chives (Leaves) 

TABLE B.1.2 Study Use Pattern. 

Application 

Trial ID#, Location EP1 Spray Total 

(City, State)Near Rate RT I Methodffiming (Growth Stage) Volume (days) Ra te 

(GPA)2 (lb ai/A) (lb a i/A) 

I. Foliar broadcast/Full bloom 30 0.248 -

07240. 12-MD04. Intrepid 2. Foliar broadcast/End of bloom JO 0.248 10 

0.994 Salisbury. MD/2012 2F 3. Foliar broadcasl/Post bloom 30 0.248 11 

4. Foliar broadcast/Post bloom 30 0.250 8 

I. EP = End-use Product. 

2. GP/\ = Gallons Per Acre. 

TABLE B.1.3 Tria l N umbe rs a nd Geographica l Locations 

Chives 

NA FTA Growing 

Z Requested ones Submitted 

us 

I 

IA 

2 l 

3 

-I 

5 

SA 

58 

6 

7 

7A 

8 

9 

10 2 

11 

12 

13 

14 

15 

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Tank M ix 

Adj uvants 

De-Fae 820 

NIS 

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Crop Field Trial/Residue Decline - Chives (Leaves) 

TABLE B. 1.3 Tria l Numbers a nd Geogra phical Locations 

I Chives 

NAFTA Growing 

Zones 

I 

Requested 

Submitted 

us 

16 

17 

18 

19 

20 

21 

- Total 3 Any3 

B.2. Sample Handling and Prepa ration 

At each trial site, untreated chives (leaves) were harvested before treated chives. Treated 

samples of fresh chives and chives for drying were collected one day following the final 

application. In the two California trials, the untreated samples were harvested on the day of the 

last application. Handfuls of chives leaves were cut near the soil line from at least 12 areas of 

plot, avoiding the row ends and outer rows. Dead and senesced leaves were removed. Sample 

bags containing chives were placed and held in separate coolers (treated and untreated) with blue 

ice. Samples of fresh chives were placed in frozen storage on the day of harvest. In order to 

obtain dry chives, in each trial the samples were held in a dryer for approximately 24 hours and 

then placed in frozen storage. All treated samples from each site were placed in frozen storage 

within 50 minutes of sampling and were shipped frozen to the analytical laboratory by ACDS 

freezer truck, arriving frozen and intact at the IR-4 Western Region Laboratory (Davis, CA). 

Upon anival at the analytical laboratory, the samples were assigned unique sample 

numbers, and stored frozen until sample preparation. Raw agricultural commodity (RAC) 

samples were processed for analysis by chopping with dry ice. The chopped samples were 

stored frozen (generally -20°C) until extraction and analysis. 

B.3. Analytical Methodology 

The method used for sample analysis was derived from Determinalion of Residues of 

Methoxyfenozide in High Moisture Crops by Liquid Chromatography with Tandem Mass 

Spectrometry Detection, S.L. Byrne and M.J. Hastings, Dow AgroSciences method GRM: 02.25, 

dated 4 October 2002; and Rohm and Haas Report #34-98-87, titled Tolerance Enforcement 

Method.for Parent RH-2485 in Pome Fruit. 

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Crop Field Trial/Residue Decline - Chives (Leaves) 

Residues of mcthoxyfenozide were extracted from chives by homogenization with 90% 

methanol/I 0% 0.1 N HCI, then shaken and centrifuged. The extract was purified by solid phase 

extraction (SPE) using an Evolute ABN SPE cartridge. Samples were analyzed by Liquid 

Chromatography with Tandem Mass Spectrometry Detection (LC/MS/MS). Based on recoveries 

from samples fortified at the LLMV, the LOO and LOQ for fresh leaves were 0.0016 ppm and 

0.0048 ppm, and for dried leaves were 0.0146 and 0.0438 ppm, respectively. Analytical sets 

typically consisted of calibration standards, unfortified controls, fortified controls, and treated 

samples. 

C. RESULTS AND DISCUSSION 

Control samples were fortified and analyzed both prior to, and concurrently with, the 

field trial samples. Method validation recoveries of methoxyfenozide from samples of fresh 

chives fortified at 0.0 I 0 ppm to 10 ppm ranged from 83-91 % (86 ± 2. 7%. n = 9). Concurrent 

recoveries from samples of fresh chives fortified ·with methoxyfenozide at 0.010 ppm to 20 ppm 

were in the range from 84-98% (92 ± 5.8%, n = 7). Method validation recoveries of 

methoxyfenozide from samples of dried chives fortified at 0.050 ppm to 50 ppm ranged from 85-

89% (87 ± 1.5%, n = 9). Concunent recoveri es from dried chives fortified at 0.050 ppm to 200 

ppm ranged from 81-106% (92 ± 11 %, n= 7). 

Method validation and concurrent recovery results are summarized in Table C.1, below. 

Methoxyfenozide residues in control samples of fresh and dried chives were <0.010 ppm and 

<0.050 ppm, respective ly. A five-point standard curve was generated by injecting constant 

volumes of standard solutions each time an analytical set was run. The correlation coefficient 

was always reported to be 2:0.999. 

TABLE C.1 Summary of Recoveries of Methoxyfenozide from C hives (Leaves) 

Matrix Analyte S r>ike level Sample size Type of Recoveries Mean ± std.dcv. 

(r>pm) (n) Recover y (%) (%)4 

MV1 91. 88. 88 89 ± 2 

0.010 6 

CR: 97.97. 98 97 ± I 

Chives 0.30 3 MV 85.84. 84 84 ± I 

(Fresh Methoxyfcnozidc 2.0 3 SSCR3 89.93. 92 91 ± 2 

Leaves) MV 84. 83.84 84 ± I 

10 4 

CR 91 9 1 

20 3 CR 88. 84. 86 86 ± 2 

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TABLE C.I 

Methoxyfenozide/62719-442/PC Code 121027/Dow AgroSciences/62719 

DACO 7.4.1 /0PPTS 860.1500/0ECD llA 6.3.1, 6.3.2, 6.3.3 and lllA 8.3.1 , 8.3.2, 8.3.3 

Crop Field Trial/Residue Decline - Chives (Leaves) 

Summary of Recoveries of Methoxyfenozide from Chives (Leaves) 

Matrix Ana lyte Spike level Sample size Type of Recoveries Mean ± std.dev. 

(ppm) (n) Recovery (%) (%)4 

Chives MV 87. 88. 89 88 ± I 

(Dried 0.050 6 

Leaves) CR 106, 102. 103 104 ± 2 

MV 86. 85. 85 85 ± I 

2.0 6 

Methoxyfenozidc SSCR 90.88. 88 89 ± 1 

MV 86. 85. 88 86 ± 2 

50 4 

CR 92 92 

200 3 CR 82. 81. 81 8 1 ± I 

I. MV = Method Validation recoveries. 

2. CR = Concurrent Recoveries. 

3. SSCR = Storage Stabi lity Concurrent Recoveries 

4. Standard deviation is not calculated for sample sets with n < 3. 

Chives samples were stored frozen for up to 119 days (fresh leaves) and 122 days (dried 

leaves) after collection. A freezer storage stability study was conducted using samples of chives 

fortified with 2.00 ppm methoxyfenozide, and stored for 110 days (fresh leaves) and 112 days 

(dried leaves). Concurrent recoveries ofmethoxyfenozide during analysis of storage stability 

samples of fresh leaves and dried leaves were in the range 89-93% (91 ± 2%, n = 3) and 88- 90% 

(89 ± l %, n = 3), respectively. Recoveries from stored chives fortified with methoxyfenozide at 

2.00 ppm ranged from 91-93% (92 ± 1.1 %, n = 3) and 86-87% (86 ± 0.6%, n = 3) for fresh and 

dried chives, respectively (see Table C.2, below). 

Following four foliar directed or foliar broadcast applications of Intrepid 2F to chives 

plants at a total seasonal rate of approximately 1.0 lb ai/ A at 8 to 11-day RTis, and a 1-day PHI, 

the maximum methoxyfenozide residues were 13 ppm in fresh leaves, and 118 ppm in dried 

leaves (field trial 07240.12-CA * 17). No detectable residues were found in control samples. 

The residue trials were not adversely impacted by the fanning practices or environmental 

conditions of the trials. Crops were grown and maintained according to typical agricultural 

practices for each geographical region. Irrigation was used to supplement moisture available 

from precipitation, as needed. The selected sites provided an appropriate range of soil types, and 

the crop varieties selected were typical for commercial production in each area. Weather 

conditions at the field sites were generally considered nonnal, and no anomalous events were 

recorded. The residue results are presented in Tables C.3 and C.4, below. 

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Crop Fie ld Trial/Residue Decline - Chives (Leaves) 

TABLE C.2 Summary o f Storage Conditions. 

Matrix (RAC Analyte Storage Temr>. Actual Storage Interval of Demonstrated Storage Stability 

or Extract) ("C) Duration (Days) Storage Stability (Days) Recoveries (%) 

Chives Methoxyfcnozidc <-20°C 119 I IO 9 I. 9 I. 93 

(Fresh Leaves) 

Chives Methoxyfcnozide <-20°C (Dried Leaves) 

122 I 12 86.86.87 

TABLE C.3 Residue Data from C hive Field Trials w ith Methoxyfenozide. 

EPA Trial 10/(City, Commodity Growing Crop/Variety Total Rate PHI Mcthoxyfenozide 

State)Near Region or Matrix (lbs ai/A) (days) (ppm) 

07240. 12-CA*I7/ Fresh I.caves 1.0 I 13. 12 

alinas. CN20 12 IO Chives/Purly Dried Leaves 1.0 I I 12. I 18 

07240. 12-CA* 18/ Fresh Leaves 1.0 I 6.6. 6.8 

alinas. CN 2012 10 Chives/Staro 

Dried Leaves 1.0 I 63. 65 

07240.12-MD04/ Fresh Leaves 1.0 I 7.4. 5.7 

Salisbury. MD/2012 2 Chives/Fancy Dried Leaves 1.0 I 13. 12 

TABLE C.4 Summary of Mcthoxyfenozide Residue Data from C hive Field Trials. 

Total Use Pill Resid ue Levels (ppm) 

Commod ity Analyte Rate (days) (lbs ai/A) n Min. Max. HAF'P Median Mean Std. Dev. 

Chives Mcthoxyfcn ozide (Fresh Leaves) 1.0 I 6 5.7 13 12.5 7.1 8.6 3.1 

Chives Methoxyfcnozide 1.0 I 6 12 11 8 11 5 64 64 46 (Dried Leaves) 

• I IAFT = I l1ghes1 Average 1'1cld Trial. 

D. CONCLUSION 

The study was conducted consistent with standard agricultural practices as per proposed 

experimental designs. The number and geographical distribution of the supervised crop field 

trials on chives are adequate. Weather conditions at the field sites were generally considered 

normal and no anomalous events were recorded. 

The LC/MS/MS method used for determining methoxyfenozide residues in chives 

(leaves) was adequate for data collection. Following four foliar applications at a targeted rate of 

0.25 lb ai/A per applicatio n. for a total seasonal use rate of approximately 1.0 lb ai/A. and a 

I -day PHI, maximum mcthoxyfenozide residues were 13 ppm in fresh chi ves (leaves), and 118 

ppm in dried chives (leaves). An adjuvant was included in each tank mix at all trial sites. The 

submitted storage stability data indicated that the residues were stable under the conditions at 

which samples were held between sampling and analysis. 

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Crop Field Trial/Residue Decline - Ch ives (Leaves) 

E. REFERENCES 

l) D231303; H. Podall; 19 May 1997. 

2) European Commission, Health & Consumer Protection Directorate General; Revie"v11 

Reportfor the active ingredient Methoxyfenozide; 7 October 2004. 

F. DOCUMENT TRACKING 

Petition Number: 4£8298 

DP Barcode: D425285 

PC Code: 121027 

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