UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

OFFICE OF
CHEMICAL SAFETY AND

POLLUTION PREVENTION MEMORANDUM

Date: 11/15/11

SUBJECT: Penflufen. Human Health Risk Assessment to Support New Uses on Potato (Crop Subgroup 1C), Legume Vegetabl es (Crop Group 6 and Crop Group 7), Cereal Grains (Crop Group 15 and Cr op Group 16), Oilseeds (Crop Group 20),

and Alfalfa.

PC Code: 100249 DP Barcode: D387450

Decision No.: 431556 Registration No.: 264-RRRI, 264- RRRO, 264-RREN, 264-RREL, 264-RREU, 264-RRER, 263-RREE, 264-

RREG

Petition No.: PP# 0F7711 Regulatory Action: New Active Ingredient; Section 3 Registration Risk Assessment Type: Single Chemical Aggregate Case No.: NA

TXR No.: NA CAS No.: 494793-67-8

MRID No.: NA 40 CFR: TBD

FROM: Donna S. Davis, Chemist Alexandra LaMay, Biologist Linda Taylor, Toxicologist

Risk Assessment Branch VII Health Effects Division (7509P)

THROUGH: Christine L. Olinger, Senior Chemist, RAB VII Michael S. Metzger, Chief, RAB V & VII Steven Knizner/Ray Kent , RARC Designated Reviewers Health Effects Division (7509P)

TO: Marianne Lewis, Risk Manager Venus Eagle, Product Manager 01 Meredith Laws, Chief

Insecticide-Rodenticide Branch Registration Division (7505P)

Attached please find the human health risk asse ssment for the new Bayer CropScience fungicide, penflufen. This assessment addresses in-furro w and seed treatment use on potatoes and seed treatment use on legume vegetables, cereal grains, oilseeds, and alfalfa for the active ingredient, penflufen only, with one exception. In review ing end use product la bels, rotational crop language recommendations are based on consideration of al l active ingredients in the

formulation. All other human health risk asse ssment considerations for co-formulants will be addressed in separate residue chemistr y summary documents as appropriate.

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Table of Contents
1.0 Executive Summary ......................................................................................................... .... 4

2.0 HED Recommendations....................................................................................................... 6

2.1 Data Deficiencies/Conditi ons of Registration .................................................................. 6

2.2 Tolerance Considerations ................................................................................................. 6 2.2.1 Enforcement Analytical Method ............................................................................... 6

2.2.2 International Harmonization ..................................................................................... 7

2.2.3 Recommended Tolerances ........................................................................................ 7

2.2.4 Revisions to Petitione d-For Tolerances .................................................................... 8

2.3 Label Recommendations .................................................................................................. 8

2.3.1 Recommendations from Residue Reviews ............................................................... 8
2.3.2 Recommendations from Occupational Assessment ................................................ 10

3.0 Introduction .............................................................................................................. .......... 10 3.1 Chemical Identity ......................................................................................................... .. 10 3.2 Physical/Chemical Characteristics ................................................................................. 11

3.3 Pesticide Use Pattern ..................................................................................................... . 11 3.4 Anticipated Exposure Pathways ..................................................................................... 13

3.5 Consideration of Environmental Justice ........................................................................ 13

4.0 Hazard Characterization and Dose-Response Assessment ................................................ 14 4.1 Toxicology Studies Available for Analysis ................................................................... 14 4.2 Absorption, Distribution, Metabo lism, & Elimination (ADME) ................................... 14 4.2.1 Dermal Absorption ..................................................................................................... 1 5 4.3 Toxicological Effects ..................................................................................................... 15 4.4 Safety factor for Infants and Children (FQPA Safety Factor) ....................................... 16 4.4.1 Completeness of the Toxicology Database ................................................................ 16 4.4.2 Evidence of Neurotoxicity .......................................................................................... 16 4.4.3 Evidence of Sensitivity/Susceptibility in the Developing or Young Animal ............. 17 4.4.4 Residual Uncertainty in the Exposure Database ......................................................... 17 4.5 Toxicity Endpoint and Point of Departure Selections .................................................... 18 4.5.1 Dose-Response Assessment ....................................................................................... 18 4.5.2 Recommendation for Combining Routes of Exposures for Risk Assessment ........... 19

4.5.3 Cancer Classification and Risk Assessment Recommendation .................................. 20 4.5.4 Summary of Points of Departure and Toxicity Endpoints Used in Human Risk

Assessment .................................................................................................................... ............ 20

5.0 Dietary Exposure and Risk Assessment ............................................................................ 22 5.1 Metabolite/Degradate Residue Profile ........................................................................... 22 5.1.1 Summary of Plant and Live stock Metabolism Studies ........................................... 22
5.1.2 Summary of Environmental Degradation ............................................................... 23
5.1.3 Comparison of Metabolic Pathways ....................................................................... 24
5.1.4 Residues of Concern Summary and Rationale ........................................................ 24

5.2 Food Residue Profile ...................................................................................................... 26

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5.3 Water Residue Profile .................................................................................................... 27 5.4 Dietary Risk Assessment ................................................................................................ 27 5.4.1 Description of Residue Data Used in Dietary Assessment ..................................... 27
5.4.2 Percent Crop Treated Used in Dietary Assessment ................................................ 28
5.4.3 Acute Dietary Risk Assessment .............................................................................. 28
5.4.4 Chronic Dietary Risk Assessment .......................................................................... 28
5.4.5 Cancer Dietary Risk Assessment ............................................................................ 28
5.4.6 Summary Table ....................................................................................................... 28

6.0 Residential (Non-Occupational) E xposure/Risk Characterization .................................... 29 6.1 Spray Drift ............................................................................................................... ....... 29

7.0 Aggregate Exposure/Risk Characterization ....................................................................... 29

8.0 Cumulative Exposure/Risk Characterization ..................................................................... 30

9.0 Occupational Exposure/Risk Characterization .................................................................. 30

9.1 Short-/Intermediate-Te rm Handler Risk ........................................................................ 30

9.2 Short-/Intermediate-Term Post-Application Risk .......................................................... 34 9.2.1 Dermal Postapplication Risk................................................................................... 34
9.2.2 Inhalation Postapplication Risk .............................................................................. 36

10.0 References ............................................................................................................... ........... 36

Appendix A. Toxicology Prof ile and Executive Summaries ....................................................... 38 A.1 Toxicology Data Requirements ...................................................................................... 38 A.2 Toxicity Profiles ......................................................................................................... .... 39

A.3 Hazard Identification an d Endpoint Selection ............................................................... 49

A.4 Executive Summaries ..................................................................................................... 6 4

Appendix B. Metabolism Data ................................................................................................... .. 92 B1. Structures and Identify of Metabolites of Penflufen ......................................................... 92 B2. Plant Metabolism Study Summaries ................................................................................. 99

B3. Livestock Metabolism Studies ........................................................................................ 101

Appendix C. Physical/Chemical Properties ............................................................................... 103

Appendix D. End Use Products and Detailed Label Restrictions .............................................. 104

Appendix E. Review of Human Research ................................................................................. 106

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1.0 Executive Summary

Penflufen is a new carboxamide fungicide proposed for use primarily as a seed treatment in alfalfa, potatoes (tuberous and corm crop subgr oup 1C), legume vegetables including soybeans (crop group 6 and crop group 7), ce real grains (crop group 15 and crop group 16), and oilseeds (crop group 20). An in-furrow appl ication to potatoes is also pr oposed. The reported pesticidal

mode of action is as an i nhibitor of mitochondrial respir ation by inhibiting succinate dehyrogenase, an enzyme in the electron trans port system. Bayer CropScience has requested registration of the uses listed a bove and the establishment of to lerances to support those uses. Penflufen is being reviewed as part of a globa l work-sharing project with Australia (APVMA) and Canada (PMRA).

The toxicology database is consid ered complete for penflufen. The liver and thyroid are target organs for penflufen. Additionally, increased incidence of thyroid follicular cell hypertrophy/hyperplasia was observe d across studies and species. Reproductive toxicity was observed in the 2-generation reproduction study in rats. Delayed sexual maturation was observed in females in both generations, and th e magnitude of the associated decline in body weight was not considered a fact or in the delay in sexual maturation. Developmental toxicity

was not observed in the rat or ra bbit, although the dose le vels in both studies were not considered adequate to assess developmental toxicity potential of penflufen. However, there is little concern that new studies would identify a developm ental endpoint with a NOAEL lower than the

NOAEL selected for risk assessment. Decreased motor/locomotor activity was observed in both sexes of rats following acute and in female rats following subchronic oral exposure, although neuropathological lesions were not observed in either study. Ther e are no mutagenicity concerns for penflufen. The animal data on penflufen ar e suggestive of carcinogeni city, which raises a concern for carcinogenic effects but are judged not sufficient for qua ntification of cancer risk in

humans.

For the acute dietary risk assessment, an acute reference dose (aRfD) of 0.50 mg/kg/day was selected for assessment of all populations, base d on a NOAEL of 50 mg/kg/ day in the rat acute neurotoxicity study with decrea sed motor and locomotor activities in females observed at 100 mg/kg/day. Since the FQPA 10X fa ctor is being reduced to 1X (see discussion below), the acute population adjusted dose (aPAD) is equal to the aR fD. For the chronic diet ary risk assessment, a chronic reference dose (cRfD) of 0.32 mg/kg/day was select ed for assessments of all populations, based on a NOAEL of 38 mg/kg/day from the chronic dog study. The LOAEL of 357 mg/kg/day is based on decreased terminal body weight and body wei ght gain (females), increased prothrombin time (males), increa sed alkaline phosphate activity (both sexes), decreased cholesterol (both sexe s), increased GGT levels (both sexes), decreased albumin and albumin/globulin ratio (both sexes), decreased calcium and phosphorus (both sexes), increased liver weights (both sexes), increased inciden ce of focal hepatocellular brown pigment and hepatocellular hypertrophy (both se xes), increased incidence of z ona glomerulosa vacuolation of the adrenal gland (females), and an increased incidence of thyroid follicular cell hypertrophy (both sexes). No dermal hazard was identified for penflufen. Since the FQPA 10X factor is being reduced to 1X, the chronic PAD is equa l to the cRfD. For short-term occupational exposure scenarios involving inhalation exposur e, the NOAEL of 55.7 mg/kg/day was selected from the dog oral subchronic toxicity study. The LOAEL of 532 mg/kg/day was based on

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decreased body weight/body weight gain in female s, increased alkaline p hosphatase activity in both sexes, increased GGT activit y in both sexes, decreased albumin in males, increased liver weights in both sexes, increased adrenal weights in males, increas ed incidence of hepatocellular hypertrophy in both sexes, and an increased incidence of slight diffuse cortical hypertrophy/hyperplasia in the adrenal in male s. For the intermediate-term occupational exposure scenarios involving inhalation exposur e, the NOAEL of 38 mg/kg/day was selected from the chronic dog oral toxicity study disc ussed above. Penflufen has been classed as “suggestive” with respect to carcinogenicity and the Agency has determined that the chronic population adjusted dose is protective of a ll long-term effects, including potential carcinogenicity.

The risk assessments conducted for penflufen were based on the most sensitive endpoints in the toxicity database, and the NOAELs selected for risk assessment are cons idered protective of potential developmental, neurotoxic, and immunot oxic effects for infants and children. Further, highly conservative exposure estimates were inco rporated into the risk assessment; therefore, reduction of the 10X FQPA safety factor to 1X is considered appropriate.

The residue chemistry database is considered co mplete for penflufen. The nature and magnitude of the residue in plants has been adequately de lineated. The nature and magnitude of residues in rotational crops has also been adequately delineated and re sidues are not expected in commodities planted in the same fields no less than 30 days after treated seeds have been planted. The residue of concer n in plants and rotational crop s is the parent compound only. Residues in livestock commodities are not expected since quantifiable residues are not likely in any livestock feedstuff. Adequate storage stability, method validation data and processing studies have been submitted. An adequate LC/MS/MS (liquid chromatography/tandem mass spectrometry) analytical method is available to enforce the proposed tolerances. There are no issues with respect to international harmonization raised by this action.

Environmentally, penflufen is a moderately mobile ch emical that is expected to be persistent in

the environment in aerobic and anaerobic conditions. Based on the environmental fate parameters, there is the potential for penflufen to reach water resources. As this is a new chemical, there is no monitoring data available, thus drinking water concentrations were estimated using models.

Highly conservative acute and ch ronic dietary (food and water) asse ssments using tolerance level residues, assuming 100% crop treated and inco rporating modeled water exposure estimates

demonstrated that estimated risks were <1% of the acute population adjusted dose (aPAD) at the

95 th percentile exposure and <1% of the chronic population adjusted dose (cPAD) for the U.S. population and all modeled populations. There are no residential uses for penflufen; therefore, the aggregate risk estimate for this chemical is equivalent to the dietary risk estimate and there are no concerns for acute or chronic aggr egate risk estimates for penflufen.

No dermal hazard has been identified for pe nflufen; therefore o ccupational handler and postapplication risks were assessed for the inha lation route of exposure only. All estimated

short- and intermediate-term handler inhalation risks greatly exceeded th e Agency’s level of

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concern. Postapplication inhalation exposure is expected to be ne gligible; therefore a quantitative assessment was not required.

This risk assessment relies in part on data from studies in which adult human subjects were intentionally exposed to a pest icide or other chemical. Thes e studies, which comprise the Pesticide Handlers Exposure Database (PHED), the Agricultural Handler Exposure Task Force (AHETF), the Outdoor Residential Exposure Task Force (ORETF), and Seed Treatment SOPs and study MRID 47054702 have been determined to require a review of their ethical conduct, have received that review, and have been determined to be ethical.

2.0 HED Recommendations

2.1 Data Deficiencies/Conditions of Registration

Provided the end use product labels are revise d as noted in Section 2.3.1, below, there are no data gaps with respect to t oxicology, residue chemistry or oc cupational exposure assessment for penflufen.

2.2 Tolerance Considerations

2.2.1 Enforcement Analytical Method

An adequate analytical method is available to enforce the propos ed tolerances for penflufen in plant commodities. The LC/MS/MS method, EL- 002-P09-03, has been adequately validated, has undergone a successful ILV (independent labora tory validation), is considered adequately radiovalidated and has been reviewed by the Ag ency for appropriateness as an enforcement

method.

Bayer method EL-002-P09-03 is described briefl y as follows. Samples are homogenized and extracted with 4:1 acetonitrile (ACN)/water repe atedly. The extracts are combined, cleaned up using solid phase extraction; a stab le, isotopically labeled internal standard is added, and taken to dryness. Hydrochloric acid is a dded to the dried extract and the solution is heated to hydrolyze any conjugates. The sample is then neutralized with sodium hydr oxide and diluted with formic acid in water. An aliquot of the extract is an alyzed for residues of penflufen by LC/MS/MS.

Penflufen has also been subjected to analys is by the FDA multi-residue method protocols. Penflufen is not recovered by the FDA multi-residue methods.

BayerCrop Science provided a stable, isotopical ly labeled reference standard for the parent compound, penflufen to the EPA National Standa rd Repository (email communication from T. Cole to D. Davis 11/15/11).

Page 6 of 106Penflufen Human Health Risk Assessment D387450

2.2.2 International Harmonization

Penflufen is part of a global review project with Canada and Australia. During the course of the review, the Agencies reached agreement on both the tolerance expression for plant commodities

and the tolerance levels for commodities common to the three countries. At this time no tolerances are required in the U.S. for livestock commodities; therefore, a discussion of international harmonization with respect to liv estock commodities is not germane to this

assessment.

There are no Codex or Mexican MRLs for penflufe n and U.S. and Canadian tolerances are fully harmonized; therefore, there are no issues with re spect to international harmonization associated

with the tolerances reco mmended in this action.

2.2.3 Recommended Tolerances

Table 2.2.3 summarizes the registra nt’s proposed tolerances and the Agency’s final tolerance recommendations. The tolerance expressi on for penflufen should read as follows:

Tolerances are established for residues of the fungicide penflufen, including its metabolites and degradates, in or on the comm odities in the table below. Compliance with the tolerance levels for the penflufe n is to be determined by measuring only penflufen ( N -[2-(1,3-dimethylbutyl)phe nyl]-5-fluoro-1,3-dimethyl-1 H -pyrazole-4- carboxamide).

Table 2.2.3. Toleranc e Summary for Penflufen Commodity Proposed Tolerance (ppm) Recommended Tolerance (ppm) Comments Correct Commodity Definition Alfalfa, Forage 0.01 0.01 Alfalfa, forage Alfalfa, Hay 0.01 0.01 Alfalfa, hay

Tuberous and CormVegetable (Crop Subgroup 1C) 0.01 0.01 Vegetable, tuberous and corm, subgroup 1C

Legume Vegetables, succulent or dried (Crop Group 6) 0.01 0.01 Vegetable, legume, group 6

Foliage of Legume Vegetables, including soybeans (Crop Group 7) 0.01 0.01 Vegetable, foliage of legume, group 7

Soybean, seed 0.01

- Not required, soybean seed is included in crop group 6. Cereal grains (Crop Group 15) 0.01 0.01 Grain, cereal, group 15

Forage, fodder and straw of Cereal grains (Crop Group 16) 0.01 0.01 Grain, cereal, forage, fodder and straw, group 16

Oilseeds (Crop Group 20) 0.01 0.01 Oilseed, group 20

Cotton, gin by-products 0.01 0.01 Cotton, gin by-products

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2.2.4 Revisions to Petitioned-For Tolerances

The Agency is recommending that tolerances be set for the commodities requested by the registrant at the levels requested. However, mi nor modifications to some commodity definitions are recommended to be consistent with Agen cy naming-conventions for commodities.

2.3 Label Recommendations

2.3.1 Recommendations from Residue Reviews

HED is aware of the issue regarding the use of treated seeds (primarily corn) being used for ethanol production and the potenti al of pesticide residues occurri ng in the byproducts that can be

used for livestock feed or fertilizer. The standa rd restriction with word ing such as that on the proposed penflufen labels ("Do not use for fee d, food or oil purposes") is not adequate to preclude this use of treated seeds. Since OPP is actively working with Bayer to develop a more appropriate label statement to address this concern, HED recommends that the wording to be developed through this process be used on the labels of all th e penflufen products.

Additional label-specific revisions are as follo ws. Note that the suggested rotational crop language includes consideration of rotational crop restrictions fo r penflufen as well as any coformulant(s) in the end-use product.

PENPROME 177FS (264-RREE)

• The “rate per seed” for soybeans needs to be co rrected to reflect the appropriate rate and AOSA (Association of Official Seed Analysts) recommendation of 4000 soybean seeds per pound.

• The crop rotation restriction s hould be revised to specify the following. “Crops for which there are registered use of penflufen, which includes al falfa, potatoes (Crop Subgroup 1C), legume vegetables (Crop Group 6/7), cereal grains (Cro p Group 15/16), and oil seeds (Crop Group 20) may be replanted at any time. All other crops may be planted no less than 30 days after planting treated seeds.”

PEN 240FS (264-RRRO)

• The rate per seed for soybeans, cotton and fi eld corn should be corrected to reflect the AOSA recommendation of 4000 seeds per pound for soybean, 3600 seeds per pound for cotton and 1360 seeds per pound for field corn.

• Under the potato instructions for in-furrow treatment in combination with seed piece treatment the application rate column in the table should be revised to read as follows. “Apply a minimum of 0.4 fl oz per 1,000 ro w feet (4 ml per 100 row meters) up to a maximum in-furrow application of 9.2 fl oz per acre.”

• The crop rotation restriction s hould be revised to specify the following. “Crops for which there are registered use of penflufen, which includes al falfa, potatoes (Crop Subgroup 1C), legume vegetables (Crop Group 6/7), cereal grains (Cro p Group 15/16), and oil seeds (Crop Group 20) may be replanted at any time. All other crops may be planted no less than 30 days after planting treated seeds.”

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PENPRO 118FS (264-RREG)

• The crop rotation restriction s hould be revised to specify the following. “Crops for which there are registered use of penflufen, which includes al falfa, potatoes (Crop Subgroup 1C), legume vegetables (Crop Group 6/7), cereal grains (Cro p Group 15/16), and oil seeds (Crop Group 20) may be replanted at any time. All other crops may be planted no less than 30 days after planting treated seeds.” PENCLO 273.5FS (264-RREL)

• The crop rotation restriction s hould be revised to specify the following. “Crops for which there are registered uses of both clothian idin and penflufen, which includes canola, cotton, cereal grains except rice, mustard seed, potato (Crop Subgroup 1C) and soybeans may be replanted at any time. Grasses, non- grass livestock feeds, dried beans and dried peas may be planted no less than 30 days afte r planting treated seeds. Do not plant any other crop in the treated area for at least tw elve months after treat ed seeds are planted.
”

PENRED 240FS (264-RREN)

• The rate per seed for soybeans, cotton and fi eld corn should be corrected to reflect the AOSA recommendation of 4000 seeds per pound for soybean, 3600 seeds per pound for cotton and 1360 seeds per pound for field corn.

• Under the potato instructions for in-furrow treatment in combination with seed piece treatment the application rate column in the table should be revised to read as follows. “Apply a minimum of 0.4 fl oz per 1,000 ro w feet (4 ml per 100 row meters) up to a maximum in-furrow application of 9.2 fl oz per acre.”

• The crop rotation restriction s hould be revised to specify the following. “Crops for which there are registered use of penflufen, which includes al falfa, potatoes (Crop Subgroup 1C), legume vegetables (Crop Group 6/7), cereal grains (Cro p Group 15/16), and oil seeds (Crop Group 20) may be replanted at any time. All other crops may be planted no less than 30 days after planting treated seeds.”

PENCLOTRIME 310.68FS

• The crop rotation restriction s hould be revised to specify th e following. “Areas planted with treated seed may be replanted immediat ely with canola, cott on, corn (field, pop and sweet), cereal grains except rice, must ard, rapeseed, sorghum, soybean, and potatoes (tuberous and corm subgroup 1C). These ar eas may also be replanted no less than 30 days after planting treated seeds with grasse s, non-grass livestock feeds, dried beans, fruiting vegetables (including cucurbits), leaf y vegetables (includi ng brassica vegetables) and sugar beets. Do not plant any other crop in the treated area for at least twelve months after treated seeds are planted.

PENTRI 308FS

• The rate per seed for soybeans needs to be co rrected to reflect the appropriate rate and AOSA recommendation of 4000 soybean seeds per pound.

• The rate per 100 lbs of seed and rate per s eed for field corn should reflect the same application rate. Further, the AOSA reco mmendation of 1260 seeds per pound for field corn should be incorporated into the rate per seed calculation.

• The rate per 100 lbs of seed and rate per seed for cotton should reflect the same application rate. Further, the seeds per pound on the label should be revised to reflect

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3600 cotton seeds per pound.

• The crop rotation restriction s hould be revised to specify the following. “Crops for which there are registered uses of both trifloxystrobin and penflufen, which includes barley, corn, oats, potato, rice, soybean and wheat ma y be replanted at any time. All other crops may be planted no less than 30 days after planting treated seeds.”

2.3.2 Recommendations from Occupational Assessment

The following label revisions are recommended based on the occupati onal assessment. Note that the suggested revisions include consideration of restrictions for penflufen as well as any coformulant(s) in the end-use product.

PENRED 240FS, PEN240FS, PENCLO 273.5FS, PENTRI 308FS, PENPRO 118FS The labeling should state: Bags containing treated seeds shall be labeled with the following information: “After the seeds have been plante d, do not enter or allow wo rker entry into treated areas during the restricted-entry interval (R EI) of 12 hours. Exception: Once the seeds are planted in soil or other planting media, the Worker Protection Standard allows workers to enter

the treated area without restriction if there will be no worker contact with the treated seeds in the soil or planting media.”

PENPROME 177FS The labeling should state: Bags containing treated seeds shall be labeled with the following information: “After the seeds have been plante d, do not enter or allow wo rker entry into treated areas during the restricted-entry interval (R EI) of 24 hours. Exception: Once the seeds are planted in soil or other planting media, the Worker Protection Standard allows workers to enter

the treated area without restriction if there will be no worker contact with the treated seeds in the soil or planting media.”

3.0 Introduction

3.1 Chemical Identity

The structure and chemical identify for penflufen are shown in Table 3.1. The structures for all

metabolites discussed in this risk as sessment are shown in Appendix B.

Table 3.1 Test Compound Nomenclature

Chemical Structure

N H N

N O

F CH

3

CH 3

CH 3 CH 3 CH

3

Empirical Formula C 18 H 24 FN 3 O

Common Name Penflufen

Company experimental name BYF 14182

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Table 3.1 Test Compound Nomenclature

IUPAC name N-[2-(1,3-dimethylbutyl)phenyl]-5-fluoro-1,3-dimethyl-1 H -pyrazole-4-

carboxamide

CAS Name 1 H -Pyrazole-4-carboxamide, N-[2-(1,3-dimethylbutyl)phenyl]-5-fluoro-1,3-dimethylCAS Registry Number 494793-67-8

End-use product/EP PEN 240FS, PENRED 24 0FS, PENCLO 273.5FS), PENTRI 308FS), PENCLOTRIME 310.68FS, PENPROME 177FS

Chemical Class Carboxamide

Known Impurities of Concern None

3.2 Physical/Chemical Characteristics

The physical and chemical properties, as well as a summary of relevant environmental fate parameters are detailed in Appendix C.

Penflufen has a low vapor pressure (10 -9 torr) and is; theref ore, not a volatile pesticide. This active ingredient has an octanol water partition coefficient that would suggest it might have a slight bioaccumulation potential in lipophilic matr ices. Penflufen has low water solubility and does not dissociate; however, environmentally, penflu fen is a moderately mobile chemical that is expected to be persistent in the environment in aerobic and anaerobic conditions. Based on the environmental fate parameters, there is the poten tial for penflufen to reach water resources.

3.3 Pesticide Use Pattern

The proposed use pattern for penflufen on the vari ous crops for which registration is sought are

summarized in Table 3.3.

Table 3. 3. Summary of Dir ections for Use of Penflufen

Application Timing, Type,

and Equipment Formulation Use Rates PHI (days) Use Directions and

Limitations

Alfalfa

Slurry or misttype seed

treatment PENRED 240FS

PENTRI 308FS

PENPROME

177FS

PEN 240FS 0.015 lb ai/100 lbs seed (15 g ai/100 kg seed) NS Do not use for feed, food or oil purposes. Store away from feeds

and foodstuffs.

Rotational crop

restrictions as detailed in Appendix D.

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Table 3. 3. Summary of Dir ections for Use of Penflufen

Application Timing, Type,

and PHI Use Directions and Equipment Formulation Use Rates (days) Limitations Potato (Tuberous and Corm Crop Subgroup 1C)

Apply as a dilute spray to seed pieces PENRED 240FS

PENCLO 273.5FS

PENPRO 118FS

PEN 240FS 0.002 lb ai/100 lbs seed (2 g ai/100kg seed)

may be combined with in-furrow application on PENRED 240FS and

PEN 240 FS labels NS Do not use for feed, food or oil purposes. Store away from feeds

and foodstuffs.

Rotational crop

restrictions as detailed in Appendix D.

Ground application as

in-furrow

spray PENRED 240FS

PEN 240 FS 0.12 lb ai/A

may be combined with seed piece treatment application NS Do not use for feed, food or oil purposes. Store away from feeds

and foodstuffs.

Rotational crop

restrictions as detailed in Appendix D. Legume Vegetables Including Soybean (Crop Group 6C)

Slurry or misttype seed

treatment PENRED 240FS

PENTRI 308FS

PENPROME 118 FS (dried only)

PEN 240 FS 0.005 lbs ai/100 lbs seed (5 g ai/100 kg seed) NS Do not use for feed, food or oil purposes. Store away from feeds

and foodstuffs.

Rotational crop

restrictions as detailed in Appendix D. Cereal Grains (Crop Group 15)

Slurry or misttype seed

treatment PENRED 240FS

PENTRI 308FS (wheat, corn, rice only)

PENPRO 118FS (wheat only)

PENPROME

177FS (barley, wheat,

triticale and rice only)

PEN 240FS Cereal grains, except corn, and sorghum

0.005 lbs ai/100 lbs seed

(5 g ai/100 kg seed)

Corn, sorghum 0.010 lbs ai/100 lbs

seed (10 g ai/100 kg/seed) NS Do not use for feed, food or oil purposes. Store away from feeds

and foodstuffs.

Rotational crop

restrictions as detailed in Appendix D.

Oilseeds (Crop Group 20)

Slurry or misttype seed

treatment PENRED 240FS

PENTRI 308FS

(cotton only)

PENCLOTRIME 310.68FS (canola, rape, mustard only)

PENCLO 273.5FS (cotton only) PEN 240FS (cotton, 0.015 lb ai/100 lbs seed (15 g ai/100kg seed) NS Do not use for feed, food or oil purposes. Store away from feeds

and foodstuffs.

Rotational crop

restrictions as detailed in Appendix D.

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Table 3. 3. Summary of Dir ections for Use of Penflufen

Application Timing, Type,

and PHI Use Directions and Equipment Formulation Use Rates (days) Limitations sunflower, safflower only)

3.4 Anticipated Exposure Pathways

The Registration Division has requested an assess ment of human health risk to support the proposed new use of penflufen on alfalfa, potatoe s, legume vegetables including soybeans, cereal grains, and oilseeds. Humans may be exposed to penflufen in their diet resulting from residues present in foods grown from penflufen treated s eeds. Further, given the environmental fate parameters of penflufen and the proposed use outdoors in agricultural settings, the potential exists for penflufen to reach wa ter resources resulting in potential residues in drinking water. There are no residential uses of penflufen, so exposure in residential and non-occupational settings is not likely. In an occupational setting, a pplicators may be expo sed while handling the pesticide prior to application, as well as during ap plication. There is also potential for exposure to planters who are handling treated seeds. Th e potential for postapplicat ion exposures following the planting of penflufen-treated seeds is unlikely because sustained levels of contact with treated seed after it has been planted in the soil or other planting media w ould not be expected.

These are the first registrations pr oposed for penflufen; therefore, th is is the first risk assessment prepared by the Agency to address potential risks associated with the use of this new fungicide. This assessment will consider the dietary a nd worker risks aforementioned for all newly proposed uses of penflufen.

3.5 Consideration of Environmental Justice

Potential areas of environmental ju stice concerns, to the extent possi ble, were considered in this human health risk assessment, in accordance w ith U.S. Executive Order 12898, "Federal Actions

to Address Environmental Just ice in Minority Populations an d Low-Income Populations," ( http://www.eh.doe.gov/oepa/ guidance/justice/eo12898.pdf . As a part of every pesticide risk assessment, OPP considers a large variety of consumer subgroups according to well-established procedures. In line with O PP policy, HED estimates risks to population subgroups from pesticide exposures that are ba sed on patterns of that subgrou p’s food and water consumption,

and activities in and around th e home that involve pesticide use in a residential setting. Extensive data on food consumption patterns are compiled by the USDA under the Continuing Survey of Food Intake by Individuals (CSFII) and are used in pesticide risk assessments for all registered food uses of a pesticide. These da ta are analyzed and categorized by subgroups based on age, season of the year, ethnic group, and region of the country. Additi onally, OPP is able to assess dietary exposure to smaller, specia lized subgroups and exposure assessments are performed when conditions or circumstances warrant. Whenever appropriate, non-dietary exposures based on home use of pesticide products and associated risks for adult applicators and for toddlers, youths, and adults en tering or playing on tr eated areas postapplica tion are evaluated. Further considerations are currently in development as OPP has committed resources and

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expertise to the development of specialized soft ware and models that consider exposure to bystanders and farm workers as well as lifesty le and traditional dietary patterns among specific subgroups.

4.0 Hazard Characterization and Dose-Response Assessment

4.1 Toxicology Studies Available for Analysis

Based on the proposed use pattern, all required studies for penflufen have been submitted. The available toxicology database is su fficient for assessing the toxicity and characterizing the hazard of the chemical. The available toxicology studies for penflufen are listed in Table A.1 in Appendix A.

• Acute lethality studies (ora l, dermal, inhalation, primary eye and dermal irritation, and dermal sensitization)

• Subchronic oral toxicity studi es (rat, mouse, and dog)

• Developmental (rat and rabbit) and re productive toxicity (rat) studies

• Dermal toxicity and dermal penetrat ion studies (28-day dermal toxicity, in vivo dermal penetration, comparative in vitro dermal penetration (rat vs human skin)

• Neurotoxicity (acute and s ubchronic) and immunotoxicity studies (rat and mouse)

• Chronic oral toxicity studies (rat, mouse, dog)

• Carcinogenicity studies [rat (c hronic combined) and mouse]

• Metabolism studies (rat)

• Mutagenicity battery (parent and metabolites)

4.2 Absorption, Distribution, Metab olism, & Elimination (ADME)

The absorption, distribution, metabolism and excreti on of penflufen in rats were investigated with both [phenyl-UL- 13 C 6 / 14 C] - and [pyrazole-3- 14 C]-labeled test compounds. The absorption, distribution, metabolism, and excretion of the metabolite penflufen-3-hydroxy-butyl were also investigated.

Absorption : The absorption of the radioactivity from the gastrointestinal tract (GIT) was rapid (within 40 to 90 minutes) and almost complete (94%).

Distribution: The results from the whole body autoradi ography showed that the radioactivity was distributed among all tissues, an d tissue concentrations were in the same order of magnitude irrespective of the positi on of the radiolabel. Highest residues were observed in the blood, liver, and kidney. Generally, concentrations in the tissues/organs were propor tional to the dose.

Elimination : No significant differences in the excreti on pattern of radioactivity were observed between the two positions of radiolabel or between sexes. Mo re than 93% of the administered radioactivity was excreted at st udy termination for both radiolabels. The plasma concentration curves showed a fast elimination phase, and the t 1/2 elim 1 was 20-24 hours. The radioactivity

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concentration in the plasma declined to ≈ 1%- ≈ 3.6% of the maximum value within 72 hours post

dose. Both sexes showed one terminal elimin ation phase at the low dose, whereas a second maximum plasma concentration value was exhibi ted after 48 hours at the high dose, possibly due to enterohepatic circulation.

Metabolism : Penflufen was very extensively metaboliz ed in the rat, and numerous metabolites were identified. Unchanged parent compound was found only in low percentages of the administered radioactivity. Metabolic reactions we re detected in at least 10 different positions of the molecule, and a large number of metabolites were identified. Most of the metabolites were demethylated in the pyrazole ring. Hydroxylatio n was another major metabolic reaction leading to trihydroxy and dihydroxy compounds, with only a minor part of the metabolites hydroxylated in only a single position. Further oxidation of hydroxy groups yielded ketones or carboxylic acids. A prominent hydroxylation reaction occurred in the 3 position of the alkyl side chain, and the single metabolite, penflufen- 3-hydroxy-butyl, was detected in very low amounts. However, many metabolites originating from penflufen- 3-hydroxy-butyl were identified, and this metabolite was considered a key intermediate in the rat metabolism. This assumption was supported by the findings of a separate rat ADME study with penflufen-3-hydroxy-butyl, which showed the same metabolic pa ttern as in the metabolism st udies with the parent compound, demonstrating that the rat is systemically exposed to penflufe n-3-hydroxy-butyl after administration of penflufen.

4.2.1 Dermal Absorption

Dermal absorption is minimal (<1%), based on th e findings from two derm al penetration studies available for penflufen; an in vivo single 8-hour applica tion to rats and an in vitro dermal absorption study (human and rat skin).

4.3 Toxicological Effects

Penflufen is an alkylamide fungicide belonging to the chemical class of carboxamides. The reported pesticidal mode of action is as an in hibitor of mitochondrial respiration by inhibiting succinate dehydrogenase, an enzyme in the electron transport system.

The liver and thyroid are target organs for penflufen. Increased liver weight, alterations in clinical chemistry parameters relevant to effects on the liver, and an incr ease in the incidence of hepatocellular hypertrophy were consistent findi ngs across species and du ration of exposure (28- day, 90-day, and 1- to 2-year exposure periods). The hepatic total cy tochrome P-450 content, and benzoxyresorufin (BROD) and pentoxyresorufin (PROD) enzyme activities, were shown to

be increased in rats of both sexe s following subchronic oral exposure. Additionally, increased incidence of thyroid follicul ar cell hypertrophy/h yperplasia was observed across studies and species (no data provided on t hyroid hormone levels). The li ver and thyroid findings were mostly reversible after a 3-month recovery period in the rat. In the rat and mouse, following 104 week/78 week exposure periods at dose levels up to and/or greater than the limit dose, there was

no increase in the incidence of liver or thyroid tumors.

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Reproductive toxicity was observed in the 2-ge neration reproduction stu dy in rats. Delayed sexual maturation was observed in females in both generations, and magnitude of the associated decline in body weight was not considered to be a factor in the delay in sexual maturation. Developmental toxicity was not observed in the rat or rabbit, although the dose levels in both studies were not considered adequate to assess developmental toxicity potential of penflufen. However, there is little concer n that new studies would identify a developmental endpoint with a

NOAEL lower than the NOAEL selected for risk assessment.

Decreased motor/locomotor activity was observed in both sexes of rats following acute and in female rats following subchronic oral exposure, although neuropathologic al lesions were not observed in either study.

There are no mutagenicity concerns. The animal toxicity data on penflufen are suggestive of carcinogenicity, which raises a co ncern for carcinogenic effects but are judged not sufficient for quantification of cancer risk in humans. The classification is based on the presence of a statistically significant increase in histiocytic sarcomas in male rats, a marginal increase in brain astrocytomas, a fatal tumor, in male rats at the high dose, and ovarian adenomas in female rats at the high dose. There was no evidence of car cinogenicity in male or female mice

4.4 Safety factor for Infants and Children (FQPA Safety Factor)

The Agency recommends that the 10X FQPA safe ty factor for the protection of infants and children, be reduced to 1X. The risk assessm ents conducted for penflufen were based on the most sensitive endpoints in the toxicity database, and the NOAELs selected for risk assessment are considered protective of pot ential developmental, neurotoxic, and immunotoxic effects for infants and children. Highly conservative exposure estimates were incorporated into the risk assessment for penflufen. There ar e no residual uncertainties with re gard to pre- and/or postnatal toxicity or neurotoxicity, and e xposure; therefore, reduction of the 10X FQPA safety factor to 1X is appropriate as described in the following sections.

4.4.1 Completeness of the Toxicology Database

As discussed in Sections 4.1 and 4.4, above, the t oxicology database for penflufen is complete for consideration of estimated risks for all popula tions of concern, particul arly with respect to

studies that address the sensitiv ity of infants and children.

4.4.2 Evidence of Neurotoxicity

In the acute neurotoxicity study in rats for penflufen, clinical signs including urine stain in both sexes, an increased incidence of stiff-legged hind limbs, locomotor in-coordination, decreased activity, and clear lacrimation (p roduction and shedding of tears) in females were observed, and

there was a dose-related decrea se in motor activity and loco motor activity in both sexes. Habituation was not affected at any dose level in either sex. In the FOB, females showed a decrease in body temperature compared to the control. Body weights and body weight gains were comparable among the groups (both sexes). All signs of toxi city resolved by day 7. Brain weight was not affected, and there were no co mpound-related gross or microscopic lesions.

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In the subchronic neurotoxicity study in rats, there were no consistent findings during the FOB (other than body weight eff ects), and no treatment-related neuropathological lesions were

observed in either sex that coul d be attributed to treatment. Motor activity was slightly reduced in females, which is consistent with the findings following acute exposure.

There is no other evidence in the toxicology database on penflufen that demonstrates any potential for penflufen to cause any permanent or long-term peripheral or central nervous system toxicity. The clinical findings observed in th e acute study followed a gavage dose and resolved within 7 days.

4.4.3 Evidence of Sensitivity/Susceptibility in the Developing or Young Animal

In the 2-generation reproduction study in rats, a sli ght decrease in litter size (both generations), decreased pup body weight and pup body-weight gain, delayed vaginal patency (both generations), and decreased brain, spleen, and thymus weights were observed in the offspring at the same dose level where decreased body weight , decreased body weight gain, alterations in food consumption, decreased thymus weight in both genders, and decreased spleen weights in females (both generations) were observed in the adult rat.

In the rat developmental toxicity study, the ma ternal findings at the highest dose tested are considered minimal. Although there was a signifi cant reduction in maternal body weight gain at the high dose, which correlated with a decr ease in food consumption, body weights were comparable to those of the control, and the liver changes are considered adaptive and not

adverse. No adverse effects were observed on th e foetuses. The dose levels tested are not considered adequate for assessing the deve lopmental toxicity potential of penflufen.

In the developmental toxicity st udy in rabbits, the maternal findings at the highest dose tested are considered minimal. Although there was a signifi cant reduction in maternal body weight gain at the high dose, which correlated with a decr ease in food consumption, body weights were comparable to those of the control. No other effects were observed. No adverse effects were observed at the highest dose tested. The dose le vels do not appear adequate for assessing the developmental toxicity potentia l of penflufen in the rabbit.

Although there is some eviden ce of qualitative sensitivity of the young (delayed sexual

maturation and decreased little si ze), the effects are well charact erized, and there is a clear NOAEL. The dose level where offspring effects were identified in the reproduction study is comparable to the high dose used in the rat de velopmental toxicity study where no effects were

identified in either the maternal or fetal ra t. Since minimal/no effects were observed in the developmental toxicity studies fo llowing exposure of the maternal animals to dose levels equal to and greater than those tested in the studies used for risk assessment, there is little concern that new studies would identify a developmental endpoint with a NOAEL lower than the NOAELs

selected for risk assessment.

4.4.4 Residual Uncertainty in the Exposure Database

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There is no residual uncertainty in the exposure da tabase for penflufen with respect to dietary (food and water) exposure.

A complete database with respec t to both the nature and magnitude of residues expected in food has been provided. The dietary food exposure a ssessment is based on tolerance level residues, assumes 100% crop treated for all commodities, and incorporates processing factors as appropriate which results in very high-end estimates of dietary food exposure. Further, highly conservative, modeled drinking estim ates of exposure were include d in the assessments. Actual exposures and risks from penflufen in food and drinking water are likely to be far lower than

estimated in this risk assessment.

4.5 Toxicity Endpoint and Point of Departure Selections

4.5.1 Dose-Response Assessment

A detailed description of the toxi city studies used for selecting t oxicity endpoints and points of departure for various exposure scenarios, as well as a detailed rationale for selection of the toxicity endpoints are pr esented in Appendix A.

For the acute dietary risk assessment, the aP AD of 0.50 mg/kg/day was selected for assessment of all populations, based on a NOAEL of 50 mg/kg/da y in the rat acute ne urotoxicity study with

decreased motor and locomotor act ivities in females observed at 100 mg/kg/day. This endpoint is a single-dose effect and is appropriate for th e populations of concern. Neither the rat nor the rabbit developmental toxicity st udy provides an alternate endpoint since no adverse effects were observed at the highest dose levels tested (300 mg/kg/day and 600 mg/kg/da y) in those studies. The endpoint selected for the acute risk asse ssment is considered protective of potential developmental effects that might occur at higher dose levels.

For the chronic dietary risk assessment, th e cPAD of 0.38 mg/kg/day was selected for assessments of all populations, based on a NOAEL of 38 mg/kg/day from the chronic dog study. The LOAEL of 357 mg/kg/day is based on decr eased terminal body weight and body weight gain (females), increased prothrombin time (mal es), increased alkaline phosphate activity, decreased cholesterol, increased GGT levels, decreased albumin and albumin/globulin ratio, decreased calcium and phosphorus, increased liver weights, increased incidence of focal hepatocellular brown pigment and hepatocellula r hypertrophy, and an in creased incidence of thyroid follicular cell hypertrophy in both sexes and an increa sed incidence of vacuolations of the adrenal glands (females). This study provide d the most sensitive endpoint available and is appropriate for chronic dietary expo sure due to the route (oral) a nd duration (chronic) of dosing. For the repeat dose studies available, the dose spread is large in a ll cases (LOAEL of 250-532 mg/kg/day), and the NOAELs are similar (males : 32-64 mg/kg/day/females: 38-76 mg/kg/day). The chronic dog study provides the only NOAEL th at is lower than the acute NOAEL.

For occupational exposure scenar ios involving dermal exposure, no hazard was identified. This is based on the lack of dermal irritation or syst emic effects at the limit dose (1000 mg/kg/day) in a 28-day dermal toxicity study in rats, and the fa ct that dermal absorption is minimal (<1%). This is a route-specific study that also assesse d all of the endpoints used in the other exposure

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scenarios and durations of exposure (e.g. ne urological endpoints, thyroid and liver histopathology). Additionally, th e endpoints assessed in the matern al animals are also assessed in the dermal studies. No increased susceptibi lity was seen between offspring and adult animals in the developmental toxicity studies in rats and rabbits and in the 2-generation reproduction study in rats. Reproductive toxicity was obser ved in the 2-generation reproduction study, based on delayed sexual maturation in the females in both generations. Given a dermal absorption factor of 1%, which was calculated using data from a rat in vivo study and a human:rat in vitro study (see Appendix A.3. for details), the dermal equivalent dose NOAEL for the delays in sexual maturation would be approximately 5800 mg/kg/day, well above the limit dose for the dermal toxicity study. Therefore, the quantification of dermal risk is not required since no hazard

was identified. For short-term occupational exposure scenario s involving inhalation exposure, the NOAEL of 55.7 mg/kg/day was selected from the dog oral subchronic toxicity st udy. The LOAEL of 532 mg/kg/day was based on decrease d body weight/body weight gain in females, increased alkaline phosphatase activity in both sexe s, increased GGT activ ity in both sexes, decreased albumin in males, increased liver weights in both sexes, increased adrenal weights in males, increased incidence of hepatocellu lar hypertrophy in both sexes, and an increased incidence of slight diffuse cortical hypertrophy/hyperpla sia in the adrenal in males. No inhalation studies are available for penflufen. Although a repeat dose inhalation study is a data requirement, based on the magnitude of the inhalation MOEs and the Toxicity Category IV cl assification for acute inhalation exposure, this requirement can be waiv ed. For all of the repeat oral dose studies considered for this exposure scenario, the dose spread is large in a ll cases (LOAEL of 250-532 mg/kg/day), and the NOAELs are similar (males : 32-64 mg/kg/day; fema les: 38-76 mg/kg/day). The subchronic dog study is appropriate for this duration of exposure. In the rat repeat dose subchronic oral toxicity studi es at dose levels up to the limit dose and NOAELs > 200 mg/kg/day, the effects on the liver are consider ed mostly adaptive. In the dog studies, the duration of the study relativ e to the lifespan of the dog is s hort compared to rat studies, which encompass a greater proportion of the rat’s life ; therefore, it is not known whether the liver effects in the dog studies are adaptive. Although the liver find ings in the dog study at the LOAEL may not be adverse, because the dog st udies encompass a small proportion of the dog’s lifespan, they are considered ap propriate as the basis for the LOAEL. The dog study provides the lowest NOAEL for this duration of exposure.

For the intermediate-term occupational exposur e scenarios involving inhalation exposure, the NOAEL of 38 mg/kg/day was selected from the chronic dog oral toxic ity study. The LOAEL of 357 mg/kg/day was based on decreased terminal body weight and body weight gain (females), increased prothrombin time (males), increased al kaline phosphate activity, decreased cholesterol, increased GGT levels, decreased albumin and albumin/globulin ratio, decreased calcium and phosphorus, increased liver weights, increased incidence of focal hepatocellular brown pigment and hepatocellular hypertrophy, and an increased incidence of thyr oid follicular cell hypertrophy in both sexes, and an increased incidence of vacu olation of the adrenal gland in females. The chronic oral toxicity study in dogs is appropriate for this dura tion of exposure. The selected endpoint is the most sensitive endpoint in the data base.

4.5.2 Recommendation for Combining Routes of Exposures for Risk Assessment

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As part of conducting a human health risk assess ment process, the Agency considers risks from individual routes of exposure (oral, dermal, and inhalation). Additi onally, the Agency must assess aggregate risks from dietar y and residential exposures. In order to conduct an aggregate

risk assessment a determination is made if it is appropriate to combine across routes of exposure and aggregate dietary risks with residential (non-occupational) risks. At this time, there are no residential uses for penflufen, so a discussion of combining routes of expos ure is not pertinent to

this assessment.

4.5.3 Cancer Classification and Ri sk Assessment Recommendation

The CARC concluded that penflufen exhibits “Suggestive Evidence of Carcinogenic Potential” based on the presence of statisti cally significant increase in histiocytic sarcomas with a positive trend in male rats only (but in the absence of a dose response and l ack of pre-neopla stic lesions). A marginal increase in brain astrocytomas was al so observed in males at the high dose; however, this effect was not dose-related, did not reach st atistical significance, and there was no overall trend. In addition, there were no pre-neoplastic le sions, such as glial proliferations, which are a good indicator of chemical tumor induction ( i.e., there will be changes in the cells prior to transformation to a neoplasm). The ovarian ad enomas observed at the high dose also showed no dose response, no pair-wise significance, no decrease in latency, and there were no preneoplastic lesions such as hyperp lasia of the epithelia l cells of the endometrium. Additionally, there was no evidence of carcinogenicity in male or female mice (at doses that were judged to be adequate to assess the carcinogenic pote ntial), no concern for mutagenicity ( in vivo or in vitro) for the parent molecule or the two metabolites, an d there were no other lines of evidence (such as structure-activity relationship) . Therefore based on the single line of limited evidence for carcinogenicity (histiocytic sarcomas in male rats), a stronger conclusion for carcinogenic potential could not be supported and thus, the weight of evidence is s uggestive of carcinogenic potential for penflufen. Also, according the Guidelines, when there is a “Suggestive” classification, the Agency does not attempt a dose-response assessment, as the nature of the data generally would not support one. Therefore, the Agency has dete rmined that quantification of risk using a non-linear approach (i.e., RfD) w ill adequately account for all chronic toxicity, including carcinogenicity, which could resu lt from exposure to penflufen. The NOAEL (38 mg/kg/day) used for establishi ng the Chronic RfD is approximate ly 10-fold lower than the dose (approximately 300 mg/kg/day) that induced a marg inal non-significant increase in brain tumors

in male rats.

4.5.4 Summary of Points of Departure and T oxicity Endpoints Used in Human Risk

Assessment

Table 4.5.3 summarizes the toxicolo gical doses and endpoints select ed for the acute and chronic dietary risk assessments and non-occupational inha lation exposure scenarios for penflufen. Table 4.5.4 summarizes the toxicological doses and endpoints selected for the short- and intermediateterm occupational inhalation expos ure scenarios for penflufen.

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Table 4.5.3 Summary of Toxicological Doses and Endpoints for Penflufen for Use in Dietary and Residential (Non-Occupational) Human Health Risk Assessments

Exposure/

Scenario Point of Departure Uncertainty/FQPA Safety Factors RfD, PAD,

Level of

Concern for

Risk

Assessment Study and Toxicological Effects Acute Dietary (All populations, including

children and

women 13-49 years of age) NOAEL=

50 mg/kg/day UF A = 10 x

UF H =10 x FQPA SF = 1x Acute RfD = 0.50 mg/kg/day

aPAD =0.5 mg/kg/day Acute neurotoxicity study in rats (MRID 48023829) LOAEL = 100 mg/kg, based on decreased motor and locomotor activity (39-81% on day of treatment) in females

Chronic Dietary (All Populations) NOAEL=

38 mg/kg/day UF A = 10 x

UF H =10 x FQPA SF = 1x Chronic RfD =

0.38 mg/kg/day

cPAD = 0.38 mg/kg/day Chronic toxicity study in dogs (MRID 48023813) LOAEL = 357/425 mg/kg/day, based on decreased terminal body weight and body weight gain (females), increased prothrombin time (males), increased alkaline phosphate activity, decreased cholesterol , increased GGT levels, decreased albumin and albumin/globulin ratio, decreased calcium and phosphorus , increased liver weights , increased incidence of focal hepatocellular brown pigment and hepatocellular hypertrophy, and an increased incidence of thyroid follicular cell hypertrophy in both sexes,

and in increased incidence of zona glomerulosa vacuolation of the adrenal gland in females.

Inhalation

Short- Term (1-30 days) NOAEL=

55.7 mg/kg/day UF A = 10 x

UF H =10 x FQPA SF = 1x Nonoccupational

LOC for MOE

= 100 Subchronic oral toxicity study in dogs (MRID 48023808) LOAEL = 532/568 mg/kg/day, based on decreased body weight/body weight gain (females), clinical chemistry changes, increased liver weights, and increased incidence of hepatocellular hypertrophy in both sexes, and an increased incidence of slight diffuse cortical hypertrophy/hyperplasia in the adrenal in

males.

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Table 4.5.3 Summary of Toxicological Doses and Endpoints for Penflufen for Use in Dietary and Residential (Non-Occupational) Human Health Risk Assessments

Exposure/

Scenario Point of Departure RfD, PAD,

Level of

Concern for Uncertainty/FQPA Risk Safety Factors Assessment Study and Toxicological Effects

Inhalation

IntermediateTerm (1-6 months) NOAEL=

38 mg/kg/day

Assume

inhalation toxicity equivalent

to oral toxicity UF A = 10 x

UF H =10 x FQPA SF= 1 x Residential

LOC for MOE

= 100 Chronic toxicity study in dogs (MRID 48023813) LOAEL = 357/425 mg/kg/day, based on decreased terminal body weight and body weight gain (females), increased prothrombin time (males), increased alkaline phosphate activity, decreased cholesterol, increased GGT levels, decreased albumin and albumin/globulin ratio, decreased calcium and phosphorus, increased liver weights, increased incidence of focal hepatocellular brown pigment and hepatocellular hypertrophy, and an increased incidence of thyroid follicular cell hypertrophy in both sexes,

and increased incidence of zona glomerulosa vacuolation of the adrenal gland in females. Cancer (oral, dermal, inhalation) Classification: “Suggestive”. Quantification of ri sk using a non-linear appr oach (i.e., RfD) will adequately account for all chronic toxicity, in cluding carcinogenicity that could result from exposure to penflufen.

Point of Departure (POD) = A data point or an estimated point that is derived from obs erved dose-response data and used to mar k the beginning of extrapolation to determine risk associ ated with lower environmentally relevant human exposures. NOAEL = no observed adverse effect level. LOAEL = lowest observed adverse effect level. UF = uncertainty factor. UF A = extrapolation from animal to human (interspecies). UF H = potential variation in sensitivity among members of the human popula tion (intraspecies). FQPA SF = FQPA Safety Factor. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dos e. MOE = margin of exposure. LOC = level of concern.

5.0 Dietary Exposure and Risk Assessment

5.1 Metabolite/Degradate Residue Profile

5.1.1 Summary of Plant and Livestock Metabolism Studies

5.1.1.1 Plant Metabolism Studies

Plant metabolism data were submitted for potato (seed treatment and in-furrow applications), wheat (seed treatment), soybean (seed treatment), and rice (at transplant) to support the requested new uses of penflufen. Studies for all commodities reflected labeling in both the phenyl and pyrazole rings, application rates were equal to, or exaggerations of the currently proposed use rates and application tec hniques reflect the request application patterns.

The metabolic pathway in potatoes, wheat, soybeans and rice is substantially similar. Following seed treatment or in-furrow use of penflufen in potatoes, wheat, soybeans and rice, degradation appears to follow three major pathways: 1) su bstitution of glutathione for fluorine on the pyrazole ring followed by hydrolysis of the glutat hione moiety to cysteine; 2) hydroxylation of

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the third or fourth carbon on the butyl substi tuent, followed by conjugation with glucose and malonic acid; and 3) cleava ge of the N-phenyl linkage.

While the proposed metabolic pathways for these cr ops are similar, in the absence of data on a fruiting vegetable, this data set is not considered adequate to define the na ture of the residue in all plants. Further, since the a pplication techniques were limited to seed treatment, in-furrow or at transplant (rice), these data will not support foliar uses of penflufen on agricultural crops. However, the submitted metabolism data are considered adequate to support the requested seed treatment uses on alfalfa, legume vegetables, cereal grains, oils seeds and the use on potatoes as a seed piece treatment and a si ngle in-furrow application.

A summary of the major findings from each of the plant metabolism studies are included in Appendix B.

5.1.1.2 Livestock Metabolism Studies

Livestock metabolism studies were submitted for the hen (poultry) and lactating goat (ruminant) for penflufen to support the requested new uses. Studies in both animals reflected labeling in both the phenyl and pyrazole rings.

Penflufen is extensively metabolized in the hen and lactating goat. The metabolic pathways in poultry and ruminants appear similar. No differe nce in metabolic profile was noted between the pyrazole and phenyl ring labeled studies. The ma in metabolic pathways in livestock involve Ndemethylation in the pyrazole ring, hydroxylation at various positions in the molecule, oxidation to keto and to carboxylic acid groups, conjugation s with glucuronic acid and cleavage of the Nphenyl and carboxamide bond.

The submitted livestock metabolism studies adequate ly address the requirement to elucidate the nature of the residue in livestock for penflufe n. The Agency has determined that the newly proposed uses of penflufen are classified as 180.6 (a) (3), no reasonable expectation of finite residues with respect to residues in a livestock commodities since quantifiable residues are not likely to be present in the livestock feedst uffs associated with this petition.

A summary of the major findings from the laying hen and goat metabolism studies are included in Appendix B.

5.1.2 Summary of Environmental Degradation
Drinking Water Memo, D386698, R. Baris, 8/25/10

Penflufen is persistent in aer obic and anaerobic cond itions, and is moderately mobile based on the FAO Soil mobility classifications (m ean Koc = 365; MRID 48023546) (USEPA, 2006). Penflufen is persistent in soil with half-lives ranging from 115 to 433 days in aerobic soil from

two studies conducted in si x soils (MRID 48023552, 48023553). It degrades very slowly in

anaerobic soil with an extrapolated half-life of 886 days (combined label; MRID 48023555). There is no evidence of degradation via hydrolys is, which was studied across environmental pHs (pH 5, 7, and 9 at 50oC; MRID 48023547). Penflu fen degraded slowly by aerobic aquatic metabolism with half-lives ranging from 267 to 301 days (MRID 48023556); there is no

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evidence of degradation in anaerobic aquati c systems (MRID 48023557). The primary route of degradation is via aqueous photol ysis (17 days, corrected environmental half-life of 83.2 days; MRID 48023548); however photolysis only plays a si gnificant role in shallow clear waters. Penflufen and its residues of concern (Pen-3HB , and AAP) are expected to persist in both the terrestrial and aquatic environmen ts. Pen-3HB is much more mobile than the parent, but the AAP degradate is comparatively immobile. Under aerobic conditions, the compound can be slowly metabolized, but it is stable to anaerobic metabo lism. AAP will persist with half-lives ranging from 116-260 days (there is no metabolism data for the Pen-3HB degradate). Penflufen was

detected in the submitted terrestrial field diss ipation studies above th e level of quantitation (LOQ) up to 60cm depth, however the majority of the detections were only reported in the upper soil layers (0-15 cm).

5.1.3 Comparison of Metabolic Pathways

The metabolism of penflufen in the rat is detailed in Section 4.2 and the metabolism in plants and

livestock is discussed in Section 5.1.1. Based on the submitted data, th e metabolic profile in plants is similar in potatoes, cereal grains, oilseeds and legumes . Metabolism in the rat and livestock (ruminants and poultry) is similar and, in animals, penflufen is extensively metabolized and conjugated. The metabolites identified in th e plant metabolism studies are either found as metabolites in the animal studies, or are intermedia ries in the metabolic pathways elucidated in animals; therefore, there are no residues of c oncern in plant studies, nor are there any unique metabolic pathways in the plant, that are not represented in the rat metabolism study.

5.1.4 Residues of Concern Summary and Rationale
ROCKS Memo, D387299, W. Irwin, 6/15/2011

The HED Residues of Concern Knowledgebase Sub-committee (ROCKS) considered the available data on the nature and magnitude of re sidues in penflufen and has concluded that for plants, the parent compound onl y be included for tolerance en forcement and dietary risk assessment. At this time, there is no reasonable e xpectation of finite residues in livestock so the

committee had no recommendation on residues of con cern in livestock. For drinking water, the ROCKS recommended including the parent, penflufen-3-hydroxybutyl (Pen-3HB), and penflufen-pyrazolyl-AAP. The reasoning behind these recommendations is as follows:

• Hazard Considerations: Techni cal penflufen displayed low acute toxicity via the oral, dermal and inhalation routes of exposure (T oxicity Categories III a nd IV). Increased liver weight, hepatocellular hypertrophy, and thyroid hypertrophy were observed in several animal studies throughout the penflufen toxicity data base. Reproductive toxicity (delayed sexual maturation) was observed in females in both generations in the rat reproduction study. There are no neurotoxicity or mutagenicity concerns. Mutagenicity studies with penflufen-pyrazolyl-AAP and Pe n-3HB were also negative for mutagenic activity. However, penflufen is “suggestiv e” for carcinogenicity but not sufficient for quantitation of cancer risk in humans. A stru cture activity analysis of penflufen and its major metabolites using DEREK v.12 did not raise any concer ns for toxic effects that were not already observed in the toxicity database.

• Drinking Water: Parent penflufen, and the metabolites Pen-3HB and penflufenPage 24 of 106Penflufen Human Health Risk Assessment D387450

pyrazolyl-AAP (AAP) were identified as potenti al major degradates in drinking water. Penflufen is relatively stable in soil degr adation studies (t1⁄2 > 100 days) and is not susceptible to hydrolysis. Concentrations of the degradates were in creasing at the end of the degradation studies precluding accurate meas ures of half-lives. Therefore, there is a reasonable expectation of exposure to thes e compounds. Since the structures of the metabolites are similar to the parent, they are assumed to have similar toxicities. Therefore, ROCKS recommended that parent penflufen, Pen-3HB and AAP be included as residues of concern for drinking water. In addition, since penflufe n is susceptible to photolysis, the ROCKS committee recommended that the metabolites M60 (fluoro acid) and M64 (bis-desmethyl-3-carboxylic acid) be reassessed should there be any uses proposed where aqueous photolysis may be a significant route of environmental dissipation.

• Primary/Rotational crops: The proposed use fo r penflufen is seed treatment or in-furrow treatment (potatoes only) so the ROCKS reco mmendation is based on these uses only. Since the metabolic and degradation pathways for primary/rotational crops are similar, all crops will be discussed together.

Residues identified in the plant metabolism and confined rotational studies included parent, Pen-3HB, Pen-HGT, Pen-PCX, and Pen- D3C. Total residues in the plant are low in the primary crop metabolism studies, which re flect the proposed seed treatment uses. In confined rotational crop studi es at 3X application rates, some metabolites were in the ppb range (i.e., Pen-3HB); at exaggerated app lication rates of up to 10X, only low levels of parent were measured in forage materi als. Similarly, residues were low or nondetectable in field trials. Of those that we re identified, they were largely conjugated and most likely to be found in livestock feed stuffs and are a lesser concern. Based on structure and SAR analysis, the metabolites iden tified in the plant studies are not likely to be more toxic than the parent penflufen.

Therefore, due to the low quantities identifie d, the conjugated nature of the residues that were identified, and likelihood that the residu es will be found in livestock feedstuff at minimal levels, the ROCKS recommended pare nt only be included for risk assessment

and tolerance. If there is gross misuse, there is likely to be parent residues that would be an adequate indicator of misuse.

The residues of concern for penflufe n are summarized in table 5.1.4, below.

Page 25 of 106Penflufen Human Health Risk Assessment D387450

Table 5.1.4. Penflufen Residues to be Included in the Risk Assessment and Tolerance Expression.

Matrix Residues included in Risk Assessment Residues included in Tolerance Expression for Compliance Monitoring

Plants Primary Crop Penflufen Penflufen

Rotational Crop Penflufen Penflufen

Livestock Ruminant Not applicable; no expectation of finite

residues in livestock commodities. Not applicable; no expectation of

finite residues in livestock

commodities. Poultry Not applicable; no expectation of finite

residues in livestock commodities. Not applicable; no expectation of

finite residues in livestock

commodities. Drinking Water Penflufen plus metabolites penflufenhydroxybutyl and penflufen-pyrazolylAAP N/A

Penflufen Parent: N -[2-(1,3-dimethylbutyl)phenyl]-5-fluoro-1,3-dimethyl-1 H -pyrazole-4-carboxamide Penflufen-hydroxybutyl: Pen-3HB, 5-fluoro- N -[2-(3-hydroxy-1,3-dimethylbutyl)phenyl]-1,3-dimethyl-1 H -pyrazole-4-

carboxamide Penflufen-pyrazolyl-AAP: N -(2-acetylphenyl)-5-fluoro-1,3-dimethyl-1 H -pyrazole-4-carboxamide

5.2 Food Residue Profile

The submitted data on the metabolism of penflufen in potatoes (seed treatment and in-furrow), wheat (seed treatment), soybeans (seed treatment) and rice (in soil at transp lant) demonstrate that residues are generally lo w, but do translocate throughout the pl ants. The highest residues are generally found in the foliage or forage portions of plants (feed items), and not in the tubers, seeds or grains of these commodities (food items ). The registrant has provided studies on sunflower, cotton, canola, beans, peas and al falfa that demonstrate there is no uptake of radioactivity into any aerial po rtion of those plants; indicating that penflufen is not taken up by these plants and that there is li ttle likelihood of exposure to penf lufen from consuming the edible portion of these commodities. Field trial data submitted for the remaining commodities showed no quantifiable residues of penflu fen in any of the food or feed stuff associated with those

commodities.

Adequate residue chemistry data have been provid ed for penflufen. Field trials are of adequate number and geographic representation, were gene rated using adequate analytical methods and are supported by adequate storage stability data . Adequate studies were submitted for corn, wheat, soybean and potato to elucidate the fate of penflufen in processed commodities derived from these crops. The Agency has determined that the newly proposed uses of penflufen are classified as 180.6 (a) (3), no reas onable expectation of finite resi dues with respect to residues in livestock commodities since quantifiable residues ar e not likely to be present in the livestock feedstuffs associated with this petition. Confined rotational crops studies show that the metabolism of penflufen in rotated crops is similar to that in prim ary crops. Limited field trials generated using validated analytic al methods and supported by adequa te storage stability data are of adequate number and geographi c representation to demonstrate that residues are not likely in any commodity planted 30-days after initially planting penflufen-treated seeds.

Page 26 of 106Penflufen Human Health Risk Assessment D387450

5.3 Water Residue Profile
Drinking Water Memo, D386698, R. Baris, 8/25/10

Penflufen is a new chemical; therefore, there ar e no monitoring data curren tly available for this active ingredient or its residues of concern in drinking water. Estimated drinking water concentrations (EDWCs) were generated using OPP’s standard suite of models. The screening model FIRST (FQPA Index Reservoir Screeni ng Tool, version 1.1, 01/01/07) was used to

calculate the surface water EDWCs. Estimated groundwater EDWCs were calculated using the screening model SCI-GROW (Screening Concen trations in Ground Water, version 2.3, 07/29/03).

Maximum application rates for penflufen as a hi gh-end estimate of exposure in drinking water were modeled based on the proposed labels. Ch emical specific and model input values were chosen in accordance with current input pa rameter guidance (USEPA , 2009). The two major degradates of penflufen (pen-3HB and AAP) were included in this expos ure assessment. Total

toxic residue half-lives were calculated for parent + pen-3HB + AAP. The degradation studies were characterized by large amount of un-extracted and uncharacter ized material; thus there is considerable uncertainty regardi ng the degradation of pe nflufen residues in the environment. To characterize this uncertainty, model simulations were completed using high-end conservative

estimates which used half-lives that included un- extracted residues. However, supplemental data submitted by the applicant show that a large portion of the un-extracted residues are potentially biologically mediated and may be irreversibly bound; EDWCs excludi ng un-extracted residues

would be lower than the estimates provided in Table 5.3 (MRID 48652501). Standard default percent cropped areas (PCA) were used for all agricultural uses as estimates of the extent of watershed on which crops is grown (Effland et al. , 1999); the default agricultural PCA of 0.87 was applied. The use of penflufen as both a seed piece treatment and in-furrow banded application to potatoes genera ted the highest EDWCs for both ground and surface water. The maximum surface and ground water EDWCs for use in the human health risk assessment for penflufen are shown in Table 5.3.

Table 5.3 Maximum Estimated Surface Water and Gr oundwater Drinking Water Concentrations for Penflufen and Major Degradates 1

.
Scenario Surface Water Conc., ppb 2 Groundwater Conc., ppb 3

Acute 11.4 16.6

Chronic (non-cancer) 1.8 16.6

1 EDWCs are the total of penflufen, Pen-3HB and AAP, the residues of concern in drinking water.

2 From the Tier I FQPA Index Reservoir Screening Tool, version 1.1; potato (seed treatment and in-furrow total application 0.28 lbs ai/A) scenario.

3 From the SCI-GROW model; potato scenario.
Highest value for use in ri sk assessment is shown in bold.

5.4 Dietary Risk Assessment

5.4.1 Description of Residue Data Used in Dietary Assessment

The acute and chronic dietary risk assessment us ed tolerance level residues for all commodities

included in the assessment.

Page 27 of 106Penflufen Human Health Risk Assessment D387450

5.4.2 Percent Crop Treated Used in Dietary Assessment

The acute and chronic dietary risk assessmen t assumed 100% crop treated for all commodities

included in the assessment.

5.4.3 Acute Dietary Risk Assessment

A highly conservative acute diet ary risk assessment was conducte d which used tolerance level residues, assumed 100 percent crop treated (% CT ) for all commodities, incorporated a DEEMTM default processing factor for dried potatoes and included Tier I modeled drinking water estimates. The estimated exposure (food and water) to the U.S. population and all modeled populations from the proposed new uses of penflufen resulted in an estimated risk equivalent to <1% of the acute popu lation adjusted dose (aPAD) at the 95 th percentile.

5.4.4 Chronic Dietary Risk Assessment

A highly conservative chronic di etary risk assessment was conducted which used tolerance level residues, assumed 100 percent crop treated (% CT ) for all commodities, incorporated a DEEMTM default processing factor for dried potatoes and included Tier I modeled drinking water estimates. The estimated exposure (food and water) to the U.S. population and all modeled populations from the proposed new uses of penflufen resulted in an estimated risk equivalent to <1% of the chronic populat ion adjusted dose.

5.4.5 Cancer Dietary Risk Assessment

The Agency has classified penflufen as “suggest ive of carcinogenicity” and has concluded that the chronic population adjusted dose is protectiv e of all chronic effect s, including potential carcinogenicity. The results of the chronic dietary risk assessment are discussed in Section 5.4.4.

5.4.6 Summary Table

Table 5.4.6. Summary of Dietary (F ood and Drinking Water) Exposure and

Risk for Penflufen

Population Subgroup Acute Dietary (95th Percentile) Chronic Dietary

Dietary Exposure (mg/kg/day) % aPAD* Dietary Exposure (mg/kg/day) % cPAD*

General U.S. Population 0.000949 <1% 0.000407 <1%

All Infants (< 1 year old) 0.003364 <1% 0.001231 <1%

Children 1-2 years old 0.001546 <1% 0.000650 <1%

Children 3-5 years old 0.001404 <1% 0.000613 <1%

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Table 5.4.6. Summary of Dietary (F ood and Drinking Water) Exposure and

Risk for Penflufen

Acute Dietary Chronic Dietary (95th Percentile)

Population Subgroup Dietary Dietary Exposure Exposure (mg/kg/day) % aPAD* (mg/kg/day) % cPAD*

Children 6-12 years old 0.000975 <1% 0.000424 <1%

Youth 13-19 years old 0.000777 <1% 0.000312 <1%

Adults 20-49 years old 0.000857 <1% 0.000373 <1%

Adults 50+ years old 0.000773 <1% 0.000381 <1%

Females 13-49 years old 0.000856 <1% 0.000369 <1%

6.0 Residential (Non-Occupational) Exposure/Risk Characterization

Residential exposures and risk are not assessed because the proposed us es of penflufen do not involve applications by homeowners or commercial applicators in residential settings at this time and there are no existing or proposed residential uses.

6.1 Spray Drift

A postapplication inhalation exposure assessment is not required as exposur e is expected to be negligible. Seed treatment a ssessments provide quantitative i nhalation exposure assessments for seed treaters and secondary handlers (i.e. planters). It is expected that these exposure estimates would be protective of most postapplic ation inhalation exposure scenarios.

In-furrow potato piece treatment can be applied by spray; however, the pathway from furrow to drift is likely to be negligible due to the spray be ing applied as a soil-direc ted spray that is then immediately covered as part of the planting process.

7.0 Aggregate Exposure/Risk Characterization

There are no residential uses for penflufen; therefore the aggregate exposure and risk assessments include acute and chronic dietary (food and water) only and are shown in Section 5.4.3 and 5.4.4. There are no aggregate risk estimate s of concern for the proposed new uses of penflufen.

Page 29 of 106Penflufen Human Health Risk Assessment D387450

8.0 Cumulative Exposure/Ri sk Characterization

Unlike other pesticides for which EPA has fo llowed a cumulative risk approach based on a common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as to penflufen and any other substances and pe nflufen does not appear to produce a toxic metabolite produced by other substances. For the purposes of this tolerance action, therefore, EPA has not assumed that penflufen has a common mechanism of toxicity with other substances. For information regarding EPA’s efforts to determine which chemicals have a common mechanism of toxicity and to ev aluate the cumulative effects of such chemicals, see the policy statements released by EPA’s Office of Pe sticide Programs concerning common mechanism determinations and procedures for cumulating e ffects from substances found to have a common mechanism on EPA’s website at http ://www.epa.gov/pesticides/cumulative/.

9.0 Occupational Exposure/ Risk Characterization

9.1 Short-/Intermediate-Term Handler Risk

Occupational handler exposure to penflufen is e xpected for individuals involved in commercial

seed treatment and on-farm seed treatment. Ex posure during in-furrow potato piece treatment is also expected. Occupational seed treatmen t primary handlers may experience short- and intermediate-term exposure to penflufen while performing seed trea tment activities in commercial settings. In addition, occupational secondary handlers may experience short- and intermediate-term exposure while planting penflu fen-treated seeds. No chemical-specific handler exposure data were submitted in support of this use pattern. For assessing commercial seed treatment and seed planting activities, uni t exposure data were ta ken from HED ExpoSAC Policy 14: SOPs for Seed Treatment and MR ID 47054702 (Study Review of “Determination of Dermal and Inhalation Exposure of Workers during On-Farm Seed Piece Treatment of Potatoes”. MRID 47054702. Bayer CropScience. D378750, S. Tadayon, 6/23/10). The amount of active ingredient handled depends on the application rate (lb ai/lb seed) and the pounds of seed treated in a day (or the pounds of seed that can be plan ted in a day), all of which vary depending upon the seed type. Values for the amount of seed treated and planted per day were obtained from HED ExpoSAC Policy 15. For the potato seed piece treatment exposure assessment, unit exposures were also used from the Occupati onal Pesticide Handler Unit Exposure Surrogate

Reference Table.

Quantification of dermal exposure and risk is not required since a dermal hazard has not been identified for penflufen. Only inhalation expos ure and risks were quant ified. The occupational inhalation exposure assessment was completed for commercial seed treatments. On-farm seed treatment utilizes similar machinery as commerci al seed treatment; the only difference being the size of the equipment. With the specific labels restricting direct pr oduct use in hopper-boxes, planter-boxes, and slurry-boxes, the assessed commercial seed tr eatment exposure and risk is protective of on-farm seed treatment scenarios. The proposed personal protective equipment (PPE) for penflufen on all proposed labels requires that all mixers, loaders, applicators and other

Page 30 of 106Penflufen Human Health Risk Assessment D387450

handlers to wear long sleeved shirt and long pant s, socks plus shoes, and chemical resistant gloves (except when bagging or sewing bags of treated seeds).

Short- and intermediate-term handler exposures a nd risk estimates for seed treatment activities are shown in Tables 9.1.1, 9.1.2, 9.1.3 and 9.1.4, below. All inhalation risk estimates greatly exceed HED’s level of concern and; therefore, are not of concern.

Table 9.1.1. Summary of Short- and Intermedia te-Term Handler Exposures and Risks for Penflufen (Seed Treatment Only).

Seed Type Inhalation

UE a Max App Rate b Amt Treated c Inhalatopm

Dose d Short-Term

Inhal MOE e IntermediateTerm Inhal

MOE f

mg/lb lb ai/lb seed lb seed/day mg/kg/day LOC = 100 LOC = 100
LOADER/APPLICATOR (no respirator)

Alfalfa 0.00034 0.00015 718,000 0.00052 110,000 73,000

Beans and Peas 0.00034 0.00005 194,000 0.000047 1,200,000 810,000
Soybean 0.00034 0.00005 718,000 0.00017 320,000 220,000
Cereal Grains,

incl. Rice 0.00034 0.00005 718,000 0.00017 320,000 220,000

Canola 0.00034 0.00015 104,000 0.000076 740,000 500,000

Field Corn 0.00034 0.0001 550,000 0.00027 210,000 140,000

Sweet Corn 0.00034 0.0001 194,000 0.000094 590,000 400,000

Cotton 0.00034 0.0001 160,000 0.000078 720,000 490,000

Sunflower and

safflower 0.00034 0.00015 718,000 0.00052 110,000 73,000

Sorghum 0.00034 0.0001 718,000 0.00035 160,000 110,000
SEWER (no respirator)

Alfalfa 0.00023 0.00015 718,000 0.00035 160,000 110,000

Beans and Peas 0.00023 0.00005 194,000 0.000032 1,700,000 1,200,000
Soybean 0.00023 0.00005 718,000 0.00012 470,000 320,000
Cereal Grains,

incl. Rice 0.00023 0.00005 718,000 0.00012 470,000 320,000

Canola 0.00023 0.00015 104,000 0.000051 1,100,000 740,000

Field Corn 0.00023 0.0001 550,000 0.00018 310,000 210,000

Sweet Corn 0.00023 0.0001 194,000 0.000064 870,000 600,000

Cotton 0.00023 0.0001 160,000 0.000053 1,100,000 720,000

Sunflower and

safflower 0.00023 0.00015 718,000 0.00035 160,000 110,000

Sorghum 0.00023 0.0001 718,000 0.00024 240,000 160,000
BAGGER (no respirator)

Alfalfa 0.00016 0.00015 718,000 0.00025 230,000 150,000

Beans and Peas 0.00016 0.00005 194,000 0.000022 2,500,000 1,700,000
Soybean 0.00016 0.00005 718,000 0.000082 680,000 460,000
Cereal Grains,

incl. Rice 0.00016 0.00005 718,000 0.000082 680,000 460,000

Canola 0.00016 0.00015 104,000 0.000036 1,600,000 1,100,000

Field Corn 0.00016 0.0001 550,000 0.00013 440,000 300,000

Sweet Corn 0.00016 0.0001 194,000 0.000044 1,300,000 860,000

Cotton 0.00016 0.0001 160,000 0.000037 1,500,000 1,000,000

Sunflower and 0.00016 0.00015 718,000 0.00025 230,000 150,000

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Table 9.1.1. Summary of Short- and Intermedia te-Term Handler Exposures and Risks for Penflufen (Seed Treatment Only).

Seed Type Inhalation

UE a Max App Rate b Amt Treated c Inhalatopm

Dose d Intermediate- Short-Term Term Inhal Inhal MOE e MOE f

mg/lb lb ai/lb seed lb seed/day mg/kg/day LOC = 100 LOC = 100

safflower
Sorghum 0.00016 0.0001 718,000 0.00016 340,000 230,000

Page 32 of 106Penflufen Human Health Risk Assessment D387450

Table 9.1.1. Summary of Short- and Intermedia te-Term Handler Exposures and Risks for Penflufen (Seed Treatment Only).

Seed Type Inhalation

UE a Max App Rate b Amt Treated c Inhalatopm

Dose d Intermediate- Short-Term Term Inhal Inhal MOE e MOE f

mg/lb lb ai/lb seed lb seed/day mg/kg/day LOC = 100 LOC = 100

MULTIPLE ACTIVITIES (no respirator)

Alfalfa 0.0016 0.00015 718,000 0.0025 23,000 15,000

Beans and Peas 0.0016 0.00005 194,000 0.00022 250,000 170,000
Soybean 0.0016 0.00005 718,000 0.00082 68,000 46,000
Cereal Grains,

incl. Rice 0.0016 0.00005 718,000 0.00082 68,000 46,000

Canola 0.0016 0.00015 104,000 0.00036 160,000 110,000

Field Corn 0.0016 0.0001 550,000 0.0013 44,000 30,000

Sweet Corn 0.0016 0.0001 194,000 0.00044 130,000 86,000

Cotton 0.0016 0.0001 160,000 0.00037 150,000 100,000

Sunflower and

safflower 0.0016 0.00015 718,000 0.0025 23,000 15,000

Sorghum 0.0016 0.0001 718,000 0.0016 34,000 23,000

a Unit Exposures from HED Exposure Science Advisory Council Policy 14 (baseline inhalation = no respirator). b Application Rates based on propos ed label uses for penflufen. c HED default for lb seed treated per day from HED Exposure Science Advisory Council Policy 15; wheat used as surrogate for alf alfa. d Daily Inhalation Dose (mg/kg/day) = daily inhalation unit exposure (mg/lb ai) x app lication rate (lb ai/lb seed) x amount tre ated (lb seed/day) x absorption factor (100%) / body weight (70 kg adult). e Short-term Inhalation MOE = NOAEL (55.7 mg/kg/day for short-te rm exposure) / Inhalation Dose (mg/kg/day). Level of concern = 100.

f Intermediate-term Inhalation MOE = Intermediate-term NOAEL (38 mg/kg/day for intermediate-term exposure) / Inhalation Dose ( mg/kg/day).

Level of concern = 100.

Table 9.1.2. Short- an d Intermediate-Term Occupa tional Handler Exposures and Risks for In-Furrow

and Potato Seed Piece Treatment.

Application

Rate a Amount

Treated Per Day c Unit Exposures b Dose d
mg/kg/day MOEs

LOC = 100

Baseline Inhalation Baseline Inhalation e Short-term

Baseline

Inhalation f IntermediateTerm Baseline

Inhalation g lb ai/A Acres/day μg/lb ai

Mixer/Loader

0.12 200 0.219 0.000075 740,000 510,000

Groundboom Applicator- Surrogate for In-furrow potato treatment

0.12 200 0.34 0.000117 480,000 330,000

a Application Rates based on proposed uses on label. b Acres treated per day from ExpoSAC Policy 9. c Baseline inhalation unit exposures represent no respirator prot ection. All values are reported in the Occupational Pesticide Handler Unit

Exposure Surrogate Reference Table dated Sept ember 2011, using PHED, AHETF, and ORETF data. d Baseline Inhalation: no respirator. e Inhalation Dose (mg/kg/da y) = daily unit exposure ( μ g/lb ai) x application rate (lb ai/A) x am ount treated /day (acres/day) x conversion factor (1 mg/1,000 μ g) x inhalation absorption factor (100%) / body weight (70 kg adult). f Inhalation MOE = short-term NOAEL (55.7 mg/kg/day) / inhalation daily dose (mg/kg/day). Level of concern = 100. g Inhalation MOE = intermediate-term NOAEL (38 mg/kg/day) / inhalation daily dose (mg/kg/da y). Level of concern = 100.

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Table 9.1.3. Summary of Handler (o n-farm liquid seed piece treatment to potatoes) Exposures and Risks for

Penflufen . (Data from MRID 47054702)

Seed Type* Inhal UE a Max App

Rate b Amt of Seed Planted/Day c Inhalation

Dose d Short-term

Inhalation

MOE e Intermediateterm Inhalation

MOE f

mg/lb lb ai/lb seed lb seed/day mg/kg/day LOC = 100 LOC = 100

Potato Pieces 0.0064 0.00002 480,000 0.000878 63,000 43,000

a Unit Exposures from data from MRID 47054702. b Application Rates based on propos ed label uses for penflufen. c Information on amount of potato pieces treated per day from the National Potato Council. d Daily Inhalation Dose (mg/kg/day) = daily inhalation unit exposure (mg/lb ai) x app lication rate (lb ai/lb seed) x amount planted (lb seed/day) x absorption factor (100%) / body weight (70 kg adult). e Short-term Inhalation MOE = NOAEL (55.7 mg/kg/day for short-te rm exposure) / Inhalation Dose (mg/kg/day). Level of concern = 100.

f Intermediate-term Inhalation MOE = NOAEL (38 mg/kg/day for intermediate-ter m exposure) / Inhalation Dose (mg/kg/day). Level of concern

= 100.

Table 9.1.4. Summary of Secondary Ha ndler (Planter) Exposures and Risks for Penflufen (with no respiratory protection)

.

Seed Type* Inhal UE a Max App

Rate b Amt of Seed Planted/Day c Inhalation

Dose d Short-term

Inhalation

MOE e Intermediateterm Inhalation

MOE f

mg/lb lb ai/lb seed lb seed/day mg/kg/day LOC = 100 LOC = 100

Alfalfa 0.0034 0.00015 4,000 0.000029 1,900,000 1,300,000

Beans and PeasSoybean and Garden pea* 0.0034 0.00005 12,000 0.000029 1,900,000 1,300,000

Cereal Grains- Rice and

Wheat* 0.0034 0.00005 30,000 0.000073 760,000 520,000

Corn 0.0034 0.0001 3,000 0.000015 3,800,000 2,600,000

Cotton 0.0034 0.0001 3,600 0.000017 3,200,000 2,200,000

Oilseeds- Safflower* 0.0034 0.00015 8,000 0.000058 960,000 650,000
Sorghum 0.0034 0.0001 800 0.0000039 14,000,000 9,800,000

Potato Pieces 0.0034 0.00002 480,000 0.000466 120,000 82,000

a Unit Exposures from HED Exposure Science Advisory Council Policy 14: Standard Operating Procedures for Seed Treatment. b Application Rates based on propos ed label uses for penflufen. c HED default for lb seed planted per day from HED Exposure Science Advisory Counc il Policy 15, except for potato pieces; Infor mation on

amount of potato pieces treated per day from the National Potato Council. d Daily Inhalation Dose (mg/kg/day) = daily inhalation unit exposure (mg/lb ai) x app lication rate (lb ai/lb seed) x amount planted (lb seed/day) x absorption factor (100%) / body weight (70 kg adult). e Short-term Inhalation MOE = NOAEL (55.7 mg/kg/day for short-te rm exposure) / Inhalation Dose (mg/kg/day). Level of concern = 100.

f Intermediate-term Inhalation MOE = NOAEL (38 mg/kg/day for intermediate-ter m exposure) / Inhalation Dose (mg/kg/day). Level of concern

= 100. * In the case where there are several crops in the crop group asse ssed with the same application rate, the crop with the highes t amount of seeds planted per day was assessed as representative of that crop group (i.e., beans and peas, cereal grains other than corn and sorg hum, oilseeds other than cotton)

9.2 Short-/Intermediate-Term Post-Application Risk

9.2.1 Dermal Postapplication Risk

The potential for post-application exposures follow ing the planting of penflufen-treated seeds is unlikely because sustained levels of contact with treated seed after it has been placed in the soil or other planting media would not be expected because no routine cultura l practice required for the production of agricultural commodities involv es such an activity as defined in the no/low

contact criteria in the Worker Protection Standard (WPS). Also, as no dermal hazard has been

Page 34 of 106Penflufen Human Health Risk Assessment D387450

identified, no quantitative post-ap plication assessment is required for exposure to treated seeds that have already been planted.

The proposed labels require that workers wear long-sl eeved shirt, long pants, shoes, socks and chemical-resistant gloves when opening bags of treat ed seed or loading/pour ing the treated seed. No additional PPE requirements are necessary for labeling of treated seed.

The Worker Protection Standard (WPS) allows work ers to enter treated ar eas without restriction

if there will be no worker contact with the treated seeds in the soil or planting media. Certain tasks, even though they are not routine, may invo lve contact with the soil subsurface (e.g. repair of certain irrigation equipment) and they are cove red by the REI. Therefore, the REI is based on the acute toxicity of the active ingredient s. Note that REI recommendations include consideration of penflufen as we ll as any co-formulant (s) in the end-use product. A 12-hour REI is appropriate for seeds that have been planted that were treated with penflufen, clothianidin, prothioconazole, and/or trifloxys trobin. For products containi ng metalaxyl, a 24-hour REI is appropriate.

PENRED 240FS, PEN240FS, PENCLO 273.5FS, PENTRI 308FS, PENPRO 118FS The labeling should state: Bags containing treated seeds shall be labeled with the following

information: “After the seeds have been planted, do not enter or allow worker entry into treated areas during the restricted-entry interval (REI) of 12 hours. Exception: Once the seeds are planted in soil or other planting media, the Worker Protection Standard allows workers to enter the treated area

without restriction if there will be no worker contact with the trea ted seeds in the soil or planting media.” This label requirement is not currently on the proposed labels.

PENCLOTRIME 310.68FS The proposed label requires bags containing treated seeds be labeled to require an REI of 24 hours after seeds have been plante d, with the exception that once th e seeds are planted in soil or other planting media, the Worker Protection Standard allows workers to enter the treated area

without restriction if there will be no worker contact with the trea ted seeds in the soil or planting media. This requirement is on the proposed label for PENCLOTRIME 310.68FS; no change is required.

For PENPROME 177FS The labeling should state: Bags containing treated seeds shall be labeled with the following

information: “After the seeds have been planted, do not enter or allow worker entry into treated areas during the restricted-entry interval (R EI) of 24 hours. Exception: Once the seeds are planted in soil or other planting media, the Worker Protection Standard allows workers to enter the treated area

without restriction if there will be no worker contact with the trea ted seeds in the soil or planting media.” This label requirement is not currently on the proposed label.

Page 35 of 106Penflufen Human Health Risk Assessment D387450

9.2.2 Inhalation Postapplication Risk

A postapplication inhalation exposure assessment is not required as exposur e is expected to be negligible. Seed treatment a ssessments provide quantitative i nhalation exposure assessments for seed treaters and secondary handlers (i.e. planters). It is expected that these exposure estimates would be protective of most postapplic ation inhalation exposure scenarios.

10.0 References

Toxicology References

Author: Jessica Kidwell Date: March 28, 2011

TXR No.: 0051558 Title: Penflufen: Report of the Cancer Assessment Review Committee

Residue Chemistry References

Author: William Irwin Date: June 15, 2011

DP Number: D287299

Title: Penflufen: Report of the Residues of Concern Knowledgebase Sub-committee (ROCKS)

Author: Donna Davis Date: November 15, 2011

DP Number: D395192

Title: Penflufen. New Active Ingredient - New Us es on Alfalfa, Potato (Crop Subgroup 1C), Legume Vegetables (Cr op Group 6 and Crop Group 7), Cereal Grains (Crop Group 15 and Crop Group 16), and Oilseeds (Crop Group 20). Residue Chemistry Summary Document.

Author: Reuben Baris Date: August 25, 2011

DP Number: D386698 Title: Tier I Drinking Water Exposure Asse ssment for the Section 3 New Chemical Registration of Penflufen.

Page 36 of 106Penflufen Human Health Risk Assessment D387450

Author: Donna Davis Date: November 15, 2011

DP Number: D395193

Title: Penflufen. Acute and Chronic Aggregate Di etary (Food and Drinking Water) Exposure and Risk Assessments for Secti on 3 Registration Actions for New Uses on Alfalfa, Potato (Crop Subgroup 1C), Legume Vegetables (Crop Group 6 and Crop Group 7), Cereal Grai ns (Crop Group 15 and Crop Group 16), and Oilseeds (Crop Group 20).

Occupational Assessment References

Author: Alexandra LaMay Date: November 15, 2011

DP Number: D392917

Title: Penflufen; Occupational Exposure Assessment fo r Seed Treatment Use and InFurrow Potato Piece Treatment.

Science Advisory Council for Exposure (ExpoSAC) Policy 14: Standard Operating Procedures (SOPs) for Seed Treatment (May 1, 2003).

ExpoSAC Policy 15: Amount of Seed Treat ed or Planted per Day (March 2, 2004).

Study Review of “Determination of Dermal and Inhalation Exposure of Workers during OnFarm Seed Piece Treatment of Potatoes”. MRID 47054702. Bayer CropScience. D378750, S. Tadayon, 6/23/10.

Occupational Pesticide Handler Unit Exposure Su rrogate Reference Table, US Environmental Protection Agency Office of Pesticide Programs, June 21, 2011.

Page 37 of 106Penflufen Human Health Risk Assessment D387450

Appendix A. Toxicology Prof ile and Executive Summaries

A.1 Toxicology Data Requirements The toxicological data requireme nts (40 CFR 158.340) for food uses for penflufen are in Table A1. Use of the new guideline numbers does not imply that the new (1998) guideline protocols

were used.

Table A.1 Test Technical

Required Satisfied

870.1100 Acute Oral Toxicity 870.1200 Acute Dermal Toxicity 870.1300 Acute Inhalation Toxicity 870.2400 Primary Eye Irritation 870.2500 Primary Dermal Irritation

870.2600 Dermal Sensitization yes

yes

yes

yes

yes

yes yes

yes

yes

yes

yes

yes

870.3100 Oral Subchronic (rat and mouse) 870.3150 Oral Subchronic (dog) 870.3200 21/28-Day Dermal (rat) 870.3250 90-Day Dermal 870.3465 28-Day Inhalation yes

yes

yes CR

CR yes

yes

yes

---

no

870.3700a Developmental Toxicity (rat) 870.3700b Developmental Toxicity (rabbit) 870.3800 Reproduction (rat) yes

yes

yes yes a

yes a

yes

870.4100a Chronic Toxicity (rat) 870.4100b Chronic Toxicity (dog) 870.4200a Carcinogenicity (rat) 870.4200b Carcinogenicity (mouse) 870.4300 Chronic/Carcinogenicity (rat) yes

yes

yes

yes

yes yes

yes

yes

yes

yes

870.5100 Mutagenicity—Gene Mutation - bacterial 870.5300 Mutagenicity—Gene Mutation - mammalian 870.5375 Mutagenicity—Structural Chromosomal

Aberrations 870.5395 Mutagenicity—Mammalian Erythrocyte

Micronucleus 870.5500 Mutagenicity— Bacterial DNA Damage or Repair Test 870.5550 Mutagenicity—Unscheduled DNA Synthesis yes

yes

yes

yes

no

no yes

yes

yes

yes

---

---

870.6100a Acute Delayed Neurotoxicity. (hen) 870.6100b 90-Day Neurotoxicity (hen) 870.6200a Acute Neurotoxicity Screening Battery (rat) 870.6200b 90 Day Neurotoxicity Screening Battery (rat)

870.6300 Developmental Neurotoxicity (rat) no

no

yes

yes CR ---

--- yes

yes

no

870.7485 General Metabolism (rat) 870.7600 Dermal Penetration (8-hour), in vivo (male rat) yes CR yes

yes

Page 38 of 106Penflufen Human Health Risk Assessment D387450

870.7800 Immunotoxic ity (rat and mouse)........................... yes yes

Non-Guideline : Comparative dermal absorption, in vitro (rat and human skin)

Non-Guideline : 28-day oral toxicity (rat)

Non-Guideline : 28-day oral toxicity (mouse)

Non-Guideline : 8-hour dermal penetration, in vivo (male rat) no

no

no

no yes

yes

yes

yes

a ---study acceptable (non-guideline) ); study is non-guideline since the highest dose tested was not high enough to produce a dose response, which is a criteria for a guide line study; additional studies are not required since the endpoints selected are protective of any developmen tal effects that may be seen at higher doses.

A.2 Toxicity Profiles

Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/

Classification /Doses Results

NA 28-Day oral toxicity (rat) 48023838 (2004) Acceptable/non-guideline 0, 150, 2000, 7000 ppm (diet) M: 12, 154, 560 mg/kg bw/day F: 13, 169, 648 mg/kg bw/day NOAEL = 560 mg/kg bw/day (males)/648 mg/kg bw/day (females). LOAEL = not identified; the liver was identified as a major target organ for BYF 14182 (dose-related increase total P-450, BROD, and PROD activities in both sexes, increased cholesterol levels in females, increased liver weight in both sexes, increased incidence of hepatocellular hypertrophy in both sexes). The liver effects are considered adaptive and not adverse.

NA 28-Day oral toxicity (mouse) 48023839 (2005) Acceptable/non-guideline 0, 150, 3500, 7000 ppm (diet) M: 0, 26, 632, 1274 mg/kg bw/day F: 0, 31, 741, 1585 mg/kg bw/day NOAEL = 1274 mg/kg bw/day (males)/1585 mg/kg bw/day (females).

LOAEL = not identified. The liver effects (increased liver weights associated with centrilobular hepatocellular hypertrophy; associated clinical chemistry findings at 7000 ppm) are considered adaptive and not adverse.

NA 28-Day oral toxicity (dog) 48023840 (2005) Acceptable/non-guideline 0, 1300, 6500, 26000 ppm M: 0, 49, 244, and 759 mg/kg bw/day F: 0, 52, 246, and 895 mg/kg bw/day NOAEL = 759 mg/kg bw/day (males)/895 mg/kg/day (females).

LOAEL = not identified. No adverse effects (2 Beagle dogs/sex)

administered BYF 14182 via the diet (28 days); the liver and thyroid were identified as target organs, as evidenced by increased alkaline phosphatase and GGT activities in both sexes, increased liver weight and increased incidences of hepatocellular hypertrophy, thyroid follicular cell hypertrophy, and decreased follicular diameter in the thyroid in both sexes.

Page 39 of 106Penflufen Human Health Risk Assessment D387450

Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/ Results

Classification /Doses

870.3100 90-Day oral toxicity (rat) 48023805(2006) Acceptable/guideline (definitive 90-day rat study, together with the findings of MRID 48023806)

0, 150, 7000, 14000 ppm (diet) M: 0, 9.5, 457 and 949 mg/kg/day F: 0, 11.4, 492 and 1009 mg/kg/day NOAEL = 949 mg/kg bw/day (males)/1009 mg/kg bw/day (females). LOAEL = not identified. The findings at 14000 ppm included an increase in total cholesterol concentration and gamma-glutamyltransferase activity in both sexes, an increase in theincidence of centrilobular hepatocellular hypertrophy, which was correlated with higher liver weights and macroscopically enlarged livers in both sexes, an increased incidence of thyroid follicular cell hypertrophy in both sexes, and

altered colloid in males. These effects are considered an adaptive response and not

adverse.

870.3100 90-Day oral toxicity (rat) 48023806 (2006) Acceptable/guideline (when considered together with the findings of MRID 48023805)

0, 50, 150, 3500 ppm (diet) M: 0, 3.2, 9.3 and 228 mg/kg bw/day F: 0, 3.7, 11.4 and 260 mg/kg bw/day NOAEL = 228 mg/kg bw/day (males)/260 mg/kg bw/day (females).
LOAEL not identified; increased liver weights

and an increased inci dence of centrilobular hepatocellular hypertrophy were observed, which were not accompanied by alterations in relevant clinical chemistry parameters or

adverse liver lesions. The effects observed are considered adaptive and not adverse over this

time frame.

870.3100 90-Day oral toxicity (mouse) 48023807 (2006) Acceptable/guideline

0, 150, 3500, 7000 ppm (diet) M: 0, 26.9, 638, 1238 mg/kg bw/day F: 0, 31.5, 757 and 1600 mg/kg bw/day NOAEL = 1238 mg/kg bw/day (males)/1600 mg/kg bw/day (females). LOAEL = not identified; liver effects are considered adaptive and not adverse.

Page 40 of 106Penflufen Human Health Risk Assessment D387450

Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/ Results

Classification /Doses

870.3150 90-Day oral toxicity (dog) 48023808 (2008) Acceptable/guideline (gavage) M: 0, 5.6, 55.7 and 532 mg/kg bw/day F: 0, 6.1, 63.1 and 568 mg/kg bw/day NOAEL = 55.7 mg/kg bw/day (males)/63.1 mg/kg bw/day (females), based on the minimal liver effects (increased liver weight and hepatocellular hypertrophy), which were not accompanied by significant alterations in relevant clinical chemistry parameters or

adverse liver lesions in both sexes. The effects observed are considered adaptive and not

adverse over this time frame. LOAEL = 532 mg/kg bw/day (males)/568 mg/kg bw/day (females), based on decreased body weight/body weight gain in females, increased alkaline phosphatase activity in both sexes, increased GGT activity in both sexes,

decreased albumin in ma les, increased liver weights in both sexes, increased adrenal weights in males, increased incidence of hepatocellular hypertrophy in both sexes, and an increased incidence of slight diffuse cortical hypertrophy/hyperplasia in the adrenal in

males.

870.3200 28-Day dermal toxicity (rat) 48023809 (2009) Acceptable/guideline 0, 100, 300, or 1000 mg/kg bw/day NOAEL = 1000 mg/kg bw/day

LOAEL = not identified. Increased lymphocyte debris within the thymic cortex ( ♂ / ♀ ; 7/10 each); lesion characterized by the increased presence of fragmented thymic cortical lymphocytes noted within tingible body macrophages; finding not accompanied by a decrease in the size or weight of the thymus or changes in lymphocyte counts. The significance of the finding at the limit dose is not known.

870.3250 90-Day dermal toxicity (species)

870.3465 90-Day inhalation toxicity (species)

Page 41 of 106Penflufen Human Health Risk Assessment D387450

Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/ Results

Classification /Doses

870.3700a Prenatal developmental in (rats) 48023810 (2008) Acceptable/non-guideline 0, 30, 100, or 300 mg/kg bw/day

GD 6-20 Maternal toxicity NOAEL = 300 mg/kg bw/day; findings at the 300 mg/kg/day dose

level are considered minimal. The dose levels do not appear adequate for assessing the developmental toxicity potential of BYF 14182. Although there was a significant reduction in maternal body weight gain at 300 mg/kg/day,

which correlated with a decrease in food consumption, body weights were comparable to those of the control, and the liver changes are considered adaptive and not adverse.
Maternal toxicity LOAEL was not identified

.

Developmental toxicity NOAEL = 300 mg/kg bw/day. At 300 mg/kg/day, the highest dose tested, no adverse effects were observed. However, this dose was a no adverse effect dose level in the range-finding study also. The dose levels are not considered adequate for assessing the developmental toxicity potential

of BYF 14182. Developmental toxicity LOAEL was not

identified. Little concern that new studies would identify a developmental endpoint with a NOAEL lower

than the NOAELs selected for risk assessment.

870.3700b Prenatal developmental in (rabbit) 48023811(2008) Acceptable/non-guideline 0, 30, 100, or 600 mg/kg bw/day

GD 6-28 Maternal NOAEL = 600 mg/kg/day The maternal findings at the 600 mg/kg bw/day dose level are considered minimal. The dose levels do not appear adequate for assessing the developmental toxicity potential of BYF 14182 in the rabbit. Although there was a significant reduction in maternal body weight gain at 600 mg/kg/day, which correlated with a decrease in food consumption, body weights were comparable to those of the control. No other

effects were observed.

Maternal LOAEL was not identified.

Developmental NOAEL = 600 mg/kg bw/day. Developmental toxicity LOAEL was not

identified. Little concern that new studies would identify a developmental endpoint with a NOAEL lower

than the NOAELs selected for risk assessment.

Page 42 of 106Penflufen Human Health Risk Assessment D387450

Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/ Results

Classification /Doses

870.3800 Reproduction and fertility effects (rat) 48023812 (2009) acceptable/guideline 0, 200, 1000, or 4000 ppm (diet) M: 0, 12.8, 64.1, 252.2 mg/kg bw/day F: 0, 15, 75.9, 294.5 mg/kg bw/day Parental/Systemic NOAEL = 64 mg/kg bw/day (males)/76 mg/kg bw/day (females) LOAEL = 252.2 mg/kg bw/day (males)/294.5 mg/kg bw/day (females), based on decreased body weight, decreased body weight gain, alterations in food consumption, decreased thymus weight in both genders, and decreased spleen weights in females (both generations). The increased liver weights and hepatocellular hypertrophy are considered adaptive and not

adverse.

Reproductive NOAEL = 73 mg/kg bw/day LOAEL = 291 mg/kg bw/day, based on delayed

sexual maturation in females in both generations.

Offspring NOAEL = 73 mg/kg bw/day LOAEL = 291 mg/kg bw/day, based on a slight decrease in litter size in both generations,decreased pup body weight and pup bodyweight gain, delayed vaginal patency in both generations, and decreased brain, spleen, and
thymus weights

. 870.4100a Chronic toxicity (rat) 48023815 (2009) Acceptable/guideline 0, 100, 2000 or 7000 ppm (diet) M: 0, 4.0, 79 and 288 mg/kg bw/day F: 0, 5.6, 113 or 399 mg/kg bw/day NOAEL = 2000 ppm (79/113 mg/kg bw/day) LOAEL = 7000 ppm (288/399 mg/kg bw/day), based on decreased body weight/body weight gain in females, increased liver weight in both sexes, increased incidence of centrilobular to panlobular hepatocellular hypertrophy and centrilobular hepatocellular macrovacuolation in both sexes, increased incidence of hepatocellular brown pigment in females, hepatocellular necrosis, colloid alteration in the thyroid in females, and increased cholesterol in

females. These effects are considered mainly adaptive in nature.

Page 43 of 106Penflufen Human Health Risk Assessment D387450

Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/ Results

Classification /Doses

870.4100b Chronic toxicity (dog) 48023813 (2009) Acceptable/guideline 0, 200, 1000, 10000 ppm (diet)

M: 0, 6.8, 32.0 and 357 mg/kg bw/day F: 0, 7.7, 37.9 and 425 mg/kg bw/day NOAEL = 38 mg/kg bw/day. NOAEL is based on the minimal changes in the liver (increased liver weight and hepatocellular hypertrophy, which were not accompanied by relevant changes in clinical chemistry parameters and adverse liver lesions) that are not considered

adverse. LOAEL = 357 mg/kg bw/day, based on decreased body weight and body weight gain in females, increased prothrombin time in males, increased alkaline phosphatase activity in both sexes, increased GGT levels in both sexes, increased liver weights in both sexes, increased hepatocellular hypertrophy in both sexes, and an increased incidence of thyroid follicular cell hypertrophy in both sexes.

870.4200 Carcinogenicity (rat) 48023815 (2009) Acceptable/guideline 0, 100, 2000 or 7000 ppm (diet) M: 0, 4.0, 79 and 288 mg/kg bw/day F: 0, 5.6, 113 or 399 mg/kg bw/day See above under 870.4100a. There are three tumor types (brain astrocytomas in males, ovarian tubulostromal neoplasms in females, and histiocytic sarcoma in males). Penflufen was evaluated by the EPA HED

Cancer Assessment Review Committee (CARC) on February 16, 2011, and it was concluded that penflufen should be classified Suggestive, quantification not required. All 3 tumor types were considered treatment-related. Dosing was considered adequate based on the presence of tumors.

870.4300 Carcinogenicity (mouse) 48023814 (2009)

0, 100, 1000, 6000 ppm M: 0, 14.3, 146, or 880 mg/kg bw/day F: 0, 18.4, 182, and 1101 mg/kg bw/day NOAEL = 6000 ppm (880/1101 mg/kg bw/day) LOAEL = LOAEL not identified (included a

dose level that exceeded the limit dose in

females and one that was close to the limit dose

in males.

The liver effects and associated effects on the thyroid are considered adaptive and not

adverse. no evidence of carcinogenicity

Gene

Mutation

870.5100 Ames assay

Salmonella typhimurium TA98, TA100, TA1535, Ta1537,

Ta1538 48023816 (2007) Acceptable/guideline 16 to 5000 μg/plate

BYF 14182 Negative with and without metabolic activation

Gene

Mutation

870.5100 Ames assay

Salmonella typhimurium TA98, TA100, TA1535, Ta1537,

Ta1538 48023817 (2009) Acceptable/guideline 3 to 5000 μg/plate

BYF 14182 Negative with and without metabolic activation

Page 44 of 106Penflufen Human Health Risk Assessment D387450

Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/ Results

Classification /Doses

Gene

Mutation

870.5100 Ames assay

Salmonella typhimurium TA98, TA100, TA1535, Ta1537,

Ta1538 48023818 (2008) Acceptable/guideline 16 to 5000 μg/plate Negative with and without metabolic activation

Gene

Mutation

870.5100 Ames assay

Salmonella typhimurium TA98, TA100, TA1535, Ta1537,

Ta1538 48023819 (2009) Acceptable/guideline 16 to 5000 μg/plateBYF 14182-pyrazolylAAP Negative with and without metabolic activation

870.5300 In vitro V79/HPRT

test – forward

mutation (BYF 14182) 48023820 (2007) Acceptable/guideline Experiment 1: without S9: 0, 25, 50, 75, 100, 125,

150 or 175 μ g/mL; with S9: 0, 50, 75, 100, 125, 150, 175 or 200 μ g/mL Experiment 2: without S9: 0, 12.5, 25, 50, 75, 100 or

125 μ g/mL; with S9: 0, 25, 50, 75, 100, 125 or

150 μ g/mL Negative with and without metabolic activation

870.5300 In vitro V79/HPRT

test – forward

mutation (BYF 14182) 48023821 (2009) Acceptable/guideline E1&E2: without S9: 0, 4.5, 9, 18, 27, or 36 μg/mL E1:with S9: 0, 4.7, 9.4, 18.8, 37.5, or 75 μg/mL E2: with S9: 0, 18.8, 37.5, 75, 100, or 125 μg/mL Negative with and without metabolic activation

870.5300 In vitro V79/HPRT

test – forward

mutation (BYF 14182-3- hydroxy-butyl) 48023822 (2008) Acceptable/guideline 0, 75, 150, 300, 600, 900, or 1200 μg/mL (+/-S9) Negative with and without metabolic activation

870.5300 In vitro V79/HPRT

test – forward

mutation (BYF 14182-3- pyrazolyl-AAP) 48023823 (2009) Acceptable/guideline 0, 3, 6, 12, 24, 36, 48, or

60 μ g/mL (+/-S9) Negative with and without metabolic activation

Page 45 of 106Penflufen Human Health Risk Assessment D387450

Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/ Results

Classification /Doses

870.5375 Chinese Hamster

V79 cells –

chromosome

aberrations (BYF 14182) 48023824 (2007) Acceptable/guideline 4-hour: 0, 10, 20, 40, 70, and 100 μg/mL (-S9) 18-hour: 0, 3, 6, 12, 24, 36 μg/mL (-S9) 4-hour: 0, 15, 30, 60 and 90 μg/mL (+ S9) 4-hour: 0, 40, 70, and 100 μg/mL (-S9) and 0, 60, 75, and 90 μg/mL (+S9) (harvested 30 hours after treatment) Negative with and without metabolic activation

870.5375 Chinese Hamster

V79 cells –

chromosome

aberrations (BYF 14182) 48023825 (2009)
Acceptable/guideline -S9: 0, 9.4, 18.8 and 37.5 g/mL (4-hour treatment) –S9: 0, 4.7, 9.4 and 18.8 μg/mL (18-hour treatment) +S9: 0, 18.8, 37.5 and 75.0 μg/mL (4-hour treatment) +S9: 0, 100, 150 and 300 μg/mL were harvested at

28 hours cytotoxicity determination

4.7-1200 μ g/mL (±S9)

2.3-300 μ g/mL (±S9). Negative with and without metabolic activation

870.5375 Chinese Hamster

V79 cells –

chromosome

aberrations (BYF 14182-3- hydroxy-butyl) 48023826 (2008) Acceptable/guideline -S9: 0, 150, 300, 600, 900, and 1200 μg/mL (4-hour treatment), and 0, 75, 150, 300, 450, and 600 μg/mL (18-hour treatment) +S9: 0, 75, 150, 300, 600, and 900 μg/mL (4-hour treatment); harvested

18 hours after treatment. 600, 900, and 1200 μg/mL (-S9) and 300, 600, and 900 μg/mL (+S9);

harvested 30 hours after treatment (4-hour treatment). Negative with and without metabolic activation

Page 46 of 106Penflufen Human Health Risk Assessment D387450

Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/ Results

Classification /Doses

870.5375 Chinese Hamster

V79 cells –

chromosome

aberrations (BYF 14182- pyrazolyl-AAP) 48023827 (2009) Acceptable/guideline -S9: 0, 15, 30 and 60 μg/mL (4-hour and 18- hour treatments) +S9: 0, 15, 30 and 60 μg/mL (18-hour harvest after treatment) Negative with and without metabolic activation

870.5395 Mouse

Micronucleus 48023828 (2007) Acceptable/guideline 250, 500, 1000 mg/kg (male) Negative

870.6200a Acute neurotoxicity screening battery 48023829 (2009) Acceptable/guideline (gavage) 0, 100, 500, or 2000 mg/kg bw NOAEL = 50 mg/kg/day LOAEL = 100 mg/kg/day based on decreased motor activity and locomotor activity in

females.

870.6200b Subchronic neurotoxicity screening battery 48023830 (2009) NOAEL = 2000 ppm (126/156 mg/kg bw/day LOAEL = 8000 ppm (516/609 mg/kg bw/day based on a slight decrease in motor activity in females, which is consistent with a similar finding of decreased motor activity in females in the acute neurotoxicity study.

870.6300 Developmental neurotoxicity Not required

870.7485 Metabolism and pharmacokinetics (species) 48023831

48023832

48023833

48023834

48023835

48023836 (2009) Single dose: elimination pharmacokinetics; rapid absorption & elimination; no apparent effect of increasing dose on absorption or elimination, although differences between

sexes in amount in feces/urine. Metabolism, single dose: most excreted in feces (males)/urine (females); widely distributed with highest concentration in liver and kidneys; biotransformation characterized as very fast; complex mixture of metabolites. Metabolic pathway, single dose: 94-97% excreted; numerous metabolites identified; almost complete absorption Multiple dosing: not performed

870.7600 Dermal penetration (rat, male) 48024009 (2009) Acceptable/guideline 1, 50, or 240 g/L for 8 hours (achieved doses ranged from 0.010 to 0.011 mg/cm 2 , 0.50 to 0.53 mg/cm 2 , and 2.63 to 2.73 mg/cm 2 ) maximum % absorbed was 1.442%, 4.152%, and 5.350% for high, mid, and low dose formulations, respectively

Page 47 of 106Penflufen Human Health Risk Assessment D387450

Page 48 of 106 Table A.2. Subchronic, Chronic and Oth er Toxicity Profile for Penflufen

Guideline

No. Study Type MRID No. (year)/

Classification /Doses Results

OECD

428 In vitro dermal absorption (human/rat) 48024011 (2009) Acceptable/non-guideline

Doses: 50 g/L, 10 g/L, and 1 g/L mean total amounts of [ 14 C] considered to be potentially absorbable ( directly absorbed + total remaining at dose site ) at doses of 50 g/L, 10 g/L, and 1 g/L were 4.115%, 5.754%, and 6.516%, respectively, for rat skin and 0.172%, 1.449%, and 1.457%, respectively, for human skin; mean % of the applied dose potentially absorbable was 24-fold, 4-fold, and 4.5-fold greater in the rat skin than in the human skin, respectively.

870.7800 Immunotoxicity 48023837 (2008) Acceptable/guideline 0, 200, 1000 or 7000 ppm M: 0, 17.9, 82.6 or 755.6 mg/kg bw/day F: 0, 20.4, 104.5 or 960.5 mg/kg bw/day NOAEL = 755.6 mg/kg bw/day for males and 960.5 mg/kg bw/day for females

LOAEL = not established

.Penflufen Human Health Risk AssessmentD387450A.3 Hazard Identification and Endpoint SelectionTable A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudyAcute Dietary, Allpopulations(including females13+)Acute Dietary,Females 13+Acute Neurotoxicity (rat)MRID 48023829Developmental Toxicity (rat)MRID 48023810The developmental toxicity studies in rats and rabbits and the acuteneurotoxicity study in rats were all considered for acute dietary riskassessment.Effects noted in the acute neurotoxicity study were attributed to a single doseand are appropriate for endpoint selection. The NOAEL and LOAELestablished are protective of any potential acute systemic or developmentaleffects.Selected. In the acute neurotoxicity studyin Wistar rats, decreased motoractivity and locomotor activity were observed in females on the day oftreatment at the LOAEL of 100 mg/kg (NOAEL = 50 mg/kg).No significant effects were observed in the developmental toxicity studies inrats (300 mg/kg/day) or rabbits (600 mg/kg/day) at the highest dose tested.Since neither study had toxic effects thatcould be attributed to a single doseexposure, neither is considered appropriate for endpoint selection/ or relevantfor the acute dietary risk assessment for females 13+. Both studies areclassified acceptable/non-guideline, since the highest dose tested in bothstudies is considered inadequate, basedon range-finding studies and the lack ofeffects in the definitive studies. However, the ACN study in rats can beselected for all populations since the NOAEL and LOAEL were lower than thehighest doses tested in the developmental toxicity studies. The ACN isconsidered protective of potential developmental effects, which might occur atadequately high dose levels.Not Selected: In the developmental toxicity study in Sprague-Dawley rats, thematernal findings at the 300 mg/kg/day dose level are considered minimal.Although there was a significant reduction in maternal body weight gain at 300mg/kg/day (↓13%), which correlated with a decrease in food consumption,body weights were comparable to thoseof the control, and the liver changesPage 49 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudyDevelopmental Toxicity (rabbit)MRID 48023811are considered adaptive and not adverse. A maternal toxicity lowest-observedadverse-effect-level (LOAEL) was not identified.No treatment-related effects were observed on litter parameters, including preand post implantation loss, early or lateresorptions, fetal death, percentage ofmale and female fetuses, fetal bodyweights, or on the incidence ofmalformations/variations at the external, visceral or skeletal fetal examination,at any dose level tested.Not selected: In the developmental toxicity study in rabbits, maternal findingsat the 600 mg/kg/day dose level are considered minimal. Although there was asignificant reduction in maternal body weight gain at 600 mg/kg/day (↓26%),which correlated with a decrease in food consumption, body weights werecomparable to those of the control. No other effects were observed. Amaternal toxicity lowest-observed-adverse-effect-level (LOAEL) was notidentified.No adverse effects were observed at 600 mg/kg/day, the highest dose tested.Minimal fetal rabbit toxicity was observed at this dose level, as evidenced bythe slight decrease in mean fetal body weights (7%-8%).Chronic Dietary,General PopulationChronic/Carcinogenicity (rat)MRID 48023815The chronic toxicity study in dogs, chronic toxicity study in rats, combinedchronic/carcinogenicity in rats, carcinogenicity study in mice, and the 2-generation reproduction study in rats wereall considered for chronic dietaryrisk assessment.Not selected: This study was not selected because there is no appropriateendpoint on which to regulate (LOAEL was not identified). The findings at7000 ppm (males: 288 mg/kg/day weight/day; females: 399 mg/kg bodyweight/day) included decreased body weight/body weight gain in females,increased liver weight in both sexes, increased incidence of centrilobular topanlobular hepatocellular hypertrophyand of centrilobular hepatocellularmacrovacuolation in both sexes, increased incidence of hepatocellular brownpigment in females, colloid alteration inthe thyroid in females, and increasedPage 50 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudyCarcinogenicity (mouse)MRID 48023814Chronic toxicity (dog)MRID 48023813cholesterol in females. These effectsare considered an adaptive response andnot adverse. Because of the presence of tumors, the dose levels are consideredadequate.Not selected: This study was not selected because there is no appropriateendpoint on which to regulate (LOAEL was not identified). The highest dosetested exceeded the limit dose in females and was close to the limit dose inmales. The liver effects and associatedeffects on the thyroid are consideredadaptive and not adverse. In the subchronic oral toxicity study in mice at asomewhat higher dose level (7000 ppm; males: 1238 mg/kg/day; females:1600 mg/kg/day), a similar liver response was observed, indicating thatcontinued exposure does not result in additional/more severe toxicity.Exposure of mice to BYF 14182 at dose levels greater than or near the limitdose for a period of 78 weeks did not result in an increase in the incidence ofany tumor type in either sex.CandidatesNOAEL = 32 mg/kg/day (males)/37.9 mg/kg/day (females), based on theminimal changes in the liver (increased liver weight and hepatocellularhypertrophy, which were not accompaniedby relevant changes in clinicalchemistry parameters and adverse liver lesions) that are not consideredadverse. The LOAEL = 357 mg/kg/day (males)/425 mg/kg/day (females),based on decreased terminal body weightand body weight gain (females),increased prothrombin time (males), increased alkaline phosphate activity(both sexes), decreased cholesterol (both sexes), increased GGT levels (bothsexes), decreased albumin and albumin/globulin ratio (both sexes), decreasedcalcium and phosphorus (both sexes), increased liver weights (both sexes),increased incidence of focal hepatocellular brown pigment and hepatocellularhypertrophy (both sexes), increased incidence of zona glomerulosa vacuolationof the adrenal gland (females), and an increased incidence of thyroid follicularcell hypertrophy (both sexes).Page 51 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/Study2-Generation Reproduction (rat)(adult)MRID 480238122-Generation Reproduction (rat)(offspring)MRID 48023812Subchronic Oral Toxicity (dog) MRID48023808Discussion: For the repeat dose studies(table at right), the dose spread is largein all cases, and the NOAELs aresimilar (males: 32-64 mkd/females: 38-76 mkd). In order not to breakBurnam’s law, the chronic dog studyprovides the only NOAEL that is lowerParental systemic NOAEL = 1000 ppm [64 mg/kg/day (males)/75.9 mg/kg/day(females)]. Parental LOAEL = 4000 ppm (252.2 mg/kg/day (males)/294.5mg/kg/day (females), based on decreased body weight, decreased body weightgain, alterations in food consumption, decreased thymus weight in bothgenders, and decreased spleen weights in females (both generations).Offspring NOAEL = 1000 ppm [58.4 mg/kg/day (males)/71.2 mg/kg/day(females)]. Offspring LOAEL = 4000 ppm (256.5 mg/kg/day (males)/293.4mg/kg/day (females), based on a slight decrease in litter size in bothgenerations, decreased pup body weightand pup body-weight gain, delayedvaginal patency and balanopreputial separation, and decreased brain, spleen,and thymus weights.NOAEL = 1800 ppm [55.7 mg/kg/day (males)/63.1 mg/kg/day (females)], theminimal liver effects (increased liver weight and hepatocellular hypertrophy),which were not accompanied by significantalterations in relevant clinicalchemistry parameters or adverse liver lesions, were observed. The effects areconsidered adaptive and not adverseover this time frame. LOAEL = 18000ppm (532 mg/kg/day (males)/568 mg/kg/day (females), decreased bodyweight/ body weight gain in females,increased alkaline phosphatase activity inboth sexes, increased GGT activity in bothsexes, decreased albumin in males,increased liver weights in both sexes,increased adrenal weights in males,increased incidence of hepatocellularhypertrophy in both sexes, and anincreased incidence of slight diffuse cortical hypertrophy/hyperplasia in theadrenal in males were observed.Comparison of NOAELs and LOAELsStudyNOAELLOAELEffectsAcuteAcuteneurotoxicity50100Decreased motor/locomotor activity infemalesRepeatReproduction(parental)♂64♀76♂252♀295↓BW/BWG/FC,↓thymus wt (♀/♂), spleenwt (♀)Page 52 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/Studythan the acute NOAEL. However,looking at the LOAELs, the magnitudeof the NOAEL for each repeat dosestudy could be the same.In the rat repeat oral dose studies atdose levels up to the limit dose, theeffects on the liver are consideredadaptive and not adverse. In the dogstudies, the duration of the studyrelative to the lifespan of the dog isshort. The selection is conservative butprotective of other findings and the lackof adequate studies to detect potentialdevelopmental effectsReproduction(offspring)♂58♀71♂257♀293↓little size both generations,↓pupBW/BWG, delayed sexual maturation(♀/♂),↓brain, spleen, thymus weightsSubchronic (dog)♂56♀63♂532♀568↓BW/BWG (♀),↑ALP (♀/♂),↑GGT(♀/♂),↓albumin (♂),↑liver weights(♀/♂),↑adrenal weights (♂),↑incidenceof hepatocellular hypertrophy (♀/♂), and↑incidence of slight diffuse corticalhypertrophy/ hyperplasia in the adrnal((♂).Chronic (dog)♂32♀38♂357♀425At NOAEL, minimal changes in liver(↑liver weight and hepatocellularhypertrophy, which were not accompaniedby relevant changes in clinical chemistryparameters or adverse liver lesions) thatare not considered adverse.At LOAEL,↓terminal BW/BWG (♀),↑prothrombin time (♂),↑ALP (♀/♂),↓cholesterol (♀/♂),↑GGT levels (♀/♂),↓albumin and albumin/globulin ratio (♀/♂),↓calcium and phosphorus (♀/♂),↑liverweights (♀/♂),↑incidence of focalhepatocellular brown pigment andhepatocellular hypertrophy (♀/♂),↑incidence of zona glomerulosa vacuolationof the adrenal gland (♀), and an↑incidence of thyroid follicular cellhypertrophy (♀/♂).Incidental Oral,Short-term (1-30days) andIntermediate-term (1– 6 months)2-Generation Reproduction (rats)(offspring)The reproduction study in rats, the 90-day oral toxicity study in dogs, the 90-day oral toxicity study in rats, the subchronic neurotoxicity study in rats wereall considered for incidental exposure risk assessment.No residential exposure is anticipated due to a proposed use for seed treatmentonly. Therefore, there is no potential for oral non-dietary (hand-to-mouth)ingestion exposure to infants and children.Offspring effects (population of concern)were noted in the reproduction studyin rats (delayed sexual maturation, both sexes), and the NOAEL = 1000 ppmPage 53 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudyMRID 48023812Subchronic Oral Toxicity (dog)MRID 48023808[58.4 mg/kg/day (males)/71.2 mg/kg/day (females)].NOAEL = 55.7 mg/kg/day (males)/63.1 mg/kg/day (females), the minimalliver effects (increased liver weightand hepatocellular hypertrophy), whichwere not accompanied by significant alterations in relevant clinical chemistryparameters or adverse liver lesions, were observed. The effects are consideredadaptive and not adverse over this time frame.The NOAELs are similar, and the LOAELs are lower than the highest dosestested in the developmental toxicity studies in rats and rabbits. Therefore, theselected endpoint is protective of effects that might be observed indevelopmental toxicity studies at adequate dose levels and is protective of anypotential developmental effects.Selected:90-day dog and 2-generation reproduction studies.In the reproduction toxicity study in rats, a slight decrease in litter size in bothgenerations, decreased pup body weightand pup body-weight gain, delayedvaginal patency and balanopreputial separation, and decreased brain, spleen,and thymus weights were observed at the LOAEL of 4000 ppm [(256.5mg/kg/day (males)/293.4 mg/kg/day (females)]. The NOAEL = 1000 ppm[58.4 mg/kg/day (males)/71.2 mg/kg/day (females)].In a subchronic oral toxicity study in dogs, decreased body weight/body weightgain in females, increased alkaline phosphatase activity in both sexes,increased GGT activity in both sexes, decreased albumin in males, increasedliver weights in both sexes, increased adrenal weights in males, increasedincidence of hepatocellular hypertrophy in both sexes, and an increasedincidence of slight diffuse cortical hypertrophy/hyperplasia in the adrenal inmales were observed at the LOAEL of 18000 ppm (532 mg/kg/day(males)/568 mg/kg/day (females). At the NOAEL 1800 ppm [55.7 mg/kg/day(males)/63.1 mg/kg/day (females)], the minimal liver effects (increased liverweight and hepatocellular hypertrophy), which were not accompanied bysignificant alterations in relevant clinicalchemistry parameters or adverse liverPage 54 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudySubchronic Neurotoxicity (rat)MRID 48023830lesions, were observed. The effects are considered adaptive and not adverseover this time frame.Not selected: A NOAEL for neurotoxicology endpoints is established at 2000ppm (126 mg/kg/day (males)/156 mg/kg/day (females). The LOAEL is 8000ppm [516 mg/kg/day (males)/609 mg/kg/day (females)], based on a slightdecrease in motor activity in females, which is consistent with a similar findingof decreased motor activity in females in the acute neurotoxicity study (MRID48023829).Dermal AbsorptionIn VivoRepeat Exposure Dermalpenetration (rat)MRID 48023809In VivoSingle 8-hour applicationDermal penetration (rat)MRID 48024009In VitroDermal Absorption (human andrat skin)MRID 48024009LOAEL was not identified. There was anincreased incidence of thymic debris(minimal severity) in both sexes at the limit dose [1000 mg/kg/day (7 of 10 inboth sexes)]. This lesion was characterized by the increased presence offragmented thymic cortical lymphocytes noted within tingible bodymacrophages. This finding was not accompanied by a decrease in the size orweight of the thymus or changes in lymphocyte counts. The significance of thefinding at the limit dose is not known.Following single 8-hour dermal application, the amount of [14C]-BYF 14182potentially absorbable (sum of direct absorption and amount detected in theskin) ranged from 0.775% and 1.442% for the neat product (240 g/L), from2.743% and 5.152% for the intermediate dose (50 g/L) from 4.004% and5.350% for the low dose (1 g/L) formulation.Direct dermal absorption seemed to increase over time and ranged from0.277% at 8 hours post dose to 0.960% at 168hours post dose (240 g/L), from1.584% at 8 hours post dose to 2.388% at 168 hours post dose (50 g/L), andfrom 1.624% at 8 hours post dose to 4.948% and 3.770% at 72 and 168 hourspost dose (1 g/L).For the Penflufen FS 240 red formulation (neat formulation, 50 g/L), the totalabsorbable dose at 24 hours post-dose was 23.9-fold greater for rat skin(4.115%) than human skin (0.172%). For a 10 g/L dilution of the Penflufenformulation, the total absorbable dose was 3.97-fold greater for rat skinPage 55 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudyEstimated humanin vivoDAF using theabove 2 studiesComparison of the 28 day oral toxicitystudy in rats (MRID 48023838) and the28-day dermal toxicity study in rats(MRIF 48023809)Structure Activity Relationship (SAR)andPhysiochemical properties(3.754%) than human skin (1.449%). For the 1 g/L dilution of the Penflufenformulation, the total absorbable dose was 4.47-fold greater for rat skin(6.516%) than human skin (1.457%).ParameterPenflufen (g/L)150Human/in vitro1.4570.172Rat/in vitro6.5164.115Rat/in vivo(24 hours)4.0042.898Estimated human/in vivo (24 hours)0.890.12For risk assessment purposes, an upper bound dermal absorption factor (DAF)can be calculated by comparing the 28-day oral and dermal studies in rats.However, no significant effects were observed at the highest dose tested ineither study.NOAEL (1000mg/kg/day) from a 28-day dermal toxicity study in rats (notoxic effects noted; thymic debris) and the HDT (560/648 mg/kg/day) from a28-day oral toxicity study in rats (adaptive liver effects noted). An estimatedDAF of 56% (DAF= (560/1000) x 100%=56%). The estimated DAF is at least10-fold higher than the highest DAF observed in rats (6.52%) after 24 hours incomparativein vitrodermal absorption studies (rat and human skin) and 5.35%followingin vivo8-hour exposure in the rat. Thein vitrostudies also indicatethat dermal absorption in rat skin wasat least four times higher (4-24X) thanabsorption in human skin (0.17-1.45%).No appropriate structure activity relationships were identified. In the absenceof chemical-specific or structural analog data, physiochemical properties of thetest material could be considered when determining an appropriate dermalabsorption factor. It has been traditionally accepted that 10% dermalabsorption may be assumed where the molecular weight is greater than 500Page 56 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/Study100% Dermal Absorption Factor (DAF)and log octane-water (Pow) is smallerthan -1 or higher than 4. Otherwise100% dermal absorption is used. The molecular weight for penflufen is 317.4(<500) and the Pow is 3.33 (less than 4). Therefore, a 10% DAF is notappropriate.A 100% default DAF is used when there are no other options for estimating aDAF, when there are no validin vivodermal absorption studies, or whenphysicochemical properties do not support reduction to less than a 100% DAF,and oral to dermal extrapolation isnot appropriate. The 100% DAF does notappear appropriate.DermalDermal toxicity (rat)MRID 48023809The repeat dose dermal toxicity studyin rats, the 2-generation reproductionstudy in rats, the 90-day oral toxicity study in dogs, chronic oral toxicity studyin dogs, the subchronic neurotoxicity study in rats were all considered forshort-and/or intermediate-term dermal risk assessment.In a 28 day dermal toxicity study inrats, no dermal irritation or systemiceffects were observed up to the limit dose of 1000 mg/kg/day (thymic debris).There are no adequate developmental toxicity studies with which to assessoffspring effects.The highest doses tested (300 and 600 mg/kg/day in the ratand rabbit, respectively) are greaterthan the NOAELs selected for acute andchronic oral exposure.Offspring effects were noted in the reproduction study in rats (delayed sexualmaturation, both sexes), and the NOAEL is 1000 ppm [58.4 mg/kg/day(males)/71.2 mg/kg/day (females)].In the dog studies at the NOAELs [55.7 mg/kg/day (males)/63.1 mg/kg/day(females) and 32 mg/kg/day (males)/37.9 mg/kg/day (females)], the minimalliver effects (increased liver weightand hepatocellular hypertrophy), whichwere not accompanied by significant alterations in relevant clinical chemistryparameters or adverse liver lesions, were observed. The effects are consideredadaptive and not adverse over both time frames.Page 57 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudyDermal,Short-term,(1-30 days)Dermal,Intermediate-term(1-6 months)2-Generation Reproduction (rats)(offspring)MRID 48023812Subchronic Oral Toxicity (dog)MRID 48023808Chronic toxicity (dog)MRID 48023813The NOAELs are similar, and the LOAELs are lower than the highest dosestested in the developmental toxicity studies in rats and rabbits. Therefore, theselected endpoint is protective of effects that might be observed indevelopmental toxicity studies at adequate dose levels and is protective of anypotential developmental effects.Selected:90-day and chronic dog and 2-generation reproduction studies.In the reproduction toxicity study in rats, a slight decrease in litter size in bothgenerations, decreased pup body weightand pup body-weight gain, delayedvaginal patency and balanopreputial separation, and decreased brain, spleen,and thymus weights were observed at the LOAEL of 4000 ppm [(256.5mg/kg/day (males)/293.4 mg/kg/day (females)]. The NOAEL = 1000 ppm[58.4 mg/kg/day (males)/71.2 mg/kg/day (females)].In a subchronic oral toxicity study in dogs, decreased body weight/body weightgain in females, increased alkaline phosphatase activity in both sexes,increased GGT activity in both sexes, decreased albumin in males, increasedliver weights in both sexes, increased adrenal weights in males, increasedincidence of hepatocellular hypertrophy in both sexes, and an increasedincidence of slight diffuse cortical hypertrophy/hyperplasia in the adrenal inmales were observed at the LOAEL of 18000 ppm (532 mg/kg/day(males)/568 mg/kg/day (females). At the NOAEL 1800 ppm [55.7 mg/kg/day(males)/63.1 mg/kg/day (females)], the minimal liver effects (increased liverweight and hepatocellular hypertrophy), which were not accompanied bysignificant alterations in relevant clinicalchemistry parameters or adverse liverlesions, were observed. The effects are considered adaptive and not adverseover this time frame.NOAEL = 32 mg/kg/day (males)/37.9 mg/kg/day (females), based on theminimal changes in the liver (increased liver weight and hepatocellularhypertrophy, which were not accompaniedby relevant changes in clinicalchemistry parameters and adverse liver lesions) that are not consideredadverse. The LOAEL = 357 mg/kg/day (males)/425 mg/kg/day (females),Page 58 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudySubchronic Neurotoxicity (rat)MRID 48023830based on decreased terminal body weightand body weight gain (females),increased prothrombin time (males), increased alkaline phosphate activity(both sexes), decreased cholesterol (both sexes), increased GGT levels (bothsexes), decreased albumin and albumin/globulin ratio (both sexes), decreasedcalcium and phosphorus (both sexes), increased liver weights (both sexes),increased incidence of focal hepatocellular brown pigment and hepatocellularhypertrophy (both sexes), increased incidence of zona glomerulosa vacuolationof the adrenal gland (females), and an increased incidence of thyroid follicularcell hypertrophy (both sexes).Not selected: A NOAEL for neurotoxicology endpoints is established at 2000ppm (126 mg/kg/day (males)/156 mg/kg/day (females). The LOAEL is 8000ppm [516 mg/kg/day (males)/609 mg/kg/day (females)], based on a slightdecrease in motor activity in females, which is consistent with a similar findingof decreased motor activity in females in the acute neurotoxicity study (MRID48023829).Inhalation2-Generation Reproduction (rats)(offspring)MRID 480238122-Generation Reproduction (rats)The 2-generation reproduction study in rats, the 90-day oral toxicity studies inrats and dogs, the chronic oral toxicity study in dogs, the subchronicneurotoxicity study in rats, and the chronic study in dogs were all consideredfor short-and/or intermediate-term inhalation risk assessment.No repeat exposure inhalation studies are available, so an oral study was usedfor risk assessment, with an assumed absorption factor of 100%.Offspring NOAEL = 1000 ppm [58.4 mg/kg/day (males)/71.2 mg/kg/day(females)]. Offspring LOAEL = 4000 ppm [(256.5 mg/kg/day (males)/293.4mg/kg/day (females)], based on a slight decrease in litter size in bothgenerations, decreased pup body weightand pup body-weight gain, delayedvaginal patency and balanopreputial separation, and decreased brain, spleen,and thymus weights.Parental systemic NOAEL = 1000 ppm [64 mg/kg/day (males)/75.9 mg/kg/dayPage 59 of 106Penflufen Human Health Risk AssessmentD387450Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudyInhalation, ShortTerm(1-30 days)Inhalation,Intermediate-Term(1-6 months)(adult)MRID 48023812Subchronic Oral Toxicity (dog)MRID 48023808Chronic toxicity (dog)MRID 48023813(females)]. Parental LOAEL = 4000 ppm (252.2 mg/kg/day (males)/294.5mg/kg/day (females), based on decreased body weight, decreased body weightgain, alterations in food consumption, decreased thymus weight in bothgenders, and decreased spleen weights in females (both generations).In a subchronic oral toxicity study in dogs, decreased body weight/body weightgain in females, increased alkaline phosphatase activity in both sexes,increased GGT activity in both sexes, decreased albumin in males, increasedliver weights in both sexes, increased adrenal weights in males, increasedincidence of hepatocellular hypertrophy in both sexes, and an increasedincidence of slight diffuse cortical hypertrophy/hyperplasia in the adrenal inmales were observed at the LOAEL of 18000 ppm (532 mg/kg/day(males)/568 mg/kg/day (females). At the NOAEL 1800 ppm [55.7 mg/kg/day(males)/63.1 mg/kg/day (females)], the minimal liver effects (increased liverweight and hepatocellular hypertrophy), which were not accompanied bysignificant alterations in relevant clinicalchemistry parameters or adverse liverlesions, were observed. The effects are considered adaptive and not adverseover this time frame.NOAEL = 32 mg/kg/day (males)/37.9 mg/kg/day (females), based on theminimal changes in the liver (increased liver weight and hepatocellularhypertrophy, which were not accompaniedby relevant changes in clinicalchemistry parameters and adverse liver lesions) that are not consideredadverse. The LOAEL = 357 mg/kg/day (males)/425 mg/kg/day (females),based on decreased terminal body weightand body weight gain (females),increased prothrombin time (males), increased alkaline phosphate activity(both sexes), decreased cholesterol (both sexes), increased GGT levels (bothsexes), decreased albumin and albumin/globulin ratio (both sexes), decreasedcalcium and phosphorus (both sexes), increased liver weights (both sexes),increased incidence of focal hepatocellular brown pigment and hepatocellularhypertrophy (both sexes), increased incidence of zona glomerulosa vacuolationof the adrenal gland (females), and an increased incidence of thyroid follicularcell hypertrophy (both sexes).Page 60 of 106Penflufen Human Health Risk AssessmentD387450Page 61 of 106Table A.3. Toxicology Endpoint Selection Worksheet: PenflufenExposure ScenarioStudy CandidatesRationale for Selection of Dose/Endpoint/StudySubchronic Neurotoxicity (rat)MRID 48023830Not selected: A NOAEL for neurotoxicology endpoints is established at 2000ppm (126 mg/kg/day (males)/156 mg/kg/day (females). The LOAEL is 8000ppm [516 mg/kg/day (males)/609 mg/kg/day (females)], based on a slightdecrease in motor activity in females, which is consistent with a similar findingof decreased motor activity in females in the acute neurotoxicity study (MRID48023829).Penflufen Human Health Risk Assessment D387450

A.3.1 Acute Reference Dose (aRfD) - General Po pulation, including infants, children, and females age 13-49 Study Selected: Acute Neurotoxicity Study in Rats

MRID No.: 48023829 Executive Summary : See Appendix A, Guideline [§ 870.6200] Dose and Endpoint for Risk Assessment: NOAEL = 50 mg/kg bw, based on decreased motor and locomotor activity (39-81% on day of treat ment) in females seen at LOAEL = 100 mg/kg

bw. Comments about Study/Endpoint/Uncertainty Factors: The study is appropriate for acute dietary exposure due to the route (oral) and duration (acute) of dosing. The effects are clearly adverse and result from a single exposure. The NOAEL and LOAEL established are protective of any potential acute systemic or developmenta l effects. Endpoints from the developmental rat and rabbit studies as well as the 2-generation reproduction study were not selected since there

were no effects seen that were attributable to a single expos ure. Therefore, the dose and endpoint from the ACN study were selected and are considered protective of potential acute toxicity for all populations (i .e., the general population, incl uding infants and children and females ages 13 to 49 years old) since the NOAE L/LOAEL from the ACN were lower than the highest dose tested in the deve lopmental toxicity studies

A.3.2 Chronic Reference Dose (cRfD) ` Study Selected: Chronic Toxicity Study in Dogs

MRID No .: 48023813 Executive Summary : See Appendix A, Guideline [§ 870.4100] Dose and Endpoint for Risk Assessment: NOAEL = 38 mg/kg bw/day based on decreased terminal body weight and body weight gain (fem ales), increased prothrombin time (males), increased alkaline phosphate activ ity (both sexes), decreased chol esterol (both sexes), increased GGT levels (both sexes), decreased albumin and albumin/globulin ratio (both sexes), decreased calcium and phosphorus (both sexes) , increased liver weights (bot h sexes), increased incidence of focal hepatocellular brown pigment and hepa tocellular hypertrophy (b oth sexes), increased incidence of zona glomerulosa vacuolation of the adrenal gland (females), and an increased incidence of thyroid follicular cell hypertrophy (both sexes)at the LOAEL = 357 mg/kg/day (males)/425 mg/kg/day (females). Comments about Study/Endpoint/Uncertainty Factors: The study is appropriate for chronic dietary exposure due to the route (oral) and duration (chronic) of dosing. This is a conservative endpoint. For the repeat dose studies available, the dose spread is large in all cases (LOAEL of 250-532 mg/kg/day), and the NOAELs are simila r (males: 32-64 mg/kg/day/females: 38-76 mg/kg/day). The chronic dog st udy provides the only NOAEL that is lower than the acute NOAEL. In the rat repeat dose studies at dose leve ls up to the limit dose, the effects on the liver are considered mostly adaptive. In the dog studies, the duration of the study relative to the lifespan of the dog is short. The selection is conservative but pr otective of other findings and the lack of adequate studies to dete ct potential developmental effects.

A.3.3 Dermal Exposure (Short-, Intermediate- and Long-Term) In a 28-day dermal toxicity study in rats, no derm al irritation or systemic effects were observed up to the limit dose of 1000 mg/kg/ day. Dermal absorption is minima l (<1%). This is a routespecific study that also assessed all of the endpoi nts used in the other exposure scenarios and

Page 62 of 106Penflufen Hum an Health Risk Assessment D387450

Page 63 of 106 durations of exposure (e.g. neurol ogical endpoints, thyr oid and liver histopat hology). In addition, no increased susceptibility was seen between offs pring and adult animals in the developmental toxicity studies in rats an d rabbits and in the 2-generation reproduction study in rats. Therefore, the quantification of dermal risk is not required since no hazard was identified.

A.3.4 Inhalation Exposure (Short-Term) Study Selected: Subchronic Toxicity Study in Dogs

MRID No.: 48023808 Executive Summary : See Appendix A, Guideline [§ 870.3150] Dose and Endpoint for Risk Assessment: NOAEL = 55.7 mg/kg/day (1800 ppm) in males, based on decreased body weight/ body weight gain in females, increased alkaline phosphatase activity in both sexes, increased GGT activity in both sexes, decreased albumin in males, increased liver weights in both se xes, increased adrenal weights in males, increased incidence of hepatocellular hypertrophy in both sexes, and an in creased incidence of sl ight diffuse cortical hypertrophy/hyperplasia in the adrenal in ma les seen at LOAEL = 18000 ppm (532 mg/kg/day (males)/568 mg/kg/day (females). Comments about Study/Endpoint/Uncertainty Factors: No inhalation st udies are available for penflufen; therefore, a 90-day oral toxici ty study in dogs was used for inhalation risk assessment. The selected endpoint is the most se nsitive endpoint for this duration of exposure. For the repeat dose studies available, the dose spread is large in a ll cases (LOAEL of 250-532 mg/kg/day), and the NOAELs are similar (males : 32-64 mg/kg/day/females: 38-76 mg/kg/day). The subchronic dog study is appropriate for this duration of exposure. In the rat repeat dose subchronic oral toxicity studies at dose levels up to the limit dos e, the effects on the liver are considered mostly adaptive. In the dog studies, the duration of the study relative to the lifespan of the dog is short; therefore, the liver effects are cons idered adverse in the dog.

A.3.4 Inhalation Exposu re (Intermediate-Term) Study Selected: Chronic Toxicity Study in Dogs

MRID No.: 48023813 Executive Summary : See Appendix A, Guideline [§ 870.4100] Dose and Endpoint for Risk Assessment: NOAEL = 38 mg/kg/day based on decreased terminal body weight and body weight gain (fem ales), increased prothrombin time (males), increased alkaline phosphate activ ity (both sexes), decreased chol esterol (both sexes), increased GGT levels (both sexes), decreased albumin and albumin/globulin ratio (both sexes), decreased calcium and phosphorus (both sexes) , increased liver weights (bot h sexes), increased incidence of focal hepatocellular brown pigment and hepa tocellular hypertrophy (b oth sexes), increased incidence of zona glomerulosa vacuolation of the adrenal gland (females), and an increased incidence of thyroid follicular cell hypertrophy (both sexes) seen at LOAEL = 357 mg/kg/day (males)/425 mg/kg/day (females). Comments about Study/Endpoint/Uncertainty Factors: No inhalation studies are available for penflufen; therefore, a chronic oral toxi city study in dogs was us ed for inhalation risk assessment. In the rat repeat dose oral toxici ty studies, the effects on the liver occur following exposure that includes most of the rats’ lifes pan. In the dog studies, the duration of the study relative to the lifespan of the dog is short. Therefore, the selected endpoint is the most sensitive endpoint and most sensitive species for this duration of exposure.Penflufen Hum an Health Risk Assessment D387450

Page 64 of 106 A.4 Executive Summaries

A.4.1 Subchronic Toxicity

870.3100 90-Day Oral Toxicity - Rat Executive Summary : In a subchronic oral toxi city study (MRID 48023805), BYF 14182 (batch number NLL 7306-18, 98.6% purity) was administered continuously via dietary administration to groups of Wi star rats (10/sex/group) at concentrations of 0, 150, 7000, or 14000 ppm (equivalent to 0, 9.5, 457 and 949 mg /kg bw/day in males and 0, 11.4, 492 and 1009 mg/kg bw/day in females) for at least 90 da ys. This study is a companion study to MRID 48023806 (SA 05148, M-273186-01-2), which is a 90-day di etary study in Wistar rats that was performed using dose levels of 0, 50, 150, or 3500 ppm (equivalent to 0, 3.2, 9.3 or 228 mg/kg bw/day in males and 0, 3.7, 11.4 or 260 mg/kg bw/day in females).

No treatment-related mortalities or clinical sign s of toxicity (includi ng the neurotoxicological assessment) were observed duri ng the study in either sex. Body weight was comparable among the male groups throughout the study, although body weight gain was significantly reduced by 24% in males at 14000 ppm during the first week of treatment. Thereafter, body weight changes were similar to controls. In females, body weight was slightly reduced ove r the entire treatment period (5% to 7%) at 7000 ppm and 14000 ppm. Duri ng the first week of treatment, body weight gain was reduced in females by 36% at 7000 ppm and 55% at 14000 ppm. With continued exposure, the weekly body weight gain was co mparable among the groups through 7 weeks. On Day 90, the overall mean reduction in body weight gain was 17% at 7000 ppm and 12% at 14000 ppm, when compared to controls, but there wa s no dose response. Mean food consumption was reduced over the entire treatment period at 7000 ppm (8% to 17%) and 14000 ppm (5% to 14%) compared to controls.

Higher total cholesterol concentration, globulin concentra tion, and gamma-glutamyltransferase activity and lower albumin/globulin ratio were observed in both sexes at 7000 ppm and 14000 ppm. Higher total protein concentration (7000 ppm and 14000 ppm) and albumin concentration (14000 ppm) were observed in males. Lower mean alanine aminotransfera se and/or asparate

aminotransferase activities were observed in bo th sexes at 14000 ppm. In females at 7000 ppm and 14000 ppm, lower total bilirubin concentrations were observed. At necropsy, mean absolute and relative liver weights were increased in males and females at 14000 ppm and to a lesser extent at 7000 ppm. Enlarged livers were observed in all rats at 14000 ppm and in 8/10 males and 7/10 females at 7000 ppm. Centrilobular hepatocellular hypertrophy was observe d in all rats of both sexes at 7000 ppm and in 9/10 males and all females at 14000 ppm, compared to none in either sex in the control and 150 ppm groups. In the thyroid, 8/10 males at both the 7000 ppm and 14000 ppm dose levels, and 6/10 females at 14000 ppm had thyroid follic ular cell hypertrophy, a nd 3/10 males at both the 7000 ppm and 14000 ppm dose levels had altere d colloid. In the ki dney, an increased incidence of hyaline droplet accumulation was noted in 6/10 males at 14000 ppm and in 5/10 males at 7000 ppm.

In this definitive 90-day rat study (MRID 48023805) , together with the findings of MRID 48023806 (point KIIA 5.3.2/02), it was concluded th at the Lowest Observ ed Adverse EffectPenflufen Hum an Health Risk Assessment D387450

Page 65 of 106 Level (LOAEL) was not identified. The findings at 14000 ppm (equivalent to 949 mg/kg bw/day in males and 1009 mg/kg bw/day in females) included an increase in total cholesterol concentration and gamma-glutamyltransferase activity in both sexes, an increase in the incidence of centrilobular hepatocellula r hypertrophy, which was correlated with higher liver weights and macroscopically enlarged livers in both sexes, an increased incidence of thyroid follicular cell hypertrophy in both sexes, and alte red colloid in males. These e ffects are considered an adaptive response and not adverse.

This study is classified as totally reliable (acce ptable/guideline), and it satisfies the guideline requirement for a subchronic oral toxici ty study (OPPTS 870.3100; OECD 408) in rats. Executive summary : In a subchronic oral toxi city study (MRID 48023806), BYF 14182 (batch number NLL 7306-18, 98.2 to 98.8% purity) was administered via the diet to groups of Wistar rats (10/sex/group) at concentrations of 0, 50, 150, and 3500 ppm (equivalent to 0, 3.2, 9.3 and 228 mg/kg bw/day in males and 0, 3.7, 11.4 and 260 mg/kg bw/day in females) for at least 90 days. In this study, only the kidney, liver, pancreas, pituitary and thyroid glands were examined at microscopy, and no hematology, urinal ysis, ophthalmological, or neurotoxicological examinations were performed. This study was pe rformed to provide additional information on the potential toxic effects of BY F 14182 observed in a similar subc hronic oral t oxicity study in Wistar rats (MRID 48023805). Both studies were pe rformed to provide information for selection

of dose levels for future t oxicity studies in the rat. No treatment-related mortalities or clinical sign s of toxicity were obs erved during the study. No treatment-related body weight or food consumpti on changes were observed at any dose level throughout the study. Clinical chemistr y parameters were not affected.

At necropsy, mean terminal body weight in females at 3500 ppm was decreased by 6% when compared to control rats. Mean absolute and re lative liver weights were increased by 13% to

15% in males and 8% to 16% in females. Enla rged livers were observed in 4/10 females at 3500

ppm. Increased liver weights were obs erved in both sexes at 3500 ppm, which is consistent with the minimal centrilobular hepatocellular hypertrophy observed in both sexes at 3500 ppm. This finding was considered to be an adaptative respon se and not an adverse effect, based on a lack of accompanying alterations in relevant clinical ch emistry parameters and adverse lesions. There was an increase in thyroid wei ght in both sexes, mainly at the3500 ppm dose level, but these changes were not accompanied by any microscopi c findings. In the kidney, minimal tubular hyaline droplets were observed in males at 3500 ppm.

A Lowest Observed Adverse Effect Level (LOAEL) was not identified in this study. At the highest dose tested (3500 ppm, equivalent to 228 mg/kg bw/day in males and 260 mg/kg bw/day in females), increased liver weights and an increased incidence of centrilobular hepatocellular hypertrophy were observed, whic h were not accompanied by alterations in relevant clinical chemistry parameters or adv erse liver lesions. The effects observed are considered adaptive and not adv erse over this time frame.

This subchronic oral toxicity study is classified acceptable/non-guideline and alone does not satisfy the guideline requirement for a subchroni c oral toxicity study in the rat. It is nonguideline because only the kidney, liver, pancreas, pituitary and t hyroid glands were examinedPenflufen Hum an Health Risk Assessment D387450

Page 66 of 106 microscopically, and hematology, urinalysis, or ophthalmological exam inations were not performed. When considered together with MRID 48023805 (Report No. SA04199), this guideline requirement (OPPTS 870. 3100; OECD 408) is satisfied.

870.3100 90-Day Oral Toxicity - Mouse Executive Summary : In a subchronic oral toxi city study (MRID 48023807), BYF 14182 (batch number NLL 7306-18, 98.8% purity) was administered continuously via dietary administration to groups of C57BL/6J mice (10/ sex/group) at concentr ations of 0, 150, 3500 and 7000 ppm (equivalent to 0, 26.9, 638 and 1238 mg/ kg bw/day in males and 0, 31.5, 757 and 1600 mg/kg bw/day in females) for at least 90 days.

No mortalities or treatment-re lated clinical signs of toxic ity were observed during the study. Body weight and food consumption parameters were comparable among the groups for both sexes throughout the study. There was a dose-related decrease in to tal cholesterol concentration in males and females at the 3500 ppm and 7000 pp m dose levels. Alanine aminotransferase was increased in both sexes at 7000 ppm (males ↑ 35%/females ↑ 48%), although statistical significance was not attained in the males. At necropsy, there was a dos e-related increase in mean absolute and relative liver weights in both sexes at 3500 ppm and 7000 ppm. Enlarged livers were observed in 9/10 males and 8/10 females at 7000 ppm and 5/10 males and 1/10 females at 3500 ppm. Consistent with these findings was

the increased incidence of mi nimal to mild diffuse centril obular hepatocellular hypertrophy

observed in 9/10 males and 7/10 females at 7000 ppm and 4/10 males a nd 4/10 females at 3500

ppm. A Lowest Observed Adverse Effect Level (LOA EL) was not identified in this study, which included a dose level that exceeded the limit dose in both sexes (7000 ppm; equivalent to 1238 mg/kg bw/day in males and 1600 mg/kg bw/day in females). The liver effects are considered adaptive and not adverse.

This subchronic oral toxicity study is classified acceptable/non-guideline, and it does not satisfy the guideline requirement (OPPTS 870.3100; OECD 408) for a subchronic oral toxicity study in the rodent. The study is consid ered non-guideline because there were no ophthalmoscopic or hematological examinations, ovaries were not weighed, and several clinical chemistry parameters (sodium, potassium, glucose, a nd creatinine levels) were not measured.

870.3150 90-Day Oral Toxicity – Dog

Executive Summary : In a subchronic oral toxi city study (MRID 48023807), BYF 14182 (batch number 2005-004498, 95.6% purity) was admi nistered to 4 Beagle dogs/sex/group via the diet at doses of 0, 180, 1800 or 18000 ppm (equi valent to 0, 5.6, 55.7 and 532 mg/kg bw/day in males and 0, 6.1, 63.1 and 568 mg/kg bw/day in females) for at least 13 weeks.

There were no mortalities or treatm ent-related clinical signs of toxi city or changes at the physical and ophthalmological examinations and urinalysis in either sex. Duri ng the first week of exposure, a mean body weight loss of 0.1 kg was obs erved in males at 1 8000 ppm compared to a mean body weight gain of 0.1 kg in controls. Thereafter, mean body weights in males at 18000Penflufen Hum an Health Risk Assessment D387450

Page 67 of 106 ppm were similar to controls. Over all body weight gain was reduced ( ↓ 25%) in males at 18000 ppm. In females at 18000 ppm, the mean body we ight gain was reduced by 50% during the first week of dosing, by 89% during weeks 1-7, and by 82% overall. Final body weights were reduced by ↓ 21% in females at 18000 ppm compared to the controls. The overall mean body weight gain in females at 18000 ppm was reduced by 82% in high dose females compared to the controls. Mean food consumption was reduced by 39% in ma les and 35% in females during the first week of treatment compared to controls. This initial decrease in food consumption was most likely attributable to adaptation to th e treated diet. Thereafter, mean food consumption in males was comparable to controls, whereas food intake was lower in females at 18000 ppm throughout the study. Both sexes at 18000 ppm displayed an increa se in prothrombin time throughout the study (compared to the pre-test and control values) at 18000 ppm. Increased platelet counts were observed in females and decreased total protein was observed in males at 18000 ppm. Increased alkaline phosphatase activity was observed in both sexes at 18000 ppm throughout the study, and the magnitude of the change increased with time on test. Gamma-glutamyltransferase activities were slightly increased in males and significan tly increased in females at 18000 ppm, and the magnitude of the change increased with time on test. Lower total cholesterol concentrations (relative to pre-test values) were observed in males throughout the study and in females at the end of the study at 18000 ppm. Mean albumin con centrations were decreased in both sexes at 18000 ppm throughout the study (relativ e to pre-test value), and th e albumin/globulin ratio was

decreased also.

There was a dose-related increase in adrenal weight in males, which was associated with a slight diffuse cortical hypertrophy/hyperp lasia in 2/4 males at 18000 pp m. There was a dose-related increase in liver weight in both sexes, which correlated with the microscopic lesions observed at 1800 ppm and 18000 ppm. A minimal to slight di ffuse panlobular hepatocellular hypertrophy was seen in all males and females at 18000 ppm, together with the multifocal presence of a minimal amount of intrahepatocellular eosinophilic material in 2/4 males and 1/4 females and minimal hepatocellular single cell death in 2/4 males and 1/4 females. At 1800 ppm, the liver changes were associated with a minimal diff use panlobular hepatocellu lar hypertrophy in 1/4

males and 3/4 females. A dietary level of 1800 ppm (equi valent to 55.7 mg/kg bw/day in males and 63.1 mg/kg bw/day in females) was established as the NOAEL in both sexes based on the minimal liver effects (increased liver weight and hepatocellular hypertrophy), which were not accompanied by significant alterations in relevant clinical chem istry parameters or adverse liver lesions. The effects observed are considered adaptive and not adverse over this time frame. The LOAEL is established at 18000 ppm (equivalent to 532 mg/ kg bw/day in males and 568 mg/kg bw/day in females), based on decreased body weight/body wei ght gain in females, increased alkaline phosphatase activity in both sexe s, increased GGT activ ity in both sexes, decreased albumin in males, increased liver weights in both sexes, increased adrenal weights in males, increased incidence of hepatocellu lar hypertrophy in both sexes, and an increased incidence of slight diffuse cortical hypertrophy/hyperpla sia in the adrenal in males.

This study is classified as tota lly reliable (acceptable/guideline), and it satisfies the guideline requirement for a subchronic oral toxici ty study (OPPTS 870.3150; OECD 409) in dogs.Penflufen Hum an Health Risk Assessment D387450

Page 68 of 106 870.3200 21/28-Day Dermal Toxicity – Rat

Executive Summary : In a subacute dermal toxicity study (MRID 48023809), Technical grade BYF 14182 (Batch No. 2005-004498; 95.6% purity) was administered by topical (dermal) application to 10 Wistar Hanover IG S [CRL:WI (Han)] rats/sex/dose at dose levels of 0 (control group), 100, 300, and 1000 mg/kg bw/day for 6 hours/ day, 5 days/week for 4 weeks, for a total of 21 doses. The test substance was applied to a 3-inch by 3-inch two-ply gauze pad that had

been moistened with deionized water.

There were no treatment-related deaths or cl inical signs of toxicity. Body weights, food consumption, hematology, clinical chemistry, orga n weights, and macroscopic examination of tissues were comparable among the groups for both sexes. There was an increased incidence of thymic debris (minimal severity) in both sexe s at 1000 mg/kg bw/day (7 of 10 in both sexes). This lesion was characterized by the increased presence of fragmented thymic cortical lymphocytes noted within tingible body macr ophages. This finding was not accompanied by a decrease in the size or weight of the thymus or changes in lymphocyte counts. The significance of the finding at the limit dose is not known. The No-Observed-Adverse-Effect Level (NOAEL) for dermal application over 28 days is established at 1000 mg/kg bw/day in males and females. A LOAEL was not identified. This dermal toxicity study is classified accep table/guideline, and it satisfies the guideline requirement (870.3200; OECD 410) for a repeat ed dose dermal toxicity study in rats.

870.3465 90-Day Inhalation – Rat

A.4.2 Prenatal Developmental Toxicity

870.3700a Prenatal Developmental Toxicity Study – Rat

Executive Summary : In a developmental toxici ty study (MRID 48023810), groups of sperm-positive female Sprague-Dawley rats (23/dose level) were exposed via oral gavage to BYF 14182 (batch number 2005-004498, 95.6% purity) at doses of 0 (vehicle , aqueous solution of 0.5% methylcellulose 400), 30, 100 or 300 mg/kg bw/day from gestation day (GD) 6 to GD

20.

There were no mortalities or treatment-related clin ical signs of toxicity in the maternal rats. Initially (GD 6-8), maternal rats at 300 mg/ kg bw/day displayed a mean body weight loss, and thereafter, gained weight at a lower rate than controls. Overall body wei ght gain (GD 6-21) at 300 mg/kg bw/day was 13% lower than control, and the corrected body weight gain was 19% lower than control. Body wei ght of the 300 mg/kg bw/day-dams on GD 21 was comparable to ( ↓ 3%) the control. Similarly at 100 mg/kg bw/d ay, maternal rats displayed lower mean body weight gains initially ( ↓ 32%) but the gains were comparable to control from GD 10 on. Maternal body weight of the 100 mg/kg bw/day-dams was s lightly greater than the control on GD 21, and maternal corrected body weight change was compar able to the control. Mean food consumption was reduced slightly at all intervals between GD 6 and 12 at 300 mg/kg bw/day. Thereafter, mean food consumption was unaffected by treatment.Penflufen Hum an Health Risk Assessment D387450

Page 69 of 106 At necropsy, treatment-related findings consiste d of prominent lobulati on of the liver in 4/23 females at 300 mg/kg bw/day and in 3/23 female s at 100 mg/kg bw/day. Mean liver weight was increased at 300 mg/kg/day ( 14%) compared to controls.

No treatment-related effects were observed on litter parameters, including pre and post implantation loss, early or late resorptions, fetal death, percentage of male and female fetuses, fetal body weights, or on the inci dence of malformations/variations at the external , visceral or skeletal fetal examination, at any dose level tested.

The maternal findings at the 300 mg/kg bw/d ay dose level are considered minimal. The dose levels do not appear adequate for asse ssing the developmental toxicity potential of BYF 14182. Although there was a si gnificant reduction in matern al body weight gain at 300 mg/kg bw/day, which correlated with a decrease in food consumption, body weights were comparable to those of the co ntrol, and the liver changes are considered adaptive and not adverse. A maternal toxicity lowest-obs erved-adverse-effect-level (LOAEL) was not

identified.

A developmental toxicity lowest-observed-adver se-effect-level (LOAEL) was not identified. At 300 mg/kg bw/day, the highest dose tested, no adverse effects were observed. However,

this dose was a no adverse effect dose level in the range-finding study also. The dose levels are not considered adequate for assessing th e developmental toxicity potential of BYF

14182.

This study is classified as acceptable/non-guideline, and it does not satisfy the guideline requirement (OPPTS 870.3700; OECD 414) for a devel opmental toxicity study in rats. It is nonguideline because dose levels were not adequate to assess developmental toxicity potential, but there is nothing to gain by repeating the study.

870.3700b Prenatal Developmenta l Toxicity Study – Rabbit

Executive Summary : In a developmental toxicity study (MRID 48023811), 23 time-mated pregnant female New Zealand White rabbits /dose level were administered BYF 14182 (batch number 2005-004498, 95.6% purity) via oral gavage from gesta tion day (GD) 6 to 28, the day of mating being designated GD 0. The doses given were 0 (vehicle, aqueous solution of 0.5% methylcellulose 400), 30, 100 and 600 mg/kg bw/day.

One female rabbit at 600 mg/kg bw/day was sacrificed for humane reasons on GD 25. This

rabbit had no or few feces between GD 17 and 25 and lost 640 g in body weight from GD 6 to 25. No abnormality was identified at necropsy. In the surviving dams, no treatment-related clinical signs were observed. The females at 600 mg/kg bw/day showed a mean body weight loss of 0.01 kg initially (GD 6 to GD 8) compared to a mean maternal body weight gain of 0.02 kg in the controls. Thereafter, mean mate rnal body weight gain was reduced ( ↓ 60% to ↓ 71%) at

several time intervals between GD 8 and 22 and overall (GD 6 to 29; ↓ 26%). All groups displayed a negative corrected body weight ch ange, but the mean ma ternal corrected body weight change at 600 ppm was larger (-0.29 kg) th an that of the control (-0.20 kg). Consistent with the reduced body weight gain, mean matern al food consumption was reduced at 600 mg/kgPenflufen Hum an Health Risk Assessment D387450

Page 70 of 106 bw/day (18% to 27%) throughout most of th e study (GD 6 to GD22). However, body weights were comparable among all groups

At sacrifice, no treatment-relate d macroscopic findings were observe d in the maternal rabbit, and mean liver weights were similar to the controls . Mean fetal body weights for the combined sexes and for the individual sexes at 600 mg/kg bw/day we re 7% to 8% lower than the controls. Other litter parameters were unaffected by treatment. There were no toxicologically rele vant external, visceral or sk eletal observations at any dose tested. However, a treatment-related increased in cidence of incomplete ossification of the 5 and 6 sternebrae was noted in the 600 mg/kg bw/day pups.

At the highest dose tested (600 mg/kg bw/day), minimal maternal toxi city was observed, as evidenced by the slight decrease (1%-4%) in body weight throughout the dosing period (GD 6- 29) and a lack of any other effects. Minimal feta l toxicity was observed at this dose level, as evidenced by the slight decrease in mean fetal body weights (7%-8%).

The maternal findings at the 600 mg/kg bw/d ay dose level are considered minimal. The dose levels do not appear adequate for asse ssing the developmental toxicity potential of BYF 14182 in the rabbit. Although there was a significant reduction in maternal body weight gain at 600 mg/kg bw/day, which correlate d with a decrease in food consumption, body weights were comparable to those of the control. No other effects were observed. A maternal toxicity lowest-observed-adverse-ef fect-level (LOAEL) wa s not identified.

A developmental toxicity lowest-observed-adver se-effect-level (LOAEL) was not identified. No adverse effects were observed at 600 mg/kg bw/day, the highest dose tested. However,

this dose was a no adverse effect dose level in the range-finding study also. The dose levels do not appear adequate for assessing the developmental toxicity potential of BYF 14182.

This study is classified as acceptable/non-guideline, and it does not satisfy the guideline requirement (OPPTS 870.3700; OECD 414) for a de velopmental toxicity study in rabbits. The study is classified as non-guideline because the highest dose is not considered adequate for assessment developmental toxicity. However, th ere is no need to repeat the study, as the endpoints selected (32-56 mg/kg bw/day) for risk assessment are protective of any effects that might occur at higher dose leve ls (>600 mg/kg bw/day).

A.4.3 Reproductive Toxicity

870.3800 Reproduction and Fertility Effects - Rat Executive Summary : In a two-generation reprod uction study (MRID 48023812), BYF 14182 (95.6%; Batch No. 2005-004498) was administered to 30 Wistar Han CRL: WI (HAN)

rats/sex/dose via the diet at nominal dietary conc entrations of 0, 200, 1000, or 4000 ppm [equivalent to 0, 12.8, 64.1, or 252.2 mg/kg bw/day (males)/ 0, 15, 75.9, or 294.5 mg/kg bw/day (females)] throughout the 10-week pre-mating pe riod and to the dams through gestation and

lactation. There was one set of litters per generation.Penflufen Hum an Health Risk Assessment D387450

Page 71 of 106 Parental rats : No treatment-related effects on survival or clinical signs of toxicity were observed in adult rats of either gender or generation. Reductions in body weight (males 5%-8%/females 7%-8%) and body weight gain (P1 males ↓ 14%/P1 females ↓ 36%/F1 adult female ↓ 15%) were accompanied by decreases in food consumption in both generations during the pre-mating periods at 4000 ppm. Throughout gestation, fe males showed declines in body weight ( ↓ 8%-10%) and body weight gain (days 0-20 14%-15%) in bot h generations at 4000 ppm. During lactation, females at 4000 ppm showed lower body weights ( ↓ 6%-11%) than the cont rols, but body-weight gains were slightly greater than the controls in both generations. Increased liver weights (absolute and relative) were observed in both genders and both generations at the 4000 ppm dose level and were accompanied by an increased in cidence of hypertrophy (c entrilobular and/or midzonal). These liver findings are considered an adaptive response and no t an adverse effect. Decreased thymus weight (absolute and rela tive) was observed in both genders in both generations at 4000 ppm, and decreased absolute sp leen weight was observed in females in both generations at 4000 ppm. These latter organ we ights were not accompanied by micropathology findings. The parental systemic LOAEL is 4000 ppm (252.2 mg /kg bw/day in males, 294.5 mg /kg bw/day in females), based on decreased body weight, decreased body weight gain, alterations in food consumption, decreased th ymus weight in both genders, and decreased spleen weights in females (both generation s). The parental systemic NOAEL is 1000 ppm (64 mg /kg bw/day in males and 75.9 mg /kg bw/day in females).

Offspring: Pups exhibited a decrease in body weight and a decrease in over all body weight gain throughout lactation at the 4000 ppm dose level. Litter size was decreased in both generations and was outside the historical control range. Ther e were delays in vaginal opening and preputial separation at the 4000 ppm dose level in both ge nerations. The magnitude of the associated decline in body weight was not considered to be a factor in the delay in female sexual

maturation. The time of occurrence of both landmarks was outside the testing facility's historical control range, but the one-day de lay in balanopreputial separation is not cons idered biologically significant. There was a decrease in absolute and relative spleen weights in both genders in both generations. Brain weight was slightly lower at 4000 ppm in both genders and both generations. The offspring LOAEL is 4000 ppm (256.5 mg/kg bw/day in males, 293.4 mg/kg bw/day in females). The LOAEL is based on a slight dec rease in litter size in both generations, decreased pup body weight and pup body-w eight gain, delayed vaginal patency, and decreased spleen weights. The offspring NOAEL is 1000 ppm (58.4 mg/kg bw/day in males, 71.2 mg /kg bw/day in females).

Reproductive Performance (P1 and F1): Reproductive toxicity wa s observed in both generations in females, as eviden ced by the delay in vaginal opening. The reproductive toxicity LOAEL is 4000 ppm (294.5 mg /kg bw/day), base d on delayed sexual maturation in females in both generations. The reproductive toxicity NOAEL is 1000 ppm (71.2 mg /kg bw/day).

This study is classified as tota lly reliable (acceptable/guideline), and it satisfies the guideline requirement for a 2-generation reproductiv e study (OPPTS 870.3800; OECD 416) in rats.Penflufen Hum an Health Risk Assessment D387450

Page 72 of 106 A.4.4 Chronic Toxicity

870.4100a (870.4300) Chronic Toxicity /Carcinogenicity – Rat

Executive Summary : In a chronic toxicity/carci nogenicity study (MRID 48023815), BYF 14182, (Batch N° 2005-004498, 95.6% pur ity) was administered via the diet to groups of Wistar rats at 0, 100, 2000 and 7000 ppm, corres ponding to 0, 4.0, 79 and 288 mg/kg bw/day in males and 0, 5.6, 113 and 399 mg/kg bw/day in females over a 24-month treatment period (10 rats/sex/group designated for the interim sacrifice after 52 week s, 10 rats/sex/group designated for the recovery group sacrificed af ter 65 weeks following 52 w eek of treated diet, and 13 weeks of untreated diet, and 60 rats/sex /group designated for the final sacrifice after 104 weeks).

No treatment-related mortality or clinical signs of toxicity were observed in either sex at any

dose level. Body weights and body weight gains were comparable among the male groups throughout the study. Treatment-related decreases in body weights and body weight gains were observed in females at 2000 pp m and 7000 ppm, and the body weight deficits increased with time of exposure. During the fi rst week of exposure, a dose -related reduction in body weight gain was observed in females at 2000 ppm ( ↓ 25%) and 7000 ppm ( ↓ 58%), whereas the reduction over the first 90 days was ↓ 10% and ↓ 20%, respectively. At study term ination, a 12% decrease in body weight was observed in females at 7000 ppm, and overall body weight gain was decreased by 18% compared to the control. Food consumpti on was consistent with the lower body weight observed. No differences on body we ight, body weight gain, or f ood consumption were observed at the end of the recovery period.

There was a dose-related increase in mean total cholesterol concentrations in females during the first year of treatment only, whereas treated male s displayed lower cholesterol values compared

to the controls but there wa s no dose-response. Decreases in alkaline phosphatase activity, aspartate aminotransferase activ ity, and alanine aminotransferase activity were observed in both sexes at 7000 ppm throughout the study.

At the end of the chronic phase (12 months), ther e was a dose-related increas e in liver weight in both sexes when compared to controls. In fe males at 2000 ppm and both sexes at 7000 ppm,

there was an increased incide nce of enlarged livers. At 7000 ppm, a higher incidence of centrilobular to panlobular he patocellular hypertrophy and centrilobular hepatocellular macrovacuolation was observed in both sexes, and a higher incidence of hepatocellular brown pigments was observed in females only. In the thyroid gland, a higher incidence of enlarged thyroid glands was observed at 7000 ppm, which co rrelated with a higher in cidence of follicular cell hypertrophy observed in both sexes and a higher incidence of colloid alteration was observed in females. The liver and the thyroid gland micros copic findings were mostly reversible as liver hypertrophy was not observed after the 3-month r ecovery period and only one male rat presented

a minimal follicular cell hypertrophy at the end of the recovery period.

At the end of the carcinogenicity phase (24 months), females at 7000 ppm showed increased thymus weights, although statistical significance was not attained. Both sexes at 7000 ppm displayed increased liver weight s (absolute and/or relative) co mpared to controls. Treatment-Penflufen Hum an Health Risk Assessment D387450

Page 73 of 106 related macroscopic findings consisted of enlarged livers and dark livers in the both sexes, white focus in the liver in females only, and dark thyroid glands in both sexes.

There was a dose-related increase in the incidenc e of centrilobular to pa nlobular hepatocellular hypertrophy and of centrilobular hepatocellular macrovacuolation in both sexes, and females displayed a higher incidence of hepatocellular brown pigments. In the thyroid gland, a higher incidence of follicular cell hypertrophy and collo id alteration was observed in both sexes. A higher incidence of follicular brown pigmen ts was observed in females at 7000 ppm.

There was evidence of an increase in the incide nce of neoplastic findings in both sexes. There was an increased incidence of brain astrocytomas in males at 7000 ppm, which are considered rare tumors. The increase in astrocytomas was marginal and not dose-related, and the increased incidence at the high dose did not reach statistical si gnificance when compared to controls. Additionally, there were no pre-ne oplastic lesions, such as glia l proliferation, which is a good

indicator of chemi cal tumor induction; i.e., there will be changes in the cells prior to transformation to a neoplasm. A higher incidenc e of ovarian tubulostromal neoplasms (adenoma and combined adenoma plus adenocarcinoma) was observed, The ovarian adenomas observed at the high dose also showed no dose response, no pair-wise significance, no decrease in latency,and there were no pre-neop lastic lesions such as hyperplasi a of the epithelial cells of the endometrium. Histiocytic sarcoma was observed in males at all dose levels compared to none in

the control males but there was an absence of a dose response and a lack of pre-neoplastic

lesions.

The NOAEL is 2000 ppm (males 79 mg/kg/day/ females 113 mg/kg/day). The LOAEL is 7000 ppm ( 288 mg/kg bw/day weight/day in males and 399 mg/kg bw/day in females), based on decreased body weight/body weight gain in fema les, increased liver we ight in both sexes, increased incidence of centrilobular to panl obular hepatocellular hypert rophy and centrilobular hepatocellular macrovacuolation in both sexes, increased incidence of hepatocellular brown pigment in females, hepatocellular necrosis, collo id alteration in the thyroid in females, and

increased cholesterol in females. This chronic toxicity/carcinogenic ity study is classified as accepta ble/guideline, and it satisfies the guideline requirement (OPPTS 870.4300; OECD 453) for a chronic toxicity/carcinogenicity study in the rat.

870.4100b Chronic Toxicity - Dog Executive Summary : In a one-year oral toxic ity study (MRID 48023813), BYF 14182 (batch number 2005-004498, 95.6% purity) was admi nistered to 4 Beagle dogs/sex/group via the diet at doses of 0, 200, 1000, or 10000 ppm (equivalent to 0, 6.8, 32.0 and 357 mg/kg body weight/day in males and 0, 7.7, 37.9 and 425 mg/kg body weight/day in females) for at least

52 weeks.

There were no mortalities, and no treatment-relate d clinical signs of toxicity or changes in ophthalmological examinations, hematology eval uation, or urinalysis were observed. t 10000 ppm, body weights and body weight gains were comparable among the male groups, but females showed lower body weights ( ↓ 18% at termination) and body weight gains ( ↓ 54% overall). Mean food consumption was reduced by 33% in high dose males and by 21% in high dose femalesPenflufen Hum an Health Risk Assessment D387450

Page 74 of 106 during the first week of treatment. This initial de crease was most likely attributable to adaptation to the treated diet. Thereafter, mean food consum ption was comparable to the controls in both

sexes. Prothrombin time was significantly increased in males at 10000 ppm. Mean alkaline phosphatase activities were markedly increased ( ↑ 215 to ↑ 389%, relative to pre-test values) in both sexes at 10000 ppm throughout the study. A sli ght increase in alkaline phosphatase activities was observed throughout the study in 1/4 males at 1000 ppm. In high dose dogs, mean albumin, albumin/globulin ratio, phosphorus, and calcium con centrations were decreased in both sexes relative to pre-test valu es and when compared to controls . GGT levels were increased at 10000 ppm in both sexes at termination compared to th e controls. Liver weights were increased in both sexes at all dose levels compared to controls. At necropsy, an en larged liver was observed in 1/4 males and a dark thyroid gland was observed in 1/4 males and 1/4 females at 10000 ppm. In the liver, panlobular hepatocellular hypertrophy was observed in 3/4 males and 4/4 females at 10000 ppm and in 1/4 females at 1000 ppm. Focal hepatocellular brown pigment was observed in 2/4 males and 3/4 females at 10000 ppm and 1/4 males at 1000 ppm. In the thyroid gland, minimal to slight follicular cell hypertrophy was observed in 1/4 males and 3/ 4 females at 10000 ppm. In the adrenal gland, an increased incidence of zona glomerulosa vacuolation was observed in females at 10000 ppm.

The No Observed Adverse Effect Level (NOAEL) is established at 1000 ppm (equivalent to 32 mg/kg body weight/day in males and 37.9 mg/kg body weight/day in females), based on the minimal changes in the liver (increased liver weight and hepatocellular hypertrophy, which were not accompanied by relevant change s in clinical chemistry parameters and adverse liver lesions)

that are not considered adverse. The Lowest Ob served Adverse Effect Level is established at 10000 ppm (equivalent to 357 mg/kg/day in male s and 425 mg/kg/day in females), based on decreased terminal body weight and body weight gain in females, increased prothrombin time in males, increased alkaline phosphate activity in both sexes, decreased chol esterol in both sexes, increased GGT levels in both sexes, decreased al bumin and albumin/globulin ratio in both sexes, decreased calcium and phosphorus in both sexes, in creased liver weights in both sexes, increased incidence of focal hepatocellular brown pigment and hepatocellular hypertrophy in both sexes, increased incidence of zona glomerulosa vacuolation of the adrenal gland in females, and an increased incidence of thyroid follic ular cell hypertrophy in both sexes.

This study is classified as tota lly reliable (acceptable/guideline), and it satisfies the guideline requirement for a chronic oral toxicity study (OPPTS 870.4100; OECD 452) in dogs.

A.4.5 Carcinogenicity

870.4200a Carcinogenicity Study – rat (see above)

870.4200b Carcinogenicity (feeding) – Mouse

Executive Summary : In a carcinogenicity study (M RID 48023814), BYF 14182 (Batch No. 2005-004498, 95.6% purity) was administered via the diet to C57BL/6J mice (60/sex/group) at dose levels of 0, 100, 1000 or 6000 ppm (equivalent to 0, 14.3, 146, and 880 mg/kg bw/day in males and 0, 18.4, 182, and 1101 mg/kg bw/day in females) for 52 weeks. After 52 weeksPenflufen Hum an Health Risk Assessment D387450

Page 75 of 106 (chronic phase), 10 mice/sex/group were sacrif iced (interim sacrifice). The remaining 50 mice/sex/group continued treatment until the scheduled final sacrifice following at least 78 weeks of treatment ( carcinogenicity phase).

There were no treatment-related effects on mortality or clinical signs of toxicity in either sex. Slight decreases ( ↓ 6%-7%) in overall body weight gains were observed in both sexes at 6000 ppm, but terminal body weights were comparable to the control for both sexes. Initial body weight gain was signi ficantly decreased ( ↓ 27%) in females at 6000 ppm, and males at 6000 ppm displayed a reduced body weight gain ( ↓ 18%) over the first 6 weeks.

There was a dose-related decrea se in mean total leukocyte ( ↓ 30% and ↓ 36%) and absolute lymphocyte ( ↓ 26% and ↓ 37%) counts in males at 1000 ppm and 6000 ppm, respectively, at 13 months. Females at 6000 ppm also showed decreases in mean total leukocyte ( ↓ 24%) and absolute lymphocyte ( ↓ 23%) counts at 13 months, but statistical significance was not attained.

At the 12-month sacrifice, increased liver weights were observed in both sexes at 6000 ppm compared to the controls. Enlarged liver was obs erved in 2/10 males and 6/9 females. Pale liver was observed in 1/10 males and 3/9 females. Histopathological examinations were not performed at this time point.

At the 18-month terminal sacrifice, increased ab solute and relative liver weights were observed in both sexes at 6000 ppm. Enlarged livers were observed in 2/45 males and 33/45 females. In addition, enlarged thyroid glands were found in9/45 females. These findings were correlated with treatment-related microscopic changes in th e liver and the thyroid gland. There was a doserelated increase in the incide nce and/or severity of diffu se centrilobular hepatocellular hypertrophy in both sexes. An increased incidenc e of hepatocellular vacu olation was observed in males at 6000 ppm, whereas a higher severity of hepatocellular vacuolation was observed in all female groups compared to the control. Additionally, females showed a higher incidence and severity of diffuse, mainly pe riportal, hepatocellu lar macrovacuolation at 6000 ppm. In the thyroid, a higher incidence and severity of fo llicular cell hyperplasia was observed in 38/50 females at 6000 ppm compared to 23 /50 females in the control group.

There was no increase in the incidence of a ny tumor type following dietary administration of

BYF 14182 to C57BL/6J mouse over an 18-mo nth period at dose levels up to 6000 ppm (equivalent to 880 and 1101 mg/kg body weight/day in males and females, respectively).

Treatment-related increased liver weights asso ciated with histopathol ogical findings were

observed in the liver in both se xes at all dose levels. These liver effects were associated with thyroid effects and are considered an adaptive response and not adverse.

A Lowest Observed Adverse Effect Level (LOA EL) was not identified in this study, which

included a dose level that exceeded the limit dose in females and one that was close to the limit

dose in males. The liver effects and associated effects on the thyroid are considered adaptive and

not adverse. In the subchronic oral toxicity study in mice at a somewhat higher dose level (7000 ppm; 1238 mg/kg bw/day and 1600 mg/kg bw/day), a similar liver response was observed, indicating that continued exposure does not result in additional/mo re severe toxicity. Exposure ofPenflufen Hum an Health Risk Assessment D387450

Page 76 of 106 mice to BYF 14182 at dose levels greater than or near the limit dose for a period of 78 weeks did

not result in an increase in the incidence of any tumor type in either sex.

This carcinogenicity study is classified accep table/guideline, and it sa tisfies the guideline requirement (870.4200; OECD 451) for a carci nogenicity study in the mouse.

A.4.6 Mutagenicity

Gene Mutation
Guideline 870.5100, Ames assay

MRID 48023816 Classification: acceptable/guideline BYF 14182 did not induce gene mutation, either with or without metabolic activation, in any of the S. typhimurium TA strains up to concentrations that inhibited cell growth in the plate incorporation and pre-incubation modification of the Salmonella/microsome test. Doses: 16 to 5000 μg/plate, diluted in dimethyl sulfoxide (DMSO). Growth

inhibition due to the test substance observed in all S. typhimurium TA

strains ±S9 at 1581 and 5000 μg per plate. Precipitation of the test

substance occurred at ≥ 500 μg per plate ±S9

.

Guideline 870.5100, Ames assay

MRID 48023817 Classification: acceptable/guideline BYF 14182 did not induce gene mutation, either with or without metabolic activation, in any of the Salmonella typhimurium TA strains atconcentrations up to 5000 μg/plate in the plate incorporation and in the preincubation modification of the S. typhimurium reverse mutation assay. Doses: 3 to 5000 μg/plate, diluted in dimethyl sulfoxide (DMSO).

Guideline 870.5100, Ames assay

MRID 48023818 Classification: acceptable/guideline BYF 14182-3-hydroxy-butyl did not induce gene mutation, either with or without metabolic activation, in any of the Salmonella typhimurium TA strains at concentrations up to 5000 μg/plate in the plate incorporation and in the pre-incubation modification of the S. typhimurium reverse mutation

assay. 8 concentrations ranging from 16 to 5000 μg/plate, diluted in dimethyl sulfoxide (DMSO).

Guideline 870.5100, Ames assay

MRID 48023819 Classification: acceptable/guideline BYF 14182-pyrozolyl-AAP did not induce gene mutation, either with or without metabolic activation, in any of the Salmonella typhimurium TA strains at concentrations up to 5000 μg/plate in the plate incorporation and in the pre-incubation modification of the S. typhimurium reverse mutation

assay. Doses: 6 concentrations ranging from 16 to 5000 μg/plate, diluted in dimethyl sulfoxide (DMSO).Penflufen Hum an Health Risk Assessment D387450

Page 77 of 106 Guideline 870.5300, mammalian cell forward gene mutation

MRID 48023820 Classification: acceptable/guideline Chinese hamster V79 cells: BYF 14182 did not induce increases in mutant frequency at concentrations up to 150 μg/mL (+S9)/100 μg/mL (- S9) in the V79/HPRT forward mutation assay. Significant concentration-related cytotoxicity was observed –S9 ( ≥ 125 μg/mL) and +S9 ( ≥ 150 μg/mL), as evidenced by decreases in survival to treatment and decreases in relative population growth following exposure. Doses: -S9: 0, 25, 50, 75, 100, 125, 150 or 175 μ g/mL (Experiment 1) and at 0, 12.5, 25, 50, 75, 100 or 125 μ g/mL (Experiment 2) ; +S9: 0, 50, 75, 100, 125, 150, 175 or 200 μ g/mL and 0, 25, 50, 75, 100, 125 or 150

μ g/mL for Experiments 1 and 2, respectively.

Guideline 870.5300, mammalian cell forward gene mutation

MRID 48023821 Classification: acceptable/guideline Chinese hamster V79 cells: Doses: 0, 4.5, 9, 18, 27, or 36 μg/mL (-S9) both Experiments 1 and 2, and at 0, 4.7, 9.4, 18.8, 37.5, or 75 μg/mL (+S9) Experiment 1 and 0, 18.8, 37.5, 75, 100, or 125 μg/mL +S9 in Experiment 2. The treatment period in both experiments was 4 hours. BYF 14182 did not induce increases in mutant frequency at concentrations up to 100 μg/mL (+S9)/36 μg/mL (- S9) in the V79/HPRT forward mutation assay.

Compound precipitation was noted at ≥ 100 μg/mL (+S9). BYF 14182 was tested up to cytotoxic concentra tions in the absence (36 μg/mL) and presence (100 μg/mL) of S9 activation. There were no reproducible

treatment-related increases in the mu tant frequency with or without metabolic activation at concentrations ranging from 4.5 μg/mL to 125 μg/mL.

Guideline 870.5300, mammalian cell forward gene mutation

MRID 48023822 Classification: acceptable/guideline Chinese hamster V79 cells: BYF 14182-3-hydroxy-butyl did not induce increases in mutant frequency (±S9), at concentration up to 1200 μg/mL (at or above the limit of solubility in the culture medium) in the V79/HPRT forward mutation assay. BYF 14182-3-hydroxy-butyl concentrations of 75, 150, 300, 600, 900, or 1200 μg/mL ±S9.

Guideline 870.5300, mammalian cell forward gene mutation

MRID 4802382 Classification: acceptable/guideline Chinese hamster V79 cells were ex posed to BYF 14182-pyrazolyl-AAP at concentrations of 0, 3, 6, 12, 24, 36, 48, or 60 g/ml both ±S9. BYF 14182- pyrazolyl-AAP did not induce increases in mutant frequency at concentrations up to 60 μg/mL (with and without metabolic activation) in the V79/HPRT forward mutation assay.Penflufen Hum an Health Risk Assessment D387450

Page 78 of 106 Cytogenetics

Guideline 870.5375 In vitro genotoxicity (clastogenicity in mammalian cells)

MRID 48023824 Classification: acceptable/guideline Chinese Hamster V79 cells: BYF 14182 did not induce increases in the numbers of aberrant metaphases at concentrations up to and including cytotoxic levels. Therefore, under the conditions of the study, BYF 14182 is considered not to be clastogenic for mammalian cells in vitro with and

without metabolic activation.

Doses: BYF 14182 at 0, 10, 20, 40, 70, and 100 g/mL (4-hour treatment) and 0, 3, 6, 12, 24, 36 μg/mL (18-hour treatment) –S9; at 0, 15, 30, 60 and 90 μg/mL (+ S9 mix; 4-hour treatment); harvested 18 hours after treatment start; cultures exposed (4-hour treatment) at 0, 40, 70, and 100 μg/mL (-S9) and 0, 60, 75, and 90 μg/mL (+S9) were harvested 30

hours

Guideline 870.5375 In vitro genotoxicity (clastogenicity in mammalian cells)

MRID 48023825 Classification: acceptable/guideline Chinese Hamster V79 cells: BYF 14182 did not induce chromosomal

aberrations in mammalian cells at co ncentrations that caused clear cytotoxicity (reduced cell numbers/mitotic indices below 50%/precipitation). BYF 14182 is not clastogenic for mammalian cells in

vitro

.

Doses: 0, 9.4, 18.8 and 37.5 g/mL (4-hour treatment, Experiment I), and 0, 4.7, 9.4 and 18.8 μg/mL (18-hour treatment, Experiment II) -S9 mix and at 0, 18.8, 37.5 and 75.0 μg/mL (+ S9 mix; 4-hour treatment, Experiment I); harvested 18 hours after treatment start; concentrations of 0, 100, 150 and 300 μg/mL (+S9 mix) were harvested at 28 hours after the beginning of treatment (Experiment II). The con centrations used for cytotoxicity determination ranged from 4.7-1200 μ g/mL for Experiment I (±S9) and

from 2.3-300 μ g/mL for Experiment II (±S9).

Guideline 870.5375 In vitro genotoxicity (clastogenicity in mammalian cells)

MRID 48023826 Classification: acceptable/guideline Chinese Hamster V79 cells: BYF 14182-hydroxy-butyl did not induce

increases in the numbers of aberrant metaphases at concentrations up to cytotoxic levels ( ≥ 900 μg/mL) in both the presence and absence of

metabolic activation. Doses of BYF 14182-3-hydroxy-butyl: 0, 150, 300, 600, 900, and 1200 g/mL (4-hour treatment), and 0, 75, 150, 300, 450, and 600 μg/mL (18- hour treatment) -S9 mix) and 0, 75, 150, 300, 600, and 900 μg/mL (4-hour treatment) +S9 mix. Harvested 18 hou rs after treatment start; cultures treated with 600, 900, and 1200 μg/mL (-S9) and 300, 600, and 900 μg/mL (+S9) were harvested 30 hours after the beginning of the treatment (4-hour treatment).Penflufen Hum an Health Risk Assessment D387450

Page 79 of 106 Guideline 870.5375 In vitro genotoxicity (clastogenicity in mammalian cells)

MRID 48023827 Classification: acceptable/guideline Chinese Hamster V79 cells: BYF 14182-pyrazolyl-AAP did not induce

increases in the numbers of aberrant metaphases at concentrations up to cytotoxic levels (60 μg/mL) in mammalian cells in vitro . Based on this test, BYF 14182-pyrazolyl-AAP is considered not to be clastogenic for

mammalian cells in vitro.

Doses of BYF 14182-pyrazolyl-AAP: 0, 15, 30 and 60 g/mL (4-hour and 18-hour treatments; -S9 mix) and at 0, 15, 30 and 60 μg/mL (+ S9 mix). Cultures harvested 18 hours afte r treatment start; cultures treated with 60 μg/mL were harveste d 30 hours after treatment.

Other Genotoxicity

Guideline 870.5395 In vivo genotoxicity (somatic cells) –

micronucleus

MRID 48023828 Classification: acceptable/guideline male Crl:NMRI BR mice were ad ministered BYF 14182 twice via the intraperitoneal (i.p.) route at doses of 0 (0.5% aqueous Cremophor emulsion), 250, 500 and 1000 mg/kg bw, separated by 24 hours. There was no indication of a clastogenic eff ect of intraperiton eally administered BYF 14182 in the micronucleus test on the male mouse at dose levels up to those producing clear evidence of an effect on the target population.

A.4.7 Neurotoxicity

870.6200 Acute Neurotoxicity Screening Battery Executive Summary : In an acute neurotoxicity study (MRID 48023829 ) , groups of non-fasted, >9-week old Wistar HAN CRL:WI (HAN) rats (12/sex/dose) were admini stered a single oral dose (gavage) of BYF 14182 (technical grade, 95.6%; Lot/Batch # 2005-004498) in 0.5% (w/v) methylcellulose/0.4% (w/v) Tween 80 in deio nized water (dosing volume of 10 ml/kg) at nominal doses of 0 (vehicle), 100, 500, or 2000 mg /kg bw and observed for 14 days. Since there were compound-related effects on measures of mo tor and locomotor activityat the low dose (100 mg/kg bw) in females, a follow-up study was c onducted with additional females (12/dose) under the same conditions at nominal doses of 0 (vehicle), 25, or 50 mg/kg bw.

In the initial study, all rats (12/ sex/dose level) were used for neurobehavioral evaluation, with 6/sex/dose used for micropathology. Observations for moribundity and mort ality were performed at least once daily for 14 days, detailed clinical observations for each animal were performed daily throughout the study and body weight measur ements (measured weekly as a component of the functional observational battery) were perf ormed. Neurobehavioral assessments (functional observational battery (FOB) and mo tor activity testing) were c onducted in the 12 rats/sex/group during the week prior to treatment and on days 0 (day of treatment, ≈ 1 hour post dose; the time of peak effect), 7 days (initi al group only) and 14 days (initial group only) post dose. At study termination, 6 rats/sex/group were euthanized and perfused for neuropathological examination. Of the perfused rats, all of the controls and 2000 mg/kg bw dose group were subjected to histopathological evalua tion of brain and peripheral nervous system tissues. All rats from the initial study were subjected to a gross necropsy. Sele cted rats (six/sex/dose level) were perfused, the brain was weighed, and skelet al muscle, peripheral nerves, ey es (with optic nerves), and tissues from the central nervous syst em were examined microscopically.Penflufen Hum an Health Risk Assessment D387450

Page 80 of 106 In the follow-up study, conducted to establish a NOAE L for measures of activity in females, the

rats were handled and otherwise treated the same as rats from the initial study for consistency; i.e., observations for moribundity and mortality were performed at least once daily, detailed clinical observations performed daily th roughout the study, and body weight measurements (component of the FOB). An FOB and automated measurements of activity (figure-eight maze) were conducted during the week prio r to treatment and on day 0 (day of treatment, at the time of peak effect). These rats were s acrificed when all signs of toxi city were no longer evident.

There were no deaths. On the day of treatment, clinical signs were observed at 500 mg/kg bw and 2000 mg/kg bw, which included urine stains in both sexes a nd an increased incidence of stiff-legged hind limbs, locomotor incoordination, decreased activity, and clear lacrimation in

females. A dose-related decrease in motor act ivity and locomotor activity was observed on the day of treatment in females at all dose levels and in males at 500 mg/kg bw and 2000 mg/kg bw. Habituation was not affected at any dose level in either sex. In the FOB, females at 500 mg/kg bw and 2000 mg/kg bw showed a similar decrease ( ↓ 0.8°C) in body temperature compared to the control. Body weights and body weight gains we re comparable among the groups (both sexes). All signs of toxicity resolved by day 7. Brain weight was not affected. There were no compoundrelated gross or microscopic lesions at 2000 mg/kg bw. The follow-up study established a

NOAEL for measures of motor and locomotor act ivity in females, with no compound-related effects at 25 mg/kg bw and 50 mg/kg bw.

The NOAEL in females is established at 50 mg/ kg bw. The LOAEL is established at 100 mg/kg bw, based on decreased motor activity and locomo tor activity in females. The NOAEL in males is established at 100 mg/kg bw. The LOAEL is established at 500 mg/kg bw, based on decreased motor activity and locomotor activity in females and urine staining.

This acute neurotoxicity study is classified as acceptable/guidelin e, and it satisfies the guideline requirement (OPPTS 870.6200; OECD 424) for an acute neurotoxicity study in rats.

870.6200 Subchronic Neurotoxicity Screening Battery

Executive Summary : In a subchronic neur otoxicity study (MRID 48023830), technical grade BYF 14182 (Lot/Batch # 2005-004498, 95.6%) was admi nistered in the diet to young-adult Wistar Han Crl:WI (HAN) rats ( 11-12/sex/dietary level), using no minal concentrations of 0, 250, 2000 and 8000 ppm (equivalent to 16, 126, and 516 mg/kg bw/day in males and 19.9, 155.9, and 608.8 mg/kg bw/day in females).

There were no deaths or clinical signs of toxicity in either se x at any dose level. Decreased body weights (males 6%-7%/females 5%-11%) and body weight gains (males 11%/females 29%) were observed in both sexes at 8000 ppm and were accompanied by decreased food consumption. There were no consistent findings during the FOB (other than bodyweight effects), and no treatment-related neuropath ological lesions were observed in either sex that could be

attributed to treatment. Motor activity was slightly reduced in females at 8000 ppm, which is consistent with the findings following acute exposure.Penflufen Hum an Health Risk Assessment D387450

Page 81 of 106 A NOAEL for neurotoxicology endp oints is established at 2000 ppm (equivalent to 126 mg/kg bw/day in males and 156 mg/kg bw/day in fe males). The LOAEL is 8000 ppm (equivalent to 516 mg/kg bw/day in males and 609 mg/kg bw/day in females), based on a slight decrease in motor activity in females, which is consistent with a similar finding of decreased motor activity in females in the acute neurotoxicity study (MRID 48023829).

This subchronic neurotoxicity study is classifi ed acceptable/guideline, and it satisfies the guideline requirement (OPPTS 870. 6200; OECD 424) for a subchroni c neurotoxicity study in the

rat.

A.4.8 Metabolism

870.7485 Metabolism - Rat Executive Summary : In a rat metabolism study (MRID 48023831), four male Wistar Unilever Hsd/Cpb:WU rats were gavaged with a single oral dose of [phenyl-UL- 13 C 6 / 14 C] BYF 14182 [batch nos. BECH 2034, 2137, 2155; 98%-99.5%] in 0.5% aqueous Tragacanth solution at doses of 2 mg/kg bw or 200 mg/kg bw. Four female Wistar Unilever Hsd/Cpb:WU rats were dosed only at the 2 mg/kg bw dose level. All rats we re sacrificed at 72 hour s after dosing to obtain blood, organs and tissues. Additionally, in a bile-duct cannulation experiment, 4 male rats were gavaged with a single dose of [phenyl-UL- 13 C 6 / 14 C] BYF 14182 at 2 mg/kg bw and were sacrificed at 48 hours after dosing. For analysis and quantification of the parent compound and metabolites in urine, bile, and faeces, respective sa mples from all rats in each test group were pooled, and samples from these pools were us ed for characterizati on, identification, and quantification. Urine, faeces, a nd bile samples were analyzed and quantified by radio-HPLC. In all four experiments, 94% to 97% of the admi nistered dose was recovered in urine, bile, and faeces, organs, and tissues at sacrif ice. The absorption of [phenyl-UL- 13 C 6 / 14 C] BYF 14182 commenced immediately after oral administration, with the maximum equivalent concentration (C

max ) in plasma being reached between 40 minutes and 1.5 hours (t

max ) after dosing [Test 1 (male): Peak reached at 40 minutes (0.7380 μg/m L), Test 2 (female): peak reached at 1.0 hour (0.7508 μg/mL), and Test 3 (male): Peak reach ed at 1.5 hours (19.190 μg/mL)]. The percent absorption of [phenyl-UL- 13 C 6 / 14 C] BYF 14182 based on recoveries of radioactivity in the bile, urine and body, excluding GIT, was 91.23% of the administered dose.

In males at both dose levels, the majority of the dose (> 61%) was excreted via faeces. The renal

excretion of male rats was ≈ 28% at 2 mg/kg, ≈ 34% at 200 mg/kg, and ≈ 21% in the bile duct cannulated male rats at 2 mg/kg. For the females, there was no significant difference between the

excretion via urine and faeces (both ≈ 46% of the dose) at 2 mg/ kg. Bile duct cannulated male rats showed a high excretion via bile ( ≈ 72% of the recovered radioa ctivity), and there was no significant radioactivity pres ent in the body at the time of sacrifice (48 hours after administration).

The radioactivity concentration in the plasma declined to ≈ 1% of the maximum value for both sexes at 2 mg/kg bw and to ≈ 3.6% for males at 200 mg/ kg bw within 72 hours post administration. The plasma concentration curves at the 2 mg/kg bw dose level showed a fast elimination phase at the begi nning of the test, and the t 1/2 elim 1 was 23.6 hours for males and 20.4

hours for females. Plasma concentrations of bot h sexes at 2 mg/kg bw showed one terminalPenflufen Hum an Health Risk Assessment D387450

Page 82 of 106 elimination phase. The plasma concentration curve of the 200 mg/kg bw group exhibited a second maximum after 48 hours possibly due to enterohepati c circulation.

At 2 mg/kg bw, the elimination of the test subs tance was somewhat faster for males than for

females. The AUC 0 - ∞ -value for females (3.6 mg/L-hour) is approximately 1.4 times higher than for males (2.5 mg/L-hour). This indicates a slig htly higher systemic exposure for female rats. The mean residence time (MRT tot ) of the radioactivity was short at 2 mg/kg bw (13.5 hours for males and 14.2 hours for females). Low amounts of ra dioactivity were determined in organs and tissues at sacrifice, 72 h after oral administration. Negligible amounts of radioactivity were found in the GIT, demonstrating an almost complete elimination of the radioactivity. Generally, concentrations in organs at 200 mg/kg bw were ≈ 100-times higher as compared to the concentrations at 2 mg/kg bw, reflecting the dos e ratio. The highest equivalent concentrations were detected in the liver (0.02 to 0.06 μg/g at 2 mg/kg bw and ≈ 6.15 μg/g at 200 mg/kg bw) and kidney ( ≈ 0.02 μg/g at 2 mg/kg bw and ≈ 3.14 μg/g at 200 mg/kg bw). Concentrations between 0.04 μg/g (at 2 mg/kg bw) and 6.74 μg/g (at 200 mg/kg bw) were found in erythrocytes. Residues were very low (in the range of 0.001 to 0.011 μg/g) in the other organs of both sexes at 2 mg/kg bw. In most cases, residues in the organs a nd tissues of female rats were slightly higher

than in male rats.

[Phenyl-UL- 13 C 6 / 14 C] BYF 14182 was extensively metabolized in the rat. Metabolic reactions were detected in 10 different positions of the mo lecule. By combination of the transformations at multiple sites, a large number of metabolites (up to 38 metabolites) were formed. The majority of metabolites (62.7% and 79.4% of the administered dose) were identified. The other metabolites were characterized by their extraction and chro matographic behavior. Th ere were no different metabolites found in males and females, but the am ount of some metabolites was different with regard to sex (e.g., BYF 14182-de smethyl-dihydroxy-ketone: males ≈ 5%/females 17% of the administered dose).

The most important metabolic reactions are the demethylation in the pyrazole ring and hydroxylation followed by further oxidation in di fferent positions of the molecule. BYF 14182- 3-hydroxy-butyl is a prominent metabolite in plants , and this metabolite and its conjugate were identified in very low amounts only in the bile in the current study. A separate rat ADME study with BYF 14182-3-hydroxy-butyl (MRID 48023836) as the test co mpound was performed (KIIA 5.1/06).

An overview of the main meta bolic reactions of [phenyl-UL- 13 C 6 / 14 C] BYF 14182 in rats is presented below: N-demethylation in the pyrazole ring hydroxylation at the following positions of the molecule: in the alkyl side chain of the phenyl ring, the position 4’ of the phenyl ring and the methyl group in position 3 of the pyrazole ring further oxidation of the hydroxy group in the positi on 2 of the alkyl side chain forming a keto

group further oxidation of the hydroxy group in the po sition 4 of the alkyl side chain forming a carboxylic acid oxidative cleavages of the alkyl side chain fo rming an acetyl group or a carboxylic acid groupPenflufen Hum an Health Risk Assessment D387450

Page 83 of 106 conjugation of the hydroxy group in th e position 4’ of the phenyl ring and in the position 2 of the alkyl side chain w ith glucuronic acid further oxidation of the hydroxymethyl group of the pyrazole ring forming a carboxylic acid

group conjugation of a dihydroxy, trihydroxy and dihydroxy-keto compound with cysteine

All results correspond well with the findings in the ADME study with the pyrazole label (IIA 5.1. 02). This metabolism study in the rat is classified acc eptable/guideline, and it satisfies the guideline requirement for a metabolism study [OPPTS 870.7485, OECD 417] in rats when considered in conjunction with the metabolism study in rats (MRID 48023832) using the [pyrazole-3- 14 C]

labeled BYF 14182.

Executive Summary: In a rat metabolism study (MRID 48023832), four male Wistar Unilever Hsd/Cpb:WU rats were administered ( via gavage) a single dose of [Pyrazole-3- 14 C] BYF 14182 [batch no. BECH 2136; 99% purity; radiochemi cal purity >98%] in 0.5% aqueous Tragacanth solution at a dose of 2 mg/kg bw a nd sacrificed 3 days after dosing. Plasma, urine and faeces were monitored throughout the st udy. The total radioac tivity was determined in plasma, urine, and faeces and in organs and tissues at sacrifi ce. The metabolism was inve stigated by HPLC with radioactivity detection and spectroscopic methods in selected urine samples and faeces extracts. At sacrifice, 94.6% of the administered radioac tivity was recovered in plasma, urine, faeces and in organs and tissues. The absorption of [pyrazole-3- 14 C] BYF 14182 started immediatel y after administration as shown by the plasma concentration curve. The renal excretion was 27.61% of the administered dose. The majority of the radioactivity (66.59% of administered dose) was excreted with the

faeces. The maximum equivalent concentration in plasma (C

max ) was 0.59μg/mL. The maximum (t

max ) was reached approximately 0.67 hour after dosing. Th e radioactivity in the plasma declined to

≈ 0.5% of the maximum concentration (C

max ) within 72 hours post dose. The plasma concentration curve showed a very fast elimination phase at the beginning of the test (= t 1/2 elim 1 ) followed by a single terminal eliminati on phase. Elimination half-lives were calculated based on a two-compartment model. The calculated AUC 0 - ∞ - was 2.4 mg/L * hour. A mean residence time (MRT tot ) of the total radioactivity wa s determined to be 13 hours. Low amounts of radioactivity were determined in organs and tissues at sacrifice 72 hours after oral administration. Negligible amounts of radioactivity were found in the GIT. The highest equivalent concentr ation was detected in liver ( ≈ 0.044 μg/g). Lower concentrations were detected in erythrocytes ( ≈ 0.037 μg/g), thyroid gland ( ≈ 0.019 μg/g), and in kidneys ( ≈ 0.017 μg/g). The concentrations in the other organs and tissues ranged from ≈ 0.002 to 0.007μg/g. [Pyrazole-3- 14 C] BYF 14182 was extensively metabolize d, and the majority of metabolites (68.7 % of the administered dose) were identified. Other metabolites ( ≈ 20.1% of the administered dose) were characterized. Most of the metabol ites were demethylated in the pyrazole ring. Hydroxylation was another prom inent metabolic reaction.

The main metabolic transf ormations detected were:

N-demethylation in the pyrazole ringPenflufen Hum an Health Risk Assessment D387450

Page 84 of 106 hydroxylation at the following posit ions of the molecule: the alkyl side chain of the phenyl ring, the position 4’ of the phenyl ring, and the methyl group in position 3 of the pyrazole ring further oxidation of the hydroxy group in the positi on 2 of the alkyl side chain forming a keto

group further oxidation of the hydroxy group in the po sition 4 of the alkyl side chain forming a carboxylic acid oxidative cleavages of the alkyl side chain fo rming an acetyl group or a carboxylic acid group conjugation of the hydroxy group in th e position 4’ of the phenyl ring and in the position 2 of the alkyl side chain w ith glucuronic acid further oxidation of the hydroxymethyl group of the pyrazole ring forming a carboxylic acid

group conjugation of a trihydroxy compound with cysteine cleavage of the carboxamide bond forming carboxylic acid, which was further metabolized via conjugation with glucuronic acid cleavage of the N-phenyl bond forming the carboxamide

The results in this ADME study with the pyrazole label are in good agreemen t with the results of the ADME study conducted with the phenyl label (IIA 5.1 /01) and with the results of the whole body autoradiography studies performed with BYF 14182 (IIA 5.1/03 and IIA 5.1/04). The main metabolic routes observed in the studies employing the phenyl and the pyrazole labels are identical, except for a few that are speci fic for the pyrazole label metabolites. This metabolism study in the rat is classified acc eptable/guideline, and it satisfies the guideline requirement for a metabolism study [OPPTS 870.7485, OECD 417] in rats when considered in conjunction with the metabolism st udy in rats (MRID 48023831) using the [ phenyl-UL- 13 C 6 / 14 C]

labeled BYF 14182.

Executive Summary: In a metabolism study (MRID 48023833), Wistar Hsd/Cpb:WU rats (8 males and 9 females) were administered ( via gavage) a single dose of [phenyl-UL- 13 C 6 / 14 C] BYF 14182 [batch no. NLL7306-16 and NLL7306-17, 99% purity; radiochemical batch no. BECH 1682 and BECH 2137, purity 98%-99%] in 0.5% aqueous Tragacanth solution at a dose level of 3.7 mg/kg bw (males) or 5.1 mg/kg bw (females). The distribution of the total radioactivity to and elimination from the blood, organs and tissues were analyzed qualitati vely and quantitatively by whole-body autoradioluminogr aphy (WBAL). The kinetic beha vior of BYF 14182, uniformly

labeled with 14 C and 13 C in the phenyl ring of the molecule , was investigated over a period of seven days. One rat/sex was sacrificed at 1, 4, 8, 24, 48 (female only), 72, 120, and 168 hours after dose for cryosectioning. The amounts of radio activity in the excreta (urine and faeces) and

exhaled air were determined also. BYF 14182 was readily absorbed from the gastro intestinal tract and quickly distributed throughout the body. The excre tion of radioactivity via urine and faeces was almost complete after 2 (females) to 3 (males) da ys. During the test period of 7 da ys, male rats showed a higher faecal (up to ≈ 68%) than urinary (up to ≈ 33%) excretion, and female rats showed a higher urinary excretion (up to ≈ 61%) than faecal (up to ≈ 41%) excretion. Less than 0.1% of the administered radioactivity was exhaled as 14 CO 2 or other volatiles dur ing a sampling period of 48 hours (both sexes).

In male rats, maximum total radioactiv e residues (TRR) values were reached for all organs and tissues (except nasal mucosa) at one hour after administration (t

max ). The values for liver, kidney,Penflufen Hum an Health Risk Assessment D387450

Page 85 of 106 myocardium and adrenals were higher than in the blood. A similar distribution was observed throughout the experimental period.

In female rats, maximum TRR-values were also reached for all organs and tissues at one hour after administration. The values for liver, ki dney, brown fat, myocar dium, pancreas, most glandular organs, and the ovary and uterus were higher than in blood. From peak values, a biphasic dec line of radioactivity concentrati ons was observed for all organs and tissues over the 7-day period. At terminati on, very low but still qua ntifiable radioactive residues (<0.05 μg active s ubstance-equiv./g) were measured in some organs. This metabolism study in the rat is classified acceptable/guideline and it satisfies the guideline requirement for a metabolism study [OPPTS 870.7485, OECD 417] in rats when considered in conjunction with the ADME metabolism studies in rats (MRID 48023831 using the [phenyl-UL13C6/14C] labeled BYF 14182 and MRID 48023832 us ing the [pyrazole-3-14C] labeled BYF

14182.

Executive Summary: In a metabolism study (MRID 48023834), Wistar Hsd/Cpb:WU rats (8 males and 8 females) were administered ( via gavage) a single dose of [pyrazole-3- 14 C] BYF 14182 (BECH 2136: Test 1 ma les; KATH 6012; Test 2 female s; chemical/radiochemical purity >98%; chemical purity 99.5%) in 0.5% aqueous Tragacanth solution at a dose of 5.3 mg/kg bw (males) or 5.4 mg/kg bw (females). The distribution of the total radioactivity to and elimination from the blood, organs and tissues we re analyzed qualitatively and quantitatively by whole-body autoradioluminography (WBAL). The ki netic behavior of BYF 14182, labeled with

14 C in the 3-position of the pyrazole ring of the molecule, was inve stigated over a period of seven days. One rat/sex was sacrificed at 1, 4, 8, 24, 48, 72, 120, or 168 hours after dose for cryosectioning. The amount of radioactivity in th e excreta (urine and faeces) and exhaled air

were determined also. BYF 14182 was readily absorbed from the gastro intestinal tract and quickly distributed throughout the body. For both sexes, th e excretion of radioactivity via urine and faeces was almost complete after 3 days. During the test period of 7 days, male rats showed higher faecal (up to ≈ 65%) than urinary (up to ≈ 34%) excretion, whereas urinary (up to ≈ 57%) and faecal (up

to ≈ 61%) excretion were similar in the female rats. Less than 0.1% of the administered radioactivity was exhaled as 14 CO 2 or other volatiles during a sampling period of 48 hours (both sexes).

In male rats, maximum total radioactiv e residue (TRR) values were reached for all organs and tissues at one hour after administration (t

max ). The values for liver, kidney, myocardium, adrenals, and Harderian gland were higher than in the blood. A similar distribution was observed throughout the study period of seven days.

In female rats, maximum TRR values were also reached for all organs and tissues at one hour after administration, and the values for liver, ki dney, brown fat, myocardium, pancreas, most glandular organs, ovary, and uterus were higher than in the blood. From peak values, a biphasic dec line of radioactivity concentrati ons was observed for all organs and tissues over the 7-day period. Seven days af ter administration, low but still quantifiable radioactive residues (<0.05 μg active substance- equiv./g) were measured in some organs. This metabolism study in the rat is classified acceptable/guideline and it satisfies the guideline requirement for a metabolism study [OPPTS 870.7485, OECD 417] in rats when considered in conjunction with the ADME metabolism studies in rats (MRID 48023831 using the [phenyl-UL13C6/14C] labeled BYF 14182 and MRID 48023832 us ing the [pyrazole-3-14C] labeled BYFPenflufen Hum an Health Risk Assessment D387450

Page 86 of 106 14182) and the quantitative whole body autora diography study in rats (MRID 48023833 using the [phenyl-UL-13C6/14C] labeled BYF 14182).

Executive Summary: In a metabolism study (MRID 48023835), 3 groups of Wistar Hsd/Cpb:WU rats (4 rats/sex/time point) were or ally administered by gavage with a single dose of [Phenyl-UL- 13 C 6 / 14 C] BYF 14182 [Batch # KATH 6038 (m ales: Tests 1-3) and KATH 6616 (females: Tests 4-6); >99% purity; radiochemical purity >98%-99%] in 0.5% aqueous Tragacanth solution at a dose level of 5 mg/kg bw. The rats were sacrifi ced 1, 4, or 24 hours after dosing. At each sampling interval, urine, blood, li ver and kidney samples, and gastrointestinal tract (GIT) and residual carcass were taken. The depletion of radioactiv e residues from organs and tissues (plasma, liver and kidney), the excretion with urine, and the metabolism of BYF 14182 were investigated. The overall recovery ranged from 90.4% to 102.3% of the administered dose in male rats and

from 96.8% to 99.8% in female rats. The renal excretion started immediately (1 hour) after administration and increased until 24

hours to 32.3% and to 49.2% of the administered dose in male and female rats, respectively. At the earlier time intervals, a similar % of the dose was noted between the sexes [8.2%/9.0% (M/F) at 1 hour and 20.7%/20.5% (M/F) at 4 hours]. The maximum total radioactive residue (TRR) levels were detected in organs and tissues, as well as in the combined GIT plus faeces at one hour after administration (t

max ). The distribution of the radioactivity within blood, liver and kidney was rapid. A signifi cant decline of radioactivity concentrations was observed for all organs and tissues over the 24-hour test period. BYF 14182 was metabolized extensively. Meta bolic reactions were detected at ≥ 10 different structural positions of the molecule. The ma jority of metabolites (58% to 94%) were

identified. Other unknown metabolites were characterized by their extraction and chromatographic behavior. The metabolism was qualitatively similar in male and female rats. Differences occurred only in terms of quantity with respect to individual meta bolites in urine, plasma, liver and kidney of

males and females. The major biotransformation reactions of [phenyl-UL- 13 C 6 / 14 C] BYF 14182 in male and female rats were demethylation (in the pyrazole ring) and hydroxylation reactions followed by further oxidation in different positions of the molecule. The C3-position of the alkyl side chain was a preferred hydroxylation site. Many metabolites originating from BYF 14182-3-hydroxy-butyl were identified. The principal metabolic reactions in the rat were: N-demethylation in the pyrazole ring hydroxylation at the following positions of the molecule: the alkyl side chain of the phenyl ring, the posit ion 4’ of the phenyl ring and the methyl group in position 3 of the pyrazole ring further oxidation of the hydroxyl group in position 2 of the alkyl side chain to form a keto

metabolite further oxidation of the hydroxyl group in the pos ition 4 of the alkyl side chain to form a carboxylic acid metabolite oxidative cleavages of the alkyl side chain fo rming an acetyl- or a carboxylic acid moiety conjugation of the hydroxyl group in the posi tion 4’ of the phenyl ring and in the position 2 of the alkyl side chain with glucuronic acidPenflufen Hum an Health Risk Assessment D387450

Page 87 of 106 further oxidation of the hydroxymethyl group of the pyrazole ring to form a carboxylic acid

metabolite

The metabolism results are in good agreement with those obtained from the ADME rat study conducted with the phenyl radiolabel led test substance (MRID 48023831; IIA 5.1 /01). A proposed metabolic pathway was identified.

This metabolism study is classified acceptabl e/guideline, and it satisfies the guideline requirement for a metabolism study [OPPTS 870.7485, OECD 417] in rats when considered in conjunction with the ADME metabolism studies in rats (MRID 48023831 using the [phenyl-UL13 C 6 / 14 C] BYF 14182 and MRID 48023832 using the [pyrazole-3- 14 C] labeled BYF 14182) and the quantitative whole body autoradiography studies in rats (MRID 48023833 using the [phenylUL- 13 C 6 / 14 C] BYF 14182 and MRID 48023834 using the [pyrazole-3- 14 C] labeled BYF 14182).

Executive Summary: In a rat metabolism study (MRID 48023836), four male Wistar Unilever Hsd/Cpb:WU rats were administered a si ngle oral dose (gavag e) of [Pyrazole-3- 14 C] BYF 14182-3-hydroxy-butyl [batch nos. BECH 2 173; >99%] in 0.5% aqueous Tragacanth solution at a dose of 2 mg/kg bw and sacrificed after 72 hours. The total radioactivity was determined in plasma, urine, faeces, and in organs and tissues at sacrifice. The metabolism was investigated by HPLC with radioactivity detection a nd spectroscopic methods in selected urine samples and faeces extracts.

The absorption of BYF 14182-3-hydroxy-butyl be gan immediately after administration. The maximum equivalent concentration in plasma (C

max ≈ 0.57μg/mL) was reached 40 minutes (0.67 hours) after dosing (t

max ). The radioactivity in the plasma declined to ≈ 0.4% of the maximum within 72 hours post administ ration. All of the administered-radioactivity (100.7%) was recovered in plasma, urine, faeces, organs, and tissues at sacrifice.

The renal excretion accounted for 25% of the ad ministered dose, with the majority of the radioactivity (75%) being excreted with the faeces of the male rats. Low amounts (0.34% of administered dose) of re sidue were found in organs and tissues at

sacrifice 72 hours after administ ration. Negligible amounts (0.05% of administered dose) of radioactivity were found in the gastrointestinal tract (GIT). The highest equivalent concentration was detected in the liver ( ≈ 0.044 μg/g), with lower concentrations in erythrocytes ( ≈ 0.039μg/g) and in kidneys ( ≈ 0.013 μg/g). The concentrations in the other organs and tissues were low and ranged from 0.001μg/g to 0.007μg/g. Based on these observations, the biokinetic behavior of BYF 14182-3-hydroxy-butyl and BYF 14182 was very similar. BYF 14182-3-hydroxy-butyl was extensively metabo lized in the rat. Metabolic reactions were observed in the same structural position s as detected for BYF 14182. The majority of metabolites ( ≈ 60% of the administered dose) were iden tified. Another 15% of metabolites were characterized by their extraction and chromatographic behavior. Only low amounts of the unchanged parent compound were dete cted in the urine and faeces extracts. The majority of the metabolites were demethylat ed in the pyrazole ring. Further hydroxylation of BYF 14182-3-hydroxy-butyl is another major meta bolic reaction yieldi ng di- and trihydroxy compounds. Further oxidation of one of the hydroxy groups to keto compounds or carboxylic

acids was also observed. Metabo lites, originating from cleavage in the alkyl side chain withPenflufen Hum an Health Risk Assessment D387450

Page 88 of 106 further oxidation, were detected. Low amounts of pyrazole label specific metabolites originating from the cleavage of the carboxamide bond or N-phe nyl bond, were detected in urine and faeces

extracts. All metabolites that were postulated to be formed from the intermediate BYF 14182-3- hydroxy-butyl in the metabolism study with BYF 14182 (IIA 5.1 /01 and IIA 5.1 /02) were

detected after administration of BYF 14182-3-hydroxy-butyl also.

The main metabolic reac tions of [pyrazole-3- 14 C] BYF 14182-3-hydroxy-butyl in rats detected

were: N-demethylation in the pyrazole ring further hydroxylation at the following positions of the molecule: the alkyl side chain of the phenyl ring, the position 4’ of th e phenyl ring and the methyl gr oup in position 3 of the pyrazole ring further oxidation of the hydroxy group in the positi on 2 of the alkyl side chain forming a keto

group further oxidation of the hydroxy group in the po sition 4 of the alkyl side chain forming a carboxylic acid oxidative cleavages of the alkyl side chain fo rming an acetyl group or a carboxylic acid group conjugation of the hydroxy group in the posi tion 4’ of the phenyl ring and in the position 2 of the alkyl side chain with glucuronic acid further oxidation of the hydroxymethyl group of the pyrazole ring forming a carboxylic acid

group conjugation of a trihydroxy compound with cysteine cleavage of the carboxamide bond forming carboxylic acid, which was further metabolized via conjugation with glucuronic acid cleavage of the N-phenyl bond forming the carboxamide

The very similar biokinetic and metabolic behavior of BYF 14182-3-hydroxy-butyl and BYF 14182 in 2 mg/kg-dosed male rats shows that the metabolism of BYF 14182 proceeds via BYF 14182-3-hydroxy-butyl as a key systemic intermediate

.

This metabolism study in male rats is classifi ed acceptable/guideline, and it satisfies the guideline requirement for a metabolism study [OPPTS 870.7485, OECD 417] in rats when considered in conjunction with the related metabolism studies in rats (MRID 48023832) using the [pyrazole-3- 14 C] labeled BYF 14182; (MRID 48023831).

870.7600 Dermal Absorption - Rat Executive Summary: In an in vivo dermal penetration study (MRID 48024009), [ 14 C]-BYF 14182 in a FS 240 red formulation (99.5%, Lot/batch No NLL7306-17) was applied to the dorsal surface of 16 male Wistar Rj: WI (IOPS HAN) rats/group at con centrations of 1, 50, or 240 g/L for 8 hours. The achieved doses ranged from 0.010 to 0.011 mg/cm 2 , 0.50 to 0.53 mg/cm 2 , and 2.63 to 2.73 mg/cm 2 , respectively. Following the 8-hour e xposure period, the remaining test material was washed off the skin, and a skin tape stripping procedure was performed. Four rats in each group were sacrificed at 8, 24, 72, or 168 hour s after dermal application. The amount of radioactivity absorbed, excreted, and pres ent on or in the skin was quantified.Penflufen Hum an Health Risk Assessment D387450

Page 89 of 106 Summary Table. Dermal Absorption Rate Dose level (g/L) Mean % of applied dose absorbed and in/on skin

Termination time C 8 hours 24 hours 72 hours 168 hours (n=4 rats/group) absorbed A skin B absorbed skin absorbed skin absorbed skin

240 0.277 0.942 0.306 1.136 0.520 0.255 0.960 0.274

50 1.584 2.030 0.699 2.199 1.830 3.322 2.388 0.355

1 1.624 2.738 3.035 0.970 4.948 0.401 3.770 0.297

A % of applied dose directly absorbed

B % of applied dose at dose site

C Following a single 8-hour exposure period

The overall recovery of radiolabel was acceptabl e, with the mean recoveries ranging from 90.4% to 93.3% (240 g/L dose), 96.9% to 102.6% (50 g/L dose), and 93.7% to 96.1% (1 g/L dose) of the applied dose. At all dose le vels, the majority of the radiol abel was not absorbed and was recovered from the skin by swabbing. The tota l amount non-absorbed ranged from 89%-92%, 92%-99%, and 89%-92% of the app lied dose at 240 g/L, 50 g/l, and 1 g/L, respectively. The total % of the applied dose at the dose site ranged from 0.26% to 1.14% (240 g/L dose), 0.36% to 3.32% (50 g/L dose), and 0.30 to 2.74% (1 g/L dose). The total % of the applied dose directly absorbed ranged from 0.28% to 0.96% (240 g/ L dose), 0.70% to 2.39% ( 50 g/L dose), and 1.62% to 4.95% (1 g/L dose) over the 168-hour obs ervation period. Following an 8-hour exposure period, the amount of [ 14 C]-BYF 14182 potentially absorbable (sum of direct absorption and amount detected in the skin) ranged from 0.78% to 1.44% for the neat product, from 2.74% to 5.15% for the 50 g/L dose, and from 4.00% to 5.35% for the 1 g/L dose.

This study is classified as tota lly reliable (acceptable/guideline), and it satisfies the guideline requirements (OCSPP 870.7600; OECD 427) for a dermal penetration study in rats.

Executive Summary: In an in vitro dermal penetration study (MRID 48024011), unlabeled BYF 14182 (purity 99.5%; Lot/Batch No. NLL7306-17) spiked with radiolabeled [phenyl- 13 C 6 / 14 C]- BYF 14182 (purity>98%; Batch No. KATH 6292) was applied at a rate of 10 μL/cm 2 to excised Wistar Rj: WI (IOPS HAN) ma le rat and female human dermatomed skin mounted in flowthrough diffusion cells. The single application was applied at th ree concentrations corresponding to the neat product (SYP13405, nominal value of 50 g BYF 14182/L formulation) and two dilutions (SYP13405, nominal value of 10 g BY F 14182/L formulation and SYP13407, nominal value of 1 g BYF 14182/L formulation). The am ount of compound applied ranged from 0.416 to 0.518 mg/cm 2 , 0.101 to 0.112 mg/cm 2 , and 0.0098 to 0.0105 mg/cm 2 , respectively. Receptor fluid samples were collected at hourly interval s for the duration of the study (24 hours). Eight hours post-application, the remaining test materi al on the skin membranes was washed off the skin using sponge swabs. At 24 hours post applica tion, the skin samples were swabbed again and tape-stripped to remove residua l dose and the stratum corneum. The skin samples were removed from the diffusion cells and analysed. The overall recovery of radioactivity was accep table for all experiments using rat (>93%) and human (>95%) dermatomed skin membranes. The amount of radioa ctivity in the receptor fluid (0-24 hours), receptor fluid at termination, a nd receptor chamber (cons idered as directly absorbed) was always greater for rat skin (0.352%, 1.309%, and 3.394% of the applied dose for the 50 g/L, 10 g/L, and 1 g/L dose formulati ons, respectively) than human skin (0.067%, 0.323%, and 0.780% of the applied dose for the 50 g/L, 10 g/L, and 1 g/L dose formulations,Penflufen Hum an Health Risk Assessment D387450

Page 90 of 106 respectively) under identical expe rimental conditions. The amount of radioactivity in the skin and stratum corneum (total % of applie d dose at dose site) was 3.763%, 4.445%, and 3.122% (rat) and 0.105%, 1.126%, and 0.678% (human), respectively. The mean total amounts of radioactivity considered to be potentially absorbable ( directly absorbed + total remaining at

dose site ) at doses of 50 g/L, 10 g/L, and 1 g/L were 4.115%, 5.754%, and 6.516%, respectively, for rat skin and 0.172%, 1.449%, and 1.457%, respectiv ely, for human skin. The mean % of the applied dose potentially absorbable was 24-fold, 4- fold, and 4.5-fold greater in the rat skin than in the human skin for the 50 g/L, 10 g/L, and 1 g/L dose formulations, respectively.

This study is classified as totally reliable (acceptable/guideline). There is no OCSPP guideline, but the study was performed according to the OECD 428 guideline for an in vitro dermal penetration study in the rat.

A.4.9 Immunotoxicity

870.7800 Immunotoxicity

Executive Summary : In an immunotoxicity study (MRID 48023837), BYF 14182 (Lot/Batch 2005-004498; 95.6%) was administered via the diet to 8 male and 8 female Wistar (Hsd Cpb:WU) rats per group, at concentrations of 0, 200, 1000 or 7000 ppm (equivalent to 17.9, 82.6 or 755.6 mg/kg bw/day in males and 20.4, 104.5 or 960.5 mg/kg bw/day in females) for a period of 29 (males) or 30 (females) days to invest igate potential immunotoxi c effects of BYF 14182. A Plaque Forming Cell (PFC) assay was performed us ing the spleen. The thymus and spleen were weighed, and cell counts in th e spleen were determined. No treatment-related mortalities or clinical sign s of toxicity were obs erved during the study in either sex. A slight reduction in body weight was observed in both sexes at 7000 ppm at termination ( ↓ 7% in males and ↓ 9% in females).

There were no treatment-related effects on spleen or thymus weights or total spleen cell counts. The plaque-forming assay showed no evidence oftreatment-related effects. A high interindividual variability was noted in all the treatment groups as well as in the contro l group. It is acknowledged that high inter-ind ividual variability is a norma l distribution of the immune response of out-bred strains. Ev aluation of individual animal da ta did not show any trend or

distribution that would dem onstrate significant suppression of anti-SRBC PFC response.

This study did not perform a Natural Killer (NK) cells activity assay. Evaluation of the available toxicity database on penflufen re vealed that decreased thymus we ights in males were observed at 7000 and 14000 ppm in a rat 90-day oral toxicity study. Decreased thymus and spleen weights were observed at 4000 ppm of pa rental and offspring of both sexes in a rat reproduction study. However, the decrease in thymus weight was co nsidered a secondary effect due to decreased body weight; the relative thymus weight was not significantly different from the control. In addition, the toxicology database of penflufen indicates that the ta rget organs are the liver and thyroid. The overall weight of evidence suggests that this chemical does not directly target the immune system. Therefore, NK cell activity assay is not required at this time.Penflufen Hum an Health Risk Assessment D387450

Page 91 of 106 The immunotoxicity NOAEL is 7000 ppm ( 755.6 mg/kg bw/day for males and 960.5 mg/kg bw/day for females); the LOAEL was not established.

This immunotoxicity study is classified as acceptable/guideline, and it satisfies the guideline requirement for an immunotoxicity study (OPPTS 870.7800).Penflufen Hum an Health Risk Assessment D387450

Page 92 of 106 Appendix B. Metabolism Data

B1. Structures and Identify of Metabolites of Penflufen

Table B1. Chemical structu re, codes and chemical names of penflufen metabolites.

Common Names /

Code IUPAC Name Chemical Structure

Penflufen

BYF 14182 N-[2-(1,3-Dimethylbutyl)phenyl] 5-fluoro-1,3- dimethyl-1H-pyrazole-4-carboxamide

BYF 14182-3- hydroxy-butyl

Pen-3HB

BCS-AA10006 5-fluoro-N-[2-(3-hydroxy-1,3-dimethylbutyl)phenyl]-1,3-dimethyl-1Hpyrazole-4-carboxamide

BYF 14182-3-hydroxy-butylglucoside

BCS-AA10006- glucoside 5-fluoro-N-{2-[3-(beta-D-glucopyranosyloxy)-1,3-dimethylbutyl]phenyl}-1,3-dimethyl1H-pyrazole-4-carboxamide

BYF 14182-3-hydroxy-butylmalonyl-glucoside

BCS-AA10006- malonyl-glucoside 3-(2-{[(5-fluoro-1,3-dimethyl-1H-pyrazol4-yl)carbonyl]amino}phenyl)-1,1- dimethylbutyl 6-O- (carboxyacetyl)-beta -D-glucopyranoside

BYF 14182-4-hydroxy-butylmalonyl-glucoside 4-(2-{[(5-fluoro-1,3-dimethyl-1H-pyrazol4-yl)carbonyl]amino}phenyl)-2- methylpentyl 6-O- (carboxyacetyl)-beta -D-glucopyranoside N N CH 3

C O

N H

H 3 C F CH

H 3 C CH 2

H CH

H 3 C C 3

N N CH 3

C O

N H

H 3 C F CH

H 3 C CH 2

C

H 3 C C 3 H

OH

N N CH 3

C O

N H

H 3 C F CH

H 3 C CH 2

C

H 3 C CH 3 O

O

OH

HO

HO OH

N N CH 3

C O

N H

H 3 C F CH

H 3 C CH 2

C

H 3 C CH 3 O

O

OH

O HO

O

HO OH O

N N CH 3

C O

N H

H 3 C F CH

H 3 C CH 2

CH

H 3 C C 2

O O

OH HO O O O

HO H

OHPenflufen Hum an Health Risk Assessment D387450

Page 93 of 106 Table B1. Chemical structu re, codes and chemical names of penflufe n metabolites.

Common Names / IUPAC Name Code Chemical Structure

BYF 14182- pyrazolyl-AAP

AE 2300037 N -(2-acetylphenyl)-5-fl uoro-1,3-dimethyl-1 H

pyrazole-4-carboxamide N H N

N O

O F CH

3

CH 3 CH

3

BYF 14182- homoglutathione

Pen-HGT

BCS-AA10790 Gamma-glutamyl-S-(4-{[2-(1,3-dimethylbutyl)phenyl]carbamoyl}-1,3-dimethyl1H-pyrazol-5-yl)cyste inyl-beta-alanine

BYF 14182- glutathione gamma-glutamyl-S-(4-{[2-(1,3-dimethylbutyl)phenyl]carbamoyl}-1,3-dimethyl1H-pyrazol-5-yl)cysteinyl-glycine

BYF 14182- cysteine S-(4-{[2-(1,3-dimethylbutyl)phenyl]carbamoyl}- 1,3-dimethyl-1H-pyrazol-5-yl)cysteine

BYF 14182- succinyl-cysteine 4-({1-carboxy-2-[(4-{[2-(1,3-dimethylbutyl)phenyl]carbamoyl}-1,3-dimethyl1H-pyrazol-5-yl)thio]ethyl}amino)-4-

oxobutanoic acid

BYF 14182-succinyl-cysteinylglycine N-(3-carboxypropanoyl)-S- (1,3-dimethyl-4-{[2-(4-methylpentan-2-yl)phenyl]carbamoyl}-1Hpyrazol-5-yl)cysteinylglycine N N CH 3

C O

N H

CH

H

H 3 H 3 C S H 3 C C 2

CH

H 3 C C H N

O N H O NH 2

O HO

O

OH

N N CH 3

C O

N

H

CH

H 3 C CH 2

CH

H 3 C CH 3

OH

O H 3 C S

H N

O N H O NH 2

O HO

N

N CH 3

C O

N H

CH

H 3 C S H 3 C CH 2

CH

H 3 C CH 3 H 2 N

O OH

N N CH 3

C O

N H

CH

H 3 C S H 3 C CH 2

CH

H 3 C CH 3 H N

O OH O O

HO

N N CH 3

C O

N H

H 3 C S CH

H 3 C CH 2

CH H N O

H 3 C CH 3

O N H O HO

O OHPenflufen Hum an Health Risk Assessment D387450

Page 94 of 106 Table B1. Chemical structu re, codes and chemical names of penflufe n metabolites.

Common Names / IUPAC Name Code Chemical Structure

BYF 14182- cysteinyl

succinimide 3-[(1,3-dimethyl-4-{[2-(4-methylpentan-2-yl)phenyl]carbamoyl}-1Hpyrazol-5-yl)sulfanyl]-2-(2,5- dioxopyrrolidin-1-yl)propanoic acid

BYF 14182-

sulfonic acid 1,3-dimethyl-4-{[2-(4-methylpentan-2-yl)phenyl]carbamoyl}-1H-pyrazole5-sulfonic acid

BYF 14182- hydroxy-sulfonic

acid Structure not specified

BYF 14182-hydroxy-acetylcysteine Structure not specified

BYF 14182- pyrazole-4-

carboxamide

Pen-PCX

BCS-AA10791 5-Fluoro-1,3-dimethyl-1H-pyrazole-4-

carboxamide

BYF 14182-bis – desmethyl-3- carboxylic acid

Pen-D3C

BCS-CM41431 5-Fluoro-1H-pyrazole-3-carboxylic acid N N CH 3

C O

N H

H 3 C S CH

H 3 C CH 2 OH

CH

H 3 C CH 3

N O O O

N

N N H

H 3 C S O 3 H CH

H 3 C CH 2

CH

H 3 C CH 3 CH 3

C O

N H

H 3 C S O 3 H CH

H 3 C CH 2

CH

H 3 C CH 3 +O N CH 3

C O

N

N N CH 3

C O

N H

CH

H 3 C CH 2

CH

H 3 C CH 3

H +O H 3 C S

H N

O O O H 3 C

N

N NH

H 3 C F CH 3

C O

2

N

HN C O

OH

FPenflufen Hum an Health Risk Assessment D387450

Page 95 of 106 Table B1. Chemical structu re, codes and chemical names of penflufe n metabolites.

Common Names / IUPAC Name Code Chemical Structure

BYF 14182-hydroxy-mercaptolactic acid Structure not specified

BYF 14182-desmethyldicarboxylic acid 5-fluoro-1H-pyrazole-3,4-dicarboxylic acid

BYF 14182-desmethylpyrazole-4-

carboxamide 5-fluoro-3-methyl-1H-pyrazole4-carboxamide

BYF 14182-bisdesmethyl-3- carbonyl-serine Structure not completely specified

BYF 14182 –

fluoro acid 5-fluoro-1,3-dimethyl-1H-pyrazole-4- carboxylic

acid

BYF 14182- desmethyl-2,3- dihydroxy N-[2-(2,3-dihydroxy-1,3- dimethylbutyl)phenyl]- 5-fluoro-3-methyl-1H-pyrazole-4-carboxamide

BYF 14182- desmethyl-3- hydroxy-ketone 5-fluoro-N-[2-(3-hydroxy-1,3-dimethyl-2- oxobutyl)phenyl]-3-methyl-1H-pyrazole-4-

carboxamide N N CH 3

C O

N H

CH

C CH 2

CH

3 C CH 3 +O H 3 C S H 3

H

HO

O OH

HN N C

OH

F C O OH O

HN N C

F CH 3 O

NH 2

HN N

F C O serine

N N C

OH

H 3 C F CH 3 O

N

H F CH

H 3 C

C

H 3 C C OH

OH N CH 3

C O

N H

H 3

N CH 3

C O

N H

N

H F CH

H 3 C

C

H 3 C CH 3 O

OHPenflufen Hum an Health Risk Assessment D387450

Page 96 of 106 Table B1. Chemical structu re, codes and chemical names of penflufe n metabolites.

Common Names / IUPAC Name Code Chemical Structure

BYF 14182-desmethylhydroxymethyl-2,3- dihydroxy N-[2-(2,3-dihydroxy-1,3- dimethylbutyl)phenyl]- 5-fluoro-3-(hydroxymethyl)-1H-pyrazole-4-

carboxamide

BYF 14182-desmethyl-acetylcarboxylic acid 4-[(2-acetylphenyl)carba moyl]-5-fluoro-1Hpyrazole-3-carboxylic acid

BYF 14182-hydroxy-ketocarboxylic acid Structure not completely specified

BYF 14182- dihydroxy (isomer 1 and 2) Structure not completely specified

BYF 14182-1,3,4’- trihydroxy N-[2-(1,3-dihydroxy-1,3-dimethylbutyl)-4-hydroxyphenyl]-5-fluoro-1,3-dimethyl)-1Hpyrazole-4-carboxamide

BYF 14182-3,4’- dihydroxy 5-fluoro-N-[4-hydroxy-2-(3-hydroxy-1,3-dimethylbutyl)phenyl]-1,3-dimethyl-1Hpyrazole-4-carboxamide N

H F CH

H 3 C

H 3 N CH 2

C O

N H

C

C CH 3 OH

OH HO

N N C O

N H

H F C

H 3 C O C HO O

+2O -2H

N C

C O

N H HO O

N

H 3 C F CH

H 3 C CH 2

H 3 C CH 3

+2O

N CH 3

C O

N H

H

H 3 N

H 3 C F CH

H 3 C C 2

H 3 C C

N H

H 3 C F C

H 3 C CH 2

H 3 C C OH

OH N CH 3

C O

N

H 3 OH

N CH 3

C O

N H OH

N

H F CH

H 3 C

C

H 3 C CH 3

OHPenflufen Hum an Health Risk Assessment D387450

Page 97 of 106 Table B1. Chemical structu re, codes and chemical names of penflufe n metabolites.

Common Names / IUPAC Name Code Chemical Structure

BYF 14182-3,4’-dihydroxyglucuronide 4-{[(5-fluoro-1,3-dimethyl-1H-pyrazol-4- yl)carbonyl]amino}-3-(4-hydroxy-4-methylpentan-2-yl)phenyl beta-Dglucopyranosiduronic acid

BYF 14182 - 2,3,4’-trihydroxy N-[2-(2,3-dihydroxy-1,3-dimethylbutyl)-4-hydroxyphenyl]-5-fluoro-1,3-dimethyl-1Hpyrazole-4-carboxamide

BYF 14182-3,4’- dihydroxy-ketone 5-fluoro-N-[4-hydroxy-2-(3-hydroxy-1,3-dimethyl-2-oxobutyl)phenyl]-1,3-dimethyl-1Hpyrazole-4-carboxamide

BYF 14182-3,4’-dihydroxy-ketoglucuronide 4-{[(5-fluoro-1,3-dimethyl-1H-pyrazol-4-yl)carbonyl]amino}-3-(3-hydroxy-1,3-dimethyl2-oxobutyl)phenyl beta-D-glucopyranosiduronic

acid

BYF 14182- 3- hydroxy-pentanoic

acid 4-(2-{[(5-fluoro-1,3-dimethyl-1H-pyrazol-4- yl)carbonyl]amino}phenyl-2-hydroxy-2- methylpentanoic acid

BYF 14182-4’- hydroxy – glucuronide (isomer 1 and 2) 3-(1,3-dimethylbutyl)-4-{[(5-fluoro-1,3,dimethyl1H-pyrazol-4-yl)carbonyl]amino}phenylbeta-Dglucopyranosiduronic acid N

H F CH

H 3 C

C

H 3 C C 3

OH N CH 3

C O

N H

H O

O OH

O OH OH OH

N H

H 3 C F CH

H 3 C CH

H 3 C C 3

OH OH N CH 3

C O

N

H OH

N H

H F CH

H 3 C

C

H 3 C CH 3

OH O N CH 3

C O

N OH

N

H F CH

H 3 C

C

H 3 C CH 3 O

OH O N CH 3

C O

N H O

O OH

OH OH OH

N

H 3 C F CH

H 3 C CH 2

H 3 C C

OH

O OH N CH 3

C O

N H

N

H F CH

H 3 C

CH

H 3 C CH 3 O OH N CH 3

C O

N H O

O OH

OH OHPenflufen Hum an Health Risk Assessment D387450

Page 98 of 106 Table B1. Chemical structu re, codes and chemical names of penflufe n metabolites.

Common Names / IUPAC Name Code Chemical Structure

BYF 14182- desmethyl-4-carboxylic acidglucuronide Structure not completely specified

BYF 14182- pentanoic acid,

isomer 1 and 2 4-(2-{[(5-fluoro-1,3-dimethyl-1H-pyrazol-4- yl)carbonyl]amino}phen yl)-2-methylpentanoic

acid

BYF 14182-desmethylpentanoic acid 4-(2-{[(5-fluoro-3-methyl-1H-pyrazol-4- yl)carbonyl]amino}phen yl)-2-methylpentanoic

acid

BYF 14182-3,4,4’- trihydroxy N-[2-(3,4-dihydroxy-1,3-dimethylbutyl)-4-hydroxyphenyl]-5-fluoro-1,3-dimethyl-1Hpyrazole-4-carboxamide

BYF 14182-desmethyldihydroxy-ketone 5-fluoro-N-{2-[3-hydroxy-1-(hydroxymethyl)-3-methyl-2-oxobutyl]phenyl}-3-methyl-1Hpyrazole-4-carboxamide

BYF 14182-desmethylhydroxymethylpentanoic acid* 4-[2-({[5-fluoro-3-(hydroxymethyl)-1H-pyrazol4-yl]carbonyl}amino)phenyl]-2-methylpentanoic

acid

BYF 14182- desmethyl-3-hydroxy-ketocarboxylic acid* 5-fluoro-4-{[2-(3-hydroxy-1,3-dimethyl-2- oxobutylyl]phenyl]carbamoyl}-1H-pyrazole]-3- carboxylic acid N N C

OH

H F glucuronic

acid CH 3 O +

N H

H 3 C F CH

H 3 C CH 2

H 3 C C

O N CH 3

C O

N

OH

N N N H

H F CH

H 3 C CH 2

H 3 C C

O OH CH 3

C O

N

H 3 C F CH

H 3 C CH 2

H 3 C C 2

OH OH N CH 3

C O

N H

H OH

N H

H F CH

C H 2 C

H 3 C CH 3

OH O HO N CH 3

C O

N

N

H F CH

H 3 C CH 2

H 3 C C OH

O N CH 2

C O

N H HO

N

H F CH

H 3 C C

H 3 C CH 3 O

OH N C

C O

N H HO OPenflufen Hum an Health Risk Assessment D387450

Page 99 of 106 Table B1. Chemical structu re, codes and chemical names of penflufe n metabolites.

Common Names / IUPAC Name Code Chemical Structure

BYF 14182-2,3,4- trihydroxy 1,2-dideoxy-2-(2-{[(5-fluoro-1,3-dimethyl-1Hpyrazol-4-yl)carbonyl]amino}phenyl)-4-Cmethylpentitol

BYF 14182- desmethyl-4- carboxylic acid 5-fluoro-3-methyl-1H-pyrazole-4-carboxylic acid N

H 3 C F H 3

N CH 3

C O

N H

CH

C CH

H 3 C CH 2

OH OH OH

N N C

OH

H F O CH 3

*Identification was not unambiguous.

B2. Plant Metabolism Study Summaries

Potato metabolism studies The metabolism of penflufen was investigated in potatoes treated with pe nflufen labeled in the phenyl and pyrazole rings. Additionally, studies for each label were conducted reflecting both seed treatment (~0.005 lb ai/100 lbs seed) and in -furrow (~0.5 lbs ai/A) a pplications at rates approximately twice the currently proposed use pattern. Mature t ubers were harvested from all four applications and potato leaves were harveste d from the pyrazole label in-furrow application. No significant differences were noted either based on label positi on or on application technique. Total radioactive residue (TRR) was low in all tuber samples with the in-furrow tubers having higher residues likely due to a hi gher application rate. The major residue in tubers was the parent compound at ~20 - 30% of the TRR; minor amounts of penflufen-3-hydroxybutyl (Pen3HB) were found from the in-furrow application of phenyl labeled penflufen at 12% of the TRR.

Other metabolites identified were all < 10% of th e TRR. In pyrazole treated potato leaves from the in-furrow application, the TRR was significantly higher in the leaves than in the tubers from the same study, though the TRR in the leaves was st ill at low levels. The major residue in the leaves was Pen-3HB at 19% of the TRR and pe nflufen-3-hydroxybutyl glucoside at 11% of the

TRR. All other identified metabol ites were <10% of the TRR. Extractability of the residues in these studies was high and the identification acceptable. Two routes of degradation are postulated for penflufen in potatoes: 1) subst itution of glutathione for fluorine in the pyrazole ring followed by hydrolysis of the glutathione mo iety to cysteine; and 2) hydroxylation of the third carbon on the butyl substituent, followed by conjugation with gluc ose and malonic acid.

Wheat metabolism studies The metabolism of penflufen was investigated in spring wheat treated with penflufen labeled in the phenyl and pyrazole rings. Studies for each la bel were conducted reflecting seed treatment at 0.05 lbs ai/100 lbs seed (1x the currently proposed rate) and 0.5 lbs ai/100 lbs seed (10x thePenflufen Hum an Health Risk Assessment D387450

Page 100 of 106 currently proposed rate). Forage, hay, grain a nd straw samples were co llected and analyzed. The TRR in grain from both application rates and labels was very low precluding attempts at identification. Higher TRR values were observed in forage, hay and straw with residues being highest in straw, followed by hay and forage. The major residue in forage, hay and straw was penflufen-3-hydroxybutyl-malonyl-glucoside at ~20-35% of the TRR and 4-hydroxybutylmalonyl-glucoside at ~10–20% of the TRR. Th e parent compound and other minor metabolites

were identified and all were < 10% of the TRR. Of note, in the pyrazole ring labeled study, very minor amounts of the cleavage product, penf ulufen-pyrazole-4-carboxamide (Pen-PCX) were noted in hay and straw. In the phenyl ring labeled study no metabolites specific to the phenyl ring were detected. Extractability of the residues in these studie s was high and the identification acceptable. Three routes of degradation are postula ted for penflufen in wheat: 1) substitution of glutathione for fluorine on the pyrazole ring follo wed by hydrolysis of the glutathione moiety to cysteine; 2) hydroxylation of the third or fourth carbon on the butyl substituent, followed by conjugation with glucose and mal onic acid; and 3) cleavage of the N-phenyl linkage to yield

Pen-PCX.

Soybean metabolism studies The metabolism of penflufen was investigated in soybeans treated with penflufen labeled in the phenyl and pyrazole rings. Studies for each labe l were conducted reflecting both seed treatment at 0.05 lbs ai/100 lbs seed (1x the currently pr oposed rate) and 0.5 lbs ai/100 lbs seed (10x the currently proposed rate). Soybean forage, hay a nd seed were collected and analyzed. The TRR in soybean seed was low with the highest TRR in forage followed by hay. The major residue inseed included penflufen-homoglutathione (Pen-HGT) at 22–77% of the TRR and penflufendesmethyl-dicarboxylic acid (pyrazole ring only) at 65% of the TRR. In forage the major

residues were Pen-HGT at 56-60% of the TRR a nd cysteine at 10–13% of the TRR. In hay the major metabolites included Pen-HGT at 21–46% of the TRR, penflufen-3-hydroxybutylmalonyl-glucoside at 37–38% of the TRR and pa rent compound (phenyl ring label study only) at

14% of the TRR. Other minor metabolites were identified and all were <10% of the TRR. Extractability of the residues in these studies was high and the identification acceptable. Three routes of degradation are postu lated for penflufen in wheat: 1) hydrolysis of the fluorine substituent on the pyrazole ring, followed by glut athione conjugations and subsequent hydrolysis of the glutathione moiety; 2) hydroxylation of th e third carbon on the butyl substituent, followed by conjugation with glucose and malonic acid; and 3) cleavage of the N-phenyl linkage followed by hydrolysis of the resulting amide to carboxylic acid, oxidation of the C3-methyl substituent, and loss of the N-methyl substituent to yiel d penflufen-desmethyl-dicarboxylic acid.

Rice metabolism studies The metabolism of penflufen was investigated in dry-seeded rice treated with penflufen labeled in the phenyl and pyrazole rings. Studies for each label were conducted reflecting soil treatment at transplant at 0.45 lbs ai/A. Rice kernels, hus ks and straw were collected and analyzed. The TRR in kernels was low with high levels of TR R found in straw and moderate residues found in husks. The major residue in seed included th e parent compound at 20-31% of the TRR and Pen3HB at 20-23% of the TRR. In rice husks the major residue was parent at 15-27% of the TRR

and Pen-3HB at 23-24% of the TRR. Other minor metabolites were identified in kernels and

husks and all were <10% of the TRR. In ri ce straw multiple metabolites were identified, with no metabolite present at levels greater than 6% of the TRR. Extractability of the residues inPenflufen Hum an Health Risk Assessment D387450

Page 101 of 106 these studies was high and the identification accep table. Three routes of degradation are postulated for penflufen in wheat: 1) hydrolysis of the fluorine substitu ent on the pyrazole ring, followed by glutathione conjugations and subsequent hydrolysis of the glutathione moiety; 2) hydroxylation of the third carbon on the butyl subs tituent, followed by conjugation with glucose and malonic acid; and 3) cleavage of the N- phenyl linkage followed by hydrolysis of the resulting amide to carboxylic acid, oxidation ofthe C3-methyl substituent, and loss of the Nmethyl substituent to yield penflufen-desmethyl-dicarboxylic acid.

B3. Livestock Metabolism Studies

Poultry metabolism studies The metabolism of penflufen in poultry was investig ated using laying hens orally dosed at a rate equivalent to 25 - 27 ppm in the feed of pyrazole or phenyl ring labeled pe nflufen. Twelve hens, six dosed with pyrazole ring labeled penflufen a nd six dosed with phenyl ring labeled penflufen

were dosed 14 times at 24 hour intervals and sacrif iced about six hours after the last dose. Total radioactivity was measured in the excreta and eg gs daily, as well as in the poultry muscle, fat, liver and skin at sacrifice. The majority of the administered dose was recovered in the excreta. Residues in eggs increased linearly reaching a plateau between day 6 and 8. The highest tissue

TRR values were measured in the liver and kidney, with lower levels in the skin, fat and muscle. The major residue in eggs was the parent co mpound at 12% with multiple minor metabolites detected, all at <10% of the TRR. The majo r residue in fat was parent, which was the only compound identified at 74- 8% of the TRR. In muscle, the only metabo lite identified at over 10% of the TRR was 3,4’-dihydroxy-keto-gluc uronide at 10% of the TRR, no parent was

detected in muscle. Low levels of various minor metabolites were identified in muscle, all below 10% of the TRR. In liver, no metabolite greate r than 10% was identified and parent was not

detected even as a minor metabolite.

No significant difference in metabolic profile was seen between the pyrazole and phenyl ring labeled studies. Parent was the major metabolit e in fat and seen at 10% of the TRR in eggs, however penflufen is extensively metabolized in the laying hen with over 50 metabolites

identified or characterized in the different tissu es. The main metabolic pathways in the hen are N-demethylation in the pyrazole ring, hydroxylation at the various positions of the molecule, further oxidation of hydroxyl groups forming keto and carboxylic acid groups, oxidative cleavage of the alkyl side chain forming an acetyl compound and conjugations of the hydroxyl group in the 4’-position of the phe nyl ring with glucuronic acid.

Ruminant metabolism studies The metabolism of penflufen in ruminants was inve stigated using lactating goats orally dosed at a rate equivalent to 48 ppm in the feed. Two goats, one dosed with pyrazole ring labeled penflufen and one dosed with phenyl ring labe led penflufen were dosed 5 times at 24 hour

intervals and sacrificed about twenty four hours after the la st dose. Total radioactivity was

measured in the milk and excreta at timed interval s as well as in liver, kidney, muscle and fat at sacrifice. The majority of the administered dose was recovered in the excreta. The highest tissue TRR values were measured in liver, followed by kidney, fat and muscle. In milk, the major residues were 2,3,4’-trihydroxy (isomer 1) at 17- 24% of the TRR, 3,4’-dihydroxy at 14-16 % of the TRR, and 2,3,4’-trihydroxy (isomer 2) at 10% of the TRR. Additional minor metabolitesPenflufen Hum an Health Risk Assessment D387450

Page 102 of 106 were identified at <10% of the TRR. In muscle , multiple minor metabolites were identified with 3,4’-dihydroxy as the only metabolite >10% ofthe TRR at 15-18%. In fat, 3,4’-dihydroxyglucuronide and 3,4’-dihydroxy were identified at 15 and 14% of the TRR, respectively. Multiple minor metabolites were identified in fat, all <10% of the TRR. In liver multiple metabolites were identified with 3,4’-dihydroxy-glu curonide being the only metabolite >10% of the TRR at 10 - 15%. Likewise in kidney, multiple metabolites were identified with pentanoic acid (isomer 2) and 3,4’-dihydroxy-glucuronide bei ng the only metabolites >10% of the TRR at 16–17% and 10 - 13%, respectively.

No substantive difference in metabolic profile was seen between the pyrazole and phenyl ring labeled studies. Penflufen is extensively meta bolized in the ruminant as demonstrated by the high level of identified metabolites present at low levels (<10% of the TRR). The main metabolic pathways in the ruminant are N-deme thylation in the pyrazole ring, hydroxylation at the various positions of the molecule, further ox idation of the hydroxyl group in the 2-position of the alkyl side chain forming a keto group, oxidation of a terminal methyl group of the alkyl side chain to a carboxylic acid group, an d conjugation of the hydroxyl group in the 4’-position of the phenyl ring with glucuronic acid.Penflufen Hum an Health Risk Assessment D387450

Page 103 of 106 Appendix C. Physical/Chemical Properties

Table C1. Physical/Chemical Properties of Penflufen

Parameter Value Reference

Molecular Weight 317.41 g/mol MRID No. 48023535

pH 6.7 (1% suspension in distilled water @ 22°C) MRID No. 48023525

Water solubility (20°C) @ pH 4 = 11.0 mg/L @ pH 7 = 10.9 mg/L @ pH 9 = 11.2 mg/L MRID No. 48023535

Solvent solubility (20°C ) Solvent g/L

methanol 126 n-heptane 1.6

toluene 62

dichloromethane >250

acetone 139 ethylacetate 96 dimethyl sulfoxide 162 MRID No. 48023536

Vapor pressure (25°C) 9.0 x 10 -9 torr MRID No. 48023537

Dissociation constant, pKa No dissociation constant (pKa) was found in aqueous solution of penflufen in the range of 1<pH<12. The

molecule has no structural moieties which are prone to dissociate. MRID No. 48023532

Henry’s law constant 1.04 x 10 -10 atm·m 3 /mol MRID No. 48023539

Octanol/water partition coefficient, log K OW (25°C) @pH 7 = 3.3 MRID No. 48023534

Hydrolysis t 1/2 at 50°C Stable MRID No. 48023547

Aqueous photolysis t 1/2 at 25°C 83.2 days MRID No. 48023548

Aerobic soil metabolism t 1/2 at 25°C (combined radio-label half-life) 249 days (silt loam) 433 days (sandy loam)* MRID No. 48023553

Aerobic soil metabolism t 1/2 at 20oC 117 days (silt loam) 165 days (sandy loam)* 243 days (loam)* 129 (loam)* MRID No. 48023552,

AAP (degradate) 257 days (sandy loam)* 116 days (silt loam) 231 days (loam)* 128 days (clay loam)* MRID No. 48023554

Anaerobic Soil Metabolism t 1⁄2 at 20°C 866 days* MRID No. 48023555

Aerobic aquatic metabolism t 1/2 at 20°C (sandy loam:sediment system, 2 radio-labels) 301 days* 267 days MRID No. 48023556

Anaerobic aquatic metabolism t 1/2 at 20°C (combined labels) Stable MRID No. 48023557

* Extrapolated beyond the study duration.Penflufen Hum an Health Risk Assessment D387450

Page 104 of 106 Appendix D. End Use Products and Detailed Label Restrictions

Table D.1. Penflufen End Use Products EPA Reg

No. Product Composition Labeled crops Proposed Restrictions Co-Formulants

264-RRRO PEN 240FS 22.7% penflufen

2 lbs penflufen/gal Alfalfa, dried and succulent legume vegetables including soybeans, cereal grains, cotton, sunflower, safflower, and potato (seed piece

treatment and infurrow) Do not use for feed, food or oil purposes. Store away from feeds and

foodstuffs.

Registered seed treatment crops and potatoes may be replanted at any

time. All other cr ops may be planted after 30 days. None

264-RREE PENPROME

177FS 3.59% penflufen

0.32 lb penflufen/gal Alfalfa, dried legume vegetables including soybeans, barley, wheat, triticale, and

rice. Do not use for feed, food or oil purposes. Store away from feeds and

foodstuffs.

Crops on this label or for which tolerances exist for penflufen may be replanted at any time. All other crops may be planted after 30 days. Prothioconazole and Metalaxyl

264-RREG PENPRO 118FS 9.35% penflufen

0.83 lb penflufen/gal Wheat, potato seed piece treatment Do not use for feed, food or oil purposes. Store away from feeds and

foodstuffs.

Crops on this label and other crops

for which tolerances exist for penflufen may be replanted at any

time. All other cr ops may be planted after 30 days. Prothioconazole

264-RREL PENCLO

273.5FS 6.0% penflufen

0.56 lb penflufen/gal Cotton, potato seed piece treatment Do not use for feed, food or oil purposes. Store away from feeds and

foodstuffs.

Crops on this label and other crops

for which tolerances exist for clothianidan and penflufen may bereplanted at any time. Grasses, nongrass animal feeds, dried beans and dried peas may be planted after 30 days. Do not plant any other crop in

the treated area for at least twelve

months after treated seeds are planted. Clothianidin

264-RREN PENRED 240FS 22.4% penflufen

2 lbs penflufen/gal Alfalfa, dried and succulent legume vegetables including soybean, cereal grains, and oilseeds, potatoes (seed piece treatment and in-furrow) Do not use for feed, food or oil purposes. Store away from feeds and

foodstuffs.

Registered seed treatment crops and potatoes may be replanted at any

time. All other cr ops may be planted after 30 days. NonePenflufen Hum an Health Risk Assessment D387450

Page 105 of 106 Table D.1. Penflufen End Use Products EPA Reg

No. Product Composition Labeled crops Proposed Restrictions Co-Formulants

264-RRER PENCLOTRIME

310.68FS 0.82% penflufen

0.09 lb penflufen/gal Canola, rapeseed and

mustard seed Do not use for feed, food or oil purposes. Store away from feeds and

foodstuffs.

Areas planted with treated seed may be replanted immediately with canola, cotton, corn (field, pop and sweet), cereal grains except rice, fruiting vegetables (including cucurbits), leafy vegetables (including brassica vegetables), mustard, rapeseed, sorghum, soybean, sugar beet, tuberous and corm vegetables. These areas may also be replanted after 30 days with grasses, non-grass animal feeds, and dried beans. Do not plant any other crop in the treated area for at least

four months after treated seeds are planted. Clothianidin, trifloxystrobin, metalaxyl

264-RREU PENTRI 308FS 13.3% penflufen

1.28 lb penflufen/gal Alfalfa, legume vegetables including soybeans, wheat, corn, sorghum, cotton and

rice Do not use for feed, food or oil purposes. Store away from feeds and

foodstuffs.

Crops on this label and other crops

for which tolerances exist for trifloxystrobin and penflufen may be replanted at any time. All other crops may be planted after 30 days. TrifloxystrobinPenflufen Hum an Health Risk Assessment D387450

Page 106 of 106 Appendix E. Review of Human Research

This risk assessment relies in part on data from studies in which adult human subjects were intentionally exposed to a pest icide or other chemical. Thes e studies, which comprise the Pesticide Handlers Exposure Database (PHED), the Agricultural Handler Exposure Task Force (AHETF), the Outdoor Residential Exposure Task Force (ORETF), and Seed Treatment SOPs and study MRID 47054702 have been determined to require a review of their ethical conduct, have received that review, and have been determined to be ethical.