### 1 OFFICE OF CHEMICAL
SAFETY AND
POLLUTION
PREVENTION 

### UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON D.C., 20460

PC Code: 121027

DP Barcode: 427543

Date: September 1 6

, 2015

MEMORANDUM

SUBJECT: Registration Review: Preliminary Environmental Fate and Ecological Risk

Assessment Endangered S pecies Effects Determination 

### for Methoxyfenozide

TO: Bonnie Adler, Chemical Review Manager Jill Bloom, Team Leader Linda Arrington, Branch Chief Risk Management and Implementation Branch V

Pesticide Re

- evaluation Division (7508P)

FROM: Mary Clock

- Rust, Biologist Karen Milians, Ph.D., Chemist

Environmental Risk Branch IV Environmental Fate and Effects Division (7507P )

REVIEWED

BY: T homas Steeger, Ph.D., Senior Science Advisor

Jim Carleton , Ph.D. , Senior Scientist

Environmental Risk Branch IV

Environmental Fate and Effects Division (7507P )

APPROVED

BY: Jean Holmes, DVM, MPH, Branch Chief

Environmental Risk Branch IV

Environmental Fate and Effects Division (7507P )

The Environmental Fate and Effects Division (EFED) has completed a preliminary risk assessment

for the insecticide methoxyfenozide

. EFED’s analysis has determined that the use of methoxyfenozide has the potential for direct effects on Fed erally listed threatened/endangered (hereafter referred to as “listed”) and non

- listed freshwater invertebrates following acute exposure

, and on listed and non

- listed freshwater and estuarine/marine invertebrates following chronic

exposure

. Acute risk to l isted estuarine/marine invertebrates is also possible for the majority of methoxyfenozide uses evaluated. The likelihood of direct adverse effects on birds, terrestrial

- phase amphibians, reptiles, mammals, fish, aquatic

- phase amphibians, and terrestrial an d aquatic plants

### 2 from exposure to methoxyfenozide as a result of the registered use s is expected to be low. However, the extent to which other taxa that depend on aquatic invertebrate species may be indirectly affected is uncertain. Finally, data are incomplete but available lines of evidence suggest that methoxyfenozide risk to terrestrial and aquatic plants is likely to be low.

T he potential for direct adverse effects to adult honey bee s ( Apis mellifera ) is considered low . A

review of submitted field studies on honey bee brood development and colony survival (including overwintering) do es not indicate that honey bee brood (larvae/pupae) are adversely affected by exposure to the compound , although uncertainties were noted in the subm itted toxicity data

. A recently submitted laboratory

- based acute toxicity study on larval honey bees raises new concerns. Using the new toxicity data combined with default exposure and larval food consumption rates

from the Guidance for Assessing Pesticid e Risks to Bees (US EPA, 2014) results in risk estimates that exceed EFED’s levels of concern (LOC) for honey bee larvae.

Uncertainties

Although m ethoxyfenozide is intended to act specifically on immature stages of insects within the

or d er Lepidoptera (moths/butterflies) , there is uncertainty about the extent to which larval stages
of other insects (excluding honey bees) may be affected, since the compound acts as an ecdysone agonist and is intended to induce premature molts thereby resulting in death o f the target organism

. There are also concerns for beneficial lepidopterans that co

- occur in areas where methoxyfenozide

is used.

No data are available to assess the potential for adverse effects on terrestrial plants or to aquatic vascular plants from ex posure to methoxyfenozide; however, toxicity data available for aquatic

non

- vascular plants did not indicate any adverse effects from exposure up to the solubility limit of the compound (3.3 mg/L). Also, terrestrial and vascular aquatic plant data on tebu fenozide,

another ecdysone agonist in the same chemical class as methoxyfenozide, suggest that methoxyfenozide toxicity to terrestrial and aquatic plants is likely to be low. Further, no reports of plant damage resulting from exposure to methoxyfenozide ha ve been recorded in EFED’s incident

databases. Given the mode of action of these compounds, it is uncertain whether any analogous pathways ( i.e ., ecdysone receptors) exist in plants.

For uses where the retreatment interval (RTI) was not specified, a three

- day interval was assumed. The RTI was not specified on two labels, EPA Reg, # 62719

- 442 (corn) and EPA Reg. # 62719

- 666 (peanuts).

Although whole colony studies are available for methoxyfenozide and did not demonstate any consistent long

- term advers e effects on brood development, a laboratory

- based chronic toxicity study with larval honey bees , in which exposure conditions can be more readily controlled, would

increase the confidence in risk conclusions and help to address uncertainties regarding rep eated direct exposure of larvae to methoxyfenozide. Specifically, a 21

- day larval honey bee toxicity study extending through adult emergence would be informative

.

### 3 OFFICE OF CHEMICAL
SAFETY AND POLLUTION
PREVENTION 

### UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON D.C., 20460



# Environmental Fate and Ecological Risk Assessment for Registration Review of Methoxyfenozide

.

Methoxyfenozide

CAS Registry No: 161050

- 58

- 4 PC Code: 121027

Prepared by: Mary Clock

- Rust, Biologist Karen Milians, Ph.D., Chemist U.S. Environmental Protection Agency Office of Pesticide Programs

Environmental Fate and Effects Division

Environmental Risk Branch IV 1200 Pennsylvania Ave., NW

Mail Code 7507P Washington, DC 20460 Reviewed by:

Jean Holmes D.V.M, Branch Chief Thomas Steeger, Ph.D., Senior Science Advisor

Jim Carleton , Ph.D., Senior Scientist

September 16

, 2015

### 4 Executive Summary

The preliminary risk assessment (PRA) in support of Registration Review for methoxyfenozide

, examines the risks to wildlife associated with the compound’s labeled uses. The risk assessment is based on the best available scientific and commercial information on the use, environmental fate and transport, and ecological effects of methoxyfenozide on non

- target organisms.

Methoxyfenozide is a dibenzoyl hydrazine insecticide which acts as an insect growth regulator ( IGR ) and registered for use on a variety of agricultural as well as non

- agricultural sites across the

US. The chemical is an agonist for the invertebrate molting hormone, ecdysone, and induces a precocious incomplete molt in invertebrates, particularly lepidopterans (butterflies/moths)

.

Methoxyfenozide may be applied using ground, aerial, conventional spray or chemigation applicatio n methods

. Single application rates range from 0. 16 lb a.i./A (for cotton and peanuts ) to
a maximum of 0.40 lb a.i./ A (for cotton)

. Use sites include citrus, cotton, f ruiting v egetables (Crop Group 1B) , globe artichokes, bushberries (Crop Group 13

- 07B)

, corn, peanuts, grapes, stone fruits (Crop Group 12

- 12) and tree nuts ( Crop Group 14

- 12; including almonds, walnuts, and other nuts)

. Annual maximum application rate s across all methoxyfenozide use sites do not exceed 1.0 lb

a.i./a cre /year

. The technical registrant for this pesticide is Dow AgroSciences (DAS).

The compound is considered very persistent and moderately mobile based on a soil aerobic

metabolism half

- lives range from 336 to 1100 days ; organic carbon partition coefficient ( K oc 

### )

range from 219 to 922 mL/g
oc 

### ; and, a log octanol

- water partition coefficient ( K ow 

### ) of 3.72

. O nce applied

, methoxyfenozide has the potential to move off the site of application by leaching, erosion

and runoff where it can accumulat e in aquatic systems

.

While methoxyfenozide is expected to persist in the environment and m ove to surface water via

runoff and erosion based on laboratory studies

, a monitoring s tudy was recently co mpleted which showed no apparent accumulation of methoxyfenozide in sediment and water at any of the monitoring site s under the conditions tested

. Furthermore, b ioconcentration data with both fish and invertebrates indicate that the compound does not bioconcentrate appreciably ( BCF range: 1.1

– 22.1X) and it depurates relatively quic kly once organisms are no longer exposed. Available data indicate that for both freshwater and estuarine/marine fish, the toxicity of methoxyfenozide appears limited by its solubility in water (3.3 mg a.i./L) and at this concentration, no adverse effects ( i.e ., mortality or sublethal effects) were observed on fish following acute exposure

.

EFED’s analysis has determined that all of the registered uses of methoxyfenozide have the potential to result in direct adverse effects to freshwater and estuarine/ ma rine invertebrates. Specifically, federally listed threatened/endangered (hereafter referred to as “listed”) and non

listed freshwater invertebrates are at risk following acute exposure to methoxyfenozide

, and listed

and non

- listed aquatic freshwater and e stuarine/marine invertebrates following chronic exposure

. Acute risk to listed estuarine/marine invertebrates is also possible for the majority of registered methoxyfenozide use sites that are in close proximity to these environments

. A low likelihood of

d irect adverse effects to birds, terrestrial

- phase amphibians, reptiles, mammals, fish, aquatic

- phase amphibians, and terrestrial and aquatic plants is expected from exposure to methoxyfenozide as a

### 5 result of the registered use s

. However, the re is the potential for indirect effects on taxa that depend on aquatic invertebrate species for prey and/or habitat, although the magnitude and likelihood of

indirect effects are uncertain.

There are data to indicate that lepidopteran species of terrestrial invert ebrates a re sensitive to methoxyfenozide

, consistent methoxyfenozide ’s use in controlling lepidopteran pests (such as the

corn ro ot worm, cabbage moth, diamond back moth)

. While available acute toxicity data do not indicate potential risk to adult honey be es, a laboratory

- based study indicates that larval honey bees may be sensitive to methoxyfenozide following a single (acute) exposure

. S creening

- level risk quotient (RQ) values exceed the acute risk level of concern (LOC) for honey bee larvae, although re fined RQ values based on measured residue levels in pollen/nectar are below the acute

risk LOC. F ield

- based studies of whole colonies fed methoxyfenozide

- spiked diets did not exhibit any consistent, long

- term adverse effect on brood development and/or colony ove rwintering capacity. L aboratory

- based chronic toxicity data for larval honey bees would increase the confidence in risk conclusions and address uncertainties about methoxyfenozide risk to terrestrial

invertebrates and lead to more robust risk con clusions . Specifically, a 21

- day larval bee toxicity study extend ing through adult emergence would help to address uncertainties.

1.0 Problem Formulation

The problem formulation sets the objectives for the risk assessment and provides a plan for analyzing the data and characterizing the risk (USEPA 1998a). EFED completed the preliminary problem formulation for the environmental fate, ecological risk, endan gered species, and drinking water exposure assessments to be conducted as part of the Registration Review of

m ethoxyfenozide (USEPA, 2013b).

The following section summarizes the key points of that document and discusses any differences between the analysi s outlined in the preliminary problem formulation and the analysis conducted

in this risk assessment.

1.1 N ature of Regulatory Action

The risk assessment is con ducted as part of the Agency’s Registration R eview process for pesticide active ingredients. The Registration Review process was established under the Fo od Quality Protection Act (FQPA 199 6 ).

2. Nature of Chemical Stressor

Methoxyfenozide , 3

- methoxy

- 2

- methylbenzoic acid 2

- (3,5

- dimethylbenzoyl)

- 2

- (1,1

- dimethyle thyl)hydrazide (CAS No. 161050

- 58

- 4)

, belongs to the diacylhydrazine class of insecticides that interfere with the binding of the endogenous steroidal molting hormone 20

- hydroxyecdysone with its nuclear receptor protein complex

. A s such, methoxyfenozide is referred to as an ecdysteroid (ecdysone) agonist 1



### . Exposure of sensitive organisms ( pests including fruit

worm, diamond back moth, corn root worm, leaf roller, armyworm, grapevine moth and other

1 Shimizu et al

. , 1997

.

### 6 members of the Order L epidoptera) to the compound induces a precocious incomplete molt and leads to the death of the organism

.

This assessment evaluates potential risks to non

- target species resulting from the use of methoxyfenozide products containing 22.6%, 80.0%, 23.3%, and 20.6% methoxyfenozide and correspond to the EPA Registration Numbers 62 719

- 442, 62719

- 438, 62719

- 666 and 62719

- 667, respectively.

2.2. Overview of Pesticide Usage

Data for usage was provided by OPP’s Biological and Economic Analysis Division (BEAD) and is derived from USDA National Agricultural Statistics Service (NASS; 2003

- 2010) , private pesticide market research (2003

- 2010) , and the California Department of Pesticide Reg ulation (2003

- 2010) 2 

### . The top use sites treated with methoxyfenozide are almonds (50,000 lbs per year), grapes (30,000 lbs per year), apples, lettuce, tomatoes (20,000 lbs per year), pistachios (10,000 lbs per year) and cotton (7,000 lbs per year).

Based on the submitted labels, the maximum single application rate for methoxyfenozid e is 0.40

lb a.i./acre (for cotton) , and the maximum yearly rate is 1.0 lb a.i./A ( EPA Reg. # 62719

- 438, see Appendix A ). Intrepid ® 

### can be applied by ground or aerial application equipment to most of the

crops for which it is registered (except citrus)

. Tw o end

- use products (EPA Reg. No. 62719

- 666

and 62719

- 667 ) contains methoxyfenozide (28.3% and 20.6 % ) co mbined with spinetoram and spinosad (5.66% and 10.3%, respectively ). A s ummary of u se i nformation for methoxyfenozide for all registered products can be found in Appendix A

.

2.3 Receptors

2.3.1 Aquatic and Terrestrial Effects

In ecological risk assessment, a receptor is a biological entity that is exposed to a stressor , in this case a pesticide (USEPA, 1998). Consistent with the process described in the Overview Document (USEPA, 2004), this risk assessment uses a surrogate species approach in its evaluation of methoxyfenozide . Toxicity data generated using surrogate test species, which are intended to be representative of broad taxonomic groups, are used to infer potential effects on a variety of species (receptors) included under these broader taxonomic groupings. Table 1 provides the general taxonomic groups and surrogate species tested to evaluate potential ecological effects of methoxyfenozide to broad classes of non

- target organisms. Within each of these taxonomic groups, a measure of effect is selected from among the available test data.

A cute and chronic toxicity data from studies submitte d by pesticide registrants along with the available open literature are used to evalu ate potential direct effects of methoxyfenozide on aquatic and terrestrial receptors. The open literature studies are located through EPA’s database ECOTOX

2 US EPA, 2012a.

### 7 ( http://cfpub.epa.gov/ecotox/ ), which provides a source for locating single chemical toxicity data for aquatic life, terrestrial plants, and wildlife.

Table 1 : Taxonomic Groups and Test Species Evaluated for As sessing Potential Ecological Effects of Methoxyfenozide.

Organismal Group Typical Test Species

Birds 1 Mallard duck ( Anas platyrhynchos ) Bobwhite quail ( Colinus virginianus ) Passerine (not available)

Mammals Norway rat ( Rat t us norvegicus )

Terrestrial i nvertebrates Honey bee ( Apis mellifera L. )

Freshwater fish 2 Bluegill sunfish ( Lepomis macrochirus ) Rainbow trout ( Oncorhynchus mykiss ) Fathead minnow ( Pimephales promelas )

Freshwater invertebrates Water flea ( Daphnia magna ) Midge ( Chironomus riparius )

Estuarine/marine fish Sheepshead minnow ( Cyprinodon variegatus )

Estuarine/marine invertebrates Mysid ( Americamysis bahia ) Eastern oyster ( Crassostrea virginica ) Terrestrial plants 3 Monocots

– Crop species, such as corn ( Zea mays )

Dicots

– Crop Species, such as soybean ( Glycine max ) Aquatic plants and algae Duckweed ( Lemna gibba ) Freshwater Algae ( Pseudokirchneriella subcapitata )

1 Birds are surrogates for terrestrial

- phase amphibians and reptiles.

2 Freshwater fish are surrogates for aquatic

- phase amphibians.

3 Four species of two families of monocots, one of which is corn; six species of at least four dicot families, one of which is soybeans.



### 2.3.2 Ecosystems Potentially at Risk

The ecosystems at risk are often extensive in scope; therefore, it may not be possible to identify specific ecosystems at the screening level. In general terms, terrestrial ecosystems potentially at

risk could include treated site s and areas immediately adjacent to treated site s that may receive

drift

, runoff , erosion, or discharged groundwater

. Such areas could include cultivated fields,

fencerows

, hedgerows, meadows, fallow fields or grasslands, woodlands, wetlands, riparian zone s, and other uncultivated areas.

Aquatic ecosystems potentially at risk i nclude water b odies adjacent to or down stream from treated

area s, and can include lentic systems, i.e.

, ponds, lakes and impound ments ( reservoirs )

, and lotic

systems ( streams and rivers )

. Aquatic ecosystems supplied by groundwater, including cave ecosystems and areas s upplied by seeps and springs, may be at risk from compound s that leach

into the subsurface

. For uses in coastal areas, aquatic habitat at potential risk includes marine and

estuarine ecosystems. In evaluating aquatic exposure within water bodies, EFED co nsiders the water column, benthic sediment, and pore water to all be compartments of potential concern.

2.4 Assessment Endpoints

Assessment endpoints represent the actual environmental value s that are to be protected, defined by an ecological entity (species, community, or other entity) and its attr ibute or characteristics (USEPA 1998). For methoxyfenozide , the ecological entities include the following: birds,

### 8 amphibians, reptiles, mammals, freshwater fish and invertebrates, estuarine/marine fish and invertebrates, terrestrial plants, insects, and aquatic plants and algae. The attributes assessed for each of these entities may include growth, survival, and reproduction. ( See Section 2. 6 Analysi s Plan , for further discussion).

The assessment endpoints are intended to reflect individual and population sustainability and community structure within ecosystems and hence relate back to ecosystems at risk. If risks are expected for given species/taxa based on the screening

- level assessment, then risks might be expected to translate to higher levels of biological organization.

2.5 Conceptual Model

The conceptual model used to depict the potential ecological risk associated with the proposed and existing uses of methoxyfenozide relies on previous assessments and the Agency’s current understanding of the environmental fate and ecological effects of the chemical

. Consistent with the intended use of methoxyfenozide as an insect growth regulator, p otential ri sk to non

- target terrestrial and aquatic invertebrates is expected

. Effects on invertebrates, which represent the primary consumers in an ecosystem, may result in secondary effects on other consumers. The conceptual model assumes that methoxyfenozide is capable of directly and/or indirectly affecting

terrestrial vertebrates and invertebrates and aquatic vertebrates and invertebrates, provided that environmental concentrations are sufficiently elevated as a result of proposed and existing uses

.

As described in the preliminary Problem Formulation 3 

### , t here is potentia l for adverse effects to

listed and non

- listed freshwater and estuarine/marine aquatic invertebrates following acute and/or chronic exposure to methoxyfenozide

. Also, t here is uncertainty regarding the potential effects of methoxyfenozide on larval development of terrestrial invertebrates

. Direct adverse effects to birds, mammals, fish, and terr estrial and aquatic plants are not expected; however, given the p otential for effects on aquatic invertebrate species, indirect effects to a nimals and plants are possible.

2.5.1 Risk Hypothesis

For methoxyfenozide , the following ecological risk hypothesis is employed for the ecological risk

assessment:

Given the e xisting uses of methoxyfenozide and its environ mental fate properties, there is possible acute and chronic exposure to non

- target aquatic and terrest rial organisms.
When used in accordance with the label, methoxyfenozide may result in adverse effects upon the survival, growth, and repr oduction of non

- target aquatic and terrestrial and

animals.

3 US EPA, 2013.

### 9 2.6 Analysis Plan

2.6.1. Measures of Exposure

2.6.1.1 Measures of Aquatic Exposure

M easures of exposure to aquatic animals and plants are pesticide concentrations in surface water and benthic sediment pore water simulated by the Surface Water Concentration Calculator (SWCC) to generate estimated environmental conc entrations (EECs) of methoxyfenozide that may

occur from use on crops, typically at maximum label use rates. The EECs used in risk assessment

are simulated 1

- in

- 10 year return frequency “peaks” (acute) and mean concentrations over a specified duration (chronic) generated at the modeled site, which is selected to repre sent a location expected to be more contamination

- vulnerable than most locations where the crop is grown.

2.6.1.2 Measures of Terrestrial Exposure

Terrestrial wildlife are potentially exposed to methoxyfenozide via consumption of residues on

food ite ms from spray applications on agricultural uses. For spray applications, the T

- REX model ( T errestrial R esidue EX posure model; v. 1.5. 2 ; June 6, 2013 b ) is used to predict dietary exposure to methoxyfenozide residues on foliar surfaces and insects using the Kenaga nomogram as modified by Fletcher (Hoerger and Kenaga

, 1972 ; Fletcher et al.

, 1994). In this assessment, the default foliar dissipation half

- life of 35 days was used for terrestrial modeling purposes. An example printout of the T

- REX model output is provided in Appendix D

. Exposure to terrestrial plants w as assessed using the TERR

- Plant model (version 1.2.2), a tier 1 model used to estimate

upper

- bound terrestrial plant exposure from a single pesticide application

. The results of the TerrPlant analysis are provided in Appendix E

.

Potential exposure pathways through d rinking water (imbibition) and inhalation were screened using the SIP (Screening Imbibition Program) and STIR (Screening Tool for Inhalation Risk)

prog rams , respectively , as no ted in the Problem Formulation for methoxyfenozide (US EPA, 2013b)

. R esults from the SIP tool showed th is exposure pathway to be of low concern

, i.e

., there

were no exceedances of Agency Levels of Concern (LOC). S creening using th e STIR model found inhalation exposures to be of low concern in birds and mammals

, i.e

., no LOC exceedances are expected via this potential route of exposure

. SIP and STIR are described in detail at: http://www.epa.gov/oppefed1/models/terrestrial/index.htm

.

2.6.2 Measures of Effect

Measures of effect are obtained from a suite of registrant

- submitted guideline studies which were

conducted with a limited number of surrogate test species ( Table 1 ) . The test species are not intended to be representative of the most sensitive taxa but rather were selected based on their ability to thrive under laboratory conditions. Toxicity testing reported in this risk assessment utilizes surrogate species to represent all freshwater fish (2000+) and bird (680+) species in the U.S. In addition, t he ECOTOX database 4 

### was searched in 201 4 for more ecological effects data

4 US EPA, 2009.

### 10 for methoxyfenozide. N o additional data were available that indicated greater sensitiv ity than those

embodied in the registrant

- submitted study endpoints

.

The acute measures of effect used in this screening

- level assessment are the LD 50 

### (Lethal Dose),

LC 50 

### (Lethal Concentration)

, EC 50 

### (Effects Concentration) , and IC 50 

### (Inhibition Concentration)

. These are measures of acute toxicity which result in 50% of the respective effect in tested organisms. The endpoints for chronic measures of exposure are the NOAEC (No Observed

Adverse Effects Concent ration) and the NOAEL (No Observed Adverse Effects Level). Toxicity studies were submitted for freshwater fish and invertebrates, estuarine/marine fish and invertebrates, aquatic and terrestrial plants, birds, mammals, and honey bees. The endpoints used

for risk assessment were derived from studies which underwent review and were classified as “acceptable” (conducted under guideline conditions and considered to be scientifically valid) or “supplemental” (conditions deviated from guidelines but the results are considered to be scientifically valid).

2.6.4 Integration of Exposure and Effects

The exposure and toxicity effects data are integrated in order to evaluate the risks of adverse ecological effects on non

- target species. For the risk assessment of methoxyfenozide , the risk quotient (RQ) method is used to compare estimated exposure and m easured toxicity values. The RQ method involves dividing the EEC by acute and chronic toxicity values. The resulting RQs are then compared to the Agency’s Levels of Concern (LOC s ) (USEPA 2004) ( Table 2 ). The

LOCs are used to indicate when applications o f methoxyfenozide , as directed on the label, are assumed to have the potential to cause adverse e ffects to non

- target organisms.

### 11 Table 2 : Agency Risk Quotient (RQ) Metrics and Levels of Concern (LOC) Per Risk Class.

R isk C lass R isk D escription RQ LOC

Aquatic Animals (fish and invertebrates)

Acute Potential for effects to non

- listed animals from acute

exposures Peak EEC/LC 50 1 0.5

Acute

Restricted Use Potential for effects to animals from acute exposures Risks may be mitigated through restricted use classification Peak EEC/LC 50 1 0.1

Acute Listed Species Listed species may be potentially affected by acute

exposures Peak EEC/LC 50 1 0.05

Chronic Potential for effects to non

- listed and listed animals from chronic exposures 60

- day EEC/NOAEC (fish) 1 21

- day EEC/NOAEC (invertebrates)

Aquatic Plants

Non

- Listed Potential for effects to non

- listed plants from exposures Peak EEC/LC 50 1 1

Listed Potential for effects to listed plants from exposures Peak EEC/NOAEC 1

Terrestrial Animals (mammals

, birds and invertebrates ) 2

Acute Potential for effects to non

- listed animals from acute

exposures EEC/LC 50 (Dietary) 0.5 EEC/LD 50 (Dose)

EEC/LD 50 (invertebrate) 0.4

Acute

Restricted Use Potential for effects to animals from acute exposures Risks may be mitigated through restricted use classification EEC/LC 50 (Dietary) 0.2 EEC/LD 50 (Dose)

Acute Listed Species Listed species may be potentially affected by acute

exposures EEC/LC 50 (Dietary) 0.1 EEC/LD 50 (Dose)

Chronic Potential for effects to non

- listed and listed animals from chronic exposures EEC/NOAEC 1

Terrestrial and Semi

- Aquatic Plants

Non

- Listed Potential for effects to non

- target, non

- listed plants from

exposures EEC/EC 25 1

Listed Plant Potential for effects to non

- target, listed plants from

exposures EEC/NOAEC 1 EEC/EC 05

1 LC 50 or EC 50

. 2 EEC based on upper bound Kenaga nomogram values for foliar exposure.



### 3.0 Analysis

3.1 Use Characterization

Based on the submitted labels, the maximum single application rate for methoxyfenozide is 0.06

lb a.i./acre for cotton , and the maximum yearly rate is 1.0 lb a.i./A ( EPA Reg. # 62719

- 438, Refer

to Table 3 below ). Intrepid ® 

### 2F (EPA Reg. # 62719

- 4 42) contains 22.6% a.i. and can be applied by ground or aerial application equipme nt. However although cotton has the lowest single application rate at 0.06 lbs a.i./A, the maximum number of applications annually or seasonally for

### 12 this use is not specified on the label (EPA Reg. # 62719

- 442). Summary u se i nformation for methoxyfenozide for all registered products can be found in Appendix A

.

Because methoxyfenozide is registered for use on a large number of crops , a representative set of

use sites was chosen for risk assessment purposes ( Table 3 ). The scenarios modeled in this assessment include those that have the highest application rates, as well as those that result in the highest environmental exposure concentrations (through either aquatic or terrestrial environments). A s ummary of u se i nformation for met hoxyfenozide in all registered products can

be found in Appendix A

.

Table 3: Representative Methoxyfenozide Use Sites for Ecological Risk Assessment

Use Site Single Application

Rate (lbs. a.i./A) 1 Max. No. of Application

s per year Max. Yearly Application

Rate (lbs.

a.i./A) Min. Application

Interval

(days) Application

Method EPA reg.

number

Citrus 0.25 4 1 14 Ground 62719

- 442

Cotton 0.4 1 4 1 10 Aerial and ground 62719

- 438

0.06 6 1 10 Aerial and ground 62719

- 442

Fruiting Vegetable

(Crop Group 1B) 0.25 4 1 7 Aerial and ground 62719

- 442

Globe

Artichoke 0.25 4 1 7 Aerial and ground 62719

- 442

Bush Berries 0.06 3 0.75 7 Aerial and ground 62719

- 442

0.25 3 0.75 7 Aerial and ground 62719

- 442

Corn 0.06 17 1 NS 2 Aerial and ground 62719

- 442

0.25 4 1 NS 2 Aerial and ground 62719

- 442

Peanuts 0.078 3 1 NS 2 Aerial and ground 62719

- 666

0.16 3 1 7 Aerial and ground 62719

- 666

### 13 Use Site Single Application

Rate (lbs. a.i./A) 1 Max. No. of Application

s per year Max. Yearly Application

Rate (lbs.

a.i./A) Min. Application

Interval

(days) Application

Method EPA reg.

number

Grapes 0.12 5 0.75 NS 2 Aerial and ground 62719

- 442

0.234 5 0.75 4 Aerial and ground 62719

- 666

Tree Nuts

(Almonds,

Pist a c hios,

Pecans) 0.25 2 4 1 3 Aerial and ground 62719

- 442

0.38 4 1 10 Aerial and ground 62719

- 442

0.12 8 1 8 Aerial and ground 62719

- 442

1 Cotton use presents the maximum and minimum single application rate of all the uses. Only 3 applications were assumed for the maximum single application rate of 0.40 lbs a.i./A (0.4 lbs a.i./A x 2 + 0.2 lbs a.i./A)

. 2 A three day application window was assumed as it was not specified on the label s

.



### 3.2 Exposure Characterization

3.2.1. Environmental Fate Characterization

Methoxyfenozide is non

- volatile (based on its Henry’s constant of 1.6 x10

- 9 

### atm·m 3 

### ·mole

- 1 

### ), hydrophobic (based on its octanol

- water partition coefficient: log K
ow 

### =3.72), and possesses moderate water solubility (3.3 mg/L at 25°C). M ethoxyfenozide is stable to hydrolysis (at pH s 5, 7, and 9) and photodegradation on soi l

. Based on the classification system of Goring et al. 5



### , methoxyfenozide is considered very persistent in soil with aerobic soil half

- lives ranging from 336

to 1

, 100 days. A quatic fate studies demonstrate that methoxyfenozide is also persisten t in water

under both aerobic and anaerobic conditions. T wo minor ( i.e. equivalent to l ess than 10% of applied radioactivity) transformation products (in addition to CO 2 

### ) formed in fate studies have

been identified: RH

- 117236 (3,5

- dimethylbenzoic acid N

- tert

- butyl

- N’

- (3

- hydroxy

- 2

- methylbenzoyl)hydrazide) and RH

- 131154 (3

- [N

- tert

- butyl

- N’

- (3

- methoxy

- 2

- methylbenzoyl)

- hydrazinocarbonyl]

- 5

- methylbenzoic acid (see Appendix B for structures)

.

Methoxyfenozide is characterized as mobile to moderately mobile according to the Food and Agriculture Organization United Nations scale 6



### , having soil organic carbon partition coefficients (K
oc 

### ) that rang e from 219 to 922 mL/g
oc 

### , and soil partition coefficients (K d 

### ) that rang e from 1.1 to 6.2 mL/g. Given its resistance to degradation and its mobility, methoxyfenozide h as the potential to move off the site of application by leaching, runoff and/or movement with eroded sediment, and

5 Goring et al.

, 1975

. 6 FAO, 2000.

### 14 to subsequently accumulate in aquatic systems. Table 4 provides a summary of chemical and environmental fate properties of m ethoxyfenozide.

B ecause of the chemical’s persistence, mobility, and potential to accumulate in aquatic systems,

the Agency required that a monitoring study be conducted on surface water and sediment in a representative sample of water bodies in high use areas

, to determine whether multiple years of

use would result in accumulation of methoxyfenozide residues in water and/or sediment.

M ethoxyfenozide was monitored for a t wo

- year period in two lotic (flowing) water bodies and five

lentic (standing or ponds ) water bodies in each of the following states: California, Mississippi, and Michigan and showed no apparent accumulation of methoxyfenozide in sediment at any monitoring sites

.

In Terrestrial Field Dissipation (TFD) studies performed on sand (WA and GA), loamy sand (CA), and loam (TX) soils, methoxyfenozide applied to fields dissipated with DT 50 

### s ( the amount of time for 50% dissipation of the parent) ranging from 92 days to 327 days. Methoxyfenozide was

detected as deep as 36 inch es in the soil in these studies, at concentrations up to 0.039 mg/kg soil

, providing evidence of leaching. Metabolites in these studies were not identified. Thus, results from

the TFD studie s are consistent with those from the laboratory fate studies, suggesting high persistence in the terrestrial environment and the potential for leaching to ground water.

In a bioconcentration study on juvenile bluegill sunfish ( Lepomis macrochirus ), BCFs (bioconcentration factors) were 1.1x for fillet, 22.1x for viscera, and 10.5x for whole fish tissues; the majority (84

- 94%) of residues depurated by 14 days. Based on these data

, methoxyfenozide does not appear to significantly bioconcentrate in fish

. To address lingering uncertainty about the chemical’s bioconcentration potential in other aquatic animals , the registrant submitted a bioconcentration study using the freshwater clam ( Corbicula fluminea ). The re sults of this study indicate that methoxyfenozide did not bioconcentrate extensively in invertebrates . When placed in untreated water, the clam s depurate d methoxyfen ozide by 95% in roughly 16 days

. Although the parent compound has a log octanol

- water part ition coefficient (K
ow 

### ) of 3.72 and might be expected to bioconcentrate, the relatively low measured BCF coupled with the rapid depuration of the compound suggests that methoxyfenozide is metabolized in fish and clams to more polar compounds and readily ex creted.

Table 4 : Chemical P roperties and Environmental Fate Parameters of Methoxyfenozide.

Parameter Value Description Reference

Chemical Classification Diacylhydrazine

--

Molecular Formula C 22 H 28 N 2 O 3 --

PC Code 121027

--

Chemical Name (IUPAC) n

- tert

- butyl

- N’

- [2

- methyl

- 3

- methoxybenzoyl]

- 3,5

- dimethylbenzohydrazide --

Chemical Name (CAS) 3

- methoxy

- 2

- methylbenzoic acid 2

- (3,5

- dimethylbenzoyl)

- 2

- (1,1

- dimethylethyl)hydrazide --

### 15 Parameter Value Description Reference

CAS Number 161050

- 58

- 4

--

Pesticide Classification Insecticide

--

USEPA, 2000 Molecular Weight 368 g/mol

--

Physical State white powder

--

Water Solubility (ppm) 3.3 at 2 5 o C Moderately soluble

Vapor pressure (25 o C) 2.0 x 10

- 8 torr Not likely to volatilize from dry surfaces

Henry's Law Constant 1.62 x10

- 9 atm

· m 3

· mole

- 1 (Calculated) Not likely to volatilize

from water or wet

surfaces

Octanol/Water Partition, K

ow 5248 (log K

ow = 3.72 ) Hydrophobic

- potential

to bioaccumulate

Persistence

Hydrolysis Stable at pH levels of 5, 7, and 9 in a 30 day study period No degradation

observed MRID 441444

- 30

Direct photolysis in

water at pH 7 t 1/2 = 77 days at pH 6.6 in pond water. Degradates were not identified, but were present at <5% of the AR (up to 7 degradates) Moderately persistent

to pers istent. Studies suggest that photolysis in water is

not an important degradation pathway MRID 441444

- 31

Stable in aqueous buffer solution (pH 7)

Degradate RH

- 131 154 was present at
≤0.56% in irradiated and dark samples MRID 44617805

Photolysis on soil Stable Degradate RH

- 13 1154 was present at

< 2.0% of the AR in irradiated and dark samples. Persistent

Studies indicate that photolysis on soil is not an important degradation pathway MRID 446178

- 06

Aerobic soil

metabolism t 1/2 = 1100 days (loamy sand) Persistent Studies exhibited poor

extraction of the solid phase and/or loss of 14 C

over time. MRID 446178

- 07

t 1/2 = 336 and 722 days in loamy sand and sandy clay loam , respectively. MRID 446178

- 08

t 1/2 = 573 days (loam soil) MRID 441444

- 32

Anaerobic aquatic

metabolism t 1/2 = 654 days Persistent Poor extraction, and redox and pH

information was not

submitted MRID 446178

- 10

Aerobic aquatic

metabolism t 1/2 = 963 days and 3 8 7 days in aerobic flooded sandy loam and clay soils, respectively Persistent MRID 446178

- 09

Field Dissipation

Terrestrial field

dissipation t 1/2 = 327 days ( sand soil, WA ) Persistent MRID 446178

- 11

t 1/2 = 139 days (loamy sand, CA),

151 days (sand soil, GA) , and 92 days (loam soil, TX) Dissipates slowly in the

environment and leaching was observed (maximum depth of 3 6 inches) MRID 446178

- 12

### 16 Parameter Value Description Reference
Mobility

Leaching and absorption/desorption K
oc and K d in mL/g

267 and 4.2

, loam soil

922 and 1.1

, loamy sand

678 and 1.2

, loamy sand

219 and 6.2, loam soil

365 and 3.8, silt loam Mobile to moderate ly

mobil e MRID 441444

- 3 3

Fish Bioconcentration

Bioconcentration in fish (BCF) 1.1

- 1.3 x fo r fillet, 16.6

- 22.1x for viscera,

and 9.9

- 10.5x for whole fish tissues Relatively Low BCF MRID 446178

- 13

AR=Applied Radioactivity Classification of persistency was based on Goring scale, 1975. Mobility was described using Swann et al. scale, 1983.

t 1/2 =Half

- life



### 3.2.1.1 Residues of Concern

The only residue of concern at this time is the parent chemical, methoxyfenozide. The predominant degradates of methoxyfenozide are RH

- 117236 and RH

- 131154 (See Appendix B for structures), however these were found only in low relative amounts (1

– 6.7% of applied radioactivity) in the

environmental fate studies.

3.2.2 Measures of Aquatic Exposure

3.2.2.1 Model Inputs

The EECs for surface water were generated using the Surface Water Concentration Calculator (SWCC v

. 1.106 ). Table 5 list the input parameters used in aquatic exposure modeling for methoxyfenozide.

Chemical property model input values were chosen in accordance with EFED’s current input parameter guidance 7 

### . The upper 90% confidence limit on the mean half

- life (960 d) was selected to represent aerobic soil metabolism in SWCC and t he mean K oc 

### value was used . Methoxyfenozide

was modeled as stable to both hydrolysis and photolysis. The upper 90% confidence limit on the

mean half

- life (1,5 59 d) was selected to represe nt aerobic aquatic metabolism.

Table 5 : SWCC Input Parameter Values for Methoxyfenozide Uses 1

Input Parameter Value Source Comment

Organic Carbon Partition Coefficient (K

oc ) (L/kg

oc ) 490 MRID 441444

- 33 Represents the average K

oc .

Aerobic Soil Metabolism

Half

- life (days) 960 MRIDs 446178

- 08,

446178

- 07, 441444

- 32 Represents the 90 percent confidence

bound on the mean half

- life.

7 US EPA, 2009.

### 17 Input Parameter Value Source Comment

Aerobic Aquatic

Metabolism Half

- life (days) 1559 MRID 446178

- 09 Represents the 90 percent confidence

bound on the mean half

- life.

Anaerobic Aquatic

Metabolism Half

- life (days) 1962 MRID 446178

- 10 Input value is 3X the measured half

- life to account for uncertainty in using a single data point

Hydrolysis Half

- lives (days) 0 MRID 441444

- 30 Stable

Aqueous Photolysis

Half

- life (days) 0 MRID 446178

- 05 Stable

1 Parameters are selected as per Guidance for Selecting Input Parameters in Modeling the Environmental Fate and Transport of Pesticides; Version 2.1, October 22, 2009.



### Although there is little evidence of p otential bioaccumulation of methoxyfenozide in aquatic organisms 8



### , because methoxyfenozide has a log K
ow 

### of 3. 72

, an additional exposure pathway that is considered in this assessment is the consumption of contaminated fish or aquatic invertebrates that have residues of methoxyfenozide from uptake from the water and diet. The potential risk from this pathway is ev aluated and discussed further in the “Risk Description” section of the document. Multiple lines of evidence will be used to evaluate bioaccumulation potential, including measured bioconcentration factors (BCF), bioaccumulation factors (BAF) and a food web bioaccumulation model ( KABAM 9



### , the K ow 

### - Based Aquatic Bioaccumulation Model) . The bioaccumulation assessment relies on predicted water and sediment concentrations from SWCC to estimate concentrations of methoxyfenozide in the tissues of aquatic organisms. In order to evaluate potential risk, these estimated tissue concentrations will be compared to toxicity values for various taxonomic groups that may consume aquatic organisms. The current version of KABAM estimates risks only to terrestrial birds and ma mmals consuming aquatic prey.

3.2.2.2 Selection of Crops and Scenarios

Fifteen standard scenarios were used in the modeling uses: Florida (FL) citrus, M ississippi (MS)

cotton, North Carolina (NC) cotton, California ( CA ) almonds, FL tomato, FL pepper, CA lettuce, Georgia ( GA ) pecans, New York ( NY ) grapes, MS corn, NC peanut, Oregon ( OR ) berries OP, FL turf, and OR grass seed ( Table 6 )

. Aerial application was used for each of the modeling scenarios

because i t results in more conservative estimates ; however, for citrus , ground application was modeled since aerial applications are not permitted

. A pplication rate s and retreatment intervals

w ere obtained from the Int r e pid ® 

### 2F label 10 

### ( Table 6 )

. The retreatment interval represents the

minimum amount of time allowed between pesticide reapplications

. For uses where the retreatment

interval was not specified, a three day interval was assumed. The application dates for these

scenarios were chosen acco rding to their crop profiles, crop lifecycle and/or time when heavy pest pressure i s likel y to occur 11 

### ( Table 6 )

.

8 In a bioaccumulation study with juvenile bluegill sunfish ( Lepomis macrochirus ), BCFs were 1.1x for fillet, 22.1x for viscera, and 10.5x for whole fish tissues; the majority (84

- 94%) of residues depurated by 14 days.

9 http://www.epa.gov/oppefed1/models/water/kabam/kabam_user_guide.html

10 Int repid Master Label, 2013.

11 USDA Crop Profiles. Available online at: http://www.ipmcenters.org/cropprofiles/CP_form.cfm

### 18 The CA lettuce scenario was used as a proxy in modeling the globe artichoke use, because globe

artichoke s are grown almost exclusively in Cali fornia

, and specifically in the Monterey area where CA lettuce is grown. The application rate of 0.25 lb s a.i./acre as well as the retreatment interval of seven days were obtained from the label. T here is no standard scenario for use on bushberries ; therefore

, the OR berries OP (organophosphate) scenario was used because it provides the closest approximation to bushberries among the approved scenarios. The application dates for the scenarios were chosen according to their crop profiles, crop lifecycl e and/or time when heavy pest

pressure was likel y to appear . The highest application rates for methoxyfeno z ide were assessed, which represent both the Intrepid ® 

### 2F label and Intrepid ® 

### 80 WSP (water soluble pouch)

.

Environmental f ate

- related input values were chosen for modeling, in accordance with current input parameter guidance 12



### . The upper 90% confidence bound on the mean was selected for the

aerobic soil metabolism half

- life (960 d ays ) input for surface water

, as per current input parame ter guidance for th is model. H ydrolysis and photolysis were modeled as stable

. T he upper 90% confidence bound on the mean was selected for the aerobic aquatic metabolism half

- life (1559

d ays ) input, and 3 times the single available anaerobic aquatic metabolism half

- l ife was used to represent degradation occurring within the benthic sediments

.

Table 6 : SWCC Application

- Specific Input Parameters for Methoxyfenozide.

Uses PRZM

Scenario Max App rate (lbs

ai/A) # Apps Interval (days) % Drift/ Efficiency Date of 1 st 

### of application

Citrus FL citrus 0.25 4 14 0.062/0.9 9 April 1 st

Cotton 1 NC cotton 0.40 3 10 0.125/0.95 July 18 th

NC cotton 0.40 3 10 0.125/0.95 July 18 th

MS cotton 0.40 3 10 0.125/0.95 July 18 th

Fruiting vegetables FL tomato 0.25 4 7 0.125/0.95 April 1 st

FL pepper 0.25 4 7 0.125/0.95 April 1 st

Globe

Artichoke CA lettuce 0.25 4 7 0.125/0.95 April 16 th

CA lettuce 0.25 4 7 0.125/0.95 April 16 th

Bushberries OR berries 0.06 3 7 0.125/0.95 March 24 th

OR berries 0.25 3 7 0.125/0.95 March 24 th

Grass, forage fodder hay OR Grass seed 0.07 8 3 assumed 0.125/0.95 July 18 th

FL turf 0.07 8 3 assumed 0.125/0.95 July 18 th

Peanuts NC peanut 0.078 3 3 assumed 0.125/0.95 Aug 16 th

NC peanut 0.16 3 7 0.125/0.95 Aug 16 th

12 US EPA, 2009.

### 19 Uses PRZM

Scenario Max App rate (lbs

ai/A) # Apps Interval (days) % Drift/ Efficiency Date of 1 st 

### of application

Corn 2 MS corn 0.06 17 Assumed 3 assumed 0.125/0.95 Jun 10

MS corn 0.25 4 Assumed 3 assumed 0.125/0.95 Jun 10

Grapes 2 NY Grapes 0.12 5 3 assumed 0.125/0.95 May 22 nd

NY Grapes 0.234 5 4 0.125/0.95 May 22 nd

Tree nuts Crop group 14 (Almond, pistachios) CA almond 0.25 4 3 0.125/0.95 July 16 th

CA almond 0.38 4 10 0.125/0.95 July 16 th

GA Pecans 0.12 8 8 0.125/0.95 May 1 st

1 Cotton use presents the maximum and minimum single application rate of all the uses. Only 3 applications were assumed for the maximum single application rate of 0.40 lbs a.i./A (0.4 lbs a.i./A x 2 + 0.2 lbs a.i./A)

. 2 Interval was not specified therefore, a 3 days interval was assumed. Although methoxyfenozide is not registered for use on grapes in NY, this scenario was used for modeling purposes.



### 3.2.2.3 Surface Water

The methoxyfenozide surface water EECs for representative use sites are listed below in Table 7

. The highest EECs were for cotton

, with an acute ( peak ) value of 185 μg/L (parts per billion; ppb )

and chronic values slightly lower than this

. ( Note that because methoxyfenozide is persistent to degradation, concentrations increase year over year in the modeled farm pond. If use of methoxyfenozide is discontinuous over a 30 year period of simulation, EECs can be expected to be less than those rep orted).

Table 7 : Estimated Surface Water Environmental Concentrations (EECs) for Current Uses of Methoxyfenozide.

USE SCENARIO (PRZM scenario used; rate modeled in kg/ha) 

### Estimated Environmental Concentrations (EECs, ppb)

Application

Method Peak 96

- hour 21

- day 60

- day

Citrus FL citrus; 0.28 x 4 applic. @ 14

- d

interval ground 22.7 22.6 22.4 22.1

Cotton 1 NC cotton; 0.45 x 2 (applic.)+ 0.22 x 1 applic.

@ 10

- d interval aerial 185 185 183 182

NC cotton; 0.07

x 6 (applic.) @

10

- d interval aerial 48.4 48.3 47.8 47.4

MS cotton; 0.45

x 2 (applic.)+ 0.22 x 1 applic.

@ 10

- d interval aerial 120 119 118 117

Fruiting Vegetables FL tomato, 0.28 x 4 applic @ 7

- d

interval aerial 119 119 118 116

FL pepper, 0.28 x 4 applic @ 7

- d

interval aerial 135 134 133 130

### 20 USE SCENARIO (PRZM scenario used; rate modeled in kg/ha) 

### Estimated Environmental Concentrations (EECs, ppb)

Application

Method Peak 96

- hour 21

- day 60

- day

Globe

Artichoke CA lettuce, 0.28 x 4 applic @ 7

- d

interval aerial 144 144 143 142

Grass, forage fodder hay OR Grass seed x 8 applic @ 3

- d

interval aerial 37.4 37.3 37.1 36.7

FL turf, 0.07 x 8

applic @ 3

- d

interval aerial 20.5 20.4 20.2 19.9

Bushberries OR berries, 0.07 x 3 applic @ 7

- d

interval aerial 13.2 13.1 13.0 12.9

OR berries, 0.28 x 3 applic @ 7

- d

interval aerial 52.7 52.6 52.2 51.6

Peanuts NC peanuts, 0.09 x 3 applic @ 3

- d

interval aerial 27.6 27.6 27.4 27.0

NC peanuts, 0.18

x 3 applic @ 7

- d

interval aerial 54.5 54.4 54.0 53.4

Corn MS corn, 0.07 x 17 applic @ 3

- d

interval aerial 144 144 143 14 1

MS corn, 0.28 x 4 applic @ 3

- d

interval aerial 130 130 127 127

Grapes 2 NY grapes, 0.13

x 5 applic @ 3

- d

interval aerial 63.9 63.8 63.5 63.1

NY grapes, 0.26 x 5 applic @ 4

- d

interval aerial 141 141 140 139

Tree nuts (almond, pistachio) CA almond, 0.25 x 4 applic @ 3

- d

interval aerial 66.0 65.8 65.3 64.3

CA almond, 0.43 x 4 applic @ 10

- d interval aerial 101 101 100 99

GA pecans, 0.13 x 8 applic @ 8

- d

interval aerial 72.3 72.1 71.7 70.7

1 Refer to the modeling results for NC cotton scenario in Appendix F

2 Although methoxyfenozide is not registered for use on grapes in NY, this scenario was used for modeling purposes.

Bolded value represents the highest EDWC for methoxyfeno zide



### 3.2.2. 4 Aquatic Exposure Monitoring

Methoxyfenozide was not included in monitoring conducted by the U. S. Geological Survey (USGS) National Water Quality Assessment (NAWQA) program nor in the California Department of Pesticide Regulation (CDPR) Surface Water Database (CDPR 200 3 ).

### 21 Because m ethoxyfenozide is very persistent, moderately mobile and may accumulate in the aquatic environment following repeated applications, the Agency recommended surface water and

sediment stud ies using a representative sample of water bodies in high use areas (based on DAS record sales, growers and state and county government records) . These studies were intended to determine whether multiple years o f use would result in evidence of accumulation of methoxyfenozide residues in water and/or sediment in areas that represent vulnerable fields (prone to runoff)

. Samples for determining methoxyfenozide resid ues were collected over a two

- year period (2012 a nd 2013) in two lotic (flowing) water bodies and five lentic (standing) water bodies in each of the following states: California, Mississippi, and Michigan.

The maximum concentration of methoxyfenozide detected in lotic surface water samples was 1.31

μg /L, found in Mississippi

. The maximum concentration detected in lentic waters was 0.845 μg/L

, in a pond in Michigan. The maximum concentration of methoxyfenozide in benthic sediment s (31 μg/kg) was detected in Michigan. No apparent accumulation of methoxyfenozide was observed in

sediment at any monitor ing sites after years of use

. There are deficiencies of the monitoring study such as analytical methods slightly modified (ECMs reported in the study differed from the one submitted to the Agency) and one sampling site was changed with an alternate sampling point.

It may not be appropriate to make a direct comparison from the results of the monitoring study

with the values obtained in modeling (using SWCC) because the freq uency of sampling in the monitoring study may not have captured the peak concentration

. Additionally, SWCC model simulates the impact of daily weather on the treated agricultural field, and resulting concentrations in an adjacent farm pond over a defined period (here, thirty years). During this time, pesticide is

washed

- off of the field into the water

- body by twenty to forty rainfall/runoff events per year. Each new addition of pesticide mass from each runoff event adds to the existing pesticide mass in the pond from previous runoff and/or spray

- drift events. Since methoxyfenozide is known to be

pers istent in aquatic environments, the mass of the pesticide accumulates in the pond from one year to the next. In the SWCC model, the yearly simulated peaks are not independent of each other but are temporally auto

- correlated, meaning that the “1

- in

- 10 year EECs” obtained fro m model

post

- processing are in part functions of the simulation duration. As a result, SWCC results likely overestimate concentrations in streams and various other kinds of water bodies, as over the course of thirty years, some loss of methoxyfenozide is e xpected due to washout, dispersion, burial of sediment and other dissipative processes that aren’t simulated. In particular, methoxyfenozide concentrations in lotic (flowing) water bodies are not expected to accumulate at such a high concentrations from ye ar to year because o f downstream advective removal. Table 8 below details the results of the monitoring study conducted by DAS.

Table 8 : Summary of the Methoxyfenozide Sediment and Surface Water Monitoring Study

Site Concentration of methoxyfenozide in surface water (μg/L), (Number of samples analyzed) Concentration of methoxyfenozide in sediment (μg/kg), (Number of samples analyzed)

Lotic Lentic Lotic Lentic

California ND

- 1.01 (88) 1 ND

- 0.0502 (20) ND (8) ND (20)
Mississippi ND

- 1.31 (55) 2 ND

- 0.233 (20) ND (8) ND (20)

### 22 Michigan ND (36) 3 ND

- 0.845 (23) ND (4) ND

- 31.0 (23)

LOQ=0.050 μg/L and LOD= 0.015μg/L in surface water and LOD= 3 μg/kg in sediment.

ND =below detection limit

1 87, 7

- day composite samples and 1, 28

- day composite sample

2 47, 7

- day composite samples and 8, 28

- day composite samples

3 22, 7

- day composite samples and 14, 28

- day composite samples



### OPP is not aware of any other monitoring programs in which methoxyfenozide is an analyte.

3.2.3 Measures of Terrestrial Exposure

Exposure to terrestrial organisms was assessed based on the registered uses of methoxyfenozide. Dietary e xposure to birds and mammals was assessed using the T

- REX model 2



### . Terrestrial plant exposure was estimated using the TerrPlant model 13



### .

3.2.3.1. Ingestion of Foliar Residues by Birds and Mammals

Terrestrial wildlife exposure estimates are typically calculated for the dietary exposure of birds

and mammals. Avian exposures are considered surrogates for exposures to terrestrial

- phase amphibians and reptiles. Fo r exposure to terrestrial organisms, such as birds and mammals, pesticide residues on food items are estimated, based on the assumption that organisms are exposed to pesticide residues in a given exposure use pattern. For methoxyfenozide, application meth ods for the registered uses include aerial, broadcast, banded, and directed spray of liquid formulations for all crops.

T

- REX 14 

### (Version 1. 5

. 2 ) is used to calculate upper

- bound dietary EECs for estimating exposure

to birds and mammals resulting from the registered use s of methoxyfenozide. A one year time period is simulate d, and t he default foliar dissipation half

- life of 35 days was used for modeling

the registered uses. An example printout from the T

- REX model is provided in Appendix D

.

Table 9 : Input Parameters for Deriving Terrestrial EECs for Methoxyfenozide Labeled Uses (T

- REX).

Use Site Application Rate (lbs a.i./A) Minimum Reapplication Interval (days) 1 Number of Applications

Citrus 0.25 14 4

Cotton 3 0.4 10 4

Fruiting Vegetables 0.25 7 4

Globe Artichoke s 0.25 7 4

Bushberries 0 .25 7 3

Corn 0.25 NS 2 4

Peanuts 0.16 7 3

13 http://www.epa.gov/oppefed1/models/terrestrial/index.htm

14 USEPA. 2014. T

- REX Version 1.5.2 (Terrestrial Residue Exposure). http://www.epa.gov/oppefed1/models/terrestrial/#trex (last accessed 0 2 .2 4 /1 5 )

### 23 Use Site Application Rate (lbs a.i./A) Minimum Reapplication Interval (days) 1 Number of Applications

Grapes 0.234 4 5

Tree Nuts 0.38 10 4

1 TREX v 1.5.2 allows for the input of applications with varying retreatment intervals. Where multiple values are entered, the second interval represents an application that occurs outside the growing season, but still presents the potential for exposu re. 2 A three

- day re

- application interval was assumed as it was not specified on the label.

3 For the maximum single application rate of 0.40 lbs a.i./A , two applications of 0.4 lb a.i./acre plus one application of 0.2 lb

a.i./acre were assumed (0.4 lbs a.i./A x 2 + 0.2 lbs a.i ./A).



### Differences in exposures between ground and aerial applications are not assessed with the current

T

- REX model. Therefore, terrestrial risk conclusions for the registered uses apply to both ground and aerial exposures resulting from application of methoxyfenozide

. Dose

- based EECs for birds and mammals range from a low of 115 mg/kg

- bw for exposure to small birds from methoxyfenozide use on peanuts to a high of 333 mg/kg

- bw for exposure to small birds from use on tree nuts. Dietary EECs for birds and mammals range from a low of 6.31 mg/kg diet for fruits/pods/seeds from methoxyfenozide use on peanuts to a high of 292 mg/kg diet for short grass

from use on cotton ( Table 10 ). Uncertainties in the terres trial EECs are primarily associated with

a lack of data on pesticide spray interception and subsequent dis sipation from foliar surfaces. An example of output from the T

- REX model is provided in Appendix C

.

Table 1 0 : T

- REX Calculated EECs as Food Residu es for Terrestrial Animals from Methoxyfenozide Labeled Uses.

Food Type Dietary

Based (ppm) (mammals and birds) Dose Based (mg/kg

- bw) (birds) Dose Based (mg/kg

- bw) (mammals)

All Size

Classes Small (20 g) Medium (100 g) Large (1000 g) Small (15 g) Medium (35 g) Large (1000 g)

Citrus (4 appl. @ 0.25 lb a.i./acre , 14

- day RTI, 1 lb a.i./acre/year)

Herbivores/Insectivores Short grass 166 189 108 48.3 158 109 25.4 Tall grass 76.1 86.7 49.4 22.1 72.6 50.1 11.6 Broadleaf plants 93.4 106 60.6 27.2 89.1 61.6 14.3 Fruits/pods/ seeds 10.4 11.8 6.7 3.0 10.0 6.8 1.59 Arthropods 65.0 74.0 42.2 1 8.9 62.0 42.9 9.94
Granivores

Seeds N/A 2.63 1.50 0.67 2.20 1.52 0.35
Cotton (3 appl. ( 2@0.4 lb a.i./acre+1@0.2 lb a.i./acre), 10

- day RTI, 1 lb a.i./acre/year)

Herbivores/Insectivores Short grass 292 333 190 85.0 279 193 44.7 Tall grass 134 153 87.0 39.0 128 88.3 20.5 Broadleaf plants 164 187 107 47.8 157 108 25.1 Fruits/pods/ seeds 18.3 20.8 11.9 5.31 17.4 12.0 2.79 Arthropods 115 130 74.4 33.3 109 75.5 17.5

Granivores Seeds N/A 4.62 2.64 1.18 3.87 2.68 0.62 Fruiting Vegetables , Globe Artichokes (4 appl. @0.25 lb a.i./acre, 7

- day RTI, 1 lb a.i./acre/year)

### 24 Food Type Dietary

Based (ppm) (mammals and birds) Dose Based (mg/kg

- bw) (birds) Dose Based (mg/kg

- bw) (mammals)

All Size

Classes Small (20 g) Medium (100 g) Large (1000 g) Small (15 g) Medium (35 g) Large (1000 g)

Herbivores/Insectivores Short grass 197 225 128 57.4 188 130 30.1 Tall grass 90 103 58.7 26.3 86.2 596 13.8 Broadleaf plants 111 126 72.1 32.3 106 73.1 17.0 Fruits/pods/ seeds 12.3 14.0 8.01 3.59 11.8 8.13 1.88 Arthropods 77.3 88.0 50.2 22.5 73.7 50.9 11.8
Granivores
Seeds N/A 3.12 1.78 0.80 2.61 1.81 0.42
Bushberries (3 appl. @0.25 lb a.i./acre , 7

- day RTI, 0.75 lb a.i./acre/year)

Herbivores/Insectivores

Short grass 158 180 102 45.9 150 104 24.1 Tall grass 72.3 82.3 46.9 21.0 68.9 47.6 11.0 Broadleaf plants 88.7 101 57.6 25.8 84.6 58.5 13.6 Fruits/pods/ seeds 9.86 11.2 6.40 2.87 9.40 6.49 1.51 Arthropods 61.8 70.4 40.1 18.0 58.9 40.7 9.44
Granivores
Seeds N/A 2.49 1.42 0.64 2.09 1.44 0.33
Peanuts (3 appl. @0.16 lb a.i./acre , 7

- day RTI, 1 lb a.i./acre/year)

Herbivores/Insectivores Short grass 101 115 65.6 29.4 96.2 66.5 15.4 Tall grass 46.3 52.7 30.0 13.5 44.1 3 0.5 7.07 Broadleaf plants 56.8 64.7 36.9 16.5 54.1 3 7.4 8.67 Fruits/pods/ seeds 6.31 7.18 4.10 1.83 6.01 4.16 0.96 Arthropods 39.5 45.0 25.7 11.5 3 7.7 26.1 6.04
Granivores
Seeds N/A 1.60 0.91 0.41 1.34 0.92 0.21 Corn (4 appl. @0.25 lb a.i./acre , 3

- day RTI 1 , 1 lb a.i./acre/year)

Herbivores/Insectivores Short grass 220 251 143 64.0 210 145 33.6 Tall grass 101 115 65.5 29.3 96.1 66.5 15.4 Broadleaf plants 124 141 80.4 36.0 118 81.6 18.9 Fruits/pods/ seeds 13.8 15.7 8.93 4.00 13.1 9.06 2.10 Arthropods 86.2 98.1 56.0 25.1 82.2 56.8 13.2
Granivores
Seeds N/A 3.48 1.98 0.89 2.91 2.01 0.47 Grapes ( 4 appl: 3@0.234 lb a.i./acre+1@0.05 lb a.i./acre, 4

- day RTI, 0.75 lb a.i./acre/year)

Herbivores/Insectivores Short grass 156.10 177.78 101.38 45.39 148.82 102.86 23.85 Tall grass 71.54 81.48 46.46 20.80 68.21 47.14 10.93 Broadleaf plants 87.80 100.00 57.02 25.53 83.71 57.86 13.41 Fruits/pods/ seeds 9.76 11.11 6.34 2.84 9.30 6.43 1.49 Arthropods 61.14 69.63 39.71 17.78 58.29 40.29 9.34
Granivores
Seeds N/A 2.47 1.41 0.63 2.07 1.43 0.33

### 25 Food Type Dietary

Based (ppm) (mammals and birds) Dose Based (mg/kg

- bw) (birds) Dose Based (mg/kg

- bw) (mammals)

All Size

Classes Small (20 g) Medium (100 g) Large (1000 g) Small (15 g) Medium (35 g) Large (1000 g)

Tree Nuts (3 appl: 2@0.38 lb a.i./acre+1@0.24 lb a.i./acre, 10

- day RTI, 1 lb a.i./acre/year)

Herbivores/Insectivores Short grass 193.79 220.70 125.86 56.35 184.76 127.70 29.61 Tall grass 88.82 101.16 57.68 25.83 84.68 58.53 13.57 Broadleaf plants 109.01 124.15 70.79 31.70 103.93 71.83 16.65 Fruits/pods/ seeds 12.11 13.79 7.87 3.52 11.55 7.98 1.85 Arthropods 75.90 86.44 49.29 22.07 72.36 50.01 11.60
Granivores
Seeds N/A 3.07 1.75 0.78 2.57 1.77 0.41

1. RTI=Retreatment interval (days)

2. RTI not stated on label, therefore, a 3

- day RTI was assumed.



### 3.2.3.2. Exposure to Terrestrial Invertebrates

A s tud y o f methoxyfenozide residues in honey bee colonies following treatment of almond trees with methoxyfenozide was submitted by the registrant and has been reviewed . In this study consisting of two trials , a l mond tree s in full bloom were treated with the methoxyfenozide formulated product Intrepid ® 

### 240 SC (24% a.i. , no longer registered ) in order to quantify residue levels of methoxyfenozide in pollen, nectar, and larval honey bees (MRID 489622 02)

. Specificall y, t he study measured methoxyfenozide levels in pollen and nectar collected by bees,

present inside larvae, and in pollen and nectar from almond flowers following an application of Intrepid ® 

### 240 SC while bees were actively foraging

. Residue levels in royal jelly

, wax and honey

were not measured

. The results indicate that when applied at a rate of 0.19 lb a.i./acre ( roughly half the maximum application rate of 0.38 lb a.i./acre for tree nuts), residues of methoxyfenozide

were measured in bee

- collected p ollen (corbicular pollen) at up to 9.42 mg a.i./kg (ppm) ; residues in nectar (collected from the honey stomach s of forager bees) were roughly an order of magnitude lower ( i.e ., maximum detected was 0.794 mg a.i./kg) than what was detected in pollen

. R esidu es were also detected in developing brood and ranged from <0.005 to 0.021 mg a.i./kg

. Compared to peak residues measur ed in corbicular pollen on the day of application , residues at 12 days after application had declined by 19

- fold in Trial 1 and 636

- fold i n Trial 2. In both trials, residues in comb pollen peaked on Day 1 after treatment; by 19 days after treatment, residues in comb pollen had declined by a factor of 101

- fold in Trial 1 and by a factor of 1.2 in Trial 2. The difference in

the extent of decli ne measured in the two studies may be associated with the differences in pollen

tree strains used combined with the differences in weather at the two sites

.

3.2.3.3. Residues in Aquatic Food Items for Mammals and Birds

The KABAM model (K OW 

### (based) Aquatic BioAccumulation Model) version 1.0 was used to evaluate the potential exposure and risk of direct effects to birds and mammals via bioaccumulation and biomagnification in aquatic food webs. KABAM is used to estimate

### 26 potential bioaccumulat ion of hydrophobic organic pesticides in freshwater aquatic ecosystems and risks to mammals and birds consuming aquatic organisms which have bioaccumulated these pesticides. The bioaccumulation portion of KABAM is based upon work by Arnot and Gobas (2004) who parameterized a bioaccumulation model based on PCBs and some pesticides ( e.g ., lindane, DDT) in freshwater aqua tic ecosystems (Arnot and Gobas, 2004) . KABAM relies on a

chemical's octanol

- water partition coefficient (K OW 

### ) to estimate uptake and elimination constants through respiration and diet of organisms in different trophic levels. Pesticide tissue residues are calculated for organisms at different levels of an aquatic food web. The model then uses pesticide

tissue conce ntrations in aquatic animals to estimate dose

- and dietary

- based exposures and associated risks to mammals and birds (surrogate for amphibians and reptiles) consuming aquatic organisms. Seven different trophic levels including phytoplankton, zooplankton, benthic invertebrates, filter feeders, small

- sized (juvenile) forage fish, medium

- sized forage fish, and larger piscivorus fish, are used to represent an aquatic food web. Importantly, chemical metabolism by biota is assumed to be zero in KABAM unless evi dence indicates such metabolism is likely to affect the model predictions substantially. Measured BCF values are lower than what would be expected based on methoxyfenozide ’ s log K OW 

### of 3.72 . Input scenarios and parameters were chosen to represent the rang e of exposures from high to low and are presented in Table 11

. An e xample output from the bioaccumulation model is provided in Appendix G

.

Table 11

. Bioaccumulation Model Input Values for Methoxyfenozide

.

Parameter Input Value Source

Pesticide Name Methoxyfenozide

-- Log K OW 3.72 USEPA, 2000

K OC 490 Mean K OC value from MRID 441444 33

. Pore water EEC (μg/L) 181 Maximum 1

- in

- 10 year 21

- day average value from surface water modeling. The estimated time to reach steady state was 93 days.

Water column EEC (μg/L) 178 Maximum 1

- in

- 10 year 60

- day average value surface water modeling. The estimated time to reach steady state was 93 days. Based on the NC cotton use scenario (0.45 lb a.i. x 2 (applications)+ 0.22 lb a.i. x 1 application @ 10

- d interval)



### Based on KABAM results, estimated concentrations of methoxyfenozide residues in the tissue s of organisms in the different trophic levels following application on cotton (NC) range from 23,180

to 46,798 mg/kg

- tissue ( Table 12 ). The measured bioconcentration potential of methoxyfenozide in bluegill sunfish viscera was 22.1 L/kg (4.42 mg/kg) , and is lower than BCF values estimated in KABAM modeling. The maximum BCF from KABAM was 263 L/Kg in the whole fish, suggesting that the mo del yields high

- end estimates of residues in fish and that fish may be able to

metabolize methoxyfenozide

.

### 27 Table 12

. Predicted concentrations of methoxyfenozide in aquatic organism tissues at different trophic levels ( μg/kg)

.

Use Scenario Phytoplankton Zooplankton Benthic

Invertebrates Filter

Feeders 1 Small

Fish Medium

Fish Large

Fish

NC Cotton 2 43,774 32,147 35,172 23,180 45,566 46,030 46,798

1 Filter feeders include clams, krill, sponges, whales, and many fish and may be vertebrates or invertebrates.

2 NC Application rate: 0.45 lb a.i. x 2 (applications)+ 0.22 lb a.i. x 1 application @ 10

- d interval



### Because a reliable metabolism rate constant cannot be generated to parameterize KABAM, the empirical BCF values for fish w ere used to estimate methoxyfenozide concentrations in aquatic organisms. The empirical bioconcentration factor (BCF) for methoxyfenozide is 263 L/kg for

whole fish. Maximum 1

- in

- 10

- year 60

- day average EECs for the scenarios explored for aquatic modeling ranged from 12.9

- 182 μ g a.i. /L. The estimated concentrations in aquatic organisms resulting from this range of EECs are used in combination the measured BCF to bracket the potential concentrations of methoxyfenozide in aquatic vertebrate tissues (at steady state). It

should be noted that tissue concentrations in aquatic vertebrates will likely be limited by toxicity

of methoxyfenozide to these organisms. For instance, the NOAEC for aquatic vertebrates exposed

to tribufos is 3. 1 μg a.i./L. At the LOAEC (6.3 μg a.i./L)

, delayed e mergence and development

were observed . Given that we expect a range of sensitivities in different aquatic invertebrates, some sensitive aquatic vertebrates would be expected to experience effects at the estimated concentrations while less sensitive speci es could carry residues in tissue without showing effects. Assuming EECs of 12.9

- 182 μg a.i./L and BCF value of 263 L/kg , methoxyfenozide concentrations in aquatic vertebrate tissues may range from 3.3 to 48 mg a.i./kg (diet) (BCF x

EEC = Concentration i n fish).

3.2.3.4 Exposure to Terrestrial Plants

Risk to terrestrial and semi

- aquatic plants was estimated using the TerrPlant model (version 1.2.2). The model generates EECs for plants residing near a use area that may be exposed via runoff and/or spray drift. The EECs are generated from one applicatio n at the maximum rate for a particular use, and using compound

- specific solubility information. Only a single application is considered, based upon the assumptions that for plants, toxic effects are likely to manifest shortly after an initial exposure, an d that subsequent exposures do not contribute to the response. Hence, the model estimates EECs based on application rate, solubility, and default assumptions regarding

drift. For an example model output of TerrPlant, see Appendix E

.

3.3 Ecological Effect s Characterization

The ecological effects characterization for methoxyfenozide is based upon registrant

- submitted toxicity data for the technical grade active ingredient ( TGAI ) and registered methoxyfenozide formulations. The ecotoxicity data available for methoxyfenozide at the time the docket opened

were discussed in a Preliminary Problem Formulation for Registration Review 15



### . M any aquatic and terrestrial organism toxicity studies have been submitted since the Preliminary Problem

15 US EPA, 2013.

### 28 Formulation was comple ted and are included in this assessment. The most sensitive endpoints used for risk assessment are summarized briefly in Sections 3.3.1 and 3.3.2

.

A search of the ECOTOX database in 201 4 yielded no new data from suitable studies with more

sensitive toxi city endpoints than those obtained from registrant

- submitted guideline studies

described below. Appendix C provides a full listing of the ecological effect data that have been submitted for methoxyfenozide.

3.3.1 Aquatic Effects Characterization

Based on the most sensitive toxicity endpoints, methoxyfenozide is classified as moderately toxic to estuarine/marine invertebrates and as very highly toxic to freshwater invertebrates on an acute exposure basis ( Table 1 3 ). With freshwater and estuarine/marine fish (and aquatic

- phase amphibians, for which freshwater fish serve as surrogates)

, the acute toxicity endpoint is non

definitive ( i.e., “>” value) and is close to the limit of solubility. This suggests that the potential acute toxicity of methoxyfenozide to these taxa is limited by the chemical’s solubility (3.3 mg/L

at 25 o 

### C).

The midge ( Chironomus riparius ), a freshwater benthic invertebrate, was the most sensitive species tested on a chronic exposure basis, and manifested delayed emergence and develo pment of the species (at the LOAEC of 0.0 063 mg a.i./L (mean measured pore water concentration) . O nly 45% of the midges emerged, and these developed more slow ly than controls

.

Toxicity data show adverse effects on survival in freshwater fish exposed to methoxyfenozide on a chronic exposure basis. Chronic toxicity data in fish indicate that freshwater f athead minnow

, Pimephales promelas

, ( NOAEC=0.53 mg a.i./L based on survival) are more sensitive to methoxyfenozide than the estuarine /marine s heepshead minnow, Cyprinodon variegatus

, ( NOAEC=1.5 mg a.i./L based on growth). Since n o acute toxicity data are available for midge

larvae

, an acute

- to

- chronic ratio ( ACR ) was used to calculate an acute freshwater invertebrate endpoint using acute and chr onic toxicity data from another aquatic invertebrate, i.e

., the

freshwater waterflea ( Daphnia magnia ) 16 

### . This results in an estimated EC 50 

### of 0 .0 6 mg a.i./L for the midge 17



### .

It is noteworthy however, that measured concentrations (5 % of nominal concentrations ) in the

sediment on D ay 28 ranged from 90 to 381% of the nominal concentration with an average of

276% of nominal. Thus

, exposure is difficult to quantify and larvae may not have been exposed to

the full nominal value over the course of the study.

The registr ant

- submitted data examining the effects of chronic exposure to methoxyfenozide on the development of African clawed frogs ( Xenopus laevis ) in response to uncertainties regarding

16 The most sensitive acute and chronic endpoints available for Daphnia are an EC 50 of 3.7 mg a.i./L (MRID

441444

- 11) and a NOAEC of 0.20 mg a.i./L (MRID 446177

- 14), respectively.

17 Acute

- to

- Chronic Ratio (ACR) was used to estimate the acute toxicity for the midge using the ratio of acute to chronic data points from studies with Daphnia and the chronic NOAEC from the midge lifecycle test. [(3.7 mg a.i./L)/(0.20 mg a.i./L) = (0.06 mg a.i./L)/(0.0031 mg a.i./L)]

### 29 potential impacts of the chemical on the hypothalamic

- pit uitary

- thyroid axis (HPT)

. Based on the lack of effects on developmental biomarkers or thyroid histology, methoxyfenozide did not appear to affect the development of Xenopus laevis up to 0.0747 mg a.i./L (the highest concentration used in the amphibian metamorphosis assay )

.

The freshwater g reen algae ( Pseudokirchneriella subcapitata ) was the most sensitive aquatic non

vascular plant tested, but the endpoint was non

- definitive, i.e ., the effect concentration for 50% mortality of the alga e exceeded the highest concentration tested (EC 50 

### >3.4 mg a.i./L), suggesting that the chemical’s solubility limit s its impacts on aquatic non

- vascular plants. Data on the effects of methoxyfenozide on aquatic vascular plants are not available. In compariso n, aquatic plant data

for tebufenozide , a compound in the same chemical family as methoxyfenozide, are available. Like methoxyfenozide, tebufenozide is also a dibenzoyl hydrazine which acts as invertebrate hormone analog (ecdysone agonists) ; b oth compounds are intended to induce precocious molting and subsequent death in target pests (specifically in Lepidoptera). Tebufenozide had no significant effect on vascular aquatic plant survival or growth in a seven

- day static

- renewal test with duckweed ( Lemna gibba ) or in a 96

- hour nonvascular aquatic plant toxicity test with green algae ( P

. subcapitata ).

For estuarine/marine invertebrates, acute data on E astern oysters ( Crassostrea virginica ) indicate

a 96

- hour EC 50 

### of 1.2 mg a.i./L (shell deposition study) which classifies methoxyfenozide as moderately toxic on an acute exposure basis . C hronic toxicity data for methoxyfenozide are available for an estuarine/marine crustacean, i.e

., the mysid shrimp ( Americamysis ba hia ). In this study

, reduced growth (length) occurred, with a NOAEC of 0.025 mg a.i./L.

The registrant also submitted data on red swamp crayfish ( Procambarus clarkia ) to address an

uncerta i n ty regarding whether other economically important aquatic organ isms that molt (such as

other crustaceans) may be sensitive to methoxyfenozide. Exposure of juvenile crayfish to methoxyfenozide for 32 days did not affect survival, growth (length or weight), total number of molts or number of molts per females in crayfis h at any of the test concentrations (EC 50 

### : > 0. 190

mg a.i./L; NOAEC: 0. 190 m g a.i./L; )

. The study is scientifically sound; however, it is classified as supplemental because it is a non

- guideline study. Table 1 3 contains a summary of ecological toxicity data for aquatic organisms with the greatest sensitivity to methoxyfenozide. Appendix C includes all of the reviewed ecological effects data relevant to this action.

Table 1 3 : Summary of the Most Sensitive Endpoints from Aquatic Toxicity Studies for

Meth oxyfenozide

Taxonomic

Group Study Type Test Species Toxicity Value (all units in terms

of measured active ingredient) Acute Toxicity

Classification Source (MRID) Study Classification

Freshwater

Fish 96

- Hour Acute Toxicity Rainbow trout Oncorhynchus mykiss LC 50 >4.2 mg a.i./L (No mortality at the

highest treatment

level tested) Moderately to Practically

Non

- Toxic 2 441444

- 10 Acceptable

### 30 Taxonomic

Group Study Type Test Species Toxicity Value (all units in terms

of measured active ingredient) Acute Toxicity

Classification Source (MRID) Study Classification

Full Life Cycle Toxicity Fathead minnow Pimephales promelas NOAEC=0.53 mg

a.i./L LOAEC=1.0 mg a.i./L (survival) N/A 446177

- 16 Acceptable

Freshwater

Invertebrates Estimate based on

Acute

- to

- Chronic

Ratio 1

Midge

Chironomus

riparius EC 50 = 0.06 1 mg a.i./L (mortality) Very highly

toxic N/A 1 N/A

Chronic Effects on

Midge Larvae (28

- d) NOAEC=0.0031 mg

a.i./L

LOAEC=0.0063 mg a.i./L

(Delayed emergence

and development) N/A 450328

- 01 Supplemental (non

- guideline)

Estuarine/

Marine Fish 96

- Hour Acute Toxicity Sheepshead

minnow

Cyprinodon variegatus 96

- hr LC 50 >2.8 mg

a.i./L Moderately to Practically

Non

- Toxic 441444

- 12 Acceptable

Early Life Stage Toxicity

(28

- d) NOAEC = 1.5 mg

a.i./L

LOAEC = 2.6 mg

a.i./L

(growth) N/A 446177

- 12 Acceptable

Estuarine/

Marine

Invertebrates 96

- Hour Shell Deposition Eastern oyster

Crassostrea

virginica 96

- hr EC 50 = 1.2 mg

a.i./L Moderately

Toxic 441444

- 13 Acceptable

Invertebrate Life Cycle Toxicity (28

- d) Mysid

Americamysis bahia ( formerly

Mysidopsis

bahia) NOAEC = 0.025 mg

a.i./L LOAEC = 0.051 mg

a.i./L (Reduced growth/length) N/A 446177

- 15 Acceptable

Non

Vascular Aquatic

Plants 5

- Day Toxicity

Test Freshwater alga

Pseudokirchnerie

lla subcapitata

( formerly

Selenastrum capricornutum) EC 50 >3.4 mg a.i./L

NOAEC= 3.4 mg

a.i./L

No effects at the highest treatment

level tested N/A 446177

- 18 Acceptable

1 Acute

- to

- Chronic Ratio (ACR) was used to estimate the acute toxicity for the midge using the ratio of acute to chronic data points fro m studies with Daphnia magna and the chronic NOAEC from the midge lifecycle test. [(3.7 mg a.i./L)/(0.20 mg a.i./L) = (0.06 mg a.i./L)/(0.0031 mg a.i./L)]

2 A definitive endpoint was not achieved at or near the solubility limit of methoxyfenozide.

### 31 3.3.2 Terrestrial Effects Characterization

Methoxyfenozide is classified as practically non

- toxic to birds (as well as to reptiles and terrestrial

phase amphibians, for which birds serve as surrogates) on both an acute oral and subacute dietary exposure basis; the compound is prac tically non

- toxic to mammals on an acute oral exposure basis. In a reproductive toxicity study in bobwhite quail ( Colinus virginianus ), methoxyfenozide was associated with a statistically significant d ecrease in eggshell thi ckness compared to untreated

controls (6 % decrease at 780 mg/kg diet) . Across the dietary treatment levels of methoxyfenozide tested, declines in eggshell thickness were accompanied with increases in the number of eggs cracked, although the increase in the num ber of eggs cracked was not statistically significant. The

measurement endpoint of eggshell thinning i s used to calculate chronic risk to birds (NOAEC=520 mg/kg

- diet ; LOAEC = 780 mg/kg

- diet) ). No other effects were observed in chronic toxicity studies

with birds

.

In a 2

- generation (1 litter/generation) reproduction study in rats, treatment

- related organ and histological effects were observed only at 20,000 ppm , the highest dose tested for the parental generation . At this dose, increased liver weights wer e observed in males and females of both generations and midzonal to periportal hepatocellular hypertrophy was observed in the livers of all males and females of both generations. There were no treatment

- related effects on reproductive parameters for adult (parent) animals , nor were effects on growth or survival noted

. For ecological risk assessment purposes, the chronic NOAEL from this study is 20,000 ppm.

Methoxyfenozide is classified as “practically non

- toxic ” to adult honey bee s ( Apis mellifera ) on both an acute oral and contact exposure basis

. T he European corn borer ( Ostrinia nubilalis )

, a lepidopteran target pest

, is more sensitive ( LC 50 

### =0.009 mg/kg

- diet 18 

### )

. Although methoxyfenozide is intended to target lepidopteran s (such as armyworm, cutworms, etc .) , there is uncertainty regarding the extent to which other orders of insects and taxa dependent on ecdysone may be affected. Because of methoxyfenozide’s mode of action, immature insects may be more sensitive to methoxyf enozide than are adult insects.

Based on EPA risk assessment guidance on bees 19 

### , t wo higher

- tiered semi

- field studies on honey bees are available for methoxyfenozide. The semi

- field honey bee brood study (MRID 45065501) involved feeding adult bees a suc rose syrup containing 101 mg methoxyfenozide/L for 3 weeks

. In the longer

- term colony overwintering study (MRID 48962201 ) adult bees were fed sucrose

syrup containing methoxyfenozide at concentrations ranging from 6.25

- 100 mg methoxyfenozide/L for 4 days (observation of the bees continued for 300 days) . Overall, the submitted toxicity data for honey bee colonies suggest that the compound does not adversely affect colony brood development and/or overwintering survival, although confounding issues were noted

in the field

- based studies with whole colonies. Further, t here is uncertainty regarding the extent

to which the treatment concentrations in the two semi

- field studies are representative of those resulting from the use of methoxyfenozide at the maximum a pplication rate.

18 Trisyono and Chippendale, 1997.

19 USEPA et al. 2014. Guidance for Assessing Pesticide Risks to Bees. Available at: http://www2.epa.gov/pollinator

- protection/pollinator

- risk

- assessment

- guidance Last accessed 09/16/15.

### 32 New data on the acute toxicity of methoxyfenozide for larval honey bees were recently submitted to the agency under FIFRA Section 6(a)(2) 20 

### . The 7

- day laboratory

- based acute (single dose) toxicity study with larval honey bees was conduct ed according to OECD 237 21 

### . The design consisted of a negative control, five concentrations of methoxyfenozide (ranging from 0.119 μg a.i./bee to 40 μg a.i./bee) and a reference substance (dimethoate, PC code 035001). The 7

- day study resulted in a 72

- hour L D 50 

### of 3.69 μg/larvae

, although the dose

- response curve was initially erratic and there were concerns regarding contaminants (chloramphenicol and sulfonamide antibiotics) in the royal jelly used to feed developing larvae. In general, mean control (negative and solvent) met the OECD study validation criterion of <15% mortality and the study is classified as supplemental.

It is unclear why effects were manifest ed in the laboratory study but not in semi

- field, colony

- level

studies. In a real

- world setting , as colony

- level stud ies are designed to reflect , the larval diet during early stages of development consist s largely of royal jelly, a secretion produced by the hypopharyngeal glands of the nurse bees . It is possible that the concentration of methoxyfenozide

in the royal jelly produced in the hive , where adult bees were feed sucrose syrup containing methoxyfenozide, was lower in concentration than what was f ed directly to the larvae in the laboratory

- based study . Also, t he laboratory

- based study involve d a single exposure to

met hoxyfenozide while the duration of exposure in the colony

- level studies was longer . T here

were confounding issues in both types of studies . Additional laboratory

- based toxicity data would be useful to resolve whether the toxicity expressed after a single dose is reflected in a longer

- term
repeat

- dose study. The 21

- day larval toxicity test developed by the Organization for Economic Cooperation and Development would provide a means of addressing this uncertainty as it is a repeat dose study that extends thr ough adult emergence.

No data are available to assess the effects of methoxyfenozide on terrestrial plants. However, terrestrial plant toxicity data are available for tebufenozide, another dibenzoyl hydrazine ecdysone agonist which acts as an ecdysone agonist

. The tebufenozide tier 1 vegetative vigor and seedling

emergence studies can inform our understanding of the potential toxicity of methoxyfenozide to terrestrial plants.

Tebufenozide result ed in reduced growth (dry weight) in a terrestrial dicot yledonous (dicot) specie s (radish) exposed at 0.97 lb a.i./acre ( dry weight reduced by 14%) and 1.97 lbs a.i./A (7%) in a vegetative vigor study; the effect was statistically significant (p<0.05) at the lowest rate tested and a NOAEL was not established (MR ID 48533002). Similarly, a NOAEL was not established for dicot plants in the seedling emergence test where cabbage emergence was significantly reduced (p<0.05) by 14% compared to the negative control at the lowest t reatment rate of 0.98 lbs a.i./acre (mea sured) (MRID 48533001). No other statistically significant effects were observed either study. An effect greater than 25% was not observed in either test ; therefore the EC 25 

### is greater than the highest rate tested

.

20 http://www.epa.gov/pesticides/fifra6a2/

21 http://www.oecd

- ilibrar y.org/environment/test

- no

- 237

- honey

- bee

- apis

- mellifera

- larval

- toxicity

- test

- single

exposure_9789264203723

- en

### 33 G iven 1) the mode of action of the compound (insect growth regulator ), 2) the available information on a similar compound (tebufenozide), and 3) the lack of reported plant incidents for methoxyfenozide (see Section 3.3.3 below)

, the likelihood of adverse effects on terrestrial plants

from m ethoxyfenozide is expected to be low

.

Table 14 contains a summary of ecological toxicity data for terrestrial organisms with the greatest sensitivity to methoxyfenozide

.

Table 1 4 : Summary of the Most Sensitive Endpoints from Terrestrial Toxicity Studies for Methoxyfenozide

Taxonomic

Group Study Type Test Species Toxicity Value Acute Toxicity

Classification Source (MRID) Study Classification

Birds Acute Oral Toxicity Northern bobwhite quail

Colinus virginianus LD 50 >2,250 mg a.i./kg

- bw

No effects at highest

treatment level tested Practically

Non

- Toxic 441444 06 Acceptable

Subacute Dietary Toxicity Northern bobwhite quail

Colinus virginianus LC 50 >5,870 mg a.i./kg

- diet

No effects at highest

treatment level tested Practically

Non

- Toxic 44144407 Acceptable

Avian Reproductive Toxicity Northern bobwhite quail

Colinus virginianus NOAEC= 52 0 mg a.i./kg

- diet

(Reduction in eggshell thickness) N/A 44617711 Acceptable

Mammals Acute oral Toxicity Rat

Rattus norvegicus LD 50 >5,000 mg a.i./kg

- bw Practically

Non

- Toxic,

Acute Toxicity Category 4 44144415 Acceptable

Two

- Generation Toxicity Rat

Rattus norvegicus N OAEC = 20 ,000

ppm diet

LOAEC >20,000 ppm diet N/A 44617727 Acceptable

Terrestrial

Invertebrates Acute Contact Toxicity (adults)

Honey bee

Apis mellifera LD 50 >100 μg

a.i. /bee Practically

Non

- Toxic 44144429 Acceptable

Acute Oral Toxicity (adults) 72

- hour LC 50 >100 μg a.i./bee Practically

Non

- Toxic 44617717 Supplemental (non

- guideline)

Acute Larval Toxicity (7

- day) 72

- hour LD 50 = 3.69 μg a.i./bee Moderately

Toxic 49672801 Supplemental (non

- guideline)

### 34 Taxonomic

Group Study Type Test Species Toxicity Value Acute Toxicity

Classification Source (MRID) Study Classification

Chronic Larval Toxicity (21

- day) NOAEL=101 mg

a.i./L N/A 45065501 Supplemental

1 Birds represent surrogates for terrestrial

- phase amphibians and reptiles.



### 3.3.3 Ecological Incidents

The ecological incident information system (EIIS) is a database maintained by the O ffice of

P esticide P rograms; the database contains ecological incidents that have been reported to the Agency. When available, EIIS includes date and location of an incident, type and magnitude of effects observed in various species, use(s) of pesticides known or suspected of contributing to the

incident , and results of any chemical residue analysis or other analyses conducted during incident investigation. EIIS incidents are categorized according to the certainty that the incident resulted from pesticide exposure. The Avian Incident Monitoring System ( AIMS) 22 

### is a database administered by the American Bird Conservancy that contains publicly available data on reported avian incidents involving pesticides. Many of the incidents listed in this database are also in the

EIIS. Because of uncertainties regard ing the extent to which incidents are reported to EPA, the absence of incident reports cannot be construed as the absence of incidents.

EIIS contains six incident reports for methoxyfenozide. All six are reported bee kills in which methoxyfenozide was me ntioned. Five reported incidents took place in California, and one in New

York State

. The legality of the uses that led to these reports is not known, nor is it known whether misuse of methoxyfenozide was a factor in these reported incidents. Importantly , f or all of these incidents, more than one pesticide was named along with methoxyfenozide , meaning that the applicators likely tank

- mixed methoxyfenozide with other chemicals and applied the mix as a

spray . Since methoxyfenozide alone does not appear to be toxic to adult honey bees on an acute contact or oral exposure basis and since the se bee kill incidents involved the loss of adult bees , it

is un certain whether methoxyfenozide was the cause of the se losses

. EPA does not have toxicity

data n or does it conduct risk assessments for tank mixes of different chemicals or combinations of active ing redients. It is unknown whether methoxyfenozide ’s potential toxicity to bees is enhanced

or otherwise affected by other chemicals t hat may be tank mixed with it or sprayed concurrently

.

In the Office of Pesticide Programs’ Aggregate Incident Reports, there were no incidents attributed to methoxyfenozide. AIMS was also searched on February 20, 2015 and revealed no incidents to birds associated with methoxyfenozide.

Table 1 5 : Summary of Methoxyfenozide Inciden t s (March, 2015)

Chemical Name (Product Name) Crop Incident Data System

Number Date Certainty Location Affected Taxa (Magnitude of

Incident) Application

Method

22 American Bird Conservancy. 2015. Avian Incident Monitoring System. http://www.abcbirds.org/abcprograms/policy/toxins/aims/aims/login.cfm

### 35 Methoxyfenozide

(Intrepid ® 2F) Pistachios I023107

- 019 July 2011 Unlikely Kings Co,

California Honey bees (92 colonies) Ground

Almonds I024029

- 001 February

2012 Possible Seneca Co,

California Honey bees (464 colonies) Unknown

Unknown I024270

- 001 May 2012 Unlikely Seneca Co,

New York Honey bees (48 colonies) Drift from seed planting

Almonds I025162

- 001 May 2013 Unlikely Madera Co,

California Honey bees ( 12,000 colonies ) Unknown

Almonds I026240

- 001 February

2014 Possible Merced Co,

California Honey bees (7,800 colonies) Airblast/ Ground

Almonds I026517

- 001 March 2014 Possible Merced Co,

California Honey bees (2000 colonies) Unknown



### 4.0 Risk Characterization

4.1 Risk Estimation

This screening

- level ass essment of the labeled uses of methoxyfenozide relies on the deterministic RQ method to provide a metric of potential risks. The RQ provides a comparison of exposure estimates to toxicity endpoints ( i.e. , the estimated exposure concentrations are divided by acute and chronic toxicity values , respectively ). The resulting unitles s RQ values are compared to the Agency’s LOCs. The LOCs , when exceeded, are used by the Agency to indicate when the use of a pesticide, as directed by the label, has the potential to cause adverse effects to non

- target organisms. For endangered species, LOC exce e dances require an additional in

- depth evaluation of the potential co

- occurrence of listed species and areas in which new use crops are grown to characterize risks. In all cases, RQs that exceed the risk to non

- listed species LOC s also exceed

the listed species LOC s (See Table 2 above)

.

4.1.1 Aquatic Organisms

In the acute freshwater fish, acute estuarine/marine fish, and non

- vascular aquatic plant toxicity studies submitted, there were no mortality or sub

- lethal effects at the highest treatment levels tested ( i.e ., LC 50, 

### endpoints are ‘greater than’ values); therefore, these endpoints are not used to calculate risk quotient ( RQ ) values. H owever, the information in these studies was used to help characterize potential risk in the Risk De scription section ( 4.2 ) of this assessment

.

4.1.1.1 Aquatic Invertebrates

Acute and chronic risk to aquatic invertebrates were assessed by comparing exposure in surface water following methoxyfenozide use to the most sensitive toxicity endpoints identified in aquatic invertebrate studies. Acute RQs for freshwater invertebrates were calculated using the ACR

estimated EC 50 

### of 0.06 mg a.i./L (57 μg a.i./L) for the C

. riparius , and chronic RQs were calculated using the empirical NOA EC of 0.0031 mg a.i./L (3.1 μg a.i./L) (pore water concentration) for the midge. Acute RQs for estuarine/marine invertebrates were calculated using the EC 50 

### of 1.2 mg

### 36 a.i./L (1200 μg a.i./L) for the Eastern oyster . C hronic RQs were calculated using the NOA EC of 0.025 mg a.i./L (25 μg a.i./L) for the mysid.

For all of the registered uses of methoxyfenozide, R Qs for freshwater invertebrates exceed the Agency’s acute risk levels of concern ( LOCs ) for listed (LOC=0.05) and non

- listed (LOC=0.5) species . Chronic RQs also exceeded the LOC for freshwater invertebrates (LOC=1) for all of the registered uses

. For estuarine/marine invertebrates, RQs for most of the registered use sites exceed the Agency’s acute risk LOC s for listed and non

- listed species exc ept for uses on grass forage and

bushberries. However, for all registered uses, RQs exceed the chronic risk LOC for

estuarine/marine invertebrates. Acute and chronic RQs for aquatic invertebrates are presented

below in Table 1 6

.

Table 1 6 : Acute and Chronic RQ Values for Freshwater and Estuarin e/Marine Invertebrates for the Registered Uses of Methoxyfenozide

Use Site ( Scenario ) Exposure Type EEC ( μg a.i./L) Freshwater Invertebrate RQ 1 Estuarine/Marine Invertebrate RQ 2

Acute Chronic Acute Chronic

Citrus (FL Citrus) Acute 104 (peak) 1.82 a,b 0.09 a

Chronic 103 (21

- day) 33.2 c 4.12 c

Cotton (NC Cotton) Acute 185 (peak) 3.25 a,b 0.15 a

Chronic 183 (21

- day) 59.0 c 7.32 c Fruiting Vegetables (FL Pepper) Acute 135 (peak) 2.37 a,b 0.11 a

Chronic 133 (21

- day) 42.9 c 5.32 c

Globe Artichokes (CA Lettuce) Acute 144 (peak) 2.53 a,b 0.12 a

Chronic 143 (21

- day) 46.1 c 5.72 c Grass Forage, Fodder Hay (OR Grass Seed) Acute 37.4 (peak) 0.66 a,b 0.03

Chronic 37.1 (21

- day) 12.0 c 1.48 c

Bushberries (OR Berries) Acute 52.7 (peak) 0.92 a,b 0.04

Chronic 52.2 (21

- day) 16.8 c 2.09 c

Peanuts (NC Peanuts) Acute 5 4.5 (peak) 0.9 6 a,b 0.05 a

Chronic 54.0 (21

- day) 17.4 c 2.1 6 c

Corn (MS Corn) Acute 1 44 (peak) 2. 52 a,b 0.1 2 a

Chronic 143 (21

- day) 4 6.1 c 5. 7 2 c Grapes (NY Grapes) Acute 1 4 1 (peak) 2.47 a,b 0.1 2 a

Chronic 140 (21

- day) 45 .2 c 5. 6 c

Tree Nuts (CA Almonds) Acute 101 (peak) 1.77 a,b 0.0 8 a

Chronic 100 (21

- day) 32.3 c 4 .00 c

1 Based on an ACR

- calculated EC 50 of 0.06 mg a.i./L (57 μg a.i./L) (midge, Chironomus riparus ) and a NOAEC of 0.0031 mg a.i./L (3.1μg a.i./L ) (midge, Chironomus riparus ).

2 Based on an EC 50 of 1.2 mg a.i./L (1200 μg a.i./L) (Eastern oyster, Crassostrea virgi nica ) and a NOAEC of 0.025 mg a.i./L (25 μg a.i./L) (mysid, Americamysis

bahia ).

a exceeds acute risk to listed species LOC ( i.e ., RQ≥0.05);

b exceeds acute risk to non

- listed species LOC ( i.e , RQ≥0.5);

c exceeds chronic risk LOC (RQ≥1)

.



### 4.1.1.2 Fresh water and Estuarine/Marine Fish

A cute risk to either freshwater fish (or aquatic

- phase amphibians) or estuarine/marine fish from methoxyfenozide was not assessed since the 96

- hr LC 50 

### value exceeded the highest concentration tested and no mortality was observed at the highest concentration. Chronic RQs for freshwater

### 37 fish were calculated using the most sensitive NOAEC of 530 μg a.i./L based on reduced survival

for the f athead m innow

, and chronic RQs for marine/estuarine fish were calculated using the most

sensitive NOAEC of 1500 μg a.i./L based on reduced growth for the sheepshead minnow. C hronic RQ value s for freshwater and marine/estuarine fish do not exceed the chronic risk LOC (RQ≥ 1.0)

for any of the assessed uses ( Tabl e 1 7 ).

Table 1 7 . Chronic RQ Values for Marine/Estuarine and Freshwater Fish from

the Registered Use of Methoxyfenozide

Use Site (Scenario) Exposure Type EEC ( μg a.i./L) Freshwater

Fish Chronic RQ 1 Marine/Estuarine

Fish Chronic RQ 2

Citrus (FL Citrus) Chronic 103 (21

- day) 0.19 0.69

Cotton (NC Cotton) Chronic 183 (21

- day) 0.35 0.12

Fruiting Vegetables (FL Pepper) Chronic 133 (21

- day) 0.25 0.09

Globe Artichokes (CA Lettuce) Chronic 143 (21

- day) 0.27 0.10

Grass Forage, Fodder Hay (OR Grass Seed) Chronic 37.1 (21

- day) 0.07 0.02

Bushberries (OR Berries) Chronic 52.2 (21

- day) 0.10 0.03

Peanuts (NC Peanuts) Chronic 54.0 (21

- day) 0.10 0.04

Corn (MS Corn) Chronic 143 (21

- day) 0.27 0.10

Grapes (NY Grapes) Chronic 140 (21

- day) 0.26 0.09

Tree Nuts (CA Almonds) Chronic 100 (21

- day) 0.19 0.07

1 Based on a NOAEC of 530 μg a.i./L (fathead minnow, Pimephalas promelus ).

2 Based on a NOAEC of 1500 μg a.i./L (sheepshead minnow, Cyprinodon variegatus ).



### 4.1.1.3 Aquatic Plants

As stated earlier, t he freshwater green algae ( P

. subcapitata ) was the most sensitive aquatic non

vascular plant tested, but the endpoint in the toxicity study was non

- definitive, i.e ., the effect concentration for 50% mortality of the algae exceeded the highest concentration tested (EC 50 

### >3.4 mg a.i./L), suggesting that the chemical’s solubility (3.3 mg/L) may limit its impacts on aquatic

non

- vascular plants. As noted earlier, d ata on the effects of methoxyfenozide on aquatic vascul ar plants are not available. However, aquatic plant data for tebufenozide, a n IGR in the same chemical class and mode of action

, demonstrated no significant effect on vascular aquatic plant survival or growth in a seven

- day static

- renewal test with duckwe ed ( Lemna gibba ) or in a 96

- hour nonvascular aquatic plant toxicity test with green algae ( P

. subcapitata ). Also, t ebufenozide degradates had no effect on the green algae at concentrations up to the limits of water solubility of

tebufenozide (0.83 mg/L)

. Therefore, aquatic plant RQs for methoxyfenozide were not calculated.

### 38 Based on aquatic plant toxicity data for methoxyfenozide and tebufenozide , the likelihood of adverse effects on aquatic plants from exposure to methoxyfenozide is considered low

.

4. 1.2 Terrestrial Organisms

4.1.2.1 Risk to Birds

In the avian acute toxicity studies submitted, there were no mortality or sub

- lethal effects at the highest treatment levels tested ( i.e ., the acute oral LD 50 

### and sub

- acute dietary LC 50 

### values are ‘greater than (>)’ values); therefore, acute RQs for birds (and for terrestrial

- phase amphibians and reptiles for which birds serve as surrogates) were not calculated. H owever, the information in these

studies was used to help characterize risk in the ‘Risk Description’ section of this assessment.

Exposure estimates for birds were calculated using upper

- bound Kenaga values calculated using

T

- Rex version 1.5.2. For chronic risk to birds

, the highest (most conservative) exposure estimates (EECs) generated by T

- REX were dietary

- based EECs (See Section 3.2.3.1 ) . I ngestion of contaminated prey was estimated using KABAM based on BCF values, and 1

- in

- 10 year 60

- day

water

- column concentrations were estimated using the SWCC. D ietary

- based EECs were compared to the most sensitive chronic toxicity endpoints to calculate chronic RQs. The highest dietary

- based EECs for the registered uses resulted from uses on corn, tree nuts and cotton (see

Table 1 0 )

. These three uses were chosen to represent the most conservative estimate s of chronic risk to birds from all of the registered uses of methoxyfenozide. Chronic RQs for use on corn, tree

nuts and cotton are presented below in Table 18

. Based on the example of these most conservative

e stimates, we conclude that chronic avian risks for all use patterns are below the Agency’s level

of concern

.

Table 18 . Dietary

- based Upper

- Bound Avian Chronic EEC and RQ Values for Methoxyfenozide

Application

Method Dietary

- Based EECs and RQs 1

Short Grass Tall Grass Broadleaf Plants/

Small Insects Fruits/Pods/

Seeds/ Large Insects

EEC 2 RQ EEC RQ EEC RQ EEC RQ

Use Site/Crop Group (Max. Single Application Rate)

Corn (0.25 lb a.i./A)

Ground/Aerial 220 0.42 101 0.19 124 0.24 13.8 0.03

Tree Nuts (0.38 lb a.i./A )

Ground/Aerial 278 0.53 127 0.24 156 0.30 17.4 0.03

Cotton (0.4 lb a.i./acre)

Ground/Aerial 292 0.56 134 0.26 164 0.32 18.3 0.04

1 Based on a NOAEC of 520 mg a.i./kg

- diet (Northern bobwhite quail, Colinus virginianus ).

2 From T

- REX, Version 1.5.2. See Appendix D for an example T

- REX printout

.

### 39 4.1.2.2 Risk to Mammals

In the available mammalian acute toxicity studies, there were no mortality or sublethal effects

observed at the highest treatment levels tested ( i.e ., the acute oral LD 50 

### is a ‘greater than (>)’ value); therefore, acute RQs were not calculated for mammals . However, information from the se studies

was used to characterize risk in the Risk Description s ection of this assessment.

In mammals, chronic exposure t o rats resulted in no treatment

- related effects on reproductive parameters for adult (parent) animals, nor were effects on growth or survival noted. For ecological risk assessment purposes, the chronic NOAEL from this study is 20,000 ppm.

Exposure esti mates for mammals were calculated using upper

- bound Kenaga values calculated using T

- Rex version 1.5.2. For chronic risk to mammals

, the highest (most conservative) exposure estimates (EECs) generated by T

- REX were dietary

- based EECs (See Section 3.2.3.1 ) . I ngestion of contaminated prey was estimated using KABAM based on BCF values, and 1

- in

- 10 year 60

- day water

- column concentrations were estimated using the SWCC . As a conservative measure, dietary

- based EECs were compared to the most sensitive chronic tox icity endpoints to calculate chronic RQs. The highest dietary

- based EECs resulted from uses on corn, tree nuts and cotton (see

Table 10 ). These three uses were chosen to represent the most conservative estimate s of chronic

risk to mammals from all of the r egistered uses of methoxyfenozide. Chronic mammalian RQs are presented below in Table 1 9 . Based on the example of these most conservative estimates, we conclude that chronic mammalian risks for all use patterns are below the Agency’s level of

concern.

Table 1 9 . Dietary

- based Upper

- Bound Mammalian Chronic EEC and RQ Values for Methoxyfenozide

Application

Method Dietary

- Based EECs and RQs 1

Short Grass Tall Grass Broadleaf Plants/

Small Insects Fruits/Pods/

Seeds/ Large Insects

EEC 2 RQ EEC RQ EEC RQ EEC RQ

Use Site/Crop Group (Max. Single Application Rate)

Corn (0.25 lb a.i./A)

Ground/Aerial 220.02 < 0.01 100.84 < 0.01 123.76 < 0.01 13.75 <0.01

Tree Nuts (0.38 lb a.i./A )

Ground/Aerial 277.73 < 0.01 127.29 < 0.01 156.23 < 0.01 17.36 <0.01

Cotton (0.4 lb a.i./acre)

Ground/Aerial 292.35 < 0.01 133.99 < 0.01 164.45 < 0.01 18.27 <0.01

1 Ba sed on a NOAEL of 20, 000 mg a.i./kg

- diet ( rat ).

2 From T

- REX, Version 1.5.2. See Appendix D for an example T

- REX printout

.



### Insufficient data are available to calculate a reliable metabolism rate constant to parameterize KABAM; therefore, the empirical BCF values for fish were used to estimate methoxyfenozide concentrations in aquatic organisms. The empirical BCF value for methoxyfenozide i s 263 L/kg

### 40 in whole fish and was measured for the bluegill sunfish. Maximum 1

- in

- 10

- year 60

- day average EECs for the scenarios explored for aquatic modeling ranged from 12.9 to 182 μg a.i./L. The estimated concentrations in aquatic organisms resulting from this range of EECs are used with the BCFs to bracket the potential concentrations of methoxyfenozide in aquatic vertebrate tissues (at steady state) in areas vulnerable to runoff. It should be noted that tissue concentrations in aquatic

vertebrates will likely be limited by the toxicity of methoxyfenozide on these organisms. For instance, the NOAEC for aquatic vertebrates exposed to methoxyfenozide is 3.1 μg a.i./L. At this concentration, delayed emergence and development were observed. Given that we exp ect a range of sensitivity in different aquatic invertebrates, some sensitive aquatic vertebrates would be expected to have effects at the estimated concentrations while less sensitive species could carry residues in tissue without showing effects. Assum ing EECs of 12.9 to 182 μg a.i./L and a BCF

value of 263 L/kg for whole fish, methoxyfenozide concentrations in aquatic vertebrate tissues

may range from 3.3 to 48 mg a.i./kg (diet ; BCF x EEC = concentration in fish). The highest of

t hese concentrations i s lower than the chronic dietary endpoints for mammals and birds. The chronic RQ for birds is 0.09 and for mammals is <0.01 indicating that exposure for birds and mammals consuming fish contaminated with methoxyfenozide is not likely to result in a risk

c oncern ( Table 20 )

.

Table 20 . RQ Values for Birds and Mammals Consuming Fis h

Use

Scenario Water

- Column

60

- day average EEC (μg/L) BCF (L/kg) Methoxyfenozide

conc entration in

fish ( m g/kg) Chronic RQ

Birds

NOAEC= 520 mg/kg

- diet Mammals

NOAEC= 20,000 mg/kg

- diet

Cotton 1 178 236 46.8 0.09 <0.01

1 NC cotton; 0.45 x 2 (applic ations ) + 0.22 x 1 applic ation . @ 10

- d interval



### 4.1.2.2 Terrestrial Plants

As noted earlier, no data are available to assess the effects of methoxyfenozide on terrestrial plants. However, terrestrial plant toxicity data (tier 1 vegetative vigor and seedling emergence studies)

are available for tebufenozide , a n insect growth regulator in the same class as methoxyfenozide

. By making the conservative assumption that the non

- de finitive values ( i.e.

, EC 25 

### >1.94 lbs a.i./A

and NOAEC <0.98 lbs a.i./A) from the seedling emergence and vegetative vigor studies for tebufenozide are definitive ( i.e

., assuming E C 25 

### =1.94 lb a.i./acre) and assuming a single application at the maximum label rate for the cotton use site (the highest single application rate) resulted in RQs that are below the LOC for risk to terrestrial plants (LOC=1.0).

4 .1.2.3

. Terrestrial Invertebrates

As noted previously, m ethoxyfenozide is classified as ‘practically non

- toxic ’ to adult honey bee s both on an acute oral and contact exposure basis but has been shown to be toxic to target lepidopteran pest species such as the European corn borer (a common pest of corn) on an acute dietary exposure basis (Trisyono and Chippendale

, 1997 )

. L epidopterans include more than 11,200 species in North America including the monarch butterfly ( Danaus plexippus ) for which

### 41 certain sub populations are in decline

, 23 

### and the listed Karner blue butterfly ( Lycaeides melissa

samuelis ) 24



### . There is uncertainty surrounding the extent of exposure of non

- target, beneficial lepidopterans to methoxyfenozide ( e.g., t iming of applications relative to presence of the lepidopterans, and location of applications relative to habitat or areas where lepidopterans feed

.

In 2006, EFED completed an interim endangered species risk assessment for the Karner Blue Butterfly ( Lycaeides melissa samueli s ) for the use of methoxyfenozide on cranberries in

Wisconsin 25 

### . An endangered species protection bulletin has been developed for the use of methoxyfenozide in areas where use of methoxyfenozide may overlap with habitat of the Karner Blue Butterfly (See: http://www.epa.gov/oppfead1/endanger/bulletins.htm ).

As stated earlier in this assessment

, adult honey bees do not appear to be sensitive to methoxyfenozide on an acute oral or contact expo sure basis. Therefore, RQs for adult honey bees

were not calculated.

Screening

- level RQ values were estimated for larval honey bees using the results of the recently

submitted acute toxicity data (MRID 49672801 ) and EECs for pollen and nectar based on

conservative models discussed in the Guidance for Assessing Pesticide Risks to Bees (US EPA, 2014)

. The food consumption rate of 0.124 g/day for 5

- day old larval honey bees was taken from

the Guidance ; 5

- day old larvae consume the more food than larvae of any other age . Based on the

7

- day larval toxicity data (LD 50 

### = 3.69 μg/bee), the scre ening

- level RQs for larval honey bees range

from 0. 03 to 1.4 ( Table 21 ) for the maximum application rate for almonds as well as typical application rate. At the m aximu m application rate, the RQ ( 1.4 ) exceeds the acute risk LOC of

0.04. RQ values were further refined using measured r esidue values discussed in Section 3.2.3.2

, and the resulting RQ is 0.32 , which is below the acute risk LOC

.

Table 21

. Larval Honey Bee Exposure ( EEC s) a nd RQ Values for Almonds Treated with Methoxyfenozide

Application Method (Rate)

(lb a.i./Acre) Pollen EEC (mg a.i./kg

pollen) Nectar

EEC (mg a.i./kg

nectar) Larvae Consumption

Rate (g/day) 5 LD 50 (μg a.i./bee) 3 Pollen RQ 4 Nectar RQ 4

RQs using Default Exposure Estimates 1

Ground (0.19 lb a.i./Acre) 20.9 1 N/A 0.124 3.69 0.70 N/A

Ground (0.38 lb a.i./Acre) 41.8 1 N/A 0.124 3.69 1.40 N/A

RQs using Refined Exposure Estimates

23 From US FWS (http://www.fws.gov/savethemonarch/): North American monarch butterflies are in trouble. Threats, including loss of milkweed habitat needed to lay their eggs and for their caterpillars to eat, are having a devastating impact on their populations and the migration phenomenon.

24 North Carolina State University Entomology Resource Library website. Accessed 7/9/15. Available at: http://www.cals.ncsu.edu/course/ent425 /library/compendium/lepidoptera.html

25 US EPA, 2006.

### 42 Ground (0.19 lb a.i./Acre) 9.42 2 0.794 6 0.124 3.69 0.32 0.03

1. Default EEC s calculated using Guidance for Assessing Pesticide Risk to Bees (US EPA, 2014) (=AR lb a.i./A*110 μg a.i./day).

2. Peak corbicular pollen residue value measured in the almond residue study with methoxyfenozide (MRID 48962202)

3. LD 50 from the acute (7

- day) larval honey bee toxicity study (MRID 49672801 ).

4. RQ = [ EEC (ppm)*Consumption rate (g/day) /LD 50 (μg a.i./bee)]

. 5. Consumption rates f rom Guidance for Assessing Pesticide Risk to Bees (US EPA, 2014)

. 6. Peak nectar residue value collected from honey bees’ stomachs measured in the almond residue study with methoxyfenozide (MRID 48962202)

.



### 4.2. Risk Description

Methoxyfenozide is characterized as persistent and moderately mobile and is expect ed to move into surface water through runoff an d spray drift following application. The widespread and prevalent use of methoxyfenozide ; its physio

- chemical characteristics and eco

- toxicity profile ; and

evidence of residues of the chemical in various environmental matrices ( e.g. , soil, pollen ) suggest
that non

- target lepidopterans and aquatic invertebrates can be exposed to the insecticide

. The results of this screening

- level risk assessment indicate that the registered uses of methoxyfenozide

ha ve the potential for direct adverse effects on listed and non

- listed freshwater invertebrates. T he RQs for freshwater invertebrates exceed the Agency’s LOCs for acute risk to listed and non

- listed species and LOCs for chronic risk s to listed and non

- listed species for all of the registered uses of methoxyfenozide

. RQ values for estuarine/marine invertebrates exceed the acute risk to listed species LOC for all but two of the uses evaluated and exceed the chronic risk LOC for all of the

uses evaluated

. The RQs for terrestrial invertebrates also exce ed the Agency’s LOCs for acute risk (0.4) for the registered use on almonds

. These results are based on EECs derived for maximum

lab eled rates for spray applications of methoxyfenozide

.

The likelihood of direct adverse effects to birds (terrestrial

- phase amphibians and reptiles)

, mammals, fish (aquatic

- phase amphibians) , terrestrial and aquatic plants

, and estuarine/marine invertebrates from exposure to methoxyfenozide as a result of the registered uses is expected to be low. However, the extent to which other taxa that may depend on freshwater aquatic invertebrate species may be indirectly affected is uncertain.

4.2.1 Risk to Aquatic Organisms

Methoxyfenozide is characterized as moderately toxic to freshwater fish, estuarine/marine

invertebrates

, and estuarine/marine fish

, and highly toxic to freshwater invertebrates on an acute exposure basis. Acute toxicity risk estimates were non

- definitive ( i.e ., the EC 50 

### or LC 50 

### values exceeded the highest concentration tested) for freshwater and estuarine/ma rine fish and aquatic nonvascular plants

, suggest ing that the toxicity of the compound to these taxa may be limited by its solubility (3.3 mg/L)

.

Aquatic exposure estimates are based on EECs obtained using the SWCC

. These EECs are typically regarded as represent ing conservative estimates of exposure because the input value for the application rate is the labeled maximum, the entire watershed is assumed to be cropped and treated, the weather pattern producing the highest concentrations with a 10

- year retu rn frequency

### 43 is used , and the geographic location of use is regarded as representative of high

- end potential for pesticide runoff. Methoxyfenozide has been registered for use in the U.S. for 15 years on a broad range of use sites. Given that methoxyfenozi de is persistent and mobile and that the use pattern involves frequent, repeated applications throughout the growing season, the assumptions built into the SWCC may not be considered conservative for all use sites.

In TFD studies performed on sand (WA and GA), loamy sand (CA), and loam (TX) soils, methoxyfenozide applied to fields dissipated with DT 50 

### s (times for 50% dissipation of the parent) ranging from 92 days to 327 days. Methoxyfenozide was detected as deep as 36 in ch es in the soil in these studies, at concentrations up to 0.039 mg/kg soil (39 μg/kg soil), providing evidence of leaching. In the surface water monitoring study in lotic and lentic water bodies (MRID 49340301 ), peak levels of methoxyfenozide ranged from 0.845 μg/L (lentic) to 1.31 μg/L (lotic). Compared to the EECs for methoxyfenozide in surface water, these values are more than 100X lower than peak EECs estimated with EFED’s models (see Table 7 )

.

F or all of the registered uses of methoxyfenozide, R Qs for freshwater invertebrates exceed the Agency’s levels of concern (LOCs) for acute risk to listed (LOC=0.05) and non

- listed (LOC=0.5) species. RQs also exceed the chronic risk LOC for freshwater invertebrates (LOC=1) for all of the registered uses ( Table 3 ). Except for the use of methoxyfenozide on grass forage and bushberries, RQs exceed the Agency’s acute risk LOCs for listed and non

- listed species of estuarine/marine

invertebrates

. Finally

, for all registered uses, chronic risk RQs for estuarine/marine invertebrates exceed the Agency’s LOCs.

Uncertainties Acute RQs for freshwater invertebrates ( Table 13 ) may underestimate risks since the EC 50 

### for the more sensitive midge was approximated using an ACR for the freshwater invertebrate D. magna

rather than an experimentally derived EC 50



### . Additionally, it is important to note that if RQs for

freshwater inver tebrates are calculated using the D. magna EC 50 

### of 3.7 mg a.i./L and the NOAEC of 0.20 mg a.i./L instead of using the ACR representing the midge, LOCs a re not exceeded (acute RQ=0.05/cotton , chronic R Q=0.9 ), indicating that the likelihood of adverse effect to similarly

sensitive aquatic invertebrates from the registered use s of methoxyfenozide is low. F or acute and chronic exposures of marine/estuarine and freshwater aquatic invertebrates, risks would be lower

than levels of concern if monitoring dat a were used in place of EECs . Alternatively, risks could

be underestimated since monitoring data may not represent peak concentrations

.

B ecause there w ere no mortalit ies or sub

- lethal effects at the highest treatment levels tested in the

freshwater fish and estuarine/marine fish acute toxicity studies, RQ values for acute exposures are not included in the Risk Estimation section of this ass essment. However, estimates of acute risk for fish can have value in characterizing risk overall. RQs shown here are based on the conservative assumption that the highest concentrations tested in the acute toxicity studies represent endpoints ( i.e ., LC 50 

### = 4.2 mg a.i./L for freshwater fish and LC 50 

### = 2.8 mg a.i./L for estuarine/marine fish). A similar assumption can be made for aquatic plants (EC 50 

### = 3.4 mg a.i./L for freshwater algae)

. As stated earlier, in some cases the non

- definitive acute toxicity endpoint suggests that the potential acute toxicity of methoxyfenozide may be limited by the chemical’s solubility (3.3 mg/L

at 25 o 

### C). U sing the peak aquatic EEC for aerial application to cotton ( 0. 1 8 5 m g a.i./L) , all of the se

### 44 acute RQs (freshwater fish R Q = 0.0 4 ; estuarine/marine fish RQ = 0.0 6 ; freshwater algae RQ =

0.0 5 ) would be below the Agency's acute risk LOCs. The actual risks would be lower because no effects were observed at the highest treatment levels tested. This analysis is consistent with th e absence of aquatic incidents for methoxyfenozide in EPA’s incident reporting databases and our findings for chronic risks to freshwater and estuarine/marine fish, i.e ., the RQs do not exceed the Agency’s LOCs for listed or non

- listed species.

No data are available to assess the potential risks of methoxyfenozide exposure to aquatic vascular plants; however, as discussed earlier in Section 4.1.1.3, given that aquatic vascular plant data for tebufenozide did not result in definitive toxicity, the mode of action of methoxyfenozide as an insect growth regulator and that toxicity data for nonvascular aquatic plants did not demonstrate adverse effects up to the solubility limit (3.3 mg/L) of the compound, the current information does not suggest that there wo uld be adverse effects on plants from exposure to methoxyfenozide

. Finally, there are no reported plant incidents in EFED’s incident databases.

Therefore, the likelihood of direct adverse effects to fish and aquatic

- phase amphibians as well as

aqu atic plants from exposure to methoxyfenozide as a result of the registered uses is expected to be low. However, the extent to which fish and aquatic

- phase amphibians are indirectly affected by direct effects on aquatic invertebrates is uncertain.

4.2.2 Risks to Terrestrial Vertebrates and Plants

On an acute exposure basis, methoxyfenozide is classified as practically non

- toxic to birds,

mammals and adult honey bee s.

Because no mortality or sub

- lethal effects were observed at the highest treatment levels tested in

the avian acute oral and sub

- acute dietary studies, standard RQ values a re not includ ed in the Risk

Estimation section of this assessment. In order to gain a better understanding of how the EECs for the maximum methoxyfenozide application rates relate to the toxicity data currently available for birds, the T

- REX model was used to calculate RQs , shown here, using the conservative assumption that the highest values tested in the avian acut e toxicity studies represent endpoints ( i.e ., acute oral

LD 50 

### = 2,250 mg/kg

- bw and sub

- acute dietary LC 50 

### = 5

, 87 0 mg/kg diet for bobwhite quail ). In this analysis , none of the RQs exceeds the Agency’s acute risk LOC for listed (LOC=0.1) or non

- listed speci es (LOC = 0.5 ). The actual risk s would be lower because no effects were observed at the highest treatment levels tested. A s discussed previously in the Risk Estimation section, f or chronic risk, RQs for birds in several forage categories are all below the Agency’s chronic risk LOC

. Therefore, the potential for adverse effects to birds (terrestrial

- phase amphibians and reptiles) from acute, sub

- acute, or chronic exposure to methoxyfenozide from the registered uses is considered

low. T he extent to which bird s , terrestrial

- phase amphibians and reptiles that depend on freshwater aquatic invertebrate species may be indirectly affected is uncertain.

Similarly f or mammals, because there was no mortality or sub

- lethal effects at the highest

treatment levels teste d in the acute oral toxicity study with rats , the standard acute RQ values a re

not includ ed in the Risk Estimation section of this assessment. U sing the conservative as sumption that the highest value tested in the acute toxicity study represent s the endpoi nt ( i.e ., acute oral LD 50

### 45 =5,000 mg/kg

- bw), acute RQs < 0.01 for all of the assessed registered uses and do not exceed the Agency’s acute risk LOC s for mammals. The actual risk s would be lower since no acute mortality

effects were observ ed at the highest treatment levels tested. This analysis is consistent with our findings on chronic risks to mammals, i.e.

, exposure to rats did not result in adverse effects up to

the 20,000 ppm dose level (LOAEC >20,000 ppm , highest dose tested) in a 2

- generation reproduc tive toxicity study. The NOAEC from this study is 20 ,000 ppm (or mg a.i./kg

- diet )

.

In the Risk Estimation section of this assessment, c hronic risk to mammals w as estimated by comparing the NOAEC ( 20 ,000 mg a.i./kg

- diet) to upper

- bound exposure values fro m T

- REX. As shown in Table 19, RQ s for all of the uses are below than 0. 01

, and thus, do not exceed the chronic

risk LOC (1.0). See Appendix C for details.

Therefore, the likelihood of direct adverse effects to mammals from acute and chronic exposure s to methoxyfenozide from registered uses is considered low.

No data are available to assess the potential risks of methoxyfenozide exposure to terrestrial plants; however, as discussed in Section 3.3.2, terrestrial plant data for the IGR tebufenozide can be used to inform the potential toxicity of methoxyfenozide to terrestrial plants and indicate that the

likelihood of adverse effects to plant s from exposure to methoxyfenozide is considered low (see

Section 2.0 ) . Also, there are no reports in EFED’s incident data bases of plant damage resulting from exposure to methoxyfenozide.

4.2.3 Risks to Terrestrial Invertebrates

M ethoxyfenozide is registered on a number of bee

- attractive crops 26 

### including almonds (tree nuts), cotton, berries, citrus, fruiting vegetables, and can be applied to these crops during bloom , when

bees are active ly foraging

. Based on the current use pattern s for this chemical, i t is likely that non

target terrestrial invertebrates are exposed to methoxyfenozide . T he residue study in honey bee

colonies discussed in Section 3.2.3.2 provides evidence of methoxyfenozide exposure to honey

bees in matrices relevant to honey bees ( i.e ., pollen and nectar) , even at a n application rate tha t is

half the maximum rate listed on labels (0.19 lb a.i./Acre)

.

Risks for larval honey bees were initially calculated using the more conservative model

- generated

value s for exposure and were further refined based on empirical exposure data from the residue study in almonds. U sing the maximum application rate and the model

- generated EEC, the RQ (1.4 )

exceeds the acute risk LO C ; however, r efined exposure estimates from the residue study in

almonds and using a lower application rate result s in RQs that do not exceed the acute ris k LOC

for bee larvae

.

As discussed earlier, methoxyfenozide does not appear to be acu tely toxic to adult honey bees, and

the submitted toxicity d ata for honey bee colonies indicate that the compound does not adversely

affect colony brood development and/or overwintering survival , although some c onf ounding

effects were noted in the field

- based studies with whole colonies

. The semi

- field honey bee brood

26 Attractiveness of Agricultural Crops to Pollinating Bees for the Collection of Nectar and/or Pollen. Available at:
http://www.ree.usda.gov/ree/news/Attractiveness_of_Agriculture_crops_to_pollinating_bees_Report

- FINAL.pdf

### 46 study involved feeding bees sucrose containing 101 mg methoxyfenozide/L sucrose syrup w hile the longer

- term colony overwintering study fed bees different concentrations of methoxyfenozide, ranging from 6.25

- 100 mg methoxyfenozide/L sucrose syrup

. T hese test concentrations were fed to adult bees and do not ensure that larval honey bees were e xposed to the test substance ; however, this uncertainty would apply to methoxyfenozide residues resulting from actual use as well

.

The treatment levels used in the two field studies are s ubstantially higher than those used in the laboratory

- based acute larval toxicity study in which the LD 50 

### was determined to be 3.69 μ g a.i./larva

. Although the screening

- level assessment, based on maximum label application rate

, shows risks that exceed the acute risk LOC for honey bee larvae, the field based studies do n ot indicate an adverse effect to brood development and/or colony overwintering success. Refinements using measured residues in pollen/nectar reduced RQ values below the acute risk LOC; however, these refinements were based on residue levels when methoxyfe nozide was applied at half the maximum application rate. There is uncertainty regarding the extent to which

the treatment concentrations in sucrose solutions used to treat the test colonies are representative of those resulting from the use of methoxyfeno zide at the maximum application rate.

It is unclear why effects were manifest ed in the laboratory study but not in semi

- field, colony

- level

studies. In a real

- world setting , as colony

- level studies are designed to reflect, the larval diet during early stages of development consist s largely of royal jelly, a secretion produced by the hypopharyngeal glands of nurse bees . It is possible that the concentration of methoxyfenozide in the royal jelly produced in the hive, where adult bees were feed sucrose syrup containing methoxyfenozide, was lower in concentration than what was fed directly to the larvae in the laboratory

- based study. Also, t he laboratory

- based study involve d a single exposure to methoxyfenozide while the duration o f exposure in the colony

- level studies was longer. There were confounding issues in both types of studies . Additional laboratory

- based toxicity data would be useful to resolve whether the toxicity expressed after a single dose is reflected in a longer

- ter m study. The 21

- day larval toxicity test developed by the Organization for Economic Cooperation and Development would provide a means of addressing this uncertainty as it is a repeat dose study that extends through adult emergence.

Methoxyfenozide has be en associated with six bee kill incident reports to EPA since 2011. Although methoxyfenozide was identified in the se reports , other pesticides were also in use at the

time of these incidents. While there is uncertainty regarding the potential effects of complex tank mixtures involving methoxyfenozide in use by growers, the available laboratory and field data do not indicate a linkage between the losses reported in bee kill incidents and methoxyfenozide as effects were typically associated with adult bee m ortality and the laboratory/field studies indicate that methoxyfenozide is practically non

- toxic to adult bees.

While lepidopteran pests are the target for methoxyfenozide use, lepidopterans also include non

target valued and beneficial moths and butterf lies

, includ ing unlisted species ( e.g ., the monarch butterfly ) and listed species ( e.g ., Karner blue butterfly ) . There is uncertainty surrounding the extent of exposure of non

- target lepidopterans to methoxyfenozide. A pplications in areas that overlap with habitat or feeding areas for these lepidopterans are potential threats, depending on the time of year and other factors.

### 47 4.3. Conclusions

While methoxyfenozide is expected to persist in the environment and move to surface water via runoff/erosion, data on both fish and invertebrates indicate that the compound does not bioconcentrate and it depurates relatively quickly once organism s are no longer exposed. A monitoring study conducted using lentic (static) and lot ic (flowing) water bodies in Califo rnia, Mississippi, and Michigan showed no apparent accumulation of methoxyfenozide in benthic

sediment s and the water columns of surface water at any monitoring sites. T he frequency of sampling in the study was less than the use intensity and duration reflected in modeling , therefore the EECs values may be conservative

. Available data indicate that for both freshwater and estuarine/marine fish, the toxicity of methoxyfenozide appears limited by its solubility in water where no adverse effects ( i.e ., mortality or sublethal effects) were observed on fish following acute exposure to the compound up to its solubility limit.

For aquatic organisms, the screening

- level assessment concludes that most of the registered uses of methoxyfenozide result in potential acute risks of concern for listed and non

- listed freshwater

invertebrates and listed estuarine/marine invertebrates . Additionally, most registered uses result in potential chronic risks to freshwater and marine/ estuarine invertebrates.

For terrestrial organisms, no acute or chronic risks of concern are identified for birds, terrestrial

phase amphibians

, reptiles or mammals. T here are data to indicate that lepidopteran species of

terrestrial invertebrates a re sensitive to methoxyfenozide. A lthough available acute toxicity data do not indicate potential risk to adult honey bees , it now appears that larval honey bees may be sensitive to methoxyfenozide under the laboratory conditions tested

. A cute toxicity data for larval honey bees combined with exposure calculated using default (conservative) assumptions

, Tier 1 risk estimates exceed the acute risk LOCs for larval honey bees ; however, when risk estimates were refined using measured concentration, the RQ no long er exceeds the acute risk LOC. Laboratory

- based chronic toxicity data for larval honey bees would increase the confidence in risk

conclusions and address uncertainties about the potential risk to terrestrial invertebrates and lead

to more robust risk con clusions

. Specifically, a 21

- day larval toxicity study of methoxyfenozide which extends through adult emergence would help to address uncertainties.

Finally, the likelihood of adverse effects to plants from exposure to methoxyfenozide is considered

to be low

.

4.4

. Endocrine Disruptor Screening Program

As required by FIFRA and the Federal Food, Drug, and Cosmetic Act (FFDCA), EPA reviews numerous studies to assess potential adverse outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, reproductive, and general or systemic toxicity. These studies include endpoints which may be susceptible to endocrine influence, including effects on endocrine target organ histopathology, organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and chronic studies that assess growth, developmental and

### 48 reproductive effects in different t axonomic groups. As part of this preliminary risk assessment

, EPA reviewed these data and selected the most sensitive endpoints for relevant risk assessment scenarios from the existing hazard database. However, as required by FFDCA section 408(p)

, methoxyfenozide is subject to the endocrine screening part of the Endocrine Disruptor Screening Program (EDSP).

EPA has developed the EDSP to determine whether certain substances (including pesticide active and other ingredients) may have an effect in humans or wildlife similar to an effect produced by a “naturally occurring estrogen, or other such endocrine effects as the Administrator may designate.” The EDSP employs a two

- tiered approach to making the statutorily required

determination s. Tier 1 consists of a battery of 11 screening assays to identify the potential of a chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal

systems. Chemicals that go through Tier 1 screening and are found to have th e potential to interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA will determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 testing is designed to identify any adverse en docrine

- related effects caused by the substance, and establish

a dose

- response relationship between the dose and the E, A, or T effect.

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between October 2009 and February 2010, EP A issued test orders/data call

- ins for the first group of 67 chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. A second list of chemicals identified for EDSP screening was published on June 14, 2013 [1] 

### and includes some pes ticides scheduled for registration review and chemicals found in water

. Neither of these lists should be construed as a list of known or likely endocrine disruptors. Methoxyfenozide is not on List 1. For further information on the status of the EDSP, the policies and procedures, the lists of chemicals, future lists, the test guidelines and Tier 1 screening battery, please visit EPA’s EDSP website [2]



### .

4.5. Federally Threatened and Endangered (Listed) Species of Concern

Consistent with the Agency’s respons ibility under the Endangered Species Act (ESA), the Agency will evaluate risks to listed species from registered uses of pesticides during Registration Review. The process for evaluating potential risks to listed species is further described at http://www.epa.gov/oppfead1/endanger/litstatus/riskasses.htm

.

In 2006, EFED completed an interim endangered species risk assessment for the Karner Blue Butterfly ( Lycaeides melissa samuelis ) for the use of methoxyfenozide on cranberries in

Wisconsin 27



### . E ndangered species protection bulletin s for the use of methoxyfenozide in areas where use of methoxyfenozide may overlap with habitat of the Karner Blue Butterfly are posted to the Ag ency’s website (See: http://www.epa.gov/oppfead1/endanger/bulletins.htm and http://54.84.207.203/BLT_Public/ .)

[1] See http://www. regulations.gov/#!documentDetail;D=EPA

- HQ

- OPPT

- 2009

- 0477

- 0074 for the final second list of

chemicals.

[2] Available: http://www.epa.gov/endo/

27 US EPA, 2006.

### 49 5 . References

FAO, 2000. Food and Agriculture Organization of the United Nations. Pesticide Disposal Series 8. Assessing Soil Contamination: A Reference Manual. Appendix 2. Parameters of pesticides that influence processes in the soil. Editorial Group, FAO Information D ivision: Rome, 2000. http://www.fao.org/docrep/003/X2570E/X2570E00.htm

.

Fletcher, J.S., J.E. Nellesson and T. G. Pfleeger. 1994. Literature review and evaluation of the

EPA food

- chain (Kenaga) nomogram, an instrument for estimating pesticide residues on plants. Environ. Tox. And Chem. 13(9):1383

- 1391.

Goring, C.A. I.; Laskow ki; D.A., Hamaker, J.H.; and Meikle, R.W. 1975. Principles of pesticide degradation in soil. pp. 135

- 172 in (Haque, R. and Freed, V.H. eds.) Environmental dynamics of pesticides. Plenum Press, NY.

Hoerger, F. and E.E. Kenaga. 1972. Pesticide residues on p lants: correlation of representative data as a basis for estimation of their magnitude in the environment. IN: F. Coulston and F. Corte, eds., Environmental Quality and Safety: Chemistry, Toxicology and Technology. Vol 1. Georg Theime Publishers, Stuttgart , Germany. Pp. 9

- 28.

Intrepid ® 

### 2F Master Label, 2013. Registration Number 62719

- 442. Amended 04

- 19

- 13. Provided by Registration Division, Office of Pesticide Programs, US EPA. F3B / Intrepid 2F / MSTR

Amend / 04

- 19

- 13. file: Intrepid 2F

- 442 MSTR 12Jul12f. doc

LaLone, C. A., Villeneuve, D. L., Garber, K., Tollefsen, K.E., Ankley, G. T. 2014. Conservation of Lepidopteran Ecdysteroid Receptor Provides Evidence for Butterfly Susceptibility to Diacylhydrazine and Bisacylhydrazine Chemicals. Society of Environme ntal Toxicology and Chemistry 35th Annual Meeting , 11/11/2014 . Vancouver, Canada.

Mommaerts, V. et. al

. 2006. Bumblebees can be used in combination with juvenile hormone analogues and ecdysone agonists ; Ecotoxicology (2006) 15:513

– 52 1.

Shimizu, B., Y. Nakagawa, K. Hattori, K. Nishi mura, N. Kurihara, and T. Ueno, 1997 . Molting hormonal and larvicidal activities of aliphatic acyl analogs of dibenzoylhydrazine insecticides. Steroids 62 (10): 638

- 642.

Trisyono, A., and G. M. Chippendale (1997). Effect of the non

- steroidal ecdysone agonists, methoxyfenozide and tebufenozide, on the European corn borer (Lepidoptera; Pyralidae). J.

Econ. Entomol ., 90: 1486

- 1492. (ECOTOX No.: 64128).

US EPA, 2 004. Overview of the Ecological Risk Assessment Process in the Office of Pesticide Programs. U.S. Environmental Protection Agency, Endangered and Threatened Species Effects Determinations, Office of Prevention, Pesticides and Toxic Substances Office of Pe sticide Programs, Washington, D.C. 100 pgs. January 23.

### 50 US EPA, 2006. Interim Risk Assessment for the Karner Blue Butterfly for the Use of Methoxyfenozide on Cranberries in Wisconsin. U.S. Environmental Protection Agency, Office Fate and Effects Division, October 19, 2006.

US EPA. 2009. Guidance for Selecti ng Input Parameters in Modeling the Environmental Fate and Transport of Pesticides. U.S. Environmental Protection A gency, Office Fate

and Effects Division, Oct. 22, 2009. Online at: http://www.epa.gov/oppefed1/models/water/input_parameter_guidance.htm

US EPA, 2011. Review of Addendum to Site Selection Report with Recommended Alternate Sampling Sites for Lentic Water Bodies in California (MRID 47809904) (MRID: 478099

- 04).

From C

. Peck (EFED) and M

. Echeverria (EFED) to C

. Myers (RD) and R

. Gebken (PRD). DP barcode 394308. October 12, 2011.

US EPA, 2012a. Screening Level Usage Analysis for Methoxyfenozide. Biological and Economic Analysis Division, Offic e of Pesticide Programs, US EPA; Date: June 19, 2012.

US EPA. 2012. Guidance for Selecting Input Parameters for Modeling Pesticide Concentrations in Groundwater Using the Pesticide Root Zone Model. Office of C hemical Safety and Pollution Prevention, Offic e of Pesticide Programs, Environmental Fate and Effects Division, and Health Canada Pesticide Management Regulatory Agency, Oct.15, 2012.

US EPA

, 2013. Environmental Fate and Ecological Risk Assessment for Proposed Use of Methoxyfenozide on Herb Subgroup 19A (except chives), Dates, Sorghum, Fruiting Vegetable Group 8

- 10, Pome Fruit Group 11

- 10, Berry Subgroups 13

- 07 A, F & G, Tropical Tree Fruits AND Section 18 Emergency Exemption Petition for Use of Methoxyfenozide to Control Carob

Moth o n Dates. Environmental Fate and Effects Division

, Office of Pesticide Programs, US

EPA

. DP Barcodes: 407284, 407808, 410683. June 13, 2013

.

US EPA. 2013a. Methoxyfenozide: Review of Interim Report on Surface Water and Sediment Monitoring (MRID 49050001). Office of Chemical Safety and Pollution Prevention, Office of Pesticide Programs, From Environmental Fate and Effects Division (EFED) to Registration Division (RD); from C

. Peck to M

. Suarez. March 26, 2013.

US EPA. 2013b. Registration Review: Preliminary Problem Formulation for Environmental Fate, Ecological Risk, Endangered Species, and Human Health Drinking Water Exposure Assessments for Methoxyfenoxide. DP Barcode: D404482. Date: April 25, 2013.

US EPA, 2014. Guidance for Assessing Pesticide Risks to Bees. US EPA, Office of Pesticide Programs, Health Canada Pest Management Regulatory Agency, and California Department of Pesticide Regulation. June 19, 2014.

USDA Crop Profiles. Available online at: http://www.ipmcenters.org/cropprofiles/CP_form.cfm

### 51 Appendix A: Summary of Registered Uses of Methoxyfenozide (May , 2015)

Use Method of Applicatio

n Min Single App rate (lb a.i./A) Max Single App Rate (lb a.i./A) Max #Apps/

Year Max App

rate/Year

(lb a.i./ A/Yr) MRI (days) Reg

Numbers

Brassica (Cole) Leafy Vegetables (Crop Group 5) 2 Ground,

aerial 0.078 0.234 6 1 4 62719

- 666

Bushberries (Subgroup (13

- 07B1), Aronia Berry, Buffalo Currant, Chilena Giava, European Barberry, Highbush Cranberry, Honeysuckle, Jostaberry, Junerberry, Lingonberry, Native Currant, Salal, Sea Buck thorn, and Cultivars and/or Hybrids of Each Ground,

aerial 0.06 0.25 3 0.75 7 62719

- 442

Bushberries (Subrgroup 13B) Ground,

aerial 0.078 0.234 3 0.75 7 62719

- 666

Cilantro Leaves, Brassica (Cole) Leafy Vegetables (Crop Group 5) 2 , Leafy Vegetables (Crop Group 4) 3

,

Leaves of Root and Tuber Vegetables (Crop Group 2) 4

, and Turnip Greens Ground,

aerial 0.06 0.25 NS 1 NS 62719

- 442

Cilantro Leaves Ground,

aerial 0.078 0.234 5 1 4 62719

- 666

Citrus Fruits (Crop Group

10

- 10) 5 Ground 0.12 0.25 NS 1 14 62719

- 442

Citrus Fruits (Crop Group

10

- 10) 5 Ground 0.117 0.234 3 0.94 7 62719

- 442

Corn (Field, Sweet, Seed) Ground,

aerial 0.06 0.25 NS 1 5 62719

- 442

Corn (Field, Sweet, Seed) Ground,

aerial 0.078 0.234 3

- Field

Corn

6

- Sweet,

Seed

Corn 2, 4 62719

- 666

Cotton Ground,

aerial 0.06 0.16 NS 1 10 62719

- 442

Cotton Ground,

aerial 0.05 0.4 2 1 10, 14 62719

- 438

Cotton Ground,

aerial 0.078 0.156 6 1 4 62719

- 666

Cranberry Ground, aerial, chemigatio

n 0.16 0.25 NS 1 10 62719

- 442

### 52 Cranberry Ground, aerial, chemigatio

n 0.137 0.234 6 1 7 62719

- 666

Cucurbit Vegetables (Crop Group 9) 7 Ground,

aerial 0.078 0.156 4 per

season 1 7 62719

- 666

Cucurbit Vegetables (Crop Group 9) 7 Ground,

aerial 0.06 0.16 4 1 7 62719

- 442

Foliage of Legume Vegetables (Except Soybean) Ground,

aerial 0.078 0.234 4 1 7 62719

- 666

Fruiting Vegetables (Crop Group 8) 8 and Okra Ground,

aerial 0.06 0.25 NS 1 7, 14 62719

- 442

Fruiting Vegetables (Crop Group 8) 8 and Okra Ground,

aerial 0.078 0.234 6 1 4 62719

- 666

Globe Artichoke Ground,

aerial 0.06 0.25 4 1 7 62719

- 442

Globe Artichoke Ground,

aerial 0.078 0.234 4 1 7 62719

- 666

Grape Ground,

aerial 0.117 0.234 5 0.75 4 62719

- 666

Grape Ground,

aerial 0.12 0.25 NS 0.75 10, 18 62719

- 442

Grass Forage, Fodder, and

Hay (Crop Group 17) Ground,

aerial 0.06 0.12 NS 0.5 NS 62719

- 442

Green Onion (Subgroup 3

- 07B) 9 Ground,

aerial 0.06 0.12 6 1 10 62719

- 442

Green Onion, Leek, and

Shallot Ground,

aerial 0.078 0.176 5 1 4 62719

- 666

Leafy Vegetables (Except Brassica) (Crop Group 4) Ground,

aerial 0.078 0.234 6 1 4 62719

- 666

Leaves of Root and Tuber Vegetables (Crop Group 2) and Turnip Greens Ground,

aerial 0.078 0.234 6 1 7 62719

- 666

Legume Vegetables (Succulent or Dried) (Crop Group 6) Groun d

, aerial 0.078 0.234 1 , 0.47 7 62719

- 666

Legume Vegetables (Succulent or Dried) (Crop Group 6) 10 and Foliage of Legume Vegetables (Except Soybean) (Subgroup 7A) 11 Ground,

aerial 0.06 0.25 4 1 7 62719

- 442

### 53 Nongrass Forage, Fodder, Straw and Hay (Crop Group 18) 12 Ground,

aerial 0.06 0.12 NS 0.5 NS 62719

- 442

Ornamentals Ground, aerial,

convention

al spray, chemigatio

n 0.06 0.25 4 0.5 14 62719

- 442

Peanut Ground,

aerial 0.09 0.16 3 1 7 62719

- 442

Peanut Ground,

aerial 0.078 0.156 3 1 7 62719

- 666

Peppermint and Spearmint Ground,

aerial 0.156 0.234 4 1 4 62719

- 666

Pineapple Ground 0.06 0.1 4 0.44 7 62719

- 442
Pome Fruits (Crop Group 11) 13 Ground,

aerial 0.09 0.25 NS 1 10, 18 62719

- 442

Pome Fruits Ground,

aerial 0.15 0.3 3 1 10, 14, 15, 18 62719

- 438

Pome fruits (Crop Group 11) Ground,

aerial 0.088 0.25 4 1 10 62719

- 666

Pomegranate Ground,

aerial 0.12 0.25 NS 1 14, 18 62719

- 442

Pomegranate Ground,

aerial 0.117 0.234 3 0.547 10 62719

- 666

Popcorn Ground,

aerial 0.06 0.12 NS 1 10 62719

- 442

Popcorn Ground,

aerial 0.078 0.125 6 1 2, 4 62719

- 666

Root Vegetables 14 Ground,

aerial 0.12 0.25 NS 1, 0.5 (radishes) 14 62719

- 442

Root Vegetables (Subgroups

1A, 1B) and Tuberous and Corm Vegetables (Except

Potato) (Subgroup 1D) Ground,

aerial 0.088 0.234 3 * 1

, 0.94,

0.1 14 62719

- 666

Soybean Ground,

aerial 0.06 0.12 4 1 7 62719

- 442

Soybean Ground,

aerial 0.078 0.125 4 0.545 4 62719

- 666

Spearmint and Peppermint Ground,

aerial 0.16 0.25 NS 1 14, 21 62719

- 442

### 54 Stone Fruits

-- Apricots, Nextarines, Peaches, Plums, Prunes, and Their Hybrids Ground,

aerial 0.12 0.25 NS 1 10, 14,

18 62719

- 442

Stone Fruits

-- Cherries (Sweet and Sour) Ground,

aerial 0.12 0.25 NS 0.9 10, 14,

18 62719

- 442

Stone Fruits (Crop Group 12) Ground,

aerial 0.117 0.234 4 1 7 62719

- 666

Strawberry Ground,

aerial 0.09 0.19 1 1 10, 14 62719

- 442

Strawberry Ground,

aerial 0.088 0.176 5 1 4 62719

- 666

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Almonds Ground,

aerial 0.12 0.38 NS 1 10, 14,

18 62719

- 442

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Almonds Ground,

aerial 0.117 0.352 4 1 7 62719

- 666

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Hazelnuts Ground,

aerial 0.12 0.25 NS 1 10, 14,
18, 21 62719

- 442

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Hazelnuts Ground,

aerial 0.117 0.234 4 1 7 62719

- 666

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Pecans Ground,

aerial 0.06 0.12 NS 1 14 62719

- 442

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Pecans Ground,

aerial 0.078 0.125 4 1 7 62719

- 666

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Walnuts Ground,

aerial 0.12 0.38 NS 1 14, 21 62719

- 442

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Walnuts Ground,

aerial 0.117 0.352 4 1 7 62719

- 666

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Not Listed Ground,

aerial NS NS NS 1 10, 20 62719

- 442

Tree Nuts (Crop Group 14) 16

and Pistachios

-- Not Listed Ground,

aerial NS NS 4 1 7 62719

- 666

Tropical Tree Fruits 17 Ground,

aerial 0.16 0.25 5 1 X 18 62719

- 442

Tropical Tree Fruits

- Acerola, feijoa, guava, jaboticaba, passionfruit,

starfruit, wax jambu Ground,

aerial 0.137 0.234 3 1 6 62719

- 666

Tropical Tree Fruits

- Avocado Ground,

aerial 0.137 0.234 3 1 6 62719

- 666

Tropical Tree Fruits

- Black

sapote, canistal, mamey

sapote, mango, papaya,

sapodilla, star a pple Ground,

aerial 0.137 0.234 3 1 10 62719

- 666

### 55 Tropical Tree Fruits

- Longan, lychee, pulasan, rambutan, Spanish lime Ground,

aerial 0.137 0.234 3 1 10 62719

- 666

Tuberous and Corm Vegetables (except Potato) (Subgroup 1D) 19 Ground,

aerial 0.09 0.16 3 1 14 62719

- 442

Sweet Potato Ground,

aerial 0.09 0.16 1 0.16 7 62719

- 442

Sweet Potato Ground,

aerial 0.09 0.16 3 0.48 7 62719

- 442

Sweet Potato Ground,

aerial 0.09 0.16 3 0.48 7 62719

- 442

Non

- Bearing Citrus (Including Nurseries) Ground,

aerial 0.09 0.18 4 0.72 7, 14 62719

- 442

Citrus Fruits Ground,

aerial 0.12 0.25 NS 1 14 62719

- 442

Dry Beans (Colorado) Aerial 0.12 0.25 NS 1 14 62719

- 442

Sugarbeet (Colorado) Aerial 0.12 0.25 NS 1 14 62719

- 442

Dry Beans (Wyoming) Aerial 0.12 0.25 4 1 7 62719

- 442

Sugarbeet (Wyoming) Aerial NS 1 14 62719

- 442

Dates Ground 0.16 0.31 NS 1 10 62719

- 442

Herbs (Fresh and Dried) (Except Chive) Ground,

Aerial 0.06 0.25 NS 1 10 62719

- 442

Caneberries Ground,

Aerial 0.06 0.25 3 0.75 7 62719

- 442

Sorghum Ground,

Aerial 0.12 0.16 NS 0.75 NS 62719

- 442

1 Bushberries (subgroup 1307B) including black currant, elderberry, gooseberry high bush blueberry, huckleberry, lowbush blueberry, red currant

2 Brassica (cole) leafy vegetables (crop group 5) including broccoli, broccoli raab, Brussels sprouts, cabbage, cauliflower, ca valo broccolo, Chinese broccoli, Chinese cabbage (bok choy, napa), Chinese mustard cabbage (gai choy), collards, kale, kohlrabi,

m izuna, mustard greens, mustard spinach, rape greens.

3 Leafy vegetables (except Brassica) (crop group 4) including amaranth, arugula, cardoon, celery, celtuce, chervil, Chinese cel ery, corn salad, dandelion, dock, edible

- leaved chrysanthemum, endive (escaro le), florence fennel, garden cress, garden purslane, garland chrysanthemum, lettuce (head, leaf), New Zealand spinach, orach, parsley, radicchio, rhubarb, spinach, Swiss chard, upland cress, vine spinach, winter purslane.

4 Leaves of root and tuber vegetables (crop group 2) including bitter cassava, black salsify, carrot, celeriac, chicory, dasheen, edible burdock, garden beet, parsnip, oriental radish, radish, rutabaga, sugarbeet, sweet cassava, sweet potato, tanier, true yam, turnip, and turnip

- roo ted chervil

5 Citrus fruits (crop group 10

- 10) including Australian desert lime, Australian finger lime, Australian round lime, brown river finger lime, calamondin, citron, citrus hybrids, grapefruit, Japanese summer grapefruit, kumquat, lemon, lime, Medite rranean mandarin, mount white lime, New Guinea wild lime, pummelo, russell river lime, satsuma mandarin, sour orange, sweet lime, sweet orange, tachibana orange, Tahiti lime, tangelo, tangerine (Mandarin), tangor, trifoliate orange, uniq fruit, cultivars, varieties and/or hybrids of these

6 Suppression only. Use a higher rate in the rate range and ensure thorough coverage. Tank mixing Intrepid ® 2F with other products registered for fall armyworm control in cotton (e.g., pyrethroids, spinosad, or others) ha s been shown to improve control. Consult your Dow AgroSciences’ representative, extension service specialist, certified crop advisor or state agricu ltural experiment station for any additional local use recommendations for your area.

7 Cucurbit vegetables (crop group 9) including balsam apple, balsam pear, bitter melon, chayote (fruit), Chinese cucumber, Chinese waxgourd (Chinese preserving melon), citron melon, cucumber, edible gourd (including Chinese okra, cucuzza, hechima, hyotan), gherkin, muskmelon (i ncluding cantaloupe, casaba, crenshaw melon, golden pershaw melon, honey balls, honeydew melon, mango melon, persian melon, pineapple melon, santa claus melon, snake melon, true cantaloupe), pumpkin, summer squash (including crookneck squash, scallop squas h, straightneck squash, vegetable marrow, zucchini), winter squash (including acorn squash, butternut squash, calabaza, hubbard squash, spaghetti squash), watermelon

### 56 8 Fruiting vegetables (crop group 8) including eggplant, groundcherry, pepino, pepper (bel l, chili, cooking, sweet), pimento, tomatillo, tomato

9 Green onion (subgroup 3

- 07B) including beltsville bunching onion, Chinese chive (fresh leaves), chive (fresh leaves), elegans hosta, fresh onion, fritillaria leaves, green onion, kurrat, lady’s leek, l eek, macrostem onion, shallot (fresh leaves), tree onion (tops), wild leek

10 Legume vegetables (succulent or dried) (crop group 6) including asparagus bean, blackeyed pea, Cajanus spp. (pigeon pea), Chinese longbean, Cicer arietinum (chick peas, garbanzo b eans), cowpea, green lima bean, jackbean, Lens spp. (lentils), Lupinus spp. (grain lupine, sweet lupine, white lupine, white sweet lupine), moth bean, Phaseolus spp. (kidney beans, lima beans, mun g beans, navy beans, pinto beans, snap beans, waxbeans), Pis um spp. (dwarf pea, edible

- pod pea, English pea, field pea, garden pea, green pea), runner bean, snap bean, snow pea, soybean (immature seed), southern pea, succulent broad bean, sugar snap pe a, sword bean, Vicia faba (broad beans, fava beans); Vigna spp. (asparagus beans, blackeyed pea, cowpeas), wax bean, yardlong

bean

11 Foliage of legume vegetables (except soybean) (subgroup 7A) including any cultivar of bean and field pea (except soybean)

12 Nongrass forage, fodder, straw and hay (crop group 18) includin g alfalfa, clover, crown vetch, kudzu, lespedeza, lupin, milk vetch, sainfoin, trefoil, velvet bean, vetch

13 Pome fruits (crop group 11) including apple, crabapple, loquat, mayhaw, pear, pear (oriental), quince

14 Root vegetables (subgroups 1A, 1B) includin g black salsify, carrot, celeriac, chicory, edible burdock, garden beet, ginseng, horseradish, parsnip, oriental radish, radish, rutabaga, salsify, skirret, Spanish salsify, sugarbeet, turnip, turnip

- rooted chervil, and turnip

- rooted parsley

15 Stone fruits (crop group 12) including apricot, cherries (sweet, sour), chickasaw plum, damson plum, Japanese plum, nectarine, peach, plum, plumcot, prune (fresh)

16 Tree nuts (crop group 14) including almond, beech nut, Brazil nut, butternut, cashew, chestnut, chinqua pin, filbert (hazelnut), hickory nut, macadamia (bush) nut, pecan, pistachio, walnut (black and English)

17 Acerola, avocado, black sapote, canistal, feijoa, guava, jaboticaba, longan, lychee, mamey sapote, mango, papaya, passionfrui t, pulasan, rambutan, sa podilla, Spanish lime, star apple, starfruit, wax jambu

18 Acerola, Feijoa, Guava, Jaboticaba, Passionfruit, Starfruit, Wax Jambu: Preharvest Interval: Do not apply within 3 days of

harvest. Minimum Re

- treatment Interval: 6 days Avocado: Preharvest Interval : Do not apply within 2 days of harvest. Minimum

Re

- treatment Interval: 6 days Black Sapote, Canistal, Mamey Sapote, Mango, Papaya, Sapodilla, Star Apple: Preharvest Interval: Do not apply within 3 days of harvest. Minimum Re

- treatment Interval: 10 days Lo ngan, Lychee, Pulasan, Rambutan, Spanish Lime: Preharvest Interval: Do not apply within 14 days of harvest. Minimum Re

- treatment Interval: 10 days

19 Tuberous and corm vegetables (except potato) (subgroup 1D) including arracacha, arrowroot, bitter cassava, chayote (root), Chinese artichoke, chufa, dasheen, edible canna, ginger, Jerusalem artichoke, leren, sweet cassava, sweet potato, tanier, tru e yam, turmeric, yam bean



### * Arracacha, arrowroot, bitter cassava, chayote root, Chinese artichoke, chufa, dasheen, e dible canna, ginger, Jerusalem artichoke, leren, sweet cassava, sweet potato, tanier, true yam, turmeric, yam bean, celeriac, edible burdock, Oriental radish, rutabaga, turnip) 4 (Garden beet, sugar beet, black salsify, carrot, chicory, ginseng, horseradis h, parsnip, salsify, skirret, Spanish salsify, turnip

- rooted chervil, turnip

- rooted parsley, radish

### 57 APPENDIX B : Methoxyfenozide and Its Environmental Degradates

Code Name/ Synonym Chemical Name Chemical Structure Study Type Ref.

(MRID) Max%AR (day) Final %AR (study length)

PARENT

Methoxyfenozide CAS No.: 161050

- 58

- 4

Formula:

C 22 H 28 N 2 O 3 MW: 368 g/mol Smile string: Cc1c(OC)cccc1C(= O)NN(C(C)(C)C)C (=O)c2cc(C)cc(C)c

2

MINOR TRANSFORMATION PRODUCTS

RH

- 117236 CAS No.:

Formula:

C 21 H 26 N 2 O 3 MW: 354.45 Smile string: CC1=C(C=CC=C1 O[H])C(=O)NN(C( C)(C)C)C(=O)C2= CC(=CC(=C2)C)C Aerobic aquatic study 446178

- 09 In CA, 15.8% (91 d)
In TX, 6.7% (60 d) In Ca, 3% (365 d) In TX, 1% (365 d)

RH

- 131154 CAS No:

Formula:

C 22 H 26 N 2 O 5 MW: 398.46

Smile string: CC1=C(C=CC=C1 OC)C(=O)NN(C(C )(C)C)C(=O)C2=C C(=CC(=C2)C(O[H ])=O)C Aerobic aquatic study 446178

- 09 <1% (365 d) <1% (365 d)

Anaerobic

aquatic study 446178

- 10 1.1% (119 d) 0.61% (364 d)

Aerobic soil

metabolism 446178

- 08

446178

- 07

441444

- 32 -- 1

- 3% (365 d)

CO 2 CAS No : 124

- 38

- 9

Formula: CO 2 MW: 44.01 g/mol Smile string:

C(=O)=O Aerobic aquatic study 446178

- 09

-- <6% (365)

Anaerobic

aquatic study 446178

- 10

-- 3.2% (364)

Aerobic soil

metabolism 446178

- 08

446178

- 07

441444

- 32 -- 2

- 5% (365 d)

### 58 APPENDIX C : Summary of the Available Eco

- Toxicity Data for Methoxyfenozide.

TABLE C .1. Summary of Submitted Toxicity Data for Methoxyfenozide and Aquatic

Animals.

Taxonomic

Group Study Type Surrogate Species Toxicity Value (all units in

terms of

measured active

ingredient) Acute Toxicity

Classification Source (MRID) Study

Classification

Freshwater

Fish 96

- Hour

Acute Toxicity Rainbow trout Oncorhynchus mykiss LC 50 >4.2 mg/L (No mortality at

the highest

treatment level tested) Moderately

Toxic 441444

- 10 Acceptable

Full Life

Cycle Toxicity Fathead minnow Pimephales promelas NOAEC = 0.53 mg a.i./L

LOAEC = 1.0

(survival) N/A 446177

- 16 Acceptable

Freshwater

Invertebrates 48

- hour

Acute Toxicity Waterflea

Daphnia magna EC 50 = 3.7 mg a.i./L Moderately

Toxic 441444

- 11 Acceptable

Estimate

based on

Acute

- to

Chronic

Ratio 1 Midge

Chironomus

riparius EC 50 = 0.0 6 1 mg a.i./L (mortality) Very highly

toxic N/A 1 N/A 1

Chronic Toxicity Waterflea

Daphnia magna NOAEC = 0.20 mg a.i./L

LOAEC = 0.39 mg a.i./L (survival) N/A 446177

- 14 Acceptable

Chronic

Effects on

Midge

Larvae Midge

Chironomus

riparius NOAEC=0.00 3 1 mg a.i./L (pore water)

LOAEC=0.006 3 mg a.i./L (pore water)

(Delayed emergence and development) N/A 450328

- 01 Supplemental

Estuarine/

Marine Fish 96

- Hour

Acute Toxicity Sheepshead

minnow

Cyprinodon variegatus 96

- hr LC 50 >2.8 mg a.i./L Moderately

Toxic 441444

- 12 Acceptable

Early Life

Stage Toxicity NOAEC = 1.5 mg

a.i./L

LOAEC = 2.6 mg

a.i./L

(growth) N/A 446177

- 12 Currently under

review in EFED

### 59 Taxonomic

Group Study Type Surrogate Species Toxicity Value (all units in

terms of

measured active

ingredient) Acute Toxicity

Classification Source (MRID) Study

Classification

Estuarine/

Marine

Invertebrates 96

- Hour

Shell Depositio

n Eastern oyster

Crassostrea

virginica 96

- hr EC 50 = 1.2 mg a.i./L Moderately

Toxic 441444

- 13 Acceptable

Invertebra

te Life Cycle Toxicity Mysid

Americamysis bahia ( formerly

Mysidopsis

bahia) NOAEC = 0.025 mg a.i./L

LOAEC = 0.051 mg a.i./L (Reduced growth/length) N/A 446177

- 15 Acceptable

Non

- Vascular Aquatic Plants 5

- Day Toxicity

Test Freshwater alga

Pseudokirchneri ella subcapitata ( formerly

Selenastrum capricornutum) EC 50 >3.4 mg

a.i./L

NOAEC= 3.4 mg

a.i./L

No effects at the highest treatment

level tested N/A 446177

- 18 Acceptable

1 This endpoint is based on an acute to chronic ratio (ACR) using acute and chronic data from daphnids and chronic data from midges.

### 60 TABLE C .2. Summary of Available Toxicity Data for Methoxyfenozide and Terrestrial

Animals.

Taxonomi c Group Study Type Surrogate Species Toxicity Value (all units in

terms of

measured active

ingredient) Acute Toxicity

Classification Source (MRID) Study

Classification

Birds Acute Oral Toxicity Northern bobwhite quail

Colinus virginianus LD 50 >2,250 mg a.i./kg

- bw

No effects at highest treatment

level tested Practically

Non

- Toxic 441444

- 06 Acceptable

Subacute Dietary Toxicity Northern bobwhite quail

Colinus virginianus LC 50 >5,870 mg a.i./kg

- diet

No effects at highest treatment

level tested Practically

Non

- Toxic 441444

- 07 Acceptable

Avian Reproducti ve Toxicity Northern bobwhite quail

Colinus virginianus NOAEC=520 mg a.i./kg

- diet N/A 446177

- 11 Acceptable

Mammals Acute oral Toxicity Rat

Rattus norvegicus LD 50 >5,000 mg a.i./kg

- bw Acute Toxicity Category 4 441444

- 15 Acceptable

2

- Generation Reproducti on Toxicity Rat

Rattus norvegicus NOAE C = 20 ,000

ppm diet (1552 mg/kg)

( Survival ) N/A 446177

- 27 Acceptable

Terrestrial

Invertebrat

es Acute

Contact Toxicity

Honey bee

Apis mellifera LD 50 >100 μg

a.i. /bee Practically

Non

- Toxic 441444

- 29 Acceptable

Dietary Toxicity LC 50 > 100 μg

a.i. /bee Practically

Non

- Toxic 446177

- 17 Supplemental

Brood Study NOAEL = 101 mg a.i./L N/A 450655

- 01 Supplemental

### 61 Appendix D : Example Summary Output of T

- REX (Tree Nuts Use)

TREX MODEL

INPUTS You must enable macros for this spreadsheet to
work correctly

Chemical Identity and Application Information Application

No. Rate Day of Application

Chemical Name: Methoxyfenozide Application Rate (lb ai/acre) 1 0.38 0

Seed Treatment? (Check if yes) FALSE Seeding Rate (lbs/acre) 2 0.38 10

Use: Tree nuts 3 0.24 20

Product name

and form: 4 % A.I. (leading

zero must be

entered for

formulations <1% a.i.): 100.00% 5
Application Rate (lb ai/acre) 0.38 6

Half

- life (days): 35 7
Application Interval (days): 10 8

Number of
Applications: 3 9
Are you assessing applications with

variable rates or

intervals? yes 10

You MUST specify application day in Columns F and G

- you may enter up to 30 applications 11

Assessed Species Inputs (optional, use defaults for RQs for national level assessments) 12

What body weight range is assessed (grams)? Birds Mammal

s 13

Small 20 15 14

Medium 100 35 15

Large 1000 1000

16

Note: Sources of wildlife diet are assumed to be available for less than one year for this model.

Endpoints

### 62 Avian

Endpoint Toxicity

value Indicate test
species

below Optional

Test
Organism Body weight (g) Optional Test
Species Name

LD50 (mg/kg

- bw)

2250.00 1

LC50 (mg/kg

- diet)

5870.00 1

NOAEL (mg/kg

- bw)

1

NOAEC (mg/kg

- diet)

520.00 1

Enter the Mineau et al. Scaling Factor 1.15

Mammalian

Acute Study Chronic Study
Size (g) of mammal used in toxicity study Default rat body weight is 350 grams 350 350

Endpoint Toxicity

value Reference (MRID)

LD50 (mg/kg

- bw) 5000.00 441444

- 15

LC50 (mg/kg

- diet)

Reported Chronic Endpoint 20000.0

0
2 44617727

Is estimated daily dose (mg/kg

- bw)
reported from the available chronic mammal study? (yes or no) no

Enter daily dose (mg/kg

- bw)

Estimated Chronic Daily Dose Equivalent to reported Chronic
Dietary Endpoint 1000 mg/kg

- bw

based on

standard

FDA lab rat

conversion

### 63 Summary of Risk Quotient Calculations Based on Upper Bound Kenaga EECs

Table X. Upper Bound Kenaga, Acute Avian Dose

- Based Risk Quotients

Size Class (grams) Adjusted

LD50 EECs and RQs

Short Grass Tall Grass Broadleaf

Plants Fruits/Pods/

Seeds Arthropods Granivore

EEC RQ EEC RQ EEC RQ EEC RQ EEC RQ EEC RQ

20 1620 .97 258.97 0.1

6 118.70 0.07 145.

67 0.

09 16.1

9 0.01 101.43 0.06 3.60 0.00

100 2063.57 147.68 0.0

7 67.69 0.03 83.0

7 0.

04 9.23 0.00 57.84 0.03 2.05 0.00

1000 2914.87 66.12 0.0

2 30.30 0.01 37.1

9 0.

01 4.13 0.00 25.90 0.01 0.92 0.00

Table X. Upper Bound Kenaga, Subacute Avian Dietary Based Risk Quotients

LC50 EECs and RQs

Short Grass Tall Grass Broadleaf Plants Fruits/Pods/Seeds Arthropods

EEC RQ EEC RQ EEC RQ EEC RQ EEC RQ

5870 227.3

9 0.04 104.2

2 0.0

2 127.91 0.02 14.21 0.00 89.06 0.02

Size class not used for dietary risk quotients

Table X. Upper Bound Kenaga, Chronic Avian Dietary Based Risk Quotients

NOAEC (ppm) EECs and RQs

Short Grass Tall Grass Broadleaf

Plants Fruits/Pods/Seeds Arthropods

EEC RQ EEC RQ EEC RQ EEC RQ EEC RQ

520 227

.3 9 0.44 104.22 0.20 127.91 0.2

5 14.21 0.03 89.06 0.17

Size class not used for dietary risk quotients

Table X. Upper Bound Kenaga, Acute Mammalian Dose

- Based Risk Quotients

Size Class (grams) Adjus

ted

LD50 EECs and RQs

### 64 Short Grass Tall Grass Broadleaf

Plants Fruits/Pods/Seeds Arthropods

EEC RQ EEC RQ EEC RQ EEC RQ EEC RQ EEC

15 10989.

15 216.80 0.02 99.37 0.01 121.9

5 0.01 13.55 0.00 84.912 0.0077 3.011

35 8891.4

0 149.84 0.02 68.67 0.01 84.28 0.01 9.36 0.00 58.6856 0.0066 2.08

1000 3845.8

0 34.74 0.01 15.92 0.00 19.54 0.01 2.17 0.00 13.6065 0.0035 0.482

Table X. Upper Bound Kenaga, Chronic Mammalian Dietary Based Risk Quotients

NOAEC (ppm) EECs and RQs

Short Grass Tall Grass Broadleaf Plants Fruits/Pods/Seeds/Large

Insects Arthropods

EEC RQ EEC RQ EEC RQ EEC RQ EEC RQ

20000 227.

39 0.01 104.

22 0.01 127.91 0.01 14.21 0.00 89.06 0.00

Size class not used for dietary risk quotients

Table X. Upper Bound Kenaga, Chronic Mammalian Dose

- Based Risk Quotients

Size Class (grams) Adjusted

NOAEL EECs and RQs

Short Grass Tall Grass Broadleaf Plants Fruits/Pods/Seeds Arthropods

EEC RQ EEC RQ EEC RQ EEC RQ EEC RQ EEC

15 2197 .83 216.80 0.10 99.37 0.05 121.95 0.06 13.55 0.01 84.91 0.04 3.01

35 1778.28 149.84 0.08 68.67 0.04 84.28 0.05 9.36 0.01 58.69 0.03 2.08

1000 769.16 34.74 0.05 15.92 0.02 19.54 0.03 2.17 0.00 13.61 0.02 0.48

### 65 Upper Bound Kenaga, Acute Mammalian Dose

- Based Risk Quotients

Size

Class (gra ms) Adjus

ted

LD50 EECs and RQs

Short Grass Tall Grass Broadleaf Plants Fruits/Pods/Seeds Granivore

EEC RQ EEC RQ EEC RQ EEC RQ EEC RQ

15 1098

9.15 82.76 0.0

1 37.93 0.00 46.55 0.00 5.17 0.00 1.1495 0.0001

35 8891.

40 57.20 0.0

1 26.22 0.00 32.18 0.00 3.58 0.00 0.7945 9E

- 05

1000 3845.

80 13.26 0.0

0 6.08 0.00 7.46 0.00 0.83 0.00 0.1842 5E

- 05

Upper Bound Kenaga, Chronic Mammalian Dietary Based Risk Quotients

NOAEC (ppm) EECs and RQs

Short Grass Tall Grass Broadleaf

Plants Fruits/Pods/Seeds/Large Insects

EEC RQ EEC RQ EEC RQ EEC RQ

8000 86.81 0.01 39.7

9 0.00 48.83 0.01 5.43 0.00

Size class not used for dietary risk quotients

Upper Bound Kenaga, Chronic Mammalian Dose

- Based Risk Quotients

Size

Class (grams) Adjusted

NOAEL EECs and RQs

Short Grass Tall Grass Broadleaf Plants Fruits/Pods/

Seeds Granivore

EEC RQ EEC RQ EEC RQ EEC RQ EEC RQ

15 879.13 82.76 0.09 37.93 0.04 46.55 0.05 5.17 0.01 1.15 0.00

35 711.31 57.20 0.08 26.22 0.04 32.18 0.05 3.58 0.01 0.79 0.00

1000 307.66 13.26 0.04 6.08 0.02 7.46 0.02 0.83 0.00 0.18 0.00

### 66 Appendix E: Output of TerrPlant Model Results

TerrPlant v. 1.2.2 Green values signify user inputs (Tables 1, 2 and 4). Input and output guidance is in popups indicated by red arrows.

Table 1. Chemical Identity.

Chemical Name Methoxyfenozide

PC code 121027

Use Cotton
Application Method Aerial

Application Form Spray Solubility in Water (ppm) 3.3

Table 2. Input parameters used to derive EECs.

Input Parameter Symbol Value Units

Application Rate A 0.4 lb ai/A

Incorporation I 1 none
Runoff Fraction R 0.01 none

Drift Fraction D 0.05 none

Table 3. EECs for Methoxyfenozide. Units in lb ai/A.

Description Equation EEC

Runoff to dry areas (A/I)*R 0.004

Runoff to semi

- aquatic areas (A/I)*R*10 0.04 Spray drift A*D 0.02 Total for dry areas ((A/I)*R)+(A*D) 0.024

Total for semi

- aquatic areas ((A/I)*R*10)+(A*D) 0.06

Table 4. Plant survival and growth data used for RQ derivation. Units are in lb ai/A.

Seedling Emergence Vegetative Vigor
Plant type EC 25 NOAEC EC 25 NOAEC

Monocot 1.94 1.94 1.97 1.97

Dicot 1.94 0.98 1.97 0.97

Table 5. RQ values for plants in dry and semi

- aquatic areas exposed to Methoxyfenozide through runoff and/or spray drift.*

Plant Type Listed Status Dry Semi

- Aquatic Spray Drift

Monocot non

- listed <0.1 <0.1 <0.1

Monocot listed <0.1 <0.1 <0.1

Dicot non

- listed <0.1 <0.1 <0.1

Dicot listed <0.1 <0.1 <0.1

*If RQ > 1.0, the LOC is exceeded, resulting in potential for risk to that plant group.

### 67 Appendix F : Output Value of NC cotton scenario in the pond

Summary of Water Modeling of Methoxyfenozide and the USEPA Standard Pond Estimated Environmental Concentrations for Methoxyfenozide are presented in Table 1 for the USEPA standard pond with the NCcottonSTD field scenario. A graphical presentation of the year

- to

- year peaks is presented in Figure 1. These values were generated with the Surface Water Concentration Calculator (SWCC Version 1.106). Critical input

values for the model are summarized in Tables 2 and 3. This model estimates that about 4.9% of Methoxyfenozide applied to the field eventually reaches the water body. The main mechanism of transport from the field to the water body is by runoff (64.2% of the total transp ort), followed by spray drift (25.5%) and erosion (10.4%). In the water body, pesticide dissipates with an effective water column half

- life of 2684.7 days. (This value does not include dissipation by transport to the benthic region; it includes only proces ses that result in removal of pesticide from the complete system.) The main source of dissipation in the water column is metabolism (effective average half

life = 2765.8 days) followed by volatilization (91570.1 days). In the benthic region, pesticide diss ipation is negligible (3480.8 days). The main source of dissipation in the benthic region is metabolism (effective average half

- life = 3480.8 days). The vast majority of the pesticide in the benthic region (98.15%) is sorbed to sediment rather than in the pore water.

Table 1. Estimated Environmental Concentrations (ppb) for Methoxyfenozide.

Peak (1

- in

- 10 yr) 185.

4

- day Avg (1

- in

- 10 yr) 185.

21

- day Avg (1

- in

- 10 yr) 183.

60

- day Avg (1

- in

- 10 yr) 182.

365

- day Avg (1

- in

- 10 yr) 176.

Entire Simulation Mean 123.

Table 2. Summary of Model Inputs for Methoxyfenozide.

Scenario NCcottonSTD

Cropped Area Fraction 1

Koc (ml/g) 490

Water Half

- Life (days) @ 25 °C 1559

Benthic Half

- Life (days) @ 25 °C 1962

Photolysis Half

- Life (days) @ 40 °Lat 0

Hydrolysis Half

- Life (days) 0

Soil Half

- Life (days) @ 25 °C 960

Foliar Half

- Life (days) 0

Molecular Wt 368

Vapor Pressure (torr) 2e

- 8

Solubility (mg/l) 3.3

Table 3. Application Schedule for Methoxyfenozide.

### 68 Date (Mon/Day) Type Amount (kg/ha) Eff. Drift

7/18 Foliar 0.45 0.95 0.125

7/28 Foliar 0.45 0.95 0.125

8/7 Foliar 0.22 0.95 0.125

Figure 1. Yearly Peak Concentrations

### 69 Appendix G. Output of KABAM Model for Methoxyfenozide

Table G1. Estimated concentrations of Methoxyfenozide in ecosystem components.

Ecosystem Component Total
concentration

(μg/kg

- ww) Lipid

normalized
concentration

(μg/kg

- lipid) Contribution

due to diet (μg/kg

- ww) Contribution

due to respiration (μg/kg

- ww)
Water (total)* 178 N/A N/A N/A
Water (freely dissolved)* 178 N/A N/A N/A
Sediment (pore water)* 181 N/A N/A N/A
Sediment (in solid)** 3,548 N/A N/A N/A
Phytoplankton 43,774 2188680 N/A 43,773.60
Zooplankton 32,147 1071561 57.01 32,089.82

Benthic Invertebrates 35,172 1172402 148.48 35,023.59

Filter Feeders 23,180 1158985 95.86 23,083.85

Small Fish 45,566 1139159 613.60 44,952.77

Medium Fish 46,030 1150747 1,164.09 44,865.78
Large Fish 46,798 1169955 2,097.69 44,700.50
* Units: μg/L; **Units: μg/kg

- dw

0 5000 10000 15000 20000 25000 30000 35000 40000 45000 50000

Zooplankton Benthic

Invertebrates Filter Feeders Small Fish Medium Fish Large FishConcentration (μg/kg)

Trophic Level

Figure 1. Total pesticide concentration per trophic level Contribution due to respiration (μg/kg-ww)

Contribution due to diet (μg/kg-ww)

### 70 Table G2. Total BCFand BAF values of Methoxyfenozide in aquatic trophic levels.

Trophic Level Total BCF (μg/kg

ww)/(μg/L) Total BAF (μg/kg

ww)/(μg/L)
Phytoplankton 253 246
Zooplankton 180 181

Benthic Invertebrates 197 198

Filter Feeders 130 130

Small Fish 253 256

Medium Fish 253 259 Large Fish 253 263

Table G3. Lipid

- normalized BCF, BAF, BMF and BSAF values of Methoxyfenozide in aquatic trophic levels.

Trophic Level BCF (μg/kg

lipid)/(μg/L) BAF (μg/kg

lipid)/(μg/L) BMF (μg/kg

lipid)/(μg/kg

lipid) BSAF (μg/kg

lipid)/(μg/kg

OC)
Phytoplankton 12640 12296 N/A 25
Zooplankton 6011 6020 0.49 12

Benthic Invertebrates 6565 6587 1.09 13

Filter Feeders 6490 6511 1.08 13

Small Fish 6328 6400 1.02 13

Medium Fish 6328 6465 1.00 13 Large Fish 6322 6573 1.02 13

Table G4. Calculation of EECs for mammals and birds consuming fish contaminated by Methoxyfenozide.

Wildlife Species Biological Parameters EECs (pesticide intake) Body Weight

(kg) Dry Food Ingestion Rate (kg

- dry

food/kg

bw/day) Wet Food Ingestion Rate (kg

- wet

food/kg

bw/day) Drinking

Water

Intake (L/d) Dose Based (mg/kg

bw/d) Dietary

Based (ppm)

Mammalian

fog/water shrew 0.02 0.140 0.585 0.003 20.609 35.17

rice rat/star

- nosed

mole 0.1 0.107 0.484 0.011 16.785 34.64

small mink 0.5 0.079 0.293 0.048 13.520 46.03

large mink 1.8 0.062 0.229 0.168 10.565 46.03

### 71 small river otter 5.0 0.052 0.191 0.421 8.810 46.03

large river otter 15.0 0.042 0.157 1.133 7.367 46.80

Avian
sandpipers 0.0 0.228 1.034 0.004 35.9629 34.75

cranes 6.7 0.030 0.136 0.211 4.7493 34.91

rails 0.1 0.147 0.577 0.010 23.3327 40.37

herons 2.9 0.040 0.157 0.120 6.3980 40.60

small osprey 1.3 0.054 0.199 0.069 9.1884 46.03

white pelican 7.5 0.029 0.107 0.228 4.9987 46.80

Table G5. Calculation of toxicity values for mammals and birds consuming

fish contaminated by Methoxyfenozide.

Wildlife Species Toxicity Values

Acute Chronic

Dose

Based (mg/kg

bw) Dietary

Based (mg/kg

- diet) Dose Based (mg/kg

- bw) Dietary

Based (mg/kg

- diet)

Mammalian fog/water shrew 10499.51 N/A 2099.90 20000

rice rat/star

- nosed

mole 7122.50 N/A 1424.50 20000

small mink 4695.52 N/A 939.10 20000

large mink 3320.24 N/A 664.05 20000

small river otter 2571.84 N/A 514.37 20000

large river otter 1954.18 N/A 390.84 20000

Avian
sandpipers 1620.97 5870.00 N/A 520

cranes 3877.31 5870.00 N/A 520

rails 1956.07 5870.00 N/A 520

herons 3419.63 5870.00 N/A 520

### 72 small osprey 3014.09 5870.00 N/A 520

white pelican 3943.47 5870.00 N/A 520

Table G6. Calculation of RQ values for mammals and birds consuming fish contaminated by Methoxyfenozide.

Wildlife Species Acute Chronic

Dose

Based Dietary

Based Dose Based Dietary

Based

Mammalian
fog/water shrew 0.002 N/A 0.010 0.002

rice rat/star

- nosed

mole 0.002 N/A 0.012 0.002

small mink 0.003 N/A 0.014 0.002

large mink 0.003 N/A 0.016 0.002

small river otter 0.003 N/A 0.017 0.002

large river otter 0.004 N/A 0.019 0.002

Avian
sandpipers 0.022 0.006 N/A 0.067

cranes 0.001 0.006 N/A 0.067

rails 0.012 0.007 N/A 0.078

herons 0.002 0.007 N/A 0.078

small osprey 0.003 0.008 N/A 0.089

white pelican 0.001 0.008 N/A 0.090