Docket Number EPA

- HQ

- OPP

- 2010

- 0815

www.regulations.gov



## Carfentrazone

- ethyl

Summary Document Registration Review: Initial Docket

March 20113 TABLE OF CONTENTS

I. Preliminary Work Plan (PWP) 4

II. Fact Sheet 12

This Preliminary Work Plan and Fact Sheet summarize the Environmental Protection Agency’s current position based on the following documents:

1. Registration Review: Preliminary Problem Formulation for Environmental Fate, Ecological Risk, Enda ngered Species, and Drinking Water Exposure Assessments for Carfentrazone

- ethyl

, March 8 , 2011

.

2. Carfentrazone

- ethyl. Human Health Assessment Scoping Document in Support of Registration Review

, February 9, 2011

.

3. Carfentrazone

- ethyl : Review of Human Inc idents, November 30, 2 010

.

4. Carfentrazone

- ethyl Screening Level Usage Analysis (SLUA)

, July 21 , 2010

.

5. Carfentrazone

- ethyl California D epartment of P esticide R egulation Usage Data, May 26, 2010

6. Appendix A: Uses of Carfentrazone

- ethyl Considered in Registr ation Review Work Planning

, August 17, 2010

.

7. BEAD Chemical Profile for Registration Review: Carfentrazone

- ethyl , February 23, 2011

.

All supporting documents for the registration review of carfentrazone

- ethyl are located in docket EPA

- HQ

- OPP

- 2010

- 0815 at www.regulations.gov.4

I. PRELIMINARY WORK PLAN

Introduction

The Food Quality Protection Act (FQPA) of 1996 mandated a registration review program. All pesticides distributed or sold in the United States (U.S.) generally must be registered by the En vironmental Protection Agency (EPA or the Agency ), based on scientific data showing that they will not cause unreasonable risks to human health or the environment when used as directed on product labeling. The registration review program is intended to ma ke sure that, as the ability to assess risk evolves and as policies and practices change, all registered pesticides continue to meet the statutory standard of no unreasonable adverse effects to human health or the environment. Changes in science, public p olicy, and pesticide use practices will occur over time. Through the registration review program, the Agency periodically reevaluates pesticides to make sure that as change occurs, products in the marketplace can be used safely. Information on this
progr am is provided at: http://www.epa.gov/oppsrrd1/registration_review/

.
The Agency is implementing the registration review program pursuant to Section 3(g) of the Federal Insecticide, Fungic ide, and Rodenticide Act (FIFRA) , and will review each registered pesticide every 15 years to determine whether it continues to meet the FIFRA standard for registration. T he Agency will consider benefits information and data as required by FIFRA. The pub lic phase of registration review begins when the initial docket is opened for each case. The docket is the Agency’s opportunity to state what it knows about the pesticide and what additional risk analyses and data or information it believes are needed to make a registration review decision. After reviewing and responding to comments and data received in the docket during this initial comment period, the Agency will develop and commit to a final work plan and schedule for the registration review of carfent razone

- ethyl

.

Carfentrazone

- ethyl i s a post

- emergent herbicide registered for use to control broadleaf weeds. It is registered for use on a variety of agricultural crops, turf (including golf courses and residential lawns), aquatic areas (including water bodies and wetlands) , and industrial and utility sites. Carfentrazone

- ethyl is part of the class of herbicides referred to as Light Dependent Peroxidizing Herbicides (LDPH), which have enhanced toxicity in the presence of solar ultraviolet light. Carfen trazone

- ethyl was first register ed in the United States in 1998, and therefore it was not subject to the FIFRA reregistration program.

Anticipated Risk Assessment and Data Needs

The Agency anticipates requiring data considered necessary to conduct a com prehensive ecological risk assessment

, including an end angered species risk assessment

, and to update the human health risk assessment for all uses of carfentrazone

- ethyl

. Below is a summary of the issues relevant to the registration review of carfentrazo ne

- ethyl and the data the Agency anticipates requiring

.5

Ecological Risk: The most r ecent ecological risk assessment for carfentrazone

- ethyl was conducted in 200 4 in support of new uses on grapes, tobacco, citrus, pome and stone fruits, and tree
nuts.

S ince carfentrazone

- ethyl products are registered for direct applications to water , the Agency anticipates requiring additional data to assess potential risk to aquatic organisms. The Agency anticipates requiring data on the degradate carfentrazone acid, w hich is expected to be dominant in water after application of carfentrazone

- ethyl.

Given that carfentrazone

- ethyl is an herbicide, and incident reports confirm adverse effects to non

- target plants, the Agency anticipates requiring additional data to asses s potential risk to terrestrial plants. Toxicity data using a typical end

- use product is anticipated to be required to evaluate risk to plants.

Toxicity data are not available for passerine bird species that may

, in some cases

, be more sensitive tha n the waterfowl and upland game birds that were tested in previous carfentrazone

- ethyl studies. The Agency anticipates requiring passerine data.

LDPH registrants are in the process of conducting a modified freshwater fish early life stage study to quantitativ ely determine the increase in toxicity of this class of herbicides in the presence of direct sunlight. The Agency expects to receive these data in the summer of 2011 in response to the Data Call

- in (DCI) for this study . These data will be used in the reg istration review ecological risk assessment for carfentrazone

- ethyl.

The Agency has not conducted an ecological risk assessment that supports a complete endangered species determination for carfentrazone

- ethyl

. The ecological risk assessment planned duri ng registration review will allow the Agency to determine whether carfentrazone

- ethyl ’s use has “no effect” or “may affect” federally listed threatened or endangered species (listed species) or their designated critical habitats. When an assessment conclu des that a pesticide’s use “may affect” a listed species or its designated critical habitat, th e Agency will consult with the U.S. Fish and Wildlife Service ( FWS ) and/or National Marine Fisheries Service (NMFS) (the Services), as appropriate.

The Agency a nticipates requiring the following data in order to conduct a complete ecological risk assessment , including an endangered species assessment

, for carfentrazone

- ethyl :

Environmental fate

o G uideline No. 835. 2240

– Photodegradation in water ( carfentrazone a cid )

o Guideline No. 835.4400

– Anaerobic aquatic metabolism6

o Guideline No. 835.6100

– Terrestrial field dissipation (only an independent laboratory validation (ILV) of the submitted analytical method would likely be required to satisfy this guideline)

o Guidel ine No. 835.6200

– Aquatic ) field dissipation (only frozen storage stability data would likely be required to satisfy this guideline)

Ecologica l toxicity

o Guideline No. 850.1025

– Invertebrates acute toxicity

– mollusk (saltwater) (carfentrazone acid)

o G uideline No. 850.1075

– Fish acute toxicity (saltwater) (carfentrazone acid)

o Guideline No. 850.1300

– Aquatic invertebrate life

- cycle (freshwater) (carfentrazone acid)

o Guideline No. 850.1350

– Aquatic invertebrate life

- cycle (saltwater) (carfentrazone acid )

o Guideline No. 850.1400

– F ish early life stage ( saltwater) (carfentrazone acid)

o Guideline No. 850.1500

– F ish life

- cycle (freshwater) (carfentrazone acid)

o Guideline No. 850.1735

– Whole sediment : acute freshwater invertebrate s

o Guideline No. 850.1740

– Wh ole sediment : acute m arine invertebrate s

o Guideline No. 850.2100

– Avian acute oral toxicity (passerine species)

o G uideline No. 850.4100

- Seeding Emergence (Tier II)

o G uideline No. 850.4150

- Vegetative Vigor (Tier II)

Please refer to the March 8, 2011 “ Re gistration Review: Preliminary Problem Formulation for Environmental Fate, Ecological Risk, Endangered Species, and Drinking Water Exposure Assessments for Carfentrazone

- ethyl

, ” for a more detailed discussion of the anticipated ecological risk assessment a nd data needs.

Human Health Risk: The most recent human health risk assessment was conducted in 2006 in support of use on cereal grain, peanut, soybean, and sugarcane as a harvest

- aid

.
The Agency anticipates conducting a drinking water assessment in regi stration review. Results of the updated drinking water assessment may necessitate a revised dietary exposure assessment.

The Agency anticipates conducting new occupational exposure assessments in registration review. Several occupational handler scenari os need to be assessed, which have not been assessed previously, or need to be reassessed based on higher application rates or area treated.

A revised residential exposure assessment may need to be performed to include residential handler scenarios and up dated residential post

- application scenarios (higher7

turf/home lawn application rate)

. This may necessitate a new aggregate exposure
assessment.

If new policies or procedures are put into place, the Agency may revisit the need for a quantitative post

- app lication inhalation exposure assessment for carfentrazone

- ethyl

.
The analytical tolerance enforcement method for livestock, fish, and shellfish was considered acceptable pending validation from EPA’s Analytical Chemistry Laboratory. However, the validati on procedure has changed, and now laboratory validation is not required. As part of registration review, the Agency may evaluate the suitability of the existing analytical tolerance enforcement method for livestock, fish, and shellfish according to new pr ocedures. If the method is found to be unsuitable for tolerance enforcement, then the technical registrant would need to propose and validate a new method.

As part of registration review, the Agency anticipates making the following tolerance changes:

o T he banana tolerance may be lowered to 0.10 ppm

. o The following currently

- established tolerances may be deleted: cotton hulls, cotton meal, cotton oil , barley flour, barley bran, millet flour, oat flour, rye flour, rye bran, wheat bran, wheat flour, wheat mid dlings, wheat shorts, wheat germ, and caneberry subgroup 13A.

o T he cereal grain forage, hay, stover, and straw tolerances may be altered as there are conflicting commodity definitions and/or tolerance levels

. o T he tolerance expression may be updated as f ollows to conform to current standards: Tolerances are established for residues of carfentrazone

- ethyl, including its metabolites and degradates, in or on the commodities listed below. Compliance with the following tolerance levels is to be determined by measuring carfentrazone

- ethyl ( ethyl alpha

- 2

- dichloro

- 5

- [4

- (difluoromethyl)

- 4,5

- dihydro

- 3

- methyl

- 5

- oxo

- 1 H

- 1,2,4

- triazol

- 1

- yl]

- 4

- fluorobenzenepropanoate) and its metabolite carfentrazone

chloropropionic acid (alpha, 2

- dichloro

- 5

- [4

- difluoromethyl)

- 4,5

- dihy dro

- 3

- methyl

5

- oxo

- 1 H

- 1,2,4

- triazol

- 1

- yl]

- 4

- fluorobenzenepropanoic acid).

The Agency anticipates requiring the following data in order to conduct a complete human health risk assessment for carfentrazone

- ethyl :

A 28

- day inhalation toxicity study was pr eviously waived for carfentrazone

- ethyl. However, the Agency is re

- evaluating its inhalation waiver criteria, so this study may be required for registration review.8

o Guideline No. 870.3465

– 90 1

- day inhalation

- rat

o Guideline No. 870.7800

– Immunotoxicit y

In addition, the Agency anticipates requiring the following residue chemistry data to complete the residue chemistry database for carfentrazone

- ethyl.

o Guideline No. 860.1500 Crop Field Trials

– soybeans In lieu of conducting this study the registrant m ay revise label language to include a restriction prohibiting the feeding of soybean forage and hay to livestock.

o Guideline No. 860.1500 Crop Field Trials

- cranberry In lieu of conducting this study the registrant may remove instructions for application to cranberry from all labels.

o Guideline No. 860.1500 Crop Field Trials

– dry peas, vegetable legume (Group 6), and vegetable foliage of legume (group 7) In lieu of conducting these studies the registrant may revise label language to restrict harvest

- aid application to only the following crops: cereal grains, soybean, cotton, peanut, sugarcane, and potato.

o Guideline No. 860.1900 Field Rotational Crops In lieu of conducting this study the registrant may revise label language that indicate the following r otational crop restrictions: seasonal application rate of <0.031 lb ai/acre

- rotate to a registered crop at anytime and to all other crops 12 months after application; seasonal application rate of >0.031 lb ai/acre

- rotate to only a registered crop.

Pr ovided these changes are made, the residue chemistry database will be adequate to support carfentrazone

- ethyl registrations.

Please refer to the January 19, 2011 “ Carfentrazone

- ethyl. Human Health Assessment Scoping Document in Support of Registration Re view, ” available in the docket, for a detailed discussion of the anticipated human health risk assessment and data needs.

Endocrine Disruptor Screening Program

As required by FIFRA and FFDCA, EPA reviews numerous studies to assess potential adverse
outco mes 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 endpo ints 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 ecologica l hazard assessments, EPA evaluates acute tests and

1 A 28

- day study may be sufficient to satisfy guideline requirement.9

chronic studies that assess growth, developmental and reproductive effects in different taxonomic groups. As part of its most recent registration decision , EPA reviewed these data and selected the most s ensitive endpoints for relevant risk assessment scenarios from the existing hazard database. However, as required by FFDCA section 408(p), carfentrazone

- ethyl 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 effec ts as the Administrator may designate.” The EDSP employs a two

- tiered approach to making the statutorily required determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a chemical substance to interact with the es trogen, androgen, or thyroid (E, A, or T) hormonal systems. Chemicals that go through Tier 1 screening and are found to have the potential to interact with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA will determine whi ch, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 testing is designed to identify any adverse endocrine

- 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, EPA issued test orders/data call

- ins for the first group of 67 chemicals, which contains 58 pesticide active ingredients and 9 in ert ingredients. Carfentrazone

ethyl is not among the group of 58 pesticide active ingredients on the initial list to be screened under the EDSP. Accordingly, as part of registration review, EPA will issue future EDSP orders/data call

- ins, requiring the submission of EDSP screening assays for carfentrazone

- ethyl

. For further information on the status of the EDSP, the policies and procedures, the list of 67 chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our web site: http://www.epa.gov/endo/

.

Timeline

The Agency has created the following estimated timeline for the completion of the registration review for carfentrazone

- ethyl.

Registration Review for Carfentrazone

- ethyl

– Projected Registration Review Timeline
Activities Estimated Date Opening the docket Open Docket and Public Comment Period 201 1

– March Close Public Comment 201 1

– May Case Development Final Work Plan 2011

– August Issue DCI 201 2

– Apr.

- Jun e Data Submission 201 4

– Apr.

- June Open Public Comment Period for Preliminary Risk Assessments 201 5

– Oct.

- Dec

.10

Close Public Comment Period 2016

– Jan

. - March Registration Review Decision Open Public Comment Period for Proposed Registration Revi ew Decision 2016

– Apr.

- June

Close Public Comment Period 2016

– July

– Sept. Registration Review Decision and Begin Post

- Decision Follow

- up 201 7 Total (years) 6

Guidance for Commenters

The public is invited to comment on EPA’s preliminary work pl an and rationale s . The Agency will carefully consider all comments, as well as any additional information or data provided in a timely manner, prior to issuing a final work plan for the carfentrazone

- ethyl case.

Trade Irritants

Through the registration review process, the Agency intends to solicit information on trade irritants and, to the extent feasible, take steps toward facilitating irritant resolution. Growers and other stakeholders are asked to comment on any trade irritant issues resulting from l ack of Maximum Residue Limits (MRLs) or disparities between U.S. tolerances and MRLs in key export markets, providing as much specificity as possible regarding the nature of the concern.

Environmental Justice

EPA seeks to achieve environmental justice, t he fair treatment and meaningful involvement of all people, regardless of race, color, national origin, or income, in the development, implementation, and enforcement of environmental laws, regulations, and policies. To help address potential environmenta l justice issues, the Agency seeks information on any groups or segments of the population who, as a result of their location, cultural practices, or other factors, may have atypical, unusually high exposure to carfentrazone

- ethyl compared to the general p opulation. Please comment if you are aware of any sub

- populations that may have atypical, unusually high exposure, compared to the general population.

Water Quality

Carfentrazone

- ethyl is not identified as a cause of impairment for any water bodies list ed as impaired under section 303(d) of the Clean Water Act 2

. In addition, n o Total Maximum Daily Load s (TMDL) have been developed for carfentrazone

- ethyl 3 . More information on impaired water bodies and TMDLs can be found at the Agency’s website 4

. The Age ncy invites submission of water quality data for th is pesticide. To the extent possible, data should conform to the quality

2 http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885

3 http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id=885&p_pollutant_group_name=PEST ICIDES

4 http://www.epa.gov/owow/tmdl/11

standards in Appendix A of the OPP Standard Operating Procedure: Inclusion of Impaired Water Body and Other Water Quality Data in O PP’s Registration Review Risk Assessment and Management Process 5 in order to ensure they can be used quantitatively or qualitatively in pesticide risk assessments.

Other Information

Stakeholders are also specifically asked to provide information and data that will assist the Agency in refining risk assessments, including any species

- specific ecological effects determinations for carfentrazone

- ethyl . The Agency is interested in receiving the following information:

1. Confirmation on the following label info rmation.

a. sites of application b. formulations

c. application methods and equipment d. maximum application rates

e. frequency of application, application intervals, and maximum number of applications per season and per year f. geographic limitations on use 2. Use or potentia l use distribution ( e.g . geographical distribution of relevant uses). 3. Use history. 4. Median and 90 th percentile reported use rates (lb/A, lb 1K sq.ft) from usage data

– national, state and county. 5. Application timing (date of first application and application intervals) by use

– national, state, and county. 6. Usage/use information for non

- agricultural uses. 7. Directly acquired county

- level usage data (not derived from state level data).

a. maximum reported use rate (lb/cc) from usage data

– county b. median and 90 th pe rcentile number of applications

– county

c. total pounds per year

– county d. the year the pesticide was last used in the county/sub

- county area

e. the years in which the pesticide was applied in the county/sub

- county area 8. Typical application interval (days). 9. State or local use restrictions. 10. Ecological inciden ts (non

- target plant damage and avian, fish, reptilian, amphibian, mammalian mortalities, and bee or beneficial insect mortalities) not already reported to the Agency. 11. Information on decline in usage, such as o n cotton and rice.

5 http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm12

Next Steps

After the 6 0

- day comment period closes, the Agency will consider and respond to any comments

re ceive d in a timely manner . The Agency expects to issue a Final Work Plan in August o f 2011 for carfentrazone

- ethyl.

II. FACT SHEE T

Background Information Carfentrazone

- ethyl case number: 7422 Carfentrazone

- ethyl PC Code : 128712 ; CAS # 128639

- 02

- 1 Carfentrazone

- ethyl was first registered in 1998 and therefore it was not subject to the FIFRA reregistration program

. T echnical registra nt : FMC Corp. Agricultural Products Group Active registrations a s of January 201 1 :

o 46 Section 3 registrations

o 10 Section 24(c) registrations ( Special Local Need ) Pesticide Re

- evaluation Division Contact : Jose Gayoso ( gayoso.jose @e pa.gov) Registration Division C ontact: Kathryn Montague ( montague

. kathryn @epa.gov )

Use and Usage Information For additional details, please refer to “ Carfentrazone

- ethyl Screening Level Usage Analysis (SLUA)

, “ July 21, 2010

, “ Appendix A: Uses of Carfentr azone

- ethyl Considered in Registration Review Work Planning, ” August 17, 2010

, “ Carfentrazone

- ethyl California Department of Pesticide Regulation Usage Data, ” May 26, 2010, and “ BEAD Chemical Profile for Registration Review: Carfentrazone

- ethyl, ” February 23, 2011

, ” which are available in the carfentrazone

ethyl docket.

In agriculture, carfentrazone

- ethyl is an herbicide used mainly in cotton as a harvest aid/defoliant and as an at

- planting or pre

- plant burndown to control many broadleaf weeds in corn, soy bean, rice, and small grain crops. The primary use of carfentrazone

- ethyl is in commercial turf grass maintenance and production. Carfentrazone

- ethyl is also registered for use in aquatic and non

- agricultural/industrial sites. Weeds controlled by carfe ntrazone

- ethyl include many species and biotypes that are resistant to several classes of herbicides. Carfentrazone

- ethyl is formulated as water dispersible granules, emulsifiable concentrate, and soluble concentrate, ready

- to

- use solution and also as wate r

- soluble packaging. Types of application include broadcast, spot treatment, water treatment (surface), water treatment (subsurface), and directed spray. Equipment used includes various types of sprayers (backpack, boom, compression, tank

- type etc.)

, aircr afts

, and boats.13

According to the Agency’s Screening Level Usage Analysis (SLUA), based on data from 2001

- 2008, c arfentrazone

- ethyl agricultural usage is highest on cotton and rice, with annual average s of 20,000 lbs and 10,000 lbs of active ingredient (l bs a.i.) applied

, respectively. The crop with the highest max percent crop treated with carfentrazone

ethyl is caneberries (65%), followed by hops (60%). Based on private market pesticide usage data from 1998

- 2008 , the annual total agricultural usage aver aged approximately 32,000 lbs a.i. for almost 2 million acres. The largest markets in terms of total pounds of active ingredient applied are cotton ( 36 %)

, rice (24%), and corn (13%). The highest acreage crops treated are cotton (37%), corn (24%), and ric e (10%)

. The states with the most agricultural usage in terms of pounds carfentrazone

- ethyl applied are California (20%), Arkansas (13%), and Texas (11%).
Non

- agricultural usage data are limited. Based on private market pesticide usage data from 2002

- 200 6, golf course and lawn care usage has increased.

Recent and Pending Actions There are no recent or pending action s for carfentrazone

- ethyl

.
Ecological Risk Assessment Status The following are key findings from the most recent ecological risk assessment s regarding the environmental fate, ecological effects and risks of carfentrazone

- ethyl

. F or a detailed discussion

, p lease refer to the March 8, 2011 “ Registration Review: Preliminary Problem Formulation for Environmental Fate, Ecological Risk, Endangered Species, and Drinking Water Exposure Assessments for Carfentrazone

- ethyl

, ” located in the docket.

Previous ecological risk assessments identified risk s of concern for aquatic and terrestrial plants from many uses, especially aerial application to corn an d sorghum and use in rice paddies ; acute and chronic risk s to fish, aquatic plants and shoreline terrestrial plants from use as an aquatic herbicide ; and chronic risk to fish from use on caneberries.

Available carfentrazone

- ethyl degradate toxicity data s uggest that degrad ates are less toxic to aquatic organisms than the parent

.

Human Health Risk Assessment Status T he following are key findings from the human health risk assessments conducted for carfentrazone

- ethyl registered uses. Please refer to the F ebruary 9, 2011 “ Carfentrazone

- ethyl. Human Health Assessment Scoping Document in Support of Registration Review, ” located in the docket

, for a detailed discussion of the human health risk assessment status.

Human Studies:
Past carfentrazone

- ethyl risk a ssessments rely in part on data from studies in which adult human subjects were intentionally exposed to a pesticide to determine their dermal and inhalation exposure. Many such studies, involving exposure to many different pesticides, comprise generic pe sticide exposure databases such as the Outdoor Residential Exposure14

Task Force (ORETF) Database

. EPA has reviewed all the studies supporting these multi

pesticide generic exposure databases, and has found no clear and convincing evidence that the conduct of any of them was either fundamentally unethical or significantly deficient relative to the ethical standards prevailing at the time the research was conducted. A ll applicable requirements of EPA’s Rule for the Protection of Human Subjects of Research (40 CFR Part 26) have been satisfied , and t here is no regulatory barrier to continued reliance on these studies.

Hazard Characterization : Carfentrazone

- e thyl acts as an inhibitor of protoporphyrinogen oxidase , which in mammals interferes with the heme biosyn thetic pathway and results in increased porphyrin levels.

Carfentrazone

- e thyl has low acute oral, dermal, and inhala tion toxicity (Toxicity Categories III and IV ). It is minimally irritating to the eyes, non

- irritating to the skin, and is not a skin sens itizer.

The mutagenic test battery demonstrated that carfentrazone

- ethyl is not mutagenic. In carcinogenicity studies in mice and rats, there was no indication of increased incidence of neoplasms and spontaneous tumor formation at the doses tested.

Di et ary Risk : In the most recent dietary risk assessment for carfentrazone

- ethyl, children 1

- 2 years old were identified as the most highly exposed subgroup with an aPAD of ≤ 1% ;) a nd a cPAD of 89 % . Therefore, acute and chronic exposure estimates did not exceed the Agency ’s level of concern.

Residential Risk: In the most recent carfentrazone

- ethyl human health risk assessment, the product label used for review only allow ed for application by professional lawn care operators to reside ntial lawns and to golf courses; t herefore, exposure to homeowners was not expected.

In the most recent carfentrazone

- ethyl human health risk assessment , a residential post

application expo sure assessment was conducted that assessed incidental oral exposure to children from the home lawn use, as well as inhalation and ingestion exposure to adult and child swimmers from the aquatic use. All residential incidental oral exposure and risk estim ates for the home lawn use wer e below the Agency’s level of concern at an application rate of 0.031 lb ai/A

. All incidental oral and inhalation exposure and risk estimates for the aquatic uses were below the Agency’s level of concern at an application

rat e of 0.2 lb ai/A.15

Aggregate Risk: In the most recent carfentrazone

- ethyl human health risk assessment , a cute and chronic aggregate risks are made up only of dietary sources; therefore, the exposure estimates provided in the dietary exposure analysis repr esent acute and chronic aggregate exposures, respectively, and are not of concern to the Agency . Short

- term aggregate exposures to carfentrazone

- ethyl were not of concern to Agency.

Occupational Risk : In t he most recent occupational handler exposure asse ssment, the Agency concluded that,
p rovided commercial pesticide handlers used label

- prescribed personal protective equipment (i.e., long pants, long

- sleeved shirt, shoes + socks and protective gloves), exposures to carfentrazone

- ethyl were not of concern to Agency

An appropriate endpoint attributable to exposure through the dermal route for carfentrazone

- ethyl was not identified. Therefore, dermal post

- application exposure assessments have not been performed for carfentrazone

- ethyl.

Incident s

Ecologi cal: An incident review was made on October 27, 2010 by querying the Ecological Incident Information System (EIIS, version 2.1) and the Avian Monitoring Information System (AIMS). Ten incidents involving carfentrazone

- ethyl have been reported. All report ed incidents involved plant damage; no animal incidents have been reported. The two incidents (I014796

- 001 and I014796

- 002) from registered use of carfentrazone

- ethyl were both from use on sweet corn in 2003, and involved extensive damage (145 and 515

acr es, respectively); however, both were determined “not likely” to have been caused by carfentrazone

- ethyl. Two incidents classified as “highly probable” for attribution to carfentrazone

- ethyl were both due to misuses, one intentional. Of the two incident s classified “probable,” one was deemed accidental (I020725

- 055), but one was undetermined (I019519

- 043), and therefore, may have been due to a registered use. Of the three incidents classified as “possible

, ” two were determined to be from misuse (one

acc idental) of carfentrazone

- ethyl, while the legality of use for the other was undetermined, and therefore, may have been due to a registered use.

Human Health: The OPP Incident Data System (IDS) was utilized for poisoning incident data on the active ingr edient carfentrazone

- ethyl. IDS records incidents of generally high severity in more detail, in software called the main IDS . This system stores incident data for death, major and moderate incidents, and it includes more details about the location, date and nature of the incident. The less

- severe human incidents are reported by registrants as counts, which are called aggregate summaries and are recorded in separate software. For IDS aggregate summaries, from January 1, 200 2 to May 27, 2010

, there are 37 case s16

reported for carfentrazone

- ethyl . Because it falls within the categories reported as counts (which includes minor, unknown, or no effects) , there is no unique report that provides details about the incident

, and single

- chemical incidents are not di stinguished from multiple

- chemical incidents. For the main IDS, from January 1, 200 2 to October 7, 2010, there is one case reported for single

- chemical carfentrazone

- ethyl only in the database. For this incident, the symptoms were unknown or not specifie d

.
Based on the low frequency and severity of incident cases, there does not appear to be a concern at this time that would warrant further investigation. The Agency will continue to monitor the incident information and if a concern is triggered, additio nal analysis will be included in the risk assessment.

Tolerances and International Harmonization

U.S. permanent tolerances and Canadian, Mexican, and Codex maximum residue limits (MRLs) are summarized in the February 9, 2011 “ Carfentrazone

- ethyl. Human Health Assessment Scoping Document in Support of Registration Review

. ” The U.S. and Canadian carfentrazone

ethyl residue definitions are harmonized and the numerical values are also harmonized for milk (0.05 ppm) and sorghum grain (0.25 ppm). For the rem aining commodities for which both the U.S. and Canada have tolerances/ MRLs, the U.S. tolerance is expressed with two significant figures (0.10 ppm or 0.80 ppm), while the Canadian MRL is expressed with one significant figure (0.1 or 0.8 ppm). It is noted that Mexico adopts U.S. tolerances and/or Codex MRLs for its export purposes. Since there are no carfentrazone

- ethyl Codex MRLs, EPA is working to harmonize the U.S. tolerances and Mexican MRLs.

Data Call

- I ns

In response to DCIs issued to them, LDPH te chnical registrants are in the process of conducting a modified freshwater fish early life stage study to quantitatively determine the increase in toxicity of this class of herbicides in the presence of direct sunlight. While carfentrazone

- ethyl is
not on e of the test substances in the study, the Agency has agreed that three LDPHs selected for the study may serve as surrogates for the remaining currently registered LDPHs , including carfentrazone

- ethyl . The Agency expects to receive these data in the summ er of 2011. These data will be used in the registration review ecological risk assessment for carfentrazone

- ethyl.

L abels

Active Section 3 l abels for carfentrazone

- ethyl can be obtained from the Pesticide Product Label System (PPLS) website: http://oaspub.epa.gov/pestlabl/ppls.home

.