Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov



# Quinclorac Summary Document Registration Review: Initial Docket

December 2007

Case # 7222Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

2 

# Quinclorac Summary Document Registration Review: Initial Docket

December 2007

Approved By:

___________________ Steven Bradbury, Ph.D. Director, Special Review and Reregistration DivisionDocket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

3 TABLE OF CONTENTS

Page #

I. Preliminary Work Plan (PWP) 4

II. Fact Sheet 9

III. Glossary of Terms and Abbreviations 14

IV. Ecological Risk Assessment Problem Formulation 16

V. Human Health Effects Scoping Document 56Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

4 I. Preliminary Work Plan - Quinclorac

Introduction: The Food Quality Protection Act of 1996 mandate d a new program: registration review. All pesticides distributed or sold in the United St ates generally must be registered by the U.S. Environmental Protection Agency (USEPA; EPA; The Agency), based on scientific data showing that they will not cause unreasonabl e risks to human health, workers, or the environment when used as directed on product la beling. The new registration review program is intended to make 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. Changes in science, public po licy, and pesticide use pr actices will occur over time. Through the new registration review pr ogram, the Agency periodically reevaluates pesticides to make sure that as change occurs, products in the marketplace can be used safely. Information on this program is provided at: h ttp://www.epa.gov/oppsrrd1/registration_review/.

The Agency has begun to implement the new registration review program, and will review each registered pesticide every 15 years to determine wh ether it continues to meet the FIFRA standard for registration. The public phase of registration review begins wh en the initial docket is opened for each case. The docket is the Agency’s opport unity 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. Af ter reviewing and responding to co mments and data received in the docket during this initial comment period, th e Agency will develop and commit to a final work plan and schedule for the re gistration review of quinclorac.

Quinclorac is a systemic pre- and post- emergent herbicide to control broa dleaf and grass weeds. It is registered for use on agricultural crops as well as on turf in residential and commercial areas.

Anticipated Risk Assessment and Data Needs: The Agency will conduct a comprehensive ecologi cal risk assessment, including an endangered species assessment for quinclorac. The Agency will also perform an occupational risk assessment, a drinking water assessment, a resi dential handler assessment, and an aggregate

assessment.

Ecological Risk:

• The most recent comprehensive ecological risk assessment for registered uses was conducted on wheat and sorghum in 1999. The Agency has not conducted a risk assessment that supports a complete endangere d species determination. Please refer to Section IV, Ecological Risk Assessment Probl em Formulation, for a detailed discussion of the anticipated risk assessment needs.Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

5 • The Agency anticipates needing the followi ng data in order to conduct a complete ecological risk assessment, including an e ndangered species assessment, for all uses:

o (GLN 850.1010) Aquatic invertebrate acute toxicity test, freshwater daphnids

o (GLN 850.1300) Daphnid chronic toxicity test

o (GLN 835.7100) Ground water monitoring

• The planned ecological risk assessment w ill allow the Agency to determine if quinclorac’s use has "no effect" on federally listed threatened or endangered species (listed species) or their designated critical habitat. If the screening level assessment indicates that quinclorac "may affect" a listed sp ecies or its designated critical habitat, the assessment will be refined. The refined assessment will allow the Agency to determine whether use of quinclorac is “likely to adversel y affect” the species or critical habitat or "not likely to adversely affect" the species or critical habitat. When an assessment concludes that a pesticide's use "may affect" a listed species or its designated critical habitat, the Agency will consult with the U. S. Fish and Wildlife Service and/or National Marine Fisheries Service (Services), as appropriate.

Human Health Risk:

• The toxicological endpoint sel ections are adequate; however, the toxicology database for quinclorac is incomplete at this time. A 90-day inhalation toxicity study in the rat is required to assess inhalation exposure from spray uses (GLN 870.3465).

• The residue chemistry database is complete. However, newly submitted aspirated grain fraction studies on wheat and sorghum will have to be reviewed, and livestock tolerances may need to be revised based on this review.

• The dietary (food alone) assessment is ade quate. However, a new drinking water assessment will be conducted; therefore, an aggregate assessment will be needed.

• The residential post application exposure asse ssment is adequate, th erefore no residential post application assessment is needed. However, no residential handler risks were assessed; therefore, a new residential handler assessment is needed.

• No occupational risk assessments have been conducted. Occupational risk assessments

will be needed for all scenarios.

• Please refer to Section V of this document, Human Health Effects Scoping Document, for

a detailed discussion of the anticipated risk assessment needs for human health.Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

6 Timeline: EPA has created the following estimated ti meline for the completion of the quinclorac registration review. The Agency may conduct th e occupational assessment much earlier in the process, allowing mitigation (if necessary) to occur well before completion of the final decision.

Registration Review for quinclorac – Projected Registration Review Timeline

Activities Estimated

Month/Year Phase 1: Opening the docket
Open Public Comment Period for Quinclorac Docket 2007 – Dec.

Close Public Comment Period 2008 – Mar.
Phase 2: Case Development
Develop Final Work Plan (FWP) 2008 – Apr.- Jun.

Issue DCI 2009 – Jan - Mar.

Data Submission 2013 – Jan - Mar.
Open Public Comment Period for Preliminary Risk Assessments 2014 – Jul. – Sept.

Close Public Comment Period 2014 - Oct. – Dec.

Phase 3: Registration Review Decision
Open Public Comment Period for Proposed Reg. Review Decision 2015 – Jan. – Mar.
Close Public Comment Period 2015 – Apr. – Jun. Final Decision and Begin Post-D ecision Follow-up 2015 – Jul. Sept. Total (years) 8

Guidance for Commenters: The public is invited to comment on EPA’s prel iminary registration review work plan and rationale. The Agency will carefully consid er all comments as well as any additional information or data provided prior to issuing a final work plan for the quinclorac case.

• Through the registration review process, th e 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 lack of Maximum Residue Li mits (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. Please see section V of this document, Quinclorac,

Human Risk Problem Formulation Document in Support of Registration Review, for a listing of the differences among the U.S., Canada, Codex, and Mexico tolerances.Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

7 • Quinclorac is not identified as a cause of impairment for any water bodies listed as impaired under section 303(d) of the Clean Water Act, based on information provided at http://oaspub.epa.gov/tmdl/wat ers_list.impairments?p_impid=3. The Agency invites submission of water quality data for this pesticide. To the extent possible, data should conform to the quality standards in A ppendix A of the “OPP Standard Operating Procedure: Inclusion of Impaired Water B ody and Other Water Quality Data in OPP’s Registration Review Risk Assessment and Management Process” (see: http://www.epa.gov/oppfead1/cb/ppdc/2006/novem ber06/session1-sop.pdf), in order to ensure they can be used quant itatively or qualitatively in pesticide risk assessments.

• EPA seeks to achieve environmental justi ce, the fair treatment and meaningful involvement of all people, regardless of r ace, color, national origin, or income, in the development, implementation, and enforcement of environmental laws, regulations, and policies. To help addre ss potential environmental justice issues, the Agency seeks information on any groups or segments of the population who, as a result of their location, cultural practi ces, or other factors, may have atypical, unusually high exposure to quinclorac compared to the general population. Please comment if you are aware of any s ub-populations that may have atypical, unusually high exposure compared to the general population.

Stakeholders are also specifically asked to prov ide information and data in the following areas.

• There is specific information that will assist the Agency in refining the ecological risk assessment, including any species-specific effects determinations. The Agency is interested in obtaining the following inform ation regarding the use of quinclorac:

1. confirmation on the following label information

a. sites of application

b. formulations

c. application methods and equipment

d. maximum application rates

e. frequency of application, applicati on intervals, and maximum number of applications per season

f. geographic limitations on use

2. use or potential use distribution (e.g., acreage and geographical distribution of relevant crops)

3. use history

4. median and 90 th percentile reported use rates (l bs ai/acre) from usage data – national, state, and county

5. application timing (date of first applica tion and application intervals) by crop – national, state, and county

6. sub-county crop location dataDocket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

8 7. usage/use information for non-agricultural uses (e.g., forestry, residential, rights-ofway)

8. directly acquired county-level usage da ta (not derived from state level data)

a. maximum reported use rate (lbs a i/acre) from usage data – county

b. percent crop treated – county

c. median and 90 th percentile number of applications – county

d. total pounds per year – county

e. the year the pesticide was last us ed in the county/sub-county area

f. the years in which the pesticide was applied in the county/sub-county area

9. typical interval (days)

10. state or local use restrictions

11. ecological incidents (non-target plant dama ge and avian, fish, reptilian, amphibian and mammalian mortalities) not already reported to the Agency

12. monitoring data

Next Steps: After the comment period closes, the Agency will prepare a Final Work Plan for this pesticide.Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

9 II. FACT SHEET

Background Information :

• Quinclorac Registration Review case number: 7222

• Quinclorac is a systemic pre- and post- emer gent herbicide to cont rol broadleaf and grass weeds on rice, sorghum, wheat, residential la wns, ornamentals and turf grass.

• Quinclorac PC code: 128974; CAS #: 84087-01-4

• Technical Registrant: Albaugh Inc.

• First approved for use in 1992, theref ore not subject to reregistration.

• Tolerance Reassessment was released on March 26, 1999 through publication in the Federal Register (64 FR 14626).

• Special Review and Reregistration Division (SRRD), Chemical Review Manager (CRM): Joy Schnackenbeck: schnackenbeck.joy@epa.gov

• Registration Division (RD) Contacts: Jim Tompkins: tompkins.jim@epa.gov; Hope Johnson: johnson.hope@epa.gov

• 34 total active products are registered; 1 tech nical product, 3 manuf acturing use products, 26 end use products, and 4 special local needs permits (SLN; 24c).

• Quinclorac is sold in several different form ulations including water dispersible granules, emulsifiable concentrate and wettable powder.

• Quinclorac can be applied through aerial equi pment, tank spray, boom sprayer, hand held sprayer, and backpack sprayer.

Use & Usage Information: (For additional details, please refer to the BEAD Appendix A document in the quinclorac docket.)

• Quinclorac is a quinoline carboxylic acid, w hose mechanism of herbicidal action is generally mimicry of the plant growth hormone, auxin.

• Quinclorac is used on less than 2.5 % of the total crop treated for corn, summer fallow, sorghum and wheat. On average, it is used on 30% of the total crop treated for rice.

• Approximately 313,000 pounds of qui nclorac are used annually.

Recent Actions:

• A Rule for quinclorac was issued on 10/28/2007 (72 FR 55068) which established tolerances for residues in or on imported barl ey grain. BASF Corporation requested this tolerance under the Federal Food, Drug, and Cosmetic Act (FFDCA).

• A Rule for quinclorac was issued on 3/26/1999 (64 FR 14626), which established FQPA tolerances for residues on wheat and sorghum . This Rule also included the tolerance reassessment for rice, sorghum, wheat, residen tial lawns, ornamentals and turf grass.Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

10 Ecological Risk Assessment Status : Please refer to Section IV of this document, Ecological Risk Assessment Problem Formulation for quinclorac registration review, for a detailed discussion of the anticipated ecological risk assessment needs. Below is a summary of the findings:

• The Agency will need to conduct new assessmen ts for all registered uses because some uses and application type s cenarios were not assessed fo r ecological risk and did not

include current terrestri al and aquatic models.

• The Agency has some freshwater invertebrate data which indicates low risk for aquatic animals, however there are some unusual results with these studies, which were completed with a formulated product. Theref ore, the Agency is requiring freshwater invertebrate tests with the technical, and will use these tests to estimate risks to estuarine

animals.

• No acute or chronic risk exceedences of the Ag ency’s level of concern are anticipated for aquatic fish or invertebrates. However, uncertainty exists for acute and chronic risks to

estuarine marine invertebrates until further da ta is submitted. Chronic risks to estuarine

marine fish will be estimated from acute to chronic ratios.

• Before the risk assessments are developed for public comment, the Agency will ensure that all currently registered uses of quinclorac have an endangered species assessment completed. The ecological risk assessment will allow the Agency to determine whether quinclorac use has "no effect" or "may affect" federally listed threatened or endangered species (listed species) or their designated critical

habitat. If the assessment concludes that a pesticide's use "may affect" a listed species or its designated critical habitat, the Agency will consult with the U.S.

Fish and Wildlife Service and/or National Marine Fisheries Service (Services), as appropriate.

Human Health Risk Assessment Status: Please refer to Section V of this document, Human Health Effects Scoping Document, for a

detailed discussion of the antic ipated risk assessment needs for human health. A summary

follows:

Dietary (Food and Water):

• The residue chemistry database is complete with the newly submitted aspirated grain fraction (AGF) studies. A review of the AGF studies are needed, and livestock tolerances may need to be revised based on this review.

• The dietary exposure assessment is up-to-dat e, and no further dietary assessments are needed. There are no risks of concern even with a very conservative assessment.

• A drinking water assessment is needed.Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

11 Residential:

• The post application exposure assessments are adequate.

• No residential handler assessment has been c onducted; therefore, a residential handler assessment is needed for the registration review of quinclorac.

Occupational :

• No occupational assessments have been c onducted for quinclorac. A new occupational assessment is required for the registration revi ew once the inhalation endpoint is selected.

Aggregate:

• Once the drinking water assessment is comple ted, the Agency will conduct an aggregate

assessment.

Incident Reports:

• The search of the National Poison Control Center System (NPCS) showed only a total of five incidents related to quinclorac in the 13-year span of data collected and only two cases were reported in OPP’s Incide nt Data System (IDS) from 1999 to the present. In addition, there were no cases reported in the National Institute of Occupational Safety and Health Sentinel Event Notification System for Occupational Risks (NIOSH/SENSOR) database involving quinclorac. A more detailed summary is provided in a separate document in this docket.

Tolerances:

• US tolerances are listed under 40 CFR 180.463. A table listing the differences between current US tolerances as compared to Code x, Canada, and Mexico appears in section V of this document, Human Health Effects Scoping Document.

Data Call-In Status:

• There are no current data call-ins.

Labels :

• A list of registration numbers may be found in the quinclorac docket and the labels can then be obtained from the Pesticide Product Label System (PPLS) website: http://oaspub.epa.gov/pestlabl/ppls.home.

Registration # Product Name Company Name Percent

Active Ingredient

228-423 DQD SELECTIVE

HERBICIDE NUFARM

AMERICAS INC. 7.91Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

12 Registration # Product Name Company Name Percent

Active Ingredient

228-531 NUP 12D02

HERBICIDE NUFARM

AMERICAS INC. 8.25

239-2689 LAWN

CRABGRASS AND

WEED KILLER THE ORTHO

BUSINESS GROUP 0.1

538-296 TURF BUILDER

WITH WEED

CONTROL III SCOTTS COMPANY, THE 0.52

1381-209 QUINCLORAC 75

DF WINFIELD SOLUTIONS, LLC 75

2217-885 EH-1426

HERBICIDE PBI/GORDON

CORP 3.49

2217-886 EH-1427

HERBICIDE PBI/GORDON

CORP 5.69

2217-887 EH-1428

HERBICIDE PBI/GORDON

CORP 0.121

2217-888 EH-1425

HERBICIDE PBI/GORDON

CORP 8.38

2217-894 EH-1432

HERBICIDE PBI/GORDON

CORP 1.61

2217-896 EH-1437

HERBICIDE PBI/GORDON

CORP 2.13

2217-901 EH-1434

HERBICIDE PBI/GORDON

CORP 5.65

2217-906 EH-1449

HERBICIDE PBI/GORDON

CORP 0.104

7969-93 FACET 50 WP BASF

CORPORATION 50

7969-109 QUINCLORAC

MANUFACTURING

USE PRODUCT BASF

CORPORATION 98

7969-113 FACET 75 DF

HERBICIDE BASF

CORPORATION 75

7969-130 DRIVE 75 DF

HERBICIDE BASF

CORPORATION 75Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

13 Registration # Product Name Company Name Percent

Active Ingredient

7969-152 PARAMOUNT BW

HERBICIDE BASF

CORPORATION 15

7969-158 FACET GR

HERBICIDE 46 BASF

CORPORATION 1.5

7969-172 DRIVE 75

MANUFACTURERS

CONCENTRATE BASF

CORPORATION 75

7969-222 CLEARPATH

HERBICIDE BASF

CORPORATION 61.98

34704-920 QUINCLORAC

75DF HERBICIDE LOVELAND PRODUCTS, INC. 75

42750-85 QUINCLORAC

TECHNICAL ALBAUGH INC 99

42750-88 QUINCLORAC

75DF AG ALBAUGH INC 75

42750-90 QUINCLORAC

75DF SP ALBAUGH INC 75

42750-131 QUINCLORAC 75

SWF ALBAUGH INC 75

71085-26 RICEPRO RICECO LLC 2

73220-15 QUALI-PRO QUINCLORAC 75 FARMSAVER.COM,

LLC 75

79676-22 QUINCLORAC GPRO 75 DF GRO-PRO, LLC 75

81927-21 ALLIGARE QUINCLORAC 75 WDG ALLIGARE, LLC 75

AR070006 RICEPRO RICECO LLC 2

UT990003 FACET 75 DF

HERBICIDE BASF

CORPORATION 75

98ND20 ND Dept. of Agriculture

98NE07 NE Department of AgricultureDocket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

14 III. GLOSSARY of TER MS and ABBREVIATIONS

ai Active Ingredient AR Anticipated Residue CFR Code of Federal Regulations cPAD Chronic Population Adjusted Dose

CSF Confidential Statement of Formula CSFII USDA Continuing Surveys for Food Intake by Individuals

DCI Data Call-In DEEM Dietary Exposure Evaluation Model DFR Dislodgeable Foliar Residue DNT Developmental Neurotoxicity DWLOC Drinking Water Level of Comparison

EC Emulsifiable Concentrate Formulation EDWC Estimated Drinking Water Concentration

EEC Estimated Environmental Concentration EPA Environmental Protection Agency

EUP End-Use Product FDA Food and Drug Administration FIFRA Federal Insecticide, Fungicide, and Rodenticide Act FFDCA Federal Food, Drug, and Cosmetic Act FQPA Food Quality Protection Act FOB Functional Observation Battery GENEEC Tier I Surface Water Computer Model

IR Index Reservoir

LC 50 Median Lethal Concentration. A st atistically derived concentration of a substance that can be expected to cause death in 50% of test animals. It is usually expressed as the weight of substance per weight or volume of water, air or feed, e.g., mg/l, mg/kg or ppm.

LD 50 Median Lethal Dose. A statistica lly derived single dose that can be expected to cause death in 50% of th e test animals when administered by the route indicated (oral, dermal, inhalati on). It is expressed as a weight of substance per unit weight of animal, e.g., mg/kg.

LOC Level of Concern

LOAEL Lowest Observed Adverse Effect Level μg/g Micrograms Per Gram μg/L Micrograms Per Liter mg/kg/day Milligram Per Kilogram Per Day mg/L Milligrams Per Liter MOE Margin of Exposure MRID Master Record Identification (num ber). EPA's system of recording and tracking submitted studies.Docket Number: EPA-HQ-EPA- OPP-2007-1135 www.regulations.gov

15 MUP Manufacturing-Use Product NA Not Applicable NAWQA USGS National Ambient Water Quality Assessment NPDES National Pollutant Discharge Elimination System NR Not Required

NOAEL No Observed Adverse Effect Level OPP EPA Office of Pesticide Programs OPPTS EPA Office of Prevention, Pesticides and Toxic Substances PAD Population Adjusted Dose PCA Percent Crop Area PDP USDA Pesticide Data Program PHED Pesticide Handler's Exposure Data

PHI Preharvest Interval ppb Parts Per Billion PPE Personal Protective Equipment ppm Parts Per Million PRZM/EXAMS Tier II Surface Water Computer Model Q 1 * The Carcinogenic Potential of a Compound, Quantified by the EPA's

Cancer Risk Model RAC Raw Agriculture Commodity RED Reregistration Eligibility Decision REI Restricted Entry Interval

RfD Reference Dose RQ Risk Quotient SCI-GROW Tier I Ground Water Computer Model SAP Science Advisory Panel SF Safety Factor SLN Special Local Need (Registrat ions Under Section 24©) of FIFRA) TGAI Technical Grade Active Ingredient USDA United States Department of Agriculture UF Uncertainty Factor

WPS Worker Protection Standard

### IV. Ecological Risk Assessment Problem Formulation

U. S. ENVIRONMENTAL PROTECTION AGENCY Washington, D.C. 20460

OFFICE OF PREVENTION, PESTICIDES

AND TOXIC SUBSTANCES

Date: November 27, 2007

MEMORANDUM

Subject: EFED Problem Formulation for Qu inclorac Registration Review

PC: Code: 128974 D344485

To: Joy Schnackenbeck, Chemical Review Manager Special Review and Reregi stration Division (7508P)

From: Marie Janson, Environmental Scientist, ERBI Thuy Nguyen, RAPL, ERBI Nancy Andrews Ph.D., Branch Chief, ERBI Environmental Fate and Effects Division (7507P)

Attached is the EFED’s problem formulation docu ment in support of the Quinclorac registration review docket opening. This memorandum outlines (1) the methods that will likely be used in the ecological risk assessment of Quinclorac (2 ) data gaps, and (3) a dditional data needs.17 EXECUTIVE SUMMARY

Quinclorac is systemic pre- and post-emergent herbicide to control broa dleaf and grass weeds on residential/commercial turf grasse s and on other turf grasses (picni c grounds, athletic field, golf, and sod farms), agricultural fallow/ idleland, agri cultural rights of way/ fence rows/ hedge rows, grasses grown for seed, rice, sorghum and wheat . In addition to the above registered uses, Emergency Use Permits (EUPs) on impounded waters were also issued.

The most recent comprehensive risk assessment for registered uses was conducted on wheat andsorghum (Feb 17, 1999). The most recent EUP was conducted on aquatic weed control to nonflowing water bodies (May 17,2007). The drinking water assessment was conducted on turf grass application (September 13, 2007).

Based on the results of the above risk assessments the following risk concerns were noted from registered uses:

- risks to listed and non-listed terrestria l plants wheat and so rghum applications

- (listed and non-listed) acute risk to bi rds from wheat and sorghum applications*

Based on the results of the above EUP for aquatic weed control the followi ng risk concerns were

noted:

- risks to listed and non-listed terrestrial plants (spray drif t exceedences only)

- risks to non listed* and listed un icellular and vascular plants

- (listed and non-listed) acute and chronic risk to mammals*

- (listed and non-listed) acute and chronic risk to birds*

There is insufficient evidence to completely refu te these exceedences, however there is sufficient

evidence to refine the concerns.

Based on available laboratory studies, EFED ha s identified two major (BH 514-1 and BH 514 2- OH; >10% applied)) and one minor (BH 514-HMe-es ter; <10% applied) quinclorac metabolites. In most of the acceptable terrestrial fi eld dissipation studies (1988/1989, 1989/1990, and 1996/1997 studies), leaching from these de gradates. An acceptable guideline adsorption/desorption study for BH-514-1 indicates that this metabolite is mobile to very mobile in sand, sandy loam, loam, clay loam, and silty clay soils. Two guideline leaching and adsorption/desorption studies (MRID 45598701 and 45598702) for BH 514 2-OH and BH

514-HMe-ester were submitted to the Agency, in 2002, however not yet reviewed

. These studies will undergo review s and until they are deemed acceptable by the Agency, the above mentioned metabolites are considered pote ntial contaminants of groundwater resources, based on the “Acceptable” field studies. EFED be lieves that since quinclorac is persistent and

mobile and its metabolites have the ability to leach through soil profiles, the potential for groundwater impacts to non-target crops via contam inated groundwater is likely. Therefore, a small scale prospective groundwater contamin ation study for quinclorac (and possibly its metabolites) under the expected cond itions of use of all currently registered crops is requested.18 EFED anticipates revisions to the risk asse ssments based on new application scenarios and additional toxicity data requested. Previous assessments were based on lower application scenarios or higher interv als between applications.

PROBLEM FORMULATION

Problem formulation is used to es tablish the direction a nd scope of an ecological risk assessment. According to the Guidelines for Ecological Risk Assessment (USEPA, 1998), problem formulation consists of defining the problem and purpose for the assessment, and developing a plan for analyzing and characterizing risk. The critical components of the problem formulation are selection of the assessment endpoints, form ulation of risk hypotheses and the conceptual model, and development of an analysis plan. The analysis plan and supporting rationale are aimed at determining whether the uses of Quin clorac on residential/commercial turf grasses and on other turf grasses (picnic gr ounds, athletic field, golf, and sod farms), agricultural fallow/ idleland, agricultural rights of way/ fence rows/ hedge rows, grasses grown for seed, rice, sorghum and wheat could result in exposures th at cause unreasonable ad verse effects (risk) to non-target organisms including those federally lis ted as threatened or endangered (hereafter referred to as “listed”). Emergency Use Perm its also will also be characterized in the assessment on aquatic weed control on impounded waters.

1. INTEGRATION OF AVAILABLE INFORMATION

The risk assessments available in the docket, and which serve as the basis for this problem formulation, include the following:

• Feb 17, 1999, Quinclorac Herbicide Environmen tal Fate and Ecological Effects Assessment and Characterization for a Section 3 for Use on Wheat and Sorghum

• May 17, 2007, Ecological Risk Assessment fo r Experimental Use Permit for Quinclorac for Aquatic Weed Control for th e application of quinclorac to non- flowing water bodies such as retention ponds and lake s to evaluate the control a nd selectivity of submerged and emergent aquatic weed species DPBarcode: D334717.

• September 13, 2007, Estimated Drinking Water Assessmen t for Quinclorac (3,7-dichloro-8- quinolinecarboxylic acid, CAS# 84087-01-4) Use on Turfgrasses DPBarcode: 341487

Based on the results of the above risk assessments the following risk concerns were noted from registered uses:19 - risks to listed and non-listed terrestrial pl ants from wheat and sorghum applications

- (listed and non-listed) acute risk to bi rds from wheat and sorghum applications*

Based on the results of the above EUP for aquatic weed control the followi ng risk concerns were

noted:

- risks to listed and non-listed terrestrial plants (spray drif t exceedences only)

- risks to non listed* and listed un icellular and vascular plants

- (listed and non-listed) acute and chronic risk to mammals*

- (listed and non-listed) acute and chronic risk to birds*

There is insufficient evidence to completely refu te these exceedences, however there is sufficient

evidence to refine the concerns.

The following maximum use rates were used in previous assessments:

Feb 17, 1999, Section 3 Assessment for Use in Wheat and Sorghum: The maximum annual application rate is 0.75 lb a.i. /acre at 0.125 - 0.245 lb ai/acre for ground and aerial applications.

September 13, 2007, Estimated Drinking Water Assessment for Quinclorac Use on Turfgrasses: The maximum annual application rate is 1.5 lb a. i./acre at 0.25 – 0.75 lb ai/A/ appl at 21-day interval for ground spray or spot spray application.

May 17, 2007, Ecological Risk Assessment fo r Experimental Use Permit for Quinclorac for Aquatic Weed Control: For submerged vegeta tion control quinclorac is applied in sufficient quanity to reach a water concen tration of 0.5 mg/L with up to 2 applications per year.

All assessments did not provide th e highest labeled application ra tes (2 applications @0.75 lb ai/A) and current minimum intervals (14 days). In addition, current labels have ground, aerial and granular applications which were not incorporated in all a ssessments. Therefore, a new drinking water assessment and eco logical risk assessment is re quired with the above maximum application rates, minimum interv als and application scenarios.

There are two reported incidents for quinclorac. Both incidents ref# I012162-001 and ref# I015496-001 indicated plant damage to tomatoes in Arkansas from drift exposure. There are additional data that suggest the effects of primary drift may occur at considerable distances downwind from the target site and effect commercial yields of sensitive crops. Additional

information is summarized in the 1999 EFED risk assessment in the Risk Characterization Section on Non-Target Plant Effects (Drift Impli cations for Risks to Non-Target Crops and Wild Plants).20 2. DATA GAPS AND ANTICIPATED DATA NEED

Acute and chronic freshwater invertebrate toxicity tests- The acute freshwater invertebrate toxicity test was based on a formulated prod uct (quinclorac with su rfactant BAS 864 01 S).

The Daphnia magna 21-day NOAEC of 110 mg/L is used as the freshwater invertebrate toxicity endpoint for chronic exposure. It should be noted that the 21-day NOAEC unexpectedly exceeds

the 48-hour EC 50 for the same species. This observation is likely the result of differences in test water conditions, or as the result of surfactant use in the acute toxicity test. As quinclorac is an acid subject to dissociation in wa ter, differences in water hardne ss may influence the toxicity of the compound. The available data suggest th at quinclorac is more toxic to freshwater invertebrates in soft water (48-hour LC 50 = 28.9 mg/l in water 40-48 mg CaCO 3 /L) compared to harder water (21-day NOAEC 110 mg/l in water >150 mg CaCO 3 /L). An alternative explanation for the disparate toxicity results may be the pr esence of surfactant in th e acute test, whereas no

surfactant is evident for the chronic test. The use of the available 21-day chronic data as the toxicity endpoint for all freshwater systems represents an uncertainty.

Decision: Acute and chronic freshwater inverteb rate studies conducted on TGAI and current guideline requirements are requested. This data will then be used to estimate values for estuarine marine invertebrate chronic toxicity.

Estuarine marine fish and estuarine marine invertebrate Early Life-Stage toxicity test s- No early life-stage or full life-cycle studies were submitted for estuarine marine fish or invertebrates.

Decision: Early life-stage chronic estuarine marine fish and invertebrate toxicity tests for quinclorac are not requested. Estimated values derived from ACRs will be sufficient pending

acute and chronic freshwater i nvertebrate study based on TGAI.

Ground water contamination study for qui nclorac (and possibly its metabolites) : Based on available laboratory studies, EFED ha s identified two major (BH 514-1 and BH 514 2- OH; >10% applied)) and one minor (BH514-HMe-es ter; <10 % applied) quinclorac metabolites. In the field (1988/1989, 1989/1990, and 1996/1997 studies ), leaching from these degradates intothe soil profiles were observed. An acceptable guideline adsorption/desorption study for BH514-1 indicated that this metabolite is mobile to very mobile in sand, sandy loam, loam, clay loam, and silty clay soils. Two guideline le aching and adsorption/desorption studies (MRID

45598701 and 45598702) for BH 514 2-OH and BH 514-HMe-ester were submitted to

the Agency, in 2002, however not yet reviewed . These studies will undergo reviews and until they are deemed acceptable by the Ag ency, the above mentioned metabolites are considered potential contaminan ts of groundwater resources, as suggested by data from the “Acceptable” terrestrial field dissipation studies.21 Decision: Based on the environmental persistence of quinclorac, its potential to enter groundwater (as modeled by SCI-GROW and indicated in terrestrial field studies), and the potential for groundwater impacts to non-ta rget crops via contaminated groundwater, a small scale prospective groundwater contamination stu dy for quinclorac (and possibly its metabolites) under the expected conditi ons of use of all currently register ed crops is requested. Specifically, since both parent quinclorac and BH 514-1 are carboxyl ic acids, they are expected to be anions under the normal environmental pH range (5.5 – 8.5), therefore possess high potential to be

mobile in mineral soils.

3. PESTICIDE TYPE, CLASS, AND MODE OF ACTION

Quinclorac is a quinoline carboxylic acid. The mechanism of herbicidal action is generally similar to the mechanism for the phenoxy herbicides (i.e., mimicry of the plant growth hormone auxin). The risk assessment only assesses parent qui nclorac risks. For most fate processes the parent compound is stable. While quinclorac may be relatively rapidly ph oto-labile in natural waters, the available studies of this fate process have not chemically identified degradates or their rate of production. There is therefore insufficient informati on to assess degradate risks with any useful degree of confidence and no information is available to suggest that any degradates could be biologically active.

4. STRESSOR SOURCE AND DISTRIBUTION

The stressor of this assessment is iden tified by the chemical name 3,7-dichloro-8- quinolinecarboxylic acid. The trade name for this compound is quinclorac, the CAS number is 84087-01-4, and the PC code is 128974. Currently, qui nclorac is applied as ground spray, aerial spray, aerial granular, gr ound granular applications.

Laboratory data indicate that qu inclorac is stable to hydrolysis, photolysis in sterile water, as

well as aerobic and anaerobic metabolism in so il. Conversely, quinc lorac undergoes rapid photolysis in non-sterile rice pa ddy, natural river waters, and solutions containing activated sewage sludge (half-lives of 5-10 days). Photol ysis on soil surface is also a route of dissipation with a mean half life of 141 days. Field studie s reviewed to date indi cate that quinclorac is moderately persistent (18-176 days half -lives) in terrestrial environment.

The adsorption coefficients K d of less than 1 suggest that leaching could be a route of dissipation. In the field, some leaching was obs erved, as quinclorac was detected below the 12 inch soil depth in the several of the terrestri al field dissipation studi es (1988/1989 studies): detections of residues of qui nclorac and its degradates in the soil down to 42-48 inches (quinclorac), 12-18 inches (BH 514-2-OH) a nd 6-12 inches (BH 514-ME) were noted in terrestrial field studies performed in KS, CA, MO, and NJ.

Runoff under normal field situations to near surface water is also expected, since K d is low (<1.0) and the chemical can be applied n ear the soil surface (pre emergence).22 5. OVERVIEW OF PESTICIDE USAGE

Quinclorac is a pre- and post-emergent herb icide to control broadl eaf and grass weeds on residential/commercial turf grasse s and on other turf grasses (picni c grounds, athletic field, golf, and sod farms), agricultural fallow/ idleland, agri cultural rights of way/ fence rows/ hedge rows, grasses grown for seed, rice, sorghum and wheat. In addition, quinclorac controls submerged and emergent aquatic weed species in impounded waters for EUPs.

The highest annual application ra te among all registered and proposed uses is via Drive 75 DF and Quinclorac G-Pro 75 DF labels, which allo ws 2 to 3 ground broadcast or spray spot applications of 0.25, 0.50, or 0.75 lb ai/A pe r application, not exceeding 1.5 lb ai/A/year. Sequential applications should be timed 14 days apart. Additional maximum rate application scenarios are provided in Table 1 for aerial, ground and granular applications based on BEAD

2007 information. Table 30 provides all current registra tions and EUPs based on BEAD 2007

information.

Table 1 Maximum Quinclorac Aerial , Ground and Granular application rate

scenarios derived from BEAD 2007 to be used in future risk assessments*

Type of application Label Maximum applicatio

n rate Maxim

um #

apps Maximum application per season aerial spray

and aerial granular applications 7969-158 Facet GR(aerial), 42750-88 Quinclorac 75 DF AG,7969-93 Facet 50

WP 0.5 lb ai/A 1 0.5 lb ai/A

aerial spray application 42750-131 Quinclorac

SWF 0.375 lb

ai/A 2 0.75lb ai/A

ground granular application 583-296 Scotts turf

builder 0.75 Lb

ai/A 2 Not specified (assume 2@ 0.75) 60 day interval

ground spray application 7969-130 Drive 75

DF and 79676-00022 Quinclorac G-Pro 75

DF 0.75lb

ai/A 2 1.5 lb ai/A

*assume 14 day interval unless indicated

The application rate for emergent vegetation co ntrol is indicated on the proposed label for the EUP to be a maximum of 3 lbs a.i. per year, w ith up to two applications in a calendar year. Applications can be made to drawn down water bodi es to expose vegetation. In such cases reflooding may occur 14 days after application. The application rate for submerged vegetation is quinclorac applied in sufficient quantity to reach a water concentration of 0.5 mg/L. Up to two application of quinclorac per year can be made.23 6. ENVIRONMENTAL FATE SUMMARY

ENVIRONMENTAL FATE

For persistence , laboratory data indicate that quinclorac is stable to hydrolysis, photolysis in sterile water, as well as aerobic and anaerobi c metabolism in soil. Conversely, quinclorac undergoes rapid photolysis in non-sterile rice paddy, natural river waters, and solutions containing activated sewage sludge (half-lives of 5- 10 days). Photolysis on soil surface is also a route of dissipation with a mean half life of 141 days. Field studi es reviewed to date indicate that quinclorac is moderately persistent (18-176 days half-lives) in terrestrial environment.

For mobility in terrestrial environment , the adsorption coefficients K d of less than 1 suggest that leaching could be a route of dissipation. In the field, some leaching was observed, as quinclorac was detected below the 12 inch soil depth in the several of the terrestrial field dissipation studies (1988/1989 studies): detections of residues of quinclorac and its degradates in the soil down to 42-48 inches (quinclorac), 12- 18 inches (BH 514-2-OH) and 6-12 inches (BH 514-Me ester) were noted in terrest rial field studies performed in KS, CA, MO, and NJ. It is not

clear from these studies whether or not the meta bolite BH 514-1 was analyzed for at the time the studies were conducted. However, as referenced in the April 25, 1996 letter to Mr Robert Taylor, RD, EPA, the registrant claimed a reanalysis (no analysis date was specified) of the soil samples from the 1988/1999 studies did not detect presen ce of this carboxylic acid metabolite. Additional studies performed between 1989 and 1990 in FL, WI, and NY only showed movement of parent quinclorac to a maximum depth of 24 inches, while the degradate BH-514-1 was not found at any sampling interval and/or samp ling depths. These studi es and the details of the reanalyses of BH 514-1 have not yet been received nor reviewed by EFED. Two guideline leaching and adsorption/desorption studies (MRID 45598701 and 45598702) for BH 514 2- OH and BH 514-HMe-ester were submitted to the Agency, in 2002, however not

yet reviewed . EFED SCI-GROW model predicts an upper bound ground water exposure concentration of 29 μg/L for parent quinclorac. In summary, based on all “Acceptable” guideline studies, EFED concludes that quinclorac has has the potential to leac h and runoff in the soil environment an d into groundwater. Furthermore, BH 514-1, the primary degradate of quinclorac, al so has the potential to leach to the groundwater in soil containing low amount of clay or organi c matter. EFED notes that quinclorac and BH514-1 are both carboxylic acids; ther efore, they are expected to be anions under the normal environmental pH range (5.5-8.5). This suggests that these two chemicals have great potential to

be mobile in mineral soils.

Runoff under normal field situations to near su rface water is also expected, since K d is low (<1.0) and the chemical can be applied near the soil surface (pre emergence). For 1 in 10 year annual peak (acute) surface water residue, EFED PRZM/EXAMS estimates a value of 22.9 μg/L; for 1 in 10 year annual mean (chronic), 14.5 μg/L; and for 30 year annual mean (cancer), 10.324 μg/L. Note that all values were based on post em ergence non residential turf uses ,such as picnic grounds, athletic fields, sod farms, etc, ... The acute value was estimated from the FL Turf scenario, and the chronic and cancer from the PA Turf scenario.

According to the aerobic soil metabolism and field dissipation studies and the research cited in the literature reviews, the fate of quinclorac can be described as such:

1. Quinclorac is initially metabolized to the primary degradate, 3-chloro-8-quinoline carboxylic acid (BH 514-1). This degradate undergoes further degrad ation to 5-chloro2-hydroxy-nicotinic acid, which in turn is metabolized to 5- chloro-2,6-dihydroxynicotinic acid, 2 hydroxy-3-chloro-8-qui noline carboxylic acid (BH 514 2-OH), 7- chloro-8-quinoline carboxylic acid, 8-qui noline carboxylic acid, and other small fragments. These compounds can then bind with or become incorporated into the soil or humic material of the soil as a part of na tural soil components (i.e., carbon pool of the soil), and/or can degrade to CO 2 , a major terminal product.

2. The only volatile compound detected in the aerobic soil metabolism study (MRID 44084503) was CO 2 at a maximum concentration of 7.1% TRR. Other than parent,

residues identified at maximum concentra tions were: BH 514 2-OH (14.9% TRR), BH 514-Me ester (7.8% TRR). Parent was f ound at maximum concentrations of 58.1%

TRR.

3. BH 541-1 was also reported in the aer obic aquatic metabolism (MRID 42294102), at

maximum of 55.7% of the initial radioact ivity after 6 months and 30.8% after 12 months. Adsorption/desorption studies determin e that this degradate is less mobile than its parent, with K d ’s ranging from 1.56 in sand soil, 1.97 in sandy loam soil, 11.4 in loam soil, 13.3 in clay loam soil, and 30.2 in silty clay soil. This degradate was not reported in any of the terrestrial field dissip ation studies, at any soil depth.

For mobility in aquatic environment , aquatic field dissipations studies with rice indicate that the compound is less stable than predicted by the laboratory and is probably not mobile under

normal use conditions.

For volatility , both vapor pressure (7.5 x 10 -8 mm Hg at 20 o C) and Henry's Law Constant (1.22

to 24.3 x 10 -15 atm.m 3 mol -1 ) indicate a low possibility of vol atilization from soil and water.

Bioaccumulation in fish is not expected according to the acceptable fish accumulation study, which showed that after 28 days of exposure, qui nclorac did not accumulate in channel catfish. No BCF value was reported (MRID 40320819 and 41063559). Furthermore, the octanol/water partition coefficient (K OW ) of 0.266 also suggests that qu inclorac has low potential to

bioaccumulate.

A detailed assessment of the environmental fate of Quinclorac could be found in the “Environmental Fate and Ecological Effects Asse ssment and Characterization for a Section 3 for Use on Wheat and Sorghum” report date d March 05, 1999 (DP Barcodes: 250179, 248882, 248884, 192866, 231399, and 238400). The chemical structures of quinclorac and its 2 major metabolites (BH 514-1 and BH 514 2-OH) are shown in Table 29.25 7. ECOLOGICAL EFFECTS SUMMARY

Table 2 provides taxonomic groups and test species us ed to indicate the potential for ecological effects in this screening-level risk assessmen t. Within each of these very broad taxonomic groups, an acute and/or chronic endpoint is selected from the available test data.

Table 2. Taxonomic Groups and Most Sensit ive Test Species Evaluated for Ecological Effects of Quinclorac *

Taxonomic group Example(s) of representative species Endpoint Used

Birds a Bobwhite quail ( Colinus virginianus ) Mallard duck ( Anas platyrhynchos ) Bobwhite quail ( Colinus virginianus ) Acute LC 50 5000 mg/kg-diet

Acute LD 50 >1900 mg/kg-bwChronic, NOAEC 500 mg/kgdiet

Mammals Laboratory rat ( Wistar ) Acute LD 50 2190 mg/kg-bw NOAEC 160 mg/kg-bw/day

Terrestrial insects Honeybees ( Apis mellifera ) Acute Contact LD 50 >181 ug/bee

Freshwater fish b Bluegill sunfish ( Lepomis macrochirus )

Fathead minnow (Pimephales promelas) Acute LC 50 31.6 mg/L

Chronic NOAEC 16 mg/L

Freshwater invertebrates Water flea ( Daphnia magna ) Acute EC 50 29.8 mg/L NOAEC 110 mg/L

Estuarine/marine fish Shee pshead minnow (Cyprinodon variegatus) Acute LC 50 >94.4 mg/L

NOAEC no studies submitted

or values determined. However, estimated values

derived from acute to chronic

ratios will be used in future

risk assessments.26 Table 2. Taxonomic Groups and Most Sensit ive Test Species Evaluated for Ecological Effects of Quinclorac *

Taxonomic group Example(s) of representative species Endpoint Used

Estuarine/marine invert ebrates Mysid shrimp ( Mysidopsis bahia ) Acute EC 50 69.4 mg/L

NOAEC no studies submitted

or values determined. However, estimated values

derived from acute to chronic

ratios will be used in future

risk assessments.

Terrestrial plants* Dicots – carrot

Dicots- tomato Seedling Emergence EC 25 0.004 lb a.i./acre, NOAEC

<0.004 lb a.i./acre

Vegetative Vigor EC 25 EC 25 0.007 lb a.i./acre,

NOAEC 0.5 lb a.i./acre

Vascular aquatic plants Duckweed (Lemna gibba) Tier1 Acute EC 50 >0.5 mg/L NOAEC 0.5 mg/L

Non-vascular aquatic plants Green algae ( Selanastrum capricornutum )

Freshwater diatom (Navicula pelliculosa)

Marine diatom (Skeletonema costatum) Bluegreen alga (Anabaena flos-aquae) Acute EC 50 >0.5 mg/L NOAEC 0.5 mg/L

a Birds are used as surrogates for terrestrial pha se amphibians and reptiles (US EPA, 2004).

b Freshwater fish are used as surrogates for aquatic phase amphibians (US EPA, 2004). * Dicots were the most sensitive terrestrial plant species te sted, however the most sensitive monocots for seedling emergence i s onion (EC 25 0.118 lb, NOAEC<0.118 lb ai/A) and for vegetative vigor is corn ( EC 25 1.09 lb a.i./acre, NOAEC 0.5 lb ai/A)

8. ECOSYSTEMS AT RISK

The ecosystems that could be potentially at risk du e to agricultural and ornamental turf use of quinclorac include terrestrial and aquatic (lakes, ponds, stream s and estuarine marine water bodies) habitats in proximity to quinclorac use areas. These habita ts may be at risk from drift and/or runoff of quinclorac from use areas.

Organisms of concern include birds, mammals, reptiles, fish, and terrestrial and aquatic invertebrates, plants, and amphibians. The assessment endpoints are intended to reflect population sustainability and community structure within ecosystems and hence relate back to ecosystems at risk. If risks are expected fo r given species/taxa base d on the screening-level assessment, then risks might be expected to tran slate to higher levels of biological organization.27 Identifying specific ecosystems at risk in a scr eening-level assessment is beyond the scope of the

effort.

8.1 Receptors

The aquatic receptors likely to be exposed to quinclorac from turf and rice applications include fish, invertebrates, aquatic stages of amphibians and plants living in waterways adjacent to or

downstream from treated areas.

Terrestrial receptors likely to be exposed to quinclorac include birds, mammals, reptiles, and terrestrial stages of amphibians that may occur in treated fields and terrestrial plants adjacent to, or down slope from treated areas. The above taxonomic groups exposed to quinclorac are simular for impounded waters as well.

8.2. Assessment Endpoints

Assessment endpoints are defined as “explicit expre ssions of the actual en vironmental value that is to be protected.” Operationally, the environm ental value is represente d by an ecological entity

and associated attributes or characteristics. The assessment endpoints for this ecological risk assessment will be survival, growth, and reprodu ction of terrestrial and aquatic animals and plants. Specifically, this assessment will addr ess birds, mammals, reptiles, amphibians, terrestrial and aquatic invertebrates, terrestrial an d aquatic plants, and fish. These endpoints, in turn, are meant to reflect populat ion sustainability and community diversity within ecosystems.

Assessment endpoints and toxicity data used to evaluate the as sessment endpoints are identified

in Table 2

.28 9. CONCEPTUAL MODEL

Figure 1. No conceptual model was provided in previous assessments, however this new conceptual model of the fate/transport and e ffects of Quinclorac applied to the terrestrial environment will be applied in future assesssments. In addition, granular applications will be

assessed in future risk assessments.

Food Web Dynamics Perturbing Forage or Prey Availability Habitat Alteration: impacting nesting ability, ability to seek cover, etc. Individual Terrestrial Animals

Reduced Survival

Reduced Growth Reduced Reproduction Individual Terrestrial Plants Seedling Emergence Vegetative Vigor Individual Aquatic Vertebrates and

Invertebrates

Reduced Survival

Reduced Growth Reduced Reproduction

Bioaccumulation Aquatic Plant Population

Reduced

Growth Rates and

Biomass Terrestrial Animals Birds, Mammals, Reptiles, Terrestrial-phase Amphibians,

Bees Terrestrial Upland

Plants Wetland/ Riparian

Plants Aquatic Invertebrates Aquatic Vertebrates Aquatic Plants Quinclorac applied by spray (ground and a erial) and granular (ground and aerial) applications

Volatilization/ Wind Suspension* Ground Deposition Spray Drift Runoff/

Erosion Leaching (Infiltration/ Percolation)

Terrestrial Food Residues (foliage, fruit, insects) Upland Foliage/

Soil Riparian/

Wetland Foliage/Soil Surface Water,

Sediment

Dietary uptake Direct Contact/ Root Uptake Gill/ Integument Uptake Direct Contact/ Root Uptake Groundwater

Direct Ingestion29 *The vapor pressure of quinclorac, reported to be 1 x 10 -7 mbar (0.76 x 10 -7 mm Hg) at 20 o C, and Henry's Law Constant both indicate a low possibility of volatilization.

For direct application to the aquatic environment, the conceptual model of the fate/transport and effects of Quinclorac will be used from th e May 17, 2007 Ecological Risk Assessment for Experimental Use Permit for Quinclorac for Aquatic Weed Control DP Barcode: D334717.

10. RISK HYPOTHESES

Used in accordance with proposed or existing labels quinclorac may:

• adversely affect growth, survival, or fec undity of birds and/or small mammals (and terrestrial amphibians and reptiles) ingesti ng the incidentally contaminated vegetation, seeds, fruits, or invertebrates associated with direct application to terrestrial plants, soil surface, drained impounded water bodies or the in tentionally treated bait or seed stock,

• adversely affect growth, survival, and or re production of aquatic invertebrates, fish, amphibians in both freshwater and estuarine marine environments,

• adversely affect the emergence or growth of terrestrial plants rece iving exposure either by

drift from treated areas under cond itions of ground or aerial spray.

11. ANALYSIS PLAN

The analysis plan is the final step in problem formulation. During this step measures of exposure and measures of effect are used to evaluate the ri sk hypotheses and are listed in Tables

2 and 3 for a specific assessment endpoint. The RQ is obtained by dividing the measures of exposure for a particular assessment endpoint by the measures of effect for that endpoint.

11.1. Measures of Exposure

Measures of exposure for quinclorac that will be used in this assessment are obtained from modeling efforts only, since national-scale mon itoring data were not identified. Exposure

models used for this assessment include the suite of standard exposure m odels commonly used in pesticide risk assessments (EPA, 2004). Genera lly, aquatic exposure estimates are generated from EFED models and incorporate maximum pr oposed use rates and empirically-derived fate30 properties. Aquatic exposure will be estimated using the Tier 1 GENEEC model and will consist of aquatic EECs derived using a water body that is vulnerable and representative of static ponds and first order waterways.

Measures of exposure for terrestrial mammals , birds, reptiles, and amphibians similarly incorporate maximum proposed use rates but rely less on fate properties. Instead, terrestrial exposure estimates are derived directly from em pirically determined observations of pesticide

residues on various terrestrial food items. For numerous applications for a given use, the exposure model incorporates a fi rst-order decay rate dependent on the soil half-life of the chemical. In place of unavailable foliar dissipation data, the default foliar dissipation half-life of 35 days will be used. The currently used te rrestrial exposure mode l is TREX v.1.3.1.

Exposure to terrestrial plants will be estimated using the Te rrPlant model that assumes quinclorac drifts or moves with runoff to adjacent areas.

Listed Species Assessment

Based on preliminary EECs from terrestrial appli cation scenarios and the assumptions discussed above, acute risks at the highest la beled application rate are expect ed for listed birds based on the non-definitive LD50 of >1900 mg/kg-bw (1.5 lbs a.i. /A per season) Risks are expected as well for listed species of terrestrial plants (monocots and dicots) inha biting semi-aquatic and dry areas based on exposures of quinclorac originati ng from the maximum application rate.

Based on preliminary EECs from direct appl ication to a water body and the assumptions discussed above, acute risks at th e highest labeled application rate are expected for listed birds, mammals, terrestrial plants (monocots and dico ts) and aquatic non-vascular plants.

Because of the potential risk from direct effect s to the listed and non-listed taxa described above, should exposure occur, listed sp ecies in all taxa may potentially be affected indirectly due to alterations in their habitat ( e.g ., food sources, shelter, and areas to reproduce). An evaluation of

risk conclusions based on direct and indi rect effects for each taxonomic group will be summarized in the future assessment for all proposed labels.

If the planned ecological risk assessment continues to indicate that quinclorac may potentially impact, either directly or indirectly, listed spec ies or critical habitat, and therefore does not support a “not likely to adversely affect” determination, further refinements will be made. This will involve determining whether use of quinclorac “may affect” a particular listed species, and if so, whether it is “likely to adversely affect” the species, or in the case of designated critical habitat, whether use of the pesticide may destroy or adversely modify any principle constituent elements for the critical habitat, and if so, whet her the expected impacts are “likely to adversely affect” the critical habitat. The first step in the process is to impr ove the exposure estimates31 based on refining the geographic proximity of quincl orac use and the listed species and/or critical habitat. If there is no geographic proximity, th is information would support a determination that quinclorac use will have no effect on the species or critical habitat. If after conducting the first step of this analysis the Agency determines that geographic proximity exists, both potential direct effects and any potential indirect effect s of the pesticide use will be examined. This process is consistent with the Agency's Over view Document. The Agency will consult as necessary with the U.S. Fish and Wildlife Service and National Marine Fisheries Service (collectively ‘the Services’), consistent with the Services' regulations.

If the screening level risk assessment identifies potential concerns for indirect effects on listed species, the next step for EPA and the Services would be to identify which listed species and critical habitat are potentially implicated. Anal ytically, the identification of such species and critical habitat can occur in either of two ways. First, the agencies could determine whether the action area overlaps critical habita t or the occupied range of any listed species. If so, EPA would examine whether quinclorac potential impacts on non-endangered species would affect the listed species indirectly or directly aff ect a constituent element of the cri tical habitat. Alternatively, the agencies could determine which listed speci es depend on biological resources, or have constituent elements that fall into, the taxa th at may be directly or indirectly impacted by quinclorac. Then EPA would determine whethe r the use of quinclorac overlaps the critical habitat or the occupied ra nge of those listed species.

11.2. Measures of Effect

EFFECTS ASSESSMENT

The Effects assessment for this risk assessment ha s been based on previous risk assessment data

evaluations conducted in 1999. There has been no update of the toxicolo gical review of the compound in the intervening years. These ri sk assessments DO NOT include a search and

evaluation of the ECOTOX database.

Toxicity to Terrestrial Animals

Acute and Subacute Avian Toxicity

The results of available avian acute toxicity tests are listed in Table 3 . The most sensitive species is the mallard duck (LD 50 >1900 mg/kg, LD 50 value expressed on a bodyweight-based dose), which serve as the toxicological endpoi nt in avian single oral dose exposure risk

calculations.

Table 3 Avian Acute Oral Toxicity Data

Species % Active Ingredient LD 50 (confidence limits) MRID No. Classification32 (mg/kg-bw)

Northern bobwhite quail Colinus virginianus 98 >2000 (no mortality at 2000) 41063547 acceptable

Mallard duck Anas platyrhynchos 98 >1900 (no mortality at 970, 20% mortality and convulsions at 1900) 40320810 supplemental*

LD 50 : Lethal dose to 50% of test population

NOAEL: No observed adverse effect level * listed as supplemental due to questionable husbandry practices (e.g., the necks of ducks bound with bands to prevent regurgitation)

The results of available avian sub-ac ute dietary testing are summarized in Table 4 . The LC 50 of >5000 mg/kg-diet exhibited for both northern bobw hite quail and the mallard duck serve as the basis of the toxicological endpoint for sub- acute dietary exposure risk calculations.

Table 4 Avian Subacute Dietary Toxicity Data

Species % Active Ingredient LC 50 (confidence limits) (mg/kg-diet) MRID No. Classification

Northern bobwhite quail Colinus virginianus 96 >5000

(no mortality to 2500) 40320812 acceptable

Mallard duck Anas platyrhynchos 96 >5000
(no mortality to 5000) 40320811 acceptable

LC 50 : Lethal dietary concentration to 50% of test population

NOAEC: No observed adverse effect concentration

Chronic Avian Exposure Effects

The results of avian reproduc tion testing are listed in Table 5 . The northern bobwhite reproduction NOAEL of 500 mg/kg-diet serves as the reproduction toxicity endpoint for avian reproduction risk calculations. This NOAEL is es tablished with respect to the most sensitive toxicity endpoint observed for the study, reduced su rvival of 14-day old hatchlings from eggs set.

Table 5 Avian Reproduction Toxicity Data

Species % Active Ingredient LOAEC (mg/kg-diet) NOAEC (mg/kg-diet) MRID No. Classification

Northern bobwhite quail Colinus 99.19 1000 (reduced 14 day 500 44129201 acceptable33 virginianus survivors of egg set)

Mallard duck Anas platyrhynchos 99.19 >1000 1000 44084501 acceptable

LOAEC: Lowest observed ad verse effect concentration

NOAEC: No observed adverse effect concentration

Acute and Chronic Mammalian Toxicity

Acute mammalian toxicity data are summarized in Table 6 . The most sensitive acute endpoint is for the laboratory rat (Wista r strain), with a minimum LD 50 of 2190 mg/kg bodyweight.

Table 6 Mammal Acute Toxicity Data

Species % Active Ingredient LD 50 (mg/kg) MRID No. Classification

Rat (Wistar) technical male: 3060

female: 2190 41063506 acceptable

Mouse (B6C3F1) technical >2000 41063507 acceptable

LD 50 : Lethal dose to 50% of test population

NOAEL: No observed adverse effect level

The following table summarizes the reproduction, a nd developmental toxicity data for laboratory mammals chronically exposed to quinclorac. For the purposes of this risk assessment, the rat 2- generation reproduction study NOAEL of 160 mg/ kg-bw/day for reduced pup viability was

selected as the threshold for mammals chronicall y exposed to quinclorac. This value is quite similar to the threshold for rabbit developmental data, in which the NOAEL for increased fetal resorptions was 200 mg/kg-bw/day.

Table 7 Mammal Chronic, Reproduction, and Developmental Toxicity Data

Species %

Active Duration/ Study Type LOAEL (mg/kg-diet) or (mg/kg-bw/day) NOAEL (mg/kg-diet) or (mg/kg-bw/day) MRID

No. Classification

Rat (Wistar) 96.5 3 month feeding 12000 mg/kg-diet slight nephritis 4000 mg/kg-diet 41063516 supplemental

Rat (Wistar) 96.5 Developmental >438 mg/kg-bw/day 41063524 minimum

Rabbit 98.3 Developmental 600 mg/kg-bw/day

increased fetal resorptions 200 mg/kg-bw/day 41063525 minimum34 Rat (Wistar) 97.40-

98.3 2 generation reproduction 480 mg/kg-bw/day reduced pup viability 160 mg/kgbw/day 41063526

41910001 minimum

LOAEL: Lowest observed adverse effect level

NOAEL: No observed adverse effect level

Beneficial Insect Toxicity

The available studies of qui nclorac effects on honeybees ( Table 8 ) indicate that technical quinclorac and the 50% formulati on are relatively non-toxic to bees on an acute contact basis

Table 8 Beneficial Insect Toxicity Data

Species % Active Ingredient LD 50 (μg/bee) NOAEL (μg/bee) MRID No. Classification

Honeybee Apis mellifera 98 >357 238 41063575 acceptable

Honeybee Apis mellifera 50 >181 <60.4 (lowest dose tested) 41063576 acceptable

LD 50 : Lethal dose to 50% of test population

NOAEL: No observed adverse effect level

Terrestrial Plant Toxicity

Table 9 summarizes the available data for the eff ects of quinclorac on terrestrial plants. The toxicological threshold for seedling emergence used in the risk assessment is based on the carrot

EC 25 of 0.004 lb a.i./acre. The t oxicological threshold for vegeta tive vigor used in the risk

assessment is based on the tomato EC 25 of 0.007 lb a.i./acre.

Table 9 Terrestrial Plant Toxicity Data

Species % Active Ingredient Test Type EC 25 (lb a.i./acre) NOAEC (lb a.i./acre) MRID No. Classification for

all

96 SE 0.047 <0.047 41403501 Soybean Glycine max
96 VV 0.203 0.125 41403503

96 SE 0.013 <0.01 41403501 Lettuce

Lactuca sativa
96 VV 0.01 <0.01 41403503

96 SE 0.004 <0.004 41403501 Carrot

Daucus carota
96 VV 0.027 0.02 41403503 acceptable35 Species % Active Ingredient Test Type EC 25 (lb a.i./acre) NOAEC (lb a.i./acre) MRID No. Classification for

all

96 SE 0.026 0.02 41403501 Tomato Lycopersion

esculentum 96 VV 0.007 0.005 41403503

96 SE 0.012 <0.012 41403501 Cucumber

Cucumis sativus
96 VV 0.028 0.012 41403503

96 SE 0.162 0.125 41403501 Cabbage

Brassica

oleracea 96 VV 26.0 2.0 41403503

96 SE 0.771 <0.77 41403501 Oat

Avena sativa
96 VV 68.3 2.0 41403503

96 SE 0.271 <0.27 41403501 Ryegrass Lolium perenne

96 VV >2.0 2.0 41403503

96 SE 0.211 <0.211 41403501 Corn Zea mays
96 VV 1.09 0.5 41403503

96 SE 0.118 <0.118 41403501 Onion Allium cepa

96 VV 12.33 2.0 41403503

SE: seedling emergence VV: vegetative vigor

EC 25 : Effective concentration for 25% reduc tion in emergence or growth measures

NOAEL: no observed adverse effect level

Toxicity to Aquatic Animals

Freshwater Fish Acute Toxicity

The results for available acute toxici ty testing with freshwater fish ( Table 10 ) indicate that quinclorac is slightly toxic to fish on an acute basis. The guideline requirement (72-1) is fulfilled. The bluegill sunfish LC 50 of 31.6 mg/L is used as the acute freshwater toxicity endpoint for the risk assessment.

Table 10 Freshwater Fish Acute Toxicity Data

Species % Active Ingredient LC 50 (confidence limit) (mg/L) MRID No. Classification

Bluegill sunfish Lepomis macrochirus 96 31.6 (26.7-39.6) 41063555 acceptable36 Rainbow trout Oncorhynchus mykiss 96 >83.5 (no mortality at highest dose tested) 41063548 acceptable

LC 50 : Lethal concentration to 50% of test population

NOAEC: No observed adverse effect concentration

Freshwater Fish Toxicity from Chronic Exposure

The following table summarizes the available fr eshwater fish toxicity data from chronic

exposure.

Table 11 Freshwater Fish Chronic Toxi city Data (Early Life Stage Study)

Species % Active Ingredient LOAEC (mg/L) NOAEC (mg/L) MRID No. Classification

Fathead minnow Pimephales promelas technical 31 (larval growth) 16 44084502 acceptable

LOAEC: Lowest observed ad verse effect concentration

NOAEC: No observed adve rse effect concentration

Freshwater Invertebrate Acute Toxicity

Results of invertebrate toxicity testing are listed in Table 12 . The results indicate that quinclorac is slightly toxic to aquatic invertebrates on an acute basis. The Daphnia magna EC 50 of 29.8 mg/L serves as the freshwater invertebrate toxi city endpoint for risk a ssessment. A freshwater aquatic invertebrate toxicity test using the techni cal grade of the active ingredient is required to assess the toxicity of a pesticide to freshwater invertebrates. Results of invertebrate toxicity testing are listed in the table be low. The results indicate that quinclorac is slightly toxic to aquatic invertebrates on an acute basis. Th e guideline requirement (72-2) is fulfilled. Quinclorac was conducted on a formulated product (q uinclorac plus surfacta nt) instead of TGAI. Therefore, use of the available acute data as the toxicity endp oint for all freshwater systems represents an uncertainty.

Table 12 Freshwater Invertebrate Acute Toxicity Data

Species % Active Ingredient EC 50 (confidence limit) (mg/L) MRID No. Classification

Daphnia magna 96 29.8 (23.8-42.4) 41063556 acceptable37 EC 50 : Effective concentration to 50% of test population

NOAEC: No observed adverse effect concentration Freshwater Invertebrate Toxi city from Chronic Exposure

Data for freshwater invertebrate chronic toxicity are listed in Table 13 . The guideline requirement (72-4) is fulfilled.38 The Daphnia magna 21-day NOAEC of 110 mg/L is used as the freshwater invertebrate toxicity endpoint for chronic exposure. It should be noted that the 21-day NOAEC unexpectedly exceeds

the 48-hour EC 50 for the same species. This observation is likely the result of differences in test water conditions, or as the result of surfactant use in the acute toxicity test. As quinclorac is an acid subject to dissociation in wa ter, differences in water hardne ss may influence the toxicity of the compound. The available data suggest th at quinclorac is more toxic to freshwater invertebrates in soft water (48-hour LC 50 = 28.9 mg/l in water 40-48 mg CaCO 3 /L) compared to harder water (21-day NOAEC 110 mg/l in water >150 mg CaCO 3 /L). An alternative explanation for the disparate toxicity results may be the pr esence of surfactant in th e acute test, whereas no

surfactant is evident for the chronic test. The use of the available 21-day chronic data as the toxicity endpoint for all freshwater systems represents an uncertainty.

Table 13 Freshwater Invertebrate Chronic Toxicity Data (21-day life cycle test)

Species % Active Ingredient LOAEC (mg/L) NOAEC (mg/L) MRID No. Classification

Daphnia magna technical >110 110 44129202 acceptable

LOAEC: Lowest observed ad verse effect concentration

NOAEC: No observed adve rse effect concentration

Estuarine and Marine Animal Acute Toxicity

Table 14 summarizes the data available for quinclorac effects on estuarine and marine animals. For the purposes of this risk a ssessment, the sheepshead minnow LC 50 of > 94.4 mg/L will be used as the acute toxicity threshold for estuar ine/marine fish and the mysid EC50 of 69.4 will

serve as the threshold for estuarine/marine invertebrates.

Table 14 Estuarine and Marine Animal Acute Toxicity Data

Species % Active Ingredient EC 50 /LC 50 (confidence limit) (mg/L) MRID No. Classification

Sheepshead minnow Cyprinodon variegatus 96 >94.4 (no mortality at highest dose) 41063549 core

Quahog clam

Mercenaria mercenaria 96 >96.1 (26% reduction in

number of normal larvae at highest dose) 41063552 core

Mysid Mysidopsis bahia 96 69.4 (50.4-118) 41063553 core

Blue crab 96 >94.4 41063551 supplemental*39 Callinectes sapidus (no mortality at highest dose)

LC 50 : Lethal concentration to 50% of test population

EC 50 : Effective concentration to 50% of test population

NOAEC: No observed adverse effect concentration *not listed acceptable test species

Estuarine and Marine Animal Toxicity from Chronic Exposure

No data are available for the toxicity of quinc lorac to estuarine and marine animals following chronic exposures.

Aquatic Plant Toxicity

Table 15 summarizes the available aquatic plant toxicity data for quinclorac

Table 15 Aquatic Plant Toxicity Data

Species % Active Ingredient EC 50 (mg/L) NOAEC (mg/L) MRID No. Classification

Freshwater diatom Navicula pelliculosa 96 >0.5 0.5 41063574

Green alga

Selenastrum capricornutum 96 >0.5 0.5 41063574

Marine diatom

Skeletonema

costatum 96 >0.5 0.5 41063574

Duckweed Lemna gibba 96 >0.5 0.5 41063574

Bluegreen algaAnabaena flosaquae 96 >0.5 0.5 41063574 acceptable

EC 50 : Effective concentration for 50% inhibition

NOAEC: No observed adverse effect concentration40 11.3. Preliminary Identification of Data Gaps for Fate and Ecological Assessment

Table 16 identifies fate and ecological studies which are missing or are not acceptable, and may be requested to assess risk to the environment:

Table 16 Preliminary Identification of Da ta Gaps for Fate and Ecological Assessment

Fate and Ecological

Taxa studies Description of study Projected status of data

gap Basis for decision

Chronic freshwater invertebrate Chronic freshwater invertebrate NOAEC value was greater than

the acute LD50 value for freshwater aquatic invertebrates Study requested A new study is requested due to

uncertainties with the NOAEC value which is greater than the

acute LD50 value for freshwater aquatic invertebrates.

In addition, this study will be

used to estimate chronic

estuarine marine invertebrate toxicity

Acute freshwater invertebrate Acute freshwater invertebrate study used a surfactant which it

is uncertain that this surfactant

effected the results of the toxicity test Study requested A new study is requested due to

uncertainties with the LD 50 value

which is less than the chronic

NOAEC value for freshwater aquatic invertebrates. In addition, this study was based on a formulated product (quinclorac and surfactant).

This study will be used to

estimate chronic estuarine marine invertebrate toxicity

Estuarine/marine fish Chronic study for

estuarine/marine fish was not

submitted Study not requested Acute to chronic ratios will be sufficient to not request study

Estuarine/marine invertebrate Chronic study for

estuarine/marine invertebrate

was not submitted Study not requested Acute to chronic ratios will be sufficient to not request study pending a chronic freshwater invertebrate daphnia magna study based on TGAI .41 Data on the degradates (BH514- 1 and BH 514 2-OH; >10% applied)) and one minor (BH514- HMe-ester; 8% applied) to determine risks to groundwater The registrant claimed that studies performed later between 1989 and 1990 in FL, WI, and

NY showed no movement of quinclorac degradates below

surface levels Studies requested The degradates (BH514-1 and BH 514 2-OH; >10% applied))and one minor (BH514-HMeester; 8% applied) studies have not yet been received nor reviewed by EFED. Until these studies which were performed 1989-1990 are submitted, reviewed, and deemed acceptable by the Agency, the above

mentioned metabolites are considered potential contaminants of groundwater

resources.

Foliar dissipation residue data Fo liar dissipation data studies or

related data were not available Study not requested Acute and chronic mammal

exceedences did not occur with

LD50 and NOAEC values. Acute

avian LOCs occurred with the

non-definitive LD50 of >1900 mg/kg-bw. Fate studies indicate that half-lives may be greater than one year.

Therefore,A default foliar dissipation rate of 35 days will be used in the modeling in place of the data if study is not

submitted.

Small scale prospective groundwater contamination study Small scale prospective groundwater contamination study for the quinclorac under the expected conditions of the currently registered crops. Study requested Based on the environmental persistence of quinclorac, its potential to enter groundwater as modeled by SCI-GROW and

indicated in terrestrial field studies, the potential forgroundwater impacts to nontarget crops via contaminated groundwater a small scale prospective groundwater a contamination study for the compound under the expected

conditions of use in wheat and sorghum is requested

.

12. OPEN LITERATURE

Previous assessments did not include open lite rature data as identif ied by ORD, MED ECOTOX literature search program.

13. NEW ASSESSMENT DECISION

EFED needs additional data (or will apply alte rnate effects assumptions) and would need to conduct new assessments for all registered out door uses. The new assessments are needed because of the following:42 (a) Some uses and application type scenar ios were not assessed for ecological risk or

did not include current terrestrial or aquatic models.

(b) Open literature data, as identified by ORD, MED ECOTOX literature search program, were not included in previous assessments.

(dc) A new drinking water asse ssment needs to be completed based on a 14 day interval and aerial applications.

14. SUMMARY OF RISK

Summary of risks identified from previo us assessments and anticipated risks for maximum use rate application scenarios.

Estimated LOC exceedences for are summarized in Table 17 below. The risk conclusions are based on previously conducted risk assessments and anticipated exceedences for maximum use rates. The most recent comprehensive risk assessment was conducted on wheat and sorghum (1999). The most recent EUP was conducted on a quatic weed control in impounded waters (2007). The label maximum single application rate s for quinclorac: (1) wh eat and sorghum with

a maximum seasonal rate of 0.75 lb ai /acre (2 applications @ 0.375lb ai/A, intervals were not included in terrestrial RQ calculations); (2) aqua tic weed control with a maximum seasonal rate

of 3.0 lb ai /acre. Acute dose based for avian exposure to quinclorac exceeded the LOCs with RQs ranging from 0.12- 0.83 for the both of the a bove application scenarios. Terrestrial plant RQs exceeded the LOCs for the wheat, sorghum a nd aquatic weed control application scenarios with RQs ranging 1 to 40.

Nonvascular and vascular plants exceeded the LO Cs for the aquatic weed control scenario with RQs exceedences of 1.0. LOCs were exceeded for acute mammalian exposure with the maximum RQ of 0.14 for aquatic weed control scenarios. Chronic LOCs were exceeded for mammals and birds for the aquatic weed cont rol scenario with a maximum RQs of 1.95 (mammals) and 1.4 (birds).

Anticipated LOCs are based on the maximum use a nd application rate for quinclorac for turf at 1.50 lb ai/A (2 applications@ 0.75 lb ai/A an d 14 day intervals). Antic ipated LOC exceedences

from the above maximum use rate are for acute bird s (RQs 0.16- 0.37) and acute terrestrial plants (RQs 2.33- 95.63) for monocots and dicots. Th e acute avian LOC exceedence was based on the

non-definitive LD 50 value of >1900 mg/kg-bw. It is necessary that these exceedences derived

from the non-definitive LD 50 value of >1900 will be characterize d with additional data in future

assessments. No chronic avian LOC exceedences occurred with higher application rates.43 Aquatic EECs for the maximum application rates for labeled crops and additional GENEEC scenarios need to be determined. However, no acute or chronic exceeden ces are anticipated for aquatic fish or invertebrates. Uncertainty exists for chronic risks to estuarine marine

invertebrates until further data is submitted. Chr onic risks to estuarine marine fish will be

estimated from acute to chronic ratios. LOC exceedences for aquatic plants based on direct application to impounded waters result in RQs of 1.0.

Table 17 LOC Exceedences from Use on Wheat, Sorghum, Turf and Aquatic weed control.

Use Endpoint Birds Mammals Terr.

Plants Insect

s FW

fish SW

Fish FW

Inverts SW

Inverts Aquatic

Plants

Acute 9 based

on nondefinitive

value 9 (listed

and

nonliste d) Turf

1.50 lb ai/A

per season 2application s @0.75 per app, 14 day interval) Reproductive

Acute 9 based

on nondefinitive

value 9 (listed

and

nonliste d) Wheat and sorghum

0.75lb ai/A

per season 1 Reproductive

Acute 9 based

on nondefinitive

value 9 9 (listed

and

nonliste d) 9 (listed) Aquatic

weed control

3 lbs

a.i./season 1,2

Reproductive 9 9

1 All risk conclusions are based on prev iously conducted risk assessments De gradate toxicity was not

included.

2 This EUP was based on aquatic weed control applied at 3lbs ai/season to reach a water concentration of 0.5mg/L

9 Risk is anticipated to be > any of the Agency’s LOC

Blank cells indicate no LOC exceedences

Aquatic Organisms

Based on the (GENEEC) modeling, the 1999 risk assessment on turf showed no acute LOC exceedence for aquatic organisms. The highest modeled application rate scenario for the above crops was turf, which was based on 2 ground applicat ions at a single rate of 0.375 lb ai/acre. The peak EEC is selected to represent exposures for acute effect risks. The 56-day and 21-day average EECs serve as the exposures for chronic e ffects to fish and invertebrates, respectively.

Tables 18 to 22 summarizes the quinclorac RQs, EECs ((peak), (21-day), (56-day)) and the toxicity data used in the 1999 assessment on turf w ith ground and aerial app lications. No acute

or chronic LOCs were exceeded for the e xposure scenarios assessed. There are no44 estuarine/marine organism toxicity data from ch ronic exposures available for use in calculating chronic risk quotients for these organisms. Ho wever, the similar acute sensitivities of these organisms to freshwater fish and invertebrates, coupled with the very lo w chronic risk quotients calculated for freshwater organisms; suggests that chronic risk concerns for estuarine and marine fish and invertebrates are likely to be minimal.

Table 18 Acute and Chronic Risk Quotients for Freshwater Fish

Product 1 / Application

Method Peak

EEC (μg/L) LC 50 (μg/L) Acute RQ (Peak

EEC/LC 50 ) 56-day

EEC (μg/L) NOAEC (μg/L) Chronic RQ (56-d EEC/NOAEC)

40.28 31,600 0.0013 40.17 16,000 0.0025 Paramount TM /Aerial 90 and 14-day

intervals 40.28 31,600 0.0013 40.17 16,000 0.0025

40.20 31,600 0.0013 40.10 16,000 0.0025 Paramount TM / Ground Spray 90 and 14-day

intervals 40.20 31,600 0.0013 40.10 16,000 0.0025

Paramount TM BW/ Aerial 1 application 13.16 31,600 0.0004 13.11 16,000 0.0008

Paramount TM BW/ Ground Spray 1 application 13.13 31,600 0.0004 12.10 16,000 0.0008

1 Risks for Paramount TM BW are for the quinclorac com ponent alone, no assessment ha s been performed for the
2,4-D component of this product

.

Table 19 Acute and Chronic Risk Quotients for Freshwater Invertebrates

Product 1 / Application

Method Peak

EEC (μg/L) LC 50 (μg/L) Acute RQ (Peak

EEC/LC 50 ) 21-day

EEC (μg/L) NOAEC (μg/L) Chronic RQ (21-d EEC/NOAEC)

40.28 29,800 0.0014 40.23 110,000 0.0004 Paramount TM /Aerial 90 and 14-day

intevals 40.28 29,800 0.0014 40.23 110,000 0.0004

40.20 29,800 0.0013 40.16 110,000 0.0004 Paramount TM / Ground Spray 90 and 14 day

intervals 40.20 29,800 0.0013 40.16 110,000 0.0004

Paramount TM BW/

Aerial 13.16 29,800 0.0004 13.14 110,000 0.000145 Paramount TM BW/ Ground Spray 13.13 29,800 0.0004 13.12 110,000 0.0001

1 Risks for Paramount TM BW are for the quinclorac com ponent alone, no assessment ha s been performed for the
2,4-D component of this product

.

Table 20 Acute and Chronic Risk Quotients for Estuarine/Marine Fish

Product 1 / Application

Method Peak

EEC (μg/L) LC 50 (μg/L) Acute RQ (Peak

EEC/LC 50 ) 56-day

EEC (μg/L) NOAEC (μg/L) Chronic RQ (56-d EEC/NOAEC) 2

40.28 >94,400 <0.0004 40.17 no data

-- Paramount TM /Aerial 90 and 14-day intervals 40.28 >94,400 <0.0004 40.17 no data

--

40.20 >94,400 <0.0004 40.10 no data

-- Paramount TM / Ground Spray 90 and 14-day intervals 40.20 >94,400 <0.0004 40.10 no data

--

Paramount TM BW/

Aerial 13.16 >94,400 <0.0001 13.11 no data

--

Paramount TM BW/ Ground Spray 13.13 >94,400 <0.0001 12.10 no data

--

1 Risks for Paramount TM BW are for the quinclorac com ponent alone, no assessment ha s been performed for the
2,4-D component of this product

. 2 -- lack of toxicity data precludes calculation of quotient

Table 21 Acute and Chronic Risk Quotie nts for Estuarine/Marine Invertebrates

Product 1 / Application

Method Peak

EEC (μg/L) LC 50 (μg/L) Acute RQ (Peak

EEC/LC 50 ) 21-day

EEC (μg/L) NOAEC (μg/L) Chronic RQ (21-d EEC/NOAEC) 2

40.28 69,400 0.0006 40.23 no data

-- Paramount TM /Aerial 90 and 14-day intervals 40.28 69,400 0.0006 40.23 no data

--

40.20 69,400 0.0006 40.16 no data

-- Paramount TM / Ground Spray 90 and 14-day intervals 40.20 69,400 0.0006 40.16 no data

--

Paramount TM BW/

Aerial 13.16 69,400 0.0002 13.14 no data

--

Paramount TM BW/ Ground Spray 13.13 69,400 0.0002 13.12 no data

--

1 Risks for Paramount TM BW are for the quinclorac com ponent alone, no assessment ha s been performed for the
2,4-D component of this product

. 2 -- lack of toxicity data precludes calculation of quotient46 Table 22 Aquatic Plant Risk Quotients

Product 1 / Application

Method Peak

EEC (μg/L) Alga

EC 50 (μg/L) Lemna gibba

EC 50 (μg/L) Lemna gibba

NOAEC

(μg/L) Algal RQ 2 Acute Aquatic

Vascular Plant RQ 3 Endangered Aquatic Plant RQ 4

40.28 >500 >500 500 <0.081 <0.081 0.0806 Paramount TM /Aerial 90 and 14-day intervals 40.28 >500 >500 500 <0.081 <0.081 0.0806

40.20 >500 >500 500 <0.080 <0.080 0.0804 Paramount TM / Ground Spray 90 and 14-day intervals 40.20 >500 >500 500 <0.080 <0.080 0.0804

Paramount TM BW/

Aerial 13.16 >500 >500 500 <0.026 <0.026 0.0263

Paramount TM BW/ Ground Spray 13.13 >500 >500 500 <0.026 <0.026 0.0263

1 Risks for Paramount TM BW are for the quinclorac com ponent alone, no assessment ha s been performed for the
2,4-D component of this product

. 2 EEC/alga EC 50 3 EEC/ Lemna gibba EC 50 4 EEC/ Lemna gibba NOAEC

Terrestrial Organisms Risk Assessment for Nontarget Terrestrial Animals

Avian Acute and Chronic Risks

The acute and chronic risk quotients for broadcas t applications of quinclorac formulations are

listed in Tables 23 and 24 based on the 1999 risk assessment fo r a single seas onal application rate of 0.25 lb ai/A and 0.75 lb ai/A . No levels of concern (LOCs) are exceeded under the exposure scenarios assessed.47 Table 23 Avian Acute Risk Quotients for Si ngle Application of Quinclorac Products (Aerial and Ground Spray) Based on a North ern Bobwhite Quail LC50 of >5000 mg/kgdiet

Product 1 Application

Rate (lbs ai/A) Food Items Maximum EEC (mg/kg-diet) LC 50 (mg/kgdiet) Acute RQ (EEC/LC 50 )

Short

grass 180 >5000 <0.036

Tall

grass 82.5 >5000 <0.017

Broadleaf plants/Insects 101.3 >5000 <0.020 Paramount TM 0.75

per season

Seeds 11.3 >5000 <0.002

Short

grass 60.0 >5000 <0.012

Tall

grass 27.5 >5000 <0.006

Broadleaf plants/Insects 33.8 >5000 <0.007 Paramount TM DW 0.25

per season

Seeds 3.8 >5000 <0.001

1 Risks for Paramount TM BW are for the quinclorac com ponent alone, no assessment ha s been performed for the
2,4-D component of this product

.48 Table 24 Avian Chronic Risk Quotients for Single Application of Quinclorac Products (Aerial and Ground Spray Based on a Northe rn Bobwhite Quail NOAEC of 500 mg/kgdiet)

Product 1 Application

Rate (lbs ai/A) Food Items Maximum

EEC (mg/kg-diet) NOAEC (mg/kg-diet) Chronic RQ (EEC/NOAEC)

Short

grass 180 500 0.36

Tall

grass 82.5 500 0.17

Broadleaf plants/Insects 101.3 500 0.20 Paramount TM 0.75 per

season

Seeds 11.3 500 0.02

Short

grass 60.0 500 0.12

Tall

grass 27.5 500 0.06

Broadleaf plants/Insects 33.8 500 0.07 Paramount TM BW 0.25 per

season

Seeds 3.8 500 0.01

1 Risks for Paramount TM BW are for the quinclorac com ponent alone, no assessment ha s been performed for the
2,4-D component of this product

.

Mammalian Acute and Chronic Risks

Mammalian acute risk quotients were calculated using the daily oral dose estimates for a 15 g mammal consuming 95% of its bodyweight as diet and the LD50 for laboratory rats. The results

of these calculations are expressed in terms of LD 50 s per day. Table 25 summarizes the results of these risk quotient calculations. None of the ac ute risk quotient results exceed EFED levels of

concern.

Mammalian chronic risk quotients were calculated using the daily oral estimates for the same 15 g mammal and the daily oral dose correspondi ng to the NOAEL for reproduction effects in laboratory rats. Table 26 summarizes the results of these risk quotients calculations based on the 1999 assessment. In all cases, except for consum ption of short grass (RQ = 1.07), the EFED

level of concern was not exceeded.49 Table 25 Mammalian Acute Risk Quotients for Application of Quinclorac Products (Aerial and Ground Spray Based on a La boratory Rat LD50 of 2190 mg/kg-bw

Product 1 Application

Rate (lbs ai/A) Food Items Daily Oral Dose (mg/kg-bw/day) LD 50 (mg/kg-bw) Acute RQ
(LD50/day or

Dose/LD 50 )

Short

grass 171.6 2190 0.08

Tall

grass 78.7 2190 0.04

Broadleaf plants/Insects 96.5 2190 0.04 Paramount TM 0.75 per

season

Seeds 10.7 2190 0.005

Short

grass 57.2 2190 0.03

Tall

grass 26.2 2190 0.01

Broadleaf plants/Insects 32.2 2190 0.01 Paramount TM DW 0.25 per

season

Seeds 3.6 2190 0.002

1 Risks for Paramount TM BW are for the quinclorac com ponent alone, no assessment ha s been performed for the
2,4-D component of this product

.50 Table 26 Mammalian Chronic (Reproducti on) Risk Quotients for Application of Quinclorac Products (Aerial and Ground Spray Based on a Laboratory Rat NOAEL of 160 mg/kg-bw/day

Product 1 Application

Rate (lbs ai/A) Food Items Daily Oral Dose (mg/kg-bw/day) NOAEL (mg/kg-bw/day) RQ (Dose/NOA EL)

Short

grass 171.6 160 1.07

Tall

grass 78.7 160 0.49

Broadleaf plants/Insects 96.5 160 0.60 Paramount TM 0.75 per

season

Seeds 10.7 160 0.067

Short

grass 57.2 160 0.36

Tall

grass 26.2 160 0.16

Broadleaf plants/Insects 32.2 160 0.20 Paramount TM BW 0.25 per

season

Seeds 3.6 160 0.023

1 Risks for Paramount TM BW are for the quinclorac com ponent alone, no assessment ha s been performed for the
2,4-D component of this product

.

Risks to Beneficial Insects

Currently, EFED has no procedure for assessing risk to nontarget insects. However, the results of acceptable toxicity studies are used for reco mmending appropriate label precautions. The relatively non-toxic nature of quinclorac with respect to hone ybees suggests no concern that quinclorac will directly impact beneficial insects.

15. RESIDUES OF QUINCLORAC IN WATER AND THE TERRESTRIAL

ENVIRONMENT

DRINKING WATER RESIDUE PROFILE

The Agency does not have monitoring data available to perform a quantitative drinking water risk assessment for quinclorac at this time

A Tier II screening-level drinking water assessment for quinclorac (3,7-dichloro-8- quinolinecarboxylic acid , BAS 514-H was provided in support of the new proposed uses of this

herbicide to control br oadleaf and grass weeds on resident ial/commercial turf grasses and on other turf grasses (picnic grounds , athletic field, and sod farms) (see September 13, 2007,51 Estimated Drinking Water Assessment for Quinclor ac (3,7-dichloro-8-quinolinecarboxylic acid, CAS# 84087-01-4) Use on Turfgrasses DPBarcode: 341487)

EFED believes that quinclorac has the potential for movement into ground water. Furthermore, since quinclorac is not tightly bound to soils, it co uld be available to run off in surface water as well as by erosion to surface waters. Tables 27 and 28 list the EDWCs of quinclorac residues in surface and ground water, respectively, as repo rted in the aforementioned drinking water

assessment. These concentrations are based on the current environmental fate data for quinclorac, the maximum use rate from register ed and proposed uses (Drive 75DF Herbicide label turf use, 2 to 3 applications of 0.25 – 0.75 lb ai/A/ appl at 21-day interval, not to exceed 1.5 lb ai/A per year) and EFED aquatic models (PRZM/EXAMS for surface water and SCI-GROW for ground water

.

Quinclorac major degradation products such as BH 514-1 and BH 514 2-OH were not considered in this assessment. Although these degradates were detected in the laborat ory studies, they seem to be intermediate degradates (see Environmen tal Fate section), and were not found in the terrestrial field dissipation studies at any significant levels (>10% of total applied). Furthermore, since quinclorac is persistent a nd mobile, it is expected to be the predominant residue in ground
and surface waters.

Table 27 – Surface Water DWECs for Quinclorac use on Turfgrasses, ground application

Surface Water EWDCs (μg/L)

Scenario 1 in 10 year annual peak (acute) 1 in 10 year annual

mean (chronic) 30 year annual mean (cancer)

PCA / CAF 1.00* 0.82** 1.00 0.82 1.00 0.82 0.5 lb ai/A, 3 appl, 21 days apart PA Turf – pre emergence

PA Turf – post emergence

FL Turf – pre-emergence

FL Turf – post emergence

0.75 lb ai/A, 2 appl, 21 days apart PA Turf – post emergence

FL Turf – post emergence 17.5

21.2

17.9

22.9

22.5

21.4 14.3

17.4

14.7

18.8

18.5

17.5 12.3

14.5

10.7

12.7

14.2

11.6 10.1

11.9

8.8

10.4

11.6

9.5 8.7

10.3

6.3

7.1

9.9

6.9 7.1

8.4

5.2

5.8

8.1

5.7

*Results with PCA of 1 can be used for other turf us e, such as picnic grounds, athletic fields, sod farms,

... ** Results adjusted with CAF of 0.82 repr esents the maximum percent treated on turf, residential and commercial use . This assumes four houses

of 2000ft 2 each per acre and does not take into acc ount driveway, sidewalk, or porches, ...

Note that the EDWCs were estimated for both pre and post emergence uses for the 0.5 lb ai/A applications. The differences between the two sets of data result from the method of application (soil applied vs. foliar applied) and the application dates. Only post emerge nce uses are allowed for the 0.75 lb ai/A applications.52 Table 28 - Ground Water EDWCs for Quinclorac use on Turfgrasses (3 applications of 0.5 lb ai/A/application)

Ground Water EDWCs (μg/L) (3 appl of 0.5 lb ai/A/appl)

Ground Water EDWCs (μg/L) (2 appl of 0.75 lb ai/A/appl) 29.0

28.9

The groundwater concentrations generated by SCI-GROW are based on the largest 90-day average recorded during the sampling period. Since there is relatively little temporal variation in groundwater concentrations compared to surface water, the concentration of 29μg/L can be considered as both the

acute and chronic values.

Although current uses also include aerial applications with an assumed shorter re-application interval (14 days) on certain crops (sorghum, wheat, non agricu ltural rights of way/ fence row/ hedgerows, agricultural fallowland/idleland, grasses grown for seed ), it is not expected that the EDWCs from these crops will exceed those reported from turf use as listed in above Tables 28 and 29. Granular applications do not need to be incorporated in the drinking water assessment because the application rates are less than ground and aerial spray applications.

Chemical structures for quinclorac are summarized in Table 29

.53 Table 29 Chemical name and structure of quincl orac and its degradates BH514-1 and

BH5142-OH

Common Name Chemical Structure

Quinclorac

BH514-1

BH5142-OH N Cl

Cl CO 2 H

N CO 2 H

N CO 2 H

OH

Cl54 Table 30 list all the current registration s and EUPs based on BEAD information 2007.

Table 30 Current Registrations and EUPs for Quinclorac based on BEAD information (2007)

Registration # Name Status Company Name Percent

Active Ingredient

228-423 DQD SELECTIVE

HERBICIDE Conditionally Registered (06- Apr-2005) NUFARM AMERICAS

INC. 7.91

228-531 NUP 12D02

HERBICIDE Conditionally Registered (24- Aug-2007) NUFARM AMERICAS

INC. 8.25

239-2689 LAWN CRABGRASS

AND WEED KILLER Conditionally Registered (03- Sep-2004) THE ORTHO

BUSINESS GROUP 0.1

538-296 TURF BUILDER WITH

WEED CONTROL III Conditionally Registered (09- Dec-2002) SCOTTS COMPANY,

THE 0.52

1381-209 QUINCLORAC 75 DF Registered (11- Oct-2006) WINFIELD SOLUTIONS, LLC 75

2217-885 EH-1426 HERBICIDE Conditionally Registered (18- Jan-2006) PBI/GORDON CORP 3.49

2217-886 EH-1427 HERBICIDE Conditionally Registered (18- Jan-2006) PBI/GORDON CORP 5.69

2217-887 EH-1428 HERBICIDE Conditionally Registered (18- Jan-2006) PBI/GORDON CORP 0.121

2217-888 EH-1425 HERBICIDE Conditionally Registered (18- Jan-2006) PBI/GORDON CORP 8.38

2217-894 EH-1432 HERBICIDE Conditionally Registered (21- Apr-2006) PBI/GORDON CORP 1.61

2217-896 EH-1437 HERBICIDE Conditionally Registered (25- Aug-2006) PBI/GORDON CORP 2.13

2217-901 EH-1434 HERBICIDE Conditionally Registered (30- Jan-2007) PBI/GORDON CORP 5.65

2217-906 EH-1449 HERBICIDE Conditionally Registered (27- Aug-2007) PBI/GORDON CORP 0.10455 7969-93 FACET 50 WP Conditionally Registered (13- Oct-1992) BASF CORPORATION 50

7969-109 QUINCLORAC

MANUFACTURING

USE PRODUCT Conditionally Registered (28- Oct-1992) BASF CORPORATION 98

7969-113 FACET 75 DF

HERBICIDE Registered (09- Nov-1994) BASF CORPORATION 75

7969-130 DRIVE 75 DF

HERBICIDE Conditionally Registered (09- Nov-1998) BASF CORPORATION 75

7969-152 PARAMOUNT BW

HERBICIDE Conditionally Registered (04- Jun-1999) BASF CORPORATION 15

7969-158 FACET GR

HERBICIDE 46 Conditionally Registered (27- Apr-1998) BASF CORPORATION 1.5

7969-172 DRIVE 75

MANUFACTURERS

CONCENTRATE Conditionally Registered (10- Dec-1998) BASF CORPORATION 75

7969-222 CLEARPATH

HERBICIDE Registered (12- Jul-2004) BASF CORPORATION 61.98

34704-920 QUINCLORAC 75DF

HERBICIDE Conditionally Registered (03- Mar-2006) LOVELAND PRODUCTS, INC. 75

42750-85 QUINCLORAC

TECHNICAL Conditionally Registered (10- Oct-2005) ALBAUGH INC 99

42750-88 QUINCLORAC 75DF

AG Conditionally Registered (10- Oct-2005) ALBAUGH INC 75

42750-90 QUINCLORAC 75DF

SP Conditionally Registered (10- Oct-2005) ALBAUGH INC 75

42750-131 QUINCLORAC 75

SWF Conditionally Registered (06- Feb-2006) ALBAUGH INC 75

71085-26 RICEPRO Registered (13- Mar-2007) RICECO LLC 2

73220-15 QUALI-PRO QUINCLORAC 75 Registered (02- Oct-2007) FARMSAVER.COM,

LLC 75

79676-22 QUINCLORAC G-PRO

75 DF Conditionally Registered (14- Dec-2005) GRO-PRO, LLC 7556 81927-21 ALLIGARE QUINCLORAC 75

WDG Registered (18- Oct-2007) ALLIGARE, LLC 75

AR070006 RICEPRO Under Review (07-May-2007) RICECO LLC 2

UT990003 FACET 75 DF

HERBICIDE Registered (20- Sep-1999) BASF CORPORATION 75

7969-EUP-25 Issued (20- Mar-1991) BASF CORPORATION 100

7969-EUP-27 Issued (14-Jan1991) BASF CORPORATION 50

7969-EUP-29 Issued (22- May-1991) BASF CORPORATION 50

7969-EUP-40 Issued (23- May-2007) BASF CORPORATION 75

98ND20 Issued (19-Sep1998) ND Dept. of Agriculture

98NE07 Issued (25-Jun1998) NE Department of Agriculture57 

### V. Human Health Effects Scoping Document

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460

OFFICE OF PREVENTION, PESTICIDES AND
TOXIC SUBSTANCES MEMORANDUM

Date: September 26, 2007

SUBJECT: Quinclorac (PC code 128974). Human Health Risk Problem Formulation Document in Support of Registration Review. DP Barcode 344486.

FROM: Yan Donovan, Risk Assessor Health Effects Division (7509P) Office of Pesticide Programs

THRU: Ray Kent, Branch Chief Susan Hummel, Senor Scientist Reregistration Action Branch 4 Health Effects Division (7509P) Office of Pesticide Programs

TO: Sherrie Kinard Chemical Review Manager Special Review and Rere gistration Division (7508P) Office of Pesticide Programs

Executive Summary

Attached is Health Effects Division’s (HED) hu man health risk assessment status update for quinclorac as part of the Regi stration Review process. Quinclorac is a systemic herbicide currently registered for use on rice, sorghum, an d wheat. It is also registered for use on residential lawns, ornamentals, and turf grass. The most recent comprehensive risk assessment for quinclorac was conducted in association with the establishment of import tolerance on barley (September, 2007). The toxic effects being re gulated are developmental effects such as increased resorptions and post-implantation loss, decreased number of live fetuses, and reduced fetal body weight. Chronic effects include decreased body weights. Based on the 2005 Guidelines for Carcinogen Risk Assessment, quinclorac was tentatively classified as "Not likely58 to be carcinogenic to humans" si nce only benign tumors were seen in only one sex and in one species. Aggregate risk assessments included dietary exposure (food + water) and residential post-application exposure from use on grass. Riskestimates were based on conservative, healthprotective assumptions and the resu lting aggregate risk estimates are not of concern. Neither residential handler nor occupati onal risks were assessed.

HED’s problem formulation conclusi ons are: 1) The toxicology endpoi nt selections are adequate. However, the toxicology database for quinclorac is incomplete at this time. A 90-day inhalation toxicity study in the rat is requi red to assess inhalation exposure fr om spray uses. 2) The dietary exposure database is complete. However, the newly submitted aspirated grain fraction (AGF) studies on wheat and sorghum have not been revi ewed. A full review of these AGF studies is needed. AGF and livestock tolerances may need to be revised based on the review of the AGF studies. The drinking water assessm ent is adequate. The dietary exposure assessment (included food and water) is adequate. 3) The residential post application exposure assessment is adequate. However, no residential handler risks were assessed; therefore, a new residential handler assessment is needed for the Registration Review of quinclorac. 4) Aggregate risk assessment is adequate. 5) No occupational risk assessments have been conducted before. A new occupational assessment is required for Registration Review.59 Introduction

HED has evaluated the existing human health risk assessments for quinclorac to determine

whether sufficient data are available and whether a new human health risk assessment is needed to support Registration Review. HED has consid ered the most recent risk assessments for quinclorac (HED memo of 9/ 13/2007, M. Doherty, D325790, and HED memo of 12/15/98, M. Nelson, D238399), updates to its toxicity, exposure and usage databases, information available through HED and OPPIN database, literature sear ch, and current Agency science policies and risk assessment methods. Quinclorac is a persis tent and mobile, systemic herbicide currently registered for use on weed control in rice, sorghu m, and wheat. It is also registered for use on residential lawns, ornamentals, and turf grass. The mechanism of action of herbicidal effects is not completely understood. Perman ent tolerances are cu rrently established fo r parent quinclorac

per se in/on rice, sorghum, wheat, and livesto ck commodities [40 CF R 180.463]. Some quinclorac products also contain other active ingr edients such as 2,4-dichlorophenoxyacetic acid [2,4-D]. The problem formulation conducted in this review is for quinclorac only.

Chemical Identity

Table 1. Quinclorac Nomenclature

Chemical structure

Cl N OH O

Cl

Common name Quinclorac Empirical formula C 10 H 5 Cl 2 NO 2 Molecular weight 242.1

PC Code 128974 IUPAC name 3,7-dichloroqu inoline-8-carboxylic acid
CAS name 3,7-dichloro-8 -quinolinecarboxylic acid CAS registry number 84087-01-4

Hazard Identification/Toxicology

Quinclorac (technical grade material) has a low order of acute toxicity as demonstrated by classification into Toxicity Category III by the oral, dermal, and inhalation routes. The chemical is a mild eye irritant, is not a skin irritant, but was positive for dermal sensitization. Subchronic toxicity includes decreased body we ight gains, increased water in take, increased liver enzymes

and focal chronic inters titial nephritis. Chronic toxic eff ects include body weight decrement, increase in kidney and liver weights, and hydropic degeneration of the kidneys. At high doses, chronic toxicity also includes increased incidences of pancr eatic acinar cell hyperplasia and adenomas. Developmental toxicities include increased resorptions, post-implantation loss, decreased number of live fetuses, and reduced feta l body weight. These effects occurred at much60 higher dose than the maternal effects which demonstrated by increased mortality, decrease in food consumption and increase in water consumpti on, decreased body weight gain, clinical signs of reduced defecation, diarrhea, apathy, and poor general state. Because there is no evidence of neurotoxic effects, no acute, subchronic, or deve lopmental neurotoxicity studies are required.

Evaluated under the 2005 Guidelines for Ca rcinogen Risk Assessment, quinclorac was tentatively classified as "Not likely to be carci nogenic to humans" since only benign tumors were seen in only one sex and in one species. Th e chronic RfD would ade quately account for all chronic effects, including the observed adenomas , likely to result from exposure to quinclorac. The acute dietary endpoint was based on develo pmental toxicity, while the chronic dietary endpoint was based on decreased body weight in the 18-month carcinogenicity study. No data were available on the inhalation toxicity of quinc lorac. Inhalation endpoint was based maternal toxicity from the rabbit developmental study and assuming inhalation absorption of 100%.

The FQPA Safety Factor was reduced from 10X to 1X for infants and children based upon the fact that the toxicology databa se for quinclorac is complete and there is no indication of increased susceptibility of rat or rabbit fetuses to in utero and/or postnatal exposure in the developmental and reproductive toxicity data. A summary of the toxicological endpoint

decisions from the most recent human health risk assessment of quinclorac is given in Appendix

A.

Conclusions: The HED Registration Review problem formulation team has re-evaluated the above toxicity endpoints and dose response accordi ng to the current policies. HED concluded that the endpoint selections in the most recent risk assessment are adequate . A 28-day subchronic inhalation study is recommended.

Dietary Exposures

The residue of concern in food and wa ter was determined to be quinclorac per se . The estimated drinking water concentration (EDWC) from groun dwater (29 μg/L) was used in the dietary assessment as these are greater than the surface water values. Since there is relatively little temporal variation in groundwater concentrations compared to surface water, the concentration (29 ug/L) was used for both acute and chr onic exposure assessment. Acute and chronic aggregate dietary (food + drinki ng water) exposure were conducte d using the Dietary Exposure Evaluation Model DEEM-FCIDTM, Version 2.03 which use food consumption data from the U.S. Department of Agriculture’s Continuing Surveys of Food Intakes by Individuals (CSFII)

from 1994-1996 and 1998. Both the acute and chronic dietary assessment are based on tolerance-level residues for all agricultural co mmodities, assume 100% crop treated, use DEEM 7.81 default processing factors, and directly incorporate modeled quinclorac EDWCs.

The acute assessment provides a risk estimate of < 1% of the acute population-adjusted dose (aPAD) at the 95 th percentile of exposure for females 13-49 y ears of age. Risk estimates for the chronic assessment vary by populat ion group and range from < 1% of the chronic PAD (cPAD)

to 2% of the cPAD.

Conclusions: The residue chemistry database is complete with the newly submitted AGF

studies. These new studies have not been review ed. A review of these studies is needed. Existing AGF tolerance was previously determined by applying the maximum theoretical concentration factor (200X) to the proposed tole rance (6 ppm) on grain sorghum grain which is61 1200 ppm. The new AGF tolerance will likely be a lot lower based on the new AGF studies and as a result, the animal dietary burden will likely be lower, hence th e residues in meat and meat byproducts will likely be lower as well. Revisions to the exis ting AGF and livestock tolerances may be needed. The drinking water assessment is adequate. The dietary exposure assessment is also adequate. No new dietary assessment is needed.

Residential Exposure

Based on the registered use pattern, there are re sidential handler and resi dential post application exposure scenarios. Post-application incidental oral (hand-to-mouth, object-to-mouth, and soil ingestion) exposures were evaluated using the maximum application rates (0.0172 lb ai per 1000 sq ft). The combined MOE (5,000) is greater than 100 and, therefore, is not of concern to HED.

Conclusions: The post-application exposure assessments are adequate. However, no residential

handler assessment was conducted. A new residential handler assessment is needed for the Registration Review of quinclorac.

Aggregate

Aggregate risk assessments were conducted for acut e, chronic, and short-term. There is no risk

for concern.

Conclusions: HED problem formulation team concluded that the most recent aggregate risk assessment is adequate. No new aggregate risk assessment is needed for the Registration Review of quinclorac.

Occupational Exposure

There are occupational exposure scenarios based on the use patterns. However, no occupational

risk assessments have been conducted before. A new occupational assessment is required for the Registration Review once the inhalation endpoint is selected.

Incident Report

No incident report has been generated for quinclor ac. A new incident report is needed with the Registration Review.

Cumulative

Quinclorac has not been identified as a me mber of common mechanism group; therefore, accumulative assessment has not been conducted for quinclorac.

Human Studies

No human studies were used in either hazard or exposure assessment.

Codex MRLs62 No Codex or Mexico MRLs are reported. Th e U.S. tolerances on livestock fat and meat byproducts are not harmonized with Canada MRLs (s ee Appendix B for details). Future work is

needed to harmonize these tolerances.

Conclusions/Future Actions Needed

Below are the detailed actions needed in the future Registration Review for quinclorac:

Exposure

The 1998 risk assessment indicated the need for da ta on aspirated grain fractions as a data gap in the residue chemistry database, and s ubmission of such data should be made a condition of registration . Since then, residue data on wheat and sorghum aspirated grain fractions have been submitted but not been reviewed. They are:

45598703 Haughey, D.; Abdel-Baky, S.; Da ussin, S. (2000) Magnitude of BAS 514 H Residues in Wheat Aspirated Grain Fracti on: Lab Project Number: 2000/5187: 59553. Unpublished study prepared by BASF Corp. 61 p. {OPPTS 860.1500}.

45598704 Haughey, D.; Daussin, S. (2000) Ma gnitude of BAS 514 H Residues in Sorghum Aspirated Grain Fraction: Lab Project Numb er: 59552: 2000/5186. Unpublished study prepared by BASF Corp. 61 p. {OPPTS 860.1500}.

Tolerances on AGF and livestock commodities may need to be revised based on the review of

the above studies.

A residential handler assessment is needed.

Occupational Exposure and Risk A new occupational assessment is needed.

Incident Report A new incident report is needed.

Data Requirements

A 28-day subchronic inhalation study is recommended.

References

1) HED memo of 9/13/07, M. Doherty, D325790; 2) HED memo of 12/15/98, M. Nelson, D238399; 3) Bibliography for Quinclorac (OPPIN database).63 Appendix A

Summary of Toxicological Doses and Endpoints from the Most Recent Risk Assessment.

Exposure/

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

Level of

Concern for

Risk

Assessment Study and Toxicological Effects

Acute Dietary (General Population, including

Infants and Children) Not applicable. An endpoint for acute dietary exposure to the ge neral population was not selected because there was no available endpoint that was appr opriate for this scenario (effects observed in the available studies are presumed to require more than one exposure).

Acute Dietary (Females 13- 49 years of age) NOAEL (developmental) = 200 mg/kg/day UF A = 10x

UF H =10x FQPA SF= 1x Acute

NOAEL =

200 mg/kg/day

aPAD = 2.0 mg/kg/day Developmental toxicity study in rabbits Developmental toxicity LOAEL = 600 mg/kg/day based on increased early resorptions and postimplantation loss, decreased live fetuses, decreased fetal weight. These fetal effects are presumed to occur after a single dose.

Chronic Dietary (All Populations) NOAEL= 37.5 mg/kg/day UF A = 10x

UF H =10x FQPA SF= 1x Chronic

NOAEL =

37.5 mg/kg/day

cPAD =

0.38 mg/kg/day Dietary carcinogenicity study in mice LOAEL = 150 mg/kg/day based on decreased body weight.

Incidental

Oral ShortTerm (1-30 days) and

IntermediateTerm (1-6 months) NOAEL= 70 mg/kg/day UF A = 10x

UF H =10x FQPA SF= 1x Residential

LOC for

MOE = 100 Developmental toxicity study in rabbits. Maternal toxicity LOAEL = 200 mg/kg/day based on decreased maternal body weight gain and food consumption (and increased water consumption).

Dermal (all durations) Not applicable. A dermal endpoint was not selected because an appr opriate endpoint was not available (no dermal toxicity at limit dose of 1000 mg/kg/day in a 21-day dermal toxicity study).

Inhalation

Short-Term (1-30 days)

and

IntermediateTerm (1-6 months) NOAEL= 70 mg/kg/day [Inhalation absorption rate =
100% relative to oral absorption] UF A = 10x

UF H = 10x FQPA SF= 1x Residential

LOC for

MOE = 100 Developmental toxicity study in rabbits. Maternal toxicity LOAEL = 200 mg/kg/day based on decreased maternal body weight gain and food consumption (and increased water consumption). (Supported by subchronic and chronic dietary data on mice).

Inhalation Long-Term (>6 months) Not applicable. Long-term inhalation exposure is not anticipated under current use scenarios.64 Summary of Toxicological Doses and Endpoints from the Most Recent Risk Assessment.

Exposure/

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

Level of

Concern for

Risk

Assessment Study and Toxicological Effects

Cancer (oral, dermal, inhalation) Available carcinogenicity studies indicate that there was equivocal evidence of an increase in the incidence of pancreatic acinar cell adenomas in the male rat, but no treatment-associated increases in

tumors were observed in female rats or in mice. A quantification of cancer risk is not warranted because the chronic RfD of 0.4 mg/kg/day is approximately 1200-fold lower than the dose (487 mg/kg/day) that induced the benign pancreatic tu mors. Thus, the chronic RfD will adequately account for all chronic effects, including the obse rved adenomas, likely to result from expo sure to quinclorac. If quinclorac is evaluated under the current 2005 Guidelines for Carcinogen Risk Assessment, quinclorac will be classified as "Not Likely to be Carcinogenic to Humans" since only benign tumors were seen in only one sex and in one species. Point of Departure (POD) = A data point or an estimated point that is derived from observed dose-response data and used to mark the beginning of extrapolation to determine risk associated with lower environmentally relevant human exposures. NOAEL = no observed adverse effect level. LOAEL = lowest observed a dverse effect level. UF = uncertainty factor. UF A = extrapolation from animal to human (interspecies). UF H = potential variation in sensitivity among members of the human population (intraspecies). UF L = use of a LOAEL to extrapolate a

NOAEL. UF S = use of a short-term study for long-term risk assessment. UF DB = to account for the absence of key date (i.e., lack of a critical study). FQPA SF = FQPA Safe ty Factor. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. MOE = margin of exposure. LOC = level of concern. N/A = not applicable.65 Appendix B

Quinclorac

US Canada Mexico Codex

Residue Definition:
Quinclorac (3,7-dichloro-8-quinoline carboxylic acid)

40CFR180.463 3,7-dichloroquinolin8- carboxylic acid none none

Commodity Tolerance (ppm) /Maximum Residue Limit (mg/kg) Cattle, fat 0.7 0.05 Cattle, meat byproducts 1.5 0.05 Cattle, meat 0.05 0.05 Egg 0.05 0.05 Goat, fat 0.7 0.05 Goat, meat byproducts 1.5 0.05
Goat, meat 0.05 0.05 Grain, aspirated fractions 1200 - Hog, fat 0.7 0.05 Hog, meat byproducts 1.5 0.05 Hog, meat 0.05 0.05 Horse, fat 0.7 0.05 Horse, meat byproducts 1.5 0.05
Horse, meat 0.05 0.05

Milk 0.05 0.05 Poultry, fat 0.05 0.05 Poultry, meat byproducts 0.1 0.05 Poultry, meat 0.05 0.05 Rice, bran 15.0 - Rice, grain 5.0 5 Rice, straw 12.0 - Sheep, fat 0.7 0.05 Sheep, meat byproducts 1.5 0.05 Sheep, meat 0.05 0.05 Sorghum, grain, forage 3.0 - Sorghum, grain, grain 6.0 - Sorghum, grain, stover 1.0 - Wheat, forage 1.0 - Wheat, germ 0.75 - Wheat, grain 0.5 0.5 Wheat, hay 0.5 - Wheat , straw 0.1 - Barley 2.0 2.0