Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **1** of **32 UNITED STA** 

**TES ENVIRONMENTA L PROTECTION A** **GENCY WA** **SHINGTON, D.C. 20460 OFFICE OF**  **CHEMICAL SAFETY & POLUTTION**  **PREVENTION MEMORANDUM**  **Date:** 09/ 12 /20 1 2 **SUBJECT:** Quinclorac on Rhubarb and L ow Growing Berries (except Strawberry )
. Summary of Analy tical Chemistry

and Residue Data. Residue Chemistry

Considerations for Registration Review of Quinclorac and Quinclorac Dimethyl Amine
. **PC Code s**  **:** 0 28974 , 128974 **DP Barcode:** D397719 , 404569, 404912 **Decision No.:**  459055 and 468877 **Registration No. :**  42750
- 169 **Petition No.:** 1E7957 **Regulatory Action:** Section 3 Registration and Registration Review **Risk Assessment Type:** NA **Case No.:** 7222 **T XR No.:**  NA **CAS No.:** 84087
- 01
- 4 , 84087
- 48
- 9 **MRID No.:** 4869750 1 , 4869750 2 **40 CFR:** 180.463 From: Susan V. Hummel , Chemist

Gary Otakie, Chemist Risk Assessment Branch 4, Health Effects Division (7509P) Through: Thurston G .Morton , Chemist

Risk Assessment Branch 4, Health Effects Division (7509P) To: Sidney

Jackson and Barbara Madden, PM#5 RIMUERB, R egistration Division (7 505P ) Erik Kraft and Kable Davis, PM#25 Herbicide Branch, R egistration Div ision (7 505P ) Wilhelmina L ivingston , RM#60 Pesticide Reevaluation Division (7508P) **Executive Summary** Quinclorac [3, 7
- Dichloro
- 8
- quinolinecarboxylic acid] is a selective post
- emergent herbicide used for the control of various annual grasses and broad leaf weeds in barley , wheat, rice, sorghum and grasses grown for seed. Permanent tolerances have been established for residues of quincloracQuinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **2** of **32** per se in/on barley , rice, sorghum and wheat at levels ranging from 0.1 ppm in wheat straw to 1200 ppm in aspirate d grain fractions [40 CFR §180.463(a)]. Permanent tolerances have also been established for residues of quinclorac , per se, in/on livestock commodities at levels ranging from 0.05 to 1.5 ppm. Inaddition , the re is a tolerance for residues quinclorac on c ranberry in §180.463(b) , as a result of a Section 18 emergency exemption at 15 ppm. The Inter Regional Project No. 4 (IR
- 4) has submitted a request for tolerances and registration of quinclorac on low growing berries, except strawberries, subgroup 13
- 07H, and rhubarb. Tolerances were proposed for residues of quinclorac in low growing berries, except strawberries, subgroup 13
- 07H, at 1.1 ppm, and rhubarb at 0.4 ppm. A new phy sical form of quinclorac (EPA Reg. No. 7 9 69
- 272) ha s recently been registered : Drive XLR
- 8 (Reg. No 7969
- 272), Paramount LHerbicide (Reg. No. 7969
- 315 ) , Facet L Herbicide (EPA Reg. No. 7969
- 316 ) , and Quinclorac 1.5 DMA (Reg. No 42750
- 224 ) . These products are DMA (di m ethylamine) salt forms of quinclorac . These products were not propo sed for the new uses of quinclorac , proposed in the current petition , but are registered for use on rice and ornamental turf. The qualitative nature of quinclorac residues in plants wa s considered adequately understood for the currently

registered crops , based upon the metabolism studies on rice, sorghum, and wheat. Additional metabolism data are needed on a fruit commodity to support use on berries. Further metabolism data may

be needed if uses are further expanded. The qualitative nature of quinclor ac residues in livestock is also understood based upon the adequate goat and poultry met abolism studies. The Agency had concluded that parent is the only residue of concern in both plant and livestock commodities for purposes of the tolerance expression and risk assessment. However, the official enforcement method includes a methylation step, so the methyl ester of quinclorac is implicitly

included as a residue of concern. An adequate enforcement method is available for enforcing quinclorac tolerances on plants and livestock, a GC/ECD method that uses methylation with diazomethane. There are available FDA multi
- residue method ( MRM) testing data that indicate that quinclorac is completely recovered using Protocol B
. Adequate analy

tical methods are available f or determining residues of quinclorac , per se, in/on plant parts , an LC /MS/MS method (BASF Method A9708/1 )
. The validate d LOQ for quinclorac is 0.05 ppm
. However, this method would not determine the methyl ester of quinclora c, which is implicitly included in the residue of concern. Adequate cattle and poultry feeding studies are available and support the use of of quinclorac
. Adequate rotational crop studies are available and support the use of quinclorac
.Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **3** of **32 Regulatory Recommendations and Residue Chemistry Deficiencies**  **860.1200 Directions for Use.** 1. Cranberry

i s an aquatic crop, and as such, a label restriction is needed reg arding the use of tr eated rice and cranberry fields for aquaculture. Altern atively , the petitioner may determine residues in catfish and crayfish raised in treated fields and propose tolerances for these commodities , if necessary
. The label provided for Quinclorac/QuinStar 4
- L does not contain any restriction against aquaculture
. 2. For Registration Review, the PM must ensure that all labels for quinclorac on rice and cranberry contain a label restriction restricting the use of tr eated rice and cranberry fields for aquaculture
. **860.1300 Nature of the Residue in Plants** 3. While the me tabolism of quinclorac is adequately understood with regard to the currently registered uses, there are no plant metabolism data for quinclorac on commodities similar to cranberry
. 4. These data are not being required at this time. However, any further exp ansion of the use of quinclorac to other commodities grown on larger acreages than rhubarb and cranberry , will trigger a requirement of additional metabolism data. **860.1400 Water, Fish, and Irrigated Crops** 5. Data on catfish and crayfish are required, or the label must prohibit use of treated water from rice and cranberry fields for aquaculture. For registration review, the PM must ensure that all quinclorac labels with uses on rice and cranberry

contain such a restriction. **860.1480 Meat, Milk, Poultry, and Eggs**  6. Tolerances in livestock commodities are not pertinent to the current petition. However, tolerances in livestock commodities will be changed in connection with Registration Review. **860.1500 Crop Field Trials** 7. Field trial data are adequate to determine quinclorac, per s e. IR
- 4 should not e the current guidance for differentiating field trial sites. 8. Field trial data are adequate to support the existing uses of quinclorac on rice, grain sorghum, barley

(imported), and pasture and range grasses. 9. The establ ished tolerance on aspirated grain fractions should be revoked as it is not needed. The tolerance on rice straw may be revoked, as rice straw is no longer considered a significant livestock feedstuff. **860.1650 Submittal of Analytical Reference Standards**  10. Albaugh must supply the Pesticide Repository

with analy

tical standards for quinclorac and the quinclorac methyl ester. 11. An analy

tical standard for the quinclorac DMA salt must be submitted to the EPA National Pesticide Standards Reposi tory . **860.1550 Proposed Tolerances** 12. A tolerance for residues of quinclorac on rhubarb may be set at 0.5 ppm. A tolerance for residues of quinclorac on low growing berries, except strawberries, subgroup 13
- 07H,Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **4** of **32** may be set at 1.5 ppm. At the time of public ation of this tolerance, the tolerance for residues quinclorac on cranberry in § 180.463(b) should be revoked , since the tolerance being set will cover the Section 18 use
. 13. Inaddition, IR
- 4 should be reminded to use the OECD tolerance calculation procedure s. 14. Revisions to current tolerances for registration review are documented in Table 7. **Background** Quinclorac is a herbicide for the selective post
- emergent control o f various annual grasses and broadleaf weeds
. Quinclorac is adsorbed via the root system and partially through the foliage and acts as an inhibitor of cell wall sy nthesis
. The nomenclature of quinclorac and quinclorac DMA salt are summarized in Table 1, and the physicochemical properties of are summarized in Table 2.

**T able**  **1. Quincl**  **orac and Quinclorac (DMA salt) Nom enclature.**  Compound

N Cl Cl

O O H

Common name Quinclorac, Company experimental name BAS 514 34H IUPAC name 3,7
- dichloroquinoline
- 8
- carboxylic acid CAS name 3,7
- dichloro
- 8
- quinolinecarboxylic acid CAS re gistry number 84087
- 01
- 4 Molecular weight 242.1 End
- use product (EP) Drive® 75 DF Compound

**N Cl** 

**Cl**

**O O**  **N H**  **C H**  **3 C**  **H 3**  **H +** Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **5** of **32 T**  **able 1.**  **Quincl orac and Quinclorac (DMA salt) Nom**  **enclature.** Common name Quinclorac, DMA salt Company experimental name BAS 514 51H IUPAC name 3,7
- dichloroquinoline
- 8
- carboxylic acid, DMA s alt CAS name 3,7
- dichloro
- 8
- quinolinecarboxylic acid, DMA salt CAS registry number 84087
- 48
- 9 Molecular weight 287.2 End
- use product (EP) Drive®XLR8 Herbicide, EPA Reg. No. 7969
- 272; Paramount® L Herbicide, EPA Reg. No. 7969
- GRA; Facet L Herbicide, EPA Reg. No. 7969
- GRL Note: Phy sicochemical properties of the technical grade quinclorac are reported below. Only several p hy sicochemical properties of the DMA salt of quinclorac are available
. **T able**  **2. Physicochem** **ical Properties of the Technical Grade Quinclorac**  **.** Parameter Value Reference Melting point/range ~269°C D342446 , M. Doherty, 9/11/07 pH 3.4
- 3.5 RCB 3283 S. Hummel, 2/26/88 Density ~560 g/L D342446, M. Doherty, 9/11/07 Water solubility (20°C) 0.0064 g/100 mL Solvent solubility (g/100 mL at 20°C to 25°C) ethanol 0.2 toluene <0.1 Lutrol® <0.1 acetone 0.2 olive oil <0.1 n - octanol <0.1 acetonitrile <0.1 1,2
- propandiol <0.1 ethyl acetate 0.1 dichloromethane <0.1 ethyl ether 0.1 n - hexane <0.1 Vapor pressure (20°C) <1.0×10 - 7 mb ar (<0.75×10 - 7 Torr) Dissociation constant, pK a 4.34 at 20°C 4.35 at 25°C Octanol/water partition coefficient, log P OW (20°C) 1.76 at pH 4

- 0.74 at pH 7 3.74 at pH 10 UV/visible absorption spectrum 314 nm, 300 nm, 278 nm (95% ethanol) MRID 48051092Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **6** of **32 Table 2.**  **Phy sicochem** **ical Properties of the Quinclorac, DMA Salt.** Parameter Value Reference Melting point/range NA pH NA Density NA Water solubility (20°C) NA Solvent solubility (g/100 mL at 20°C to 25°C) NA Vapor pressure (20°C) NA Dissociation constant, pK a 4.3 3 ± 0.15 (Tem perature not reported) MRID 48051092 Octanol/water partition coefficient, log P OW (20°C) NA UV/visible absorption spectrum 314 nm, 300 nm, 278 nm (95% ethanol) MRID 48051092 Inaddition, the registrant has submitted a comparative study of the dissociation behavior of quinclorac and its dimethylamine salt (MRID 48051902, “Comparative study of the Dissociation Behavior of Quinclorac Acid and its Dimethylamine Salt” )
. The UV/Vis spectra of quinclorac TGAIand the UV/Vis spectra and dissociation constant of quinclorac DMA were presented
. The results of the study

show that in aqueous solutions, the chemical form of the quinclorac dimethyl amine salt is the same as that of the quinclorac acid form.

**860.1200 Directions for Use** Ther e are currently five quinclorac EPs registered to BASF in the U.S. for use on food/feed crops , three of which contain only quinclorac and two that are multiple active ingredient (MAI) formulations. The single active ingredient formulations include a 50 % W P and a 75% DF for use on rice (EPA Reg. No s . 7969
- 93 and 7969
- 313 ) and a 75% DF for use on wheat , sorghum, and grasses grown for seed (EPA Reg. No. 7969
- 113). The two MAIformulations are both 75% DF formulations; one contain s 15% quinclorac and 60% 2,4
- D and is registered for use on wheat and sorghum (EPA Reg. No. 7969
- 152), and the other contain s 62% quinclorac and 13% imazethapy

r and is registered for use on rice. Proposed new uses. IR
- 4 is proposing use of the Quinclorac 4
- L AG (Reg. No. 42750
- 169 ), registered to Albaugh, Inc., containing 3.8 lb quinclorac/gallon, in connection with the current petition.Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **7** of **32 Table 3.**  **Summary of Proposed**  **Directions for Use Quinclorac 4**  **- L AG** 
Formulation [EPA Reg. No.] , a.i. Applic. Timing, Type, and Equip. 1 Appli c. Rate (lb ai/A) Max.

Seasonal Applic. Rate (lb ai/A) PHI

(days) Use Directions and Limitations 2 Rhubarb Quinclorac 4
- L 42750
- 169 , 3.8 lb/gal DF, Quinclorac Foliar ground application

in 10 gal water, timing not specified. A second application at leas t 30 days after the first application 0.37 0.75 3 0 Crop oil concentrate permitted.

Low Growing Berries, except Strawberry, subgroup 13
- 07H Quinclorac 4
- L 42750
- 169 , 3.8 lb/gal DF, Quinclorac Foliar ground application

in 10 gal water, timing not specifie d. A second application at least 30 days after the first application 0
. 5 0 1.0 60 Adjuvants not mentioned
.
Conclusions. Cranberry

i s an aquatic crop, and as such, a label restriction is needed reg arding the use of tr eated rice and cranberry fields for a quaculture. Alternatively , the petitioner can determine residues in catfish and crayfish raised in treated fields and propose tolerances for these commodities , if necessary
. The label provided for Quinclorac/QuinStar 4
- L does not contain any restriction against aquaculture. Existing Uses. Existing uses of quinclorac include use on rice, grain sorghum, wheat, pasture and rangeland grasses, and use on barley in Canada for import into the US. The dimethylamine salt of quinclorac has recently been register ed for use on rice, grain sorghum, and wheat. The current uses are as described under 860.1500 Field Trials. **8 60.1300 Nature of the Residue**  **- Plants**  D241204, J. Stokes, 11/6/1998 The qualitative nature of quinclorac residues in plants was considered ade quately understood for the currently

registered uses, based upon the metabolism studies on rice, grain sorghum, and wheat. In each of these studies, the major 14 C
- residue in/on various matrices was identified as parent compound. Based on the metabolite p rofiles observed in these studies, quinclorac undergoes hydroxylation of the quinoline ring of the parent, followed by conjugation with glucose and other biologically available compounds at the hydroxlated site. S ome radioactive residues are incorporated into the high molecular weight natural products. Based on the above studies, HED concluded that parent is the only residue of concern in plant commodities for purposes of the tolerance expression and risk assessment. However, all three metabolism studie s are on grain commodities. A 4 th metabolism study , on canola, is available but has not been reviewed. **Metabolism in Rice**
. (MRID 41063534 ). The metabolism of 14C
- ring labeled quinclorac in rice plants was studied under growth chamber and field conditio ns. Growth chamber plants were treated at 1.4 lb.ai/A 14C
- BAS 514H, an exaggerated dosage rate, at the four leaf stage of plant development. Growth
- chamber rice plant samples were harvested for analysis at PHI=97 day s.Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **8** of **32** Field plants were tr eated at 0.75 lb /A 14C
- BAS 514H, at the 3
- 5 leaf stage. The treatment level of field plants simulates the expected herbicide use rate. Field rice plants were harvested at P HI= 28 and 118 day s. Greater than 84% of the TRR in rice grain or straw was identified as the parent compound, quinclorac. **Metabolism in Sorghum** : (MRID #44322211). Preemergence and post emergence applications of radiolabeled quinclorac were made to a confined sorghum plot. The soil was a loamy sand soil with low organic matter. Treatment levels we re 0.47 lb ai/A preemergence (0 DAT) and 0.45 lb a.i./A postemergence (25 DAT) for a total of 0.92 lb ai/A. Crop samples were collected and analy zed at various stages of maturity , including forage samples collected at twenty
- five day s after the postemerge nce treatment, and mature stover and grain collected at the final harvest (120 DAT). **TABLE 4**  **. Distribution and Identification of Residues from Sorghum RACs Treated at 0.92 lb a.i./A.** 

RAC Radioactive Residues

Identified Unidentified Residuum quinclorac quinclorac methyl ester Soluble polars Organosoluble ppm %TRR ppm %TRR ppm %TRR ppm %TTR ppm %TRR ppm forage 4.01 73.4 2.94 3.6 0.145 18.7 0.750 4.7 0.188 <1 <0.01 fodder 0.87 21.5 0.186 5.9 0.051 52.4 0.455 19.4 0.169 <1 <0.01 grain 0.83 73.5 0.610 1.7 0.014 5.5 0.044 6.6 0.055 <1 <0.01 The radioactive residues of quinclorac found in sorghum following ty pical agricultural practices consist predominantly

of parent compound. A minor metabolite, the methy l ester of quinclorac, is found i n all tissues, but alway s at less than 10% TRR. A lower percentage of the residue in sorghum fodder was found to be quinclorac, but the majority of the residue was soluble polar compounds. The current analy tical methodology

(BASF Method No. A8902) emplo ys a similar acetone extraction step as used in the above extractions. Therefore, the accountability of the residues is high. **Metabolism in Wheat** : (MRID #44322207). The test substance used in this study was quinclorac (labeled at the 3 position) at two application rates (0.112 lb ai/A (0.45X the proposed rate) and 0.446 lb ai/A (1.8X the proposed rate)). Only the higher application rate is presented in the table below. Plants were grown in greenhouse conditions and sprayed 22 day s after plantin g, when they

were in the 3 to 5 leaf stage. Forage samples were collected at a 37
- day PHI , straw and grain at a PHI

of 92 day s. **TABLE 5**  **. Distribution and Identification of Residues from Wheat RACs Treated at 0.446 lb ai/A Quinclorac.** 

RAC Radioac tive Residues Identified Unidentified Unextracted Marc quinclorac quinclorac methyl ester aqueous acetone soluble hydrolyzable non - hydrolyzable %TRR ppm %TRR ppm %TRR ppm %TRR ppm %TRR ppmQuinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **9** of **32** ppm forage 13.1 45.1 5.9 6.4 0.84 38.4 5.1 10.3 0.34 1 .9 0.06 straw 8.2 22.4 1.8 12.6 1.0 45.1 3.7 12.4 0.23 3.3 0.06 grain 3.9 68 2.7 3.7 0.15 17.2 0.68 3.3 0.04 0.3 <0.01 The primary

path by which plants metabolize quinclorac is through the hydroxylation of the quinoline ring of the parent, followed by the conjugation of glucose and other biologically available compounds at the hydroxlated site. Ultimately , some radioactive residues are incorporated into the high molecular weight natural products. The petitioner, IR
- 4, requests a waiver from the requi rement of another metabolism study based on the following. Inthe studies to date it has been shown that in plants the primary path by which quinclorac is metabolized is through hydroxylation of the quinolone ring of the parent, followed by

the conjugatio n of glucose and other biologically available compounds at the hydroxylated site. These results were similar for all quinclorac metabolism studies submitted to date
. Rhubarb and cranberry

are very low acreage crops. Cranberry is commercially

grown on just over 40,000 acres , and Rhubarb is commercially grown on approximately 2,000 acres in the US (based on 2002 census of Agriculture). Inaddition, o ther related quinoline compounds, such as quinoxyfen have shown similar metabolism results in that the parent is the primary residue component (D276835 , 3/26/2003, G. Kramer) when conducted on a wide variety of plant matrices (cucumber, grape, sugarbeet, and tomato). In these studies, quinoxyfen was the primary residue component and other remaining compounds were incorporated into natural plant constituents. Incucumber and tomato, unchanged quinoxyfen remained largely on the surface of treated plants. The presence of multiple unidentified polar residues suggests that metabolism of quinoxyfen does occur to some extent to form more polar soluble components with the incorporation into insoluble material.

TABLE 1. Test Compound Nomenclature for the similar pesticide Quinoxyfen Common name Quinoxyfen Company name DE
- 795 Chemical Class Quinoline fungicid e IUPAC name 5,7
- dichloro
- 4
- quinolyl 4
- fluorophenyl ether CAS name 5,7
- dichloro
- 4
- (4
- fluorophenoxy)quinoline CAS # 124495
- 18
- 7 End
- use product/EP Quintec ® Chemical Structure N

O F C l

C lQuinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **10** of **32** Conclusions. While the metabolism of quinclorac is adequately understood with regard to the currently registered uses, there are no plant metabolism data for quinclorac on commodities similar to cranberry . These data are not being required at this time. However, any further expansion of the use of quincl orac to other commodities grown on larger acreages than rhubarb and cranberry , will trigger a requirement of additional metabolism data. The methyl ester of quinclorac was reported in some grain commodities at <15% of the TRR. The methyl ester is measure d by the enforcement method , which includes a methylation step. **860.1300 Nature of the Residue -**  **Livestock** D241204, J. Stokes, 11/6/1998 D325790, M. Doherty, 9/13/2007 The qualitative nature of quinclorac residues in livestock is u nderstood based upon the adequate goat and poultry

metabolism studies (MRIDs 41076104 and 41063535 , respectively ) . In both studies, quinclorac was the principal residue identified in each commodity
. HED concluded that parent is the only

residue of concer

n for risk assessment and tolerance expression for livestock
. However, the enforcement method includes a methylation step and determines the methyl ester of quinclorac. Ina rat metabolism study (MRID 41063533 ), quinclorac was the primary metabolite rep orted. Elimination was primarily in the urine (91
- 98%) with small amounts in the feces (1
- 4%) eliminated by

day 5 after dosing. Conclusions. No further livestock metabolism data are required at the present time
. **860.1340 Residue Analytical Methods** D241 204, J. Stokes, 11/6/1998 DEB 5554, J. Garbus, PP#9F3755/9H5583, 8/7/90 Adequate analy

tical methods (GC/ECD) are available to enforcing quinclorac tolerances on plant (BASF Method A8902; MRID# 41063537) and livestock (BASF Method 268/1; MRID# 41063536) co mmodities. Both methods have undergone successful agency method validation trials and have been submitted to FDA for publication in PAM II as the tolerance enforcement methods. The L OQ of both methods is 0.05 ppm for all matrices. InBASF Method 268/1 , used for both plant and anim a l matrices, samples are soaked in 0.1 N NaOH for 1 hour and then extracted with acetone, pH adjusted with sodium bicarbonate, and then the extract is extracted several times with dichloromethane. Organic extracts are combine d, redissolved in ether and methanol, treated with diazomethane, and taken to dry ness. (No suitable substitute was found for the diazomethane.) The methylated residue is dissolved in 75% dichloromethane/hexane and cleaned up with silica gel . The eluant f raction containing the methylated q

u inclorac is evaporated to dry ness and redissolved in acetone/hexane. An aliquot is subjected to GC chromatography using a DB
- 5 column and electron capture detection. Methylate d standard is used for quantitation. The L O D was reportedly 0.05 ppm, but this wasQuinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **11** of **32** also the lowest level validated. Inthe current field trials, residues of quinclorac in/on rice, wheat, and sorghum plant parts were determined using a LC/MS /MS method (BASF Method A9708 /1 ). This method was adequat ely validated in conjunction with the analysis of field trial samples. Crop samples were soaked in 0.1 N NaOH for 1 hour and then extracted with acetone. The extract was concentrated to remove the acetone, and then acidified. Residues were next partitio ned into dichloromethane, concentrated to dry ness , redissolved in 0.0025 N NaOH, and adjusted to pH 8
- 11. Residues were then cleaned up using a quaternary amine SPE column, and analy zed by L C/MS/MS using exter

nal standards. The 240 →196 m/z ion transition was used to detect and quantify

residues. The validate d LOQ for quinclorac is 0.05 ppm in both matrices , and the L OD was not reported. With only one ion transition monitored, the L C/MS/MS method cannot be co nsidered suitable for enforcement, but it is suitable for data collection. Conclusions. An adequate GC/EC D method is available for enforcing the propo s ed tolerances, and the field trial data were collected using an LC/MS /MS method adequate for determinin g quinclorac, per se. I f LC/MS/MS is tobe used, a method is needed for the methyl ester of quinclorac and any

other metabolites found in the required metabolism study
. **860.1360 Multiresidue Methods** PP # 9F3755 , J. Garbus, 08/07 /90 Adequate data are avail able evaluating quinclorac through the FDA Multi
- Residue Methods Test guidelines, and quinclorac is detected by Protocol B. Quinclorac is not detected by the other FDA MRM protocols. **860.1380 Storage Stability** D241204, J. Stokes, 11/6/1998 PP # 9F3755 , J. Garbus, 08/0 7 /90 Adequate data are available indicating that quinclorac (and the methyl ester) is stable under frozen storage conditions for up to 37
- 40 months in rice grain and straw, corn grain, forage, silage, and fodder, soy

bean grain and fodder, sug ar beet roots and tops, alfalfa hay , sorghum forage, hay , silage, and fodder. Storage stability

of quinclorac residues in livestock tissues was assessed by reanaly zing tissue samples after a period of time equal to their storage prior to the in i tial ana ly sis. Stability in animal and plant tissues has been demonstrated in accountability studies where plant and animal tissues were stored for 3 years between radiochemcial and chromatography analy ses (See J. Garbus, 08/02/90). Inaddition, IR
- 4 provided co ncurrent storage stability data for rhubarb and cranberry , demonstrating stability

for the time and conditions the samples were stored. Conclusions. The available storage stability data are adequate and support the storage conditions and d urations incurr ed in the existing field trials , for currently registered uses
. The IR
- 4Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **12** of **32** concurrent storage stability data for rhubarb and cranberry are adequate for residues of quinclorac , demonstrating stability for the time and conditions the samples were stored. Sto rage stabil i ty data are needed for residues of the methyl ester of quinclorac and other residues of concern found in any

future metabolism study
. **860.1400 Water, Fish, and Irrigated Crops** For existing use on rice and the proposed use on cranberry , a labe l restriction is needed reg arding the use of tr eated rice and cranberry fields for aquaculture. Alternatively , the petitioner can determine residues in catfish and crayfish raised in treated fields and propose tolerances for these commodities if necessary
. The label provided for Quinclorac/ QuinStar 4
- L does not contain any restriction against aquaculture. Conclusions. Data on catfish and crayfish are required, or the label must prohibit use of treated water from rice and cranberry fields for aquaculture
. For registration review, the PM must ensure that all quinclorac labels with uses on rice and cranberry contain such a restriction. **860.1460 Food Handling** This guideline topic is not relevant to the proposed use. **860.1480 Meat, Milk, Poultry, and Eggs** DP# D241204, J. Stokes, 11/6/1998 DP# D358151, G. Oatkie, 04/30/2009 Adequate cattle and poultry feeding studies are available
. The uses proposed in this petition do not involve livestock feeds, and w ill not affect the existing tolerances on meat, milk, poultry and eggs . For registration review, we are recommending that the tolerance on Grain, aspirated fractions be revoked, since data have been received demonstrating that the tolerance is not needed, as residues on aspirated grain fractions (AGF) are no higher than the tolerances on the grains. AGF were the highest contributor to the livestock dietary burden, but tolerances have since been established for grass commodities , which is now the highest contributor to the livestock dietary burden
. Dietary burdens for livestock were recalculated in connection with the petition for residues of quinclorac on pasture and rangeland grasses. ( D358151 , 04/30/2009, G. Otakie, MRID 45066302). In the review of that petition we concluded: As the use on grasses does not substantially alter the calculated MDB for cattle (275 vs 290 ppm), no changes are necessary in the existing tolerances for milk and meat, fat and meat by products of cattle, goats, horses and sheep. However, the recalculated MDBs for poultry and swine indicate that the existing tolerances for poultry and hog commodities should be reassessed. These data support the current 0.05 ppm tolerances (L OQ) for eggs and poultry fat and meat, and indicate that the current 0.1 ppm tolerance for poultry meat by pro ducts should be lowered to 0.05Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **13** of **32** ppm. HED notes that lowering the tolerance for poultry meat by products to 0.05 ppm will also harmonize this tolerance with the existing Canadian MRL for poultry

meat by products. These data support the current 0.05 ppm tole rance (LOQ) for hog meat, and indicate that the current tolerances for hog fat (0.7 ppm) and hog meat by products (1.5 ppm) should also be lowered to 0.05 ppm. L owering the tolerances for these commodities will also harmonize the U.S. tolerances with the e xisting Canadian MRL s for hog fat and meat by products. Conclusions. Tolerances in livestock commodities will be changed in connection with Registration Review. **860.1500 Crop Field Trials** 48697501.der.doc Rhubarb 48697502.der.doc Cranberry Cranberry (fo r Low Growing Berries exc ept strawberry, subgroup 13

- 07. Five cranberry field trials were conducted in the United States during the 2009 growing season, in North American Free Trade Agreement (NAFTA) Growing Zones 1 (MA; 2 trials), 5 (WI ; 2 trial), and 12 (OR; 1 trial). The two MA trials (MA01 and MA03) and the two WI trials (WI 01 and WI 02) were each conducted using the same Field Research Director (FRD). Careful examination of the field trial records indicates that the only difference between each pair of trials was the use of different varieties of cranberry , and distance between MA trials of > 20 miles, and different soil characterics for the MA trials. HED has concluded that there are insufficient distinguishing characteristics to classify

the WIpa ir as separate trials; however, the trials were conducted prior to development of the guidance on field trial differentiation. Following two foliar broadcast applications of the 3.8 lb ai/gal SC formulation of quinclorac at 0.484
- 0.528 lb ai/A, residues o f quinclorac (and per trial averages) in/on cranberry harvested at a 57
- to 62
- day

PHIwere 0.15
- 0.68 (0.16
- 0.67) ppm. Applications were made at a 28
- to 32
- day retreatment interval (RTI) using ground equipment in spray volumes of 29.7
- 35.3 gal/A. A crop oil concentrate (COC) was added to the spray mixture for each of the applications at 2 pints/A. Rhubarb. Four field trials were conducted in the United States during the 2009 growing season in the North American Free Trade Agreement (NAFTA) Growing Zo nes 5 (MI ; 1 trial) and 12 (OR; 3 trials). The two rhubarb trials in Canby , OR (OR11 and OR12) and the trial in Hillsboro, OR (OR10) were conducted by the same Field Research Director (FRD). Careful examination of the field trial records indicates there are sufficient distinguishing characteristics to classify the Hillsboro, OR trial as a separate trial from the Canby , OR trials, based on location (>20 miles apart) and spray

volume (>25% higher at the Hillsboro site). There are insufficient distinguishin g characteristics to classify the two Canby , OR trials as separate trials; therefore, the Canby , OR trials constitute a single trial with replicate samples for purposes of 860.1500 data requirements. The adjustment in trial numbers results in a total of three field trials, with one trial in Zone 5 and two trials in Zone 12. Following two foliar broadcast applications of the 3.8 lb ai/gal SC formulation of quinclorac at 0.736
- 0.798 lb ai/A, residues (and per trial averages) of quinclorac in/on rhubarb harv ested at a 29
- to 33
- day

PHIwere 0.05
- 0.231 (0.082
- 0.205) ppm. The method L OQ was 0.05 ppm.Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **14** of **32** Applications were made at a 28
- to 31
- day retreatment interval (RTI) using ground equipment in spray volumes of 19.9
- 36.7 gal/A. A crop oil concentrate (COC) wa s added to the spray mixture for each of the applications at a rate of 1
- 2 pints/A. Conclusions. Field trial data are adequate to determine residues of quinclorac, per se. IR
- 4 should not e the current guidance for differentiating field trial sites. **Existing Uses of Remaining Crops** Existing uses of Quiclorac include use on rice, wheat, soy beans, barley

(import), grass forage and hay . Each is discussed below , followed by a summary

of available data for the dimethylamine salt of quinclorac (quinclor ac DMA). Rice . (D 241198 , 10/01/98, J. Stokes, MRID 44323101) Field trial data were submitted from fifteen sites in five states [(MS (3), AR (4), LA (5), MO (1), and TX (2)]. Data from CA were not included since the DF formulation is not registered in C A. Rice was treated at 0.5 lb a.i./A with the DF formulation, with a 40
- day PHI(time before flooding the field). Residue decline samples from a plots in MS and AR at
- 6,
- 3, +3, and +6 before and after the targeted growth stage harvest per RAC. The re sidues of quinclorac on rice grain ranged from 0.346 ppm to 4.35 ppm, and averaged 0.987 ppm. The residues of quinclorac on rice straw ranged from 0.120 ppm to 2.74 ppm, and averaged 1.07 ppm. The established 5.0 ppm and 12.0 ppm tolerances are adequate t o cover residues of quinclorac in harvested rice grain and straw, respectively , with a 40
- day PHI
. Grain sorghum and wheat D241204; D248880; D248881, 11/06/98; PP#9F3755, J. Stokes Grain Sorghum (MRID#’s 44322212, 44583102). **MRID#44322212** : Four grain sorghum field trials with quinclorac 75% DF were conducted in KS, NE, OK, and TX. A single postemergence broadcast spray application was made with FACET 75 DF Herbicide (EPA Reg. No. 7969
- 113, 75% a.i. quinclorac) at a rate of 0.25 lb a.i./A at the six l eaf stage. Samples were collected at two stages of crop maturity , i.e., at the late dough stage for forage (54 to 83 DAT), and at grain/stover harvest (81 to 108 DAT). Residues of quinclorac ranged from <0.05 ppm to 0.15 ppm in sorghum forage, <0.05 ppm to 0.26 ppm in sorghum grain, and all samples were <0.05 ppm in sorghum stover. At the KS plot additional samples were collected for a residue decline study ; samples were collected at
- 10,
- 5, +5, and +10 day s in addition to the target stage samples. All of the samples of sorghum grain and forage/stover had residues <0.05 ppm. **MRID#44583102** : Twelve field trials trials with quinclorac 75% DF were conducted in nine states. Grain sorghum was treated with one preemergence and one post emergence application of FACET DF at the rate of 0.5 lb a.i./A per application. (0.84X maximum seasonal application rate (preergemence + postemergence: 0.25 lb a.i./A + 0.38 lb a.i./A = 0.63 lb a.i./A)). The maximum seasonal rate is 0.75 lb a.i./A. The preemergence applic ation was timed prior to planting and the postemergence allocation was 60 to 65 days before harvest of grain and stover. Plants were harvested for forage and hay immediately

after flowering or 30 day s after the lastQuinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **15** of **32** treatment. Silage was targeted to be h arvested at the soft dough stage of the plant growth. Maximum residues were reported as 3.67, 6.68, 4.50, 3.13, and 1.08 ppm in grain sorghum forage, grain, hay , silage, and stover, respectively . Tolerances for residues on quinclorac were set at 6.0 ppm for sorghum grain, 3.0 for sorghum forage, and 1.0 for sorghum fodder. Wh eat **MRID#44322208** : Twelve winter wheat field trials were conducted in 12 states. A single broadcast preplant application of FACET 75DF was made at a rate of 0.25 lb a.i./A. T hre e additional plots in KS, OK, and TX received a single broadcast application at twice the label maximum rate, i.e., 0.5 lb a.i./A.. Samples were harvested according to normal crop maturity a s follows: forage, 46 to 224 DAT, dried hay , 162 to 268 DAT, an d grain and straw, 194 to 324 DAT. Maximum residues in wheat commodities from the 0.25 lb ai/A rate were reported as 0.88, 0.32, 0.24, and 0.08 ppm quinclorac in forage, hay , grain, and straw, respectively ; and 1.55, 0.54, 0.56, and 0.12 ppm quinclorac i n forage, hay , grain, and straw, respectively , from the 0.50 lb ai/A rate. Tolerances for residues of quinclorac were set on wheat forage (1.0 ppm), hay ( 0.5 ppm), grain (0.5 ppm), and straw (0.1 ppm). Barley (imported). Data for residues of quinclorac DF formulation were reviewed by PMRA. Twelve field trials with s pring barley , gro wn in the prairie provinces, were conducted. The barley was treated with one ground application of Facet 75 DF at a target rate of 0.200 kg a
. i
. /ha [0.18 lbs a.i./A] (2x rat e or Canadian GAP). A surfactant was added to the tank mix. Forage samples were harvested 16
- 30 day s following application, while grain and straw were harvested 63
- 97 day s following application. Residues in forage ranged from <0.05
- 2.01 ppm. The highest average field trial residue (HAFT) found in forage was 1.78 ppm. In the grain, individual residues ranged from <0.05
- 1.25 ppm. The HAFT in the grain was 1.165 ppm. In the straw, the residues ranged from <0.05
- 0.484 ppm, with the HAFT being 0.299 ppm. A tolerance of 2 ppm was established for residues of quinclorac on barley grain. Aspirated Grain Fractions(AGF): Data for quinclorac aspirated grain fractions were not submitted for the original grain petitions. The needed tolerance for AGF was estimated at 200X the 6.0 ppm tolerance for sorghum grain (200 X 6.0 = 1200 ppm). Data were later provided. (D344496, 09/25/08; GOtakie: Quinclorac. Magnitude of the Residue in Wheat and Sorghum Aspirated Grain Fractions. MRIDs 45598703 and 45598704.) Two fiel d trials were conducted for quinclorac (BAS 514 H) on wheat aspirated grain fractions and sorghum aspirated grain fractions. The studies were conducted in the United States in Zone 5 (York County , Nebraska) during the 1999 growing season. Residues of qui nclorac were quantitated at 0.453 and 0.516 ppm in/on wheat AGFs following two applications of BAS 514 H at 0.25 lb ai/A/application (0.50 lb ai/A/season). Residues of quinclorac were quantitated at 0.147 and 0.145 ppm in/on sorghum AGFs following two app lications of BAS 514 H at 0.25 and 0.50 lb ai/A/application (0.75 lb ai/A/season). Ash content was between 12.0 and 17.5% in all wheat AGF samples and between 5.5 and 9.0% in all sorghum AGF samples. Tolerances for quinclorac established under 40 CFR 180.4 63 are 0.5 ppm and 6.0 ppm on wheat and sorghum grain, respectively . Average residues at the maximum application rate in aspirated grain fractions were 0.48 and 0.15 ppm, in wheat and sorghum respectively . Accordingly , separate tolerances on aspirated gra in fractions are not required, pending submission of detailed weather data, throughout the residue trial period. The existing tolerance for residues ofQuinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **16** of **32** quinclorac on AGF should be revoked. Pasture and Rangeland Grasses

. ( D358151 , 04/2 3/2009, G. Otakie, MRID 45066302). Thirteen field trials conducted in the United States in Zones 2, 4, 5, 6, 7, 8, 9, 10, and 11 during 1999 , quinclorac (75% DF) was applied to representative grass species as a single broadcast foliar application during vegetative developme nt at rates of 0.746
- 0.780 lb ai/A (1x rate). All applications were made using ground equipment in volumes of 9
- 41 gal/A, and include both MSO ( 0.5
- 3.3% v/v) and aqueous UAN ( 0.7
- 5.6% v/v) as adjuvants. Following a single foliar application of quinclorac (DF) to grasses at ~1x the proposed rate , residues were 36.3
- 105.9 ppm in/on 26 samples of forage harvested at 0 DAT and 3.6
- 70.1 ppm in/on 26 samples of hay

harvested at 7
- 8 DAT. Average quinclorac residues were 68.3 ppm for forage and 24.3 ppm for hay , and the HAFT residues were 105.7 ppm for forage and 58.5 ppm for hay . The residue decline data indicate that residues in/on forage declined steadily from an average of 43.1 ppm at 0 DAT to 7.1 ppm by 15 DAT. For hay , residues initially increased from 70 ppm at 0 DAT to 83.5 ppm at 3 DAT , but then declined steadily to 24.3 ppm by 15 DAT. Tolerances for residues of quinclorac were set at 150 ppm for grass forage and 130 ppm for grass hay based on these data. Comparison of Quinclorac with Quinclorac DMA i n rice, wheat, and sorghum. S ix field trials, each consisting of side
- by
- side trials comparing the dry flowable (DF) and the soluble liquid (SL) formulations of the dimethylamine salt (DMA) of active ingredient, were conducted in geographically

diverse lo cations. The results from these trials indicate d that there wa s no discernable difference between the residues SLDMA salt in rice, wheat, and grain sorghum obtained using the dry flowable (DF) or soluble liquid (SLDMA) formulations of quinclorac. Conclusions. Field trial data are adequate to support the existing uses of quinclorac on rice, grain sorghum, barley

(imported), and pasture and range grasses. Indecline studies on grains, when detectable residues were initially reported, residues generally degraded substantially within 14 day s. The established tolerance on aspirated grain fractions should be revoked as it is not needed. The tolerance on rice straw may be revoked, as rice straw is no longer considered a livestock feedstuff.
**860.1520 Proce ssed Food and Feed**  There are no processed commodities in connection with the current petition. For registration review, p rocessing studies submitted to support existing tolerances are adequate. Process ing studies were submitted for Rice (MRID 41063543 ) , Sorghum ( MRID 44322213), and Wheat ( MRID 44322209 ).Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **17** of **32 Table 6.**  **Average Processing Factors for Sorghum Commodity**  **Processing Factor (x)**  Rice, hulls 1.1 Rice, bran 3.5 Rice, milled 0.76 Grain sorghum flour (dry milling) 0.90 Grain sorghum starch ( wet milling) 0.04 Wheat, bran 1.8 Wheat, middlings 0.79 Wheat, shorts 1.24 Wheat, flour 0.66 Wheat, germ 2.8 Tolerances for residue of qui n clorac of 1.0 ppm, 1.5 ppm, and 0.75 ppm, were set for wheat bran, wheat germ, and wheat shorts, respectively
. Conclusions. Available processing data are adequate to support the currently registered uses of quinclorac. Residues concentrate on hulls and some milling fractions. **860.1650 Submittal of Analytical Reference Standards** Analy tica l standards for quinclorac and the quinclorac methyl ester are available from BASF, but not from Albaugh , Inc. The methyl ester of quinclorac is used as an analy tical standard for the quinclorac enforcement method. Albaugh must supply the Pesticide Reposi tory

with analy

tical standards for quinclorac and the quinclorac methyl ester. An ana ly tical standard for the quinclorac DMA salt must be submitted to the EPA National Pesticide Standards Repository
. **860.1850/1900 Confined and Field Accumulation in Rotat ional Crops**  DP# D241204, J.Stokes, 11/6/1998 A dequate rotational crop stud ies are available to support the use of quinclorac. (MRID 42294108, 42294109

– confined rotational crop; MRID 41781428

– field rotational crop) The confined rotational crop studi es are summarized in the tables below. No quantifiable residues (<0.05 ppm for the current enforcement method) were reported in chard, or beet tops or roots 10 months (309 days) after treatment at the 1x application rate of 0.5 lb ai/A. Detectable residu es were reported in chard 1 months after a 2x application rate of 1.0 lb ai/A.Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **18** of **32** Field rotational crop ( MRID 41781428 ). Rotational crop studies were conducted in LA and MS following the application o f 0.5 1b ai/A of quinclorac to rice that was harvested in the fall of 1987. N o residues greater than the limit of detection of 0.05 ppm quinclorac were found in mustard leaves and turnip leaves and roots when planted 4 months or 9 months ( 20 and/or 270 day s ) after a quinclorac application to rice . (The analy t ical method was validated down to 0.05 ppm, so 0.05 ppm may

be called the limit of quantitation (L OQ) or the lower limit of method validation (LLM V).Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **19** of **32**Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **20** of **32 860.1550 Proposed Tolerances**  The current tolerance expression for quinclorac is :

“ Tolerances ar e established for residues of the herbicide quinclorac, including its metabolites and degradates, in or on the commodities in the table in this paragraph. Compliance with the tolerance levels specified in this paragraph is to be determined by measuring onl y quinclorac, 3,7
- dichloro
- 8
- quinolinecarboxylic acid, in or on the commodity
. ” The tolerance expression is in accord with our current guidance on tolerance expressions. Permanent tolerances have been established for residues of quinclorac in/on small cereal grain commodities at levels ranging from 0.1 ppm in wheat straw to 15 ppm in rice bran [40 CFR §180.463(a)] , and for grass forage at 150 ppm and grass hay at 130 ppm . There is also a 1200 ppm tolerance for AGF; however, recently reviewed data indicat e that a tolerance on AGF is not necessary (DP# 344496, G. Otakie, 9/25/08). Permanent tolerances have also been established for residues of quinclorac per se in/on livestock commodities at levels ranging from 0.05 to 1.5 ppm. The tolerances being propos ed by IR
- 4 for the current petition are listed in Table 7, along the HED’s recommended tolerances. An adequate number of field trials at ~1x the proposed use rate are available for rhubarb and cranberry to support permanent tolerances. The Agency ’s SOP “ Guidelines for Setting Pesticide Tolerances Based on Field Trial Data” were utilized for determining the appropriate tolerance level for each commodity (Appendix I I). The recommended tolerance for rhubarb is 0.5 ppm, and the recommended tolerance for Lo w growing berries, except strawberries, subgroup 13
- 07H is 1.5 ppm
. Based on the recalculated dietary burden s for livestock and the data from the available cattle and poultry feeding studies, the current tolerances for livestock commodities are adequate, wi th the exception s of the tolerances on poultry meat by products and hog fat and meat by products . Based on the recalculated MDBs for swine (6.0 ppm) and poultry (5.4 ppm) and the data from the poultry and cattle feeding studies, the existing tolerances for poultry meat by products and hog fat and meat by

products are to o high as quinclorac residues in these commodities are expected to b e <0.05 ppm at 1x the MDB. Therefore, the tolerances for these livestock commodities should be lowered to 0.05 ppm. L owering the tolerances on these commodities will also harmonize the U.S. tolerances with the existing Canadian MRL s for poultry meat by products and hog fat and meat by products. Inaddition, HED notes that the Agency no longer considers rice straw to be a signifi cant livestock feedstuff (OPPTS 860.1000, Table I , ChemSAC memo 6/30/08). Therefore, the current tolerance for residues of quinclorac on rice straw may be revoked. CODE X has not established any established maximum residue limits (MRL s) for quinclorac. Canada has established maximum residue limits (MRL s) for quinclorac on selected agricultural commodities. An International Residue L imit Status Sheet is attached in Appendix I
.Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **21** of **32** The use of the DMA salt of quinclorac will not affect the established toleran ces for quinclorac on rice, grain sorghum, and wheat
. **Table 7. Tolerance Sum**  **ma ry for Quinclorac.**  **§ 180.463**  Commodity Current/Proposed Tolerance (ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition Low growing berries, except straw

b erries, subgroup 13
- 07H 1. 1 1.5 Revised level based on OECD tolerance calculation procedures. At the time of publication of this tolerance, the tolerance for residues quinclorac on cranberry in § 180.463 (b) should be revoked. Rhubarb 0.4 0.5 Revised leve l based on OECD tolerance calculation procedures. **Currently Established Tolerances Reevaluated for Registration Review**  Barley, grain 2.0 2.0 The tolerance needs a footnote to indicate that there are no U. S. Registrations. Cattle, fat 0.7 0.7 Cattle, meat byproducts 1.5 1.5 Cattle, meat 0.05 0.05 Egg 0.05 0.05 Goat, fat 0.7 0.7 Goat, meat byproducts 1.5 1.5 Goat, meat 0.05 0.05 Grain, aspirated fractions 1200 revoke Data submitted demonstrate that the tolerance is not needed. Current tole rance was based on a theoretical calculation. Grass, forage 150 150 Grass, hay 130 130 Hog, fat 0.7 0.05 Based on the residue data from the cattle feeding and the calculated MDB of 6.0 ppm for swine, the tolerances can be lowered to the method LOQ (0. 05 ppm). This level is harmonized with Canada. Hog, meat byproducts 1.5 0.05 Based on the residue data from the cattle feeding and the calculated MDB of 6.0 ppm for swine, the tolerances can be lowered to the method LOQ (0.05 ppm). This level is harmon ized with Canada.Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **22** of **32 Table 7.**  **Tolerance Sum ma**  **ry for Quinclorac. §**  **180.463** Commodity Current/Proposed Tolerance (ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition Hog, meat 0.05 0.05 Horse, fat 0.7 0.7 Horse, meat byproducts 1.5 1.5 Horse, meat 0.05 0.05 Milk 0.05 0.05 Poultry, fat 0.05 0.05 Poultry, meat byproducts 0.1 0.05 Based on the residue data from the poultry feeding and the c alculated MDB of 5.4 ppm for poultry, the tolerance can be lowered to the method LOQ (0.05 ppm). This level is harmonized with Canada. Poultry, meat 0.05 0.05 Rice, bran 15.0 15.0 Rice, grain 5.0 5.0 Rice, straw 12.0 Revoke Rice straw is no longer a regulated livestock feedstuff. Sheep, fat 0.7 0.7 Sheep, meat byproducts 1.5 1.5 Sheep, meat 0.05 0.05 Sorghum, grain, forage 3.0 3.0 Sorghum, grain, grain 6.0 6.0 Sorghum, grain, stover 1.0 1.0 Wheat, forage 1.0 1.0 Wheat, germ 0.75 0.75 Wheat, grain 0.5 0.5 Wheat, hay 0.5 0.5 Wheat, straw 0.1 0.1Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **23** of **32 References**  DP Barcode: None. CB 6228, 6229, 6230 Subject: P P#9G3797, FAP#0H5594, EUP# 7969
- EUP
- 25. Quinclorac (New Chemical on Rice with Tem porary To lerances). From: A. Aikins To: R. Taylo r /V. Walters Dated: 7/2 6/199 0 MRID(s): 410635 01 through
- 03, 41063534 through
- 46, 410761 01 and 41076104 DP Barcode: None. CB 5554 Subject: New

Chemical Review: PP#9F3755/9H5583: Quinclorac (FACET) in or on Rice Grain and Straw
. Evaluation of Analytical Method and Residue Data. From: J. Garbus To: R. Taylor/J. Miller Dated: 8/7 /199 0 MRID(s): 410635 01 through
- 03, 41063534 through
- 46, 410761 01 and 41076104
DP Barcode: None. EFED DER Subject: DER for Paulick, R.C. January 1991. Magnitude of the residues of quinclorac (BAS 514H) in

rotational crops (mustard and turnips) following rice culture in Louisiana (RCN 87096) and Mississippi (RCN 87098). BASF Report No. A9104. BASF Reg istration Document No. 91/5022. From: RJ. Mahler To: R. Taylor /V. Walters Dated: 11/5/1991 MRID(s): 41781428
DP Barcode: None. EFED DER Subject: DER for Nelson, DM. 1992. Accumulation study of 14C
- BAS 514H in fall planted confined

rotational crops. BASF Protocol No. M8909. BASF Report No. M9125. BASF Registratio n Document No. 92/5044. Unpublished study performed and submitted by BASF Corp. Agricultural Products, Research Triangle Park, NC. 107 pp From: RJ. Mahler To: R . Taylor /V. Walters Dated: 9/15 /199 2 MRID(s): 42294109 DP Barcode: None. EFED DER Subject: DER for Uinkler, V and JM Nelson. 1991. Accumulation of 14C
- BAS 514H in annual confined

rotational crops. BASF Protocol No. M8910. BASF Report No. M9123. BASF Registration Document No. 91/5170. Unpublished study performed and submitted by BASF Corp. Agric ultural Products, Research Triangle Park, NC. 104 pp. From: RJ. Mahler To: R . Taylor /V. Walters Dated: 9/17 /199 2 MRID(s): 4229410 8 DP Barcode: D241198 Subject: Quinclorac. ID#007969
- 00113. Revised Section B. Reduction In PHI For Use On Rice. From: JS tokes To: MJ Nelson Dated: 10/01/98 MRID(s): 44323101Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **24** of **32** DP Barcode: D241204; D248880; D248881 Subject: PP#7F4870. Quinclorac. In/On Grain Sorghum and Wheat. Evaluation of Analytical Method and

Residue Data. From: JStokes To: MJ Nelson Dated: 11/06/9 8 MRID(s): 44322206, 44322207, 44322208, 44322209, 44322211, 44322212, 44322213, 44322214,

44322216, 44583101, 44583102, and 44583103 DP Barcode: D 342446 Subject: Quinclorac

– Request for Establishment of Tolerances on Barley Grain without a U.S.

Registration. Summary of Analytical Chemistry and Residue Data. Pet ition Number 0E6114
. From: M. Doherty To: H. Johnson/J. Tompkins Dated: 9/11/2007 MRID(s): 44817507, 45088301 DP Barcode: D344496 Subject: Quinclorac. Magnitude of the Residue in Wheat and Sorghum Aspirated Grain Fractions. From: G. Otakie To: J Schnackenbeck Dated: 9/25/2008 MRID(s): 45598703 & 45598704

. DP Barcode: D358151 Subject: Quinclorac; Petition for Tolerances and Use on Pasture and Rangeland Grasses. Summary of

Analytical Che mistry and Residue Data. From: G. Otakie To: James Tompkins Dated: 04/30/2009 MRID(s): 45066302 **F. DOCUMENT TRACKING**  RDI: S. Hummel 0 8 / 11 /12 ; RAB4chemists Petition Number: 1E7957 DP#: D397719 and PC Code: 128974, 0 28974Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **25** of **32** Attachment 1. Residue Chem istry Data Requirements **Residue Chem istry**  **Data Requirem ents for Quinclorac**  **GLN Data Requirem ents**  **Current Tolerances**  **(ppm ) [§180.**  **463 ]**  **Additional Data**  **Needed? MRID Nos.**  **860.1200: Directions for Use** NA **860.1300: Nature of the Residue -**  **Plants** NA No 41 063534, 44322207, 44322211 , 44817502 **860.1300: Nature of the Residue -**  **Livestock** NA No 41076104 , 41063535 **860.1340: Residue Analytical Method** Plant and Livestock Commodities NA No 41063537 , 44583103 41063536 **860.1360: Multiresidue Method** 41063541 **8 60.1380: Storage Stability Data**  Plant Commodities NA No 41063544 , 44322214 Livestock Commodities NA No **860.1400: Magnitude of the Residue -**  **Water, Fish and Irrigated Crops** NA NA None **860.1460: Magnitude of the Residue -**  **Food Handling**  NA NA None **860.1 480: Magnitude of the Residue**  **- Meat, Milk, Poultry, Eggs**  Catt le fat, meat, and meat byproducts 0.7/1.5/ 0.05 No 41063545 Hog fat, meat and meat byproducts 0.7/1.5/ 0.05 No N one Milk 0.05 No 41063545 Eggs and the Fat, Meat and Meat Byproducts of Poultry 0 .05 /0.05/0.1/0.05 No 41063546 **860.1500: Crop Field Trials** Rhubarb 0.5 proposed No 48697501 Cranberry 1. 5 proposed No 4869750 2 **Grains** Barley grain (imported) No 44817507 , 45088301 Rice grain, straw 5.0/12.0 No 41063542 , 44323101 Sorghum forage , grain, stover 3.0/6.0/1.0 No 44322212 Wheat forage, grain, hay, straw 1.0/0.5/0.5/0.1 No 44322208, 44322209 , 45066301 Grain, aspirated fractions No 45598703 , 45598704 Pasture/rangeland grasses No 45066302 Comparison of DF formulation of quinclorac to quinclorac DMA salt in rice, sorghum, wheat No 48051901 **860.1520: Processed Food/Feed** Barley No Rice No 41063543 Sorghum No 4432221 3, 44583102 , 44583104 Wheat No 44322210 , 44817501 , **860.1650: Subm ittal of Analytical**  **Reference Standards** NA No None **860.1850: Confined Accum ulation in**  **Rotational Crops** NA No 42294108, 42294109 **860.1900: Field Accum ulation in**  **Rotational Crops** NA No 41781428Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **26** of **32** Attachment 2 Additional information on metabolism from EFED reviews From 3/8//99 review by

R. Mahler and E. Odenkirchen, Quinclorac Herbicide, Environmental Fate and Effects Assessment and Characterization for a Section 3 Use on Wheat and Sorghum 

### Hvdrolysis (161 

## - 1)

. Fifty ppm [3
- 14C] quinclorac was hydroly tically stable in aqueous buffered pH 5, 7, and 9 solutions. After 737 hours, quinclorac comprised > 98% of the applied in the three buffer solutions and was the only [1 4C]compound detected. This study is acceptable. 

### (MRID 40320816) 

### P&Q **degradation in Water** (161
- 2) [3
- '4C]Quinclorac (radio chemical puri ty 99.6%), at 5.4 ppm, degraded slightly (
- 40% of the applied) in a sterile aqueous pH 

### 7 buffer solution that was irradiated for 697 hours using a xenon arc lamp at 25 C. After 697 hours of irradiation, quinclorac comprised 92%
I of the recovered radioactiv ity , an unidentified degradate comprised 1.6%, and 2.7% remained near the origin of the TLC plate. The extrapolated half
- life was 100 day s (note extrapolations beyond the study duration are uncertain). The sensitized half
- life using aceto ne was 52 day s. Th is study is acceptable. 

### (MRID 41063560) Conversely , the photoly

tic half
- lives of non
- radiolabled quinclorac in non
- sterile natural river water and solutions containing activated sewage sludge were, respectively , 5 and 10 day s (not corrected for dark control results, which suggest that between 8
- 12% of degradation would be accounted for processes other than photolysis over a 47
- day incubation). The authors concluded that photolysis was the main route of degradation in these two studies; however, they did n ot identify

any degradates. Furthermore, the length of exposure was only

6 hours/day . Had a longer daily sunlight exposure regime been used, the half

- lives, as determined , may have differed from that reported and may have been less by

at least one
- half, b ased on a ty pical 12
- hour daylight exposure period. This study is supp l emental. (MRID 41063564 ) From Y Donovan, “ **Quinclorac: Section 3 Registrations for New Use**  **on Pasture/ Rangeland :** 

Drinking Water Exposure Assessment , D362085, June 3, 2009. For persist ence, laboratory data indicate that quinclorac is stable to hydroly sis, photoly sis in sterile water, as well as aerobic and anaerobic metabolism in soil. Conversely , quinclorac undergoes rapid photoly sis in non
- sterile rice paddy , natural river waters, an d solutions containing activated sewage sludge (half
- lives of 5
- 10 day s). Photoly sis on soil surface is also a route of dissipation with a mean half life of 141 days. Field studies reviewed to date indicate that quinclorac is moderately persistent (18
- 1 76 day s half
- lives) in terrestrial environment.Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **27** of **32** 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 degradation to 5
- chloro
- 2
- hydroxy
- nicotinic acid, which in turn is metabolized to 5
- chloro
- 2,6
- dihydroxy
- nicotinic acid, 2 hydroxy
- 3
- chloro
- 8
- quin oline carboxylic acid (BH 514 2
- OH), 7
- chloro
- 8
- quinoline carboxylic acid, 8
- quinoline 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 natural s oil 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 concentrations were: BH 514 2
- OH (14.9% TRR), BH 514
- Me ester (7.8% TRR). Parent was found at maximum concentrations of 58.1% TRR. 3. BH 541
- 1 was also reported in the aerobic aquatic metabolism (MRID 42294102), at maximum o f 55.7% of the initial radioactivity after 6 months and 30.8% after 12 months. Adsorption/desorption studies determine that this degradate is less mobile than its parent, with Kd ’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 dissipation studies, at any soil depth. For mobility

in aquatic environment, aquatic field dissipations studies with rice indicate tha t 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 volatilization from soil and water. Bioaccumulation in fish is not expected according to the acceptable fish accumulation study , which showed that after 28 day s of exposure, quinclorac did not accumulate in channel catfish. No BCF val ue was reported (MRID 40320819 and 41063559). Furthermore, the octanol/water partition coefficient (KOW ) of 0.266 also suggests that quinclorac has low potential to bioaccumulate. A detailed assessment of the environmental fate of Quinclorac could be fo und in the “Environmental Fate and Ecological Effects Assessment and Characterization for a Section 3 for Use on Wheat and Sorghum” report dated March 05, 1999 (DP Barcodes: 250179, 248882, 248884, 192866, 231399, and 238400). The chemical structures of q uinclorac and its 2 major metabolites (BH 514
- 1 and BH 514 2
- OH) are shown in Table III.Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **28** of **32 Table III**  **- Chemical Structures of quinclorac and its major metabolites** 

N Cl


### Cl

CO 2 

### H

Qu inc lor ac

N

BH5 14- 1 

### CO 2 

### H

N



### BH 514 2- OH CO 2 

### H OH

ClQuinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **29** of **32 Appendix I:**  

### International Residue Limits

Quinclorac (PC Code 12897 4; Date of Request 7/26/12) Summary of US and International Tolerances and Maximum Residue Limits Residue Definition : US Canada Mexico 1 Codex 40 CFR 180.463 Plant/Livestock: quinclorac , 3,7
- dichloro
- 8
- quinolinecarboxylic acid 3,7
- dichloro
8
- quinolinec arb oxylic acid None
Commodity Tolerance (ppm) /Maximum Residue Limit (mg/kg) US Canada Mexico 1 Codex Barley , grain 2.0 2.0 Cattle, fat 0.7 0.05 Cattle, meat by

products 1.5 0.05 Cattle, meat 0.05 0.05 Egg 0.05 0.05 Goat, fat 0.7 0.05 Goat, meat by

products 1.5 0.05 Goat, meat 0.05 0.05 Grass, forage 150 Grass, hay 130 Hog, fat 0.7 0.05 Hog, meat by

products 0.05 0.05 Hog, meat 0.05 0.05 Horse, fat 0.05 0.05 Horse, meat by

products 1.5 0.05 Horse, meat 0.05 0. 05 Milk 0.05 0.05 Poultry , fat 0.05 0.05 Poultry , meat by

products 0.05 0.05 Poultry , meat 0.05 0.05 Rice, bran 15.0 Rice, grain 5.0 5.0 Sheep, fat 0.7 0.05 Sheep, meat by

products 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 0.1Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **30** of **32** Summary of US and International Tolerances and Maximum Residue Limits Residue Definition : US Canada Mexico 1 Codex Proposed MRLs Lo w growing berries, except strawberries, subgroup 13
- 07 H 1.5 Rhubarb 0.5 MRL s Wi th No US Equivalent Barley , bran 3.5 Completed by : M. Negussie; 07/31/2012 1 Mexico adopts US tolerances and/or Codex MRLs for its export purposes. (b) Section 18 emergency exemptions . Time
- limited tolerances are established for residues of the herbicide quinclorac, including its metabolites and degradates, in or on the commodity in the table in this paragraph. Compliance with the tolerance level specified in this paragraph is to be determined by

mea suring only

quinclorac, 3,7
- dichloro
- 8
- quinolinecarboxylic acid, in or on the commodity . The tolerance expires and is revoked on the date specified in the table in this paragraph. **Commodity Parts per million**  **Expiration/revocation date** Cranberry 15.0 12/31 /12Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **31** of **32 Appendix II**  **OECD MRL CALCULATOR Quinclorac**  **Cranberry US**  **2 x 0.25 lb ai, 60 PHI Quinclorac**  **Residues (mg/kg) Cranberry**  0.550 **US** 0.180 **2 x 0.25 lb ai, 60 PHI** 0.165 0.155 **Total number of data (n)** 5 0.670 **Percentage of censor ed**  **data** 0% **Number of non -**  **censored data** 5 **Lowest residue** 0.155 **Highest residue** 0.670 **Median residue** 0.180 **Mean** 0.344 **Standard deviation (SD)** 0.247 **Correction factor for censoring (CF)** 1.000 **Proposed MRL estimate**

**- Highest residue**  0.670

**- Mean + 4 SD**  1.331

**- CF x 3 Mean**  1.032 **Unrounded MRL** 1.331 **Rounded MRL 1.5**  High uncertainty of MRL estimate. [Small dataset]Quinclorac 1 28974 Summary of Analytical Chemistry and Residue Data DP#: D397719

Page **32** of **32 OECD MRL CALCULATOR**  **Quinclorac Rhubarb**  **US 2 X 0.375 lb ai**  **Quinclorac Residues (mg/kg)**  **Rhubarb** 0.205 **US** 0.173 **2 X 0.375 lb ai** 0.108 0.067 **Total number of data (n)**  4 **Percentage of censored data** 0% **Number of non -**  **censored data** 4 **Lowest residue** 0.067 **Highest residue** 0.205 **Median residue** 0.141 **Mean** 0.138 **Standard d eviation (SD)**  0.062 **Correction factor for censoring (CF)** 1.000 **Proposed MRL estimate**

**- Highest residue**  0.205

**- Mean + 4 SD**  0.388

**- CF x 3 Mean**  0.415 **Unrounded MRL** 0.415 **Rounded MRL 0.5**  High uncertainty of MRL estimate. [Small dataset]