UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460 **OFFICE OF CHEMICA**  **L SA FETY**  **AND POLLUTION PREVENTION**  **MEMORANDUM Date**  **:** November 6 , 2012 **SUBJECT:** Quinclorac: Risk Assessment InSupport of Registration Review and for N ew

Proposed U se on Rhubarb and B erry , low growing, except S trawberry , S ubgroup 13 - 07H. **PC Code:** 128974 , 028974 **DP Barcode:** D4 04794 , D4 04808 **Decision No.:** 459055, 468877 **Registration No. :**  NA **Petition No .:**  1E7957 **Regulatory Action:** Section 3 Registration and Registration Review **Risk A**  **ss essment Typ**  **e :**  Single Chemical/ A ggregate **Case No.:** 7222 **T XR No.:**  NA **CAS No.:** 84087 - 01 - 4 , 84087 - 48 - 9 **MRID No.:** NA **40 CFR:** 180.463 **FROM:** Jessica Kidwell, Risk Assessor

Abdallah Khasawinah, Ph.D., Toxicologist Susan Hummel/Gary

Otaki e, Chemists Bonnie Cropp - Kohlligian, Dietary Exposure Assessor Iv an Nieves, ORE Assessor Risk Assessment Branch IV , Health Effects Division (7509P) **THROUGH:** Elissa Reaves, Ph.D., Branch Chief

Risk Assessment Branch IV Health Effects Division (7509P) **TO:** Wilhelmena Livingston, RM60

Risk Management and Implementation Branch 4 Pesticide Re - Evaluation Division (7508P) Erik Kraft and Kable Davis, PM25 Herbicide Branch, Registration Division (7505P) Barbara Madden , PM5 RIMUERB, Registration Division (7505P)Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **2** of **80** This document provides the Health Effect Division’s (HED’s) risk assessment on quinclorac conducted in support of registration review of currently registered uses including the use of quinclorac dimethylamine , as well as the Albaugh Inc. and the Interregional Research Project No. 4 (IR4) request for propos ed uses of the product QUINCLORAC 4L AG Herbicide (EPA Reg. No. 42750 - 169). Registration is proposed for QUINCLORAC 4L AG Herbicide with the active ingredient quinclorac on rhubarb and berry , low growing, except strawberry , subgroup 13 - 07H .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **3** of **80 Table of Contents**  1.0. Executive Summary ................................ ................................ ................................ ............. 5 2.0. HED Recommendations ................................ ................................ ................................ ...... 8 2.1. Dat a Deficiencies ................................ ................................ ................................ ............. 9 2.2. Tolerance Considerations ................................ ................................ ................................ . 9 2.2. 1. Enforcement Anal ytical Method ................................ ................................ ............... 9 2.2.2. Recommended Tolerances ................................ ................................ ........................ 9 2.2.3. Revisions to Petitioned - For Tolerances ................................ ................................ .. 12 2.2.4. International Harmonization ................................ ................................ ................... 13 2.3. Label Recommendations ................................ ................................ ................................ 13 2.3.1. Recommendations from Residue Chemistry Reviews ................................ ............ 13 2.3.2. Recommendations from Occupational Assessment ................................ ................ 13 2.3.3. Recommendations from Residential Assessment ................................ ................... 13 3.0. Introduction ................................ ................................ ................................ ........................ 13 3.1. Chemical Identity ................................ ................................ ................................ ........... 13 3.2. Phy sical/Chemical Characteristics ................................ ................................ ................. 14 3.3. Pesticide Use Pattern ................................ ................................ ................................ ...... 15 3.4. Anticipated Exposure Pathway s ................................ ................................ ........................ 21 3.5. Consideration of Environmental Justice ................................ ................................ ........ 21 4.0. Hazard Characterization and Dose - Response Assessment ................................ ................ 22 4.1. Toxicology

Studies Available for Anal ys is ................................ ................................ ... 22 4.2.1. Dermal Absorption ................................ ................................ ................................ .. 23 4.4. Safety

Factor for Infants and Children (FQPA Safety Factor) ................................ ....... 24 4.4.1. Completeness of the Toxicology Database ................................ ............................. 24 4.5. Toxicity

Endpoint and Point of Departure Selections ................................ .................... 25 4.5.1. Dose - Response Assessment ................................ ................................ .................... 25 4.5.2. Recommendation for Combining Routes of Exposures for Risk Assessment ........ 26 4.5.3. Cancer Classification and Risk Assessment Recommendation .............................. 26 4.5.4. Summary

of Points of Departure and Toxicity Endpoints Used in Hum an Risk Assessment ................................ ................................ ................................ ............................ 26 4.6. In cident Reports ................................ ................................ ................................ ............. 29 5.0. Dietary

Exposure and Risk Assessment ................................ ................................ ............ 31 5.1. Metabolite/Degradate Residue Profile ................................ ................................ ........... 31 5.1.1. Summary

of Plant and Animal Metabolism Studies ................................ ............... 31 5.1.2. Summary

of Environmental Degradation ................................ ............................... 33 5.1.3. Comparison of Metabolic Pathway s ................................ ................................ ....... 3 4 5.1.4. Residues of Concern Summary and Rationale ................................ ........................ 34 5.2. Food Residue Profile ................................ ................................ ................................ ...... 34 5.3. Water Residue Profile ................................ ................................ ................................ .... 37 5.4. Dietary

Risk Assessment ................................ ................................ ................................ 40 5.4.1. Description of Residue Data Used in Dietary Assessment ................................ ..... 40Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **4** of **80** 5.4.2. Percent Crop Treated Used in Dietary Assessment ................................ ................ 41 5.4.3. Acute Dietary

Risk Assessment ................................ ................................ .............. 41 5.4.4. Chronic Dietary

Risk Assessment ................................ ................................ .......... 41 5.4.5. Cancer Dietary

Risk Assessment ................................ ................................ ............ 42 5.4.6. Summary

Table ................................ ................................ ................................ ....... 42 6.0. Residential (Non - Occupational) Exposure/Risk Characterization ................................ .... 43 6.1. Residential Handler Exposure ................................ ................................ ........................ 43 6.2. Residential Post - Application Exposure ................................ ................................ .......... 45 6.2.3. Residential (Non - occupational) post - application inhalation ................................ ...... 45 6.2.4. Residential (Non - Occupational) Post - Application Dermal and Incidental Oral ........ 45 6.3. Combined Residential Risk Estimates (Multiple Exposure Scenarios) ......................... 46 6.4. Residential Risk Estimates for Use in Aggregate Assessment ................................ ...... 46 6.5. Residential By stander Post - application Inhalation Exposure ................................ ............ 47 6.6. Spray

Drift ................................ ................................ ................................ ......................... 47 7.0. Aggregate Exposure/Risk Characterization ................................ ................................ ....... 48 7.1. Acute Aggregate Risk ................................ ................................ ................................ ......... 48 7.2. Short - Term Aggregate Risk ................................ ................................ ................................ 48 7.3. Intermediate - Term Aggregate Risk ................................ ................................ .................... 49 7.4. Chronic Aggregate Risk ................................ ................................ ................................ ...... 49 7. 5. Cancer Aggregate Risk ................................ ................................ ................................ ....... 50 7.6. Cumulative Exposure/Risk Characterization ................................ ................................ ...... 50 8.0. Occupational Exposure/Risk Characterization ................................ ................................ .. 50 8.1. Short - /Intermediate - /L ong - Term/Cancer (if needed) Handler Risk ................................ .... 50 8.2. Short - /Intermediate - /L ong - Term/Cancer (if needed) Post - Application Risk ...................... 57 8.2.1. Dermal Post - application Risk ................................ ................................ ........................... 57 8.2.2. Inhalation Post - application Risk ................................ ................................ ....................... 57 9.0. References ................................ ................................ ................................ .......................... 58 Appendix A. Toxicology Profile and Executive Summaries ................................ ....................... 60 A.1 Toxicology

Data Requirements ................................ ................................ ...................... 60 A.2 Toxicity

Profiles ................................ ................................ ................................ ............. 61 A.3 Hazard Identification and Endpoint Selection ................................ ............................... 65 A.4 Executive Summaries ................................ ................................ ................................ ..... 69 Appendix B. Review of Human Research ................................ ................................ ................... 78 Appendix C: International Residue Limits ................................ ................................ ................... 79Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **5** of **80 1.0.**  **Executive Summary** Q uinclorac is an herbicide for the selective post - emergent control of various annual grasses and broadleaf weeds. It is adsorbed via the root s ys tem and partiall y through the foliage and acts as an inhibitor of cell wall sy nthesis . Quinclorac is currentl y formulated into a variety of product formulation s including; dry flowable, wettable powder, ready- to - use, granular, emulsifiable concentrate, flowable concentrate, and liquid formulations . Two new agricultural uses of quinclorac have been proposed for the dry flowable fo rmulation of the end - use product QUINCLORAC 4L AG Herbicide (EPA Reg. No. 42750 - 169) , a 3.8 lb a . i . /gallon liquid formulation. The new uses include the following crops; low growing berries, except strawberries, subgroup 13 - 07H, and rhubarb. The maximum s ingle application rates for the proposed uses are 0.25 and 0.37 lb ai/A for low growing berries, except strawberries, subgroup 13 - 07H, and rhubarb, respectivel y . QUINCLORAC 4LAG Herbicide may be applied as a foliar spray using ground equipment only . The variety of end - use products containing quinclorac is currentl y registered on rice, sorghum, and wheat . In addition to agricultural crops, quinclorac is also registered for : agricultural fallow/idleland/conservation reserves; nonagricultural uncultivate d areas/soils; grass forage/fodder/hay ; grasses grown for seed; pastures and rangelands; agricultural and nonagricultural rights of way /fencerows/hedgerows; agricultural uncultivated areas; utility poles/rights of way ; airports/landing fields; ornamental s od farms; commercial/industrial lawns. Additionally , quinclorac is registered for use b y commercial applicators and homeowners on lawns, parks, in and around ornamentals, and golf courses. A new ph ys ical form of quinclorac (EPA Reg. No. 7969 - 272) has rec entl y been registered: Drive XLR - 8 (Reg. No 7969 - 272), Paramount L Herbicide (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 (dimethylamine) salt forms of quinclorac. Thes e products were not proposed for the new uses of quinclorac, proposed in the current petition, but are registered for use on rice and ornamental turf. Hazard Quinclorac toxicity

in experimental animals is observed mostly at doses above 150 mg/kg/day following subchronic and chronic exposures. Subchronic exposure to quinclorac caused decreased body weight gains, increased water intake, increased liver enzymes and focal chronic interstitial nephritis (rats). Chronic toxic effects include body weight decrement, increase in kidney and liver weights, and hydropic degeneration of the kidney s (dogs). At high doses, chronic toxicity

also includes increased incidences of pancreatic acinar cell hy perplasia and adenomas . Neurotoxic effects were not observed in any of the acute, subchronic and chronic studies with quinclorac. There was no increased qualitative or quantitative fetal or offspring susceptibility

in the prenatal developmental studies in rats or rabbits or postnatal reproduction study in rats . There are no mutagenicity concern s . Quinclorac was classified in 1992 b y the HED Cancer Peer Review committee (CPRC) as a group D carcinogen - not classifiable as to human carcinogenicity- based on recommendation b y the EPA Scientific Advisory Panel. Based on the classification, a quantific ation of cancer risk is not warranted because the chronic RfD willQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **6** of **80** adequatel y account for all chronic effects, including carcinogenicity , that may result from exposure to quinclorac. Quinclorac (technical grade material) has a low order of acute toxicity as demonstrated by Toxicity Category I II b y the oral, dermal, and inhalation routes. The chemical is a mild eye irritant, is not a skin irritant, but was positive for dermal sensitization. Endpoints and Uncertainty Factors for Risk Assessment HED reviewe d the toxicity database for quinclorac as well as the most recent risk assess ment (D359759, Y. Donovan et al , 8/5/2009) and concluded that no changes in the points of departure (PODs ) or FQPA SF (1x) are warranted. Since the last risk assessment the immunotox i c i ty study in mice was submitted and reviewed. The results of this study did not impact the overall risk assessment. Since the last risk assessment, the HED Hazard and Science Policy Council ( HASPOC ) waived the requirement for a neurotoxicity battery ( acute and subchronic neurotoxicity

studies ) and a DNT study . Chemistry Permanent tolerances have been established for residues of quinclorac per se in/on barley , rice, sorghum and wheat at levels ranging from 0.1 ppm in wheat straw to 1200 ppm in aspirated 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. In addition , there is a tolerance for quinclorac resid ues on cranberry

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. The qualitative nature of quinclorac residues in plants was considered adequately understood for the currently

registered crops, based upon the metabolism studies on rice, sorghum, and wheat. Further metabolism data may be needed if uses are further expanded. The qualitative nature of quinclorac residues in livestock is also understoo d based upon the adequate goat and poultry metabolism studies. The Agency had concluded that parent is the onl y residue of concern in both plant and livestock commodities for purposes of the tolerance expression and risk assessment. An adequate enforcement method is available for enforcing quinclorac tolerances on plants and livestock, a GC/ECD method that uses methylation with diazomethane. There is available FDA multi - residue method ( MRM) testing data that indicate that quinclorac is completely recovered using Protocol B . Adequate cattle and poultry feeding studies are available and support the use of quinclorac. Adequate rotational crop studies are available and support the use of quinclorac.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **7** of **80** Dietary (food+water) Exposure and Risk The Environmental Fate and Effects Division (EFED) completed a drinking water assessment in support of human health risk assessment. The current assessment is performed according to current EFED guidance and up - to - date models including the Tier II surface water model (PRZM/EXAMS) for all uses of quinclorac, except cranberries and rice . Screening - level Tier I modeling was used to estimate surface w ater concentrations for use on cranberry (provisional cranberry model) and rice (Tier I rice model) because the current Tier II model is not parameterized for those uses. The Tier I SCI - GROW model was used to estimate groundwater concentrations for all us es. Surface water EDWCs (acute = **511 μg/L** and chronic = **511 μg/L** ) resulting from use on rice supersede previousl y recommended EDWCs. The recommended groundwater EDWC has not changed ( **29 μg/L** for acute and chronic exposure). Both the acute and chronic dietary assessments are highl y conservative, and assume 100% crop treated (%CT), along with tolerance - level residues for all agricultural commodities. Default processing factors from DEEM 7.81 were used (for dried beef and cranberry juice) in the anal ys es. The acute (food + water) dietary risk estimate at the 95 th percentile of exposure is 1 .6 % of the acute population adjusted dose (aPAD) for females age 13 to 49 . This is the only population subgroup for which an acute endpoint was selected. The c hronic (food + water) dietary risk estimates are less than or equal to 8 .9 % of the chronic population adjusted dose (cPAD) for all population subgroups. All Infants < 1 year of age is the most highly- exposed subgroup, utilizing 8 .9 % of the cPAD, while th e general US population utilizes 3 .6 % of the cPAD. Occupational Exposure/Risk The occupational handler assessment was completed assuming the maximum label application rate from the list of end - use products for each crop. The labels allow for applicati on via aerial, groundboom, chemigation, backpack, manuall y- pressurized handwand, mechanicall ypressurized handgun, trigger- spray bottle, belly

grinder, rotary

spreader, and tractor - drawn spreader equipment. Based on the activity use pattern, the duration o f exposure is expected to be short - term (ST; 1 to 30 day s) and intermediate - term (IT; 1 to 6 months) for occupational scenarios; long - term exposures (greater than 6 months) are not anticipated based on the proposed use pattern. No dermal endpoint was sel ected the refore o nl y inhalation exposure was quantified . For the inhalation route of exposure, the same points of departure were chosen for short - and intermediate - term exposures; therefore, risk estimate s are the same for all durations of exposure. An estimated short - and intermediate - term inhalation NOAEL of 7 0 mg/kg/day for quinclorac was selected from a developmental rabbit toxicity study . Therefore, for risk characterization purposes, s ince no inhalation absorption data are available, toxicity by the inhalation route is considered to be equivalent to the estimated toxicity by the oral route of exposure . The proposed label requires long - sleeved shirt, long pants, shoes plus socks, and chemical - resistant gloves as personal protective equipment (PPE) for all applicators and other handlers. All risk estimates of the proposed uses for occupational handler s are above the target MOE of 100. Occupational handler risk estimates resulted in inhalation MOEs ranging from 4800 - 940,000 for proposed new uses and 1000 - 1,100,000 for registered uses. The occupational handler inhalation risk estimates above 100 do not exceed HED’s level of concern.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **8** of **80** Based on the Agency's current practices, a quantitative non - cancer occupational post - application inhalation exposure assessment was not performed for quinclorac at this time ; handler inhalation exposure estimates are considered to be protective of occupati onal post - application inhalation exposure scenarios. If new policies or procedures are put into place, the Agency may revisit the need for a quantitative occupational post - application inhalation exposure assessment for quinclorac. There is potential for dermal exposure during occupational post - application activities , such as crop maintenance activities, scouting, irrigation, and harvesting . However, since no dermal (short - or intermediate - term) toxicological endpoints were identified, an assessment of po st application exposure and risk cannot be quantified. Residential Exposure/Risk There are no proposed residential uses at this time; however, there are existing uses for quinclorac on residential, non - residential turf (i.e., athletic fields, cemeteri es, parks, etc.) and sod farms to control several broadleaf and grass weeds that have been reassessed in this document to reflect updates to HED’s 2012 Residential SOPs, along with policy changes for body

weight assumptions . Since individuals can potentially be exposed to treated turf , a residential post application assessment was previousl y conducted (T. Moriarty; 08/13/2008; D342993). The revision of residential exposures will impact the human health aggregate risk assessment for quinclorac . P ost - application exposure and risk estimates resulted in i nhalation MOE s ranging from 3600 - 250,000,000. These MOEs were greater than the LOC of 100, and , therefore , were not of concern. Aggregate In general, aggregate exposures are calculated b y s umming diet ary (food and drinking water) and residential exposures (residential or other non - occupational exposures). HED reviewed all residential sources of exposure to determine which residential exposure scenarios would be appropriate to combine with dietary expo sure for an aggregate risk assessment. The only applicable exposure pathway s are inhalation (for adult handlers) and incidental oral (for post application exposure to children). The short - term aggregate MOE s for the adult handlers and the children were 2 1 00 and 1 6 00, respectivel y , which are above the LOC of 100 and , therefore , not of concern. An intermediate - term adverse effect was identified; however**,** quinclorac is not registered for any use patterns that would result in intermediate - term residential exposure . Therefore, an intermediate - term aggregate risk assessment was not performed nor required. Additionally , aggregate acute and chronic (food and water) exposures were ≤100% the cPAD for all population subgroups as a result of all registered/proposed uses. Thus, acute and chronic aggregate exposure to quinclorac is not of concern. **2.0. HED**  **Recommendations** HED is recommending in favor of registration of quinclorac on the requested crops and establishment of tolerances as summarized in Table 2.2.3 . HED has evaluated current uses of quinclorac and its dimethylamine salt . Tolerance changes are recommended due to recalculation of the dietary

burden and for harmonization.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **9** of **80 2.1.**  **Data Deficiencies** Toxicology: None Residue Chemistry:

• Data on catfish and crayfish are required, or the label must prohibit use of treated water from rice and cranberry fields for aquaculture (See Section 2.3) . For registration review, data are required or the PM must ensure that all quinclorac labels with us es on rice and cranberry contain such a restriction.

• F urther expansion of the use of quinclorac to other commodities grown on larger acreages than rhubarb and cranberry

will trigger a requirement of additional metabolism data.

• For the current petition, Albaugh must suppl y the Pesticide Repository with anal ytical standards for quinclorac and the quinclorac methylester which is used in the current enforcement method .

• For registration review, an anal ytical standard for the quinclorac DMA salt must be submitted to the EPA National Pesticide Standards Repository . ORE: None. **2.2. Tolerance Considerations**  **2.2.1. Enforcement Analytical Method**  Adequate anal ytical methods (GC/ECD) are available f o r enforcing quinclorac tolerances on plant (BASF Method A8902; MRID# 41063537) and livestock (BASF Method 268/1; MRID# 41063536) commodities. 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 LOQ of both methods is 0.05 ppm for all matrices. In BASF Method 268/1, used for both plant and animal matrices, samples are extracted with acetone and dichloromethane and redissolved in acetone/h exane. An aliquot is subjected to GC chromatography using a DB - 5 column and electron capture detection. Methylated standard is used for quantitation. The LOD was reportedly 0.05 ppm, but this was also the lowest level validated. Quinclorac is detected b y FDA Multiresidue Protocol B, but not the other FDA Multiresidue Method (M RM ) Protocols.

**2.2.2. Recommended Tolerances**  The current tolerance expression for quinclorac is:

“ Tolerances are 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 theQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **10** of **80** tolerance levels specified in this paragraph is to be determined b y measuring onl y quinclorac, 3,7 - dichloro - 8 - quinolinecarboxylic acid, in or on the commo dity . ” The tolerance expression is in accord with our current guidance on tolerance expressions. Current Petition: Tolerance recommendations for the current petition (IE7957) on low growing berries, except strawberries, subgroup 13 - 07H, and rhubarb are i n the first two lines of Table 2.2. 2 . Tolerance Consideration for Registration Review: 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, recentl y reviewed data indicate that a tolerance on AGF is not necessary (DP# 344496, G. Otakie, 9/25/08). Perm anent 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. 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, with the exception s of the tolerances on poultry meat b yproducts and hog fat and meat b yproducts . Based on th e recalculated Maximum Dietary Burdens ( 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 b yp roducts and hog fat and meat by products. In addition, HED notes that the Agency no longer considers rice straw to be a significant 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. The use of the DMA salt of quinclorac will not affect the established tolerances for quinclorac on rice, grain sorghum, and wheat. **Table 2.2. 2**  **Toleranc e Summary for Quinclorac.**  **§ 180.463**  Commodity Current/Proposed Tolerance (ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition Berry, low

growing, except straw

berry , 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 level based on OECD tolerance calculation procedures.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **11** of **80 Table 2.2.**  **2 Toleranc**  **e Summary for Quinclorac. §**  **180.463** Commodity Current/Proposed Tolerance (ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition **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 tolerance 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 harmonized with Canada. Hog, meat 0.05 0.05 Horse, fat 0.7 0.7 Horse, meat by

products 1.5 1.5 Horse, meat 0.05 0.05 Milk 0.05 0.05 Poultry, fat 0.05 0.05Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **12** of **80 Table 2.2.**  **2 Toleranc**  **e Summary for Quinclorac. §**  **180.463** Commodity Current/Proposed Tolerance (ppm) Recommended

Tolerance (ppm) Comments; Correct Commodity

Definition Poultry, meat byproducts 0.1 0.05 Based on the residue data from the poultry feeding and the calculated 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 by

products 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 0.1

**2.2.3. Revisions to Petitioned**  **- For Tolerances**  **and Existing Tolerances** Current Petition: Revisions are recommended to petitioned - for tolerances due to the use of the OECD tolerance calculation procedures. The recommended changes are documented in Table 2.2. 2 . Tolerance Revisions for Registration Review: Revisions to current tolerances for registration review are documented in Table 2.2. 2 . Some tolerances are being removed because the commodity

is no longer regulated. The tolerance for Grain, Aspirated Fractions is being removed because it it not necessary . Tolerances on meat, poultry , milk, and eggs are being revised based on a recalcul ation of the dietary burden, and to harmonize internationall y.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **13** of **80 2.2.4.**  **International Harmonization** CODEX has not established any established maximum residue limits (MRLs) for quinclorac. Canada has established maximum residue limits (MRL s) for quinclorac on sel e cted agricultural commodities but no t the commodities in the current petition . Recommendations for harmonization are in Table 2.2. 2 for Registration Review. **2.3. Label Recommendations**  **2.3.1. Recommendations from Residue**  **Chemistry Reviews** 

• Cranberry

i s an aquatic crop, and as such, a label restriction is needed reg arding the use of treated rice and cranberry fields for aquaculture. Alternativel y, 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.

• For Registration Review, the PM must ensure that all labels for quinclorac on rice and cranberry contain a label restriction restricting the use of treated rice and cranberry fields for aquaculture . **2.3.2. Recommendations**  **from Occupational Assessment** The proposed label requires long - sleeved shirt, long pants, shoes plus socks, and chemical resistant gloves as personal protective equipment (PPE) for all applicators and other handlers. The 12 hour REIwhich is currently o n the label is adequate for the new crop uses with the product QUINCLORAC 4LAG Herbicide .

**2.3.3. Recommendations f**  **rom Residential**  **Assessment** None. **3.0. In**  **troduction 3.1.**  **Chemical Identity**  Quinclorac is a herbicide for the selective post - emergent control of various annual grasses and broadleaf weeds. Quinclorac is adsorbed via the root sy stem and partially through the foliage and acts as an inhibitor of cell wall s ynthesis. The nomenclature of quinclorac and quinclorac DMA salt are summarized in Table 3.1. **Table 3.1. Quinclorac and Quinclorac (DMA salt) Nom**  **enclature.** Com pound

N Cl Cl

O O HQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **14** of **80 Table 3.1.**  **Quinclorac and Quinclorac (DMA salt) Nom enclature.**  Common name Quinclorac, Com pany experimental name BAS 514 34H IUPAC name 3,7 - dichloroquinoline - 8 - carboxylic acid CAS name 3,7 - dichloro - 8 - quinolinecarboxylic acid CAS registry number 84087 - 01 - 4 Molecular weight 242.1 End - use product (EP) Drive® 75 DF Com pound

**N Cl**  **Cl**

**O O**  **N H**  **C H**  **3 C**  **H 3**  **H +** 

Common name Quinclorac, DMA salt Com pany experimental name BAS 514 51H IUPAC name 3,7 - dichloroquinoline - 8 - carboxylic acid, DMA salt 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 **3.2. Physical/Chemical Characteristics**  The phy sicochemical properties of the technical grade quinclorac are summarized in Table 3.2. 1. Only several p hy sicochemical properties of the DMA salt of quinclorac are available (Table 3.2.2) . The ph ys ical and chemical properties of quinclorac indicate that it is unlikely to volatilize and has low potential to accumulate in fatty tissues. In addition, 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 q uinclorac TGAI and the UV/Vis spectra and dissociation constant of quinclorac DMA were presented . The results of the study s how that in aqueous solutions, the chemical form of the quinclorac dimethylamine salt is the same as that of the quinclorac acid fo rm.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **15** of **80 Table**  **3. 2.**  **1 Physicochemical 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, pKa 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 48051092 **Table 3.2**  **. 2**  **Physicochemical 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, pKa 4.33 ± 0.15 (Temperature 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 **3.3. Pesticide Use Pattern**  Proposed new uses. IR - 4 is proposing use of the Quinclorac 4 - L AG (Reg. No. 42750 - 169), registered to Albaugh, In c., containing 3.8 lb quinclorac/gallon, in connection with the current petition.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **16** of **80 Table 3**  **.3.1 . Summary of Directions for Proposed Use of Quinclorac on Low Growing Berries (Crop Sub**  **- Group 13**  **- 07H), Except Strawberries, and Rhubarb.**  **Applic. Timing, Type, and Equip.**  **Form ulation** 

**[EPA Reg. No. 42750**  **- 169]**  **Max. Single**

**Application Rate**  **(lb a i/A)**  **Max. No.**

**Applic. per Season**  **Max. Seasonal**

**Application Rate (lb ai/A)**  **PHI**

**(days) Use Directions and** 

**Limitations Low Growing Berries (Crop Sub**  **- Group 13**  **- 07H), Except Strawberries**  Foliar; Ground. QUINCLORA

C 4L AG Herbicide 40% ai, Dry Flowable (3.8 lb ai/gal) 0.25 lb ai/A

(8.4 fl oz/A) 2 0.50 lb ai/A (16.8 fl oz/A) 60 Re - treatment Interval = 30 days. Ground application (foliar) only. Do not apply by air. Do not apply to irrigation ditches. Crop oil concentrate permitted. **Rhubarb** Foliar; Ground. QUINCLORA

C 4L AG Herbicide 40% ai, Dry Flowable (3.8 lb ai/gal) 0.37 lb ai/A

(12.6 fl oz/A) 2 0.74 lb ai/A (25.2 fl oz/A) 30 Re - treatment Interval = 30 days. Ground application (foliar) only. Do not apply by air. Do not apply to irrigation ditches. Crop oil concentrate permitted. Maximum Single Application Rate for Lo w Growing Berries (Crop Sub - Group 13 - 07H), Except Straw berries (lb ai/A) = ( 8.4 fl oz/A) ( 3.8 lb ai/gal)(1 gal/128 fl oz) = 0.25 lb ai/A. Maximum Single Application Rate for Rhubarb (lb ai/A) = (1 2.6 fl.oz/A)( 1 gal/1 128 fl.oz ) ( 3.8 lb ai/gal) = 0. 37 lb ai/A. 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 registered for use on rice, grain sorghum, and wheat. Table 3.3.3 provides use sites and maximum application rates for the existing uses for quinclorac. Please refer to S ection 2.3 for recommended modifications to the proposed label.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **17** of **80 Table 3.3.2**  **. Summary of Quinclorac Registered Uses Assessed Under Registration Review** 

**Comm odity**  **Form****** **ulation Product Nam**  **e**

**(EPA Reg. No.) Application**  **Equipment Max.** 

**Single App Rate**  **(lb ai/A) PHI** 

**(days)**

Rice DF 279 - 3366; 34704 - 920; 42750 - 88; 66222 - 160; 7969 - 222; 7969 - 313; 80289 - 14 Aerial; Groundboom 0.503 309 L 42750 - 169; 71085 - 26; AR080007; AR120003 0.47 WSP 7969 - 93 0.5 Sorghum and Wheat DF 7969 - 152; 7969 - 113; 66222 - 160; 42750 - 131 0.375 L 42750 - 169; 42750 - 171 0.35 Agricultural fallow/idleland/conservation reserves; Nonagricultural uncultivated areas/soils; Grass forage/fodder/hay; Grasses grown for seed; Pastures and Rangelands DF 7969 - 113; 42750 - 131; 7969 - 152 Aerial; Groundboom 0.75 40 L 42750 - 169; 42750 - 171 0.75

Agricultural and nonagricultural rights of way/fencerows/hedgerows; Agricultural uncultivated areas; Utility poles/rights of way DF 42750 - 131; 83070 - 9; 7969 - 130; 7969 - 113; 66222 - 160; 42750 - 131; 228 - 592 Backpack; Mechanically pressurized Handgun 0.75

(0.15 lb ai/gal) *

7 - 309 L 7969 - 267; 70506 - 282; 42750 - 220; 42750 - 172; 42750 - 171; 42750 - 169; 228 - 705; 228 - 595; 228 - 531; 228 - 423; 2217 - 946; 2217 - 919; 2217 - 901; 2217 - 888; 2217 - 886; 42750 - 169; 42750 - 171 1.48 (0.296 lb ai/gal) * G 2217 - 927; 2217 - 964 Rotary Spreader 0.68 Airports/landing fields DF 228 - 592; 7969 - 130 Backpack; Manually pressurized 0.75

(0.15 lb ai/gal) * NS 3Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **18** of **80 Table 3.3.2**  **. Summary of Quinclorac Registered Uses Assessed Under Registration Review** 

**Comm odity**  **Form****** **ulation Product Nam**  **e**

**(EPA Reg. No.) Application**  **Equipment Max.** 

**Single App Rate**  **(lb ai/A) PHI** 

**(days)** L 228 - 531; 228 - 705; 42750 - 172; 42750 - 220; 70506 - 282; 7969 - 267 Handwand; Mechanically pressurized Handgun 0.75

(0.15 lb ai/gal) *

Commercial/industrial lawns DF 228 - 592; 279 - 3355; 66222 - 160; 7969 - 130; 83070 - 9 Backpack; Manually pressurized Handwand; Mechanically pressurized Handgun 1.4

(0.28 lb ai/gal) *

NS L 7969 - 267; 70506 - 282; 42750 - 220; 42750 - 172; 228 - 705; 228 - 595; 228 - 531; 228 - 423; 2217 - 946; 2217 - 919; 2217 - 901; 2217 - 888; 2217 - 886 0.78 (0.156 lb ai/gal) * G 2217 - 927; 2217 - 964 Belly grinder; Rotary spreader 0.68 RTU 228 - 594 Trigger - spray bottle 0.76

(0.0172 lb ai/bottle) *

Ornamental la wns and turf DF 83070 - 9; 7969 - 130; 66222 - 160; 42750 - 90; 228 - 592 Backpack; Manually pressurized Handwand; Mechanically pressurized Handgun 0.75

(0.15 lb ai/gal) *

NS L 7969 - 267; 70506 - 282; 42750 - 172; 239 - 2713; 228 - 705; 228 - 704; 228 - 595; 228 - 423; 2217 - 946; 2217 - 919; 2217 - 901; 2217 - 888; 2217 - 886 0.78 (0.156 lb ai/gal) *

G 2217 - 927; 2217 - 964; 538 - 296 Hand dispersal; Belly grinder; Cup; Rotary spreader; Spoon 0.68 RTU 228 - 594; 228 - 703 Trigger - spray bottle 0.76

(0.0172 lb ai/bottle) *Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **19** of **80 Table 3.3.2**  **. Summary of Quinclorac Registered Uses Assessed Under Registration Review** 

**Comm odity**  **Form****** **ulation Product Nam**  **e**

**(EPA Reg. No.) Application**  **Equipment Max.** 

**Single App Rate**  **(lb ai/A) PHI** 

**(days)**

Recreation area and residential lawns DF 83070 - 9; 7969 - 130; 66222 - 160; 279 - 3355; 228 - 592 Backpack; Manually pressurized Handwand; Mechanically pressurized Handgun 1.4

(0.28 lb ai/gal) *

NS L 7969 - 267; 72155 - 86; 70506 - 282; 42750 - 220; 42750 - 172; 228 - 705; 228 - 704; 228 - 595; 228 - 531; 228 - 423; 2217 - 954; 2217 - 946; 2217 - 945; 2217 - 939; 2217 - 938; 2217 - 919; 2217 - 901; 2217 - 896; 2217 - 894; 2217 - 888; 2217 - 886; 2217 - 885; 0.78 (0.156 lb ai/gal) *

G 2217 - 92 7; 2217 - 963; 2217 - 964 Belly grinder; Rotary spreader 0.68 RTU 2217 - 887; 2217 - 917; 2217 - 918; 2217 - 953; 228 - 594; 228 - 703; 239 - 2689 Trigger - spray bottle 0.76

(0.0172 lb ai/bottle) *

Ornamental sod farms (turf) DF 83070 - 9; 7969 - 130; 66222 - 160; 42750 - 90; 279 - 3355; 228 - 592 Aerial; Groundboom; Chemigation 1.4 90 L 70506 - 282; 42750 - 220; 42750 - 172; 228 - 705; 228 - 595; 228 - 531; 228 - 423; 2217 - 946; 2217 - 919; 2217 - 901; 2217 - 888; 2217 - 886 0.78 RTU 228 - 594 Trigger - spray bottle 0.76 Golf course turf DF 42750 - 90; 228 - 592; 279 - 3355; 83070 - 9; 7969 - 130; 66222 - 160; Groundboom; Mechanically pressurized 1.4 NSQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **20** of **80 Table 3.3.2**  **. Summary of Quinclorac Registered Uses Assessed Under Registration Review** 

**Comm odity**  **Form****** **ulation Product Nam**  **e**

**(EPA Reg. No.) Application**  **Equipment Max.** 

**Single App Rate**  **(lb ai/A) PHI** 

**(days)**

L 2217 - 886; 2217 - 888; 2217 - 901; 2217 - 919; 2217 - 946; 228 - 423; 228 - 531; 228 - 595; 228 - 705; 42750 - 172; 42750 - 220; 70506 - 282; 7969 - 267 Handgun 0.78

G 2217 - 964; 2217 - 927 Tractor - draw n Spreader; Rotary spreader 0.68 RTU 228 - 594 Trigger - spray bottle 0.76Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **21** of **80 3.4.**  **Anticipated Exposure Pathways** The Registration Division has requested an assessment of human health risk to support the proposed new use s of quinclorac. The Pesticide Re - Evaluation Division also has requested an assessment for registration review. The variety of end - use products containing quinclorac currentl y registered is as follows; rice, sorghum, and wheat. In additio n to agricultural crops, quinclorac is also registered for: agricultural fallow/idleland/conservation reserves; nonagricultural uncultivated areas/soils; grass forage/fodder/hay ; grasses grown for seed; pastures and rangelands; agricultural and nonagricult ural rights of way

/fencerows/hedgerows; agricultural uncultivated areas; utility poles/rights of way ; airports/landing fields; ornamental sod farms; commercial/industrial lawns. Additionally, quinclorac is registered for use b y commercial applicators and homeowners on lawns, parks, in and around ornamentals, and golf courses. The new uses include the following crops; low growing berries, except strawberries, subgroup 13 - 07H, and rhubarb. Humans may

be exposed to quinclorac in food and drinking water, s ince quinclorac may be applied directl y to growing crops and application may result in quinclorac reaching surface and ground water sources of drinking water. In the occupational and residential setting s , inhalation exposure is expected to be of short - an d intermediate term durations based on the activity use pattern. L ong - term exposures (greater than 6 months) are not anticipated based on the proposed use pattern. No dermal endpoint was selected, therefore, o nly inhalation exposure was quantified . In cidental oral residential exposures (short - term only) are also expected. Risk assessments have been previousl y prepared for the existing uses of quinclorac. This risk assessment considers all of the aforementioned exposure pathways based on the prop osed new u ses of quinclorac, but also considers the existing uses as well, particularl y for the dietary exposure assessment. **3.5. Consideration of Environmental Justice**  Potential areas of environmental justice concerns, to the extent possible, were considered in thi s human health risk assessment, in accordance with U.S. Executive Order 12898, "Federal Actions to Address Environmental Justice in Minority Populations and L ow - Income Populations," (htt p://www.eh.doe.gov/oepa/guidance/justice/eo12898.pdf . As a part of every

pesticide risk assessment, OPP considers a large variety of consumer subgroups according to well - established procedures. In line with OPP policy, HED estimates risks to population s ubgroups from pesticide exposures that are based on patterns of that subgroup’s food and water consumption, and activities in and around the home that involve pesticide use in a residential setting. Extensive data on food consumption patterns are compiled by the USDA under the Continuing Survey of Food Intake by Individuals (CSFII) and are used in pesticide risk assessments for all registered food uses of a pesticide. These data are anal yz ed and categorized by subgroups based on age, season of the ye ar, e thnic group, and region of the country . Additionally , OPP is able to assess dietary

exposure to smaller, specialized subgroups and exposure assessments are performed when conditions or circumstances warrant. Whenever appropriate, non - dietary exposures ba sed on home use of pesticide products and associated risks for adult applicators and for toddlers, youths, and adults entering or playing on treated areas post - application areQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **22** of **80** evaluated. Further considerations are currentl y in development as OPP has commi tted resources and expertise to the development of specialized software and models that consider exposure to by standers and farm workers as well as lifestyle and traditional dietary patterns among specific subgroups. **4.0. Hazard Characterization and Dose**  **- Resp**  **onse Assessment** HED reviewed the toxicity database for quinclorac as well as the most recent risk assess ment which was conducted in association with the new use on pasture/rangeland (D359759, Y. Donovan et al , 8/5/2009) and concluded that no changes in the points of departure (PODs ) or FQPA SF (1x) are warranted. Since the last risk assessment the immunotox i c i ty study in mice was submitted and reviewed (TXR 0052889 ) . The results of this study did not impact the overall risk assessment. **4.1. Toxicology Stu**  **dies Available for Analysis** The toxicology

database for quinclorac is adequate for evaluating and characterizing its toxicity and selecting endpoints for purposes of risk assessment . Studies considered for this assessment include acute lethality

(oral, dermal and inhalation routes), primary eye and dermal irritation, dermal sensitization, subchronic oral toxicity (rat and mouse), rat 21 - day dermal toxicity, dog chronic toxicity, rat combined chronic toxicity /carcinogenicity, mouse carcinogenicity, develo pmental toxicity

(rat and rabbit), rat two - generation reproductive toxicity , genotoxicity , rat metabolism, and mouse immunotoxicity . Since the last risk assessment, the HED HASPOC waived the requirement for a neurotoxicity battery (acute and subchronic) and a DNT study based on a WOE approach that considered (1) lack of neurotoxic effects in the available acute, subchronic, chronic, developmental, and reproduction studies; (2) the selected endpoints are considered to be protective of neurotoxic effects; (3) dietary exposure to quinclorac is low; and (4) residential and occupational MOEs are high ( HASPOC TXR 0056385 ) . The requirement of a 28 - day i nhalation t oxicity s tudy was also waived previously based on low v olatility, low acute inhalation toxicity

and large extrapolated inhalation MOE ( D376603 , 23 September 2010) . **4.2. Absorption, Distribution, Metabolism, & Elimination (ADME)**  The metabolism of quinclorac ((2,3,4 - 14 C)3,7 - dichloro - 8 - quinolinecarboxylic acid) following oral administration was studied extensively in male and female CD rats. The compound was rapidly absorbed and eliminated in the urine following administration of single oral doses of ( 14 C) quinclorac at 15 or 600 mg/kg or after dail y exposures of unlabeled compound at 15 mg/kg for 14 day s followed b y a single 15 mg/kg oral dose of labeled compound . Elimination in the urine 5 day s after dosing accounted for 91 to 98 % of the dose with only 1 to 4 % eliminated in the feces. No radioactivity was dete cted in expired air. Biliary excretion was significant (11.5 to 14.5 % of the dose) in animals receiving 600 mg/kg. However, most of this radioactivity was reabsorbed from the intestines and eliminated in the urine. Most of the radioactivity in the bile is associated with the glucuronide conjugate of quinclorac. The conjugate is apparentl y h ydrol yz ed in the intestines and reabsorbed. Almost all the radioactivity in the urine is unchanged quinclorac. Radioactive tissue residue levels 5 days after dosing were dose - dependent. Results from these and whole - body autoradiography and time - course studies indicate that relativel yQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **23** of **80** higher radioactivity

levels were detected in the adrenal glands, bone marrow, thy roid, squamous epithelium of the non - fundic stomach, and ovaries compared to the other body organs/tissues. In 7 - day time - course studies (oral gavage at 15 mg/kg/day or dietary

at about 1,000 mg/kg/day) maximum 14 C residue levels were detected 30 minutes after the final dose; thereafter, residue le vels decreased with time. Mean 14 C residues in plasma wer e also detected at 30 minutes in animals receiving single oral doses of 15, 100, or 600 m g/kg or 15 mg/kg/day for 7 day s. Elimination was biphasic with half - lives of 3 to 4 hours for the rapid phase at the low doses and a half - life of about 13 hours at 600 mg/kg. Peak plasma levels of radioactivity in animals receiving higher doses (1200 mg/kg or 600 mg/kg/day for 7 day s) were noted for 7 to 48 hours post dosing; saturation kinetics were also noted at these higher doses.

**4.2.1. Dermal Absorption**  Dermal penetration studies on quinclorac are not available. There was no dermal toxicity seen at the limit dose of 1000 mg/kg/day in a 21 - day

dermal toxicity

study in rabbits . **4.3. Toxicological Effects**  Quinclorac toxi city

in experimental animals is observed mostly at doses above 150 mg/kg/day following subchronic and chronic exposures. Subchronic toxicity includes decreased body weight gains, increased water intake, increased liver enzy mes (SGOT, SGPT) and focal chron ic interstitial nephritis (rats). Chronic toxic effects include body weight decrement, increase in kidney and liver weights, and hydropic degeneration of the kidney s (dogs). At high doses, chronic toxicity

also includes increased incidences of pancreatic acinar cell hy perplasia and adenomas (rats). Neurotoxic effects were not observed in any of the acute, subchronic and chronic studies with quinclorac. There was no increased qualitative or quantitative fetal or offspring susceptibility in the prenatal developmental or postnatal reproduction studies. Developmental toxicity in the rabbit consisted of increased resorptions, post - implantation loss, decrease d number of live fetuses, and reduced fetal body weight. These effects occurred at much higher dose s than the maternal effects of decrease d food consumption and increase d water consumption and decreased body weight gain . In the rat no developmental toxicity was observed at the highest dose tested (438 mg/kg/day) . In the 2 - generation reproduction study , parental toxicity and offspring toxicity occurred at the same dose. Parental toxicity

consisted of reduced body weight in both sexes during premating and lactation periods. Offspring toxicity consisted of decreased pup weight, developmental delay s and possible marginal effect on pup viability . No reproductive toxicity occurred at the highest dose tested ( 480 mg/kg/day) . There are no mutagenicity concerns . Quinclorac is not mutagenic in bacterial assays and does not cause unscheduled DNA damage in primary rat hepatocy

tes. There is also no evidence of a genotoxic response in whole animal test sy stems ( in vivo mouse bone marrow micronucleus assay) . Quinclorac was negative in a mammalian cell in vitro c yt ogenetic c hromosomal a berration a ssay

in Chinese h amster o vary cells (CHO) .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **24** of **80** Quinclorac was classified in 1992 by the HED Cancer Peer Review committee (CPRC) as a group D carcinogen - not classifia ble as to human carcinogenicity- based on recommendation b y the EPA Scientific Advisory Panel (TXR# 0010416 ). This classification was based on equivocal increase in the incidence of one ty pe of benign tumor (pancreatic acinar cell adenomas) in only one se x and one species of animals (male Wistar rats). Based on this classification, a quantification of cancer risk is not warranted because the chronic RfD will adequatel y account for all chronic effects, including carcinogenicity , likely to result from exposure to quinclorac. Quinclorac (technical grade material) has a low order of acute toxicity as demonstrated by Toxicity Category I II b y the oral, dermal, and inhalation routes. The chemical is a mild eye irritant, is not a skin irritant, but was positive for dermal sensitization. The complete toxicity

profile for quinclorac is provided in Appendix A. **4.4. Safety F**  **actor for Infants and Children (FQPA Safety Factor)** The FQPA Safety Factor Committee recommend ed in 1998 that the 10x factor for the protecti on of infants and children (as required b y FQPA) be removed (TXR 0012902) **.** The removal of the 10x factor is based on 1) c ompleteness of the data base ; 2) there is no indication of increased susceptibility

of rats or rabbit fetuses to in utero and/or postn atal exposure in the developmental and reproductive toxicity data; 3) unrefined (Tier 1) dietary exposure estimates are protective since they exaggerate the dietary

exposure estimates; and 4) modeling data are used for ground and surface source drinking water exposure assessments resulting in conservative upper- bound concentrations .**4.4.1. Completeness**  **o f**  **the Toxicology Database**  The toxicology

database for quinclorac is complete and the risk assessment team has concluded that the FQPA safety factor can be reduced to 1x. The following acceptable studies are available for FQPA consideration: (1) Developmental toxicity studies in rats and rabbits; and (2) Two generation reproduction study in rats. Acute and subchronic neurotoxicity studies have been waived per HASPOC (TXR# 0056385).

**4.4.2. Evidence of Neurotoxicity**  There are no acute, subchronic or chronic neurotoxicity studies on quinclorac available from the registrant or from the published literature. Neurotoxic effects were not observed in any of the acute, subchronic and chronic studies with quinclorac. Because of the lack of evidence of neurotoxic effects, HIARC (TXR# 0012717) determin ed in 1998 that no acute, subchronic, or developmental neurotoxicity studies are required for quinclorac. This was confirmed by HASPOC in 2012 ( TXR# 0056385) .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **25** of **80 4.4.3.**  **Evidence o**  **f Sensitivity/Su sceptibility in the Developing o**  **r Young Animal**  The toxicology

d atabase for quinclorac is adequate for the FQPA assessment. Developmental toxicity studies in rats and rabbits and the reproduction studies in rats provided no indication of increased qualitative or quantitative susceptibility .

**4.4.4. Residual**  **Uncertainty in the Exposure Datab**  **ase** There are no residual uncertainties with regard to dietary and residential/occupational exposure. The dietary

exposure assessments are based on tolerance level residues and 100% crop treated information. Modeled values were used fo r drinking water estimates . Occupational and residential exposure assessments are based on reasonable worst - case assumptions and will not likely underestimate potential exposure or risk. Based on these data, the quinclorac risk assessment team concluded th at no additional safety factor is needed to account for exposure considerations. **4.5. Toxicity Endpoint and Point of**  **D eparture Selections**  **4.5.1. Dose**  **- Response Assessment**  Toxicity endpoints and points of departure (PODs) for dietary and occupational exposure scenarios are summarized below. A detailed description of the studies used as a basis for the selected endpoints are presented in Appendix A. An appropriate endpoint attributable to a single exposure to assess dietary exposure for the g eneral p opulations including i nfants and c hildren was not available from the oral toxicity studies including the rat and rabbit developmental toxicity studies. An acute dietary POD of 200 mg/kg (NOAEL) for the sub - population females 13 - 49 years old was selected from a rabbit developmental toxicity study based on increased rate of resorption s and post - implantation loss, a decrease in the number of live fetuses, and reduced fetal body weight seen at 600 mg/kg/day . A UF 10 0x ( 1 0x for intraspecies variation, 10 x for interspecies extrapolation and a 1x FQPA safety factor) was applied to the dose to obtain an acute reference dose/ population adjusted dose ( aRfD/ aPAD) of 2.0 mg/kg . A chronic dietary POD of 37.5 mg/kg/day (NOAEL) was selected for the general populatio n from a carcinogenicity

study in mice based on effects on body weight . A UF 10 0x ( 1 0x for intraspecies variation, 10 x for interspecies extrapolation and a 1x FQPA factor) was applied to the dose to obtain a chronic reference dose/ population adjusted dose (cRfD/cPAD) of 0. 3 8 mg/kg/day . A POD of 70 mg/kg/day (NOAEL) for assessing i ncidental oral short - term (1 - 30 day s) as well as short - and intermediate term inhalation exposure scenarios was selected from the d evelopmental toxicity study in rabbits based on decreased maternal body weight gain and food consumption (and increased water consumption) at 200 mg/kg/day . This is s upported b y subchronic andQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **26** of **80** chronic dietary

data on mice. The LOC for MOE of 100 is applied for this exposure scenario. This inc ludes 10X for interspecies extrapolation, 10X for intraspecies variation and a 1x FQPA SF . A dermal endpoint was not selected because an appropriate endpoint was not available ( i.e. no dermal toxicity was seen at limit dose of 1000 mg/kg/day in a 21 - day

d ermal toxicity

study). In addition, there were no susceptibility concerns. Long - term inhalation exposure is not anticipated based on the current use pattern for quinclorac. Therefore, long - term PODs have not been established.

**4.5.2. Recommendation for Combining**  **Routes of Exposures for Risk Assessment**  Under FQPA, when there are potential residential exposures to the pesticide, aggregate risk assessment must consider exposures from three major sources: oral, dermal and inhalation exposures. These combined residential exposures must then be aggregated with dietary exposure (food and drinking water) to determine aggregate risk . Dermal exposures were not quantified due to a lack of a dermal toxicological endpoint. Because the inhalation and incidental oral endpoints are based on the same endpoint from the same study , the developmental rabbit, exposures from these routes may

be combined. **4.5.3. Cancer Classification and Risk Assessment Recommendation**  Quinclorac was classified in 1992 by the HED Cancer Peer Review committee (CPRC) as a group D carcinogen - not classifiable as to human carcinogenicity- based on recommendation b y the EPA Scientific Advisory Panel (TXR# 0010416 ). This classification was based on equivocal increase in the incidence of one ty pe of benign tumor (pancreatic acinar cell adenomas) in only one sex and one species of animals (male Wistar rats). Based on this classification, a quantification of cancer risk is not warranted because the chronic RfD will adequatel y account for all chronic effects, includi ng carcinogenicity , that may result from exposure to quinclorac. There was no evidence o f carcinogenicity in mice or female rats .

**4.5.4. Summary of Points of Departure and Toxicity Endpoints Used in**  **Human Risk Assessment** Toxicological doses and endpoints for dietary and non - occupational human health risk assessments for quinclorac are presented below in Table 4.5.4.1.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **27** of **80 Table 4.5.4.1.**  **Summ ary of Toxicological Doses and Endpoints for Quinclorac for Use in Dietary and Non**  **** **Occupational Hum an Health Risk Assessments.**  **Exposure/ Scenario**  **Point of**

**Departure Uncertainty/FQPA** 

**Safety Factors RfD, PAD,** 

**Level of Concern**  **for Risk Assessment**  **Study and Toxicological Effects** Ac ute Dietary (General Population, including Infants and Children) Not applicable. An endpoint for acute dietary exposure to the general population was not selected

because there was no available endpoint attributable to a single dose that was appropriate for this scenario (effects observed in the available studies are presumed to require more than one exposure).

Ac ute Dietary (Females 13 - 49 years of age) NOAEL

(developmental) = 200 mg/kg/day UF A= 10x

UF H =10x FQPA SF= 1x aRfD = 2.0

mg/kg/day aPAD = 2.0 mg/kg/day Developmental toxicity study in rabbits

(MRID# 41063525 and 41680501) Developmental toxicity LOAEL = 600 mg/kg/day based on increased early resorptions and postimplantation loss, decreased live fetuses, decreased fetal body weight. These fetal effects ar e 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 cRfD = 0.38

mg/kg/day cPAD = 0.38 mg/kg/day Carcinogenicity study in mice

( MRID # 41063523) LOAEL = 150 mg/kg/day based on decreased body weight. Incidental Oral Short Term (1 - 30 days) NOAEL= 70

mg/kg/day UF A= 10x

UF H =10x FQPA SF= 1x Residential

LOC for MOE = 100 Developmental toxicity study in rabbits.

(MRID# 41063525 and 41680501) 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 appropriate endpoint was not

available (no dermal toxicity was seen at the limit dose of 1000 mg/kg/day in a 21 - day dermal toxicity study). Inhalation Short - Term (1 - 30 days) and Intermediate Term (1 - 6 mo nths) 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.

(MRID# 41063525 and 41680501) Maternal toxicity LOAEL = 200 mg/kg/day based on decreased maternal body weight gain and food consumption , and increased water consumption. Inhalation Long - Term (>6 months) Not applicable. Long - term inhalation exposure is not anticipated under current use scenarios. Cancer (oral, dermal, inhalation) Quinclorac was classified in 1992 by the HED Cancer Peer Revie w committee (CPRC) as a group

D carcinogen - not classifiable as to human carcinogenicity - based on recommendation by the EPA Scientific Advisory Panel (TXR# 0010416). This classification was b ased on equivocal increase in the incidence of one type of benign tumor (pancreatic acinar cell adenomas) in only one sex and one species of animals (male Wistar rats). A quantification of cancer risk is not warranted because the chronic RfD will adequate ly account for all chronic effects, including carcinogenicity, that may result from exposure to quinclorac. There was no evidence of carcinogenicity in mice or female rats.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **28** of **80** Point of Departure (POD) = A data point or an estimated point that is derived fr om 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 adverse effect level. UF = uncertainty factor. UF A = extrapolation from animal to human (interspecies). UF H = potential variation in sensitivity among members of the human 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 Safety Factor. PAD = population adjusted dose (a = acute, c = chronic). RfD = reference dose. MOE = margin of exposure. LOC = level of concern. N/A = not applicable.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **29** of **80 Table 4.5.**  **4 .2 Summary of Toxicological Doses and Endpoints for**  **Quinclorac for Use in Occupational Hum**  **an Health Risk Assessments**  **Exposure/ Scenario**  **Point of**

**Departure Uncertainty** 

**Factors Level of Concern** 

**for Risk**  **Assessment Study and Toxicological Effects**  Dermal (all durations) Not applicable. A dermal endpoint was not selected because an appropriate endpoint was not

available (no dermal toxicity was seen at the limit dose of 1000 mg/kg/day in a 21 - day dermal toxicity study). Inhalation Short - Term

(1 - 30 days) and Intermediate Term (1 - 6 mo nths) 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.

(MRID# 41063525 and 41680501) Maternal toxicity LOAEL = 200 mg/kg/day based on decreased maternal body weight gain and food consumption , and increased water consumption. Cancer (oral, dermal, inhalation) Quinclorac was classified in 1992 by the HED Cancer Peer Revie w committee (CPRC) as a group

D carcinogen - not classifiable as to human carcinogenicity - based on recommendation by the EPA Scientific Advisory Panel (TXR# 0010416). This classification was b ased on equivocal increase in the incidence of one type of benign tumor (pancreatic acinar cell adenomas) in only one sex and one species of animals (male Wistar rats). A quantification of cancer risk is not warranted because the chronic RfD will adequate ly account for all chronic effects, including carcinogenicity, that may result from exposure to quinclorac. There was no evidence of carcinogenicity in mice or female rats. 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 ob served adverse effect level. LOAEL = lowest observed adverse effect level. UF = uncertainty factor. UF A = extrapolation from animal to human (interspecies). UF H = potential variation in sensitivity among members of the human 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 acc ount for the absence of key data (i.e., lack of a critical study). MOE = margin of exposure. LOC = level of concern. N/A = not ap plicable. **4.6. Incident Reports**  Quinclorac incidents were previousl y anal yz ed in 2007 ( M. Hawkins , 08/30/2007, D 343370 ). In the previous review, two incidents were identified in IDS from 1999 to 2007; a total of five quinclorac cases were identified in the PCC data base 1993 to 2005; and there were no incidents identified in National Institute of Occupational Safety and Health Sentinel Event Notification Sy stem for Occupational Risks (NI OSH SENSOR) data from 1998 to 2003 . The document concluded that " No mitigation actions are necessary for quinclorac at this time . ” Updated incident anal ys is of the Main and Aggregate Incident Data S ys tem (IDS) from January 1, 2007 , to August 14 , 2012 , shows an increase in the number of incidents since the previous incident review performed in 2007. This is most likely due to the fact that, prior to 2007, all quinclorac products used to treat residential turf could be applied only by a certified applicator . This was a se lf - imposed restriction by

the registrant. In 2007, the registrant requested this restriction be removed. Since the restriction was removed in 2007, there have been approximately 19 quinclorac products intended for use on residential turf registered that m ay be applied by

the homeowner. Obtaining additional information on current usage data for quinclorac would improve future assessments . The updated analy sis of NIOSH SENSOR from 1998 to 2008, isQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **30** of **80** not current enough to represent the more recent residential registrations but is consistent with the previous 2007 review . It should be noted the SENSOR dataset through 2009 is forthcoming (NIOSH plans to provide the updated dataset within the 2012 calendar ye ar) and will be anal yz ed for additional quinclorac cas es. Overall, onl y a moderate number of incidents have been reported involving quinclorac. The vast majority of these incidents were of low severity, although, there were a few high severity outcomes reported in the IDS database. While incident information can be an important source of feedback to the Agency, reports of adverse health effects allegedl y due to a specific pesticide exposure ( i.e. , an “incident”) are largel y s elf - reported and therefore, generally speaking, neither exposure to a pesticide o r reported s ymptom (or the connection between the two) is validated or otherwise confirmed. Typically , causation cannot be determined based on incident data. The Agency will continue to monitor the incident information and if a concern is triggere d, addi tional anal ys is will be performed (Memo, S. Recore, 9/25 /2012, D405512 ) .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **31** of **80 5.0.**  **Dietary Exposure and Risk Assessment 5.1.**  **Metabolite/Degradate Residue Profile 5.1.1.**  **Summary of Plant and Animal Metabolism Studies** The qualitative nature of quinclorac residues in plants was considered adequately 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 vari ous matrices was identified as parent compound. Based on the metabolite profiles observed in these studies, quinclorac undergoes h ydrox yl ation of the quinoline ring of the parent, followed b y conjugation with glucose and other biologically available compo unds at the hydroxylated site. Some radioactive residues are incorporated into the high molecular weight natural products. Based on the above studies, HED concluded that parent is the onl y residue of concern in plant commodities for purposes of the tolerance expression and risk assessment. However, all three metabolism studies 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 conditions. 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 anal ysis at PHI=97 day s. Field plants were treated 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. Gre ater 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 loam y sand soil with low organic matter. Treatment levels were 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 anal yz ed at various stages of maturity, including forage samples collected at twenty- five day s after the postemergence treatment, and mature stover and grain collected at the final harvest (120 DAT). **T able**  **5.1 . 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 <0.01Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **32** of **80** The radioactive residues of quinclorac found in sorghum following typical agricultural practices consist predominantly

of parent compound. A minor metabolite, the methyl ester of quinclorac, is found in all tissues, but alway s at less than 10% TRR. A lo wer percentage of the residue in sorghum fodder was found to be quinclorac, but the majority of the residue was soluble polar compounds. The current anal ytical methodology (BASF Method No. A8902) employ s a similar acetone extraction step as used in the ab ove 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 planting, 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. **T able**  **5 .2**  **. Distribution and Identification of Residues from Wheat RACs Treated at 0.446 lb ai/A Quinclorac.** 

RAC Radioactive Residues

ppm Identified Unidentified Unextracted Marc

quinclorac quinclorac methyl ester aqueous acetone soluble hydrolyzable non - hydrolyzable %TRR ppm %TRR ppm %TRR ppm %TRR ppm %TRR 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 b y which plants metabolize quinclorac is through the hydrox yl ation of the quinoline ring of the parent, followed by the conjugation of glucose and other biologically available compounds at the hydroxylated site. Ultimately , some radioacti ve residues are incorporated into the high molecular weight natural products. The petitioner, IR - 4, requests a waiver from the requirement of another metabolism study based on the following. In the studies to date it has been shown that in plants the primary path b y which quinclorac is metabolized is through hydroxylation of the quinolone ring of the parent, followed b y the conjugation of glucose and other biologicall y available compounds at the hydrox yl ated 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). In addition, 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 o n a wide variety of plant matrices (cucumber, grape, sugarbeet, andQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **33** of **80** 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 largel y on the surface of treated plants. The presence of multiple unidentified polar residues suggests that metabolism of quinox yf en does occur to some extent to form more polar soluble components with the incorporation into insolubl e material. Conclusions. While the metabolism of quinclorac is adequatel y understood with regard to the currentl y 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 quinclorac 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 measured 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 understood based upon the adequate goat and poultry

metabolism studies (MRIDs 41076104 and 41063535 , respectivel y). In both studies, quinclorac was the principal residue identified in each commodity . HED conclu ded that parent is the onl y residue of concern for risk assessment and tolerance expression for livestock. However, the enforcement method includes a methylation step and determines the methyl ester of quinclorac. In a rat metabolism study (MRID 4106353 3 ), quinclorac was the primary metabolite reported. 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 ti me.

**5.1.2. Summary of Environmental Degradation**  M. Lowit, N. Andrews, D397720, 8/9/12 ; M. Lowit, N. Andrews, D 405093 , 9/ 14/ 12 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. Laboratory data indicate that quinclorac is stable to hydrol ys is, photoly sis in sterile water, aerobic soil metabolism, and aquatic metabolism (aerobic and anaerobic). Conversely , quincl orac undergoes rapid photoly sis in non - sterile rice paddy , natural river waters, and 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 day s. Base d on available laboratory studies, two major (BH 514 - 1 and BH 514 2 - OH; >10% applied) and one minor (BH 514 - HMe - ester; <10% applied) metabolites of quinclorac were identified. The adsorption coefficients for quinclorac and its degradation products suggest that leaching could be a route of dissipation. Field studies indicate that quinclorac is moderately persistent to persistent (18 - 176 day half - lives) in terrestrialQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **34** of **80** environments. The octanol/water partition coefficient (KOW) of 0.266 also suggests that quinclorac has a low potential to bioaccumulate. A detailed assessment of the environmental fate of quinclorac can be found in the new chemical risk assessment (DP 250179+).

**5.1.3. Comparison of Metabolic Pathways**  Quinclorac was the predominant metabolite in all 3 plant metabolism studies (all in grains), and in the livestock metabolism study and the rat metabolism study . Small amounts of a methyl ester in plants was reported. The primary

path b y which plants metabolize quinclorac is through the hydrox yl ation o f the quinoline ring of the parent, followed by the conjugation of glucose and other biologically available compounds at the hydroxylated site. Ultimately , some radioactive residues are incorporated into the high molecular weight natural products. The forage, fodder, and straw reported a number of aqueous metabolites, which would be polar metabolites, such as hydrox yl ated metabolites or conjugates. The qualitative nature of quinclorac residues in livestock is understood based upon adequate goat and poultry metabolism studies (MRIDs 41076104 and 41063535 , respectively) . Q uinclorac was the principal residue identified in each commodity. In a rat metabolism study (MRID 41063533 ), quinclorac was the primary metabolite reported. Elimination was primarily in the urine (91 - 98%) with small amounts in the feces (1 - 4%) eliminated by

day 5 after dosing. **5.1.4. Residues of Concern Summary and Rationale**  Quinclorac was not reviewed b y ROCKs or its predecessor. Previous risk assessment teams determined that quinclorac wa s the residue of concern since it was the predominant metabolite. **Table 5.1.4 Summary of Metabolites and Degradates to be included in th**  **e Risk Assessment and**  **Tolerance Expression** Matrix Residues included in Risk Assessment Residues included in Tolerance Expression Plants Primary Crop Quinclorac Quinclorac

Rotational Crop Quinclorac Quinclorac Livestock Ruminant Quinclorac Quinclorac

Poultry Quinclorac Quinclorac Drinking Water Quinclorac Not Applicable **5.2. Food**  **Residue Profile** Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **35** of **80** D397719, D404569, D404912, S. Hummel, G. Otaki e , 9/6/12 Residue Analytical Methods: An adequate GC/ECD method is available for enforcing the proposed tolerances, and the field trial data were collected using an L C/MS/MS method adequate for determining quinclorac, per se. If LC/MS/MS is to be used, a method is needed for the methyl ester of quinclorac and any other metabolites found in the required metabolism study . Multiresidue Methods : Adequate data are available evaluating quinclorac through the FDA Multi - Residue Methods Test guidelines, and quinclorac is detected b y Protocol B. Quinc lorac is not detected b y the other FDA MRM protocols. Storage Stabilit

y : The available storage stability data are adequate and support the storage conditions and durations incurred in the existing field trials, for currentl y registered uses. The IR - 4 con current storage stability data for rhubarb and cranberry are adequate for residues of quinclorac, demonstrating stability for the time and conditions the samples were stored. Storage stabilty data are needed for residues of the methyl ester of quinclorac and other residues of concern found in the required metabolism study . Water, Fish, and Irrigated Crops : For existing use on rice and the proposed use on cranberry , a label restriction is needed reg arding the use of treated rice and cranberry fields for aquaculture. Alternativel y, 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 r estriction 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. Meat, Milk, Poultry, and Eggs : Adequate cattle and poultry feeding studies are available . The uses proposed in this petition do not involve livestock feeds, and will 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 diet ary burden. Conclusions. Tolerances in livestock commodities will be changed in connection with Registration Review. Residues are expected to be found in meat by products and fat but not in milk and eggs. The dietary burden for hogs and poultry is low enough that no quantifiable residues are expected in hog and poultry commodities.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **36** of **80 Crop Field Trials:**  Cranberry (for 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 WItrials (WI01 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 characteri sti c s for the MA trials. HED has concluded that there are insufficient distinguishing characteristics to classify the WIpair as separate trials; however, the trials were conducted prior to development of the guidance on field trial differentiation. Followin g two foliar broadcast applications of the 3.8 lb ai/gal SC formulation of quinclorac at 0.484 - 0.528 lb ai/A, residues of quinclorac (and per trial averages) in/on cranberry harvested at a 57 - to 62 - day

PHI were 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 con ducted in the United States during the 2009 growing season in the North American Free Trade Agreement (NAFTA) Growing Zones 5 (MI ; 1 trial) and 12 (OR; 3 trials). The two rhubarb trials in Canb y, 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 o n location (>20 miles apart) and spray

volume (>25% higher at the Hillsboro site). There are insufficient distinguishing 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 harvested at a 29 - to 33 - day

PHI were 0.05 - 0.231 (0.082 - 0.205) ppm. The method LOQ was 0.05 ppm. 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) was 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. Samples must be reanal yz ed for the methyl ester of quinclorac and any other residue of concern found in the metabolism study . IR - 4 should not e the current guidance for differentiating field trial sites. Existing Uses of Remaining Crops :Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **37** of **80** Existing uses of Qui n clorac include use on rice, wheat, soy beans, barley

(import), grass forage and hay . Field trial data are adequate to support the existing uses of quinclorac on rice, grain sorghum, barley

(imported), and pa sture and range grasses . In decline studies, 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. Processed Food and Feed There are no processed commodities in connection with the current petition. For registration review, processing studies submitted to support existing tolerances are adequate. Proc essing studies were submitted for Rice (MRID 41063543 ), Sorghum (MRID#44322213), and Wheat ( MRID#44322209 ). Residues of quinclorac concentrate in hulls and in some grain milled products. Available processing data are adequate to support the currently regi stered uses of quinclorac. Confined and Field Accumulation in Rotational Crops A dequate rotational crop studies are available to support the use of quinclorac. 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 120 and/or 270 day s after a quinclorac application to rice . (The analy

tical 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 valid ation (LLMV ). Quantifiable residues of concern are not expected at rotational crop intervals of 120 day s or longer . **5.3. Water Residue Profile**  M. Lowit, N. Andrews, D397720, 8/9/12 ; M. Lowit, N. Andrews, D 405093 , 9 / 14/12 The current assessment is performed according to current EFED guidance and up - to - date models including the Tier II surface water model (PRZM/EXAMS) for all uses of quinclorac except cranberries and rice . Screening - level Tier I modeling was used to estimate surface water concentrations for use on cranberry (provisional cranberry

model) and rice (Tier I rice model) because the current Tier II model is not parameterized for those uses. The Tier I SCI - GROW model was used to estimate groundwater concentrations f or all uses. As in past assessments, this assessment does not consider quinclorac major degradation products BH 514 - 1 and BH 514 2 - OH. Although these degradates were detected in the laboratory studies, they seem to be intermediate degradates (DP 344485), and were not found in field dissipation studies at any

significant levels. Furthermore, since quinclorac is persistent and mobile, it is expected to be the predominant residue in ground and surface waters.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **38** of **80** Surface water EDWCs (acute = **511 μg/L** and chroni c = **511 μg/L** ) resulting from use on rice supersede previousl y recommended EDWCs. The recommended groundwater EDWC has not changed ( **29 μg/L** for acute and chronic exposure). **Table 5.3a**  **. Estimated Drinking Water Concentrations (EDWCs) of Quinclorac in Su rface**  **Water Sources.**

**Use Scenario**  **Estimated Drinking Water Concentrations from** **Surface Water Sources (μg/L) 1,2,3**  **1 -**  **in -**  **10 year acute**  **1 -**  **in -**  **10 year**

**chronic 30**  **- year** 

**mean** Turf grasses (1.4 lb ai/A x 1) (0.76 lb ai/A x 2) FL turf 4 41.3 28.5 16.8

PA turf 4,5 58.3 37.8 20.0 FL turf 4 43.1 32.8 16.3 PA turf 4,5 74.1 62.0 **23.7** Sorghum (0.375 lb ai/A x 2) (0.245 lb ai/A x 3) KS sorghum (postplant) 6 26.3 10.5 6.9

KS sorghum (postplant/fall) 7 20.5 10.2 6.3 KS sorghum (preplant) 23.6 9.5 6.4 Wheat ND wheat (preplant

spring) 38.7 26.9 16.5 ND wheat (preplant winter) 46.6 28.6 19.3 Rangeland / Pasture FL turf 4 29.3 21.2 14.6 PA turf

4,5 36.6 25.3 16.0 CArangelandhayRLF_v2 4 54.0 36.9 20.5 Rights of way /Fencerow /Hedgerows 1.5 lb ai/A x 1 0.76 lb ai/A x 2 CArightofwayRLF_v2 4 24.7 14.9 8.2

CArightofwayRLF_v2 4 27.7 14.3 8.4 Grass grown for seed4,5 ORgrassseed4,5 25.4 15.8 11.0 Fallow land FL turf 4 27.1 19.6 13.7 PA turf

4,5 31.5 21.1 13.6 CArangelandhayRLF_v2 4 39.3 27.2 16.4 Grass forage /Fodder /Hay FL turf 4 26.4 18.5 14.4 PA turf

4,5 27.1 21.4 14.9 CArangelandhayRLF_v2 4 46.8 31.7 20.6 Low growing berry (except cranberry and strawberry) ORberriesOP 3.4 2.0 1.3 Rhubarb CA cole crop RLF_v2 33.8 18.0 11.4

CA lettuce 27.9 18.8 12.9 Cranberry Provisional Cranberry

Model 8 161.9 147.2 --Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **39** of **80 Use**  **Scenario Estimated Drinking Water Concentrations**  **from Surface Water Sources (μg/L)**  **1,2,3 1**  **- in**  **- 10 year**  **acute 1**  **- in**  **- 10 year** 

**chronic 30**  **- year** 

**mean** Rice Tier I Rice Model 9 **511.1 511.1**  **--** Aquatic Weeds 10 Labeled concentration 500.0 500.0 **--** 1 PCA = 1 ( www.epa.gov/oppefed1/models/water ) because this is a national drinking water assessment and quinclorac is registered for non - agricultural, non - turf uses. 2 **BOLD** indicates highest EDWC 3 EDWCs based on aerial applications are presented for uses that permit aerial and ground applications at the same application rate. 4 Highest value of twelve estimates (first application on the first day of each month) because there are no restrictions on when pesticide may be applied. 5 Although permitted, it was assumed that winter applications would be unlikely (December, January, February). 6 Two applications between preemergence and postemergence (up to 12 inches) 7 One application between preemergence and postemergence (up to 12 inches) and one application in the fal l prior to the first killing frost 8 Based on a one - year simulation; 1 in 10 year calculation is not applicable. 9 Based on a single, screening level concentration; 1 in10 year calculation is not applicable. 10 Registered as an experimental use permit.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **40** of **80 T**  **able 5.3b**  **. Estimated Drinking Water Concentrations (EDWCs) of Quinclorac in Ground Water Sources** 

**Use Application Rate**  **Estimated Drinking Water Concentrations from** **Ground Water Sources (μg/L)**  **1 Acute**  **Chronic** Turf grasses 1.4 lb ai/A x 1 27 27 0.76 lb ai/A x 2 **29 29**  Sorghum 0.375 lb ai/A x 2 and 0.245 lb ai/A x 3 14 14 Wheat 0.245 lb ai/A x 3 14 14 Rangeland / Pasture 0.75 lb ai/A x 1 14 14 Rights of way/Fencerow/Hedgerows 1.5 lb ai/A x 1 **29 29**  0.76 lb ai/A x 2 **29 29**  Grass grown for seed 0.375 lb ai/A x 2 14 14 Fallow land 0.75 lb ai/A x 1 14 14 Grass forage /Fodder /Hay 0.375 lb ai/A x 2 14 14 Low growing berry (except cranberry and strawberry) 0.25 lb ai/A x 2 10 10 Rhubarb 0.375 lb ai/A x 2 14 14 Rice 2

-- -- -- Cranberry2

-- -- -- Aquatic Weeds 2

-- -- -- 1 **BOLD** indicates highest EDWC 2 Groundwater concentrations are not estimated for aquatic uses. **5.4. Dietary Risk Assessment**  **5.4.1. Description of Residue Data Used in Dietary Assessment**  Acute and chronic aggregate dietary ( food and drinking water) exposure and risk assessments were conducted using the Dietary Exposure Evaluation Model DEEM - FCID, Version 3.16 which uses food consumption data from the U.S. Department of Agriculture’s National Health and Nutrition Examination S urvey , What We Eat in America, (NHANES/WWEIA). This dietary survey was conducted from 2003 to 2008. These anal ys es were performed to support the Section 3 request for quinclorac use s on rhubarb and low growing berry , except strawberry , subgroup 13 - 07H an d to support Registration Review for quinclorac and the dimethylamine (DMA) salt of quinclorac . All registered, pending and proposed uses of quinclorac and the DMA salt of quinclorac, as of the date of this memorandum, are included in these assessments. Tolerances have been established for quinclorac (40CFR §180.463[a]) in livestock and cereal grain commodities. HED has determined that the use of the DMA salt of quinclorac on cereal grains will not affect the established tolerances for quinclorac on rice, grain sorghum, and wheat. The residue of concern (ROC), for both tolerance enforcement and risk assessment, is the parent compound, quinclorac .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **41** of **80** The quinclorac drinking water estimates used in these dietary risk assessments w ere provided by EFED ( D P# 397720, M. Lowit/N. Andrews, 8/9/12 and DP# 405093, M. Lowit/N.Andrews, 9/14/12 ), and incorporated directly into the dietary assessments. Water residues were incorporated in DEEM - FCID via entry into the food categories “water, direct, all sources” and “water, indirect, all sources.” The estimated drinking water concentration s (EDWC s ) from existing and proposed uses of quinclorac for both acute and chronic scenarios in ground and surface water are 0.0 2 9 ppm and 0.511 ppm, respectively . Rice (labeled for a single application of 0.5 lb ai/A) was identified as the use resulting in the highest EDWCs for surface water. Because the use on rice involve s flooding ( for which the current Tier II model is not parameterized) , the surface water EDWC s were assessed using a Tier I Rice Model , Version 1.0 ( May 8, 2007). Turf grass was identified as the use resulting in the highest EDWCs for ground water. The EDWC in ground water was assessed using the Tier I Screening Concentration in Ground Water (SC I - GROW , Version 2.3 ) model. Th e s e model s, and their description s, are available at the EPA internet website via the web link, http://www.epa.gov/oppefed1/models/water/ . No surface or ground water monitoring data were available for quinclorac.

**5.4.2. Percent Crop Treated Used in Dietary Assessment**  The acute and chronic assessments are based on the assumption that 100% of all commodities with tolerances will be treated.

**5.4.3. Acute**  **Dietary Risk Assessment** The acute dietary assessment is highly conservative, and assume s 100% crop treated (%CT), along with tolerance - level residues for all agricultural commodities. Default processing factors from DEEM 7.81 were used (for dried beef and cranberry juice) in the analy ses. Tier I modeling was used to estimate drinking water concentrations. The acute (food + water) dietary risk estimate at the 95 th percentile of exposure is 1 .6 % of the acute population adjusted dose (aPAD) for females ag e 13 to 49 . This is the only population subgroup for which an acute endpoint was selected. Generally , the Agency

is concerned when risk estimates exceed 100% of the PAD . The a cute dietary risk estimate for quinclorac is below HED’s level of concern. **5.4.4. Chronic Dietary Risk Assessment**  The chronic dietary assessment is highly conservative, and assume s 100% crop treated (%CT), along with tolerance - level residues for all agricultural commodities. Default processing factors from DEEM 7.81 were used (for dried beef and cranberry juice) in the analy ses. Tier I modeling was used to estimate drinking water concentrations. The c hronic (food + water) dietary risk estimates are less than or equal to 8 .9 % of the chronic population adjusted dose (cPAD) for all population subgroups. All Infants < 1 year of age is theQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **42** of **80** most highly- exposed subgroup, utilizing 8 .9 % of the cPAD, while the general US population utilizes 3 .6 % of the cPAD. Generally , the Agency

is concerned when risk esti mates exceed 100% of the PAD . A ll chronic dietary risk estimates for quinclorac are below HED’s level of concern. **5.4.5. Cancer Dietary Risk Assessment**  Quinclorac was classified in 1992 by the HED Cancer Peer Review committee (CPRC) as a group D carcinogen - not classifiable as to human carcinogenicity- based on recommendation b y th e EPA Scientific Advisory Panel (TXR# 0010416 ). This classification was based on equivocal increase in the incidence of one ty pe of benign tumor (pancreatic acinar cell adenomas) in only one sex and one species of animals (male Wistar rats). Based on this quantifi c ation , a quantification of cancer risk is not warranted because the chronic RfD will adequatel y account for all chronic effects, including carcinogenici ty , that may result from exposure to quinclorac.

**5.4.6. Summary Table**  **Table 5.4.6. Summary of Dietary (** **Food and Drinking Water) Exposure and Risk for**  **Quinclorac Population Subgroup**  **Acute Dietary (**  **95th Percentile)**  **Chronic Dietary Cancer**  **Dietary Exposure**  **(m g/kg/day)**  **% aPAD*** **Dietary Exposure**  **(m g/kg/day)**  **% cPAD*** **Dietary Exposure**  **(m g/kg/day)**  **Risk** General U.S. Population

N/A N/A 0.013728 3.6

N/A N/A **All Infants (< 1 year old) 0.033999**  **8.9** Children 1 - 2 years old 0.023500 6.2 Children 3 - 5 years old 0.019280 5.1 Children 6 - 12 years old 0.013431 3.5 Youth 13 - 19 years old 0.010195 2.7 Adults 20 - 49 years old 0.013614 3.6 Adults 50+ years old 0.012525 3.3 **Fem ales 13**  **- 49 years old**  **0.032108 1**  **.6** 0.012893 3.4Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page **43** of **80 6.0.**  **Residential (Non**  **- Occupational) Exposure/Risk Characterization**  Ivan Nieves, D404915, D404797 , 9/18/12 Although this document addresses proposed new agricultural uses which do not involve applications by

homeowners or commercial applicators in residential settings, HED has recentl y updated the residential exposure standard operating procedures (SOPs) and body weights to be used in all human health assessments as well as the incorporation of new chemical specific toxicological information . As a result of the updated policies and parameters, all of the existing residential (non - occupational) use patterns have been reassessed in this document because these scenarios will impact the quinclorac aggregate assessment . Although, quinclorac products do not appear to be specificall y marketed towards residential handler use (i.e., homeowners); a residential handler assessment was performed to be protective of any such use. Quinclorac is currentl y registered for use on turfgrass (lawns, sod, t urf areas) including but not limited to grounds or lawns around residential and commercial establishments, multifamily

dwellings, military

and other institutions, parks, airports, roadsides, schools, picnic grounds, athletic fields, houses of worship, ceme teries, golf courses, prairie grass areas, and sod farms. Quinclorac may

also be used in and around established landscape ornamentals and ornamental gardens. The quinclorac products used in residential settings can be formulated as granular, liquid, and dry

flowable formulations. **6.1. Residential Handler Exposure**  Based on the anticipated use patterns and current labeling, typ es of equipment and techniques that can potentially

be used, residential handler exposure is expected from the existing uses. The quantitative exposure/risk assessment developed for residential handlers is based on the following scenarios : 1. Loading/Appl yi ng granules for bell y grinder , 2. Loading/Appl yi ng granules for push type rotary spreader , 3. Loading/Appl yi ng granules for a spoon; 4. Loading/Appl yi ng granules for a cup and shaker can; 5. Applying granules by hand; 6. Mixing/loading/appl yi ng liquid and dry flowable formulations via m anually - pressurized handwand, a hose - end sprayer, a backpack, and a sprinkler can; 7. Mixing/loading/appl yi ng ready- to - use formulation via a trigger sprayer, and a hose - end sprayer. For residential handlers, HED presents exposure estimates for individuals wearing shorts, short sleeved shirts, shoes plus socks. Pesticide application area assumed to be performed b y adults only , however the assessment does group 16 year olds with adults. Table 6 .1 lists the exposures and risk estimates for the residential handler scenarios . The updated exposure scenarios result in risk estimates that do not exceed HED’s level of c oncern (MOEs ≥ 100) .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 44 of 80 **Table 6 .1**  **. Quinclorac Residential (Non -**  **Occupational ) Handler Estim**  **ated Risks Form** **ulation Application** 

**Equipment/Method Application**  **Rate 1**  **Units Area** 

**Treated or Am**  **ount Handled**  **Daily Units** 

**(per day)**  **Inhalation**

**Unit Exposure**  **(m g/lb ai)**  **2 Inhalation** 

**Exposure (m**  **g/day) Inhalation** 

**Absorbed Dose**  **3 (m**  **g/kg/day) Inhalation** 

**MOE 4** 

Granule Push - ty

pe spreader 0.68 lb ai/acre 0.5 acres 0.0026 0.00088 0.000011 6,300,000 Belly grinder 0.0000172 lb ai/ft2 1200 ft2 0.039 0.0008 0.00001 7,000,000 Spoon 100 ft2 0.087 0.00015 0.0000019 37,000,000 Cup; Shaker can 0.013 0.000022 0.00000028 250,000,000 Hand dispersal 0.38 0.00065 0.0000082 8,600,000

Liquid co ncentrate Hose - end Sprayer 0.78 lb ai/acre 0.5 acres 0.022 0.0086 0.00011 650,000 Manually -pressurized handwand 0.16 lb ai/gallon 5 gallons 0.018 0.014 0.00018 390,000 Backpack 0.14 0.11 0.0014 50,000 Sprinkler can 0.0000172 lb ai/ft2 1000 ft2 0.022 0.00038 0.0000047 15,000,000 Trigger - sprayer (Ready- to - Use) 0.0172 lb ai/bottle 1 bottle 0.061 0.001 0.000013 5,300,000 Hose - end Sprayer (Ready- to - Use) 0.76 lb ai/acre 0.5 acres 0.034 0.013 0.00016 430,000 Water dispersible Granule / Dry Flowable Manually -pressurized

handwand 0.28 lb ai/gallon 5 gallons 1.1 1.5 0.019 3,600 Hose - end Sprayer 1.4 lb ai/acre 0.5 acres 0.022 0.015 0.00019 360,000 Backpack 0.28 lb ai/gallon 5 gallons 1.1 1.5 0.019 3,600 Sprinkler can 0.0000172 lb ai/ft2 1000 ft2 0.022 0.00038 0.0000047 15,000,000 1. Max application rate based on various labels containing non - occupational use sites registered for quinclorac 2. Based on Standard Operating Procedures for Residential Pesticide Exposure Assessment http://www.epa.gov/pesticides/science/EPA - OPP HED_Residential%20SOPS_Feb2012.pdf : 3. Inhalation Dose (mg/kg/day) = daily unit exposure (mg/ lb ai) * application rate (lb ai/acre) * amount handled (acres) * inhalation absorption (100%) / body weight (79.5 kg); 4. Inhalation MOE = PoD (NOAEL of 70 mg/kg/day) / Daily inhalation dose (mg/kg/day). Level of concern = 100.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 45 of 80 **6.2. Residential**  **Post -**  **Applicat ion Exposure**  There are no proposed residential uses at this time; however, there are existing registered residential use s on lawns and turf for liquid and granular formulations that have been reassessed as part of Registration Review. A summary of the exposure and risk is provided below f or use in performing an aggregate exposure assessment.

**6.2.3. Residential (Non**  **- occupational) post**  **- application inhalation**  Based on the Agency's current practices, a quantitative residential post - application inhalation exposure assessment was not performed for quinclorac at this time primarily because quinclorac’s vapor pressure ( 2.7 x 10 - 7 mm Hg @ 25.0°C) and Henry's Law Cons tant (3.72 X 10 - 2 Pa m 3 /mol - 1) indicate that the compound is relatively non - volatile under field conditions. The Agency sought expert advice and input on issues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenti cide Act Scientific Advisory Panel (SAP) in December 2009. The Agency received the SAP’s final report on March 2, 2010 (http://www.epa.gov/scipoly /SAP/meetings/2009/120109meeting.html). The Agency is in the process of evaluating the SAP report and may , a s appropriate, develop policies and procedures to identify the need for and, subsequently , the way to incorporate post - application inhalation exposure into the Agency's risk assessments. If new policies or procedures are put into place, the Agency may rev isit the need for a quantitative post - application inhalation exposure assessment for quinclorac . **6.2.4. Residential (Non**  **- Occupational) Post** **- Application Dermal and** 

**Incidental Oral** Post - application short - term dermal and incidental oral exposure is expected from q uinclorac treated turf in residential settings (i.e., lawns). Dermal exposures were not quantified due to a lack of a dermal toxicological endpoint. Incidental oral exposure risk estimates were calculated for hand - to - mouth , object - to - mouth, and soil inge stion exposure s for 1 to <2 year old children playing in the treated turf. Even though there is a granular product , an as s essment fo r episodic granular ingestion was not done since there is no applicable endpoint (i.e., no acute dietary point of departure for children) .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 46 of 80 **Table 6.2**  **. Short**  **- Term** **Oral Non -**  **dietary Ingestion Residential Post -**  **application Exposure and Risk Estimates for Quinclorac Resulting from Application to Turf**  **Lifestage Post**  **- application Exposure**  **Scenario Application**  **Rate a**  **(lb ai/A) TTR** **b**

**(ug/cm 2**  **) Oral Dose**  **c, d ,**  **e**

**(m g/kg/day)**  **Oral**

**MOEs f**  **Liquids** Child 1 < 2 year old Oral Hand - to - Mouth 1.4 0.16 0.021 3,300 Object - to - Mouth 0.00065 110,000 Soil Ingestion 4.7E - 05 1,500,000

**Granular** Child 1 < 2 year old Oral Hand - to - Mouth 0.68 0.015 0.0010 68,000 Object - to - Mouth 0.000063 1,100,000 Soil Ingestion 2.3E - 05 3,000,000 a. Application rates = maximum application rates from latest LUIS report current as of 7/19/2012 . b. Turf Transferable Residue (TTR) (Not Chemical Specific) = AR *F AR ((1 - F D ) t )* 4 . 5 x10 8 [ ug/lb ]* 2 .5 - 8 [ acre/cm2 ] c. Hand - to - Mouth Dose (mg/kg/day) = E = [HR * ( F M * SAH ) * (ET * N_Replen) * (1 - (1 - SE ) (Freq_Replen/N - Replens) )] d. Object - to - Mouth Dose (mg/kg/day) = E = [OR* CF1 * SAM O * (ET * N_Replen) * (1 - (1 - SE O ) ( Freq_Replen/N_Replen) )] e. Soil Ingestion Dose (mg/kg/day) = E = SRt * SIgR * CF1 f. Oral MOE = NOAEL (70 mg/kg/day) / Oral Dose (mg/kg/day) **6.3. Combined Residential Risk Estimates (Multiple Exposure Scenarios)**  HED combines risk values resulting from separate exposure pathway s when it is likely they can occur simultaneousl y based on the use pattern, the behavior associated with the exposed population, and the hazard associated with the points of departure. HED reviewed all residential sources of exposure to de termine which residential exposure scenarios would be appropriate to combine with dietary

exposure for an aggregate risk assessment. The onl y applicable exposure pathway s are inhalation (for adult handlers) and incidental oral (for post - application exposure to children). For children, the incidental oral scenarios (i.e., hand - to - mouth, object - to - mouth, and soil ingestion) should be considered inter - related and it is likely that they occur interspersed amongst each other across time. Combining these scena rios together would be overl yconservative because of the conservative nature of each individual assessment. **6.4. Residential Risk Estimates for Use in Aggregate Assessment**  Table 6.4 reflects the residential risk estimates that are recommended for use in the aggregate assessment for quinclorac.  The recommended residential exposure for use in the adult aggregate assessment reflects inhalation exposure from residential handlers mixing/loading/appl yi ng water - dispersable granule/dry

flowable formulations with a manually- pressurized handwand and/or backpack equipment.  The recommended residential exposure for use in the children 1<2 ye ars old aggregate assessment reflects hand - to - mouth exposures from post - application exposure to treated turf.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 47 of 80 **Table 6.4.**  **Residential Risk Estimates for**  **Use in the Quinclorac Aggregate Assessment Lifestage / Exposure Scenario**  **Dose MOE**  Adults

– Residential Handler M/L/A, Water - dispersible Granule/Dry Flowable , Manually Pressurized Handwand and/or Backpack 0.019 3,600 Children 1 < 2 Years Old - Turf (Liquids) , Hand - to - Mouth 0.021 3,300 **6.5. Residential Bystander**  **Post -**  **application Inhalation Exposure**  Based on the Agency's current practices, a quantitative post - application inhalation exposure assessment was not performed for quinclorac at this time primarily because of the low acute inhalation toxicity

(Toxicity Category III and IV), low vapor pressure 2.7 x 10 - 7 mm Hg @ 25.0°C , and the low proposed use rate s . However, volatilization of pesticides may be a source of post - application inhalation exposure to individuals nearb y pesticide applications. The Agency sought expert advice and input on issues rel ated to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009, and received the SAP’s final report on March 2, 2010 1 . The Agency is in the process of evaluating the SAP report and may , as appropriate, develop policies and procedures to identify the need for and, subsequently , the way to incorporate post - application inhalation exposure into the Agency's risk assessments. I f new policies or procedures are developed, the Ag ency may revisit the need for a quantitative post - application inhalation exposure assessment for quinclorac. **6.6. Spray Drift**  Spray drift is alway s a potential source of exposure to residents nearby to spraying operations. This is particularly

the case with aerial application (a method proposed to be employed for quinclorac ), but, to a lesser extent, could also be a potential source of exposure from the ground applic ation method also employed for quinclorac. The Agency has been working with the Spray Drift Task Force, EPA Regional Offices and State L ead Agencies for pesticide regulation and other parties to develop the best spray drift management practices. On a chemical by chemical basis, the Agency

is now requiring interim mitigation measures for aerial a pplications that must be placed on product labels/labeling. The Agency has completed its evaluation of the new database submitted b y the Spray Drift Task Force, a membership of U.S. pesticide registrants, and is developing a policy on how to appropriately appl y the data and the AgDRIFT computer model to its risk assessments for pesticides applied by air, orchard airblast and ground hydraulic methods. After the policy is in place, the Agency may impose further refinements in spray drift management practice s to reduce off - target drift with specific products with significant risks associated with drift. Although a quantitative residential post - application inhalation exposure assessment was not performed as a result of pesticide drift from neighboring treated agricultural fields, an inhalation exposure assessment was performed for flaggers. This exposure scenario is representative of a

1 Available: http://www.epa.gov/scipoly/SAP/meetings/2009/120109meeting.htmlQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 4 8 of 80 worse case inhalation (drift) exposure and may be considered protective of most outdoor agricultural and commercial post - appl ication inhalation exposure scenarios. **7.0. Aggregate Exposure/Risk Characterization**  In accordance with the FQPA, HED must consider and aggregate (add) pesticide exposures and risks from three major sources: food, drinking water, and residential exposures. In an aggregate assessment, exposures from relevant sources are added together and compared to quantitative estimates of hazard (e.g., a NOAEL or PAD), or the risks themselves can be aggregated. When aggregating exposures and risks from variou s sources, HED considers both the route and duration of exposure. **7.1. Acute Aggregate Risk**  In examining acute aggregate risk, HED has assumed that the only pathway of exposure relevant to the acute time frame is dietary exposure. Therefore, the acute aggreg ate risk is comprised on exposures to quinclorac residues in food and drinking water and is equivalent to the acute dietary risk estimates summarized in Table 5.4.6 in Section 5.4.3. The acute dietary risk estimates are well below HED’s level of concern fo r Females 13 - 49 years old. **7.2. Short**  **- Term Aggregate Risk**  In examining short - term aggregate risk, HED reviewed all residential sources of exposure to determine which residential exposure scenarios would be appropriate to combine with dietary exposure for an aggregate risk assessment. The only applicable exposure pathway s are inhalation (for adult handlers) and incidental oral (for post - application exposure to children). For children, the incidental oral scenarios (i.e., hand - to - mouth, object - to - mouth, and s oil ingestion) should be considered inter - related and it is likely that they occur interspersed amongst each other across time. Combining these scenarios together would be overl y- conservative because of the conservative nature of each individual assessment. The recommended residential exposure for use in the adult aggregate assessment reflects inhalation exposure from residential handlers mixing/loading/appl yi ng water - dispersable granule/dry flowable formulations with a manuallypressurized handwand and/or backpack equipment. The recommended residential exposure for use in the children 1<2 years old aggregate assessment reflects hand - to - mouth exposures from post - application exposure to treated turf.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 49 of 80 The Aggregate MOE s are above the LOC of 100 and are not of concern (Table 7.2). **Table 7.2 Short -**  **Term Aggregate Risk Calculations Population**  **Short -**  **T erm Scenario** 

**NOAEL mg/kg/day**  **LOC 1**  **Max**

**Allowable Exposure**  **2 mg/kg/day**  **Average**

**Food and Water**  **Exposure mg/kg/day**  **Residential**

**Exposure mg/kg/day**  **3 Tota**  **l**

**Exposure mg/kg/day**  **4 Aggregate** 

**MOE (food, water, and**  **residential) 5**  Adults

– Residential Handler M/L/A, Water - dispersible Granule/Dry Flowable , Manually Pressurized Handwand and/or Backpack 1 70 100 0.70 0.013728 0.019 0.032728 2100

Child 1< 2 years old

– Turf (Liquids) Hand - to Mouth2 70 100 0.70 0.023500 0.021 0.044500 1600 1 The LOC of 100 include s the standard inter - (10x) and intra - (10x) species uncertainty factors totaling 100, as well as an FQPA SF of 1x .) 2 Maximum Allowable Exposure (mg/kg/day) = NOAEL/LOC 3 Residential Exposure = [Oral exposure + Inhalation Exposure]. ( Source: Table 6.4 , S ection 6 . 4 ). 4 Total Exposure = Avg Food & Water Exposure + Residential Exposure) 5 Aggregate MOE = [NOAEL / (Avg Food & Water Exposure + Residential Exposure)] **7.3. Intermediate**  **- Term Aggregate Risk**  Intermediate - term aggregate exposure takes into account intermediate - term residential exposure plus chronic exposure to food and water (considered to be a background expo sure level). An intermediate - term adverse effect was identified , however**,** quinclorac is not registered for any use patterns that would result in intermediate - term residential exposure; therefore, an intermediate term aggregate risk assessment was not perfo rmed nor required. **7.4. Chronic Aggregate Risk**  In examining chronic aggregate risk, HED has assumed that the only pathway of exposure relevant to the chronic time frame is dietary exposure. Therefore, the chronic aggregate risk is comprised of exposures to quinclorac residues in food and drinking water and is equivalent to the c hronic dietary

risk estimates summarized in Table 5.4.6 in Section 5.4. 4 . The chronic risk estimates are below HED’s level of concern for all population subgroups.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 50 of 80 **7.5. Cancer Aggregate Risk**  HED has concluded that assessments using a non - linear approach (e.g. a chronic RfD - based approach) will adequately account for all chronic toxicity, including carcinogenicity that could result from exposure to quinclorac. Chronic aggregate risk estimates are below HED’s level of concern, therefore, cancer risk is also below HED’s level of concern. **7.6. Cumulative Exposure/Risk Characterization**  Unlike other pesticides for which EPA h as followed a cumulative risk approach based on a common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as to quinclorac and any

other substances and quinclorac does not appear to produce a toxic metabolite produced b y other substances. For the purposes of this tolerance action, therefore, EPA has not assumed that quinclorac has a common mechanism of toxicity with other substances. For information regarding EPA’s efforts to determine which chemicals have a common mechanism of toxicity and to evaluate the cumulative effects of such chemicals, see the policy statements released by

EPA’s Office of Pesticide Programs concerning common mechanism determinations and procedures for cumulating effects from substances found to have a co mmon mechanism on EPA’s website at http://www.epa.gov/pesticides/cumulative/. **8.0. Occupational Exposure/Risk Characterization**  There are registered agricultural uses associated with quinclorac, and the proposed new uses (i.e., rhubarb and low growing berries in subgroup 13 - 07H, except strawberry) are agricultural uses as well ; therefore, there is the potential for occupational handler and post - application exposure. However, since no dermal endpoints were selected, onl y inhalation exposure estimated risks were able to be quantified. **8.1. Short**  **- /Intermediate**  **- /Long**  **- Term/Cancer (if needed) Handler Risk**  Table 8 .1.1 presents the short - term inhalation risk estimate s for the quinclorac proposed new uses . Table 8 .1.2 presents occupational handler risk estimates associated with already registered uses. Since the short - and intermediate - term endpoints and PODs are the same for each route of exposure, only short - term exposure s w ere estimated , and are considered protective of intermediate - term exposure and risk . Oc cupational handler scenarios resulted in estimated MOEs greater than the levels of concern (inhalation L OC = 10 0) at baseline. The Agency

has evaluated scenarios that may be limited in nature such as flagging during aerial applications because engineering controls (i.e., Global Positioning Satellite technology) are now predominantly

used as indicated by

the 1998 National Agricultural Aviation Association (NAAA) survey

of their membership. Itappears, however, flaggers are still used in approximately

10 to 15 percent of aerial application operations. In cases like these, the Agency strongl y encourages the use of the engineering control system but will continue to evaluate risks for flagger s and any

other population where a clear exposure pathway exists until the potential for exposure is eliminated. The Agency is aware that NAAA is conducting another survey on exposure issues and will consider those results as are timel y and appropriate.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 51 of 80 HED has no data to assess exposure for pilots using open cockpits. The only data available are representing exposure for pilots in enclosed cockpits. Therefore, pilot exposure and risk estimates are determined assuming use of engineering control (enclose d cockpits) and baseline attire ( i.e., long - sleeve shirt, long pants, shoes, and socks); pilots are not required to wear protective gloves. With this level of protection, there are no risk estimates of concern for aerial applicators .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 52 of 80 **Table 8**  **.1.1 . Quinclorac Occupational Handler Risk Esti**  **mat es For Proposed New Uses**  **Site Exposure Scenario**  **Application Rate 1**  **Am ount Handled**  **/ Area Treated 2**  **Inhalation Unit**  **Exposures 3**  **(ug/lb ai) Inhalation**  **Dose 4** 

**(m g/k** **g -**  **day) Inhalation** 

**MOE 5**  **Worker Activity**  **Formulation Application**  **Equipment Valu** 

**e Units**  **Value Units**  **No -**  **R**

Low growing berries, except strawberries, subgroup 13 - 07H M/L DF/WDG Aerial; Chemigation 0.25 lb ai/acre 350 acres 8.96 0.0098 7,100 Groundboom 80 0.0022 31,000 Applicato r Spray

(all starting formulations) Aerial 0.25 lb ai/acre 350 acres 0.068 (Engineering Controls) 0.000074

(Engineering Controls) 940,000

(Engineering Controls) Groundboom 80 0.34 0.000085 820,000 M/L/A DF/WDG Mechanicallypressurized Handgun 0.025 lb ai/gallon 1000 gallons 3.9 0.0012 57,000 Flagger Spray

(all starting formulations) Aerial 0.25 lb ai/acre 350 acres 0.35 0.00038 180,000

Rhubarb M/L DF/WDG Aerial; Chemigation 0.37 lb ai/acre 350 acres 8.96 0.015 4,800

M/L Groundboom 80 0.0033 21,000 Applicato r Spray

(all starting formulations) Aerial 0.37 lb ai/acre 350 acres 0.068 (Engineering Controls) 0.00011

(Engineering Controls) 640,000

(Engineering Controls) Groundboom 80 acres 0.34 0.00013 560,000 M/L/A DF/WDG Mechanicallypressurized Handgun 0.037 lb ai/gallon 1000 gallons 3.9 0.0018 39,000 Flagger Spray

(all starting formulations) Aerial 0.37 lb ai/acre 350 acres 0.35 0.00057 120,000 1 Based on the proposed crops listed on the registered label ( EPA Reg. No. 42750 - 169 ) ; 2 Exposure Scien ce Advisory Council Policy #9.1 ; 3 Based on “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table” (March, 2012); 4 Inhalation Dose = Dermal Unit Exposure (ug/lb ai) x Conversion Factor (0.001 mg/ug) x Application Rate (lb ai/A) x Ar ea Treated or Amount Handled (A/day or gal/day)/BW (kg); 5 Inhalation MOE = I

nhalation NOAEL ( 70 mg/kg/day)/ I nhalation Dose (mg/kg/day) ; LOC = 100 .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 53 of 80 **Table 8**  **.1.2 . Summary of Quinclorac Registered Uses**  **Site Exposure Scenario**  **Application Rate 1**  **Am ount Handled**  **/ Area Treated 2**  **Inhalation Unit**  **Exposures 3**  **(ug/lb ai) Inhalation** 

**Dose 4**  **(m g/k**  **g -**  **day) Inhalation** 

**MOE 5**  **Work er**  **Activity Form** **ulation Application**  **Equipment Value**  **Units Value**  **Units No**  **- R** 

Rice M/L DF/ WDG Aerial

0.5 lb ai/acre 1200

acres 8.96 0.068 1,000 Gr oundboom 200 0.011 6,200

WSP Aerial 1200 0.068 (Engineering Controls) 0.00051

(Engineering Controls) 140,000

(Engineering Controls) Gr oundboom 200 0.24 (Engineering Controls) 0.00030

(Engineering Controls) 230,000

(Engineering Controls) L/ SC/EC Aerial 0.47 1200 0.219 0.0016 45,000

Gr oundboom 200 0.00026 270,000

Applicator Spray

(all starting formulations) Aerial 0.5 lb ai/acre 1200

acres 0.068 (Engineering Controls) 0.00051

(Engineering Controls) 140,000

(Engineering Controls) Gr oundboom 200 0.34 0.00043 160,000 Aerial 0.47 1200 0.068 (Engineering Controls) 0.00048

(Engineering Controls) 150,000

(Engineering Controls) Gr oundboom 200 0.34 0.0004 180,000 Flagger Spray

(all starting formulations) Aerial 0.5 lb ai/acre 350 acres 0.35 0.00077 91,000 0.47 0.00072 97,000 Sorghum and Wheat M/L DF/ WDG Aerial 0.375 lb ai/acre 1200 acres 8.96 0.050 1,400 Gr oundboom 200 8.96 0.0084 8,300 L/ SC/EC Aerial 0.35 1200 0.219 0.0012 61,000

Gr oundboom 200 0.219 0.00019 370,000 Applicator Spray

(all starting formulations) Aerial 0.375 lb ai/acre 1200 acres 0.068 (Engineering Controls) 0.00038

(Engineering Controls) 180,000

(Engineering Controls)Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 54 of 80 **Table 8**  **.1.2 . Summary of Quinclorac Registered Uses**  **Site Exposure Scenario**  **Application Rate 1**  **Am ount Handled**  **/ Area Treated 2**  **Inhalation Unit**  **Exposures 3**  **(ug/lb ai) Inhalation** 

**Dose 4**  **(m g/k**  **g -**  **day) Inhalation** 

**MOE 5**  **Work er**  **Activity Form** **ulation Application**  **Equipment Value**  **Units Value**  **Units No**  **- R**  Gr oundboom 200 0.34 0.00032 220,000 Aerial 0.35 1200 0.068 (Engineering Controls) 0.00036

(Engineering Controls) 200,000

(Engineering Controls) Gr oundboom 200 0.34 0.00030 230,000 Flagger Spray

(all starting formulations) Aerial 0.375 lb ai/acre 350 acres 0.35 0.00057 120,000 Aerial 0.35 0.00054 130,000

Agricultural fallow/idleland/conservation reserves; Nonagricultural uncultivated areas/soils; Grass forage/fodder/hay; Grasses grown for seed; Pastures and Rangelands M/L DF/ WDG Aerial 0.75 lb ai/acre 1200 acres 8.96 0.10 690 Chemigation 350 0.029 2,400 Gr oundboom 200 0.017 4,200 L/ SC/EC Aerial 0.73 lb ai/acre 1200 acres 0.219 0.0024 29,000 Chemigation 350 0.00070 100,000 Gr oundboom 200 0.00040 180,000 Applicator Spray

(all starting formulations) Aerial 0.75 lb ai/acre 1200 acres 0.068 (Engineering Controls) 0.00077

(Engineering Controls) 92,000

(Engineering Controls) Gr oundboom 200 0.34 0.00064 110,000 Flagger Spray

(all starting formulations) Aerial 0.75 lb ai/acre 350 acres 0.35 0.0012 61,000

Agricultural and nonagricultural rights of way/fencerows/hedgerows; Agricultural uncultivated areas; Utility poles/rights of way M/L DF/ WDG Mechanicallypressurized Handgun 0.15 lb ai/gallon 1000 gallons 8.96 0.017 4,200 Applicator Spray

(all starting formulations) Mechanicallypressurized Handgun 0.15 lb ai/gallon 1000 gallons 3.9 0.0073 9,600 0.296 0.014 4,900 L/A G Rotary spreader 0.68 lb ai/acre 5 acres 10 0.00043 160,000 M/L /A DF/ WDG Backpack 0.15 lb 40 gallons 2.58 0.00019 360,000Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 55 of 80 **Table 8**  **.1.2 . Summary of Quinclorac Registered Uses**  **Site Exposure Scenario**  **Application Rate 1**  **Am ount Handled**  **/ Area Treated 2**  **Inhalation Unit**  **Exposures 3**  **(ug/lb ai) Inhalation** 

**Dose 4**  **(m g/k**  **g -**  **day) Inhalation** 

**MOE 5**  **Work er**  **Activity Form** **ulation Application**  **Equipment Value**  **Units Value**  **Units No**  **- R**  L/ SC/EC 0.296 ai/gallon 0.00038 180,000

Airports/landing fields M/L /A DF/ WDG;

L/ SC/EC Backpack 0.15 lb ai/gallon 40 gallons 2.58 0.00019 360,000 Manuallypressurized Handwand 30 0.0023 31,000 Mechanicallypressurized Handgun 0.75 lb ai/acre 5 acres 42 0.0020 35,000

Commercial/industrial lawns; Recreation area and residential lawns; Ornamental lawns and turf L/A G Belly grinder 0.68 lb ai/acre 1 acres 62 0.00053 130,000 Rotary spreader 5 10 0.00043 160,000 Applicator RTU (L) Trigger- spray bottle 0.0172 lb ai/bottle 5 bottles 61.2 0.000066 1,100,000

M/L /A DF/ WDG Backpack 0.28 lb ai/gallon 40 gallons 2.58 0.00036 190,000 Manuallypressurized Handwand 30 0.0042 17,000 Backpack 0.15 lb ai/gallon 40 gallons 2.58 0.00019 360,000 Manuallypressurized Handwand 30 0.0023 31,000 Mechanicallypressurized Handgun 1.4 lb ai/acre 5 acres 42 0.0037 19,000 Mechanicallypressurized Handgun 0.75 0.0020 35,000

L/ SC/EC Backpack 0.16 lb ai/gallon 40 gallons 2.58 0.00021 340,000 Manuallypressurized Handwand 30 0.0024 29,000 Mechanicallypressurized Handgun 0.78 lb ai/acre 5 acres 1.9 0.000093 760,000 Ornamenta l lawns and turf M/L DF/ WDG Aerial; 1.4 lb 350 acres 8.96 0.055 1,300Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 56 of 80 **Table 8**  **.1.2 . Summary of Quinclorac Registered Uses**  **Site Exposure Scenario**  **Application Rate 1**  **Am ount Handled**  **/ Area Treated 2**  **Inhalation Unit**  **Exposures 3**  **(ug/lb ai) Inhalation** 

**Dose 4**  **(m g/k**  **g -**  **day) Inhalation** 

**MOE 5**  **Work er**  **Activity Form** **ulation Application**  **Equipment Value**  **Units Value**  **Units No**  **- R**  Chemigation ai/acre Gr oundboom 80 0.013 5,600 L/ SC/EC Aerial;

Chemigation 0.78 350 0.219 0.00075 94,000 Gr oundboom 80 0.00017 410,000 Applicator Spray

(all starting formulations) Aerial 1.4 lb ai/acre 350 acres 0.068 (Engineering Controls) 0.00042

(Engineering Controls) 170,000

(Engineering Controls) Gr oundboom 80 0.34 0.00048 150,000 RTU (L) Trigger- spray

bottle 0.0172 lb ai/bottle 5 bottles 61.2 0.000066 1,100,000 Flagger Spray

(all starting formulations) Aerial 1.4 lb ai/acre 350 acres 0.35 0.0022 33,000

Golf course turf M/L DF/ WDG Gr oundboom 1.4 lb ai/acre 40 acres 8.96 0.0063 11,000 G Tractor- drawn

Spreader 0.68 1.7 0.00058 120,000 L/ SC/EC Gr oundboom 0.78 0.219 0.000085 820,000 L/A G Rotary spreader 0.68 lb ai/acre 5 acres 10 0.00043 160,000 Applicator G Tractor- drawn Spreader 0.68 lb ai/acre 40 acres 1.2 0.00041 170,000 Sp ray (all starting formulations) Gr oundboom 0.78 0.34 0.00013 530,000

M/L /A DF/ WDG Mechanicallypressurized Handgun 1.4 lb ai/acre 5 acres 42 0.0037 19,000 L/ SC/EC 0.78 1.9 0.000093 760,000 1 Based on latest LUIS report current as of 7/19/2012; 2 Exposure Scien ce Advisory Council Policy #9.1; 3 Based on “Occupational Pesticide Handler Unit Exposure Surrogate Reference Table” (March, 2012); 4 Inhalation Dose = Dermal Unit Exposure (ug/lb ai) x Conversion Factor (0.001 mg/ug) x Application Rate (lb ai/A) x Ar ea Treated or Amount Handled (A/day or gal/day)/BW (kg); 5 Inhalation MOE = I

nhalation NOAEL ( 70 mg/kg/day)/ I nhalation Dose (mg/kg/day) ; LOC = 100 .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 57 of 80 **8.2. Short**  **- /Intermediate**  **- /Long**  **- Term/Cancer (if needed) Post** **- Application Risk**  HED uses the term post - application to describe exposures that occur when individuals are present in an environment that has been previously treated with a pesticide (also referred to as re entry exposure). Such exposures may occur when workers enter previously treated areas to perform job functions, including activities related to crop production, such as scouting for pests or harvesting. Post - application exposure levels vary over time and depend on such things as the ty pe of activity , the nature of the crop or target that was treated, the ty pe of pesticide application, and the chemical’s degradation properties. In addition, the timing of pesticide applications, relative to harvest activities, can greatl y reduce the potential for post - application exposure.

**8.2.1. Dermal**  **Post -**  **application Risk**  Quinclorac proposed new uses, as well as already r egistered, include agricultural sites including rice, sorghum, wheat, rhubarb and low growing berries (subgroup 13 - 07H), except strawberries. Since no toxicological dermal endpoint was selected; no dermal occupational risk estimate was quantified, and therefore no risks of concerns were identified. It is the policy

of HED to use the best available data to assess post - application exposure. Sources of generic post - application data, used as surrogate data in the absence of chemical specific data, are derived from Agricultural Reentry Task Force (ARTF) exposure monitoring studies, and, as proprietary data, are subject to the data protection provisions of FIFRA. The standard values recommended for use in predicting post - application exposure that are used in this assessment, known as “transf er coefficients”, are presented in the “Science Advisory Council for Exposure (ExpoSAC) Policy 3” http://www.epa.gov/pesticides/science/exposac_policy3.pdf)), which, along with additional information about the ARTF data, can be found at http://www.epa.gov/pesticides/science/post app - exposure - data.html .

**8.2.2. Inhalation**  **Post -**  **application Risk**  Based on the Agency's current practices, a quantitative post - application inhalation exposure assessment was not performed for quinclorac at this time primarily because of its vapor pressure (2.7 x 10 - 7 mm Hg @ 25.0°C), and the proposed use rates. However, there are multiple potential sources of post - application inhalation exposure to individuals performing post - application activities in previously

treated areas. These potential sources include volatilization of pesticides and re - suspension of dusts and/or particulates that contain pesticides. The Agency sought expert advice and input on issues related to volatilization of pesticides from its Federal Insecticide, Fungicide, and Rodenticide Act Scientific Advisory Panel (SAP) in December 2009, and received the SAP’s final report on March 2, 2010 (http://www.epa.gov/scipoly /SAP/meetings/2009/120109 meeting.html). The Agency is in the process of evaluating the SAP report as well as available post - application inhalation exposure data generated b y the Agricultural Reentry Task Force and may , as appropriate, develop policies and procedures, to identify the need for and, subsequently , the way to incorporate occupational post - application inhalation exposure into the Agency's risk assessments. If new policies orQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 58 of 80 procedures are put into place, the Agency may revisit the need for a quantitative occupational post - application inhalation exposure assessment for quinclorac. Although a quantitative post - application inhalation exposure assessment was not performed, an inhalation exposure assessment was performed for occupational handlers. Handler exposure resulti ng from application of pesticides outdoors is likely to result in higher exposure than post application exposure. Therefore, it is expected that these handler inhalation exposure estimates would be protective of most occupational post - application inhalati on exposure scenarios. **9.0. References**  Cropp - Kholligian , B. 9 /24 /20 12. Quinclorac and the Dimethylamine (DMA) Salt of Quinclorac . Acute and Chronic Aggregate Dietary (Food and Drinking Water) Exposure and Risk Assessments for the Section 3 Registration Action on Rhubarb and Low Growing Berry except Strawberry , Subgroup 13 - 07H and the Registration Review Action. D404795 and D404914 Y. Donovan et al , 8/5/20 0 9 . PP# 8F7442. Human Health Risk Assessment for Quinclorac New Use on Pasture/Rangeland. D359759 . Drew, W. and Dow, M. 6/2/2009. Quinclorac. Human Health Risk Assessment for the Proposed Food/Feed Use of the Herbicide (Associated with Section 18 Registration) on Cranberries in Massachusetts. Greear, W. and Rinde, E. 8/26/1992. Second Carcinogenicity Peer Review of Quinclorac. TXR No. 0010416. Hummel, S. and Otakie, G. 9/6/20 12. Draft. Quinclorac on Rhubarb and Low Growing Berries (except Strawberry). Summary of Anal ytical Chemistry

and Residue Data. Residue Chemistry Considerations for Registration Review. D397719, 404569, 404912 Lowit, M. and Andrews, M. 8/9/20 12. Quinclorac: Drinking Water Assessment to Support Proposed New Use on Rhubarb and Low Growing Berries Except Strawberry (subgroup 13 - 07 H). D397720. Lowit, M. and Andrews, M. 9/14/2012. Quinclorac: Registration Review Drinking Water Assessment. D405093. Nieves, I. 9/18/20 12. Quinclorac: Occupational and Residential Exposure/Risk Assessment for Registration Review and for Proposed Use s on Rhubarb and Cranberry (and other Low Growing Berries in Subgroup 13 - 07H, except strawberry) . D404915, D404797 O’Rourke, K. 9/23/2010. Quinclorac. Response to BASF Corporation’s Request to Waive the Requirement of a 28 - Day Inhalation Toxicity Study for Quinclorac. D376603. TXR No. 0055511. Recore, S. 9/25 /12. Quinclorac: Updated Tier 1 Review of Human Incidents. D405512.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 59 of 80 Shah, PV and Rowland, J. 8/4/1998. Quinclorac

– Report of the Hazard Identification Assessment Review Committee. HED Doc. No. 012717. Tarplee, B. 10/14/1998. Quinclorac

– Report of the FQPA Safety Factor Committee. TXR No. 0012902. V an Alstine, J. 9/2012. Quinclorac: Summary of Hazard and Science Policy Council (HASPOC) Meeting of June 21, 2012: Recommendations on the need for a neurotoxicity Battery Study and a DNT study. TXR #: 0056385Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 60 of 80 **A ppendix**  **A .**  **Toxicology Profile and Executive Summaries A.1**  **Toxicology Data Requirem ents**  The requirements (40 CFR 158.340) for [Type of Use (e.g., food vs. non food)] for [CHEMICAL NAME] are in Table 1. Use of the new guideline numbers does not imply that the new (1998) guideline protocols were used. **Test Technical**  **Required Satisfied**  870.1100 Acute Oral Toxicity ................................ ....................... 870.1200 Acute Dermal Toxicity ................................ .................. 870.1300 Acute Inhalation Toxicity ................................ .............. 870.2400 Primary Eye Irritation ................................ .................... 870.2500 Primary Dermal Irritation ................................ .............. 870.2600 Dermal Sensitization ................................ ...................... yes yes yes yes yes yes yes

yes yes yes yes yes 870.3100 Oral Subchronic (rodent) ................................ ............... 870.3150 Oral Subchronic (nonrodent) ................................ ......... 870.3200 21 - Day

Dermal ................................ .............................. 870.3250 90 - Day

Dermal ................................ .............................. 870.3465 21 - /90 - Day

Inhalation ................................ .................... yes yes yes no no 2 yes

yes 1 yes

-

**-** 870.3700a Developmental Toxicity (rodent) ................................ ... 870.3700b Developmental Toxicity (nonrodent) ............................. 870.3800 Reproduction ................................ ................................ . yes yes yes yes

yes yes 870.4100a Chronic Toxicity (rodent) ................................ .............. 870.4100b Chronic Toxicity (nonrodent) ................................ ........ 870.4200a Oncogenicity (rat) ................................ .......................... 870.4200b Oncogenicity (mouse) ................................ .................... 870.4300 Chronic/Oncogenicity ................................ .................... yes yes yes yes yes yes

yes yes yes yes 870.5100 Mutagenicity

—Gene Mutation - bacterial ..................... 870.5300 Mutagenicity

—Gene Mutation - mammalian ................ 870.5375 Mutagenicity

— Structural Chromosomal Aberrations ... 870.5900 Mutagenicity

—Other Genotoxic Effects ....................... yes yes yes yes yes

yes yes yes 870.6100a Acute Delayed Neurotox. (hen) ................................ ..... 870.6100b 90 - Day

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

Neuro. Screening Battery (rat) .......................... 870.6300 Develop. Neuro ................................ .............................. no no no 3 no 3 no 3 -

-

-

-

- 870.7485 General Metabolism ................................ ...................... 870.7600 Dermal Penetration ................................ ........................ 870.7800 Immunotoxicity ................................ ............................. yes

- yes yes

- yes 1 The data requirement for a dog 90 - day subchronic oral toxicity is satisfied by the dog 1 - year chronic oral study. 2 wa ived ( D376603 , TXR 0055511 ) 3 wa ived ( HASPOC , TXR 0056385 )Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 61 of 80 **A.2 Toxicity Profile**  **s Table A.2.1**  **Acute Toxicity Profile –**  **Quinclorac** Guideline No. Study T ype MRID(s) Results Toxicity Category 870.1100 Ac ute oral - rat 41063505 (1989) LD 50 >2610 mg/kg III 870.1100 Ac ute oral - rat 41063506 (1983) LD 50 (male) = 3060 mg/kg

LD 50 (female) = 2190 mg/kg LD 50 (com

bined) = 2680 mg/kg III

870.1100 Ac ute oral - mo use 41063507 (1986) LD 50 >5000 mg/kg IV 870.1200 Ac ute dermal - rat 41063509 (1983) LD 50 > 2000 mg/kg III 870.1300 Ac ute inhalation - rat 41063510 (1985) LC 50 > 5.2 mg/L

(4 hr exposure) III 870.2400 Ac ute eye irritation

–

rabbit 41063511 (1983) Mild irritant reversible by

day 8 III 870.2500 Ac ute dermal irritation

–

rabbit 41063512 (1983) Not an irritant III 870.2600 Skin sensitization

–

guinea pig 40573301 (1986) Dermal sensitizer n/aQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 62 of 80 **Table A.2.2 Subchronic, Chronic and**  **Other Toxicity Profile –**  **Quinclorac Guideline**  **No. Study Type**  **MRID No. (year)/ Classification /Doses**  **Results** 870.3100 90 - Day

oral toxicity (Wistar rat) 41063516 (1986)

**Unacceptable/non**   ** guideline** based on lack of analyses of diet concentration, homogeneity, stability. 0, 1000, 4000 or 12,000 ppm in diet M: 0, 76.8, 302, 930 mg/kg/day F: 0, 86.7, 358, 1035 mg/kg/day NOAEL = 302 mg/kg/day (males) and 358 mg/kg/day (females) LOAEL = 930 mg/kg/day (males) and 1035 mg/kg/day (females) based on decreased body weight gain, food consumption and increased water intake in males and females; increased SGOT, SGPT and focal chronic interstitial nephritis in males.

870.3100 90 - Day

oral toxicity (B6C3F1/Crl Br mo use) 41063519 (1988)

**Acceptable/guideline** when considered together with 41063519 0 or 500 ppm in diet 0 or 75 mg/kg/day NOAEL = 75 mg/kg/day (HDT) LOAEL was not established in this study (> 75 mg/kg/day)

870.3100 90 - Day

oral toxicity (B6C3F1/Crl Br mo use) 41063518 (1986)

Acceptable/guideline when considered together with 41063518 0, 4000, 8000 or 16,000 ppm in diet M: 0, 1000, 2202 or 4555 mg/kg/day F: 0, 1467, 2735 or 5953 mg/kg/day NOAEL not established in this study (<1000 mg/kg/day) LOAEL = 1000 mg/kg/day (males) and 1467 mg/kg/day (females), based on decreased body weight gains.

870.3200 21 - Day

dermal toxicity (Ne w Zealand White rabbit) 44342905 (1990)

Acceptable/guideline 0, 200 or 1000 mg/kg/day applied to skin daily for 21 days. NOAEL = 1000 mg/kg/day (limit dose) LOAEL not established in this study (> 1000 mg/kg/day).

870.3700a Prenatal

developmental in (Wistar rat) 41063524 (1987)

**Acceptable/guideline** 0, 24.4, 146 or 438 mg/kg/day (gavage) **Maternal** NOAEL = 146 mg/kg/day LOAEL = 438 mg/kg/day based on increased mo rtality, decreased food consumption and increased water consumption. **Developm ental**  NOAEL ≥438 mg/kg/day LOAEL not established in this study (> 438 mg/kg/day).Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 63 of 80 **Table A.2.2 Subchronic, Chronic and**  **Other Toxicity Profile –**  **Quinclorac Guideline**  **No. Study Type**  **MRID No. (year)/ Classification /Doses**  **Results** 870.3700b Prenatal

developmental in (Himalayan rabbit) 41063525 (1986),

41680501 (1990) Acceptable/guideline 0, 70, 200 or 600 mg/kg/day (gavage) **Materna** l NOAEL = 70 mg/kg/day LOAEL = 200 mg/kg/day based on decreased body weight gain and food consumption (and increased water consumption). **Developm enta**  l NOAEL = 200 mg/kg/day LOAEL = 600 mg/kg/day based on increased resorption rate, postimplantation loss, decreased live fetuses and reduced fetal body weight. 870.3800 Reproduction and

fertility effects (Wistar rat) 41063526 (1988);

41874201, - 02 (1991, 1988); 41910001 (1991) Acceptable/guideline 0, 1000, 4000 or 12,000 ppm in diet 0, 40, 160 or 480 mg/kg/day **Parental/System ic**  NOAEL = 160 mg/kg/day LOAEL = 480 mg/kg/day based on reduced body weight in both sexes during premating and lactation periods. **Reproductive** NOAEL = 480 mg/kg/day LOAEL not established in this study (> 480 mg/kg/day). **Offspring** NOAEL = 160 mg/kg/day LOAEL = 480 mg/kg/day based on decreased pup weight, developmental delays and possible marginal effect on pup viability. 870.4300 Com

bined chronic toxicity/ carcinogenicity (Wistar rat) 41063522 (1988);

42012901, - 02 (1991) Acceptable/guideline 0, 1000, 4000, 8000 or 12,000 ppm in diet M: 0, 56, 186, 385 or 487 mg/kg/day F: 0, 235, 478 or 757 mg/kg/day NOAEL = 385 mg/kg/day (males and 478 mg/kg/day (females) LOAEL = 487 mg/kg/day (males) based on increased incidence of pancreatic acinar cell hyperplasia and 757 (females) based on decreased body weight. **Equivocal increase in pancreatic acinar cell adenom**  **as in males.** 870.4100b Chronic toxicity

(Beagle dog) 41123201 (1987)

**Acceptable/guideline** 0, 1000, 4000 or 12,000 in diet M: 0, 34, 142 or 513 mg/kg/day F: 0, 35, 140 or 469 mg/kg/day NOAEL = 142 mg/kg/day (males) and 140 mg/kg/day (females) LOAEL = 513 mg/kg/day (males) and 469 mg/kg/day (females) based on decreased body weight gain and food efficiency, increased liver and kidney weights, decreased HgB, RBC, MCH and MCV and kidney degeneration. 870.4200 Carcinogenicity

(B6C3F1/Crl Br mo use) 41063523 (1988)

Acceptable/guideline 0, 250, 1000, 4000 or 8000 ppm in diet M: 0, 37.5, 150, 600 or 1200 mg/kg/day NOAEL = 37.5 mg/kg/day LOAEL = 150 mg/kg/day based on decreased body weight in males and females. **No evidence of carcinogenicity.** Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 64 of 80 **Table A.2.2 Subchronic, Chronic and**  **Other Toxicity Profile –**  **Quinclorac Guideline**  **No. Study Type**  **MRID No. (year)/ Classification /Doses**  **Results** 870. 5100 Bacterial reverse

gene mutation Ames assay S. typhimurium 41063527 (1984)

Acceptable/guideline Dose range 0 to 5000 μg/plate with and without S9 Negative up to the limit dose (5000 μg/plate) with or without S9 in S. typhimurium strains TA 98, TA100, TA1535, TA1537

870.5100 Bacterial reverse

gene mutation S. typhimurium/E.coli 41063528 (1988)

Acceptable/guideline Dose range 0 to 5000 μg/plate with and without S9 Negative up to the limit dose (5000 μg/plate) with or without S9 in S. typhimurium strains TA 98, TA100, TA1535, TA1537 and E. coli strain WP2 uvrA 870.5300 In vitro mammalian

forward gene mutation, CHO cells/HGPRT locus 41680503 (1989)

Acceptable/guideline Dose range 0 to 2150 μg/mL with or without S9 Negative for gene mutations up to cytotoxic doses (2000 μg/mL) with or without S9.

870.5375 In vitro mammalian

chromosome aberration assay, human lymphocytes 41076103 (1986)

Acceptable/guideline Dose range 125 to 1500 μg/mL without S9 and 250 to 2500 μg/mL with S9 Positive for chromosomal aberrations but only at cytotoxic concentrations (2000 μg/mL with S9 and 1000 μg/mL without S9).

870.5385 Cy

togenetics

– in vivo mo use micronucleus assay 41063530 (1989)

Acceptable/guideline Single gavage doses up to 1000 mg/kg Negative in male and female NMRI mice at all doses up to limit dose (1000 mg/kg). Mid and high dose groups showed clinical signs of toxicity (irregular br eathing, apathy, piloerection) but no toxicity to target cell was observed. 870.5550 Unscheduled DNA

synthesis in primary rat hepatocytes 41063531 (1986)

Acceptable/guideline Dose range 0 to 1520 μg/mL Negative up to cytotoxic dose (1520 μg/mL).

870.7485 Metabolism and

pharmacokinetics (rat) - biodisposition 41063533 (1987)

Acceptable/guideline Single gavage doses of 15 or 600 mg/kg of 14 C quinclorac; 14 daily gavage doses of unlabeled quinclorac following by a single dose of 14 C quinclorac Quinclorac was rapidly absorbed and eliminated primarily in the urine (91 - 98% of dose) with small amounts (1 - 4%) eliminated in the feces by day 5 after dosing. No radioactivity was detected in exhaled air.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 65 of 80 **Table A.2.2 Subchronic, Chronic and**  **Other Toxicity Profile –**  **Quinclorac Guideline**  **No. Study Type**  **MRID No. (year)/ Classification /Doses**  **Results** 870.7485 Metabolism and

pharmacokinetics (rat)

– Biliary excretion studies 41063533 (1987)

Acceptable/guideline Single gavage doses of 15 or 600 mg/kg 14 C quinclorac Biliary excretion was significant (11.5 to 14.5% of dose) at 600 mg/kg but was reabsorbed from the intestine and eliminated in the urine . 870.7485 Metabolism and

pharmacokinetics (rat)

– Plasma level studies 41063533 (1987)

Acceptable/guideline Single gavage doses of 15, 100, 600 or 1200 mg/kg Multiple gavage doses of 15 or 600 mg/kg/day 14 C quinclorac for 7 days. Mean residues were detected in plasma 30 minutes postdosing following all dose regimens. Quinclorac is poorly metabolized: mo st of radioactivity was the parent compound. Peak plasma levels of radioactivity after 7 days of dosing at 600 or 1200 mg/kg/day were observed between 7 to 48 hrs postdosing. 870.7485 Metabolism and

pharmacokinetics (rat)

– Tissue level studies 41063533 (1987)

Acceptable/guideline Multiple gavage doses of 14 C - quinclorac 15 or 1200 for 7 days. The highest concentrations of radioactivity in tissues were found at 30 minutes after the final dose for low

and high doses. Significant tissue levels were not observed ( ≤0.45% of dose), with highest levels observed in the thyroid, bone marrow

and adrenal. Tissue levels were slightly greater in females. 870.7800 Immunotoxicity

female C57BL/6 J Rj mice (8/group) 48346101 (2010)

Acceptable/guideline 0 (control), 500, 1500, or 5000 ppm (equivalent to 0, 176, 439, or 1760 mg/kg bw/day, for 28 days Immunotoxicity NOAEL is 5000 ppm (equivalent to 1760 mg/kg/day, the highest dose tested and above the limit dose); LOAEL was not established.

**A.3 Hazard Identification and Endpoint Selection**  **A.3.1 Acute Reference Dose (aRfD)**  **- Females age 13**  **- 49**  **Study Selected:**  Developmental toxicity study in rabbits **MRID No.:** 41063525; 41680501 **Executive Summary:** Ina developmental toxicity study (MRID# 41063525), quinclorac (98.3% a.i.) was administered to fifteen female Himalayan Rabbits by gavage at dose levels of 0, 70, 200, or 600 mg/kg/day

from gestational day s 7

– 19, inclusive. Maternal toxicity , observed at 200 mg/kg/day , was manifested as decreased body weight gain (36%) and food consumption (13%) during the dosing period. Additional findings noted at 600 mg/kg/day , included increased water consumption (7% over entire gestation), increasedQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 66 of 80 incidence of clinical signs (reduced/no defecation, diarrhea, apathy and poor general state) and mortality and discoloration of the kidney . **The maternal LO A** **EL is 200 mg/ kg/day, based on**  **decreased body weight gains and food consumption. The maternal NO A** **EL is 70 mg/kg/day.**  Developmental toxicity, observed at 600 mg/kg/day consisted of increased rate of resorption and post - implantation loss, a decrease in the number of live fetuses, and reduced fetal body weight. **The NO A** **EL for developmental toxicity is 200 mg/kg/day. Dose and Endpoint for Risk Assessment:**  Developmental NO AEL= 200 mg/kg/day based on increased rate of resorption and post - implantation loss, a decrease in the number of live fetuses, and reduced fetal body weight at 600 mg/kg/day (LO AEL). **Comments about Study/Endpoint:** The developmental effects are presumed to occur after a single exposure (dose) and thus were considered to be appropriate for this (acute) ri sk assessment. This dose/endpoint is applicable only to Female 13 to 49 years old. **Uncertainty Factor (UF) :**  100 (10 x for inter - species extrapolation and 10x for intra - species variability , FQPA SF = 1x ).

= 200 mg / kg / da y ( NO AEL ) ( ) = 2

. 0 mg / kg

= 2 mg / kg / day ( aRfD ) ( ) = 2

. 0 mg / kg **A.3.2 Acute Reference Dose (aRfD)**  **- General Population**  An endpoint for acute dietary exposure to the general population was not selected because there was no single dose endpoint available in the database that was appropriate for this scenario **A.3.3 Chronic Reference Dose (cRfD**  **) `**  **Study Selected:** Oncogenicity Feeding Study

in Mice **MRID No.:** 41063523 **Executive Summary:** Ina carcinogenicity study (MRID# 41063523), B6C3F1/Crl Br mice (60 sex/dose) were administered via diets with Quinclorac (97.4 or 98.3% a.i) at dose levels of 0, 250, 1000, 4000, or 8000 ppm (equivalent to 0, 37.5, 150, 600 or 1200 mg/kg/day) for 6 months or 78 weeks. Ten mice were terminated at 6 months. T he remainders were continued on the test material for 18 months. At the end of 13 weeks, body weights in males and females receiving 8000 ppm were significantl y lower than controls by 9.6% and 7.4%, respectively. Body weights in males and females receivi ng 1000, 4000, and 8000 ppm for 78 weeks were significantly lower than controlsQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 67 of 80 (7.9 to 15.9% for males; 14.3 to 17.9 for females. Treatment - related body weight reductions compared to controls were also noted in satellite males and females receiving 4000 and 8000 ppm for 6 months. Absolute liver weights were significantly reduced in male and female mice receiving 8000 ppm for 78 weeks, but there was no effect on liver- to - body weight ratio. Absolute kidney

weights were decreased in males receiving 1000, 4 000, and 8000 ppm and in females receiving 4000 and 8000 ppm for 78 weeks. Relative kidney weights were decreased in males receiving 1000, 4000, and 8000 ppm for 78 weeks. Dose - related increases in relative brain weights seen in males and females receiving 1000, 4000, and 8000 ppm. Absolute liver weights were also reduced in males receiving 4000 and 8000 ppm for 6 months, while absolute kidney weights were reduced in all treated males. A slight decrease in hematocrit values was noted in males and female s receiving 8000 ppm for 6 months, but not 78 weeks. Effects on other hematological parameters were not of biological significance. There was no effect of dosing on mortality , food consumption, or clinical signs. The LOAEL is 1000 ppm (150 mg/kg/day) ba sed on effects on body weight. The NOAEL is 250 ppm (37.5 mg/kg/day). A maximum tolerated dose (MTD) was approached based on decreased body weights in males and females receiving 8000 ppm. No evidence of histopathological or neoplastic lesions attributa ble to administration of any dose of Quinclorac was found in any tissue of any

mouse. **Dose and Endpoint for Establishing RfD:** NO AEL= 37.5 mg/kg/day based on decreased body weights seen at 150 mg/kg/day (LO AEL). **Comments about Study/ Endpoint:** The endp oint selected from the mouse carcinogenicity study is appropriate for both the population and the duration of exposure. The NOAEL from this study is the lowest NOAELin the database and therefore protective of all other effects. Uncertainty Factor(s): 100 (10 x for inter - species extrapolation and 10x for intra - species variability ; FQPA SF = 1X ).

= 37 . 5 mg / kg / da y ( NO AEL ) ( ) = 0

. 38 mg / kg / da y

= 0 . 375 mg / kg / day ( cRfD ) ( ) = 0

. 38 mg / kg / day

**A.3.4 Incidental Oral Exposure**  **(Short -**  **and Intermediate -**  **Term) Study Selected:**  Developmental toxicity study in rabbits. **MRID Nos.:** 41063525; 41680501 **Executive Summary:** See Appendix A, §870. 3700bQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 68 of 80 **Dose and Endpoint for Risk Assessment:** Maternal NO AEL= 7 0 mg/kg/day based on decreased body

weight gains and food consumption accompanied with increased water consumption at 200 mg/kg/day (L O AEL). **Comments about Study/Endpoint:** This endpoint of toxicity occurred after short exposures to quinclorac and is suitable for this exposure scenari o . A margin of exposure (MOE) of 100 is applied to account for inter - species extrapolation ( 10x ) and for intra - species variability ( 10x ) . **A.3.5 Dermal Exposure (Short**  **- , Intermediate**  **- and Long**  **- Term** **)** A dermal endpoint was not selected because an appropriate endpoint was not available (no dermal toxicity

was seen at the limit dose of 1000 mg/kg/day in a 21 - day

dermal toxicity

study). Also, there are no susceptibility concerns . **A.3.6 Inhalation Exposure (Short** **- , Intermediate**  **- and Long**  **- Term)**  **A.3. 7**  **Inhalation Exposure (Short and Intermediate**  **- Term)**  **Selected Study:** Developmental toxicity study in rabbits. **MRID Nos.:** 41063525; 41680501 **Executive Summary** : See Appendix A, §870. 3700b **Dose and Endpoint for Risk Assessment:** Maternal NO AEL= 7 0 mg/kg/day based on decreased body weight gains and food consumption accompanied with increased water consumption at 200 mg/kg/day (L O AEL). **Comments about Study/Endpoint:** This endpoint of toxicity occurred after short exposures to quinclorac and is sui table for this exposure scenario . A margin of exposure (MOE) of 100 is applied to account for inter - species extrapolation ( 10x ) and for intra - species variability ( 10x ) . **A.3.7 Inhalation Exposure**  **( Long**  **- Term)**  Not applicable. Long - term inhalation exposure is not anticipated under current use scenarios .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 69 of 80 **A.4 Executive Summaries**  **A.4.1 Subchronic Toxicity**  **870.3100 90**  **- Day Oral Toxicity**  **- Rat**  In a subchronic toxicity

study (M RID 41063516), Quinclorac (96.5% a.i.) was administered to 10 Wistar Chhb - THOM (SPF) rats/sex/dose in diet, at dose levels of 0, 1000, 4000, or 12000 ppm (0, 76.8, 302.3 or 929.9 mg/kg/day for males and 0, 86.7, 358.0 or 1035.4 mg/kg/day for females). There were no deaths occurred. No compound rel ated clinical signs of toxicity were observed. The LO AEL is 12,000 ppm (males 929.9 and females 1035.4 mg/kg/ day), based on decreases in body weight gain, food consumption and an increase in water intake in males and females, and decrease in monocy tes in f emale, increases in SGOT and SGPT in males, and pathological changes in kidney s of males (slight to minimal focal chronic interstitial nephritis. The NO AEL is 4000 ppm (males 302.3 and females 358.0 mg/kg/ day). This subchronic toxicity

study is classifie d unacceptable/non - guideline due to lack of information on the purity of the test material and information on stability and homogeneity

of the test substance in the diet. **870.3100 90**  **- Day Oral Toxicity**  **- Mouse**  In a subchronic toxicity

study (M RID 41063518), Quinclorac (98.29% a.i.) was administered to 10 B6C3F1/Crl BR mice/sex/dose in diet, at dose levels of 0, 4000, 8000, or 16000 ppm (0, 1000, 2202 or 4555 mg/kg/day for males and 0, 1467, 2735 or 5953 mg/kg/day for females). N o deaths occurred. No compound related clinical signs of toxicity were observed. At 8000 and 16000 ppm there was an increase in water intake in males and females and BUN in males. There was decreased kidney

weight in males and females and relative kidney weight in males in the 16,000 ppm group. At 4000 ppm there was decreased body weight gain in males and females. The LO AEL is 4,000 ppm (males 1,000 and females 1467 mg/kg/day), based on decreases in body weight. The NO AEL was not established. This subchronic toxicity

study is classified A cceptable/non - guideline requirement for a subchronic oral study

(82 - 1) in mice. However taken with MRID 41063519, it is acceptable/ guideline. In another subchronic toxicity study (MRID 41063519), Quinclorac (98.29% a.i.) was administere d to 10 B6C3F1/Crl BR mice/sex/ dose in diet, at dose levels of 0 or 500 ppm (75 mg/kg/day , HDT). No deaths occurred. No compound related clinical signs of toxicity were observed. Females in th e 500 ppm group had slightly (although statistically

significant) reduced body weights when compared to controls on day 98. This decrease was minimal and is not believed to be compound related since body weights were not significantl y different at any other time intervals. The NO A ELis 500 ppm (75 mg/kg/day). This subchronic toxicity

study is classified Unacceptable because onl y one dose level was tested . However taken with MRID 41063518, it is acceptable /guideline.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 70 of 80 **870.3150 90**  **- Day Oral Toxicity**  **- Dog**  The data requirement for a dog 90 - day subchronic oral to xicity

is satisfied by

the 1 - ye ar dog chronic oral study . **870.3200 21/28**  **- Day Dermal Toxicity**  **– Ra**  **bbit** In a twenty- one day

dermal toxicity

study (MRID 44342905), Quinclorac (98.29% a. I.) in 0.5% carbox ym eth ylcellulose was applied dermally to 5 New Zeal and White (KFM) albino rabbits/sex/dose at dose levels of 0, 40, 200 and 1000 mg/kg/day for 7 days a week for 3 weeks. The hair was clipped from the dorsal surface prior to treatment and once a week during the study. Test material was applied daily for 3 w eeks to an area of skin approximately 10% of the total body surface area on the back of each rabbit and covered with a semi - occlusive gauze. After 6 hour exposure, the excess test material was removed from the treated area with a luke - warm water and kept o pen until next application. Vehicle control group received 2 m l/kg b.w of 0.5% carbox ym eth ylcellulose in water, while test groups received suspension of test material in aqueous 0.5% carbox ym ethyl cellulose (2 ml/kg/b.w). There was no treatment - related c linical observations, changes in body weight gain, food consumption, histopathologic findings or hematologic or blood chemistry parameters after a 21 day (7 day s/week) repeated application of Quinclorac at a nominal concentrations of 0, 40, 200 or 1000 mg/kg/day in 0.5% carbox ym ethyl cellulose. The limit dose is 1000 mg/kg/day . No mortality occurred at any dose level tested. No local skin irritation was reported during the study. The NO AEL ≥ 1000 mg/kg/ day , Limit Dose, (HDT; males and females). The LO AEL >10 00 mg/kg/ day ( H DT; males and females). This study

is classified as Acceptable/ Guideline and does satisfy the guideline requirements for a 21 - day repeated dermal toxicity

study in rabbits (82 - 2). **870.3465 90**  **- Day Inhalation**  **– Rat**  The requirement of a 28 - day i nhalation t oxicity s tudy was waived based on low volatility, low acute inhalation toxicity

and large extrapolated inhalation MOE ( D376603 , 23 September 2010) . **A.4.2 Prenatal Developmental Toxicity**  **870.3700a Prenatal Developmental Toxicity Study**  **- Rat**  In a developmental toxicity study (MRID # 41063524), Quinclorac (96.5% a.i.) was administered to twenty- five female Wistar rats by gavage at dose levels of 0, 24.4, 146, and 438 mg/kg/day

from gestational days 6 - 15, inclusive. Maternal toxicity , observed at 438 mg/kg/day , was manifested as decreased food consumption (10 - 15%) and increased water consumption (31 - 54%) during the dosing and/or gestation period as well as mortality . The maternal LOAEL is 438 mg/kg/day , based on decreased food consumption, increased water consumption and mortality . The maternal NOAEL is 146 mg/kg/day . No developmental toxicity was observed. The LOAEL for developmental toxicity is >436 mg/kg/day . The developmental NOAEL is ≥436 mg/kg/day .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 71 of 80 This study is classified as Acceptable/Guideline and satisfies the guideline requirement for a developmental toxicity

study in rats . **870.3700b Prenatal Developmental Toxicity Study -**  **Rabbit** In a developmental toxicity study (MRID# 41063525), Quinclorac (98.3% a.i.) was administered to fifteen female Himalayan Rabbits b y gavage at dose levels of 0, 70, 200, or 600 mg/kg/day from gestational day s 7

– 19, inclusive. Maternal toxicity, observed at 200 mg/kg/day , was manifested as decreased body weight gain (36%) and food consumption (13%) during the dosing period. Additional findings noted at 600 mg/kg/day, included increased water consumption (7% over entire gestation), increased incidence of clinical signs (reduced/no defecation, diarrhea, apath y and poor general state) and mortality and discoloration of the kidney. The maternal LOAEL is 200 mg/kg/day, based on decreased body weight gains and food consumption. The maternal NOEL is 70 mg/kg/day . Developmental toxicity, observed at 600 mg/kg/day consisted of increase d rate of resorption and post - implantation loss, a decrease in the number of live fetuses, and reduced fetal body weight. The NOAELfor developmental toxicity is 200 mg/kg/day . This study

is classified as Acceptable/Guideline and satisfies the guideline requirement for a developmental toxicity study (83 - 3b) in rabbits. **A.4.3 Reproductive Toxicity**  **870.3800 Reproduction and Fertility Effects -**  **Rat** In a 2 - generation reproduction study (MRID # 41063526), Quinclorac (≥97.3% a.i.) was administered to Wistar rats (24/sex/group) at dietary levels of 0, 1,000, 4,000 or 12,000 ppm (0, 40, 160 or 480 mg/kg/day, respectivel y). Parental toxicity : Evidence of toxicity was observed in the parental rats at 12,000 ppm (480 mg/kg/day). F l males showed reduced mean body weight during premating, which largel y reflected their decreased weights as pups at weaning (at week 0 , - 24%, p< 0 .0l, becoming less pronounced at week 18, - 6% below controls, p< 0.05 ). F 0 males showed no effects. F 0 females showed a small but statistically significant decrease in mean body weight at Week 24 of premating ( - 4%, p< 0.05 ) but not at earlier times. F 1 females had decreased body weights during premating (at Week 18, - 12%; p< 0.01 ): as with males, part of the decrease reflected smaller weights at weaning. During gestation, decreases of about - 6% in mean body weight at Day

20 were observed for the F 0 females in the second mating (p< 0.01 ) and the F l females in their onl y mating (p< 0.05 ). However, in the second mating of F 0 females, there was no significant effect. The F 0 (first mating only) and F l females showed reduced body weights during part or all of lactation (up to - 10% below controls). In addition to body weight changes, an increased incidence of interstitial nephritis was observed in F 0 and F l females. The parental s ys temic toxicity L OAEL is 12,000 ppm (480 mg/kg/day), based on decreased body weight during premating and lactation. The NOAEL is 4000 ppm (160 mg/kg/ day). Reproductive toxicity : No effects on reproducti ve parameters were observed. The reproductive toxicity NOAEL is 12,000 ppm (480 mg/kg/day). A reproductive toxicity LOAEL was not established (>480 mg/kg/day).Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 72 of 80 Offspring toxicity : At 12,000 ppm (480 mg/kg/day), the major effect on pup growth and development was observed during lactation. Decreased pup weights were observed in male and female F l and F 2 pups during lactation (at Day 21 of lactation, 15 - 26% below controls; all generations p< 0 .0 1) and delayed ph ys ical development (delayed pinna unfolding and eye opening) was also observed. Decreased pup weight at L actation Day 0 was seen only

in the F 2 male and female pups (approximately 7% below controls), a dose also associated with a slight decrease in maternal weight during gestation. Slightly decreased pu

p viability

and survival were reported; however, these effects were marginal (<6%), not seen in all offspring generations and did not achieve statistical significance. The relationship to treatment of this finding is considered equivocal. The offspring LOAEL is 12,000 ppm (480 mg/kg/day), based on effects on pup growth with a possible marginal effect on pup viability . The offspring NOAELis 4000 ppm (160 mg/kg/day). This study

is classified as Acceptable/guideline and satisfies the guideline requirement for a multigeneration reproductive toxicity study in the rodent (870.3800). **A.4.4 Chronic Toxicity**  **870.4100a (870.4300) Chronic Toxicity –**  **Rat** The combined chronic/ carcinogenicity study satisfies this requirement. **870.4100b Chronic Toxicity -**  **Dog** In a 1 - ye ar feeding study in dogs (MRID 41123201), Quinclorac (97.4% a .i .) was administered to groups of 6 male and 6 female beagle dogs at dietary levels of 0, 1000, 4000 or 12000 ppm (equivalent to 0, 34, 142, or 513 mg/kg/day for males and 0, 35, 140, or 469 mg/kg/day for females) for 12 months. No effect on mortality was observed. Administration of 12000 ppm resulted in lower mean body weight, compared with control, reduced body weight gain and an adverse effect on food efficiency . There was a marginal reduction of body weight gain and food efficiency in male dogs fed 4000 ppm of test substance. In male dogs fed 12000 ppm of test substance, there were significant (<0 .01) treatment - related reductions in hemoglobin concentration, ery

throcy te count, and hematocrit, mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) values. In females fed 12000 ppm of test substance, significant reductions (p <0.05 or p < 0.01) were seen in hemoglobin concentration, MCH, and MCV at all study intervals (weeks 13, 26, and 52), hematocrit at weeks 26 and 52 and ery throcy te count at week 26. In females fed 4000 ppm test substance, significant reductions (p <0.05) were seen at w eek 26 in hemoglobin concentration, ery throcy te count, and hematocrit. Administration of 12000 ppm of test substance resulted in decreases in a number of clinical chemistry parameters; however, significant (p <0.01) changes were noted only for creatinine, calcium, and albumin. However, it should be noted that, in most cases, clinical adverse effects are only associated with increased values for these parameters. At the 12000 ppm dose level, increase in absolute (p <0.01 for males) and relative liver weights (p <0.01 for both males and females) were observed for both sexes. Relative liver weights also were significantly increased (p <0.05) in females of the 4000 and 1000 ppm groups. Relative kidney weights were significantl y increased (p <0.01) inQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 73 of 80 both males and females of the 12000 ppm group and in males of the 4000 ppm group. There were no histopathologic correlates to account for the increased organ weights. Histopathologic findings in the liver were limited to an increase in focal mononuclear infiltration and to single cell necrosis in two dogs in the 12000 ppm group. Hydropic degeneration of the kidney was seen in two males and two females of the 12000 ppm group . The LO AEL is 12000 ppm (513 mg/kg/day- males, 469 mg/kg/day- females) based on the reduced body weight gain, adverse effect on food efficiency , hematological and clinical chemistry values, increased liver and kidney weights, and microscopic findings. The NO AEL is 4000 ppm (142 mg/kg/day for males and 140 mg/kg/day for females). This study

is classi fied as Acceptable/Guideline and satisfies the guideline requirement for a feeding study (83 - 1) in dogs. **A.4.5 Carcinogenicity**  **870.4200a Carcinogenicity Study -**  **rat** In a combined chronic toxicity /carcinogenicity study

(MRID# 41063522), Wistar (chbb - THOM) rats (80/sex/group) were administered via diets with Quinclorac (97.4% a.i.) at dose levels of 0, 1000, 4000, 8000, or 12000 ppm (equivalent to 0, 56, 186, 385, or 487 mg/kg/day for males and 0, 60, 235, 478, or 757 mg/kg/day for females, respective ly). Ten rats/sex/group were terminated at 12 months. The remainders were continued on the test material for 24 months. Body weights were slightly

reduced in females received 12000 ppm when compared to the control. No effects were seen on survival, food co nsumption, clinical signs of toxicity, clinical laboratory findings, organ weight, or gross or histologic findings. For females, the LOEL was 12000 ppm based on slight decreases in mean body weight and the NOELwas 8000 ppm. For males, the LOEL was not est ablished and the NOELwas 12000 ppm (the highest dose tested). This study was originall y classified as supplementary (upgradeable) because a maximum tolerated dose (MTD) was not established for the carcinogenicity part of the study ; in addition, there was a probability of misdiagnosis of microscopic findings caused by tabulation of NAD (no abnormalities detected) for tissues in several animals with severe postmortem autoly sis. Additional data (MRID# 42012901, 42012902) were submitted to the Agency in whi ch adequatel y addressed the deficiencies described above. For chronic toxicity , the LOEL was estimated to be 12000 ppm (487 mg/kg/day for males and 757 mg/kg/day for females) based on slight decrease in body weight in females and an increase in acinar cell hy perplasia of the pancreas in males. The NOELwas 8000 ppm (385 mg/kg/day for males and 478 mg/kg/day for females). For carcinogenicity , the data indicate an increase in acinar cell hyperplasia of the pancreas in males at 12000 ppm (35%) when compared to controls (5.7%). In addition, there was an increase in the incidence of acinar cell adenoma of the pancreas in males in the 12000 ppm group (20%) when compared to the control (1.4%). The study was upgraded to acceptable and satisfies guideline requirem ent for a combined chronic toxicity

/carcinogenicity

study in rats (83 - 5). **870.4200b Carcinogenicity (feeding) -**  **Mouse**Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 74 of 80 In a carcinogenicity

study (MRID# 41063523), B6C3F1/Crl Br mice (60 sex/dose) were administered via diets with Quinclorac (97.4 or 98.3% a.i) at dose levels of 0, 250, 1000, 4000, or 8000 ppm (equivalent to 0, 37.5, 150, 600 or 1200 mg/kg/day) for 6 months or 78 weeks. Ten mice were terminated at 6 months. The remainders were continued on the test material for 18 months. At the end of 13 weeks, body weights in males and females receiving 8000 ppm were significantl y lower than controls by 9.6% and 7.4%, respectively. Body weights in males and females receivin g 1000, 4000, and 8000 ppm for 78 weeks were significantly lower than controls (7.9 to 15.9% for males; 14.3 to 17.9 for females. Treatment - related body weight reductions compared to controls were also noted in satellite males and females receiving 4000 a nd 8000 ppm for 6 months. Absolute liver weights were significantly reduced in male and female mice receiving 8000 ppm for 78 weeks, but there was no effect on liver- to - body weight ratio. Absolute kidney

weights were decreased in males receiving 1000, 40 00, and 8000 ppm and in females receiving 4000 and 8000 ppm for 78 weeks. Relative kidney weights were decreased in males receiving 1000, 4000, and 8000 ppm for 78 weeks. Dose - related increases in relative brain weights seen in males and females receivin g 1000, 4000, and 8000 ppm. Absolute liver weights were also reduced in males receiving 4000 and 8000 ppm for 6 months, while absolute kidney weights were reduced in all treated males. A slight decrease in hematocrit values was noted in males and females receiving 8000 ppm for 6 months, but not 78 weeks. Effects on other hematological parameters were not of biological significance. There was no effect of dosing on mortality , food consumption, or clinical signs. The LOEL is 1000 ppm (150 mg/kg/day) base d on effects on body weight. The NOEL is 250 ppm (37.5 mg/kg/day). A maximum tolerated dose (MTD) was approached based on decreased body weights in males and females receiving 8000 ppm. No evidence of histopathological or neoplastic lesions attributable to administration of any dose of Quinclorac was found in any tissue of any

mouse. This study

is classified as Acceptable/Guideline and satisfies the guideline requirement for a carcinogenicity

study (83 - 2) in mice. **A.4.6 Mutagenicity**  **Gene Mutation** 870. 5100 Bacterial reverse gene mutation 41063527 Acceptable/Guideline Negative up to the limit dose (5000 μg/plate) with or without S9 in S. typhimurium strains TA98, TA100, TA1535, TA1537 870. 5100 Bacterial reverse gene mutation 41063528 Acceptable/Guideline Negative up to the limit dose (5000 μg/plate) with or without S9 in S. typhimurium strains TA98, TA100, TA1535, TA1537 and E. coli strain WP2uvrAQuinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 75 of 80 **Cytogenetics** OPPTS 870.5385 In vivo bone marrow cy

togenic assay MRID 41063530. Acceptable/Guideline Quinclorac was not clastogenic in this in vivo test. Negative in male and female NMRI mice at all doses up to limit dose (1000 mg/kg). Mid and high dose groups showed clinical signs of toxicity

(irregular breathing, apathy , piloerecti on) but no toxicity

to target cell was observed. OPPTS 870.53 9 5 In vivo m icronucleus assay in mice. MRID 410635 29 . Acceptable/Guideline Quinclorac did not induce clastogenic or aneugenic at any dose (500, 1000 or 2000 mg/kg) or sacrifice time. Toxic signs of irregular breathing, apathy , and piloerection were noted in the mid - and high - dose groups. **Other Genotoxicity** 870.5300 , In vitro mammalian forward gene mutation, CHO cells/HGPRT locus MRID 41680503 Acceptable/guideline Negative for gene mutations up to cy totoxic doses (2000 μg/mL) with or without S9.

870.5300 , In vitro mammalian chromosome aberration assay , human ly mphocy tes MRID 41076103 Acceptable/guideline Positive for chromosomal aberrations but only at cy totoxic concentrations (2000 μg/mLwith S9 and 1000 μg/mL without S9).

870.5550 , Unscheduled DNA sy nthesis in primary

rat hepatocy tes MRID 41063531 Acceptable/guideline Negative up to cy totoxic dose (1520 μg/mL).

**A.4.7 Neurotoxicity**  **870.6100 Delayed Neurotoxicity Study –**  **Hen** Not required . **870.6200 Acute Neurotoxicity Screening Battery -**  Waived ( HASPOC TXR 0056385 )Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 76 of 80 **870.6200 Subchronic Neurotoxicity Screening Battery** Waived ( HASPOC TXR 0056385 ) **870.6300 Developmental Neurotoxicity Study** HED HIARC did not recommend a DNT study. (TXR 0012902) **A.4.8 Metabolism**  **870.7485 Metabolism**  **- Rat**  The metabolism of quinclorac ([2,3,4 - 14 C)3,7

—dichloro - 8 - quinolinecarboxylic acid) following oral administration was studied extensively in male and female CD rats (MRID 41063533) . The compound was rapidl y absorbed and eliminated in the urine following administration of sin gle oral doses of [ 14 C ] quinclorac at 15 or 600 mg/kg and at 15 mg/kg after the animals were dosed with unlabe le d quinclorac at 15 mg/kg/day for 14 day s. Elimination in the urine 5 day s after dosing accounted for 91 to 98 % of the dose with only 1 to 4 % eli minated in the feces. No radioactivity

was detected in expired air. Biliary excretio n was significant (11.5 to 14.5% of the dose) in animals receiving 600 mg/kg. However, most of this radioactivity was reabsorbed from the intestines and eliminated in the urine. Most of the radioactivity in the bile is associated with the glucuronide conjugate of quinclorac. The conjugate is apparently hydroly zed in the intestines and reabsorbe d . Almost all the radioactivity in the urine is unchange d quinclorac. Radioactive tissue residue levels 5 days after do si ng were dose - dependent. Results from these and other (whole - body

autoradiography

and time - course) studies indicate that quinclorac may accumulate in the adrenal glands, bone marrow, thyr oid, squamous epithelium of the non - fundic stomach, and ovaries. In 7 - day

time - course studies (oral gavage at 15 mg/kg/day or dietary

at about 1,000 mg/kg/day) maximum 14 C residue levels were detected 30 minutes after the final dose; thereafter, residue levels decreased with time. Mean 14 C residues in plasma were also detected at 30 minutes in animals receiving single oral doses of 15, 100, or 600 mg/kg or 15 mg/kg/day for 7 day s. Elimination was biphasic with half - lives of 3 to 4 hours for the rapid phase at the low doses and a half - li fe of about 13 hours at 600 mg/kg. Peak plasma levels of radioactivity in animals receiving higher doses (1200 mg/kg or 600 mg/kg/day for 7 day s) were noted for 7 to 48 hours postdosing: saturation kinetics were also noted at these higher doses. These studies are acceptable and fulfill EPA’ s guidelines series 85 - 1. **870.7600 Dermal Absorption**  **- Rat**  Dermal absorption studies are not available. **A.4.9 Immunotoxicity**  **870.7800 Immunotoxicity**  In an immunotoxicity

study (MRID 48346101 ), Quinclorac (BAS 514 H, 99.9% a.i., Batch# 479 - 480) was administered to female C57BL/6 J Rj mice (8/group) in the diet at dose levels of 0Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 77 of 80 (control), 500, 1500, or 5000 ppm (equivalent to 0, 176, 439, or 1760 mg/kg bw/day, respectivel y) for 28 consecutive d ay s. Animals in the positive control group (8/group) received cyclophosphamide by

gavage at a dose of 10 mg/kg/day throughout the study . Six day s before necrops y, animals in all groups were immunized with a suspension of sheep red blood cells (4x10 8 SRBC/mL) b y intravenous injection (0.5 mL/animal dose volume). All animals were evaluated for mortality , clinical signs, body weight changes, food consumption, and gross pathology . Immunotoxicity was assessed using an Enzy me - Linked Immunosorbent Assay (ELI SA) ap proach that measured the concentration of serum anti - SRBC immunoglobulin M (IgM). The absolute and relative (to terminal body weight) organ weights of the spleen and thy mus were determined at necrops y. There were no treatment related effects on mortality , clinical signs, body weight changes, food consumption, organ weights, or gross pathology at any dose concentration that were considered treatment related. The sy stemic toxicity

NOAEL is 5000 ppm (equivalent to 1760 mg/kg bw/day); the LOAEL was not established, tested above the limit dose. For immunotoxicity, there were no treatment - related effects on serum anti - SRBC IgM antibody levels as measured b y an ELISA, or thymus and spleen weights at any diet concentration. High inter - individual variability was seen in the treatment and vehicle control groups. Examination of individual animal data did not show any trend or distribution that would demonstrate significant suppression of the anti - SRBC IgM response. The mean IgM result from positive control grou p was 79.6% lower than the vehicle control group, showing it was valid for evaluating immuno sup p ression. The positive control group confirmed the ability of the test s ys tem to detect immuno - suppressive effects and confirmed the validity of the study

design. A Natural Killer (NK) cell activity assay was not performed in this study . The toxicology database for quinclorac does not reveal any evidence of treatment - related effects on the immune sy stem. The overall weight of evidence suggests that this chemical does not directly target the immune sy stem. Under HED guidance, a NK cell activity assay is not required at this time. Under conditions of this study , the immunotoxicity NOAEL is 5000 ppm (equivalent to 1760 mg/kg/day , the highest dose tested and above the limit dose); the L OAEL was not established. This immunotoxicity

study is classified as acceptable/guideline and satisfies the guideline requirement for an immunotoxicity study (OPPTS 870. 7800) in rodents. **A.4.9 Special/Other**  **Studies** (optional section) None.Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 78 of 80 **Appendix B**  **. Review of Human Research**  This risk assessment relies in part on data from studies in which adult human subjects were intentionally

exposed to a pesticide or other chemical. These data, which include studies from the Pesticide Handlers Exposure Database Version 1.1 (PHED 1.1); the Agricultural Handler Exposure Task Force (AHETF) database; the Outdoor Residential Exposure Task Force (ORETF) database; and the Agricultural Re - entry Task Force (ARTF) database are subject to ethics review pursuant to 40 CFR 26, have received that review , and are compliant with applicable ethics requirements. For certain studies that review may have included review by the Human Studies Review Board. Descriptions of data sources as well as guidance on their use can be found at http://www.epa.gov/pesticides/science/handler- exposure - data.html and http://www.epa.gov/pesticides/science/post - app - exposure - data.html .Quinclorac Human Health Risk Assessment DP Nos. 404794, 404808

Page 79 of 80 **Appendix C**  **: International Residue Limits** 



### Quinclorac (PC Code 128974; 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 - quinolinecarb 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 b yproducts 1.5 0.05 Goat, meat 0.05 0.05 Grass, forage 150 Grass, hay 130 Hog, fat 0.7 0.05 Hog, meat b yproducts 0.05 0.05 Hog, meat 0.05 0.05 Horse, fat 0.05 0.05 Horse, meat b yp roducts 1.5 0.05 Horse, meat 0.05 0.05 Milk 0.05 0.05 Poultry , fat 0.05 0.05 Poultry , meat b yproducts 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 b yproducts 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 Human Health Risk Assessment DP Nos. 404794, 404808

Page 80 of 80 Summary of US and International Tolerances and Maximum Residue Limits Residue Definition : US Canada Mexico 1 Codex Proposed MRLs Low growing berries, except strawberries, subgroup 13 - 07H 1.5 Rhubarb 0.5 MRLs 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 b y measuring 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 12/31/12