UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

MEMORANDUM 

DATE: October9, 2014 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

SUBJECT: Oxyfluorfen: Human Health Assessment Scoping Document in Support of 

Registration Review. 

PC Code: I I 1601 

Decision No.: 489866 

Petition No.: NA 

Risk Assessment Type: NA 

TXRNo.:NA 

MRIDNo.: NA 

DP Barcode: 0419418 

Registration No.: NA 

Regulatory Action: Registration Review Scoping 

Case No.: 2490 

CAS No.: 42874-03-3 

40 CFR: § 180.38 I 

FROM: Ivan D. Nieves, Chemist/Risk Assessor 4 

Ayaad Assaad, Ph.D., Toxicologist , 7 ..9~ 

Marquea D. King, Ph.D, Toxicologi ~;q___ 

Bonnie Cropp-Kohlligian, Environmental Scientisy 

Susan Hummel, Chemist 

Risk Assessment Branch IV 

Health Effects Division (7509P) 

THROUGH: Eli

Risk 

ssa 

Assessm

Reaves, 

ent 

Ph.D., 

Branch 

Branch 

IV 

Chi efc£~ ~ 

Health Effects Division (7509P) 

TO: Benjamin Askin, Chemical Review Manager (RM 51) 

Risk Management and Implementation Branch IV 

Pesticide Re-Evaluation Division (7508P) 

Attached is the Health Effects Division's (HED) human health scoping document for oxyfluorfen 

to support the Registration Review process. 

Page 1 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Executive Summary 

The Health Effects Division (HED) has evaluated the status of the human health risk assessment 

for oxyfluorfen to determine the scope of work necessary to support Registration Review. 

The most recently completed human health risk assessment (2002; Registration Eligibility 

Decision [RED]1

) was considered as part of this seeping exercise. 

Oxyfluorfen [2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl) benzene] is a broad 

spectrum pre- and post-emergent herbicide used to control annual broadleaf and grassy weeds in 

corn, cotton, soybeans, fruit, nut trees, and ornamentals. It is registered for residential use as a 

spot treatment to kill weeds on patios, driveways and similar areas. U.S. permanent tolerances 

for residues of oxyfluorfen are established under 40 CFR § 180.381 in/on a number of crop and 

livestock raw agricultural commodities. Formulations include emulsifiable liquid products for 

agricultural use and granular products for commercial nursery use. Residential products are 

available as Ready to Use (RTU) trigger sprayer, RTU sprinkler jug or as a liquid to be applied 

in a sprinkler can or hand-carried tank sprayer. Liquid formulations are applied using 

groundboom, right-of-way and backpack sprayers. Granular oxyfluorfen might be applied with 

broadcast spreaders, belly grinder, and handheld equipment. 

The toxicity database for oxyfluorfen is adequate to support existing registrations and 

· Registration Review with the exception of the subchronic dermal toxicity study in rabbit which is 

required (TXR # 0057003). A database uncertainty factor of 1 OX will be retained for all dermal 

assessments until this requirement is met. Further, the Hazard and Science Policy Council 

(HASPOC) concludled that acute and subchronic neurotoxicity studies are not required. All 

previous doses for risk assessment purposes were assessed with uncertainty factors of 1 OX for 

interspecies extrapolation and 1 OX and intraspecies variability. An additional uncertainty factor 

of 3X was applied to intermediate-term dermal, inhalation, and incidental-oral exposures because 

this dose was derived from a LOAEL rather than a NOAEL. An oral endpoint was selected for 

both the dermal and inhalation exposure. Oxyfluorfen is classified as "Likely to be Carcinogenic 

to Humans" [Q1* = 7.32 x 10·2 (mg/kg/day)"1

). During registration review, endpoint selection, 

points of departure (PODs), and uncertainty factors (UFs)/ safety factors (SFs) for the risk • 

assessments will be re-evaluated based upon updated policies and procedures. 

The residue chemistry database is adequate. Residue chemistry data submitted since the RED 

will need to be evaluated and a tolerance for residues of oxyfluorfen in/on cotton gin byproducts 

may be established. 

There are no maximum residue limits (MRLs) for residues of oxyfluorfen by Codex or Mexico. 

Excluding Canadian MRLs with no U.S. equivalent, the remaining Canadian MRLs are fully 

harmonized with U.S. tolerances. 

An acute dietary risk assessment was not conducted because no appropriate endpoint attributable 

to a single dose was identified. There are no chronic dietary (food and water) risk estimates of 

concern for oxyfluorfen and its metabolites. A cancer dietary (food only) risk assessment 

1 http://www.epa.gov/oppsrrdl/reregistrationloxyfluorfenl 

Page 2 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

determined a risk estimate of3.8 x 10·7 for the general U.S. population. Updated dietary 

exposure assessments may be necessary under registration review if there are significant changes 

to the drinking water estimated concentrations which will be updated by EFED, or if there are 

significant changes to the PODs or UFs/SFs. 

The most current residential risk assessment did not identify risks of concern2. However, 

updates to HED's Residential SOPs3 (2012) have been made along with policy changes for body 

weight assumptions. Therefore, the residential exposure risk assessment will need to be updated 

according to current policies during Registration Review. The need for spray drift and 

volatilization risk assessments for oxyfluorfen will also be examined during the Registration 

Review process. 

There are no current aggregate risks estimates of concern for oxyfluorfen. During registration 

review, updated aggregate assessments may be conducted as required to include any significant 

change that might occur for toxicological PODs, FQPA and uncertainty factors, dietary exposure 

estimates, or estimated drinking water concentrations (EDWCs). 

The previous occupational exposure assessment3 covered all scenarios relevant to oxyfluorfen 

and no occupational handler or post-application risk estimates of concern were identified with 

use of appropriate personal protective equipment (PPE) (i.e., label required chemical-resistant 

gloves). Registration Review will include an updated handler and post application risk estimates 

based on current policies, new toxicology data (a subchronic dermal toxicity study is required), 

and required bulb vegetables Dislodgeable Foliar Residue (DFR) data. 

Chemical Use Profile 

Oxyfluorfen [2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl) benzene] is a broad 

spectrum pre- and postemergence herbicide registered for use on a variety of field crops, 

vegetables, and fruit trees and is used to control certain broadleaf and grassy weeds. 

Oxyfluorfen is a diphenyl ether herbicide structurally related to lactofen and acifluorfen. The 

diphenyl ether herbicides act by inhibiting protoporphyrinogen oxidase which is the second-tolast enzyme in chlorophyll biosynthesis in plants and in heme synthesis in animals. The diphenyl 

ethers are also oncogenic in rodents. 

Agricultural uses include control of weeds in field/row crops, orchard floors, vineyard floors, and 

container and field grown ornamentals. In the residential environment, it is used to kill weeds on 

paved surfaces such as driveways, patios and sidewalks. Major uses include grapes, almonds, 

cotton, bulb vegetables, artichokes and pasture/rangeland. Formulations include emulsifiable 

liquid products for agricultural use and granular products for commercial nursery use. 

Residential products are available as Ready to Use (RTU) trigger sprayer, RTU sprinkler jug or 

as a liquid to be applied in a sprinkler can or hand-carried tank sprayer. The application rates for 

the oxyfluorfen products range from 0.25 to 2.0 lbs ai per acre per application and one or two 

applications are typically made in the growing season. Liquid formulations might be applied 

using groundboom, airblast, chemigation, aerial and handheld sprayers. Aerial application is 

2 Oxyfluorfen: Second Revised Occupational and Residential Non-Cancer and Cancer Exposure and Risk 

Assessments for the Reregistration Eligibility Decision (RED) Document. T. Dole. 05/01 /2002. 0281831 3 Available: http://www.epa.gov/pesticides/science/residential-exposure-sop.html 

Page 3 of20 
Oxytluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

used only for fallow fields and chemigation is used primarily for bulb vegetables. Granular 

oxyfluorfen is applied to ornamentals with broadcast spreaders. 

The nomenclature and physiochemical properties of oxyfluorfen are presented in Tables 1 and 2 

of Attachment 1. 

Hazard Identificationffoxicology 

The toxicity database for oxyfluorfen is adequate to support existing registrations and registration 

review with the exception of acute and subchronic neurotoxicity studies, a subchronic dermal 

toxicity study, and an inhalation toxicity study that was waived (0282729). The Hazard and 

Science Policy Council (HASPOC) concluded that the acute and subchronic neurotoxicity 

studies are not required, however; the subchronic dermal toxicity study in rabbit is required 

(TXR # 0057003). A 1 Ox database uncertainty factor is retained for the dermal route until the 

dermal study is submitted and evaluated for risk assessment. 

Oxyfluorfen is of low acute toxicity for acute oral, dermal, and inhalation toxicity (toxicity 

category IV). It is a slight eye and dermal irritant and is not a dermal sensitizer. Oxyfluorfen was 

rapidly absorbed orally, extensively metabolized, and rapidly eliminated. Most of the compound 

was eliminated in the feces; females eliminated more in the urine than did males. A dermal 

absorption factor of 18% was selected from a rat dermal absorption study. 

The liver is the target organ for oxyfluorfen, which is observed as increased liver weight, 

histopathology, and increased liver enzymes throughout the database in all species and studies 

regardless of the duration or route of exposure. Other toxicological effects include: decreased 

body weights, increased urine production and water consumption, slight anemia, changes in 

hematological parameters and clinical chemistries, increases in kidney weights, and 

histopathological observations. Mortality was seen at the highest dose tested in oral subchronic 

studies. Based upon the developmental and reproductive toxicity studies review~d, there does not 

appear to be any increased susceptibility in animals due to pre- or postnatal exposure to 

oxyfluorfen. 

The 1 Ox Food Quality Protection Act (FQPA) Safety Factor (SF) for the protection of infants and· 

children has been reduced to 1 x for the following reasons: ( l) there is no indication of 

quantitative or qualitative increased susceptibility of rats or rabbits to in utero and/or postnatal 

exposure; (2) a developmental neurotoxicity study (DNT) with oxyfluorfen is not required; and 

(3) the dietary (food and drinking water) and non-dietary (residential) exposure assessments will 

not underestimate the potential exposures for infants and children. 

Oxyfluorfen is classified as "Likely to be Carcinogenic to Humans" based on the occurrence of 

treatment-related hepatocellular tumors in male mice and the lack of an adequate carcinogenicity 

study in a second species. Although there were no mutagenic concerns for oxyfluorfen, the data 

were inadequate to support a non-mutagenic mode of action for liver tumorigenesis. The Cancer 

Peer Review Committee recommended retaining a linear, low dose extrapolation for human risk 

assessments with a Q1* of7.32 x 10-2 (mg/kg/day)"1 in human equivalents. 

Page 4 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

The acute, subchronic, and chronic toxicity profile tables for oxyfluorfen are included in 

Attachment 2. Toxicity endpoints, points of departure (PODs), and uncertainty/safety factors 

(UF/SFs) were selected for oral, dermal, and inhalation exposure pathways for the Human Health 

Risk Assessment conducted in 2002 (D281831 ), and these are shown in Attachment 3. 

Upon review of the toxicology data and consideration of all available data including the open 

literature, the endpoints for risk assessment and all uncertainty factors may be re-evaluated 

during registration review to reflect current HED policies. 

Conclusions: The toxicity database for oxyfluorfen is adequate for assessing potential 

carcinogenetic, mutagenic, developmental, neurotoxic, imrnunotoxic, and reproductive effects. 

However, a subchronic dermal rabbit toxicity study is required. During registration review, the 

endpoints and safety factors for risk assessment may be updated to reflect current policies. 

Dietary Exposure and Risk Assessment 

The qualitative nature of the residue of oxyfluorfen in plants and livestock is adequately 

understood. The oxyfluorfen risk assessment team has determined that oxyfluorfen is the residue 

of concern for tolerance expression and/or risk assessment in crops, livestock and drinking water. 

Adequate analytical enforcement methods are available. Banana and cotton gin byproducts field 

trial data (GLN 860.1500) were submitted in response to the RED. These data will be evaluated 

during Registration Review and a tolerance for residues of oxyfluorfen inion cotton gin 

byproducts may be established. Cacao bean field trial data (GLN 860.1500) were also required 

in the RED; however, HED has re-evaluated the residue chemistry database for oxyfluorfen and 

will translate available coffee field trial data to support the existing uses of oxyfluorfen on cacao 

beans (D423251 ). 

The last dietary risk assessment for oxyfluorfen was conducted for the RED (J. Morales, 

D275401, July 12, 2001). Chronic dietary exposure was assessed for uses existing at that time, 

as well as two IR-4 petitions (grass grown for seed and strawberries). The dietary risk 

assessment was conducted using the Dietary Exposure Evaluation Model (DEEMTM, Version 

7.73). 

Anticipated residues were used in the analysis and calculated using either Pesticide Data 

Program (PDP) monitoring data or field trial data. Both the PDP and field trial data sets were 

consistent in that they show essentially all non-detectable residues, with the same limit of 

detection (0.0 1 ppm). In addition, estimates of percent crop treated (% CT) was incorporated 

into the analysis. The cancer dietary exposure/risk assessment used the following Qt* = 7.32 x 

to-2 (mglkgldayy1• 

An acute dietary risk assessment was not conducted because no appropriate endpoint attributable 

to a single dose was found, and no acute reference dose was established. Chronic dietary (food 

only) risk estimates for oxyfluorfen were below HED' s level of concern ( < 100% cP AD) for the 

U.S. population and all population subgroups based mainly on non-detects from PDP monitoring 

data and field trials (<1% cPAD for all sub-population). For the cancer dietary (food only) 

exposure assessment, the risk estimate for the US population was 3.8 x 10-7

. 

Page 5 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Water was incorporated into the dietary exposure assessment using drinking water levels of 

concern (DWLOCs). Comparisons were made between DWLOCs and the estimated 

concentrations of oxyfluorfen in surface water and ground water generated via Pesticide Root 

Zone Model/Exposure Analysis Modeling System (PRZM/EXAMS) and Screening 

Concentration In GROund Water (SCI-GROW), respectively. The dietary exposure including 

water as DWLOCs was not of concern for chronic exposure. Upon comparison of the cancer 

DWLOC with the environmental concentrations of oxyfluorfen estimated using conservative 

modeling, the surface water concentration (5.7 ppb) is greater than the cancer DWLOC (0.315 

ppb ). Thus, there may be a concern for oxyfluorfen residues in surface water. 

Conclusions: The residue chemistry database is adequate. Data submitted since the RED will 

need to be evaluated and a tolerance for residues of oxyfluorfen inion cotton gin byproducts may 

be established. Updated dietary exposure assessments may be necessary under registration 

review if there are significant changes to the drinking water estimated concentrations which will 

be updated by EFED, or if there are significant changes to the PODs or UFs/SFs. 

Residential Exposure 

The last oxyfluorfen human health risk assessment4 on residential settings (i.e., homeowners 

treating weeds on patios, driveways and similar surfaces) was done in 2002 (D28183 1, F. Fort, 

4/29/02). Short-term non-cancer risk estimates via the dermal and inhalation routes of exposure 

were assessed for residential handlers and resulting MOEs did not fall below RED's LOC of 

100, and therefore not of concern. Cancer estimates ranged from 4x 1 o8 to 6x 1 o-7. Postapplication residential exposure risks from treated turf were not quantified since labeled 

application instructions were limited to spot treatments (i.e., did not include broadcast 

application to lawns) that were intended to eliminate grass. 

Residential bystander exposures resulting from off-site transport (e.g., spray drift or 

volatilization) may occur as a result of applications of oxyfluorfen. The potential for spray drift 

will be quantitatively evaluated for each pesticide during the Registration Review process which 

ensures that all uses for that pesticide will be considered concurrently. The approach is outlined 

in the revised (2012) Standard Operating Procedures for Residential Risk Assessment (SOPs) -

Residential Exposure Assessment Standard Operating Procedures Addenda 1: Consideration of 

Spray Drift. This document outlines the quantification of indirect non-occupational exposure to 

drift. In terms of volatilization, the agency has developed a Volatilization Screening Tool and a 

subsequent Volatilization Screening Analysis 

(http://www.regulations.gov/#!docketDetail;D=EPA-HQ-OPP-2014-0219). During Registration 

Review, the agency will utilize this analysis to determine if data (i.e., flux studies, route-specific 

inhalation toxicological studies) or further analysis is required for oxyfluorfen. 

Conclusions: The residential exposure risk assessment did not identify risks of concern in 2002. 

However, updates to HED's Residential SOPs5 (2012) have been made along with policy 

changes for body weight assumptions. Therefore, the residential exposure risk assessment will 

be updated to reflect current policies during Registration Review. Additionally, a subchronic 

4 Oxyfluorfen. Revised Human Health Risk Assessment. HED Chapter for the Reregistration Eligibility Decision 

(RED), 0281831, F. Fort, 4/29/02 5 Available: http://www.epa.gov/pesticides/science/residential-exposure-sop.html 

Page 6 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

dermal rabbit toxicity study is required, therefore dermal risk estimates will need to be updated 

during Registration Review based on this study. The need for spray drift and volatilization risk 

assessment for oxyfluorfen will be examined during the Registration Review process as well. 

Aggregate Risk Assessment 

In accordance with the Food Quality Protection Act (FQPA), HED must consider and aggregate 

pesticide exposures and risks from three major sources: food, drinking water, and residential 

exposures. The aggregate risk assessment evaluates the combined risk from dietary exposure 

(food and water) and any non-occupational (residential) uses. 

Acute Aggregate 

An acute endpoint has not been identified; therefore, an acute aggregate risk assessment is not 

required. 

Short-term Aggregate 

Short-term DWLOCs were calculated based upon average food residues and residential handler 

exposure. Surface and ground water concentrations estimates using conservative modeling were 

below the short-term DWLOCs for oxyfluorfen. Consequently, there was no short-term 

exposure concern for drinking water from surface or groundwater sources. 

Chronic Aggregate 

Since no chronic residential scenarios have been identified, chronic DWLOCs for oxyfluorfen 

were calculated based on anticipated residues in food alone. Surface and groundwater 

concentrations are substantially less than the DWLOCs for all populations. Consequently, there 

is no chronic aggregate concern for drinking water from surface or groundwater sources. 

Cancer Aggregate 

Cancer DWLOCs were calculated using food only and residential exposure data. The chronic 

food cancer risk estimate was 3.8 x 10'7

, combined with the highest residential cancer risk 

estimate of 8.7 x 10·7 resulted in a food+ residential cancer risk of 1.3 x 10·6. Since USDA 

Pesticide Data Program (PDP) monitoring study and field trial data showed all residues on food 

were non-detects, the food risk estimate was considered upper-bound. Screening-level surface 

water modeling indicated that there may be a concern for oxyfluorfen in drinking water, but this 

water modeling was also considered upper-bound. Drinking water monitoring data would allow 

refinement of the Estimated Drinking Water Concentrations (EDWCs). 

Conclusions: In 2002 there were no chronic or short-term aggregate (food, water and residential 

exposure) risk estimates of concern for oxyfluorfen. However, there appears to be a potential for 

oxyfluorfen residues in drinking water to occur at levels of concern for cancer. During 

Registration Review, updated aggregate assessments will be conducted as required to include 

any significant changes that might occur for toxicological PODs, FQP A and uncertainty factors, 

dietary exposure estimates, EDWCs, and residential exposure estimates. Emerging policies 

related to pesticide drift and volatilization assessments may dictate further changes to the 

existing aggregate risk assessment. 

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Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Occupational Exposure 

Oxyfluorfen is registered as an herbicide for agricultural uses to control weeds in field/row 

crops, orchard floors, vineyard floors, and container and field grown ornamentals. Formulations 

include emulsifiable liquid products for agricultural use and granular products for commercial 

nursery use. The last comprehensive occupational risk assessment was done in 2002 for the 

RED (Tim Dole, D281831, May 2002). There is potential for occupational handler and postapplication exposure. 

Occupational Handlers 

The application rates for the oxyfluorfen products range from 0.25 to 2.0 lbs ai per acre per 

application. Liquid formulations might be applied using groundboom, airblast, chemigation, 

aerial and handheld sprayers. Aerial application is used only for fallow fields and chemigation is 

used primarily for bulb vegetables. Granular oxyfluorfen is applied to ornamentals with 

broadcast spreaders. Based on the handler activity use pattern the duration of exposure was 

determined to be of short (1 day to 30 days) and intermediate-term (1 to 6 months). Chronic 

exposure(> 6 months) is not expected since typically only one or two applications are made in 

the growing season. Registered labels require handlers to wear baseline Personal Protective 

Equipment (PPE) (i.e., long pants, long-sleeved shirt, and shoes with socks) and chemical 

resistant gloves. 

The RED addressed all occupational non-cancer handler scenarios. For occupational handlers, 

combined MOEs (dermal + inhalation) above 100 for short-term and 300 for intermediate-term 

durations do not exceed HED's level of concern. All short- and intermediate-term combined 

dermal and inhalation occupational exposure risk estimates for granular and liquid formulations 

did not exceed HED's level of concern at label required single layer PPE level (i.e., baseline PPE 

+ chemical resistant gloves). 

For the 2002 RED, an assessment was conducted for the carcinogenic risk estimates associated 

with oxyfluorfen following exposures to occupational handlers (private and commercial; mixers, 

loaders and applicators). Commercial handlers cancer risk estimates were less than 1x10"5 with 

label required PPE (i.e, baseline + gloves) and/or engineering controls. Private growers' cancer 

risk estimates were less than 1 x 1 o-6 at the same aforementioned level of PPE. 

Occupational Post-application Exposure 

For the 2002 RED, post-application non-cancer and cancer oxyfluorfen agricultural exposure 

potential risks were assessed for workers entering fields recently treated with oxyfluorfen to 

conduct tasks such as hand weeding and harvesting, shaping, scouting, irrigation, 

grading/tagging and thinning. The restricted entry interval (REI) for oxyfluorfen is currently set 

at 24 hours for all crops except for onions, garlic and horseradish which is 48 hours. Conifer 

seedlings and conifer trees were 3 and 6 days, respectively, but in 2013 an REI amendment 

request was granted to reduce these to 24 hours (D4077 51, I. Nieves, April 2013 ). 

Oxyfluorfen is a non-selective herbicide that can cause leaf damage to most of the labeled crops. 

With the exception of bulb vegetables and conifers, which have more tolerance to oxyfluorfen, 

over the top applications are not recommended. Therefore, it was determined that significant 

post-application exposure is only anticipated following applications of oxyfluorfen to conifer 

Page 8 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

seedlings, conifer trees and bulb vegetables (0281831, Tim Dole, May 2002). The registrant had 

submitted a chemical specific Oislodgeable Foliar Residue (DFR) study on conifers (MRID 

420983-01). However, the study was found to have significant deficiencies (i.e., lack of 

validation data, high fortification levels, and low recovery during the study) and new DFR data 

on conifers was requested by the Agency. 

In 2012, an oxyfluorfen DFR study on conifers was submitted by Dow AgroSciences (MRID# 

48895001) and found to be adequate for use in risk assessments (0405224, I. Nieves, February 

2013), therefore no additional OFR data are necessary for conifers. However, the Agency does 

not consider appropriate to use this chemical-specific data on bulb vegetables because of the 

significant structural difference in foliage between both crops. Based on this particularity, 

default assumptions were implemented to calculate workers' re-entry exposure risk estimates for 

bulb vegetables. Margins of exposure for the hand weeding activity (highest exposure scenario) 

did not reach the current level of concern of 3000 after 30 days after treatment (MOE= 1800). 

Therefore, since the highest estimated occupational post-application exposure using default DFR 

values is not minimal in comparison to the level of concern, EPA is requiring the 40CFR DFR 

data for bulb vegetables. 

Based on the Agency's current practices, a quantitative post-application inhalation exposure 

assessment was not performed for oxyfluorfen at this time primarily because of the low acute 

inhalation toxicity (Toxicity Category IV), and low vapor pressure of oxyfluorfen (2x 1 o-7 torr at 

20°C). However, there are multiple potential sources of post-application inhalation exposure to 

individuals performing post-application activities in previously treated fields. These potential 

sources include volatilization of pesticides and resuspension 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. The 

Agency is in the process of evaluating the SAP report as well as available post-application 

inhalation exposure data generated by the ARTF and may, as appropriate, develop policies and 

procedures, to identify the need for and, subsequently, the way to incorporate occupational postapplication inhalation exposure into the Agency's risk assessments. 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 oxyfluorfen. 

Conclusions: Previous occupational handler and post-application exposure assessments did not 

identify risks of concern when PPE was considered (i.e., label required chemical-resistant 

gloves). Registration Review will include an updated handler and post application risk estimates 

based on current policies and new toxicology data (a subchronic dermal toxicity study is 

required), and required bulb vegetables DFR data. 

Public Health and Pesticide Epidemiology Data 

HED has evaluated the available incident data6 and concludes that there does not appear to be a 

concern at this time that would warrant further investigation, since there was. a low frequency of 

incidents involving oxyfluorfen reported to the OPP Incident Data System (IDS) and the Centers 

6 Oxyfluorfen: Tier I Review of Human Incidents. E. Evans & Shanna Recore. July 17, 2014. 0419420 

Page 9 of20 
Oxy fluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

for Disease Control and Prevention/National Institute for Occupational Safety and Health 

(CDC/NIOSH) Sentinel Event Notification System for Occupational Risk (SENSOR)-Pesticides. 

The Agency will continue to monitor the incident information and if a concern is triggered, 

additional analysis will be included in the risk assessment. However; due to the large proportion 

of Ortho Fence & Grass Edger Formula II (Registration No. 239-2516) incidents, the Agency 

may evaluate this product further during the Preliminary Risk Assessment. The Agency will 

continue to monitor the incident information and if a concern is triggered, additional analysis 

will be included in the risk assessment. 

Tolerance Assessment and International Harmonization 

U.S. permanent tolerances for residues of oxyfluorfen are established under 40 CFR § 180.381 

inion a number of crop and livestock raw agricultural commodities. The tolerance expression 

will need to be updated to reflect HED's Interim Guidance on Tolerance Expressions (5/27/09, S. 

Knizner). No maximum residue limits (MRLs) for residues of oxyfluorfen have been established 

by Codex or Mexico. Excluding Canadian MRLs with no U.S. equivalent, the remaining 

Canadian MRLs are fully harmonized with U.S. tolerances. See Attachment 4. 

Cumulative Risk Assessment 

Unlike other pesticides for which EPA has followed a cumulative risk approach based on a 

common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as 

to oxyfluorfen and any other substances and oxyfluorfen does not appear to produce a toxic 

metabolite produced by other substances. For the purposes of this tolerance action, therefore, 

EPA has not assumed that oxyfluorfen 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 common mechanism on EPA's website at http://www.epa.gov/pesticides/cumulative/. 

Human Studies 

The October 2002 RED and April 2002 risk assessment relied in part on data from studies in 

which adult human subjects were intentionally exposed to a pesticide to determine their dermal 

and inhalation exposure. Many such studies, involving exposure to many different pesticides, 

comprise generic pesticide exposure databases such as the Pesticide Handlers Exposure Database 

(PHED), the Agricultural Reentry Task Force (ARTF) Database, and the Outdoor Residential 

Exposure Task Force (ORETF) Database. EPA has reviewed all the studies supporting these 

multi-pesticide generic exposure databases, and has found no clear and convincing evidence that 

the conduct of any of them was either fundamentally unethical or significantly deficient relative 

to the ethical standards prevailing at the time the research was conducted. All applicable 

requirements of EPA's Rule for the Protection of Human Subjects of Research ( 40 CFR Part 26) 

have been satisfied, and there is no regulatory barrier to continued reliance on these studies. 

Page 10 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Risk Assessment Updates and Data Deficiencies 

• A subchronic dermal rabbit toxicity study is required for oxyfluorfen (Guideline 

870.3200) 

• Chemical-specific DFR study on Bulb Vegetables (Guideline 875.2100) 

Page 11 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

References 

Table 1. Memoranda Relevant to Registration Review•. 

Author Barcode Date Title 

Habiba, Uma TXR 0057003 TBD Oxyfluorfen: Summary of the Hazard and Science 

Policy Council (HASPOC) Meeting of June 17,2014: 

Recommendations on the Requirement of Subchronic 

Dermal Toxicity Study, Acute and Subchronic 

Neurotoxicity Studies. 

Cropp- Oxyfluorfen. Cacao Bean Magnitude of the Residue 

D423251 08/07/2014 Data. Summary of Analytical Chemistry and Residue Kohlligian, B. Data. 

E. Evans and S. D419420 07117/2014 Oxyfluorfen: Tier I Review of Human Incidents Recore 

Nieves, I. D405224 02/ 13/2013 Oxyfluorfen: Dislodgeable Foliar Residue (DFR) Study 

on Conifers Secondary Review 

Nieves, I. D407751 04/ 11/2013 Oxyfluorfen: Response to Amend Restricted Entry 

Intervals (REis) for Conifer Seedlings and Conifer Trees 

on two End-Use Product Labels. 

LaMay, A. D312174 09/04/2009 Oxyfluorfen: Response to Waiver Request for 

Dislodgeable Foliar Residue Study on Conifers. 

Fort, F. D281831 04/29/2002 Oxyfluorfen. Revised Human Health Risk Assessment. 

HED Chapter for the Reregistration Eligibility Decision 

(RED) Document. 

Dole, T. D28183 1 05/01 /2002 Oxyfluorfen: Second Revised Occupational and 

Residential Non-Cancer and Cancer Exposure and Risk 

Assessments for the Reregistration Eligibility Decision 

(RED) Document 

Kidwell, J. TXR No. 04/20/2010 Oxyfluorfen: Second Report of the Cancer Assessment 

0055343 Review Committee 

Dole, T. and D282729 04/30/2002 Oxyfluorfen: Response to Request for Waiver of 

Farwell, K. Inhalation Toxicity Testing of Oxyfluorfen based upon 

exposure considerations 

Fort, F. 0281831 04/29/2002 Oxyfluorfen: Revised Human Health Risk Assessment. 

HED Chapter for the Reregistration Eligibility Decision 

(RED) Document 

Fort, F. D276585 08/8/2001 Oxyfluorfen. Toxicology Chapter for RED 

I. Thts table only mcludes references to final versiOns. PreviOus versiOns of these documents are available, but 

have been superseded. 

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Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Attachments: 

Attachment 1: Chemical Identity and Physicochemical Properties 

Attachment 2: Oxyfluorfen Acute, Subchronic, and Chronic Toxicity Profile 

Attachment 3: Oxyfluorfen Toxicological Doses and Endpoints 

Attachment 4: Oxyfluorfen International Residue Limits 

Attachment 1. Chemical Identity and Physicochemical Properties 

Table 1. Test Compound Nomenclature. 

Compound Chemical Structure 

Cl 

'-/ CH; I 11 I 

~ 

I 

~ FF KO~ 

Common name Oxyfluorfeo 

Empirical formula CtsHttCIFJNO 4 

IUPAC name 2 -chloro-1-(3-ethoxy-4-n itrophenoxy )-4-(trifluoromethyl)benzene 

CAS# 42874-03-3 

Table 2. Physicochemical Properties of Oxyfluorfen. 

Parameter Value Reference 

Melting ooint/range 84.5-86 ·c 

pH at 2o•c 9.35 

Density at 2o•c 1.53 g/mL 

Water solubility ( 25°C) 0.116 ppm 

Solvent solubility {mg/L at 20°C) Solvent gLL •c 

ethyl acetate 132 

acetone 134 

xylene >250 TGAI Product Chemistry Review1 

n-octanol 10.1 

n-heptane 3.8 

I ,2-dichloroethane >250 g/kg 

methanol 30 

Vapor pressure at 25°C 3.54 x I 0 -

7 torr 

Dissociation constant (pKa) Does not dissociate 

OctanoVwater partition coefficient Log(Kow) log Pow- 4.468 

UV /visible absorption spectrum See referenced memo 1 D256409, 7/ 16/99, Harold Podall. 

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Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Attachment 2. Oxyfluorfen Acute, Subchronic, and Chronic Toxicity Profile 

Acute Toxicity Profile - Oxyfluorfen 

Guideline Study Type MRID Test Results Toxicity 

No. Material Category 

44712010 96% LD50 > 5000 mg/kg IV 

870.1 100 Acute Oral 

44828903 97.1% LD50 > 5000 mglkg IV 

447 12011 96% LD50 > 2000 mg/kg III 

870.1200 Acute Dermal 

44828904 97.1% LD50 > 5000 mg/kg 

"' 

870.1300 Acute 447 12012 96% LC50 > 3.7 I mg/L IV Inhalation 

Primary Eye 447 12013 96% slight irritant IV 

870.2400 Irritation 44828906 96% negative IV 

Primary Skin 44712014 96% slight irritant IV 

870.2500 Irritation 44828905 96% negative IV 

Dermal 44712015 96% Negative --- 870.2600 Sensitization 448 14901 23% Negative 

Subchronic and Chronic Toxicity Profile 

Guideline No. I MRID (year) I Classificatipn I Results Study Type/ % a.i. Doses 

INOAEL for technical not defined 

LOAEL for technical = 1500 mg/kg!day based on decreased 

BW, increased liver wt, and microscopic hepatic hypertrophy 

in 1/4 animals in males and females 

870.3200 00071915 (1978), 92136014. NOAEL for EC formulation = 24.2 mglkg/day LOAEL for 28-day dermal Unacceptable tech: 1500 

toxicity - rabbits mg/kg/day EC: 24.2, 96.8 EC formulation = 96.2 mglkg/day based on decreased BW 

technical75% mgfkg/day solvent control: 0.4 NOAEL for solvent control not defined EC 31.7% mL/kg!day LOAEL for solvent control= 0.4 mL/kg based on decreased 

BW 

erma! toxicity occurred in all treatment groups 

erythema, dryness, edema) 

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· Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Subcbronic and Chronic Toxicity Profile 

Guideline No. I MRID (year) I Classification I Results Study Type/% a.i. Doses 

p007 1916 ( 1978), 000163582, !NOAEL < 0.13 mg!L (M: 33.2 mglkg/day; F: 34.9 

870.3465) 163584. 

ron-guideline 1- ~nacceptab e imglkglday 

onth inhalation ~. 0 (vehicle control), 0.13, 0.65 LOAEL = 0. 13 mg/L (M: 33.2 mg/kg/day; F: 34.9 

oxicity ~giL M: 33.2 and 166.1 lmg!kg/day based on increased liver wt in low-dose fema les, 

~3.5% ~glkg/day lbut not high-dose females, lung pathology. Low-dose group 

F: 34.9, 174.7 mglkg/day ~ometimes showed more toxicity than high-dose group, many 

loroblerns with this studv. 

870.3700a 4933103 (1997) 

Maternal NOAEL = I 000 mglkg/day (HDT) 

!Developmental- rats ~cceptable guide ine Maternal LOAEL > I 000 mg/kg/day (HOT) 

~ p, 375, 750, 1000 mg/kg/day !Developmental NOAEL = 1000 mglkg/day (HDT) 

!Developmental LOAEL > 1000 mglkg/day (HOT) 

Maternal NOAEL = 18 mg/kg/day 

Maternal LOAEL = 183 mglkg/day based on clinical signs 

red vaginal discharge, scant feces). 

~70.3700a 141806501 (1991) lA.t 848 mglkg/day, increase incidence of maternal mortality. 

p evelopmental - rats ~cceptab le non-guideline 

171.4% p, 18, 183, 848 mglkg/day Developmental NOAEL = 18 mglkg/day 

Developmental LOAEL = 183 mglkg/day based on increased 

early resorptions, decreased fetal BW, vessel variations, bent 

scapula, fused sternebrae, bent bones in fore- and hindlimbs 

Maternal NOAEL = 30 mglkg/day 

~aternal LOAEL = 90 mglkg/day based on abortions, 

870.3700b ~4933102 (1997) 

linical signs (loose feces, thin build), decreased FC, 

Developmental- lciecreased gravid uterine wt 

abbits ~cceptable non-guideline 

~ p, 10, 30, 90 mglkg/day !Developmental NOAEL = 30 mglkg/day Developmental 

JLOAEL = 90 mglkg/day based on increased late resorptions, 

lciecreased live fetuses/doe 

~aternal NOAEL = I 0 mg/kg/day 

Maternal LOAEL = 30 mg/kglday based on decreased BW 

870.3700b jo0094052 ( 1981), 00094051, ain and clinical signs (anorexia, red exudate). 

!Developmental - ~2 136018 , !At 90 mglkg/day, also increased maternal mortality, 

abbits 21360 19 acceptable/guideline ~bortions, hematuria, decreased motor activity 

126.9% WP jo, 0 (vehicle), 10, 30, 90 

formulation lmglkglday Developmental NOAEL = 30 mg/kg/day 

Developmental LOAEL = 90 mg/kg/day based on decreased 

itter size and increased early resorptions 

Page 15 of20 
Oxytluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Guideline No. I IMru» (year) I !Results ~tudy Type/ o/o a.i. lclassification I Doses 

!Parental NOAEL = 400 ppm (M: 31; F: 33 mg/kg/day) 

~2014901 (1991) IParentalLOAEL = 1600ppm(M: 120; F: 131 mg/kg/day) 

~cceptable guideline !based on mortality, decreased BW, and liver and kidney 

870.3800 p, 100, 400, 1600 ppm !histopathology {hepatocellular hypertrophy, renal pelvic 

jReproduction - rats M: 0, 7.8, 30.9, 120 !mineralization, etc) 

71.4% ~g/kg/day 

IF: o, 8.5, 32.8, 131.2 pffspring NOAEL = 400 ppm (M: 31; F: 33 mg/kg/day) 

imglkg/day pffspring LOAEL = 1600 ppm {M: 120; F: 131 mg/kg/day) 

!based on decreased BW/smaller litter size 

00078767 (1981 ), 92136062, 

92136016 

870.41 OOb acceptable/guideline !NOAEL = 100 ppm {M: 3.1 mg/kg/day; F: 3.0 mg/kg/day) 

Chronic toxicity dogs p, I 00, 600, 2000 ppm ILOAEL = 600 ppm {M: 18.5 mg/kg/day; F: 18.8 mglkg/day) 

71.4-73.8% M:0,3.1, 18.5, 61.0 !based on decreased BW gains, increased SAP, increased liver 

~g/kg/day ~ F: 0, 3 .0, 18.8, 60.3 

imglkg/day 

poo83445 (1978), oot35o72, 

870.4300 ~2136061 

ombined chronic unacceptable jNOAEL800/ 1600 ppm (M: 56.96 mg/kg/day; F: 

oxicity/ ~. 2, 40, 80011 600 ppm 172.57 mg/kg/day) 

carcinogenicity- rats M: o, o.t, 1.94, 56.96 ILOAEL > 80011600 ppm (M: 56.96 mg/kg/day; F: 

85.7% lnglkglday ~2.57 mg/kg/day). No toxicity, no neoplasia 

F: 0, 0.12, 2.43, 72.57 

~g/kg/day 

p0 117603 (1982, Nomura !NOAEL = 200 ppm (M: 14 mglkg/day; F: 18 

870.3100 nstitute) lmglkglday) 

90-Day oral toxicity - ~cceptable/guideline ILOAEL = l 000 ppm (M: 71 mglkg/day; F: 75 

ats p, 200, 1000, 5000 ppm lmglkg/day) based on brown livers and kidneys, 

72% IM: 14, 7 1, 361 mg/kg/day 8relative liver wt (M), 9absolute/relative thymus wt 

""': 18, 75, 396 mg/kg/day M), liver and kidney histopathology (slight) 

00 17602 (1982), 921360 12, 

142142316 jNOAEL < 200 ppm (M: 32.0 mg/kg/day; F: 44.4 870.3100 acceptable/guideline 

~0-Day oral toxicity - ~. 200, 800, 3200 ppm !mglkglday 

!mice IM: o, 32.o, t34.5, 490.5 p...OAEL # 200 ppm (M: 32.0 mglkg/day; F: 44.4 

72.5% lmglkg/day jmg/kg/day based on anemia 8 SGPT, 8 liver wt, liver 

It:-: 0, 44.4, 166.6, 520.9 !histopathology 

!mglkglday 

~0037939(1977),921360 7 INOAEL = 20 ppm (M: 3.0; F: 4.0 mg/kg/day) LOAEL = 200 jacceptable 

870.4200 P. 0 (ethanol), 2, 20,200 ppm IPpm (M: 33; F: 42 mg/kg/day) based on increased liver wt, 

!Carcinogenicity mice IM: 0, 0 (ethanol), 0.3, 3.0, 33 !increased SAP and SGPT, liver histopathology (including 

~7.5% lmglkg/day !hepatocyte necrosis) 

It:-: 0, 0 (ethanol), 0.4, 4.0, 

!combined adenomas/carcinomas increased: used to set Q1 ~2.0 mglkg/day * 

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Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

~70.7485 ~237 20 I (1992) !Rapidly absorbed, extensively metabolized, and rapidly 

Metabolism and eliminated. Most compounds eliminated in the feces; females 

pharmacokinetics ~265240 I ( 1993) eliminated more in the urine than did males. 

870.7600 42142306(1989), 92!36095 Maximal absorption= 18% at LDT when compound remaining 

Dermal penetration acceptable ~n skin is considered potentially absorbable. 

4822930 I (20 I 0) 

870.7800 Acceptable/guideline ~OAEL = 153.5 mglkg/day. 

lmmunotoxjcity 0, 7.6, 37.3, or 153.5 fLOAEL = was not observed. 

mglkg/day 

ABBREVIATIONS: M = Male, F = Female, BW = body weight, SAP = serum alkaline phosphatase enzyme, 

SGPT =serum glutamate pyruvate transaminase enzyme or ALT Hb = hemoglobin, PT = prothrombin time 

MFO = mixed function oxidase, EC = emulsifiable concentrate formulation, WP = wettable powder formulation 

LDT = lowest dose tested in study. 

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Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

A ttac h ment 3 T . OXICO OgiCa ID oses an d E n d . 1pom t s 

Exposure Scenario Dose Endpoint Study (mglkglday) 

Acute Dietary An appropriate endpoint attributed to a single dose was not identified. Therefore, an acute RID was 

not established. 

Liver toxicity occurring in dogs and mice at the Chronic dog study and 

NOAEL = 3.0 LOAEL of200 ppm in male (33.0 mglkg/day) and mouse carcinogenicity 

Chronic Dietary UF = 100 female ( 42.0 mg/kg/day) mice. 

Chronic RID = 0.03 mg/kg/day 

Q,*=7.32x 102 !Mouse carcinogenicity 

Cancer (mg/kg/day)·

1 Combined hepatocellular adenomas and carcinomas. study 

An appropriate endpoint attributed to short-term, incidental oral exposure was not available. Maternal 

effects in the developmental rabbit study were not used because decreased food consumption was not 

Incidental Oral, accompanied by decreased body weight and clinical signs in this study were believed to be pregnancy 

related, and thus not related to the population of concern (infants and children). The 90-day mouse Short-Term study selected for the intermediate-term incidental oral exposure (see below), was not used because 

hepatic toxicity in this study is not believed to occur after 1-7 days exposure and exposure by this 

short-term incidental exposure is not expected to exceed one week in duration for oxyfluorfen. 

Incidental Oral,** LOAEL = 32 Liver toxicity and anemia seen at the LOAEL of32 90-day mousec 

Intermediate-Term UF = 300 mg/kg/day. 

Dermal*, NOAEL=30 Abortions and clinical signs seen at the maternal Developmental rabbit 

Short- Terma UF = 1000 LOAEL of90 mg/kg/day study ( 1998) 

Dermal*,** LOAEL= 32 Liver toxicity and anemia seen at the LOAEL of 32 90-day mouse 

Intermediate-Term a UF = 3000 mglkg/day. 

Dermal*, NOAEL = 3.0 Liver toxicity occurring in dogs and mice seen at Chronic dog study and 

Long- Terma UF = 1000 he LOAEL of 18 mg/kglday in dogs and 33 in mice. mouse carcinogenicity 

Inhalation, NOAEL = 30 Abortions and clinical signs seen at the maternal Developmental rabbit 

Short- Termb UF = 100 LOAEL of90 mg/kg/day. study (1998) 

Inhalation,** LOAEL = 32 Liver toxicity and anemia seen at the LOAEL of 32 90-day mouse 

lntermediate-Termb UF = 300 mglkg/day. 

Inhalation, NOAEL = 3.0 Liver toxicity occurring in dogs and mice seen at the Chronic dog study and 

Long- Termb UF = 100 LOAEL of 18 mglkglday in dogs and 33 in mice. mouse carcinogenicity 

a. An oral endpomt was used for dermal exposure: dermal absorption factor of 18% of oral 

exposure shall be used. 

b. An oral endpoint was used for inhalation exposure: inhalation exposure assumed 

equivalent to oral exposure. 

c. The 90-day toxicity study in rats (98% a.i.) was considered for use as an endpoint. However, this study was not 

selected because mice were more sensitive to the old technical (71% a.i.) than rats and no subchronic mouse study 

with the 98% a .i. is available. 

NOAEL = no observed adverse effect level; LOAEL =lowest observed adverse effect level 

*HASPOC determination subchronic dermal study is required and a I OXoa uncertainty factor will be retained for all 

dermal assessments until this requirement is fulfilled. **LOAEL to NOAEL extrapolation a 3X factor is retained . 

Page 18 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Attachment 4. International Residue Limits 

Oxyfluorfen (111601; 6/23/14) 

Summary of US and International Tolerances and Maximum Residue Limits 

Residue Definition: 

us Canada Mexico1 Codex 

40 CFR 180.381 : 2-chloro-a,a,a-tritluoro-p- None 

Plant/Livestock: oxytluorfen [2-chloro-1-(3- tolyl 3-ethoxy-4-nitrophenyl 

ethoxy-4-nitrophenoxy)-4- ether 

(tritluoromethy !)benzene] 

Commodity Tolerance (ppm) !Maximum Residue Limit m~ kf!) 

us Canada Mexico1 Codex 

Almond, hulls 0.1 

Artichoke, globe 0.05 

Avocado 0.05 

Banana 0.05 

Broccoli 0.05 0.05 

Cabbage 0.05 0.05 

Cacao bean, dried bean 0.05 

Cattle, fat 0.01 

Cattle, meat 0.01 

Cattle, meat byproducts 0.01 

Cauliflower 0.05 0.05 

Coffee, bean, green 0.05 

Corn, field, grain 0.05 

Cotton, undelinted seed 0.05 

Date, dried fruit 0.05 

Egg 0.03 

Feiioa 0.05 

Fig 0.05 

Fruit, pome, group 11 0.05 

Fruit, stone, group 12 0.05 

Goat, fat 0.01 

Goat, meat 0.01 

Goat, meat byproducts 0.0 1 

Grape 0.05 

Hog, fat 0.01 

Hog, meat 0.01 

Hog, meat byproducts 0.01 

Horse, fat 0.01 

Horse, meat 0.01 

Horse, meat byproducts 0.01 

Horseradish 0.05 

Kiwifruit 0.05 

Milk 0.01 

Nut, tree, group 14 0.05 

Olive 0.05 

Onion, bulb 0.05 0.05 

Peppermint, tops 0.05 

Page 19 of20 
Oxyfluorfen: Human Health Risk Assessment Scoping Document in Support of Registration Review 

Summary of US and International Tolerances and Maximum Residue Limits 

Residue Definition: 

us Canada Mexico1 Codex 

Persimmon 0.05 

Pistachio 0.05 

Pomegranate 0.05 

Poultry, fat 0.2 

Poultry, meat 0.01 

Poultry, meat byproducts 0.01 

Sheep, fat 0.01 

Sheep, meat 0.01 

Sheep, meat byproducts 0.01 

Soybean 0.05 

Spearmint, tops 0.05 

MRLs with No US Equivalent 

Brussels sprouts 0.05 

Chinese broccoli 0.05 

Chinese mustard cabbages 0.05 

Kohlrabies 0.05 

Napa Chinese cabbages 0.05 

Strawberries 0.05 

Completed: M. Negussie; 06/25/ 14 1 Mex1co adopts US tolerances and/or Codex MRLs for 1ts export purposes. 

Tolerances with regional registrations. Tolerances with regional registration are established for 

residues of the herbicide oxyfluorfen [2-chloro-1-(3-ethoxy-4-nitrophenoxy )-4-

( tn . f1 uoromet h y l)b enzene ] . moron t h e o fi 11 owm. g fi oo d commo eli . tles: 

Commodity Parts per million Canadian MRL 

Blackberry 0.05 

Chickpea, seed 0.05 

Grass, forage 0.05 

Grass, hay 0.05 

Grass, seed screenings 0.05 

Guava 0.05 

Papaya 0.05 

Raspberry 0.05 0.05 

Taro, corm 0.05 

Taro, leaves 0.05 

Page 20 of20