EPA REGISTRATION DIVISION COMPANY NOTICE OF FILING FOR 

PESTICIDE PETITIONS PUBLISHED IN THE FEDERAL REGISTER 

EPA Registration Division contact: Joanne I. Miller 703-305-6224

INSTRUCTIONS: Please utilize this outline in preparing the pesticide petition. In 

cases where the outline element does not apply, please insert “NA-Remove” and 

maintain the outline. Please do not change the margins, font, or format in your 

pesticide petition. Simply replace the instructions that appear in green, i.e., “[insert 

company name],” with the information specific to your action.

TEMPLATE:

Syngenta Crop Protection, Inc.

[Insert petition number]

EPA has received a pesticide petition ([insert petition number]) from Syngenta 

Crop Protection, Inc., PO Box 18300, Greensboro, NC 27419-8300 proposing, 

pursuant to section 408(d) of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 

U.S.C. 346a(d), to amend 40 CFR part 180.

(Options (pick one)

by establishing a tolerance for residues of fluazifop-p-butyl in or on the raw 

agricultural commodities banana at 0.01 parts per million (ppm), plantains at 0.01 

parts per million (ppm), citrus (whole fruit) at 0.05 parts per million (ppm), 

citrus (dried pulp) at 0.40 parts per million (ppm), citrus (oil) at 0.05 parts per 

million (ppm), citrus (juice) at 0.05 parts per million (ppm), grapes at 0.01 parts 

per million (ppm), sugarbeet (root) at 0.25 parts per million (ppm), sugarbeet 

(top) at 1.5 parts per million (ppm), sugarbeet (dried pulp) at 1.0 parts per 

million (ppm), and sugarbeet (molasses) at 3.5 parts per million (ppm). EPA has 

determined that the petition contains data or information regarding the elements set 

forth in section 408 (d)(2) of FDDCA; however, EPA has not fully evaluated the 

sufficiency of the submitted data at this time or whether the data supports granting of 

the petition. Additional data may be needed before EPA rules on the petition.

A. Residue Chemistry

1. Plant metabolism. [The metabolism of fluazifop-p-butyl is adequately 

understood for the purpose of the proposed tolerances.]

2. Analytical method. [Syngenta has developed and validated analytical 
2

methodology for enforcement purposes. This method has been submitted to the 

Agency and is in PAM Vol. II, Method II. An extensive database of method 

validation data using this method on various crop commodities is available.] 

3. Magnitude of residues. [Complete residue data to support the requested 

tolerances are submitted with this petition. The requested tolerances are adequately 

supported. These studies were conducted per EPA Test Guidelines 860.1000, 

860.1500, and 860.1520.] 

B. Toxicological Profile

1. Acute toxicity. [Fluazifop-p-butyl technical and the end-use formulation 

have low acute toxicity by oral, dermal and inhalation exposure routes. For 

fluazifop-p-butyl technical, the oral LD50 in rats is 3680 mg/kg for males and 2451 

mg/kg for females. The rabbit dermal toxicity LD50 is >2000 mg/kg and the rat 

inhalation LD50 is 1.7 mg/l air. Fluazifop-p-butyl technical is mildly irritating to 

the rabbit eye and slightly irritating to rabbit skin. Fluazifop-p-butyl technical is 

not a skin sensitizer.]

2. Genotoxicty. [Fluazifop-p-butyl has been tested for its potential to induce 

gene mutation and chromosomal changes in different test systems. Fluazifop-pbutyl was negative in bacterial reverse gene mutation assays and in mouse 

lymphoma mammalian cell mutation assays. Fluazifop-p-butyl was negative in in 

vitro chromosomal aberrations assay in human blood lymphocytes and was negative 

in the in vivo mouse micronucleus test.]

3. Reproductive and developmental toxicity. [A number of developmental 

toxicity studies have been conducted. Based on an HED review of all relevant data, 

the Agency concluded that the degree of concern is low. The overall NOAEL for the 

rat studies is 2.0 mg/kg/day and the LOAEL is 5.0 mg/kg/day. For single dose 

effects, the NOAEL is 50 mg/kg/day and the LOAEL is 200 mg/day based on 

diaphragmatic hernia malformations.]

4. Subchronic toxicity. [Fluazifop-p-butyl was evaluated in a number of 

subchronic studies. In a 90-day rat oral toxicity study the NOAEL was 0.5 

mg/kg/day. Effects at higher doses included decreased spleen and testicular weight 

and decreased hematological parameters in males. Fluazifop-p-butyl was also 

evaluated in a 90-day oral toxicity study with hamsters. The NOAEL was 78.3 

mg/kg/day, based on decreased body weight and body weight gain as well as food 

efficiency in males at higher doses levels. Signs of liver toxicity and centrilobular 

eosinophilia were observed in males and females. No dermal toxicity study was 

conducted; however, the study was conducted with a similar compound, fluazifopbutyl. In a 21/28 day dermal rabbit study conducted with fluazifop-butyl, the 
3

NOAEL was 100 mg/kg/day. LOAEL was 500 mg/kg/day based on the death of a 

male.]

5. Chronic toxicity. [The Agency has classified fluazifop-p-butyl as not likely 

to be carcinogenic in humans. In a hamster carcinogenicity studythe NOAEL was 

12.5 mg/kg/day for males and 12.1 mg/kg/day for females. In a combined 

carcinogenicity/chronic toxicity study in Wistar rats, in males the LOAEL was 80 

ppm (4.15 mg/kg/day) and the NOAEL was 10 ppm (0.51 mg/kg/day). For females 

the LOAEL was 250 ppm (16.0 mg/kg/day) and the NOAEL was 80 ppm (5.2 

mg/kg/day).]

6. Animal metabolism. [The metabolism of fluazifop-p-butyl in rats is 

adequately understood.]

7. Metabolite toxicology. [The major metabolites of fluazifop-p-butyl are 

fluazifop acid (free and conjugated), 5-trifluromethyl-2-pyridone and 2-(4-

hydroxyphenoxy) propionic acid (free and conjugated). Based on their structures, 

these compounds are likely to be significantly less toxic than parent.]

8. Endocrine disruption. [There is no indication of endocrine disruption 

potential from the fluazifop-p-butyl toxicology data. There is no hormonal 

disruption or evidence of developmental or reproductive toxicity in the absence of 

maternal toxicity. Furthermore, the chemical structure of fluazifop-p-butyl

indicates that it is unlikely to disrupt mammalian hormones.]

C. Aggregate Exposure

1. Dietary exposure. Acute (Tier III) and chronic (Tier III) dietary exposure 

evaluations were made for fluazifop-p-butyl using the Dietary Exposure Evaluation

Model software with the Food Commodity Intake Database (DEEM-FCIDTM, 

version 2.16) from Exponent. All consumption data for these assessments was taken 

from the USDA’s Continuing Survey of Food Intake by individuals (CSFII) with the 

1994-96 consumption database and the Supplemental CSFII children’s survey 

(1998) consumption database. These exposure assessments included all currently 

registered uses of fluazifop-p-butyl plus uses on bananas, citrus fruits, grapes and 

sugar beets. Residue data was taken from field trials where fluazifop-p-butyl was 

applied at the maximum intended use rate and samples were harvested at the 

minimum pre-harvest interval (PHI) to obtain maximum residue values. Calculated 

and projected percent crop treated (%CT) values were incorporated in these 

assessments. Anticipated residues in meat and milk were calculated by constructing 

theoretical nutritionally balanced diets. Drinking water estimates were included 

directly into the dietary exposure assessment using the higher of the estimated 

drinking water concentrations (EDWCs) for surface and ground water.
4

i. Food. Acute Exposure. The acute assessment was only performed for the 

females (13-49 years old) subpopulation as this subpopulation was the only one for 

which an acute endpoint was determined. The acute dietary risk assessment was 

performed with an acute reference dose of 0.5 mg/kg-bw/day based on an acute no 

observed adverse effect level (NOAEL) of 50 mg/kg/day developmental toxicity 

study in rats and an uncertainly factor of 100X. The 100X safety factor includes 

intra- and interspecies variations. No additional FQPA safety factor was applied. 

The acute assessment was run using DEEM-FCIDTM software using field trail 

residues and %CT values. For the purpose of the aggregate risk assessment, the 

exposure value was expressed in terms of margin of exposure (MOE), which was 

calculated by dividing the NOAEL by the exposure for the females (13-49 years old) 

subgroup. In addition, exposure was expressed as a percent of the acute reference 

dose (% aRfD). Acute food exposure to the females (13-49 years old) subpopulation 

resulted in a MOE of 20,935 (0.5 % of the acute RfD of 0.5 mg/kg-bw/day). Since 

the Benchmark MOE for this assessment was 100 and since the EPA generally has 

no concern for exposures below 100% of the RfD, Syngenta believes that there is a 

reasonable certainty that no harm will result from acute dietary (food) exposure to 

residues arising from the current and proposed uses for fluazifop-p-butyl.

Chronic Exposure. The chronic assessment was run using DEEM-FCIDTM software 

using average field trial residue values and %CT values. The chronic dietary risk 

assessment was performed for all population subgroups with a chronic reference 

dose of 0.0074 mg/kg-bw/day based on a two-generation reproduction study in rats 

with a NOAEL of 0.74 mg/kg/day and an uncertainly factor of 100X. The 100-fold 

safety factor includes intra- and interspecies variations. No additional FQPA safety 

factor was applied. For the purpose of the aggregate risk assessment, the exposure 

values were expressed in terms of margin of exposure (MOE), which was calculated 

by dividing the NOAEL by the exposure for each population subgroup. In addition, 

exposure was expressed as a percent of the chronic reference dose (% cRfD). 

Chronic food exposure to the U.S. population resulted in a MOE of 9,035 (1.1% of 

the cRfD of 0.0074 mg/kg-bw/day). Chronic food exposure to the most exposed subpopulation (children, 1-2 years old) resulted in a MOE of 3,801 (2.6% of the cRfD of 

0.0074 mg/kg-bw/day). Since the Benchmark MOE for this assessment was 100 and 

since EPA generally has no concern for exposures below 100% of the RfD, Syngenta 

believes that there is a reasonable certainty that no harm will result from chronic 

dietary (food) exposure to residues arising from the current and proposed uses for 

fluazifop-p-butyl.

Cancer. Fluazifop-p-butyl has been classified as “not likely carcinogen to humans”. 

Therefore no dietary cancer assessment was performed.

ii. Drinking water. The Estimated Drinking Water Concentrations (EDWCs) 

of fluazifop-p-butyl (evaluated as fluazifop-p-acid) were determined using Tier l 

SCI-GROW which estimates pesticide concentration in ground water and Tier II 
5

PRZM/EXAMS which estimates pesticide concentration in surface water. EDWCs 

of fluazifop-p-acid from the currently registered uses plus the proposed uses on 

bananas, citrus, grapes, and sugar beets were determined. Based on the SCIGROW modeling, the groundwater EDWC for fluazifop-p-acid is 0.255 ppb (acute 

and chronic) based on the currently registered uses on tree fruits (apricots, cherries, 

nectarines, peaches, plums, prunes) and pecans and proposed uses on bananas, 

citrus, and grapes. Based on Tier II PRZM/EXAMS modeling for surface water, 

the proposed citrus use provided an acute EDWC of 38.807 ppb and a chronic 

EDWC of 5.566 ppb (adjusted for 0.87 Percent Cropped Area, PCA). Since the 

surface water EDWCs exceed the ground water EDWC, the surface water values 

were used for risk assessment purposes and will be considered protective for any 

ground water concentration concerns. 

Acute Exposure from Drinking Water. The acute surface water EDWC of 38.807 

ppb was input directly into the DEEM-FCIDTM software as “water, direct and 

indirect, all sources” to model the acute drinking water exposures. Exposure 

contributions at the 99.9%-ile of exposures were determined by taking the 

difference between the aggregate (food + drinking water) exposures and the food 

(alone) exposures for each population subgroup. Acute drinking water exposure to 

the females (13-49 years old) subpopulation resulted in a MOE of 15,718 (0.6% of 

the acute RfD of 0.5 mg/kg-bw/day). Since the Benchmark MOE for this assessment 

was 100 and since EPA generally has no concern for exposures below 100% of the 

acute RfD, Syngenta believes that there is a reasonable certainty that no harm will 

result from acute drinking water exposure to residues arising from the current and 

proposed uses for fluazifop-p-butyl.

Chronic Exposure from Drinking Water: The chronic surface water EDWC of 5.566 

ppb was input directly into the DEEM-FCIDTM software as “water, direct and 

indirect, all sources” to model the chronic drinking water exposures. Chronic 

drinking water exposure to the U.S. population resulted in a MOE of 6,308 (1.6% of 

the cRfD of 0.0074 mg/kg-bw/day). Chronic drinking water exposure to the most 

exposed sub-population (infants, <1 year old) resulted in a MOE of 1,924 (5.2% of 

the cRfD of 0.0074 mg/kg-bw/day). Since the Benchmark MOE for this assessment 

was 100 and since EPA generally has no concern for exposures below 100% of the 

cRfD, Syngenta believes that there is a reasonable certainty that no harm will result 

from chronic drinking water exposure to residues arising from the current and 

proposed uses for fluazifop-p-butyl.

2. Non-dietary exposure. Fluazifop-p-butyl is a selective herbicide used in the 

post-emergent control of grasses in agricultural, ornamental, residential and 

recreational (golf course) settings. A residential exposure and risk assessment was 

performed for fluazifop-p-butyl uses on turf and ornamentals using the endpoints 

and uncertainty factors established by the EPA. The fluazifop-p-butyl end-use 

products are formulated as both liquid concentrates and ready-to-use (RTU) 

liquids. Homeowners can apply the liquid formulations using a low pressure 
6

handwand (LPHW) or a hose end sprayer with either a dial type spray attachment 

(DTS) or a sprinkler attachment. Homeowners can apply the RTU liquids using a 

hose end sprayer with a sprinkler attachment or a trigger-pump sprayer The 

homeowner handler and residential post-application exposure and risks were 

determined based on the highest use rates for all lawn and garden products that 

contain fluazifop-p-butyl. Based on the labels for the various products containing 

fluazifop-p-butyl, there is a potential for residential handler exposure from 

consumers making applications to home lawns and ornamentals. There is also a 

potential for post-application residential exposure to adults and children re-entering 

treated lawns and to adults and youths playing golf on treated turf. The following 

endpoints were used in these residential risk assessments: NOAEL = 100 mg/kg/day 

(short-term incidental oral endpoint from a developmental toxicity study in rats) 

and NOAEL = 2 mg/kg/day (short-term dermal endpoint from a developmental 

toxicity study in rats), and NOAEL = 2 mg/kg/day (short-term inhalation endpoint 

from a developmental toxicity study in rats). The resultant combined short-term 

MOEs were 238 (adult handler risk for hose-end-dial type sprayer) and 240 

(combined total post-application risk for children 1-6 years old). Both children (1-6 

years old) and adults (20-49 years old) MOEs are above the benchmark MOE of 100 

and thus do not exceed the EPA’s level of concern.

D. Cumulative Effects

Cumulative Exposure to Substances with a Common Mechanism of Toxicity. 

Section 408(b)(2)(D)(v) requires that, when considering whether to establish, 

modify, or revoke a tolerance, the Agency consider “available information” 

concerning the cumulative effects of a particular pesticide’s residues and “other 

substances that have a common mechanism of toxicity”. The EPA does not have, at 

this time, available data to determine whether fluazifop-p-butyl has a common 

mechanism of toxicity with other substances or how to include this pesticide in a 

cumulative risk assessment. For the purposes of this tolerance action, the EPA has 

not assumed that fluazifop-p-butyl has a common mechanism of toxicity with other 

substances.

E. Safety Determination

1. U.S. population. Using the conservative assumptions described above, and 

based on the completeness and reliability of the toxicity data, the acute aggregate 

exposure calculation for current and proposed uses of fluazifop-p-butyl provided a 

MOE of 8,978 (1.1% of the aRfD of 0.5 mg/kg-bw/day) for the females (13-49 years 

old) subpopulation. The acute assessment was only performed for the females (13-

49 years old) subpopulation as this subpopulation was the only one for which an 

acute endpoint was determined. The chronic aggregate exposure calculation for 

current and proposed uses of fluazifop-p-butyl provided a MOE of 3,719 (2.7% of 

the cRfD of 0.0074 mg/kg-bw/day) for the U.S. population. Since the aggregate 

MOEs exceed the Benchmark MOE of 100, Syngenta believes that there is a 
7

reasonable certainty that no harm will occur to the U.S. Population and the females 

(13-49 years old) subpopulation from acute or chronic aggregate exposures arising 

from the current and proposed uses for fluazifop-p-butyl.

2. Infants and children. No acute aggregate exposure calculation was 

performed for the infants and children subgroups for the acute assessment, since no 

acute endpoint was determined for these subgroups. Using the conservative 

assumptions described in the exposure section above, and based on the completeness 

and reliability of the toxicity data, the chronic aggregate exposure calculation for 

current and proposed uses of fluazifop-p-butyl provided a MOE of 1,648 (6.1% of 

the cRfD of 0.0074 mg/kg-bw/day) for the infants < 1 year old (the most sensitive 

population subgroup for the chronic assessment). Since the aggregate MOEs exceed 

the Benchmark MOE of 100, Syngenta believes that there is a reasonable certainty 

that no harm will occur to infants and children from the chronic aggregate 

exposures arising from the current and proposed uses for fluazifop-p-butyl.

F. International Tolerances

There are currently no Maximum Residue Limits (MRLs) set for fluazifop-pbutyl for crops by the Codex Alimentarius Commission. International MRLs for 

the herbicide fluazifop-p-butyl have been established for various agricultural 

commodities in a number of countries including Czech Republic, Denmark, 

Luxembourg, Netherlands, and Sweden.