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Fluazifop-butyl. TOXNET profile from Hazardous Substances Data Bank.


See for Updates: http://toxnet.nlm.nih.gov/cgi-bin/sis/search

FLUAZIFOP-BUTYL
CASRN: 69806-50-4
For other data, click on the Table of Contents

Human Health Effects:

Emergency Medical Treatment:

Animal Toxicity Studies:

Non-Human Toxicity Excerpts:

Very low toxicity to bees, both orally and by contact.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

Low toxicity to aquatic invertebrates.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

Mild skin and eye irritant; practically non-irritating to eyes (rabbits). Not a skin sensitizer (guinea pigs).
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**


Non-Human Toxicity Values:

LD50 Rat male oral >2,000 mg/kg, female rat 3,600 mg/kg
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LD50 male Mouse male oral 1,490 mg/kg, female mouse 1,770 mg/kg
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LD50 Guinea pig male oral 2,659 mg/kg
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LD50 Rabbit oral 621 mg/kg
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LD50 Rat percutaneous >6,050 mg/kg
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LD50 Rabbit percutaneous >2,420 mg/kg
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LC50 Rat inhalation >5.24 mg/L/4 hr
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LD50 Rat ip 1,761 mg/kg
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

NOEL Dog 5 mg/kg daily /1 yr feeding trial/
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

NOEL Rat 100 mg/kg diet /90-day feeding trial/
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

NOEL Mouse 5 mg/kg diet /2-yr feeding trial/
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LD50 Rat oral 3,328 mg/kg
[Farm Chemicals Handbook 1997. Willoughby, OH: Meister Publishing Co., 1997.,p. C170]**PEER REVIEWED**


Ecotoxicity Values:

LD50 Mallard duck oral >17,000 mg/kg
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LC50 Mallard duck >25,000 mg/kg diet/5-Day dietary/
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LC50 Ring-necked pheasants >18,500 mg/kg diet /5-Day dietary/
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LC50 Rainbow trout 1.37 mg/L/96 hr /conditions of bioassay not specified/
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LC50 Mirror carp 1.31 mg/L/96 hr /conditions of bioassay not specified/
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**

LC50 Bluegill sunfish 0.53 mg/L/96 hr /conditions of bioassay not specified/
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**


TSCA Test Submissions:

Fluazifop-butyl (CAS # 69806-50-4) was evaluated for subchronic oral toxicity in beagle dogs (4/sex/group) administered doses of 0 (vehicle control, corn oil), 5, 25 and 250 mg/kg/day in gelatin capsules for 13 weeks. Severe corneal ulceration, requiring humane sacrifice of 2 males and 1 female of a 250 mg/kg/day dosage during Week 4, prompted adjustment of this regimen to 125 mg/kg/day for the remainder of study. Prior to sacrifice, these dogs also exhibited progressive conjunctivitis and photophobia, and all lost weight. Hematology revealed reduced platelet counts, neutrophilia and immature white cells. Bilirubin, and alanine amine-transferase and alkaline phosphatase activity were elevated, and plasma protein concentrations were slightly depressed. The urine contained bile pigments and appeared bright yellow. Distended gall bladders, large friable livers and congested caecum and colon from engorgement of the blood vessels were noted upon necropsy. Histopathological evaluation confirmed treatment-related lesions of the eyes, liver, testes and gastrointestinal tract. Conversely, all dogs surviving 13-week treatment showed no clinical signs of toxicity, and no treatment-related changes on physical and ophthalmic examinations at Weeks 4, 8 and 12. All observed abnormalities were noted solely in the high-dose treatment group, including reduced food intake and bodyweight gains were most pronounced from Weeks 4-8 and reduced platelet counts, as seen in the early sacrificed animals, were resolved upon reduction of the dosage. Alkaline phosphatase, alanine amino-transferase and aspartate amino-transferase activities were increased in 250 mg/kg/day males just prior to the adjustment to a 125 mg/kg/day dosage, while both high-dose females and males exhibited alanine amino-transferase activity throughout 13-week treatment. High-dose dogs also had increased bromosulphonphthalein retention at the end of treatment, while glucose and cholesterol were slightly reduced throughout study. Upon terminal necropsy, organ weights and gross pathology of dogs surviving 13-week study were unremarkable and histopathological analysis identified a solitary incidence of arrested maturation in the testicular germinal epithelium of one high-dose male.
[ICI AMERS INC; Butyl 2-(4-(5-trifluoromethyl-2-pyridyloxy)phenoxy) propionate: 13-Week Oral Toxicity Study in Beagle Dogs; 04/24/80; EPA Doc No. 88-920006846; Fiche No. OTS0543851] **UNREVIEWED**

Fluazifop-butyl (CAS # 69806-50-4) was evaluated for subchronic dietary toxicity in Wistar rats (20/sex/group) receiving 0, 10, 100 and 2000 ppm by dietary inclusion for 13 weeks. Mean achieved dosages during 13-week treatment were 0, 0.7, 7.1 and 144.5 mg/kg/day in males of the respective treatment groups and 0, 0.8, 8.0 and 161.9 mg/kg/day in females. No mortality or pharmacotoxic signs were documented throughout treatment at any exposure level. In males of a 2000 ppm dietary exposure, treatment was associated with depressed food intake and bodyweight gains. Less efficient food utilization was noted in the high-dose males relative to controls. High-dose males also exhibited abnormalities in hematological values (Weeks 5 and 11), including slightly depressed packed cell volume, hemoglobin concentration and red blood cell count. The serum chemistry in this group was characterized by elevated alkaline phosphatase values, and higher alanine amino-transferase and aspartate amino-transferase activities. Also, cholesterol and total protein concentrations were low as compared to controls. The plasma of 2000 ppm females was found at Week 11 with depressed total protein and albumin contents relative to controls. Again at Week 11, isolated instances of elevated urinary protein levels were identified among high-dose males and females. Upon terminal necropsy, only high-dose males had evidence of hepatic enlargement or swelling (7/20), although higher absolute and relative liver weights were significant (p < 0.01, Student's t-test) in both males and females of the 2000 ppm group. Also, relative kidney weights were also significantly elevated in the high-dose males. Histopathology confirmed a specific liver toxicity in male rats, marked by significant dose-related hepatocytic hypertrophy with isolated instances of vesicular nuclei and or periacinal hepatocytic necrosis. Renal tubular degeneration, 70% and 20% in 2000 and 100 ppm males respectively, correlated with elevated kidney weights in these groups.
[ICI AMERICAS INC; 13 Week Dietary Toxicity Study with PP009 in Rats (Final Report); 05/29/80; EPA Doc No. 88-920006943; Fiche No. OTS0545346] **UNREVIEWED**

Fluazifop-butyl (CAS # 69806-50-4) was evaluated for subacute oral toxicity in Wistar albino rats (10/sex/group) administered 10 ml/kg doses in corn oil of 0, 4, 20, 100 and 500 mg/kg/day by oral gavage, 5 days/week for 2 weeks. Five-day weekly treatment periods were each followed by 2-day recovery. High-dose males only displayed overt toxicity and comprised the 2 study lethalities. These two 500 mg/kg/day males were sacrificed in extremis on Days 11 and 14 with severe pharmacotoxic signs including piloerection, reduced motor activity, retinal pallor, and a prone or hunched posture. One rat was bleeding from the penis. High-dose males consumed less food than control rats and their growth rate was depressed from Day 10, although mean bodyweights by the end of study were not significantly lower than controls. Hematology and serum chemistries suggested a primary toxicity of the liver, mostly in high-dose males. Males of the 500 mg/kg/day dosage group were found with statistically significant deficiencies in group mean hemoglobin concentration, packed cell volume, mean cell volume and erythrocyte count. Also, neutrophil counts were elevated and activated thromboplastin times were also increased in a dose-related manner. Blood chemistry indicated a dose-related elevation of alkaline phosphatase activity in 100 and 500 mg/kg/day males, elevated aspartate amino-transferase activity in 500 mg/kg/day males, and elevated cholesterol concentrations in 500 mg/kg/day males and females. Conversely, enzyme activity was depressed in rats of lower dosages. Blood samples from 1 rat killed in extremis showed still greater stimulation of enzyme activity, with reduced plasma proteins and electrolyte imbalance. Bone marrow cytology was negative for any treatment-related changes. Upon gross necropsy, no gross lesions related to treatment were identified. The decedent animals were found with abnormal upper gastrointestinal contents, and one rat exhibited congestion of mesenteric lymph nodes with pallor of kidneys, liver and spleen. Male rats of 100 and 500 mg/kg/day dosages had higher absolute and relative liver weights that was not seen in their female counterparts. Microscopic examination confirmed a particular liver pathology of treated males, characterized by dosage-related hepatocytic hypertrophy and necrosis (study lethalities), and dosage-related slight to moderate periacinal hepatocytic hypertrophy. Females of the 2 highest dosage groups only demonstrated dosage-related, slight increases in periacinal hypertrophy. Micropathological changes also included decreased periacinal hepatocytic anoxic vacuolation in all males but those of the highest dosage group and a universal treatment-related extramedullary hemopoiesis.
[ICI AMERS INC; 14 Day Subacute Oral Toxicity Study with PP009 in Rats; 07/11/80; EPA Doc No. 88-920007017; Fiche No. OTS0545392] **UNREVIEWED**

Fluazifop butyl (CAS # 69806-50-4) was evaluated for developmental toxicity in the progeny of Sprague-Dawley CD rats administered oral doses of 0 (corn oil vehicle control), 10, 50 and 200 mg/kg/day by gavage on gestation days 6-20. The general condition of treated rats was comparable to controls. Treatment did not alter food consumption and usage efficiency, although terminal mean bodyweights were significantly (p < 0.05; multiple t-test) depressed in the high-dose (200 mg/kg/day) group. Gravid uterus weights were also significantly (p < 0.01) elevated in association with the high dosage. Relative liver weights were also significantly (p < 0.05) greater in high-dose dams. Upon necropsy, no in-utero fetal mortality was attributable to treatment. Delayed fetal ossification and reduced fetal weight were dose-related and evident at all treatment levels, although fetal weights in association with dosages of 10 and 50 mg/kg/day were within the threshold of historical controls. Observed low incidence diaphragmatic hernia in fetuses of treated animals was also presumed a toxic response, although an unequivocal dose-response relationship was not established.
[ICI AMERS INC; Butyl 2-(4-(5-trifluoromethyl-2-pyridyloxy)phenoxy) propionate butyl: Effects of Oral Administration Upon Pregnancy in Rats; 05/23/80; EPA Doc No. 88-920006839; Fiche No. OTS0543844] **UNREVIEWED**

Fluazifop butyl was evaluated for reproductive and developmental effects in 2 successive generations of Charles River Wistar strain rats (30/sex/group) exposed continuously to 0, 10, 80 and 250 ppm in the diet. Each respective parent generation had received treatment for a minimum of 100 days (F0) and 120 days (F1) prior to mating. F0 and F1 dams weaned their progeny for 25 days postpartum to time of offspring selection for mating and continued study (F1) or sacrifice (F1, F2). Thirty days after sacrifice of their offspring, the surviving F1 females and select F1 males were sacrificed and with representative F1 and F2 offspring were examined histologically. The reproductive organs of remaining F0 and F1 males were likewise investigated for micropathological signs of toxicity. Treatment in the F0 generation could not be credited with any mortality or clinical toxicity, despite confirmation of effective serial dosing by metabolite determinations in the urine of treated animals. While males of all F1 treatment groups also showed no evident response to treatment, F1 female bodyweight gains were significantly (p < 0.01; multiple t-test) inflated during maturation in association with a 250 ppm dietary exposure and significantly depressed during gestation in association with 80 and 250 ppm exposures. No significant treatment-related effects were noted during the lactation period in either F0 or F1 females. Food consumption, conversion efficiency, and water intake were unremarkable at all treatment levels in both generations of treated male and female rats. In both F0 and F1 dams exposed to dietary levels up to 250 ppm, the gestrous cycles, pre-coital interval, mating, pregnancy, fertility and gestation indices were unaffected by treatment. Reproductive effects common to both generations included a significantly extended gestation period (80, 250 ppm) and significantly reduced litter sizes at postpartum Day 1 (250 ppm). There was a slight dosage-related decrease in implantation scars noted on necropsy of F0 dams, however viability, bodyweight at postpartum Day 1, bodyweight gain, sex ratio, auditory and visual function, and all physical development parameters of the F1 offspring were comparable to controls. Upon necropsy, these F1 progeny were found with dose-related increased hydronephrosis. Bone marrow smears and absolute and relative organ weights did not indicate an untoward effects of treatment, however micropathological investigation identified increased focal nephrocalcinosis in female F1 offspring of 80 and 250 ppm parents and male offspring of the 250 ppm parents. Necropsy of F0 parents revealed no gross pathology and, although testes and epididymis of F0 males of a 250 ppm exposure were reduced, histological review identified no treatment-related changes. Conversely, F1 parents were found with gross indications of toxicity. Liver and kidney weights were significantly high (250 ppm) relative to controls, while spleen weights were low in both sexes (80, 250 ppm). Testis and epididymis weights in the males (80, 250 ppm), and pituitary gland (80, 250 ppm), uterus (80, 250 ppm), brain (250 ppm) and lung weights (250 ppm) in females were significantly reduced. Female F1 ovarian weights were increased relative to controls in association with a 250 ppm dietary exposure. Upon histological investigation, increased incidence geriatric nephropathy (both sexes, 80 and 250 ppm), distension of mesenteric and/or cervical lymph nodes (250 ppm) and increased severity of nephrocalcinosis (females, 80 and 250 ppm), and an increased slight testicular tubular atrophy in males (250 ppm) were noted. F2 female progeny of 250 ppm exposed parents were found with significantly increased absolute and relative spleen weights. Histological changes were limited to marginal increases in hydronephrosis.
[ICI AMERS INC; Fluazifop butyl: Effects Upon Reproductive Performance of Rats Treated Continuously Through 2 Generations (Final Report); 03/17/81; EPA Doc No. 88-920006849; Fiche No. OTS05543854] **UNREVIEWED**

Fluazifop butyl was evaluated for developmental toxicity in adult virgin Sprague-Dawley CD rats (160/group) administered oral doses of 0, 1, 5, 10 and 200 mg/kg/day during gestation days 6-20. No increased maternal mortality or overt toxicity was attributed to treatment. At gestation Day 21 sacrifice of the dams, a slight but significantly depressed mean bodyweight gain among those of a 200 mg/kg/day dosage was indicative of dose-related and significant (p < 0.05; Student's t-test) reduction in gravid uterus weights. Significant (p < 0.01; Student's t-tests) dosage-related reductions in fetal weights in association with treatment from 5 mg/kg/day were found to correlate with increased incidence of small fetuses. Also, placental weights were also significantly low in association with treatment at 200 mg/kg/day relative to controls. Gross pathological changes included increased incidence of diaphragmatic hernia (4.4% in association with 200 mg/kg/day) noted at all treatment levels relative to controls (0%), and slight dosage-related increased occurrence of hydroureter, partnered with a marginal increase in hydronephrosis in 200 mg/kg/day fetuses. Micropathological investigation validated dosage-related incidence of hydroureter, hydronephrosis in association with a 200 mg/kg/day regimen, and subcutaneous edema among 200 mg/kg/day fetuses. Skeletal examinations further revealed retarded ossification that was dosage-related in fetuses of gestational treatment levels of 5 mg/kg/day and above. Treatment levels of 1 mg/kg/day were associated with no toxic, reproductive or developmental consequences relative to controls under the conditions of this study.
[ICI AMERS INC; Teratology Study with Fluazifop Butyl in Rats; 06/03/81; EPA Doc No. 88-920007020; Fiche No. OTS0545395] **UNREVIEWED**


Metabolism/Pharmacokinetics:

Metabolism/Metabolites:

In plants, fluazifop-butyl is rapidly hydrolyzed to fluazifop.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**


Mechanism of Action:

Acts by interfering with ATP production.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**


Pharmacology:

Environmental Fate & Exposure:

Environmental Fate/Exposure Summary:

Fluazifop-butyl will have been released to the environment from its former use a highly selective post-emergence grass killer. If released to the atmosphere, fluazifop-butyl's measured vapor pressure of 4.1X10-7 mm Hg at 20 deg C indicates that it will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase fluazifop-butyl will be rapidly degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 13 hours. Particulate-phase fluazifop-butyl may be physically removed from the atmosphere by wet and dry deposition. If released to soil, an estimated Koc of 6700 indicates that fluazifop-butyl will be immobile. Fluazifop-butyl has been found to bind strongly with homoionic clays. Volatilization from wet and dry soil surfaces is not expected to be an important process given this compound's estimated Henry's Law constant of 2.1X10-7 atm-cu m/mole and its measured vapor pressure, respectively. Biodegradation is expected to be an important fate process for fluazifop-butyl, especially in moist soils. A half-life of less than one week was observed in moist soils, the major degradation product being fluazifop. If released into water, this compound is expected to adsorb strongly to suspended solids and sediment in the water column based on its estimated Koc. Volatilization from water surfaces is not expected to be an important fate process based on the estimated Henry's Law constant for this compound. The potential for bioconcentration in aquatic organisms is very high based on an estimated BCF of 1500. Hydrolysis half-lives of 2.2 years and 79 days have been estimated for fluazifop-butyl at pHs 7 and 8, respectively. Abiotic hydrolysis of fluazifop-butyl has been observed to be catalyzed by soil colloids. (SRC)
**PEER REVIEWED**


Artificial Pollution Sources:

Fluazifop-butyl's former use as a highly selective post-emergence grass killer(1) will have resulted in its release to the environment(SRC).
[(1) Humburg NE; Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America p. 132 (1989)]**PEER REVIEWED**


Environmental Fate:

TERRESTRIAL FATE: Based on a recommended classification scheme(1), an estimated Koc value of 6700(SRC), determined from a measured log Kow of 4.5(2) and a recommended regression-derived equation(3), indicates that fluazifop-butyl is expected to be immobile in soil(SRC). Volatilization of fluazifop-butyl from moist and dry soil surfaces is not expected to be important(SRC) given an estimated Henry's Law constant of 2.1X10-7 atm-cu m/mole(SRC), from its experimental values for vapor pressure, 4.1X10-7 mm Hg(2), and water solubility, 1 mg/l(2), and this compound's vapor pressure(2), respectively. Biodegradation of fluazifop-butyl in soil is expected to be important(SRC); fluazifop-butyl is rapidly biodegraded in moist soils, with a half-life of less than 1 week; the major degradation product being fluazifop(4).
[(1) Swann RL et al; Res Rev 85: 23 (1983) (2) Tomlin C; The Pesticide Manual. A World Compendium. Incorporating the Agrochemicals Handbook. 10th ed. Bath, UK: The Bath Press. p. 471 (1994) (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington DC: Amer Chem Soc pp. 4-9 (1990) (4) Humburg NE; Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America p. 132 (1989)]**PEER REVIEWED**

AQUATIC FATE: Based on a recommended classification scheme(1), an estimated Koc value of 6700(SRC), determined from a measured log Kow of 4.5(2) and a recommended regression-derived equation(3), indicates that fluazifop-butyl is expected to adsorb to suspended solids and sediment in water(SRC). Volatilization from water surfaces is not expected to be an important process(3,SRC) based on an estimated Henry's Law constant of 2.1X10-7 atm-cu m/mole(SRC) from its experimental values for vapor pressure, 4.1X10-7 mm Hg(2), and water solubility, 1 mg/l(2). According to a classification scheme(5), an estimated BCF of 1500(3,SRC), from a measured log Kow(2), suggests that bioconcentration in aquatic organisms is very high(SRC). Biodegradation of fluazifop-butyl in aquatic systems may be important(SRC), given its microbial degradation in moist soils(6). Hydrolysis half-lives of 2.2 years and 79 days have been estimated for fluazifop-butyl at pHs 7 and 8, respectively(7).
[(1) Swann RL et al; Res Rev 85: 23 (1983) (2) Tomlin C; The Pesticide Manual. A World Compendium. Incorporating the Agrochemicals Handbook. 10th ed. Bath, UK: The Bath Press. p. 471 (1994) (3) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington DC: Amer Chem Soc pp. 4-9, 5-4, 5-10, 15-1 to 15-29 (1990) (4) Meylan WM, Howard PH; Environ Toxicol Chem 10: 1283-93 (1991) (5) Franke C et al; Chemosphere 29: 1501-14 (1994) (6) Humburg NE; Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America p. 132 (1989) (7) Mill T et al; Environmental Fate and Exposure Studies Development of a PC-SAR for Hydrolysis: Esters, Alkyl Halides and Epoxides. EPA Contract No. 68-02-4254. Menlo Park, CA: SRI International (1987)]**PEER REVIEWED**

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), fluazifop-butyl, which has a measured vapor pressure of 4.1X10-7 mm Hg at 20 deg C(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase fluazifop-butyl is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be about 13 hours(3,SRC). Particulate-phase fluazifop-butyl may be physically removed from the air by wet and dry deposition(SRC).
[(1) Bidleman TF; Environ Sci Technol 22: 361-367 (1988) (2) Tomlin C; The Pesticide Manual. A World Compendium. Incorporating the Agrochemicals Handbook. 10th ed. Bath, UK: The Bath Press. p. 471 (1994) (3) Meylan WM, Howard PH; Chemosphere 26: 2293-99 (1993)]**PEER REVIEWED**


Environmental Biodegradation:

Fluazifop-butyl is rapidly biodegraded in moist soils, with a half-life of less than 1 week, the major degradation product being fluazifop(1). Conditions that promote microbial activity in soil, such as high moisture levels have been found to favor the degradation of fluazifop-butyl in soil(2). Fluazifop-butyl was rapidly hydrolyzed by a mixed culture enriched from a landfill leachate to fluazifop(3).
[(1) Humburg NE; Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America p. 132 (1989) (2) Negre M et al; J Environ Sci Health B28: 545-76 (1993) (3) Gennari M et al; BCPC Monogr 47:67-73 (1991)]**PEER REVIEWED**


Environmental Abiotic Degradation:

The rate constant for the vapor-phase reaction of fluazifop-butyl with photochemically-produced hydroxyl radicals has been estimated as 3.0X10-11 cu cm/molecule-sec at 25 deg C(SRC) using a structure estimation method(1,SRC). This corresponds to an atmospheric half-life of about 13 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1,SRC). A base-catalyzed second order rate constant of 0.10 L/mol-sec(SRC) was estimated using a structure estimation method(2); this corresponds to half-lives of 2.2 years and 79 days at pH values of 7 and 8, respectively(2,SRC). Abiotic hydrolysis of fluazifop-butyl has been observed to be catalyzed by soil colloids(3). Fluazifop-butyl is resistant to decomposition by ultraviolet radiation(4). Fluazifop-butyl was rapidly degraded in moist soils (65% and 100% of their field capacity moisture levels); less than 8% was recoverable after 48 hours(5). In air-dry soils (20% of field capacity moisture levels), over 90% of fluazifop-butyl was recovered after 24 and 48 hours(5).
[(1) Meylan WM, Howard PH; Chemosphere 26: 2293-99 (1993) (2) Mill T et al; Environmental Fate and Exposure Studies Development of a PC-SAR for Hydrolysis: Esters, Alkyl Halides and Epoxides. EPA Contract No. 68-02-4254. Menlo Park, CA: SRI International (1987) (3) Negre M et al; J Environ Sci Health B28: 545-76 (1993) (4) Humburg NE; Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America p. 132 (1989)]**PEER REVIEWED**


Environmental Bioconcentration:

An estimated BCF of 1500 was calculated for fluazifop-butyl(SRC), using a measured log Kow of 4.5(1) and a recommended regression-derived equation(2). According to a classification scheme(3), this BCF suggests that bioconcentration in aquatic organisms is very high(SRC).
[(1) Tomlin C; The Pesticide Manual. A World Compendium. Incorporating the Agrochemicals Handbook. 10th ed. Bath, UK: The Bath Press. p. 471 (1994) (2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington DC: Amer Chem Soc pp. 5-4, 5-10 (1990) (3) Franke C et al; Chemosphere 29: 1501-14 (1994)]**PEER REVIEWED**


Soil Adsorption/Mobility:

The Koc of fluazifop-butyl is estimated as approximately 6700(SRC), using a measured log Kow of 4.5(1) and a regression-derived equation(2,SRC). According to a recommended classification scheme(3), this estimated Koc value suggests that fluazifop-butyl is expected to be immobile in soil(SRC). Fluazifop-butyl is of low mobility in soil(4). Fluazifop-butyl has been found to bind strongly with homoionic clays(5).
[(1) Tomlin C; The Pesticide Manual. A World Compendium. Incorporating the Agrochemicals Handbook. 10th ed. Bath, UK: The Bath Press. p. 471 (1994) (2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington DC: Amer Chem Soc pp. 4-9 (1990) (3) Swann RL et al; Res Rev 85: 23 (1983) (4) Humburg NE; Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America p. 132 (1989) (5) Negre M et al; J Agric Food Chem 36: 1319-22 (1988)]**PEER REVIEWED**


Volatilization from Water/Soil:

The Henry's Law constant for fluazifop-butyl is estimated as 2.1X10-7 atm-cu m/mole(SRC) from its experimental values for vapor pressure, 4.1X10-7 mm Hg(1), and water solubility, 1 mg/l(1). This value indicates that volatilization of fluazifop-butyl from water surfaces is not expected to be an important fate process(2,SRC). Fluazifop-butyl's estimated Henry's Law constant(1,SRC) and measured vapor pressure of 4.1X10-7 mm Hg(1) indicate that volatilization from moist and dry soil surfaces, respectively, is not expected to be an important fate process(SRC).
[(1) Tomlin C; The Pesticide Manual. A World Compendium. Incorporating the Agrochemicals Handbook. 10th ed. Bath, UK: The Bath Press. p. 471 (1994) (2) Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington DC: Amer Chem Soc pp. 15-1 to 15-29 (1990)]**PEER REVIEWED**


Plant Concentrations:

Residues in potatoes and soybeans treated with fluazifop-butyl (Fusilade) were below 0.05 ug/g when harvested 90 days after herbicide application(1).
[(1) Clegg BS; J Agric Food Chem 35: 269-73 (1987)]**PEER REVIEWED**


Environmental Standards & Regulations:

FIFRA Requirements:

Tolerances are established for residues for the herbicide fluazifop-butyl(+ or -)-2-(4-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy propanoic acid (fluazifop), both free and conjugated and of (+ or -)-2-(4-(-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy propanoate (fluazifop-butyl), all expressed as fluazifop, in or on the following raw agricultural commodities: cattle, fat; cattle, meat; cattle, mbyp; cottonseed; eggs; goats, fat; goats, meat; goats, mbyp; hogs, fat; hogs, meat; hogs, mbyp; horses, fat; horses, meat; horses mbyp; milk; poultry, fat; poultry, meat; poultry, mbyp; sheep, fat; sheep, meat; sheep, mbyp; and soybeans.
[40 CFR 180.411(a) (1996)]**PEER REVIEWED**

Tolerances with regional registration are established for residues fluazifop-butyl(+ or -)-2-(4-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy propanoic acid (fluazifop), both free and conjugated and of (+ or -)butyl-2-(4-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy propanoate (fluazifop-butyl), all expressed as fluazifop, in or on the following raw agricultural commodities: peppers, tabasco.
[40 CFR 180.411(b) (1996)]**PEER REVIEWED**

Tolerances are established for residues of the resolved isomer of fluazifop, (R)-2-(4-((5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoic acid both free and conjugated and of fluazifop-P-butyl, butyl(R)-2-(4-((5-(triflluoromethyl)-2-pyridinyl)phenoxy)propanoate, all expressed as fluazifop, in or on the raw agricultural commodity: carrots ; endive; macadamia nuts; onions (bulb); pecans; spinach; stone fruits; and sweet potatoes.
[40 CFR 180.411(c) (1996)]**PEER REVIEWED**

Tolerances with regional registration ... are established for residues of the resolved isomer of the herbicide fluazifop, (R)-2-(4-((5-trifluoromethyl)-2-pyridinyl)-oxy)phenoxy)propanoic acid, both free and conjugated and of fluazifop-P-butyl, butyl(R)-2-(4-((5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoate, all expressed as fluazifop, in or on the raw agricultural commodities: asparagus; coffee; and rhubarb.
[40 CFR 180.411(d) (1996)]**PEER REVIEWED**

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. Pesticides for which EPA had not issued Registration Standards prior to the effective date of FIFRA, as amended in 1988, were divided into three lists based upon their potential for human exposure and other factors, with List B containing pesticides of greater concern and List D pesticides of less concern. Butyl (RS)-2-(4-((5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoate is found on List B. Case No: 2285; Pesticide type: herbicide; Case Status: No products containing the pesticide are actively registered ... The case /is characterized/ as "cancelled." Under FIFRA, pesticide producers may voluntarily cancel their registered products. EPA also may cancel pesticide registrations if registrants fail to pay required fees or make/meet certain reregistration commitments, or if EPA reaches findings of unreasonable adverse effects.; Active ingredient (AI): Butyl (RS)-2-(4-((5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoate; Data Call-in (DCI) Date(s): 06/12/91; AI Status: The active ingredient is no longer contained in any registered pesticide products ... "cancelled.".
[USEPA/OPP; Status of Pesticides in Registration, Reregistration and Special Review p.182 (Spring, 1998) EPA 738-R-98-002]**QC REVIEWED**


Allowable Tolerances:

Tolerances are established for residues for the herbicide fluazifop-butyl(+ or -)-2-(4-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy propanoic acid (fluazifop), both free and conjugated and of (+ or -)-2-(4-(-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy propanoate (fluazifop-butyl), all expressed as fluazifop, in or on the following raw agricultural commodities: cattle, fat 0.05 ppm; cattle, meat 0.05 ppm; cattle, mbyp 0.05 ppm; cottonseed 0.1 ppm; eggs 0.05 ppm; goats, fat 0.05 ppm; goats, meat 0.05 ppm; goats, mbyp 0.05 ppm; hogs, fat 0.05 ppm; hogs, meat 0.05 ppm; hogs, mbyp 0.05 ppm; horses, fat 0.05 ppm; horses, meat 0.05 ppm; horses mbyp 0.05 ppm; milk 0.05 ppm; poultry, fat 0.05 ppm; poultry, meat 0.05 ppm; poultry, mbyp 0.05 ppm; sheep, fat 0.05 ppm; sheep, meat 0.05 ppm; sheep, mbyp 0.05 ppm; and soybeans 1.0 ppm.
[40 CFR 180.411(a) (1996)]**PEER REVIEWED**

Tolerances with regional registration are established for residues fluazifop-butyl(+ or -)-2-(4-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy propanoic acid (fluazifop), both free and conjugated and of (+ or -)butyl-2-(4-(5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy propanoate (fluazifop-butyl), all expressed as fluazifop, in or on the following raw agricultural commodities: peppers, tabasco 1.0 ppm.
[40 CFR 180.411(b) (1996)]**PEER REVIEWED**

Tolerances are established for residues of the resolved isomer of fluazifop, (R)-2-(4-((5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoic acid both free and conjugated and of fluazifop-P-butyl, butyl(R)-2-(4-((5-(triflluoromethyl)-2-pyridinyl)phenoxy)propanoate, all expressed as fluazifop, in or on the raw agricultural commodity: carrots 2.0 ppm; endive 6.0 ppm; macadamia nuts 0.1 ppm; onions (bulb) 0.5 ppm; pecans 0.05 ppm; spinach 6.0 ppm; stone fruits 0.05 ppm; and sweet potatoes 0.5 ppm.
[40 CFR 180.411(c) (1996)]**PEER REVIEWED**

Tolerances with regional registration ... are established for residues of the resolved isomer of the herbicide fluazifop, (R)-2-(4-((5-trifluoromethyl)-2-pyridinyl)-oxy)phenoxy)propanoic acid, both free and conjugated and of fluazifop-P-butyl, butyl(R)-2-(4-((5-(trifluoromethyl)-2-pyridinyl)oxy)phenoxy)propanoate, all expressed as fluazifop, in or on the raw agricultural commodities: asparagus 3.0 ppm; coffee 0.1 ppm; and rhubarb 0.5 ppm.
[40 CFR 180.411(d) (1996)]**PEER REVIEWED**


Chemical/Physical Properties:

Molecular Formula:

C19-H20-F3-N-O4
**PEER REVIEWED**


Molecular Weight:

383.4
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**


Color/Form:

Pale straw-colored liquid.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**


Odor:

Odorless
[Humburg, N.E. (ed.). Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America, 1989. 131]**PEER REVIEWED**


Boiling Point:

165 deg C at 0.02 mm Hg
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**


Melting Point:

13 deg C
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**


Density/Specific Gravity:

1.21 g/cu cm at 20 deg C
[Humburg, N.E. (ed.). Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America, 1989. 131]**PEER REVIEWED**


Octanol/Water Partition Coefficient:

Log Kow = 4.5
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**


Solubilities:

In water, 1 mg/l at pH 6.5
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**

Miscible with acetone, cyclohexanone, hexane, methanol, dichloromethane, and xylene. In propylene glycol 24 g/l at 20 deg C.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**

In water, 2 ppm at ambient temperature.
[Humburg, N.E. (ed.). Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America, 1989. 131]**PEER REVIEWED**


Vapor Pressure:

0.055 mPa at 20 deg C
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**


Other Chemical/Physical Properties:

Resistant to decomposition by ultraviolet radiation.
[Humburg, N.E. (ed.). Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America, 1989. 131]**PEER REVIEWED**

Reasonably stable in acidic and neutral conditions, but rapidly hydrolyzed in alkaline media (pH 9).
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**


Chemical Safety & Handling:

Hazardous Decomposition:

When heated to decomposition it emits toxic fumes of F- and NOx.
[Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996. 1651]**PEER REVIEWED**


Protective Equipment & Clothing:

Protective clothing, PVC gloves when spraying Fusilade 4E. Also, apron and full face shield when handling or mixing concentrate. Refer to labels.
[Farm Chemicals Handbook 1997. Willoughby, OH: Meister Publishing Co., 1997.,p. C170]**PEER REVIEWED**


Stability/Shelf Life:

Stable for 3 yr at 25 deg C and for 6 months at 37 deg C. Reasonably stable in acidic and neutral conditions, but rapidly hydrolyzed in alkaline media (pH 9).
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 471]**PEER REVIEWED**

Tested stable in storages 40-120 deg F (5-50 deg C).
[Farm Chemicals Handbook 1997. Willoughby, OH: Meister Publishing Co., 1997.,p. C170]**PEER REVIEWED**


Disposal Methods:

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.
**PEER REVIEWED**


Occupational Exposure Standards:

Manufacturing/Use Information:

Major Uses:

The active ingredient is no longer contained in any registered pesticide products ... "cancelled."
[USEPA/OPP; Status of Pesticides in Registration, Reregistration and Special Review p.182 (Spring, 1998) EPA 738-R-98-002]**QC REVIEWED**

Selective post-emergence herbicide.
[Budavari, S. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse Station, NJ: Merck and Co., Inc., 1996. 697]**PEER REVIEWED**

Highly selective post-emergence grass killer. It will control both annual and perennial grasses.
[Humburg, N.E. (ed.). Herbicide Handbook of the Weed Science Society of America. 6th ed. Champaign, IL: Weed Science Society of America, 1989. 132]**PEER REVIEWED**


Methods of Manufacturing:

n-Butanol + 2-(4-chlorophenoxy)propionic acid + 2-hydroxy-5-(trifluoromethyl)pyridine (esterification/ether formation)
[Ashford, R.D. Ashford's Dictionary of Industrial Chemicals. London, England: Wavelength Publications Ltd., 1994. 426]**PEER REVIEWED**


General Manufacturing Information:

Not registered for use in the U.S.
[Farm Chemicals Handbook 1997. Willoughby, OH: Meister Publishing Co., 1997.,p. C-170]**PEER REVIEWED**


Formulations/Preparations:

Emulsifiable concentrate, wettable powder.
[Augustijin-Beckers PWM et al; Rev Environ Contam Toxicol 137: 1-82 (1994)]**PEER REVIEWED**


Laboratory Methods:

Analytic Laboratory Methods:

Product analysis of fluazifop-butyl by GLC with FID (AOAC Methods, 1990, 984.08; CIPAC Handbook, 1988, 1D, 106). Residues (fluazifop-butyl, fluazifop, free and conjugates) determined by HPLC of the free acid. Details available from Zeneca.
[Tomlin, C.D.S. (ed.). The Pesticide Manual - World Compendium. 10th ed. Surrey, UK: The British Crop Protection Council, 1994. 472]**PEER REVIEWED**


Special References:

Synonyms and Identifiers:

Formulations/Preparations:

Emulsifiable concentrate, wettable powder.
[Augustijin-Beckers PWM et al; Rev Environ Contam Toxicol 137: 1-82 (1994)]**PEER REVIEWED**


Administrative Information:

Hazardous Substances Databank Number: 6644

Last Revision Date: 20000929

Last Review Date: Reviewed by SRP on 9/18/1997


Update History:

Complete Update on 03/13/2000, 2 fields added/edited/deleted.
Complete Update on 06/03/1998, 43 fields added/edited/deleted.