United Statw office of Pesticides and Toxic Substances
Environmental Protection Office of Pesticide Program* (TS-766C)
Agency Washington. DC 20460
vvEPA Pesticide
Fact Sheet
Name of Chemical: PERFHJUXJNE
Reason for Issuance:
Date Issued: Sept. 30, 1985
Fact Sheet Number:
74
1. Description of the chemical:
Generic name: 1,1,l-trifluoro-N-[2-methyl-4-(phenylsulfonyl)-
phenyl]-methanesulfonamide
Empirical formula: Ci ^1^12^3^0432
Common name: Perfluidone
Trade name: Destun*
Chemical Abstracts Service (CAS) Registry number: 37924-13-2
Office of Pesticides Program's EPA Chemical Code Number:
108001
Year of initial registration: 1976
Pesticide type: Herbicide
Chemical family: Sulfonamide
U.S. producer: 3 M Company
2. Use patterns and formulations:
Application sites: Perfluidone is registered for control of
nutsedge species, certain grasses, and broadleaf weeds in
flue-cured tobacco.
Type of formulation: Perfluidone is available in a wettable
powder formulation.
Types and methods of applications: Perfluidone is banded or
broadcast applied to the soil surface with ground equip-
ment as a preemergence spray.
Application rates: 1.5 Ibs a.i./A on crop sites.
Usual carriers: Water.
3. Science Findings:
Summary science statements:
Perfluidone is not acutely toxic by the dermal and ocular
routes of exposure. A 90-day dog feeding study showed
liver disorders (hepatic lesions, hepatocyte vacuolation,
hyalin degeneration and biliary stasis) at the two highest
dose levels (400 and 800 ppra).
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The available data are insufficient to show that any of
the risk criteria listed in § 162.11(a) of Title 140 of
the U.S. Code of Federal Regulations have been met or
exceeded for the uses of perfiuldone at the present time.
There are no valid mutagenicity and teratogenicity studies
for perfiuldone. There are also residue chemistry and
environmental fate data gaps.
Perfiuldone is slightly toxic to freshwater fish species.
Studies regarding freshwater invertebrates are not accept-
able and there are no marine/estuarine data. A detailed
ecological hazard assessment cannot be made until certain
environmental chemistry data requirements have been met.
Chemical characteristics:
Perfluidone is a solid at room temperature and is odorless.
Its molecular weight is 379.140. The melting point is 1143—
1145°C. Perfluidone is soluble in water (at 20°C) to 60.0
ug/mi and soluble in aromatic and chlorinated hydrocarbon
solvents.
Toxicological characteristics:
Acute toxicology effects of perfluidone are as follows:
Acute Dermal Toxicity in rabbits: >14,000 mg/kg body
weight, Toxicity Category III
Skin irritation in rabbits: Not an irritant, Toxicity
Category IV
Eye irritation in rabbits: Moderate eye irritant, Toxicity
Category II.
Subchronic toxicology effects of perfiuldone are as
follows:
A 90—day dog feeding study showed liver disorders (hepatic
lesions, hepatocyte vacuolation, hyalin degeneration and
biliary stasis) at the two highest dose levels (1400 and
800 ppm).
Chronic toxicology effects on perfluidone have not been
evaluated because there are no valid teratogenicity
studies in either the rat or rabbit, and no mutagenicity
tests.
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Major routes of human exposure:
Non—dietary exposure of applicators to perfluidone dur-
ing mixing, loading, 8praylng and flagging is probable.
Physiological and biochemical behavioral characteristics:
Translocation: Perfiuldone is mobile in the xylem but is
of limited mobility in the phloem.
Mechanism of pesticidal action: Perfiuldone inhibits photo—
system I of the photosynthetic process.
Environmental characteristics:
Adsorption and leaching in basic soil types: Perfluidone
will leach through wet, neutral or slightly alkaline
soils, with a tendency toward greater leaching in soils
having low clay and organic matter. Leaching occurs to
a lesser extent in acidic soil.
Microbial breakdown: Soil microorganisms play a significant
role in the degradation of perfluidone in the soil.
Loss from photodecomposition and/or volatilization: Photo-
decomposition and/or volatilization play an important
role in the degradation of perfluidone on or in soil.
Average persistence at recommended rates: When used at re-
commended rates under normal environmental conditions,
the half life of perfluidone in the soil is approximately
one month.
Ecological characteristics:
96—hour fish toxicity: 147.5 ppm for bluegill sunfish
(practically non—toxic) and 17.0 ppm for rainbow trout
(slightly toxic).
Potential problem for endangered species:
Perfluidone was reviewed by the Agency under the endan-
gered 8pecies cotton cluster, but it did not exceed any
trigger. On flue—cured tobacco, If the maximum rate of
1.5 pounds active ingredient/acre were applied to six
inches of water, the resulting residues (0.754 ppm) are
less than 0.900 ppm (1/20 of the LC 50 of the most sensi-
tive fish). Therefore, perfluidone 1 s use on tobacco is
not expected to adversely affect the endangered species
and no endangered species label statements are required.
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Tolerance assessments:
The Agency is not conducting a tolerance reassessment -on
perfluidone because the only use is on flue—cured tobacco.
This use is a non—food and non—feed use which does not re-
quire a tolerance. Therefore, the Agency will not require
residue chemistry data on the metabolism of perfluidone
and related metabolite(s) in crops and animals.
Problems known to have occurred with use:
Since perfluidorie has never been commercially manufactured
or sold in the United States, it has not been identified
in the Pesticide Incident Monitoring System (PIMS) nor
implicated in any incident.
14• Summary of regulatory position and rationale :
Based on the review and evaluation of all available data and
other relevant information on perfluidone, the Agency has
made the following determinations:
The available data are insufficient to indicate that any
of the risk criteria listed in § 162.11(a) of Title 40
of the U.S. Code of Federal Regulations have been met or
exceeded for the uses of perfluidone at the present time.
Perfluidone is not acutely toxic by the derinal and ocular
routes of exposure. A 90—day dog feeding study showed
liver disorders (hepatic lesions, hepatocyte vacuolation,
hyalin degeneration and biliary stasis) at the two highest
dose levels ( 00 and 800 ppm).
The absence of other toxicological data prevents the Agency
from determining the acute, subacute and chronic effects of
perfluidone. Given the lack of data, the most appropriate
action is to move quickly to fill the data gaps. When data
are submitted and reviewed, the Agency will determine the
registrability of the affected use pattern.
The data base supporting the perfiuldone tolerance on cot-
ton seed (0.01 ppm) has been reviewed and found to be in-
adequate. However, the data tables in the perfluidone
registration standard will not include these data gaps
attributable to the tolerance on cottonseed: S 158.135
Toxicology , Subchronic Testing (82—1 ), Chronic Testing
(83—1, 83—2, 83—Li), Special Testing (85—1); § 158.125
Residue Chemistry , Livestock (171-14), Animal Residues
(171—14), Cottonseed (171—Li) and Meat/Milk/Poultry/Eggs
(171—14). Instead, the Agency will Issue a Proposed Rule
to revoke the perfiuldone tolerance on cottonseed. If
there Is no response to support the tolerance, the Agency
will issue a Notice of Tolerance Revocation.
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End-use product (EP) labels will be required to bear a
revised environmental hazard statement
EP labels will be required to bear a rotational crop res-
triction.
EP labels will be required to bear a protective clothing
state ment for mixers, loaders, and applicators.
Manufacturing—use product (MP) labels will be required to
bear a statement regarding discharge to bodies of water
and sewer systems.
The Agency will not require a ground water advisory state-
ment at this time. If additional data indicate that per-
fluldone may cause ground water concerns, the Agency may
reconsider this decision.
No endangered species label statements are required.
The Agency is not requiring a reentry interval for the
registered use of perfluidone.
Specific label warning statement:
Hazard Information
The human hazard statements must appear on all EP labels
as presribed in 1 10 CFR 162.10.
Environmental Hazard Statements
All MPs intended for formulation into EPs must bear
the following statements:
“Do not discharge effluent containing this product di-
rectly into lakes, streams, ponds, estuaries, oceans or
public waters unless this product is specifically iden-
tified and addressed in a National Pollutant Discharge
Elimination System (NPDES) permit. Do not discharge
effluent containing this product into sewer systems
without previously notifying the sewage treatment plant
authority. For guidance, contact your State Water Board
or Regional Office of the Environmental Protection
Agency”.
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End-Use Product Statements
The following environmental hazard statement must appear
on all EP products:
“Do not apply directly to water or wetlands. Do not con-
taminate water by cleaning of equipment or disposal of
wastes”.
The following rotational crop restriction statement must
appear on all EP products:
“Limitations: Replant only tobacco in DESTUN® herbicide-
treated soil during the year of application and the fol-
lowing crop year”.
The following protective clothing statement must appear
on all EP products:
“During mixing/loading or application, wear gloves imper-
meable to perfluidone. When handling the concentrated
product, wear a dust mask and chemical resistant apron
in addition to the gloves. Wash hands thoroughly with
soap and water after handling and before eating, urina-
ting or smoking. Remove and wash clothing before reuse.
Clothing should be laundered separately from household
articles. Replace gloves frequently. Used gloves and
clothing which has been drenched or heavily contaminated
should be disposed of in accordance with state or local
regulations”.
5. Summary of major data gaps :
The toxicological studies are required on the following
dates:
An acute oral toxicity study (June 30, 1986),
An acute Inhalation toxicity study (June 30, 1986),
A dermal sensitization study (June 30, 1986),
A 21—day derTnal toxicity study (September 30, 1986),
Two teratogenicity studies (December 30, 1986), and
Mutagenicity studies (June—September 1986).
The environmental fate data are required on the following
dates:
An hydrolysis study (June 30, 1986),
A photodegradatlon study (June 30, 1986),
An aerobic soil study (December 30, 1987),
A mobility/leaching study (September 30, 1986), and
A dissipation/soil study (December 30, 1987).
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The ecological effects data are required on the following
dates: -
An acute avian oral toxicity study (June 30, 1986),
Two avian subacute dietary toxicity studies (June 30,
1986),
Two freshwater fish toxicity studies (June 30, 1986), and
An acute freshwater invertebrate. toxicity study (June
30, 1986).
Product chemistry data are required during 1986.
6. Contact Person at EPA :
Robert J.Taylor
Office of Pesticide Programs, EPA,
Registration Division (TS—767C)
Fungicide-Herbicide Branch
401 M Street., S.W.
Washington, DC 201460.
(703) 557—1800
DISCLAIMER: The information presented in this Pesticide Fact
Sheet is for informational purposes only and may not be used
to fulfill data requirements for pesticide registration and
reregistration.
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