Environment*! Protection     Qffioi o« P«BKK)« Program (TS-766C)
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control of annual weeds in bearing, nonbearing,
nursery stock, noncitrus, nut crops; 14 to 7
lb al/A in citrus nurseries; terrestrial nonfood crops
JO to 20 lb al/h; aquatic weed control 7 to 15 lb. at/ ,.
Types of Formulations: 2%, 1%, and 10% active Ingre-
dient Cal) granule (0); 50% al wettable powder
(WP); 1.73%, 1.77%. 2.1% and 3.12% at soluble
concentrate! liquid (SC/I. ,); and 6.75% al liquid
ready to use (RTU).
Usual Carriers: Water.
3. Science Findings
The current data base does not suggest any major
toxicological problems. However, there are several
toxicology data gaps: acute inhalation, dermal
sensitization, primary eye irritation, primary derrnal
irritation, oncology,reproduction studies and a teratology
study in a second species. Dichlobenil has a low
acute oral and moderate acute dermal toxicity. Acute
inhalation toxicity, primary eye and dermal irritation,
and dermal sensitization have not been characterized.
There is a potential toxicity concern regarding the
plant and soil metabolite, dichlorobenzainide (BAN).
Subchronic ingestion of 8AM produces a neuromuscular
effect in rats, not observed with the parent compound.
This metabolite is readily absorbed and translocated
by plants. Because SAM has tentatively been implicated
in adverse toxicological symptoms not attributable to
dichlobenil p se, we are requirIng additional
residue data depicting residues of 8AM.
Chemical Characteristics: P • Pure
T = technical
Physical state — (P) Crystalline solid
CT) Powder
Color — (P) White
(T) Pale yellowish
Odor - Characteristic aromatic
Melting point — (P) 1*5 to 1*6 °C
CT) 1140 to 1411 °C
Solubility — (at 20 °C)
(T) 25 ppm in water
(T) 10 g/l OC g in methylene chloride
(T) It g/100 g in toluene
Vapor pressure — (P) 5.5 x i0 mm Hg at 20 °C
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Octanol/water partition coeFd iclent — (1’) 3.fl6
‘ roxicoloqy Characteristics :
Toxicity Category and \ a1ue(s) for Each Acute
Hazard
Acute Oral Toxicity 4250 (3510—5150) mg/kg
(rat) (males and females)
Toxicity Category III
Ac te Dermal Toxicity 1350 + 158 mg/kg (males)
(rabbit) Toxici:ty Category II
Subchronic Oral Toxicity — Rodent (Rat):
Compound—related effects included
increased absolute and relative liver
and kidney weights at 1000 ppm and
above; hepatic degeneration and an
absolute neutropenia and leukopenia
at 3000 ppm and above; and mortality
(5 out of 6) and hepatic necrosis at
10,000 ppm.
No Observed Effect Level (NOEL.): 100 ppm
(50 mg/kg/day) (rodent)
Lowest Effect Level (LET..): 1000 ppm
(500 mg/kg/day) (rodent)
Nonrodent — (beaqie dogs): This requirement
is satisfied by the 2—year chronic feeding
study.
A core—minimum subchronic oral rat study was
submitted. Rats (10/sex/dose) were treated
with RAM in the diet for 13 weeks at doses
of 0, 50, 180, 600 and 2300 ppm. The NOEL
(180 ppm [ 1.4 mg/kq/day]) and the LET.. (600
ppm t49 mg/kg/day)) were based on decreased
body weight gain and food efficiency, increased
blood urea nitrogen (BUN), and reduced
coagulation times. There was also a possible
reduction in muscle tone.
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Major Routes of xposure: The maior route o exoosure
is throuq the skin d rinq mixina nñ loading.
Chronic Toxicotoqy Results:
Onconenicity — The oncoqenic ootentiM. o dichiohenil
cannot be determined from the available rat
study. A second oncogenicity study (not rat)
is needed to determine its oncogenic potential.
Chronic feeding — Nonrodent (beagle dogs): The NOEL
and LEt, were based on increased absolute and
relative liver and thyroid weiqht in both
sexes; leukocytic infiltration and fibrinoid
degeneration around the central hepatic
veins in both sexes; increases in serum
alanine aminotransferase (SGPr) (females)
and serum alkaline phosphatase (SAP) (males
and females); and liver enzyme g].ucose—6-
phosphatase and glucose-6—phosphatase
dehydrogenase (G6Pase and G6PD) activity
(males and females).
NOEL = 50 ppm (1.25 mg/kg/day) (nonrodent)
LET 3 = 350 ppm (8.75 mg/kg/day) (nonrodent)
Teratogenicity — Rodent (Rat):
Maternal Toxic NOEL = 20 mg/kg! day
Developmental NOEL = 60 mg/ka/day
Mutagenicity: Battery of mutagenicity tests for gene
mutation, chrornosornal aberration 1 direct DNA
damage and transformation are negative.
Physiological and Behavioral Characteristics :
Translocation — 2,6—Dichlorobenzamide is absorbed
by roots and trans located in the plant.
Mechanism of Pesticide Action — It stimulates oxygen
utilization and inhibits esterifzcation of
phosphorus, resulting in reduced meristemic
cell gr th and inhibition of germination.
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Metabolism and Persistence in Plants and Animals -
The available data are inadequate to evaluate
the persistence of dichlobenil in plants
and animals.
Environmental Characteristics :
Available data are insufficient to fully
assess the environmental fate and the potential
exposure of humans and nontarget organisms
to dichiobenil. Additional data are needed
to characterize the potential for dichiobenil
to enthr ground water.
Ecological Characteristics :
Based on’available data, the aquatic use of dichlobenil
presents the only major ecological concern. The
requirements for acute testing are only partially
satisfied. Dichlobenil. is slightly toxic to game
birds and moderately toxic to fish and aquatic
invertebrates.
Toxicity to fish Moderately toxic to
coldwater
(LC 50 • 6.3 mgfL)
and warmwater
fish (LC 50 5 7
to 8.3 mg/I ,)
Toxicity to Aquatic Moderately toxic
Invertebrates (EC 50 • 3.2 ppm
Toxicity to birds Slightly toxic to
pheasants at an
LC 50 — 1500 ppm.
Potential Problems Related to Endangered Species: There
are sufficient data to adequately evaluate the
hazard to endangered avian and aquatic species.
Tolerance Assessment :
-List of Crops and Tolerances - A tolerance at
0.15 part per million (ppm) has been established
for the combined negligible residues of
dichlobenil and its metabolite 2,6 dichloro—
benzoic acid (2,6—DCBA) in or on the raw agricultrual
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commodities: almond hulls, apples, avocados,
blackberries, blueberries, citrus, cranber-
ries, figs, grapes, mangoes, nuts, pears,
raspberries, and stone fruits.
Results of Tolerance Assessment - A Provisional
Acceptable Daily Intake (PADI) of’ 0.00125
mg/kg/day has been established for dichiobenil
based on a 2-year dog feeding study and a
thousand—fold safety factor. Current tolerances
result in a Theoretical Maximal Residue
Cbntribution (TMRC) of’ 0.000325 mg/kg/day
and utilizes 26 percent of the PADI.
Lj Summary of Regulatory Position and Rationale
Warning Statements Required on Labels:
Manufacturing use — Do not discharge effluent
containing this product into lakes, streams,
ponds, estuaries, oceans, or public waters
unless this product is specifically identified
and addressed in an NPDES permit. Do not
discharge effluent containing this product to
sewer systems without previously notifying
the sewage treatment plant authority. For
guidance, contact your State Water Board or
Regional Office of the EPA.
End use , aquatic weed control (nonfood) — Do not
contaminate untreated water by cleaning
of equipment or disposal of wastes. Treatment
of weed areas can result in oxygen loss from
decomposition of dead weeds. This loss can
cause fish suffocation. Therefore, treat
only 1/3 of the weed areas at a time and
wait 111 days between treatments. Consult
your State Environmental Regulatory Agency
concerning the need for a permit before
applying this product to public waters.
End use , aquatic food (cranberry) — Do not conta-
minate water by cleaning of equipment or
disposal of wastes.
End use , nonaquatic (nongranular) - Do not apply
directly to water or wetlands (swamps,
bogs, marshes, and potholes). Do not
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contaminate water by cleaning of-equipment
or disposal of’ wastes.
End use , nonaquatic (granular) - Cover, collect or
incorporate granules spilled on the soil
surface. Do not apply directly to water or
wetlands (swamps, bogs, marshes and potholes).
Do not contaminate water by cleaning of
equipment or disposal of wastes.
Worker safety label statements
‘IMPORTANT! Always wash hands, face, and arms
with soap and water before smoking, eating,
drinking, or toileting. (For norigranular
formulations: Before r ov1ng gloves, wash
them with soap and water.]
Keep all unprotected persons, children, livestock,
and pets away from treated area or where there 1.s
danger of’ drift.
Do not rub eyes or mouth with hands. If you feel
sick in any way, STOP work and get help right away.
See Statement of Practical Treatment.
5. Summary of’ Major Data Gaps
Data Due
Product Chemistry 6 to 15 months
Residue Chemistry
Nature of Residue (Metabolism) 18 Months
Residue Analytical Method 15 Months
Storage Stability 6 Months
Magnitude of’ Residues 18 Months
For Each Food Use
Environmental Fate
Hydrolysis 9 Months
Photodegradation (water/soil) 9 Months
Metabolism 27 Months
Leaching and Adsorption/ 12 Months
Desorption
-Dissipation 27 to 50 Months
Accumulation 12 to 50 Months
Toxicology
Acute Inhalation 9 Months
Primary Eye Irritation 9 Months
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Primary Dermal Irritation 9 Months
Dermal Sensitization 9 Months
Chronic Toxicity (rodent) 6 Months
Oncogenicity (mouse) 148 to 50 Months
Oncogenicity (rat) 6 Months
Teratogenicity (non-rodent) 12 Months
Reproduction (rat) 30 Months
General Metabolism 214 Months
Wildlife and Aquatic Organisms
Acute Avian Oral Toxicity 9 Months
Av1 n Subacute Dietary 9 Months
(waterfowl)
Acute Toxicity to Freshwater 9 Months
Invertebrates
F18h Early Life Stage 15 Months
Aquatic Invertebrate Life 15 Months
Cy c 1 e
Aquatic Organism Accumulation 12 Months
Nontarget Area Phytotoxicity 9 Months
6. Contact Person at EPA
Robert J. Taylor
U.S. Environmental Protection Agency
Registration Division (TS—767C)
1401 M Street SW.
Washington, D.C. 201460
(703) 557-1800
DISCLAIMER: The information presented in this Pesticide Fact Shee
is for informational, purposes only and may not be used to fulfill
data requirements for pesticide registration and reregistration.
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