United Statw
Environ man taT Protection
Agancy
Offica of PMticidai and Toxic Sufactanco
Offica of PMiddi Programs (TS-766C)
Washington, DC 20460
&EPA Pesticide
Fact Sheet
Name of Chemical: tktmeihacafb
Reason for Issuance:
Date Issued: septa^^ 30, 1935
Fact Sheet Number:	76
DESCRIPTION OF CHEMICAL
Generic Name: >2,3,5- and :,3,4^5-trlmethylijhenyl
roethy.lcarbamate
-.CommonName: Trimethacarb
-	Trade Names: ' Broot* and Landrln*
-	EPA Shaughnessy Codes: 102401 (3,4,5-isomer)
102402 (2,3,5-lsomer)
-	Chemical Abstracts Service (CAS) Numbers:
2686-99-9 (3,4,5-lsomer)
3971-89-9 (2,3,5-lsomer)
-	Year of Initial Registration: 1973
-	Pesticide Type: Insecticide
-	Chemical Family: Carbamate
-	U.S. Producer: Union Carbide Agricultural Products
Company, Inc.
USE PATTERNS AND FORMULATIONS
-	Application sites: Field corn and popcorn
-	Types of formulations: 15% granular
50% wettable powder
-	Types, and methods of applications: ground application as a
granular or spray
-	Application rates: 0.9 - 1-35 lb active Ingredient/acre
SCIENCE FINDINGS
Chemical Characteristics
-	Technical trimethacarb Is a buff to brown crystalline powder
with a mild ester odor. The melting point Is 105 - 1140C.
-	Trimethacarb Is soluble In water to 58 ppm at 23°C and
hydrolyzes to trlmethylphenols, CO2, and methylamlne at pH
values greater than pH 8.
Toxicology Characteristics
-	Acute oral: 125 mg/kg (rat), Toxicity Category II
-	Acute dermal: 2 gm/kg (rabbit), Toxicity Category III
-	Primary Eye Irritation: slight eye Irritation (rabbit),
Toxicity Category III

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Toxicology Characteristics
-	Acute Inhalation: Data gap
-	Primary Skin Irritation: Non irritant, Toxicity Category IV
-	Skin Sensitization: Data gap
-	Major Routes of Exposure: Human exposure from trimethacarb
applications is from handling, mixing and application.
Major exposure is expected to be mainly dermal. Because of
trimethacarb's low dermal toxicity protective clothing is
not required.
-	Oncogenicity: Data Gap
-	Metabolism: Data Gap
-	Teratology: Data Gap
-•Reproduction: Data Gap
-	Mutagenicity: Data Gap
SPhysiological and Biochemical Characteristics
-	-Mechanism of pesticidal actions Choiinesterase inhibition
-	Metabolism and persistence in plants and animals: systemic
in plants. Like other carbamates, it is metabolized rapidly
in animals.
F.rwi rnnmpnf a 1 Charartcri i rs
-	Available data are insufficient to fully assess the
environmental fate of trimethacarb. Data gaps exist for
all required studies.
Ecological Characteristics
-	Avian acute oral toxicity: Data Gap
-	Avian dietary toxicity: 2300 ppm for Mallard Duck^ 4_SQfl
ppm for Ring-Neck Pheasant, and 2000 ppm for Japanese
Quail (slightly toxic)
-	Freshwater Fish toxicity: Cold water species (rainbow
trout) — 1.0 mg/1 (highly toxic); warm water species (blue
gill) — 11.6 mg/1 (slightly toxic).
-	Aquatic freshwater invertebrate toxicity: Data Gap ,
-	Additional data are required to fully characterize the
ecological effects of trimethacarb.

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Tolerance Assessment
Established tolerances are published in 40 CFR 180.305
to cover the sum of the residues of both components
(3,4,5 and 2,3,5-trimethylphenyl methylcarbamate) of
trimethacarb and they are:
Commod i ty
Parts Per Million
field corn
popcorn
0.1
0.1
0.1
0.1
corn fodder
corn forage
-	The Agency is unable to complete a full tolerance assessment
for the:' established tolerances t>ecausef;of certain, residue
chemistry and signifdcant -toxicology data'gaps.
-	The residue data for triitiethacarb in or on corn grain, corn
fodder .and forage are not adequate to -support the established
tolerances. Additional data are required.
-	Data are required to determine whether food additive
tolerances are needed for residues in processed products of
-	Residue data must be submitted and a tolerance must be
proposed for residues in or on corn silage.
-	A pregrazing restriction must be proposed for corn forage.
-	Based on the established*=-tolerances the theoretical maximum
residue contribution (TMRC) for trimethacarb residues in
the human diet is 0.0016 mg/day for a 60 kg person with a
1.5 kg diet. However, no acceptable chronic toxicology
exists for calculation of the acceptable daily intake (ADI).
Summary of Regulatory Position and Rationale
-	The Agency has determined that it should continue to allow
the registration of trimethacarb. None of the criteria for
unreasonable adverse effects listed in the regulations
(§162.11(a)) have been met or exceeded. However, because
of gaps in the data base a full risk assessment cannot be
completed.
-	For end-use products, the product label must include a crop
rotation statement that permits crop rotation only in
trimethacarb treated soil with those crops registered for
trimethacarb. This restriction is imposed until the Agency
has adequate accumulation data from typical rotated crops
or tolerances are established on these crops.
corn.

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-	Also, a full tolerance reassessment cannot be completed
because of major residue chemistry and toxicology data
gaps. Until these gaps are filled trlmethacarb will not be
registered for any significant new uses.
-	Available data are Insufficient to fully assess the
environmental fate of and the ecological effects from
trlmethacarb.
Summary of Major Data Gaps
-	The full complement of chronic toxicology requirements:
chronic feeding, oncogenicity, reproduction, teratology and
mutagenicity.
-	The full complement of environmental fate data 'requirements:
degradation ('hydrolysis- and photodegradatlon in water),
soil metabolism, mobility, dissipation and accumulation.
-	Additional data are required : acute avian oral toxicity
and freshwater Invertebrate acute toxicity.
-	Additional data are necessary to characterize the distribution
and--metabolism of trlmethacarb In mature corn plants.
Contact Person at EPA
Jay S. Ellenberger
Product Manager (12)
Insectlclde-Rodentlclde Branch
Registration Division ..WS-767C)
Office of Pesticide Programs
Environmental Protection Agency
401 M. Street, S.W.
Washington, D.C. 20460
Office location and telephone number:
Room 202, Crystal Mall Building #2
1921 Jefferson Davis Highway
Arlington, VA 22202
703-557-2386
DISCLAIMER: THE INFORMATION PRESENTED IN THIS CHEMICAL
INFORMATION FACT SHEET IS FOR INFORMATIONAL PURPOSES
ONLY AND NOT TO BE USED TO FULFILL DATA REQUIREMENTS FOR
PESTICIDE REGISTRATION AND REREGISTRATION.

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