Untt«J Stftm Offic* of Pvttekta and Toxic
Emironimntal Protection Offic* of PtMtddt Programs (TS-766C)
Agency Wadiington. DC 20460
vvEPA Pesticide
Fact Sheet
Name of Chemical:
Reason for Issuance:
Date Issued: Septanber 30, 1983
Fact Sheet Number: n
1. DESCRIPTION Or CHEMICAL
Generic Name: N,N-dimethyl-N'-(3-[I(methylamino)carbonyl)
oxyjphenyl] methanimidamide nonohydrochloride
Common Name: Pormetanate hydrochloride(HCl)
Trade Name: Carzol
EPA Shaughnessy Code: 097301
Chemical Abstracts Service (CAS) Number: 23422-53-9
Year of Initial Registration: 1969
Pesticide Type: Acaricide/Insecticide
Chemical Family: methylcarbamate hydrochloride
U.S. and Foreign Producers: Imported into the U.S. from West
Germany where it is manufactured by Schering A.G. Chemical
Company. In the U.S., the sole importer and distributor of
the chemical is Nor-Am Chemical Company.
2. USE PATTERNS AND FORMULATIONS
Application Sites: Citrus, pc*e and stone fruits and alfalfa
grown-for-seed.
Types of Formulations: 92% soluble powder
Types of Methods of Application: Ground and aerial
Application Rates: Range from 0.0575 Ibs. a.i./A to 1.38 Ibs.
a. i./A
Usual Carriers: Hater
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3. SCIENCE FINDINGS
Su ary Science Statement
Formetanate D cl is highly toxic from an oral route of exposure.
It demonstrates low toxicity from the dermal route of exposure
and moderate toxicity from the inhalation route of exposure.
it is considered to be an eye irritant. The chronic studies
ar ’s data gaps.
Formetanate HC1 appears to leach in soil and therefore has a
potential for contamination of groundwater. However, avail-
able data are insufficient to fully assess the environmental
fate of this chemical. A 24—hour reentry interval has been
established.
This chemical is highly toxic to birds. It is slightly toxic
to fish and moderately toxic to estuarine and marine organisms.
A tolerance reassessment cannot be made until the studies re-
quired to fill the toxicology data gaps have been submitted and
validated. A petition for a tolerance for residues in or on
alfalfa hay and alfalfa forage must be submitted. A food
additive petition must be submitted for apple pomace.
Chemical Characteristics
Physical State: Crystalline solid
Color: White
Odor: Essentially odorless
Nelting point: 200—202 C
Toxicology Char çteristice
Acute Oral LD 50 : 26.4 ag/kg (rat), Toxicity Category I
Acute Dermal LD 50 : > 10,000 mg/kg (rabbit), Toxicity Category 111
Primary Dermal Irritation: No irritation (rabbit), Toxicity
Category IV
Primary Eye Irritation: One—fifth of the animals (rabbit) showed
irritation at a 7—day observation period. The effect was
considered to be presumptively not reversible in 21 days.
Acute Inhalation LC : 0.29 mg/liter (rat), Toxicity Category II
The chronic studies are data gaps. The original studies
were conducted by IBT and have been determined to be in-
valid. No replacement studies have been submitted. A
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commitment has been made by Nor-Am Chemical Company to
replace the IBT studies.
A risk assessment cannot be completed at this time due to
gaps in the data base.
Physiological and Biochemical Behavioral Ctraracteristjcs
Mechanism of Pesticidal Action: A contact insecticide which
causes reversible carbamylation of the acetylcholinesterage
enzyme. Poisoning also impairs the central nervous system
function.
Metabolism and Persistence in Plants and Animals: In
plants, formetanate HC1 is absorbed into the leaves but
is not translocated to untreated areas. On the fruit,
weathering and growth dilution appear to be the primary
cause of the dissipation of formetanate Rd. In animals,
formetanate is eliminated in the urine and feces. The
major metabolic pathway involves hydrolysis to metabolites
and subsequent formation of the glucuronide and ethereal
sulfate con)ugates of m—acetamidophenol.
Environmental Characteristics
Available data are insufficient to fully assess the environ-
mental fate of formetanate Rd. It appears to rapidly
degrade in soil under aerobic conditions. This chemical
appears to leach in soil and, therefore has a potential for
groundwater contamination. A 24—hour reentry interval has
been established for this chemical on orchard crops.
Ecological Characteristics
Avian oral LD 50 -
Mallard duck: 11.7 mg/kg
Bobwhite quail: 43.1 mg/kg
The avian dietary LC 50 studies, freshwater fish LC 50 studies
and acute LCso freshwater invertebrate studies are data
gaps.
Formetanate HC1 is characterized as highly toxic to birds.
It is slightly toxic to warawater fish and moderately toxic
to eatuarine and marine organisms. It is moderately toxic
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to honey bees with direct contact spray, but it has very
low toxicity to bees when they are exposed to residues on
plants.
Tolerance Assessments
A full tolerance reassessment cannot be completed because of
certain residue chemistry and toxicology data gaps. The
current values for the acceptable daily intake intake(ADI)
of 0.025 mg/kg/day and the maximum permissible intake(MpI)
of 1.5 mg/kg/day are provisional. This Is because a number
of multiple dose toxicity studies submitted to establish the
ADI/MPI were conducted by IBT and have been determined to be
invalid. Another reassessment and recalculation will be
made when the studies required to fill the toxicology data
gaps are submitted and reviewed.
A petition for tolerance for residues in or on alfalfa
forage and alfalfa hay must be submitted to support the
alfalfa grown-for—seed use. No residue data are available.
A petition for a food additive tolerace for apple pomace
must be submitted.
Tolerances:
Commodity Parts Per Million
Peaches 5
Grapefruit 4
Lemons 4
Limes 4
Nectarjnes 4
Oranges 4
Tangerines 4
Apples 3
Pears 3
Plums(fresh prunes) 2
4. SUMMARY OF REGULATORY POSITION AND RATIONALE
The Agency has determined that it should continue to allow
the registration of tormetanate HC1. Adequate studies are
available to assess the acute toxicological effects of
formetanate HC1 to humans. None of the criteria for unrea-
sonable adverse effects listed in 40 CFR S162.1l(a) have
been met or exceeded. However, because of gaps in the data
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base a full risk assessment of formetanate MCi cannot be
made at this time.
A full tolerance reassessment cannot be completed because of
residue chemistry and tozicology data gaps.
Available data are insufficient to fully assess the environ-
mental fate of carbaryl. A 24—hour reentry interval has
been established for tormetanate MC ].. This chemical appears
to have the potential to contaminate groundwater.
5 • SUMMARY OF MAJOR DATA GAPS
Residue data on alfalfa
Chronic feeding studies — 2 species
Oncogenicity studies — 2 species
Teratogenicity studies — 2 species
Reproduction studies — 2 species
Hydrolysis study
Nobility studies
Photodegradation studies
Dissipation studies
Avian dietary LC 50 studies
Aquatic organism testing
6. CONTACT PERSON AT EPA
Jay S. Ellenberger
Product Manager (12)
Insecticide—Rodenticide Branch
Regiatra on Divis ion (TS—767C)
Office of Pesticide Programs
Environmental Protection Agency
401 N Street, S. W.
Washington, D. C. 20460
Office location and telephone number:
Room 202, Crystal Mall 02
1921 Jefferson Davis Highway
Arlington, VA 22202
(703) 557—2386
DISCLAIMER: The information presented in this Chemical Information
Pact Sheet is for informational purposes only and may not be used
to fulfill data requirements for pesticide registration and
reregistration.
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