United Statej Office of Pertleidei and Toxic Substances
Environmental ProMction Office of Pesticide Programs (TS-766C)
Agency Washington, DC 20460
&EPA Pesticide
Fact Sheet
Name of Chemical: HEPTACHLOR
Reason for Issuance: REGISTRATION STANDARD
Date Issued: DECEMBER 1986
Fact Sheet Number:
1. DESCRIPTION OF CHEMICAL
Generic Name: 1,4,5,6,7,8,8-heptachloro-3a,4 ,7,7a-tetra-
(Chemical) hydro-4,7-methano-lH indene
Common Name: Heptachlor
Trade and Other Names: 1,4,5,6,7,8,8-heptachloro-3a,4,7 , 7a-
tetrahydro-4,7-methanoindene; E-3314; Velsicol 104; Hep-
tagran; Heptalube; heptachlore; Drinox H-34; Gold Crest
H-60; Heptamul; and Heptox
EPA Shaughnessy Code: 044801
Chemical Abstracts Service (CAS) Number: 76-44-8
Year of Initial Registration: 1952
Pesticide Type: Insecticide
Chemical Family: Chlorinated cyclodiene
U.S. and Foreign Producers: Velsicol Chemical Corporation
2. USE PATTERNS AND FORMULATIONS
Application Sites: Soil surrounding wooden structures for
termite control; control of fire ants in buried cable
closures; above-ground structural application for control
of termites and Bother wood-destroying insects.
Types of Formulations: Emulsifiable concentrates; granular.
Types and Methods of Application: Trenching, rodding, subslab
injection, and low-pressure spray for subsurface termite
control; caulking gun, trowel, or brush for applying to
s tr uc t ur a1 wood.
Application Rates: 0.06 to 1.0% emulsion for termite control;
0.2 oz/buried cable closure size 1 sq ft.
3. SCIENCE FINDINGS
Summary Science Statement: Heptachlor is a chlorinated
cyclodiene with moderate acute toxicity. The chemical has
demonstrated adverse chronic effects in mice (causing liver
tumors). Heptachlor may pose a significant health risk of
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chronic liver effects to occupants of structures treated
with heptachior for termite control. This risk may be
determined to be of regulatory concern, pending further
evaluation. Heptachior is extremely toxic to aquatic
organisms and birds. Heptachlor is persistent and bioaccum-
ulates. Heptachlor may have a potential for contaminating
surface water; thus, a special study is required to delineate
this potential. Applicator exposure studies are required
to determine whether exposure to applicators may be posing
health risks. Special prociuct—specific subacute inhalation
testing is required to evaluate the short—term respiratory
hazards to humans in structures treated with heptachlor.
An inhalation study of one (1) year duration using rats is
required to assess potential hazards to humans in treated
residences from this route of exposure. The Agency has been
apprised of reported cases of optic neuritis associated
with termiticide treatment of homes with a related cyclodiene,
chiordane. To determine whether this is a significant health
effect, and whether heptachior plays a role, the registrant
must have eye tissue from the required 2—year rat oncogenicity
study analyzed by neuropathologists specializing in optic
tissue pathology. Data available to the Agency show an occur-
rence of misuse and misapplication of heptachlor. The
Agency is requiring restricted use classification of all
end—use products (EPs) containing heptachior. Application
must be made either in the actual physical presence of a
Certified Applicator or if the Certified Applicator is not
physically present at the site, each Uncertified Applicator
must have completed a State—approved training course for
termiticide application meeting minimal EPA training
requirements and be registered in the State in which the
Uncertified Applicator is working.
Chemical/Physical Characteristics of the Technical Material
Physical State: Crystalline solid
Color: White
Odor: Mild camphor-like odor
Molecular Weight and ormula: 373.3 — C 10 H 5 C 1 7
Melting Point: 95 to 96 °C
Boiling Point: 135—145 °C at 1—1.5 nunflg
Density: 1.65—1.67 g/mL at 65° C
Vapor Pressure: 0.0003 mmHg at 25 °C
Solubility in Various Solvents: Soluble in ethanol, xylene,
carbon tetrachloride, acetone,
and benzene; practically
insoluble in water.
Stability: Stable in daylight, air, moisture, and moderate
heat.
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Toxicology Characteristics
Acute Oral: Data gap (except for a 74% technical formulation
which showed the oral LD 50 value for male and
female rats to be 208 mg/kg and 158 mg/kg,
respectively. This places the 74% technical
into Toxicity Category II).
Acute Dermal: Data gap
Primary Dermal Irritation: Data gap
Primary Eye Irritation: Data gap
Skin Sensitization: Not a sensitizer
Acute Inhalation: Data gap
Subacute Inhalation (2—week product—specific test using rats
or guinea piqs): Data gap
Chronic Inhalation (1 year using rats): Data gap
Major Routes of Exposure: Inhalation exposure to occupants
of treated structures; dermal and
respiratory exposure to termiticide
applicators.
Delayed Neurotoxicity: Does not cause delayed neurotoxic
effects.
Oncogenicity: This chemical is classified as a Group B 2
oncogen (probable human oncogen).
There are three long—term carcinoqenesis
bioassays of heptachior in mice, which were
independently conducted by investigators
affiliated with the National Cancer Institute,
the International Research and Development
Corporation, and the Food and Drug Administra-
tion. Reported in these studies were significant
tumor responses in three different strains of
mice (C 3 H, CF 1 , and B6C3F 1 ) in males and females
with a dose—related increase in the proportion of
tumors that were malignant. Available data
from five existing carcinoqenicity bioassays
in rats are inadequate and inconclusive and a
well—designed study in rats for heptachior
epoxide is needed to determine the carcinogenic
potential of heptachior in this species.
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Chronic Feeding: Based on a dog chronic feeding study with
heptachior epoxide, a lowest, effect level
(LEL) of 0.0125 mg/kg/day for liver effects
has been calculated.
Data gaps exist for rodents and nonrodents
for heptachlor epoxide and for heptachlor
in nonrodents.
Metabolism: In biological systems, heptachior is readily
epoxidized to heptachior epoxide.
Teratogenicity: Data gap
Reproduction: A NOEL of 1.0 ppm has been set for repro-
ductive effects to the young; the liver is
- the target organ of effect.
Mutagenicity: Sufficient evidence exists to conclude that
neither heptachior nor heptachior epoxide
possesses mutagenic activity in bacteria.
Further testing is required to fulfill
mutagenicity testing requirements in all
three categories (gene mutation, structural
chromosome aberrations, and other genotoxic
effects).
Physiological and Biochemical Characteristics
The precise mode of action in biological systems is not
known. In humans, signs of acute intoxication are primar-
ily related to the central nervous system, including
hyperexcitabilty, convulsions, depression, and death.
Environmental Characteristics
Data gaps exist for all applicable studies. However,
available supplementary data indicate general trends of
heptachior behavio in the environment. Heptachior is
persistent and bioaccumulates. Heptachior is not expected
to leach, since it is insoluble in water and should adsorb
to the soil surface. Thus, it should not reach underground
aquifers. However, additional data are necessary to fully
assess the potential for ground water contamination as a
result of heptachior’s termiticide use.
Ecological Characteristics (technical grade)
Avian Oral Toxicity: Data gap
Avian Dietary Toxicity: 92, 224, and 480 ppm in bobwhite
(8 days) . quail, pheasant, and mallard duck,
respectively.
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Freshwater Fish Acute Toxicity: 13 ug/L for bluegill;
(96—hr LC 50 ) 7.4 ug/L for rainbow trout.
Freshwater Invertebrate Toxicity: 42 ug/L for Daphnia pulex ;
(48—hr or 96—hr EC5O) 1.1 ug/L for Pteronarcys .
4. Required Unique Labeling and Regulatory Position Summary
o EPA is currently evaluating the potential human health
risks of 1) nononcogenic chronic liver effects, and 2)
oncogenic effects to determine whether additional action
on heptachlor may be warranted.
o In order to meet the statutory standard for continued
registration, retail sale and use of all EP5 containing
heptachior must be restricted to Certified Applicators or
persons under their direct supervision. For purposes of
heptachlor use, direct supervision by a Certified Applicator
means 1) the actual physical presence of a Certified
Applicator at the application site during application, or
2) if the Certified Applicator is not physically present
at the site, each Uncertified Applicator must have completed
a State—approved training course in termiticide application
meeting minimal EPA training requirements and be registered
in the State in which the Uncertified Applicator is working.
The Certified Applicator must be available if and when
needed.
o In order to meet the statutory standard for continued
registration, heptachior product labels must be revised to
provide specific disposal procedures and provide fish
and wildlife toxicity warnings.
o The Agency is requiring a special monitoring study to
evaluate whether and to what extent surface water contam-
ination may be resulting from the use of heptachlor as a
termiticide.
c
o A new 2—year rat oncogenicity study is needed to determine
the carcinogenic potential of heptachior epoxide.
o Special product—specific subacute inhalation testing is
required to evaluate the respiratory hazards to humans in
structures treated with termiticide products containing
heptachior.
o Evaluation of eye tissue from the required 2—year rat
oncogenicity study is required to determine whether hepta—
chlor’s termiticide use may be causing optic neuritis in
humans.
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o The Agency is requiring the submission of applicator exposure
data from dermal and respiratory routes of exposure.
o While data gaps are being filled, currently registered
manufacturing—use products and EPs containing heptachlor may
be sold, distributed, formulated, and used, subject to the
terms and conditions specified in the Registration Standard
for heptachlor , and any additional regulatory action taken
by the Agency. Registrants must provide or agree to develop
additional data in order to maintain existing registrations.
5. TOLERANCE REASSESSMENT
No tolerance reassessment for heptachior is necessary, since
there are no longer any food or feed uses. EPA is proceeding
to revoke existing heptachlor tolerances and replace them with
action levels. A Final Rule is scheduled for publication in
the FEDERAL REGISTER in early 1987.
6. SUMMARY OF MAJOR DATA GAPS
o Hydrolysis
o Photodegradation in water
o Aerobic soil metabolism
o Anaerobic soil metabolism
o Leaching and adsorption/desorptiofl
o Aerobic aquatic metabolism
o Soil dissipation
o Chronic feeding — nonrodents and rats (heptachior epoxide)
non—rodents (heptachior)
o Oncogenicity — rats (heptachior epoxide)
o Teratogenicity
o Rat oncogenicity study
o Mutagenicity studies
o Acute toxicity studies
o Optic tissue pathology
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o Special surface water monitoring stuales
o Applicator exposure studies
o Indoor air exposure studies
o Special product—specific subchronic inhalation study
(2—week duration using rats or guinea pigs)
o Subchronic inhalation study (1—year duration using rats)
o Avian acute oral toxicity
o All product chemistry studies
7. CONTACT PERSON AT EPA
George LaRocca
Product Manager (15)
Insecticide—Rodenticide Branch
Registration Division (TS—767C)
Office of Pesticide Programs
Environmental Protection Agency’
401 M Street SW.
Washington, DC 20460
Office location and telephone number:
Room 204, Crystal Mall #2
1921 Jefferson Davis Highway
Arlington, VA 22202
(703) 557—2386
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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