United States Office of Pesticides and Toxic Substances
Environmental Protection Office of Pesticide Programs (TS-766C)
Agency Washington. DC 20460
v>EPA Pesticide
Fact Sheet
Name of Chemical: DIOOK3L
Reason for Issuance:
Date Issued: Dec. 30, 1983
Fact Sheet Number: 15
DESCRIPTION OF THE CHEMICAL
0 Generic Name: Dicofol
0 Common Name: Dicofol
0 Trade Names: Acarin", Carbax®, Decofol®, Kelthane®,
Kelthane A®, p,p' Kelthane«, Mibol*,
and Mitigan*
0 Chemical Abstracts Service (CAS) Number: 115-32-2
0 EPA Shaughnessey Number: 010501
c Year of Initial Registration: 1957
c Pesticide Type: Acaricide
0 U.S. and Foreign Producers: Rohm & Haas, Aceto,
Makhteshim Beer-sniva,
Agan Chemical, Drexel
Chemical, Tricon Chem
International, and Ida, Inc.
USE PATTERNS AND FORMULATIONS
0 Foliar spray on agricultural crops and ornamentals,
and in or around agricultural and domestic buildings
for mite control.
0 Formulated as eraulsifiable concentrates, wettable powders,
dusts, ready-to-use liquids, and aerosol sprays.
SCIENCE FINDINGS
Summary of Science Findings
0 There are insufficient data available to characterize the
environmental fate of dicofol, however, groundwater
contamination is not expected due to dicofol's lack of
mobility in soil and low leaching potential.
0 There are insufficient data available to determine the onco-
genicity, teratogenicity, mutagenicity, and chrome feeding
effects of 'dicofol.
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o The data snow that diCOfOl is highly toxic to aquatic
organisms nd o:.ly sligntiy toxic to birds, mammals, and
beneficial insects.
o Dicofol DioaccumulateS in some rotational crops and aquatic
organisms.
O The DDT analog contaminants in dicotol may cause unreasonable
adverse effects in certain bird and fish species.
Chemical Characteristics
O Manufacturing—use dicofol products contain a number of
DDT analogs as manufacturing impurities. These impurities
include the o,p’ and p,p’ isomers of DDT, DDE, DDD,
and a substance called “extra—chlorine DDT” or Cl—DDT.
o Dicofol is a nonflowable liquid (or waxy solid), ranging
from dark to yellow—brown in color. It is stable under
cool and dry conditions, is practically insoluble in
water, out soluble in organic solvents. It melting point
ranges from 58°C to 78°C. The cnemical coes not pose
any unusual handling hazards.
Toxicological Properties
o Dicofol has a moderate ac te oral toxicity (Toxicity
Category III).
o Dicotol has a relatively nigh degree ot acute dermal
toxicity (Toxicity Category II)
O Results from an eye irritation test using a formulation
intermediate indicates that the manufacturing—use
product is probably a severe eye irritant (Toxicity
Category I).
° Toxicity studies on dicotol are as follows:
— Oral LD 50 in rats: 684 - 1495 mg/kg body weight
— Oral LD 50 in rabbits: 1610 mg/kg body weiant
— Dermal LD 50 in rabbitE: 2.1 gm/kg Doay wei nt
— Eye Irritation: tests wltn a formulation intermediate
showed corneal damage in some raboits that persistec
for seven days
— Subchronic Oral Toxicity in Rats: NOEL is 20 ppm.
— Oncogenicity in Rats: Available data from tne National
Cancer Institute suggests that dicofol is a possible
oncogen. However, the study is unacceptable due to
the reported decomposition of the test material
during the test.
— Reproduction Study in Rats and Mice: The NOEL for botti
rats and mice is 100 ppm.
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Environmental Characteristics
o Dicofol was stable tor 350 days at 10 ppm in tielc plots
under aerobic conditions.
O Aged dicofol residues are negligibly mobile in sandy loam
soil column leaching studies.
o Field studies show that dicofol persists in soils for at
least 4 years after application.
o Dicofol residues may accumulate in fish as well as some
rotational crops.
Ecological Characteristics
O The DDT analog contaminants in the dicofol products can cause
reproductive impairment in various fish and flesn eating
birds (eggshell thinning).
Avian dietary LC 50 : 1237 to 3100 ppm for upland game oirds
(slightly toxic).
o Prolonged exposure to low levels (5 to 10 ppm) had no
significant effects on reproduction behavior of mallards.
o Acute 96—hour LC5O for warm water tish: 0.31 to 0.51 ppm.
o Acute 96—hour L.C 5 for cold water fish: 0.053 to 0.086 ppm.
o Acute LD 50 for marine grass shrimp: >0.439 ppm.
o Findings show that dicofol is highly toxic to aquatic
organisms.
o DicofOl impairs the reproductive physiology ot fish and
aquatic invertebrates.
o Dicofol does not seem to be phytotoxic to most plants
for which it is registered.
o Dicofol has been shown to be relatively nontoxic to honey
bees and alfalfa leafcutting bees.
Tolerance Assessment
O Current application rates on labeling exceed the rates
associated with the established tolerances. Toleranees and/or
labeling may need to be revised to correct this discrepancy.
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o Res idues of tne dicofo impurities will nave to be
exEjmined for trie tolerance reassessmen..
I. SUE’IMARY OF REGULATORY POSITION AND RATIONALE
o N’ use, formulation, or geographical restrictions are
required. General use classification.
o A Special Review of all dicofol end—use products
containing detectable amounts of DDT analogs will be
i nitiatea.
o t’Jo new registrations will be issued for new dicofol products
.ntended for outdoor use which would further increase
4 c.he amount of DDT in the environment.
o Registrants and applicants for registration of manufact-
uring—use dicofol products must agree to develop the
data as specified in the Guidance Document. Manufacturing—
use dicofol products may be registered and/or reregistered
E;uDJeCt to the terms anö conditions specified in detail withir,
t.he Guidance Document.
o F egistrants and applicants for registration must suDmit data
regarding the composition of their products and in
particular tne concentration of DDT contaminants in their
m 1 anufacturing—uSe products. Registrants must indicate the
lowest levels that could be achieved, the timetrame needed,
and the cost. The Agency is concerned about the presence
c f DDT contaminants at levels substantially below 1% of
the technical product because a no—effect—level has not
been determined for avian reproductive effects. Agency files
5;how that currently registered manufacturing—Use products
•:ontain from 9 to 15 percent DDT and DDT analog contamination.
O Studies must be conducted by the registrants to measure
whether DDT analog residues will be present on tooc or feed
crops due to the use of dicofol products. A complete
tolerance reassessment will be conducted after these
datta and other required residue data are suomitted.
5. SUMMARY OF MAJOR DATA GAPS
o product Chemistry: product identity, certification of
limits, physical and chemical properties, and special
requirements as mentioned in Item 4, above. Due
April, 1984.
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Residue Chemistry: metaDolism in plants and an imals,
residue analytical metnoas, upoatea resiaue data (in-
cluding residue data on DDT analogs) on most c;rops.
Due December, 1986.
o Environmental Fate: degradation studies, soil metabolism
studies, field volatility, field dissipation, accumulation
in fish and rotational crops. Due December, 1986.
o Toxicology: inhalation studies, subchronic feeding,
chronic toxicity, oncogenicity, teratogenici.ty, muta—
genicity, metabolism. Due December, 1986.
o Ecological Effects: avian reproduction, aquatic organism
testing. Due December, 1986.
o Special Testing For DDT Analog Contaminants: all environmental
fate studies conducted on Cl—DDT, chronic testing with
C1—DDT on chronic toxicity on oiras, fi ;r,, and aquatic
invertebrates. Due Decemoer, 1986.
6. Contact Person a: EPA : Bruce A. Kapner ( :S—767C)
Special Review Br rich
Office o Pesticiae Programs
401 M Street, S. .
Washington, D.C. 20460
Telepflone: 70.3/5E ,7—7400
DISCLAIMER: The information presented in this Chemical
Information Fact Sheet is tor intormational purposes only
and may not be used to fulfill data requirer ents for
pesticide registration and reregistration.
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