Environmental Piottcttofi
OHiea of Patttefcto and Toxic Sutetaneai
OHiee of Pactidde Progranv (T6-766CI
Washington. DC 20480
vvEPA.    Pesticide
                 Fact Sheet
                 Name of Chemical:
                 Reason for Issuance:
                 Date Issued:
                 Fact Sheet Number:
         Registration Standard
         June 6, 1988


       Generic  Name:
       Common Names:
       Trade Names:

       EPA Shaughnessy Code:

       Chemical Abstracts
        Service (CAS) Number:

       Year of Initial

       Pesticide Type:

       Chemical Family:

       U.S.  Producer:

 Dimethyl tetrachloro-

 No common name has been
 assigned; DCPA is commonly
 used; other names in use are
 chlorothal and chlorothal-





 Chlorinated benzoic  acids

 Fermenta Plant Protection
       Application sites:  Terrestrial food crops (Agricultural
          Crops), Terrestrial  Nonfood Crops (Agricultural Crops),
          Ornamental Plants and  Forest Trees,  Domestic Outdoor
          (Ornamental Plants and Forest Trees).

Types of formulations: Formulation intermediates containing
50, 75 and 90 percent DCPA; Wettable Powders containing
25, 50, 60 75, and 90 percent DCPA and granulars contain-
ing 1.15 to 24.0 percent DCPA.
Types and methods of application:
Applied with ground or aerial equipment to soil
pre—emergence to weed seed germination, broadcast or
in bands, either post—plant, post—transplant or at
layby. Applied to ornamental turf and lawns with
either spray or granular equipment before weed seed
Usual carrier: Water and fertilizers.
Summary Science Statement : DCPA and its metabolites
appear to have low acute and chronic toxicity based on
the limited studies that are available. However, these
products contain 2,3,7,8—tetrachlorodibenzo—p—dioxin
(2,3,7,8—TCDD) and hexachlorobenzene (1KB) as impurities
from the manufacturing of technical DCPA. These impurities
have chronic toxicological properties (including oncogenic,
teratogenic, fetotoxic, mutagenic or adverse effects on
immune response in mammals) that are of particular concern
in the reregistration of DCPA pesticide products. The
Agency has classified both these impurities as Probable
Human Carcinogens (Group B2). The Agency has performed
preliminary assessments of the risks posed by these im-
purities and is requiring environmental fate and residue
chemistry studies on the impurities in order to refine
these risk assessments.
ç emical _ characteristics :
Physical state: Crystalline solid
Color White
Odor Odorless
Melting point 156°C
Solubi]ity Insoluble in water, high
in aromatic hydrocarbon

Toxicolocical Characteristics of DCPA :
— Acute toxicity: Data gap.
— Dermal sensitizaton: Not a sensitizer in guinea pig.
— Subchronic toxicity: Data gap.
— Chronic toxicity: In an acceptable chronic oral
toxicity of DCPA in dogs, four male and four female
beagle dogs were dosed with DCPA at 100, 1,000, and
10,000 ppm in their diet. No compound—related effects
were observed. The NOEL was 10,000 ppm.
In a chronic toxicity study in rats, 35 male and 35
female rats were dosed with DCPA at 100, 1,000 and
10,000 ppm in their diets for 2 years. At termination
of the study, the kidney weights in males and the
adrenal weights of females were significantly higher than
controls. The NOEL was 1,000 ppm (50 mg/kg/day). The
LEL was 10,000 ppm (500 mg/kg/day).
— Oncogenicity: Data gap.
— Reproductive toxicity: Data gap.
— Teratology: Twenty—five bred female Charles River
rats were fed 500, 1,000, and 2,000 mg/kg/day. No
compound related effects were observed in the dams
or the fetuses at the highest dose tested.
— Mutagenicity: DCPA did not induce toxic effects in in
an in yivo dominant lethal study when administered to
male rats in a single treatment of 3.16, 31.6 and 316
mg/kg prior to mating.
— Metabolism: Data gap.
Physiological and Biochemical Characteristics :
— Mechanism of pesticidal action: DCPA appears to inhibit
the normal cell division of root tips of a wide spectrum
of plants. The precise mechanism of this effect is
not understood.
— Metabolism and persistence in plants and animals:
Plants : Radio—labeled DCPA was not translocated from
treated leaves of cotton plants. If applied to soil
or nutrient solution roots of cotton plants appeared
to absorb it and translocate it to the stems and foliage
of the plants. Monomethyl tetrachloroterephthalate
(MTP) and tetrachloroterephthalic acid (TPA) and DCPA
have been detected in residue studies from numerous
agricultural commodities.

Animals : Non—radiolabe]ed studies have detected DCPA, MTP
and TPA in ruminants and poultry. 14 C—DCPA studies
are needed for both metabolism of DCPA in animals and
Environmental Characteristics :
— Environmental fate data include a hydrolysis study
which indicates that DCPA is stable to hydrolysis for
up to 36 days.
— Data gaps exist for all other environmental fate
— DCPA and its degradates were detected in ground water
samples in four states. The highest level detected
was 1139 parts per billion (ppb). The Agency has
proposed a drinking water health advisory level of
3500 ppb. A ground water monitoring study is required
to assess the extent of ground water contamination.
Ecological Characteristics :
— Acute avian oral toxicity: data gap.
— Avian dietary toxicity: data gap.
— Avian reproductive toxicty: data gap.
— Freshwater fish acute toxicity: LC 50 = >100 to >320
ppm (practically nontoxic) for bluegill sun fish and
LC 50 = 30 ppm (slightly toxic) for rainbow trout.
— Freshwater invertebrate acute toxicity: EC 50 ranged
from 27 ppm to 135 ppm (slightly to practically
nontoxic) for Daphnia maana . LC 50 >100 ppm (practically
nontoxic) for Chironomus plumosus . LC 50 >6.2 ppm (
moderately toxic) for arnmarus pseudolimnacus .
— Estuarine and marine organisms acute toxicity: LC 50
> 1,000 gIL (practically nontoxic) for Brown shrimp
( Penaeus aztecus) . LC 50 = 620 ug/L (practically non—
toxic) fpr Eastern oyster ( Crassostrea virainica) .
LC 50 = >1,000 ug/L (practicallyThontoxic) for Sheepshead
Minnow ( çyprinodon variegatus) .
— Available information suggests there is no acute hazard
to endangered aquatic species. No terrestrial endangered
species have been associated with the use patterns of
DCPA products. No data are available to evaluate
the hazard to endangered avian species or endangered
aquatic plant species.

Tolerance assessment :
- Tolerances have been established for residues of DCPA on
raw agricultural commodities. (See table on the following
page for a listing of tolerances.)
- Using a Provisional Acceptable Daily Intake (PADI)
of 0.5 mg/kg/day based on the NOEL of 50 mg/kg/day
observed in a chronic toxicity rat study, the Maximum
Permissible Intake (MPI) for a 60 kg person is 30.0
mg/kg/day. Using this value, the Agency calculates
that existing tolerances occupy 1.3 % of the ADI.
A. The Agency will not initiate a Special Review on DCPA
at this time. There are presently no chronic toxico-
logical concerns for exposures to DCPA; however
concerns for the chronic toxicological effects of
the two manufacturing impurities 2,37,8-TCDD and
HCB have not been resolved by the available
At the present time the Agency does not consider the
risks due to 237,8-TCDD from the use of DCPA be
unreasonable. The highest risk estimated was 10-6
for agricultural applicators and PCOs.
The Agency is concerned about the risks due to HCB
from the use of DCPA which are 10-6 for dietary
exposure and i - for agricultural applicators,
PCOs and a child exposed while playing on a treated
lawn. The applicator exposures can be reduced by
using protective clothing. The uncertainties in
the exposure estimates used to assess the risk to
children playing on a DCPA-treated lawn are so great
that the Agency believes that the risk assessment
cannot be used to determine whether criteria for
inititing a Special Review have been exceeded.
These exposure esitimates will be refined when data
on foliar and soil exposure to HCB become available.
The Agency believes the dietary risk to 11CR from
DCPA uses is acceptable while required metabolism
and residue data are being developed.
B. The Agency is not classifying any DCPA uses as
being for restricted use. As discussed above, the
uncertainties in the exposure estimates are very
great. Accordingly, the Agency is unable to conclude
that the risk posed by DCPA warrants its classifica-
tion as a restricted use pesticide. The Agency will
reconsider this position when the data it is requiring
become available.

Table 1. Tolerances in parts per million (ppm) for residues of
DCPA and metabolites MTP and TPA.
Raw Agricultural Commodity U.S.
Beans, field dry 2
Beans, mung, dry 2
Beans, snap, succulent 2
Broccoli 1
Brussels sprouts 1
Cabbage 1
Cantaloupes 1
Cauliflower 1
Collards 2
corn, field, fodder 0.4
corn, field, forage 0.4
Corn, grain (including
field and pop) 0.05
corn, pop, fodder 0.4
Corn, pop, forage 0.4
Corn, sweet (K + CWHR) 0.05
Corn, sweet, fodder 0.4
Corn, sweet, forage 0.4
Cottonseed 0.02
Cress, upland 5
Cucumbers 1.
Eggplant 1
Garlic 1
Honeydew melons 1
Horseradish 2
Kale 2
Lettuce 2
Mustard, greens 5
Onions 1
Peas, southern, black—eyed 2
Peppers 2
Pimentos 2
Potatoes 2
Radish, roots 2.0
Radish, tops 15.0
Rutabagas 2
Soybeans 2
Squash, summer 1
Squash, winter 1
Strawberries 2
Sweet potatoes 2
Tomatoes 1
Turnips 2
Turnips, greens 5
Watermelons 1
Yams 2

C. The Agency is requiring registrants to certify
that the levels of 2,3,7,8—TCDD and HCB in DCPA used
to formulate their products do not exceed 0.1 ppb
and 0.3 percent, respectively. This measure will
assure that the levels of these impurities in commer-
cially available DCPA products do not exceed the
reported maximum levels upon which the Agency based
its risk assessment. Registrants must also analyze
their products for other species of dioxins and
establish certified limits for these impurities as
D. The Agency will not register any significant new uses
of DCPA until product chemistry, toxicology and
residue chemistry data gaps have been filled.
E. The Agency is requiring ground water monitoring
studies to assses the extent of ground water
contamination. Because of the low toxicity of DCPA,
the low levels observed in ground water to date, and
the limited number of observations of ground water
contamination, the Agency finds that additional
regulatory action is not warranted.
F. The Agency is requiring dietary exposure information
on DCPA impurities in order to determine the nature
and magnitude of 2,3,7,8—TCDD and HCB residues. If
these data show that these impurities or their
rnetabolites accumulate in DCPA—treated agricultural
commodities to levels that raise concerns about
dietary risk, the Agency may find that additional
regulatory action is warranted.
G. The Agency is requiring dislodgeable residue and
foliar dissipation data on HCB in order to estimate
dermal exposure to this impurity. These data are
needed to refine the estimates of HCB exposure to
farm workers and to users of DCPA—treated lawns.
H. The Agency is requiring the use of protective clothing
and equipment for all uses of DCPA. End—use products
registered for agricultural use or for professional
use on ornamental turf must be labeled as follows:
Wear a longsleeved shirt and long—legged pants
and chemical resistant gloves.

IMPORTANTt If pesticide comes in contact with
skin, wash off with soap and water. Always
wash hands, face, and arms with soap and water
before smoking, eating, drinking, or toileting.
AFTER WORK: Before removing gloves, wash them
with soap and water. Take off all work clothes
and shoes. Shower using soap and water. Do not
reuse contaminated clothing. Clothing worn
during work must be laundered separately from
household articles. Clothing that becomes heavily
contaminated or drenched must be destroyed
according to State and local regulations.
End use products registered for homeowner uses must be
labled as follows:
CLOTHING: Wear long—sleeved shirt and long—legged
pants and chemical resistant gloves.
IMPORTANTI If the pesticide comes in contact
with skin wash of f with soap and water. Always
wash hands, face, and arms with soap and water
before smoking, eating, drinking, or toileting.
AFTER USE: Before removing gloves, wash them
with soap and water. Take off all work clothes
and shoes. Shower using soap and water. Do not
reuse contaminated clothing. Clothing worn
during use must be laundered separately from
household articles.
I. The Agency is imposing an interim 24—hr reentry
interval for agricultural crop uses of DCPA pesticide
products until required reentry data have been found
to support a different reentry interval. End—use
products registered for agricultural crop use must
be labled as follows:
Do not enter treated areas for 24 hours after ap-
plication unless wearing long sleeved shirt and
long pants.
J. The Agency is imposing a required precautionary
statement, environmental hazard statements, and
statement of practical treatment, as follows:
All products must bear the following precautionary

Causes moderate eye irritation. Avoid contact
with eyes or clothing. Wash thoroughly with soap
and water after handling.
All manufacturing use products must bear the following
environmental hazard statement :
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.
All nongranular end—use products must bear the following
environmental hazard statements:
Do not apply directly to water or wetlands (swamps,
bogs, marshes, and potholes). Do not contaminate
water when disposing of equipment wastewater.
All granular end—use products must bear the following
environmental hazard statements:
Collect and 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.
All products must bear the following statements of
practical treatment:
If in Eyes : Flush with plenty of water. Call a
physican if irritation persists.
K. The Agency has determined that the following studies
will receive priority review:
158.120 product Chemistry
61—2 Description of Beginning Materials and
Manufacturing Process
61—3 Discussion of Formation of Impurities
62—1 Preliminary Analysis

158.125 Residue Chemistry — DCPA
171—4 Nature of Residue (Metabolism)
171—4 Residue Analytical Method
—Plant Residues
—Animal Residues
171—4 Storage Stability Data
158.125 Residue Chemistry — Impurities
171—4 Nature of Residue (Metabolism)
171—4 Residue Analytical Method
—Plant Residues
—Animal Residues
171—4 Storage Stability Data
158.130 Environmental Fate
163—1 Leaching and Adsorption/Desorption
132—1 Foliar Dissipation
133—3 Derrnal Exposure (Conditional, at option of Registrant)
133—4 Inhalation Exposure (Conditinal, at option of
—— Ground Water Monitoring
Product Chemistry
Acute testing
Subchronic testing
Chronic testing
Special testing
Environmental Fate:
Metabolism Studies — Laboratory
Mobility Studies
Dissipation Studies — Field
Accumulation Studies
Sub—division K, Reentry Studies
Ground water Monitoring
Ecological Effects:
Avian Testing
Aquatic Organism Testing
Nontarget Area Phytotoxicity

Residue Chemistry for DCPA Products:
Metabolism in Plants and Livestock
Residue Analytical Methods f or Plants and Animals
Storage Stability Data for Raw Agricultural Commodities
Magnitude of Residues in Food and Feed Commodities
Residue Chemistry for Impurities in DCPA Products:
Metabolism in Plants
Residue Analytical Methods for Plant Residues
Magnitude of Residues in Raw Agricultural Commodities
Richard P. Mountfort
Product Manager (23)
Fungicide-Herbicide Branch
Registration Division (TS—767C)
Office of Pesticide Programs
Environmental Protection Agency
401 M Street, S.W.
Washington, DC 20460
Office Location and _ Telephone Number :
Room 237, Crystal Mall Building #2
1921 Jefferson Davis Highway
Arlington, VA 22202
DISCLAIMER: The information presented in this Pesticide Fact
Sheet is for informational purposes only and may not be used
to fulfill data reguirements for pesticide registration and
reregistration. The complete Registration Standard for DCPA
may be obtained from the National Technical Information Service
(NTIS), Port Royal Road, Springfield, VA 22152 (Telephone
No. 703—487—4650). Price for paper copies vary depending on
the length of the document, microfiche copies are $5.95 each.
When ordering you must furnish the NTIS with the stock number.
The stock number may be obtained from the contact person
identified above.