EnmrorwiMnlal Protwa.cn OH** 0( Pvt«cMt« Program (TS-766C)
Washington. DC 2O460
v>EPA Pesticide
Fact Sheet
Name of Chemical: NABA;I
Reason for Issuance: KI:CIS>|IHA-!ION SIAMVHI
Date Issued: APRIL> 1987
Fact Sheet Number: 124
DESCRIPTION OF CHEMICAL
Generic Name: Disodium ethylene bisdithiocarbamate
Common Name: Nabam
Trade Names: Chem Barn*; Dithane* D-14; Dithane* A-40; DSE»;
Nabasan*; Parzate*; Spring Bak*.
EPA Shaughnessy Code: 014503
Chemical Abstracts Service (CAS) Number: 142-59-6
Pesticide Type: Fungicide
Chemical Family: Ethylene bisdithiocarbamate (EBDC)
U. S. and Foreign Producers: Alco Chemical Corporation;
Vinnings Chemical Company;
Rohm and Haas
USE PATTERNS AND FORMULATIONS
Registered Uses: Industrial sites (cooling towers, evaporative
condensers, air washer systems, secondary oil
recovery water and drilling fluids, pulp and
paper mills, cane sugar mills, beet sugar mills).
All registered food (except £01 u»e in sugar mill
flume water) and ornamental uses of
nabam, a total of 35, are currently suspended.
t
Major Uses: Domestic usage of nabam as a pesticide (Typical
current year basis (1983-1985)): t
Sector IDS, x 1,000 Percent
Cooling Water 475 40
Sugar 425 37
Paper 275 23
Totals 1175 100
Formulation Types Registered: Ready-to-use 3.75 to 22% nabam,
Formulation Intermediates - 22.5 to 30% nabam,
and Soluble Concentrates - 22% or 93% nabam.
-------
—2—
Methods of Application: In most industrial uses, nabam is added
directly to water either by a single
dose or continuous feed.
Application Rates: Rates range from .09 to 3.0 parts per million
(ppm) in sugar processing; 30 to 120 ppm in
pulp and paper processing; 2.6 to 60 ppm in
water cooling towers. General industrial
preservative uses are in the range of 30 to
120 ppm.
Usual Carrier: Water
SCIENCE FINDINGS
Summary Science Statement : A major toxicological concern from
exposure to nabam is the hazard to the human thyroid from
presence of ethylenethiourea (ETIJ), a contaminant, degradation
product, and metabolite present in nabam and other EBDC fungi-
cides. Additional chronic studies on riabarn are required for
further evaluation. Moreover, ETU has caused developmentally
toxic/teratogenic effects in rats and hamsters. There are no
adequate teratology studies on nabam. Teratology studies
with nabam are required before its teratogenicity can be
fully assessed.
ETU has been classified as a Group B2 carcinogen in accordance
with the Agency’s Guidelines for Carcinogen Risk Assessment
(September 26, 1986, 51 CFR 33992), based on studies which
show that it induced an increased incidence of thyroid adenomas
and adenocarciriomas in rats and hepatomas in mice. Because
of the presence of ETU in nabam, the Agency is considering
whether further regulatory considerations are warranted.
Available data are not adequate to assess the environmental
fate of riabam. However, etudieB do indicate that ETU, the
major degradate of nabam, has leaching potential in certain
soil types. A complete assessment of the environmental fate,
including the potential for groundwater contamination, from
the use of nabam products will be undertaken when data are
available.
Available data are insufficient to completely evaluate the
ecological effects of nabam. Based on available data, nabam
is moderately toxic to freshwater fish; moderately to highly
toxic to certain estuarine organisms.
-------
—3—
Physical/Chemical Characteristics :
Physical state: Liquid at 25° C
Empirical Formula: C 4 H 6 N 2 Na 2 S 4
Molecular weight: 256.3
Toxicology Charateristics :
Major Route of Exposure: Dermal
Acute Toxicity:
Oral Toxicity: Toxicity category II
Dermal Sensitization: Skin sensitizer
Mutagenicity: Additional studies required
Negative — Host—mediated assay in mice in Salmonella
typhimuriuin.
Positive — Sister-chromatid exchanges in CHO cells
Negative — In Vivo bone marrow cytogenetic assay
Physiological and Behavioral Characteristics
Mechanism of Pesticidal Action: Nabain inhibits enzyme activity
by complexing with metal—containing enzymes including those
involved with the production of adenosine triphosphate (ATP).
Metabolism: Nabam appears to be rapidly absorbed from the
gastrointestinal tract, distributed to target organs and
excreted almost totally within 96 hours.
Environmental Characteristics:
Photodecomposition and/or Volatility: Studies required
Hydrolysis: Studies required
Anaerobic Aquatic Metabolism: Studies required
Leaching and adsorption/desorption studies: Nabam is slightly
mobile in certain soil types. Additional studies
required.
Ecological Characteristics:
Freshwater Fish Toxicity: Moderately toxic. Studies required.
Effects on Non—target Insects: Relatively nontoxic to honey
bees.
-------
—4—
Tolerance Assessment
There are no established tolerances for residues of nabam
se on any food or feed items. All food crop uses of nabam
are rrently suspended. When used on food crops nabam is
tank mixed with zinc sulfate leading to the formation of
zineb. Nabam is not mixed with zinc sulfate when used on
onions to control smut. Therefore, for this use registrants
are required to submit residue data on nabam. For the other
food crop uses, application actually consists of a solution
of zineb instead of nabam. Therefore, residues in agricultural
commodities treated with nabam are expected to be zineb.
The use of nabam as an industrial biocide to treat flume water
in sugar beet mills is considered to be a treatment of a raw
agricultural commodity. Regulations have been established by
the Food and Drug Administration under 21 CFR 173.320(b)(3)
for nabam residues following application to sugar mill grinding,
crusher and/or diffuser systems. The treatment of flume water,
transporting and washing systems are under EPA’s jurisdiction.
Residue data are required in this Standard to determine if
the residues concentrate in any of the processed sugar commodi-
ties.
SUMMARY OF REGULATORY POSITION AND RATIONALE
EPA is currently evaluating the potential human health
risks resulting from the food, field and food crops and
terrestrial non—food uses of nabam to determine whether
additional regulatory action is warranted on nabam and the
other EBDC pesticides containing the common contaminant,
degradation product, and metabolite, ETU. ETU is mutagenic,
oncogenic and teratogenic, and the Agency has classified it
as a Group B2 oncogen (Probable Human Carcinogen).
After considering exposure to ETU from the industrial,
non-food uses of nabam, the Agency has concluded that the
risks from exposure to ETU from use of nabam are not a concern
for most industrial uses at this time because applicator
exposure, based on available information, appears negligible.
The Agency lacks data to assess exposure to nabam from the
metalworking fluid and tanning uses. Additional information
is being required for all industrial uses. The Agency does
not believe that further regulatory action on nabam products
registered for industrial non-food uses is warranted at this
time.
The Agency will not consider any new food use tolerances for
nabam at this time. The Agency will consider the need for
establishment of tolerances for ETU and any intermediate
metabolitea when data are sufficient to permit such decisions.
While data gaps are being filled, currently registered manu-
facturing—use products (MP’s) and end-use products (EP’s)
containing nabam as the sole active ingredient may be sold
-------
—5—
distributed, formulated, and used, subject to the terms
and conditions of the naham recjistration standard. Mowever,
significant new uses will not be registered. Registrants
must provide or agree to develop and provide additional data
in order to maintain existing registrations.
The Agency has determined that all, data will be immediatel.v
reviewed as they are submitted.
Precautionary Statements Required on Labels:
Manufacturing—Use Products
“This pesticide is toxic to fish. Do not discharge
effluent containing this product into lakes, streams,
ponds, estuaries, oceans, or public water unless this
oroduct is specifically identified and addressed in an
NPDFS nermit. Pb not discharge effluent containing this
nroduct to sewer systems without previously notifying
the sewage treatment plant authority. For auidance, con-
tact your State Water Roard or Pegional Office of the EPP.”
End—Use Products
gricultural Tise Products
“This nesticide is toxic to fish. flrift and runoff
from treated areas may he hazardous to acuatic organ-
isms in neighboring areas. Do not anplv directl.v to
water or wetlands (swamps, hogs, marshes, and notholes).
P0 not contaminate water by cleaning of equipment or
disposal of wastes.”
All Home Use Products
“PWOTFC’rIV M ’kSflR S: Always spray with your hack to
the wind. Wear long—sleeve shirt, long nants, and
rubber gloves. Wash gloves thoroughly with soap and
water before removing, Change your clothes immediately
after using this product and launder separately from
other laundry items before reuse. Shower immediately
after use.”
Home Use Products with rood rises
“Preharvest intervals on this label are specified so
that nesticide residues will he at an acceptable
level when the cron Is harvested.”
All Aaricultural Products
“After (snravs have dried/dusts have settled/vanors
have dispersed, as applicable) do not enter or allow
-------
—6—
entry into treated areas until the 7 4 —hour reentry
interval has expired unless wearing the nersonal
protective eguinment listed on the label.”.
“ WORKER SAFETY RULES
J(een all unprotected nersons, children, livestock, and
pets away from treated area or where there is danger of
drift.
“no not rub eves or mouth with hands, See First Aid
(Practical Treatment Section).”
“ PERSONAL PROTECTIVE EOUIPMENT
HANDLERS (MIXERS, LOADERS, AMP APPLICATORS) AND
EARLV REENTRV WORKERS MUST WEAR THE FOLLOWING PROTECTIVF
CLOTHING ANP EOUIPMENT: a long—sleeve shirt and long
Dants or a coverall that covers all parts of the body
except the head, hands, and feet; chemical resistant
gloves; shoes, socks, and goggles or a face shield.
During mixing and loading, a chemical resistant apron
must also be worn.
During annlication from a tractor with a completely
enclosed cab with positive nressure filtration, or
aerially with an enclosed cocknit, a long—sleeve
shirt and long pants may he worn in place of the
above nrotective clothing. Chemical resistant gloves
must he available in the cab or cockpit and worn
while exiting.
IMPORTANT! Refore removing gloves, wash them with
soan and water. Always wash hands, face, and arms
with soap and water before eating, smoking or drinking.
Always wash hands and arms with soan and water before
using the toilet.
After work take off all clothes and shoes. Shower
using soap and water. Wear only clean clothes. Do
not use contaminated clothing. Wash protective
clothing and protective equipment with soap and water
after each use. Personal clothing worn during use
must be laundered separately from household articles.
Clothing and protective equipment heavily contaminated
or drenched with naham must be destroyed according
to state and local regulations.
HEAVILY CONTAMINATED OR DRENCHED CLOTHING CANNOT RE
ADF.OUATELV DECONTAMINATED.
During aerial application, human ftaggers are nrohibited
unless in totally enclosed vehicles.”
-------
—7—
Industria 1 rise Products
“This nesticirle is toxic to fish. Snil.ls, snravs, and
runoff From use site may he hazardous to aquatic organ-
isms in neighboring areas. fl not apply rlirectlv to
water or wetlands (swarnos, hogs, marshes, and notholes i.
no not contaminate water by cleaning of equipment or
disposal of wastes.”
“HANDLE (rN LunIMG MIXING, LOAfING, OR APPLYING) ‘ HIS
PRO )UC’ ONLY WHEN WEARING THE FOLLOWING PROTECTIVE CLOTHING
AMP FOUIDMFP’IT: A long—sleeve shirt and long nants or a
coverall that covers all parts of the body except the
head, hands, and feet: chemical resistant gloves; and
goggles or a face shield. flurinq mixing and loading, a
chemical resistant apron must also be worn.”
SUMMARY OF MAJOR DATA GAPS
Product Chevnjstrv — All
Residue Chemistry — Plant and animal metabolism
Residue studies
Toxicology — Acute dermal. and inhalation toxicity
Primary eye and dermal irritation
21—day suhchronic derrnaI
Chronic toxicity (rodent and nonrodent) (food uses)
flncoqenicitv (rat and rnouse)(Food uses)
Teratology (rabbit and rat)
Peproductjon (rat)
Mutacienicity (gene mutation, cell transformation,
unscheduled DNA synthesis)
Percutaneous dermal absorption
Ecological Effects — Avian oral toxicity
Avian dietary toxicity
Freshwater fish toxicity
Freshwater invertebrate toxicity
Estuarine and marine organism toxicity
Aquatic organism accumulation
Simulated or actual field testing—aquatic
organisms
Nontarget area phytotoxicity—aquatic plant
growth
Environmental Fate — Hydrolysis
Photodegradatlon (water, soil)
Aerobic and anaerobic soil metabolism
Aerobic and anaerobic aquatic metabolism
Leaching and adsorntion/desorntiOn
-------
—8—
Volatility (laboratory)
Field dissipation (terrestrial,aquatic)
Rotational crops (confined)
Fish accumulation
Reentry — Reentry protection studies
- Ethylenethiourea (ETU ) —
Toxicology — Chronic (rodent and nonrodent)
Reproduction
Dermal (percutaneous) absorption
Mutagenicity (promotion)
Environmental Fate - Hydrolysis
Photodegradation (soil and water)
Aerobic and anaerobic soil metabolism
Leaching and adaorption/desorption
Degradation (soil)
CONTACT PERSON AT EPA
Ms. Lois Rossi
Acting Product Manager (Team 2’)
Fungicide-Herbicide Branch
Registration Division (TS767C)
Office of Pesticide Programs, EPA
Washington, D.C. 20460
Telephone: 703—557—1900
DISCLAIMER : The information presented in this Pesticide Fact
Sheet is for Information purposes only and may not be used to
fulfil data requirements for pesticide registration and reregis-
tration.
------- |