vernolate (Vernam) Herbicide Profile 3/85
CHEMICAL NAME: S-propyl dipropylthiocarbamate (58)
TRADE NAME(S): Vernam (58)
FORMULATION(S): Vernam 7E, emulsifiable liquid (7 lb/gal); Vernam
10 G, granule (10%) (56).
TYPE: (Mono) thiocarbamate herbicide
BASIC PRODUCER(S): Stauffer Chemical Co.
Agricultural Chemical Div.
Westport, CT 06881
STATUS: General use
PRINCIPAL USES: Vernolate is registered for use on soybeans, peanuts,
tobacco, and sweet potatoes (58).
APPLICATION METHOD(S): For optimum weed control under normal soil and
climatic conditions, vernolate must be mechanically incorporated into the
soil to a depth of 5.0 to 7.6 cm (2 to 3 inches) immediately after
application. The most suitable types of equipment for incorporation are
disc and hooded, power-driven rotary tillers. If vernolate is applied
to extremely dry soils during very dry climatic conditions, incorporation
may be accomplished by overhead irrigation following application (58).
Controls crabgrass (Digitaria spp.), barnyardgrass (watergrass)
(Echinochloa spp.), foxtails (Setaria spp.), johnsongrass from
seedlings (Sorghum halepensel), nutsedge (Cyperus spp.), goosegrass
(Eleusine indical), and wild cane (Sorghum bicolor). Broadleaf weeds
such as pigweed (Amaranthus spp.), lambsquarters (Chenopodium album),
sicklepod (Cassia obtusifolia), carpetweed (Mollugo verticillata), and
Florida purslane (Mexican clover) (Richardia scabra) will be
controlled if application is made when conditions are favorable for
Closely related to Eptam but recommended crops show a greater degree
of tolerance while still maintaining adequate weed control. No soil
residue problem since it dissipates rapidly (8b).
II. PHYSICAL PROPERTIES
MOLECULAR FORMULA: C10 H21 NOS (58)
MOLECULAR WEIGHT: 203.4 (58)
PHYSICAL STATE: Clear liquid (99.9% pure) (62)
ODOR: Faint aromatic odor (99.9% pure) (62)
BOILING POINT: 150 C/30 mmHg (99.9% pure) (62)
VAPOR PRESSURE: 1.39 Pa at 25 C (99.9% pure) (63)
SOLUBILITY: 90 mg/l water at 20 C (99.9% pure) (62)
III. HEALTH HAZARD INFORMATION
OSHA STANDARD: None established
NIOSH RECOMMENDED LIMIT: None established
ACGIH RECOMMENDED LIMIT: None established
A. ACUTE TOXICITY
DERMAL: LD50 = >5000 mg/kg. Single dermal exposures of
5000 mg/kg did not produce observable toxicity.
Severe irritant to the skin of rabbits (Vernam 7-E)
Repeated intracutaneous injections of vernolate in
guinea pigs failed to reveal any indications that the
compound is a sensitizing agent. Definite
sensitization was established in a positive control
group, treated with p-phenylenediamine. LD50 = 4640
mg/kg (technical vernolate); 10,000 mg/kg (Vernolate
ORAL: LD50 = 1200 to 1470 mg/kg (rat, Vernam 7E) (29u).
LD50 = 1780 mg/kg (male albino rat, technical
vernolate); 1800 mg/kg (male albino rat, Vernolate
EYES: Moderate irritant to the eye of rabbits (Vernam 7-E)
B. SUBACUTE AND CHRONIC TOXICITY:
a. A 90-day subacute feeding study was conducted in rats.
A no-effect level was established at 32 mg/kg per day.
b. A 90-day subacute feeding study was conducted in dogs.
A no-effect level was established in excess of 38 mg/kg per day
IV. ENVIRONMENTAL CONSIDERATIONS
Behavior In Or On Soils
1. Adsorption and leaching characteristics in basic soil types:
Vernolate is adsorbed onto dry soil but it can be removed by
leaching. Vernolate is more resistant to leaching than EPTC.
2. Microbial breakdown: Microbial breakdown is the main mechanism by
which vernolate is lost from soils.
3. Loss from photodecomposition and/or volatilization: Vernolate is
readily lost from the soil by volatilization when the soil
surface is wet at the time of application and the herbicide is
not incorporated immediately.
4. Resultant average persistence at recommended rates: At recommended
rates of application, vernolate does not persist in soil and it
should not leave residues that could injure subsequently planted
sensitive crops. The half life in moist loam soil at 21 to 27 C
(70 to 80F) is approximately 1.5 weeks (58).
General toxicity to wildlife and fish:
a. The EC50 (shell growth inhibition) of vernolate in oysters is
>1 ppm (maximum level tested) after a 96-hr exposure.
b. The EC50 (loss of equilibrium or death) in brown shrimp
(Penaeus aztecus) is >1 ppm (maximum level tested) after
24-hr and 48-hr exposures.
c. The acute LC50 of vernolate in a juvenile estuarine species
(Leiostomus xanthurus) is >1 ppm (maximum level tested)
after 24-hr and 48-hr exposures.
d. The 96-hr LC50 in fingerling rainbow trout is 10.8 mg/L for
vernolate 6E and 9.6 mg/L for technical vernolate.
e. The LC50 (96-hr exposure) of both technical vernolate and
vernolate 6E for the three-spined stickleback (Gasterosteus
aculeatus) is between 1 and 10 ppm.
f. The 96-hr LC50 of vernolate 6E in the mosquito fish is 14.5
g. The oral LC50 of technical vernolate in the bobwhite quail is
12,000 ppm for a 7-day feed treatment. The oral LC50 of
vernolate 6E in bobwhite quail is 14,500 ppm for a
comparable regimen (58).
V. EMERGENCY AND FIRST AID PROCEDURES
The chemical information provided below has been condensed from
original source documents, primarily from "Recognition and Management
of Pesticide Poisonings", 3rd ed. by Donald P. Morgan, which have been
footnoted. This information has been provided in this form for your
convenience and general guidance only. In specific cases, further
consultation and reference may be required and is recommended. This
information is not intended as a substitute for a more exhaustive
review of the literature nor for the judgement of a physician or other
If poisoning is suspected, do not wait for symptoms to develop.
Contact a physician, the nearest hospital, or the nearest Poison
SYMPTOMS: Some of these agents ((mono)thiocarbamates) are
irritating to skin and respiratory mucous membranes, causing ITCHING,
SCRATCHY THROAT, SNEEZING, and COUGH, if excessive amounts of spray or
dust are inhaled. Apart from this effect, toxic potential is low.
Neurotoxic and post-ethanol "Antabuse" reactions are not known to occur
as a result of contact with these particular compounds (25).
SKIN CONTACT: WASH contaminating chemical from SKIN and HAIR with
soap and water. Persons sensitive to thiram (rubber-sensitive) should
be permanently REMOVED FROM CONTACT with compounds of this nature (25).
INGESTION: For Vernam 7-E: Do NOT induce vomiting. This product
contains hydrocarbon solvent. Immediately give large quantities of
water or milk, if available. If vomiting does occur, give fluids
again. Never give anything by mouth to an unconscious person. Call a
physician or the nearest Poison Control Center imemdiately (29u).
-- See NOTES TO PHYSICIAN below --
INHALATION: Remove from contaminated atmosphere. If breathing
has ceased, clear the victim's airway and start mouth-to-mouth
artificial respiration, which may be supplemented by the use of a
bag-mask respirator, or a manually-triggered, oxygen supply capable of
delivering 1 liter/second or more. If the victim is breathing, oxygen
may be administered from a demand type or continuous-flow inhalator,
preferably with a physician's advice. Contact a physician immediately
(Vernam 7E) (29u).
EYE CONTACT: FLUSH contaminate from EYES with fresh water for
10-15 minutes (25).
NOTES TO PHYSICIAN: If (mono)THIOCARBAMATE has been ingested:
A. Give SYRUP OF IPECAC, followed by 1-2 glasses of water, to induce
vomiting (adults: 30 ml; children under 12 years: 15 ml).
Following emesis, administer 30-50 gm ACTIVATED CHARCOAL to bind
toxicant remaining in the gut.
B. Follow charcoal with SODIUM OF MAGNESIUM SULFATE, 0.25 gm/kg, to
remove toxicant from the gut by catharsis (25).
VI. FIRE AND EXPLOSION INFORMATION
This liquid has a closed cup flash point of 85.6 C/186 F. It
will support combustion and may decompose under fire conditions to give
off toxic materials.
Vapors may be irritating to the respiratory tract and may cause
breathing difficulty and temporary edema. Symptoms may be delayed
several hours or longer depending upon exposure.
As in any fire, prevent human exposure to fire, smoke, fumes, or
products of combustion. Evacuate nonessential personnel from the fire
Use standard firefighting techniques in extinguishing fires
involving this product. If drums are not leaking, keep cooled with a
water spray. High pressure water hose may spread the product from
broken containers increasing contamination hazards. Use of
contaminated buildings, areas, and equipment must be prevented until
they are properly decontaminated (Vernam 8E) (29u).
No incompatibilities known or expected. Noncorrosive (58).
VIII. PROTECTIVE MEASURES
STORAGE AND HANDLING: Containers should be stored in a cool, dry, well
ventilated area. Store away from flammable materials and sources of
heat and flame. Do not store near seeds, fertilizer or foodstuffs.
Exercise due caution to prevent damage to or leakage from the
container. All food shuld be kept in a separate area, away from the
working location. Eating, drinking and smoking should be prohibited in
areas where there is potential for significant exposure to the
product. Before eating, hands and face should be thoroughly washed
PROTECTIVE CLOTHING: Dermal contact and exposure should be minimized
through the use of gloves and suitable long-sleeved clothing. Eye
contact should be prevented through the use of chemical safety glasses,
goggles, or a face shield (29u).
IX. PROCEDURES FOR SPILLS AND LEAKS
IN CASE OF EMERGENCY, CALL, DAY OR NIGHT
PESTICIDE TEAM SAFETY NETWORK/CHEMTREC
A small spill can be handled routinely. Use adequate ventilation
or wear an air supplied respirator to prevent inhalation contact. Wear
protective clothing to prevent skin and eye contact. Use the following
1. Spread a suitable absorbent such as clay on the liquid.
2. Place the sweepings in an open drum.
3. Generously cover the contaminated areas with a common household
detergent (e.g. Tide). Using a stiff brush and small amounts
of water, work the detergent into the spill material forming a
slurry. Brush the slurry into cracks and crevices; and allow
to stand for 2 to 3 minutes. Be careful to completely avoid
skin or eye contact; do not splatter on one's self or
4. Spread absorbents on the slurried liquid, and shovel the absorbed
material into an open drum.
5. Repeat if necessary.
6. Flush the area with water, while observing proper environmental
7. Seal drum and dispose of contaminated material in an approved
Large spills must be handled according to a predetermined plan.
For assistance in developing a plan, contact Stauffer's Agricultural
Chemical Division, Westport, CT 06880 (29u).
X. LITERATURE CITED
8b. Thomson, W.T. 1981. Agricultural chemicals - book 2:
herbicides. Revised ed. Thomson Publications, Fresno, CA.
25. Morgan, D.P. 1982. Recognition and management of pesticide
poisonings, 3rd ed. U.S. Environmental Protection Agency,
Washington, DC. 120 pp.
29u. Stauffer Chemical Company, Agricultural Chemical Division. 1979.
Product safety information: Vernam 7-E. Westport, CT.
56. Farm Chemicals Handbook, 70th ed. 1984. R. T. Meister, G. L.
Berg, C. Sine, S. Meister, and J. Poplyk, eds. Meister
Publishing Co., Willoughby, OH.
58. Weed Science Society of America, Herbicide Handbook Committee.
1983. Herbicide handbook of the weed science society of
America, 5th ed. Weed Science Society of America, Champaign,
IL. 515 pp.
62. The Pesticide Manual: A World Compendium, 7th ed. 1983. C.R.
Worthing, ed. The British Crop Protection Council, Croydon,
England. 695 pp.