monuron (Monurex, Telvar) Herbicide Profile 2/85
CHEMICAL NAME: 3-(p-chlorophenyl)-1,1-dimethylurea (56)
TRADE NAME(S): Monurex (56)
FORMULATION(S): Wettable powder 80% and technical 98% (56)
TYPE: Substituted urea herbicide
BASIC PRODUCER(S): Hopkins Agricultural Chemical Co.
P.O. Box 7532
Madison, WI 53707
STATUS: General use
PRINCIPAL USES: Monuron is somewhat more soluble in water than
diuron and has a lower coefficient of adsorption. As a soil sterilant
monuron is preferred on medium to heavy soils and under intermediate
rainfall conditions. At sterilant dosages it controls a wide range of
annual and perennial grasses and broadleaf weeds on noncrop areas.
General weed control in noncropland areas (56).
To be developed.
II. PHYSICAL PROPERTIES
MOLECULAR FORMULA: C9 H11 Cl N2 O (62)
MOLECULAR WEIGHT: 198.7 (62)
PHYSICAL STATE: Colorless crystalline solid (pure compound) (62)
MELTING POINT: 174-175 C (pure compound) (62)
VAPOR PRESSURE: 67 uPa at 25 C (pure compound) (62)
SOLUBILITY: 230 mg/l water at 25 C (pure compound) (62)
III. HEALTH HAZARD INFORMATION
OSHA STANDARD: NA
NIOSH RECOMMENDED LIMIT: NA
ACGIH RECOMMENDED LIMIT: NA
A. ACUTE TOXICITY
DERMAL: Application to the intact or abraded skin of
guinea-pigs produced no irritation or sensitization
ORAL: LD50 = 3600 mg/kg (rat) (62)
B. SUBACUTE AND CHRONIC TOXICITY:
In feeding trials NEL for rats and dogs was 250-500 mg/kg diet (62).
IV. ENVIRONMENTAL CONSIDERATIONS
To be developed.
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 sub-
stitute for a more exhaustive review of the literature nor for the
judgement of a physician or other trained professional.
If poisoning is suspected, do not wait for symptoms to develop.
Contact a physician, the nearest hospital, or the nearest Poison
KNOWN OR SUSPECTED ADVERSE EFFECTS: Many substituted ureas are
moderately irritating to skin, eyes, and mucous membranes (25).
SKIN CONTACT: Wash contaminated skin with soap and water (25).
INGESTION: Ingestions of small amounts (less than 10 mg/kg
body weight) occurring less than an hour before treatment, are probably
best treated by: Syrup of Ipecac, followed by 1-2 glasses of water.
Dose for adults and children over 12 years: 30 ml. Dose for children
under 12 years: 15 ml (25).
EYE CONTACT: Flush contaminated eyes with copious amounts of
fresh water for 15 minutes (25).
NOTES TO PHYSICIAN:
INGESTIONS of LARGE amounts (more than 10 mg/kg) occurring less than an
hour before treatment, should probably be treated by gastric lavage:
A. INTUBATE stomach and ASPIRATE contents.
B. LAVAGE stomach with slurry of ACTIVATED CHARCOAL IN 0.9% saline.
Leave 30-50 gm activated charcoal in the stomach before
C. SODIUM SULFATE, 0.25 gm/kg in tap water, as a cathartic.
CAUTION: Hydrocarbons (kerosene, petroleum distillates) are
included in some formulations of these chemicals.
Ingestion of very LARGE AMOUNTS may cause CNS
depression. In this case, IPECAC IS CONTRAINDICATED.
Also, gastric intubation incurs a risk of HYDROCARBON
PNEUMONITIS. For this reason observe the following
(1) If the victim is unconscious or obtunded and
facilities are at hand, insert an ENDOTRACHEAL TUBE
(cuffed, if available) prior to gastric intubation.
(2) Keep victim's HEAD BELOW LEVEL OF STOMACH during
intubation and lavage (Trendelenburg, or left
lateral decubitus, with head of table tipped
downward). Keep victim's head turned to the left.
(3) ASPIRATE PHARYNX as regularly as possible to remove
gagged or vomited stomach contents.
INGESTIONS occurring MORE THAN an HOUR before treatment are probably
best treated only by ACTIVATED CHARCOAL, 30-50 gm, and SODIUM or
MAGNESIUM SULFATE, 0.25 gm/kg, as described above.
There are no specific antidotes for these chemicals. Because
manifestations of toxicity do occasionally occur in peculiarly
predisposed individuals, MAINTAIN CONTACT with victim for at least 72
hours so that unexpected adverse effects can be treated promptly (25).
VI. FIRE AND EXPLOSION INFORMATION
To be developed.
To be developed.
VIII. PROTECTIVE MEASURES
STORAGE AND HANDLING: Dry formulations are stable under normal storage
conditions. May irritate eyes, nose, throat, and skin. Avoid
breathing dust or spray mist. Avoid contact with skin, eyes, and
IX. PROCEDURES FOR SPILLS AND LEAKS
IN CASE OF EMERGENCY, CALL, DAY OR NIGHT
PESTICIDE TEAM SAFETY NETWORK/CHEMTREC
X. LITERATURE CITED
25. Morgan, D.P. 1982. Recognition and management of pesticide
poisonings, 3rd ed. U.S. Environmental Protection Agency,
Washington, DC. 120 pp.
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.
62. The Pesticide Manual: A World Compendium, 7th ed. 1983. C.R.
Worthing, ed. The British Crop Protection Council, Croydon,
England. 695 pp.