MONURON Property

Melting point:

173-174 °C (lit.)

Boiling point:

301.31°C (rough estimate)

Density 

1,27 g/cm³

vapor pressure 

0Pa at 20℃

refractive index 

1.5330 (estimate)

storage temp. 

0-6°C

pka

14.22±0.70(Predicted)

form 

Crystalline Solid

color 

White

Water Solubility 

262mg/L(25 ºC)

λmax

244nm(H2O)(lit.)

Merck 

14,6261

BRN 

2097922

LogP

1.94 at 20℃

IARC

3 (Vol. Sup 7, 53) 1991

EPA Substance Registry System

Monuron (150-68-5)

Safety

Hazard Codes 

Xn,N

Risk Statements 

22-40-50/53

Safety Statements 

36/37-60-61

RIDADR 

UN 3077 9/PG 3

WGK Germany 

3

RTECS 

YS6300000

TSCA 

Yes

HazardClass 

9

PackingGroup 

III

HS Code 

29242990

Hazardous Substances Data

150-68-5(Hazardous Substances Data)

Toxicity

LD50 orally in rats: 3700 mg/kg (Bailey, White)

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

H351Suspected of causing cancer

H410Very toxic to aquatic life with long lasting effects

Precautionary statements

P202Do not handle until all safety precautions have been read and understood.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P270Do not eat, drink or smoke when using this product.

P273Avoid release to the environment.

P301+P312IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.

P308+P313IF exposed or concerned: Get medical advice/attention.

MONURON Chemical Properties,Usage,Production

Chemical Properties

White, crystalline solid; odorless. Very low solubility in water and hydrocarbonsolvents; slightly soluble in oils; partially soluble inalcohols; stable toward oxidation and moisture.

Uses

Monuron may be used as a reference standard in the determination of monuron in rice and corn using high performance liquid chromatography coupled with fluorescence detection combined with ultraviolet decomposition and post-column derivatization.

Uses

Herbicide, sugarcane-flowering suppressant.

Definition

ChEBI: A member of the class of ureas that is urea in which one of the nitrogens is substituted by a p-chlorophenyl group while the other is substituted by two methyl groups.

General Description

White crystalline solid or white powder with a slight odor. Melting point 175°C. Moderately toxic by ingestion. Used as an herbicide.

Air & Water Reactions

Insoluble in water. Is hydrolyzed slowly by acids and alkalis, and more rapidly on heating .

Reactivity Profile

MONURON is a chlorinated urea derivative. May react with azo and diazo compounds to generate toxic gases. May react with strong reducing agents to generate flammable gases. Reacts as a weak base. Combustion generates mixed oxides of nitrogen (NOx).

Hazard

Questionable carcinogen.

Health Hazard

Toxic properties are similar to Diuron; hydro-lyzes under acidic or alkaline conditions top-chloroaniline, which can cause anemia andmethemoglobinemia; LD50 data published inthe literature differ; acute and chronic tox-icity of this herbicide is probably of loworder; no reported case of human poisoning; showed clear evidence of carcinogenicity in male F344/N rats fed diets containing 750 ppm monuron for 2 years; causedcancers in the kidney and liver (NationalToxicology Program 1988); female rats andmale and female mice (B6C3F1) showed noevidence; induced cytomegaly of the renalepithelial cells in rats.
LD50 oral (rat): 3700 mg/kg (Bailey andWhite, 1965)
LD50 oral (rat): 1053 mg/kg (Lewis 1995).

Fire Hazard

Flash point data for MONURON are not available; however, MONURON is probably combustible.

Flammability and Explosibility

Not classified

Safety Profile

Moderately toxic by ingestion, intraperitoneal, and possibly other routes. Experimental teratogenic and reproductive effects. Questionable carcinogen with experimental carcinogenic data. Mutation data reported. An herbicide. When heated to decomposition it emits very toxic fumes of NOx and Cl-.

Environmental Fate

Biological. Monuron was mineralized in sewage samples obtained from a water treatment plant in Ithica, NY. (4-Chlorophenyl)urea and 4-chloroaniline were tentatively identified as metabolites (Wang et al., 1985).
Soil/Plant. In soils and plants, monuron is demethylated at the terminal nitrogen atom coupled with ring hydroxylation forming 3-(2-hydroxy-4-chlorophenyl)urea and 3-(3- hydroxy-4-chlorophenyl)urea (Hartley and Kidd, 1987). Walln?efer et al. (197
Photolytic. When an aqueous solution of monuron was exposed to sunlight or simulated sunlight, the major degradative pathways observed were the photooxidation and demethylation of the N-methyl groups (Crosby and Tang, 1969; Tanaka et al., 1982a),
Tanaka et al. (1981) studied the photolysis of monuron in dilute aqueous solutions in order to fully characterize a substituted diphenylamine that was observed in an earlier investigation (Tanaka et al., 1977). They identified this compound as an isomeric mixture containing 92% 2-chloro-4￠,5-bis(N￠,N￠-dimethylureido)biphenyl and 8% 5-chloro-2,4￠- bis(N￠,N￠-dimethylureido)biphenyl (Tanaka et al., 1981).
Tanaka et al. (1982) undertook a study to identify the several biphenyls formed in earlier photolysis studies (Tanaka et al., 1979, 1981). They identified these compounds as 2,4￠-, 3,4￠- and 4,4￠-bis-(N￠,N￠-dimethylureido)biphenyls (fenuron biphenyls) (Ta

Purification Methods

Crystallise monuron from MeOH. [Beilstein 12 IV 1191.]