Common name

Metribuzin/Sencor/Lexone

Chemical name

4-Amino-6-(1,1-dimethylethyl)-3-methylthio-1,2,4-triazine-5-tetrahydrogenketone

Formulation

90%/95%TC 50%/70%WP 70%/75%WDG

Descriptions

1.Melting Point:125C

2.Boiling point:312.4C at 760 mmHg

3.Flash point:142.7C

4.Vapour Pressure:0.000531mmHg at 25C

5.Molecular weight:214.288

6.Solubility : Slightly soluble

Toxicity

Metribuzin is slightly toxic via the oral route, with reported oral LD50 values

of 1090 to 2300 mg/kg in rats, 700 mg/kg in mice and 245 to 274 mg/kg

in guinea pigs. It is practically nontoxic dermally, with a dermal LD50 of

20,000 mg/kg in rabbits. The 4-hour inhalation LC50 for metribuzin

in rats is greater than 0.65 mg/L, indicating moderate toxicity via the

inhalation route. Metribuzin has been shown not to irritate the skin or eyes of

rats, rabbits, guinea pigs, or human volunteers. Effects of high acute exposure

in metribuzin poisoned rats included narcosis (stupor) and labored breathing.

Deaths occurred within 24 hours, and survivors recovered slowly without permanent

effects .

Function

Metribuzin is a selective triazine herbicide which inhibits photosynthesis of

susceptible plant species. It is used for control of annual grasses and numerous

broadleaf weeds in field and vegetable crops, in turfgrass, and on fallow lands.

Metribuzin is available as liquid suspension, water dispersible granular, and dry

flowable formulations.