Specification :

Tebuconazole

Common name: tebuconazole
IUPAC name: ( RS) -1-p-chlorophenyl-4, 4-dimethyl-3-( 1H-1, 2, 4-triazol-1-ylmethyl) pentan-3-o l
Chemical Abstracts name: ( ± ) -± -[ 2-( 4-chlorophenyl) ethyl] -± -( 1, 1-dimethylethyl) -1H-1, 2, 4-triazole-1-ethanol
Other names: fenetrazole* ; terbuconazole* ; terbutrazole* ; ethyltrianol*
CAS RN: [ 107534-96-3]

PHYSICAL CHEMISTRY
Composition: Racemate. Mol. wt.: 307.8; M.f.: C16H22ClN3O Form: Colourless crystals; ( tech., colourless to light brown powder) . M.p.: 105 º C; V.p.: 1.7x 10-3 mPa ( 20 º C) ( OECD 104) . KOW: logP = 3.7 ( 20 ° C) . Henry: 1x10-5 Pa m3 mol-1 ( 20 ° C) . S.g./ density: 1.25 ( 26 ° C) . Solubility: In water 36 mg/ l ( pH 5-9, 20 º C) . In dichloromethane > 200, isopropanol, toluene 50-100, hexane 1 y ( pH 4-9, 22 ° C) . See also Environmental Fate.

APPLICATIONS
Biochemistry: Steroid demethylation ( ergosterol biosynthesis) inhibitor.
Mode of action: Systemic fungicide with protective, curative, and eradicant action. Rapidly absorbed into the vegetative parts of the plant, with translocation principally acropetally. Uses: As a seed dressing, tebuconazole is effective against various smut and bunt diseases of cereals such as Tilletia spp., Ustilago spp., and Urocystis spp., also against Septoria nodorum ( seed-borne) , at 1-3 g/ dt seed; and Sphacelotheca reiliana in maize, at 7.5 g/ dt seed. As a spray, tebuconazole controls numerous pathogens in various crops including: rust species ( Puccinia spp.) at 125-250 g/ ha, powdery mildew ( Erysiphe graminis) at 200-250 g/ ha, scald ( Rhynchosporium secalis) at 200-312 g/ ha, Septoria spp. at 200-250 g/ ha, Pyrenophora spp. at 200-312 g/ ha, Cochliobolus sativus at 150-200 g/ ha, and head scab ( Fusarium spp.) at 188-250 g/ ha, in cereals; leaf spots ( Mycosphaerella spp.) at 125-250 g/ ha, leaf rust ( Puccinia arachidis) at 125 g/ ha, and Sclerotium rolfsii at 200-250 g/ ha, in peanuts; black leaf streak ( Mycosphaerella fijiensis) at 100 g/ ha, in bananas; stem rot ( Sclerotinia sclerotiorum) at 250-375 g/ ha, Alternaria spp. at 150-250 g/ ha, stem canker ( Leptosphaeria maculans) at 250 g/ ha, and Pyrenopeziza brassicae at 125-250 g/ ha, in oilseed rape; blister blight ( Exobasidium vexans) at 25 g/ ha, in tea; Phakopsora pachyrhizi at 100-150 g/ ha, in soya beans; Monilinia spp. at 12.5-18.8 g/ 100 l, powdery mildew ( Podosphaera leucotricha) at 10.0-12.5 g/ 100 l, Sphaerotheca pannosa at 12.5-18.8 g/ 100 l, scab ( Venturia spp.) at 7.5-10.0 g/ 100 l, white rot in apples ( Botryosphaeria dothidea) at 25 g/ 100 l, in pome and stone fruit; powdery mildew ( Uncinula necator) at 100 g/ ha, in grapevines; rust ( Hemileia vastatrix) at 125-250 g/ ha, berry spot disease ( Cercospora coffeicola) at 188-250 g/ ha, and American leaf disease ( Mycena citricolor) at 125-188 g/ ha, in coffee; white rot ( Sclerotium cepivorum) at 250-375 g/ ha, and purple blotch ( Alternaria porri) at 125-250 g/ ha, in bulb vegetables; leaf spot ( Phaeoisariopsis griseola) at 250 g/ ha, in beans; early blight ( Alternaria solani) at 150-200 g/ ha, in tomatoes and potatoes.
Phytotoxicity: Good plant compatibility in most crops with any formulation, and achieved in more sensitive crops by appropriate formulations, e.g. WP, WG or SC.
Formulation types DS; EC; ES; EW; FS; GF; SC; SE; WG; WP; WS.

MAMMALIAN TOXICOLOGY
Oral: Acute oral LD50 for male rats 4000, female rats 1700, mice c. 3000 mg/ kg.
Skin and eye: Acute percutaneous LD50 for rats > 5000 mg/ kg. Non-irritating to skin; mild irritant to eyes ( rabbits) .
Inhalation: LC50 ( 4 h) for rats 0.37 mg/ l air ( aerosol) , > 5.1 mg/ l ( dust) .
NOEL: ( 2 y) for rats 300, dogs 100, mice 20 mg/ kg diet.
ADI: 0.03 mg/ kg b.w.
Toxicity class: WHO ( a.i.) III; EPA ( formulation) II ( ' Elite' 45DF) ; III ( ' Folicur' 3.6F)
EC hazard: ( Xn; R22)

ECOTOXICOLOGY
Birds: Acute oral LD50 for male Japanese quail 4438, female Japanese quail 2912, bobwhite quail 1988 mg/ kg b.w. Dietary LC50 ( 5 d) for mallard ducks > 4816, bobwhite quail > 5000 mg/ kg feed.
Fish: LC50 ( 96 h) for rainbow trout 4.4, bluegill sunfish 5.7 mg/ l ( flow through) .
Daphnia: LC50 ( 48 h) 4.2 mg/ l ( flow through) .
Algae: ErC50 ( 96 h) for Scenedesmus subspicatus 4.01 mg/ l ( static) .
Other aquatic spp.: No effect on Chironomus riparius at 0.1 mg/ l ( 28 d) .
Bees: LD50 ( 48 h) ( oral) 175.8 ug/ bee; ( contact) 0.6 ug/ bee.
Worms: Acute LC50 ( 14 d) for Eisenia foetida 1381 mg/ kg dry soil.
Other beneficial spp.: No adverse effects on ground dwellers, e.g. ground beetles ( Poecilus cupreus) ( adults and larvae) or on foliage dwellers, e.g. ladybirds ( Coccinella septempunctata) , up to 375 g/ ha ( EW 250 formulation) .

ENVIRONMENTAL FATE
Animals: After three days, elimination was almost complete ( > 99% ) . Tebuconazole was excreted with the urine and the faeces.
Plants: Metabolism studies on wheat, grapes and peanuts show that tebuconazole is the major terminal residue. The metabolites detected were mainly triazole-containing compounds of no toxicological relevance. In plant tissue, a mean half-life of 12 days could be derived ( cereals) .
Soil/ Environment: The degradation of tebuconazole in soil was slow in laboratory studies. Under field conditions, the compound degraded much more rapidly, and did not accumulate in long-term studies ( 3-5 y) . Since no residues could be detected in deeper soil layers of these and other studies, and adsorption/ desorption studies indicated a low mobility in the soil, groundwater contamination through leaching can be excluded. In natural waters, hydrolysis and indirect photolysis occur; in a pond study, the compound dissipated from the water body with DT50 1-4 w. Low vapour pressure and strong adsorption result in low volatilisation into the air.