17804-35-2 Usage
Description
Benomyl, a tan-colored crystalline solid or powder, is a systemic fungicide belonging to the benzimidazole family. It is characterized by a faint acrid odor and is essentially insoluble in water. Benomyl decomposes at high temperatures and is stable under normal storage conditions, but it will decompose to carbendazim in water. Upon decomposition by heat, it produces toxic fumes, including nitrogen oxides.
Uses
Used in Agricultural Industry:
Benomyl is used as a pre-harvest systemic fungicide and as a post-harvest dip for arable and vegetable crops, apples, soft fruit, nuts, mushrooms, lettuce, tomatoes, and turf. It is effective against more than 190 different fungal diseases in stone fruits, pome fruits, tropical and subtropical fruit crops, grapes, fruiting vegetables, cereals, and ornamentals. It is particularly effective against fungal diseases caused by Ascomycetes and Basidiomycetes spp., including leaf spots, blotches, and blights; fruit spots and rots; sooty mold; scabs, bulb, corm, and tuber decays; blossom blights; powdery mildew; certain rusts; and common soil-borne crown and root rots.
Used in Fungicide Applications:
Benomyl is a post-harvest systemic fungicide used to control fungi and mildew on cotton, roses, soft fruits, tomatoes, cucumbers, and other vegetables. It is also used as an ascaricide.
Note: In California, the top five crops for which benomyl is used are pistachios, table and raisin grapes, almonds, strawberries, and wine grapes. However, all uses of benomyl products in the United States were phased out with a deadline of December 31, 2003, and it is not approved for use in EU countries.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
Benomyl is incompatible with strong acids, peroxides and strong oxidizers. Decomposed by strong alkalis. Also decomposes on storage with water .
Hazard
High toxicity by ingestion. Upper respira-
tory tract irritant, male reproductive, testicular, and
embryo/fetal damage. Possible carcinogen.
Health Hazard
Mildly toxic in rodent by ingestion, inhalation, and absorption through skin; large dosescan produce effects of carbamate poisoning;teratogenic and mutagenic effects reported;carcinogenic potential not known; mild skinirritant.LD50 oral (rat): 10,000 mg/kgLD50 skin (mouse): 5600 mg/kgLD50 skin (wild bird): 100 mg/kgBenomyl metabolizes to carbendazim(MBC) and 5-HBC. Animal studies indicatedthat benomyl and its metabolites rapidlyeliminated out within 24 hours of exposure.They do not accumulate in tissues over longterm exposure..
Fire Hazard
Literature sources indicate that Benomyl is nonflammable.
Trade name
ABORTRINE?; AGROCITE?;
ARILATE?; BBC 6597?; BENEX?; BENLAT?[C];
BENLATE?, withdrawn 5/7/01; BENLATE 50?;
BENLATE 50 W?; BENLATE 50WP?; BENOMYL?
50 W; BENOSAN?; D 1991?[C]; F 1991?;
FUNDAZOL?; FUNGICIDE 1991?; FUNGACIDE
D-1991?; FUNGOCHROM?; TARSAN?; TERSAN?;
TERSAN 1991?; UZGN?
Contact allergens
Benomyl is a fungicide, derived from benzimidazole.
Cases of sensitization were reported in horticulturists and
florists. It is however, at most, a weak sensitizer, with
possible false-positive patch reactions, or with crossreactions
after previous exposure to other fungicides.
Safety Profile
Poison by ingestion.
Mildly toxic by inhalation. Experimental
teratogenic and reproductive effects. Human
mutation data reported. A human skin irritant. When heated to decomposition it
emits toxic fumes of NO,. See also
CARB AMATES.
Potential Exposure
Benomyl is used as an agricultural
chemical and pesticide, pharmaceutical, and veterinary drug.
Carcinogenicity
Benomyl was genotoxic, causing chromosome
aberrations in vitro and in vivo, but it does
not directly act with DNA.
Environmental Fate
Biological. Mixed cultures can grow on benomyl as the sole carbon source. It was
proposed that benomyl degraded to butylamine and methyl 2-benzimidazole-carbamate
(MBC), the latter undergoing further degradation to 2-aminobenzimidazole then to carbon
dioxide and other products (Fuchs and de Vries, 1978).Soil. In soil and water, benomyl is transformed to methyl-2-benzimidazole and 2-
aminobenzimidazole (Rhodes and Long, 1974; Ramakrishna et al., 1979; Rajagopal et al.,
1984). Benomyl is easily hydrolyzed in soil to methyl-2-benzimidazole carbamatPlant. On apple foliage treated with a Benlate formulation, benomyl was transformed
to MBC. Benomyl dissipated quickly and the reported half-life on foliage was 3–7 days
(Chiba and Veres, 1981).Chemical/Physical. In aqueous solutions, especially in the presence of acids, benomyl
hydrolyzes to the strongly fungicidal methyl-2-benzimidazolecarbamate (carbendazim)
(Clemons and Sisler, 1969; Peterson and Edgington, 1969; Zbozinek, 1984; Cremlyn,
1991; Worthing and Hance, 1991) and butyl isocyanate (Zbozinek, 1984; Worthing and
Hance, 1991). The latter is unstable in water and decomposes to butylamine and carbon dioxide (Zbozinek, 1984). In highly acidic and alkaline aqueous solutions (pH <1 and pH
>11), benomyl is completely converted to 3-butyl-2,4-dioxo-[1,2-a]-s-triazinobenzimida zole (STB) with smaller quantities of methyl 2-benzimidazolecarbamate (MBC). In addi tion 1-(2-benzimidazolyl)-3-n-butylurea was identified but only under highly alkaline
conditions (Singh and Chiba, 1985).Emits toxic fumes of nitrogen oxides when heated to decomposition (Lewis, 1990).
Metabolic pathway
When benlate is degraded by the singlet oxygen
photoreaction either in methanol or in aqueous
hydrochloric solutions, carbendazim is identified as a
major degradation product with the other nine
degradation products from both reactions, including 2-guanidinobenzimidazole, benzimidazole, and 2,4'-and
2,5'-bibenzimidazoles which are identical to the
photodegradation products of carbendazim by the
singlet oxygen photoreaction in aqueous hydrochloric
acid solution.
Shipping
UN3077 Environmentally hazardous substances,
solid, n.o.s., Hazard class: 9; Labels: 9—Miscellaneous
hazardous material, Technical Name Required.
Degradation
Benomyl (1) was stable under strongly acidic conditions (i.e. 5N HCl;
Singh et al., 1992). Under mildly acidic conditions, benomyl was converted
into carbendazim (MBC, 2) through the loss of n-butyl isocyanate
(3). The mechanism of this reaction involves interaction between the
electron pair at the N-1 position and the proton on the n-butylcarbamoyl
nitrogen. The formation of this hydrogen bond leads to proton abstraction
and the release of 3 (Calmon and Sayag, 1976a). Under alkaline conditions,
the formation of MBC became secondary to the formation of 3-
butyl-2,4-dioxo-s-triazino[1,2-a]benzimidazole(4 ) such that compound 4
was the major degradate at pH 13 (Calmon and Sayag, 1976b; Singh and
Chiba, 1985). The DT50 values of benomyl at 25 °C in pH 5,7 and 9 solutions
were 3.5, 1.5 and <1 hour, respectively (WHO, 1993). The relative
stability of benomyl in strongly acidic solution was attributed to the
protonation of the molecule (Singh et al., 1990).
Carbendazim (2) decomposed under alkaline conditions via the cleavage
of the amide linkage to yield 2-aminobenzimidazole (2-AB, 5)
(Watkins, 1976; Zbozinek, 1984). In pH 9 solution, the hydrolytic DT50 for
MBC was ca. 54 days (WHO, 1993). Under extreme alkaline conditions,
compound 4 was converted into 1-(2-benzimidazolyl)-3-n-butylurea (6)
via the cleavage of the carbamoyl moiety (White et al., 1973). Butyl
isocyanate (3), once formed, hydrolysed rapidly in aqueous solution to
yield n-butylcarbamic acid (7) and n-butylamine (8) (Calmon and Sayag,
1976a). These products are shown in Scheme 1.
Photolysis was not a significant degradation pathway for benomyl in
sterile pH 5 solution (Powley, 1985) under natural sunlight.
Incompatibilities
Incompatible with oxidizers (chlorates,
nitrates, peroxides, permanganates, perchlorates, chlorine,
bromine, fluorine, etc.); contact may cause fires or explosions.
Keep away from alkaline materials, strong bases,
strong acids, oxoacids, epoxides (forms toxic oxides of nitrogen).
Decomposed in water or otherwise moist conditions.
Waste Disposal
In accordance with
40CFR165, follow recommendations for the disposal of
pesticides and pesticide containers. Must be disposed properly
by following package label directions or by contacting
your local or federal environmental control agency, or by
contacting your regional EPA office.
Check Digit Verification of cas no
The CAS Registry Mumber 17804-35-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,7,8,0 and 4 respectively; the second part has 2 digits, 3 and 5 respectively.
Calculate Digit Verification of CAS Registry Number 17804-35:
(7*1)+(6*7)+(5*8)+(4*0)+(3*4)+(2*3)+(1*5)=112
112 % 10 = 2
So 17804-35-2 is a valid CAS Registry Number.
InChI:InChI=1/C14H18N4O3/c1-3-4-9-15-13(19)18-11-8-6-5-7-10(11)16-12(18)17-14(20)21-2/h5-8H,3-4,9H2,1-2H3,(H,15,19)(H,16,17,20)
17804-35-2Relevant articles and documents
SUBSTITUTED SPIROCYCLIC KETOENOLS
-
, (2008/06/13)
The present invention relates to novel substituted spirocyclic ketoenols of the formula (I) in which W, X, Y, Z, A, B, D and G are as defined in the disclosure, to a plurality of processes for their preparation and to their use as pesticides, microbicides and herbicides.
Use of oxabicyclo[2.2.1]heptane derivatives as pesticidal agents
-
, (2008/06/13)
7-oxabicyclo[2.2.1]heptane derivatives of formula (I) in which X, R1, R2, R3 and R4 have the meanings set forth in the specification, are very suitable for controlling undesired microorganisms and animal pests. New 7-oxabicyclo[2.2.1]heptane derivatives of formula (Ia) in which X, R1, R2, R3 and R14 have the meanings set forth in the specification, and a process for the preparation of the new compounds.
