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| | CAPTAFOL Basic information |
| Product Name: | CAPTAFOL | | Synonyms: | (Tetrachloroethylthio)tetrahydrophthalimide;1,2,3,6-tetrahydro-n-(1,1,2,2-tetrachloroethylthio)phthalimide;1H-Isoindole-1,3(2H)-dione, 3a,4,7,7a-tetrahydro-2-[(1,1,2,2-tetrachloroethyl)thio]-;1h-isoindole-1,3(2h)-dione,3a,4,7,7a-tetrahydro-2-((1,1,2,2-tetrachloroethyl;1-h-isoindole-1,3(2h)-dione,3a,4,7,7a-tetrahydro-2-((1,1,2,2-tetrachloroethyl);2-[(1,1,2,2-Tetrachloroethyl)sulfanyl]-3a,4,7,7a-tetrahydro-1H-isoindole-1,3(2H)-dione;3a,4,7,7a-tetrahydro-2-((1,1,2,2-tetrachloroethyl)thio)-1h-isoindole-1,3(2h)-d;3a,4,7,7a-tetrahydro-2-(1,1,2,2-tetrachloroethyl)thio-1h-isoindole-1,3(2h)-dio | | CAS: | 2425-06-1 | | MF: | C10H9Cl4NO2S | | MW: | 349.06 | | EINECS: | 219-363-3 | | Product Categories: | Alphabetic;CA - CG;Alpha sort;C;CA - CGPesticides;CAlphabetic;DicarboximidesMethod Specific;Fungicides;Oeko-Tex Standard 100;Pesticides;Pesticides&Metabolites | | Mol File: | 2425-06-1.mol |  |
| | CAPTAFOL Chemical Properties |
| Melting point | 160-161° | | Boiling point | 365.7±52.0 °C(Predicted) | | density | 1.4682 (rough estimate) | | vapor pressure | 1.1 x 10-6 Pa (20 °C) | | refractive index | 1.6000 (estimate) | | Fp | >100 °C | | storage temp. | 0-6°C | | solubility | Chloroform (Sparingly), Dichloromethane (Very Slightly), Methanol (Slightly) | | form | Solid | | pka | -2.67±0.20(Predicted) | | Water Solubility | 1.4 mg l-1 (20 °C) | | color | White to Off-White | | Merck | 13,1777 | | IARC | 2A (Vol. 53) 1991 | | EPA Substance Registry System | Captafol (2425-06-1) |
| | CAPTAFOL Usage And Synthesis |
| Description | Captafol appears as white, colourless to pale yellow, or tan (technical-grade) crystals or as
a crystalline solid or powder, with a slight characteristic pungent odour. It is practically
insoluble in water but is soluble or slightly soluble in most organic solvents. Captafol
reacts with bases, acids, acid vapours, and strong oxidisers. Captafol is a broad-spectrum
nonsystemic fungicide that is categorised as a phthalimide fungicide based on its tetrahydrophthalimide
chemical ring structure (other phthalimide fungicides include captan
and folpet). It hydrolyses slowly in aqueous emulsions or suspensions but rapidly
in acidic and basic aqueous alkaline media. Captafol will not burn, but when heated to
decomposition, it emits toxic fumes, including nitrogen oxides, sulphur oxides, phosgene,
and chlorine.
Captafol is effective for the control of almost all fungal diseases of plants except powdery
mildews and is widely used outside the United States for the control foliage and
fruit disease on apples, citrus, tomato, cranberry, potato, coffee, pineapple, peanut, onion,
stone fruit, cucumber, blueberry, prune, watermelon, sweet corn, wheat, barley, oilseed
rape, leek, and strawberry. It is also used as a seed protectant in cotton, peanuts, and rice.
Captafol is also used in the lumber and timber industries to reduce losses from wood rot
fungi in logs and wood products. Formulations of captafol include dusts, flowables, wettables,
water dispersibles, and aqueous suspensions. Mixed formulations include (captafol +)
triadimefon, ethirimol, folpet, halacrinate, propiconazole, and pyrazophos. Captafol is
compatible with most plant-protection products, with the exception of alkaline preparations
and formulating material. | | Chemical Properties | Captafol is a white crystalline solid.
| | Chemical Properties | yellow to off-white powder | | Uses | Agricultural fungicide, especially for potatoes. | | Uses | Captafol is a pesticide, belonging to thiophtalimide
group. Occupational contact dermatitis was reported
in an agricultural worker who had multiple sensitizations. | | Uses | Captafol is used to control a wide range of fungal diseases on
many crops. | | Definition | ChEBI: A dicarboximide that captan in which the trichloromethyl group is replaced by a 1,1,2,2-tetrachloroethyl group. A broad-spectrum fungicide used to control diseases in fruit and potatoes, it is no longer approved for use in the European Community. | | General Description | White crystalline solid with a slight, but pungent odor. Mp: 162°C. Practically insoluble in water. Only slightly soluble in organic solvents. Technical CAPTAFOL is a wettable light tan powder that is used as a fungicide. Inhaled dust irritates the respiratory tract. Irritates skin and damages eyes. Acute oral toxicity in humans is low. Not persistent in the environment (decomposes with a half-life of 11 days in the soil). Highly toxic to fish and other aquatic organisms. | | Reactivity Profile | CAPTAFOL is non-flammable but, on heating, may decompose to generate toxic fumes, such as sulfur oxides, hydrogen sulfide, hydrochloric acid, and phosgene. Stable at room temperature when dry but readily hydrolysed, especially in an alkaline environment. CAPTAFOL and mixtures containing high concentrations of CAPTAFOL may react violently with alkali. Incompatible with acids, acid chlorides, acid anhydrides, and strong oxidizing agents. Sulfhydryl compounds such as glutathione and cysteine cause a rapid chemical decomposition. | | Hazard | Absorbed by skin. Probable carcinogen. | | Agricultural Uses | Fungicide: Captafol is a General Use Pesticide and used for the control of practically all forms of fungal diseases except powdery mildew. It is also used as a seed protectorant on cotton, rice and peanut crops. Not registered for use in the U.S. or in EU countries. There are 20 global suppliers. | | Trade name | CAPTATOL®; CAPTOFOL®; CRISFOLATAN®; DIFOLATAN®[C]; DIFOCAP®[C]; DIFOSAN®; FOLCID®; HAIPEN®; KENOFOL®; MERPAFOL®; ORTHO® 5865[C]; PILLARTAN®; SANSEAL®; SANSPOR®; SANTAR-SM®; SULFONIMIDE®; SULPHEIMIDE® | | Contact allergens | Captafol is a pesticide, belonging to thiophthalimide
group. Occupational contact dermatitis was reported in
an agricultural worker who had multiple sensitizations | | Safety Profile | Confirmed carcinogen
with experimental carcinogenic data. Poison
by intraperitoneal route. Moderately toxic by
ingestion. An experimental teratogen. Other
experimental reproductive effects. Mutation
data reported. A fungicide. When heated to
decomposition it emits very toxic fumes of
Cl-, NO,, and SOx | | Potential Exposure | Captafol is a thiophthalimide fungicide. Those engaged in the manufacture, formulation, and
application of this fungicide. Captafol is not currently registered for use on field crops or stored produce in the
United States. | | Carcinogenicity | Captafol is reasonably anticipated to be a human carcinogen based on sufficient evidence of carcinogenicity from studies in experimental animals and supporting data on mechanisms of carcinogenesis. | | Environmental Fate | The primary toxicity following captafol exposure probably
occurs through a hypersensitivity mechanism. Most experiments
suggest captafol to be DNA active. | | Metabolic pathway | Captafol contains an unstable tetrachloroethylthio (sulfenyl) moiety that
has been shown to undergo rapid hydrolytic and metabolic degradation
to tetrahydrophthalimide (2). By analogy with captan, presumably the
tetrachloroethylthio moiety can be transferred to the sulfur atoms of
thiols such as cysteine and glutathone. Thus in the presence of thiols
such as glutathione, captafol is probably cleaved at the N-S bond to
form thiophosgene (3) and other gaseous products such as hydrogen
sulfide, hydrogen chloride and carbonyl sulfide. Thiophosgene is rapidly
hydrolysed by water. The tetrachloroethylthio group and thiophosgene
are believed to be intermediates in the formation of thiazolidine-2-
thione-6carboxylic acid (4) which is an addition product with cysteine. A
thiazolidine derivative of glutathione is also formed (5). Biotransformation
of captafol in mammals generates primarily thiophosgene (3)
and tetrahydrophthalimide (2). Tetrahydrophthalimide (2) and various
of its derivatives are excreted in the urine. There were no reports of
2-thiazolidinethione-4-carboxylic acid (4) in the urine. | | Shipping | UN2811 Toxic solids, organic, n.o.s., Hazard
Class: 6.1; Labels: 6.1-Poisonous materials, Technical
Name Required. UN 2773 Phthalimide derivative pesticides, solid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous
materials, Technical Name Required. | | Degradation | Captafol is hydrolysed rapidly in acidic and alkaline conditions. It
decomposes slowly at its melting point of 161 °C (PM). Captafol is
decomposed by base-catalysed hydrolysis with half-lives of 77.8, 6.54 and
0.72 hours at pH 3,7 and 8, respectively (Kim et al., 1997)
In a study of aqueous photodegradation, a solution (MeCN/H2O 9:l)
of unlabelled captafol (10 g l-1) was exposed to UV light for 4 days. The
reaction tube was encircled by low pressure Hg lamps giving more than
85% of total radiation at 253.7 nm. Pure nitrogen was bubbled through the
solutions. Photo-oxidation studies were done similarly except that oxygen
was bubbled through the solution. In further experiments, irradiation was
by visible light from a tungsten lamp and again oxygen was bubbled
through the solution. The outlet gases from the UV study were trapped in
sodium hydroxide solution and analysed by GC-MS. The main photoproduct
was usually tetrahydrophthalimide (2). Analysis was by chromatography
and IR and NMR spectroscopy. Photolysis under nitrogen gave
2 in 72% yield with elemental sulfur and HCl as the only products other
than some parent captafol. Photooxidation of captafol gave tetrahydrophthalimide
(2) in 78% yield together with sulfur dioxide, carbon dioxide,
hydrogen chloride and some unreacted captafol. Oxidation of captafol
in the presence of visible light together with Rose Bengal as a photosensitiser
also gave a high yield of tetrahydrophthalimide (2) and the
other products obtained from photo-oxidation. Although the mechanisms
of reaction were not studied, it is possible that sulfoxidised intermediates
could be involved in reactions with singlet oxygen. It was surprising that the cyclohexene moiety did not react with singlet oxygen and that
products of ring oxidation were not observed (Crank and Mursyidi, 1992). | | Toxicity evaluation | Captafol is not persistent in the environment. Captafol is stable
under ordinary environmental conditions and rapidly degrades
in soil, the rate of degradation being a function of soil type and
pesticide concentration. It does not leach from basic soils and is
unlikely to contaminate groundwater. Captafol sprayed on
most crops has a half-life of less than 5 days. Captafol and/or its
metabolites and degradation products are readily absorbed by
roots and shoots of plants. If released to air, an extrapolated
vapor pressure of 8.27×10-9 mm Hg at 25°C indicates
captafol will exist solely in the particulate phase in the ambient
atmosphere. Particulate-phase captafol will be removed from
the atmosphere by wet and dry deposition. If released to soil,
captafol is expected to have slight mobility based on Koc values
of 2073 and 2120. Volatilization from moist soil surfaces is not
expected to be an important fate process based on a Henry’s
Law constant of 2.7×10-9 atm-cu m mol-1. In a laboratory
setting, the biodegradation half-life of captafol in three soils
was found in the range of 23–55 days. The overall half-life of
captafol in soil is about 11 days, independent of soil type or
initial concentration. If released into water, captafol is expected
to adsorb to suspended solids and sediment based on the Koc.
Volatilization from water surfaces is not expected to be an
important fate process based on this compound’s estimated
Henry’s Law constant. An estimated bioconcentration factor of
170 suggests the potential for bioconcentration in aquatic
organisms is high, provided the compound is not altered
physically or chemically after being released to the environment. The half-lives for the hydrolysis of Difolatan at
pH 3.0, 7.0, and 8.0 were 77.8, 6.54, and 0.72 h, respectively.
Hydrolysis is likely to be the predominant pathway of degradation
in the aquatic environment. | | Incompatibilities | Reacts violently with bases, causing fire
and explosion hazard. Not compatible with strong acids or
acid vapor, oxidizers. Strong alkaline conditions contribute
to instability. Attacks some metals. | | Waste Disposal | Hydrolysis. |
| | CAPTAFOL Preparation Products And Raw materials |
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