133-06-2

solid

Fungicide, often added to pesticide mixtures used to control diseases among fruits, vegetables.

ChEBI: A dicarboximide that is 3a,4,7,7a-tetrahydrophthalimide in which the hydrogen attached to the nitrogen is replaced by a trichloromethyl group. A non-systemic fungicide introduced in the 1950s, it is widely used for the control of fungal diseases in fruits, vegetables, and ornamental crops.

Fungicide; bacteriostat in soap.

CAPTAN(133-06-2) is a white solid dissolved in a liquid carrier. CAPTAN(133-06-2) is a water emulsifiable liquid. CAPTAN(133-06-2) can cause illness by inhalation, skin absorption and/or ingestion. The primary hazard of this material is that CAPTAN(133-06-2) poses a threat to the environment. In case of release immediate steps should be taken to limit its spread to the environment. Since CAPTAN(133-06-2) is a liquid CAPTAN(133-06-2) can easily penetrate the soil to contaminate groundwater. CAPTAN(133-06-2) is used as a fungicide.

CAPTAN decomposes at or near the melting point. This chemical is incompatible with strong alkaline and oxidizing materials, sulfur and (sulfur + moisture).

Slowly hydrolyzed in aqueous neutral and acidic media. Rapidly hydrolyzed in alkaline media. Insoluble in water.

A questionable carcinogen. A skin irritant. Avoid inhalation of dust or spray mist. Avoid con- tamination of feed and foodstuffs.

Vapor irritates eyes. Ingestion causes depression, lachrymation, labored respiration, diarrhea.

Captan is a thiophthalimide compound used as an agricultural fungicide for field crops and storage of produce and also as a preservative in cosmetics; an overthe-counter-drug.

Special Hazards of Combustion Products: Irritating and toxic gases are produced in a fire; they may include sulfur dioxide, hydrogen chloride, phosgene, and oxides of nitrogen.

If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit.

UN2773 Phthalimide derivative pesticides, solid, toxic, Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required. UN2811 Toxic solids, organic, n.o.s., Hazard Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name Required.

Incompatible with tetraethyl pyrophosphate, parathion. Keep away from strong alkaline materials(e.g., hydrated lime) as captan may become unstable. May react with water releasing hydrogen chloride gas. Corrosive to metals in the presence of moisture.

Captane is a pesticide belonging to the thiophtalimide group, mainly affecting agricultural workers. As a sensitizer and photosensitizer, it can induce contact urticaria. Its is used as a fungicide and a bacteriostatic agent in cosmetics and toiletries, particularily in shampoos. Cases of contact dermatitis were reoprted in painters, polishers and varnishers.

Captan decomposes fairly readily in alkaline media (pH ＞8). It is hydrolytically stable at neutral or acid pH but decomposes when heated alone at its freezing/melting point. Alkaline hydrolysis is recommended

Notclassified

Fungicide: Most uses of captan on food crops in the United States have been canceled since 1989. It is still used in apple production, almonds and strawberries. It is often applied to packing and shipping boxes for fruits and vegetables. Captan is rapidly degraded in natural soil by chemical as well as biologic means (estimated half-life, days to weeks). It is also used as a preservative for awnings, draperies and leather, as a root dip and seed treatment. It is also added to paints, wallpaper paste, plastic and leather goods. There are over 320 federally registered pesticide products that contain captan.

AACAPTAN®; AGROSOL S®[C]; AGROX® 2-WAY and 3-WAY[C]; AMERCIDE®; APRON®[C]; BEISTERGARD®; BANGTON®; BEAN SEED PROTECTANT®; CAPTANCAPTENEET® 26,538; CAPTAF®; CAPTAF®; CAPTAN® 50 W; CAPTAN SC®; CAPTEX®; CRIPTAN®; ESSO® FUNGICIDE 406; FLIT® 406; FUNGUS BAN® TYPE II; FUNGICIDE 406®; GLYODEX® 37-22; GRANOX PFM®; GUSTAFSON CAPTAN 30-DD; HEXACAP®; ISOTOX SEED TREATER® “D” and “F”; KAPTAN®; MALIPUR®; MERPAN®; MICRO-CHECK® 12; MIOSTAT®; NERACID®; ORTHOCIDE®; OSOCIDE®; POTATO SEED PIECE PROTECTANT®; SR 406®; STAUFFER CAPTAN®; TRIMEGOL®; VANICIDE®; VANICIDE® P-75; VANICIDE® 89; VANICIDE® 89RE; VANGARD® K; VANGUARD® K; VONDCAPTAN®

Biological. In water, captan reacted with the fungicide L-cysteine forming a compound with an absorption maximum of 272 μm which was identified as 2-thiazolidinethione-4- carboxylic acid. In addition, tetrahydrophthalimide also formed (Lukens and Sisler, 1958).
Soil. The half-lives of captan in soil ranged from 3.5 days (pH 6.4, moisture content 17.5%) to >50 days (pH 6.2, moisture content 1.6%) (Burchfield, 1959). The half-lives of captan in a sandy loam, clay loam and an organic amended soil under non-sterile conditions were 10–354, 3.4–587 and 7.0–213 days, respectively, while under sterile conditions the half-lives were 9.4–373, 2.8–303 and 4.3–191 days, respectively (Schoen and Winterlin, 1987).
Chemical/Physical. Captan undergoes hydrolysis under neutral or alkaline conditions yielding 4-cyclohexene-1,2-dicarboximide, carbon dioxide, hydrogen chloride and sulfur (Wolfe et al., 1976a). The estimated hydrolysis half-life of captan in a phosphate buffer solution at pH 7.07 and 28–29°C is 2.96 hours. Between the pH range 2 to 6, the estimated hydrolysis half-life is 10.70 hours (Wolfe et al., 1976a). Worthing and Hance (1991)reported hydrolysis half-lives of 8.3–32.4 hours and <2 minutes at pH values 7 and 10, respectively.
Decomposes at or near the melting point (Hartley and Kidd, 1987).

Captan contains an unstable trichloromethylthio (sulfenyl) moiety that has been shown to undergo rapid hydrolytic and metabolic degradation to tetrahydrophthalimide (2).
Studies of the decomposition of [³⁵S]captanw ith conidia of Neurospora crassa (Richmond and Somers, 1968) showed that the trichloromethythio moiety can be transferred to the sulfur atoms of thiols such as cysteine and glutathione (Richmond and Somers, 1966). Thus, in the presence of thiols such as glutathione, captan is cleaved at the N-S bond to form thiophosgene (3) and other gaseous products such as hydrogen sulfide, hydrogen chloride and carbonyl sulfide (see Scheme 2). Thiophosgene is rapidly hydrolysed by water. The trichlormethythio group and thiophosgene are believed to be intermediates in the formation of thiazolidine-2- thione-4-carboxylic acid (4) which is an addition product with cysteine. A thiazolidine derivative of glutathione is also formed (5). Biotransformation of captan in mammals generates primarily thiophosgene (3) and tetrahydrophthalimide (2). Tetrahydrophthalimide (2) and various of its hydroxylated derivatives are excreted in the urine. The thiophosgeneglutathione adduct (5) subsequently degrades and is eventually excreted in the urine as 2-thiazolidinethione-4-carboxylic acid (4).

Color Code—Blue: Health Hazard/Poison: Storein a secure poison location. Prior to working with captanyou should be trained on its proper handling and storage.Store in tightly closed containers in a cool, well-ventilatedarea away from water, heat, and incompatible materials.Metal containers involving the transfer of this chemicalshould be grounded and bonded. Where possible, automatically pump liquid from drums or other storage containers toprocess containers. Drums must be equipped with selfclosing valves, pressure vacuum bungs, and flame arresters.Use only nonsparking tools and equipment, especially whenopening and closing containers of this chemical. Sources ofignition, such as smoking and open flames, are prohibitedwhere this chemical is used, handled, or stored in a mannerthat could create a potential fire or explosion hazard. A regulated, marked area should be established where this chemical is handled, used, or stored in compliance with OSHAStandard 1910.1045.

The half-life of captan is 1–10 days in a soil environment, and hours to days in water depending on acidities and temperatures. Captan is not mobile in soil but can significantly evaporate from the soil surface. It is quickly degraded in neutral water.