Captan

Last updated
Captan
Captan Structural Formula V.1.svg
Captan-from-xtal-1981-CM-3D-balls.png
Names
IUPAC name
(3aR,7aS)-2-[(Trichloromethyl)sulfanyl]-3a,4,7,7a-tetrahydro-1H-isoindole-1,3(2H)-dione
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.004.626 OOjs UI icon edit-ltr-progressive.svg
KEGG
PubChem CID
UNII
  • InChI=1S/C9H8Cl3NO2S/c10-9(11,12)16-13-7(14)5-3-1-2-4-6(5)8(13)15/h1-2,5-6H,3-4H2 Yes check.svgY
    Key: LDVVMCZRFWMZSG-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C17H19ClN2O3/c18-13-7-3-4-8-14(13)19-15(21)9-10-20-16(22)11-5-1-2-6-12(11)17(20)23/h3-4,7-8,11-12H,1-2,5-6,9-10H2,(H,19,21)/t11-,12-/m1/s1
    Key: PIBUBEBGJVBNLY-VXGBXAGGBJ
  • InChI=1/C9H8Cl3NO2S/c10-9(11,12)16-13-7(14)5-3-1-2-4-6(5)8(13)15/h1-2,5-6H,3-4H2
    Key: LDVVMCZRFWMZSG-UHFFFAOYAB
  • C1C=CC[C@H]2[C@@H]1C(=O)N(C2=O)SC(Cl)(Cl)Cl
  • ClC(Cl)(Cl)SN1C(=O)C2C/C=C\CC2C1=O
Properties
C9H8Cl3NO2S
Molar mass 300.58 g·mol−1
Appearancewhite solid; yellow powder (commercial) [1]
Density 1.74 g/cm3 [2]
Melting point 178 °C (352 °F; 451 K) (decomposes)
Boiling point N/A
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
combustible, potential occupational carcinogen [1]
NIOSH (US health exposure limits):
PEL (Permissible)
none [1]
REL (Recommended)
Ca TWA 5 mg/m3 [1]
IDLH (Immediate danger)
N.D. [1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Captan is a general use pesticide (GUP) that belongs to the phthalimide class of fungicides. It is a white solid, although commercial samples appear yellow or brownish. [3]

Contents

Applications

Although it can be applied on its own, Captan is often added as a component of other pesticide mixtures. It is used to control diseases on a number of fruits [4] and vegetables as well as ornamental plants. It also improves the outward appearance of many fruits, making them brighter and healthier-looking. Captan is utilized by both home and agricultural growers and is often applied during apple production. It is also active against certain oomycetes, such as Pythium, making it useful for controlling damping off. [5]

Biodegradation

The compound biodegrades with half life of less than 1 day in soil. [3]

Potential health effects

Captan was previously cited as Group B2, a probable human carcinogen by the US Environmental Protection Agency (EPA), [6] but was reclassified in 2004. Since the mode of action has been established as a proliferative response (in mice only) after intestinal villi are disrupted, captan has been deemed not likely to cause tumors at doses that do not irritate the intestine. The EPA now states, "The new cancer classification considers captan to be a potential carcinogen at prolonged high doses that cause cytotoxicity and regenerative cell hyperplasia. These high doses of captan are many orders of magnitude above those likely to be consumed in the diet, or encountered by individuals in occupational or residential settings. Therefore, captan is not likely to be a human carcinogen nor pose cancer risks of concern when used in accordance with approved product labels. [7] A similar reclassification has been made for folpet, a structurally related fungicide, which shares a common mechanism of toxicity. [8] [9] A key finding for captan (and folpet) is these fungicides are not mutagenic in the animal (in vivo). [10] [11] [12]

Production

It is the product of the reaction trichloromethylsulfenyl chloride with sodium salt of tetrahydrophthalamide. [3]

Related Research Articles

<span class="mw-page-title-main">1,4-Dichlorobenzene</span> Chemical compound

1,4-Dichlorobenzene (1,4-DCB, p-DCB, or para-dichlorobenzene, sometimes abbreviated as PDCB or para) is an organic compound with the formula C6H4Cl2. This colorless solid has a strong odor. The molecule consists of a benzene ring with two chlorine atoms (replacing hydrogen atoms) on opposing sites of the ring.

Bromomethane, commonly known as methyl bromide, is an organobromine compound with formula CH3Br. This colorless, odorless, nonflammable gas is produced both industrially and biologically. It has a tetrahedral shape and it is a recognized ozone-depleting chemical. It was used extensively as a pesticide until being phased out by most countries in the early 2000s.

Chlordane, or chlordan, is an organochlorine compound that was used as a pesticide. It is a white solid. In the United States, chlordane was used for termite-treatment of approximately 30 million homes until it was banned in 1988. Chlordane was banned 10 years earlier for food crops like corn and citrus, and on lawns and domestic gardens.

<span class="mw-page-title-main">Piperonyl butoxide</span> Chemical compound

Piperonyl butoxide (PBO) is a pale yellow to light brown liquid organic compound used as a synergist component of pesticide formulations. That is, despite having no pesticidal activity of its own, it enhances the potency of certain pesticides such as carbamates, pyrethrins, pyrethroids, and rotenone. It is a semisynthetic derivative of safrole.

<span class="mw-page-title-main">Lindane</span> Organochlorine chemical and an isomer of hexachlorocyclohexane

Lindane, also known as gamma-hexachlorocyclohexane (γ-HCH), gammaxene, Gammallin and benzene hexachloride (BHC), is an organochlorine chemical and an isomer of hexachlorocyclohexane that has been used both as an agricultural insecticide and as a pharmaceutical treatment for lice and scabies.

<span class="mw-page-title-main">Carbofuran</span> Toxic carbamate pesticide

Carbofuran is a carbamate pesticide, widely used around the world to control insects on a wide variety of field crops, including potatoes, corn and soybeans. It is a systemic insecticide, which means that the plant absorbs it through the roots, and from there the plant distributes it throughout its organs where insecticidal concentrations are attained. Carbofuran also has contact activity against pests. It is one of the most toxic pesticides still in use.

A reference dose is the United States Environmental Protection Agency's maximum acceptable oral dose of a toxic substance, "below which no adverse noncancer health effects should result from a lifetime of exposure". Reference doses have been most commonly determined for pesticides. The EPA defines an oral reference dose as:

[A]n estimate, with uncertainty spanning perhaps an order of magnitude, of a daily oral exposure to the human population that is likely to be without an appreciable risk of deleterious effects during a lifetime.

<span class="mw-page-title-main">Carbaryl</span> Chemical compound

Carbaryl is a chemical in the carbamate family used chiefly as an insecticide. It is a white crystalline solid previously sold under the brand name Sevin, which was a trademark of the Bayer Company. The Sevin trademark has since been acquired by GardenTech, which has eliminated carbaryl from most Sevin formulations. Union Carbide discovered carbaryl and introduced it commercially in 1958. Bayer purchased Aventis CropScience in 2002, a company that included Union Carbide pesticide operations. Carbaryl was the third-most-used insecticide in the United States for home gardens, commercial agriculture, and forestry and rangeland protection. As a veterinary drug, it is known as carbaril (INN).

<span class="mw-page-title-main">Malathion</span> Chemical compound

Malathion is an organophosphate insecticide which acts as an acetylcholinesterase inhibitor. In the USSR, it was known as carbophos, in New Zealand and Australia as maldison and in South Africa as mercaptothion.

<span class="mw-page-title-main">Atrazine</span> Herbicide

Atrazine is a chlorinated herbicide of the triazine class. It is used to prevent pre-emergence broadleaf weeds in crops such as maize (corn), soybean and sugarcane and on turf, such as golf courses and residential lawns. Atrazine's primary manufacturer is Syngenta and it is one of the most widely used herbicides in the United States, Canadian, and Australian agriculture. Its use was banned in the European Union in 2004, when the EU found groundwater levels exceeding the limits set by regulators, and Syngenta could not show that this could be prevented nor that these levels were safe.

<span class="mw-page-title-main">Benomyl</span> Chemical compound

Benomyl is a fungicide introduced in 1968 by DuPont. It is a systemic benzimidazole fungicide that is selectively toxic to microorganisms and invertebrates, especially earthworms, but nontoxic toward mammals.

<span class="mw-page-title-main">Vinclozolin</span> Fungicide used on fruits and vegetables

Vinclozolin is a common dicarboximide fungicide used to control diseases, such as blights, rots and molds in vineyards, and on fruits and vegetables such as raspberries, lettuce, kiwi, snap beans, and onions. It is also used on turf on golf courses. Two common fungi that vinclozolin is used to protect crops against are Botrytis cinerea and Sclerotinia sclerotiorum. First registered in 1981, vinclozolin is widely used but its overall application has declined. As a pesticide, vinclozolin is regulated by the United States Environmental Protection Agency. In addition to these restrictions within the United States, as of 2006 the use of this pesticide was banned in several countries, including Denmark, Finland, Norway, and Sweden. It has gone through a series of tests and regulations in order to evaluate the risks and hazards to the environment and animals. Among the research, a main finding is that vinclozolin has been shown to be an endocrine disruptor with antiandrogenic effects.

Iodomethane, also called methyl iodide, and commonly abbreviated "MeI", is the chemical compound with the formula CH3I. It is a dense, colorless, volatile liquid. In terms of chemical structure, it is related to methane by replacement of one hydrogen atom by an atom of iodine. It is naturally emitted by rice plantations in small amounts. It is also produced in vast quantities estimated to be greater than 214,000 tons annually by algae and kelp in the world's temperate oceans, and in lesser amounts on land by terrestrial fungi and bacteria. It is used in organic synthesis as a source of methyl groups.

<span class="mw-page-title-main">Chlorothalonil</span> Fungicide

Chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile) is an organic compound mainly used as a broad spectrum, nonsystemic fungicide, with other uses as a wood protectant, pesticide, acaricide, and to control mold, mildew, bacteria, algae. Chlorothalonil-containing products are sold under the names Bravo, Echo, and Daconil. It was first registered for use in the US in 1966. In 1997, the most recent year for which data are available, it was the third most used fungicide in the US, behind only sulfur and copper, with 12 million pounds used in agriculture that year. Including nonagricultural uses, the United States Environmental Protection Agency (EPA) estimates, on average, almost 15 million lb (6.8 million kg) were used annually from 1990 to 1996.

<span class="mw-page-title-main">1,3-Dichloropropene</span> Chemical compound

1,3-Dichloropropene, sold under diverse trade names, is an organochlorine compound with the formula C3H4Cl2. It is a colorless liquid with a sweet smell. It is feebly soluble in water and evaporates easily. It is used mainly in farming as a pesticide, specifically as a preplant fumigant and nematicide. It is widely used in the US and other countries, but is banned in 34 countries.

<span class="mw-page-title-main">Pesticides in the United States</span> Review of the topic

Pesticides in the United States are used predominantly by the agricultural sector, but approximately a quarter of them are used in houses, yards, parks, golf courses, and swimming pools.

<span class="mw-page-title-main">Enilconazole</span> Chemical compound

Enilconazole is a fungicide widely used in agriculture, particularly in the growing of citrus fruits. Trade names include Freshgard, Fungaflor, and Nuzone.

<span class="mw-page-title-main">Thiram</span> Chemical compound

Thiram is the simplest thiuram disulfide and the oxidized dimer of dimethyldithiocarbamate. It is used as a fungicide, ectoparasiticide to prevent fungal diseases in seed and crops and similarly as an animal repellent to protect fruit trees and ornamentals from damage by rabbits, rodents and deer. It is effective against Stem gall of coriander, damping off, smut of millet, neck rot of onion, etc. Thiram has been used in the treatment of human scabies, as a sun screen and as a bactericide applied directly to the skin or incorporated into soap.

<span class="mw-page-title-main">Captafol</span> Chemical compound

Captafol is a fungicide. It is used to control almost all fungal diseases of plants except powdery mildews. It is believed to be a human carcinogen, and production for use as a fungicide in the United States stopped in 1987. Its continued use from existing stocks was allowed, but in 1999 the Environmental Protection Agency banned its use on all crops except onions, potatoes, and tomatoes. In 2006 even these exceptions were disallowed, so currently its use on all crops is banned in the United States. Several other countries have followed suit since 2000, and as of 2010, no countries are known to allow the use of captafol on food crops. Currently, the National Institute for Occupational Safety and Health established a recommended exposure limit of 0.1 mg/m3 for dermal exposures.

<span class="mw-page-title-main">Bentazon</span> Chemical compound

Bentazon is a chemical manufactured by BASF Chemicals for use in herbicides. It is categorized under the thiadiazine group of chemicals. Sodium bentazon is available commercially and appears slightly brown in colour.

References

  1. 1 2 3 4 5 NIOSH Pocket Guide to Chemical Hazards. "#0099". National Institute for Occupational Safety and Health (NIOSH).
  2. Captan (Icsc)
  3. 1 2 3 Franz Müller; Peter Ackermann; Paul Margot (2012). "Fungicides, Agricultural, 2. Individual Fungicides". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.o12_o06. ISBN   978-3527306732.
  4. Dowling, Madeline; Peres, Natalia; Villani, Sara; Schnabel, Guido (2020). "Managing Colletotrichum on Fruit Crops: A "Complex" Challenge". Plant Disease. 104 (9): 2301–2316. doi: 10.1094/PDIS-11-19-2378-FE . ISSN   0191-2917. PMID   32689886. S2CID   219479598.
  5. Review of Fungicides for Control of Phytophthora and Pythium Diseases on Potted Ornamentals
  6. EPA Captan Reregistration Eligibility Decision Facts Archived October 6, 2006, at the Wayback Machine
  7. US EPA. 2004. Captan: Cancer Reclassification; Amendment of Reregistration Eligibility Decision; Notice of Availability. Federal Register 69: 68357-68360
  8. Bernard, B. K., and Gordon, E. B. 2000. An evaluation of the common mechanism approach to the Food Quality Protection Act: Captan and four related fungicides, a practical example. Int J Toxicol 19: (1): 43-61.
  9. Kidwell, J. (2010). Cancer Assessment Document. Second Evaluation of the Carcinogenic Potential of Folpet. PC Code 081601. Cancer Assessment Review Committee, Health Effects Division, Office of Pesticide Programs, U.S. Environmental Protection Agency, USA. Folpet Cancer Assessment Document Final. Memorandum to Abdallah Khasawinah, RAB IV, Health Effect Division (7505P) and Tony Kish, Product Manager, Team 22, Fungicide Branch, Registration Division (7505P), through Mary Manibusan and Jess Rowland, Co-Chairs Cancer Assessment Review Committee, Health Effects Division (7509P), 53 Pages, October 13, 2010.
  10. Cohen, S. M., Gordon, E. B., Singh, P., Arce, G. T., and Nyska, A. 2010. Carcinogenic Mode of Action of Folpet in Mice and Evaluation of Its Relevance to Humans. Critical Reviews in Toxicology 40: (6): 531-545.
  11. Arce, G. T., Gordon, E. B., Cohen, S. M., and Singh, P. 2010. Genetic Toxicology of Folpet and Captan. Critical Reviews in Toxicology 40: (6): 546-574.
  12. Gordon, E. B. 2010b. Captan and Folpet. In: R. Krieger, ed. Hayes Handbook of Pesticide Toxicology pp. 1915-1949. Elsevier, New York