Captan is a general use pesticide (GUP) that belongs to the

phthalimide Phthalimide is the organic compound with the formula C6H4(CO)2NH. It is the imide derivative of phthalic anhydride. It is a Sublimation (phase transition), sublimable white solid that is slightly soluble in water but more so upon addition of ba ...

class of

fungicide Fungicides are biocidal chemical compounds or biological organisms used to kill parasitic fungi or their spores. A fungistatic inhibits their growth. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality, ...

s. It is a white solid, although commercial samples appear yellow or brownish.

Applications

Although it can be applied on its own, Captan is often added as a component of other

pesticide Pesticides are substances that are meant to control pests. This includes herbicide, insecticide, nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, microbicide, fungicide, and lampri ...

mixtures. It is used to control diseases on a number of

fruits In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particula ...

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 Oomycota forms a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms, called oomycetes (). They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction of an oospore is the result ...

, such as Pythium, making it useful for controlling damping off.

Biodegradation

The compound biodegrades with halflife of less than 1 day in soil.

Potential health effects

Captan was previously cited as Group B2, a probable human carcinogen by the US

Environmental Protection Agency A biophysical environment is a biotic and abiotic surrounding of an organism or population, and consequently includes the factors that have an influence in their survival, development, and evolution. A biophysical environment can vary in scale f ...

(EPA), but was reclassified in 2004. Since the mode of action has been established as a proliferative response (in

mice A mouse ( : mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus' ...

only) after intestinal villi are disrupted, captan has been deemed not likely to cause tumors at doses that do not irritate the

intestine The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans ...

. The EPA now states, "The new cancer classification considers captan to be a potential carcinogen at prolonged high doses that cause

cytotoxicity Cytotoxicity is the quality of being toxic to cells. Examples of toxic agents are an immune cell or some types of venom, e.g. from the puff adder (''Bitis arietans'') or brown recluse spider (''Loxosceles reclusa''). Cell physiology Treating cells ...

and regenerative cell

hyperplasia Hyperplasia (from ancient Greek ὑπέρ ''huper'' 'over' + πλάσις ''plasis'' 'formation'), or hypergenesis, is an enlargement of an organ or tissue caused by an increase in the amount of organic tissue that results from cell proliferati ...

. 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. A similar reclassification has been made for folpet, a structurally related fungicide, which shares a common mechanism of toxicity. A key finding for captan (and folpet) is these

s are not mutagenic in the animal ( in vivo).Gordon, E. B. 2010b. Captan and Folpet. In: R. Krieger, ed. Hayes Handbook of Pesticide Toxicology pp. 1915-1949. Elsevier, New York

Production

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

References

External links

Captan Technical Fact Sheet - National Pesticide Information CenterCaptan General Fact Sheet - National Pesticide Information Center
* ttps://web.archive.org/web/20061006123222/http://www.epa.gov/oppsrrd1/REDs/factsheets/0120fact.pdf EPA Captan Reregistration Eligibility Decision Factsbr>CDC - NIOSH Pocket Guide to Chemical Hazards - Captan
{{Authority control Fungicides Pesticides Sulfenamides Imides Trichloromethyl compounds