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EBENACEAE
This family of 500 species of trees and shrubs in 3 genera (Euclea L., Diospyros L., and Lissocarpa Benth.) occurs in tropical regions especially in Indonesia. The fruits of some species are edible and may be found as articles of commerce. Diospyros virginiana L. provides the persimmon; D. kaki Thunb. provides the kakee or Chinese persimmon; the fruit of D. lotus L. is known as the date plum. Diospyros ebenum J. König is the best source of ebony, a very heavy and strong timber. It is characteristically jet black but sometimes streaked with yellow or brown. Euclea pseudebenus E.Mey. and other species of Diospyros also provide valuable ebony-like timber. Contact with leaves, bark, fruit, root, or the wood dust of members of this family has caused dermatitis and vesication. Irritation of the respiratory tract may also occur in woodworkers. A number of species are known to contain naphthoquinones including the irritant compound plumbagin (see also Plumbaginaceae). Some 500 species are found in warm regions. The sapwood is white and soft, the heartwood hard and black. Ebony refers to the heartwood of various species. An ebony bracelet produced dermatitis of the wrist (Nicolas & Pétouraud 1935). The wood dust of some species is irritant to the respiratory tract (Orsler 1973). Ebony sawdust added to snuff as a practical joke caused violent persistent irritation (Großmann 1920). Hausen (1981) believes that the naphthoquinones that occur in Diospyros species are responsible for the allergic contact dermatitis caused by the timbers. Presumably referring to this species, Prosser White (1934) notes that "Diosperus acris makes blisters". This tree has downy shoots sometimes ending in a thorn (Chittenden 1969).
Oliver (1959), referring to D. xanthochlamys, and Irvine (1961), referring to D. canaliculata, note that a bark extract blisters the skin. The bark and leaves of D. xanthochlamys have been reported to contain plumbagin (Paris & Moyce-Mignon 1949). See also Plumbaginaceae. Dermatitis of the face hands and forearms of a 70 year old cabinet maker and in other workers at the same place was ascribed to the wood of this species by Buschke & Joseph (1927, cited by Hausen 1981a). Patch tests to the sawdust and an alcoholic extract produced negative results but an intradermal test, which was negative in controls, provoked a positive response. An ebony splinter wound was followed by eczema after contact with macassar ebony sawdust; no patch tests were recorded (Vonkennel 1929a, Vonkennel 1929b). Schürkämpfer (1972) observed one positive patch test reaction to macassar ebony in 173 persons working in a veneer factory. Bleumink & Nater (1974) observed four positive patch test reactions to coromandel. Contact dermatitis and respiratory disorders from the wood dust have been reported from Switzerland (Hartmann & Schlegel 1980). Hausen (1981a) suggests that macassar II, a β-naphthol derivative found in the timber of this species, may become oxidised in vivo to macassar quinone. This compound has been shown to have sensitising properties in guinea pigs. Cross-sensitivity to other naphthoquinones has also been demonstrated in guinea pigs thus sensitised (Hausen 1981a). Rackett & Zug (1997) described a case of a domestic woodworker who had worked with several exotic woods and developed allergic sensitivity to macassar ebony and as well as to zericote, pao ferro, cocobolo, becote, and padauk. Later testing confirmed sensitivity to R-3,4-dimethoxydalbergione (found in pao ferro), obtusaquinone (found in cocobolo), and macassar quinone (found in macassar ebony). The timber has been suspected of causing contact dermatitis (Hausen 1981). The timber of this species has been reported to cause dermatitis (Legge 1907, Herxheimer 1912, Lewin 1928, Nicolas & Pétouraud 1935, Hausen 1981). The edible fruit has a dense covering of irritating silky hairs (Corner 1952). The bark and leaves are employed as a blistering plaster (Quisumbing 1951). The sawdust of this species has been reported to cause dermatitis (Herxheimer 1912, Rasch 1925, Reinl 1965, Hausen 1981). Cooke et al. (1952) referring to D. hebecarpa, reported that the bark and leaves contain plumbagin. See also Plumbaginaceae. Ulcerative stomatitis can result from using this plant to clean the teeth (Verdcourt & Trump 1969). The roots of this species contain plumbagin (Tezuka et al. 1972, 1973). See also Plumbaginaceae. This species is used in southern Africa to dye the teeth red (Watt & Breyer-Brandwijk 1962). The bark and roots of this species have been reported to contain plumbagin and other monomeric and dimeric naphthoquinones (Meijer 1947, Tezuka et al. 1973). See also Plumbaginaceae. The timber has been suspected of causing dermatitis (Hausen 1981). Plumbagin has been reported to occur in the bark of this species; only traces were found in the leaves (Paris & Moyce-Mignon 1949). See also Plumbaginaceae. The juice of the fruit is irritating to the skin; the bark and leaves are caustic (Quisumbing 1951, Perry & Metzger 1980). The plant can cause dermatitis and the fruit juice can blister the skin (Uhe 1974). Fallas & Thomson (1968), referring to D. elliptifolia, reported that the bark contains plumbagin and other naphthoquinones. See also Plumbaginaceae. The specific epithet of the synonym suggests that the plant may cause itching of the skin. The plant is vesicant to the skin and has been used in southern Africa as a counter-irritant (Watt & Breyer-Brandwijk 1962). The timber has been suspected of causing contact dermatitis (Hausen 1981). Some 20 species are found in Africa, the Comoro Islands, and Arabia. The wood of this tree is never used as firewood by Zulus because this leads to quarrels and domestic unhappiness (Watt & Breyer-Brandwijk 1962). This plant, when placed for medicinal purposes on cuts in the skin, is said to produce poisonous effects (Verdcourt & Trump 1969). References
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