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PROTEACEAE(Protea family)
1050 species in 62 genera are found in tropical Asia, Malaysia, Australia, New Caledonia, New Zealand, tropical South America, Chile, on the mountains of tropical Africa and in southern Africa and Madagascar. Vases containing the flowers of the Australian shrub Lomatia silaifolia R.Br. (syns Embothrium silaifolium Sm., Tricondylus silaifolius Knight), which is commonly called crinkle bush, parsley fern, or wild parsley, are often surrounded by dead flies (Macpherson 1932). [Summary yet to be added] Cleland (1943) received several reports of dermatitis from contact with undried wood of this species. Only some of those exposed were affected. Webb (1948a) refers to the properties of the wood; sawyers and others handling the fresh timber may contract dermatitis (H.C. Whibley, Cairns, personal communication to Webb 1948a). The root of the plant yields lapachol (Thomson 1971), a sensitising agent of teak (Tectona grandis L.f., fam. Labiatae).
In the traditional medicine of the Mapuche Amerindians of Chile, an infusion of the leaves has been used to wash open wounds, and a poultice used to dress wounds (Houghton & Manby 1985). 190 species are found in eastern Malaysia, New Hebrides, New Caledonia and Australia. Some yield useful timber. Leichhardt (1847) cited by Hurst (1942) referred to the vesicating property of the glutinous secretion of the seed vessels of a drooping species of Grevillea. The skin turned black in colour as from the effects of silver nitrate and was raised in painful blisters. This property was discovered accidentally and was traced to Grevillea by means of experimental application of the capsules to the skin, when the same effect was produced. The passage, which preceded the introduction of the patch test to Dermatology by nearly half a century, is as follows: "John Murphy having no pockets in his trousers, put the seeds which he found during the stage into his bosom, close to the skin, where he had already deposited a great number of Sterculia, and was much inconvenienced by starry prickles which surround the seeds. Afterwards, finding the drooping Grevillea in fruit, he gathered some capsules and placed them as before stated. Upon arriving at the camp he felt great pain and, on examining the place, he saw, to his greatest horror, that the whole of the skin of the epigastric region was coloured black and raised into a great number of painful blisters. Upon his showing it to me, I thought that it was caused by the Sterculia prickles having irritated the skin and rendered it more sensitive to the sharp properties of the exudation of the seed vessels of Grevillea. Brown, however, merely touched the skin of his arm with the matter when blisters immediately rose, showing clearly its properties. The discoloration of the skin was like the effects of nitrate of silver." The natives of north-west Australia were observed to use the sap of two species of Grevillea to scarify their bodies and produce scars (Cleland 1925). In Hawai‘i, the flowers are a common source of dermatitis (Morton 1962a). A study was carried out by Arnold (1942). He found that women were more frequently affected than men. Dermatitis appeared two to three days after exposure and most often affected the dorsa of the hands, wrists, face and neck. Open patch tests with various parts of the plant produced marked reactions to the fresh flower and to ether extracts of the flower. Only a few slight reactions were obtained from closed patch tests with the leaf. The lesion detail of the dermatitis was typical of plant dermatitis viz. linear erythema and/or vesicles. The blossoms are made into bouquets and leis (neck garlands) which possibly accounts for the predominance in women (6/1). The calyx, anther and style of both the red and yellow varieties of blossom contained the allergenic principle. Cross-sensitivity to the blossom of Grevillea robusta did not appear to occur. He observed no case in which dermatitis appeared in less than 24 hours after exposure. Patch tests in control individuals were negative. Exacerbation of pre-existing dermatitis occurred in some cases following patch testing. Three of 26 patients showed some sensitivity to extracts of mango leaf (Mangifera, Anacardiaceae) probably by muitiple specific sensitivity rather than by cross-sensitivity. Kahili is also a colloquial name in Hawai‘i for Hedychium. The sticky secretion on the fruits of this tree in Queensland causes blistering of the skin as is well known by bushmen (Mair 1968a).
Aplin (1976) noted that two persons who walked through a patch of the shrub developed an intense rash.
Both the species and subspecies have a sticky secretion which can cause blistering on contact with the skin. Danger also exists from drops of the secretion when sitting under the tree (Francis & Southcott 1967, Cleland & Lee 1963). This species is now extensively employed as a shade and timber tree in Ceylon and elsewhere. The sap caused inflammation of the eyelids in a man who worked on the trees lopping or thinning out branches (Cleland 1925, Morton 1962a). The tree is used to line streets for shade purposes and in Los Angeles "Grevillea poisoning" is well known to telephone linemen and pruners (May 1960). Some of the laboratory staff most directly involved in handling and testing of specimens of this wood were affected with skin and eye irritation. Others as directly involved in this work were not affected. The irritation developed after handling green wood or following exposure to sawdust or exuded sap. It was not observed as a result of handling the dry prepared specimens (U.S. Forest Service Research Note 1964). A male, developed vesicobullous dermatitis of the skin of the neck, arms, trunk and genital area, two days after he sawed a limb off a specimen of this tree. Sawdust fell on his face, neck and down into his clothing. A patch test to the sawdust produced a. bullous response at 36 hours; tests in controls were not recorded (May 1960). The major phenolic constituent of the wood is grevillol (5-n-tridecylresorcinol) (Cannon et al. 1970). Grevillea robusta, Grevillea pyramidalis and Persoonia elliptica have been found to yield 5-n-alkyl and 5-n-alkenylresorcinols. The major constituent of the vesicant exudate on the seed pods of Grevillea pyramidalis has been identified as 5-pentadec-10-enylresorcinol and traces of the same substance have been shown to be present in the wood of Grevillea robusta (Ritchie et al. 1965, Occolowitz & Wright 1962, Ridley et al. 1968). These compounds are chemically related to the sensitising compounds of Toxicodendron. An ether extract of this wood was found to be vesicant to human skin: the volatile portion of the extract was responsible and blisters appeared within 10 hours of application to the skin of the forearm. 5-n-Undecylresorcinol and (Z)-5-undec-3-enylresorcinol (persoonol) were isolated from the extract (Cannon & Metcalf 1971). References
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