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MORACEAE(Mulberry family)
This family includes about 1400 species in 53 genera. Most are trees or shrubs of the tropics or subtropics, but a few species are indigenous to temperate regions. Lac (shellac) is produced on several species by the punctures of an insect. Shellac is lac melted and run into thin plates (Oxford English Dictionary). Shellac is a resinous excretion of the insect Laccifer (Tachardia) lacca produced on certain trees (Estrin 1973). Shellac can produce allergic contact dermatitis (Fisher 1973). [Summary yet to be added] This tree yields a useful timber (known as antiaria) for general constructional purposes, and is exported to Europe in small quantities (Hausen 1973). Whilst it shares to some extent the toxic properties of Antiaris toxicaria, it is by no means so aggressively irritant. This tree of legendary ill-repute was believed to kill all who came near it (White 1887, Menninger 1967). It contains cardioactive glucosides (Hausen 1973, Wehrli et al. 1962) which have been used as arrow poisons. The use of the timber is limited by its toxicity. The bark is made into a fabric which may irritate the skin, unless the bark fibre is thoroughly cleaned of all traces of latex (Burkill 1935, Osol and Farrer 1955). Dermatitis resembling that caused by poison ivy / oak (Toxicodendron Mill. spp., fam. Anacardiaceae), accompanied by an erysipelatous swelling of the body, dizziness and nausea may occur in those climbing the tree. The sap is also regarded as dangerous to the eyes and to have caused blindness (Van Hasselt & Henkel 1882, Großmann 1920). The sap is said to be harmless on unbroken skin (Gimlette 1929) but may irritate scratches (Irvine 1961). Forty-seven species are found in south-eastern Asia and Indo Malaysia. Several species are cultivated all over the tropics including Artocarpus altilis Fosberg (bread-fruit) and Artocarpus heterophyllus Lam. (jak). The fruits of some species weigh as much as 10 kg. Such species are not recommended for planting at roadsides or in gardens. The timber is useful and that of Artocarpus integrifolia L.f. has been called Ceylon mahogany (see Pterocarpus santalinus L.f., fam. Leguminosae).
The root yields bergapten, psoralen and other coumarins, the photosensitising capacity of which has been investigated (Martins et al. 1974).
The wood is so extremely hard that it will not accept nails, but it has some uses and is imported to Europe in limited quantities (Hausen 1970). Workers with the wood of this species developed headache, irritation of the nose and throat, nausea and skin inflammation (Großmann 1920). The sawdust produced salivation and severe thirst and all parts of the tree were very irritating to the skin where it was thin (Freise 1932). This author rubbed a powder of the bark into his own forearm; a burning inflammation developed and left a stain which persisted for some weeks. Hausen (1970) found evidence of quinones in the wood, chemically related to those of Brosimum paraense. Two coumarins have been isolated from the wood, but phototoxic effects have not been reported as such (Hausen 1970). Alcohol/chloroform extracts of the wood produced sensitisation in guinea pigs (Hausen 1974).
The wood contains quinones chemically related to those found in Piratinera guianensis Aubl. (Hausen 1970). Guinea pigs could be sensitised to an ethanol/chloroform extract of the wood (Hausen 1974). A report of toxicity from the wood of bois de feroles (Czimatis and Hagemann 1910) seems to refer to Brosimum paraense and not to Ferolia spp. (Woods and Calnan 1976 citing Record & Hess 1943). Seven or eight species are native to eastern Asia. The bark of Broussonetia papyrifera (L.) L'Hér. ex Vent., the paper mulberry, provides a fibre used for paper and cloth. The pollen of some species can cause hayfever (Wodehouse 1971). The plant causes itching of mild degree (von Reis Altschul 1973). Some 800 species are widely distributed throughout the warmer regions of the world. When the word fig is used without qualification it refers to Ficus carica, which has been cultivated for millenia and has been very widely dispersed from its point of origin which was probably in the area of which Syria is the centre (De Candolle 1886),in which the fig grows wild. The fig is cultivated wherever the climate is suitable, and survives, although it does not prosper, even in Northern Europe. Some other species of Ficus L. yield edible figs. Others are cultivated as ornamental plants. The rough leaves are used as an abrasive by carpenters in Africa, and the sap is used as a gloss for blackening boots and shoes (Irvine 1961). It is not reported whether it shows the irritant or photosensitising properties of some other species. This plant is reported as irritant (Burkill 1935). The rough leaves are used as an abrasive (Williamson 1955). The fig and the tree which bears it have for so long formed such an important component of man's environment in the Mediterranean region, the Near and Middle East and parts of India, that its products have come to occupy a place in ancient and in modern indigenous medicine. Man comes into intimate contact with the fruit as cultivator, gatherer, packer or consumer, or even as a carpenter, although the timber is of limited value and is mainly used locally for boxes and other small articles (Hausen 1970). In NW Moroccan traditional medicine, the latex from the leaf is applied to insect stings and to cutaneous ulcers (Merzouki et al. 2000). The latex contains a proteolytic enzyme, ficin (Budavari 1996) which is irritant to inflamed skin and to the conjunctiva (Watt & Breyer-Brandwijk 1962). It has pruritogenic properties similar to those of mucunain (Arthur and Shelley 1955) and is irritating to skin and eye (Grant 1962). The latex yields also ficusin, a psoralen, and 8-methoxypsoralen (Pathak et al. 1962). The sap of peel, fruit and leaves was a photosensitiser in all test subjects (Kitchevatz 1934, 1936). "But ye vitiligines albae are cataplasmed with ye leaues or ye boughes of ye Black Figge" (Dioscorides c. 50 A.D.). It appears therefore that the capacity of the sap of the fig to induce pigmentation was known almost 2000 years ago. The sap was used as a counter-irritant in Southern Europe by the 13th Century (Straton 1912) and probably earlier. It is used in India in the treatment of eczema and psoriasis (Behl et al. 1966). The precise causes of the various clinical syndromes are debatable. Conflicting statements concern in particular the direct irritancy of the sap. In such a widely established species with numerous named cultivars and spontaneously developed varieties, it could be predicted that such properties as the irritancy of the sap would be very variable. In many reports of patch tests the possibility that an irritant reaction might occur has been ignored. On the present evidence it is fair to say that figs cause irritant dermatitis, but vary in their capacity to do so. Whether figs can also cause an allergic contact dermatitis is uncertain. Figs can also cause a photodermatitis, but by what mechanism is not known - a possible role of psoralens is not clearly defined; there is no convincing evidence that an immunological process is concerned. In the act of picking the fruit, the brittle hairs that cover the leaf readily penetrate the flexor surfaces of the fingers and wrists, and in individuals with irritable skins a dermatitis follows in twenty-four hours, each hair having produced a minute papule with a small inflammatory area surrounding it. Children, with their more delicate and irritable skins, most usually suffer from this kind of dermatitis (Davidson 1899); as this author points out the fig leaf seems to be a most unsuitable choice for an article of clothing. Whilst some authors find the fig itself non-irritant (Davidson 1899) others, for example Maiden (1909b) say that the peel irritates the mouth and that some individuals develop dermatitis from gathering green figs. However contact with the latex could presumably not be completely excluded in this case, and this is certainly the principal cause of dermatitis in fig gatherers. It has been reported from Turkey (Behcet et al. 1938) and from California (Legge 1921): some immediate discomfort is experienced and vesicles develop after 3 or 4 hours. Therapeutic applications of the sap have been followed by ulceration (Straton 1912) and, in India, by bullous dermatitis, ulceration, hyperpigmentation, depigmentation and even keloidal scars (Behl et al. 1966). Straton (1912) noted that contact with fig sap could result in pigmentation lasting as long as 30 years; the pigmentation could be prevented by washing the hands soon after contact. The role of sunlight in provoking the reactions to fig sap was noted by Vigne and Ponttlieu (1936) and was investigated by Behcet et al. (1938, 1939) in Turkey. Behcet had earlier (1933) reported that dermatitis could be induced with either the sap or a decoction of the leaves. The methods of investigators then available were limited but it could be shown that whilst some patients had a true photodermatitis, provoked by sunlight, others developed a bullous reaction to an alcoholic extract of fig even if protected from light. Berlin (1930) reported that fig dermatitis was common in Palestine during the summer months, and affected mainly boys aged 6 to 12. A bullous eruption developed on exposed skin, mainly on the limbs and around the mouth, and was followed by pigmentation. Fig sap has produced a bullous reaction on the author's arm (JCM) after 48 hours. Photodermatitis from contact with the fresh figs or foliage was reported by Kuske (1938, 1940) and Rossetti (1947). The cases of bullous dermatitis reported by Paionne (1938) were probably light-induced. On the other hand Furtado (1951) observed photodermatitis of the hands and arms, followed by streaky hyperpigmentation, after the use of an extract of fig leaves as a shampoo; a patch test was negative. Five other patients with a similar reaction had earlier been reported (Aleixo 1935) but were not patch tested. An infusion of fig leaves reputed to remove stains caused dermatitis in two patients who used it to wash clothes (Pershangov 1965). Those engaged in drying, packing or cooking figs sometimes develop a chronic eczema of the fingers and hands, which may be associated with paronychia (Behl et al. 1966), but even in these occupations the clinical picture is variable. Six candy-makers, and a housewife who cooked figs, all developed a bullous photodermatitis with pigmentation (Popoff and Zaharieff 1935). An elderly tabourer who was employed in drying figs developed after 24 hours an irritable eruption of face and neck and axillae, of uncertain causation (Emido 1940). The diagnosis of fig dermatitis is further complicated by the fact that dried figs, like other stored foods, may harbour a mite, Carpoglyphus, which may give rise to an extensive papular eruption (O'Donovan 1920, Belisario 1948, Pirila 1951, Rokstad 1943). This plant is reported as irritant (Burkill 1935). This species is popular as a house plant and is much favoured for the decoration of waiting rooms and offices. It is a possible cause of allergic dermatitis; a patch test to a leaf was positive in one patient (Agrup 1969). The twigs, leaves and figs are set with short stinging bristles (Corner 1952). The nature of the stinging effect is unknown.
Ingestion of the dried unripe fruit and application of powder to the skin produced a lowered minimal erythema dose by irradiation with an ultraviolet lamp (Ansari et al. 1975). [Information available but not yet included in database]
This plant is irritant; a patch test was positive in 8 of 38 persons (Fregert and Hjorth 1969).
According to Maiden (1920), a gardener who rubbed his eyes after working with Ficus stipulata experienced intense irritation of the eye. Soldiers engaged in clearing an area in which wild fig trees (Ficus tumila [sic]) were growing suffered from blistering of the skin on the face and arms, intense conjunctivitis, and severe catarrhal irritation of the naso-pharynx. Transfer to the genitals also occurred. Experimental application of the sap to the forearms produced erythema and vesiculation after 12 hours, despite the subject having had a swim in the ocean one hour after the sap had been applied (English & Grey 1943). The leaves are irritant to workers who chop them up and mix them with opium (Burkill 1935).
The leaves of Ficus mallotocarpa are abrasive (Williamson 1955). The leaves of Ficus exasperata are used as an abrasive (Irvine 1961). The sap is strongly irritant (Burkill 1935).
[Information available but not yet included in database]
This species bears spines capable of inflicting mechanical injury. Accordingly, it can be planted to make an impenetrable hedge (Hunt 1968/70). The native Americans made bows from the branches. The trunk provides a heavy and durable yellow timber used by turners and cabinet makers (Alden 1995). The bark yields a yellow dye which has been used as a substitute for fustic from Maclura tinctoria D.Don ex Steud. [see below]. The fruit is inedible. Contact with the sap from this tree can cause dermatitis (Schur 1932). Subsequent reports (Muenscher 1951, Gardner & Bennetts 1956, Schwartz et al. 1957) are brief and may all derive from Hurst (1942) and/or Schur (1932). It is by no means clear whether the sap is irritant or sensitising or both.
This tree is the source of the yellow dye "old fustic" (Remington et al. 1918), one of the dyes used to produce khaki uniforms for the military during World War I (Purseglove 1974) — see also Acacia catechu Willd., fam. Leguminosae. The timber from this tree is said to have irritant and sensitising properties (Guns 1932, Pêche 1947, Hausen 1981a) similar to those of Chlorophora excelsa Benth. & Hook.f. Until recently, the two tree species in this genus found in tropical Africa were classified in the genus Chlorophora Gaudich. Both yield a valuable timber, which bears a superficial resemblance to oak (Quercus robur L., fam. Fagaceae) or to teak (Tectona grandis L.f., fam. Labiatae), and which has been sold under a confusing multiplicity of trade names. The most important species is Milicia excelsa C.C.Berg, which is most commonly named Chlorophora excelsa or simply Chlorophora in the literature. However, it is important to point out that the timbers from both this species and from Milicia regia C.C.Berg (syn. Chlorophora regia A.Chev.) are known as iroko or kambala, and that dermatologic studies have hitherto almost never been carried out on botanically authenticated wood samples.
The timber is strong, durable and weather resistant and is much used for outdoor and indoor constructional work, including boat building. The alkaloid chlorophorin is an allergic sensitiser (Schulz 1957, 1960, 1962, 1967). The molecule is composed of a four-fold oxidized stilbene nucleus and an aliphatic side chain, and is chemically related to the allergenic compounds of Toxicodendron (King and Grundon 1949, 1950). Dermatitis affects carpenters, joiners and other wood workers, rather than those felling the trees. The sawdust was recognised as causing dermatitis of eyelids and genitalia, in Breslau over 60 years ago (Czimatis and Hagemann 1910). Iroko is amongst the six commonest causes of dermatitis from woods in France (Zafiropoulo et al. 1968). However the latex oozing from the freshly felled timber appears to be irritant and has caused acute, followed by chronic, dermatitis in East African workers (Piorkowski 1944). There are numerous reports of dermatitis in wood workers; taken together the reports provide a graphic picture of a severe dermatitis, sometimes associated with ocular and respiratory symptoms, and assuming almost epidemic proportions particularly where high temperature and humidity favour eccrine sweating. The earliest clinical and chemical studies were made in Germany and France (Hubinot 1928, Frei 1931, 1932, Loro 1923). In an outbreak of dermatitis in a joiners' workshop Jung (1967) noted positive patch test reactions to the sawdust. Goessens (1936) reported a case of generalized dermatitis caused by the sawdust. Frei (1932) obtained positive patch test reactions with sawdust and Ragot and Brun (1948) with an aqueous extract. Thienemann (1941) noted the development of dermatitis in a proportion of workers approximately ten weeks after this wood was first introduced. He gave a good description of the distribution of the dermatitis, which involved the arms, the face and chest and the scrotum. The incidence of dermatitis in some workshops has been very high: in one machine shop all of the more than 50 workers were affected in some degree, though only 9 had severe dermatitis, sometimes accompanied by upper and lower respiratory tract symptoms (Davidson 1941). This variation in the clinical picture was noted also by Langelez (1950); some workers developed only a mild papular prurigo of exposed or covered skin, a few developed dermatitis particularly of the neck and ears, and some in each group had conjunctivitis and asthma. This variation suggests that the sawdust both irritates and sensitises, and the investigation of a case of dermatitis in a machinist supported this assumption. Patch tests with the dry dust were positive in the patient and in 4 of 5 control subjects, but tests with 0.1% chlorophorin in soft paraffin were positive only in this patient (Beer 1970). Respiratory symptoms may be severe. Obstructive rhinitis without asthma occurred in men handling iroko and bé té and both rhinitis and asthma in another who worked with iroko, obèche, Triplochiton and framiré (Zafiropoulo et al. 1968). In reporting 11 cases of asthma in men exposed to the dust of iroko and teak (Tectona grandis L.f., fam. Labiatae), Van Ganse (1968) noted that only a proportion of these patients gave positive scratch test reactions and that inhalation tests were sometimes positive when these were negative. It is not established whether the respiratory symptoms are purely irritant in origin or whether a reaginic antibody is implicated. For patch testing, 1% chlorophorin in soft paraffin is probably suitable, unless this concentration is proved to sensitise some subjects (Maibach 1970). In one patient patch tests with 0.1% chlorophorin were negative, whilst tests to 0.5% and 1.0% were positive (Wilkinson 1969). Referring to "Iroko (chlorophra excelsa)", Raymond (1959) noted that the timber can produce dermatitis in construction workers. Thiel (1960) reported contact sensitivity to the wood. Kambala was listed by Hublet et al. (1972) and by Oleffe et al. (1975a) as a cause of dermatitis in the Belgian timber industry. There are about 10 species widely distributed in North and South America, tropical Africa and southwest Asia. Several species are cultivated for their edible fruit, the mulberry, or for their leaves, which are fed to silkworms.
These three species are used to feed silkworms (as are various other trees). The leaves of M. rubra are said to cause dermatitis (Hardin & Arena 1974), but no documented reports of dermatitis from any part of the tree have been discovered. Disorders of eyes, skin or respiratory tract, which affected one half of the workers on a silkworm farm, were attributable to the hairs and scales of the moths, Bombyx mori (Marconi et al. 1951, Paun et al. 1964) and to a toxic substance from the cocoons (Kochergin 1957). Cresol was incriminated by Goodman in 1933. Potton (1851-1852), cited by White (1887), referring to "mal de vers [or] mal de bassine" [= silk winders' dermatosis], described an inflammatory affection of the hands among silk weavers who unwind the silk from the cocoons. He (Potton) attributed the disease to the presence of the worm [= caterpillar] in its cocoon, to its decomposition and to changes which gradually take place in its interior. The pollen of some species can cause hayfever (Wodehouse 1971). [Information available but not yet included in database]
Maiden (1920) reported the statement of a correspondent that the sap of Pseudomorus brunoniana was severly irritant to the eyes. Subsequent authors have cited this apparently isolated report (e.g. Hurst 1942). References
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