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(Soapberry family)

2000 species in 150 genera are found in tropical and subtropical regions. Litchi chinensis furnishes edible fruit (litchi).

Acer palmatum Thunb. and other species are often planted as ornamental trees and shrubs. They are also popular as subjects for bonsai, a natural art form produced by artificially stunting the growth of the specimen.

Many species of Acer yield good timber. Acer saccharum Marshall and other species in eastern North America yield maple syrup.

The pollens of the anemophilous species, less commonly the amphiphilous and entomophilous species, are minor causes of pollinosis (Wodehouse 1971). Inhalation of fungal particles from maple bark (Acer L. spp.) can cause maple bark disease, a form of allergic alveolitis (Seaton & Morgan 1984).

[Summary yet to be added]

Aesculus hippocastanum L.
[syn. Hippocastanum vulgare Gaertn.]
Horse Chestnut, Oblionker Tree

A particle of the shell of the horse chestnut became embedded in the conjunctiva and caused necrosis and ulceration by a local toxic effect (Grant 1974).

Aesculus octandra Marshall
Yellow Buckeye

The flowers and young shoots of some species, especially Aesculus octandra, are said to be capable of causing contact dermatitis (Massey 1941).

Acer L.

Species of Acer L., Tilia L. (fam. Tiliaceae), and certain other deciduous trees may become heavily infested with aphids living on the undersides of the leaves. Whilst feeding, these insects excrete a sugary liquid known as honeydew which falls from the trees as a fine rain. Large numbers of aphids may also fall from the trees. A case has been described where an elderly woman with suspected delusions of parasitosis (Ekbom's syndrome) who, after unknowingly sitting under a species of Acer during the summer months, complained of a sticky feeling and a crawling sensation caused by green insects on her skin (Mitchell 1975).

Maple is said to be a sensitising wood by Weber (1953), repeated by McCord (1958).

Acer macrophyllum Pursh
Big-Leaf Maple, Oregon Maple

The fruits (maple keys) are covered with spiny hairs that can penetrate and irritate the skin (Hebda 2003).

Acer negundo L.
[syn. Negundo aceroides Moench]
Box Elder Maple

The pollen of this and another species of maple has been implicated as a cause of airborne contact dermatitis by Lovell et al. (1955) who observed positive patch test reactions to "box elder pollen oil" and to "maple pollen oil" in two patients.

Acer nikoense Maxim.
[syns Acer maximowiczianum Miq., Crula nikoense Nieuwl., Negundo nikoense Miq.]
Nikko Maple

4-(4-Hydroxyphenyl)-2-butanol, an arylbutanoid known as 4HPB, rhododenol, or more correctly, rhododendrol, is found naturally in this species (Das et al. 1993). This substance inhibits tyrosinase in the skin and therefore can cause leukoderma and vitiligo-like symptoms (Kasamatsu et al. 2014, Sasaki et al. 2014, Nishigori et al. 2015). Both R-(–) and S-(+) enantiomers of rhododendrol exhibit this activity (Ito et al. 2014). Rhododendrol [CAS RN 69617-84-1]a has been included in proprietary skin-lightening products, but these have been withdrawn from the market, and users advised against their use following reports of the appearance of white blotches on the skin of users.

Rhododendrol is also found in certain species of Rhododendron L., fam. Ericaceae (Archangelsky 1901, Das et al. 1993) and Betula L., fam. Betulaceae (Santamour & Vettel 1978, Santamour & Lundgren 1997).

Acer pictum Thunb.

Nadkarni (1976) states that the leaves of this species are irritant.

Acer platanoides L.
Norway Maple

The wood was listed as irritant by Hanslian & Kadlec (1966), probably from Weber (1953).

Acer rubrum L.
Red Maple, Swamp Maple

An extract of the bark has been used for its astringent effect in the treatment of sore eyes by North American Indians (Wren 1975).

Acer saccharum Marshall
Sugar Maple

This species has been found to contain 2,6-dimethoxy-1,4-benzoquinone, a known contact allergen (Hausen 1978a).


Cardiospermum halicacabum L.
[syns Cardiospermum corindum L., Cardiospermum luridum Blume, Cardiospermum microcarpum Kunth, Cardiospermum molle Kunth, etc.]
Blister Creeper, Balloon Vine

The leaves is irritant and are used for rubefacient purposes (Quisumbing 1951, Gardner & Bennetts 1956, Watt & Breyer-Brandwijk 1962, Behl et al. 1966). Gardner & Bennetts (1956) also note that the root has been used in the treatment of haemorrhoids, probably from Webb (1948a).

Deinbollia oblongifolia Radlk.
[syns Sapindus oblongifolius Sond., Rhus oblongifolia E.Mey. ex Arn.]
Dune Soapberry

A foam is produced by shaking the berries from Sapindus oblongifolius with water (Watt & Breyer-Brandwijk 1962).

Hippobromus pauciflorus Radlk.
[syns Hippobromus alata Eckl. & Zeyh., Rhus alatum Thunb.]

A decoction of the plant is used in southern Africa as a sternutatory. Frothing of the roots, when mixed with water, may indicate the presence of saponins (Watt & Breyer-Brandwijk 1962).

The genus is monotypic.

Melicoccus bijugatus Jacq.
[syns Melicoccus bijuga L., Melicoccus carpopodea Juss., Paullinia sphaerocarpa Rich. ex Juss.]
Genipe, Honey-Berry, Mamoncillo, Spanish Lime

This species which provides timber and edible fruit was reported to cause contact dermatitis by Pardo Costello & Reaud (1941).

Paullinia cupana Kunth
[syn. Paullinia sorbilis Mart.]

The fruit of this climbing shrub provides an edible seed rich in caffeine. It was formerly officinal (Remington et al. 1918, Todd 1967).

Piffard (1881), citing an earlier report by Montegazza, noted that ingestion of guarana [seed ?] has been reported to cause urticaria and pruritus.

Paullinia Cupana Fruit Extract / Fruit Powder / Seed Extract / Seed Powder / & Seed Water [INCI; CAS RN 84929-28-2]a, are recognised cosmetic product ingredients variously purported to have skin conditioning, astringent, tonic, and/or emollient properties, as is also Caffeine [INCI; CAS RN 58-08-2; masking & skin conditioning] (Standing Committee on Cosmetic Products 2019, CosIng 2021). According to Baumann (2007), caffeine is well known to cause dehydration of fat cells, temporarily improving the appearance of cellulite and is a common additive to cellulite treatment products.

Koo et al. (2007) reported that topical application of caffeine after UV exposure decreases UV-induced skin roughness and transverse rhytids in SKH-1 hairless mice.

Paullinia pinnata L.
[syns Paullinia angusta N.E.Br., Paullinia hostmannii Steud., Paullinia pendulifolia Rusby]
Bejuco de Costillo, Sweet Gum, Paullinie

The root and root bark are applied for rubefacient purposes (Watt & Breyer-Brandwijk 1962).

Sapindus saponaria var. drummondii L.D.Benson
[syn. Sapindus drummondii Hook. & Arn.]
Jaboncillo, Western Soapberry

Dermatitis can result from handling of the fruits (Schwartz et al. 1957).

Sapindus saponaria L. var. saponaria
[syns Sapindus divaricatus Cambess., Sapindus inaequalis DC., Sapindus mukorossi Gaertn., Sapindus peruvianus Walp., etc.]
False Dogwood, Jaboncillo, Soap-Nut Tree, Southern Soapberry, Wingleaf Soap Berry

The berries form a lather with water and may be used as soap. They contain saponins that may cause a severe skin rash in sensitive individuals (Allen 1943, Blohm 1962, Morton 1962a). Behl et al. (1966) similarly noted that the pulp of the fruit of Sapindus mukorossi forms a lather with water and may be used as a shampoo.

The juice of the fruits of Sapindus mukorossi is used for removing freckles (Smith 1969).

Schleichera oleosa Oken
[syns Pistacia oleosa Lour., Schleichera trijuga Willd.]
Kussum, Paka, Ceylon Oak, Zeepboom

Shellac is a resinous excretion of an insect which sucks the juices of this and other trees (Hicks 1961). This tree yields Mirzapore lac and also, useful timber, edible seed and seed oil. Macassar oil (kusum oil) is derived from the seed kernels (Budavari 1996). Macassar oil is also a name for ylang-ylang oil from Cananga. Macassar oil may contain additives such as safflower oil from Carthamus tinctorius L., (fam. Compositae). Harry (1948) referred to two papers concerning dermatitis or allergy from the oil but considered it innocuous. Shellac is said to have irritant or sensitising properties (Greenberg and Lester 1954) and has been removed from certain brand-name cosmetics (Anon 1973). Hausen (1970) refers to Wehmer (1929) and Anon (1940) for injurious effects of the plant products. The oil of macassar wood, possibly of this species, caused dermatitis in a planer (Buschke and Joseph 1927). Shellac is noted under Acer.

The genus is monotypic.


  • Allen PH (1943) Poisonous and injurious plants of Panama. American Journal of Tropical Medicine 23(Suppl): 3-76 [doi] [url]
  • Anon (1940) Giftige en voor de gezondheid nadeelige houtsoorten. Hout 20: 184.
  • Anon (1973) Almay Hypo-Allergenic Cosmetics Product Formulary, 8th edn: Schieffelin and Co., Pharmaceutical Laboratories Division, 562-5th Ave., New York, N.Y. 10036
  • Archangelsky K (1901) Ueber Rhododendrol, Rhododendrin und Andromedotoxin. [On rhododendrol, rhododendrin und andromedotoxin]. Archiv für Experimentelle Pathologie und Pharmakologie 46(3-4): 313-320 [doi] [url]
  • Baumann LS (2007) Less-known botanical cosmeceuticals. Dermatologic Therapy 20(5): 330-342 [doi] [url] [url-2] [pmid]
  • Behl PN, Captain RM, Bedi BMS, Gupta S (1966) Skin-Irritant and Sensitizing Plants Found in India. New Delhi: PN Behl [WorldCat]
  • Blohm H (1962) Poisonous Plants of Venezuela. Cambridge, MA: Harvard University Press
  • Budavari S (Ed.) (1996) The Merck Index. An Encyclopedia of Chemicals, Drugs, and Biologicals. 12th edn. Whitehouse Station, N.J.: Merck & Co., Inc.
  • Buschke, A. and Joseph, A. (1927) Uber Hautentzundung, Hervorgerufen durch Makassarholz mit Berucksichtigung gewerbehygienischer Fragen. Deutsch. Med. Wchnschr. 53: 1641.
  • CosIng (2021) COSING Ingredients-Fragrance Inventory v2 13/12/2021. [online article]: https://ec.europa.eu/growth/tools-databases/cosing/pdf/COSING_Ingredients-Fragrance%20Inventory_v2.pdf ; accessed December 2021 [url] [url-2]
  • Das B, Padma Rao S, Srinivas KVNS, Yadav JS (1993) Stereospecific synthesis and absolute configuration of (+)-rhododendrol. Phytochemistry 33(6): 1529-1530 [doi] [url]
  • Gardner CA, Bennetts HW (1956) The Toxic Plants of Western Australia. Perth: West Australian Newspapers [WorldCat]
  • Grant WM (1974) Toxicology of the Eye, 2nd edn. Springfield, Ill.: Charles C Thomas
  • Greenberg, L.A. and Lester, D. (1954) Handbook of Cosmetic Materials. New York. Interscience.
  • Hanslian L, Kadlec K (1966) Dřevo z hlediska hygienického (VIII). Biologicky účinné a málo účinné dřeviny. [Wood from a health perspective (VII). Trees with some or little biological activity]. Drevo 21: 229-232
  • Harry, R.G. (1948) Cosmetic Materials. Vol. 2. London. Leonard Hill.
  • Hausen, B.M. (1970) Untersuchungen uber Gesundheitsschadigende Holzer. Thesis, Hamburg.
  • Hausen BM (1978a) Sensitizing capacity of naturally occurring quinones. V. 2.6-Dimethoxy-p-benzoquinone: occurrence and significance as a contact allergen. Contact Dermatitis 4(4): 204-213 [doi] [url] [url-2] [pmid]
  • Hebda R (2003) Plant profile: Acer macrophyllum. Menziesia 8(3): 14-15 [url]
  • Hicks, E. (1961) Shellac, its Origin and Applications. Chemical Publ. Co., New York.
  • Ito S, Gerwat W, Kolbe L, Yamashita T, Ojika M, Wakamatsu K (2014) Human tyrosinase is able to oxidize both enantiomers of rhododendrol. Pigment Cell & Melanoma Research 27(6): 1149-1153 [doi] [url] [url-2] [pmid]
  • Kasamatsu S, Hachiya A, Nakamura S, Yasuda Y, Fujimori T, Takano K, Moriwaki S, Hase T, Suzuki T, Matsunaga K (2014) Depigmentation caused by application of the active brightening material, rhododendrol, is related to tyrosinase activity at a certain threshold. Journal of Dermatological Science 76(1): 16-24 [doi] [url]
  • Koo S-W, Hirakawa S, Fujii S, Kawasumi M, Nghiem P (2007) Protection from photodamage by topical application of caffeine after ultraviolet irradiation. British Journal of Dermatology 156(5): 957-964 [doi] [url] [url-2] [pmid]
  • Lovell RG, Mathews KP, Sheldon JM (1955) Dermatitis venenata from tree pollen oils. A clinical report. Journal of Allergy 26(5): 408-414 [doi] [url] [pmid]
  • Mabberley DJ (2008) Mabberley's Plant-Book. A portable dictionary of plants, their classification and uses, 3rd edn. Cambridge: Cambridge University Press [WorldCat]
  • Massey AB (1941) Plant poisoning. Merck's Report 50: 24
  • McCord CP (1958) The toxic properties of some timber woods. Industrial Medicine and Surgery 27(4): 202-204 [pmid]
  • Mitchell JC (1975) Cutaneous effects from rain-tree honeydew and aphis insects. International Journal of Dermatology 14(10): 761-762 [doi] [url] [url-2] [pmid]
  • Morton JF (1962a) Ornamental plants with toxic and/or irritant properties. II. Proceedings of the Florida State Horticultural Society 75: 484-491 [url] [url-2]
  • Nadkarni AK (1976) Dr. K. M. Nadkarni's Indian Materia Medica. With ayurvedic, unani-tibbi, siddha, allopathic, homeopathic, naturopathic & home remedies, appendices & indexes, Revised enlarged and reprinted 3rd edn, Vols 1 & 2. Bombay: Popular Prakashan [WorldCat] [url]
  • Nishigori C, Aoyama Y, Ito A, Suzuki K, Suzuki T, Tanemura A, Ito M, Katayama I, Oiso N, Kagohashi Y, Sugiura S, Fukai K, Funasaka Y, Yamashita T, Matsunaga K (2015) Guide for medical professionals (i.e. dermatologists) for the management of Rhododenol-induced leukoderma. The Journal of Dermatology 42(2): 113-128 [doi] [url] [url-2] [pmid]
  • Pardo Costello, V. and Reaud, B. (1941) Eczemas y dermatitis. Anais Bras. de Dermat. e Sifilog 17(l): 11.
  • Piffard HG (1881) A Treatise on the Materia Medica and Therapeutics of the Skin. New York: William Wood & Company [WorldCat] [url] [url-2]
  • Quisumbing E (1951) Medicinal Plants of the Philippines. Technical Bulletin 16, Philippines Department of Agriculture and Natural Resources. Manila, Philippine Islands: Manila Bureau of Printing [WorldCat]
  • Remington JP, Wood HC, Sadtler SP, LaWall CH, Kraemer H, Anderson JF (Eds) (1918) The Dispensatory of the United States of America. 20th edn. Philadelphia: JB Lippincott [WorldCat] [url] [url-2]
  • Santamour FS, Lundgren LN (1997) Rhododendrin in Betula: a reappraisal. Biochemical Systematics and Ecology 25(4): 335-341 [doi] [url]
  • Santamour FS, Vettel HE (1978) The distribution of Rhododendrin in birch (Betula) species. Biochemical Systematics and Ecology 6(2): 107-108 [doi] [url]
  • Sasaki M, Kondo M, Sato K, Umeda M, Kawabata K, Takahashi Y, Suzuki T, Matsunaga K, Inoue S (2014) Rhododendrol, a depigmentation-inducing phenolic compound, exerts melanocyte cytotoxicity via a tyrosinase-dependent mechanism. Pigment Cell & Melanoma Research 27(5): 754-763 [doi] [url] [url-2] [pmid]
  • Schwartz, L., Tulipan, L. and Birmingham, D.J. (1957) Occupational Diseases of the Skin. 3rd edn. Philadelphia. Lea and Febiger. pp. 637-672.
  • Seaton A, Morgan WKC (1984) Hypersensitivity pneumonitis. In: Morgan WKC, Seaton A (Eds) Occupational Lung Diseases. 2nd edn, pp. 564-608. Philadelphia: WB Saunders Co. [WorldCat]
  • Smith, F.P. (1969) Chinese Materia Medica. Vegetable kingdom. 2nd edn. Rev. by Hei, P.D. Taipei, Taiwan. Ku T'ing Book House.
  • Standing Committee on Cosmetic Products (2019) Commission Decision (EU) 2019/701 of 5 April 2019 establishing a glossary of common ingredient names for use in the labelling of cosmetic products. Official Journal of the European Union 62(L 121): 1-370 [url] [url-2]
  • Todd RG (Ed.) (1967) Martindale. The Extra Pharmacopoeia. 25th edn. London: Pharmaceutical Press [WorldCat]
  • Watt JM, Breyer-Brandwijk MG (1962) The Medicinal and Poisonous Plants of Southern and Eastern Africa. Being an account of their medicinal and other uses, chemical composition, pharmacological effects and toxicology in man and animal, 2nd edn. Edinburgh: E & S Livingstone [doi] [WorldCat] [url] [url-2]
  • Webb LJ (1948a) Guide to medicinal and poisonous plants of Queensland. Commonwealth Scientific and Industrial Research Organisation. Bulletin 232
  • Weber LF (1953) Dermatitis venenata due to native woods. AMA Archives of Dermatology and Syphilology 67(4): 388-394 [doi] [url] [url-2]
  • Wehmer, C. (1929) Die Pflanzenstoffe. Verlag G. Fischer. Jena. 2. Aufl.
  • Wodehouse RP (1971) Hayfever Plants. Their appearance, distribution, time of flowering, and their role in hayfever, 2nd revised edn. New York, NY: Hafner Publishing Company [WorldCat]
  • Wren RC (1975) Potter's New Cyclopaedia of Botanical Drugs and Preparations. (Re-edited and enlarged by Wren RW). Bradford, Devon: Health Science Press [WorldCat] [doi] [url] [url-2]

Richard J. Schmidt

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