Poison ivy, Rhus

Allergenic plants causing skin eruption by contact include poison ivy (Rhus radicans L.), poison oak (Rhus toxicodendron L.), poison sumac (Rhus vernix L.), and stinging nettle (Urtica dioica L.). In the United States, poison ivy and poison oak cause nearly 2 million cases of skin poisoning and skin irritation annually, for a loss of 333,000 working days. In addition, these weeds cause 3.7 million days of restricted activity among those people who are susceptible to the toxins (1). 

As the free sugar in small amounts in wine and in the extract of the leaves of poison ivy (Rhus toxidendmn), and in some microbial polysaccharides... 

Ginkgolic acids are urushiol type alkylphenols, related to compounds in poison ivy Rhus toxicodendron), and are associated with contact allergic responses, especially dermatitis. Ginkgolic acids are found in relatively high concentrations in ginkgo seed coats and in lower concentrations in ginkgo leaf (Blumenthal 1997). 

Kligman AM (1958) Poison ivy (Rhus) dermatitis. Arch Dermatol 77 149-180... 

Occurrence 109), The sugar is a frequent constituent of glycosides, which provide its best source. It may occur 110) in the free state in the leaves and blossoms of the poison ivy, Rhus toxicodendron L. Some polysaccharides of gums and mucilages contain L-rhamnose. The sugar also has been detected in various immunological polysaccharides of bacterial origin 111),... 

Other significant phenolic resin compounds include the mixture of urushiol variants, immunogenic compounds causing severe dermatitis from the Rhus spp. (poison ivy, poison oak and poison sumac). 

Poison oak Rhus toxicodendron or Toxicodendron toxicaria Anacardiaceae) is nearly always found as a low-growing shrub, and has lobed leaflets similar to those of oak. It is also common throughout North America. There appears considerable confusion over nomenclature, and Rhus radicans may also be termed poison oak, and R. toxicodendron oakleaf poison ivy. Poison oak contains similar urushiol structures in its sap as poison ivy, though heptadecylcatechols (i.e. C17 side-chains) predominate over pentadecylcatechols (C15 side-chains). 

Rhus Radicans Common Names Poison Ivy, Poison Oak Poison Urushiol Dosage ioz(28G)Oil... 

Dihydric phenolic lipids are the most abundant phenolic lipids. They are of the cardol-or urushio 1-type, i.e. with hydroxyl groups in the metha position (1,3-dihydroxy) or in the ortho (1,2-dihydroxy) position respectively. Urushiol-type, dihydroxy phenolic lipids, are practically restricted to the Anacardiaceae family (Rhus genus) of poisonous plants. The most well-known are poison ivy, poison oak and the Indian marking nut. The sap from various plants belonging to Anacardiaceae from which Japanese, Chinese, Burmese, Formosan and Vietnamese lacs is one of the richest source of these phenols. The occurrence of dihydric phenolic lipid of the urushiol type is depicted in Table 3. 

Rhus toxicodendron Poison ivy Urushiol As for Japanese lac except (27) absent 26 N. America... 

Urushiol yu- rii-she- 61, ii-, - ol [ISV, fr. Japanese urushi lacquer -f ISV -ol] (1908) n. A mixture of pyrocatechol derivatives with saturated or unsaturated side chains of 15 or 17 carbon atoms that is an oily toxic irritant principle present in poison ivy and some related plants (genus Rhus) and in oriental lacquers derived from such plants. Langenheim JH (2003) Plant resins chemistry, evolution ecology and ethnobotany. Timber Press, Portland, OR Paint pigment, drying oils, polymers, resins, naval stores, cellulosics esters, and ink vehicles, vol 3. American Society for Testing and Material, Conshohocken, PA, 2001. 

Rhus dermatitis from poison ivy, oak and sumac (onycholysis, yellowish discoloration of the nail) (Fulghum 1972)... 

Machaerium scleroxylon) in a hobbyist handling the wood. Plants reported to cause erythema multiformelike eruption include poison ivy (Toxicodendron) (Schwartz and Downham 1981 Mallory et al. 1982), primula Primula obconica) (Hjorth 1966) and mug-wort (Artemesia vulgaris) (Kurz and Rapaport 1979). Mallory et al. (1982) reported urticarial eruptions with black deposits on the skin of four patients with Toxidocendron radicans dermatitis. Urticaria, erythema multiforme-like eruptions, in a patient from Rhus dermatitis was reported by Schwartz and Down-ham (1981). They recommended that patients with such reactions should be screened for systemic involvement as previous reports have shown that nephritis can be an associated feature (Meneghini and AngeUni 1981 Fisher 1986). 

McNair JB (1923) Rhus dermatitis from Rhus toxicodendron radicans and diversibola (poison ivy). Its pathology and chemotherapy. University of Chicago Press, Chicago, pp 56-71... 

Rademaker M, DuffiU MB (1995) Toxicodendron succeda-neum Rhus tree). New Zealand s poison ivy. Contact Dermatitis 33-357-358... 

The Rhus plants, which include poison ivy, oak, and sumac, and contain the allergen urushiol, are the most common cause of allergic contact dermatitis in North America, affecting 50% or more of the population (Bergfeld and Elston 1994 Lowell 1996). A vast array of plants, including primrose and Compositae, cause contact dermatitis, airborne dermatitis, contact urticaria, and phytodermatitis, and are a potential threat to athletes participating in outdoor sports. 

Pentadecylcatechol is the main allergen of the Ana-cardiaceae poison ivy Toxicodendron radicans) and of poison oak Toxicodendron diversilobay Rhus diversi-loba). 

The simple diphenol, pentadecylcatechol, is the major constituent of the irritant oils from Rhus and Toxicodendron spp. (see Chap. 7.1). It appears to be ubiquitously troublesome to the general public in poison ivy, oak, sumac, and the lacquer tree (57). It is only moderately troublesome to woodworkers because only... 

L-Rhamnose Branched sugar 94° hydrate +9° Benzoyl- hydrazone 186° Leaves Rhus toxicodendron (poison ivy) Glycosides, gums, mucilages, bacterial and algal polysaccharides... 

Concurrently, the Egyptians, Japanese, and Chinese were beginning to develop lacquers (Stillman, I960). Some time before 200 b.c., the Chinese used the exudation (sap) from the conifer Rhus vemicifera (which became known as the sumac or varnish tree) as a coating. This plant has also been called the urushi tree. The tree belongs to the same family as the poison ivy plant, and like it, all parts of the tree are toxic— tree, sap, and latex. Those who tap the tree must wear gloves and protective clothing. The active irritant is urushiol, a catechol derivative. 

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