Hevea brasiliensis latex, natural sources

Allergy to natural rubber latex, first reported in 1989 in the United States, is a common cause of occupational allergy for health care workers. Natural rubber is a processed plant product from the commercial rubber tree, Hevea brasiliensis. Latex allergens are proteins found in both raw latex and the extracts used in finished rubber products. Latex gloves are the largest single source of exposure to the protein allergens. ... 

We begin with two trees, both cultivated on plantations in Southeast Asia. One, Hevea brasiliensis, is a source of natural rubber and was innported from Brazil in the nineteenth century. The other, Isonandra gutta, is native to Sumatra, Java, and Borneo and gives a latex from which gutta-percha is obtained. 

Siler, D. X, Cornish, K., Hamilton, R. G. Absence of cross-reactivity of IgE antibodies from subjects allergic to Hevea brasiliensis with new sources of natural rubber latex from guayule (Parthenium argentatum). J. Allergy Clin. Immunol. 1996, 98, 895-902. 

Renewable raw materials are made or derived from short-term renewable sources (one to a few years or a few tens of years) such as plants, trees, wood wastes and other agricultural products. Not all these materials are necessarily biodegradable. Natural rubber, for example, comes from the latex of a tree (Hevea brasiliensis) and is not biodegradable. Renewable materials are often considered as opposites to fossil sources such as petroleum that are not renewable on a human timescale. On the other hand, some synthesized plastics such as certain polyesters are biodegradable. 

Natural rubber latexes occur in many plants. The white sap of the common milkweed and dandelion is a rubber latex. The most important source of natural rubber latex is the Hevea brasiliensis tree, now grown in plantations in many tropical parts of the world. 

Rubber is a naturally occurring diene polymer of isoprene (2-methyl-l,3-butadiene) and is produced by more than 400 different plants. The major source is the so-called mbber tree, Hevea brasiliensis, from which the cmde material, called latex, is harvested as it drips from a slice made through the bark. The double bonds of rubber have Z stereochemistry, but gutta-percha, the E isomer of mbber, also occurs naturally. Harder and more brittle than mbber, guttapercha has a variety of minor applications, including occasional use in dentistry and as the covering on golf balls. 

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