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Coal tar wikipedia Tar is a general disinfectant. Tar made from coal or petroleum is considered toxic and carcinogenic because of its high benzene content, [citation needed] though coal tar in low concentrations is used as a topical medicine for conditions such as psoriasis. In addition to toxicity to fungi, insects, and marine borers, it serves as a natural water repellent. Petroleum tar was also used in ancient Egyptian mummification circa 1000 BC. Tar is used in treatment of the skin disease psoriasis, where coal tar is the most effective. [13]Coal tar is a mixture of approximately 10,000 chemicals, of which only about 50% have been identified. Coal tar is produced through thermal destruction of coal. [11] [12] Coal and petroleum tar has a pungent odor. Tar was a vital component of the first sealed, or "tarmac", roads. Coal-tar creosote is the most widely used wood treatment today; both industrially, processed into wood using pressure methods such as "full-cell process" or "empty-cell process", and more commonly applied to wood through brushing. Coal tar is listed at number 1999 in the United Nations list of Created by William Valentine Wright in 1860, Wright's Coal Tar Soap is a British brand of antiseptic soap designed to cleanse the skin thoroughly. Its composition varies with the process and type of coal used – lignite, bituminous or anthracite. Goeckerman regimens use crude coal tar, which contains polycyclic aromatic hydrocarbon, a carcinogen. For over 150 years, Wright's Coal Tar Soap was a popular brand of household soap; its successor, Wright's Traditional Soap, can still be bought in supermarkets and from The production of coke from coal produces ammonia, coal tar, and gaseous compounds as byproducts which if discharged to land, air or waterways can pollute the environment. [152] The Whyalla steelworks is one example of a coke producing facility where liquid ammonia was discharged to the marine environment. It is an orange colour. [8] [9] However, Goeckerman therapy is considered safe although use of tar may have the side-effects of contact dermatitis and mild local burning due to tar hypersensitivity. . dcq mvzak ruga bxgsup puaes ehbwqogd yaoan qnke gkvzj oqai |
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