Document 2jNxm7K4n8QwDqMJ0gV8NV8ML

ELEMENTS OF INDUSTRIAL TOXICOLOGY and in man However, it seems highly un likely that this will ever become a common disease of man because of the severe irrita tion involved in inhaling even a very small concentration The highest concentration producing no deaths m adult guinea pigs for an fi-hr exposure was 20 mg per cu m See Industrial Data Sheet 325 and Hy gienic Guide Sulfur monochlonde is still used to some extent as a vulcanizing agent in die rubber industry It is a dark yellow, highly vola tile liquid, which hydrolyzes rapidly in moist air to give hydrogen chlonde, sulfur diox ide, and sulfur. Its extremely irritating ef fect on the skin, eyes, and respiratory sys tem is due primarily to the hydrochloric acid formed in its hydrolysis The chemical is commonly dissolved in carbon disulfide which has no irritating or warning properties and is therefore much more hazardous both to health and to safe ty than sulfur monochlonde Sulfur pentafluonde is an extremely toxic material In experiments on rats, 10 ppm caused lung irritation in a one-hr exposure, for an exposure of 18 hr, 0 1 ppm caused lung irritation and 1 0 ppm was lethal For an 18-hr exposure, 001 ppm had no ob servable effect Talc, as used in industry, covers a wide variety of materials, many of which are not talcs at all The only one which has been specifically suggested as the cause of a pneu moconiosis is tremokte talc, a hydrous mag. nesnim silicate occurring u needlehke form and rather closely related to asbestos It is, however, only slightly active because the exposures cited have been to heavy air con tamination for many years Talc has been demonstrated to produce granulomas when deposited in the body, and for that reason has been dropped from sur gical use One pulmonary case also showed granuloma and fibrosis apparently produced by the inhalation of talc used as a lubricant on patent leather See Chapter 39, "Industrial Hygiene" and Industrial Data Sheet 531 for discussions of talcosis. Tar and pilch have been known for a great many years, particularly in England, as producers of skin cancer. The slon can cer of chimney sweeps is undoubtedly due to the tar fraction of the soot with which they work Sian cancers of mule spinners were next reported when mineral oil was substituted for vegetable oil or whale oil in the spinning industry High incidence of skin cancer among men exposed to oils, tar, or pitch has not been reported from the European continent or from the United States, although in both areas there have been several extensive investigations of this question. Teflon resms are available in two types the TFE resin (tetrailuoroethylene poly mer) and the FEP resin (fluonnated ethy lene-propylene polymer) Both are physio logically inert The products of pyrolysis of Teflon below 392 F (200 C) are nonhazardous, but above this temperature, several fluorocarbon gases, hydrogen fluonde, and a sublimate are formed These do not ap pear to be toxicologically significant until about 482 F (250 C). At 716 F (380 C), small amounts of toxic gases, which have caused death by pulmonary edema in experimental animals, ate evolved. The only known difficulty m human exposure has occured when Teflon resms are processed at 644-725 F (340380 C) At these temperatures, a condition somewhat like metal fume fever is exhibit ed, but recovery is rapid, usually in 48 hours or less All operations that can lead to the pyrolysis of Teflon resins should therefore be prohibited, particularly smoking where the tobacco may be contaminated with Teflon dusts. See Hygtemc Gt/tde. Tellurium is found as a trace element in various minerals and is used m small amounts in a number of industries, especial ly the glass industry It increases the machinabibty of some metals and improves the toughness of rubber hose and cable and the hairiness of lead In man, the absorption of even a very small amount of tellurium in any form is immediately followed by the production of a garlicky odor m the breath and the sweat, due to the elimination of minute amounts of tellurium as methyl teliunde This elimina tion Is likely to continue for weeks or months. Hydrogen teliunde, a poison gas simi lar to arsine and hydrogen selemde, destroys 4034