Title:  Talc 
CAS Registry Number:  14807-96-6 
Additional Names:  Talcum;  French chalk 
Literature References:  The lumps are also known as soapstone or steatite.  Finely powdered native hydrous magnesium silicate.  Comprehensive description:  A. W. Newman et al., Anal. Profiles Drug Subs. Excip. 23, 511-542 (1994). 
Properties:  White to grayish-white, very fine odorless, crystalline powder; unctuous, and adheres readily to the skin.  Insol in water, cold acids or in alkalies.  Sol in hot concentrated phosphoric acid. 
CAUTION:  Potential symptoms of overexposure to talc containing no asbestos and less than 1% quartz are fibriotic pneumoconiosis; irritation of eyes.  Potential symptoms of overexposure to soapstone containing less than 1% quartz are pneumoconiosis; cough, dyspnea; digital clubbing; cyanosis; basal crackles, cor pulmonale.  See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 292, 280. 
Use:  Dusting powder, either alone or with starch or boric acid, for medicinal and toilet prepns; excipient and filler for pills, tablets and for dusting tablet molds; clarifying liquids by filtration.  As pigment in paints, varnishes, rubber; filler for paper, rubber, soap; in fireproof and cold-water paints for wood, metal and stone; lubricating molds and machinery; glove and shoe powder; electric and heat insulator.   |