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Talc Hazards Overview
Health concerns about talc revolve mainly around the non-platiform content, the extent to which these are asbestos, and how high the length:width ratio of non-asbestos particles needs to be to make them a hazard also.
ACGIH TLV and OSHA PEL: 2 mg/cubic meter, 8 hr. TWA, Respirable Dust (talc containing no asbestos fibers).
CAS: 71949-90-1
Chlorite (typical 3%) ACGIH TLV: 10 mg/cubic meter 8 hr. TWA
CAS: 14808-60-7 Silica: (typical 2%) ACGIH TLV & OSHA PEL: 0.1 mg/cubic meter 8 hr. TWA, Respirable Dust
Wilson's RISK Scale of Material Hazards
(1-4 higher numbers are increased hazard)
R 1 (reactivity)
I 2 (inhalation)
S 1 (skin contact)
K 1 (kindling/fire)
May cause irritation to upper respiratory tract.
Pre-existing lung disease may be aggravated by exposure to dust.
Prolonged over exposure can cause Talcosis (a pulmonary fibrosis of the lungs). Although talc is a fibrous magnesium silicate as is asbestos, it does not have the same effect on the lungs. The two minerals are closely associated, and most commercial talcs do contain some asbestos.
Talc is not characterized as a carcinogen by NTP, IARC, ACGIH or OSHA.
Talc may contain extremely small amounts (less than 2 ppm) of substances regulated under drinking water regulations: e.g. arsenic, beryllium, cadmium, chromium, lead, mercury, nickel.
Phsyical Data:
Water Solubility: Insoluble
Specific Gravity: 2.5-2.8
Melting Point: 1650-1830F (900-1000F)
Flash Point: Non-combustible
Hazardous Decomposition Products: None
Stability: High resistant to acids, alkalies, heat.
Disposal: Talc is not a hazardous waste.
An excellent discussion of talc hazards can be found in 'Documentation of the Threshold Limit Values and Biological Exposure Indices' from the American Conference of Industrial Hygienists, Cincinnati, OH
'Patty's Industrial Hygiene and Toxicology', John Wiley & Sons has information on asbestosis and talcosis. Out Bound Links
- (URLs)
Asbestos at ilo.org
http://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc00/icsc0014.htm - (Hazards)
Talc Toxicology
Hazards of this material in the ceramic industry and process - (URLs)
Asbestos at Wikipedia
http://en.wikipedia.org/wiki/Asbestos
In Bound Links
By Tony Hansen    | 