Hafnium and compounds

Synthetic graphite injected peritoneally in mice produces a reaction characteristic of an inert material. On the basis of experimental evidence, and the rarity of reports of adverse effects of exposure in humans, it is concluded that pure synthetic graphite acts only as an inert dust. 

The 2003 ACGIH threshold limit valuetime-weighted average (TLV-TWA) for synthetic graphite (except graphite fiber) is 2 mg/m  

Lister WB, Wimborne D Carbon pneumoconiosis in a synthetic graphite worker. Br J Ind 

Hanoa R Graphite pneumoconiosis. A review of etiologic and epidemiologic aspects. ScandJ Work Environ Health 9 303-314, 1983 

Petsonk EL Pneumoconiosis in carbon electrode workers. J Occup Med 30 887-891, 1988 

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