Calcium sulfate

Synonyms

Anhydrous calcium sulfate; Anhydrous gypsum; Anhydrous sulfate of lime; Calcium salt of sulfuric acid [NIOSH] Anhydrous calcium sulfate; Anhydrous sulfate of lime; Gypsum; Plaster of Paris; Drierite; [ACGIH]

Category

Other Mineral Dusts

Description

Odorless, white powder or colorless, crystalline solid. [Note: May have blue, gray, or reddish tinge; [NIOSH]

Sources/Uses

Gypsum is the dihydrate form and Plaster of Paris is the hemihydrate form. [NIOSH] Used in cement and paper filler (insoluble anhydrite), in a drying agent (soluble anhydrite), in wall plaster and wallboard (hemihydrate), and in soil treatment, Plaster of Paris, Portland cement, water clarification, animal feed, and calcium supplements in food (dihydrate gypsum); The natural forms are the mineral anhydrite (CaSO4) and the dihydrate, gypsum (CaSO4 . 2H2O). [ACGIH]

Comments

TLV based on "nasal symptoms." Calcium sulfate is a "relatively non-toxic substance." "Human epidemiologic studies were lacking in exposure information or were confounded by quartz exposure." [ACGIH] See "Calcium sulfate dihydrate."

Reference Link #1

Biomedical References

Insufficient data

10 mg/m3, inhalable fraction

15 mg/m3(total dust), 5 mg/m3(respirable fraction)

4 mg/m3(inhalable fraction), 1.5 mg/m3(respirable fraction)

Processes

Industrial Processes with risk of exposure:

• Cement Producing
• Farming (Feed Additives)
• Mining