Portland cement

Synonyms

Cement; Hydraulic cement; Portland cement silicate; [NIOSH]

Category

Other Mineral Dusts

Description

Gray, odorless powder; [NIOSH]

Sources/Uses

A class of hydraulic cements containing tri- and dicalcium silicate in addition to alumina, tricalcium aluminate, and iron oxide; [NIOSH] Finished cement contains silicate compounds, but little or no quartz. [ACGIH] Crystalline silica not bound to other minerals is "free" silica. Silicates are minerals in which silicon and oxygen are combined with other elements. [Rom, p. 364]

Comments

Chromium is a major cause of allergic contact dermatitis among workers handling cement, particularly those manufacturing prefabricated concrete building units. Samples of American cement contained 5 to 124 ppm chromium content, while European samples contained 32 to 176 ppm. Wet cement can also cause irritant dermatitis and third degree burns after prolonged skin contact. [Marks, p. 273] Regarding potential adverse effects on the lung, "Portland cement dust is considered to have little potential to induce adverse effects on the lung such as pneumoconiosis or fibrosis." [ACGIH] A cross-sectional study of 126 production workers in Tanzania showed a significant relationship between cumulative cement dust exposure and FVC/FEV1 pulmonary function measurements. "A significant risk for developing COPD is found for those working for more than 10 years at 10 mg/m3." The authors noted the recent negative studies of cement workers in the USA, Jordan, Taiwan, and Norway where dust exposures were low compared to those in Tanzania. [Reference #1] Wet cement causes alkaline burns as calcium oxide reacts and makes calcium hydroxide. [Reference #2] "Quartz and chromate fractions must be evaluated as such (valid only for low-chromate cement containing < 2 ppm of Cr(VI). See the Cr(VI) cmpds for cement with a higher Cr(VI) content.)" [MAK]

The EU regulates soluble chromium in cement to a maximum of 0.0002% to prevent allergic contact dermatitis. [van der Molen HF, et al. World at work: Bricklayers and bricklayers' assistants. Occup Environ Med 2004;61:89-93]

Reference Link #1

Biomedical References

Insufficient data

1 mg/m3 (respirable fraction)

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

5000 mg/m3

Excerpts from Documentation for IDLHs

Basis for revised IDLH: The available toxicological data contain no evidence that an acute exposure to a high concentration of Portland cement would impede escape or cause any irreversible health effects within 30 minutes. However, the revised IDLH for portland cement is 5,000 mg/m3 based on being 500 times the NIOSH REL of 10 mg/m3 (500 is an assigned protection factor for respirators and was used arbitrarily during the Standards Completion Program for deciding when the "most protective" respirators should be used for particulates).

Reference Link #2

Yes

Yes

Skin burns

Not Classifiable

Diseases

Occupational diseases associated with exposure to this agent:

• Contact dermatitis, allergic
• Pulmonary disease, chronic obstructive

Processes

Industrial Processes with risk of exposure:

• Cement Producing