Calcium, carbonate hydroxy aluminum complexes

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

repeated dose toxicity: inhalation

Remarks:

combined repeated dose and carcinogenicity

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

review article or handbook

Title:

Recommendation from the Scientific Committee on Occupational Exposure Limits for Calcium oxide (CaO) and calcium hydroxide (Ca(OH)2)

Author:

Scientific Committee on Occupational Exposure Limits

Year:

2008

Bibliographic source:

SCOEL/SUM/137, February 2008

Materials and methods

Test guideline

Qualifier:

no guideline available

Guideline:

other: Repeated studies in human

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Calcium oxide

EC Number:

215-138-9

EC Name:

Calcium oxide

Cas Number:

1305-78-8

IUPAC Name:

oxocalcium

Constituent 2

Reference substance name:

Calcium dihydroxide

EC Number:

215-137-3

EC Name:

Calcium dihydroxide

Cas Number:

1305-62-0

IUPAC Name:

calcium dihydroxide

Constituent 3

Reference substance name:

Portland cement

IUPAC Name:

Portland cement

Test animals

Species:

other: Human

Administration / exposure

Route of administration:

inhalation: dust

Type of inhalation exposure:

whole body

Results and discussion

Effect levels

Dose descriptor:

NOAEL

Effect level:

ca. 1 mg/m³ air

Based on:

test mat.

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

The Scientific Committee on Occupational Exposure Limits defined an 8 hour TWA (Time Weighted Average) for Calcium hydroxide of 1 mg/m3 with a STEL (Short Term Exposure Limit) of 4 mg/m3 for 15 minutes.
This leads to an OEL for CAHC of 2.5 mg/m³ with a STEL of 10 mg/m³

Executive summary:

The effects of Calcium hydroxide are considered to be limited to the external surface of the body and no systemic effects are foreseen.Assuming an exposure level of 1 mg/m³and an inhalation of 10 m³of air during an 8-hour workday, this would result in an inhaled dose of 5.4 mg calcium per day. Overall, the occupational exposure would only increase the body burden of calcium to a negligible extent as the Tolerable Upper Intake Level is 2,500 mg of calcium per day.

At low-level exposures, sensory irritation and a decrease of the lung function parameters at long-term exposures are considered to be the critical effects.From a well conducted acute human study with Calcium oxide, sensory irritation is expected to be avoided at 1 mg/m³of respirable dust. No relevant respiratory effects were seen at an exposure level of 1 mg/m³of total dust among kiln workers producing. One mg of Calcium hydroxide per m³ is therefore obviously protective against adverse effects from long-term exposure to Calcium hydroxide and this concentration is supported by data from exposure to cement dust that has a similar alkalinity.

The Scientific Committee on Occupational Exposure Limits defined an 8 hour TWA (Time Weighted Average) for Calcium hydroxide of 1 mg/m3 with a STEL (Short Term Exposure Limit) of 4 mg/m3 for 15 minutes.

This leeds to an OEL for CAHC of 2.5 mg/m³ with a STEL of 10 mg/m³