(1-hydroxyethane-1,1-diyl)bis(phosphonic acid), compound with 2-aminoethanol (1:[?])

Endpoint summary

Description of key information

An OECD 439 skin irritation study was performed and showed no skin irritation potential in the EpiDerm model.

An OECD 431 skin corrosion study was performed and showed no skin corrosion potential in the EpiDerm model.

An OECD 437 study was performed and showed serious eye irritation in the EpiOcular model.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

The objective was to assess the skin irritation and corrosion potential of the waterfree test item. By using the currently available methods a single in vitro assay is not sufficient to cover the full range of skin irritating/corrosion potential. Therefore, two in vitro assays were part of this in vitro skin irritation and corrosion test strategy: The Skin Corrosion Test (SCT) and Skin Irritation Test (SIT).

The test substance is not able to directly reduce MTT. The final mean viability of the tissues treated with the test substance determined after an exposure period of 3 minutes was 94.1% and it was 75.6% after an exposure period of 1 hour.

In total four test runs were performed. However the third test run is considered invalid and is not reported.

1st test run:

The final mean viability of the tissues treated with the test substance determined after an exposure period of 1 hour with an about 42-hour post-incubation was 54.0%. However, due to

the non-concordant replicate measurements of the test-substance treated tissues obtained (relative viability values for individual values: 76.5%, 75.9% and 9.4%), a 2nd test run was

performed to clarify the result.

2nd test run:

The final mean viability of the tissues treated with the test substance was 68.0%. However, due to the non-concordant replicate measurements of the test-substance treated tissues

obtained in the 2nd test run (relative viability values for single values: 77.1%, 64.3% and 40.8%), a 3rd test run was performed to clarify the result.

4th test run:

Due to technical issues at removal of the test substance during the 3rd run of the skin irritation test the test substance was applied without a metal pin in the 4th test run. A bulk volume of

ca. 25 μL of the undiluted test material was formed to a flat “disc like piece” of ca. 8 mm diameter and placed atop the tissues.

The final mean viability of the tissues treated with the test substance for the 4th test run was 85.3% (relative viability values for single tissues: 96.2%, 76.7% and 83.2%). All acceptance

criteria were met. Overall, the viability values of the most tissues (valid test runs) and all tissues in the 4th run are well above the cut off for skin irritation, thus it was concluded that the test substance does not indicate an irritation potential.

The objective was to assess the eye irritating potential of the test item. By using the methods currently available a single in vitro assay is not sufficient to cover the full range of eye irritating potential. Therefore, two in vitro assays were part of this in vitro eye irritation test strategy: The Bovine Corneal Opacity and Permeability Test (BCOP Test) and EpiOcular Eye Irritation Test.

The potential of the test substance to cause serious damage to the eyes was assessed by a single topical application of 750 μL of a 20% test-substance preparation to the epithelial surface of isolated bovine corneas. Three corneas were treated with the test-substance preparation for an exposure period of 4 hours. The mean opacity value obtained for the test material was 0.0, the mean permeability value was 0.001. The IVIS of the substance is therefore 0.0.

The potential of the test substance to cause ocular irritation was assessed by a single topical application of ca. 50 μL bulk volume (about 60 mg) undiluted test substance to a reconstructed three-dimensional, human cornea model (EpiOcular™).

Two EpiOcular™ tissues per test run were incubated with the test substance for 6 hours followed by a 18-hour post-incubation period. The final mean viability of the tissues treated with the test substance was 32.4% (values for individual tissues: 25.8% and 39.9%).

Based on the results of the BCOP and EpiOcular Tests the test item shows an eye irritation potential in the in vitro eye irritation test strategy under the test conditions chosen.

Justification for classification or non-classification

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008.

As a result the substance is not considered to be classified as skin irritant and considered to be classified for causing serious eye irritation under Regulation (EC) No. 1272/2008.