Sulfuric acid, mono(C16-18 and C18-unsatd. alkyl) esters, sodium salts

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

There is no study regarding skin sensitisation with C16-18 and 18 unsaturated AS Na (CAS 1394155-71-5) available. Therefore this endpoint is covered by read across to structurally related alkyl sulfates (AS), i.e. C12-18AS Na (CAS 68955-19-1). The possibility of a read-across to other alkyl sulfates in accordance with Regulation (EC) No 1907/2006 Annex XI 1.5. Grouping of substances and read-across approach was assessed. In Annex XI 1.5 it is given that a read-across approach is possible for substances, whose physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity. The AS reported within the AS category show structural similarity. The most important common structural feature of the category members is the presence of a predominantly linear aliphatic hydrocarbon chain with a polar sulfate group, neutralized with a counter ion. This structural feature confers the surfactant properties of the alkyl sulfates. The surfactant property of the members of the AS category in turn represent the predominant attribute in mediating effects on mammalian health. Therefore, the AS of the AS category have similar physico-chemical, environmental and toxicological properties, validating the read across approach within the category. The approach of grouping different AS for the evaluation of their effects on human health and the environment was also made by the OECD in the SIDS initial assessment profile [1] and by a voluntary industry programme carrying out Human and Environmental Risk Assessments (HERA [2]), further supporting the read across approach between structurally related AS.

There is one relevant study available addressing skin sensitisation for the read-across substance C12-18AS Na (CAS 68955-19-1).

The skin sensitizing potential of C12-18AS Na (CAS 68955-19-1) was assessed in a Buehler Test according to OECD Guideline 406 under occlusive conditions (Hoyer, 1996). In this study, 20 guinea pigs of the treatment group were induced three times via epicutaneous application of a 12.5% aqueous solution of the test item for 6 h at an interval of 7 days. The procedure was also performed on 10 animals of the control group with water as inducing agent. Challenge was performed 7 days after the last induction treatment for 6 h at a concentration of 6.25% on all animals (treated and control). Animals of the control group were also challenged with water on the opposite flank. Each challenge site was examined 24 and 48 h after removal of the challenge patch. At the 24 h readin,g skin reactions of the control group were observed on 2/10 (20%) guinea pigs at the site challenged with the test item. Skin reactions were also observed on one of these animals on the site challenged with water (10%). No skin reaction was observed at the second reading on any animal of the control group. Skin reactions were seen in 4/20 (20%) animals after 24 h and on 2/20 (10%) animals after 48 h in the treatment group. Thus, C12-18AS Na (CAS 68955-19-1) is not a skin sensitiser. Another alkyl sulfate, i.e. sodium lauryl sulphate (C12AS Na) is recommended as an agent to induce local irritation in a method to assess skin sensitising properties of chemicals (OECD guideline 406, Guinea Pig Maximisation Test). Therefore there is a lot of experience with sodium lauryl sulfate in sensitising studies and no evidence occured that it shows sensitising properties. Thus, skin sensitisation by members of the alkyl sulfates is generally unlikely.

 

[1] SIDS initial assessment profile, (2007);
http://www.aciscience.org/docs/Alkyl_Sulfates_Final_SIAP.pdf

[2] (HERA Draft report, 2002);
http://www.heraproject.com/files/3-HH-04-%20HERA%20AS%20HH%20web%20wd.pdf

Migrated from Short description of key information:
Skin sensitisation (Buehler test - OECD 406): not sensitising

Justification for selection of skin sensitisation endpoint:
Reliable OECD guideline study.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The available data on skin sensitisation do not meet the criteria for classification according to Regulation (EC) 1272/2008 or Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.

No data available for respiratory sensitisation.