sulfuric acids, C9-11-iso-C10 rich, alkyl esters, sodium salt

Endpoint summary

Description of key information

No data are available for the target substance Sulfuric acids, C9-11-iso-C10 rich, alkyl esters, sodium salt. Therefore, read-across from structural analogue substances has been applied.

Skin sensitisation (LLNA - OECD 429): not sensitising

Read-across from structural analogue source substances Sodium octyl sulfate (CAS 142-31-4) and Sodium dodecyl sulfate (CAS 151-21-3)

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Reference 1

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

yes

Remarks:

Only limited data on test item and methodology available

Principles of method if other than guideline:

Method: other

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

-Source: Jackson Labs., ME
-Age: ca. 5 weeks
-Weight at study initiation: 12 - 20 g

Vehicle:

other: water

Concentration:

12.5 µl of a 10, 50 or 100% solution

No. of animals per dose:

5

Details on study design:

TREATMENT PREPARATION AND ADMINISTRATION:
-Daily topical application of 12.5 µl of a 10, 50 or 100% solution in dist. water on 4 consecutive days -Ca. 21 hrs. after last treatment the animals were injected i.v. with radiolabeled thymidine. Approximately 5 h after injection the mice were euthanized, the auricular lymph nodes were removed and single cell suspensions were prepared. Cells were washed with phosphate-buffered saline to remove unbound radiolabel, then precipitated with trichloroacetic acid. The total radiolabel incorporation in these precipitates was subsequently quantified by liquid scintillation spectrometry.

Parameter:

SI

Value:

1.25

Remarks on result:

other: 1.25, 2.7 or 3.1

Parameter:

SI

Value:

2.7

Parameter:

SI

Value:

3.1

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: No data available

The treatment had no significant effect on thymidine incorporation by 

auricular lymph node cells when compared with naive and carrier controls:

stimulation index: 1.25, 2.7 or 3.1
naive control: 2.4
carrier control: 1

Interpretation of results:

other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No. 1272/2008.

Reference 2

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study well documented, meets generally accepted scientific principles, acceptable for assessment Adopted according to OECD SIDS or other official EU regulation procedures (public available peer reviewed source).

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

yes

Remarks:

e.g. limited data on test substance available, only 3 instead of 4 animals per group

GLP compliance:

not specified

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

No. of animals per dose:

3

Parameter:

SI

Value:

0.73

Test group / Remarks:

Daily topical application of 25 µl of a 5% solution

Parameter:

SI

Value:

1.61

Test group / Remarks:

Daily topical application of 25 µl of a 10% solution

Parameter:

SI

Value:

1.13

Test group / Remarks:

Daily topical application of 25 µl of a 25% solution

Parameter:

SI

Value:

1.58

Test group / Remarks:

Intradermal injection of 50 µl of a 0.05% solution in  saline; after 5 days daily topical application of 25 µl of a 5 % solution

Parameter:

SI

Value:

1.93

Test group / Remarks:

Intradermal injection of 50 µl of a 0.5% solution in  saline; after 5 days daily topical application of 25 µl of a 5 % solution

Parameter:

SI

Value:

1.48

Test group / Remarks:

Intradermal injection of 50 µl of a 5% solution in  saline; after 5 days daily topical application of 25 µl of a 5 % solution

Stimulation indices: a.) 0.73, 1.61 and 1.13; b.) 1.58, 1.93 or 1.48

Interpretation of results:

other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No 1272/2008

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

There are no data on skin sensitisation available for Sulfuric acids, C9-11-iso-C10 rich, alkyl esters, sodium salt. Therefore, this endpoint is covered by read across to structurally related alkyl sulfates (AS) in accordance with Regulation (EC) No 1907/2006 Annex XI 1.5 “Grouping of substances and read-across approach”. In Annex XI 1.5 it is given that a read-across approach is possible for substances whose physico-chemical, 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 read-across approach show structural similarity. The most important common structural feature of the source and target substances 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 source and target substances in turn represent the predominant attribute in mediating effects on mammalian health. Therefore, the AS have similar physico-chemical, environmental and toxicological properties. 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.

Skin sensitisation

There is one study regarding skin sensitisation with Sodium octyl sulfate (C8 AS Na, CAS 142-31-4) and a second study with Sodium dodecyl sulfate (C12 AS Na, CAS 151-21-3) available. Both studies are accounted for in a Weight-of-Evidence (WoE) approach.

The first study assessed the skin sensitizing potential of C8 AS Na (CAS 142-31-4, analytical purity 32%) in a Local Lymph Node Assay similar to OECD Guideline 429 (P&G, 1992). In this study 12.5 µL of a 10, 50 and 100% aqueous solution of the test substance were topically applied on 4 consecutive days to 5 female CBA mice per dose group. 21 h after the last treatment all animals received injections with radiolabelled thymidine. Animals were sacrificed 5 h thereafter and auricular lymph nodes were removed. Single cell suspensions were prepared, washed and precipitated. The total radio counts in these precipitates were subsequently quantified by liquid scintillation spectrometry. The stimulation index in the carrier control was 1. The stimulation indices for the naive control and animals tretated with 10, 50 and 100% of the test substance were 2.4, 1.25, 2.7 and 3.1, respectively. The treatment had no significant effect on thymidine incorporation and thus the test substance showed not sensitising potential.

In the second study, the skin sensitizing potential of C12 AS Na (CAS 151-21-3) was assessed in a Local Lymph Node Assay similar to OECD guideline 429 (Ikarashi, 1993) on 3 mice per dose and experiment. BALB/c mice were treated daily via topical application (25 µL) of 5, 10 and 25% aqueous solution of the test item on 3 consecutive days. The stimulation index determined did not exceed the threshold value of 3.0. Hence, no skin sensitisation potential was identified for the test substance.

Based on the above mentioned results, the data of the read-across substances indicate no skin sensitisation potential. Therefore, Sulfuric acids, C9-11-iso-C10 rich, alkyl esters, sodium salt is also not expected to be a skin sensitiser. Moreover, sodium lauryl sulphate (C12 AS 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). Hence, there is a lot of experience with sodium lauryl sulfate in sensitising studies and no evidence occurred that it shows sensitising properties. Thus, skin sensitisation by members of the alkyl sulfates (AS) read-across approach is considered to be very 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

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) No. 1272/2008 (CLP) and are therefore conclusive but not sufficient for classification. No data available for respiratory sensitisation.