Aluminium trilactate

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

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

Adequacy of study:

key study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented publication which meets basic scientific principles; although pre-guideline study, equivalent to later adopted OECD guideline

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

no

GLP compliance:

not specified

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

other: CBA/Ca

Sex:

not specified

Details on test animals and environmental conditions:

TEST ANIMALS
- Age at study initiation: 7 to 12 weeks
- Weight at study initiation: no data
- Housing: no data
- Diet (e.g. ad libitum): no data
- Water (e.g. ad libitum): no data
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data

Vehicle:

other: Petrolatum

Concentration:

5.0, 10.0, 25.0%

No. of animals per dose:

4

Details on study design:

Mice were treated with 25 µL of test material, or with an equal volume of the vehicle alone, on the dorsum of both ears. Treatment was performed once daily for 3 consecutive days. Five days after the initiation of exposure, all mice were injected by the tail vein with 250 µL of phosphate buffered saline (PBS) containing 20 µCi of tritiated thymidine. Mice were killed 5 hours later and the draining lymph nodes excised and pooled for each experimental group. A single-cell suspension of lymph node cells was prepared by mechanical disaggregation. The lymph node cell suspension was washed twice in an excess of PBS and then precipitated with 5% trichloroacetic acid (TCA) at 4°C for 18 h. Pellets were resuspended in TCA and the incorporation of tritiated thyrnidine measured by P-scintillation counting. A substance was regarded as a skin sensitiser if, at any test concentration, the proliferation in treated lymph nodes was threefold or greater than that in the concurrent vehicle treated controls.

Parameter:

SI

Remarks on result:

other: 5.0%: 0.8 10.0%: 0.8 25.0%: 0.7

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: no data

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: other: CLP, EU GHS (Regulation (EC) No 1272/2008)

Conclusions:

Aluminium chloride hexahydrate is not sensitising in the LLNA.

Executive summary:

In a dermal sensitisation study equivalent to OECD guideline 429 with Aluminium chloride hexahydrate (99% a.i) in petrolatum, groups of 4 young adult CBA/Ca mice were tested using the LLNA method.

The test substance was applied in concentrations of 5.0, 10.0 and 25.0%. The resulting stimulating indices (SI) were 0.8, 0.8 and 0.7, respectively.  

In this study, Aluminium chloride hexahydrate is not a dermal sensitiser.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Animal or human data on skin sensitisation are not available for the substance Aluminium trilactate.

A read-across to the moieties of Aluminium trilactate - Lactic acid and Aluminium - is used for hazard assessment. This read-across approach is adequate as the salt like substance Aluminium trilactate will dissociate to Lactic acid and Aluminium ions.

Missing sensitising activity of Lactic acid can be taken for granted. Based on guinea pig test result (i.e. TG 406) and LLNA results, Lactic acid has been evaluated as non-sensitiser by the European Centre for the Validation of Alternative Methods (ECVAM) as well as the US Interagency Coordinating Committee on the Validation of Alternative Methods (ICCVAM) in the course of setting the Murine Local Lymph Node Assay (LLNA) Performance Standards and is now listed as negative reference substance in the OECD Guideline for Testing of Chemicals 429, Skin Sensitization: Local Lymph Node Assay, adopted 22 July 2010.

Based on reliable, adequate and relevant tests on soluble Aluminium compounds like Aluminium chloride, there are no indications on a sensitising activity of Aluminium.

In a dermal sensitisation study equivalent to OECD guideline 429 with Aluminium chloride hexahydrate (99% a.i) in petrolatum, groups of 4 young adult CBA/Ca mice were tested using the LLNA method.

The test substance was applied in concentrations of 5.0, 10.0 and 25.0%. The resulting stimulating indices (SI) were 0.8, 0.8 and 0.7, respectively. In this study, Aluminium chloride hexahydrate is not a dermal sensitiser.

This finding is further supported by a Mouse Ear Swelling Test which also identified Aluminium chloride as not sensitising.

In consideration of the missing sensitising activity of Lactic acid and Aluminium, Aluminium trilactate is not likely to be skin sensitising and does not need to be classified.

Migrated from Short description of key information:
No animal or human data on skin sensitisation are available for the substance Aluminium trilactate.
Lactic acid has been evaluated as non-sensitiser and is now listed as negative reference substance in the OECD Guideline for Testing of Chemicals 429, Skin Sensitization: Local Lymph Node Assay (LLNA), adopted 22 July 2010. Aluminium (as Aluminium chloride) was found to be not sensitising in a LLNA as well as in a Mouse Ear Swelling Test (MEST).
In consideration the missing sensitising activity of Lactic acid and Aluminium, Aluminium trilactate is not likely to be skin sensitising.

Justification for selection of skin sensitisation endpoint:
The key study is of high quality (Klimisch score=2); the Local Lymph Node Assay is the preferred assay for this endpoint.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information:

Experimental data on respiratory sensitisation are not available. However, Aluminium trilactate has a very low vapour pressure (melting point > 300°C), so the potential for the generation of inhalable forms is low. Also the use of this substance will not result in aerosols, particles or droplets of an inhalable size, so exposure to humans via the inhalatory route will be unlikely to occur. Taking further into account the absense of skin sensitisation potential of Lactic acid and Aluminium, respiratory sensitisation is not expected to be of concern for Aluminium trilactate.

Migrated from Short description of key information:
Experimental data on respiratory sensitisation are not available. However, considering the absense of skin sensitisation potential of Lactic acid and Aluminium, respiratory sensitisation is not expected to be of concern for Aluminium trilactate.

Justification for classification or non-classification

From reliable, adequate and relevant read-across data there is no indication on an intrinsic sensitising activity of Aluminium trilactate, thus the classification criteria regarding sensitisation outlined in regulation (EC) 1272/2008 or the former European directive on classification and labelling 67/548/EEC are not met.