Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

In a modified local lymph node assay (LLNA; De Jong et al., 2002) conducted similar to the OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay; particular exception: the animals were treated only 3 times) used to determine the sensitising activity of four chemicals used for the production of natural rubber latex products, the test substance was epicutaneously administered on the ear of BALB/c mice (4) and the proliferating activity in the draining (auricular) lymph node (LN) was determined by ex vivo [3H]-thymidine incorporation.

[3H]-TdR incorporation in DNA per lymph node expressed as count per min was increased dose-dependently from 599±264 at 0.1% dose level to 2035±534 at 30%. Accordingly, the stimulation index also increased dose-dependently and was >3 (3.7; positive sensitizer) at concentration level of 20% (1.1 at 0.1 and 1.0%, 1.4 at 5.0%, 2.5 at 10% and 2.9 at 30%) in the first experiment. However, when the test substance was reevaluated 3 times at 20% (the concentration with SI>3 in the first experiment) for consistency/reproducibility, the resulting SIs were 2.7, 1.2 and 1.7 respectively (<3; negative sensitizer).

Pretreatment with 1-10% SDS 1 h before application of the test substance enhanced the responses consistently (proliferation per LN / corresponding SIs: 2451±1691 /3.7 and 13469±10906 /20.1, respectively for SDS 1% + test substance and SDS 10% + test substance), identifying the test substance as sensitizers. SDS was tested sensitizing (proliferation per LN / corresponding SIs: 892±144 /0.8, 2880±1460 /2.5 and 3780±1770 /3.3, respectively for 1%, 3% and 10% SDS concentration level), indicating that SDS had synergistic activity on the LN responses of the administered test substance in the LLNA. IFN-γ and IL-4 cytokine production was also only observed after pretreatment of the animals with 10% SDS.

Based on the results of the present study, inconsistent results were obtained for the test substance in the LLNA.

The test substance was also evaluated for dermal sensitization in 20 female CF-1 mice by mouse ear swelling test (MEST; Virginia Chemicals1, 1987). Following induction, the challenge was administered by topical application of 50% solution on day 10. A rechallenge was performed 7 days later with a topical application of 50% solution. Challenge and rechallenge elicited no response in either test or irritation control groups at 24 or 48-hour evaluations. 80% and 100% positive response in the DCNB-inducted and challenged groups at 24-hour and 48-hour evaluations, respectively, confirmed the validity of the test system (Virinia Chemicals, reliablity score: 2).

Migrated from Short description of key information:
Skin sensitisation: not sensitizing.
Respiratory sensitisation: no data available.

Respiratory sensitisation

Endpoint conclusion
Additional information:
Migrated from Short description of key information:
No data available for the determination of the respiratory sensitisation potential.

Justification for classification or non-classification

No need for classification according to Annex VI of Directive 67/548/EEC and according to the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.