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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:

A study was conducted to determine the in vivo skin sensitisation potential of the read across substance L-glutamic acid, N-coco acyl derivs., monosodium salts according to OECD Guideline 406, in compliance with GLP. The experiment was performed on male Guinea pigs. For the induction phase, the undiluted test substance was used. During challenge, 12 out of 20 animals reacted with distinct erythema. Therefore, a purified/diluted sample (25%) was prepared for the re-challenge procedure. During the re-challenge with the purified sample, no skin reactions were observed after 24 and 48 h in any animal. Under the study conditions, the substance was not sensitizing to guinea pig skin (RCC Ltd, 2001).

The skin sensitisation potential of the test material was also determined in a GLP study conducted in accordance with the standardised guidelines OECD 429 and EU Method B. 42, using the local lymph node assay method. In the definitive, test animals were administered the test material at 25, 10 and 5 (w/v) %, formulated in 1 % Pluronic aqueous solution. The dosing range and vehicle were selected based on the results of two preliminary studies, a compound solubility test and a preliminary irritation/toxicity test. Negative vehicle and positive controls (97.8 % hexyl cinnamic aldehyde) were run concurrently for comparison. Four female CBA/J Rj mice per dose were topically administered 25 µL of the appropriate test material formulation on the dorsal surface of each ear for three consecutive days (days 1, 2 and 3). There was no treatment on Days 4, 5 and 6. On Day 6, the cell proliferation in the local lymph nodes was measured by incorporation of tritiated methyl thymidine (³HTdR) and the values obtained were used to calculate stimulation indices (SI). Under the conditions of the test, no mortality, systemic clinical signs, treatment related effects on body weights, or indications of any irritancy at the site of application were observed in any of the treatment groups. Test material precipitate was observed in the 25 (w/v) % dose group on Days 1-5 and in the 10 and 5 (w/v) % dose groups on Days 2-3. The observed stimulation index values were 1.6, 0.8 and 0.9 at concentrations of 25, 10 and 5 (w/v) %, respectively. Since the measured indices were less than 3, the test material is considered to be a non-sensitizer. As potassium salts are uually more toxic that sodium one, Read Across is fully justified.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

Based on an in vivo skin sensitisation study with the read-across substance L-glutamic acid, N-coco acyl derivs., monosodium salts and on an in-vivo LLNA study made on same molecule neutralized with Potassium,  no classification for skin sensitisation is warranted according to EU CLP (1272/2008) criteria.