Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (sensitising)
Additional information:

Short description of key information:
1,4-Benzenediamine, N,N'-mixed Ph and tolyl derivs. was subjected to a guinea pig maximisation test (GPMT) according to OECD and GLP guidelines. The induction phase included both intradermal and epidermal exposures to test chemical plus adjuvant. Two epicutaneous challenges were performed at Day 21 and Day 28. Dermal edema, desquamation and blanching were observed in a high proportion of test animals. The results show that the test substance has sensitisation activity.

Discussion

The key study was performed according to the Guinea-pig maximisation test as described in OECD test guideline 406, consisting of an intradermal and epidermal induction, and two epicutaneous challenges at day 21 and day 28.

The dermal response following 48h after the first challenge to 25% or 100% of chemical resulted in clinical effects (edema or desquamation) for 15% or 25% of test animals, respectively.

48 Hours after the second challenge 55% of the animals exposed to 25% of test chemical showed signs of desquamation, edema or blanching. In the test group exposed to 100% of test chemical, 75% of the animals showed signs of a sensitization reaction after 48 hours.


Justification for classification or non-classification

1,4-Benzenediamine, N,N'-mixed Ph and tolyl derivs. was subjected to a guinea pig maximisation test (GPMT) according to OECD and GLP guidelines. The induction phase included both intradermal and epidermal exposure to solutions of 5% test substance in acetone/propylene glycol.

The test animals did show clinical skin effects (dermal edema, desquamation, blanching) aftert both the Day 21 challenge and the Day 28 rechallenge trial. Individual responses were not strong, but up to 75% of the test animals did show signs of one or more of these skin responses. As a consequence, 1,4-benzenediamine, N,N'-mixed Ph and tolyl derivs. is to be classified as skin sensitiser Category 1B according to CLP Regulation (EC) No. 1272/2008 (amended according to Commission Regulation No 286/2011). Upon application of the potency criteria it can be concluded that the test substance shows moderate sensitisation.

When comparing the observed effects with the criteria specified in Directive 67/548/EEC (Dangerous Substances Directive), it can be concluded that the second criterion (positive result of at least 30% of the animals from an appropriate animal test) is fulfilled. As a consequence, 1,4-benzenediamine, N,N'-mixed Ph and tolyl derivs. is to be classified as a skin sensitiser according to Directive 67/548/EEC (Dangerous Substances Directive).