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:

Human patch testing

Various human patch studies were available for the registered substance, however quality was different between studies.

- In a key skin sensitisation study a 15 mm patch of the test item containing 35.8% active ingredient (2.5% in petrolatum) was applied to patch sites on the backs or volar forearms of 100 subjects for ten alternate-day 24 hour periods under occlusion (Kligman, 1977). Following a seven-day rest period, 15mm challenge patches of the test item (1% in petrolatum) were applied in the same manner to fresh sites on the backs or volar forearms of all 100 subjects for 24 hours. Challenge sites were read on removal of the patch and 24 hours thereafter, using the 0-4 scale. There were no instances of irritation or sensitisation from this material on the Draize-Shelanski Patch Test. It is unlikely that this test item would present a danger of irritation or sensitisation in normal, intended use.

- In a supporting skin sensitisation study, 100 adult males received 3 successive applications of test item containing 35.8% active ingredient over cantharidin-induced blisters under strict occlusion by aluminum foil and adhesive tape, for 5 days (Kligman 1956). Three weeks after the end of the test, each of the individuals was challenged with a 48 hour patch test to the 35% concentration, showing no sensitisations in this group of 100 men, despite the vigourous conditions of exposure.

- In two disregarded human patch test studies (Hollander, 1943; Hollander, 1956) subjects were tested with 1, 2, 3 and 5% test item containing 35.8% active ingredient versus control materials. Data on study design were missing, and results were ambiguous, therefore they were not further taken into account.

- In conclusion, it is unlikely that this material would present irritation or sensitisation in normal, intended use.

Conclusion

- Based on the repeated negative findings in the human patch studies, potential for skin sensitisation can be excluded.

- Further information supporting the absence of sensitisation potential is also provided in the read across justification for the N2 group, showing that results of the guineapig maximisation test in the group were also negative (justification with data matrix separately attached in Section 13).


Migrated from Short description of key information:
Two human patch studies with test item containing 35.8% active ingredient were taken into account for evaluation of sensitisation; both demonstrating that sensitisation is unlikely.

Justification for selection of skin sensitisation endpoint:
Key study

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

Based on these results and according to the EC criteria for classification and labelling requirements for dangerous substances and preparations (Guidelines in Commission Directive 93/21/EEC) and CLP regulation (EC No. 1272/2008 of 16 December 2008) the test substance does not have to be classified and has no obligatory labelling requirement for sensitisation.