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:

Unfortunately no data is available regarding skin sensitization of 1,3-dioxepane. But data for other cyclic acetals consistently show that no indication for a skin sensitizing potential exists.

1,3,5-trioxane (CasNo. 110-88-3) proofed not to be sensitizing in a guinea pig maximization test (BASF AG, 1989). The study was performed according to the OECD guideline 406 and GLP.

In a supporting guinea pig study 1,3,5-trioxane was tested together with 1,3-dioxolane (CasNo. 646-06-0) and the cyclic tetramer of ethylene oxide (2,4,6,8-Tetraoxanonane, CasNo. 13353-03-2) (Rao, 1981). The assay was performed according to a guinea pig maximization assay (4 inductions, 1 indradermal application of adjuvance, 1 challenge), though reporting of the test results is not very detailed. For all 3 tested acetals no indication for a skin sensitizing potential was identified.

For 1,3-dioxolane additional data of low/undefined quality exists (not included in IUCLID/CSR). In a modified guinea pig assay according to Magnusson and Kligman no dermatitis related to oversensitivity was identified (Czajkowska et al. (1987), Experimental studies of toxic effects of 1,3,5-trioxane and 1,3-dioxolane. I Acute toxic effect. Medycyna Pracy 38: 184-190).

The data-base for evaluation can even be extended to 1,4-dioxane (CasNo. 123-91-1), a cyclic 6-ring with 2 oxygen atoms. Likewise no indication for a skin sensitizing potential was identified in a OECD guideline 406 maximization assay in guinea pigs (BASF AG, 1993; data not shown).

Summarized, a reliable cross reading to a variety of cylic acetalic and non acetalic molecules with 2-4 ring-oxygen atoms can be performed. All sensitization data unambigously shows that no concern for a skin sensitizing potential can be derived for 1,3-dioxepane. By weight of evidence and with respect of animal welfare the performance of an in vivo skin sensitization assay is not indicated.

Nevertheless, similar to 1,3,5-trioxane, 1,3-dioxepane degradation can result in the release of small amounts of formaldehyde (BASF AG, 1998), though to a way smaller extend. In order to protect formaldehyde-susceptible individuals, this observation should be indicated in the hazard communication (MSDS).


Migrated from Short description of key information:
A reliable cross-reading to other cyclic acetals consistently indicates no senitizing potential.

Respiratory sensitisation

Endpoint conclusion
Additional information:
Migrated from Short description of key information:
No data available

Justification for classification or non-classification

In a variety of structurally similar substances no indications for a skin sensitizing potential were identified. Therefore no classification for skin-sensitization is warranted.