Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Additional information

All relevant and available information on intrinsic properties of MWCNT are cited in chapter 7 of the IUCLID. Although a large number of studies on the toxicity of MWCNTs have recently been published, clear characterization of the test materials including sample preparation which are quite essential for ensuring reproducibility and reliability in the toxicity test using suspension, in vivo and in vitro methods, is often missing. Importantly, modifications of some specific characteristics of the MWCNT tested such as variations in particle size distribution or length might give rise to differences in the toxicological profile. 

Toxic effects of different MWCNTs seem to depend on the form (length) and physico-chemical properties (metal content, aggregation/agglomeration, surface chemistry, and functionalisation). Thus for the time being, a case-by-case approach would be appropriate and the hazard assessment for MWCNT meeting the form described in section 4.5 of the IUCLID dossier is based solely on the information collected with this MWCNT. That is the reason why a comprehensive documentation in the IUCLID dossier and the chemical safety report involved automatically is restricted to all available and relevant data on the MWCNT meeting the form described in section 4.5 of the IUCLID dossier. That means on the other hand that the values used for the risk assessment exercise should not be used in general for all MWCNTs or CNTs, as the results obtained with one particular type of MWCNTs may not necessarily be relevant for other CNTs with other dimensions and properties

In addition the information on MWCNT not meeting the form described in section 4.5 of the IUCLID dossier (the differences can be tracked back to the original papers or because in others the characterization of the materials was unclear or inclomplete) is also included in the IUCLID dossier but the entries are restricted to the information on data source to give a quick overview of all available data.

Skin irritation:

The test material meeting the form described in section 4.5 of the IUCLID dossier is not irritating to the skin of rabbits (OECD TG 404) (Gmelin, 2006a). No systemic intolerance reactions were observed.

Eye irritation:

The test material meeting the form described in section 4.5 of the IUCLID dossier shows slight irritation on rabbit eyes in a study performed according to OECD TG 405 (Gmelin, 2006b). The ocular reactions were restricted to the conjunctivae (predominately redness) and were reversible within 72 hours at the latest. Systemic effects were not observed.

Justification for classification or non-classification

Skin irritation:

No classification required according to EU-Directive 67/548/EEC, Annex VI.

No classification required according to Regulation (EC) No 1272/2008, Annex I.

Eye irritation:

No classification requiredaccording to EU-Directive 67/548/EEC, Annex VI.

No classification required according to Regulation (EC) No 1272/2008, Annex I.