Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

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

ZAN 573 is sensitising in the LLNA at concentrations of 50%, 25% and 10% in DMF. The EC3 is 2.1%, a "moderate" sensitiser (where the concentration resulting in an EC3 is ≥1% and < 10%, according to ECETOC Technical Report No. 87, 2003).

As ZAN 573 is a UVCB, there is insufficient data to determine the species which is responsible for the sensitisation. The sensitiser trimellitic anhydride is present as a residual.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available
Additional information:

Respiratory sensitisation is demonstrated and discussed in the repeated dose inhalation test results for trimellitic anhydride (Leach, Hatoum and Derrick, 1988). Category members trimellitic anhydride and phthalic anhydride have been reported to be respiratory sensitisers in occupational settings. Additionally, the commercial product contains trimellitic anhydride at levels requiring classification for sensitisation.

The observation of dermal sensitisation is consistent with the behavour of other members of the category of cyclic acid anhydrides. The category is based on the similar chemical behaviour and analogous breakdown products in environmental and biological systems. The common functional group is a 1,3-dioxo-1,3-dihydro-2-furan ring (i.e., a cyclic acid anhydride) directly attached to an aromatic ring. The cyclic anhydride moiety is quickly hydrolysed to form a dioic acid. The cyclic acid anhydride moiety and its dioic acid derivatives are the principal loci of toxicity, rather than the remainder of the molecule.Within the category, oligomeric forms of the cyclic acid anhydrides are less likely to be absorbed across biological membranes than the simple, monomeric forms, so that this read-across represents the worst case scenario. The read-across information to acceptable to fulfil the information requirements of the REACH Annexes VII-X, to be the basis for classification and labelling decisions, and for risk assessment.

Justification for classification or non-classification

The substance is classified as a dermal sensitiser, Category 1, and a respiratory sensitiser, Category 1, based on test results, similar behaviour of category members and content of residual trimellitic anhydride in the commercial product.