Registration Dossier

Administrative data

Description of key information

Dermal and ocular irritation studies have been conducted on three substances in the TDI-I category. In vivo studies on dermal and ocular irritation have been conducted on Diurea 8 (Sanders 2011a and 2011c, respectively) and Tetraurea 2 (Sanders, 2011b and 2011d, respecitvely), and in vitro studies on dermal and occular irritation have been conducted on the rection product of m-tolylidene diisocyanate, cyclohexamine, cyclohex-1,2 -ylenediamine and (Z)-octadec-9 -enylamine (Richeux 2010 and 2009, respecitvely). No classifiable irritant responses were observed in any of the studies when applied to skin. For potential eye irritancy, Diurea 8 and Tetraurea 2 were classified as a mild irritant according to a modified Kay and Calandra classification system but remained unclassified according to the Classification, Labelling and Packaging Regulation or the Globally Harmonised Classification System. For the reaction product of m-tolylidene diisocyanate, cyclohexamine, cyclohex-1,2 -ylenediamine and (Z)-octadec-9 -enylamine no eye irritation was observed.

No data were identified relating to irritation of the respiratory tract. Given the results from the skin and eye irritation studies it is unlikely that TDI-category 1 members would cause significant respiratory irritation.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Additional information

PU TDI-1 substances all contain the same core structure, with predominantly linear alkyl chains (C8 – C18) attached. The same substance can contain structures with different alkyl chain lengths, and some substances may contain small amounts of structures with cyclic groups. PU TDI-1 structures are therefore similar between all category members, and organisms will be exposed to very similar compounds. Organisms would be exposed to common structures, only differing by the length of the alkyl chain or whether cyclic groups are present. In the body, there may be metabolism of the PU TDI-1 structures, however due to the structural similarity of the parent compounds any metabolites are also likely to be similar. 

Justification for classification or non-classification

The category members are not classified as irritant to skin as the in vivo rabbit studies and in vitro human skin model study were negative (Sanders 2011a, Sanders 2011b, Richeaux 2010). The substances are also not classified as an irritant to the eye since the modified Kay and Calandra score for eye irritancy in the rabbit in vivo eye irritation studu did not meet the criteria for classification according to the Classification, Labelling and Packaging Regulation or the Globally Harmonised Classification System (Sanders 2011c, Sanders 2011d), and the in vitro BCOP study reported that the test item should not be classified (Richeux 2009).