Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

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

1,5-Naphthylene diisocyanate (NDI) was investigated in the modified local lymph node assay (LLNA-IMDS) on female mice according to OECD TG 429 (Vohr, 2006). Concentrations of 0 (vehicle control), 2, 10 and 50% formulated in acetone/olive oil (4:1) were tested. The results show that NDI has a sensitizing potential in mice after dermal application. Compared to vehicle treated animals there was a significant increase regarding the weights of the draining lymph nodes and the cell counts in all dose groups. The corresponding cell count indices were 4.06, 4.15 and 4.42 exceeding the "positive level" of index 1.4. A significant increase compared to vehicle treated animals regarding ear swelling and ear weights was detected in all dose groups. An increase in this parameter points to an acute irritant (inflammatory) response. However, such an irritant property in this case is also combined with a strong skin sensitizing potential of a test compound.

Respiratory sensitisation

Endpoint conclusion
Additional information:

This information is not available.

Justification for classification or non-classification

Skin sensitisation

Not classified under Annex I of Directive 67/548/EEC or Annex VI-1 of Regulation (EC) No 1272/2008. Differing from this a skin sensitising potential in mice detected in a modified LLNA leads to the following classification according to Annex I of Regulation (EC) No 1272/2008: Category 1 (H317: May cause an allergic skin reaction). Since the LLNA is over-predictive for the endpoint skin sensitisation with diisocyanates and no further animal data or human data on skin sensitisation are available for NDI, a reliable assessment of the sensitisation potency is not possible. Therefore, according to Regulation (EU) No 286/2011 (3.4.2.2.1.1: Skin sensitisers shall be classified in Category 1 where data are not sufficient for sub-categorisation) NDI should be currently classified in Category 1, without further sub-categorisation.

Respiratory sensitisation

Classified under Annex I of Directive 67/548/EEC with R42 (may cause sensitisation by inhalation). This classification corresponds to

Category 1 (H334: May cause allergy or asthma symptoms or breathing difficulties if inhaled) according to Annex VI-1 of Regulation (EC) No 1272/2008. Since no animal data and no conclusive human data on respiratory sensitisation are available for NDI, a reliable assessment of the sensitisation potency is not possible. Therefore, according to Regulation (EU) No 286/2011 (3.4.2.1.1.1: Respiratory sensitisers shall be classified in Category 1 where data are not sufficient for sub-categorisation) NDI should be currently remain in Category 1, without further sub-categorisation.