Registration Dossier

Administrative data

Description of key information

Although no conclusions can be drawn regarding the irritant properties of naphthalene from studies in humans, data from animal studies indicate that it is only a slight skin and eye irritant insufficient to warrant classification. As for respiratory irritation, nasal effects found in rodents  are not considered as representative of humans (see IUCLID 7.5).

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)

Respiratory irritation

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

Additional information

After occlusive dermal administration of 0.5 g naphthalene on the clipped skin of six rabbit for 24 h, slight erythema and edema were observed (scores 2 or lower). Observation times were immediately and 48 h after removal of the patch. At the 48 h reading, skin reactions were diminished to some extent but had not completely subsided. Due to the moderate scores observed, it is concluded that irritation effects will have disappeared at the end of the regular 2 weeks observation period. Criteria for classification as irritating according to EU regulations have not been exceeded.

Eye reactions were minor and could only be noted at day 1 and 2 of the observation period (iris reaction, conjunctival redness, and chemosis, score 1 or 2). Effects had disappeared at day 3. Cut-off scores for classification as irritating to the eye according to EU regulations have not been exceeded.

Justification for classification or non-classification

Criteria for classification as irritating to the skin or eye according to EU regulations are not fulfilled. Therefore, no classification needed.