Registration Dossier

Administrative data

Description of key information

Irritation / corrosion:
- skin: not irritating (OECD 404, human data);
- eye: not irritating (OECD 405);

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

Skin

Skin irritation by palmitic acid was evaluated in a study performed under GLP according to OECD guideline 404 with the exception, that the test was performed under occlusive condition (Kästner, 1988). Four Kleinrussen rabbits received an application of 0.5 g palmitic acid to the shaved skin under occlusion for 4 hours. The readings 24, 48, and 72 hours after application did not reveal any signs of irritation, thus resulting in mean scores of 0 for erythema and edema, respectively. As a consequence, test was cancelled due to welfare reasons. Based on the results, palmitic acid can be regarded as not irritating to skin.

In a study with human subjects, palmitic acid and 19 other substances were investigated with a closed epicutanous test. 10 µl of palmitic acid at a concentration of 50% was applied to the back of the volunteers for 24 hours using a Large Finn Chamber (Matthies, 1988). The reactions were scored for edema, erythema, scaling and fissures 1, 6, 24, 48, 72 and 144 hours after application. As result, for all readings the score 0 was found.

 

Eye

Eye irritation by palmitic acid was analyzed in a study performed in accordance with GLP and according to OECD guideline 405 (Kästner, 1988). 0.1 g of palmitic was instilled into the rtights eyes of four Kleinrussen rabbits while the untreated left eyes served as control. The reactions were examined 1, 6, 24, 48, and 72 hour after administration and resulted in mean scores of 0, 0, 0.3, 0 and 0 for corneal opacity, iris, conjunctival redness and chemosis, and exudation, respectively. Since all signs were subsided on day three after instillation, the study was cancelled on that day due to animal welfare reasons. Based on the findings, palmitic acid can be regarded as not irritating to eyes.

Palmitic acid was also not found to be irritating to eyes in the study performed according to national guidelines since no signs of irritation were noted (Briggs, 1976).

Justification for classification or non-classification

The substance may contain few of lauric acid (C12), which is classified as R41/eye damage Cat 1. The specific concentration limit for the lauric acid is established as 73.6% based on a reliable experimental data. According to DPD (1999/45/EC) or CLP (1272/2008/EC) classification criteria for irritation/corrosion, palmitic acid dose not fulfill the criteria for classification and thus a non-classification is warranted for this endpoint, as the concentration of C12 is lower than 73.6%.