Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

The dermal sensitizing potential of the test article, FC-770, was evaluated in a local lymph node assay (LLNA) in female CBA/J mice following OECD Guideline 429 (effective April 2002). This concentration did not cause irritation in a preliminary irritation screen. In the definitive study, animals (5/group) were administered 25 µL of control (Milli-Q or Milli-U water) or 100% of the test article by topical application to the dorsum of each ear once daily for three consecutive days. Clinical observations were recorded daily. Body weights were recorded on days 1 and 6. Ear swelling measurements were recorded on days 1, 3 and 6. On day 6, the number of proliferating lymph node cells in the auricular lymph nodes were determined using a 3H-methyl thymidine method. The Stimulation Index (SI) was calculated and substances with a SI > 3 are considered to be potential sensitizers. To achieve more information regarding the SI value, the study was repeated with two additional groups. No skin reactions were observed in any animals. The calculated median SI was 2.8 and there was no indication that the test substance could elicit an SI = 3 when tested up to 100%. The positive control (hexylcinnamaldehyde) is tested once every 6 months at NOTOX and the most recent test indicated that the test method was valid. Based on the results of this study, the test article is not a dermal sensitizer at concentrations up to 100%.


Because these substances exhibit similarity in their physicochemical properties and toxicological properties in mammals, and because available data indicates that parent molecules are not reactive toward biological molecules and cannot undergo bioactivation by normal enzymatic processes, they can be considered members of a chemical category. Data gaps for partitioning properties, mammalian and ecological toxicity can therefore be addressed by read-across and/or trend analysis between category members. All members of the category are non-sensitizing in dermal sensitization studies.

Migrated from Short description of key information:
Perfluorohexane is a member of the Fluorochemical Inerts category. A Murine Local Lymph Node Assay was conducted on one category member: FC-770. The results indicate that FC-770 is not a skin sensitizer. Classification for category members is based on experimental results for certain members of the class. Since one of the defining characteristics of the class is a lack of biological effects based on chemical and electronic properties, the results from tests (mammalian toxicity, environmental and ecotoxicity) are applicable to all members of the category.

Justification for classification or non-classification

The read across data do not meet the criteria for classification as a skin sensitizer.