Registration Dossier

Administrative data

Link to relevant study record(s)

Description of key information

No experimental data on toxicokinetics, metabolism and distribution of the submission substance are available. Based on the physicochemical properties of the submission substance it is anticipated that the substance is bioavailable via the oral, dermal or inhalation route. Beta oxidation or direct hydrolysis are thought to be reasonable metabolism pathways leading to systemic exposure to 3,5,5-trimethylhexanoic acid. Given the results from repeated dose experiments no concern for bioaccumulation is raised.

Key value for chemical safety assessment

Additional information

The submission substance is expected to be bioavailable for oral/dermal/inhalation routes based on the given molecular size (MW of 271.4 g/mol) and the octanol water partition coefficient (LogPow 2.47). No metabolism or kinetic study is available on the submission substance. Based on the structural analysis and the indication obtained in the microbial degradation study (metabolite identification in samples of Zahn-Wellens Test), two degradation pathways can be reasonably derived:

-      Beta oxidation at the terminal carboxylic acid moiety in combination with hydrolysis at amide bond

-      Direct hydrolysis at the amide moiety

Both pathways are leading to systemic exposure to 3,5,5-trimethylhexanoic acid, which serves as surrogates of the proposed read-across approach. The bioaccumulating potential is estimated to be of no concern, because clear recovery effects were observed in the provided 28 -day toxicity studies.