RIFM fragrance ingredient safety assessment, octyl isobutyrate, CAS Registry Number 109-15-9

Abstract

The existing information supports the use of this material as described in this safety assessment. Octyl isobutyrate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog hexyl isobutyrate (CAS # 2349-07-7) show that octyl isobutyrate is not expected to be genotoxic. Data on analog propyl (2S)-2-(1,1-dimethylpropoxy)-propanoate (CAS # 319002-92-1) provide a calculated Margin of Exposure (MOE) > 100 for the repeated dose and reproductive toxicity endpoints. Data from analog hexyl 2-methylbutyrate (CAS # 10032-15-2) provided octyl isobutyrate a No Expected Sensitization Induction Level (NESIL) of 7000 μg/cm2 for the skin sensitization endpoint. Octyl isobutyrate is not expected to be phototoxic/photoallergenic based on ultraviolet/visible (UV/Vis) spectra. The local respiratory toxicity endpoint was evaluated using the Threshold of Toxicological Concern (TTC) for a Cramer Class I material; exposure to is below the TTC (1.4 mg/day). The environmental endpoints were evaluated; octyl isobutyrate was found not to be Persistent, Bioaccumulative, and Toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.