Update to RIFM fragrance ingredient safety assessment, γ-hexalactone, CAS Registry Number 695-06-7

Abstract

γ-Hexalactone was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, photoirritation/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog γ-valerolactone (CAS # 108-29-2) show that γ-hexalactone is not expected to be genotoxic. Data on γ-hexalactone provide a calculated Margin of Exposure (MOE) > 100 for the repeated dose toxicity and developmental toxicity endpoints. Data on read-across analog γ-dodecalactone (CAS # 2305-05-7) provide a calculated MOE >100 for the fertility endpoint. Data from read-across analog 4-hydroxybutanoic acid lactone (CAS # 96-48-0) show that there are no safety concerns for γ-hexalactone for skin sensitization under the current declared levels of use. The photoirritation/photoallergenicity endpoints were evaluated based on ultraviolet/visible (UV/Vis) spectra; γ-hexalactone is not expected to be photoirritating/photoallergenic. The local respiratory toxicity endpoint was evaluated using the Threshold of Toxicological Concern (TTC) for a Cramer Class I material, and the exposure to γ-hexalactone is below the TTC (1.4 mg/day). The environmental endpoints were evaluated; γ-hexalactone 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 (VoU) in Europe and North America (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1.