RIFM fragrance ingredient safety assessment, hexadeca-1,5-lactone, CAS Registry Number 7370-44-7

The existing information supports the use of this material as described in this safety assessment. Hexadeca-1,5-lactone was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from the target material and read-across analog hydroxynonanoic acid, δ-lactone (CAS # 3301-94-8) show that hexadeca-1,5-lactone is not expected to be genotoxic. Data from analog δ-decalactone (CAS # 705-86-2) provide a calculated Margin of Exposure (MOE) > 100 for the repeated dose and reproductive toxicity endpoints. Data from analog δ-octalactone (CAS # 698-76-0) show that there are no safety concerns for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on ultraviolet (UV) spectra; hexadeca-1,5-lactone is not expected to be phototoxic/photoallergenic. The local respiratory toxicity endpoint was evaluated using the Threshold of Toxicological Concern (TTC) for a Cramer Class I material; exposure is below the TTC (1.4 mg/day). For the hazard assessment based on the screening data, hexadeca-1,5-lactone is not Persistent, Bioaccumulative, and Toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards. Hexadeca-1,5-lactone could not be risk screened as there were no reported volumes of use for either North America or Europe in the 2015 IFRA Survey.