RIFM fragrance ingredient safety assessment, tetrahydro-6-(3-pentenyl)-2H-pyran-2-one, CAS Registry Number 32764-98-0.

The existing information supports the use of this material as described in this safety assessment. Tetrahydro-6-(3-pentenyl)-2H-pyran-2-one was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data show that tetrahydro-6-(3-pentenyl)-2H-pyran-2-one is not genotoxic. The repeated dose, reproductive, and local respiratory toxicity endpoints were evaluated using the Threshold of Toxicological Concern (TTC) for a Cramer Class II material, and the exposure to tetrahydro-6-(3-pentenyl)-2H-pyran-2-one is below the TTC (0.009 mg/kg/day, 0.009 mg/kg/day, and 0.47 mg/day, respectively). Data and read-across to 5-hydroxy-7-decenoic acid δ-lactone (CAS # 25,524-95-2) show that there are no safety concerns for tetrahydro-6-(3-pentenyl)-2H-pyran-2-one for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on data and ultraviolet/visible (UV/Vis) spectra; tetrahydro-6-(3-pentenyl)-2H-pyran-2-one is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; tetrahydro-6-(3-pentenyl)-2H-pyran-2-one 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.