Update to RIFM fragrance ingredient safety assessment, 2,6-dimethylocta-2,4,6-triene, CAS Registry Number 673-84-7

2,6-Dimethylocta-2,4,6-triene was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, photoirritation/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog myrcene (CAS # 123-35-3) show that 2,6-dimethylocta-2,4,6-triene is not expected to be genotoxic. The repeated dose, reproductive, and local respiratory toxicity endpoints were evaluated using the Threshold of Toxicological Concern (TTC) for a Cramer Class I material, and the exposure to 2,6-dimethylocta-2,4,6-triene is below the TTC (0.03 mg/kg/day, 0.03 mg/kg/day, and 1.4 mg/day, respectively). Data from read-across analog myrcene (CAS # 123-35-3) show that there are no safety concerns for 2,6-dimethylocta-2,4,6-triene for skin sensitization under the current declared levels of use. The photoirritation/photoallergenicity endpoints were evaluated based on ultraviolet/visible (UV/Vis) spectra; 2,6-dimethylocta-2,4,6-triene is not expected to be photoirritating/photoallergenic. The environmental endpoints were evaluated; 2,6-dimethylocta-2,4,6-triene was found not to be Persistent, Bioaccumulative, and Toxic (PBT) as per the International Fragrance Association (IFRA) Environmental Standards, and its risk quotients (RQs), based on its current volume of use (VoU) in Europe (EU), North America (NA), Asia-Pacific (AP), and South America (SA) (i.e., Predicted Environmental Concentration/Predicted No Effect Concentration [PEC/PNEC]), are <1. 2,6-Dimethylocta-2,4,6-triene was not able to be risk screened for Japan (JP) as there was no reported VoU for this region in the 2023 IFRA Survey.