RIFM fragrance ingredient safety assessment, 2-acetylthiazole, CAS Registry Number 24295-03-2

Area of Science:

• Chemical safety assessment
• Toxicology
• Environmental risk evaluation

Background:

• 2-Acetylthiazole is a widely used fragrance ingredient.
• Comprehensive safety data is essential for regulatory compliance and consumer safety.
• Previous assessments may not have covered all relevant toxicological and environmental endpoints.

Purpose of the Study:

• To evaluate the safety of 2-acetylthiazole across multiple toxicological endpoints.
• To assess the environmental safety of 2-acetylthiazole based on PBT criteria and risk quotients.
• To confirm the safe use of 2-acetylthiazole in fragrance applications.

Main Methods:

• Genotoxicity assays were performed.
• Skin sensitization was assessed using the dermal sensitization threshold (DST).
• Repeated dose, reproductive, and local respiratory toxicity were evaluated using the threshold of toxicological concern (TTC).
• Phototoxicity/photoallergenicity was determined by UV spectra analysis.
• Environmental safety was assessed against IFRA standards, including PBT evaluation and PEC/PNEC ratio calculation.

Main Results:

• 2-Acetylthiazole demonstrated no genotoxicity.
• Exposure levels were below the DST for skin sensitization.
• Exposure levels were below the TTC for repeated dose, reproductive, and local respiratory toxicity.
• 2-Acetylthiazole is not expected to be phototoxic or photoallergenic.
• The material is not persistent, bioaccumulative, and toxic (PBT), with environmental risk quotients <1.

Conclusions:

• The existing data support the safe use of 2-acetylthiazole as described in the safety assessment.
• 2-Acetylthiazole meets safety requirements for toxicological and environmental endpoints.
• The fragrance ingredient can be used with confidence based on the evaluated safety profile.