RIFM fragrance ingredient safety assessment, butyl lactate, CAS registry number 138-22-7.

The existing information supports the use of this material as described in this safety assessment. Butyl lactate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog ethyl (L)-lactate (CAS # 687-47-8) show that butyl lactate is not expected to be genotoxic. Data on read-across materials butyl alcohol (CAS # 71-36-3) and lactic acid (CAS # 50-21-5) provide a calculated margin of exposure (MOE) > 100 for the repeated dose and reproductive toxicity endpoints. The skin sensitization endpoint was completed using the dermal sensitization threshold (DST) for non-reactive materials (900 µg/cm2); exposure is below the DST. The phototoxicity/photoallergenicity endpoints were evaluated based on ultraviolet (UV) spectra; butyl lactate is not expected to be phototoxic/photoallergenic. Data on butyl lactate provide a calculated MOE >100 for the local respiratory endpoint. The environmental endpoints were evaluated; butyl lactate 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.

RIFM fragrance ingredient safety assessment, ethyl lactate, CAS registry number 97-64-3.

The existing information supports the use of this material as described in this safety assessment. Ethyl lactate was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data on ethyl lactate show that ethyl lactate is not genotoxic and provided a calculated Margin of Exposure (MOE) > 100 for the repeated dose toxicity, reproductive toxicity, and local respiratory endpoints. Data from ethyl lactate and additional material ethyl (L)-lactate (CAS # 687-47-8) show that there are no safety concerns for ethyl lactate for skin sensitization under the current declared levels of use. The phototoxicity/photoallergenicity endpoints were evaluated based on ultraviolet (UV) spectra; ethyl lactate is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; ethyl lactate 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.

Safety assessment of lactate esters.

Lactate esters have an oral LD50 greater than 2000 mg/kg and the inhalation LC50 is generally above 5000 mg/m3 and they may be potential eye and skin irritants, but not skin sensitizers. No evidence of teratogenicity or maternal toxicity was observed in an inhalation (2-ethylhexyl-l-lactate) or dermal study (ethyl-l-lactate). Subacute inhalation studies have been conducted at concentration up to 600 mg/m3 or higher on four lactate esters (ethyl, n-butyl, isobutyl, and 2-ethylhexyl-l-lactate). Degenerative and regenerative changes in the nasal cavity were noted in all studies. The NOAEL in ethyl, n-butyl, and isobutyl-l-lactate vapor studies was 200 mg/m3. For aerosol exposure, 2-ethylhexyl-l-lactate, the most toxic of the lactates, minimal damage to the nasal epithelium was noted at 75 mg/m3 with vapor being slightly less toxic than the aerosol. Lactates do not appear to cause systemic toxicity, except at very high concentrations (1800 mg/m3 or higher). These systemic effects may be secondary to severe irritation seen at high doses. Sensory irritation tests suggest that a vapor exposure limit of 75 mg/m3 ( approximately 15 ppm) should prevent irritation in humans and therefore an occupational exposure level for vapor of 75 mg/m3 is recommended. However, aerosol exposure should be kept as low as possible. The low vapor pressure of the higher molecular weight esters would tend to keep vapor exposure low and the odor of lactate esters serves as a warning of exposure. These lactate esters are readily biodegradable, suggesting little concern from an environmental point of view.