Lanolin, acetate

Endpoint summary

Description of key information

The substance is expected to undergo hydrolysis and metabolism but, considering the lack of acute (oral or dermal) or repeat dose toxicity, it is unlikely that metabolites of the registered substance present an additional toxicological hazard.

 

Key value for chemical safety assessment

Bioaccumulation potential:

no bioaccumulation potential

Additional information

No specific toxicokinetic (TK) investigations, or potential metabolite studies, were available at the time of review. However, a substantive volume of physical chemical and toxicity data exits from which a reasoned scientific opinion on the TK parameters (absorption, distribution, metabolism and excretion) of this substance may be derived.

 

The physio-chemical data demonstrate that this substance (a UVCB) is sparingly soluble in water (< 1.0E-03 g C/L at 20.0 ± 0.5 °C), highly lipophilic (partition coefficient: > 1.0E10, Log10 Pow > 10) and has a low vapour pressure (1.27E-02 Pa at 25 °C). These data strongly suggest that absorption of this substance via the GI tract and skin are likely to be significant. However, inhalation exposure (particle size not relevant) is unlikely to be either an issue or a major route of exposure and therefore of limited concern regarding significant systemic exposure. The data indicate that the substance may have the potential to be widely distributed in the body but have a limited potential for accumulation. Furthermore, the chemistry and physical chemical properties suggest that the substance is likely to undergo extensive metabolism, the liver and kidneys being the most likely major sites. As a result, it may be expected that excretion would be most likely via the urine and to a lesser extent in the faeces.

 

The substance will hydrolyse in the gut of organisms resulting in the original fatty acid or alcohol structures and their metabolites being produced. As a result, the lanolin fatty acids and lanolin alcohols are the substances representative of what will be available in humans and a read-across from these substances can thus be used to determine the potential toxicity of lanolin acetate. Based on this read-across, the substance is of remarkably low toxicity both acutely (oral or dermal, LD50 > 2000 mg/kg) or after repeat oral dosing (F0 systemic and reproductive, and F1 neonatal NOAEL≥1000 mg/kg bw/day). It is neither genotoxic nor a skin or eye irritant, and was shown not to be a skin sensitiser. As stated, the physio-chemical data suggest significant potential for both oral and dermal absorption and therefore systemic exposure. Exposure to the parent substance, and subsequent metabolism and metabolites was without obvious adverse toxicological consequences (e.g. no in vitro genotoxicity was seen presence of metabolic activation). As it may be reasonably anticipated that the hydrolysis products of the substance undergo metabolism, and considering the lack of acute (oral or dermal) or repeat dose toxicity, it is likely that metabolites of this substance do not present an additional toxicological hazard.