Propanoic acid, 2-hydroxy-, C12-13-branched alkyl esters

Endpoint summary

Additional information

Acute tests evaluating the toxicity of Propanoic acid, 2-hydroxy-, C12-13-branched-alkyl esters to fish, aquatic invertebrates and algae are available. No short-term effects on fish were observed up to a nominal loading rate of 100 mg/L while testing Water Accommodated Fractions (WAFs). Effects were observed in the available short-term toxicity studies to aquatic invertebrates and algae only at nominal loading rates above the water solubility. Therefore, it is likely that the effects may have been caused by an oversaturation of test solutions. It might be possible that a component of the UVCB substance tends to from micro-micelles with increasing loading rates. They are capable to pass through the filter due to the small size and can cause physical effects. A long-term study with aquatic invertebrates according to OECD 211 was considered for the final assessment on the chronic toxicity. This study resulted in a NOELR (21 d) of 0.11 mg/L (measured, initial) based on mobility. Propanoic acid, 2-hydroxy-, C12-13-branched-alkyl esters did not cause inhibition of biodegradation in a study according to OECD 301 F with activated sludge microorganisms (NOEC (28 d) ≥ 40 mg/L). Thus, the overall potential to cause inhibition of activated sludge microorganisms is low and significant inhibition of the subsequent degradation process in sewage treatment plants is not expected. As there were no effects observed up to the limit of water solubility in fish and no indications that fish is the most sensitive species it is not deemed necessary to perform an additional long-term study with fish.