Alcohols, C20-30 (even numbered)

Short-term toxicity to aquatic invertebrates

Description of key information

The short-term toxicity in invertebrates of components of Alcohols, C20-30 (even numbered), has been documented within this dossier.  In a conservative approach the most sensitive study result from substances that are themselves constituents of as well as analogous to the primary the primary constituents of Alcohols, C20-30 (even numbered),  have been identified and used to address the hazard endpoint in question. The most sensitive study result from the two substances, icosan-1-ol and docosan-1-ol, has been identified as a reliable study with docosan-1-ol (Fisk et al. 2009) where the 96 hr LC50 was predicted at >100 mg/L.  However, the predicted LC50 is greater than the limit of solubility (>LoS, which is 0.1 mg/L). It is concluded that under circumstances when the predicted LC50 is greater than the LoS, the substance is not considered to be toxic.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

Alcohols, C20-30 (even numbered), is a UVCB substance that comprises several linear long chain alcohols, predominantly tetracosan-1-ol (C24), hexacosan-1-ol (C26), and octacosan-1-ol (C28). Together, these substances make up approximately 70% of the composition of Alcohols, C20-30 (even numbered).  Other constituents include, to a much lesser extent, secondary long chain alcohols and complex mixtures of long chain carboxylate esters. On this basis, study data, where available, for each of the long chain alcohol constituents has been evaluated and considered together; this is consistent with the Category approach applied for Long Chain Alcohols (LCA) under REACH.  In a conservative approach the most sensitive study result from the constituents of the LCA category have been identified and used to address the endpoint in question.

Several reliable (Klimisch 1 or 2) short-term toxicity studies in invertebrates have been conducted for substances that are themselves constituents of as well as analogous to the primary constituents of Alcohols, C20-30 (even numbered), and are included in this dossier. The reliable studies included for each of these substances is briefly described below. In a conservative approach the most sensitive study result will be used to address the hazard endpoint in question.

While there were no reliable measured data for short-term toxicity of icosan-1-ol to invertebrates, Fisk et al (2009) provided reliable (Klimisch 2) predicted results for short-term toxicity of icosan-1-ol to invertebrates using a validated QSAR model based on measured data available across the alcohols category and the Log Kow of the substance. Fisk et al. (2009) predicted a 96hr LC50 of >100 mg/L for short–term toxicity to invertebrates when exposed to icosan-1-ol. The result was compared to the limit of solubility (LoS) and for this substance the predicted LC50 is greater than the limit of solubility (>LoS, which is 0.001 mg/L). It is concluded that under circumstances when the predicted LC50 is greater than the LoS, the substance is not considered to be toxic.

Fisk et al. (2009) provided reliable (Klimisch 2) predicted results for the short-term toxicity of docosan-1-ol to Daphnia magna using a validated QSAR based on measured data available across the alcohols category and the Log Kow of the substance. Fisk et al. (2009) predicted a 96hr LC50 of >100 mg/L for short–term toxicity to Daphnia magna when exposed to docosan-1-ol. The result was compared to the limit of solubility (LoS) and for this substance the predicted LC50 is greater than the limit of solubility (>LoS, which is 0.001 mg/L). It is concluded that under circumstances when the predicted LC50 is greater than the LoS, the substance is not considered to be toxic.

The short-term toxicity in invertebrates of components of Alcohols, C20-30 (even numbered), has been documented within this dossier. Adequate reliable predicted data exists for short-term toxicity to invertebrates to substances that are themselves constituents of as well as analogous to the primary components of Alcohols, C20-30 (even numbered). In a conservative approach the most sensitive study result has been used to address the hazard endpoint in question. The most sensitive study result from across the two substances has been identified as a reliable study with docosan-1-ol (Fisk et al., 2009) where the 96 hr LC50 was predicted at >100 mg/L. However, the predicted LC50 is greater than the limit of solubility (>LoS, which is 0.001 mg/L). It is concluded that under circumstances when the predicted LC50 is greater than the LoS, the substance is not considered to be toxic.