Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

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 85% 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.

The Key study for each endpoint, which is the most relevant and reliable study result from across the main Alcohols, C20-30 (even numbered), constituents, is summarised below. No reliable toxicity data is available for aquatic plants, however a waiver is applicable for that endpoint.

 

Short-term Toxicity to Fish

The short-term toxicity in fish of components of Alcohols, C20-30 (even numbered), has been documented within this dossier. Adequate reliable measured data exists for short-term toxicity to fish to substances that are themselves constituents of as well as analogous to the primary components of the substance. In a conservative approach the most sensitive study result from across these substances have been identified and used to address the hazard endpoint in question. The most sensitive study result from across the substances has been identified as a reliable study with octadecan-1-ol (Wetton 1996), which reports an LC50 for short term toxicity in fish of >0.4 mg/L, which greater than the limit of solubility (LoS).

 

Long-term Toxicity to Fish

In accordance with REACH Annex XI, section 1, testing does not appear scientifically necessary for Annex endpoint 9.1.6. Sufficient information is available to predict an absence of toxicity at the limit of solubility for linear alcohols with carbon chain lengths ≥C15. Moreover, from experience gained in tests that have been conducted with substances in this category, considerable technical difficulties would be expected in the conduct of such a test, due to the very rapid biotic removal of the substance from the test system. Therefore, long-term toxicity to fish requirements are waived based on technical testing difficulties, ready biodegradation and low to no short-term toxicity to aquatic organisms at the limit of solubility. No reliable measured or predicted long-term toxicity data to fish for constituents of Alcohols, C20-30 (even numbered), is available.

 

Short-term Toxicity to Invertebrates

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 constituents and/or analogous long chain alcohols has been identified and used to address the hazard endpoint in question. The most sensitive study result from docosan-1-ol and icosan-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.

 

Long-term Toxicity to Invertebrates

In accordance with REACH Annex XI, section 1, testing does not appear scientifically necessary for Annex endpoint 9.1.5. Sufficient information is available to predict an absence of toxicity at the limit of solubility for linear alcohols with carbon chain lengths ≥C15 (Schaefer, 2005). Moreover, from experience gained in tests that have been conducted with substances in this category, considerable technical difficulties would be expected in the conduct of such a test, due to the very rapid biotic removal of the substance from the test system. Therefore, long-term toxicity to invertebrate requirements are waived based on technical testing difficulties, ready biodegradation and no short-term toxicity to aquatic organisms at the limit of solubility. No reliable measured or predicted long-term toxicity data to invertebrates for constituents of Alcohols, C20-30 (even numbered), are available.

 

Toxicity to Aquatic Algae

The toxicity to algae of components of Alcohols, C20-30 (even numbered), has been documented within this dossier. Adequate reliable predicted data exists for toxicity to algae 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 from these substances has been identified and used to address the hazard endpoint in question. These substances are considered non-toxic at the limit of solubility. Therefore, the value used as key in the assessment is the EC50 of >0.001 mg/L which is at the limit of solubility for both docosan-1-ol and icosan-1-ol. 

 

Toxicity to Microorganisms

Study data, where available, for the primary constituents of Alcohols, C20-30 (even numbered), have been evaluated and considered together. In a conservative approach the most sensitive study result from substances that are constituents of and/or analogous to the primary constituents has been identified and used to adequately address the Alcohols, C20-30 (even numbered), endpoint in question. 

 

In accordance with Column 2 of REACH Annex VIII, the activated sludge respiration inhibition study (required in Section 9.1.4) does not need to be conducted as the substance is readily biodegradable and the applied test concentrations are in the range that can be expected in the influent to a sewage treatment plant. The most sensitive study result across the substances that are constituents of or analogous to constituents of Alcohols, C20-30 (even numbered), was used to represent the toxicity of the test substance.