Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Acute toxicity based on study data

Fish: LC50 (96h) = 108 mg/L for Danio rerio

Crustacea: EL50 (48h) = 51 mg/L for Daphnia magna

Algae: EL50 (72h) > 10 mg/L for Pseudokirchneriella subcapitata

Chronic toxicity based on alcohol ethoxylate specific QSARs

Fish: EC20 (30d) = 0.464 mg/L for Pimephales promelas

Crustacea: EC20 (21d) = 0.150 mg/L for Daphnia magna

Algae: ErC20 (72h) = 0.322 mg/L for Desmodesmus subspicatus

Additional information

Category information on the aquatic hazard and risk assessment of alcohol ethoxylate

The toxicity mechanism for alcohol ethoxylates is accepted to be non-polar narcosis (Boeije et al. 2006), in which the AE homologues with longer hydrocarbon chains and higher log Kow are more efficient at penetration of the cell membrane, and thus more toxic. However, the alcohol ethoxylates homologues must be sufficiently soluble in water to allow a toxic concentration to reach the target organism. For the long chain alcohols (hydrocarbon chain lengths of 15 and above) the toxicity is restricted by solubility considerations. The available toxicity data follows this generally accepted pattern, and also indicates that the linear, essentially linear and branches AE are of similar toxicity (HERA, 2009).

Since long-term data are not available for all category members, precise long-term effect values were calculated with alcohol ethoxylate specific QSARs (Wind & Belanger, 2006; Boeije et al., 2006; Belanger et al., 2006). The used QSARs allow describing the toxicity for each registered mixture based on their individual composition. The effects are described as EC20 values, since the QSARs are more robust for the EC20 values than for NOEC or EC10 values (Boeije et al., 2006). As usual the lowest long-term value is used as key value for classification and labelling.

More details on the category approach are given in a separate document (see attached IUCLID chapter 13).