Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
(Q)SAR
Adequacy of study:
key study
Study period:
2018
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification
Qualifier:
according to
Guideline:
other: REACH Guidance R.6: QSARs and grouping of chemicals. Version May 2008.
Deviations:
not applicable
GLP compliance:
no
Specific details on test material used for the study:
SMILES of Ethyl dodecanoate/laurate being representative for Oenanthic ether): O=C(OCC)CCCCCCCCCCC (
Test organisms (species):
other: Daphnia
Water media type:
freshwater
Total exposure duration:
48 h
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
1.456 mg/L
Nominal / measured:
estimated
Conc. based on:
test mat.
Basis for effect:
mortality
Remarks:
mobility
Remarks on result:
other: ECOSAR class: Esters
Validity criteria fulfilled:
yes
Remarks:
The ECOSAR-Esters equation is valid when using the OECD criteria. In addition, N=40 (+21) and R2 is 0.798
Conclusions:
Based on the ECOSAR v1.11 (Q)SAR, the predicted EC50 of Oenanthic ether to daphnids is 1.456 mg/L.
Executive summary:

The acute Daphnia EC50 for Oenanthic ether is predicted to be 1.456 mg/L based on the ECOSAR SAR for esters using a measured log Kow of 4.6 and the equation: Log 48-h LC50 (mmol/L) = -0.6305 (log Kow) + 0.7049. The 48-h LC50 is considered equivalent to the 48-h EC50 as defined in OECD TG 202. Though Oenanthic ether is a multi-constituent with alkyl chains varying between C8-C18, a single log Kow was derived in the HPLC, which is thought to be representing the main constituent of Oenanthic ether: Ethyl dodecenoate/laurate and has a C12 alkyl chain.

Oenanthic ether is in the applicability domain of the ECOSAR prediction because: a) Oenanthic ether is a chemical class presenting the toxicity solely by its bioavailability (i.e. without fragments that activate this chemical class); b) its log Kow is 4.6 (=< 5); c) its MW is < 1000 (< 1000); and; d) the toxicity predicted is below its measured water solubility of 1.6 mg/L.

A measured log Kow of 4.6 is entered as input for the calculation, because this log Kow value was the only peak found for Oenanthic ether in the log Kow chromatogram.

In accordance with REACH Annex XI, the validity of the (Q)SAR is documented in a QMR for acute Daphnia toxicity on esters (see attached report). The adequate and reliable documentation, presented below, further supports this prediction.

Description of key information

For Oenanthic ether an EC50 of 1.46 mg/l for Daphnia is derived, based on ECOSAR prediction using the determined log Kow of 4.6.

Key value for chemical safety assessment

EC50/LC50 for freshwater invertebrates:
1.46 mg/L

Additional information

The acute Daphnia EC50 for Oenanthic ether is predicted to be 1.456 mg/L based on the ECOSAR SAR for esters using a measured log Kow of 4.6 and the equation: Log 48-h LC50 (mmol/L) = -0.6305 (log Kow) + 0.7049. The 48-h LC50 is considered equivalent to the 48-h EC50 as defined in OECD TG 202. Though Oenanthic ether is a multi-constituent with alkyl chains varying between C8-C18, a single log Kow was derived in the HPLC, which is thought to be representing the main constituent of Oenanthic ether: Ethyl dodecenoate/laurate and has a C12 alkyl chain.

Oenanthic ether is in the applicability domain of the ECOSAR prediction because: a) Oenanthic ether is a chemical class presenting the toxicity solely by its bioavailability (i.e. without fragments that activate this chemical class); b) its log Kow is 4.6 (=< 5); c) its MW is < 1000 (< 1000); and; d) the toxicity predicted is below its measured water solubility of 1.6 mg/L.

A measured log Kow of 4.6 is entered as input for the calculation, because this log Kow value was the only peak found for Oenanthic ether in the log Kow chromatogram.

In accordance with REACH Annex XI, the validity of the (Q)SAR is documented in a QMR for acute Daphnia toxicity on esters (see attached report). The adequate and reliable documentation, presented below, further supports this prediction.