Reaction mass of ethyl dodecanoate and ethyl hexadecanoate and ethyl tetradecanoate

Short-term toxicity to aquatic invertebrates

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

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

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

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.