cis-hex-3-en-1-yl methyl carbonate

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:

January 2017

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

Justification for type of information:

The executive summary of the prediction is in the present section. The full justification can be found in the attached file of the study record.
Executive summary:
The acute Daphnia EC50 for the ester Liffarome is predicted to be 10.3 mg/L based on the ECOSAR SAR for esters using an measured log Kow of 3.0, molecular weight of 158.2 and the equation: Log 48h-LC50 (mmol/L) = -0.6305 (log Kow) + 0.7049. The LC50 in ECOSAR is considered equivalent to the EC50 as defined in OECD TG 202.
Liffarome is in the applicability domain of the ECOSAR prediction because: a) Liffarome is an ester presenting the toxicity solely by its bioavailability (i.e. without fragments that activate this ester); b) its log Kow is 3.0 (=< 5); c) its MW is 158.2 (< 1000); and; d) the toxicity predicted is below its measured water solubility of 134.7 mg/L.
The measured and predicted log Kows of Liffarome are quite similar (3.0 and 2.47, respectively; in view of the difference >0.5, the measured value one will be used). The closest analogue available in the ECOSAR training set is 2-Ethylhexyl lactate (CAS # 6283-86-9 with a Log Kow of 2.69 and molecular weight of 202) which has an experimental toxicity of 83 mg/L and an ECOSAR prediction of 20.6 mg/L. This further presents the limited uncertainty of the prediction for 2-Ethylhexyl lactate and thus also for Liffarome.
The fit in the applicability domain and the availability of an analogue in the training set results in limited uncertainty of the Liffarome prediction. This shows that the prediction is reliable and a Klimisch 2 can be assigned. 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.

Qualifier:

according to guideline

Guideline:

other: IR/CSR Guidance R.6 QSARs and grouping of chemicals, May 2008

Version / remarks:

In the QMR attached the model specifications are presented. In this QMR is referenced to the Methodology document for the ecological Structure-Activity Relationship model (ECOSAR) Class Programm MS Windows v1.1'. United States Environmental Protection Agency, Office of Pollution Prevention and Toxics, Washington DC (2011).

Deviations:

not applicable

GLP compliance:

no

Specific details on test material used for the study:

SMILES: O=C(OC)OCCC=CCC

Test organisms (species):

Daphnia sp.

Water media type:

freshwater

Total exposure duration:

48 h

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

10.3 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: QSAR predicted value

ECOSAR v1.11 predicted that the 48h-EC50 of Liffarome PFG to Daphnia is 10.3 mg/L.

Validity criteria fulfilled:

yes

Remarks:

The ECOSAR-Ester equation is valid when using the OECD criteria. In addition, N=40 and R2 is 0.80

Conclusions:

ECOSAR v1.11 predicted that the 48h-EC50 of Liffarome PFG to Daphnia is 10.3 mg/L.

Executive summary:

See Justification of information section.

Description of key information

Acute daphnia test, according to ECOSAR ester (Q)SAR model: EC50 = 10.3 mg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

10.3 mg/L

Additional information

The executive summary is presented in the Justification of Information section in the study record.