Octahydro-2H-1-benzopyran-2-one

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2016-2017

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 QSAR prediction is presented here. The full documentation is presented in the accompanying files attached to this record.

The acute Fish LC50 for the ester substance Bicyclononalactone is predicted to be 38 mg/L based on the ECOSAR SAR for esters using an estimated log Kow of 1.55, molecular weight of 154.21 and the equation: Log 96h-LC50 (mmol/L) = -0.584 (log Kow) + 0.2941.Bicyclononalactone is in the applicability domain of the ECOSAR prediction because: a) Bicyclononalactone is an ester presenting the toxicity solely by its bioavailability (i.e. without fragments that activate this ester); b) its log Kow is 1.55 (=< 5); c) its MW is 154.21 (< 1000); and; d) the toxicity predicted is below its measured water solubility of 39953 mg/L. The measured and predicted log Kows are sufficiently in line and do not indicate uncertainty in the prediction. The measured LC50 values in one of the ECOSAR training set data with a similar log Kow and the measured versus the predicted LC50 values for the fragrance types of esters (see QMR) present similar uncertainty as what can be expected during experimental testing.
The fit in the applicability domain and the limited uncertainty of the Bicyclononalactone prediction show 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 Fish 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(C(CCC1)C2)C1)C2

Test organisms (species):

not specified

Water media type:

freshwater

Total exposure duration:

96 h

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

38 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: QSAR predicted value; ECOSAR class:Esters

Sublethal observations / clinical signs:

ECOSAR v1.11 predicted that the 96h-LC50 of Bicyclononalactone is 38 mg/L.

Validity criteria fulfilled:

yes

Remarks:

The ECOSAR-Ester equation is valid when using the OECD criteria. In addition, N=87 and R2 is 0.79

Conclusions:

ECOSAR v1.11 predicted that the 96h-LC50 of Bicyclononalactone is 38 mg/L

Executive summary:

See justification of information.

Description of key information

The LC50 fish of the substance is 38 mg/L using ECOSAR ester equation.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

38 mg/L