2-heptylcyclopentanone

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:

September 2016

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 full justification is presented in the attached files of this study record.
Executive summary: The acute algae ErC50 for the neutral organic substance Fleuramone is predicted to be 2.6 mg/L based on the ECOSAR SAR for neutral organics using an estimated log Kow of 4.0, molecular weight of 182.3 and the equation: Log 96h-EC50 (mmol/L) = -0.6922 log Kow + 0.9253
Fleuramone is in the applicability domain of the ECOSAR prediction because: a) Fleuramone is a neutral organic substance presenting the toxicity solely by its bioavailability (i.e. without fragments that activate this neutral organic substance); b) its log Kow is 4.0 (=< 6.4); c) its MW is 182.3 (< 1000); and; d) the toxicity predicted is below its measured water solubility of 31 mg/L.
The measured log Kow of Fleuramone is similar to the predicted one (3.8 versus 4.0, respectively). The measured acute algae information from Log Kow related substances in the ECOSAR training set and in the IFF fragrance types of Neutral Organics present similar EC50 values and therefore there is no remaining uncertainty. The fit in the applicability domain and the availability of a substance with a similar Log Kow in the training set results in limited uncertainty of the Fleuramone 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 algae toxicity on neutral organics (see attached report). The adequate and reliable documentation, attached in the study record, 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(C(CC1)CCCCCCC)C1

Test organisms (species):

Daphnia sp.

Water media type:

freshwater

Total exposure duration:

48 h

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

1.6 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: QSAR predicted value

Remarks:

ECOSAR Class: Neutral organics

ECOSAR v1.11 predicted that the 48h-EC50 of Fleuramone to Daphnia is 1.6 mg/L.

Validity criteria fulfilled:

yes

Remarks:

Criteria of Annex XI 1.3 are met. In addition, the n=>=4 and r2>= 0.7; N=98 and R2 is 0.77, respectively

Conclusions:

The acute toxicity of Fleuramone to Daphnia, EC50, is 1.6 mg/l using ECECOSAR v1.11 Neutral Organics using the predicted log Kow of 3.8.

Executive summary:

The executive summary is presented at the Justification of Information section of this record.

Description of key information

The EC50 Daphnia for Fleuramone is 1.6 mg/l using ECOSAR Neutral organics equation using the predicted log Kow of 4.0.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1.6 mg/L

Additional information

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

A supporting study was performed to assess the acute toxicity of the substance to Daphnia magna. The study was conducted under static conditions following the procedure described in OECD Guideline for Testing of Chemicals No. 202.

Groups of twenty daphnids (less than 24 hours old) were exposed for 48 hours to a control and 4 dilutions of a filtered substance extracts in test water (loading rate of stock solution = 17 mg/L; nominal test concentrations reported as 0.63-5.0 mg/L). The incidence of immobilisation was recorded for each test and control group after 24 and 48 hours. The 48 h EC50 value was 2.2 mg/L, based on nominal concentrations. Nominal concentrations were not sufficiently verified by chemical analysis. In fact, the reported recovery of test substance in the highest test concentration (non-specific TOC analysis) was 78% of nominal, at test start, but TOC measurement indicated a ca. 50% decrease of test substance at test end. Therefore the reported result should be considered only as indication for acute toxicity towards daphnids. The study is considered reliable with restrictions (Klimisch 2).