Reaction mass of (R*,R*)-7-methoxy-3,7-dimethyl-2-octanol and (R*,S*)-7-methoxy-3,7-dimethyl-2-octanol

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:

2016-10-13 to 2016-10-14

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

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

Calculation method

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

yes

Remarks:

Calculation method

Principles of method if other than guideline:

The acute toxicity to fish was determined using a validated QSAR for the Mode of Action in question, i.e. non-polar narcosis (MOA1). The QSAR is based on validated data for a training set of 67 chemicals derived from 96-hour test on fish, for which the concentrations of the test item had been determined by chemical analyses over the test period.

GLP compliance:

no

Analytical monitoring:

no

Details on sampling:

Not applicable

Vehicle:

no

Details on test solutions:

Not applicable

Test organisms (species):

other: Results from the following species were used in the regression: Danio rerio, Oncorhynchus mykiss, Lepomis macrochirus, Pimephales promelas, Oryzias latipes, Leuciscus idus

Details on test organisms:

Following the principles of Phase Equilibrium Thermodynamics, for narcotic substances, no difference in relationship between solubility and ecotoxicity between fish freshwater species is expected. Any observed differences may be attributed to lifestyle related parameters (e.g. relative differences in storage lipid content between species) and relative duration of study versus bodysize rather than to a specific toxic mechanism causing species differences. In this case, for non-polar narcotic compounds, no differences were observed in activity based toxicity for the species used.

Test type:

other: QSAR

Water media type:

not specified

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

Not applicable

Hardness:

No data

Test temperature:

The temperatures varied from approximately 14 to 25 °C depending on the fish species used to construct the algorithm. While it is recognized that this may
contribute to some extent to the variability of the LC50 values found in experimental data, KREATiS has not observed a clear trend suggesting that normalization to temperature would necessarily improve the algorithm (say for trout as opposed to warm water species) for monoconstituents. Nevertheless, this is a recognized area for further research by KREATiS.

pH:

Test results were taken from studies with measured pHs between 6.0 - 8.5.

Dissolved oxygen:

The dissolved oxygen concentration was more than 60% of the air-saturation value throughout the duration of the test. In exceptional cases where studies with oxygen concentrations lower than 60% were used, all aspects of the study were thoroughly evaluated in order to satisfy the evaluator that the effects found were not due to reduced oxygen concentration (i.e. the study would correctly receive a Klimisch score of 2 under the REACH Regulation [REACH, 2006])

Salinity:

No data

Conductivity:

No data

Details on test conditions:

Only results from a test duration of 96 hours were included. A variety of test designs were accepted: Preferentially results from a semi-static with daily renewal of test solutions and the control or from a flow-through test were used. However, for stable, low volatility substances a static design was accepted(preferably accompanied by analytical measurements over the study period). For suspected volatile substances only tests performed in closed vessels were accepted unless accompanying analytical monitoring proved such a design was not necessary.

Reference substance (positive control):

not required

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

208 mg/L

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other:

Remarks:

95% CL: 188 - 229 mg/L

Details on results:

The predicated value is reliable since the test substance falls within the applicability domain of the model. The value of water solubility of the test substance is within descriptor domain of the model between log water solubility (in log (mol/L)) of -4.63 to -0.87. Moreover the test substance is attributed to the class of non-polar narcotic compounds.

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

Not applicable

Sublethal observations / clinical signs:

None

Validity criteria fulfilled:

yes

Conclusions:

The 96-hour LC50 for 7-methoxy 3,7-dimethyloctan-2-ol multiconstituent is 208 mg test item/L.

Executive summary:

A QSAR model was used to calculate the acute toxicity of test item 7-methoxy-3,7-dimethyloctan-2-ol multiconstituent to fish. This QSAR model has been validated to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) and predicts the endpoint value which would be expected when testing the substance under experimental conditions in a laboratory following Guideline for Testing of Chemicals No. 203, "Fish Acute Toxicity Test", referenced as Method C.1 of Commission Regulation No. 440/2008. The criterion predicted was the LC50 (Median Lethal Concentration), a statistically derived concentration which is expected to cause mortality in 50% of test animals within a period of 96 hours.

The acute toxicity to fish was determined using a validated QSAR for the Mode of Action in question, i.e. non-polar narcosis (MOA1). The QSAR is based on validated data for a training set of 67 chemicals derived from 96-hour test on fish, for which the concentrations of the test item had been determined by chemical analyses over the test period.

Based on measured concentrations, the predicted 96-hour LC50 has been determined to be 208 mg/L.

Description of key information

The 96-hour LC50 for 7-methoxy 3,7-dimethyloctan-2-ol multiconstituent is 208 mg test item/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

208 mg/L

Additional information

A QSAR model was used to calculate the acute toxicity of test item 7-methoxy-3,7-dimethyloctan-2-ol multiconstituent to fish. This QSAR model has been validated to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) and predicts the endpoint value which would be expected when testing the substance under experimental conditions in a laboratory following Guideline OECD 203.

The acute toxicity to fish was determined using a validated QSAR for the Mode of Action in question, i.e. non-polar narcosis (MOA1). The QSAR is based on validated data for a training set of 67 chemicals derived from 96-hour test on fish, for which the concentrations of the test item had been determined by chemical analyses over the test period.