D,L-DIETHYL TARTRATE

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:

From 30 November 2015 to 01 December 2015

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model, but not (completely) falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
iSafeRat® HA-QSAR

2. MODEL (incl. version number)
iSafeRat® holistic HA-QSAR v1.5

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
O=C(OCC)C(O)C(O)C(=O)OCC
The water solubility of the substance predicted using the iSafeRat® solubility module was given as input : 1,41.10^6 mg/L

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See attached QMRF

5. APPLICABILITY DOMAIN
See attached QMRF

6. ADEQUACY OF THE RESULT
See attached QPRF

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

not applicable

Remarks:

(QSAR model)

Principles of method if other than guideline:

The acute toxicity to aquatic invertebrates was determined using a validated QSAR for the Mode of Action in question, based on validated data derived from 48-hour EC50 tests on daphnia, for which the concentrations of the test item had been determined by chemical analyses over the test period. The QSAR is a simple linear regression of sub-cooled liquid solubility versus 48-h EC50 for daphnia and is valid within the applicability domain defined in the QMRF.

GLP compliance:

no

Specific details on test material used for the study:

No additional information

Analytical monitoring:

no

Details on sampling:

Not applicable

Vehicle:

no

Details on test solutions:

Not applicable

Test organisms (species):

Daphnia magna

Details on test organisms:

Not applicable

Test type:

other: QSAR

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

none

Post exposure observation period:

Not applicable

Hardness:

The QSAR is based on data from studies performed at acceptable hardness to ensure control survival.

Test temperature:

The temperatures varied from approximately 20 to 23 °C depending on the species used to construct the algorithm. This small difference is not expected to contribute to the variability of the EC50 values found in experimental data.

pH:

The QSAR is based on data from studies performed at acceptable pH between 6.0 - 9.0.

Dissolved oxygen:

The QSAR is based on data from studies performed at acceptable oxygen concentrations (generally >60%).

Salinity:

Not applicable.

Nominal and measured concentrations:

The QSAR is based on data from studies performed using measured concentrations or with acceptable stability.

Details on test conditions:

Not applicable

Reference substance (positive control):

no

Remarks:

QSAR model

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

368 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL: 139 - 972 mg/L

Details on results:

As per the iSafeRat® cascade approach (discussed in the iSafeRat® QMRF for the holistic approach, version 1.5), the subcooled liquid water solubility of a substance is strongly correlated to the ecotoxicity at different trophic levels. The toxicity to algae (72h-ErC50), which has been calculated as 81 mg/L using the predicted water solubility value (1.41.10^6 mg/L), was found to be conversative compared to the experimental study result of 369.3 mg/L. As all the endpoints within the holistic approach are interlinked, the predicted value of 368 mg/L for 48h-EC50 in daphnid is also expected to be conservative compared to the experimental result.

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

95% CL: 139 - 972 mg/L
QSAR statistical parameters are given in the QMRF and the QPRF

No additional information

Validity criteria fulfilled:

yes

Conclusions:

The 48-h EC50 value based on mobility and measured concentrations was determined to be 368 mg/L with 95%-Confidence Limit between 139 and 972 mg/L.

Executive summary:

A QSAR prediction was performed to assess the acute toxicity of the test substance to daphnid. This QSAR has been validated to be compliant with the OECD recommendations for QSAR modelling (OECD, 2004) and predicts the endpoint value which would be expected when testing the substance under experimental conditions in a laboratory following OECD Guideline 202. The criterion predicted was the EC50 (Median Effective Concentration), a statistically derived concentration which is expected to cause immobility in 50% of test animals within a period of 48 hours.

 

The immobility of the daphnids was determined using a validated QSAR for the Mode of Action in question (ester). The QSAR is based on validated data for a training set of 12 chemicals derived from 48-hour tests on daphnids, for which the concentrations of the test substance had been determined by chemical analyses over the test period. The water solubility of the substance given as input was predicted using the iSafeRat solubility module at 1,41.10^6 mg/L.

The 48-h EC50 value based on mobility and measured concentrations was determined to be 368 mg/L with 95%-Confidence Limit between 139 and 972 mg/L. The toxicity to algae (72h-ErC50), which has been calculated as 81 mg/L using the predicted water solubility value (1.41.10^6 mg/L), was found to be conversative compared to the experimental study result of 369.3 mg/L. As all the endpoints within the holistic approach are interlinked, the predicted value of 368 mg/L for 48h-EC50 in daphnid is also expected to be conservative compared to the experimental result.

Description of key information

QSAR, iSafeRat holistic approach v1.5, key study, validity 2:

48h-EC50 (Daphnia magna) = 368 mg/L (95% CL: 139 - 972 mg/L).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

368 mg/L

Additional information

To assess the short-term toxicity of the registered substance to aquatic invertebrates, one QSAR prediction is available.

The QSAR model (iSafeRat® holistic HA-QSAR v1.5), performed on the registered substance to assess the acute toxicity of the test substance to daphnid, has been validated to be compliant with the OECD recommendations for QSAR modelling (OECD, 2004) and predicts the endpoint value which would be expected when testing the substance under experimental conditions in a laboratory following OECD Guideline 202. The criterion predicted was the EC50 (Median Effective Concentration), a statistically derived concentration which is expected to cause immobility in 50% of test animals within a period of 48 hours. The immobility of the daphnids was determined using a validated QSAR for the Mode of Action in question (ester). The QSAR is based on validated data for a training set of 12 chemicals derived from 48-hour tests on daphnids, for which the concentrations of the test substance had been determined by chemical analyses over the test period. The water solubility of the substance given as input was predicted using the iSafeRat solubility module at 1,41.10^6 mg/L. The 48-h EC50 value based on mobility and measured concentrations was determined to be 368 mg/L with 95%-Confidence Limit between 139 and 972 mg/L.

In conclusion, as the same QSAR model was validated for the "toxicity to aquatic algae" endpoint with an experimental study and the results from this prediction was observed to be conservative compared to those obtained from the experimental study, this result can be used for the "short-term toxicity to aquatic invertebrates" endpoint. Therefore, the 48h-EC50 value on daphnid was considered to be 368 mg/L (95% CL: 139 - 972mg/L).