1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane

Bioaccumulation: aquatic / sediment

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

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

Justification for type of information:

1.1 CAS number: 98222-50-5
1.2 EC number: 941-787-9
1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30
1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information
2.1: Date of QPRF: 27 February 2020
2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)
Endpoint: Bioconcentration factor (BCF)
Dependent variable: BCF (read-across)

3.2 Algorithm (OECD Principle 2)
Model or submodel name: ToxRead BCF
Model version: 0.23 beta
Reference to QMRF: There is no QMRF available. Information to ToxRead can be found at https://www.vegahub.eu
Predicted values (model result): Overall assessment NOT POSSIBLE
Predicted values (comments): -
Input for prediction: Smiles
Descriptor values: Log Kow = 8.304

3.3 Applicability domain (OECD Principle 3)
Domains
i. Software unable to conclude a value
ii. No alerts found.
iii. Fragments of the query compound have been found in the compounds of the training set but did not trigger an alert.
Structural analogues
i. CAS: 6731.36-8
ii. CAS: 78-48-8
iii. CAS: 2008-41-5
iv. Iv. CAS: 10496-18-1
Consideration on structural analogues: With 67.7%, the average similarity of the three compounds used for read across and which triggered the same alerts is considered moderate. The Log BCFs range between 1.15 and 4.02 with an average of 2.815.
3.4: The uncertainty of the prediction (OECD principle 4)
Uncertainty is indicated as the model was unable to determine a predicted value for the compound. Furthermore, due to the variance in results, with two out of four nearest compounds having BCF values above 2000 L/Kg, there is only moderate concordance between these values and the average value of all four compounds.
3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)
Read across based on structural similarities and structural alerts.
4 Adequacy (Optional)
4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment
4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.
4.3: Outcome: A predicted value was not provided by the software. However, using the average of the four similar compounds suggests a log BCF of 2.815, which can only be used an indicative value.
4.4 Conclusion: ToxRead provided no assessment and the average log BCF of the four most similar compounds suggests a BCF <2000 L/Kg.

Guideline:

other: No guideline followed.

Principles of method if other than guideline:

- Principle of test: QSAR prediction of the potential for bioaccumulation
- Short description of test conditions: n/a
- Parameters analysed / observed: Log BCF [L/kg

Type:

BCF

Value:

653.1 L/kg

Remarks on result:

other: The Log BCFs range between 1.15 and 4.02 with an average of 2.815. Uncertainty is indicated as the model was unable to determine a predicted value for the compound, and no alerts were highlighted. Furthermore, due to the variance in results, with two out

Details on results:

1.1 CAS number: 98222-50-5
1.2 EC number: 941-787-9
1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30
1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information
2.1: Date of QPRF: 27 February 2020
2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)
Endpoint: Bioconcentration factor (BCF)
Dependent variable: BCF (read-across)

3.2 Algorithm (OECD Principle 2)
Model or submodel name: ToxRead BCF
Model version: 0.23 beta
Reference to QMRF: There is no QMRF available. Information to ToxRead can be found at https://www.vegahub.eu
Predicted values (model result): Overall assessment NOT POSSIBLE
Predicted values (comments): -
Input for prediction: Smiles
Descriptor values: Log Kow = 8.304

3.3 Applicability domain (OECD Principle 3)
Domains
i. Software unable to conclude a value
ii. No alerts found.
iii. Fragments of the query compound have been found in the compounds of the training set but did not trigger an alert.
Structural analogues
i. CAS: 6731.36-8
ii. CAS: 78-48-8
iii. CAS: 2008-41-5
iv. Iv. CAS: 10496-18-1
Consideration on structural analogues: With 67.7%, the average similarity of the three compounds used for read across and which triggered the same alerts is considered moderate. The Log BCFs range between 1.15 and 4.02 with an average of 2.815.
3.4: The uncertainty of the prediction (OECD principle 4)
Uncertainty is indicated as the model was unable to determine a predicted value for the compound. Furthermore, due to the variance in results, with two out of four nearest compounds having BCF values above 2000 L/Kg, there is only moderate concordance between these values and the average value of all four compounds.
3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)
Read across based on structural similarities and structural alerts.
4 Adequacy (Optional)
4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment
4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.
4.3: Outcome: A predicted value was not provided by the software. However, using the average of the four similar compounds suggests a log BCF of 2.815, which can only be used an indicative value.
4.4 Conclusion: ToxRead provided no assessment and the average log BCF of the four most similar compounds suggests a BCF <2000 L/Kg.

Conclusions:

ToxRead provided no assessment and the average log BCF of the four most similar compounds suggests a BCF <2000 L/Kg.

Reference 2

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

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:

1.1 CAS number: 98222-50-5
1.2 EC number: 941-787-9
1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30
1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information
2.1: Date of QPRF: 27 February 2020
2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)
Endpoint: Bioconcentration factor
Dependent variable: BCF log(L/kg)

3.2 Algorithm (OECD Principle 2)
Model or submodel name: BCFBAF
Model version: V3.01
Reference to QMRF: There is no QMRF available. Information to BCFBAF can be found at https://www.epa.gov.
Predicted values (model result): Log BCF = 2.144 (BCF = 139.5 L/kg)
Predicted values (comments): -
Input for prediction: Smiles
Descriptor values: See software printout

3.3 Applicability domain (OECD Principle 3)
Domains
i. Target compound is within the estimation domain as described in the software for non ionic compounds: Log Kow: estimated 8.30 (Range: -1.37 – 11.26), MW: 322.6 (Range: 68.08 – 959.17)
ii. All fragments of the query compound have been found in the compounds of the training set and in the model respectively.
iii. SAR based on fragments
Structural analogues
BCFBAF does not provide information on structural analogues.
3.4: The uncertainty of the prediction (OECD principle 4)
Based on the reported values and the domain described by the model, there are no clear indications of uncertainty.
3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)
SAR based on structural classes
4 Adequacy (Optional)
4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment
4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.
4.3: Outcome: There is some confidence in the prediction as the target compound was within the parameters of the domain expressed within the software. The prediction is for a BCF of 139.5 L/Kg, indicating that the compound should not be considered bioaccumulative.
4.4 Conclusion: The prediction is considered to be reliable and will be used together with results from other QSARs in a weight of evidence.

Guideline:

other: No guideline followed

Principles of method if other than guideline:

- Principle of test: QSAR prediction of the potential for bioaccumulation
- Short description of test conditions: n/a
- Parameters analysed / observed: Log BCF [L/kg]

Type:

BCF

Value:

139.5 L/kg

Remarks on result:

other: BCF value based on QSAR prediction.

Details on results:

1.1 CAS number: 98222-50-5
1.2 EC number: 941-787-9
1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30
1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information
2.1: Date of QPRF: 27 February 2020
2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)
Endpoint: Bioconcentration factor
Dependent variable: BCF log(L/kg)

3.2 Algorithm (OECD Principle 2)
Model or submodel name: BCFBAF
Model version: V3.01
Reference to QMRF: There is no QMRF available. Information to BCFBAF can be found at https://www.epa.gov.
Predicted values (model result): Log BCF = 2.144 (BCF = 139.5 L/kg)
Predicted values (comments): -
Input for prediction: Smiles
Descriptor values: See software printout

3.3 Applicability domain (OECD Principle 3)
Domains
i. Target compound is within the estimation domain as described in the software for non ionic compounds: Log Kow: estimated 8.30 (Range: -1.37 – 11.26), MW: 322.6 (Range: 68.08 – 959.17)
ii. All fragments of the query compound have been found in the compounds of the training set and in the model respectively.
iii. SAR based on fragments
Structural analogues
BCFBAF does not provide information on structural analogues.
3.4: The uncertainty of the prediction (OECD principle 4)
Based on the reported values and the domain described by the model, there are no clear indications of uncertainty.
3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)
SAR based on structural classes
4 Adequacy (Optional)
4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment
4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.
4.3: Outcome: There is some confidence in the prediction as the target compound was within the parameters of the domain expressed within the software. The prediction is for a BCF of 139.5 L/Kg, indicating that the compound should not be considered bioaccumulative.
4.4 Conclusion: The prediction is considered to be reliable and will be used together with results from other QSARs in a weight of evidence.

Conclusions:

The prediction is considered to be reliable and will be used together with results from other QSARs in a weight of evidence.

Reference 3

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

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

Justification for type of information:

1.1 CAS number: 98222-50-5
1.2 EC number: 941-787-9
1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30
1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information
2.1: Date of QPRF: 27 February 2020
2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)
Endpoint: Bioconcentration factor (BCF) in fish
Dependent variable: BCF log(L/kg)

3.2 Algorithm (OECD Principle 2)
Model or submodel name: BCF model (Meylan) within VEGA 1.1.5
Model version: 1.0.3
Reference to QMRF: The corresponding QMRF VEGA BCF model (Meylan) is available from JRC QSAR Model Database (https://qsardb.jrc.ec.europa.eu/qmrf; ID: Q17-24a-0010)
Predicted values (model result):
Predicted BCF [log(L/kg)]: 2.14
Predicted BCF [L/kg]: 139
Predicted values (comments): According to VEGA’s evaluation scheme, the result shows some critical aspects, which require to be checked.
Input for prediction: Smiles
Descriptor values: Not provided by the software.

3.3 Applicability domain (OECD Principle 3)
Domains
i. According to VEGA’s evaluation scheme, the predicted compound could be out of the Applicability Domain of the model
ii. A prominent number of atom centered fragments of the compound have not been found in the compounds of the training set or are rare fragments
iii. Structural alerts: N/A
Structural analogues
i. CAS: 78-63-7
ii. CAS: 6731-36-8
iii. CAS: 4390-04-9
iv. CAS: 13475-82-6
With 67% the average similarity of the four most similar analogues in the training set to the query structure may be considered moderate. Predicted and actual value of the most similar structures vary by a factor of up 4.4 which is within a default factor of 10 often used in traditional risk assessment of environmental chemicals to compensate for uncertainties. Accuracy is therefore considered acceptable. Study values of two of the four the similar structures are in the same region as the predicted result for the query structure, thus indicating moderate concordance.
3.4: The uncertainty of the prediction (OECD principle 4)
Moderate concordance and moderate similarity with regard to the similar structures suggests some uncertainty, however accuracy was assessed to be acceptable suggesting some confidence in the prediction.

3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)
Not applicable since statistical model

4 Adequacy (Optional)
4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment
4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.
4.3: Outcome: The variance of predicted values to experimental values for the similar compounds within model is low, thus indicating confidence in the prediction. However, this confidence is undermined as the prediction has failed to meet the requirements of the applicability domain for the model. This is substantiated by only moderate similarity and concordance of results between the query compound and the four most similar compounds in the training set. Thus it is concluded that the prediction is of low reliability.
4.4 Conclusion: Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

Guideline:

other: No guideline followed

Principles of method if other than guideline:

- Principle of test: QSAR prediction of the potential for bioaccumulation
- Short description of test conditions: n/a
- Parameters analysed / observed: Log BCF [L/kg]

Type:

BCF

Value:

139.5 L/kg

Remarks on result:

other: BCF value based on QSAR prediction.

Details on results:

1.1 CAS number: 98222-50-5
1.2 EC number: 941-787-9
1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30
1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information
2.1: Date of QPRF: 27 February 2020
2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)
Endpoint: Bioconcentration factor (BCF) in fish
Dependent variable: BCF log(L/kg)

3.2 Algorithm (OECD Principle 2)
Model or submodel name: BCF model (Meylan) within VEGA 1.1.5
Model version: 1.0.3
Reference to QMRF: The corresponding QMRF VEGA BCF model (Meylan) is available from JRC QSAR Model Database (https://qsardb.jrc.ec.europa.eu/qmrf; ID: Q17-24a-0010)
Predicted values (model result):
Predicted BCF [log(L/kg)]: 2.14
Predicted BCF [L/kg]: 139
Predicted values (comments): According to VEGA’s evaluation scheme, the result shows some critical aspects, which require to be checked.
Input for prediction: Smiles
Descriptor values: Not provided by the software.

3.3 Applicability domain (OECD Principle 3)
Domains
i. According to VEGA’s evaluation scheme, the predicted compound could be out of the Applicability Domain of the model
ii. A prominent number of atom centered fragments of the compound have not been found in the compounds of the training set or are rare fragments
iii. Structural alerts: N/A
Structural analogues
i. CAS: 78-63-7
ii. CAS: 6731-36-8
iii. CAS: 4390-04-9
iv. CAS: 13475-82-6
With 67% the average similarity of the four most similar analogues in the training set to the query structure may be considered moderate. Predicted and actual value of the most similar structures vary by a factor of up 4.4 which is within a default factor of 10 often used in traditional risk assessment of environmental chemicals to compensate for uncertainties. Accuracy is therefore considered acceptable. Study values of two of the four the similar structures are in the same region as the predicted result for the query structure, thus indicating moderate concordance.
3.4: The uncertainty of the prediction (OECD principle 4)
Moderate concordance and moderate similarity with regard to the similar structures suggests some uncertainty, however accuracy was assessed to be acceptable suggesting some confidence in the prediction.

3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)
Not applicable since statistical model

4 Adequacy (Optional)
4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment
4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.
4.3: Outcome: The variance of predicted values to experimental values for the similar compounds within model is low, thus indicating confidence in the prediction. However, this confidence is undermined as the prediction has failed to meet the requirements of the applicability domain for the model. This is substantiated by only moderate similarity and concordance of results between the query compound and the four most similar compounds in the training set. Thus it is concluded that the prediction is of low reliability.
4.4 Conclusion: Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

Conclusions:

Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

Reference 4

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

3 (not reliable)

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:

1.1 CAS number: 98222-50-5
1.2 EC number: 941-787-9
1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30
1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information
2.1: Date of QPRF: 27 February 2020
2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)
Endpoint: Bioconcentration factor
Dependent variable: Bioconcentration factor (BCF) logL/kg

3.2 Algorithm (OECD Principle 2)
Model or submodel name: BCF Model (CAESAR) within VEGA 1.1.5
Model version: 2.1.14
Reference to QMRF: There is no QMRF available. Information to the VEGA models can be found at vega-qsar.eu

Predicted values (model result):
Predicted BCF [log(L/kg)]: 2.16
Predicted BCF [L/kg]: 144
Predicted BCF from sub-model 1 (HM) [log(L/kg)]: 2.13
Predicted BCF from sub-model 2 (GA) [log(L/kg)]: 2.16
Predicted LogP (MLogP): 5.52
Predicted values (comments): According to VEGA’s evaluation scheme, the predicted compound is outside the Applicability Domain of the model.
Input for prediction: Smiles
Descriptor values: Not provided by the software.

3.3 Applicability domain (OECD Principle 3)
Domains
i. According to VEGA’s evaluation scheme, the predicted compound could be out of the Applicability Domain of the model
ii. A prominent number of atom centered fragments of the compound have not been found in the compounds of the training set or are rare fragments
iii. Structural alerts: N/A
Structural analogues
i. CAS: 6731-36-8
ii. CAS: 4390-04-9
iii. CAS: 13475-82-6
iv. iv. CAS: 298-07-7

With 65% the average similarity of the four most similar analogues in the training set to the query structure is considered moderate. Predicted and actual value of the most similar structures vary by a factor of up 188 which is well above a default factor of 10 often used in traditional risk assessment of environmental chemicals to compensate for uncertainties. Accuracy is therefore considered low.
3.4: The uncertainty of the prediction (OECD principle 4)
Low accuracy and moderate similarity with regard to the similar structures suggest low confidence in the prediction.

3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)
Not applicable since statistical model

4 Adequacy (Optional)
4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment
4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.
4.3: Outcome: The variance of predicted values to experimental values for the similar compounds within model is large, thus indicating low confidence in the prediction. This is substantiated by only moderate similarity between the query compound and the four most similar compounds in the training set. Furthermore, the prediction has failed to meet the requirements of the applicability domain for the model. Thus it is concluded that the prediction is of low reliability.
4.4 Conclusion: Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

Guideline:

other: no guideline followed

Principles of method if other than guideline:

- Principle of test: QSAR prediction of the potential for bioaccumulation
- Short description of test conditions: n/a
- Parameters analysed / observed: Log BCF [L/kg]

Type:

BCF

Value:

144 L/kg

Remarks on result:

other: BCF value based on QSAR prediction.

Details on results:

1.1 CAS number: 98222-50-5
1.2 EC number: 941-787-9
1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30
1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information
2.1: Date of QPRF: 27 February 2020
2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)
Endpoint: Bioconcentration factor
Dependent variable: Bioconcentration factor (BCF) logL/kg

3.2 Algorithm (OECD Principle 2)
Model or submodel name: BCF Model (CAESAR) within VEGA 1.1.5
Model version: 2.1.14
Reference to QMRF: There is no QMRF available. Information to the VEGA models can be found at vega-qsar.eu

Predicted values (model result):
Predicted BCF [log(L/kg)]: 2.16
Predicted BCF [L/kg]: 144
Predicted BCF from sub-model 1 (HM) [log(L/kg)]: 2.13
Predicted BCF from sub-model 2 (GA) [log(L/kg)]: 2.16
Predicted LogP (MLogP): 5.52
Predicted values (comments): According to VEGA’s evaluation scheme, the predicted compound is outside the Applicability Domain of the model.
Input for prediction: Smiles
Descriptor values: Not provided by the software.

3.3 Applicability domain (OECD Principle 3)
Domains
i. According to VEGA’s evaluation scheme, the predicted compound could be out of the Applicability Domain of the model
ii. A prominent number of atom centered fragments of the compound have not been found in the compounds of the training set or are rare fragments
iii. Structural alerts: N/A
Structural analogues
i. CAS: 6731-36-8
ii. CAS: 4390-04-9
iii. CAS: 13475-82-6
iv. iv. CAS: 298-07-7

With 65% the average similarity of the four most similar analogues in the training set to the query structure is considered moderate. Predicted and actual value of the most similar structures vary by a factor of up 188 which is well above a default factor of 10 often used in traditional risk assessment of environmental chemicals to compensate for uncertainties. Accuracy is therefore considered low.
3.4: The uncertainty of the prediction (OECD principle 4)
Low accuracy and moderate similarity with regard to the similar structures suggest low confidence in the prediction.

3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)
Not applicable since statistical model

4 Adequacy (Optional)
4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment
4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.
4.3: Outcome: The variance of predicted values to experimental values for the similar compounds within model is large, thus indicating low confidence in the prediction. This is substantiated by only moderate similarity between the query compound and the four most similar compounds in the training set. Furthermore, the prediction has failed to meet the requirements of the applicability domain for the model. Thus it is concluded that the prediction is of low reliability.
4.4 Conclusion: Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

Conclusions:

Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

Reference 5

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

3 (not reliable)

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:

1.1 CAS number: 98222-50-5
1.2 EC number: 941-787-9
1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30
1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information
2.1: Date of QPRF: 27 February 2020
2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)
Endpoint: Bioconcentration factor
Dependent variable: Bioconcentration factor (BCF) log10 L/kg

3.2 Algorithm (OECD Principle 2)
Model or submodel name: US EPA T.E.S.T Bioconcentration factor, Consensus method
Model version: 4.2.1
Reference to QMRF: There is no QMRF available and provided by US EPA, respectively.

Predicted values (model result): 2.67 log L/kg (465.04 L/kg)
Predicted values (comments): BCF of the five methods ranges from 0.86 to 3.96 log L/kg.
Input for prediction: Smiles
Descriptor values: Due to the large number of descriptors used all information are attached in the software printout section.

3.3 Applicability domain (OECD Principle 3)
Domains
i. Query structure is out of the domain of the consensus model
ii. All descriptors of the query structure are within ranges
iii. Considerations on the mechanism domain are not applicable since statistical model

Structural analogues (training set)
i. CAS 10496-18-1
ii.CAS 4390-04-9
iii. CAS 732-26-3
iv. CAS 120-54-7
Consideration on structural analogues: With 57%, the average similarity between the four most similar structures in the training set and the query structure may be considered moderate. Predicted and experimental values of similar structures vary by a factor of up to 31.6 which is well above a default factor of 10 often used in traditional risk assessment of environmental chemicals to compensate for uncertainties*. Hence concordance between predicted and actual value (accuracy) is considered low.
3.4: The uncertainty of the prediction (OECD principle 4)
Moderate similarity and low accuracy indicate uncertainty. This is substantiated by a mean absolute error of the predictions with training set being greater than the mean absolute error of the entire set. Furthermore for the external test set, no chemicals in the test set exceed a minimum similarity coefficient of 0.5 for comparison purposes.

3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)

4 Adequacy (Optional)
4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment
4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.
4.3: Outcome: The range of predicted values within the consensus methods is large, thus indicating low confidence in the prediction. This is substantiated by only moderate similarity between the query compound and the four most similar compounds in the training set.
4.4 Conclusion: The predicted log BCF of 2.67 log L/kg (465.04 L/kg) is below the threshold of a substance being considered as bioaccumulative, i.e. 2000 L/kg. Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

Guideline:

other: No guideline followed

Type:

BCF

Value:

465.04 L/kg

Remarks on result:

other: BCF value based on QSAR prediction.

Details on results:

1.1 CAS number: 98222-50-5

1.2 EC number: 941-787-9

1.3 Chemical name
IUPAC: 1,3-bis(2,4,4-trimethylpentan-2-yl)trisulfane
Other: DAILUBE IS-30

1.5 Structure codes
SMILES: CC(C)(CC(C)(C)SSSC(C)(C)CC(C)(C)C)C
InChI: InChI=1S/C16H34S3/c1-13(2,3)11-15(7,8)17-19-18-16(9,10)12-14(4,5)6/h11-12H2,1-10H3
Stereochemical features: Not applicable

2: General Information

2.1: Date of QPRF: 27 February 2020

2.2: Author and contact details Jamie Marshall, Covance CRS Research Ltd., Shardlow, Derbyshire, DE72 2GD Email: [e-mail]

3 Prediction
3.1 Endpoint (OECD Principle 1)

Endpoint: Bioconcentration factor
Dependent variable: Bioconcentration factor (BCF) log10 L/kg

3.2 Algorithm (OECD Principle 2)
Model or submodel name: US EPA T.E.S.T Bioconcentration factor, Consensus method

Model version: 4.2.1
Reference to QMRF: There is no QMRF available and provided by US EPA, respectively.

Predicted values (model result): 2.67 log L/kg (465.04 L/kg)
Predicted values (comments): BCF of the five methods ranges from 0.86 to 3.96 log L/kg.

Input for prediction: Smiles
Descriptor values: Due to the large number of descriptors used all information are attached in the software printout section.

3.3 Applicability domain (OECD Principle 3)
Domains
i. Query structure is out of the domain of the consensus model
ii. All descriptors of the query structure are within ranges
iii. Considerations on the mechanism domain are not applicable since statistical model

Structural analogues (training set)
i. CAS 10496-18-1
ii.CAS 4390-04-9
iii. CAS 732-26-3
iv. CAS 120-54-7

Consideration on structural analogues: With 57%, the average similarity between the four most similar structures in the training set and the query structure may be considered moderate. Predicted and experimental values of similar structures vary by a factor of up to 31.6 which is well above a default factor of 10 often used in traditional risk assessment of environmental chemicals to compensate for uncertainties*. Hence concordance between predicted and actual value (accuracy) is considered low.

3.4: The uncertainty of the prediction (OECD principle 4)
Moderate similarity and low accuracy indicate uncertainty. This is substantiated by a mean absolute error of the predictions with training set being greater than the mean absolute error of the entire set. Furthermore for the external test set, no chemicals in the test set exceed a minimum similarity coefficient of 0.5 for comparison purposes.

3.5: The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5)

4 Adequacy (Optional)

4.1 Regulatory purpose: Bioconcentration factor endpoint for use in PBT assessment

4.2: Approach for regulatory interpretation of the model result
Unit conversion provided by the software.

4.3: Outcome: The range of predicted values within the consensus methods is large, thus indicating low confidence in the prediction. This is substantiated by only moderate similarity between the query compound and the four most similar compounds in the training set.

4.4 Conclusion: The predicted log BCF of 2.67 log L/kg (465.04 L/kg) is below the threshold of a substance being considered as bioaccumulative, i.e. 2000 L/kg. Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

Conclusions:

The predicted log BCF of 2.67 log L/kg (465.04 L/kg) is below the threshold of a substance being considered as bioaccumulative, i.e. 2000 L/kg. Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

Reference 6

Endpoint:

bioaccumulation in aquatic species: fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

20 Aug - 01 Oct, 1987

Reliability:

2 (reliable with restrictions)

Qualifier:

according to guideline

Guideline:

other: Bioconcentration Tests of Chemical Substances in Fish Body” prescribed in "About Test Methods for New Chemical Substances" (Kanpogyo Notification No. 5, Yakuhatsu Notification No. 615, and 49 Kikyoku Notification No. 392 dated July 13, 1974).

Version / remarks:

In compliance with the Standards for Testing Facilities Prescribed in Article 4 of the Order Determining Items

Deviations:

not specified

GLP compliance:

not specified

Specific details on test material used for the study:

Name: di-tert-nonyl polysulfide (S=2-6)
Structural formula: (C9H12)2-Sn (n= 2-6)
Molecular formula: C18H38Sn (n=2-6)
Molecular weight: 318.63-446.90
Purity: 97.3%
Appearance: yellow transparent viscous liquid
Specific gravity: d20,20: 1.0326
Solubility Water: ≤6.9 μg/L
Hexane: ≥100 g/L
Chloroform: ≥100 g/L
Ethyl acetate: ≥100 g/L
Methanol: 19 g/L
Partition coefficient (n-octanol/water): Log Pow = ≥5.88 (Re: documents referred to in measuring partition coefficients)
Storage condition: cool and dark place
Stability: IR absorption spectra of the test substance obtained before and after exposure were identical, indicating that the test substance was stable under the storage condition
Stability under the study condition: A preliminary study was conducted before starting exposure to confirm the stability of the test substance under the study condition.

Radiolabelling:

no

Details on sampling:

Analysis of the test water and test fishes
Mass spectrograms showed that the test substance is a mixture with 2-6 Sn.
In assaying the test substance in the present study, its components were assayed all together as a single peak by high performance liquid chromatography (HPLC) since it was difficult to assay each component.
Concentrations were reported based on the amount of the test substance added

Frequency of analysis
Test water was analyzed twice a week for a total of 12 times during the exposure period at both concentrations. One sample was analyzed each time.
Test fishes were analyzed 2, 3, 4 and 6 weeks after starting exposure (4 times) at both both concentrations. Two fishes were analyzed each time.

Analysis of test fish
Condition for column chromatography
Chromatography tube: 20 mmφ glass tube
Filler: 5% hydrous basic alumina (5 g) (filled with hexane)
Loading method: Dissolve samples in about 5 ml of hexane.
Elution method: Eluate 1: hexane 30 mL (including loaded volume)

Condition for column chromatography
Chromatography tube: 20 mmφ glass tube
Filler: 5% hydrous basic alumina (10 g) (filled with hexane)
Loading method: Dissolve samples in about 5 ml of hexane.
Elution method: Eluate 1: hexane 50 mL (including loaded volume)

Condition for column chromatography
Chromatography tube: 20 mmφ glass tube
Filler: 5% hydrous silica gel (5 g) (filled with hexane)
Loading method: Dissolve samples in about 5 ml of hexane.
Elution method: Eluate 1: hexane 30 mL (including loaded volume)

Quantitative analysis
Analytical equipment and conditions
Apparatus: high-performance liquid chromatograph
Column: 30 cm x 8 mm φ (stainless steel column)
TSK-GEL G1000HXL
Eluent: tetrahydrofuran
Flow rate: 1.0 mL/min
Wavelength: 294 nm
Injection vol: 90 μl

Recovery rates in analysis procedures
Analysis of the test water (50 μg of the test substance added):
0.5 mg/L: 95.7% and 90.5% (mean: 93.1%)
0.05 mg/L: 94.8% and 92.2% (mean: 93.5%)
Analysis of test fish (150 μg of the test substance added);
70.4% and 70.4% (mean: 70.4%)

Vehicle:

yes

Remarks:

HCO-40

Details on preparation of test solutions, spiked fish food or sediment:

Preparation of stock solution
Dispersant: HCO-40
Preparation method
To prepare stock solution, HCO-40 was distilled away after dissolving in acetone, which was dispersed after adding ion-exchange water.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM
- Common name: common carp
- Source: Sugishima Fish Farm (123-2, Gunchiku-ichiban-cho, Yatsushiro, Kumamoto, Japan)
- Length at study initiation: 9.6 cm
- Weight at study initiation: 21.6 g
- Fat content (mean): 4.6%
- Test vessel: 100-L glass vessel
- Feeding during test : yes
- Food type: pellet formula feed for common carp (Nippon Formula Feed Manufacturing Co., Ltd.)
- Amount: equivalent to about 2% of fish
- Frequency: daily in two installments

- Cultivation condition:
Period, etc.: Fishes were visually inspected upon arrival and those with abnormality were eliminated. After chemical bathing in acceptance vessel, fishes were reared for 3 days in running water.
Chemical bathing: Fishes were bathed in static water containing Terramycin Powder for Fisheries (50 mg/L; Pfizer Taito) and sodium chloride (7 g/L) for 24 hrs.

Acclimatization procedures
Fishes were acclimatized in an acclimatization vessel and those with abnormality were eliminated. Remaining ones were reared for 22 days at 25±2°C in running water. They were then transferred to a test vessel and reared for an additional 7 days or more in running water of the same temperature.

Route of exposure:

aqueous

Test type:

flow-through

Water / sediment media type:

other: Ground water

Total exposure / uptake duration:

ca. 6 wk

Hardness:

Not specified

Test temperature:

25±2°C

pH:

Not specified

Dissolved oxygen:

6.3-7.3 - 7.5 mg/L

TOC:

Not specified

Salinity:

Not specified

Conductivity:

Not specified

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open / closed
- Material, size, headspace, fill volume:
- Aeration:
- No. of organisms per vessel:
- No. of vessels per concentration (replicates): 12
- No. of vessels per control / vehicle control (replicates):
- Biomass loading rate:

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
- Particulate matter:
- Metals:
- Pesticides:
- Chlorine:
- Alkalinity:
- Ca/mg ratio:
- Conductance:
- Holding medium different from test medium:
- Intervals of water quality measurement:
- Intervals of test medium replacement:

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod:
- Light intensity:
- For OECD 305 part III (dietary exposure fish bioaccumulation), overall daily feeding rate used in the study:
- For OECD 305 part III (dietary exposure fish bioaccumulation), number of feeds per day (number of feeds daily ration split between):
- For OECD 305 part III (dietary exposure fish bioaccumulation), overall lipid content of spiked food before test start taking into account the contribution from the corn or fish oil vehicle, if used:
- For OECD 305 part III (dietary exposure fish bioaccumulation), overall lipid content of spiked food after end of exposure taking into account the contribution from the corn or fish oil vehicle, if used:

RANGE-FINDING / PRELIMINARY STUDY
- Test concentrations:
- Results used to determine the conditions for the definitive study:
- Other justification for choice of test concentrations:

Nominal and measured concentrations:

Nominal (mg/L): 0.05; 0.5

Reference substance (positive control):

not specified

Details on estimation of bioconcentration:

BCFs obtained were rounded off to 1 significant figure and 2 significant figures, respectively, using the JIS 8401-1961 method if BCFs obtained were <1 fold and ≥1 through <10-fold.

Conc. / dose:

ca. 0.5 mg/L

Temp.:

ca. 25 °C

Type:

BCF

Value:

> 0.3 - < 1.2 L/kg

Conc. / dose:

ca. 0.05 mg/L

Temp.:

ca. 25 °C

Type:

BCF

Value:

<= 3.3 L/kg

Details on kinetic parameters:

Not specified

Metabolites:

Not specified

Results with reference substance (positive control):

Not specified

Details on results:

Appearance of test fishes showed no abnormality.
Mean test substance concentrations in test water remained at about 90% of the nominal value.

Reported statistics:

Not specified

		Week 2	Week 3	Week 4	Week 6
0.5 mg/L	Test substance concentration (mg/L)	0.446	0.446	0.448	0.457
	Bioconcentration factor (L/kg)	≤0.3	≤0.3	0.6	0.8
		≤0.3	0.6	1.2	0.8
0.05 mg/L	Test substance concentration (mg/L)	0.0449	0.0449	0.0450	0.0457
	Bioconcentration factor (L/kg)	≤3.3	≤3.3	≤ 3.3	≤3.3
		≤3.3	≤ 3.3	≤3.3	≤ 3.3

Conclusions:

Result of Bioconcentration: Low bioconcentration

Description of key information

Introduction

It was requested that by the sponsor that an investigation be carried out to determine a predicted value for the bioconcentration factor (BCF) of the substance DAILUBE IS-30. The present in silico assessment was performed with four computational tools: TEST, VEGA, EPI Suite, and ToxRead.
In the Appraisal of (Q)SAR Modelling, result of each computational tool was discussed if applicable including statistical performance, mode of action, eventual metabolism and reliability. The results are summarized in the appraisal section below. For each tool, the QSAR Prediction Reporting Format (QPRF) section, if any, and the respective software printout section were provided.

A bioaccumulation study was conducted on a similar substance di-tert-nonyl polysulfide which can also be used as supporting data for the weight of evidence summary in addition to the QSAR results.

Appraisal of (Q)SAR Modelling

For the evaluation of the BCF of the compound, quantitative structure activity relationship (QSAR) modelling was performed using T.E.S.T. 4.2.1, VEGA NIC 1.1.5, BCF/BAF 3.01, and ToxRead 0.23 beta.
All results are reported in QSAR Prediction Reporting Formats (QPRFs). To maintain focus on the main points QSAR Model Reporting Formats (QMRFs) have not been attached to the document. For information on the US EPA T.E.S.T. and EPI Suite software, refer to US EPA website. Information to the VEGA models can be obtained from the VEGA website.

Software	Model	Predicted log10BCF	Predicted BCF (L/Kg)	Reliability
T.E.S.T. 4.2.1	Consensus	2.67	465.04	1
	CAESAR 2.1.14	2.16	144	1
VEGA 1.1.5	Meylan 1.03	2.14	139	1
	KNN/Read Across 1.1.0	No prediction	No prediction	0
EPI Suite 4.11	BCF/BAF v3.01	2.144	139.5	2
TOXREAD 0.23beta	IRFMN rule set for BCF	Not possible	Not possible	0
	Average of nearest compounds **	2.815	653.1	1

*Reliability score: where 3= High, 2=Moderate, 1=Low, and 0 = not reliable
** only indicative

T.E.S.T.
The consensus model for TEST predicted the query compound to possess a BCF value below the threshold for consideration as bioaccumulative. However the result is of low reliability for several reasons.
The average similarity between the four most similar structures in the training set and the query structure was determined to be 57% and may be considered moderate.
It was shown that there was a high degree of variance between the measured and predicted values for the nearest compounds in the training set, thus the concordance between predicted and actual value (accuracy) is considered low.
Moderate similarity and low accuracy indicate uncertainty. This is substantiated by a mean absolute error of the predictions with training set being greater than the mean absolute error of the entire set. Furthermore for the external test set, no chemicals in the test set exceeded the minimum similarity coefficient of 0.5.
Finally, of the available individual models from which the consensus derives its conclusion, only 4 of these 5 models were able to determine a value., and these are evenly split, with two predicting a value above the threshold for bioaccumulation, and two predicting a value below.
As such, there is considerable uncertainty in the predicted value, hence its overall reliability has been scored as being Low.
The predicted BCF of 465.04 L/kg is below the threshold of a substance being considered as bioaccumulative, i.e. 2000 L/kg. Since the prediction is considered to be of low reliability the result may be used together with results from other QSARs in a weight of evidence.

VEGA
CAESAR from the Vega suite predicted the query compound to possess a BCF value below the threshold for consideration as bioaccumulative, but the result is considered to be of low reliability. The average similarity of the four most similar analogues in the training set to the query structure was shown to be 67% and may be considered moderate. It was shown that the variance between the measured and predicted values for the nearest compounds in the training set as low. Accuracy is therefore considered acceptable. Study values of two of the four the similar structures are in the same region as the predicted result for the query structure, thus indicating moderate concordance. Moderate concordance and moderate similarity with regard to the similar structures suggests some uncertainty, however accuracy was assessed to be acceptable suggesting some confidence in the prediction. However, this confidence is undermined as the prediction has failed to meet the requirements of the applicability domain for the model, with multiple issues identified by the software (lack of similarity, poor accuracy, poor concordance, high error due to experimental variability, and presence of unknown fragments in the target compound). Thus it is concluded that the prediction is of low reliability.
The Meylan model followed in a similar vein, also predicting a BCF value below the threshold, and is also considered of low reliability. Again the average similarity was shown to be moderate with a value of 67%. Good accuracy when considering predicted and actual values for similar structures, and concordance with experimental values. However, as the the CAESAR prediction, the Meylan prediction also fails to meet the requirements of the applicability domain for the model, with the same issues as indicated above. And so again, the prediction was not considered reliable.

Finally, the KNN/Read Across model was unable to return a prediction and so this has not been reported, but has been included in the list of results above, and the model printout has been provided in the Appendices below.

BCF/BAF
The BCF/BAF model from the US EPA’s EPI Suite software predicted the compound to be below the threshold for bioaccumulation, with moderate reliability.
Target compound is within the estimation domain as described in the software for non ionic compounds, with the predicted partition coefficient of 8.30 being within the training set range of -1.37 – 11.26, and the molecular weight being within the range of 68.08 – 959.17)
All fragments of the query compound have been found in the compounds of the training set and in the model respectively. There is some confidence in the prediction as the target compound was within the parameters of the domain expressed within the software. The prediction is for a BCF of 139.5 L/Kg, indicating that the compound should not be considered bioaccumulative. As such the prediction is considered to be moderately reliable.

ToxRead
ToxRead found similar structures with an average similarity of 67.7%, which is considered moderate. The Log BCFs range between 1.15 and 4.02 with an average of 2.815. Uncertainty is indicated as the model was unable to determine a predicted value for the compound, and no alerts were highlighted. Furthermore, due to the variance in results, with two out of four nearest compounds having BCF values above 2000 L/Kg, there is only moderate concordance between these values and the average value of all four compounds.
The average of the four similar compounds can be used as an indicative value however, and suggests a log BCF of 2.815, which would agree with most of the other assessments above, that the predicted BCF may be below the threshold. While not in itself reliable, the result may be used together with results from other QSARs in a weight of evidence.

Discussion
It has been shown that there are significant deficiencies in most of the prediction models used in this assessment when considered individually. The various deficiencies within each are discussed above and in the QPRFs and model printouts below. There is a strong argument to consider the VEGA models as unreliable. However when considered alongside the other models reported upon above and in table 2, it can be seen that these results are within the range of results identified with the other models. Overall there is a range of results established from 139.5 L/Kg, to 653.1 L/Kg, with the most reliable result from BCF/BAF being 465.04 L/Kg. 

In the bioaccumulation study on test substance di-tert-nonyl polysulfide the degree of bioconcentration of the test substance in common carp shown in terms of BCF was ≤0.3 - 1.2 at Level 1 and ≤3.3 at Level 2.

Together these values show that there is a weight of evidence to suggest that the BCF for DAILUBE IS-30 should be below the threshold value for assessment of 2000 L/Kg, and therefore not bioaccumulative.

Conclusion

Weight of evidence of this assessment suggested that DAILUBE IS-30 is not likely to be bioaccumulative with predicted values between 139.5 and 653.1 L/Kg and the BCF study values all ≤3.3 . Though 653.1 L/Kg was not the most reliable value proposed by the assessed models, as a conservative worst case estimate it is proposed that this value should be used for risk assessment.

 

Key value for chemical safety assessment

BCF (aquatic species):

653.1 L/kg ww