5H-1,2-oxathiole 2,2-dioxide

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

(Q)SAR

Adequacy of study:

key study

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. SOFTWARE
QSAR Toolbox 2.3.0.1132
2. MODEL (incl. version number)
KOCWIN(EPISUITE) Version 2.00
3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
O=S1(=O)OCC=C1
4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
[[Explain how the model fulfils the OECD principles for (Q)SAR model validation. Consider attaching the QMRF and/or QPRF or providing a link]
- Defined endpoint:
Environmental Fate and Transport#Transport and Distribution Between Environmental Compartments#Adsorption/desorption
- Unambiguous algorithm:
Multiple-linear regression’s equation is:
log Koc = 0.55313 Log Kow + 0.9251 + ΣPfN
(n = 447, r2 = 0.855, std dev = 0.396, avg dev = 0.307)
where ΣPfN is the summation of the products of all applicable correction factor coefficients multiplied by the number of times (N) that factor is counted for the structure.

Appendix D Log Kow Correction Factors for 447 Compound Training Set:
Correction Factor Descriptor Coefficient Occurrence(max per structure)
Ketone (-C-CO-C-) 0.1956 1
Aliphatic Alcohol (-C-OH) -0.4114 1
Ether, aliphatic (-C-O-C-) -0.0906 2

- Defined domain of applicability:
Currently there is no universally accepted definition of model domain. However, users may wish to consider the possibility that log Koc estimates are less accurate for compounds outside the MW range of the training set compounds, and/or that have more instances of a given fragment than the maximum for all training set compounds. It is also possible that a compound may have a functional group(s) or other structural features not represented in the training set, and for which no fragment coefficient or correction factor was developed. These points should be taken into consideration when interpreting model results.
The minimum and maximum values for molecular weight are the following:
Training Set Molecular Weights:
Minimum MW: 32.04
Maximum MW: 665.02
Average MW: 224.4

Validation Molecular Weights:
Minimum MW: 73.14
Maximum MW: 504.12
Average MW: 277.8

Appendix D Log Kow Correction Factors for 447 Compound Training Set:
Correction Factor Descriptor Coefficient Occurrence(max per structure)
Ketone (-C-CO-C-) 0.1956 1
Aliphatic Alcohol (-C-OH) -0.4114 1
Ether, aliphatic (-C-O-C-) -0.0906 2

- Appropriate measures of goodness-of-fit and robustness and predictivity:
yes
- Mechanistic interpretation:
Soil sorption is closely related to water solubility and hydrophobicity (logPow). Therefore, the chemical features which determine the soil sorption are similar to the ones which determine water solubility.

5. APPLICABILITY DOMAIN
[Explain how the substance falls within the applicability domain of the model]
- Descriptor domain:
LogKow is only descriptor in the model. No further requirements for logKow are required.
- Structural and mechanistic domains:
The above mentioned fragment Ketone (-C-CO-C-), Aliphatic Alcohol (-C-OH) and Ether, aromatic (-C-O-C-) are in the training set and validation set.The substance is considered to be in the same mechanism domain as molecules in the training set.



6. ADEQUACY OF THE RESULT
[Explain how the prediction fits the purpose of classification and labelling and/or risk assessment]
The number of the fragment Ketone (-C-CO-C-), Aliphatic Alcohol (-C-OH) and Ether, aromatic (-C-O-C-) in the substance is 1, 1, 1 individually, which are within the maximum number of 1, 1, 2 for all training set compounds. The molecular weight of the substance is 126.11, within the scope of the model (32.04~665.02).Therefore, the predicted value is considered to be reliable.

Guideline:

other: REACH guideline on QSARs R.6

Principles of method if other than guideline:

General model

Key result

Type:

Koc

Value:

9.411 L/kg

Temp.:

25 °C

Remarks on result:

other: pH is not available

Currently there is no universally accepted definition of model domain. However, users may wish to consider the possibility that log Koc estimates are less accurate for compounds outside the MW range of the training set compounds, and/or that have more instances of a given fragment than the maximum for all training set compounds. It is also possible that a compound may have a functional group(s) or other structural features not represented in the training set, and for which no fragment coefficient or correction factor was developed. These points should be taken into consideration when interpreting model results.

The minimum and maximum values for molecular weight are the following:

Training Set Molecular Weights:

Minimum MW: 32.04

Maximum MW: 665.02

Average MW: 224.4

 

Validation Molecular Weights:

Minimum MW: 73.14

Maximum MW: 504.12

Average MW: 277.8

 

Appendix D Log Kow Correction Factors for 447 Compound Training Set:

Correction Factor Descriptor                Coefficient        Occurrence(max per structure)

Ketone (-C-CO-C-)                          0.1956                 1

Aliphatic Alcohol (-C-OH)                    -0.4114                1

Ether, aliphatic (-C-O-C-)                    -0.0906                2

Conclusions:

The substance is predicted to have Koc of 9.411 L/Kg.

Description of key information

The substance is predicted to have Koc of 9.411 L/Kg.

Key value for chemical safety assessment

Koc at 20 °C:

9.411