Reaction mass of 1,1'-(2,2,4-trimethylhexane-1,6-diyl)bis-1H-pyrrole-2,5-dione and 1H-Pyrrole-2,5-dione, 1,1'-(2,4,4-trimethyl-1,6-hexanediyl)bis-

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

(Q)SAR

Adequacy of study:

supporting 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
EPI Suite v4.10 Estimation Programs Interface Suite™ for Microsoft® Windows v 4.10. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

2. MODEL (incl. version number)
KOCWIN v2.00

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
O=C(C=C1)N(CC(C)CC(C)(C)CCN2C(=O)(C=CC2(=O)))C1(=O)

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See attached information on the model provided by the developer. Further information on the OECD criteria as outlined by the applicant is provided below under "Any other information of materials and methods incl. tables"

5. APPLICABILITY DOMAIN
See attached information and information as provided in "Overall remarks, attachments" section.

6. ADEQUACY OF THE RESULT
See assessment of adequacy as outlined in the "Overall remarks, attachments" section.

Qualifier:

according to guideline

Guideline:

other: REACH Guidance on QSARs R.6

Principles of method if other than guideline:

- Software tool(s) used including version: EPI Suite v4.10
- Model(s) used: KOCWIN v2.00
- Model description: see field 'Justification for non-standard information', 'Attached justification' and 'any other information on Material and methods'
- Justification of QSAR prediction: see field 'Justification for type of information', 'Attached justification' and/or 'overall remarks'

GLP compliance:

no

Details on test conditions:

BASIS FOR CALCULATION OF Koc:
- Estimation software: EPI Suite™ v4.10, KOCWIN v2.00, Log Kow based method

Type:

Koc

Value:

382.9 L/kg

Temp.:

25 °C

Remarks on result:

other: Koc Estimate from Log Pow

Type:

log Koc

Value:

2.583 dimensionless

Temp.:

25 °C

Remarks on result:

other: Koc Estimate from Log Pow

Type:

Koc

Value:

4 935 L/kg

Temp.:

25 °C

Remarks on result:

other: Koc Estimate from MCI

Type:

log Koc

Value:

3.69 dimensionless

Temp.:

25 °C

Remarks on result:

other: Koc Estimate from MCI

Table 1: Koc Estimate based on MCI method

Endpoint (OECD Principle 1)	Endpoint		Adsorption   Adsorption coefficient normalized for organic carbon (Koc)
Algorithm (OECD Principle 2)	Model / submodel name		Model: KOCWIN v2.00 Submodel: MCI (molecular connectivity index)
	Predicted value (model result)		See “Results and discussion”
	Input for prediction:		See: “Test material identity”
	Descriptor values:		No specific descriptor values used. Input parameter only smiles code
Applicability domain (OECD principle 3)	Descriptor domain
	Descriptor		Training set		Substance specific data		Applicability domain fulfilled yes/no
	a) Molecular weight (g/mol)		32.04 – 665.02 / 73.14 – 504.12		318.38		yes
	b) Log Kow		-2.11 – 8.12 / 5.98 – 8.68		3.09		yes
	Structural domain
	Fragment		Maximum number of instances in the training set)		Substance specific data		Applicability domain fulfilled yes/no
	Nitrogen to Carbon (aliphatic) (-N-C)		2		2		yes
	Carbamate (N-CO-O) or (N-CO-S)		2		0		yes
	Ester (-C-CO-O-C-) or (HCO-O-C)		2		0		yes
	Additional characteristics specified by model developer
The uncertainty of the prediction (OECD principle 4)	see “Any other information on materials and methods incl. tables”
The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5).	see “Any other information on materials and methods incl. tables”
Model performance on similar substances **
Name and/or CAS No.	SMILES	Experimental log Koc		Predicted log Koc		Quality of prediction*
123-33-1	O=C1NNC(=O)C=C1	0.45		0.5189		good
5902-51-2	CC1NC(=O)N(C(=O)C=1Cl )C(C)(C)C	1.66		1.6999		good
80045-52-9	CC(C)c1ccc(cc1)C(=O)NC( C)(C)C#C	2.17		2.8768		moderate

There is no universally accepted definition of model domain.  However, MATMD has a MW in the MW range of the training set compounds. Nitrogen-carbonyl and nitrogen-carbon fragments have been considered. General review of Koc approach is given in Doucette (2000, 2003).

 

Conclusions on the adequacy of results

Single substance constituents do not completely fit into the applicability domain of the model. However, the calculated values can be used as an indication of a low adsorption potential and it is considered adequate for the regulatory purpose under REACh regulation (EC) No 1907/2006.

Table 1: Koc Estimate based on log Kow

Endpoint (OECD Principle 1)	Endpoint		Adsorption   Adsorption coefficient normalized for organic carbon (Koc)
Algorithm (OECD Principle 2)	Model / submodel name		Model: KOCWIN v2.00 Submodel: Estimation Using Log Kow
	Predicted value (model result)		See “Results and discussion”
	Input for prediction:		See: “Test material identity”
	Descriptor values:		No specific descriptor values used. Input parameter only smiles code
Applicability domain (OECD principle 3)	Descriptor domain
	Descriptor		Training set		Substance specific data		Applicability domain fulfilled yes/no
	a) Molecular weight (g/mol)		32.04 – 665.02		318.38		yes
	b) Log Kow		-2.11 – 8.12		3.09		yes
	Structural domain
	Fragment		Maximum number of instances in the training set)		Substance specific data		Applicability domain fulfilled yes/no
	Nitrogen to Carbon (aliphatic) (-N-C)		2		2		yes
	Carbamate (N-CO-O) or (N-CO-S)		2		0		yes
	Ester (-C-CO-O-C-) or (HCO-O-C)		2		0		yes
	Additional characteristics specified by model developer
The uncertainty of the prediction (OECD principle 4)	see “Any other information on materials and methods incl. tables”
The chemical and biological mechanisms according to the model underpinning the predicted result (OECD principle 5).	see “Any other information on materials and methods incl. tables”
Model performance on similar substances **
Name and/or CAS No.	SMILES	Experimental log Koc		Predicted log Koc		Quality of prediction*
123-33-1	O=C1NNC(=O)C=C1	0.45		0.4529		good
5902-51-2	CC1NC(=O)N(C(=O)C=1Cl )C(C)(C)C	1.66		1.9576		good
80045-52-9	CC(C)c1ccc(cc1)C(=O)NC( C)(C)C#C	2.17		2.7427		moderate

 

There is no universally accepted definition of model domain.  However, MATMD has a MW in the MW range of the training set compounds. Nitrogen-carbonyl and nitrogen-carbon fragments have been considered. General review of Koc approach is given in Doucette (2000, 2003).

 

Conclusions on the adequacy of results

Single substance constituents do not completely fit into the applicability domain of the model. However, the calculated values can be used as an indication of a low adsorption potential and it is considered adequate for the regulatory purpose under REACh regulation (EC) No 1907/2006.

Validity criteria fulfilled:

yes

Conclusions:

The Koc of both components, estimated based on the log Pow, is 382.9 L/kg (log Koc: 2.58). A Koc of 4935 L/kg (log Koc 3.69) was estimated for both components by the MCI method.

Description of key information

The adsorption potential of the substance is low (log Koc: 2.58).

Key value for chemical safety assessment

Koc at 20 °C:

2.58

Additional information

The adsorption potential of the substance is expected to be low based on the experimentally determined log Pow of 2.38 of the main substance component at neutral pH. QSAR estimations performed with KOCWIN v2.00 for the main substance components estimated log Koc values of 2.58 (based on log Kow) and 3.69 (MCI) respectively.