isostearic acid monoisopropanolamide

Vapour pressure

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From May 31, 1999 to July 01, 1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

gas saturation method

Key result

Temp.:

ca. 25 °C

Vapour pressure:

ca. 0 Pa

Remarks on result:

other: first component (mass 314)

Key result

Temp.:

ca. 25 °C

Vapour pressure:

ca. 0 Pa

Remarks on result:

other: second component (mass 342)

Key result

Temp.:

ca. 70 °C

Vapour pressure:

ca. 0 Pa

Remarks on result:

other: first component (mass 314)

Key result

Temp.:

ca. 70 °C

Vapour pressure:

ca. 0 Pa

Remarks on result:

other: second component (mass 342)

Key result

Temp.:

ca. 80 °C

Vapour pressure:

ca. 0.001 Pa

Remarks on result:

other: first component (mass 314)

Temp.:

80 °C

Vapour pressure:

0 Pa

Remarks on result:

other: second component (mass 342)

The vapour pressure of the test substance was measured at 70°C and 80°C. The vapour pressure at 25°C was extrapolated (by linear regression) from the measured values. The chromatography of the test substance resulted in several main peaks. This was caused by the test substance, which is a mixture of different isomeric compounds and impurities. Therefore, LCMS analysis was used for quantification and two components with a mass of 342 and 314 were used as representative peaks. Their concentrations were extrapolated from the calibration curve.

Table 1. Values for the two compounds

Temperature (°C)	First component (mass 314) (Pa)	Second component (mass 342) (Pa)
70	3.45E-04	1.67E-04
80	1.03E-03	2.19E-04
25	1.02E-06	4.13E-05

Conclusions:

Under the study conditions, the vapour pressure was determined to be 4.13E-5 Pa at 25°C.

Executive summary:

A study was conducted to determine the vapour pressure of the test substance, IsoC18 MIPA (94.1% active), according to OECD Guideline 104 and EU Method A.4, in compliance with GLP. Under the study conditions, the vapour pressure was determined to be 4.13E-5 Pa at 25°C (Tognucci, 1999).

Reference 2

Endpoint:

vapour pressure

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, but not (completely) falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

QSAR prediction from a well-known and acknowledged tool. See below under ''attached background material section' for QPRF containing methodology and domain evaluation details.

Qualifier:

according to guideline

Guideline:

other: REACH guidance on QSARs: Chapter R.6. QSARs and grouping of chemicals

Principles of method if other than guideline:

The vapour pressure (VP) value for the test substance were estimated using the Modified Grain method of the MPBPWIN v1.44 program in EPI SuiteTM v4.11. Since the test substance is a UVCB, the VP values were predicted for the individual constituents using SMILES codes as the input parameter.

Type of method:

other: Modified Grain method (using the MPBPWIN v1.44 program in EPI SuiteTM v4.11)

Key result

Temp.:

25 °C

Vapour pressure:

0 Pa

Remarks on result:

other: predicted for the main constituents (indicating low vapour pressure or volatility)

Key result

Temp.:

25 °C

Vapour pressure:

0 Pa

Remarks on result:

other: weighted average vapour pressure (indicating low vapour pressure or volatility)

Predicted value (model result):

The estimated VP values for the remaining constituents using the modified grain method were as follows:

Table 1: Vapour pressure predictions: Modified Grain Method

Constituents/Carbon chain length*	Mean/adjusted conc	Mole fraction Xi = (mi/Mi)/∑ (mi/Mi)	VP	VP * xi	Domain evaluation
Branched	95	1	2.34E-07	2.34E-07	MW, MP (ID), BP, VP (OD), structural fragment (ID)
			VP=	2.34E-07

*Glycerol or MIPA residues have not been considered for QSAR predictions

 

Table 2: Modified vapour pressure predictions: Modified Grain Method

Constituents/Carbon chain length*	Mean/adjusted conc	Mole fraction Xi = (mi/Mi)/∑ (mi/Mi)	VP	VP * xi	Domain evaluation
Branched	95	1	1.34E-04**	1.34E-04	MW, MP (ID), BP, VP (OD), structural fragment (ID)
			VP=	0.000134

*Glycerol or MIPA residues have not been considered for QSAR predictions

** Since the predicted VP values are lower than the cut-off VP value, below which the chances of introduction of error increases, the VP values are simplified and presented as less than the cut-off, instead of the individual predictions.

 

Vapour pressure prediction result:

 

Experimental Database Structure Match: no data

 

SMILES : O=C(NCC(O)C)CCCCCCCCCCCCCCC(C)C

CHEM  : Branched

MOL FOR: C21 H43 N1 O2

MOL WT : 341.58

------------------------ SUMMARY MPBPWIN v1.44 --------------------

 

 

Boiling Point: 467.97 deg C (Adapted Stein and Brown Method)

 

Melting Point: 297.82 deg C (Adapted Joback Method)

Melting Point: 159.59 deg C (Gold and Ogle Method)

Mean Melt Pt : 228.70 deg C (Joback; Gold,Ogle Methods)

 Selected MP: 187.23 deg C (Weighted Value)

 

Vapor Pressure Estimations (25 deg C):

 (Using BP: 467.97 deg C (estimated))

 (Using MP: 187.23 deg C (estimated))

   VP: 7.64E-013 mm Hg (Antoine Method)

     : 1.02E-010 Pa (Antoine Method)

   VP: 3.52E-011 mm Hg (Modified Grain Method)

     : 4.7E-009 Pa (Modified Grain Method)

   VP: 9.19E-009 mm Hg (Mackay Method)

     : 1.23E-006 Pa (Mackay Method)

 Selected VP: 3.52E-011 mm Hg (Modified Grain Method)

            : 4.7E-009 Pa (Modified Grain Method)

 Subcooled liquid VP: 1.75E-009 mm Hg (25 deg C, Mod-Grain method)

                    : 2.34E-007 Pa (25 deg C, Mod-Grain method)

 

-------+-----+--------------------+----------+---------

 TYPE | NUM | BOIL DESCRIPTION | COEFF  | VALUE 

-------+-----+--------------------+----------+---------

 Group | 3 | -CH3             |  21.98 |  65.94

 Group | 15 | -CH2-            |  24.22 | 363.30

 Group | 2 | >CH-             |  11.86 |  23.72

 Group | 1 | -OH (secondary)  |  80.63 |  80.63

 Group | 1 | -C(=O)NH-        | 225.09 | 225.09

  *  |    | Equation Constant |         | 198.18

=============+====================+==========+=========

RESULT-uncorr| BOILING POINT in deg Kelvin | 956.86

RESULT- corr | BOILING POINT in deg Kelvin | 741.13

            | BOILING POINT in deg C      | 467.97

-------------------------------------------------------

 

-------+-----+--------------------+----------+---------

 TYPE | NUM | MELT DESCRIPTION | COEFF  | VALUE 

-------+-----+--------------------+----------+---------

 Group | 3 | -CH3             |  -5.10 | -15.30

 Group | 15 | -CH2-            |  11.27 | 169.05

 Group | 2 | >CH-             |  12.64 |  25.28

 Group | 1 | -OH (secondary)  |  44.45 |  44.45

 Group | 1 | -C(=O)NH-        | 225.00 | 225.00

  *  |    | Equation Constant |         | 122.50

=============+====================+==========+=========

  RESULT   | MELTING POINT in deg Kelvin | 570.98

            | MELTING POINT in deg C      | 297.82

-------------------------------------------------------

Conclusions:

Using the Modified Grain method, of MPBPWIN v1.44 program of EPI SuiteTM, the weighted average VP value for test substance was predicted to be <1.34E-4 Pa at 25°C.

Executive summary:

The vapour pressure (VP) of the test substance, IsoC18 MIPA, was predicted using the Modified Grain method of the MPBPWIN v1.44 program (EPI SuiteTMv4.11). The test substance is mono constituent, the VP values were predicted using SMILES codes as the input parameter. Using the Modified Grain method, the VP value of the test substance was 2.34E-07 at 25°C (original estimate) (US EPA, 2019). Since the constituent does not meet the boiling point (BP) and VP molecular descriptor domain criteria as defined in the MPBPVP user guide of EPI Suite TM, the VP prediction was considered to be less accurate. However, for the VP parameter the chances of introducing errors when the predicted VP values were below the cut-off set by the tool, was reduced by substituting the individual VP values as less than the cut-off value (i.e., <1.34E-4 Pa). Therefore, the VP value was calculated as <1.34E-4 Pa, indicating the test substance to have a low volatility potential (ECHA, 2017) and low fugacity (ECHA, 2009), leading to low inhalation exposure to users and environmental exposure through air or via volatilization from water. Overall, the VP predictions for the test substance using MPBPVP model of EPI Suite TM can be considered to be reliable with low to moderate confidence.

Reference 3

Endpoint:

vapour pressure

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, but not (completely) falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

QSAR prediction from a well-known and acknowledged tool. See below under ''attached background material section' for QPRF containing methodology and domain evaluation details.

Qualifier:

according to guideline

Guideline:

other: REACH guidance on QSARs: Chapter R.6. QSARs and grouping of chemicals

Principles of method if other than guideline:

The vapour pressure (VP) value for the test substance were estimated using the Consensus method of the US EPA T.E.S.T v.4.2.1. Since the test substance is a UVCB, the VP values were predicted for the individual constituents using SMILES codes as the input parameter.

Key result

Temp.:

25 °C

Vapour pressure:

0 Pa

Remarks on result:

other: predicted for the main constituents (indicating low vapour pressure or volatility)

Predicted value (model result):

The estimated VP values for the remaining constituents using the Consensus method were as follows:

Table 1: Vapour pressure predictions: Consensus

Constituents/Carbon chain length*	Mean/adjusted conc.	Mole fraction Xi = (mi/Mi)/∑ (mi/Mi)	Vapour pressure (Pa) TEST	VP x Xi TEST (Pa)
Branched	95	1	2.19E-06	2.19E-06
			VP=	2.19E-06

*Glycerol or DEA residues have not been considered for QSAR predictions

 

Table 2: Domain evaluation

Substance		Model	Applicability Domain			Prediction accuracy
Carbon chain length	Concentration range	TEST Consensus	General	Descriptor	Structural	MAE for chemicals with similarity coefficient ≥ 0.5; Dataset MAE is 0.47	Accuracy
C12	42-65%	Hierarchical clustering	ID	ID	ID	0.64	Low
		Group contribution	ID	ID	ID
		FDA	ID	ID	ID
		Nearest neighbour	ID	MW-OD Log Kow-ID	OD(similarity coefficient: 0.86 - 0.89; structural fragments: OD (missing amide (-N< [aliphatic attach]) group present in target)

MW: molecular weight, log Kow: partition coefficient; VP: Vapour pressure; ID: in domain, OD: out domain

Conclusions:

Using the Consensus method, of T.E.S.T. v4.2.1 program, the weighted average VP value for test substance was predicted to be 2.19E-06 Pa at 25°C.

Executive summary:

The vapour pressure (VP) of the test substance, IsoC18 MIPA, was calculated using the Consensus method of T.E.S.T. v4.2.1 program. Since the test substance is a Mono-constituent, the VP was predicted using SMILES codes as the input parameter. Using the Consensus method, the predicted VP value of the constituent was 2.19E-06 Pa at 25 °C, indicating a low vapour pressure (US EPA, 2019). As the constituents was not within the MW or the structural fragment domain criteria as defined in the T.E.S.T. user guide of EPA, the VP prediction was considered to be less accurate. Therefore, considering the VP predictions for the constituent, the test substance is expected to have a low volatility potential (ECHA, 2017) and low fugacity (ECHA, 2009), leading to low inhalation exposure to users and environmental exposure through air or via volatilization from water. Further, based on the mean absolute error (MAE) criteria, the prediction accuracy was considered to be moderate. Therefore, the VP predictions for the test substance using T.E.S.T. model overall can be considered to be of reliable with low to moderate confidence.

Description of key information

The vapour pressure was determined according to OECD Guideline 104 and EU Method A.4 (gas saturation method) (Tognucci, 1999). Weighted average vapour pressure values for the test substance were also modelled using the Modified Grain method of the MPBPWIN v1.44 program of EPI Suite and the Consensus method of the T.E.S.T. v4.2.1 program.

Key value for chemical safety assessment

Vapour pressure:

0 Pa

at the temperature of:

25 °C

Additional information

Using the Modified Grain method of the MPBPWIN v1.44 program of EPI Suite, the weighted average vapour pressure for the test substance was predicted to be <1.34E-4 Pa at 25°C. According to the Consensus method of the T.E.S.T. v4.2.1 program, the weighted average vapour pressure was 2.19E-06 Pa at 25°C.