Decanoic acid, mixed esters with heptanoic acid, octanoic acid and trimethylolpropane

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

February 2014

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The substance is a UVCB. Standard tests for partition coefficient are intended for single substances and are not appropriate for this complex substance. It is unlikely that a study result would give anything other than a “greater than” limit value of the highest value available in the tests available, which allow for the following ranges: Shake Flask Method: log POW between -2 and 4 HPLC method: log POW between 0 and 6 Slow-Stirring Method: 5 to 8 Conducting one of these tests is likely to give a limit value. On this basis, a QSAR value was determined to be a more appropriate assessment for this substance. An appropriate QPRF is attached below.

Qualifier:

no guideline followed

Principles of method if other than guideline:

KOWWIN (the Log Octanol-Water Partition Coefficient Program) estimates the logarithmic octanol-water partition coefficient (log P) of organic compounds. KOWWIN requires only a chemical structure to estimate a log P. Structures are entered into KOWWIN by SMILES (Simplified Molecular Input Line Entry System) notations.

The KOWWIN program and estimation methodology were developed at Syracuse Research Corporation.

KOWWIN uses a "fragment constant" methodology to predict log P. In a "fragment constant" method, a structure is divided into fragments (atom or larger functional groups) and coefficient values of each fragment or group are summed together to yield the log P estimate. KOWWIN’s methodology is known as an Atom/Fragment Contribution (AFC) method. Coefficients for individual fragments and groups were derived by multiple regression of 2447 reliably measured log P values. KOWWIN’s "reductionist" fragment constant methodology (i.e. derivation via multiple regression) differs from the "constructionist" fragment constant methodology of Hansch and Leo (1979) that is available in the CLOGP Program (Daylight, 1995). See the Meylan and Howard (1995) journal article for a more complete description of KOWWIN’s methodology.

The KOWWIN training and validation datasets can be downloaded from the Internet at:
http://esc.syrres.com/interkow/KowwinData.htm

References:
Hansch, C and Leo, A.J. 1979. Substituent Constants for Correlation Analysis in Chemistry and Biology; Wiley: New York, 1979.
Daylight. 1995. CLOGP Program. Daylight Chemical Information Systems. Von Karman Ave., Irvine, CA 92715. (web-site as of March 2008: http://www.daylight.com/)
Meylan, W.M. and P.H. Howard. 1995. Atom/fragment contribution method for estimating octanol-water partition coefficients. J. Pharm. Sci. 84: 83-92.

GLP compliance:

no

Type of method:

other: QSAR

Partition coefficient type:

octanol-water

Analytical method:

other: Not required - QSAR calculation

Key result

Type:

log Pow

Partition coefficient:

9.66

Temp.:

25 °C

Remarks on result:

other: trimethylolpropane tri-ester with 2xC7 acids, 1xC8 acids; MW 484; pH not considered in calculation

Key result

Type:

log Pow

Partition coefficient:

10.15

Temp.:

25 °C

Remarks on result:

other: trimethylolpropane tri-ester with 1xC7 acids, 2xC8 acids; MW 498; pH not considered in calculation

Key result

Type:

log Pow

Partition coefficient:

10.64

Temp.:

25 °C

Remarks on result:

other: trimethylolpropane tri-ester with 2xC7 acids, 1xC10 acids or 3xC7 acids; MW 512; pH not considered in calculation

Key result

Type:

log Pow

Partition coefficient:

11.13

Temp.:

25 °C

Remarks on result:

other: trimethylolpropane tri-ester with 1xC7 acids, 1xC8 acids and 1xC10 acids; MW 526; pH not considered in calculation

Type:

log Pow

Partition coefficient:

11.62

Temp.:

25 °C

Remarks on result:

other: trimethylolpropane tri-ester with 2xC7 acids, 1xC10 acids; MW 540; pH not considered in calculation

Details on results:

the log Pow was calculated for the most relevant constituents of this UVCB with area % > 10% in the GC-FID chromatogram (see also sections 1.2 and 8)

1. log Pow calculation for component MW 484, present for ca 12.4% (w/w) in Hatcol 1510:

SMILES : CCCCCCC(=O)OCC(CC)(COC(=O)CCCCCC)COC(=O)CCCCCCC

CHEM  : TMP tri-ester, 2xC7 acids, 1xC8 acids

MOL FOR: C28 H52 O6

MOL WT : 484.72

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

 TYPE | NUM |       LOGKOW FRAGMENT DESCRIPTION        | COEFF | VALUE

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

 Frag | 4 | -CH3   [aliphatic carbon]               | 0.5473 | 2.1892

 Frag | 20 | -CH2-  [aliphatic carbon]               | 0.4911 | 9.8220

 Frag | 3 | -C(=O)O [ester, aliphatic attach]       |-0.9505 | -2.8515

 Frag | 1 | -tert Carbon [3 or more carbon attach]  | 0.2676 | 0.2676

 Const |    | Equation Constant                        |        | 0.2290

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

                                                        Log Kow  =  9.6563

2. log Pow calculation for component MW 498, present for ca 14.9% (w/w) in Hatcol 1510:

SMILES : CCCCCCCC(=O)OCC(CC)(COC(=O)CCCCCCC)COC(=O)CCCCCC

CHEM  : TMP tri-ester, 1xC7 acids, 2xC8 acids

MOL FOR: C29 H54 O6

MOL WT : 498.75

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

 TYPE | NUM |       LOGKOW FRAGMENT DESCRIPTION        | COEFF | VALUE

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

 Frag | 4 | -CH3   [aliphatic carbon]               | 0.5473 | 2.1892

 Frag | 21 | -CH2-  [aliphatic carbon]               | 0.4911 | 10.3131

 Frag | 3 | -C(=O)O [ester, aliphatic attach]       |-0.9505 | -2.8515

 Frag | 1 | -tert Carbon [3 or more carbon attach]  | 0.2676 | 0.2676

 Const |    | Equation Constant                        |        | 0.2290

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

                                                        Log Kow  = 10.1474

3. log Pow calculation for component MW 512, present for ca 15% (w/w) in Hatcol 1510:

SMILES : CCCCCCCC(=O)OCC(CC)(COC(=O)CCCCCCC)COC(=O)CCCCCCC

CHEM  : C7 -tri-ester

SMILES : CCCCCCC(=O)OCC(CC)(COC(=O)CCCCCCCCC)COC(=O)CCCCCC

CHEM  : TMP tri-ester, 2xC7 acids, 1xC10 acids

MOL FOR: C30 H56 O6

MOL WT : 512.78

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

 TYPE | NUM |       LOGKOW FRAGMENT DESCRIPTION        | COEFF | VALUE

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

 Frag | 4 | -CH3   [aliphatic carbon]               | 0.5473 | 2.1892

 Frag | 22 | -CH2-  [aliphatic carbon]               | 0.4911 | 10.8042

 Frag | 3 | -C(=O)O [ester, aliphatic attach]       |-0.9505 | -2.8515

 Frag | 1 | -tert Carbon [3 or more carbon attach]  | 0.2676 | 0.2676

 Const |    | Equation Constant                        |        | 0.2290

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

                                                        Log Kow  = 10.6385

4. log Pow calculation for component MW 526, present for ca 20.4% (w/w) in Hatcol 1510:

SMILES : CCCCCCCCCC(=O)OCC(CC)(COC(=O)CCCCCC)COC(=O)CCCCCCC

CHEM  : TMP tri-ester, 1xC7 acids, 1xC8 acids, 1xC10 acids

MOL FOR: C31 H58 O6

MOL WT : 526.80

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

 TYPE | NUM |       LOGKOW FRAGMENT DESCRIPTION        | COEFF | VALUE

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

 Frag | 4 | -CH3   [aliphatic carbon]               | 0.5473 | 2.1892

 Frag | 23 | -CH2-  [aliphatic carbon]               | 0.4911 | 11.2953

 Frag | 3 | -C(=O)O [ester, aliphatic attach]       |-0.9505 | -2.8515

 Frag | 1 | -tert Carbon [3 or more carbon attach]  | 0.2676 | 0.2676

 Const |    | Equation Constant                        |        | 0.2290

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

                                                        Log Kow  = 11.1296

5. log Pow calculation for component MW 540, present for ca 12.9% (w/w) in Hatcol 1510:

SMILES : CCCCCCCC(=O)OCC(CC)(COC(=O)CCCCCCCCC)COC(=O)CCCCCCC

CHEM  : TMP tri-ester, 2xC8 acids, 1xC10 acids

MOL FOR: C32 H60 O6

MOL WT : 540.83

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

 TYPE | NUM |       LOGKOW FRAGMENT DESCRIPTION        | COEFF | VALUE

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

 Frag | 4 | -CH3   [aliphatic carbon]               | 0.5473 | 2.1892

 Frag | 24 | -CH2-  [aliphatic carbon]               | 0.4911 | 11.7864

 Frag | 3 | -C(=O)O [ester, aliphatic attach]       |-0.9505 | -2.8515

 Frag | 1 | -tert Carbon [3 or more carbon attach]  | 0.2676 | 0.2676

 Const |    | Equation Constant                        |        | 0.2290

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

                                                        Log Kow  = 11.6207

Conclusions:

Based on structural features, the log Pow of the components of Hatcol 1510 which are present for more than 10% (w/w) were calculated to be 9.66, 10.15, 10.64, 11.13 and 11.62 using EPISuite 4.11 (estimation with KOWWIN Program (v1.68)). Whilst the high values indicate that the substance in theory could have the potential to bioaccumulate, however the high log Pow is considered to be more a consequence of poor water solubility than a lipophilic tendency and is considered to be not indicative of the tendency to bioaccumulate in lipid tissues of aquatic organisms. This is based in part on an evaluation of literature data which demonstrates a tendency for the Bioconcentration Factor (BCF) to decrease as Log Pow increases above 6. 

Description of key information

The log Kow values for the components present at more than 10% (w/w) were estimated using the KOWWIN Program (v1.68).

Key value for chemical safety assessment

Log Kow (Log Pow):

9.66

at the temperature of:

20 °C

Additional information

In order to give an indication of the possible log K_owof the test substance, this property was calculated for the most abundant esters present in the substance (> 10% w/w). The log Kowvalues were estimated using the KOWWIN Program (v1.68). Based on structural features, the log Kow values for the 5 components of the test substance present at more than 10% (w/w) were calculated to be 9.66, 10.15, 10.64, 11.13 and 11.62.

Whilst the high values indicate that the substance in theory could have the potential to bioaccumulate, however the high log Pow is considered to be more a consequence of poor water solubility than a lipophilic tendency and is considered to be not indicative of the tendency to bioaccumulate in lipid tissues of aquatic organisms. This is based in part on an evaluation of literature data which demonstrates a tendency for the Bioconcentration Factor (BCF) to decrease as Log Pow increases above 6.