Fatty acids, C16-18 and C18-unsatd., compds. with triethanolamine

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

calculation (if not (Q)SAR)

Remarks:

Migrated phrase: estimated by calculation

Adequacy of study:

key study

Study period:

2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Since the substance is a surfactant, the typical experimental procedures cannot be applied. The calculations presented here are outlined in the EU method A.8 (2008).The determinations of the water and octanol solubilities were Klimisch 1 studies.

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Deviations:

no

GLP compliance:

no

Type of method:

other: calculated based on information provided in OECD 107

Partition coefficient type:

octanol-water

Type:

log Pow

Partition coefficient:

>= 4.86

Temp.:

20 °C

pH:

ca. 8.6

Remarks on result:

other: pH is determined in the water solubility study

As laid out in the respective sections of the IUCLID dossier, the water solubility of the registered substance is ca. 10 mg/L the solubility in octanol is > 730 g/L (water solubility and octanol solubility at 20°C). Based on this, the Pow is calculated as >= 73000 and the logPow >= 4.86.

Conclusions:

The logPow is calculated based on the n-octanol solubility and the water solubility to be around 4.86.

Executive summary:

The logPow was determined according to OECD 107 based on the water and n-octanol solubility of the registered substance.

According to the OECD GUIDELINE FOR THE TESTING OF CHEMICALS 107 Adopted by the Council on 27th July 1995: Partition Coefficient (n-octanol/water): Shake Flask Method, paragraph 19 "the results of the preliminary estimation (when the shake flask method is not applicable, e.g. surface active material, a calculated value or an estimate based on the individual n-octanol and water solubilities should be provided)".

 

According to the OECD 107 (paragraph 5) "the partition coefficient (P) is defined as the ratio of the equilibrium concentrations of a dissolved substance in a two-phase system consisting of two largely immiscible solvents. In the case of n-octanol and water:

 

Pow= C octanol/ C water"

with

C octanol: maximum concentration in octanol and C water: maximum concentration in water.

 

"The partition coefficient, being the quotient of two concentrations, or the quotient of the fractions of the test substance in the two phases multiplied by a fixed volume ratio, is dimensionless and is usually given in the form of its logarithm to base ten."

 

As laid out in the respective sections of the IUCLID dossier, the water solubility of the registered substance is 10 mg/L the solubility in octanol is > 730 g/L (water solubility and octanol solubility at 20°C) Based on this, the Pow is calculated as 73000 and the logPow is 4.86.

 

The thus determined log Pow is considered to be acceptable for risk assessment.

Description of key information

The log Kow of the substance is calculated based on the n-octanol solubility and the water solubility to be around 4.86.

Key value for chemical safety assessment

Log Kow (Log Pow):

4.86

at the temperature of:

20 °C

Additional information

Two studies are performed. In the first supporting study the value is obtained by using the HPLC method.

This study is considered as supporting since it is performed for a different batch and it is an older study dating from 2005.

In this study partition coefficient (P) results were defined as the ratio of the equilibrium concentrations of a dissolved substance in a two-phase system of two largely immiscible solvents n-octanol and water. 26 peaks were detected with UV and 8 with RI. The log Pow values ranged from <0.0 to 6.62. These results showed most peaks have log Pow values greater than 3.0, however mean values were 4.58 for UV and 4.65 for RI.

 

In the other study which is taken as the key study, the logPow is calculated based on the n-octanol solubility and the water solubility.

The logPow was determined according to OECD 107 based on the water and n-octanol solubility of the registered substance.

According to the OECD GUIDELINE FOR THE TESTING OF CHEMICALS 107 Adopted by the Council on 27^thJuly 1995: Partition Coefficient (n-octanol/water): Shake Flask Method, paragraph 19 "the results of the preliminary estimation (when the shake flask method is not applicable, e.g. surface active material, a calculated value or an estimate based on the individual n-octanol and water solubilities should be provided)".

 

According to the OECD 107 (paragraph 5) "the partition coefficient (P) is defined as the ratio of the equilibrium concentrations of a dissolved substance in a two-phase system consisting of two largely immiscible solvents. In the case of n-octanol and water:

Pow= C octanol/ C water"

with

C octanol: maximum concentration in octanol and C water: maximum concentration in water.

 

"The partition coefficient, being the quotient of two concentrations, or the quotient of the fractions of the test substance in the two phases multiplied by a fixed volume ratio, is dimensionless and is usually given in the form of its logarithm to base ten."

Based on this, the Pow is calculated as 73000 and the logPow is 4.86.