Benzenemethanamine, 2-chloro-N,N-dimethyl-

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7550 (Partition Coefficient, n-octanol / H2O, Shake Flask Method)

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

Pow

Partition coefficient:

487

Temp.:

23 °C

pH:

10

Type:

log Pow

Partition coefficient:

2.7

Temp.:

23 °C

pH:

10

Details on results:

According to the guideline OECD 107, partition coefficient should be measured of the substance "in their non-ionized form produced by the the use of an appropiate buffer with a pH of at least one unit ... above... the pK." As the pKa of the test substance is 8.4, the substance is non-ionized at pH10 and therefore the measurement at this pH are taken as key value.
The results show that the partition coefficient of the test item is pH dependent, as Kow and logKow at pH7 are 8.8 and 0.9, respectively.

Conclusions:

For the test substance, a logKow of 2.7 was determined at pH10 and 23 °C.

Executive summary:

The partition coefficients 1-octanol / water of the test substacne at room temperature (mean 23°C) were determined according to the “shake flask method” described in European Commission Council Regulation (EC) No 440/2008, Annex, Part A, method A.8., OECD Guideline 107 and US EPA Product Properties Test Guideline OCSPP 830.7550.

At pH10 the tests were performed using 3 different phase ratios of 1-octanol / water: Test 1 ( A and B ): Phase ratio = 1 : 2, Test 2 ( A and B ): Phase ratio = 1 : 1, Test 3 ( A and B ): Phase ratio = 2 : 1.

78.73 mg (initial weight) of the test item were dissolved in 50 mL of 1-octanol (saturated with buffer pH 10) by using an ultrasonic bath (5 min). The concentration of the stock solution was determined by HPLC to be 1573 mg/L. 5 mL portions of the stock solution (equivalent to 7.826 mg, 0.00923 mol/L) plus 10 mL of buffer pH 10 (saturated with 1-octanol) were put in each of six flasks. 5 mL of 1-octanol were added to 2 flasks and 15 mL of 1-octanol were added to two other flasks. Each of the six flasks was shaken (2 min) at room temperature (22.4°C). Each of the separated phases was centrifuged (15 min at 3000 rpm).

The pH values of the aqueous phases were measured.

A similar procedure was conducted at pH7. However, according to the guideline OECD 107, partition coefficient should be measured of the substance "in their non-ionized form produced by the the use of an appropiate buffer with a pH of at least one unit ... above... the pK." As the pKa of the test substance is 8.4, the substance is non-ionized at pH10 and therefore the measurement at this pH are taken as key value.

For the test substance, a logKow of 2.7 was determined at pH10 and 23 °C.

Description of key information

The partition coefficients 1-octanol / water of the test substacne at room temperature (mean 23°C) were determined according to the “shake flask method” described in European Commission Council Regulation (EC) No 440/2008, Annex, Part A, method A.8., OECD Guideline 107 and US EPA Product Properties Test Guideline OCSPP 830.7550.

At pH10 the tests were performed using 3 different phase ratios of 1-octanol / water: Test 1 ( A and B ): Phase ratio = 1 : 2, Test 2 ( A and B ): Phase ratio = 1 : 1, Test 3 ( A and B ): Phase ratio = 2 : 1.

78.73 mg (initial weight) of the test item were dissolved in 50 mL of 1-octanol (saturated with buffer pH 10) by using an ultrasonic bath (5 min). The concentration of the stock solution was determined by HPLC to be 1573 mg/L. 5 mL portions of the stock solution (equivalent to 7.826 mg, 0.00923 mol/L) plus 10 mL of buffer pH 10 (saturated with 1-octanol) were put in each of six flasks. 5 mL of 1-octanol were added to 2 flasks and 15 mL of 1-octanol were added to two other flasks. Each of the six flasks was shaken (2 min) at room temperature (22.4°C). Each of the separated phases was centrifuged (15 min at 3000 rpm).

The pH values of the aqueous phases were measured.

A similar procedure was conducted at pH7. However, according to the guideline OECD 107, partition coefficient should be measured of the substance "in their non-ionized form produced by the the use of an appropiate buffer with a pH of at least one unit ... above... the pK." As the pKa of the test substance is 8.4, the substance is non-ionized at pH10 and therefore the measurement at this pH are taken as key value.

For the test substance, a logKow of 2.7 was determined at pH10 and 23 °C.

Key value for chemical safety assessment

Log Kow (Log Pow):

2.7

at the temperature of:

23 °C