Trixylyl phosphate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

September 10 2010 to September 11 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP, carried out according to recognised guideline

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

> 6.2

Remarks on result:

other: estimated

Key result

Type:

log Pow

Partition coefficient:

6.38

Remarks on result:

other: extrapolated

Details on results:

The three calibration series and three test item series were measured alternately. The partition coefficient pow was determined based on a calibration curve using 8 reference substances.
The capacity factors k’ were calculated from the dead time and retention times of the reference substances. The log k’ data of the reference substances were plotted against their log pow values. The resulting calibration curve and the respective data are given in Figure 1(attached) and Table 1 (below), respectively.
Quality criteria were met, as values of log p derived from individual measurements fell within a range of =+/- 0.1 log units.
Retention time measured for Kronitex TXP (9.72 min) is higher than that of the last eluting standard; DDT (8.90 min).This result shows that log Pow of Kronitex TXP is higher than the calibrated range. Therefore an extrapolated value was determined in line with guidelines OECD 117 and EU method A.8.

The estimated log Pow is higher than 6.2.
The extrapolated log Pow value of Kronitex TXP is 6.38.

Table 1.:     Measured and calculated data of the reference substances:

Chemical name	log pow	Retention time (min)	log k	Repeatability Dlog pow log unit	Accuracy log unit	log pow
	OECD 117		Calculated			Calculated
Thiourea	-	2.64	for determination of dead time
		2.62
		2.62
		2.62
		2.62
		2.62
	Mean	2.62
	CV%	0.3
Methyl Benzoate	2.1	3.50	-0.476	0.05	0.04	2.1
		3.51	-0.471			2.2
		3.49	-0.481			2.1
		3.49	-0.481			2.1
		3.50	-0.476			2.1
		3.50	-0.476			2.1
	Mean	3.50	-0.477			2.1
	CV%	0.2	-			-
Ethyl Benzoate	2.6	3.82	-0.341	0.02	0.18	2.8
		3.82	-0.341			2.8
		3.83	-0.337			2.8
		3.82	-0.341			2.8
		3.83	-0.337			2.8
		3.83	-0.337			2.8
	Mean	3.83	-0.339			2.8
	CV%	0.1	-			-
Benzophenone	3.2	3.88	-0.320	0.03	0.31	2.9
		3.88	-0.320			2.9
		3.89	-0.316			2.9
		3.89	-0.316			2.9
		3.90	-0.313			2.9
		3.89	-0.316			2.9
	Mean	3.89	-0.317			2.9
	CV%	0.2	-			-
Diphenylamine	3.4	4.05	-0.265	0.06	0.24	3.1
		4.06	-0.261			3.1
		4.07	-0.258			3.2
		4.07	-0.258			3.2
		4.09	-0.253			3.2
		4.08	-0.255			3.2
	Mean	4.07	-0.259			3.2
	CV%	0.3	-			-

Table 1.:     Measured and calculated data of the reference substances (continued):

Chemical name	log pow	Retention time (min)	log k	Repeatability Dlog pow log unit	Accuracy log unit	log pow
	OECD 117		Calculated			Calculated
Naphthalene	3.6	4.53	-0.139	0.03	0.13	3.7
		4.52	-0.141			3.7
		4.55	-0.134			3.7
		4.55	-0.134			3.7
		4.55	-0.134			3.7
		4.55	-0.134			3.7
	Mean	4.54	-0.136			3.7
	CV%	0.3	-			-
Phenanthrene	4.5	5.75	0.076	0.04	0.25	4.7
		5.76	0.078			4.7
		5.80	0.083			4.8
		5.79	0.082			4.7
		5.81	0.084			4.8
		5.81	0.084			4.8
	Mean	5.79	0.081			4.7
	CV%	0.4	-			-
Triphenylamine	5.7	7.67	0.284	0.04	0.01	5.7
		7.67	0.284			5.7
		7.73	0.289			5.7
		7.73	0.289			5.7
		7.76	0.292			5.7
		7.76	0.292			5.7
	Mean	7.72	0.288			5.7
	CV%	0.5	-			-
DDT	6.2	8.84	0.375	0.04	0.07	6.1
		8.85	0.375			6.1
		8.92	0.380			6.1
		8.91	0.380			6.1
		8.95	0.382			6.1
		8.95	0.382			6.1
	Mean	8.90	0.379			6.1
	CV%	0.5	-			-

Table 2.:     Measured and calculated data of Kronitex TXP

Chemical name	Retention time (min)	log k'	log pow	pow	Repeatability Dlog pow log unit
		Calculated data
Kronitex TXP	9.64	0.427	6.36	2287447	0.04
	9.64	0.427	6.36	2287447
	9.74	0.433	6.39	2443532
	9.73	0.433	6.39	2427557
	9.79	0.436	6.40	2524647
	9.79	0.436	6.40	2524647
Mean	9.72	0.432	6.38	2415880
Conf.(95%)	-	-	0.03	170692
CV%	0.7	-	-	-

Conclusions:

In the course of this study the partition coefficient (pow) of Kronitex TXP was determined using high performance liquid chromatography.
Retention time of Kronitex TXP is higher than that of the last eluting standard, therefore an accurate value of log Pow could not be given.
The estimated log Pow: > 6.2
The extrapolated log Pow value calculated for Kronitex TXP: 6.38

Executive summary:

In the course of this study the partition coefficient (p_ow) of Kronitex TXP was determined using high performance liquid chromatography.  Retention time of Kronitex TXP was found to be higher than that of the last eluting standard, therefore an accurate value of log Pow could not be given.

The estimated log Pow:      > 6.2

The extrapolated log Pow value calculated for Kronitex TXP:         6.38

 

Description of key information

Partition coefficient

Key value for chemical safety assessment

Log Kow (Log Pow):

6.38

at the temperature of:

25 °C

Additional information

A single GLP compliant gives the partition coefficient as 6.32 by extrapolation.