Benzene, 1-chloro-2,3-dimethyl-

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2003-03-10 to 2003-06-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Adopted March 30, 1989

Deviations:

no

GLP compliance:

yes

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

4.1

Temp.:

23 °C

Remarks on result:

other: no data on pH - however, as test item is non-ionisable, and a methanol/water mixture was used as mobile phase, pH must have been in the neutral range.

Details on results:

The log Pow values calculated individually for each duplicate injection were identical for each peak of the reference substances and the test item.

The t0 was determined to be 1.608 minutes, the value of both measurements. The mean values of the retention times, k' values, log k' values, and log Pow values are summarized in the following table:

Substance	tr^1	k'	log k'	log Pow^2
Reference Substance
Benzyl alcohol	2.000	0.243781	-0.6130	0.96
Toluene	3.135	0.949627	-0.0224	3.0
p-dichlorobenzene	3.737	1.323694	0.1218	3.4
1,2,4-Trichlorobenzene	5.065	2.149876	0.3324	4.2
Fluoranthene	6.183	2.844838	0.4541	4.6
Bibenzyl	6.826	3.244714	0.5112	4.8
Triphenylamine	11.24	5.984142	0.7770	5.7
2,4-DDT	15.85	8.842973	0.9466	6.2
Test item
Peak 1	4.918	2.058458	0.3135	4.1

1) Mean value of the retention times of the two reference substance or test substance chromatograms.

2) Reference substance log Pow as determined from regression - values according to the OECD guideline are given in the methods section.

As a result, the analysis of the test iem samples generated one distinct peak, eluting at 4.92 minutes. The log Pow value for the test iem, detectable with the chromatographic system used and reported using the mean of data from duplicate injections, was calculated as follows:

Peak number: 1

Mean retention time: 4.92

log Pow test item : 4.1

The log Pow values calculated individually for each duplicate injection were identical for each peak of the reference substances and the test item.

Conclusions:

log Pow (OECD 117): 4.10

Executive summary:

Log Pow of the test item was determined according to OECD 117 (1989) compliant with GLP.

A preliminary test was conducted to provide an estimation of the run time to be used during the definitive test. This was accomplished by injecting the test substance in the HPLC system and recording the chromatogram for 30 minutes. Thereafter, the solutions were injected in the following sequence: the mixture of reference substances, a blank (acetonitrile diluted 1:10 with the mobile phase), the formamide solution, the test solution (in duplicate), a blank (acetonitrile), the mixture of reference substances (reference substances were injected separately during method validation), and the formamide solution. The run time for all solutions was established at 30 minutes. The analysis of 1-chloro-2,3-dimethylbenzene samples generated one distinct peak, eluting at 4.92 minutes. The log Pow value for the test item, detectable with the chromatographic system used, was calculated as follows:

Peak number: 1

Mean retention time: 4.92

log Pow test item : 4.1

The log Pow values calculated individually for each duplicate injection were identical for each peak of the reference substances and the test item.

Description of key information

log Pow (OECD 117): 4.10

Key value for chemical safety assessment

Log Kow (Log Pow):

4.1

at the temperature of:

23 °C

Additional information

Log Pow of the test item was determined according to OECD 117 (1989) compliant with GLP.

A preliminary test was conducted to provide an estimation of the run time to be used during the definitive test. This was accomplished by injecting the test substance in the HPLC system and recording the chromatogram for 30 minutes. Thereafter, the solutions were injected in the following sequence: the mixture of reference substances, a blank (acetonitrile diluted 1:10 with the mobile phase), the formamide solution, the test solution (in duplicate), a blank (acetonitrile), the mixture of reference substances (reference substances were injected separately during method validation), and the formamide solution. The run time for all solutions was established at 30 minutes. The analysis of 1-chloro-2,3-dimethylbenzene samples generated one distinct peak, eluting at 4.92 minutes. The log Pow value for the test item, detectable with the chromatographic system used, was calculated as follows:

Peak number: 1

Mean retention time: 4.92

log Pow test item : 4.1

The log Pow values calculated individually for each duplicate injection were identical for each peak of the reference substances and the test item.