Bis(2,4-dichlorobenzoyl) peroxide

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well conducted study, according to OECD guideline 117, certificate of analysis included in the report.

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

April 13nd, 2004

Deviations:

yes

Remarks:

The reference substances and test substances were dissolved in methanol.

Principles of method if other than guideline:

The reference substances and test substances were dissolved in methanol.

GLP compliance:

no

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

6

Temp.:

20 °C

Remarks on result:

other: pH not reported

Remarks:

pH not reported

The average retention times of the reference substances as well as the test substance, corrected for the dead time, are presented in the table below. The theoretical log K_owvalues of the reference substances were taken from OECD guideline 117.

 

Substance	log Kowtheor.	Average net retention time (min)	Average log k
Sodium nitrate		0
Aniline	0.9	0.62	-0.33
Phenol	1.5	0.73	-0.26
Methyl benzoate	2.1	1.74	0.12
Bromo benzene	3.0	4.12	0.49
Naphtalene	3.6	5.47	0.61
Phenantrene	4.5	13.70	1.01
4,4’-DDT	6.5	38.02	1.45
bis(2,4-dichlorobenzoyl) peroxide		36.69	1.44

 

In the attachment the graph of the theoretical values of log K_owand the average log k of the reference substances and an example of a HPLC-chromatogram from the analysis performed according to the test set up.

The average measured log K_owvalue for bis(2,4-dichlorobenzoyl) peroxide was calculated with the retention time from two injections usingt he calibration plot of log K_owversus log k of the selected reference substances. The result for log K_owwas determined to be 6.0.

Conclusions:

The partition coefficient log Pow value for bis(2,4-dichlorobenzoyl) peroxide is 6.0.

Executive summary:

The partition coefficient n-octanol/water (K_ow) of bis(2,4-dichlorobenzoyl) peroxide was estimated using the High Performance Liquid Chromatography (HPLC) method. The K_owtest was performed in accordance with the OECD guideline 117 with one modification, the reference substances and test substances were dissolved in methanol. The data on the partition coefficient can be used to predict the adsorption on soil and sediments and for establishing quantitative structure-activity relationships for a wide range of biological effects. Determinations of retention times were performed in duplicate.

Since during analysis the bis(2,4-dichlorobenzoyl) peroxide is separated from polydimethylsiloxane the outcome reflects on the pure substance.

The values of log K_owderived from the different measurements fell within a range of ± 0.1 log units.The correlation coefficient R²for the relationship between log k and log K_owof the reference substances was calculated to be higher than 0.9.

The partition coefficient log Pow value for bis(2,4-dichlorobenzoyl) peroxide is 6.0.

Description of key information

The partition coefficient log Pow  value for bis(2,4-dichlorobenzoyl) peroxide  is 6.0.

Key value for chemical safety assessment

Log Kow (Log Pow):

6

at the temperature of:

20 °C

Additional information

Since during analysis the bis(2,4-dichlorobenzoyl) peroxide is separated from polydimethylsiloxane the outcome reflects on the pure substance.