Pentapotassium bis(peroxymonosulphate) bis(sulphate)

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2001-02-22 - 2002-01-17

Reliability:

1 (reliable without restriction)

Reason / purpose for cross-reference:

reference to other study

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

Principles of method if other than guideline:

NA

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:

< 0.3

Temp.:

20 °C

pH:

ca. 1

Details on results:

pH dependence is not expected.

Conclusions:

The partition coefficient (log Pow) of the test substance Oxone Monopersulfate compound was determined to be < 0.3 at 20°C. A dependence on the pH values is not expected.

Executive summary:

The partition coefficient (log Pow) of the test substance Oxone® Monopersulfate compound was determined to be < 0.3 at 20 °C.

In order to correlate the measured capacity factor (k) of the test material with its log Pow, two reference compounds were selected in order to demonstrate that they were themselves retained under the experimental conditions employed.

Description of key information

In accordance with column 2 of REACH Annex VII, the determination of the partition coefficient in n-octanol/water (required in section 7.8) does not need to be conducted for inorganic substances. However, for hypothetical / theoretical considerations the results of one key study and one supporting study were taken for estimation of the partition coefficient.Potassium peroxomonosulfate (2 KHSO5), potassium hydrogen sulfate (KHSO4) and potassium sulfate (K2SO4) (CAS# 70693 -62 -8). The calculation was done by using the programme KOWWIN, Log Octanol-Water Partition Coefficient Program, v1.67 (© 2000 U.S. EPA). The calculated log Pow for Potassium peroxomonosulfate (CAS# 10058-23-8) was - 3.90.

Key value for chemical safety assessment

Log Kow (Log Pow):

-3.9

at the temperature of:

25 °C

Additional information

For hypothetical / theoretical considerations the results of one key and one supporting study were taken for estimation of the partition coefficient. In an experimental study the partition coefficient of the test substance was determined to a log Pow of < 0.3 at 20 °C and pH ~1 applying HPLC. A dependence on the pH range was not expected. Additionally, a calculation of the log Pow was performed for Potassium peroxomonosulfate (CAS# 10058-23-8) but not for the triple salt comprising Potassium peroxomonosulfate (2 KHSO5), potassium hydrogen sulfate (KHSO4) and potassium sulfate (K2SO4) (CAS# 70693 -62 -8). The calculation was done by using the programme KOWWIN, Log Octanol-Water Partition Coefficient Program, v1.67 (EPIWIN v4.0, 2008). Although QSAR models like KOWWIN are not able to robustly estimate log Pow values of inorganic substances, the value provided for Potassium peroxomonosulfate (CAS# 10058-23-8) (log Pow = - 3.9) was in the range expected for inorganic salts.