1,2,4,5,7,8-Hexoxonane, 3,6,9-trimethyl-, 3,6,9-tris(Ethyl and Propyl) derivatives (upper limit: 41% w/w; typical concentration: 38% w/w)

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well conducted GLP study according to OECD Guideline 121

Qualifier:

according to guideline

Guideline:

OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))

Deviations:

yes

Remarks:

The test and reference substances were prepared and dissolved in methanol instead of the mobile phase, due to solubility issues of the test substance

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Radiolabelling:

no

Details on study design: HPLC method:

• Autosampler: Spark, model Midas
• Pump: Spark, model 1000 HPLC pump
• Column: Alltech, Platinum CN 100A 5µ 150mm without guard column
• Column temp.: 30 ºC
• Mobile Phase: Methanol : Water 40 : 60 (v/v)
• Flow rate: 0.7 mL/min
• Detector: Separations UV/VIS detector Smartline 2500
• Wavelength: 210 nm
• Software Dionex, Chromeleon version 7.2.2.6394

Analytical monitoring:

yes

Details on sampling:

The test substance as well as the reference substances were measured in duplicate. For the test substance and each reference substance a stock solution was prepared by weighing exact amounts of substance in 50 mL volumetric flasks. The volumetric flasks were filled up to the mark with methanol. Dilutions from these stock solutions were made in methanol and analyzed using the conditions described above. In table II the concentrations of the stock solutions from the test substance and reference substances are described, together with the final injection concentrations after dilution.

Table II: Stock solution concentrations test and reference substances and there injection concentration
Substance Stock concentration (mg/L) Injection concentration (mg/L)
Sodium nitrate (dead time) 1062 20
Acetanilide 194 10
Methylbenzoate 688 10
Aniline 1226 10
Naphthalene 704 10
1,2,3-trichlorobenzene 570 10
Phenantrene 432 10
Test substance 10144 5000

Details on matrix:

Test substance and reference substances were prepared and dissolved in methanol.

Type:

log Koc

Value:

1.9

Details on results (HPLC method):

In the test, the adsorption coefficient (Koc) was deduced from the capacity factor (k) using a calibration plot of Log Koc versus Log k of the selected reference substances. The test substance was measured in duplicate and this resulted in an average Log Koc value of 1.9.

The retention times are depicted in a table in paragraph 'any other information on results incl. tables'
The details of fitted regression line (log k' vs. log Koc) are depicted in section 'Illustration (picture/graph)'

Table: Average retention times of the reference substances and test substance

Substance	Log Koc theoretical	Average Retention time (min)	Average Log k
Sodium nitrate (dead time)		1.630
Acetanilide	1.25	2.988	-0.08
Methylbenzoate	1.8	3.219	-0.01
Aniline	2.07	3.051	-0.06
Naphthalene	2.75	4.018	0.17
1,2,3-trichlorobenzene	3.16	3.773	0.12
Phenantrene	4.09	5.478	0.37
Test substance		3.165	-0.03

Conclusions:

In the test, the adsorption coefficient (Koc) was deduced from the capacity factor (k) using a calibration plot of Log Koc versus Log k of the selected reference substances. The test substance was measured in duplicate and this resulted in an average Log Koc value of 1.9.

Executive summary:

Well described GLP study, carried out according to OECD guideline.

Description of key information

The results of an OECD 121 study indicated that the log Koc is 1.9

Key value for chemical safety assessment

Koc at 20 °C:

79.4

Additional information

In the test, the adsorption coefficient (Koc) was deduced from the capacity factor (k) using a calibration plot of Log Koc versus Log k of the selected reference substances. The test substance was measured in duplicate and this resulted in an average Log Koc value of 1.9.

[LogKoc: 1.9]