1-bromo-4-(trans-4-ethylcyclohexyl)benzene

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20.10. - 17.11.2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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))

Version / remarks:

2001

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

sewage sludge

Radiolabelling:

no

Test temperature:

25 °C

Details on study design: HPLC method:

HPLC equipment: HPLC System and variable wavelength detector
Column: Stationary phase cyanopropyl solid phase
Mobile phase: Methanol/distilled water

Analytical monitoring:

not required

Key result

Type:

log Koc

Value:

4.97 dimensionless

Temp.:

25 °C

Table 1: Determination of the dead time t0

Dead time marker	tR/min 1stinjection	tR/min 2ndinjection	tR/min 3rdinjection
Formamide	3.425	3.426	3.426

 

 dead time t0=3.426 min

 

Table 2: Calibration data 1stinjection

Calibration substance	tR/min	k	Log k	Log Koc
Acetanilide	3.924	0.15	-0.84	1.25
Phenole	3.887	0.13	-0.87	1.32
Atrazin	4.034	0.18	-0.75	1.81
Monuron	4.213	0.23	-0.64	1.99
Triadimenol	4.346	0.27	-0.57	2.40
Linuron	4.724	0.38	-0.42	2.59
Pyrazophos	5.395	0.57	-0.24	3.65
Diclofop-methyl	5.665	0.65	-0.18	4.20

 

Regression: log Koc= a+ b · log k

Parameters: a=-4.64, b=3.98, r2=0.9632

 

Table 3: Log Kocof the test item 1stinjection

	tR/min	k	Log k	Log Koc
Test item	7.565	1.21	0.08	4.97 />4.20*)

*beyond log Koc value of the highest calibration substance (Diclofop-methyl)

 

Table 4: Calibration data 2ndinjection

Calibration substance	tR/min	k	Log k	Log Koc
Acetanilide	3.926	0.15	-0.84	1.25
Phenole	3.887	0.13	-0.87	1.32
Atrazin	4.037	0.18	-0.75	1.81
Monuron	4.213	0.23	-0.64	1.99
Triadimenol	4.347	0.27	-0.57	2.40
Linuron	4.726	0.38	-0.42	2.59
Pyrazophos	5.396	0.58	-0.24	3.65
Diclofop-methyl	5.666	0.65	-0.18	4.20

 

Regression: log Koc= a+ b · log k

Parameters: a =4.64, b =3.98, r2=0.9632

 

Table 5: Log Powof the test item 2ndinjection

	tR/min	k	Log k	Log Koc
Test item	7.565	1.21	0.08	4.97 / >4.20*

*beyond log Koc value of the highest calibration substance (Diclofop-methyl)

 

Within two injections, theadsorption coefficientKocof the test item was determined to be:

Log Koc=>4.97

 

Validity criteria fulfilled:

yes

Conclusions:

The adsorption coefficient of the lest item was determined according to the "HPLC- method" described in guideline OECD 121. The adsorption coefficient of the test item was found to be:Log Koc = 4.97

Executive summary:

A study was conducted in accordance with OECD 121 and67/548/EEC annex C.19. to determine theadsorption coefficient of the test substance using the HPLCmethod. The adsorption coefficient of the test substance was derived from its retention time and the calibration graph. The retention time of the test item was above the retention time of the highest calibration standard (log Koc) and thus out of the calibration range. Therefore, the dsorption coefficient of the test substance was determined to be above 4.2 and estimated to be Log K_oc=4.97.

Key value for chemical safety assessment

Koc at 20 °C:

4.97

Additional information

A study was conducted in accordance with OECD 121 and 67/548/EEC annex C.19. to determine theadsorption coefficient of the test substance using the HPLCmethod. The adsorption coefficient of the test substance was derived from its retention time and the calibration graph. The retention time of the test item was above the retention time of the highest calibration standard (log Koc 4.2) and thus out of the calibration range. Therefore, the adsorption coefficient of the test substance was determined to be above 4.2 and estimated to beLog Koc= 4.97