1,1'-(1,1-dimethyl-3-methylene-1,3-propanediyl)bisbenzene

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:

Experimental start date: 10 September 2012. Experimental completion date: 15 September 2012.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Data obtained under GLP conditions.

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))

GLP compliance:

yes (incl. QA statement)

Test temperature:

20 °C

Details on study design: HPLC method:

TEST SYSTEM
The test utilised a high performance liquid chromatograph and a commercially available cyanopropyl reverse phase HPLC column containing lipophilic and polar moieties.

PERFORMANCE OF THE TEST
- Preparation of sample solution: test item (0.0998 g) was diluted to 100 mL with methanol (MeOH) to give a concentration of 0.998 g/L.
- Preparation of deadtime solution: the dead time was determined by measuring the retention time of formamide (purity 99.94 %, 603 mg/L solution MeOH:reverse osmosis water 55:45 v/v)
- Preparations of reference standard solutions: solutions of reference substance were prepared in MeOH

DETERMINATION OF RETENTION TIME
The sample, deadtime and reference standard solutions were injected in duplicate using the following HPLC parameters
HPLC system: Agilent Technologies 1100 series, incorporating autosampler
Column: Waters CN 5 µm (150 x 4.6 ,, id)
Column temperature: 30 °
Mobile phase: MeOH:reverse osmosis water (55:45 v/v)
pH of mobile phase: 6.38
Flow-rate: 1.0 mL/min
Injection volume: 10 µL
UV detector wavelength: dead time and reference standards: 210 nm
sample: 240 nm

Type:

Koc

Value:

65 700

Temp.:

30 °C

Type:

log Koc

Value:

4.82

Temp.:

30 °C

Details on results (HPLC method):

- Graph of regression line attached

Calibration

The retention times of the dead time and the retention time, capacity factors (k’) and log­₁₀K_ocvalues for the reference standards are shown below:

Dead time	Retention time (min)		Mean retention time (min)
	Injection 1	Injection 2
Formamide	1.885	1.885	1.885

 

Standard	Retention time (min)		Mean retention time (min)	Capacity factor (k’)	Log10k’	Log10Koc
	Injection 1	Injection 2
Phenol	2.536	2.536	2.536	0.345	-0.462	1.32
Atrazine	3.751	3.751	3.751	0.990	-4.50 x 10^-3	1.81
Isoproturon	1.4057	4.052	4.055	1.15	6.10 x 10^-2	1.86
Triadimenol	5.641	5.641	5.641	1.99	0.299	2.40
Linuron	5.821	5.821	5.821	2.09	0.320	2.59
Naphthalene	4.956	4.956	4.956	1.63	0.212	2.75
Endosulfan-diol	7.420	7.425	7.422	2.94	0.468	3.02
Fenthion	8.931	8.931	8.931	3.74	0.573	3.31
a-Endosulfan	13.081	13.081	13.081	5.94	0.774	4.09
Diclofop-methyl	14.043	14.038	14.040	6.45	0.809	4.20
Phenanthrene	9.742	9.747	9.745	4.17	0.620	4.09
DDT	28.984	28.994	28.989	14.4	1.16	5.63

 

Adsorption coefficient of sample

The retention times, capacity factor and log₁₀K_ocvalue determined for the sample are shown in the following table:

Injection	Retention time (min)	Capacity factor (k’)	Log10k’	Log10Koc	Mean Log10Koc	Adsorption coefficient
1	19.869	9.54	0.980	4.82	4.82	6.57 x 10^4
2	19.927	9.57	0.981	4.82

 

Overall log₁₀K_oc: 4.82

Adsorption coefficient: 6.57 x 10⁴

Validity criteria fulfilled:

yes

Conclusions:

The adsorption coefficient (Koc) of the test item was assessed according to OECD Guideline 121 and determined to be 6.57 x 10^4, Log10 Koc 4.82.

Description of key information

The adsorption coefficient (Koc) of the test item was assessed according to OECD Guideline 121 and determined to be 6.57 x 10^4, Log10 Koc 4.82.

Key value for chemical safety assessment

Koc at 20 °C:

65 700