N-(dodecylphenyl)naphthalen-1-amine

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:

Between 29 July 1999 and 15 December 1999.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same 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:

OECD draft document (December 1998): Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC).

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

other: Not required

Specific details on test material used for the study:

No further details specified in the study report.

Radiolabelling:

no

Test temperature:

Column temperature: 30°C

Details on study design: HPLC method:

Procedure
Preparation of sample solution
Test material (0.1000 g) was diluted to 100 ml with methanol.

Preparation of reference solutions
The dead time was determined by measuring the retention time of formamide (purity 99.5%, 735 mg/l solution in methanol).

Determination of retention time
The sample, formamide and reference standard solutions were injected in duplicate using the following HPLC parameters:

HPLC system: Hewlett-Packard 1050, incorporating autosampler and workstation
Column: Hypersil 5μ CN-BDS (250 mm x 4.6 mm id)
Column temperature: 30 °C
Mobile phase: methanol: water (55.45 v/v)
pH of mobile phase: 7.01
Flow-rate: 1 ml/min
UV detector wavelength: dead time and reference standards: 210 nm; sample: 217 nm
Injection volume: 10 μl

Construction of calibration curve
A calibration curve was constructed from the retention time data of the formamide and reference standard solutions. The capacity factors (k) for the reference standards were calculated.

Adsorption coefficient sf sample
The capacity factor was calculated using the log10 Koc value determined with reference to the calibration curve.

Key result

Type:

log Koc

Value:

3.63 dimensionless

pH:

7.01

Temp.:

30 °C

Key result

Type:

Koc

Value:

4 240 dimensionless

pH:

7.01

Temp.:

30 °C

Details on results (HPLC method):

The draft document states that the measurement of adsorption coefficient should be carried out on substances in their ionised and unionised forms. However, the dissociation constant of APAN made it impossible to satisfy this criteria. Testing would be required at pH 0.6 or below for the material to be ionised which is outside the environmental pH range for this test.

The retention times of formamide and the reference standards

Dead time	Retention time (mins)		Mean retention time (mins)
	Injection 1	Injection 2
Formamide	3.285	3.287	3.286

 

Standard	Retention time (mins)		Mean retention time (mins)
	Injection 1	Injection 2
Acetanilide	3.576	3.573	3.575
Phenol	3.532	3.532	3.532
Atrazine	4.087	4.088	4.088
Isoproturon	4.293	4.295	4.294
Naphthalene	5.403	5.401	5.402
Fenthion	7.680	7.667	7.674
Pyrazophos	9.391	9.388	9.390
αEndosulfan	16.079	16.151	16.115
Phenanthrene	9.996	10.000	9.998
Diclofop-methyl	15.719	15.712	15.716
DDT	53.842	53.931	53.887

 

The capacity factor (k) and log10 Koc values for the reference standards

Standard	Capacity Factor (k)	Log10 k	Log10 Koc
Acetanilide	8.780 x 10^-2	-1.057	1.25
Phenol	7.486 x 10^-2	-1.126	1.32
Atrazine	0.244	-0.613	1.81
Isoproturon	0.307	-0.513	1.86
Naphthalene	0.644	-0.191	2.75
Fenthion	1.335	0.126	3.31
Pyrazophos	1.857	0.269	3.65
αEndosulfan	3.904	0.592	4.09
Phenanthrene	2.043	0.310	4.09
Diclofop-methyl	3.783	0.578	4.20
DDT	15.399	1.187	5.63

 

The retention times, capacity factors and log10 Koc values determined for the sample

Injection	Retention time (mins)	Capacity factor (k)	Log10 k	Log10 Koc
1	8.965	1.728	0.238	3.63
2	8.945	1.722	0.236	3.63

Overall log10 Koc: 3.63

Adsorption coeifficent: 4.24 x 10³

Validity criteria fulfilled:

not specified

Conclusions:

The adsorption coefficient (Koc) of APAN has been determined to be 4.24 x 103, log10 Koc 3.63.

Executive summary:

Adsorption coefficient determined as 4.24 x 10³, log10 Koc 3.63, using the OECD draft document (December 1998): Estimation of the Adsorption Coefficient (K,) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC).

Description of key information

Adsorption coefficient determined as 4.24 x 10³, log10 Koc 3.63

Key value for chemical safety assessment

Koc at 20 °C:

4 240

Additional information

Adsorption coefficient determined as 4.24 x 10³, log10 Koc 3.63, using the OECD draft document (December 1998): Estimation of the Adsorption Coefficient (K,) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC).

[LogKoc: 3.63]