[No public or meaningful name is available]

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 14 Augustus to 18 September 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, GLP compliant; no restrictions, fully adequate for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

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

Principles of method if other than guideline:

The method guideline states that the measurement of adsorption coefficient should be carried out on substances in their ionised and unionised forms. However, the dissociation constants of certain functional groups found in the test material made it impossible to satisfy these criteria. Testing would be required at approximately greater than pH 12 for the basic functional groups. As pH 12 or above is outside the environmental pH range for this test and also experimentally impractical, testing was carried out at approximately neutral pH with the test material unionised.

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Test material

Test material information

Constituent 1

Radiolabelling:

no

Study design

Test temperature:

30ºC (column temperature)

HPLC method

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: HPLC
- Type: Agilent Technologies 100, incorporating autosampler and workstation
- Type, material and dimension of analytical (guard) column: Phenosphere CN 5µ (250 x 4.6 mm id)
- Detection system: UV detector


MOBILE PHASES
- Type: acetonitrile:reverse osmosis water (55:45 v/v)
- pH: 7.5
- Solutes for dissolving test and reference substances: Test material was dissolved in acetonitril, reference substances were dissolved in methanol.


DETERMINATION OF DEAD TIME
- Method: by measuring retention time of formamide


REFERENCE SUBSTANCES
- Identity: Acetanilide, phenol, atrazine, isoproturon, triadimenol, linuron, naphthalene, endosulfan-diol, α-endosulfan, phenanthrene, diclofop-methyl, DDT.


DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 0.0025 g diluted to 100 ml with acetonitrile
- Quantity of reference substances: between 99 and 111 mg/l


REPETITIONS
- Number of determinations: Two

Results and discussion

Adsorption coefficient

Adsorption coefficient 1

Type:

Koc

Value:

36 800

Adsorption coefficient 2

Type:

log Koc

Value:

4.57

Results: HPLC method

Details on results (HPLC method):

See tables 12 and 13

Any other information on results incl. tables

Table 12 - Reference standards

Standard	Retention time (min)	Capacity factor (k)	Log k	Log koc
Acetanilide	3.536	0.169	-0.772	1.25
Phenol	3.509	0.160	-0.796	1.32
Atrazine	3.748	0.239	-0.621	1.81
Isoproturon	3.898	0.289	-0.540	1.86
Triadimenol	3.932	0.300	-0.523	2.40
Linuron	4.05	0.341	-0.468	2.59
Naphthalene	4.299	0.421	-0.375	2.75
Endosulfan-diol	4.016	0.328	-0.484	3.02
α-endosulfan	5.376	0.777	-0.109	4.09
Phenanthrene	4.829	0.597	-0.224	4.09
Diclofop-methyl	5.108	0.689	-0.162	4.20
DDT	7.078	1.34	0.128	5.63

Table 13 - Sample

Injection	Retention time (min)	Capacity factor (k)	Log k	Log koc
1	5.540	0.832	-0.08	4.56
2	5.543	0.833	-0.079	4.57