Hatcol 1760

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Testing was conducted between 14 February 2008 and 31 March 2008.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Report date:

2008

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method C.19 (Estimation of the Adsorption Coefficient (KOC) on Soil and Sewage Sludge Using High Performance Liquid Chromatography (HPLC))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

The work described was performed in compliance with UK GLP standards (Schedule 1, Good Laboratory Practice Regulations 1999 (SI 1999/3106 as amended by SI 2004/0994)). Date of inspection: 21/08/2007. Date of signature: 23/04/2008.

Type of method:

HPLC estimation method

Media:

other: methanol

Test material

Test material information

Constituent 1

Details on test material:

Sponsor's identification :Hatcol 1760
Description : clear colourless slightly viscous liquid
Purity : >99%
Date received : 04 February 2008
Storage conditions :room temperature, in the dark

Radiolabelling:

no

Study design

Test temperature:

40°C

HPLC method

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: HPLC
- Type: Agilent Technologies 1100, incorporating autosampler and workstation
- Type, material and dimension of analytical (guard) column: Zorbax SB-CN 5µm (250 x 4.6 mm id)
- Detection system: UV - dead time and reference standards: 210 nm
sample: 210 nm


MOBILE PHASES
- Type:
- Experiments with additives carried out on separate columns: no
- pH: 6.4
- Solutes for dissolving test and reference substances: methanol


DETERMINATION OF DEAD TIME
- Method: by means of homologous series.


REFERENCE SUBSTANCES
- Identity: Acetanilide, Phenol, Atrazine, Isoproturon, Triadimenol, Linuron, Naphthalene, Endosulfan-diol, Fenthion, alpha-Endosulfan, Phenanthrene, Diclofop-methyl, DDT


DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 25 µl
- Quantity of reference substances: 25 µl
- Intervals of calibration:

As the test material had a high affinity for the stationary phase of the column, the mobile phase was ramped to 100% acetonitrile shortly after the retention time of DDT, to elute the sample.

REPETITIONS
- Number of determinations: duplicate (x2)


EVALUATION
- Calculation of capacity factors k':
The capacity factor was determined using the following equation:

K = (tr – to) / to
where:
k = capacity factor
tr = retention time (min)
t0 = dead time (min)


- Calculation of retention times: not stated in report.

- Determination of the log Koc value:
The adsorption coefficient was calculated using the following equation:
Log10 Koc = (Log10 k – A) / B

where:
Koc = adsorption coefficient
k = capacity factor
A = intercept of the calibration curve
B = slope of the calibration curve

Results and discussion

Adsorption coefficient

Adsorption coefficient 1

Type:

Koc

Value:

> 427 000

Adsorption coefficient 2

Type:

log Koc

Value:

> 5.63

Results: HPLC method

Details on results (HPLC method):

- Retention times of reference substances used for calibration: Please see section "Remarks on results including tables and figures"

- Details of fitted regression line: Log k' vs. log Koc

- Graph of regression line attached: Yes

- Average retention data for test substance: 40 minutes

Any other information on results incl. tables

Calibration

The retention times of formamide and the retention times, capacity factors (k) and log₁₀K_ocvalues for the reference standards are shown in the two following tables:

Dead Time	Retention Time (mins)		Mean Retention Time (mins)
	Injection 1	Injection 2
Formamide	2.797	2.797	2.797

Standard	Retention Time (mins)		Mean Retention Time (mins)	Capacity Factor (k)	Log10k	Log10Koc
	Injection 1	Injection 2
Acetanilide	3.715	3.715	3.715	0.328	-0.484	1.25
Phenol	3.551	3.552	3.552	0.270	-0.569	1.32
Atrazine	5.176	5.175	5.176	0.850	-7.04 x 10^-2	1.81
Isoproturon	5.413	5.412	5.413	0.935	-2.91 x 10^-2	1.86
Triadimenol	6.956	6.953	6.955	1.49	0.172	2.40
Linuron	7.235	7.236	7.236	1.59	0.201	2.59
Naphthalene	6.358	6.359	6.359	1.27	0.105	2.75
Endosulfan-diol	8.355	8.355	8.355	1.99	0.298	3.02
Fenthion	10.637	10.639	10.638	2.80	0.448	3.31
a-Endosulfan	14.649	14.651	14.650	4.24	0.627	4.09
Phenanthrene	12.287	12.290	12.289	3.39	0.531	4.09
Diclofop-methyl	16.371	16.385	16.378	4.86	0.686	4.20
DDT	31.873	31.881	31.877	10.4	1.02	5.63

Adsorption coefficient of sample

The retention times, capacity factors and log₁₀K_ocvalues determined for the sample are shown in the following table:

Injection	Retention Time (mins)	Capacity Factor (k)	Log10k	Log10Koc
1	40.355	>10.4	>1.02	>5.63
2	40.357	>10.4	>1.02	>5.63

Mean log₁₀K_oc:                       >5.63
Adsorption coefficient: >4.27 x 10⁵

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The adsorption coefficient (Koc) of the test material has been determined to be >4.27 x 105, log10 Koc >5.63.

Executive summary:

Method

The determination was carried out using the HPLC screening method, Method C19 of Commission Directive 2001/59/EC (which constitutes Annex V of Council Directive 67/548/EEC).

Conclusion

The adsorption coefficient (K_oc) of the test material has been determined to be >4.27 x 10⁵, log₁₀ K_oc >5.63.