hexasodium 5-[(4-{3-[(8-benzamido-1-hydroxy-3,6-disulfonato-2-naphthyl)diazenyl]-4-sulfonatoanilino}-6-[(2-sulfonatoethyl)amino]-1,3,5-triazin-2-yl)amino]isophthalate

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was conducted between 18 July 2007 and 29 August 2007.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Test guideline 1

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:

no

Test guideline 2

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)

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Test material

Test material information

Constituent 1

Reference substance name:

Magenta T-43

IUPAC Name:

Magenta T-43

Test material form:

solid: particulate/powder

Details on test material:

Sponsor's identification: MAGENTA T-43
Description: dark red solid
Storage conditions: room temperature, in the dark
Lot number: H186-5

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material:
Preparation of sample solution:

Test material (0.0102 g) was diluted to 100 ml with reverse osmosis water.

Radiolabelling:

no

Study design

HPLC method

Details on study design: HPLC method:

Preparation of reference solutions:
The dead time was determined by measuring the retention time of formamide (purity 99.5%, 1.02 x E+03 mg/l solution in mobile phase, value quoted by supplier).


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

HPLC System: Agilent Technologies 1100, incorporating autosampler and workstation
Column: Zorbax SB-CN 5µ (250 x 4.6 mm id)
Column temperature: 30°C
Mobile phase: methanol:water (55:45 v/v)
pH of mobile phase: 6.1
Flow-rate: 1ml/min
UV detector wavelength: dead time and reference standards: 210 nm; sample: 525 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.

Calculations
The capacity factors (k) for the reference standards were calculated as follows:

k = tr – t0 / t0

Where:
k = capacity factor
tr = retention time (min)
t0 = dead time (min)

Results and discussion

Adsorption coefficient

Adsorption coefficient 1

Type:

Koc

Value:

< 17.8

Temp.:

30 °C

Adsorption coefficient 2

Type:

log Koc

Value:

< 1.25

Temp.:

30 °C

Results: HPLC method

Details on results (HPLC method):

Calibration
The retention times of formamide and the retention times, capacity factors (k) and log10 Koc values for the reference standards were tabulated.

Adsorption Coefficient of Sample
The retention times, capacity factors and log10 Koc values determined for the sample were tablulated.

The results from the adsorption coefficient analysis were as follows:

Mean log10 Koc: <1.25
Adsorption coefficient: <17.8

Any other information on results incl. tables

Table of Retention Time For Dead Time

Dead Time	Retention Time (mins)		Mean Retention Time (mins)
	Injection 1	Injection 2
Formamide	2.831	2.829	2.830

 

Table Of Retention Times For Standards

Standard	Retention Time (mins)		Mean Retention Time (mins)	Capacity Factor (k)	Log10 k	Log10 Koc
	Injection 1	Injection 2
Acetanilide	4.013	4.032	4.023	0.421	-0.375	1.25
Phenol	3.845	3.850	3.848	0.360	-0.444	1.32
Atrazine	5.954	5.953	5.954	1.10	4.29 x 10^-2	1.81
Isoproturon	6.397	6.406	6.402	1.26	0.101	1.86
Triadimenol	8.937	8.953	8.945	2.16	0.335	2.40
Linuron	9.570	9.568	9.569	2.38	0.377	2.59
Naphthalene	7.961	7.972	7.967	1.82	0.259	2.75
Endosulfan-diol	11.792	11.792	11.792	3.17	0.501	3.02
Fenthion	15.701	15.692	15.697	4.55	0.658	3.31
α-Endosulfan	22.886	22.757	22.822	7.06	0.849	4.09
Phenanthrene	17.725	17.712	17.719	5.26	0.721	4.09
Diclofop-methyl	25.502	25.446	25.474	8.00	0.903	4.20

Table For Adsorption Coefficient Of Sample

Injection	Retention Time (mins)	Capacity Factor (k)	Log10 k	Log10 Koc
1	1.765	<0.421	<-0.375	<1.25
2	1.765	<0.421	<-0.375	<1.25

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The adsorption coefficient (Koc) of the test material has been determined to be <17.8 with a mean log10 Koc <1.25.

Executive summary:

The adsorption coefficient of substance Magenta T-43 was determined to be <17.8, log10 Koc <1.25 according to OECD Test Guideline 121 using the HPLC estimation method.