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

Partition coefficient

Administrative data

Endpoint:

partition coefficient

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 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

shake-flask method to: flask method

Partition coefficient type:

octanol-water

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

Study design

Analytical method:

other: Spectrophotometric

Results and discussion

Partition coefficient

Type:

log Pow

Partition coefficient:

< -4.01

Temp.:

23 °C

pH:

7.1

Any other information on results incl. tables

Preliminary estimate:

Approximate solubility in n-octanol: <6.00 x 10^-3g/l

Approximate solubility in water: >50.1 g/l

Approximate Pow: <1.20 x 10^-4

Logl0 Pow: < -3.92

Definitive test

 

The absorbances obtained for the standard, stock and sample solutions are shown in the following tables.

 

Organic Phase

 

Solution	Absorbance
Standard 0.509 mg/l	3.827 x 10^-2
Sample 1	<3.827 x 10^-2
Sample 2	<3.827 x 10^-2
Sample 3	<3.827 x 10^-2
Sample 4	<3.827 x 10^-2
Sample 5	<3.827 x 10^-2
Sample 6	<3.827 x 10^-2

 

Aqueous Phase

Solution	Absorbance
Standard 20.1 mg/l	0.401
Standard 21.3 mg/l	0.457
Sample 1	0.446
Sample 2	0.438
Sample 3	0.427
Sample 4	0.441
Sample 5	0.443
Sample 6	0.451
Stock solution A	0.430
Stock solution B	0.422

The total weights (mg) and analysed concentration (mg/l) of the respective phases are shown in

the following table:

 

Sample Number	Volume of water saturated n-octanol (ml)	Volume of Stock Solution (ml)	Total Weight (mg)*	Organic Phase		Aqueous Phase
				Analysed Conc. (mg/ml)	Weight (mg)†	Analysed Conc. (mg/l)	Weight (mg)†	pH
1	240	80	824	<1.018	<0.244	1.08 x 10^4	862	7.1
2	240	80	824	<1.018	<0.244	1.06 x 10^4	846	7.1
3	280	40	412	<1.018	<0.285	1.03 x 10^4	412	7.1
4	294	42	432	<1.018	<0.299	1.07 x 10^4	447	7.1
5	315	21	216	<1.018	<0.321	1.07 x 10^4	225	7.2
6	315	21	216	<1.018	<0.321	1.09 x 10^4	229	7.2

 

pH of stock solution: 7.0

Temperature: 22.5±0.5°C

 

*= From analysis of the stick solution

†= from analysis of respective phase

 

 

The partition coefficient determined for each sample is shown in the following table:

Sample Number	n-Octanol/Water Volume Ratio	Partition Coefficient	Log10Pow	Partition Coefficient
1	3:1	<9.45 x 10^-5	< - 4.03	<9.62 x 10^-5
2		<9.62 x 10^-5	< -4.02
3	7:1	<9.88 x 10^-5	< - 4.01	<9.88 x 10^-5
4		<9.56 x 10^-5	< - 4.02
5	15:1	<9.51 x 10^-5	< - 4.02	<9.51 x 10^-5
6		<9.34 x 10^-5	< - 4.03

Pow: <9.88 X 10 ^-5

Log10 Pow:<-4.01

Validation

The linearity of the detector response with respect to concentration for the aqueous phases was assessed over the nominal concentration range of 0 to 33 mg/l. This was satisfactory with a correlation coefficient of 1.00 being obtained.

Applicant's summary and conclusion

Conclusions:

The partition coefficient of the test material has been determined to be <9.88 x E-05 at 22.5 ±0.5 °C, log10 Pow <- 4.01.

Executive summary:

The partition coefficient of substance Magenta T-43 was determined to be <9.88 x 10^-5 at 22.5 ± 0.5 °C, log10 Pow <-4.01 according to the OECD Test Guideline 107 using the shake-flask method.