1,2-dihydroxyanthraquinone

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30/01/2017 to 04/04/2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

column elution method

Test material

Test material information

Constituent 1

Reference substance name:

1,2-dihydroxyanthraquinone

EC Number:

200-782-5

EC Name:

1,2-dihydroxyanthraquinone

Cas Number:

72-48-0

Molecular formula:

C14H8O4

IUPAC Name:

1,2-dihydroxy-9,10-dihydroanthracene-9,10-dione

Test material form:

solid: particulate/powder

Details on test material:

- Appearance: solid yellow powder

Results and discussion

Water solubility

Key result

Water solubility:

0.483 mg/L

Conc. based on:

test mat.

Temp.:

20 °C

pH:

4.5

Any other information on results incl. tables

Preliminary test result:

Test Item [mg]	total volume of ultra-pure water [mL]	time of shaking [min]	remarks	Approximate solubility [mg/L]
	100	10	not completely dissolved	< 101
10.1	200	10	not completely dissolved	< 50.5
	300	10	not completely dissolved	< 33.7
	400	10	not completely dissolved	< 25.3
	500	10	not completely dissolved	< 20.2
	1000	10	not completely dissolved	< 10.1
	1000	17 hours	not completely dissolved	< 10.1
	1100	74 hours	not completely dissolved	< 9.2

The minimum amount of test item needed for the main test is: 5 x 9.2 mg/L = 46 mg/L = 2.3 mg/50 mL

Main test:

Amount of test item in each column: ≥ 2.5 mg at 50 mLwater

sampling time	Analyte concentration column 1 (25 mL/h)	Analyte concentration column 2 (8 mL/h)	pH value column 1	pH value column 2
[h]	[mg/L]	[mg/L]
405	0.512	0.598	4.5	4.5
429	0.338	0.373	4.5	4.5
453	0.461	0.513	4.5	4.5
479	0.424	0.577	4.5	4.5
501	0.478	0.551	4.5	4.5
Mean:*	0.443	0.522	4.5	4.5
SD:*	0.067	0.089	0.0	0.0
RSD [%]:*	15.1	17.0	0.0	0.0

	Analyte concentration [mg/L]	pH Value
Overall mean:*	0.483	4.5
Overall AD:*	0.079	0.0
Overall RD [%]:*	16.4	0.0

SD: standard deviation; RSD: relative standard deviation; AD: absolute deviation; RD: relative deviation

* : values were calculated from the last 5 consecutive samples

 

The results indicate the required reproducibility (relative standard deviation below 30 %) and no tendency to increasing values, when the test time is prolonged.

The mean values obtained from the two tests with different flows did not differ by more than 30 %.

The analytical method used was validated. The calibration curve was linear with R= 1. The LOQ was set at 0.2318 mg/L and LOD at 0.1 mg/L. The recovery was found to be 98.6 % and 99.9 % for 0.2318 and 1.714 mg/L respectively.

Applicant's summary and conclusion

Conclusions:

The water solubility was determined to be 0.483 mg/L (20°C, pH 4.5).

Executive summary:

In the current study the water solubility of the test item was determinde according to OECD guideline 105 (1995) and Council Regulation (EC) No. 440/2008 Method A.6. The study was according to GLP. The solubility of the test item was determined using the column elution method at 20 +/- 0.5°C.

The HPLC method (HPLC with UV detection ) for the determination of the content of Mordant Red 11 in aquaeous solutions was validated and tested with satisfactory results in regard to linearity of the detector, accuracy, precision and non-analyte interference of the analytical system.

The water solubility was determined to be 0.483 mg/L (20°C, pH 4.5).