Hydrogen bis[1-[(5-chloro-2-hydroxyphenyl)azo]-2-naphtholato(2-)]chromate(1-)

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

06 December 2017 - 15 December 2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

27 July 1995

Deviations:

yes

Remarks:

methodological limitations, e.g. inconsistent analytical procedures, insufficient reporting of measured conc.

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Test material

Test material information

Constituent 1

Reference substance name:

Hydrogen bis[1-[(5-chloro-2-hydroxyphenyl)azo]-2-naphtholato(2-)]chromate(1-)

EC Number:

250-774-0

EC Name:

Hydrogen bis[1-[(5-chloro-2-hydroxyphenyl)azo]-2-naphtholato(2-)]chromate(1-)

Cas Number:

31714-55-3

Molecular formula:

C32H19Cl2CrN4O4

IUPAC Name:

[1-{[5-chloro-2-(hydroxy-kappaO)phenyl]diazenyl}-2-naphtholato(2-)-kappaO]{1-[(5-chloro-2-hydroxyphenyl)diazenyl]-2-naphtholato-kappaO}chromium

Test material form:

solid: particulate/powder

Details on test material:

- Appearance: Black powder
- Storage conditions: At room temperature

Results and discussion

Water solubility

Key result

Water solubility:

< 0.16 mg/L

Conc. based on:

test mat.

Incubation duration:

72 h

pH:

> 6.02 - < 6.07

Remarks on result:

other: There was no detectable response for the test item observed in filtered samples from the test at any time point.

Details on results:

Analytical method:
- The correlation coefficient (r) was 0.999, 0.999 and 0.998 for calibration curves prepared at 24, 48 and 72 hours.
- There was no peak observed in the chromatograms of the undiluted filtered test samples from the flask method test at all time points. Therefore, the LOD of the method at each measurement time point was determined from the signal to noise ratio (S/N) in the chromatogram of the lowest linearity standard solution (see table 3)

Any other information on results incl. tables

Table 2       Accuracy (% Recovery) and Precision (% RSD)

Overall Mean Accuracy (% Recovery) in Distilled Water^#
100.98 ± 0.57
Precision (% RSD)
Distilled Water	Fortification Level	% RSD	Overall % RSD
	I	0.22	0.56
	II	0.37
	III	0.12

Table 3       Overview of LOD per measurement time point

Time Interval (hr)	Signal to Noise	Limit of Quantification
24	95.66	0.16
48	67.10	0.22
72	140.41	0.11

  Based on the above derived LOD values (mean LOD is 0.16 mg/L), the water solubility of the test item is estimated to be < 0.16 mg/L.

Applicant's summary and conclusion

Conclusions:

The water solubility of T-95/T-99 was determined to be <0.16 mg/L.

Executive summary:

A water solubility test was performed according to OECD guideline 105 and GLP principle to assess the water solubility of T-95/T-99 by using the flask method.

At the end of the test, pH in filtered test samples ranged from 6.02 -6.07. Since there was no peak observed in the chromatograms of the undiluted filtered test samples at all time points (i.e. 24, 48 and 72 h), the LOD of the method at each measurement time point was determined from the signal to noise ratio (S/N) in the chromatogram of the lowest linearity standard solution. Based on these results (mean LOD was 0.16 mg/L), the water solubility of T-95/T-99 was determined to be <0.16 mg/L.