Tris(2-hydroxyethyl)ammonium chloride

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19. Mar. 2018 to 29. Mar. 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Key result

Water solubility:

353.8 g/L

Conc. based on:

test mat.

Loading of aqueous phase:

1 250 g/L

Incubation duration:

6 d

Temp.:

20 °C

pH:

>= 5.29 - <= 5.33

Measurements during Equilibration

 

Time [h] (flask)	Tempera ture [°C]	pH*	Dilution factor	Peak area [mAU*min]	Concentration test item [g/L]	Difference to previous sample [%]
22.1 (1A)	19.5	6-7	320000	93328.7	302.7
				98974.8
46.3 (1B)	19.5	6-7	320000	99210.6	331.7	+9.6 %
				110953.4
70.1 (1C)	19.5	6-7	320000	114435.9	352.0	+6.1 %
				108219.0
94.0 (1A)	20.5	6-7	640000	69015.0	359.6	+2.2 %
				68764.8
118.3 (1B)	20.5	6-7	640000	70636.3	365.6	+1.7 %
				69359.6
142.0 (1C)	20.5	6-7	640000	69922.9	366.2	+0.1 %
				70264.2

 

As no rising tendency was observed between samplings at 118.3 h and 142.0 h, the plateau was considered reached and sampling of flasks 2-6 was performed

 

Measurements at Plateau

 

Flask	Temperature [°C]	pH	Dilution factor	Peak area [mAU*min]	Measured values [g/L]
Blank	19.5	7	-	461.5	< LOQ
				507.9
2wdh	20.0	5.29	640000	63330.0	351.7
				62866.8
3wdh	20.0	5.29	640000	61692.8	342.8
				61459.1
4wdh	20.0	5.31	640000	64585.5	360.8
				64720.9
5wdh	20.0	5.33	640000	65959.4	366.6
				65315.6
6wdh	20.0	5.31	640000	62463.5	346.9
				62084.3

 

pH at the plateau was tested using a calibrated pH meter except blank was tested using pH paper

 

The measurements after 6 d incubation (flasks 2wdh – 6wdh) were used for the calculation of the solubility of the test item in water.

 

Flask	Concentration [mg/L]	Total Mean [mg/L]	Total Standard Deviation [mg/L] (RSD* [%])
2	351.7	353.8	8.8 (2.5)
3	342.8
4	360.8
5	366.6
6	346.9

 

Conclusions:

The water solubility of the test item was determined to be 353.8 g/L at pH 5.29 - 5.33 and 20 °C.

Executive summary:

The water solubility was determined according to OECD 105 using the shake flask method with HPLC analysis. About 25 g test substance was weighed into 100 mL stoppered Erlenmeyer flasks (nine parallels) according to the estimated solubility based on the Preliminary Test. After the addition of 10 or 5 mL ultra-pure water, the flasks were agitated at 30 °C. The six vessels (for the sampling point 72 h) were set onto the shaking apparatus immediately and shaking was started.As no rising tendency was observed between samplings at 118.3 h and 142.0 h, the plateau was considered reached and sampling of flasks 2-6 was performed.The aqueous samples (about 2-4 mL) were membrane filtrated (0.45 µm, nylon) to exclude the presence of undissolved particles. Then, an appropriate volume was diluted with demineralised water and prepared for measurement. The pH of each sample was recorded. The water solubility of the test substance was determined to be 353.8 ± 8.8 g/L (95 % confidence interval) at 20 °C ± 1 °C (pH 5.29 to 5.33).

Description of key information

The water solubility of the test item was determined to be 353.8 g/L at pH 5.29 - 5.33 and 20 °C.

Key value for chemical safety assessment

Water solubility:

353.8 g/L

at the temperature of:

20 °C

Additional information

The water solubility was determined according to OECD 105 using the shake flask method with HPLC analysis. About 25 g test substance was weighed into 100 mL stoppered Erlenmeyer flasks (nine parallels) according to the estimated solubility based on the Preliminary Test. After the addition of 10 or 5 mL ultra-pure water, the flasks were agitated at 30 °C. The six vessels (for the sampling point 72 h) were set onto the shaking apparatus immediately and shaking was started. As no rising tendency was observed between samplings at 118.3 h and 142.0 h, the plateau was considered reached and sampling of flasks 2-6 was performed. The aqueous samples (about 2-4 mL) were membrane filtrated (0.45 µm, nylon) to exclude the presence of undissolved particles. Then, an appropriate volume was diluted with demineralised water and prepared for measurement. The pH of each sample was recorded. The water solubility of the test substance was determined to be 353.8 ± 8.8 g/L (95 % confidence interval) at 20 °C ± 1 °C (pH 5.29 to 5.33) (reference 4.8 -1).