O-phosphoserine

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2017-08-21 to 2017-09-01

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

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7840 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

TOXI-COOP ZRT., 8230 Balatonfüred, Arácsi út 97., Hungary

Type of method:

flask method

Key result

Water solubility:

28.34 g/L

Conc. based on:

test mat.

Incubation duration:

>= 24 - <= 72 h

Temp.:

20 °C

pH:

>= 1.73 - <= 1.81

Details on results:

Preliminary test
The water solubility of the test item was estimated to be ca. 32.9 g/L in a preliminary test, therefore the shake-flask method was used in the main test.
Calibration
The calibration solutions were prepared in 0.5 – 50 μg/mL range. The calibration samples were analysed by HPLC-UV method with two replicate injections from each.

Results of the determination of water solubility of the test item

Sampling time	Measured concentrationofTest Item (g/L )		Measured pH
	Test vessels	Mean
After 24h	27.42	27.50	1.73
	27.37		1.81
	27.72		1.74
After 48h	28.75	28.81	1.74
	28.89		1.74
	28.79		1.74
After 72h	28.74	28.71	1.74
	28.76		1.73
	28.64		1.75
Solubility ofthe test item (g/L) with the 95% confidence interval:		28.34 ± 1.81	-
RSD %:		3	-
Ultrapure Water		-	6.8

Conclusions:

The water solubility of the test item was determined to be 28.34 ± 1.81 g/L (95 % confidence interval) at 20 °C ± 0.5 °C using the shake-flask method.

Executive summary:

The water solubility was determined according to OECD 105, Regulation (EC) No. 440/2008 Method A.6 and OPPTS 830.7840 using the shake flask method with HPLC analysis. About 7.5 mg test substance were weighed into 100 mL stoppered Erlenmeyer flasks (three parallels) according to the estimated solubility based on the Preliminary Test. After the addition of 50 mL ultra-pure water, the flasks were agitated at 30 °C. After one and two days, another three samples were prepared and added to shaker, respectively. After the pre-incubation time the nine test vessels were removed and re-equilibrated at 20 °C for 24 hours. Thereafter the content of the flasks was centrifuged and the concentration in the clear aqueous phase was determined by HPLC. The samples were diluted before the analysis (two parallel dilutions). The pH of each sample was recorded. The water solubility of the test substance was determined to be 28.34 ± 1.81 g/L (95 % confidence interval) at 20 °C ± 0.5 °C (pH 1.73 to 1.81).

Description of key information

The water solubility of the test item was determined to be 28.34 ± 1.81 g/L (95 % confidence interval) at 20 °C ± 0.5 °C using the shake-flask method.

Key value for chemical safety assessment

Water solubility:

28.34 g/L

at the temperature of:

20 °C

Additional information

The water solubility was determined according to OECD 105, Regulation (EC) No. 440/2008 Method A.6 and OPPTS 830.7840 using the shake flask method with HPLC analysis (reference 4.8-1). About 7.5 mg test substance were weighed into 100 mL stoppered Erlenmeyer flasks (three parallels) according to the estimated solubility based on the Preliminary Test. After the addition of 50 mL ultra-pure water, the flasks were agitated at 30 °C.After one and two days, another three samples were prepared and added to shaker, respectively.After the pre-incubation time the nine test vessels were removed and re-equilibrated at 20 °C for 24 hours. Thereafter the content of the flasks was centrifuged and the concentration in the clear aqueous phase was determined by HPLC.The samples were diluted before the analysis (two parallel dilutions). The pH of each sample was recorded. The water solubility of the test substance was determined to be 28.34 ± 1.81 g/L (95 % confidence interval) at 20 °C ± 0.5 °C (pH 1.73 to 1.81).