Tris(2-ethylhexyl) phosphate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 August 2016 to 14 September 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study was conducted in accordance wiith international guidelines and in accordance with GLP. All relevant validity criteria were met, with the caveat of the guideline deviation noted in Materials and Methods.

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

27 July 1995

Deviations:

yes

Remarks:

In accordance with Paragraph 23, the difference between the last two measurements was >15 %. As there was no increasing tendency in the 3 measurements, the water solubility was determined as an average of flasks 1-3.

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Key result

Water solubility:

0.14 µg/L

Temp.:

20 °C

pH:

ca. 6

Remarks on result:

other: average of flasks 1-2-3

Water solubility:

0.12 µg/L

Conc. based on:

test mat.

Loading of aqueous phase:

100 mg/L

Incubation duration:

24 h

Temp.:

20 °C

pH:

6.1

Remarks on result:

other: flask 3

Water solubility:

0.17 µg/L

Conc. based on:

test mat.

Loading of aqueous phase:

100 mg/L

Incubation duration:

48 h

Temp.:

20 °C

pH:

6

Remarks on result:

other: flask 2

Water solubility:

0.13 mg/L

Conc. based on:

test mat.

Loading of aqueous phase:

100 mg/L

Incubation duration:

72 h

Temp.:

20 °C

pH:

6

Remarks on result:

other: flask 1

Details on results:

In accordance with Paragraph 23, the difference between the last two measurements was >15 %. As there was no increasing tendency in the 3 measurements, the water solubility was determined as an average of flasks 1-3.

Table 1. Water Solubility Results

Test at 20 °C	Flask 1 (72 h)	Flask 2 (48 h)	Flask 3 (24 h)	Mean Value Flasks 1 to 3
Water Solubility of Test Item	0.13 μg/L	0.17 μg/L	0.12 μg/L	0.14 μg/L
pH	6.0	6.0	6.1	-

Conclusions:

The water solubility of the test item was determined to be 0.14 μg/L at 20°C and pH ca 6.

Executive summary:

The water solubility of the test item was determined in accordance with Council Regulations EC No 440/2008, Guideline Part A – Methods for the Determination of the physical-chemical properties, A.6, “Water solubility” (adopted, May 2008) and to the OECD guideline for testing of chemicals No: 105 “Water solubility“ (adopted 27th July 1995).

The flask method was used with a loading rate of 100 mg/L. Three flasks were incubated at 20°C, with sampling occurring at 24, 48 and 72h. Phase separation was carried out by centrifugation (20 minutes, 10000 rpm, 20 °C). Following phase separation, the pH was determined followed by HPLC/MS analysis to determine the dissolved concentration of test item.

The water solubility of the test item was determined to be 0.14 μg/L at 20°C and pH ca 6.

Description of key information

Water Solubility = 0.14 μg/L at 20°C, pH ca 6; OECD 105; Jungheim (2017)

Key value for chemical safety assessment

Water solubility:

0.14 µg/L

at the temperature of:

20 °C

Additional information

In a single key study, the water solubility of the test item was determined, under GLP, according to EU A.6 and OECD 105 guidelines, using the flask method, with a loading rate of 100 mg/L. Three flasks were incubated, with sampling occurring at 24, 48 and 72h. Phase separation was carried out by centrifugation (20 minutes, 10000 rpm, 20°C). Following phase separation, the pH was determined followed by HPLC/MS analysis to determine the dissolved concentration of test item. The results of the three flasks were averaged.

The water solubility of the test item was determined to be 0.14 μg/L, at 20°C and pH ca 6.