Tetramethylsilane

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

other: Information obtained from secondary source

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Principles of method if other than guideline:

Information on method and guideline not stated.

GLP compliance:

not specified

Type of method:

other: Not stated

Key result

Water solubility:

19.6 mg/L

Temp.:

25 °C

Remarks on result:

other: No pH reported

Conclusions:

A water solubility value of 19.6 mg/L at 25°C was reported for the substance in a secondary literature. The original reference was not available for review and no further information is available. The reliability of this result is not assignable.

Reference 2

Endpoint:

water solubility

Type of information:

other: Information obtained from secondary source

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Principles of method if other than guideline:

Information on method and guideline not available.

GLP compliance:

not specified

Type of method:

other: Not stated

Key result

Water solubility:

19.6 mg/L

Temp.:

25 °C

Remarks on result:

other: No pH reported

Conclusions:

A water solubility value of 19.6mg/L at 25°C was reported for the substance in a secondary literature. The original reference was not available for review and no further information is available. The reliability of this result is not assignable.

Reference 3

Endpoint:

water solubility

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

See attached QMRF/QPRF

Principles of method if other than guideline:

The result was obtained using an appropriate QSAR method (see attached QMRF and QPRF for details).

The model is the publically available WaterNT v1.01 program (US EPA 2012). WaterNT is part of EPI Suite v4.11 and may be downloaded from http://www.epa.gov/oppt/exposure/pubs/episuite.htm. The model is based on fragment values. That is, the chemical structure is broken down into its constituent functional groups, and the contribution of each group toward the overall solubility is calculated.

US EPA 2012. WaterNT v. 1.01, US EPA. 2012. Estimation Programs Interface Suite™ for Microsoft® Windows, v 4.10. United States Environmental Protection Agency, Washington, DC, USA. Available at http://www.epa.gov/oppt/exposure/pubs/episuite.htm.

GLP compliance:

no

Key result

Water solubility:

33 mg/L

Temp.:

20 °C

pH:

7

Conclusions:

A water solubility value of 33 mg/L at 20°C was obtained for the substance using an accepted calculation method. The result is considered to be reliable.

Description of key information

Water solubility: 19.6 -33 mg/L at 20-25°C

Key value for chemical safety assessment

Water solubility:

19.6 mg/L

at the temperature of:

25 °C

Additional information

An attempt to measure the water solubility of the substance using the shake flask method in accordance with OECD 105 was considered unsuccessful due to the chemical properties of the substance especially its high volatility. The water solubility of the substance was measured using a modified shake flask method; the modification involved the use of slow-stir method in order to avoid formation of suspension as well as exclusion of pre-incubation at 30°C. Feasibility analyses of the substance in water and standard calibration curves were conducted using gas chromatography. However, the result of water extraction efficiency showed that acceptable extraction efficiencies could not be obtained. The use of several solvents and techniques in order to optimize recovery of the substance from water samples yielded no greater than 22% recovery. Therefore, the water solubility of the substance was assessed using available data from secondary sources and validated QSAR prediction method.

A water solubility value of 33 mg/L at 20°C was determined for the substance using a validated QSAR estimation method. In addition, in available secondary sources to which reliability could not be assigned, a water solubility value of 19.6 mg/L at 25°C was reported for the submission substance. The available results are used as weight of evidence. The lowest water solubility (19.6 mg/L at 25°C) was used for assessment purposes, using the lowest available water solubility for the substance.

However, the maximum achievable concentration under the conditions of two aquatic ecotoxicity studies was determined. In an algal study (Springbourne Smithers 2010), the maximum achievable exposure concentration under testing conditions (standard closed system, minimal headspace, 23°C) was 0.078 mg/l at test start and 0.0079 mg/l geometric mean over 72 hours. In an acute fish study (Springbourne Smithers 2010), the maximum achievable exposure concentration under testing conditions (specially designed closed system to minimise volatilisation, zero headspace, 14°C) was reported as 3.6 mg/L. This suggests that the predicted and reported water solubilities may not be achieved due to the volatile nature of the test substance.